The 100 most-cited articles in Heliyon, 2020

Environmental pollution of heavy metals is increasingly becoming a problem and has become of great concern due to the adverse effects it is causing around the world. These inorganic pollutants are being discarded in our waters, soils and into the atmosphere due to the rapidly growing agriculture and metal industries, improper waste disposal, fertilizers and pesticides. This review shows how pollutants enter the environment together with their fate. Some metals affect biological functions and growth, while other metals accumulate in one or more different organs causing many serious diseases such as cancer. The pharmacokinetics and toxicological processes in humans for each metal is described. In summary, the review shows the physiological and biochemical effects of each heavy metal bioaccumulation in humans and the level of gravity and disquieting factor of the disease.

Plastic pollution is recognized as a severe anthropogenic issue in the coastal and marine ecosystems across the world. Unprecedented and continuous accumulation of growing plastic contaminants into any respective aquatic ecosystem by the anthropogenic sources causes direct and/or indirect interruption to ecosystem structure, functions, and consequently, services and values. Land-based and sea-based sources are the primary sources of these contaminants in various modes that enter the ocean. In this review paper, we focused on highlighting different aspects related to plastic pollution in coastal and marine environments. Plastic pollutants are distributed in the ecosystems in different forms, with different size variations as megaplastic, macroplastic, mesoplastic, and microplastic. Microplastics in primary and secondary forms reveal a widespread distribution in the water, sediment, and biota of the marine and coastal habitats. The microplastic level of different coastal and marine ecosystems nearly ranged from 0.001-140 particles/m 3 in water and 0.2-8766 particles/m 3 in sediments…

In this work, we have presented a very detailed review of the different classification of azo dyes as a function of the number of azo groups and the appropriate functional groups. Then we pointed out some chemical properties of these dyes such as reactivity, isomerization and tautomerism and listed. In the following, we have summarized some recent syntheses of azo dyes and the mechanism of azo dye / polymer conjugation. Finally, we indicate the principle of Gewald's reaction and its application to the synthesis of new azo dyes.

The worldwide spread of COVID-19 has upset the normality of Italian daily life, forcing population to social distancing and self-isolation. Since the containment precautions also concern sport-related activities, home workout remained the only possibility to play sports and stay active during the pandemic. The present study aimed to examine changes in the physical activity levels during self-quarantine in Italy, and the impact of exercise on psychological health. A total of 2974 Italian subjects has completed an online survey, but only 2524 subjects resulted eligible for this study. The questionnaire measured the total weekly physical activity energy expenditure before and during quarantine (i.e. the sum of walking, moderate-intensity physical activities, and vigorous-intensity physical activities) in Metabolic Equivalent Task minutes per week (MET-min/wk) using an adapted version of International Physical Activity Questionnaire and their psychological well-being using the Psychological General Well Being Index. Of the 2524 Italian subjects included in the study, 1426 were females…

Access to quality education is still a major bottleneck in developing countries. Efforts at opening the access to a large majority of citizens in developing nations have explored different strategies including the use of multimedia technology. This paper provides a systematic review of different multimedia tools in the teaching and learning processes with a view to examining how multimedia technologies have proven to be a veritable strategy for bridging the gap in the provision of unrestricted access to quality education and improved learners' performance. The review process includes conducting an extensive search of relevant scientific literature, selection of relevant studies using a pre-determined inclusion criteria, literature analysis, and synthesis of the findings of the various studies that have investigated how multimedia have been used for learning and teaching processes. The review examines various case study reports of multimedia tools, their success and limiting factors, application areas, evaluation methodologies, technology components, and age groups targeted by the…

This article aims to explore the key factors on e-commerce adoption from elements of social psychology, such as attitude, subjective norms, perceived behavioral control, ease of use and perceived usefulness, introducing the study of non-traditional elements like buying impulse, compatibility, and self-efficacy in online stores, contrasting relationships in a cross-cultural environment. The proposed model is tested from quantitative research with a sample of 584 online consumers in Colombia and Spain. The following statistical analyses were conducted: CFA, structural equations, measurement instrument invariance, and multi-group analysis with EQS 6.3 software. The study reveals that self-efficacy in online stores is a key factor in adopting electronic commerce above the cultures studied. Also, there is significant evidence that proves the moderating effect of national culture on several relationships of the model proposed. Results highlight the importance of national culture to understand impulsive buying behavior. The article presents several considerations toward the main elements…

Ligninolytic enzymes play a key role in degradation and detoxification of lignocellulosic waste in environment. The major ligninolytic enzymes are laccase, lignin peroxidase, manganese peroxidase, and versatile peroxidase. The activities of these enzymes are enhanced by various mediators as well as some other enzymes (feruloyl esterase, aryl-alcohol oxidase, quinone reductases, lipases, catechol 2, 3-dioxygenase) to facilitate the process for degradation and detoxification of lignocellulosic waste in environment. The structurally laccase is isoenzymes with monomeric or dimeric and glycosylation levels (10–45%). This contains four copper ions of three different types. The enzyme catalyzes the overall reaction: 4 benzenediol + O 2 to 4 benzosemiquinone + 2H 2 O. While, lignin peroxidase is a glycoprotein molecular mass of 38–46 kDa containing one mole of iron protoporphyrin IX per one mol of protein, catalyzes the H 2 O 2 dependent oxidative depolymerization of lignin. The manganese peroxidase is a glycosylated heme protein with molecular mass of 40–50kDa. It depolymerizes the lignin…

Lactic acid is an organic compound produced via fermentation by different microorganisms that are able to use different carbohydrate sources. Lactic acid bacteria are the main bacteria used to produce lactic acid and among these, Lactobacillus spp. have been showing interesting fermentation capacities. The use of Bacillus spp. revealed good possibilities to reduce the fermentative costs. Interestingly, lactic acid high productivity was achieved by Corynebacterium glutamicum and E. coli, mainly after engineering genetic modification. Fungi, like Rhizopus spp. can metabolize different renewable carbon resources, with advantageously amylolytic properties to produce lactic acid. Additionally, yeasts can tolerate environmental restrictions (for example acidic conditions), being the wild-type low lactic acid producers that have been improved by genetic manipulation. Microalgae and cyanobacteria, as photosynthetic microorganisms can be an alternative lactic acid producer without carbohydrate feed costs. For lactic acid production, it is necessary to have substrates in the fermentation…

The global outbreak of coronavirus disease 2019 (COVID-19) is affecting every part of human lives, including the physical world. The measures taken to control the spread of the virus and the slowdown of economic activities have significant effects on the environment. Therefore, this study intends to explore the positive and negative environmental impacts of the COVID-19 pandemic, by reviewing the available scientific literatures. This study indicates that, the pandemic situation significantly improves air quality in different cities across the world, reduces GHGs emission, lessens water pollution and noise, and reduces the pressure on the tourist destinations, which may assist with the restoration of the ecological system. In addition, there are also some negative consequences of COVID-19, such as increase of medical waste, haphazard use and disposal of disinfectants, mask, and gloves; and burden of untreated wastes continuously endangering the environment. It seems that, economic activities will return soon after the pandemic, and the situation might change. Hence, this study also…

Hydrogels are polymeric networks having the ability to absorb a large volume of water. Flexibility, versatility, stimuli-responsive, soft structure are the advantages of hydrogels. It is classified based on its source, preparation, ionic charge, response, crosslinking and physical properties. Hydrogels are used in various fields like agriculture, food industry, biosensor, biomedical, etc. Even though hydrogels are used in various industries, more researches are going in the field of biomedical applications because of its resembles to living tissue, biocompatibility, and biodegradability. Here, we are mainly focused on the commercially available hydrogels used for biomedical applications like wound dressings, contact lenses, cosmetic applications, tissue engineering, and drug delivery.

Synthesis of iron oxide nanoparticles by the recently developed green approach is extremely promising because of its non-toxicity and environmentally friendly behavior. In this study, nano scaled iron oxide particles (α-Fe 2 O 3 ) were synthesized from hexahydrate ferric chloride (FeCl 3 .6H 2 O) with the addition of papaya ( Carica papaya ) leaf extract under atmospheric conditions. The synthesis of iron oxide nanoparticles was confirmed by systematic characterization using FTIR, XRD, FESEM, EDX and TGA studies. The removal efficiency of remazol yellow RR dye with the synthesized iron oxide nanoparticles as a photocatalyst was determined along with emphasizing on the parameters of catalyst dosage, initial dye concentration and pH. Increasing the dose of iron oxide nanoparticles enhanced the decolorization of the dyes and a maximum 76.6% dye degradation was occurred at pH 2 after 6 h at a catalyst dose of 0.8 g/L. Unit removal capacity of the photocatalyst was found to be 340 mg/g at dye concentration of 70 ppm and at a catalyst dose of 0.4 g/L. The synthesized nanoparticles showed…

The main purpose of this study is to investigate the relationship between students' entrepreneurship education and entrepreneurial mindset as well as understanding the mediating role of attitude and self-efficacy. The approach adopted in this study is a convenience random sampling method, which is widely used in entrepreneurship research. Participants were recruited from several universities in Malang of East Java in Indonesia undergoing an online survey and were calculated using structural equation modeling (SEM). The findings of this current study indicate that entrepreneurship education successfully influences entrepreneurial self-efficacy, entrepreneurial attitude, and the entrepreneurial mindset. On the other hand, entrepreneurial self-efficacy promotes entrepreneurial attitude instead of the entrepreneurial mindset. Furthermore, entrepreneurial attitude plays an essential role in mediating both entrepreneurship education and self-efficacy toward students' entrepreneurial mindset.

