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Fulltext Safety and quality preservation of starfruit (Averrhoa carambola) at ambient shelf life using synergistic pectin-maltodextrin-sodium chloride edible coating

Mohd Suhaimi NI, Mat Ropi AA, Shaharuddin S

Heliyon, 2021 Feb;7(2):e06279.
PMID: 33681497 DOI: 10.1016/j.heliyon.2021.e06279

The demand for fresh, safe, and healthy fruits by consumers has increased, which concurrently occurs with an increase in initiatives on reducing food wastage. Starfruit consists of good nutrition and valuable sensory attributes, but its shelf life is short and can only be preseved for a few days at ambient storage. This research was conducted to determine the effectiveness of synergistic edible coatings (pectin [Pe] and maltodextrin [M] and 100, 200, and 300 ppm of sodium chloride [SC]) on the quality and safety criterion of starfruits throughout a shelf life analysis of 14 days at ambient temperature. Consumer acceptability of the edible-coated starfruit was also evaluated. The coating process was performed using a dipping method. The uncoated (control) and coated samples were evaluated for the characteristics of weight, pH, total soluble solids (TSS), water activity, color, texture, microbial growth, FTIR, and sensory evaluation. From the results, the starfruit coated with Pe + M + 100 ppm SC had a significantly lower weight-loss trend compared to the other samples. On day 14, pH of the coated starfruits were 3.02, 3.14, and 3.31 for 100, 200, and 300 ppm of SC, respectively, were found to be significantly different (p < 0.05) from the control (pH 3.49). The control had a significantly higher value of total soluble solids (6.00 ⁰Brix) compared to the coated starfruits (6.00, 5.47, and 5.33 ⁰Brix, respectively). The coated samples have significantly higher values of firmness than control especially in initial days of storage. It was observed that Pe + M + 100 ppm SC could minimize the spoilage of fruits by reducing the growth of yeast and mold, as well as bacteria, up to 0.86 and 2.02 log CFU/ml, respectively. FTIR results confirmed the presence of the coating on the starfruit. In the sensory evaluation, no significance different (p > 0.05) were obtained for all the sensory attributes and overall acceptability for day 0 and 3. In conclusion, starfruit coated with synergistic Pe + M + 100 ppm SC appeared to be the best sample in extending its shelf life and maintaining the physicochemical characteristics of starfruits up to more than 14 days.
Fulltext Cellular and molecular profiles of anterior nervous system regeneration in Diopatra claparedii Grube, 1878 (Annelida, Polychaeta)

Ahmad Nazri MUI, Mahmud MH, Saidi B, Mat Isa MN, Ehsak Z, Ross O, et al.

Heliyon, 2021 Feb;7(2):e06307.
PMID: 33681499 DOI: 10.1016/j.heliyon.2021.e06307

The polychaete Diopatra claparedii Grube, 1878 is among those organisms successfully carrying out full body regeneration, including the whole nervous system. Thus, D. claparedii potentially can be regarded for the nervous system regeneration (NSR) study. However, data on the property of its nervous system and the NSR profile are still lacking. In this study, we investigated the morphology of D. claparedii anterior nervous system (ANS) and examined the cellular and molecular profiles on its early anterior NSR. The nervous system of D. claparedii consists of a symmetry brain with nerves branching off, circumpharyngeal connectives that connect the brain and nerve cord as well as obvious segmental ganglia. Moreover, we identified changes in the cellular condition of the ganglionic cells in the regenerating tissue, such as the accumulation of lysosomes and lipofuscins, elongated mitochondria and multiple nucleoli. Furthermore, mRNA of tissues at two regenerating stages, as well as intact tissue (non-regenerating), were sequenced with Illumina sequencer. We identified from these tissues 37,248 sequences, 18 differential expressed proteins of which upregulated were involved in NSR with noelin-like isoform X2 turned up to be the highest being expressed. Our results highlight the cellular and molecular changes during early phase of NSR, thus providing essential insights on regeneration within Annelida and understanding the neurodegenerative diseases.
Fulltext Impact of religiosity on purchase intentions towards counterfeit products: investigating the mediating role of attitude and moderating role of hedonic benefits

