Displaying all 15 publications

Abstract:
Sort:
  1. Diez Roux AV, Slesinski SC, Alazraqui M, Caiaffa WT, Frenz P, Jordán Fuchs R, et al.
    Glob Chall, 2019 Apr;3(4):1800013.
    PMID: 31565372 DOI: 10.1002/gch2.201800013
    This article describes the origins and characteristics of an interdisciplinary multinational collaboration aimed at promoting and disseminating actionable evidence on the drivers of health in cities in Latin America and the Caribbean: The Network for Urban Health in Latin America and the Caribbean and the Wellcome Trust funded SALURBAL (Salud Urbana en América Latina, or Urban Health in Latin America) Project. Both initiatives have the goals of supporting urban policies that promote health and health equity in cities of the region while at the same time generating generalizable knowledge for urban areas across the globe. The processes, challenges, as well as the lessons learned to date in launching and implementing these collaborations, are described. By leveraging the unique features of the Latin American region (one of the most urbanized areas of the world with some of the most innovative urban policies), the aim is to produce generalizable knowledge about the links between urbanization, health, and environments and to identify effective ways to organize, design, and govern cities to improve health, reduce health inequalities, and maximize environmental sustainability in cities all over the world.
  2. Dhar BK, Ayittey FK, Sarkar SM
    Glob Chall, 2020 Sep 28.
    PMID: 33042575 DOI: 10.1002/gch2.202000038
    The purpose of the study is to find out the psychological impact of the COVID-19 pandemic on university students. The study focuses on the university students from different public and private universities of Bangladesh through a set of questionnaires according to the guideline of Generalized Anxiety Disorder Scale (GAD-7). The result among 15 543 respondents shows that 44.59% are suffering from severe anxiety, 48.41% moderate anxiety, and only 3.82% mild anxiety. The results highlight that all epidemic-related stressors are positively correlated with the level of anxiety. Among the epidemic-related stressors, worry about economic influences during and after COVID-19 (r = 0.342, p < 0.001) and worry about the influence of COVID-19 on daily life (r = 0.340, p < 0.001) have a highly positive impact on the level of anxiety. Following these stressors, worry about academic delays due to COVID-19 (r = 0.326, p < 0.001) and worry about the social support during COVID-19 (r = 0.321, p < 0.001) have moderately and positively correlated with the level of anxiety. The study suggests that proper government support, as well as social awareness, should be monitored during epidemics for decreasing anxiety and maintaining a good mental health of the university students.
  3. Islam MN, Liza AA, Khatun ML, Faruk MO, Das AK, Dey M, et al.
    Glob Chall, 2021 Sep;5(9):2100002.
    PMID: 34504715 DOI: 10.1002/gch2.202100002
    This study investigates the efficacy of chemically modified bone adhesive as a formaldehyde-free binder for wood-based industries. Two different types of adhesive are formulated after chemical modification of bone powder using sulfuric acid (0.5 m) and polyvinyl acetate (PVA). Gel time, solid content, Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), viscosity, and single lap joint test for shear strength are analyzed in order to assess the adhesive properties. To analyze the efficacy of the formulated adhesive, particleboards are fabricated using boiled and unboiled sugarcane bagasse. The physical and mechanical properties of the fabricated panels are measured following ASTM standards. It is found that adhesive Type C (T-C) has the shortest gel time of 4.2 min for the highest shear strength, i.e., 5.31 MPa. The particleboard (BTC-2) fabricated using T-C adhesive shows a highest density of 0.73 g cm-3, a modulus of elasticity (MOE) of 1975 N mm-2, and a modulus of rupture (MOR) of 11.80 N mm-2. The dimensional stability of the fabricated particleboards does not follow the standard requirements; however, further study might be helpful for using the chemically modified bone adhesive as a biobased adhesive.
  4. Isaacs M, Garcia-Navarro J, Ong WJ, Jiménez-Calvo P
    Glob Chall, 2023 Mar;7(3):2200165.