Wireless communication developments are creating new sensor capabilities. The current developments in the field of sensor networks are critical for environmental applications. Internet of Things (IoT) allows connections among various devices with the ability to exchange and gather data. IoT also extends its capability to environmental issues in addition to automation industry by using industry 4.0. As water is one of the basic needs of human survival, it is required to incorporate some mechanism to monitor water quality time to time. Around 40% of deaths are caused due to contaminated water in the world. Hence, there is a necessity to ensure supply of purified drinking water for the people both in cities and villages. Water Quality Monitoring (WQM) is a cost-effective and efficient system designed to monitor drinking water quality which makes use of Internet of Things (IoT) technology. In this paper, the proposed system consists of several sensors to measure various parameters such as pH value, the turbidity in the water, level of water in the tank, temperature and humidity of the…

This study was to explore factors predicting the use of e-learning during Corona Virus Disease 2019 (Covid-19) among sport science education students In Indonesia Higher Education Institutions (HEIs). The study was conducted through survey with 974 participating students from five Indonesian HEIs. An extended Technology Acceptance Model (TAM) with facilitating condition as the external factor was implemented to be the theoretical framework of this study. An analysis method through Partial Least Squares Structural Equation Modeling (PLS-SEM) was employed to measure and assess the proposed model. The findings informed that: (1) the TAM-based proposed scale has been successfully explained factors predicting the use of e-learning among Indonesian sport science students during the pandemic; (2) the finding of significant relationships between facilitating condition and perceived ease of use and between facilitating condition and perceived usefulness was reported; and (3) the significant relationships among core components of TAM were found except for one, relationship between perceived…

Nanophotocatalyst MnTiO 3 powders were synthesized by sol-gel technique and characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), as well as their thermal behavior has been studied by differential thermal and thermogravimetric analyses (DTA/TGA). Powders morphology was analyzed by means of Transmission electron microscopy (TEM). Effect of various process parameters like amount of photocatalyst, dye concentration, solution pH and irradiation time on the extent of removal of dye were studied in detail. The photo-degradation was relatively higher using lower amount (0.005 g) of semiconductor, reached rate of 75% and 70% after 240 min for mixed MnTiO 3 /TiO 2 and pure MnTiO 3 nanocatalysts. The kinetic model of photocatalytic degradation of MB follows pseudo-first-order kinetic with a high correlation coefficient values (R 2 > 0.95). These results underline the use of effective, low-cost and easily available MnTiO 3 photocatalyst for the decomposition of pollutants to water under natural sunlight.

Considering the population density, healthcare capacity, limited resources and existing poverty, environmental factors, social structure, cultural norms, and already more than 18,863 people infected, the community transmission of COVID-19 is happening fast. These exacerbated a complex fear among the public. The aim of this article is, therefore, to understand the public perception of socioeconomic crisis and human stress in resource-limited settings of Bangladesh during the COVID-19 outbreak. The sample comprised of 1066 Bangladeshi participants. Principal component analysis (PCA) was considered to design a standardized scale to measure the mental stress and socioeconomic crisis, one-way ANOVA and t-test were conducted to perceive different demographic risk groups; multiple linear regression was applied to estimate the statistically significant association between each component, and classical test theory (CTT) analysis was applied to examine the reliability of each item according to the components to develop a composite score. Without safeguarding the fundamental needs for the…

PURPOSE: Poly (lactic-co-glycolic acid) has received much academic attention for developing nanotherapeutics and FDA has approved it for several applications. An important parameter that dictates the bioavailability and hence the biological effect of the drug is drug release from its delivering system. This study offers a comparative mathematical analysis of drug release from Poly (lactic-co-glycolic acid)-based nanoparticles to suggest a general model explaining multi-mechanistic release they provide. METHODS: Eight release models, zero order, first order, Higuchi, Hixson-Crowell, the square root of mass, the three-second root of mass, Weibull and Korsmeyer-Peppas, as well as the second degree polynomial equation were applied to 60 data sets. The models analysed regarding several types of errors, regression parameters and average Akaike information criterion. RESULTS AND DISCUSSION: , the lowest overall error and AIC for the Weibull model. Weibull model with the mean AIC = -36.37 and mean OE = 7.24 and the highest NE less than 5, 10, 15 and 20 % in most of the cases best fits the…

Aims The goal of this study was to review the content posted in available local Jordanian Facebook groups to explore the perceptions of parents regarding the challenges of distance learning faced by their children during the coronavirus outbreak in Jordan. Method The Facebook search engine was used to identify local Facebook groups. The search keywords included distance learning, parents, and Jordan. Several faculty professors reviewed the posts and discussion flow on distance learning posted in Facebook groups from March 15 th to April 25 th 2020. Results The study identified a total of 248 posts and threads which categorized thematically for further analysis. The selected threads and answers revealed four underlying themes: (1) personal barriers (2) technical barriers (3) logistical barriers and (4) financial barriers. Conclusion Overall, parents were not limited to their daily routines during the pandemic. They performed the responsibility of helping school in teaching students. Many parents faced many types of barriers in their endeavors to assist their children with distance…

Viral infections are responsible for many illnesses, and recent outbreaks have raised public health concerns. Despite the availability of many antiviral drugs, they are often unsuccessful due to the generation of viral mutants and less effective against their target virus. Identifying novel antiviral drugs is therefore of critical importance and natural products are an excellent source for such discoveries. Coumarin is one such natural compound that is a potential drug candidate owing to its properties of stability, solubility, and low toxicity. There are numerous evidences showing its inhibitory role against infection of various viruses such as HIV, Influenza, Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16). The mechanisms involve either inhibition of proteins essential for viral entry, replication and infection or regulation of cellular pathways such as Akt-Mtor (mammalian target of rapamycin), NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells), and anti-oxidative pathway including NrF-2 (The nuclear factor erythroid 2 (NFE2)-related factor 2). This review…

The need for a good understanding of the relationship between financial inclusion and economic growth has become a significant concern in national development. Both sectors play an essential role in formulating income distribution policies and reducing poverty, evidence from Eastern Indonesia. This paper, therefore, empirically analyzes the contribution of the financial inclusion to economic growth, poverty alleviation and income inequality in Eastern Indonesia. The Toda-Yamamoto VAR bivariate causality model and the dynamic Panel Vector Autoregression (PVAR) were the two approaches used in this research. The effect and relationship of financial inclusion on economic growth, poverty, inequality and other factors were analyzed using PVAR, and Toda-Yamamoto VAR bivariate causality model, respectively. The results of the bivariate causality model indicate a high relationship level between financial inclusion, economic growth, poverty, and income distribution in Eastern Indonesia. The socio-economic growth has a positive impact on the level of financial inclusion, with a negative impact…

Pharmaceutical and personal care products (PPCPs) are the one of sub-class under emerging organic contaminants (EOCs). Ibuprofen is the world's third most consumable drug. This drug enters into our water system through human pharmaceutical use. It attracts the attention of environmentalist on the basis of risk associated, presence and transformation in the environment. The detection and removal are the two key area where we need to focus. The concentration of such compounds in waterbodies detected through conventional and also by the advanced methods. This review we described the available technologies including chemical, physical and biological methods, etc used the for removal of Ibuprofen. The pure culture based method, mixed culture approach and activated sludge culture approach focused and pathway of degradation of ibuprofen was deciphered by using the various methods of structure determination. The various degradation methods used for Ibuprofen are discussed. The advanced methods coupled with physical, chemical, biological, chemical methods like ozonolysis, oxidation and…

Urban growth and land-use change are a few of many puzzling factors affecting our future cities. Creating a precise simulation for future land change is a challenging process that requires temporal and spatial modeling. Many recent studies developed and trained models to predict urban expansion patterns using Artificial Intelligence (AI). This study aims to enhance the simulation capability of Cellular Automata Markov Chain (CA-MC) model in predicting changes in land-use. This study integrates the Artificial Neural Network (ANN) into CA-MC to incorporate several driving forces that highly impact land-use change. The research utilizes different socio-economic, spatial, and environmental variables (slope, distance to road, distance to urban centers, distance to commercial, density, elevation, and land fertility) to generate potential transition maps using ANN Data-driven model. The generated maps are fed to CA-MC as additional inputs. We calibrated the original CA-MC and our models for 2015 cross-comparing simulated maps and actual maps obtained for Irbid city, Jordan in 2015.…

BACKGROUND: The COVID-19 pandemic has aggregated mental health sufferings throughout the entire world. Suicide completions are the extreme consequences of COVID-19 related psychological burdens, which was reported in many countries including Bangladesh. However, there are lack of study assessing COVID-19 related human stress and its' associations with other relevant factors affecting quality of life in the country, and which were explored in the present study. METHODS: An online based survey was carried out among 340 Bangladeshi adult populations (65.90% male; mean age 26.23 ± 6.39) by utilizing the socio-demographics, possible human stress due to COVID-19 pandemic and its consequences. Dataset were analysed through a set of statistical tools e.g., T-test, one-way ANOVA, Pearson's Correlation Matrix (PCM), Principal Component Analysis (PCA), and Cluster Analysis (CA). RESULTS: About 85.60% of the participants are in COVID-19-related stress, which results in sleep shortness, short temper, and chaos in family. Fear of COVID-19 infection (i.e., self and/or family member(s), and/or…

Climate change is a major environmental and socioeconomic challenge in Ethiopia in recent decades. The study site is one of the climate change prone areas affected by climate variability and extreme events. Therefore, a better understanding of area-specific and adaptation is crucial to develop and implement proper adaptation strategies that can alleviate the adverse effects of climate change. Therefore, this work was aimed to identify determinants of farmers' adoption of climate change adaptation strategies in Gondar Zuria District of northwestern Ethiopia. Primary data were collected through semi-structured questionnaires, observation, and interviews . Besides, the secondary data were also obtained from journal articles, reports, governmental offices, and the internet. The Multinomial and Binary logistic regression models with the help of the Statistical Package for Social Sciences (SPSS) (21 th edition) were used to analyze the data. The multinomial logistic regression model was used to estimate the influence of the socioeconomic characteristics of sample households on the…

Composting is a natural process that stems through microbial succession, marking the degradation and stabilization of organic matter present in waste. The use of microbial additives during composting is considered highly efficient, likely to enhance the production of different enzymes resulting in better rate of waste degradation. In lesser developed countries, composting has emerged as a vital technology to recycle the biodegradable waste while generating a useful product. Depending on the composition of the waste material, it can either directly undergo composting or homogenized prior to secondary waste treatment methods such as landfilling. However, a relatively expensive downstream handling all along is a main hurdle towards economics of the process. Although basic methodology and recent approaches are known in crucial aspects of the process through various reviews, exploring the behavior of effective microbial additives will be resourceful. In this review, to fill in the gap, studies related to microbial composting of municipal solid and food waste were acknowledged. Here in,…

Investigating the antecedents of tourist behavioral intentions and its relations with the preceding factors has become an interest of researchers very recently. However, domestic tourism is one of the neglected forms of tourism among academics and policymakers in developing countries in general. This study, therefore, has tried to simultaneously analyze (i) the relationships among motivations (push and pull), satisfaction and behavioral intentions (intention to revisit and willingness to recommend), and (ii) the direct and indirect effects of motivations on the behavioural intentions of domestic tourists in the formation of domestic tourism behavioural model. The relationships were structurally analyzed with Maximum Likelihood Estimation (MLE) method of Structural Equation Modeling (SEM) using data collected from 386 domestic tourists from four destination sites in Ethiopia. The results revealed that both pull and push travel motivations were found to be significant predictors of overall satisfaction. Moreover, the direct effects of pull travel motivation on revisit intention as…

