MyMedR

Displaying all 12 publications

Abstract:

Sort:

Fulltext Acute renal failure in Kuala Lumpur

Suleiman AB, Yahya S

Med J Malaysia, 1981 Mar;36(1):11-3.
PMID: 7321930

One hundred and fifty two patients were treated for acute renal failure in 1976-1978. Overall mortality was 46 (30.3 percent) and was highest among the surgical patients 15 (51.7 percent) and lowest in patients with outflow tract obstruction 2 (8.7 percent) uncontrolled sepsis was the commonest cause of death.
Fulltext Bringing X, Y, Z generations together to facilitate school-based sexual and reproductive health education

Kamrani MA, Syed Yahya S

Glob J Health Sci, 2016;8(9):54741.
PMID: 27157180 DOI: 10.5539/gjhs.v8n9p132

This generic qualitative study explores the perspective of Malaysian teachers regarding the constraints of the current school-based sexual and reproductive health education in secondary schools of Klang-Valley Malaysia. For this study, in-depth interviews were conducted with twenty eight science teachers of government schools. The majority of participants named the teaching strategy and capacity of teachers, the lack of co-operation from the school and parents, limited resources in teaching and students themselves as some of the challenges. We concluded that if sexual health education is to be effective, it needs to be provided by people who have some specialized training. The teachers should be trained to teach sexual reproductive health education classes at the basic level, and in-service training for teachers already in the field should be intensified. Local adaptation to culture, language, religion, and so forth is often necessary.
Validation of the Malay version of the Modified Dental Anxiety Scale and the prevalence of dental anxiety in a Malaysian population

Sitheeque M, Massoud M, Yahya S, Humphris G

J Investig Clin Dent, 2015 Nov;6(4):313-20.
PMID: 25045162 DOI: 10.1111/jicd.12106

The aims of the present study were to evaluate the reliability and validity of the Malay version of the Modified Dental Anxiety Scale (MDAS), and to determine the prevalence of dental anxiety and associated factors in a Malaysian population.
Fulltext Joint torque reduction of a three dimensional redundant planar manipulator

Yahya S, Moghavvemi M, Almurib HA

Sensors (Basel), 2012;12(6):6869-92.
PMID: 22969326 DOI: 10.3390/s120606869

Research on joint torque reduction in robot manipulators has received considerable attention in recent years. Minimizing the computational complexity of torque optimization and the ability to calculate the magnitude of the joint torque accurately will result in a safe operation without overloading the joint actuators. This paper presents a mechanical design for a three dimensional planar redundant manipulator with the advantage of the reduction in the number of motors needed to control the joint angle, leading to a decrease in the weight of the manipulator. Many efforts have been focused on decreasing the weight of manipulators, such as using lightweight joints design or setting the actuators at the base of the manipulator and using tendons for the transmission of power to these joints. By using the design of this paper, only three motors are needed to control any n degrees of freedom in a three dimensional planar redundant manipulator instead of n motors. Therefore this design is very effective to decrease the weight of the manipulator as well as the number of motors needed to control the manipulator. In this paper, the torque of all the joints are calculated for the proposed manipulator (with three motors) and the conventional three dimensional planar manipulator (with one motor for each degree of freedom) to show the effectiveness of the proposed manipulator for decreasing the weight of the manipulator and minimizing driving joint torques.
Fulltext WS2: A New Window Layer Material for Solar Cell Application

Bin Rafiq MKS, Amin N, Alharbi HF, Luqman M, Ayob A, Alharthi YS, et al.

