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Determinants of Infant Mortality in Older ASEAN Economies
No full textInfant mortality in the Association of Southeast Asian Nations (ASEAN) has been declining, yet disparities remain between the nations. This paper therefore explores the determinants of infant mortality in the older ASEAN-4 economies, Malaysia, Thailand, Indonesia and the Philippines using an Autoregressive Distributed Lag (ARDL) Error Correction Model framework. The key findings of the study are: First, there is evidence of long-run relationships among infant mortality, education, female fertility, income and access to healthcare. Second, the determinants of infant mortality vary between countries. Female fertility emerged as the main determinant of infant mortality in Malaysia, while access to healthcare matter for infant mortality in Indonesia, and to a lesser extent for the Philippines. The income effect is significant for reducing infant mortality in Malaysia, while female education is important for Indonesia and Thailand. Third, the speed of adjustment of infant mortality rate is comparatively low in ASEAN-4
Innovative cross-axis-wind-turbine design
Get PDFResearchers and inventors have suggested novel wind turbine designs that were claimed to enhance the energy output of the existing vertical axis wind turbines (VAWT). There are many advantages of VAWTs compared with HAWTs. Research has shown that VAWTs are more suitable for turbulent wind flow and urban applications. However, the efficiency and low self-start ability of VAWTs are always the main drawbacks
especially for the lift-type VAWTs. Unlike HAWTs, the rotor blades for VAWTs do not always provide positive torque during operation. Various designs have been suggested to increase the performance of VAWTs which includes different blade sections and VAWT configurations. Power augmentation features have been proven as one of the wind turbine performance enhancement methods particularly for vertical axis wind turbines (VAWTs). The augmentation devices can consist of a duct, stator, diffuser, guide vanes, and other devices. Researches showed that with the aid of an augmentation device, the power output of a VAWT can be increased remarkably. The deflected wind flows improve the performance significantly as well as reduce the self-start velocity of the turbine. Furthermore, a new type of wind turbine namely the cross-axis-wind-turbine (CAWT) that is capable to harness wind power from both the horizontal and vertical components of the oncoming wind is presented. The
CAWT comprises of 6 horizontal blades and 3 vertical blades arranged in a cross axis orientation. In the initial
testing, the wind deflectors were used to guide the oncoming wind towards the upward directions. The result showed that the CAWT have increased power output as well as rotational speed when compared with a conventional straight-bladed VAWT especially when integrated with a 45° deflector which produced a power coefficient about 2.8 times higher than the VAWT. The rotor rotational speed was increased by 70% with a better starting behaviour. The CAWT is a practical wind turbine which has various applications such as in standalone systems, urban and offshore wind farms
Conceptual design of a novel power-augmented marine current turbine
Get PDFOcean or marine field become one of the main concerns of renewable source in the world with the emergence of marine technology. Since water density is 800 times denser than the density of air and the power of the flow is proportional to the cube of the fluid velocity, therefore same amount of energy generated in wind turbine can be produced by water even with lower flow velocity. Many researchers started to design and fabricate the marine current turbine in order to convert tidal stream into electricity. Tidal energy offers us a promising future. Nearly half or more than 50% of marine current turbines are designed in horizontal axis and ducted. For example, Marine Current Turbine Ltd (UK) had come out of many turbines such as SeaGen U, SeaGen F and so
on, all of them are horizontal axis, huge and weighty. Though vertical-axis turbines are generally less efficient
than horizontal-axis turbines, they do have some distinct advantages: vertical-axis turbines can have a rectangular
cross section, which allows them to be more efficiently packed in arrays than section horizontal-axis turbines.
