Displaying publications 61 - 80 of 111 in total

Abstract:
Sort:
  1. Said S. E. H. Elnashaie
    MyJurnal
    Bifurcation and chaos are important phenomena affecting many physical and chemical systems. They are also related to the stability/instability and multiplicity phenomena associated with these systems. The phenomena are not only of theoretical/mathematical interest but are also important for laboratory, pilot plant and commercial units. This paper concentrates on 3 systems:

    1. The novel auto-thermic Circulating Fluidized Membrane Steam Reformer (CFBMSR) for the efficient production of the clean fuel hydrogen and which shows multiplicity of the steady state (static bifurcation)

    2. A novel fermentor for the efficient production of bio-ethanol that shows static/dynamic bifurcation as well as chaotic behaviour

    3. The neurocycle of the acetylcholine transmitter in the brain using diffusion-reaction models in order to gain insight into their possible connection to Alzheimer and Parkinson Diseases (AD/PD); these are preliminary efforts to investigate the bifurcation and chaotic behaviour of this neurocycle.
  2. Fulsom BG, Pedlar TK, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Dec 07;121(23):232001.
    PMID: 30576207 DOI: 10.1103/PhysRevLett.121.232001
    We report the observation of ϒ(2S)→γη_{b}(1S) decay based on an analysis of the inclusive photon spectrum of 24.7  fb^{-1} of e^{+}e^{-} collisions at the ϒ(2S) center-of-mass energy collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We measure a branching fraction of B[ϒ(2S)→γη_{b}(1S)]=(6.1_{-0.7-0.6}^{+0.6+0.9})×10^{-4} and derive an η_{b}(1S) mass of 9394.8_{-3.1-2.7}^{+2.7+4.5}  MeV/c^{2}, where the uncertainties are statistical and systematic, respectively. The significance of our measurement is greater than 7 standard deviations, constituting the first observation of this decay mode.
  3. Adachi I, Adye T, Ahmed H, Ahn JK, Aihara H, Akar S, et al.
    Phys Rev Lett, 2018 Dec 28;121(26):261801.
    PMID: 30636113 DOI: 10.1103/PhysRevLett.121.261801
    We present first evidence that the cosine of the CP-violating weak phase 2β is positive, and hence exclude trigonometric multifold solutions of the Cabibbo-Kobayashi-Maskawa (CKM) Unitarity Triangle using a time-dependent Dalitz plot analysis of B^{0}→D^{(*)}h^{0} with D→K_{S}^{0}π^{+}π^{-} decays, where h^{0}∈{π^{0},η,ω} denotes a light unflavored and neutral hadron. The measurement is performed combining the final data sets of the BABAR and Belle experiments collected at the ϒ(4S) resonance at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The data samples contain (471±3)×10^{6}BB[over ¯] pairs recorded by the BABAR detector and (772±11)×10^{6}BB[over ¯] pairs recorded by the Belle detector. The results of the measurement are sin2β=0.80±0.14(stat)±0.06(syst)±0.03(model) and cos2β=0.91±0.22(stat)±0.09(syst)±0.07(model). The result for the direct measurement of the angle β of the CKM Unitarity Triangle is β=[22.5±4.4(stat)±1.2(syst)±0.6(model)]°. The measurement assumes no direct CP violation in B^{0}→D^{(*)}h^{0} decays. The quoted model uncertainties are due to the composition of the D^{0}→K_{S}^{0}π^{+}π^{-} decay amplitude model, which is newly established by performing a Dalitz plot amplitude analysis using a high-statistics e^{+}e^{-}→cc[over ¯] data sample. CP violation is observed in B^{0}→D^{(*)}h^{0} decays at the level of 5.1 standard deviations. The significance for cos2β>0 is 3.7 standard deviations. The trigonometric multifold solution π/2-β=(68.1±0.7)° is excluded at the level of 7.3 standard deviations. The measurement resolves an ambiguity in the determination of the apex of the CKM Unitarity Triangle.
  4. Seong IS, Vahsen SE, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2019 Jan 11;122(1):011801.
    PMID: 31012694 DOI: 10.1103/PhysRevLett.122.011801