Herein, CuO/ZnO nanocomposites at different ratios were successfully synthesized through a green biosynthesis approach. This was performed by harnessing the fungal-secreted enzymes and proteins during the sol-gel process for nanocomposites seed growth. All fabricated nanoparticles/nanocomposites were characterized using Fourier Transform Infra-Red (FT-IR) Spectroscopy, X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM-EDX) and X-ray Photoelectron Spectroscopy ( XPS) analyses. The photocatalytic degradation efficacy of the synthesized nanocomposites was evaluated using a cationic methylene blue (MB) dye as a model of reaction. Results obtained from the FT-IR and EDX analyses revealed that CuO-NPs, ZnO-NPs, CuO/ZnO 50/50 , CuO/ZnO 80/20, and CuO/ZnO 20/80 were successfully prepared by harnessing the biomass filtrate of Penicillium corylophilum As-1. Furthermore, XRD and TEM revealed the variation in the particle size of the nanocomposites (10–55 nm) with the ratio of the nanoparticles. Notably, the size of the nanocomposites was…

Recently, the demand for functional foods in the global market has increased rapidly due to the increasing occurrences of non-communicable diseases and technological advancement. Antioxidant peptides have been suggested as ingredients used to produce health-promoting foods. These peptides are encrypted from various food derived protein sources by chemical and enzymatic hydrolysis, and microbial fermentation. However, the industrial-scale production of antioxidant peptides is hampered by different problems such as high production cost, and low yield and bioactivity. Accordingly, novel processing technologies, such as high pressure, microwave and pulsed electric field, have been recently emerged to overcome the problems associated with the conventional hydrolysis methods. This particular review, therefore, discussed the current processing technologies used to produce antioxidant peptides. The review also suggested further perspectives that should be addressed in the future.

PURPOSE: Severe acute respiratory coronavirus 2 (SARS-CoV-2) cases are overgrowing globally and now become a pandemic. A meta-analysis was conducted to evaluate the impact of age, sex, comorbidities, and clinical characteristics on the severity of COVID-19 to help diagnose and evaluate the current outbreak in clinical decision-making. METHODS: PubMed, ScienceDirect, and BMC were searched to collect data about demographic, clinical characteristics, and comorbidities of COVID-19 patients. Meta-analysis was conducted with Review Manager 5.3. Publication bias was assessed using Egger's test and Begg-Mazumdar's rank correlation. RESULTS: Fifty-five studies were included in this meta-analysis, including 10014 patients with SARS-CoV-2 infection. Male cases and cases with an age of ≥50 years (OR = 2.41, p < 0.00001; RR = 3.36, p = 0.0002, respectively) were severely affected by SARS-CoV-2. Patients having age≥65 years are not associated (p = 0.110) with the severity of COVID-19. Presence of at least one comorbidity or hypertension, diabetes, cerebrovascular disease, cardiovascular diseases,…

The present study examined relationships among leadership styles, work engagement and work outcomes designated by task performance and innovative work behavior among information and communication technology professionals in two countries: Ethiopia and South Korea. In total, 147 participants from Ethiopia and 291 from South Korea were made to fill in the self-reporting questionnaire intended to assess leadership styles, work engagement, task performance, and innovative work behavior. To test the proposed hypotheses, multiple linear regression analysis was utilized. The results showed that transformational leadership style had a significant positive relationship with employees' work engagement and innovative work behavior, while transactional leadership style had a significant positive relationship with employees' task performance. However, laissez-faire leadership style had a significant negative relationship with task performance. Work engagement had significant positive relationships with the indicators of work outcomes. Besides, work engagement partially mediated the relationship…

Cellulose nanocrystals (CNCs) were isolated from ramie fibers through chemical pretreatments accompanied by sulfuric acid hydrolysis. The influences of both temperature and hydrolysis time on the properties of CNCs were discussed in the present study. The characterization of CNCs was conducted using FT-IR, XRD, TEM, and TGA. The results showed the characteristics of obtained CNCs were influenced significantly by both temperature and time of hydrolysis. The crystallinity, dimensions, and thermal stability of CNCs were found to reduce by increasing both temperature and reaction time of hydrolysis. The optimal hydrolysis parameters were achieved at 45 °C for 30 min with 58% sulfuric acid to produce CNCs, rod-like particles with a high crystallinity (90.77%), diameter (6.67 nm), length (145.61 nm), and best thermal stability among all CNCs. The obtained CNCs had a higher potential for application of alternative reinforcing fillers in the nanocomposites.

In the last few years, copper and copper oxide nanoparticles were involved in many applications; this encouraged many researchers worldwide to develop more facile synthesis methods. Unprecedentedly, the current study reports a green method for synthesizing copper/copper oxide nanoparticles (Cu/Cu 2 O NPs) using the extract of seedless dates. Cu/Cu 2 O NPs were synthesized according to the chemical reduction method using seedless dates' extract as a reducing agent due to its high content of phenolics and flavonoids. Transmission Electron Microscopy (TEM) revealed that roughly spherical particles were synthesized. Dynamic Light Scattering (DLS) showed that the synthesized Cu/Cu 2 O NPs have an average particle size of 78 nm and zeta potential of +41 mV, indicating a good stability of the particles. Successful synthesis of Cu/Cu 2 O NPs was affirmed through both X-Ray Diffraction (XRD), which revealed the presence of the characteristic peaks of copper at 2θ = 43.2745, 50.4083 and 74.1706°, and UV-Vis. Spectroscopy, which revealed the surface plasmonic resonance peak characterizes Cu/Cu…

This paper aims to explore how entrepreneurship education determines students' entrepreneurial intentions as well as examine the emerging role of the entrepreneurial mindset in supporting this relationship. A quantitative method was applied to gain a better understanding of the relationship between variables utilizing Structural Equation Modeling (SEM) based variance Partial Least Square (PLS). The participants of this study were recruited from several vocational students in East Java of Indonesia by using an online survey. The findings indicate that entrepreneurship education positively influences both students' entrepreneurial intentions and an entrepreneurial mindset. It also reveals a robust correlation between entrepreneurship mindset and students' entrepreneurship intentions. Lastly, this study's finding shows that the entrepreneurship mindset has successfully mediated the relationship between entrepreneurial education and students' entrepreneurial intention.

BACKGROUND: Job satisfaction is an important condition for staff retention in most healthcare Organizations. As a concept, job satisfaction is linked to motivation theory. Herzberg's two factor theory of motivation is used in this study to explore what motivational elements are associated with job satisfaction among medical laboratory professionals (MLPs) in Oman. METHODS: A mixed-method approach was adopted, and focus group discussions (FGDs) were used for data collection. The FGDs were conducted in the main hospitals in Oman. Data were analyzed by directed content analysis, and frequencies of statements related to factors were calculated for a comparison with the Herzberg theory. RESULTS: The following job dissatisfaction factors (hygiene) were identified: health and safety, heavy workload, salary, promotion, recognition and organizational policies. The satisfaction (motivators) were: relationships with co-workers, relationship with leaders, and professional development. CONCLUSIONS: The job dissatisfaction reported was resulted from the absence of hygiene factors and some of the…

This study investigates the impact of CO 2 emissions, population density, and trade openness on the economic growth of five South Asian countries. Using data from 1990 to 2017 the panel co-integration approach of extended neoclassical growth model is used. The obtained results reveal that CO 2 emissions and population density positively and trade openness negatively affect the economic growth in South Asia. The extent of effect of population density is greater than that of CO 2 emissions. Granger causality results exhibit a bidirectional causality between economic growth and CO 2 emissions, and between trade openness and CO 2 emissions. There is a unidirectional causality running from trade openness to economic growth, from population density to CO 2 emissions and from labor to economic growth and population density. A detailed policy prescription is provided based on the findings.

Leaf Extract (LCLE) was investigated using gravimetric, depth of attack and surface analysis techniques. Effect of inhibitor concentrations (0.50-1.00 g/l), temperatures (30-60 °C) and immersion time (4-12 h) was studied on the Inhibition Efficiency (IE) of the extract on Mild Steel (MS) immersed in a 0.5 M HCl solution. The constituents of the proposed inhibitor were identified by using a GC-MS. The media solutions and adsorbed film on MS were characterized using FTIR Spectrophotometer. SEM microgram and surface tester were applied for studying surface morphology and depth of attack profile. The optimum IE of 87.89% was obtained. The LCLE adsorption on MS followed Langmuir isotherm and pseudo-second-order adsorption kinetics. Activation energy (28.71 kJ/mol), entropy (- 0.15 kJ/mol. K), average enthalpy (-28.00 kJ/mol) and Gibbs free energy (-11.43 kJ/mol) obtained at optimum condition indicate exothermic process and physical adsorption mechanism. The result obtained in this study compared well with many reported green inhibitors for MS corrosion.

Diarrhoeal diseases collectively constitute a serious public health challenge globally, especially as the leading cause of death in children (after respiratory diseases). Childhood diarrhoea affecting children under the age of five accounts for approximately 63% of the global burden. Accurate and timely detection of the aetiology of these diseases is very crucial; but conventional methods, apart from being laborious and time-consuming, often fail to identify difficult-to-culture pathogens. The aetiological agent of an average of up to 40% of cases of diarrhoea cannot be identified. This review gives an overview of the recent trends in the epidemiology and treatment of diarrhoea and aims at highlighting the potentials of metagenomics technique as a diagnostic method for enteric infections.

Combating the menace of plastic waste pollution has become a global environmental challenge. Plastic pollution is capable of affecting land, waterways and oceans as a large percentage of marine and land creatures have died due to the fact that plastic is non-biodegradable and it causes hazards to soil. It also emits toxic gasses when exposed or heated up. It blocks drainage lines and fill up land space causing floods and erosion thereby causing deterioration of the Nigerian roads. Plastics wastes are also harmful to human health; they may contain harmful acids which may lead to death. Nigeria, which is the biggest oil exporting country in Africa, relies mainly on the proceeds of the oil trade for its GDP and based strategy in growing her economy. However, with the declination of oil prices and increase in plastic wastes, the world is tending towards energy and sustainable development. Therefore, an urgent need for recycling plastic wastes into a solution for wealth creation is fundamental in Nigeria. This paper therefore seeks to identify favorable methods for recycling plastic…

Pulses and legumes belong to the Fabaceae family which are nutritionally rich especially chickpeas, mungbeans, soybeans, and peas. Pulses and legumes are important source of plant protein in many diets. They are also an excellent reservoir of dietary fiber and complex carbohydrates resulting in low GI (glycemic index). Pulses play vital role in metabolic and physiological processes due to the presence of various bioactive compounds, and the majority of them are phenolic acids, flavonoids, and tannins. Pulses and legumes are also a good source of 15 essential minerals and vitamins, but their bioavailability is low due to the presence of antinutrient factors in it. Biofortification is a method by which the nutritional value of pulses and legumes can be increased with the help of breeding, transgenic techniques, or agronomic practices and thus helps in preventing the malnutrition. In view of these details, pulses and legumes provide immense opportunities for its inclusion in manufacturing snacks and sports foods.

