19672 research outputs found
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The optimization of effective parameters for electrodeposition of reduced graphene oxide through Taguchi method to evaluate the charge transfer
No full textIn the present work, the Taguchi experimental design technique, an effective and elegant tool, is employed to design and optimize a system for improving the quality of the products as well as discovering significant factors and optimize the parameters for electrodeposition of graphene oxide, in order to achieve low charge transfer resistance from the minimum number of experiments. Reduced graphene oxide (rGO) was prepared via electrochemical process. Electrochemical Impedance Spectroscopy was employed to evaluate the effects of variables on charge transfer resistance. Graphene oxide concentration, pH, scan rate and number of cycles were chosen as important effective parameters. Charge transfer resistance was minimized by measuring the signal-to-noise (S/N) ratio of the factors. Analysis of variance (ANOVA) was also employed to monitor the parameter influence and optimize the process. © 2019 Elsevier Lt
Functionalized cellulose beads with activated carbon Fe3O4/CoFe2O4 for cationic dye removal
No full textModified regenerated cellulose beads functionalized with activated carbon (AC), as well as magnetic cellulose beads of AC-Fe3O4 and AC-CoFe2O4, were synthesized. The AC was further used as adsorbent for the removal of cationic methylene blue (MB) dye from aqueous solution. The magnetic cellulose beads possessed a high magnetic response to an external magnetic field and their ease of recovery could be facilitated with the aid of a magnetic field. The synthesized adsorbents were characterized using a Field Emission Scanning Electron Microscope (FESEM), as well as by energy dispersive X-ray (EDX) spectrometry and thermogravimetric analysis (TGA). In comparison with the synthesized magnetic cellulose beads, the maximum adsorption capacity of the adsorbent beads assisted with AC, AC-Fe3O4 and AC-CoFe2O4 was of 54, 53 and 50 mg/g, respectively. The kinetic study of the adsorption of MB dye onto the adsorbents was performed at different parameters (initial dye concentration and temperature). The kinetics of the adsorption fit well with the pseudo-second-order model. © 2019 Editura Academiei Romane. All rights reserved
Dispensation of antiretroviral therapy and methadone maintenance therapy at the same facility in a low‐barrier setting linked to optimal adherence to HIV treatment
No full textObjectives: We sought to examine the association between dispensation of methadone maintenance therapy (MMT) and antiretroviral therapy (ART) at the same facility, across multiple low-barrier dispensing outlets, and achieving optimal adherence to ART among people who use illicit drugs (PWUD). Methods: We used data from the AIDS Care Cohort to Evaluate Exposure to Survival Services (ACCESS) study, a long-running study of a community-recruited cohort of HIV-positive PWUD, linked to comprehensive HIV clinical records in Vancouver, Canada, a setting of no-cost, universal access to HIV care. The longitudinal relationship between MMT-ART dispensation at the same facility and the odds of ≥ 95% ART adherence was analysed using multivariable generalized linear mixed-effects modelling. We conducted a further analysis using a marginal structural mode with inverse probability of treatment weights as a sensitivity analysis. Results: This study included data on 1690 interviews of 345 ART- and MMT-exposed participants carried out between June 2012 and December 2017. In the final multivariable model, MMT-ART dispensation, compared with nondispensation at the same facility, was associated with greater odds of achieving ≥ 95% adherence [adjusted odds ratio (AOR) 1.56; 95% confidence interval (CI) 1.26–1.96]. A marginal structural model estimated a 1.48 (95% CI 1.15–1.80) greater odds of ≥ 95% adherence among participants who reported MMT-ART dispensation at the same facility compared with those who did not. Conclusions: The odds of achieving optimal adherence to ART were 56% higher during periods in which MMT and ART medications were dispensed at the same facility, in a low-barrier setting. Our findings highlight the need to consider a simpler integrated approach with medication dispensation at the same facility in low-threshold settings. © 2019 British HIV Associatio
Microencapsulation of Citrus Grandis peel oil using interfacial precipitation chemistry technique for repellent application
