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Reliability and validity of instrument on academic enhancement support for student-athlete using Rasch measurement model
Get PDFThe purpose of this article is to develop and validate an instrument on Academic Enhancement Support for Malaysian student-athletes. The instrument development process began earlier in previous research's stages. Thirty-five questionnaires were distributed to Malaysia Public University student-athletes who competed at the university and state levels. It took a week to collect data, with a 100% return rate and one damaged questionnaire removed. Winstep version 3.69.1.11 was used to conduct three analyses: item-person reliability and separation index, statistical fit, and standardised residual correlation for item dependent. Cronbach's alpha of 0.96 indicates high reliability, with all items displaying a positive value for item polarity. Thirty items were identified as being misfit, five of which were removed and fifteen of which were revised. In the final analysis, ten pairs of items were dictated to be redundant, and ten items were eliminated following selection. In total, 15 items were removed from the instrument, leaving 82 items in the validated version. In conclusion, the instrument developed is a valid instrument capable of validating the student-perception athlete's of the support necessary for academic advancement during actual study
A review on the effects of various elemental doping and nanostructuring of β-FeSi2/Si composites on the thermoelectric performance enhancement
No full textThermoelectric device is a transformative technology for renewable energy generation. It is designed in a small compact feature with a quiet mechanism and has no gas emission, enabling it to conserve energy and preserve the global environment. Iron disilicide (β-FeSi2/Si) composite materials prepared by eutectoid reaction is found promising for thermoelectric applications. The strategies to enhance the thermoelectric properties of these composites are mainly by conducting band structure engineering such as elemental doping and nanostructure engineering. This article reviews the effects of elemental doping and nanostructuring of β-FeSi2/Si composite materials. Mn and Co were found to be the most common dopants due to their contribution to carrier mobility and carrier concentration. Other dopant elements such as Al, introduced point defects on the composite structure that is effective in lowering thermal conductivity. P was also found to be effective on both electronic and lattice contribution of thermal conductivity. Furthermore, in thin films structure, flatter surface is highly recommended rather than the crystallinity of films to enhance carrier mobility and suppress thermal conductivity. Thus, the way to optimize β-FeSi2/Si composite materials were discovered by the significant number of studies on refinement of composite structure into nanoscale. From these studies, electrical conductivity value was significantly enhanced while reducing its thermal conductivity and Seebeck coefficient value. The deterioration of Seebeck coefficient is yet to be improved hence was estimated possible by introducing doping mechanisms. Therefore, this review concludes some potential strategies for improving Seebeck coefficient while simultaneously increasing electrical conductivity and decreasing thermal conductivity towards enhancing its thermoelectric performance
Evaluation of the occurrence of antibiotics at different treatment stages of decentralised and conventional sewage treatment plants
Get PDFAntibiotics are widely used in human society and are consequently found in sewage treatment plants. However, information regarding the fate of antibiotics in decentralised sewage treatment plants is limited. Therefore, this study monitored and compared four frequently prescribed antibiotics (ampicillin, ciprofloxacin, erythromycin and sulfamethoxazole) in each stage of four conventional treatment plants (three extended aerations and one conventional activated sludge) and two decentralised treatment plants (two Imhoff tanks) in Johor Bahru district between December 2018 and August 2019. The findings revealed that ampicillin, ciprofloxacin, erythromycin and sulfamethoxazole were detected in most wastewater samples, including influent, secondary effluent, final effluent and sewage sludge samples. The antibiotic concentrations in the aqueous and sludge phases ranged from 4.2 to 2690 ng/l and 1.7 to 317.4 ng/g, respectively. Ampicillin and sulfamethoxazole were effectively removed by extended aeration and conventional activated sludge plants (> 75% reduction), erythromycin was effectively removed in IT plants (> 85% reduction) and ciprofloxacin could not be removed effectively by any systems (< 30% reduction). Statistical analysis showed that the approximate relationships between the removal of antibiotics and several wastewater parameters existed. A detailed antibiotic mass flow was conducted in extended aeration and Imhoff tank plants. An estimate of 115.72 g, 202.25 g, 170.55 g and 213.21 g of ampicillin, ciprofloxacin, erythromycin and sulfamethoxazole, respectively, were discharged annually. The mass balance analysis indicated that biodegradation was the major route for the removal of all antibiotics studied. Meanwhile, sorption was only responsible for minor removal of ciprofloxacin, erythromycin and sulfamethoxazole