Metacognition is the ability of learners to take necessary steps to plan suitable strategies for solving the problems they face, to evaluate consequences and outcomes and to modify the approach as needed, based on the use of their prior knowledge. Metacognition helps learners to successfully achieve a personal goal by choosing the right cognitive tool for this purpose. The study, therefore, aims to explain the relationship and impact of metacognitive awareness and academic motivation on student's academic achievement. This descriptive and correlational study design has included 200 students (60 males) studying sociology in the College of Mass Communication and Humanities at Ajman University, UAE. Academic intrinsic motivations scale and the metacognitive awareness inventory were used as instruments. PLS-SEM was used to examine the relationship between metacognitive awareness and academic motivation, and their impact on academic achievement. Females obtained significantly higher levels than males on the two scales of metacognitive awareness, as shown in metacognitive knowledge.…

Many of today's online services are designed specifically to encourage impulse buying. Moreover, many studies have shown that with the assistance of Mobile Augmented Reality, retailers have the potential to significantly improve their sales. However, the effects of Mobile AR on consumer impulse buying behavior have yet to be examined, particularly in the tourism field. Consequently, the present study integrates the Technology Acceptance Model (TAM), Stimulus-Organism-Response (SOR) framework, and flow theory to examine the effects of Mobile AR apps on tourist impulse buyingbehavior. The research model is implemented using an online questionnaire, with the results analyzed by Partial-Least-Squares Structural Equation Modeling (PLS-SEM) approach. The results obtained from 479 valid samples show that the characteristics of Mobile AR apps play an important role in governing tourist behavior in making unplanned purchases. In particular, as the utility, ease-of-use, and interactivity of the apps increase, the perceived enjoyment and satisfaction of the user also increase and give rise to…

Aging is a degenerative, biological, time-dependent, universally conserved process thus designed as one of the highest known risk factors for morbidity and mortality. Every individual has its own aging mechanisms as both environmental conditions (75%) and genetics (25%) account for aging. Several theories have been proposed until now but not even a single theory solves this mystery. There are still some queries un-answered to the scientific community regarding mechanisms behind aging. However, oxidative stress theory (OST) is considered one of the famous theories that sees mitochondria as one of the leading organelles which largely contribute to the aging process. Many reactive oxygen species (ROS) are produced endogenously and exogenously that are associated with aging. But the mitochondrial ROS contribute largely to the aging process as mitochondrial dysfunction due to oxidative stress is considered one of the contributors toward aging. Although ROS is known to damage cell machinery, new evidence suggests their role in signal transduction to regulate biological and physiological…

Drought is one of the major abiotic stresses that affects crop yield worldwide. An eco-friendly tool that can broadly improve plants' tolerance to water stress is bioionocula comprising plant growth-promoting rhizobacteria (PGPR). In this study, the effect of two PGPR Cupriavidus necator 1C2 (B1) and Pseudomonas fluorescens S3X (B2), singly and/or co-inoculated at two inocula sizes (S1 - 3 × 10 3 cells g −1 dry weight (dw) soil and S2 - 3 × 10 6 cells g −1 dw soil), on growth, nutrient uptake, and use efficiency was assessed in maize ( Zea mays L.) plants grown at three levels of irrigation (80% of water holding capacity (WHC) – well-watered, 60% of WHC - moderate water deficit stress, and 40% of WHC - severe water deficit stress) in a greenhouse experiment. The impact of water deficit and bioinoculants on soil microbial activity (fluorescein diacetate hydrolysis) was also evaluated. Moderate and severe water deficit negatively affected soil microbial activity, as well as, maize growth, by reducing plants' shoot biomass and increasing root/shoot ratio at 60 and 40% of WHC.…

Biomass torrefaction has gained widespread attention due to its benefits as a standalone process to improve biomass properties to be at par or similar to those for coal in electricity generation or as a pretreatment step before pyrolysis and gasification processes. It has also found application in other processes like steel production where it is aiming to replace coal or work alongside coal by co-firing the coal with biomass at certain proportions. There have been a lot of papers on biomass torrefaction review, but this paper tried to look at a different angle to show other aspects of torrefaction and how it links to other technologies as well as the chemistry behind it. Overall, the process has seen a big shift in the technology it utilizes, and the hope is that it will make the process more viable and applicable in future. The focus starts from the raw biomass, how it is analysed and the different analysis that are performed to determine relevant information about biomass properties. There are different reactors that are used but to date there is not a preferred one as they have…

Graphene oxide (GO) based on coconut shell waste was successfully synthesized using a modified Hummers method, and the obtained GO was confirmed using XRD, FTIR, Raman spectroscopy, UV-Vis spectroscopy, and SEM-EDX. The XRD spectroscopy obtained the fractional content of the 2H graphite phase of 71.53%, 14.47% phosphorus, 10.02% calcium, and 3.97% potassium in coconut shell charcoal, where the GO sample tend to forms a phase of reduced graphene oxide (rGO). FTIR spectra shows compound functional groups of hydroxyl (- OH) at peak 1 (3449.92 cm −1 ), carboxyl (-COOH) at peak 2 (1719.42 cm −1 ) and peak 3 (1702.62 cm −1 ), and alcohol (C–OH) at peak 4 (1628.12 cm −1 ) and epoxy (CO) at peak 5 (1158.51 cm −1 ), which is similar to the GO synthesis from pure graphite. Raman spectroscopy analysis shows that the value of the I D /I G intensity ratio of the GO sample was 0.89 with a 2D single layer, and SEM results showed that surface morphology with an abundance of granular particles were found with different size distribution. The UV-visible results showed sufficient optical properties…

The study investigated perception of workload balance and employee job satisfaction in work organisations. It sought to find out the extent to which employee perception of workload balance influences job satisfaction. Seven hundred and sixty-four (764) randomly selected employees from 8 multinational organizations and two private universities in Nigeria participated in the study. Structural equation modelling was employed. Results show that comparison of workload with those of colleagues and employees' role alliance with their competencies significantly influence their perception of workload balance and job satisfaction, organisation's staff strength influences perception of workload balance and employees' perception of workload balance significantly influences job satisfaction.

In the present study, silver nanoparticles (AgNPs) were synthesized using aqueous leaf extracts of three Congolese plant species, namely Brillantaisia patula (BR-PA), Crossopteryx febrifuga (CR-FE) and Senna siamea (SE-SI). The obtained AgNPs were studied for their optical, structural, surface morphological and antibacterial properties. The prepared AgNPs were characterized by using UV-Visible spectra, Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray spectroscopy (EDX) and X-ray diffractometer (XRD). The synthesized nanoparticles were spherical shaped and well-dispersed with average sizes ranging from 45 to 110 nm. The AgNPs derived from BR-PA, CR-FE and SE-SI exhibited higher antibacterial activity against three bacterial pathogens of the human skin compared to their respective crude extracts and AgNO 3 . This indicated that the biomolecules covering the nanoparticles may enhance the biological activity of metal nanoparticles. Hence, our results support that biogenic synthesis of AgNPs from Congolese plants constitutes a potential area…

Jordan imports 94% of its oil and gas (fossil fuels) to meet its energy needs, leaving it vulnerable to variations in fuel price. Jordan's demand for energy is growing at a rate of 3% annually. In response, the government set a target of obtaining 10% of its energy needs from renewable energy resources by increasing electricity generation share from the present 1.13 GW-1.8 GW by 2020. The sources of generation include abundant solar, wind, and biomass resources, which also enhance economic growth and reduce pollution. This article analyzed the current energy situation in Jordan and assessed the available renewable energy resources potential for direct investments. The actual contribution of clean energy is still moderate at roughly 7% of total energy demand, despite the efforts placed on the development of alternative energy resources. The national electricity supply and demand are presented, and the government initiatives, financial incentives, and tax exemptions to encourage investments in clean energy are also discussed. The renewable energy policy generates future opportunities…

Chemical compositions, biological and antioxidant activities of plants are widely affected by several parameters and conditions, such as geographical and climatic conditions, type of extract (aqueous or organic), as well as the polarity of the extracting solvent. Therefore the present study was the first one designed to study the phytochemical composition, the content of polyphenols, tannins and flavonoids, the antioxidant activities and the chemical composition analysis by FTIR spectroscopic of organic (ethanol, methanol, ethyl Acetate, petroleum ether) and aqueous extracts of Marrubium vulgare L. leaves, collected from two different sampling localities in the North-East of Morocco: Oulad Daoud Zkhanine and the Cape Three Forks. A phytochemical screening was carried out by specific coloring and precipitation reactions. The colorimetric method Folin- Ciocalteu was used for the quantification of total phenolic content. The method of aluminum chloride was employed for the quantification of total flavonoid content and the method of vanillin for the determination of tannins. The…

Nutritional and microbiological psychiatry, especially the contribution of the gut microbiota to depression, has become a promising research field over the past several decades. An imbalance in the "microbiota-gut-brain axis", which reflects the constant bidirectional communication between the central nervous system and the gastrointestinal tract, has been used as a hypothesis to interpret the pathogenesis of depression. Alterations in gut microbiota composition could increase the permeability of the gut barrier, activate systemic inflammation and immune responses, regulate the release and efficacy of monoamine neurotransmitters, alter the activity and function of the hypothalamic-pituitary-adrenal (HPA) axis, and modify the abundance of brain-derived neurotrophic factor (BDNF), eventually leading to depression. In this article, we review changes in gut microbiota in depressive states, the association between these changes and depression-like behavior, the potential mechanism linking gut microbiota disruptions and depression, and preliminary attempts at using gut microbiota…

informal markets selling several homemade gastronomic plant and animal-based products and culinary preparations, as well as wild and cultivated plants, and sometimes family butchered barnyard animals are extremely popular in Ukraine. In this field study that we conducted over a few years we inventoried the most relevant food plant products sold in these markets and we analysed how these markets represent remarkable food refugia for several local niche foods. In addition, we researched the historical and socio-economic reasons for the start, survival, and revival of this phenomenon, which had its origin during the Communist period. We furthermore evaluated similar recent trends in other Eastern European countries and especially those which had a very different post-Communist trajectory with the aim of addressing the possible factors affecting their survival and what could be done to preserve their existence. In particular, in a few of these countries (i.e. Azerbaijan) we observed how informal food markets represent experimental fields where gastronomic knowledge is not only…