No full textEssential oil of Citrus family plant is known to have repellent effect against mosquito. Unfortunately, due to its high volatility effect, its repellency effect was compromised. The incorporation of essential oil in a microencapsulation formulation has been shown to help improve the stability and potency of the repellent. In this study, Citrus grandis peel oil (CGPO) was encapsulated by using the interfacial precipitation chemistry technique. The microencapsulated CGPO was then formulated into lotion form to produce topical repellent formulation. This study includes the characterization of microcapsules with regards to the morphology, size distribution, zeta potential, Fourier Transmission Infrared spectrophotometer (FTIR), and Thermogravity analysis (TGA). The effectiveness of the microencapsulated CGPO-lotion formulation against mosquitoes was evaluated in the laboratory setting. Results indicated that CGPO have been successfully encapsulated with 6.5 µm in diameter and zeta potential values,-47.9 mV. The FTIR analysis spectrum indicated the presence of interaction between the wall materials in microcapsules. The TGA analysis demonstrated that microencapsulation improved the thermal stability of CGPO. Repellency assay revealed that microencapsulated CGPO-based formulation possessed excellent effect compared with pure CGPO. In conclusion, CGPO was successfully encapsulated and the microencapsulation aid to improve the repellency effect of CGPO against mosquito bites. © 2019, Iranian Journal of Pharmaceutical Research. All rights reserved
Facile synthesis of silver nanoparticles using Averrhoa bilimbi L and Plum extracts and investigation on the synergistic bioactivity using in vitro models
No full textThe bacterial communities (Gram-negative and Gram-positive) form the biofilms which oppose the mode of action of antibiotics and affecting the immune system of the human. These chronic infections related to biofilm are always hard to be cured because of their inherent resistance to both antimicrobial agents and host defense. The present study is devoted to the synthesis of silver nanoparticles (AgNPs) using aqueous extracts of Averrhoa bilimbi leaf and Plum fruit (Prunus bokharensis) and its inhibitory effect on Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi. Here, AgNPs) were successfully prepared by green synthesis method obtained by the reduction of silver nitrate into silver ions. The synthesized AgNPs were characterized by UV-Vis Spectroscopy, XRD, FTIR, FESEM-EDAX and DLS analysis. The antimicrobial effects of the two extract were evaluated by the disk diffusion method. The green synthesized AgNPs exhibited good antibacterial activity against both Gram-negative and Gram-positive. They were also analyzed for their significant antibacterial activities against all the test cultures exposed whereas Escherichia coli and Salmonella typhi topped among other test cultures. The anti-proliferative activity of phytochemical mediated synthesis of Ag NPs was investigated for their cytotoxicity in Vero and Human epidermoid larynx carcinoma cell lines (HEp-2) based on their viability using MTT assay. The present study also represents the synergistic bioactivity of silver nanoparticles using in vitro models. © 2019 Sagadevan et al., published by De Gruyter
Effects of ColdArc welding parameters on the tensile strengths of high strength steel plate investigated using the Taguchi approach
No full textThe objective of this study is to investigate the effect of process parameters on ColdArc welding of high strength steel plate using 1.2 mm diameter mild steel welding wire. A Taguchi Design of Experiments (DOE) method with grey relational analysis approach was selected for data collection and optimization. 9 experiments were conducted following the L9 (33) Taguchi Orthogonal Array Design. The best result from the experiments for tensile strength was obtained for welding parameters of 70 A (current), 17.6 V (voltage) and 800 mm/min welding speed. Based on the results, the Taguchi analysis predicted the optimised tensile strength would be obtained when the welding current, welding voltage and speed are at 70V, 17.6A and 600 mm/min, respectively. Thus, most significant parameters for tensile properties of cold rolled steel is welding speed (37%), voltage (34 %) and current (28%). These factors are critical in determining the tensile strength, where increasing the welding speed reduces the heat input. However, decreasing the heat input by lowering the welding voltage resulted in bad weld bead formation. © Universiti Malaysia Pahang, Malaysi
Relationships between the Older Adult’s Cognitive Decline and Quality of Life: The Mediating Role of the Assistive Mobile Health Applications