Yaakop AY, Hafeez HM, Faisal MM, Munir M, Ali M

Heliyon, 2021 Feb;7(2):e06026.
PMID: 33644436 DOI: 10.1016/j.heliyon.2021.e06026

This study was aimed at exploring the impact of religiosity on purchase intention towards counterfeit products by investigating the mediating role of consumer attitude. This study investigated religiosity as an independent variable, attitude towards counterfeit as a mediator while predicting the purchase intentions of the consumers. A self-administered questionnaire using a five-point Likert scale was used to collect data from the sample of 420 respondents who were from twin cities (Rawalpindi and Islamabad) of Pakistan. Structural equation modeling technique was used to achieve the set objectives. The results reveal a statistically significant effect of religiosity along with the significant mediating role of consumer attitude and the significant moderating role of hedonic benefits while predicting the purchase intentions of the consumers. This study also provides important insights for the researchers and the practitioners.
Fulltext A review of augmented reality systems and their effects on mental workload and task performance

Jeffri NFS, Awang Rambli DR

Heliyon, 2021 Mar;7(3):e06277.
PMID: 33748449 DOI: 10.1016/j.heliyon.2021.e06277

Augmented Reality (AR) systems have been shown to positively affect mental workload and task performance across a broad range of application contexts. Despite the interest in mental workload and the increasing number of studies evaluating AR use, an attempt has yet to be made to identify the relationship between the effects of AR on mental workload and task performance. This paper seeks to address this gap in AR technology literature. With a better understanding how AR affects mental workload and task performance, researchers and developers can design more effective AR systems. 34 articles investigating the effects of the use of AR systems were selected for the review. A positive correlation was found between effects on mental workload and effects on task performance: if the effect on mental workload is positive, then the effects on task performance are more likely to be positive as well, and vice versa. Effectiveness of AR systems were shown to be influenced by the type of AR display device used, relevance and timeliness of content, information presentation, user characteristics and task characteristics. Additionally, the paper addresses the use of the concept of mental workload and limitations in current literature.
Fulltext Coping with COVID-19 and movement control order (MCO): experiences of university students in Malaysia

Kamaludin K, Chinna K, Sundarasen S, Khoshaim HB, Nurunnabi M, Baloch GM, et al.

Heliyon, 2020 Nov;6(11):e05339.
PMID: 33134570 DOI: 10.1016/j.heliyon.2020.e05339

This study examined how university students in Malaysia coped with the psychological impact of the COVID-19 pandemic and restrictions on movement (also known as MCO). A total of 983 students participated in a survey conducted online between April 20 and May 24, 2020. The psychological impact was measured using Zung's Self-Rating Anxiety Scale (SAS). The students were assessed on the usage of adaptive (humanitarian and seeking social support) and maladaptive coping strategies (acceptance and mental disengagement). The results showed that the students used maladaptive coping strategies more than adaptive coping strategies to deal with anxiety caused by the pandemic and the effect of restriction of movement. Seeking social support and acceptance coping strategies were significantly associated with the level of anxiety. The student's gender, age, ethnicity, level and type of study, and living arrangement were associated with coping strategies. The students' selection of coping strategies mirrors typical Asian culture, that is, submissiveness. The study proposes several practical and professional suggestions to address students' mental health issues.
Fulltext Coronavirus pandemic and spirituality in southwest Nigeria: A sociological analysis