Another benefit is the ability to generate power from any flow direction that is perpendicular to the axis, which is
extremely advantageous in a tidal flow. Besides, there are some marine turbines that were enclosed by the diffuser
or duct, such as Rotech tidal turbine (RTT), which functioned to channel the flow in order to increase water flow velocity. Shape of the diffuser and the additional support structure to the diffuser are the challenges faced during fabrication and installation. In this paper, a conceptual design of a novel power-augmented marine current turbine which utilizes the concept of cross-axis wind turbine and augmented guide vane is proposed. The conceptual
marine current turbine system is designed by intercepting the two guide vanes in between three individual turbines
and also two diffusers at the outer part of the system. The conceptual design of this cross-axis turbine with helical
blade is similar to the Gorlov helical turbine but there are some differences in the radial blades which are designed
as 8 degrees upper and lower respectively to the horizontal axis of the connector hub. The two layers radial bladerotors
are offset by 60 degrees. The NACA 0015 airfoil profile is used as turbine blade in this design. The augmented guide vane could channel the water stream and increase the flow velocity when strikes to the turbine blade. Turbine is designed based on the concept of cross-axis wind turbine (CAWT) which gives the advantages of better self-starting at low velocity and the greater torque at high velocity. A 3D model was constructed and simulated by using the computational fluid dynamics software, ANSYS-Fluent. In the simulation, the velocity of water flow and the rotational speed of turbine were increased with the integration of the guide-vane and diffuser features. It is estimated that this conceptual design turbine will achieve 60% increase in energy gain
Angiostrongylus mackerrasae and A. cantonensis (Nematoda: Metastrongyloidea) belong to same genetic lineage: evidence from mitochondrial protein-coding genes
No full textAngiostrongylus mackerrasae is a parasitic nematode of rats found in Australia. When first reported, it was referred to as A. cantonensis. Recent molecular studies, including the mitochondrial genome, indicate that it is highly similar to A. cantonensis. These studies did not include A. malaysiensis, another member of the A. cantonensis species complex, for comparison. The present study examined the genetic distance and phylogenetic relationship between the component taxa (A. cantonensis, A. mackerrasae and A. malaysiensis) of the A. cantonensis species complex, based on the 12 protein-coding genes (PCGs) of their mitochondrial genome. Both the nucleotide and amino acid sequences were analysed. Angiostrongylus mackerrasae and A. cantonensis are members of the same genetic lineage and both are genetically distinct from A. malaysiensis. The genetic distance based on concatenated nucleotide sequences of 12 mt-PCGs between A. mackerrasae and A. cantonensis from Thailand is p = 1.73%, while that between the Thai and Chinese taxa of A. cantonensis is p = 3.52%; the genetic distance between A. mackerrasae and A. cantonensis from China is p = 3.70%. The results indicate that A. mackerrasae and A. cantonensis belong to the same genetic lineage, and that A. mackerrasae may be conspecific with A. cantonensis. It remains to be resolved whether A. mackerrasae is conspecific with A. cantonensis or undergoing incipient speciation
Optimization of Mechanical Properties for Polyoxymethylene/Glass Fiber/Polytetrafluoroethylene Composites Using Response Surface Methodology
No full textThis paper investigated the effects of polytetrafluoroethylene (PTFE) micro-particles on mechanical properties of polyoxymethylene (POM) composites. Since PTFE is immiscible with most polymers, the surface was etched using sodium naphthalene salt in tetrahydrofuran to increase its surface energy. The effects of two variables, namely PTFE content and PTFE etch time, on the mechanical properties of the composite were studied. Experiments were designed in accordance to response surface methodology (RSM) using central composite design (CCD). Samples were prepared with different compositions of PTFE (1.7, 4.0, 9.5, 15.0, or 17.3 wt %) at different PTFE etch times (2.9, 5.0, 10.0, 15.0, or 17.1 min). Four mechanical properties of the POM/GF/PTFE composites, that is, strength, stiffness, toughness, and hardness, were characterized as a function of two studied variables. The dependency of these mechanical properties on the PTFE etch conditions was analyzed using analysis of variance (ANOVA). Overall desirability, D global index, was computed based on the combination of these mechanical properties for POM/GF/PTFE composites. The D global index was found to be 87.5%, when PTFE content and PTFE etch time were 6.5% and 10 min, respectively. Good correlation between experimental and RSM models was obtained using normal probability plots
Development and Validation of the Return and Disposal of Unused Medications Questionnaire (ReDiUM) in Malaysia
No full textThe aim of our study was to develop and validate the return and disposal of unused medications (ReDiUM), as there are currently no validated tools available (worldwide) to assess this. The ReDiUM was developed by an expert panel. It was then administered to community-dwelling adults, who could understand English, at baseline and 2 weeks later. A total of 338/354 participants agreed to participate (response rate = 95.4%). Flesch reading ease was 60. The overall Cronbach’s α was 0.703 (range = 0.609-0.762). At test-retest, κ values ranged from 0.244 to 0.523. Median total knowledge score was 60% (interquartile range = 40% to 70%). The majority of participants (94.4%) knew that improper drug disposal has harmful effects on the environment. However, their knowledge was low (11.2%) regarding the disposal of pressurized metered-dose inhalers in the garbage. The ReDiUM was found to be a valid and reliable instrument to assess the knowledge, attitude, and practice on the ReDiUM in Malaysia
