Heat transfer augmentation of mixture ratio TiO2 to SiO2 in hybrid nanofluid / K.A. Hamid...[et al.]

The efficiency in heat transfer fluid for cooling systems can be improved with the use of hybrid nanofluid. The combination of two or more single nanoparticles in the hybrid nanofluid improve their thermo-physical properties, hence contribute in heat transfer performance. The experimental investigation on forced convection heat transfer of hybrid nanofluid have been carried out on the evaluation of heat transfer coefficient and Nusselt number. The designated working temperature was 30oC, tested for various volume percentage of TiO2 to SiO2. The experiment was conducted in a plain tube under constant heat flux at 7,955W/m2. The hybrid nanofluid was prepared at 1.0% volume concentration at three mixture ratios of TiO2 to SiO2. The range of average enhancement in the heat transfer coefficient and Nusselt number observed were 13.6-29.7% and 9.0-17.8%, respectively. The ratio of TiO2 to SiO2 at 20:80 showed the optimum ratio that can be used to obtain maximum enhancement in heat transfer coefficient and Nusselt number. The pressure drop of the hybrid nanofluid increased about double the base fluid for ratio 50:50. Due to the small increment in friction factor which was 1.03 times, the hybrid nanofluid are appropriate for application of cooling systems. It is recommended to use TiO2- SiO2 nanofluid at ratio 20:80 due to its significant enhancement in heat transfer but least increment in friction factor

Determinants of snakebite mortality in Asia: A systematic review

Purpose: This systemic review summarizes the evidence exploring the determinants of mortality due to snakebite envenomation in Asia. Materials and methods: The database PubMed, Web of Science and Science Direct were searched to identify the relevant literatures concerning mortality due to snakebites mortality in Asia. All the articles chosen were critically appraised for its quality using a mixed-method assessment tool by two independent reviewers with discrepancies sorted by a third person. Results: A total of 7 studies were included in the final analysis which was 3 cross-sectional studies, 2 case reports, 1 observation prospective study and 1 randomized control trial study. Two studies were conducted in India and two studies in Sri Lanka while one study was conducted in Taiwan, Vietnam and Nepal respectively. The cases of snakebite victims were retrieved from the year of 1987 until 2017. In total, there were 762 cases of snakebite victims recorded, with 61 of those victims succumbed to death. From the final total of 7 studies, 4 of the studies showed snakebites mortality were related to delayed treatment access and 3 studies due to suboptimal care. Conclusion: Mortality and morbidity can be reduced if there is a quick access for victims to emergency medical care, rapid transfer time to hospital and receiving immediate optimal medical treatment from trained medical staff once in the hospital or dispensary. © 202

Designing a broad-spectrum integrative approach for cancer prevention and treatment

Targeted therapies and the consequent adoption of "personalized" oncology have achieved notablesuccesses in some cancers; however, significant problems remain with this approach. Many targetedtherapies are highly toxic, costs are extremely high, and most patients experience relapse after a fewdisease-free months. Relapses arise from genetic heterogeneity in tumors, which harbor therapy-resistantimmortalized cells that have adopted alternate and compensatory pathways (i.e., pathways that are notreliant upon the same mechanisms as those which have been targeted). To address these limitations, aninternational task force of 180 scientists was assembled to explore the concept of a low-toxicity "broad-spectrum" therapeutic approach that could simultaneously target many key pathways and mechanisms. Using cancer hallmark phenotypes and the tumor microenvironment to account for the various aspectsof relevant cancer biology, interdisciplinary teams reviewed each hallmark area and nominated a widerange of high-priority targets (74 in total) that could be modified to improve patient outcomes. For thesetargets, corresponding low-toxicity therapeutic approaches were then suggested, many of which werephytochemicals. Proposed actions on each target and all of the approaches were further reviewed forknown effects on other hallmark areas and the tumor microenvironment. Potential contrary or procar-cinogenic effects were found for 3.9% of the relationships between targets and hallmarks, and mixedevidence of complementary and contrary relationships was found for 7.1%. Approximately 67% of therelationships revealed potentially complementary effects, and the remainder had no known relationship. Among the approaches, 1.1% had contrary, 2.8% had mixed and 62.1% had complementary relationships. These results suggest that a broad-spectrum approach should be feasible from a safety standpoint. Thisnovel approach has potential to be relatively inexpensive, it should help us address stages and types ofcancer that lack conventional treatment, and it may reduce relapse risks. A proposed agenda for futureresearch is offered

Experimental investigation of nanoparticle mixture ratios on TiO2–SiO2 nanofluids heat transfer performance under turbulent flow