Sci Rep, 2020 Jan 21;10(1):771.
PMID: 31964954 DOI: 10.1038/s41598-020-57596-5

Radio frequency (RF) magnetron sputtering was used to deposit tungsten disulfide (WS2) thin films on top of soda lime glass substrates. The deposition power of RF magnetron sputtering varied at 50, 100, 150, 200, and 250 W to investigate the impact on film characteristics and determine the optimized conditions for suitable application in thin-film solar cells. Morphological, structural, and opto-electronic properties of as-grown films were investigated and analyzed for different deposition powers. All the WS2 films exhibited granular morphology and consisted of a rhombohedral phase with a strong preferential orientation toward the (101) crystal plane. Polycrystalline ultra-thin WS2 films with bandgap of 2.2 eV, carrier concentration of 1.01 × 1019 cm-3, and resistivity of 0.135 Ω-cm were successfully achieved at RF deposition power of 200 W. The optimized WS2 thin film was successfully incorporated as a window layer for the first time in CdTe/WS2 solar cell. Initial investigations revealed that the newly incorporated WS2 window layer in CdTe solar cell demonstrated photovoltaic conversion efficiency of 1.2% with Voc of 379 mV, Jsc of 11.5 mA/cm2, and FF of 27.1%. This study paves the way for WS2 thin film as a potential window layer to be used in thin-film solar cells.
Fulltext A multi-modal approach to investigate Desmodium gangeticum's influence on stress-induced male infertility: In vivo, in vitro, and in silico assessments

Alqahtani YS, Chidrawar VR, Shiromwar S, Singh S, Maheshwari R, Chitme H, et al.

Biomed Pharmacother, 2024 Apr;173:116358.
PMID: 38430634 DOI: 10.1016/j.biopha.2024.116358

Physical and psychological stress has an inverse relation with male libido and sperm quality. The present study investigates the potential fertility-enhancing properties of Desmodium gangeticum (DG) root extracts in male Wister rats subjected to immobilization-induced stress (SIMB). DG roots were extracted using n-hexane (HEDG), chloroform (CEDG), and water (AEDG). In the pilot study, aphrodisiac protentional was investigated at two doses (125 and 250 mg kg-1) of each extract. In the main study, the HEDG and AEDG at 125 and 250 mg kg-1 were challenged for the stress by immobilization (SIMB), for 6 h daily over 28 days. Parameters assessed included aphrodisiac effects, gonadosomatic index (GSI), semen quality, sperm quantity, fructose content, serum hormonal levels, testicular oxidative stress, and testicular histopathology. Additional in silico studies, including the lipid solubility index, molecular docking, molecular dynamics, and SymMap studies were conducted for validation. HEDG demonstrated significant aphrodisiac activity, improved - GSI, sperm quality and quantity, and fructose content, serum testosterone levels, histological changes induced by SIMB in the testes. Swiss ADME studies indicated Gangetin (a pterocarpan) had a high brain permeation index (4.81), a superior docking score (-8.22), and higher glide energy (-42.60), compared with tadalafil (-7.17). The 'Lig fit Prot' plot in molecular dynamics simulations revealed a strong alignment between Gangetin and phosphodiesterase type 5 (PDE5). HEDG exerts aphrodisiac effects by increasing blood testosterone levels and affecting PDE5 activity. The protective effects on spermatozoa-related parameters and testicular histological changes are attributed to the antioxidant and anti-inflammatory properties, of pterocarpan (gangetin).
Fulltext Barriers of modern contraceptive practices among Asian women: a mini literature review

Najafi-Sharjabad F, Zainiyah Syed Yahya S, Abdul Rahman H, Hanafiah Juni M, Abdul Manaf R

Glob J Health Sci, 2013 Sep;5(5):181-92.
PMID: 23985120 DOI: 10.5539/gjhs.v5n5p181

Family planning has been cited as essential to the achievement of Millennium Development Goals (MDG). Family planning has a direct impact on women's health and consequence of each pregnancy. The use of modern contraception among Asian women is less than global average. In Asia a majority of unintended pregnancies are due to using traditional contraceptive or no methods which lead to induced unsafe abortion. Cultural attitudes, lack of knowledge of methods and reproduction, socio demographic factors, and health service barriers are the main obstacles to modern contraceptive practice among Asian women. Culturally sensitive family planning program, reforming health system, and reproductive health education through mass media to create awareness of the benefits of planned parenthood are effective strategies to improve modern contraceptive practice among Asian women.
Fulltext Experimental and Theoretical Studies on Extract of Date Palm Seed as a Green Anti-Corrosion Agent in Hydrochloric Acid Solution