Olonade OY, Adetunde CO, Iwelumor OS, Ozoya MI, George TO

Heliyon, 2021 Mar;7(3):e06451.
PMID: 33786389 DOI: 10.1016/j.heliyon.2021.e06451

Introduction: The coronavirus pandemic outbreak is wreaking much havoc across the globe, with many nations shutting down their economy and social life with the hope of flattening the curve while health practitioners are also gearing efforts in providing a cure for it. Part of the coronavirus challenges is the various spiritual undertones attributed to it in many quarters. Hence, this study seeks to understand the various spiritual undertones attributed to the coronavirus incidence in southwest Nigeria.
Methodology: This paper examined the coronavirus pandemic and spirituality sociologically in southwest Nigeria, using secondary and primary data. Secondary data includes a review of literature, social media comments, official records, and newspaper reports. Primary data entails using google form (questionnaire) circulated via social media with 221 responses retrieved and analyzed using the frequency distribution tables and bar charts. Also, a one-sample t-test was used for further statistical analysis.
Results: Findings show that rather than attributing coronavirus incidence to spirituality alone, most of the respondents also see it as a public health concern, and precautionary measures should adhere. They see the government ban on social gathering, which affected the religious houses as the right thing to do and not solely targeted as religious houses. However, most believe that religious houses provide 'essential' emotional and spiritual support to the people. Respondents also believe they can get their healing from their place of worship even if infected with the coronavirus.
Conclusion: Based on the findings it was recommended that religious organizations should source valid data so that policy-makers can make informed decisions. Also, there is a need to have an accurate record of the number of infected persons and death rates to know the right time to ease lockdown and lift the social gathering measures. There should also be a place for easy and free testing for people. This will help the government ascertain the number of infected persons, reduce the associated fear with the pandemic, and lessen the people's economic, social, and religious effects.
Fulltext Choices of chromatographic methods as stability indicating assays for pharmaceutical products: A review

Chew YL, Khor MA, Lim YY

Heliyon, 2021 Mar;7(3):e06553.
PMID: 33855234 DOI: 10.1016/j.heliyon.2021.e06553

Stability indicating assay describes a technique which is used to analyse the stability of drug substance or active pharmaceutical ingredient (API) in bulk drug and pharmaceutical products. Stability indicating assay must be properly validated as per ICH guidelines. The important components in a stability indicating assay include sensitivity, specificity, accuracy, reliability, reproducibility and robustness. A validated assay is able to measure the concentration changes of drug substance/API with time and make reliable estimation of the quantity of the degradation impurities. The drug substance is separated and resolved from the impurities. Pros and cons of HPLC, GC, HPTLC, CE and SFC were discussed and reviewed. Stability indicating assay may consist of the combination of chromatographic separation and spectroscopic detection techniques. Hyphenated system could demonstrate parallel quantitative and qualitative analysis of drug substances and impurities. Examples are HPLC-DAD, HPLC-FL, GC-MS, LC-MS and LC-NMR. The analytes in the samples are separated in the chromatography while the impurities are chemically characterised by the spectroscopy in the system. In this review, various chromatographic methods which had been employed as stability indicating assays for drug substance and pharmaceutical formulation were systematically reviewed, and the application of hyphenated techniques in impurities characterisation and identification were also discussed with supporting literatures.
Fulltext Impact of intrapersonal and interpersonal emotional intelligence and self-directed learning on academic performance among pre-university science students

