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  1. Twin pregnancy -- a study of the local pattern
    Teoh SK, Wong WP
    Med J Malaysia, 1977 Sep;32(1):90-5.
    PMID: 609353
  2. Physiological weight changes in pregnancy in Malaysian women
    Sinnathuray TA, Wong WP
    Aust N Z J Obstet Gynaecol, 1972 May;12(2):122-5.
    PMID: 4509097
  3. The pattern of physiological changes in pregnancy in Malaysian women
    Sinnathuray TA, Wong WP
    Med J Malaya, 1971 Mar;25(3):182-6.
    PMID: 4253244
  4. Fulltext Clomid induced combined extrauterine and intrauterine pregnancy--a case report
    Ng YT, Wong WP, Puraviappan AP
    Med J Malaysia, 1983 Jun;38(2):150-2.
    PMID: 6621446
    A 23 year old Indian lady, gravida 1 para 0, with Clomid induced pregnancy was admitted to the University Hospital on 29 August 1981 with signs and symptoms of pregnancy and intraperitoneal bleed. Period ofamenorrhoea at time of admission was eight weeks. Emergency laparotomy revealed a right leaking ectopic pregnancy and an enlarged gravid uterus. Ultrasound done on the 7th post operative day confirmed concurrent intrauterine pregnancy which progressed normally to term, ending with a normal healthy baby at 39 weeks through an assisted breech delivery.
  5. Eclampsia - a review of 48 cases
    Ong SK, Foo J, Wong WP, Yusof K
    Med J Malaysia, 1978 Mar;32(3):206-11.
    PMID: 683043
  6. Characteristics of normal labour among different racial groups in Malaysia
    Lim MA, Wong WP, Sinnathuray TA
    Br J Obstet Gynaecol, 1977 Aug;84(8):600-4.
    PMID: 889748
    The characteristics of normal labour in 977 Malay, Chinese and Indian parturients were established from a retrospective study. Indian babies were found to be significantly smaller than Malay babies which were significantly smaller than Chinese babies (P less than 0-05, P less than 0-05). The mean duration of the first stage of labour taken from the time of admission to the labour ward was 3-4 hours in primiparae and 2-7 hours in multiparae. The mean durations of the second stage of labour were 23-7 minutes and 13-1 minutes respectively. Curves of mean dilatation of cervix and probit analysis at 80% revealed significant differences in the progress of normal labour in primiparae among the three racial groups. The Indian primiparae not only had a slower rate of cervical dilatation but seemed to reach the accelerated phase of dilatation later. No significant differences were noticed in the labours of multiparae.
  7. A comparison of trimethoprim-sulphamethoxazole and penicillin-streptomycin in the treatment of gynaecological infections
    Wong WP, Ng KH, Chai KH
    Med J Malaysia, 1973 Dec;28(2):125-7.
    PMID: 4276230
  8. Fulltext An Application of Machine Learning to Logistics Performance Prediction: An Economics Attribute-Based of Collective Instance
    Jomthanachai S, Wong WP, Khaw KW
    Comput Econ, 2023 Feb 01.
    PMID: 36747892 DOI: 10.1007/s10614-023-10358-7
    In this work, a machine learning application was constructed to predict the logistics performance index based on economic attributes. The prediction procedure employs both linear and non-linear machine learning algorithms. The macroeconomic panel dataset is used in this investigation. Furthermore, it was combined with the microeconomic panel dataset obtained through the data envelopment analysis method for evaluating financial efficiency. The procedure was implemented in six ASEAN member countries. The non-linear algorithm of an artificial neural network performed best on the complex pattern of a collective instance of these six countries, followed by the penalized linear of the Ridge regression method. Due to the limited amount of training data for each country, the artificial neural network prediction procedure is only applicable to the datasets of Singapore, Malaysia, and the Philippines. Ridge regression fits the Indonesia, Thailand and Vietnam datasets. The results provide precise trend forecasting. Macroeconomic factors are driving up the logistics performance index in Vietnam in 2020. Malaysia logistics performance is influenced by the logistics business's financial efficiency. The results at the country level can be used to track, improve, and reform the country's short-term logistics and supply chain policies. This can bring significant gains in national logistics and supply chain capabilities, as well as support for global trade collaboration, all for the long-term development of the region.