Mohammed NJ, Othman NK, Taib MFM, Samat MH, Yahya S

Molecules, 2021 Jun 09;26(12).
PMID: 34207914 DOI: 10.3390/molecules26123535

Extracts from plant materials have great potential as alternatives to inorganic corrosion inhibitors, which typically have harmful consequences. Experimental and theoretical methodologies studied the effectiveness of agricultural waste, namely, date palm seed extract as a green anti-corrosive agent in 0.5 M hydrochloric acid. Experimental results showed that immersion time and temperature are closely related to the effectivity of date palm seed as a corrosion inhibitor. The inhibition efficiency reduced from 95% to 91% at 1400 ppm when the immersion time was increased from 72 h to 168 h. The experimental results also indicated that the inhibition efficiency decreased as the temperature increased. The presence of a protective layer of organic matter was corroborated by scanning electron microscopy. The adsorption studies indicated that date palm seed obeyed Langmuir adsorption isotherm on the carbon steel surface, and Gibbs free energy values were in the range of -33.45 to -38.41 kJ·mol-1. These results suggested that the date palm seed molecules interacted with the carbon steel surface through mixture adsorption. Theoretical calculations using density functional theory showed that the capability to donate and accept electrons between the alloy surface and the date palm seed inhibitor molecules is critical for adsorption effectiveness. The HOMO and LUMO result indicated that the carboxyl (COOH) group and C=C bond were the most active sites for the electron donation-acceptance type of interaction and most auxiliary to the adsorption process over the Fe surface.
Patient-Specific Reconstruction Utilizing Computer Assisted 3D Modelling for Partial Bone Flap Defect in Hybrid Cranioplasty

Low PH, Abdullah JY, Abdullah AM, Yahya S, Idris Z, Mohamad D

J Craniofac Surg, 2019 Jun 28.
PMID: 31261343 DOI: 10.1097/SCS.0000000000005713

PURPOSE: Decompressive craniectomy is a life-saving procedure in the setting of malignant brain swelling. Patients who survive require cranioplasty for anatomical reconstruction and cerebral protection. Autologous cranioplasty remains the commonest practice nowadays, but partial bone flap defects are frequently encountered. The authors, therefore, seek to develop a new technique of reconstruction for cranioplasty candidate with partial bone flap defect utilizing computer-assisted 3D modeling and printing.
METHODS: A prospective study was conducted to evaluate the outcome of a new reconstruction technique that produces patient-specific hybrid polymethyl methacrylate-autologous cranial implant. Computer-assisted 3D modeling and printing was utilized to produce patient-specific molds, which allowed real-time reconstruction of bone flap with partial defect intra-operatively.
RESULTS: Outcome assessment for 11 patients at 6 weeks and 3 months post-operatively revealed satisfactory implant alignment with favorable cosmesis. The mean visual analog scale for cosmesis was 91. Mean implant size was 50cm, and the mean duration of intra-operative reconstruction was 30 minutes. All of them revealed improvement in quality of life following surgery as measured by the SF-36 score. Cost analysis revealed that this technique is more cost-effective compared to customized cranial prosthesis.
CONCLUSION: This new technique and approach produce hybrid autologous-alloplastic bone flap that resulted in satisfactory implant alignment and favorable cosmetic outcome with relatively low costs.
Fulltext A new compact and low phase imbalance microstrip coupler for 5G wireless communication systems

I Yahya S, Zubir F, Nouri L, Yusoff Z, Chaudhary MA, Assaad M, et al.