Okwuduba EN, Nwosu KC, Okigbo EC, Samuel NN, Achugbu C

Heliyon, 2021 Mar;7(3):e06611.
PMID: 33869848 DOI: 10.1016/j.heliyon.2021.e06611

Provision of equitable access to university education is the primary goal of pre-university education. Academically weak students stand to benefit more from pre-university program. However, available literature on effectiveness of the program revealed that high percentage of students still fail pre-university courses. Although the role of psycho-emotional factors on student academic performance has been highlighted, mechanism through which psycho-emotional factors impact on academic performance of pre-university science students is still not clear to offer adequate insights for proper intervention program. Therefore, we examined the pre-university students' academic performance in sciences in relation to Emotional Intelligence (EI) (Interpersonal EI and Intrapersonal EI) and Self-directed Learning (SDL). Specifically, a correlational study design was conducted to measure and gauge the level of relationships amongst Interpersonal EI, Intrapersonal EI, SDL and academic performance of pre-university students. The participants were 443 Nigerian students enrolled in pre-university science program. Students' self-report on EI and SDL were gathered and analyzed using SPSS 26 and AMOS 24. Exploratory and confirmatory factor analysis were performed to determine cross-cultural validity of the instruments in the Nigerian context. After controlling for gender and age, the hierarchical regression analysis reveals that student academic performance was positively predicted by perceived Interpersonal and Intrapersonal EI, whereas self-directed learning has an inconsistent predictive impact at different steps in the model. Overall, the predictor variables were able to explain substantial proportion of students' academic performance in pre-university program. Insightful suggestions were made.
Fulltext Does quality stimulate customer satisfaction where perceived value mediates and the usage of social media moderates?

Uzir MUH, Jerin I, Al Halbusi H, Hamid ABA, Latiff ASA

Heliyon, 2020 Dec;6(12):e05710.
PMID: 33367128 DOI: 10.1016/j.heliyon.2020.e05710

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. Collected data were CB-SEM (AMOS-v24) and SPSS. The findings showed PQ and SQ have positive effects on CS; SQ affects, but PQ does not affect CPV. CPV has a mixing mediating effect on SQ and CS relationship and PQ and CS relationship. Importantly, the positive impact of PQ, SQ and CPV is greater on customers who exhibit higher social media use. The conceptual framework was buttressed by EDT theory. The study contributed to contextual and theoretical knowledge in regards to home appliances. The practicing managers can collect an insight of customer satisfaction for their business.
Fulltext Reduction of the acidity and peroxide numbers of tengkawang butter (Shorea stenoptera) using thermal and acid activated bentonites

Darmawan MA, Muhammad BZ, Harahap AFP, Ramadhan MYA, Sahlan M, Haryuni, et al.

Heliyon, 2020 Dec;6(12):e05742.
PMID: 33364505 DOI: 10.1016/j.heliyon.2020.e05742

Tengkawang fat (Shorea stenoptera), from an indigenous plant of the Kalimantan forest, has excellent potential as an alternative source of vegetable fat because it has a high level of fatty acids composition. Activated natural bentonite can be used as a bleaching agent to improve the quality of tengkawang fat. This research aims to reduce the acidity, peroxide number values and identify the physicochemical properties (fatty acid composition, nutrients, and thermal) of tengkawang butter. Initially, tengkawang samples from Nanga Yen and Sintang were pre-treated using the degumming process with 1% phosphoric acid and the neutralization process with a 1 M NaOH 10% w/w solution. The results show that the acidity (mg NaOH/g) of the tengkawang fat samples was reduced from 11.00 to 3.36 when using bentonite activated at 200 °C. The bentonite activated with 0.5 M HCl reduced the acidity to 3.61. The peroxide number (meq O2/kg) of the tengkawang fat samples was reduced from 9.45 to 4.84 and 3.47 by bleaching with thermal-activated and acid-activated bentonites, respectively. Peroxide value correlates with β-carotene content. The smaller of the β-carotene content, the smaller the peroxide value. The acidity, peroxide number, and iodine number values from tengkawang fat after treatment adhere to the SNI 2903: 2016 standard. The main content of fatty acids in tengkawang fat is palmitic acid, stearic acid, and oleic acid. These results show that both products are suitable for the food industry in terms of the acid and peroxide numbers. The application of this research results will assist local people in increasing the economic value of the product from tengkawang plant, which is an indigenous plant from Kalimantan.
Fulltext Ranking negative emissions technologies under uncertainty

Ng WY, Low CX, Putra ZA, Aviso KB, Promentilla MAB, Tan RR

Heliyon, 2020 Dec;6(12):e05730.
PMID: 33364497 DOI: 10.1016/j.heliyon.2020.e05730