    PMID: 36910466 DOI: 10.1002/gch2.202200165
    Energy security concerns require novel greener and more sustainable processes, and Paris Agreement goals have put in motion several measures aligned with the 2050 roadmap strategies and net zero emission goals. Renewable energies are a promising alternative to existing infrastructures, with solar energy one of the most appealing due to its use of the overabundant natural source of energy. Photocatalysis as a simple heterogeneous surface catalytic reaction is well placed to enter the realm of scaling up processes for wide scale implementation. Inspired by natural photosynthesis, artificial water splitting's beauty lies in its simplicity, requiring only light, a catalyst, and water. The bottlenecks to producing a high volume of hydrogen  are several: Reactors with efficient photonic/mass/heat profiles, multifunctional efficient solar-driven catalysts, and proliferation of pilot devices. Three case studies, developed in Japan, Spain, and France are showcased to emphasize efforts on a pilot and large-scale examples. In order for solar-assisted photocatalytic H2 to mature as a solution, the aforementioned bottlenecks must be overcome for the field to advance its technology readiness level, assess the capital expenditure, and enter the market.
  5. Yew M, Ren Y, Koh KS, Sun C, Snape C
    Glob Chall, 2019 Jan;3(1):1800060.
    PMID: 31565355 DOI: 10.1002/gch2.201800060
    Microfluidic systems have advanced beyond natural and life science applications and lab-on-a-chip uses. A growing trend of employing microfluidic technologies for environmental detection has emerged thanks to the precision, time-effectiveness, and cost-effectiveness of advanced microfluidic systems. This paper reviews state-of-the-art microfluidic technologies for environmental applications, such as on-site environmental monitoring and detection. Microdevices are extensively used in collecting environmental samples as a means to facilitate detection and quantification of targeted components with minimal quantities of samples. Likewise, microfluidic-inspired approaches for separation and treatment of contaminated water and air, such as the removal of heavy metals and waterborne pathogens from wastewater and carbon capture are also investigated.
  6. Melvin GJH, Wang Z, Morimoto S, Fujishige M, Takeuchi K, Hashimoto Y, et al.
    Glob Chall, 2019 Aug;3(8):1800107.
    PMID: 31565389 DOI: 10.1002/gch2.201800107
    Graphite whiskers (GWs) are obtained from coffee grounds (CGs) treated at 2500 °C for 1 h in the presence of Ar gas at 1 atm. The majority of the GWs formed inside the CGs shell are rod-like with a conical tip with diameter and length in the range between 1 to 3 µm and 4 to 10 µm, respectively. At first, the carbon layer might be grown in a turbostratic manner, and then progressively graphitized at higher temperature. The strong G' peak intensity might be induced by the disclination of graphitized carbon layers.
  7. Melvin GJH, Wang Z, Ni QQ
    Glob Chall, 2019 Nov;3(11):1900045.
    PMID: 31693011 DOI: 10.1002/gch2.201900045
    Agricultural wastes such as rice husks (RHs) are valuable due to their feasibility to be converted into carbon materials, low cost, and abundancy in contrast to the conventional carbon material sources. In this study, RHs are carbonized at various temperatures from low to high temperatures, and their electromagnetic (EM) wave absorption properties are evaluated. Carbon materials, silicon carbide (SiC) whiskers, and SiC particles are obtained from RHs carbonized at 1500 °C (CRH1500) for 0.5 h with presence of Ar gas at 1 atm. In order to evaluate their EM wave absorption performance, complex permittivity and permeability are measured by using vector network analyzer, and the values are utilized in the reflection loss (R.L.) calculation according to the transmission line theory. CRH1500, 40 wt% with thickness of 1.6 mm exhibits minimum R.L. of ≈-55.4 dB (>99.9997% absorption) at 11.37 GHz and response bandwidth (R.L. < 10 dB, > 90% absorption) of 4.21 GHz. Low-cost and abundant RHs, carbonized at various temperatures, show significant absorption performance. Their absorption performance and response bandwidth are highly dependent on matching thickness, indicating that they can be easily modulated for promising electromagnetic wave absorber materials.
  8. Ismail Z, Go YI
    Glob Chall, 2021 May;5(5):2000036.