    We report on the first Belle search for a light CP-odd Higgs boson, A^{0}, that decays into low mass dark matter, χ, in final states with a single photon and missing energy. We search for events produced via the dipion transition ϒ(2S)→ϒ(1S)π^{+}π^{-}, followed by the on-shell process ϒ(1S)→γA^{0} with A^{0}→χχ, or by the off-shell process ϒ(1S)→γχχ. Utilizing a data sample of 157.3×10^{6} ϒ(2S) decays, we find no evidence for a signal. We set limits on the branching fractions of such processes in the mass ranges M_{A^{0}}<8.97  GeV/c^{2} and M_{χ}<4.44  GeV/c^{2}. We then use the limits on the off-shell process to set competitive limits on WIMP-nucleon scattering in the WIMP mass range below 5  GeV/c^{2}.
  5. Guan Y, Vossen A, Adachi I, Adamczyk K, Ahn JK, Aihara H, et al.
    Phys Rev Lett, 2019 Feb 01;122(4):042001.
    PMID: 30768311 DOI: 10.1103/PhysRevLett.122.042001
    We report the first observation of the spontaneous polarization of Λ and Λ[over ¯] hyperons transverse to the production plane in e^{+}e^{-} annihilation, which is attributed to the effect arising from a polarizing fragmentation function. For inclusive Λ/Λ[over ¯] production, we also report results with subtracted feed-down contributions from Σ^{0} and charm. This measurement uses a dataset of 800.4  fb^{-1} collected by the Belle experiment at or near a center-of-mass energy of 10.58 GeV. We observe a significant polarization that rises with the fractional energy carried by the Λ/Λ[over ¯] hyperon.
  6. Aad G, Abbott B, Abeling K, Abicht NJ, Abidi SH, Aboulhorma A, et al.
    Phys Rev Lett, 2024 Jan 12;132(2):021803.
    PMID: 38277607 DOI: 10.1103/PhysRevLett.132.021803
    The first evidence for the Higgs boson decay to a Z boson and a photon is presented, with a statistical significance of 3.4 standard deviations. The result is derived from a combined analysis of the searches performed by the ATLAS and CMS Collaborations with proton-proton collision datasets collected at the CERN Large Hadron Collider (LHC) from 2015 to 2018. These correspond to integrated luminosities of around 140  fb^{-1} for each experiment, at a center-of-mass energy of 13 TeV. The measured signal yield is 2.2±0.7 times the standard model prediction, and agrees with the theoretical expectation within 1.9 standard deviations.
  7. Lee RL, Ackerman SE
    Psychiatry, 1980 Feb;43(1):78-88.
    PMID: 7355184
    This discussion of an episode of mass hysteria in a Malay college in West Malaysia examines stress and conflict in relation to the interpretive process within a specific social setting. Unlike previous studies, which conceptualize mass hysteria as a cathartic response to accumulated stress, the present study treats stress as a matter of definition in a specific sociocultural context rather than as an objective given from which predictions can be made. Objections are raised to the logic of explanations that attribute mass hysteria to environmental stress. What is of concern is how meanings are assigned to events that are experienced as stressful, how participants and observers explain these events, and the consequences that follow from their interpretations.
  8. Lee RL, Ackerman SE
    Psychiatry, 1980 Feb;43(1):78-88.
    PMID: 27755901
  9. Abdullah N, Abdul Murad NA, Mohd Haniff EA, Syafruddin SE, Attia J, Oldmeadow C, et al.
    Public Health, 2017 Aug;149:31-38.
    PMID: 28528225 DOI: 10.1016/j.puhe.2017.04.003
    OBJECTIVE: Malaysia has a high and rising prevalence of type 2 diabetes (T2D). While environmental (non-genetic) risk factors for the disease are well established, the role of genetic variations and gene-environment interactions remain understudied in this population. This study aimed to estimate the relative contributions of environmental and genetic risk factors to T2D in Malaysia and also to assess evidence for gene-environment interactions that may explain additional risk variation.
    STUDY DESIGN: This was a case-control study including 1604 Malays, 1654 Chinese and 1728 Indians from the Malaysian Cohort Project.
