Displaying publications 141 - 160 of 220 in total

Abstract:
Sort:
  1. Leong OS, Ghazali S, Hussin EOD, Lam SK, Japar S, Geok SK, et al.
    Br J Community Nurs, 2020 Feb 02;25(2):84-90.
    PMID: 32040358 DOI: 10.12968/bjcn.2020.25.2.84
    With the older population increasing worldwide, depressive disorder in this cohort is a serious public health problem that contributes to increased healthcare costs and mortality. This study aimed to determine the prevalence of depression among older adults in Malaysia who attended a daycare centre and to identify the relationship between depression and demographic factors. A cross-sectional study was conducted with 159 older adults recruited following screening for mental capacity. The Malay Geriatric Depression Scale questionnaire was distributed among the participants to obtain descriptive data on the symptoms of depression. Some 59.1% of the participants experienced depression. The most common factors associated with depression were being divorced, low education levels and low income. The findings indicate the need to revise and re-evaluate the activities and programmes in daycare centres for older adults in order to objectively cater to their physical and emotional needs.
  2. Thari FZ, Tachallait H, El Alaoui NE, Talha A, Arshad S, Álvarez E, et al.
    Ultrason Sonochem, 2020 Nov;68:105222.
    PMID: 32585575 DOI: 10.1016/j.ultsonch.2020.105222
    A rapid and green method for the synthesis of novel N-thiazolidine-2,4-dione isoxazoline derivatives 5 from N-allyl-5-arylidenethiazolidine-2,4-diones 3 as dipolarophiles with arylnitrile oxides via 1,3-dipolar cycloaddition reaction. The corresponding N-allyl substituted dipolarophiles were prepared by one-pot method from thiazolidine-2,4-dione with aldehydes using Knoevenagel condensation followed by N-allylation of thiazolidine-2,4-dione in NaOH aqueous solution under sonication. In addition, the isoxazoline derivatives 5 were synthesized by regioselective and chemoselective 1,3-dipolar cycloaddition using inexpensive and mild NaCl/Oxone/Na3PO4 as a Cl source, oxidant and/or catalyst under ultrasonic irradiation in EtOH/H2O (v/v, 2:1) as green solvent. All synthesized products are furnished in good yields in the short reaction time, and then their structures were confirmed by NMR, mass spectrometry and X-ray crystallography analysis.
  3. Yahya NFS, Daud NM, Makbul IAA, Aziz QASA
    Arch Osteoporos, 2021 01 15;16(1):14.
    PMID: 33452644 DOI: 10.1007/s11657-020-00874-6
    Lactose intolerance has been proposed to cause poor bone health. This study found the prevalence of lactose intolerance was high among Malaysian young adults, but not associated with bone health status, unlike calcium intake. This is the first study that investigated the association of lactose intolerance and bone health status in Malaysia.

    PURPOSE: The aims of this study were to determine the prevalence of lactose intolerance, calcium intake and physical activity level and to investigate the association between these variables with bone health status among young adults.

    METHODS: This cross-sectional study consisted of 300 Malay, Chinese and Indian students from Universiti Kebangsaan Malaysia with mean age of 22.5 ± 3.2 years. Determination of lactose tolerance status was performed using hydrogen breath test, lactose tolerance test and visual analogue scales. Calcium intake and physical activity level were evaluated using Food Frequency Questionnaire and International Physical Activity Questionnaire, respectively. Bone health status was assessed on calcaneal bone, using quantitative ultrasound.

    RESULTS: Lactose intolerance was highly reported among the Malay subjects (72%) followed by Chinese (59%) and Indians (42%). The mean calcium intake was 542.9 ± 365.2 mg/day whilst the mean physical activity was 2757.6 ± 2007.2 MET-min/week. The bone assessment showed that 91% of the subjects had a low risk of developing osteoporosis. Only calcium intake showed a significant association with bone health status (β = 0.006; p = 0.033), whilst no association was shown for lactose intolerance and physical activity level.

    CONCLUSIONS: Malaysian young adults showed a high prevalence of lactose intolerance. Calcium intake is associated with increased bone health status. In contrast, lactose intolerance and physical activity level did not directly influence bone health status. Nutrition education promoting adequate calcium intake should be implemented among young adults due to high lactose intolerance prevalence and low calcium intake among subjects.

