Miracle-dz/UniFAR-FTUs huggingface dataset:
Modelling and performance analysis of a single stage open absorption heat pump system in aspen plus using aqueous LiBr and HCOOK: A waste moist heat recovery application

Open absorption heat pump (OAHP) system is more viable option to recover waste heat from moist gas as compared to the traditional condensation methods. This promising technology has great potential for latent heat recovery from moist gas, drying process in paper and other industrial heating applications. This study presents the process modelling and comparative analysis of OAHP system in Aspen Plus using two different solutions by adopting part regeneration technique. The promising potassium formate-water (HCOOK/H2O) which has lower causticity, lower costs and better crystallization characteristics is used as an alternative to the caustic lithium bromide-water (LiBr/H2O) solution in this study. Process model of the system is established in Aspen Plus and, the properties validity is confirmed with published experimental and Engineering Equation Solver (EES) library data. A detailed comparative parametric study is carried out to evaluate the effect of influencing parameters on coefficient of performance (COP), water recovery (φ) and heat recovery (ζ) efficiencies. The performance of OAHP system is found to be very similar using different concentrations as 2.13 COP value for 50% LiBr/H2O and 2.19 for 70% HCOOK/H2O solution over design conditions. Similarly, φ is found to be 0.701, 0.688 while ζ as 0.716 and 0.705 for both the absorbents. Moreover, the system’s operational concentration range is 45-61.3% for LiBr/H2O and 55-82.1% for HCOOK/H2O at 135 °C regeneration heat input. Potassium formate solution having quite similar properties to the aqueous lithium bromide is also confirmed to have similar performance trends using 50% and 70% concentrations.
Anthelmintic Activity of Nigella sativa against Caenorhabditis elegans

Increasing resistance against classical anthelmintic drugs makes discovering new anthelmintic compounds from natural plants important. Nigella sativa (N. sativa) is used as a medicinal plant overall the world and is known to have anthelmintic activity. Caenorhabditis elegans (C. elegans), a common cost-effective model organism that is easily maintained, is useful to determine the anthelmintic activity of new compounds derived from natural products. In our study we aimed to evaluate through toxicity assays the nematocidal activity of N. sativa on C. elegans during its larval and adult stages. Different concentrations of N. sativa oil (900, 450 and 270 mg/mL) were tested and toxicity assessments were done under stereomicroscope by counting the number of surviving nematodes. This study showed that N. sativa essential oil significantly decreases survival of C. elegans in both larval and adult stages at 900 mg/mL final concentration. Larval-stage worms were more sensitive to N. sativa essential oil than were adults. We recommend further studies on other effects of N. sativa on C. elegans after removing the toxic compound(s) from the extract. The further discovery of N. sativa essential oil compounds responsible for anthelmintic activity and determination of their mechanisms of toxicity can pave the way toward new medicines.
Community density of grassland effect on soil carbon dynamics: Field survey and analyses from a 45‐year natural recovery time‐sequence on the Loess Plateau, China

Community density of grassland has obvious impacts on the absorption, sequestration, and accumulation of soil carbon (C). However, few studies have examined the effect of community density on soil C dynamics and their internal driving forces after cropland abandonment. Here, we synthesized the responses of soil C to community density of grassland over a 45‐year time‐sequence along a natural restoration time sequence. The results showed that the soil C content during the late‐successional period was greater than that during the early‐successional period, that is, annual C storage rates for the first sequence (1–15 years) for the 0–60 cm depth profiles were −0.34, −0.27, −0.15 to 0.02 Mg‐C ha−1 yr−1, in the ≤10, 11–20, 21–30, and >30 community densities. And the third sequence (31–45 years) presented values that were 79.28% and 44.60% greater than those of the initial stage of vegetation restoration (CK) for the 0–20 and 0–60 cm profiles, respectively. The increased soil C storage rates of the late‐successional sequence were associated with both increased aboveground production and root biomass for this sequence and the presence of multiple species, especially Leguminosae and Gramineae species, with developed roots. Overall, the effects of community density on soil C were regulated by the recovery time, root mass, and species genera. Furthermore, our results suggest that soil may still be a carbon source even after 15 years of the abandonment restoring, and high community density may greatly increase C capture and storage rates in abandoned lands. The findings enhance the understanding of soil C sequestration and accumulation responses to community density following long‐term natural vegetation succession, providing support for estimating and predicting the regional C budget and global C cycle.
The Impact of Distance Learning on the Psychology and Learning of University Students during the Covid-19 Pandemic