  9. A study of menstrual patterns following laparoscopic sterilization with silastic rings
    Goh TH, Puvan IS, Wong WP, Sivanesaratnam V, Sinnathuray TA
    Int. J. Fertil., 1981;26(2):116-9.
    PMID: 6114062
    The menstrual patterns of 281 women undergoing laparoscopic sterilization with silastic rings were studied prospectively. A significant increase in dysmenorrhea and irregular periods was seen soon after sterilization but this was transient, returning to presterilization levels by 12 months. Menorrhagia was not observed and the amount of menstrual blood loss showed a trend towards normal following sterilization. No permanent adverse effects on menstrual patterns were seen in the 1st year after sterilization. It is suggested that factors other than the sterilization procedure may be responsible for the high prevalence of menstrual dysfunction that has been reported following sterilization.
  10. Fulltext Enhanced tribological properties of diesel-based engine oil through synergistic MoS2-graphene nanohybrid additive
    Nagarajan T, Sridewi N, Wong WP, Walvekar R, Khalid M
    Sci Rep, 2023 Oct 13;13(1):17424.
    PMID: 37833323 DOI: 10.1038/s41598-023-43260-1
    This research explores the potential of microwave-synthesized MoS2-graphene nanohybrid as additives to enhance the tribological properties of diesel-based engine oil. The synthesis method offers significant advantages, reducing both synthesis time and energy consumption by 90-98% compared to conventional approaches. The synthesized nanohybrids are characterized through FESEM, EDX, XRD, and Raman spectroscopy to understand their morphology and functional group interactions. These nanohybrids are incorporated into 20W40 engine oil following synthesis, and a comprehensive assessment of their properties is conducted. This evaluation covers critical parameters like viscosity index, stability, volatility, as well as tribological properties, oxidation resistance, and thermal conductivity of the oil-nanohybrid system. Results demonstrate that adding just 0.05 wt% of MoS2-graphene nanohybrid leads to a remarkable 58.82% reduction in friction coefficient and a significant 36.26% decrease in the average wear scar diameter. Additionally, oxidation resistance improves by 19.21%, while thermal conductivity increases notably by 19.83% (at 100 °C). The study demonstrates the synergistic effects of these nanohybrids in reducing friction and wear, enhancing oxidation resistance, and improving thermal conductivity. In conclusion, this research highlights the potential of microwave-synthesized MoS2-graphene nanohybrid as promising tribological additives for diesel engine oils. Their successful integration could significantly enhance the performance and durability of critical mechanical components in diesel engines, representing a significant advancement in lubrication technology.
  11. Nitrogen metabolism and excretion in the aquatic chinese soft-shelled turtle, Pelodiscus sinensis, exposed to a progressive increase in ambient salinity
    Lee SM, Wong WP, Hiong KC, Loong AM, Chew SF, Ip YK
    J. Exp. Zoolog. Part A Comp. Exp. Biol., 2006 Dec 1;305(12):995-1009.
    PMID: 17068799
    This study aimed to determine effects of 6-day progressive increase in salinity from 1 per thousand to 15 per thousand on nitrogen metabolism and excretion in the soft-shelled turtle, Pelodiscus sinensis. For turtles exposed to 15 per thousand water on day 6, the plasma osmolality and concentrations of Na+, Cl- and urea increased significantly, which presumably decreased the osmotic loss of water. Simultaneously, there were significant increases in contents of urea, certain free amino acids (FAAs) and water-soluble proteins that were involved in cell volume regulation in various tissues. There was an apparent increase in proteolysis, releasing FAAs as osmolytes. In addition, there might be an increase in catabolism of certain amino acids, producing more ammonia. The excess ammonia was retained as indicated by a significant decrease in the rate of ammonia excretion on day 4 in 15 per thousand water, and a major portion of it was converted to urea. The rate of urea synthesis increased 1.4-fold during the 6-day period, although the capacity of the hepatic ornithine urea cycle remained unchanged. Urea was retained for osmoregulation because there was a significant decrease in urea excretion on day 4. Increased protein degradation and urea synthesis implies greater metabolic demands, and indeed turtles exposed to 15 per thousand water had significantly higher O2 consumption rate than the freshwater (FW) control. When turtles were returned from 15 per thousand water to FW on day 7, there were significant increases in ammonia (probably released through increased amino acid catabolism) and urea excretion, confirming that FAAs and urea were retained for osmoregulatory purposes in brackish water.