  4. Zainuri DA, Abdullah M, Zaini MF, Bakhtiar H, Arshad S, Abdul Razak I
    PLoS One, 2021;16(9):e0257808.
    PMID: 34582495 DOI: 10.1371/journal.pone.0257808
    The Ultraviolet-visible (UV-Vis) spectra indicate that anthracenyl chalcones (ACs) have high maximum wavelengths and good transparency windows for optical applications and are suitable for optoelectronic applications owing to their HOMO-LUMO energy gaps (2.93 and 2.76 eV). Different donor substituents on the AC affect their dipole moments and nonlinear optical (NLO) responses. The positive, negative, and neutral electrostatic potential regions of the molecules were identified using molecular electrostatic potential (MEP). The stability of the molecule on account of hyperconjugative interactions and accompanying charge delocalization was analyzed using natural bond orbital (NBO) analysis. Open and closed aperture Z-scans were performed using a continuous-wave frequency-doubled diode-pumped solid-state (DPSS) laser to measure the nonlinear absorption and nonlinear refractive index coefficients, respectively. The valley-to-peak profile of AC indicated a negative nonlinear refractive index coefficient. The obtained single crystals possess reverse saturation absorption due to excited-state absorption. The structural and nonlinear optical properties of the molecules have been discussed, along with the role of anthracene substitution for enhancing the nonlinear optical properties. The calculated third-order susceptibility value was 1.10 x10-4 esu at an intensity of 4.1 kW/cm2, higher than the reported values for related chalcone derivatives. The NLO response for both ACs offers excellent potential in optical switching and limiting applications.
  5. Rahman MNA, Zubir NSM, Leuveano RAC, Ghani JA, Mahmood WMFW
    Materials (Basel), 2014 Dec 02;7(12):7706-7721.
    PMID: 28788270 DOI: 10.3390/ma7127706
    The significant increase in metal costs has forced the electronics industry to provide new materials and methods to reduce costs, while maintaining customers' high-quality expectations. This paper considers the problem of most electronic industries in reducing costly materials, by introducing a solder paste with alloy composition tin 98.3%, silver 0.3%, and copper 0.7%, used for the construction of the surface mount fine-pitch component on a Printing Wiring Board (PWB). The reliability of the solder joint between electronic components and PWB is evaluated through the dynamic characteristic test, thermal shock test, and Taguchi method after the printing process. After experimenting with the dynamic characteristic test and thermal shock test with 20 boards, the solder paste was still able to provide a high-quality solder joint. In particular, the Taguchi method is used to determine the optimal control parameters and noise factors of the Solder Printer (SP) machine, that affects solder volume and solder height. The control parameters include table separation distance, squeegee speed, squeegee pressure, and table speed of the SP machine. The result shows that the most significant parameter for the solder volume is squeegee pressure (2.0 mm), and the solder height is the table speed of the SP machine (2.5 mm/s).
  6. Zahid NI, Mahmood MS, Subramanian B, Mohd Said S, Abou-Zied OK
    J Phys Chem Lett, 2017 Nov 16;8(22):5603-5608.
    PMID: 29094952 DOI: 10.1021/acs.jpclett.7b02601
    Fluorescence upconversion and transient absorption techniques are used to explain the source of the intense red/near-infrared emission of crystalline 4-dimethylamino-2'-hydroxychalcone. We found that the initially excited enol form undergoes tautomerization in 3 ps to form the keto tautomer. The latter is stable in the ground state as a consequence of J-type aggregation in the crystal packing and is manifested in an absorption peak at 550 nm that spectrally overlaps with the short-lived enol emission, leading to self-reabsorption and adding a factor to the complete depletion of the enol emission. Relaxation of the keto tautomer takes place in the form of intense fluorescence (600-750 nm) with 1.7 ns lifetime. The different spectroscopy in solution is due to vibrational cooling (300 fs), followed by solvation dynamics (5 ps in methanol) and twisting of the hydroxyphenyl ring (16 ps), before relaxation of the enol tautomer in the form of weak green fluorescence with 350 ps lifetime.