No full textThis article examines the link between the older adult's cognitive decline, and Assistive Mobile Health Applications in terms of quality of life as researcher has found scarcity in explaining the mediating role of assistive mobile health applications towards the quality of life of older adults with cognitive decline. Researchers have identified the importance of using assistive mobile health applications in connection of the older adult's cognitive decline. However, it remained unaddressed in the explaining the mediating role of assistive mobile health application. Therefore, this paper aims to provide an insight that the adoption of assistive m-health applications will provide this population with potential solution to their challenging aging life, hence, enhancing their quality of life. In addition, this paper is only a conceptual explanation, as it aims to identify the possible reasons that influence their Smartphone adoption. Factors were identified using a systematic literature review on relevant peer reviewed papers. The study summarized the empirical evidences which were used to support the conceptual explanation. It is expected that this work will lead towards the empirical findings on the explanation of the mediating role of the assistive mobile health applications to address the relationship of older adult's cognitive decline and quality of life. This paper provides directions for future studies in improving the quality of life of older adults. © 2019 International Association of Online Engineering
Fungi in the normal human external ear
No full textAim: The aim of this study is to determine the presence of fungi in the human external ear. Materials and Methods: A total of 84 specimens of skin scraping were taken from the external ear canals of 46 randomly selected adult ears with their consent. Patients were 15 males and 31 females, with a mean age of 51 years (22 years to 86 years). Of these, 38 patients were from both the ears, and 4 each from right or left ear, respectively, making it a total of 84. These samples were sent to the microbiology laboratory for potassium hydroxide staining for fungal elements and then cultured in sabouraud dextrose agar with olive oil. If fungus was detected on the agar after 2-4 weeks of incubation, the type of fungus was read and verified by a microbiologist. Results: Forty specimens were positive (47.6%) and 44 were negative for fungal culture. The positive culture was Malassezia furfur in 31 (77.5%) and other fungi (Candida albicans 1, Candida parapsilosis 6 and Aspergillus species 2) in 9 (22.5%). Conclusion: There are fungi as commensals in the external human ear, M. Furfur is the most common fungus. © 2019 Indian Journal of Otology Published by Wolters Kluwer - Medknow
Corruption and Good Governance: An Analysis of ASEAN's E-Governance Experience
No full textSince its formation in 1967, the Association of Southeast Asian Nations (ASEAN) has progressed to become an economic powerhouse. From a loosely formed grouping in the 1960s, its members have since undergone massive integration. A key motive of the Association is to transfer government and public services onto a technology platform, termed e-government. An important concern is whether e-governance can reduce corruption and stimulate sustainable development. Using traditional governance measures and e-governance indices, this paper analyses the state of governance and corruption in ASEAN. While the deepening of e-governance - via government and public participation - has raised the potential for improving good governance practices, that in itself can be counterproductive as socioeconomic agents could broaden corrupt practices by appropriating its public-good-like characteristics. Hence, ASEAN governments have to implement changes in their communications strategies and feedback mechanisms, remove barriers blocking the spread and use of information technology, and promote a collaborative environment with civil society organizations, while considering the use of the "carrot and stick" approach to improve good governance. © 2019 ISEAS - Yusof Ishak Institute
Insecticide susceptibility status and resistance mechanism of Anopheles cracens Sallum and Peyton and Anopheles maculatus Theobald (Family: Culicidae) from knowlesi malaria endemic areas in Peninsular Malaysia
No full textObjective: To assess the insecticide susceptibility status of Anopheles cracens (An. cracens) and Anopheles maculatus (An. maculatus) from knowlesi malaria endemic areas in Peninsular Malaysia towards DDT, malathion and deltamethrin and to determine the resistance mechanism involved. Methods: Adult and larval mosquitos were collected for surveillance. Susceptibility status of Anopheles was determined using the standard WHO adult bioassay, larval bioassay and biochemical enzyme assay. Results: WHO adult bioassay results indicated An. cracens collected from Kampung Sungai Ular, Pahang was resistant towards 4% DDT, while An. maculatus collected from Kampung Sokor, Kelantan and Kampung Sungai Lui, Selangor exhibited resistance towards 4% DDT. However, the enzyme activity profiles varied according to strains and species. The resistance ratio of larval bioassay, showed that all strains and species tested were susceptible to malathion and temephos. Conclusions: Since only a few anopheline strains exhibited low level of insecticide resistance towards malathion, DDT and temephos. These insecticides are still considered effective for vector control program towards An. cracens and An. maculatus. © 2019 Asian Pacific Journal of Tropical Medicine Produced by Wolters Kluwer-Medknow