  12. Fulltext The Effects of Mindfulness on Older Adults with Mild Cognitive Impairment
    Wong WP, Coles J, Chambers R, Wu DB, Hassed C
    J Alzheimers Dis Rep, 2017 Dec 02;1(1):181-193.
    PMID: 30480237 DOI: 10.3233/ADR-170031
    Background: The current lack of an effective cure for dementia would exacerbate its prevalence and incidence globally. Growing evidence has linked mindfulness to cognitive and psychological improvements that could be relevant for mild cognitive impairment (MCI).

    Objective: To investigate whether mindfulness practice can improve health outcomes of MCI.

    Methods: The study is the first longitudinal mixed-methods observational study with a one-year follow-up period, that customized an eight-week group-based mindfulness training program for older adults with MCI (n = 14). Measures included cognitive function, psychological health, trait mindfulness, adherence to mindfulness practice, and everyday activities functioning as assessed at pre-intervention, post-intervention, and one-year follow-up. Repeated measures ANOVAs, Pearson's correlation analyses, and Mann-Whitney U tests were performed.

    Results: The MCI participants showed significant improvements in cognitive function (p 

  13. Chronic and acute ammonia toxicity in mudskippers, Periophthalmodon schlosseri and Boleophthalmus boddaerti: brain ammonia and glutamine contents, and effects of methionine sulfoximine and MK801
    Ip YK, Leong MW, Sim MY, Goh GS, Wong WP, Chew SF
    J Exp Biol, 2005 May;208(Pt 10):1993-2004.
    PMID: 15879078
    The objective of this study was to elucidate if chronic and acute ammonia intoxication in mudskippers, Periophthalmodon schlosseri and Boleophthalmus boddaerti, were associated with high levels of ammonia and/or glutamine in their brains, and if acute ammonia intoxication could be prevented by the administration of methionine sulfoximine [MSO; an inhibitor of glutamine synthetase (GS)] or MK801 [an antagonist of N-methyl D-aspartate type glutamate (NMDA) receptors]. For P. schlosseri and B. boddaerti exposed to sublethal concentrations (100 and 8 mmol l(-1) NH4Cl, respectively, at pH 7.0) of environmental ammonia for 4 days, brain ammonia contents increased drastically during the first 24 h, and they reached 18 and 14.5 micromol g(-1), respectively, at hour 96. Simultaneously, there were increases in brain glutamine contents, but brain glutamate contents were unchanged. Because glutamine accumulated to exceptionally high levels in brains of P. schlosseri (29.8 micromol g(-1)) and B. boddaerti (12.1 micromol g(-1)) without causing death, it can be concluded that these two mudskippers could ameliorate those problems associated with glutamine synthesis and accumulation as observed in patients suffering from hyperammonemia. P. schlosseri and B. boddaerti could tolerate high doses of ammonium acetate (CH3COONH4) injected into their peritoneal cavities, with 24 h LC50 of 15.6 and 12.3 micromol g(-1) fish, respectively. After the injection with a sublethal dose of CH3COONH4 (8 micromol g(-1) fish), there were significant increases in ammonia (5.11 and 8.36 micromol g(-1), respectively) and glutamine (4.22 and 3.54 micromol g(-1), respectively) levels in their brains at hour 0.5, but these levels returned to normal at hour 24. By contrast, for P. schlosseri and B. boddaerti that succumbed within 15-50 min to a dose of CH3COONH4 (15 and 12 micromol g(-1) fish, respectively) close to the LC50 values, the ammonia contents in the brains reached much higher levels (12.8 and 14.9 micromol g(-1), respectively), while the glutamine level remained relatively low (3.93 and 2.67 micromol g(-1), respectively). Thus, glutamine synthesis and accumulation in the brain was not the major cause of death in these two mudskippers confronted with acute ammonia toxicity. Indeed, MSO, at a dosage (100 microg g(-1) fish) protective for rats, did not protect B. boddaerti against acute ammonia toxicity, although it was an inhibitor of GS activities from the brains of both mudskippers. In the case of P. schlosseri, MSO only prolonged the time to death but did not reduce the mortality rate (100%). In addition, MK801 (2 microg g(-1) fish) had no protective effect on P. schlosseri and B. boddaerti injected with a lethal dose of CH3COONH4, indicating that activation of NMDA receptors was not the major cause of death during acute ammonia intoxication. Thus, it can be concluded that there are major differences in mechanisms of chronic and acute ammonia toxicity between brains of these two mudskippers and mammalian brains.