Selection of reference genes for transcript profiling of Sargassum polycystum by quantitative real-time polymerase chain reaction
No full textSargassum species are one of the major alginate-producing seaweed species in Asian countries. Alginate is widely used in food, feed, pharmaceutical and medical industries as thickening and stabilizing agents. To establish a set of consistently expressed genes as reference genes for quantitative real-time polymerase chain reaction (qRT-PCR) studies of Sargassum polycystum (Fucales, Ochrophyta) in samples collected at two distinct time points from the field, four candidate reference genes, namely ribosomal protein L3 (RPL3), ribosomal protein S15 (RPS15), alpha-tubulin (α-TUB) and eukaryotic translation elongation factor 1 alpha (TEF1α), were analyzed using geNorm and NormFinder. The results showed that RPL3, α-TUB and TEF1α were the most stable genes using both programs, whereas RPS15 gene was shown to be the least stable. Identification of stably expressed reference genes is crucial for qRT-PCR studies to allow accurate quantification of target gene expression levels. In addition, the expression of key enzyme in the final step of alginate biosynthesis pathway mannuronan C5 epimerase-SP01411 (MC5E-SP01411) and mannuronan C5 epimerase-SP02271 (MC5E-SP02271) were differentially expressed in the seaweeds collected at two distinct time points from the field. To our knowledge, this is the first report on validation of reference genes for any Sargassum species. Our data provide a basis for the selection of reference genes for future biological research in related studies
Performance of combined PTFE hydrophilic and hydrophobic membrane during laundry/detergent wastewater treatment by air gap membrane distillation (AGMD): an experimental study
No full textMembrane distillation (MD) is making a rapid progress in desalination and wastewater treatment research. Though MD produces lower distillate yield compared with other membrane processes, its ability to be used with varieties of renewable and waste energy source coupled to produce ultrapure water makes it a competitive choice. One of the major drawbacks of MD is the fouling and pore wetting of the membrane surface, and therefore modifications to membrane surface characteristics and combining MD with other techniques are necessary for successful rejection of all sorts of organic, inorganic and biological contaminants, except few. One of them is household wastewater containing common laundry detergent sodium dodecylbenzenesulfonate. Although it has been reported that alkaline surfactant causes pore wetting in hydrophobic membranes, but the extent of damage and the severe drop in permeate quality has not been reported. In this work, the preliminary experiments have been carried out with standard laundry wastewater and it has been observed that commercially available hydrophobic polytetrafluroethylene membrane permits all the constituents of the feed water in presence of small amount of laundry detergent. Complete pore wetting of the membrane makes it reach very high permeate flux (40 L/m2 h) and the distillate quality is near to the feed water (>2,400 µS/cm). A simple technique was developed to prevent pore wetting, by combining hydrophilic and hydrophobic membrane without using any interfacial-bonding agent or crosslinking agent. This simple technique successfully produced pure distillate from feed water containing detergent with a conductivity of 12–20 µS/cm
Effect of the addition of phytomix-3+ mangosteen on antioxidant activity, viability of lactic acid bacteria, type 2 diabetes key-enzymes, and sensory evaluation of yogurt
No full textPhytomix-3 was prepared from the mixture of Lycium barbarum, Momordica grosvenori and Psidium guajava leaves and added together with Garcinia mangostana (pulp and pericarp). The effect of phytomix-3+ mangosteen (Ph-3+M) enriched yogurt was studied for peptide content, inhibitory activities on α-amylase, α-glucosidase, the viability of S. thermophilus and Lactobacillus spp. during 0, 7 and 14 days of storage, both before (pre-) and after (post-) simulated gastrointestinal digestion. Antioxidant activity (DPPH assay), total phenolic content and sensory evaluation were also investigated during the storage period. Ph-3+M yogurt showed significantly higher (p < 0.05) antioxidant activity and TPC compared to plain yogurt during storage. The highest peptide concentrations of pre- and post-digested Ph-3+M yogurt was shown on day 7 of storage. Ph-3+M yogurt displayed strong inhibition on α-glucosidase and mild inhibition on α-amylase inhibitory activities. Ph-3+M yogurt enhanced the viability of S. thermophilus and Lactobacillus spp. In conclusion, Ph-3+M yogurt could provide beneficial effects as a functional food
“Allah will decide my life and death”: Religion and spirituality among populations at risk for HIV in Malaysia
No full textWe examined the influence of religion and spirituality on HIV risk contexts through in-depth interviews with men who have sex with men (n = 10) and female commercial sex workers (n = 10) in Malaysia. Using a grounded theory approach, five themes emerged from the interviews: (a) religion encourages caring for health, (b) health is influenced by a higher power, (c) prayer is a conduit to health assistance, (d) stigma is compounded by religion but it does not limit one’s spirituality, and (e) religion is not but should be incorporated into HIV campaigns. Incorporation of spirituality in service provision and addressing stigma is warranted