    METHODS: The proportion of T2D risk variance explained by known genetic and environmental factors was assessed by fitting multivariable logistic regression models and evaluating McFadden's pseudo R(2) and the area under the receiver-operating characteristic curve (AUC). Models with and without the genetic risk score (GRS) were compared using the log likelihood ratio Chi-squared test and AUCs. Multiplicative interaction between genetic and environmental risk factors was assessed via logistic regression within and across ancestral groups. Interactions were assessed for the GRS and its 62 constituent variants.
    RESULTS: The models including environmental risk factors only had pseudo R(2) values of 16.5-28.3% and AUC of 0.75-0.83. Incorporating a genetic score aggregating 62 T2D-associated risk variants significantly increased the model fit (likelihood ratio P-value of 2.50 × 10(-4)-4.83 × 10(-12)) and increased the pseudo R(2) by about 1-2% and AUC by 1-3%. None of the gene-environment interactions reached significance after multiple testing adjustment, either for the GRS or individual variants. For individual variants, 33 out of 310 tested associations showed nominal statistical significance with 0.001 
  10. Khandaker MU, Abuzaid MM, Mohamed IA, Yousef M, Jastaniah S, Alshammari QT, et al.
    Radiat Phys Chem Oxf Engl 1993, 2023 Sep;210:111023.
    PMID: 37206369 DOI: 10.1016/j.radphyschem.2023.111023
    Radiological staff, especially radiographers, work as front liners against the COVID-19 outbreak. This study aims to assess compliance with radiation protection and infection control practices during COVID-19 mobile radiography procedures. This cross-sectional study included 234 radiographers (females, 56%, n = 131; males, 44%, n = 103) who were asked to complete an online questionnaire consisting of demographic data, radiation protection and infection control practices during COVID-19 portable cases, and knowledge and awareness. After informed consent was completed, SPSS statistical software was used for the data analysis. The most common age group of participants ranged from 18 to 25 years old (30.3%, n = 71). Bachelor's degree holders were 74.4% (n = 174). Most radiographers (39.7%, n = 93) had a working experience of 1-5 years, followed by 27.8% (n = 65) with more than 16 years of experience. Most respondents (62.4%, n = 146) handled approximately 1-5 cases daily, the majority of them (56%, n = 131) stated affirmatively they had obtained special training to handle COVID-19, and when inquired if they had received any special allowances for handling COVID-19 suspected/confirmed cases most of them stated negative (73.9%, n = 173). Most participants stated that they always wear a TLD during portable cases (67.1%, n = 157) and a lead apron (51.7%, n = 121). Around 73% (n = 171) knew the latest information on COVID-19 and attended the COVID-19 awareness course. A significant association was found between the work experience of the radiographers and their responses to following the best practices (p = 0.018, α = 0.05). Radiographers who had COVID-19 training (μ = 48.78) tend to adhere more to best practices than those who have not (p = 0.04, α = 0.05). Further, respondents who handled more than 16/more COVID-19 suspected/confirmed cases followed the best practices more (μ = 50.38) than those who handled less (p = 0.04, α = 0.05). This study revealed detailed information on radiation protection and infection control practices during COVID-19 mobile radiography. It has been observed that the participants/radiographers have good knowledge and awareness of radiation protection and infection-control practices. The present results may be used to plan future requirements regarding resources and training to ensure patient safety.
  11. Akram W, Hussein MS, Ahmad S, Mamat MN, Ismail NE
    Saudi Pharm J, 2015 Oct;23(5):499-503.
    PMID: 26594115 DOI: 10.1016/j.jsps.2015.01.011
