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Fulltext An effective and novel pore sealing agent to enhance the corrosion resistance performance of Al coating in artificial ocean water

Lee HS, Singh JK, Ismail MA

Sci Rep, 2017 02 03;7:41935.
PMID: 28157233 DOI: 10.1038/srep41935

A new technique was accepted to fill the porosity of Al coating applied by arc thermal spray process to enhance corrosion resistance performance in artificial ocean water. The porosity is the inherent property of arc thermal spray coating process. In this study, applied coating was treated with different concentrations of ammonium phosphate mono basic (NH4H2PO4: AP) solution thereafter dried at room temperature and kept in humidity chamber for 7d to deposit uniform film. The corrosion resistance of Al coating and treated samples have been evaluated using electrochemical impedance spectroscopy (EIS) and potentiodynamic techniques with exposure periods in artificial ocean water. Electrochemical techniques, X-ray diffraction (XRD), Raman spectroscopy, atomic force microscopy (AFM) and field emission-scanning electron microscopy (FE-SEM) indicated that phosphate ion would have been retarding corrosion of Al coating effectively. The formation of AHP (Ammonium Aluminum Hydrogen Phosphate Hydrate: NH4)3Al5H6(PO4)8.18H2O) on Al coating surface after treatment with AP is nano sized, crystalline and uniformly deposited but after exposure them in artificial ocean water, they form AHPH (Aluminum hydroxide phosphate hydrate Al3(PO4)2(OH)3(H2O)5) that is very protective, adherent, uniform and plate like morphology of corrosion products. The AHPH is sparingly soluble and adherent to surface and imparted improved corrosion resistance.
Misdiagnosis of Ocular Adnexal Sporotrichosis: A Case Series

Param Jit Singh JK, Chewa Raja JS

Cureus, 2024 Oct;16(10):e71657.
PMID: 39553126 DOI: 10.7759/cureus.71657

Sporotrichosis is a subacute or chronic infection affecting subcutaneous tissues, caused by the dimorphic fungus Sporothrix spp. This case series discusses three instances of ocular adnexal sporotrichosis treated at a tertiary government hospital in Pahang, Malaysia. It highlights diagnostic challenges, management strategies, and the impact of misdiagnosis and underreporting in the Southeast Asian tropical region compared to other parts of the world. Two of the three cases were initially misdiagnosed, leading to delays in definitive treatment. Incisional biopsies were performed for histopathological and fungal culture analysis, with two cases confirming the presence of Sporothrix spp. Following diagnosis, all patients responded well to oral fluconazole, although the recovery duration varied. Ocular sporotrichosis can be misdiagnosed due to its resemblance to other ocular conditions. Prompt diagnosis and early treatment are crucial to accelerating recovery and minimizing the risk of long-term ocular complications.
Fulltext Protection of Reinforced Concrete Structures of Waste Water Treatment Reservoirs with Stainless Steel Coating Using Arc Thermal Spraying Technique in Acidified Water

Lee HS, Park JH, Singh JK, Ismail MA

Materials (Basel), 2016 Sep 03;9(9).
PMID: 28773875 DOI: 10.3390/ma9090753

Waste water treatment reservoirs are contaminated with many hazardous chemicals and acids. Reservoirs typically comprise concrete and reinforcement steel bars, and the main elements responsible for their deterioration are hazardous chemicals, acids, and ozone. Currently, a variety of techniques are being used to protect reservoirs from exposure to these elements. The most widely used techniques are stainless steel plating and polymeric coating. In this study, a technique known as arc thermal spraying was used. It is a more convenient and economical method for protecting both concrete and reinforcement steel bar from deterioration in waste water treatment reservoirs. In this study, 316L stainless steel coating was applied to a concrete surface, and different electrochemical experiments were performed to evaluate the performance of coatings in different acidic pH solutions. The coating generated from the arc thermal spraying process significantly protected the concrete surface from corrosion in acidic pH solutions, owing to the formation of a double layer capacitance-a mixture of Cr3+ enriched with Cr₂O₃ and Cr-hydroxide in inner and Fe3+ oxide on the outer layer of the coating. The formation of this passive film is defective owing to the non-homogeneous 316L stainless steel coating surface. In the pH 5 solution, the growth of a passive film is adequate due to the presence of un-dissociated water molecules in the aqueous sulfuric acid solution. The coated surface is sealed with alkyl epoxide, which acts as a barrier against the penetration of acidic solutions. This coating exhibits higher impedance values among the three studied acidic pH solutions.
Genetic modification in Malaysia and India: current regulatory framework and the special case of non-transformative RNAi in agriculture

Darsan Singh JK, Mat Jalaluddin NS, Sanan-Mishra N, Harikrishna JA

Plant Cell Rep, 2019 Dec;38(12):1449-1463.
PMID: 31350570 DOI: 10.1007/s00299-019-02446-6