The studies of advanced materials in environmental remediation and degradation of pollutants is rapidly advancing because of their wide varieties of applications. BiFeO 3 (BFO), a perovskite nanomaterial with a rhombohedral R3c space group, is currently receiving tremendous attention in photodegradation of dyes. The photocatalytic activity of BFO nanoparticle is a promising field of research in photocatalysis. BFO nanomaterial is a photocatalyst enhanced by doping because of its reduce bandgap energy (2.0–2.77 eV), multiferroic property, strong photoabsorption and crystal structure. The material has proven to be very useful for the degradation of dyes under visible light irradiation among other photocatalysts. Its exceptional nontoxicity, suitability, low cost and long term excellent stability makes it an efficient photocatalyst for the degradation of effluents from textile and pharmaceutical industries which ended-up in the environment and now a major concern of the modern world. This mini-review attempts to provide some detailed synthetic routes of BFO and BFO related…

The copper nanoparticles (CuNPs) have attracted much attention due to their application in diverse fields. The applications of CuNPs depend on their physical and chemical properties. This study presents the first report for the use of medicinal fruit extract of Piper retrofractum Vahl as an eco-friendly reagent in the synthesis of CuNPs using copper sulfate as a starting material. Piper retrofractum Vahl extract was employed as a bioreductor as well as a capping agent in the formation of CuNPs. The reaction process was assisted by sonication and stirring. The influences of extract concentration, pH, temperature, and reaction time on the size of CuNPs were studied in detail. The morphology and structure of synthesized CuNPs were characterized by UV-Vis, FT-IR, SEM-EDS, TEM, and XRD. The UV-Vis measurement showed the surface plasmon resonance (SPR) peak at 234-255 nm, whereas FTIR characteristic peaks of metal-oxygen (Cu–O) were confirmed in the range 550-570 cm −1 and Cu–O–H bonds led to bending absorptions in the region 870-880 cm −1 . The synthesized CuNPs possess the spherical…

Unmanned Aerial Vehicles were first introduced almost 40 years ago and their applications have increased and diversified substantially since then, in both commercial and private use. One of the UAVs main issues when it comes to mobility is that the power sources available are inadequate, this highlights an area for improvement as the interest in drones is on the increase. There exist many different types of power supplies applied to UAVs, however each has their own limitations and strengths that pertain to weight contributions, charging and discharging times, size, payload capabilities, energy density and power density. The aim of this paper is to review the main power sources available for UAVs, determine their shortfalls, compare the power sources with each other and offer suggestions as to how they can be improved - hence identifying where the gap lies for developing better alternative power sources.

Abstract The ongoing pandemic of the coronavirus disease 2019 (COVID - 19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). We have performed an integrated sequence-based analysis of SARS-CoV2 genomes from different geographical locations in order to identify its unique features absent in SARS-CoV and other related coronavirus family genomes, conferring unique infection, facilitation of transmission, virulence and immunogenic features to the virus. The phylogeny of the genomes yields some interesting results. Systematic gene level mutational analysis of the genomes has enabled us to identify several unique features of the SARS-CoV2 genome, which includes a unique mutation in the spike surface glycoprotein (A930V (24351C>T)) in the Indian SARS-CoV2, absent in other strains studied here. We have also predicted the impact of the mutations in the spike glycoprotein function and stability, using computational approach. To gain further insights into host responses to viral infection, we predict that antiviral host-miRNAs may be controlling…

Uncontrolled decomposition of agro-industrial waste leads to extensive contamination of water, land, and air. There is a tremendous amount of waste from various sources which causes serious environmental problems. The concern in the disposal problems has stimulated research interest in the valorization of waste streams. Valorization of the wastes not only reduces the volume of waste but also reduces the contamination to the environment. Waste from food industries has great potential as primary or secondary feedstocks for biopolymer production by extraction or fermentation with pre-treatment or without pre-treatment by solid-state fermentation to obtain fermentable sugars. Various types of waste can be used as substrates for the production of biomaterials but recently more focus has been observed on the agro-industrial wastes which have a high rate of production worldwide. This review collates in detail the different food wastes used for biopolymer, technologies for the production and characterization of the biopolymers, and their economic/technical viability.

Mycotoxins present a great concern to food safety and security due to their adverse health and socio-economic impacts. The necessity to formulate novel strategies that can mitigate the economic and health effects associated with mycotoxin contamination of food and feed commodities without any impact on public health, quality and nutritional value of food and feed, economy and trade industry become imperative. Various strategies have been adopted to mitigate mycotoxin contamination but often fall short of the required efficacy. One of the promising approaches is the use of bioactive plant components/metabolites synergistically with mycotoxin-absorbing components in order to limit exposure to these toxins and associated negative health effects. In particular, is the fabrication of β-cyclodextrin-based nanosponges encapsulated with bioactive compounds of plant origin to inhibit toxigenic fungi and decontaminate mycotoxins in food and feed without leaving any health and environmental hazard to the consumers. The present paper reviews the use of botanicals extracts and their…

The aim of this article is to explore a paradigm shift on Brain Computer Interface (BCI) research, as well as on intervention best practices for training and rehabilitation of students with neurodevelopmental disorders. Recent studies indicate that BCI devices have positive impact on students' attention skills and working memory as well as on other skills, such as visuospatial, social, imaginative and emotional abilities. BCI applications aim to emulate humans' brain and address the appropriate understanding for each student's neurodevelopmental disorders. Studies conducted to provide knowledge about BCI-based intervention applications regarding memory, attention, visuospatial, learning, collaboration, and communication, social, creative and emotional skills are highlighted. Only non-invasive BCI type of applications are being investigated based upon representative, non-exhaustive and state-of-the-art studies within the field. This article examines the progress of BCI research so far, while different BCI paradigms are investigated. BCI-based applications could successfully regulate…

Domestic violence in South Africa is a consequence of the complex interplay of patriarchy, culture, and the negative masculine construct. The patriarchal cultural beliefs and traditions that emphasise on male assertiveness and domination of women influence the constructions of masculinity and reinforce domestic violence. The goal of this article was to highlight a relationship between culture, constructions of masculinity, and domestic violence in South Africa. Through adopting an African feminist lens, this paper unpacks how structures of patriarchy manifest in the traditional African context in which many men in South Africa construct and perform their masculinity and the embodied meaning attached to it. The paper argues that gender hierarchy and normative masculine and feminine roles prevalent in most South African cultures have implications for domestic violence. It argues that the inflexible gender hierarchy, which is enforced through culture and the dominant position of men in the home influence domestic violence. The article concludes that attempts to address domestic…

E-commerce has grown steadily since internet access became more available in the mid-1990s. Informativeness plays a key role in online shopping decisions. Potential customers usually collect useful information and do a comparison before considering the purchase. Electronic word-of-mouth (eWOM) is considered a reliable source of information. Customer reviews and influencer reviews can be considered eWOM. They represent customers' sharing of experience and evaluation of a product or service with other potential shoppers. There is abundant evidence concerning the influence of eWOM on purchase intention. However, there are few studies on influencer reviews and purchase intention. This study aims to investigate the impact of customer review and influencer review to purchase intention and the mediating role of trust to those relationship. A quantitative experimental study (2 × 1) was conducted. Two hundred respondents from three cities in Greater Jakarta were divided into two groups to self-rate their opinion on customer review, influencer review, trust and purchase intention. Data…

The key components of photovoltaic (PV) systems are PV modules representing basic devices, which are able to operate durably in outdoor conditions. PV modules can be manufactured using different materials by different fabrication technologies. The main criteria supporting or limiting a successful placement of particular technologies on the market is the cost of electricity produced by PV systems. The Levelized Cost of Energy (LCOE) method takes into account the investment cost, the operating costs, and the total energy produced during the system service life. The influence of price, efficiency and service life of PV modules on LCOE (together with the availability of materials) sets limits for applicable technologies. Over the past 15 years a categorisation of generations of PV cell and module technology groups has been frequently used. The main features of individual technology groups are discussed from the view of the above criteria. Currently, PV modules are required to have: efficiency higher than 14%, price below 0.4 USD/W p and service life of more than 15 years. At present,…

Fear is a powerful driver of human behavior, even more during times of crisis. Panic buying occurs when fear and panic influence behavior leading people to buy more things than usual. So far, no specific scale on this has been found in the major databases, thus the aim of this exploratory study is to develop a Panic Buying Scale (PBS) during COVID-19 pandemic. 393 Brazilians took part in this study (251 women and 142 men), answering a sociodemographic questionnaire and instruments of these variables: (1)panic buying, (2)impulse buying, (3)temporal focus, (4)optimism, (5)risk perception, (6)need for cognition. Data collection was conducted through an online questionnaire which was shared through social media networks, from April 10th to May 4th, 2020. Factorial exploratory and confirmatory analysis indicated that PBS has a unidimensional solution and showed satisfactory reliability indexes. Results revealed that men buy more by panic than women. PBS also was positively correlated with impulse buying, past and future temporal focus, and risk perception; as well as negatively…

The widespread use of organochlorine pesticides (OCPs), essentially for the control of insects and the cultivation of food crops, has led to the pollution of ecosystems. Despite being banned several years ago in the developed world, extensive use remains ongoing on the African continent. This review summarizes the occurrence, distributions, sources, and trends of OCPs in seven environmental matrices (atmosphere, water, sediments, soils, biota, human fluids and food products) in Africa. Findings in this review revealed that α-HCH, β-HCH dichlorodiphenyltrichloroethane (DDTs), and endosulfans were the most persistent OCP residues in the African environment, particularly DDTs in breast milk samples occurring in levels above the WHO stipulated limits, thus indicating a call for concern. Also, there was paucity of data available on OCP concentrations in ambient air. Future research efforts should prioritize testing these pollutants in the atmosphere, especially in countries where they are used more frequently. While most POP analysis studies used gas chromatography coupled to electron…

This study addresses the impacts of metabolites from different microbial taxa on the fabrication and multifunctional biological properties of spherical silver nanoparticles (Ag-NPs). Three microbial taxa, a bacterial ( Bacillus cereus A1-5), actinomycetes ( Streptomyces noursei H1-1), and fungal ( Rhizopus stolonifer A6-2) strains were used for Ag-NPs biosynthesis, whereas Streptomyces noursei is demonstrated for the first time. These isolates were identified using either 16S rRNA or ITS gene sequencing. Characterization of Ag-NPs was done using color change analysis, Uv-Vis spectroscopy, FT-IR spectroscopy, XRD, TEM, SEM-EDX, DLS, and Zeta potential analysis. All biosynthesized NPs exhibited spherical shape with different sizes ranged from 6‒50 nm, 6–30 nm and 6–40 nm for NPs obtained by A1-5, H1-1 and A6-2, respectively. The crystalline center cubic face of Ag-NPs was confirmed using XRD at 2 θ values 38.08 o , 44.27 o , 64.41 o and 77.36 o . FT-IR analysis revealed varied intense absorption peaks for biomolecules required for NPs synthesize by each microbial strain. The stability…

This manuscript provides a literature review of connectivism. It presents evidence and thinking in which connectivism, a new learning theory which has typically been used for online learning, is applied to leadership, with a provocative discussion on the yet unexplored opportunities to use connectivism to redefine leadership in the twenty-first century. The paper aims to bridge the gap between the contributions of digital learning in education and the field of leadership theory and development. It seeks to apply the critical tenants of connectivism in education and learning to leadership theory and to stimulate a debate on new forms of leadership.