  7. Shahriman MS, Ramachandran MR, Zain NNM, Mohamad S, Manan NSA, Yaman SM
    Talanta, 2018 Feb 01;178:211-221.
    PMID: 29136814 DOI: 10.1016/j.talanta.2017.09.023
    In this present study, magnetic nanoparticles (MNPs) nanocomposites modified with polyaniline (PANI) coated newly synthesised dicationic ionic liquid (DICAT) forming MNP-PANI-DICAT were successfully synthesised as new generation material for magnetic solid phase extraction (MSPE). MNP-PANI-DICAT was characterised by FT-IR NMR, CHN, BET, SEM, TEM, and VSM techniques and the results were compared with MNP-PANI and native MNP. This new material was applied as a magnetic adsorbent for the pre-concentration and separation of polycyclic aromatic hydrocarbons (PAHs) due to the π-π interaction between polyaniline shell and dicationic ionic liquid (DICAT) with PAHs compounds. Under the optimal conditions, the proposed method was evaluated and applied for the analysis of PAHs in environmental samples using gas chromatography-mass spectrometry (GC-MS). The validation method showed good linearity (0.005-500µgL-1) with the coefficient of determination (R2) > 0.999. The limits of detection (LOD) and quantification (LOQ) of the developed method (MNP-PANI-DICAT-MSPE) were in the range of 0.0008-0.2086µgL-1and 0.0024-0.6320µgL-1, respectively. The enrichment factor (EF) of PAHs on MNP-PANI-DICAT-MSPE were in the range of 7.546-29.632. The extraction recoveries of natural water, sludge, and soil samples were ranged from 80.2% to 111.9% with relative standard deviation (RSD) less than 5.6%. The newly synthesised MNP-PANI-DICAT possess good sensitivity, reusability, and fast extraction of PAHs under the MSPE procedure in various environmental samples.
  8. Kamarudin TA, Othman F, Mohd Ramli ES, Md Isa N, Das S
    EXCLI J, 2012;11:226-36.
    PMID: 27366139
    Curcuma longa (turmeric) rhizomes contains curcumin, an active compound which possesses anti-inflammatory effects. Collagen-induced arthritis (CIA) is an accepted experimental animal model of rheumatoid arthritis. The present study aimed to observe the histological changes in the joints of experimental arthritic rats treated with curcumin. Twenty four male Sprague-Dawley (approximately 7 weeks-old) rats were randomly divided into four groups. Three groups were immunized with 150 µg collagen. All rats with established CIA, with arthritis scores exceeding 1, were orally treated with betamethasone (0.5 mg/ml/kg body weight), curcumin (110 mg/ml/kg body weight) or olive oil (1.0 ml/kg body weight) daily, for two weeks. One remaining group was kept as normal control. Treatment with 110 mg/ml/kg curcumin showed significant mean differences in the average white blood cell (WBC) count (p<0.05), cell infiltration, bone and cartilage erosion scores (p<0.05) compared to the olive oil treated group. Pannus formation scores showed that curcumin supplementation successfully suppressed the pannus formation process that occurred in the articular cartilage of the CIA joints. The mean difference for histological scores for the curcumin group was insignificant compared to the betamethasone treated group. It is concluded that supplementation of curcumin has protective effect on the histopathological and degenerative changes in the joints of CIA rats which was at par with betamethasone.
  9. Tajul Arifin K, Sulaiman S, Md Saad S, Ahmad Damanhuri H, Wan Ngah WZ, Mohd Yusof YA
    BMC Cancer, 2017 12 21;17(1):879.
    PMID: 29268718 DOI: 10.1186/s12885-017-3883-3
    BACKGROUND: Chlorella vulgaris (ChV), a unicellular green algae has been reported to have anticancer and antioxidant effects. The aim of this study was to determine the chemopreventive effect of ChV on liver cancer induced rats by determining the level and expression of several liver tumour markers.