    There is no instrument which collectively assesses the knowledge, attitude and perceived practice of asthma among community pharmacists. Therefore, this study aimed to validate the instrument which measured the knowledge, attitude and perceived practice of asthma among community pharmacists by producing empirical evidence of validity and reliability of the items using Rasch model (Bond & Fox software®) for dichotomous and polytomous data. This baseline study recruited 33 community pharmacists from Penang, Malaysia. The results showed that all PTMEA Corr were in positive values, where an item was able to distinguish between the ability of respondents. Based on the MNSQ infit and outfit range (0.60-1.40), out of 55 items, 2 items from the instrument were suggested to be removed. The findings indicated that the instrument fitted with Rasch measurement model and showed the acceptable reliability values of 0.88 and 0.83 and 0.79 for knowledge, attitude and perceived practice respectively.
  12. Alavi SE, Soltanian MR, Amiri IS, Khalily M, Supa'at AS, Ahmad H
    Sci Rep, 2016 Jan 27;6:19891.
    PMID: 26814621 DOI: 10.1038/srep19891
    5G communications require a multi Gb/s data transmission in its small cells. For this purpose millimeter wave (mm-wave) RF signals are the best solutions to be utilized for high speed data transmission. Generation of these high frequency RF signals is challenging in electrical domain therefore photonic generation of these signals is more studied. In this work, a photonic based simple and robust method for generating millimeter waves applicable in 5G access fronthaul is presented. Besides generating of the mm-wave signal in the 60 GHz frequency band the radio over fiber (RoF) system for transmission of orthogonal frequency division multiplexing (OFDM) with 5 GHz bandwidth is presented. For the purpose of wireless transmission for 5G application the required antenna is designed and developed. The total system performance in one small cell was studied and the error vector magnitude (EVM) of the system was evaluated.
  13. Amiri IS, Alavi SE, Soltanian MR, Fisal N, Supa'at AS, Ahmad H
    Sci Rep, 2015;5:11897.
    PMID: 26153536 DOI: 10.1038/srep11897
    This paper describes a novel technique to increase the numbers of access points (APs) in a wavelength division multiplexed-passive optical network (WDM-PON) integrated in a 100 GHz radio-over-fiber (RoF). Eight multi-carriers separated by 25 GHz intervals were generated in the range of 193.025 to 193.200 THz using a microring resonator (MRR) system incorporating an add-drop filter system. All optically generated multi-carriers were utilized in an integrated system of WDM-PON-RoF for transmission of four 43.6 Gb/sec orthogonal frequency division multiplexing (OFDM) signals. Results showed that an acceptable BER variation for different path lengths up to 25 km was achievable for all four access points and thus the transmission of four OFDM channels is feasible for a 25 km standard single mode fiber (SSMF) path length.
  14. Alavi SE, Soltanian MRK, Amiri IS, Khalily M, Supa'at ASM, Ahmad H
    Sci Rep, 2020 Jul 22;10(1):12147.
    PMID: 32699388 DOI: 10.1038/s41598-020-69377-1
    An amendment to this paper has been published and can be accessed via a link at the top of the paper.
  15. Ng CM, Badon SE, Dhivyalosini M, Hamid JJM, Rohana AJ, Teoh AN, et al.
    Sex Reprod Healthc, 2019 Jun;20:60-65.
    PMID: 31084820 DOI: 10.1016/j.srhc.2019.03.002
    OBJECTIVES: An optimal gestational weight gain is essential for maternal health and to reduce adverse birth outcomes. Current guidelines to monitor gestational weight gain are based on pre-pregnancy body mass index (BMI). However, middle-upper arm circumference (MUAC) is increasingly used as an alternative nutritional status measure for pregnant women. Hence, this study aimed to determine associations of MUAC and pre-pregnancy BMI with gestational weight gain rate among Malaysian pregnant women.