    PMID: 33976904 DOI: 10.1002/gch2.202000036
    Water is indispensable for human survival. Freshwater scarcity and unsustainable water are the main growing concerns in the world. It is estimated that about 800 million people worldwide do not have basic access to drinking water and about 2.2 billion people do not have access to safe water supply. Southeast Asia is most likely to experience water scarcity and water demand as a result of climate change. Climate change and the increasing water demand that eventually contribute to water scarcity are focused upon here. For Southeast Asia to adapt to the adverse consequences of global climate change and the growing concern of environmental water demand, fog water harvesting is considered as the most promising method to overcome water scarcity or drought. Fog water collection technique is a passive, low maintenance, and sustainable option that can supply fresh drinking water to communities where fog is a common phenomenon. Fog water harvesting system involves the use of mesh nets to collect water as fog passes through them. Only minimal cost is required for the operation and maintenance. In conclusion, fog water harvesting seems to be a promising method that can be implemented to overcome water scarcity and water demand in Southeast Asia.
  9. Sulaiman RNR, Bakar AA, Ngadi N, Kahar INS, Nordin AH, Ikram M, et al.
    Glob Chall, 2023 Aug;7(8):2300047.
    PMID: 37635702 DOI: 10.1002/gch2.202300047
    Microplastic pollution has adversely affected the aquatic ecosystem, living creatures, and human health. Several studies in Malaysia have provided baseline information on the existence of microplastics in surface water, ingestion by marine life and sediment. Also, humans are exposed to microplastic due to consumption of contaminated abiotic and biotic products, such as processed seafood. Nonetheless, knowledge is still scarce among Malaysian on the potential remediation and pollution management of microplastics, which poses a significant challenge to preserve a good environmental status. Green technologies also other alternative to mitigate the contamination of microplastics for sustainable future. Hence, this review aims to provide an overview of microplastic's occurrence, fate, and implications in Malaysia's aquatic environment. Detection of microplastics from the water surface, ingestion by aquatics, and sediment samples are highlighted. Available different treatment processes toward microplastic remediation are also discussed. Additionally, the potential challenges, current perspective for plastic management in Malaysia, as well as green strategies for reducing microplastic contamination are also put forward. The goal of this work is to improve the understanding of the seriousness of microplastic contamination in aquatic environments, thus encouraging key concerns that need to be investigated further.
  10. Poudel P, Sharma S, Ansari MNM, Vaish R, Kumar R, Ibrahim SM, et al.
    Glob Chall, 2023 Apr;7(4):2100140.
    PMID: 37020619 DOI: 10.1002/gch2.202100140
    This paper presents a piezoelectric wind energy harvester that operates by a galloping mechanism with different shaped attachments attached to a bluff body. A comparison is made between harvesters that consist of different shaped attachments on a bluff body; these include triangular, circular, square, Y-shaped, and curve-shaped attachments. Simulation of the pressure field and the velocity field variation around the different shaped bluff bodies is performed and it is found that a high pressure difference creates a high lift force on the bluff body with curve-shaped attachments. A theoretical model based on a galloping mechanism is presented, which is verified by experiments. It is observed that the proposed harvester with curve-shaped attachments provides the best performance, where the harvester with a curve-shaped attachments provides the highest voltage and power output compared to the other shaped harvesters examined in this study. This paper provides a new concept for improving the power performance of the piezoelectric wind energy harvesters with modifications made on the bluff body.
  11. Sarkar SM, Dhar BK, Fahlevi M, Ahmed S, Hossain MJ, Rahman MM, et al.
    Glob Chall, 2023 Aug;7(8):2200246.
    PMID: 37635700 DOI: 10.1002/gch2.202200246
    The climate of the Earth has changed throughout history. Climate change negatively impacts human rights in a wide range of ways. The study aims to find out the impact of climate change on aging health in developing countries. The study found that public health will be devastated if climate change continues unabated. Countries that are least responsible for global warming are most susceptible to the effects of higher temperatures, such as death and disease. In low- and middle-income countries, disasters are more likely to happen to people aged 60 and over. Although climate change affects all of us, older people are especially at risk from it, as evidenced by a growing body of research. The study also offers countermeasures and suggestions to develop aging health in developing countries affected by climate change.
  12. Imam MU, Ismail M
    Glob Chall, 2017 Nov 16;1(8):1700043.