    METHODS: Male Wistar rats (200-250 g) were divided into 4 groups according to the diet given: control group (normal diet), ChV group with three different doses (50, 150 and 300 mg/kg body weight), liver cancer- induced group (choline deficient diet + 0.1% ethionine in drinking water or CDE group), and the treatment group (CDE group treated with three different doses of ChV). Rats were killed at 0, 4, 8 and 12 weeks of experiment and blood and tissue samples were taken from all groups for the determination of tumour markers expression alpha-fetoprotein (AFP), transforming growth factor-β (TGF-β), M2-pyruvate kinase (M2-PK) and specific antigen for oval cells (OV-6).

    RESULTS: Serum level of TGF-β increased significantly (p < 0.05) in CDE rats. However, ChV at all doses managed to decrease (p < 0.05) its levels to control values. Expressions of liver tumour markers AFP, TGF-β, M2-PK and OV-6 were significantly higher (p < 0.05) in tissues of CDE rats when compared to control showing an increased number of cancer cells during hepatocarcinogenesis. ChV at all doses reduced their expressions significantly (p < 0.05).

    CONCLUSIONS: Chlorella vulgaris has chemopreventive effect by downregulating the expression of tumour markers M2-PK, OV-6, AFP and TGF-β, in HCC-induced rats.