  14. Postprandial increases in nitrogenous excretion and urea synthesis in the giant mudskipper Periophthalmodon schlosseri
    Ip YK, Lim CK, Lee SL, Wong WP, Chew SF
    J Exp Biol, 2004 Aug;207(Pt 17):3015-23.
    PMID: 15277556
    The objective of this study was to determine the effects of feeding on the excretory nitrogen (N) metabolism of the giant mudskipper, Periophthalmodon schlosseri, with special emphasis on the role of urea synthesis in ammonia detoxification. The ammonia and urea excretion rates of P. schlosseri increased 1.70- and 1.92-fold, respectively, within the first 3 h after feeding on guppies. Simultaneously, there were significant decreases in ammonia levels in the plasma and the brain, and in urea contents in the muscle and liver, of P. schlosseri at 3 h post-feeding. Thus, it can be concluded that P. schlosseri was capable of unloading ammonia originally present in some of its tissues in anticipation of ammonia released from the catabolism of excess amino acids after feeding. Subsequently, there were significant increases in urea content in the muscle, liver and plasma (1.39-, 2.17- and 1.62-fold, respectively) at 6 h post-feeding, and the rate of urea synthesis apparently increased 5.8-fold between 3 h and 6 h. Increased urea synthesis might have occurred in the liver of P. schlosseri because the greatest increase in urea content was observed therein. The excess urea accumulated in the body at 6 h was completely excreted between 6 and 12 h, and the percentage of waste-N excreted as urea-N increased significantly to 26% during this period, but never exceeded 50%, the criterion for ureotely, meaning that P. schlosseri remained ammonotelic after feeding. By 24 h, 62.7% of the N ingested by P. schlosseri was excreted, out of which 22.6% was excreted as urea-N. This is the first report on the involvement of increased urea synthesis and excretion in defense against ammonia toxicity in the giant mudskipper, and our results suggest that an ample supply of energy resources, e.g. after feeding, is a prerequisite for the induction of urea synthesis. Together, increases in nitrogenous excretion and urea synthesis after feeding effectively prevented a postprandial surge of ammonia in the plasma of P. schlosseri as reported previously for other fish species. Consequently, contrary to previous reports, there were significant decreases in the ammonia content of the brain of P. schlosseri throughout the 24 h period post-feeding, accompanied by a significant decrease in brain glutamine content between 12 h and 24 h.
  15. Fulltext Optimal Computing Budget Allocation for Particle Swarm Optimization in Stochastic Optimization
    Zhang S, Xu J, Lee LH, Chew EP, Wong WP, Chen CH
    IEEE Trans Evol Comput, 2017 Apr;21(2):206-219.
    PMID: 29170617 DOI: 10.1109/TEVC.2016.2592185
    Particle Swarm Optimization (PSO) is a popular metaheuristic for deterministic optimization. Originated in the interpretations of the movement of individuals in a bird flock or fish school, PSO introduces the concept of personal best and global best to simulate the pattern of searching for food by flocking and successfully translate the natural phenomena to the optimization of complex functions. Many real-life applications of PSO cope with stochastic problems. To solve a stochastic problem using PSO, a straightforward approach is to equally allocate computational effort among all particles and obtain the same number of samples of fitness values. This is not an efficient use of computational budget and leaves considerable room for improvement. This paper proposes a seamless integration of the concept of optimal computing budget allocation (OCBA) into PSO to improve the computational efficiency of PSO for stochastic optimization problems. We derive an asymptotically optimal allocation rule to intelligently determine the number of samples for all particles such that the PSO algorithm can efficiently select the personal best and global best when there is stochastic estimation noise in fitness values. We also propose an easy-to-implement sequential procedure. Numerical tests show that our new approach can obtain much better results using the same amount of computational effort.
  16. Fulltext Synergistic performance evaluation of MoS2-hBN hybrid nanoparticles as a tribological additive in diesel-based engine oil
    Nagarajan T, Sridewi N, Wong WP, Walvekar R, Khanna V, Khalid M
    Sci Rep, 2023 Aug 02;13(1):12559.