Recent developments in modern biotechnology such as the use of RNA interference (RNAi) have broadened the scope of crop genetic modification. RNAi strategies have led to significant achievements in crop protection against biotic and abiotic stresses, modification of plant traits, and yield improvement. As RNAi-derived varieties of crops become more useful in the field, it is important to examine the capacity of current regulatory systems to deal with such varieties, and to determine if changes are needed to improve the existing frameworks. We review the biosafety frameworks from the perspective of developing countries that are increasingly involved in modern biotechnology research, including RNAi applications, and make some recommendations. Malaysia and India have approved laws regulating living modified organisms and products thereof, highlighting that the use of any genetically modified step requires regulatory scrutiny. In view of production methods for exogenously applied double-stranded RNAs and potential risks from the resulting double-stranded RNA-based products, we argue that a process-based system may be inappropriate for the non-transformative RNAi technology. We here propose that the current legislation needs rewording to take account of the non-transgenic RNAi technology, and discuss the best alternative for regulatory systems in India and Malaysia in comparison with the existing frameworks in other countries.
Fulltext Performance of Fly Ash Geopolymer Concrete Incorporating Bamboo Ash at Elevated Temperature

Ishak S, Lee HS, Singh JK, Ariffin MAM, Lim NHAS, Yang HM

Materials (Basel), 2019 Oct 17;12(20).
PMID: 31627479 DOI: 10.3390/ma12203404

This paper presents the experimental results on the behavior of fly ash geopolymer concrete incorporating bamboo ash on the desired temperature (200 °C to 800 °C). Different amounts of bamboo ash were investigated and fly ash geopolymer concrete was considered as the control sample. The geopolymer was synthesized with sodium hydroxide and sodium silicate solutions. Ultrasonic pulse velocity, weight loss, and residual compressive strength were determined, and all samples were tested with two different cooling approaches i.e., an air-cooling (AC) and water-cooling (WC) regime. Results from these tests show that with the addition of 5% bamboo ash in fly ash, geopolymer exhibited a 5 MPa (53%) and 5.65 MPa (66%) improvement in residual strength, as well as 940 m/s (76%) and 727 m/s (53%) greater ultrasonic pulse velocity in AC and WC, respectively, at 800 °C when compared with control samples. Thus, bamboo ash can be one of the alternatives to geopolymer concrete when it faces exposure to high temperatures.
Prostaglandin-endoperoxide synthase (PTGS2) and Defensin beta 1 (DEFB1) gene polymorphisms are not associated with periodontitis in Malays

Jagender Singh JK, Vaithilingam RD, Ng CC, Baharuddin NA, Hasnur Safii S, Rahman MT

Malays J Pathol, 2021 Dec;43(3):425-434.
PMID: 34958064

INTRODUCTION: In line with the association of prostaglandin-endoperoxide synthase 2 (PTGS2) and defensin beta 1 (DEFB1) single nucleotide polymorphisms (SNPs) with periodontitis among the Chinese and European populations, the current study was aimed to assess the same association among the Malays in Malaysia.
METHODS: Blood samples of individuals with periodontitis (PD) (n=72) and periodontally healthy (PH) (n=62) donors were obtained from Malaysian Periodontal Database and Biobanking system (MPDBS). Genomic DNA samples were analyzed for three PTGS2 SNPs (rs5275, rs20417, rs689466,) and one DEFB1 SNP (rs1047031) using Taqman SNP genotyping assays. Notably, rs20417 and rs689466 were located in the promoter region while rs5275 and rs1047031 were located in the 3' untranslated region of the transcript. Association between the SNPs and PD were then analyzed using genotypic association analysis (additive, dominant and recessive models).
RESULTS: The allelic frequency for the rs689466-G was higher in PD group (35.2%) compared that in PH group (29.0%). However, the association of rs689466-G and other SNPs with PD was not statistically significant (at 95% CI). No associations were observed for genotypic associations between the PTGS2 and DEFB1 SNPs with PD susceptibility.
CONCLUSIONS: PTGS2 (rs5275, rs20417, and rs689466) and DEFB1 (rs1047031) polymorphism was not associated with PD in Malays, unlike the Chinese, Taiwanese & European population. This suggests that other causal variants might be involved in the development and progression of PD among Malays.
Study on the Shielding Effectiveness of an Arc Thermal Metal Spraying Method against an Electromagnetic Pulse

Lee HS, Choe HB, Baek IY, Singh JK, Ismail MA

Materials (Basel), 2017 Oct 04;10(10).
PMID: 28976931 DOI: 10.3390/ma10101155

An electromagnetic pulse (EMP) explodes in real-time and causes critical damage within a short period to not only electric devices, but also to national infrastructures. In terms of EMP shielding rooms, metal plate has been used due to its excellent shielding effectiveness (SE). However, it has difficulties in manufacturing, as the fabrication of welded parts of metal plates and the cost of construction are non-economical. The objective of this study is to examine the applicability of the arc thermal metal spraying (ATMS) method as a new EMP shielding method to replace metal plate. The experimental parameters, metal types (Cu, Zn-Al), and coating thickness (100-700 μm) used for the ATMS method were considered. As an experiment, a SE test against an EMP in the range of 103 to 1010 Hz was conducted. Results showed that the ATMS coating with Zn-Al had similar shielding performance in comparison with metal plate. In conclusion, the ATMS method is judged to have a high possibility of actual application as a new EMP shielding material.
Fulltext Optimization of Micro and Nano Palm Oil Fuel Ash to Determine the Carbonation Resistance of the Concrete in Accelerated Condition

Tang WL, Lee HS, Vimonsatit V, Htut T, Singh JK, Wan Hassan WNF, et al.