  10. Ahmad S, Hatmal MM, Lambuk L, Al-Hatamleh MAI, Alshaer W, Mohamud R
    Life Sci, 2021 Dec 01;286:120063.
    PMID: 34673116 DOI: 10.1016/j.lfs.2021.120063
    COVID-19 is a multi-faceted disease ranging from asymptomatic to severely ill condition that primarily affects the lungs and could advance to other organs as well. It's causing factor, SARS-CoV-2 is recognized to develop robust cell-mediated immunity that responsible to either control or exaggerate the infection. As an important cell subset that control immune responses and are significantly dysregulated in COVID-19, Tregs is proposed to be considered for COVID-19 management. Among its hallmark, TNFR2 is recently recognized to play important role in the function and survival of Tregs. This review gathers available TNFR2 agonists to directly target Tregs as a potential approach to overcome immune dysregulation that affect the severity in COVID-19. Furthermore, this review performs a rigid body docking of TNF-TNFR2 interaction and such interaction with TNFR2 agonist to predict the optimal targeting approach.
  11. Balqis-Ali NZ, Jailani AS, Fun WH, Jawahir S, Sararaks S, Lee GHY
    Heliyon, 2023 Mar;9(3):e14025.
    PMID: 36879958 DOI: 10.1016/j.heliyon.2023.e14025
    Supplementary private health insurance (PHI) provides better access to healthcare, improves health outcomes, potentially lowers the costs for health systems and supports the social security system. Improperly regulated PHI, however, may aggravate inequity of access towards preferential care and encourage moral hazard among PHI purchasers, altering the health-seeking behaviour, which is often observed through the pattern of health care utilisation. We investigated the effect of PHI ownership on private inpatient care utilisation, its frequency of admission and length of stay by conducting secondary data analysis of the Malaysian National Health Morbidity Survey (NHMS) 2015 data, a nationally representative community health survey. Malaysian adults 18 years of age and above who utilised inpatient healthcare facilities were included. In this cross-sectional study, we addressed the endogeneity effect of health insurance by employing instrumental variable estimation and a two-stage residual inclusion analysis. We found a significant increase in private inpatient utilisation among those who owned PHI compared to those who did not (β = 4.39, p 
  12. Yeo JS, Koting S, Onn CC, Radwan MKH, Cheah CB, Mo KH
    PMID: 36988805 DOI: 10.1007/s11356-023-26496-2
    This research incorporates sustainable materials such as ground granulated blast furnace slag (GGBS) and recycled waste glass (RWG) as cement and fine aggregate replacement respectively to produce green dry mix mortar paving blocks. The GGBS and RWG contents in the mortar paving block were optimised using the response surface methodology (RSM), considering the performances of the ultrasonic pulse velocity (UPV), flexural and compressive strengths, water absorption, and Cantabro loss. Life cycle assessment (LCA) was also conducted to evaluate the environmental impact of the optimised green mortar paving blocks. The RSM suggested that the paving block with optimum GGBS and RWG contents of 26.5% and 91.3%, respectively, could exhibit compressive strength of 36.5 MPa, which complied with the requirement for concrete segmental paving units (MA20). Excluding the mixes not fulfilling the MA20 requirement, the mix with 40% GGBS and 100% RWG exhibited the lowest values for the acidification potential (AP), global warming potential (GWP), photochemical oxidation (POCP), abiotic depletion potential for fossil fuel (ADPF), and water scarcity/strength ratio. Whereas, for eutrophication potential (EP) and abiotic depletion for elements (ADP (elements))/strength ratio, the mix with 100% RWG exhibited the lowest value. The optimised mix from RSM showed a similar performance as the two mixes.
  13. Ishak MAI, Aun TT, Sidek N, Mohamad S, Jumbri K, Abdul Manan NS
    J Comput Chem, 2024 Jun 15;45(16):1329-1351.
    PMID: 38372509 DOI: 10.1002/jcc.27321
    In this study, the enantioselectivity of β-cyclodextrin and its derivatives towards propranolol enantiomers are investigated by molecular dynamic (MD) simulations. β-cyclodextrin (β-CD) have previously been shown to be able to recognize propranolol (PRP) enantiomers. To improve upon the enantioselectivity of β-cyclodextrin, we propose the use of an ionic-liquid-modified-β-cyclodextrin (β-CD-IL). β-CD-IL was found to be able to complex R and S propranolol enantiomers with differing binding energies. The molecular docking study reveals that the ionic liquid chain attached to the β-CD molecule has significant interaction with propranolol. The formation of the most stable complex occurred between (S)-β-CD-IL and (S)-propranolol with an energy of -5.80 kcal/mol. This is attributed to the formation of a hydrogen bond between the oxygen of the propranolol and the hydrogen on the primary rim of the (S)-β-CD-IL cavity. This interaction is not detected in other complexes. The root mean-squared fluctuation (RMSF) value indicates that the NH group is the most flexible molecular fragment, followed by the aromatic group. Also of note, the formation of a complex between pristine β-CD and (S)-propranolol is the least favorable.
  14. Anizaim AH, Zaini MF, Laruna MA, Razak IA, Arshad S
    Acta Crystallogr E Crystallogr Commun, 2019 May 01;75(Pt 5):632-637.
    PMID: 31110801 DOI: 10.1107/S2056989019004912
    In the title compound, C18H12O3S2, synthesized by the Claisen-Schmidt condensation method, the essentially planar chalcone unit adopts an s-cis configuration with respect to the carbonyl group within the ethyl-enic bridge. In the crystal, weak C-H⋯π inter-actions connect the mol-ecules into zigzag chains along the b-axis direction. The mol-ecular structure was optimized geometrically using Density Functional Theory (DFT) calculations at the B3LYP/6-311 G++(d,p) basis set level and compared with the experimental values. Mol-ecular orbital calculations providing electron-density plots of HOMO and LUMO mol-ecular orbitals and mol-ecular electrostatic potentials (MEP) were also computed both with the DFT/B3LYP/6-311 G++(d,p) basis set. The experimental energy gap is 3.18 eV, whereas the theoretical HOMO-LUMO energy gap value is 2.73 eV. Hirshfeld surface analysis was used to further investigate the weak inter-actions present.
  15. Bouzian Y, Karrouchi K, Anouar EH, Bouhfid R, Arshad S, Essassi EM
    Acta Crystallogr E Crystallogr Commun, 2019 Jun 01;75(Pt 6):912-916.
    PMID: 31391993 DOI: 10.1107/S2056989019007473
    In the title quinoline derivative, C14H14ClNO3, there is an intra-molecular C-H⋯O hydrogen bond forming an S(6) graph-set motif. The mol-ecule is essentially planar with the mean plane of the ethyl acetate group making a dihedral angle of 5.02 (3)° with the ethyl 6-chloro-2-eth-oxy-quinoline mean plane. In the crystal, offset π-π inter-actions with a centroid-to-centroid distance of 3.4731 (14) Å link inversion-related mol-ecules into columns along the c-axis direction. Hirshfeld surface analysis indicates that H⋯H contacts make the largest contribution (50.8%) to the Hirshfeld surface.
  16. Abd Aziz NA, Awang N, Kamaludin NF, Anuar NNM, Hamid A, Chan KM, et al.
    Anticancer Agents Med Chem, 2024;24(12):942-953.
    PMID: 38629375 DOI: 10.2174/0118715206309421240402093335
    BACKGROUND: Organotin(IV) complexes of dithiocarbamate are vital in medicinal chemistry, exhibiting potential in targeting cancer cells due to their unique properties that enhance targeted delivery. This study aimed to synthesize and characterize organotin(IV) N-ethyl-N-benzyldithiocarbamate complexes (ONBDCs) and evaluate their cytotoxicity against A549 cells, which are commonly used as a model for human lung cancer research.