    PMID: 37532805 DOI: 10.1038/s41598-023-39216-0
    In this study, MoS2-hBN hybrid nanoparticles were synthesized using an advanced microwave platform for new nanolubricant formulations. The synthesized nanoparticles were characterized by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and Raman spectroscopy. The hybrid nanoparticles were then introduced into a 20W40 diesel-based engine oil to produce a nanolubricant. The physical and chemical properties of the nanolubricant were investigated, including the viscosity index, stability, volatility, tribological properties, oxidation properties, and thermal conductivity. The results showed that the inclusion of 0.05 wt% MoS2-hBN hybrid nanoparticles in the oil significantly reduced the coefficient of friction and wear scar diameter by 68.48% and 35.54%, respectively. Moreover, it exhibited substantial oxidation and thermal conductivity improvement of 38.76% and 28.30%, respectively, at 100 °C. These findings demonstrate the potential of MoS2-hBN hybrid nanoparticles as an effective additive to enhance the properties of nanolubricant significantly. Furthermore, this study offers valuable insights into the underlying mechanisms responsible for the observed enhancements. The promising outcomes of this investigation contribute to the advancement of nanotechnology-based lubricants, showcasing their potential for improving engine efficiency and prolonging the lifespan of machinery.
  17. Fulltext Digitalization enhancement in the pharmaceutical supply network using a supply chain risk management approach
    Wong WP, Saw PS, Jomthanachai S, Wang LS, Ong HF, Lim CP
    Sci Rep, 2023 Dec 15;13(1):22287.
    PMID: 38097696 DOI: 10.1038/s41598-023-49606-z
    One major issue in pharmaceutical supply chain management is the supply shortage, and determining the root causes of medicine shortages necessitates an in-depth investigation. The concept of risk management is proposed in this study to identify significant risk factors in the pharmaceutical supply chain. Fuzzy failure mode and effect analysis and data envelopment analysis were used to evaluate the risks of the pharmaceutical supply chain. Based on a case study on the Malaysian pharmaceutical supply chain, it reveals that the pharmacy node is the riskiest link. The unavailability of medicine due to unexpected demand, as well as the scarcity of specialty or substitute drugs, pose the most significant risk factors. These risks could be mitigated by digital technology. We propose an appropriate digital technology platform consisting of big data analytics and blockchain technologies to undertake these challenges of supply shortage. By addressing risk factors through the implementation of a digitalized supply chain, organizations can fortify their supply networks, fostering resilience and efficiency, and thereby playing a pivotal role in advancing the Pharma 4.0 era.
  18. Microwave-assisted upcycling of plastic waste to high-performance carbon anode for lithium-ion batteries
    Mohd Abdah MAA, Mohammad Azlan FN, Wong WP, Mustafa MN, Walvekar R, Khalid M
    Chemosphere, 2024 Feb;349:140973.
    PMID: 38122940 DOI: 10.1016/j.chemosphere.2023.140973
    The increasing demand for high-performance lithium-ion batteries (LIBs) has emphasized the need for affordable and sustainable materials, prompting the exploration of waste upcycling to address global sustainability challenges. In this study, we efficiently converted polypropylene (PP) plastic waste from used centrifuge tubes into activated polypropylene carbon (APC) using microwave-assisted pyrolysis. The synthesis of APC was optimized using response surface methodology/central composite design (RSM/CCD). Based on the RSM results, the optimal conditions for PP plastic conversion into carbon were determined as follows: HNO3 concentration of 3.5 M, microwave temperature of 230 °C, and holding time of 25 min. Under these conditions, the obtained intensity ratio of Id/Ig in PP carbon was 0.681 ± 0.013, with an error of 6.81 ± 0.013 % between predicted and actual values. The physicochemical studies, including FESEM-EDX, XRD, and Raman spectroscopy, confirmed the successful synthesis of APC samples. The APC 800 material exhibited a well-organized three-dimensional structure characterized by large pores and mesopores, enabling fast ion transport in the electrode. As a result, the APC 800 electrode demonstrated an initial discharge capacity of 381.0 mAh/g, an improved initial coulombic efficiency of 85.1%, and excellent cycling stability after 100 cycles. Notably, the APC 800 electrode displayed remarkable rate performance, showing a reversible capacity of 355.1 mAh/g when the current density was reset to 0.2 A/g, highlighting its high electrochemical reversibility. The outstanding characteristics of APC 800 as an anode electrode material for high-performance lithium-ion batteries suggest a promising future for its application in the field.
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