Identification of earthworm for sustainable agriculture - a review
Get PDFEarthworms are considered as a friend of farmers. These fretful worms improve the air and water content in the dirt. When a worm dies, it decomposes into nitrogen and benefits the farmers. Nowadays, they are common prey for chemical contamination. Also, the agricultural farming today uses high quantity of pesticides to protect the crops from pest and diseases. By spraying pesticides, the lifecycle of earthworm is affected. This paper focuses on detailed study of earthworm and its importance on farming. It also deals with impact of chemicals on earthworm and its side effects. This paper discusses about the identification of earthworm in farmland and various methods for enhancing the growth of worms. This paper also focuses on the detailed description of various extraction methodologies of earthworms from the farms and gives the detailed analysis of merits and demerits of each extraction methods
Oral participation practices in classroom among university students in Afghanistan
Get PDFThis study aimed at exploring factors affecting classroom participation among students in the English department of Laghman University, Afghanistan. More precisely, this research discovered factors related to teachers and class-size that hinder students’ practice of oral participation in the classroom. In collecting the data, this study employed mixed-method research with concurrent design. An adapted questionnaire and a semi-structured interview have been used as the data collection instrument of this study. An online survey questionnaire was conducted with 110 respondents. In addition, a semi-structured interview was conducted with five of the respondents at the English Department of Laghman University. The data from the questionnaire was descriptively analyzed through using statistical package for social science (SPSS), and the semi-structured interview data were thematically analyzed and interpreted. The findings revealed that classsize related factor is the first influential factor in affecting oral participation among students and it is due to having large number students in a class. Teacher’s related factor is the second influential factor that affects the oral participation of students. Majority claimed that teachers’ approach, behavior, and qualification have prominent impact on their level of oral participation. Based on the finding, it can be seen that class-size related, and teachers’ factors affected oral participation of the students at the English Department of Laghman University. It is recommended that the Ministry of Higher Education of Afghanistan strive to decrease the number of students in each class and enforce teachers in implementing a student-centered learning approach while teaching
Enzymes immobilized polymeric supports for wastewater treatment application: a short review
No full textMicro-pollutants, with a growing number of hazardous contaminants being introduced into both human and natural ecosystems, have become a major topic of rising environmental concern and the biological method is an up-and-coming wastewater treatment technique in late decades. This review focuses on enzyme immobilization in biological wastewater treatment, in which enzymes are used to biodegrade and remove various types of pollutants. The synthesis of different kinds of polymer substrates, their biocompatibility, stability, reusability and application for the immobilization of enzymes, and their biochemical as well as biotechnological applications which employment of enzymes immobilization for different wastewater treatment processes are reviewed. Various cases of wastewater biotreatment are described, such as removal of pigments and colour in textile industry wastewater, refractory organics wastewater, as well as nitrogen and phosphorous wastewater treatment. The review concludes with a brief discussion of potential research directions in enzyme immobilization on polymeric supports for wastewater treatment application
The effects of aeration and mixotrophy by acetate and pyruvate on the growth parameters in Scenedesmus obliquus
No full textThe mixotrophic growth of microalgae offers great potential as an efficient strategy for increasing biomass production. In this study, Scenedesmus obliquus was used to investigate the biomass growth conditions and biochemical parameters of algae cells in autotrophic and mixotrophic conditions with and without aeration. It was found that mixotrophic cultivation of algae cells by 50 mM acetate had a strong effect on increasing fresh weight, chlorophyll a, b, carotenoid, astaxanthin, protein, and lipid content (with 20, 4.6, 8.7, 60, 4.5, 4.8, and 18.4-fold, respectively) in comparison to the control cultures. Mixotrophy by pyruvate also increased the amount of all mentioned parameters. The best concentration of pyruvate was found to be 50 mM, but the effects of acetate were stronger. Aeration in a short time (2 h) had a different effect on mixotrophic cultures with acetate and pyruvate. It declined the effect of acetate on increasing the fresh weight and the amount of other biochemical parameters. Unlike the acetate treatment, aeration had an enhancement effect on increasing the fresh weight and biochemical parameters content in 50 and 100 mM pyruvate treatments. In the control cultures, the saturated acid, caprylic acid (C8:0) (40%), and the polyunsaturated eicosapentaenoic acid (EPA, C20:5 n3) (17.5%) showed higher percentages. Mixotrophy caused a decrease in the percentage of saturated fatty acids (SFAs) and, on the other hand, an increase in the percentage of unsaturated fatty acids (UFAs). EPA was the main fatty acid in the mixotrophic condition. Aeration in the phototrophic condition decreased the percentage of SFAs, while increasing that of UFAs. Aeration under mixotrophic conditions increased UFAs in both acetate and pyruvate-treated cultures. The results suggest that aeration could be an important factor in interaction with other algae growth conditions. It should be noted that acetate had generally better effects on the biomass quality of S. obliquus without aeration
