19672 research outputs found
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Influence of Graphene Nanosheets on Rheology, Microstructure, Strength Development and Self-Sensing Properties of Cement Based Composites
No full textIn this research, Graphene oxide (GO), prepared by modified hammer method, is characterized using X-ray Diffraction (XRD), Fourier Transform Infrared (FT-IR) Spectrometry and Raman spectra. The dispersion efficiency of GO in aqueous solution is examined by Ultraviolet-visible spectroscopy and it is found that GO sheets are well dispersed. Thereafter, rheological properties, flow diameter, hardened density, compressive strength and electrical properties of GO based cement composite are investigated by incorporating 0.03% GO in cement matrix. The reasons for improvement in strength are also discussed. Rheological results confirm that GO influenced the flow behavior and enhanced the viscosity of the cement based system. From XRD and Thermogravimetric Analysis (TGA) results, it is found that more hydration occurred when GO was incorporated in cement based composite. The GO based cement composite improves the compressive strength and density of mortar by 27% and 1.43%, respectively. Electrical properties results showed that GO-cement based composite possesses self-sensing characteristics. Hence, GO is a potential nano-reinforcement candidate and can be used as self-sensing sustainable construction material
Tamarindus indica seeds improve carbohydrate and lipid metabolism: An in vivo study
No full textBackground: The tamarind seeds have a lot of nutrients that may be used to control cholesterol or glucose levels. Objective(s): The effects of tamarind seeds (T) on lipid and carbohydrate metabolism in rats were studied. Rats were offered basal diet (BD) with T (2%, 4% or 8%) or without T. Materials and methods: Feeding and growth performance in rats were measured and samples of liver and blood were analyzed for glycogen content and levels of cholesterol and glucose respectively. Results: The inclusion of T in the diet influences the feeding and growth performance in rats. The serum cholesterol level was reduced (p < 0.05) in Sprague Dawley (SD) rats fed on basal diet (BD) containing 4% and 8% T (0.24 ± 0.14 g/l and 0.31 ± 0.06 g/l respectively) compared to control (0.79 ± 0.04 g/l). The serum glucose levels in the spontaneous hypertensive rats (SHR) was lower (50.74 ± 2.50 mg/dl; p < 0.05) than control (93.52 ± 10.83 mg/dl) at 4% T. Incorporation of increasing doses of T resulted in linear increase of glycogen storage in livers of SD rats fed on BD and high sucrose diet. Conclusion: Tamarind seeds can lower blood glucose and serum cholesterol and enhance storage of glycogen in rats
Decision making process and factors contributing to research participation among general practitioners: A grounded theory study
No full textIntroduction The participation of general practitioners (GPs) in primary care research is variable and often poor. We aimed to develop a substantive and empirical theoretical framework to explain GPs’ decision-making process to participate in research. Methods We used the grounded theory approach to construct a substantive theory to explain the decision-making process of GPs to participate in research activities. Five in-depth interviews and four focus group discussions were conducted among 21 GPs. Purposeful sampling followed by theoretical sampling were used to attempt saturation of the core category. Data were collected using semi-structured open-ended questions. Interviews were recorded, transcribed verbatim and checked prior to analysis. Open line-by-line coding followed by focus coding were used to arrive at a substantive theory. Memoing was used to help bring concepts to higher abstract levels. Results The GPs’ decision to participate in research was attributed to their inner drive and appreciation for primary care research and their confidence in managing their social and research environments. The drive and appreciation for research motivated the GPs to undergo research training to enhance their research knowledge, skills and confidence. However, the critical step in the GPs’ decision to participate in research was their ability to align their research agenda with priorities in their social environment, which included personal life goals, clinical practice and organisational culture. Perceived support for research, such as funding and technical expertise, facilitated the GPs’ participation in research. In addition, prior experiences participating in research also influenced the GPs’ confidence in taking part in future research. Conclusions The key to GPs deciding to participate in research is whether the research agenda aligns with the priorities in their social environment. Therefore, research training is important, but should be included in further measures and should comply with GPs’ social environments and research support
Development of standard clinical endpoints for use in dengue interventional trials
No full textDengue is a major public health problem worldwide. Although several drug candidates have been evaluated in randomized controlled trials, none has been effective and at present, early recognition of severe dengue and timely supportive care are used to reduce mortality. While the first dengue vaccine was recently licensed, and several other candidates are in late stage clinical trials, future decisions regarding widespread deployment of vaccines and/or therapeutics will require evidence of product safety, efficacy and effectiveness. Standard, quantifiable clinical endpoints are needed to ensure reproducibility and comparability of research findings. To address this need, we established a working group of dengue researchers and public health specialists to develop standardized endpoints and work towards consensus opinion on those endpoints. After discussion at two working group meetings and presentations at international conferences, a Delphi methodology-based query was used to finalize and operationalize the clinical endpoints. Participants were asked to select the best endpoints from proposed definitions or offer revised/new definitions, and to indicate whether contributing items should be designated as optional or required. After the third round of inquiry, 70% or greater agreement was reached on moderate and severe plasma leakage, moderate and severe bleeding, acute hepatitis and acute liver failure, and moderate and severe neurologic disease. There was less agreement regarding moderate and severe thrombocytopenia and moderate and severe myocarditis. Notably, 68% of participants agreed that a 50,000 to 20,000 mm3 platelet range be used to define moderate thrombocytopenia; however, they remained divided on whether a rapid decreasing trend or one platelet count should be case defining. While at least 70% agreement was reached on most endpoints, the process identified areas for further evaluation and standardization within the context of ongoing clinical studies. These endpoints can be used to harmonize data collection and improve comparability between dengue clinical trials