COVID-19 saw the world face a serious global health crisis which had a negative impact on all sectors of life especially education. Educational institutions across the globe were forced to temporarily close and use distance education as an alternative to face-to-face teaching. The current study explored the impact of the sudden transition from face-to-face learning to distance learning on students' psychology and learning. Four hundred and one (N=401) undergraduate students from the University of Petra, Jordan were surveyed using a user-designed online questionnaire. Results highlighted negative impacts of distance education on both participant's psychology and learning during the Covid-19 pandemic. More specifically, results showed that first and second year students and those with lower computer skills reported the highest negative psychological effects (i.e., feeling anxious, bored and nerves). Further first-year students and those with lower computer skill levels reported a negative impact on learning (i.e., experiencing lethargy and laziness when taking online lectures, poor focus and inability of being self-reliant when learning) by distance education when compared with students in their third and fourth year or those with higher and average computer skills. Finally, this paper discusses recommendations and implications for future distance learning. © 2021 Eskisehir Osmangazi University. All rights reserved.
Change of Processes in the COVID-19 Scenario: From Face-to-Face to Remote Teaching-Learning Systems

COVID-19 has accelerated digital transformation in teaching-learning environments. Universities based on face-to-face models have had to quickly adapt their processes to ensure the success of remote teaching-learning systems in the last months. The growing demand for technological resources has meant an effort to understand the requirements and variables that affect students’ acceptance, intention to use, and adoption of these tools. This study aims to analyze students’ acceptance of online processes adopted by universities because of the COVID-19 scenario. Although this study is based on a Technology Acceptance Model (TAM), it also considers other factors, such as perceived efficiency and satisfaction. A questionnaire was built and distributed to 313 students. The data were processed using the Structural Equation Model (SEM) method. The results indicate that 30.7% of the students improved their views of remote education using online systems. However, 49.9% of students do not believe that face-to-face teaching-learning education will be replaced by virtual teaching-learning education in the long term. Our findings confirm that the enriched TAM model built provides a useful theoretical approach to understanding and explaining users’ acceptance of remote learning environments when there is a need to rapidly migrate from face-to-face to online teaching-learning processes.
Antifungal and plant growth promoting activity of Trichoderma spp. against Fusarium oxysporum f. sp. lycopersici colonizing tomato

Fusarium wilt, incited by Fusarium oxysporum f. sp. lycopersici (FOL), causes serious production losses of tomato (Solanum lycopersicum L.) plants. Biological control, using an antagonistic of Trichoderma species, is a bio-rationale and an alternative method to synthetic pesticides against most phytopathogens. The present study was undertaken to evaluate the effects of T. harzianum and/or T. viride in reducing Fusarium wilt and to determine the relationship between disease severity and plant growth promoting traits of these species. Trichoderma viride exhibited better phosphate solubilization and production of cellulases, ligninases, chitinases, proteases, hydrogen cyanide (HCN), siderophores and indole acetic acid (IAA) than T. harzianum. For field assessment, five treatments with three replicates were used. The field was inoculated with the wilt fungus (FOL). Both Trichoderma spp. used were applied as a seed treatment, mixed in the soil, and FOL inoculated soil served as the untreated control. During the two consecutive years, seed treatment with T. viride exhibited the least disease severity, the highest physiological activity, the highest biochemical and antioxidant contents, and tomato plants treated with it exhibited the best growth and yield. It was concluded that Trichoderma viride can potentially be used to reduce Fusarium wilt and promote plant growth and yield in commercial tomato production.
Prevalence of depression in older adults living in Ecuador and contributing factors: a population-based study