    PMID: 31565292 DOI: 10.1002/gch2.201700043
    Noncommunicable chronic diseases (NCCDs) are the leading causes of morbidity and mortality globally. The mismatch between present day diets and ancestral genome is suggested to contribute to the NCCDs burden, which is promoted by traditional risk factors like unhealthy diets, physical inactivity, alcohol and tobacco. However, epigenetic evidence now suggests that cumulatively inherited epigenetic modifications may have made humans more prone to the effects of present day lifestyle factors. Perinatal starvation was widespread in the 19th century. This together with more recent events like increasing consumption of western and low fiber diets, smoking, harmful use of alcohol, physical inactivity, and environmental pollutants may have programed the human epigenome for higher NCCDs risk. In this review, on the basis of available epigenetic data it is hypothesized that transgenerational effects of lifestyle factors may be contributing to the current global burden of NCCDs. Thus, there is a need to reconsider prevention strategies so that the subsequent generations will not have to pay for our sins and those of our ancestors.
  13. Sundararajan N, Habeebsheriff HS, Dhanabalan K, Cong VH, Wong LS, Rajamani R, et al.
    Glob Chall, 2024 Jan;8(1):2300187.
    PMID: 38223890 DOI: 10.1002/gch2.202300187
    Green nanotechnology, an emerging field, offers economic and social benefits while minimizing environmental impact. Nanoparticles, pivotal in medicine, pharmaceuticals, and agriculture, are now sourced from green plants and microorganisms, overcoming limitations of chemically synthesized ones. In agriculture, these green-made nanoparticles find use in fertilizers, insecticides, pesticides, and fungicides. Nanofertilizers curtail mineral losses, bolster yields, and foster agricultural progress. Their biological production, preferred for environmental friendliness and high purity, is cost-effective and efficient. Biosensors aid early disease detection, ensuring food security and sustainable farming by reducing excessive pesticide use. This eco-friendly approach harnesses natural phytochemicals to boost crop productivity. This review highlights recent strides in green nanotechnology, showcasing how green-synthesized nanomaterials elevate crop quality, combat plant pathogens, and manage diseases and stress. These advancements pave the way for sustainable crop production systems in the future.
  14. Khan R, Go Y
    Glob Chall, 2020 Feb;4(2):1900060.
    PMID: 32042443 DOI: 10.1002/gch2.201900060
    Malaysia targets to become the second-largest producer of solar photovoltaic (PV) in the world by increasing the current output from 12% to 20% in 2020. The government also expects to achieve 45% reduction of greenhouse gas emission by 2030 through renewable energy mainly by solar PV. Large-scale solar (LSS) aims to produce 2.5 GW, which contributes to 10% of the nation's electricity demands. The LSS system is held back by the grid-scale integration, transmission, and distribution infrastructure. Thus, power system analysis is crucial to achieve optimization in LSS to power grid integration. This paper investigates various power system analysis models and recommends an optimized configuration based on Malaysia's LSS scenario. In stage 1, an optimal PV sizing is carried out based on real data of LSS installation in different locations. In stage 2, power analysis is carried out using to analyze the potential difference variation when connected to a nine-bus power system. The potential variation at each bus of the system is assessed and hence provides a feasibility statement on the most effective configurations for LSS-grid integration. This paper serves as the reference model for LSS-grid integration in Malaysia and is expected to be replicated in the other countries with similar conditions.
  15. Mohanan M, Go YI
    Glob Chall, 2020 Apr;4(4):1900093.
    PMID: 32257382 DOI: 10.1002/gch2.201900093
    A large-scale solar photovoltaic system (LSS PV) aims to reduce the gap as Malaysia plans to shift electricity generation from conventional sources like fossil fuels to renewable energy sources. The government plans to increase renewable energy to 20% of the generation mix by 2025. The first and second round of Malaysia's LSS programme has 958 MW of PV projects to be realized by 2020. The third round of the LSS program goes for an aggregate capacity of 500 MW. Being an intermittent source of energy, the major complication is with grid integration of the LSS PV system into the national power grid. This research aims to identify an optimum power system management scheme for LSS in Malaysia to stabilize voltage fluctuations by utilizing IEEE bus configuration. The simulation and planning of network type is based on PSS/E and PVSyst. The expected outcome of this research is to develop a solution for LSS grid integration with minimal loss in the system and in accordance with electricity standards as per Malaysian grid code. Additionally, the harmony of incorporating power electronic devices for reactive power compensation is tested. This work can be stated as a reference model for utility provider in other countries having similar network and grid configuration.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links