A Simple Aluminum Bromide-Promoted Diastereoselective Synthesis of Panduratin A Derivatives
No full textA facile diastereoselective synthesis of panduratin A derivatives using commercially available aluminum(III) bromide is reported. The effect of substituents on the Diels-Alder reaction of various trans -chalcones with (E)-ocimene was investigated. A series of panduratin A derivatives were prepared in moderate to good yields
Draft genome sequence of Vitellibacter aquimaris D-24 T isolated from seawater
No full textVitellibacter aquimaris D-24T (=KCTC 42708T = DSM 101732T), a halophilic marine bacterium, was isolated from seawater collected from Desaru beach, Malaysia. Here, we present the draft genome sequence of D-24T with a genome size of approximately 3.1 Mbp and G + C content of 39.93%. The genome of D-24T contains genes involved in reducing a potent greenhouse gas (N2O) in the environment and the degradation of proteinaceous compounds. Genome availability will provide insights into potential biotechnological and environmental applications of this bacterium
Antioxidant Properties and Yield of Wood Ear Mushroom, Auricularia polytricha (Agaricomycetes), Cultivated on Rubberwood Sawdust
No full textMushroom cultivation has become an important component of agriculture, providing food and contributing to the global economy. It uses vertical space and addresses issues of food quality, health improvement, and environmental sustainability. Auricularia mushrooms are popular ingredients in traditional Chinese cuisine. The objective of this study was to determine yield and evaluate radical scavenging capacity of A. polytricha cultivated on rubberwood sawdust on a large scale; we measured total phenolic content; DPPH, hydroxyl, superoxide anion, and peroxyl radical scavenging; and reducing power. Cultivation on rubberwood sawdust produces an average of 4 harvests per bag and a biological efficiency of 80-82%. The antioxidant capacity investigations revealed that the ethyl acetate fraction was the most potent radical scavenger in all assays except that for superoxide anions, whereas the aqueous fraction exhibited mild to moderate antioxidant capacity in scavenging the various radicals. Artificial cultivation of A. polytricha on rubberwood sawdust yields many sporophores with potent antioxidant capacity
The privatization of public streets and urban spaces in Malaysia
No full textIn the last two decades, Malaysia has embedded good neighborhood principles in its planning plans that promote diversity and accessibility in urban residential areas. However, the emerging trends of the privatization of public streets and open spaces in urban residential areas in Malaysia offer the opportunity to study complex urban governance processes in a democratic and developing country. Using empirical evidence, this article recounts the fascinating saga of how various actors - urban planners, resident associations, residents of open neighborhoods and residents of guarded neighborhoods - responded to the privatization of public streets and open spaces in Malaysia. While planners described Greater Klang Valley as a diverse city in Malaysia, they sometimes tolerated the privatization of public streets and open spaces through neoliberal policies
Comparative proteomics reveals that YK51, a 4-Hydroxypandurantin-A analogue, downregulates the expression of proteins associated with dengue virus infection
No full textDengue is endemic throughout tropical and subtropical regions of the world. Currently, there is no clinically approved therapeutic drug available for this acute viral infection. Although the first dengue vaccine Dengvaxia has been approved for use in certain countries, it is limited to those without a previous dengue infection while the safety and efficacy of the vaccine in those elderly and younger children still need to be identified. Therefore, it is becoming increasingly important to develop therapeutics/drugs to combat dengue virus (DENV) infection. YK51 is a synthetic analogue of 4-Hydroxypandurantin A (a compound found in the crude extract of the rhizomes of Boesenbergia rotunda) that has been extensively studied by our research group. It has been shown to possess outstanding antiviral activity due to its inhibitory activity against NS2B/NS3 DENV2 protease. However, it is not known how YK51 affects the proteome of DENV infected cells. Therefore, we performed a comparative proteomics analysis to identify changes in protein expression in DENV infected HepG2 cells treated with YK51. Classical two-dimensional gel electrophoresis followed by protein identification using tandem mass spectrometry was employed in this study. Thirty proteins were found to be down-regulated with YK51 treatment. In silico analysis predicted that the down-regulation of eight of these proteins may inhibit viral infection. Our results suggested that apart from inhibiting the NS2B/NS3 DENV2 protease, YK51 may also be causing the down-regulation of a number of proteins that may be responsible in, and/or essential to virus infection. However, functional characterization of these proteins will be necessary before we can conclusively determine their roles in DENV infection
Seismic Vulnerability of Low- and Mid-Rise Reinforced Concrete Buildings in Malaysia Designed by Considering Only Gravity Loads
No full textThis study focuses on seismic vulnerability assessment of reinforced concrete buildings designed by considering only gravity loads. Fragility curves are developed for a three-story reinforced concrete office frame building and a four-story reinforced concrete school building with unreinforced masonry infill walls representative of the essential facilities in Malaysian Peninsula. A simplified modeling approach is adopted for fragility analysis, which can effectively reduce the computational effort. A set of fragility curves are developed in terms of peak ground acceleration with lognormal cumulative distribution functions. The fragility analysis shows that the seismic performance of the structures met the desirable performance level recommended by current seismic code, demonstrating low vulnerability of the structures within Malaysian Peninsula. It is also shown that the soil condition should be taken into consideration for effective seismic vulnerability assessment. Finally, the fragility curves developed in this study are compared to those of HAZUS