Microplastics (MP) pollution has become a matter of global concern because of its several deleterious effects on environmental health, especially on the terrestrial environment. The evidence of MP contamination in terrestrial environment is less explored compared to aquatic bodies. However, in Bangladesh despite having high possibility of MP contamination, there is lacking of available research-based evidence. Urban areas soil is subjected to act as a major environmental reservoir for MPs. Thus, this study was carried out to investigate the presence of MP contamination in constructed landfill sites near Dhaka city, Bangladesh. Ten unmixed soil samples were collected from the Aminbazar Sanitary landfill sites, from that thirty replicated samples were investigated via Fourier Transform Infrared Spectroscopy (FT-IR) analysis and Stereomicroscope. The range of physicochemical parameters were found in the soil samples as follows: moisture content; 15.84%–56.54%; soil pH; 5.76–6.02, electric conductivity; 0.1 μs/cm - 2.43 μs/cm, alkalinity; 6.7 ± 1.528–14.33 ± 0.577, TOC; 0.18% ±…

Significant efforts are being performed to make cities smarter and more sustainable. Therefore, there is a need to compare these efforts using evaluation frameworks. According to the literature review, the basic dimensions of smart cities are generally evaluated with the criteria of regional competitiveness, transportation, information and communication technology, economy, natural resources, human and social capital, quality of life and participation of citizens in the management of cities. In this paper, Analytical Network Process (ANP) is used to weight smart and sustainable city criteria. According to the results, while 'smart living' is the most important characteristic with a 35,459% priority, 'smart governance' is the last with 5,738%. The study covers 44 cities around the world and comparisons were made by TOPSIS (Technique for Order Preference by Similarity to Ideal Solution). According to the results, Tokyo, London and New York are in the top three in the overall ranking. But none of these cities is among the top five in terms of smart governance, mobility and…

The purpose of this study is to examine the effect of accrual earnings management and business strategy to bankruptcy risk. Multiple Least Square (MLS) regression and robust regression of M-Estimator regression are performed on financial data of 1,068 non-financial firms listed on the Indonesia Stock Exchange (IDX). The result indicates that there is no relationship between earnings management and bankruptcy risk, while firms that implement either one of two generic business strategies of cost leadership or differentiation, significantly mitigate the risk of bankruptcy. The effect of earnings management to bankruptcy risk is essential for external stakeholders, such as investors and creditors, to assess bankruptcy risk, financial capability, and credit worthiness of a firm, while business strategy effect on bankruptcy risk benefits internal stakeholders, such as managers, in formulating strategies to deal with going concern issues.

century. Over the years, the regrowth of broken bones and diseased hard tissue has remained a major concern in medical research. Since the discovery of hydroxyapatite (HA), a bioceramic compound that possesses the ability to activate bone regrowth and bond directly with regenerated bone, it has subsequently become an indispensable biomaterial. Currently, it is being used across the medical fields due to its exceptional biocompatibility. This became plausible because the main mineral phase of mammalian bones is HA. It has found application in various medical fields like medical instruments, drug delivery, bone and tooth fillers, prosthetics, orthotics, and in-vitro implants. As the importance of HA geometrically increases, it is necessary to critically evaluate and propose the most economic process of synthesizing and manufacturing this important bioceramic material. This review, therefore, highlights the different sources of HA and the synthesis/production methods for each source with a strong emphasis on the environment. Thus, the appraisal was carried out based on the properties…

The aim of this study is to present a new hybrid solar-biomass dryer and carry out thermal analysis based on energy and exergo-sustainability analysis considering all the available exergy stream of solar radiation, air stream through the collector, and exergy of the moisture in the product. The research also presented the environmental impact and economic analysis of using the dryer. Performance evaluations show that at collector efficiency of 20.81%–21.89 %, the developed solar dryers can save between 10 – 21hrs of drying time in drying 5 mm thick plantain slices to 15 % moisture content from initial moisture content of 66 % w.b when compared to drying under the open sun. The improvement potential ranged from 0.036 to 20.6W while the waste exergy ratios and sustainability index ranged from 0.38 - 0.55 and 2.3–6.11 respectively. Application of the solar dryers can save between 44 -3074 of CO 2 entering the atmosphere per year while 2.94 to 205.43$ could also be saved at 10–100% rate of usage when compared to diesel fired dryer. The total energy consumption for drying ranges between…

An analysis is made to illustrate the MagnetoHydroDynamics (MHD) flow and gradient heat transport of a Newtonian fluid over a stretching sheet embedded in a porous matrix. The governing nonlinear partial differential equations are reconstituted as ordinary differential equations utilizing suitable similarity transformation and then treated numerically using 4 th order Runge-Kutta method along with shooting technique and analytically by Homotopy Perturbation Method. The verification of present study with earlier works serves as the benchmark of reliability of the present study. The important outcomes of this study are: porous parameter ( K p ) acts as aiding force i.e when K p is increased from 0.1 to 10 gradually there is a significant growth in velocity and after that rate of increment gets slowdown, greater Eckert number and joule heating parameter cause a rise in temperature as well as enhance the thermal boundary thickness. Consequently rate of heat transfer diminishes as thickness leads to low heat transfer coefficient. The applications of this study are shown in: multiple…

from Iran. Formation of Ag NPs was confirmed through different characterization techniques such as UV-Vis Spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Transmission Electron Microscopy (TEM). UV-Visible spectrophotometer showed absorbance peak at 440 nm due to the Surface Plasmon Resonance (SPR). Based on XRD results and SEM and TEM analysis, AgNPs were crystalline with face-centered cubic geometry and in different sizes ranged 12-30 nm. Furthermore, FTIR Spectroscopy was utilized to recognize the specific functional groups responsible for reducing ion silver to silver nanoparticles and the capping agents available in the leaf extract. In addition, the antibacterial effect of Eco-friendly synthesized nanoparticles and also leaf extract, were evaluated on four pathogens by implementing minimum inhibitory concentration test (MIC) and agar diffusion assay. The MIC results exhibits more inhibiting activity against gram-negative microorganisms (Escherichia coli and Pseudomonas aeruginosa) rather than gram-positive microorganisms (Staphylococcus aureus and…

The microstructures of the activated carbon black microparticles (ACBMPs) generated through both treatments of 20 min ultrasonic and 400 °C thermal energy equivalent have been analyzed properly using scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier-transformed infrared (FTIR) spectroscopy methods. The research was aiming to generate binding or active sites points on the outer surface of the ACBMPs body of which commonly plays an important role in both adsorption and catalytic processes. It was observed that around 150 nm up to 400 nm in average diameter super macro voids with many various turns of nano-scale wells, and around 1.84 angstrom (Å) up to 15.98 Å intraparticle pores were generated. In addition, the parallel planes spacing of the carbonaceous framework sheets, namely d hkl in Miller indexes terminology, of about 4.44 Å up to 2.98 Å constructed the inner particles of the ACBMPs body. A new nomenclature method for the binding or active site shapes identification and classifying them into four categories based on the quadrants terminology, i.e .…

The quality of water supply is assessed by its physico-chemical and bacteriological properties. This study was carried-out with the aim of determining the contamination level of domestic water sources of Samaru community, Zaria, Northcentral Nigeria in order to observed the trend of change in quality of these water sources, if any. This was with a view to safeguard the public health of the riparian users against a possible outbreak of water borne diseases. Water samples were collected and analyzed for bacteriological and physicochemical quality using standard procedures. The results showed that the mean values recorded for physico-chemical parameters among the domestic water sources were within stipulated limits of WHO for safe drinking water except for chloride mean value of 314 ± 142.4 mg/L recorded in borehole water. The total heterotrophic bacterial counts recorded in tap, borehole, well, reservoir and river water samples (3.67 × 10 6 ± 1.25 × 10 6 , 5.67 × 10 6 ± 8.49 × 10 5 , 2.60 × 10 7 ± 6.09 × 10 6 , 5.07 × 10 6 ± 1.59 × 10 6 and 6.02 × 10 7 ± 3.69 × 10 6 ) exceeded the WHO…

Customer is considered as the king in the world of business. The issue of customer satisfaction in electronics home appliances has received greater attention from academics and practitioners. In other words, customer satisfaction is a vital consideration in marketing. With the development of technology, new and innovative electronic home appliances are available in the market. Customers purchase and use the costly electronic home appliances where the satisfaction issue is an important concern. In Bangladesh, working families find the electronic home appliance very necessary. Companies offer state-of- the-art appliances for customers' household works. Therefore, the study intends to investigate the effect of product quality (PQ), quality of service (SQ) and perceived value on customer satisfaction (CS). In addition, this study also seeks this relationship shaped by customer's perceived value (CPV) as a key mechanism and interacted by social media usage. A total of 300 households were selected on a judgmental basis from Dhaka city in Bangladesh using a structured questionnaire.…

Fungal skin infections are the most common global issue for skin health. Fungal infections are often treated by topical or systemic anti-fungal therapy. Topical fungal therapy is usually preferred because of their targeted therapy and fewer side effects. Advanced topical carriers because of their distinct structural and functional features, overcome biopharmaceutical challenges associated with conventional drug delivery systems like poor retention and low bioavailability. Literature evidence indicated topical nanocarriers loaded with anti-fungal agents display superior therapeutic response with minimum toxicity. Nanocarriers often used for topical anti-fungal medication includes Solid-Lipid nanoparticles, Microemulsions, Liposomes, Niosomes, Microsponge, Nanogel, Nanoemulsion, Micelles etc. This review summarizes recent advances in novel strategies employed in topical carriers to improve the therapeutic performance of anti-fungal drugs.