Existing mitigation strategies to reduce greenhouse gas (GHG) emissions are inadequate to reach the target emission reductions set in the Paris Agreement. Hence, the deployment of negative emission technologies (NETs) is imperative. Given that there are multiple available NETs that need to be evaluated based on multiple criteria, there is a need for a systematic method for ranking and prioritizing them. Furthermore, the uncertainty in estimating the techno-economic performance levels of NETs is a major challenge. In this work, an integrated model of fuzzy analytical hierarchy process (AHP) and interval-extended Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) is proposed to address the multiple criteria, together with data uncertainties. The potential of NETs is assessed through the application of this hybrid decision model. Sensitivity analysis is also conducted to evaluate the robustness of the ranking generated. The result shows Bioenergy with Carbon Capture and Storage (BECCS) as the most optimal alternative for achieving negative emission goals since it performed robustly in the different criteria considered. Meanwhile, energy requirement emerged as the most preferred or critical criterion in the deployment of NETs based on the decision-maker. This paper renders a new research perspective for evaluating the viability of NETs and extends the domains of the fuzzy AHP and interval-extended TOPSIS hybrid model.
Fulltext Antioxidative attributes of rice bran extracts in ameliorative effects of atherosclerosis-associated risk factors

Tan XW, Kobayashi K, Shen L, Inagaki J, Ide M, Hwang SS, et al.

Heliyon, 2020 Dec;6(12):e05743.
PMID: 33376820 DOI: 10.1016/j.heliyon.2020.e05743

Oxidative stress, chronic inflammation, dyslipidemia, hyperglycemia, and shear stress (physical effect) are risk factors associated with the pathogenesis of atherosclerosis. Rice bran, a by-product of rice milling process, is known to house polyphenols and vitamins which exhibit potent antioxidant and anti-inflammatory properties. Through recent emerging knowledge of rice bran in health and wellness, the present study was aimed to assess the ameliorative effects of rice bran extracts (RBE) derived from Japanese colored rice varieties in modulating risk factors of atherosclerosis via in vitro and in vivo study models. Pre-treatment of lipopolysaccharide (LPS)-stimulated murine J774A.1 macrophage-like cells with RBE alleviated nitric oxide (NO) overproduction and downregulated gene expressions of pro-inflammatory modulators: tumor necrosis factor-α (TNF-α), interleukin (IL)-α (IL-1α), IL-1β, IL-6, and inducible nitric oxide synthase (iNOS). In addition, RBE also significantly attenuated LPS-stimulated protein expressions of iNOS, TNF-α, IL-1α, and IL-6 in J774A.1 macrophage-like cells as compared to non-treated LPS control group. In in vivo, 12 weeks of RBE dietary supplementations significantly reduced (p < 0.05) total cholesterol, triglycerides, and pro-atherogenic oxidized LDL/β2-glycoprotein I (oxLDL/β2GPI) complexes at plasma levels, in high fat diet (HFD) induced low density lipoprotein receptor knockout (Ldlr-/-) mice. En face pathological assessments of murine aortas also revealed significant reductions by 38% (p < 0.05) in plaque sizes of RBE-supplemented HFD mice groups as compared to non RBE-supplemented HFD control mice group. Moreover, gene expressions of aortic (iNOS, TNF-α, IL-1β) and hepatic (TNF-α, IL-1α, IL-1β) pro-inflammatory modulators were also downregulated in RBE-supplemented mice groups. Present study has revealed the potent health attributes and application of RBE as a dietary supplement to attenuate risks of inadvertent oxidative damage and chronic inflammation underlying the pathogenesis of atherosclerosis. Intrinsically, present preliminary findings may provide global health prospects for future dietary implementation of RBE in management of atherosclerosis.
Fulltext MHD radiative nanofluid flow induced by a nonlinear stretching sheet in a porous medium