Objective To estimate the prevalence of depression in the older population of Ecuador and explore the independent associations of key socio-demographic and health-related factors with moderate/severe depression.Methods A cross-sectional study was conducted using a national database. The outcome variable was estimated using the Short Form of the Geriatric Depression Scale. A cut-value of >9 was used to ascertain the outcome variable. We conducted bivariate and logistic regression analysis.Results The study sample consisted of 5 235 subjects, with a median age of 70 years, 53.5% were female, and 44.9% of the sample was living in rural areas. Our study found a prevalence of any depression of 35.4%. Individuals were classified as having mild depression (1 239, 23.7%), moderate depression (457, 8.7%), and severe depression (156, ~3%). The prevalence of moderate/severe depression was of 11.7%. Among socio-demographic factors, no education (OR=3.69 [95% CI: 1.35-11.94]), Afro-Ecuadorian race (OR= 2.1 [1.03-4.06]), living alone (OR=2.37 [1.67-3.31]), perception of insufficient income (OR= 3.56 [2.14-6.38]), and suffering physical abuse (OR=2.33 [1.59-3.36]) remained statistically significant. Among health-related factors, drinking alcohol (OR=0.27 [0.08-0.66]), exercise (OR=1.68 [1.24-2.31]), incontinence (OR=2.00 [1.54-2.59]), lower perception of hearing (OR=2.19 [1.41-3.32]), cancer (OR=1.90 [1.00-3.51]), and being functionally dependent (OR=1.59 [1.22-2.08]) remained statistically significant.Conclusions Our investigation brings light to an important public health problem in Ecuador. Addressing depression and its contributing factors may help to improve the quality of life and long-term health outcomes in Ecuador’s growing older population.
LONG-TERM FOOD RESTRICTION AND DIABECON ADMINISTRATION AMELIORATES ALLOXAN-INDUCED HYPERGLYCEMIA, THYROID DYSFUNCTION, AND OXIDATIVE STRESS IN RAT.

Objective: The comparative effects of food restriction (FR), Diabecon treatment (DT) and their combined therapy (FR+DT) were studied in the regulation of alloxan-induced diabetes mellitus, alterations in thyroid hormones (TH) and oxidative stress. Methods: Young diabetic rats were either kept on 50% FR and/or DT (2 gm/Kg body weight) for two months and then alterations in serum glucose, insulin, TH concentrations, hepatic glycogen and pancreatic antioxidants along with oxidative stress markers were evaluated. Results: Significantly increased serum glucose, tissue stress markers with decreased TH, hepatic glycogen (P<0.0001 for all) and pancreatic antioxidants (P<0.05-0.001) were observed in diabetic rats. Rats kept on different therapies exhibited significant (P<0.05) improvements than diabetic rats in all studied parameters. FR+DT group showed a significantly more decrease in serum glucose (P<0.05) that FR or DT group, while in other parameters improvement was found to be more or less equally improved in all treated groups. Conclusion: FR appeared to mimic the effects of Diabecon in most of the indices. However, FR+DT appears to be more effective. Possibly both therapies ameliorate diabetes and oxidative stress following some common metabolic pathways.
Employees’ psychological capital and innovation outputs: the roles of job crafting and proactive personality

ABSTRACT This study examined a moderated mediation model in which the job crafting of employees mediates the relationship between employees’ psychological capital (PsyCap) and their innovation outputs, and this mechanism is moderated by employees’ proactive personality. The results produced by structural equation modelling with a sample of 653 employees in Vietnam confirmed the above relationships. The results produced by fuzzy-set qualitative comparative analysis with the same data set demonstrated that none of those personality-based resources (PsyCap, job crafting, and proactive personality) served as sufficient conditions for innovation outputs. Instead, their combinations did. The study findings confirm the overarching roles of those personality-based resources, especially in combinations, of employees in their innovation outputs.
Diagnostic performance of CT-derived resting distal to aortic pressure ratio (resting Pd/Pa) vs. CT-derived fractional flow reserve (CT-FFR) in coronary lesion severity assessment