    METHODS: The two ONBDC derivatives - ONBDC 1 (dimethyltin(IV) N-ethyl-N-benzyldithiocarbamate) and ONBDC 2 (triphenyltin(IV) N-ethyl-N-benzyldithiocarbamate) - were synthesized via the reaction of tin(IV) chloride with N-ethylbenzylamine in the presence of carbon disulfide. A range of analytical techniques, including elemental analysis, IR spectroscopy, NMR spectroscopy, UV-Vis spectrometry, TGA/DTA analysis, and X-ray crystallography, was conducted to characterize these compounds comprehensively. The cytotoxic effects of ONBDCs against A549 cells were evaluated using MTT assay.

    RESULTS: Both compounds were synthesized and characterized successfully via elemental and spectroscopies analysis. MTT assay revealed that ONBDC 2 demonstrated remarkable cytotoxicity towards A549 cells, with an IC50 value of 0.52 μM. Additionally, ONBDC 2 displayed significantly higher cytotoxic activity against the A549 cell line when compared to the commercially available chemotherapeutic agent cisplatin (IC50: 32 μM).

    CONCLUSION: Thus, it was shown that ONBDC 2 could have important anticancer properties and should be further explored as a top contender for creating improved and specialized cancer treatments.

  17. El Mahmoudi A, Fegrouche R, Tachallait H, Lumaret JP, Arshad S, Karrouchi K, et al.
    Pest Manag Sci, 2023 Dec;79(12):4847-4857.
    PMID: 37500586 DOI: 10.1002/ps.7686
    BACKGROUND: Sphodroxia maroccana Ley is a pest of cork oak crops that damages the roots of seedlings and can severely impair cork oak regeneration. Since the banning of carbosulfan and chlorpyriphos, which were widely used against the larvae of Sphodroxia maroccana because of their harmful impact on the environment, until now there has been no pesticide against these pests. Therefore, it is particularly urgent to develop highly effective insecticidal molecules with novel scaffolds. Isoxazolines are a class of insecticides that act on γ-aminobutyric acid (GABA)-gated chloride channel allosteric modulators. In this work, a green synthesis of novel 3,5-disubstituted isoxazoline-sulfonamide derivatives was achieved in water via ultrasound-assisted four-component reactions, and their insecticidal activities against fourth-instar larvae of S. maroccana were evaluated.

    RESULTS: Most of the tested compounds showed insecticidal activity compared to fluralaner as positive control and commercially available insecticide. Especially, the isoxazoline-secondary sulfonamides containing halogens (Br and Cl) on the phenyl group attached to the isoxazoline, 6g (LC50  = 0.31 mg/mL), 6j (LC50  = 0.38 mg/mL), 6k (LC50  = 0.18 mg/mL), 6L (LC50  = 0.49 mg/mL), 6m (LC50  = 0.24 mg/mL), 6q (LC50  = 0.46 mg/mL), exhibited much higher larvicidal activity than fluralaner (LC50  = 0.99 mg/mL).

    CONCLUSION: Novel isoxazolines containing sulfonamide moieties were designed, synthesized and confirmed by two single-crystal structures of 4e and 6q. Their bioassay results showed significant larvicidal activity with significant morphological changes in vivo. These results will lay the foundation for the further discovery and development of isoxazoline-sulfonamide derivatives as novel crop protection larvicides of cork oak. © 2023 Society of Chemical Industry.