From last two to three decades, the world is facing the threat of finding treatment for Cancer. This disease is striking almost ten million people every year throughout the world. Anticancer drugs are those which are used to cure malignant disease i.e. Cancer. These anticancer drugs are available in different forms including alkalyting agents, hormones and anti metabolites. Various examinations reveals that, there will be a adjacent relationship between the characteristics of alkanes and the anticancer drugs viz. Boiling point, melting point, enthalpy etc. with their chemical structures. In this proposed work, various topological indices are defined on some anticancer drugs to help the researchers to know the physical characteristics and chemical reaction associated with them. We also discuss the QSPR analysis of thirteen degree based topological indices. Further, we showcase that the characteristics have good correlation with physico-chemical characteristics of anticancer drugs.

The terahertz (THz) region lies between the microwave and infrared regions of the electromagnetic (EM) spectrum such that it is strongly attenuated by water and very sensitive to water content. Here, we numerically present what is to our knowledge the detecting system based on THz reflectance spectral responses data in the diagnosis of in vivo and ex vivo of some cancer's samples such as skin, breast and colon cancer tissue samples. The numerical analysis on the use of semiconductor metamaterial design/device as a complex refractive index (CRI) biosensor have been carried out. We demonstrate the application of terahertz pulse detecting (TPD) in reflection geometry for the study of normal and cancerous biological tissues. THz radiation has very low photon energy and thus it does not pose any ionization hazard for biological tissues. The sensitivity of THz radiation to polar molecules, such as water, makes TPD suitable to study the diseases in human body. By studying the THz pulse shape in the time domain, we have been able to differentiate between diseased and normal tissue for the…

Chitosan and chitin are mainly extracted from shells of fish such as lobsters, crabs or shrimps. Originally, the raw material and the two compounds are identical. This study aims to show the acid concentration effect on chitosan extraction from shrimp shells between concentrated and diluted acid; on surface morphology, thermal resistance, structural, elemental composition, optical and opto-electronic properties. It also aims to reduce the production time and increase the quantity. We focused mainly on comparing between Physico-chemical properties of chitosans extracted by diluted (1M) and concentrated (20%) Chloric acids, and sometimes we compare by other concentrated acids like nitric acid (70%) and sulphuric acid (98%). We performed the product's characterization by various tools such as: X-ray diffraction (XRD) spectroscopy, X-ray fluorescence (XRF) analysis, UV-Visible spectroscopy, Fourier Transformed Infra-Red (FTIR), Raman Spectroscopy, Thermogravimetry and Derivative Thermogravimetry (TG/DTG), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX)…

COVID-19 has attracted global attention due to its rapid spread around the world with substantial morbidity and associated mortality. Severe COVID-19 can be complicated by the acute respiratory distress syndrome, sepsis and septic shock leading to death. These complications are thought to result from an overactivation of the immune system, leading to a cytokine storm syndrome associated with multiple organ failure. Here, we report that high mobility group box 1 (HMGB1), a prototypical damage-associated molecular pattern (DAMP) and a central mediator of lethal inflammation, could be a potential target for innovative therapeutic strategies for COVID-19. Serum HMGB1 in severe COVID-19 patients is elevated (189.40 ± 140.88 ng/ml). Exogenous HMGB1 induces the expression of SARS-CoV-2 entry receptor ACE2 in alveolar epithelial cells in an AGER-dependent manner. Importantly, genetic (using AGER siRNA) or pharmacological (using glycyrrhizin, chloroquine, hydroxychloroquine, and FPS-ZM1) inhibition of the HMGB1-AGER pathway blocks ACE2 expression. Thus, HMGB1 inhibitors are likewise…

The hydrogen economy is the key solution to secure a long-term energy future. Hydrogen production, storage, transportation, and its usage completes the unit of an economic system. These areas have been the topics of discussion for the past few decades. However, its storage methods have conflicted for on-board hydrogen applications. In this review, the promising systems based on solid-state hydrogen storage are discussed. It works generally on the principles of chemisorption and physisorption. The usage of hydrogen packing material in the system enhances volumetric and gravimetric densities of the system and helps in improving ambient conditions and system kinetics. Numerous aspects like pore size, surface area ligand functionalization and pore volume of the materials are intensively discussed. This review also examines the newly developed research based on MOF (Metal-Organic Frameworks). These hybrid clusters are employed for nano-confinement of hydrogen at elevated temperatures. A combination of the various methodologies may give another course to a wide scope in the area of energy…

BACKGROUND: This study investigated the effect of traditional and improved solar drying methods on the sensory quality and nutritional composition of the dried fruit products; using mangoes and pineapples, as a case study. The fruits were dried under five solar drying methods namely; open sun drying (OSD), black-cloth shade (BCS), white-cloth shade (WCS), a conventional solar dryer (CSD), and a newly improved solar dryer (ISD) technology. The ISD unit was made of a modified solar concentrator plate containing multiple metallic solar collectors arranged in series. The ISD drying cabinet was also enclosed with a specialized greenhouse cover materials. The drying operations were conducted following a completely randomized design (CRD) experimental procedure. RESULTS: The mean drying air temperatures for the OSD, BCS, WCS, CSD and ISD methods were 26.8, 26.7, 24.5, 32.6 and 40.3 °C; respectively. Results showed that the five solar drying methods were capable of retaining the sensory quality and nutritional composition of dried mango and pineapples. The nutritional parameters retained…

In this era of intensive electricity utilization for economic development, the role of urbanization remains inconclusive, especially in developing economies. Here, this study examined the electricity consumption and economic growth nexus in a trivariate framework by incorporating urbanization as an additional variable. Using the recent novel Maki cointegration test, Ng-Perron, Zivot-Andrews, and Kwiatkowski unit root tests along with FMOLS, DOLS and the CCR estimation methods, we relied on an annual frequency data from 1971-2014. Results from FMOLS, DOLS and the CCR regression confirms the electricity consumption-driven economic growth. This is desirable as Nigeria is heavily dependent on energy (electricity) consumption. A unidirectional causality from urbanization to electricity consumption and economic growth was found but the long-run empirical findings revealed urbanization impedes growth - a situation that has policy implications. The study highlights that though urbanization is a good predictor of Nigeria's economic growth, however, the adjustment of the energy portfolio to…

The effect of air pollution on the environment, economic and health of the people in the affected countries cannot be overemphasized. This paper investigates large scale air pollution elimination to remove pollutants that are already in existence in the environment. This method involves the use of Environmental Drones (E-drones) to autonomously monitor the air quality at a specific location. The E-drone flies up to a predetermined height (Ealtitude) every hour, measures the air pollutants at that location, implements on-board pollution abatement solutions for pollutants above the recommended threshold, and then flies back down to its location on the ground. The advantages of this system is its ability to measure air pollution concentration of CO 2 , CO, NH 3 , SO 2 , PM, O 3 and NO 2 , detect when they are too high, and implement on-board pollution abatement solutions as needed. This system's novelty lies in the fact that it not only detects when there is excessive pollution, but it also automatically deals with and abates the detected air pollution above earth. When multiple…

In this paper, the literature on Islamic endowment funds (awqaf) was surveyed. The data suggest that banking, accountability, law, and norms constitute most of the coverage in this body of literature. The finance topic, with 35% coverage, dominated the literature, whereas history (with 6% coverage) recorded the least interest. In this sample, the second most popular theme was related to economic development (25% coverage). Also discovered was that 59% of the papers employed a normative approach, and the balance adopted an empirical approach. A direct benefit of this study is that it provides input for government policy and directions for future researchers.

Researchers have shown considerable interest in finding a sustainable, low cost, and readily available substitute for the commercial calcium oxide (CaO) catalyst. In this work, raw chicken eggshell was modified by boiling and calcination at 900 °C for 3 h. The x-ray diffraction characterization revealed that while the proportion of CaCO 3 in the raw and boiled samples was found to be 79.3 % and 99.2 % respectively, the CaCO 3 had been converted to 63.8 % CaO and CO 2 in the calcined sample. This was due to the thermal decomposition during calcination. The outcome of the infrared spectroscopy showed that the raw and boiled chicken eggshell presented a similar absorption profile with peaks at 1 394 cm −1 , 873 cm −1 , and 712 cm −1 , which were as a result of the presence of asymmetric stretch, out-of-plane bend, and in-plane bend vibration modes. The major peaks presented by the calcined sample at 3642 cm −1 can be attributed to the OAH stretching vibration and bending hydroxyl groups present in Ca(OH) 2 . The Brunauer-Emmett-Teller surface areas for the raw, boiled and calcined…

Date ( Phoenix dactylifera L.) seeds are seen as good drug to cure rheumatoid arthritis and asthma in Moroccan traditional medicine. The present research aimed to study the anti-inflammatory effect, of methanol extract of different date seed varieties using membrane stabilizing effect, nitric oxide radical scavenging activity, inhibition of protein denaturation, carrageenan-induced paw edema and croton oil induced ear edema. The polyphenolic profile was examined using HPLC-DAD. Rutin, quercetin, p -coumaric and caffeic acids were the main among the analysed phenolic compounds. Concerning the anti-inflammatory activity, the analysed date seed were significantly effective in scavenging nitric oxide free radical, in stabilisation of erythrocyte membrane and possessed a high anti denaturation effect. In agreement with this finding, date seed exhibited a profound ability to reduce paw and ear swelling induced by carrageenan and croton oil respectively. The biochemical parameters showed that date seed are able to reduce the erythrocyte sedimentation rate (ERS) and C-reactive protein (CRP)…

Copper Oxide/Carbon (CuO/C) nanocomposites were developed through the green method using the leaf extract of Adhatoda vasica at room temperature. Here, the leaf extract serves as a capping agent, reducing agent and a source of carbon for the formation of nanocomposites. As we know, this is the first article on the synthesis of CuO/C nanocomposites using this leaf extract. The nanocomposites were prepared by mixing the copper sulphate pentahydrate solution with the plant extract under certain conditions. The synthesized material was characterized by XRD, UV-Visible, FTIR, FE SEM, EDS, XPS and TGA. The results revealed that the synthesized material is a composite of copper oxide and functionalized graphene-like carbon. The SEM images indicated that the CuO/C nanoflakes had an average thickness of 7–11nm. Further, the composites were examined for antifungal activity and antibacterial activity. The nanocomposites showed significant antibacterial activity against the pathogenic bacterial strains Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus and…