PLoS One, 2023;18(12):e0296272.
PMID: 38134045 DOI: 10.1371/journal.pone.0296272

Microstrip couplers play a crucial role in signal processing and transmission in various applications, including RF and wireless communication, radar systems, and satellites. In this work, a novel microstrip 180° coupler is designed, fabricated and measured. The layout configuration of this coupler is completely new and different from the previously reported Rat-race, branch-line and directional couplers. To obtain the proposed coupler, the meandrous coupled lines are used and analyzed mathematically. To improve the performance of our coupler, an optimization method is used. The designed coupler is very compact with an overall size of 0.014λg2. The obtained values of S21 and S31 are -3.45 dB and -3.75 dB, respectively at the operating frequency, while the fractional bandwidth (FBW) is 56.2%. It operates at fo = 1.61 GHz (suitable for 5G applications) and can suppress harmonics up to 2.17fo. Another advantage of this coupler is its low phase imbalance, while the phase difference between S21 and S31 is 180°± 0.023°. Therefore, our device is a balanced coupler with ±0.3 dB magnitude unbalance at its operating frequency. It is important to note that it is very difficult to find a coupler that has all these advantages at the same time. The proposed 180° coupler is fabricated and measured. The comparison shows that the measurement and simulation results are in good agreement. Therefore, the proposed coupler can be easily used in designing high-performance 5G communication systems.
Fulltext Evaluation of reference genes for quantitative real-time PCR in oil palm elite planting materials propagated by tissue culture

Chan PL, Rose RJ, Abdul Murad AM, Zainal Z, Low ET, Ooi LC, et al.

PLoS One, 2014;9(6):e99774.
PMID: 24927412 DOI: 10.1371/journal.pone.0099774

The somatic embryogenesis tissue culture process has been utilized to propagate high yielding oil palm. Due to the low callogenesis and embryogenesis rates, molecular studies were initiated to identify genes regulating the process, and their expression levels are usually quantified using reverse transcription quantitative real-time PCR (RT-qPCR). With the recent release of oil palm genome sequences, it is crucial to establish a proper strategy for gene analysis using RT-qPCR. Selection of the most suitable reference genes should be performed for accurate quantification of gene expression levels.
Early nodulin 93 protein gene: essential for induction of somatic embryogenesis in oil palm

Chan PL, Rose RJ, Abdul Murad AM, Zainal Z, Ong PW, Ooi LC, et al.

Plant Cell Rep, 2020 Nov;39(11):1395-1413.
PMID: 32734510 DOI: 10.1007/s00299-020-02571-7

KEY MESSAGE: Transcript profiling during the early induction phase of oil palm tissue culture and RNAi studies in a model somatic embryogenesis system showed that EgENOD93 expression is essential for somatic embryogenesis. Micropropagation of oil palm through tissue culture is vital for the generation of superior and uniform elite planting materials. Studies were carried out to identify genes to distinguish between leaf explants with the potential to develop into embryogenic or non-embryogenic callus. Oil palm cDNA microarrays were co-hybridized with cDNA probes of reference tissue, separately with embryo forming (media T527) and non-embryo (media T694) forming leaf explants sampled at Day 7, Day 14 and Day 21. Analysis of the normalized datasets has identified 77, 115 and 127 significantly differentially expressed genes at Day 7, Day 14, and Day 21, respectively. An early nodulin 93 protein gene (ENOD93), was highly expressed at Day 7, Day 14, and Day 21 and in callus (media T527), as assessed by RT-qPCR. Validation of EgENOD93 across tissue culture lines of different genetic background and media composition showed the potential of this gene as an embryogenic marker. In situ RNA hybridization and functional characterization in Medicago truncatula provided additional evidence that ENOD93 is essential for somatic embryogenesis. This study supports the suitability of EgENOD93 as a marker to predict the potential of leaf explants to produce embryogenic callus. Crosstalk among stresses, auxin, and Nod-factor like signalling molecules likely induces the expression of EgENOD93 for embryogenic callus formation.

Filters

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

External Links