  18. Zulkifli N'A, Zahir NH, Abdullah Ripain AH, Said SM, Zakaria R
    Nanoscale Adv, 2023 Jan 31;5(3):879-892.
    PMID: 36756501 DOI: 10.1039/d2na00756h
    Molybdenum disulfide (MoS2) has been attracting considerable attention due to its excellent electrical and optical properties. We successfully grew high-quality, large-area and uniform few-layer (FL)-MoS2 on p-doped gallium nitride (p-GaN) using a simplified sulfurization technique by the single-zone CVD of a Mo seed layer via E-beam evaporation. Tuning the sulfurization parameters, namely temperature and duration, has been discovered to be an effective strategy for improving MoS2 orientation (horizontally aligned and vertically aligned) and quality, which affects photodetector (PD) performance. The increase in the sulfurization temperature to 850 °C results in improved structural quality and crystallite size. However, a prolonged sulfurization duration of 60 minutes caused the degradation of the film quality. The close lattice match between p-GaN and MoS2 contributes to the excellent quality growth of deposited MoS2. Following this, an n-MoS2/p-GaN heterostructure PD was successfully built by a MoS2 position-selectivity method. We report a highly sensitive and self-powered GaN/MoS2 p-n heterojunction PD with a relatively high responsivity of 14.3 A W-1, a high specific detectivity of 1.12 × 1013 Jones, and a fast response speed of 8.3/13.4 μs (20 kHz) under a UV light of 355 nm at zero-bias voltage. Our PD exhibits superior performance to that of the previously reported MoS2/GaN p-n PD. Our findings suggest a more efficient and straightforward approach to building high-performance self-powered UV PDs.
  19. Bahadori L, Chakrabarti MH, Manan NS, Hashim MA, Mjalli FS, AlNashef IM, et al.
    PLoS One, 2015;10(12):e0144235.
    PMID: 26642045 DOI: 10.1371/journal.pone.0144235
    The temperature dependence of the density, dynamic viscosity and ionic conductivity of several deep eutectic solvents (DESs) containing ammonium-based salts and hydrogen bond donvnors (polyol type) are investigated. The temperature-dependent electrolyte viscosity as a function of molar conductivity is correlated by means of Walden's rule. The oxidation of ferrocene (Fc/Fc+) and reduction of cobaltocenium (Cc+/Cc) at different temperatures are studied by cyclic voltammetry and potential-step chronoamperometry in DESs. For most DESs, chronoamperometric transients are demonstrated to fit an Arrhenius-type relation to give activation energies for the diffusion of redox couples at different temperatures. The temperature dependence of the measured conductivities of DES1 and DES2 are better correlated with the Vogel-Tamman-Fulcher equation. The kinetics of the Fc/Fc+ and Cc+/Cc electrochemical systems have been investigated over a temperature range from 298 to 338 K. The heterogeneous electron transfer rate constant is then calculated at different temperatures by means of a logarithmic analysis. The glycerol-based DES (DES5) appears suitable for further testing in electrochemical energy storage devices.
  20. Rahim SA, Goh BS, Zainor S, Rahman RA, Abdullah A
    PMID: 29456939 DOI: 10.1007/s12070-017-1193-3
    The cross sectional study was conducted in Universiti Kebangsaan Malaysia Medical Center (UKMMC), Malaysia from August 2012 to December 2013. All patients implanted with in UKMMC from December 2001 until December 2012 was included. Glasgow Benefit Inventory (GBI) questionnaires and UKMMC questionnaires were used as part of the assessment tool. The GBI is a scoring which measures the change in health status produced by surgical interventions. UKMMC questionnaires was invented by our department to assess questions related to social and life style of patients and also the cosmetic perspective Baha implant and other daily related activities. The audiological assessment was assessed using hearing aid gain threshold. Complication with regards to skin reaction was graded using Holger Skin Classification. A total of 40 patients underwent Baha implant were recruited but only 35 patients fulfilled the criteria and included in this study for analysis. Age of patients ranged from 5 year old to 38 year old, with median of 13 years old. There were 22 patients (62.8%) were male and 13 patients (37.1%) were females. Almost all cases were canal atresia except one adult patient was a case of bilateral chronic discharging ear with chronic irritation with ear mould. Majority of patients 21 (60%) have hearing level of moderate to severe hearing loss (40-89 dB) and 14 patients (40%) have mild to moderate hearing loss (20-39 dB). The level of hearing was retested post operatively. All of the patients have improvement in their aided hearing with the range of 10-25 dBL which is statistically significant at p value of <0.05. The GBI was scored positively in all subscales. Majority of patients (91.4%) used BAHA more than 4 h per day and 88.6% agreed that BAHA is cosmetically acceptable. All patients experienced some form of skin irritation (Holger grade 1-2) however only 20% required surgical intervention. All our patients have range of 10-25 dB improvement of their aided hearing which is statistically significant at p value of <0.05. BAHA has been proven to show significant benefit in audiological improvement and quality of life.
Filters
Contact Us

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

External Links