Jafar AB, Shafie S, Ullah I

Heliyon, 2020 Jun;6(6):e04201.
PMID: 32637680 DOI: 10.1016/j.heliyon.2020.e04201

In this article, we numerically investigate the influence of thermal radiation and heat generation on the flow of an electrically conducting nanofluid past a nonlinear stretching sheet through a porous medium with frictional heating. The partial differential equations governing the flow problems are reduced to ordinary differential equations via similarity variables. The reduced equations are then solved numerically with the aid of Keller box method. The influence of physical parameters such as nanoparticle volume fraction ϕ, permeability parameter K, nonlinear stretching sheet parameter n, magnetic field parameter M, heat generation parameter Q and Eckert number Ec on the flow field, temperature distribution, skin friction and Nusselt number are studied and presented in graphical illustrations and tabular forms. The results obtained reveal that there is an enhancement in the rate of heat transfer with the rise in nanoparticle volume fraction and permeability parameter. The temperature distribution is also influenced with the presence of K, Q, R and ϕ. This shows that the solid volume fraction of nanoparticle can be used in controlling the behaviours of heat transfer and nanofluid flows.
Fulltext Antioxidant and anti-inflammatory properties of Erythroxylum cuneatum alkaloid leaf extract

Li LS, Chiroma SM, Hashim T, Adam SK, Mohd Moklas MA, Yusuf Z, et al.

Heliyon, 2020 Jun;6(6):e04141.
PMID: 32637674 DOI: 10.1016/j.heliyon.2020.e04141

Erythroxylum cuneatum (E. cuneatum) which belongs to Erythroxylaceae family is a tropical flowering plant from the genus of Erythroxylum. It is used in Malaysia and Thailand's traditional medicines, yet there is limited scientific reports on its medicinal value. This study aimed at exploring the antioxidative and anti-inflammatory properties of E. cuneatum alkaloid leaf extract. The alkaloid extract was obtained through Soxhlet heat extraction method, while the antioxidantive properties were assessed via 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, ferric reducing antioxidant power (FRAP) and xanthine oxidase inhibition (XOI) assays. Further, anti-inflammatory property of the extract was evaluated on rat's model of carrageenan induced paw model of edema via physical measurements and histology. The extract exhibited antioxidant activity with an EC50 value of 1482 μg/ml in the DPPH radical scavenging assay, an EC1 value of 2191 μg/ml in the FRAP assay and 10.15 ± 6.20% in the XOI assay. Rats pretreated with the extract have shown dose dependent decrease in paw edema when compared to non-treated group of rats. The highest dose (50 mg/kg) of extract exhibited similar effects to aspirin in terms of reducing paw thickness, leucocytes infiltration and disruption of collagen. In conclusion, the E. cuneatum alkaloid leaf extract possesses both antioxidative and anti-inflammatory properties suggesting its potentials for future development of antioxidant and anti-inflammatory drugs.
Fulltext Carboxymethyl cellulose-based polyelectrolyte as cationic exchange membrane for zinc-iodine batteries

Tangthuam P, Pimoei J, Mohamad AA, Mahlendorf F, Somwangthanaroj A, Kheawhom S

Heliyon, 2020 Oct;6(10):e05391.
PMID: 33150216 DOI: 10.1016/j.heliyon.2020.e05391

The aim of this research is an evaluation of polyelectrolytes. In the application of zinc-iodine batteries (ZIBs), polyelectrolytes have high stability, good cationic exchange properties and high ionic conductivity. Polyelectrolytes are also cost-effective. Important component of ZIBs are cation exchange membranes (CEMs). CEMs prevent the crossover of iodine and polyiodide from zinc (Zn) electrodes. However, available CEMs are costly and have limited ionic conductivity at room temperature. CEMs are low-cost, have high stability and good cationic exchange properties. Herein, polyelectrolyte membranes prepared from carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVA) are examined. It is seen that an increase in the ratio of PVA leads to enhanced ionic conductivity as well as increased iodine and polyiodide crossover. ZIBs using polyelectrolytes having 75:25 wt.% CMC/PVA and 50:50 wt.% CMC/PVA show decent performance and cycling stability. Due to their low-cost and other salient features, CMC/PVA polyelectrolytes prove they have the capacity for use as cation exchange separators in ZIBs.
Fulltext Comparison between conventional human energy measurement and physical human energy measurement methods in wetland rice production

Elsoragaby S, Yahya A, Nawi NM, Mahadi MR, Mairghany M, Muazu A, et al.