PVDF was prepared by compression molding, and its phase content/structure was assessed by WAXD, DSC, and FTIR-ATR spectroscopy. Next, PVDF samples were aged in bioethanol fuel at 60 °C or annealed in the same temperature by 30 ─ 180 days. Then, the influence of aging/annealing on thermal stability, thermal degradation kinetics, and lifetime of the PVDF was investigated by thermogravimetric analysis (TGA/DTG), as well as the structure was again examined. The crystallinity of ~41% (from WAXD) or ~49% (from DSC) were identified for unaged PVDF, without significant changes after aging or annealing. This PVDF presented not only one phase, but a mixture of α -, β - and γ -phases, α - and β -phases with more highlighted vibrational bands. Thermal degradation kinetics was evaluated using the non-isothermal Ozawa–Flynn–Wall method. The activation energy ( E a ) of thermal degradation was calculated for conversion levels of α = 5 ─ 50% at constant heating rates (5, 10, 20, and 40 °C min ─1 ), α = 10% was fixed for lifetime estimation. The results indicated that temperature alone does not…

Additive manufacturing has attracted increasing attention worldwide, especially in the healthcare, biomedical, aerospace, and construction industries. In Malaysia, insufficient acceptance of this technology by local industries has resulted in a call for government and local practitioners to promulgate the development of this technology for various industries, particularly for biomedical products. The current study intends to frame the challenges endured by biomedical industries who use 3D printing technology for their manufacturing processes. Qualitative methods, particularly in-depth interviews, were used to identify the challenges faced by manufacturing firms when producing 3D printed biomedical products. This work was able to identify twelve key challenges when deploying additive manufacturing in biomedical products and these include issues related to binder selection, poor mechanical properties, low-dimensional accuracy, high levels of powder agglomeration, nozzle size, distribution size, limited choice of materials, texture and colour, lifespan of materials, customization of…

In this study, a Methyl Green (MG) dye pollutant was separated by Mobil Composition Matter No. 41 (MCM-41) in a fixed-bed continuous column with investigated three parameters, namely a bed height (2–6 cm), initial MG concentration (10–30 mgL -1 ) and a process flow rate (0.8–1.6 mL min −1 ). Results indicated that the highest bed capacity of 20.97 mg/g was obtained with respective to optimal values such as; 6 cm for a column height, 0.8 mL min −1 for flow rate, and an initial MG concentration 20 mgL -1 . Furthermore, a quantity of the adsorbed pollutant decreased as the flow rate increased, while increasing the initial MG concentration yielded the opposite effect. The column apparatus was performed properly at the low flow rate, whereas both the breakthrough and exhaustion time increased with the bed depth. Thomas and Yoon-Nelson models were applied for predicting the breakthrough curves and calculating the characteristic factors of the laboratory fixed-bed adsorption column, which were beneficial for process design. Based on regression coefficient analyses, results of employing the…

Cellulases are enzymes that hydrolyse cellulose and related cellu-oligosaccharides derivatives. Its applications are enormous but high cost of production is the bottle-neck against the utilization of cellulase in industries. Therefore, this study investigated the isolation, purification and characterization of cellulase produced by Aspergillus niger cultured on Arachis hypogaea shells. The crude cellulase enzyme was produced by A. niger through submerged fermentation process using A. hypogaea shells as a carbon source. The optima fermentation conditions were determined by varying different parameters. The crude cellulase was purified through ammonium sulphate precipitation, dialysis and gel-filtration chromatography. The molecular weight was estimated using sodium dodecyl sulphate polyacrylamide gel electrophoresis. The effects of pH and temperature on the activity of the purified cellulase were investigated. The study revealed that the: optimal production of crude cellulase was achieved at incubation period of 120 h, pH 4, temperature 40 °C, and inoculum size of 13 × 10 5 CFU/ml.…

BACKGROUND: Improperly disposed medicines could adversely affect the environment and increase the risk of drug misuse or accidental poisoning. OBJECTIVE: To evaluate the disposal practices of unused and expired medicines among the general population in Bandung, Indonesia. METHOD: This was a descriptive cross-sectional survey conducted among 497 respondents in Bandung, Indonesia. Data were collected through interviews using a prevalidated structured questionnaire. Descriptive statistics were calculated using the Statistical Package for Social Science (SPSS) version 23. Ethics approval was obtained. MAIN OUTCOME MEASURE: General public knowledge and attitude regarding unused and expired medication disposal practice. RESULTS: Approximately 95% of the respondents had unused medicines stored in their homes, with nonsteroidal anti-inflammatory drugs (NSAIDs), vitamins/nutritional supplements, and antibiotics were the most common types of medicines left unused. The majority of the respondents checked the expiration date of the drugs before purchasing (72.8%). The most common disposal…

Despite the widespread availability and increasing use of cyberlearning environments, there remains a need for more research about their usefulness in undergraduate education, particularly in STEM education. The process of evaluating the usefulness of a cyberlearning environment is an essential measure of its success and is useful in assisting the design process and ensuring user satisfaction. Unfortunately, there are relatively few empirical studies that provide a comprehensive test of the usefulness of cyberlearning in education. Additionally, there is a lack of standards upon whose usefulness evaluators agree. In this research, we present multiple user studies that can be used to assess the usefulness of a cyberlearning environment used in Computer Science and Software Engineering courses through testing its usability and measuring its utility using user interface and user experience evaluations. Based on these assessments, we propose an evaluation framework to evaluate cyberlearning environments. To help illustrate the framework utility and usability evaluations, we explain them…

This study explores the impacts of COVID-19 on household energy use. Some of these impacts are associated with longer-term energy demand changes and some could just be temporary. The study intends to present the results of a small pilot study conducted in China, by addressing household energy use. The samples are from 352 households and particularly focus on primary energy use in three periods of pre-pandemic (and pre-lockdown), start of COVID-19 outbreak and lockdown, and post lockdown. Each period is identified as a timeframe of 2.5 months, from November 2019 to late June 2020. The samples of this study highlight the primary implications of energy use, some that are understood as interim changes and some that may appear to be more prolonged. The results from the study highlight a variety of impacts on household energy use as well as prolonged impacts on transportation use. The primary household energy use are assessed in six fundamental elements of (1) transportation for commuting and leisure (for both private and public modes), (2) cooking, (3) entertainment, (4) heating and…

The Covid-19 pandemic lead Italy to undertake a severe lockdown for almost two months. All of a sudden, the lives of Italians were forced to shift in accordance with the regulations issued by government. This change in the lives of Italians can be mirrored by an adjustment in food consumer behaviour that, consequently, brought about a transition in the whole supply chain. This paper gives an overview of the recent changes in consumption patterns that occurred due to the Italian lockdown, and how evolutions in behaviour are intertwined with the evolution of the main food supply chains. Many of the events here depicted are likely to last far beyond the crisis and affect the subsequent evolution of food consumption in Italy. The Italian retail supply chain successfully adapted to the big shift in consumption. Despite purchases for essential items having increased, no stockout harmed the food security of Italians. Out-of-home consumption moved inside houses giving space to home meal preparation and comfort food. Home delivery has been the most important element in this context, as it…

This study analyzed the compound growth rate (CGR) and the contributions of yield and area to cassava production output in Nigeria. During the period, TE1970 - TE2018, production followed an upward trajectory from 9.3 million tonnes (1970) to 59.5 million tonnes (2018) while yield oscillated between 7.9tonnes/ha (TE2014) and 11.9tonnes/ha (TE2010). At this period, the CGR per year for yield declined (-0.2%), harvested area increased (10.9%) and production increased (10.6%). The decomposition analysis for the period revealed that, increase in output was largely due to expansion of harvested area (152%) while the interaction between area and yield effect declined production output by 45.8%. Regrettably, during the period, cassava yield also declined production output by 5.8%. The study also found that harvested area has the highest instability index (11.8). In order to further increase and sustain cassava production in Nigeria, intense planting of high yield cassava stems instead of solely expanding cropped area is recommended.

The implementation of this research consists of 2 (two) aspects: the making and testing of bio-briquettes called technological aspects and economic analysis called economic aspects. Bio-briquettes is made from cashew nutshell waste obtained from Southeast Sulawesi, Indonesia. It is followed by pyrolysis, which is carried out in a simple batch type reactor by heating using liquefied petroleum gas (LPG). The bio-briquettes product has a calorific value of 29.49 MJ/kg, moisture content of 5.3%, ash content of 4.96%, volatile substances content of 17.16%, and carbon content of 72.62%, which meets the universally accepted bio-briquettes standard (SNI 016235-2000), Japanese, English and ISO 17225. The bio-briquettes product is suitable as an energy source. The economic analysis of the cashew nutshell was analyzed to determine its economic feasibility. For the bio-briquettes production capacity in 2,000 tons/year, cashew nut shell-briquettes products can be sold at 1,052,878 USD/year. The total production cost is USD842,304/year. The net profit is of USD147,402/year. The cost of LPG for…

Agricultural management methods affect organic compounds in the soil. The aim of this study was to characterize humic and fulvic acids using infrared spectroscopy and nuclear magnetic resonance (NMR) in aggregates collected from areas under different crop and soil management systems. Soil samples were collected at depths of 0.00–0.10 m in a trial set up in 1989 with four management systems (no-till, no-till with chiseling every three years, disk harrowing and heavy disking) under two production systems (succession and rotation). In the laboratory, the soil was sieved and separated into two fractions: particle size of 2 mm or more, and less than 2 mm. From each of the samples an aliquot was extracted and the humic and fulvic acids purified for FTIR, UV-VIS and NMR- 1 H analysis. The results obtained showed that the structural characterization of the humic and fulvic acid fractions were linked to organic matter left on the soil surface, especially where the agricultural system involved species diversity. Aggregates ≥2 mm produce higher NMR, UV-VIS and FTIR spectral magnitudes in…

The accelerated population and industrial development have caused an extensive increase in the use of plastic products. Since polyethylene degrades slowly generating poisonous compounds, therefore, elimination of plastic from the environment is the prerequisite requirement today. Biodegradation of plastics seems to be a convenient and effective method to curb this problem. In view of this, the present study focuses on LDPE degradation capability of bacterial strain Pseudomonas aeruginosa ISJ14 (Accession No. MG554742) isolated from waste dump sites. Further, the stability of 16S rDNA of the isolate was determined by applying bioinformatics tools. For biodegradation studies, the polyethylene films were incubated with the culture of P. aeruginosa ISJ14 in two different growth medium namely Bushnell Hass broth (BHM) and Minimal Salt medium (MSM) for 60 days at 37 °C on 180 rpm. In addition, hydrophobicity and viability of bacterial isolate along with quantification of total protein content was also done. The microbial degradation was confirmed by surface modification and formation of…