Materials (Basel), 2019 Jan 03;12(1).
PMID: 30609786 DOI: 10.3390/ma12010130

The carbonation rate of reinforced concrete is influenced by three parameters, namely temperature, relative humidity, and concentration of carbon dioxide (CO₂) in the surroundings. As knowledge of the service lifespan of reinforced concrete is crucial in terms of corrosion, the carbonation process is important to study, and high-performance durable reinforced concretes can be produced to prolong the effects of corrosion. To examine carbonation resistance, accelerated carbonation testing was conducted in accordance with the standards of BS 1881-210:2013. In this study, 10⁻30% of micro palm oil fuel ash (mPOFA) and 0.5⁻1.5% of nano-POFA (nPOFA) were incorporated into concrete mixtures to determine the optimum amount for achieving the highest carbonation resistance after 28 days water curing and accelerated CO₂ conditions up to 70 days of exposure. The effect of carbonation on concrete specimens with the inclusion of mPOFA and nPOFA was investigated. The carbonation depth was identified by phenolphthalein solution. The highest carbonation resistance of concrete was found after the inclusion of 10% mPOFA and 0.5% nPOFA, while the lowest carbonation resistance was found after the inclusion of 30% mPOFA and 1.5% nPOFA.
Fulltext Traditional Chinese Medicine Body Constitutions and Psychological Determinants of Depression among University Students in Malaysia: A Pilot Study

Yap SY, Foo CN, Lim YM, Ng FL, Mohd-Sidik S, Tang PY, et al.

Int J Environ Res Public Health, 2021 May 18;18(10).
PMID: 34069915 DOI: 10.3390/ijerph18105366

Depression is commonly observed in university students, who are a high risk group for developing psychiatric disorders during adulthood. This study aimed to determine the prevalence of depression and its traditional Chinese medicine body constitutions and psychological determinants among university students in Malaysia. A cross-sectional pilot study was conducted between 9 and 28 September 2020 among 80 university students in Malaysia. Participants completed online survey questionnaires, including the validated Patient Health Questionnaire (PHQ-9), Constitution in Chinese Medicine Questionnaire (CMCQ), Dysfunctional Attitude Scale (DAS), Depression Anxiety Stress Scale (DASS-21) stress subscale, Perceived Stress Scale (PSS-10), and Rosenberg Self-Esteem Scale (RSES), which assess depression, body constitution, dysfunctional attitude, stress, perceived stress, and self-esteem. Multiple linear regression analyses were performed to determine the associated risk factors for depression. The overall prevalence of depression among university students was 33.8%. The multiple regression analysis showed a significant relationship between depression and qi-stagnation constitution (B = 0.089, p = 0.011), balanced constitution (B = -0.077, p = 0.049), and self-esteem (B = -0.325, p = 0.001). Our findings suggest that some traditional Chinese medicine body constitutions and self-esteem are significant risk factors affecting depression among university students. Identifying risk factors of depression is vital to aid in the early detection of depression among university students.
Fulltext An evaluation of consumers' perceptions regarding "modern medicines" in penang, malaysia

Babar ZU, Hassali MA, Shyong TL, Hin TK, Cien CS, Bin LS, et al.

J Young Pharm, 2012 Apr;4(2):108-13.
PMID: 22754263 DOI: 10.4103/0975-1483.96625

The objective of this study was to evaluate consumers' perceptions regarding "modern medicines" in Penang, Malaysia. To conduct this exploratory study, qualitative techniques were used. Consumers more than 19 years of age and could speak English, who had visited a pharmacy in the last 30 days, were included from the four major areas of Penang. Eighteen interviews were conducted until the point of saturation. The interviews were audio-taped and then transcribed verbatim for thematic content analysis. Many consumers correctly identified the major characteristics and properties of modern medicines; however, others raised doubts regarding the safety, quality and efficacy of "modern medicines". There were many misconceptions such as "all modern medicines can cause dependence", traditional medicines are completely "free of side-effects" and "Western medicines cure while Chinese medicines don't". Color was also considered a strong determinant of the safety and characteristics of a medicine. Regarding consumers' "medicine information seeking behavior", many consumers would seek information from doctors and pharmacists; however, there were others, who would look for books, or get it from the internet and friends. Of concern many consumers emphasized that while "self-searching for drug information" they would only look for side-effects. Misconceptions regarding medicine-taking behavior, medicine use and compliance were also identified. Though several consumers complied with the medicine-taking instructions, many reported that they would stop taking medicines, once they feel better. Though many consumers correctly identified the characteristics of "modern medicines", misconceptions regarding "medicine information sources and "medicine-taking behavior" were rampant. The situation demands corrective actions including community-oriented educational campaigns to improve "medicine use" in the society.

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