Heliyon, 2020 Nov;6(11):e05332.
PMID: 33294651 DOI: 10.1016/j.heliyon.2020.e05332

Measurement of human energy expenditure during crop production helps in the optimization of production operations and costs by identifying steps which that can benefit from the use of appropriate mechanization technologies. This study measures human energy expenditure associated with all 6 major rice (Oryza sativa L.) cultivation operations using two measurement methods-i.e. conventional human energy expenditure method and direct measurement with a Garmin forerunner 35 body media. The aim of this study was to provide a detailed comparison of these two methods and document the human energy costs in a manner that will identify steps to be taken to help optimize agricultural practices. Results (mean + 95%CL) revealed that the total human energy expenditure obtained through the conventional method was 25.5% higher (33.3 ± 1 versus 26.6 ± 1.3) in transplanting and 26.1% higher (30.3 ± 1.9 versus 24.0 ± 2.1) than the human energy expenditure recorded using the Garmin method in broadcast seeding method. Similarly, during the harvesting operation, the conventional measurement and Garmin measurement methods differed significantly, with the conventional method the human energy expenditure was 89.9% higher (3.2 ± 0.4 versus 1.68 ± 0.2) in the fields using the transplanting and 88.7% higher (3.3 ± 0.5 versus 1.8 ± 0.3) in the fields using the broadcast seeding than the human energy expenditure recorded using the Garmin method. When using Garmin method, the human energy expenditure in the case of using the midsize combine harvester was 13.49% lesser (592.4 ± 67.2 versus 522.0 ± 75.1) than the case of using conventional one. Results based on heart rate also indicated that operations such as tillage were less intensive (72 ± 3.3 bpm) compared with operations such as chemicals spraying (135 ± 4 bpm). Although we did not have a criterion measure available to determine which method was the most accurate, the Garmin measurement gives an estimate of actual physical human energy expended in performing a specific task with consider all conditions and thus more information to aid in identifying critical operations that could be optimized and mechanized.
Fulltext Price perception and price appearance on repurchase intention of Gen Y: do brand experience and brand preference mediate?

Yasri Y, Susanto P, Hoque ME, Gusti MA

Heliyon, 2020 Nov;6(11):e05532.
PMID: 33294680 DOI: 10.1016/j.heliyon.2020.e05532

The study examines the effect of price perception and price appearance on Gen Y's repurchase intention towards snack products of small and medium-sized enterprises (SMEs), along with the mediating roles of consumers' brand experience and preference. A survey method for data collection in the study used with a structured questionnaire, in which the respondents were requested to give their responses to the experiment conducted on local specialty snack products produced by SMEs. Covariance-based structural equation modeling (CB-SEM) was used to analyze the hypothesized relationships in the research model. The findings show that all the direct effects in the proposed model have a significant effect, except for the relationship between price perception and brand preference that there is no significant effect. Similarly, the mediating roles of consumer brand experience and consumer-based brand preference proved to have a significant effect. Finally, the implications of this study will be discussed further.
Complex permittivity and power loss characteristics of α-Fe2O3/polycaprolactone (PCL) nanocomposites: effect of recycled α-Fe2O3 nanofiller

Mensah EE, Abbas Z, Azis RS, Ibrahim NA, Khamis AM, Abdalhadi DM

Heliyon, 2020 Dec;6(12):e05595.
PMID: 33305050 DOI: 10.1016/j.heliyon.2020.e05595