The new class of fluids namely nanofluids are highly desirable in the enhancement of thermal properties. Various studies were carried out based on their greater thermal performance. The nanofluids are also beneficial in improving the heat transfer performance of devices or systems that require cooling operations. However, the performance of nanofluids with dispersion of two or more different nanoparticles is limited in the literature. Hence, the present study was carried out to investigate the heat transfer performance of TiO2–SiO2 nanofluids for various nanoparticle mixture ratios dispersed in a water/ethylene glycol (W/EG) mixture. The convection heat transfer experiment is conducted under turbulent region with Reynolds number from 3000 to 24,000. Five composite mixtures in volume percent of TiO2 and SiO2 nanoparticles are prepared with mixture ratios (TiO2:SiO2) of 20:80, 40:60, 50:50, 60:40 and 80:20 for a constant volume concentration of 1.0%. The heat transfer performance and friction factor were evaluated for the bulk temperatures of 30, 50 and 70 °C. High performance was seen at a 40:60 mixture ratio with heat transfer enhancement of 35.32% at 70 °C temperature. The mixture ratio of 50:50 showed the least enhancement of 9.02% in heat transfer coefficient for a working temperature of 30 °C. Furthermore, the friction factor of the nanofluids is practically negligible due to the small increment. As a conclusion, the nanoparticle mixture ratios of TiO2–SiO2 nanofluids contributed to the overall performance of heat transfer. It was recommended to use 20:80 and 40:60 mixture ratios of TiO2–SiO2 nanofluids in heat transfer systems

An investigation of border shopping development at Padang Besar

Padang Besar, a border town between the States of Malaysia and Thailand is well known for its shopping activities since early 1950s, with the establishment of shophouses along the border. However, the development and shopping facilities offered to the visitors seem to be insufficient. Hence, the main objective of this paper is to provide some understanding on the development of border shopping scenario at Padang Besar. Grounded theory qualitative data analysis strategy was employed in an attempt to generate the understanding of the border shopping development from the tourism supply chains perspective.The data was gathered through personal interviews and observations.The finding revealed that the town of Padang Besar does has a potential to be developed into a border shopping tourism destination since the town itself is associated mainly with border shopping activities

Prevalence of Serum Celiac Antibodies in a Multiracial Asian Population-A First Study in the Young Asian Adult Population of Malaysia

Background: Celiac disease (CD) is an immune-mediated disorder induced by the ingestion of gluten in genetically susceptible persons. The prevalence of CD in Malaysia is unknown. We aim to determine the seroprevalence of CD antibodies and also investigate the correlation between H. pylori infection and CD in the young and healthy multiracial Malaysian population. Methods: Healthy young adult volunteers between the ages of 18-30 years were consecutively recruited from June 2012 to May 2014 at the University of Malaya Medical Centre (UMMC), Kuala Lumpur. Serum samples from all the participants were tested for anti-gliadin antibody immunoglobulin A/immunoglobulin G (IgA/IgG) and anti-tissue transglutaminase antibody (tTG) IgA/IgG. Samples positive for both anti-gliadin and anti-tTG were further validated for anti-human endomysial IgA antibodies (EmA). Serological diagnosis of CD was made when anti-gliadin, anti-tTG and anti-EmA were positive. Results: 562 qualified participants with mean age 24 ± 2.4 years old were recruited into our study. CD was found in 7 participants where most of them were asymptomatic and unaware of their CD status. The median of anti-gliadin and anti-tTG IgA/IgG value was 38.2 U/ml (interquartile range, 28.3-60.4 U/ml) and 49.2 U/ml (interquartile range, 41.1-65.9 U/ml), respectively. Seroprevalence of CD antibodies was 1.9% (6 out of 324) in female while only 0.4% (1 out of 238) in male. Seroprevalence among Malay was 0.8% (2 of 236), Chinese was 1.7% (3 of 177) and Indian was 1.3% (2 of 149). Overall, seroprevalence of CD antibodies in healthy asymptomatic adults in the Malaysian population was 1.25% (95% CI, 0.78%-1.72%). No significant relationship was discovered between CD and H. pylori infection. Conclusions: The seroprevalence of CD antibodies in healthy young adults in the Malaysian population was 1.25% (1 in 100). CD is underdiagnosed and it could be a much greater problem in Malaysia than previously thought

Compact L-band switchable dual wavelength SOA based on linear cavity fiber laser

A semiconductor optical amplifier (SOA) based linear cavity L-band dual wavelength fiber laser (DWFL) with a switchable output is proposed and its operation demonstrated. The DWFL is configured as a linear cavity, with a 1 × 24 arrayed waveguide grating together with two optical switches providing channel spacing tunability. An L-band SOA, with a central operating wavelength of 1580 nm and an operation bandwidth of 1500–1640 nm serves as the gain medium of the proposed laser cavity. The DWFL is able to generate a dual-wavelength output, with the widest spacing obtained being 18.7 nm and the narrowest spacing being 0.8 nm. The generated output is highly stable, with only minor power fluctuations of less than 2 dB as well as having a signal-to-noise ratio of 42 dB. The proposed setup would have numerous uses, particularly for sensor application