    STUDY DESIGN: A cross-sectional study was conducted among 444 pregnant women (≥20 weeks gestation).

    MAIN OUTCOMES MEASURES: Women completed questionnaires on sociodemographic data, maternal characteristics and pre-pregnancy weight. Height, current weight and MUAC were measured at study visit (from 1st February 2016 to 31st January 2017).

    RESULTS: About a third (34.24%) of pregnant women were overweight or obese prior to pregnancy. MUAC was inversely associated with an inadequate rate of gestational weight gain (OR = 0.77; 95% CI: 0.68, 0.87) as compared to normal gestational weight gain. In contrast, a higher MUAC was associated with a higher odds ratio (OR = 1.28; 95% CI: 1.11, 1.49) of having excessive rate of gestational weight. No associations were found for pre-pregnancy BMI categories for gestational weight gain rate.

    CONCLUSION: Our findings revealed that women with low MUAC were more likely to have an inadequate gestational weight gain rate during pregnancy whereas higher MUAC was associated with an excessive gestational weight gain rate. MUAC may be a useful indicator of nutritional status associated with GWG. Routine measurement of MUAC in pregnant women may help health professionals, particularly in middle-income countries, to counsel women about gestational weight gain.

  16. Sharifuddin N, Abdul Aziz AF, Sheikh Hamzah M, Abdul Rashid R, Zainuddin Z, Wan Puteh SE, et al.
    Background: Erectile dysfunction (ED) is common amongst hypertensive men. Hypertensive patients often attribute it to antihypertensive drugs, although conflicting evidence linking ED with antihypertensive medication exists. The objectives were to determine the prevalence and severity of ED, the type of treatment sought, and the risk factors for ED among hypertensive men.
    Method: A cross-sectional survey conducted over six months from June to November 2008 at University Kebangsaan, Malaysia Medical Centre, Kuala Lumpur. Inclusion criteria included hypertensive men above 30 years old, with essential hypertension for at least three months. We excluded diabetics, a history of pelvic surgery and known psychiatric illnesses. The International Index of Erectile Function-5 (IIEF-5) assessment was used with a standardised checklist. We analysed data using SPSS, to assess the prevalence and association of ED with selected variables.
    Results: Of the 200 participants screened, 35.5% perceived that they had ED. However, prevalence increased to 69% after screening using an IIEF-5 questionnaire. Forty-eight per cent were reported to have moderate-to severe ED. ED was significantly associated with age (p-value = 0.0001). No significant associations were found between ED and the duration of the hypertension (p-value = 0.505), hypertension control (p-value > 0.05), smoking status (p-value = 0.858) or number of antihypertensive medication taken (p-value > 0.05). Among perceived and proven ED patients, traditional medicines were mainly used for treatment (18.3% and 17.2% respectively).
    Conclusion: ED is a problem among hypertensive patients. It was associated with age but not with hypertension duration, control, number of antihypertensive drugs or smoking. Physicians should enquire about ED symptoms in hypertensive patients, as most of them resorted to self-treatment with traditional medicines. © SAAFP.
  17. Thorlacius L, Garg A, Ingram JR, Villumsen B, Theut Riis P, Gottlieb AB, et al.
    Br J Dermatol, 2018 03;178(3):715-721.
    PMID: 29080368 DOI: 10.1111/bjd.16093
    BACKGROUND: A core outcomes set (COS) is an agreed minimum set of outcomes that should be measured and reported in all clinical trials for a specific condition. Hidradenitis suppurativa (HS) has no agreed-upon COS. A central aspect in the COS development process is to identify a set of candidate outcome domains from a long list of items. Our long list had been developed from patient interviews, a systematic review of the literature and a healthcare professional survey, and initial votes had been cast in two e-Delphi surveys. In this manuscript, we describe two in-person consensus meetings of Delphi participants designed to ensure an inclusive approach to generation of domains from related items.

    OBJECTIVES: To consider which items from a long list of candidate items to exclude and which to cluster into outcome domains.

    METHODS: The study used an international and multistakeholder approach, involving patients, dermatologists, surgeons, the pharmaceutical industry and medical regulators. The study format was a combination of formal presentations, small group work based on nominal group theory and a subsequent online confirmation survey.

    RESULTS: Forty-one individuals from 13 countries and four continents participated. Nine items were excluded and there was consensus to propose seven domains: disease course, physical signs, HS-specific quality of life, satisfaction, symptoms, pain and global assessments.

    CONCLUSIONS: The HISTORIC consensus meetings I and II will be followed by further e-Delphi rounds to finalize the core domain set, building on the work of the in-person consensus meetings.

  18. Choon SE, Khoo JJ
    Br J Dermatol, 1999 Mar;140(3):557-8.
    PMID: 10233296
  19. Goh SE, Ong SB, Subramaniam M
    Br J Psychiatry, 1993 Feb;162:276-7.
    PMID: 8435714
  20. Loo JSE, Lim SW, Ng YK, Tiong JJL
    Int J Pharm Pract, 2017 Dec;25(6):429-437.
    PMID: 28211115 DOI: 10.1111/ijpp.12352
    OBJECTIVES: To identify factors influencing the decisions of Malaysian first-year pharmacy undergraduate students in private higher education when choosing to pursue a degree in pharmacy as well as their choice of private university.

    METHODS: This cross-sectional study employed a validated, self-administered questionnaire which was administered to 543 first-year pharmacy students from nine different private universities. Factor analysis was utilised to extract key factors from the responses. Descriptive and inferential statistics were used to analyse the data.

    KEY FINDINGS: Eight factors motivating students' decision to study pharmacy emerged from the responses, accounting for 63.8% of the variance observed. Students were primarily motivated by intrinsic interests, with work conditions and profession attributes also exerting significant influence. In terms of choice of private university, nine factors were identified, accounting for 73.8% of the variance observed. The image of the school and university were most influential factors in this context, followed by university safety, programme attributes and financial factors.

    CONCLUSIONS: First-year pharmacy students in the private higher education sector are motivated by intrinsic interest when choosing to study pharmacy over other courses, while their choice of private university is influenced primarily by the image of the school and university.

Related Terms
Filters
Contact Us

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

External Links