The development of microwave absorbing materials based on recycled hematite (α-Fe2O3) nanoparticles and polycaprolactone (PCL) was the main focus of this study. α-Fe2O3 was recycled from mill scale and reduced to nanoparticles through high energy ball milling in order to improve its complex permittivity properties. Different compositions (5% wt., 10% wt., 15% wt. and 20% wt.) of the recycled α-Fe2O3 nanoparticles were melt-blended with PCL using a twin screw extruder to fabricate recycled α-Fe2O3/PCL nanocomposites. The samples were characterized for their microstructural properties through X - ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). The complex permittivity and microwave absorption properties were respectively measured using the open ended coaxial (OEC) probe and a microstrip in connection with a vector network analyzer in the 1-4 GHz frequency range. An average α-Fe2O3 nanoparticle size of 16.2 nm was obtained with a maximum imaginary (ε") part of permittivity value of 0.54 at 4 GHz. The complex permittivity and power loss values of the nanocomposites increased with recycled α-Fe2O3 nanofiller content. At 2.4 GHz, the power loss (dB) values obtained for all the nanocomposites were between 13.3 dB and 14.4 dB and at 3.4 GHz, a maximum value of 16.37 dB was achieved for the 20 % wt. nanocomposite. The recycled α-Fe2O3/PCL nanocomposites have the potential for use in noise reduction applications in the 1-4 GHz range.
Flux model development and synthesis optimization for an enhanced GO embedded nanocomposite membrane through FFD and RSM approach

Abdul Wahab MS, Abd Rahman S, Abu Samah R

Heliyon, 2020 Nov;6(11):e05610.
PMID: 33305039 DOI: 10.1016/j.heliyon.2020.e05610

A two-level full factorial design was used to analyze several factors involved in PSF-GO-Pebax thin film nanocomposite membranes development. Permeate flux was chosen as a single response for four possible factors: Pebax selective layer concentration, amount of GO load to Pebax selective layer, Pebax-GO selective layer thickness, and amount of GO load to PSF substrate. The study is aimed at factors interaction and contribution towards the highest permeation flux via FFD and RSM approach. R2 obtained from the ANOVA is 0.9937 with Pebax concentration as the highest contributing factor. Pebax concentration-amount of GO load to PSF substrate is the only interaction contributing to the highest flux. A regression analysis concluded the study with model development and an optimized condition for the membrane design.
Fulltext Methods and variables in Electrical discharge machining of titanium alloy - A review

Pramanik A, Basak AK, Littlefair G, Debnath S, Prakash C, Singh MA, et al.

Heliyon, 2020 Dec;6(12):e05554.
PMID: 33344787 DOI: 10.1016/j.heliyon.2020.e05554

Titanium alloys are difficult to machine using conventional methods, therefore, nonconventional processes are often chosen in many applications. Electrical discharge machining (EDM) is one of those nonconventional processes that is used frequently for shaping titanium alloys with their respective pros and cons. However, a good understanding of this process is very difficult to achieve as research results are not properly connected and presented. Therefore, this study investigates different types of EDM processes such as, wire EDM, die-sink EDM, EDM drill and hybrid EDM used to machine titanium alloys. Machining mechanism, tool electrode, dielectric, materials removal rate (MRR), and surface integrity of all these processes are critically analysed and correlated based on the evidence accessible in literature. Machining process suffer from lower material removal rate and high tool wear while applied on titanium alloys. Formation of recast layer, heat affected zone and tool wear is common in all types of EDM processes. Additional challenge in wire EDM of titanium alloys is wire breakage under severe machining conditions. The formation of TiC and TiO2 are noticed in recast layer depending on the type of dielectrics. Removal of debris from small holes during EDM drilling is a challenge. All these restricts the applications EDMed titanium alloys in high-tech applications such as, aerospace and biomedical areas. Most of these challenges come up due to extraordinary properties such as, low thermal conductivity, high melting point and high hardness, of titanium alloys. Though hybrid EDM has been introduced and there is some work on simulation of EDM process, further developments in EDM of this alloy is required for widening the application of this methods.

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