Background Computed tomography-derived fractional flow reserve (CT-FFR) has emerged as a promising non-invasive substitute for fractional flow reserve (FFR) measurement. Normally, CT-FFR providing functional signiﬁcance of coronary artery disease (CAD) by using a simplified total coronary resistance index (TCRI) model. Yet the error or discrepancy caused by this simplified model remains unclear. Methods A total of 20 consecutive patients with suspected CAD who underwent CTA and invasive FFR measurement were retrospectively analyzed. CT-FFR and CT-(Pd/Pa)rest values derived from the coronary CTA images. The diagnostic performance of CT-FFR and CT-(Pd/Pa)rest were evaluated on a per-vessel level using C statistics with invasive FFR<0.80 as the reference standard. Results Of the 25 vessels eventually analyzed, the prevalence of functionally signiﬁcant CAD were 64%. The Youden index of the ROC curve indicated that the best cutoff value of invasive resting Pd/Pa was 0.945 for identifying functionally significant lesions. Sensitivity, speciﬁcity, negative predictive value, positive predictive value and accuracy were 85%, 91%, 92%, 83% and 88% for CT-(Pd/Pa)rest and 85%, 58% 69%, 78% and 72% for CT-FFR. Area under the receiver-operating characteristic curve (AUC) to detect functionally signiﬁcant stenoses of CT-(Pd/Pa)rest and CT-FFR were 0.87 and 0.90. Conclusions In this study, the results suggest CT-derived resting Pd/Pa has a potential advantage over CT-FFR in triaging patients for revascularization.
Aerodynamic Performance of a Flyable Flapping Wing Rotor With Passive Pitching Angle Variation

This article is based on an experimental study on the aerodynamic performance of a flapping wing rotor (FWR) and enhancement by passive pitching angle variation (PPAV) associated with powered flapping motion. The PPAV (in this article, 10o–50o) is realized by a specially designed sleeve-pin unit as part of a U-shape flapping mechanism. Through experiment and analysis, it is found that the average lift produced by an FWR of PPAV is >100% higher than the baseline model, the same FWR of a constant pitching angle 30o under the same input power. It is also noted that the lift–voltage relationship for the FWR of PPAV is almost linear and the aerodynamic efficiency is also over 100% higher than the baseline FWR when the input voltage is under 6 V. The aerodynamic lift or efficiency of the FWR of PPAV can be also increased significantly by reducing the weight of the wings. An FWR model is fabricated and achieved vertical take-off and free flight powered by 9 V input voltage. The mechanism of PPAV function provides a feasible solution for aerodynamic improvement of a bioinspired FWR and potential application to micro air vehicles.
Identifying and Characterizing Subsurface Tropical Instability Waves in the Atlantic Ocean in Simulations and Observations

Recent observations in the Pacific Ocean suggest that, apart from tropical instability waves (TIWs) at the surface, there also exist subsurface tropical instability waves (subTIWs), which can alter vertical mixing. However, the extent to which subTIWs impact mixing and heat flux is still unknown. Moreover, studies on subTIWs have been conducted exclusively in the Pacific. Here, we show the presence of subTIWs in the Atlantic for the first time, using mooring observations. Analyzing 16 years of simulations of a comprehensive, global, high-resolution ocean model, we characterize subTIWs in the Atlantic with regard to their spatial and temporal variability and investigate their influence on vertical mixing. We find subTIWs in the Atlantic between 40 and 90 m depth in both the model and observations. Furthermore, the model results reveal that unlike TIWs, subTIWs frequently also occur south of the Equator in the Atlantic Ocean. We show that subTIWs induce an oscillating multilayer shear structure, suggesting subTIWs to destabilize the mean flow and thereby induce mixing. This is strongest north of the ocean shows the potential of subTIWs to destabilize the mean and thereby inducing shown by positive values of reduced shear squared above thermocline. We show the relevance of in relation to TIWs using a composite analysis of strong TIW and The results suggest great importance of simultaneous occurrence of both TIWs and for vertical mixing and fluxes in the thermocline.
THE EFFECT OF WORK MOTIVATION AND WORK ENVIRONMENT ON EMPLOYEE PERFORMANCE MEDIATED BY JOB SATISFACTION (AT PT ICI PAINTS INDONESIA)