Validity of performance factors used in recent studies on heat transfer enhancement by surface modification or insert devices
No full textBased on literature survey, the performance factors were used in 62 articles which have been published in 2021 in International Journal of Heat and Mass Transfer, International communications in Heat and Mass Transfer, International Journal of Thermal Sciences and Applied Thermal Engineering, to evaluate the heat transfer enhancement by geometry modification or insertion of tapes, wires or turbulence promoters under identical pumping power. However, the validity of the performance factors was not examined yet. The heat transfer rate in a periodic fully developed region of a circular duct with periodic annular baffle plates was numerically obtained. Comparing the heat transfer rate with that of a circular smooth duct, the validity of the performance factors used in previous studies was examined. It was found that the performance factors used in the previous studies are not valid for the evaluation of heat transfer enhancement. Furthermore, this paper shows that the direct comparison of heat transfer rates without the assumptions of equal surface area and the equal temperature difference is suitable for the evaluation of heat transfer enhancement
The effect of modification psychomotor tasks in the virtual reality on cadence and behavioural responses of cycling
No full textVirtual reality is an alternative tool to provide a safe and competitive environment, especially for training and competitions. This study aims to evaluate the effects of modified psychomotor tasks in the virtual reality on the alpha/beta ratio, power output, heart rate, and cadence. The participants are recruited among national development cyclists from National Sport School. The environment of virtual reality was modified from the available virtual reality TACX smart trainer system. The one-way multivariate of variance (MANOVA) identified the effects of the five different levels of psychomotor task (independent variables) in virtual reality on multiple variables of physiological responses. The MANOVA results indicate a statistically significant multivariate main effect for the five levels of task difficulty in road cycling, when jointly considering on the variables of alpha/beta ratio, power output, heart rate, and cadence. The multivariate general linear model for univariate ANOVA results demonstrates a significant difference between subject on alpha/beta ratio and cadence. Significant task pairwise differences were obtained for cadence between Task 1 and both Tasks 2 and 5. The results suggest human’s interaction with virtual reality, specifically during the psychomotor task during road cycling. The significant effects on the joint physiological responses ensured that evaluation of the experiment on developed task difficulty in virtual reality was practical, applicable and can be modified when required for training or assessment. The involvement of cognitive functions in response to behavioural mechanism merits further investigation and are deferred for future work
Microbiomes of biohydrogen production from dark fermentation of industrial wastes: current trends, advanced tools and future outlook
Get PDFBiohydrogen production through dark fermentation is very attractive as a solution to help mitigate the effects of climate change, via cleaner bioenergy production. Dark fermentation is a process where organic substrates are converted into bioenergy, driven by a complex community of microorganisms of different functional guilds. Understanding of the microbiomes underpinning the fermentation of organic matter and conversion to hydrogen, and the interactions among various distinct trophic groups during the process, is critical in order to assist in the process optimisations. Research in biohydrogen production via dark fermentation is currently advancing rapidly, and various microbiology and molecular biology tools have been used to investigate the microbiomes. We reviewed here the different systems used and the production capacity, together with the diversity of the microbiomes used in the dark fermentation of industrial wastes, with a special emphasis on palm oil mill effluent (POME). The current challenges associated with biohydrogen production were also included. Then, we summarised and discussed the different molecular biology tools employed to investigate the intricacy of the microbial ecology associated with biohydrogen production. Finally, we included a section on the future outlook of how microbiome-based technologies and knowledge can be used effectively in biohydrogen production systems, in order to maximise the production output