The effect of work motivation and work environment on employee performance is mediated by job satisfaction (at PT. Ici Paint Indonesia). The research used is descriptive analysis and causality of the population. The respondents of this research were 105 population samples, this analysis method used path analysis, coefficients, and inter-dimensional analysis. The results here show (H1) Work motivation has a positive and significant effect on job satisfaction, (H2) Work environment on job satisfaction has a positive and significant effect, (H3) Work motivation on employee performance has a positive and significant effect, (H4) Work environment on employee performance positive and significant effect, (H5) Job satisfaction on employee performance has a positive and significant effect, (H6) Work motivation on performance through job satisfaction has a positive and significant effect, (H7) the work environment on employee performance through job satisfaction has a positive and significant effect. The independent variable (x) is work motivation (x1) and work environment (x2). The dependent variable is job satisfaction (y1) and performance (y2), from the research it is proven from the hypothesis that has been researched and calculated through the Spss 23 application.
MITRAGYNINE PERCENTAGES OF VARIOUS KRATOM VARIANTS SEIZED IN INDONESIA: A QUANTITATIVE ANALYSIS USING LIQUID CHROMATOGRAPHY-PHOTO DIODE ARRAY DETECTOR

Objective: This study details the determination of mitragynine in various kratom samples using the thin-layer chromatography (TLC) technique and validation of analytical methods for quantifying the concentration of mitragynine in various kratom samples using liquid chromatography with photodiode array detector (LC-PDA). Methods: TLC technique using n-hexane: ethyl acetate: ammonia 25% (30: 15: 1 v/v/v) was applied to isolate mitragynine from kratom samples. Several interesting spots obtained were visualized under UV light at 254 nm. Samples were also prepared with organic solvent extraction directly prior to LC analysis (non-isolation method of preparation) to quantify the concentration of mitragynine. Mobile phases used were acetonitrile (MP A) and 0.1% formic acid in water (MP B). Samples and standards were run by gradient elution with a flow rate of 0.3 ml/min, detection using PDA detector at 254 nm. Results: Mitragynine was successfully isolated from kratom samples in Rf 0.50 by TLC system applied. The validation of analytical methods for mitragynine passed the acceptance criteria as described by UNODC Guidance. The concentration of mitragynine in various kratom samples seized in Indonesia ranged from 0.37%-1.70% (%w/w). Conclusion: Both TLC and LC analytical methods could be applied to determine and quantify the concentration of mitragynine in each examined sample, respectively.
Supplementary material to "Dissolution of a submarine carbonate platform by a submerged lake of acidic seawater"

Abstract. Submarine sinkholes are found on carbonate platforms around the world. They are thought to form and grow when groundwater interactions generate conditions corrosive to carbonate minerals. Because their morphology can restrict mixing and water exchange, the effects of biogeochemical processes can accumulate such that the sinkhole water properties considerably diverge from the surrounding ocean. Studies of sinkhole waters can therefore reveal new insights into marine biogeochemical cycles, thus sinkholes can be considered as 'natural laboratories' where the response of marine ecosystems to environmental variations can be investigated. We conducted the first measurements in recently discovered sinkholes on Luymes Bank, part of Saba Bank in the Caribbean Netherlands. Our measurements revealed a plume of gas bubbles rising from the seafloor in one of the sinkholes, which contained a constrained body of dense, low-oxygen ([O2] = 60.2 ± 2.6 μmol · kg−1), acidic (pHT = 6.24 ± 0.01) seawater that we term the 'acid lake'. Here, we investigate the physical and biogeochemical processes that gave rise to and sustain the acid lake, the chemistry of which is dominated by the bubble plume. We determine the provenance and fate of the acid lake’s waters, which we deduce must be continuously flowing through. We show that the acid lake is actively dissolving the carbonate platform, so the bubble plume may provide a novel mechanism for submarine sinkhole formation and growth. It is likely that the bubble plume is ephemeral and that other currently non-acidic sinkholes on Luymes Bank have previously experienced ‘acid lake’ phases. Conditions within the acid lake are too extreme to represent coming environmental change on human timescales but in some respects reflect the bulk ocean billions of years ago. Other Luymes Bank sinkholes host conditions analogous to projections for the end of the 21st century and could provide a venue for studies on the impacts of anthropogenic CO2 uptake by the ocean.