Showing papers by "Universiti Sains Malaysia published in 1995"
TL;DR: In this paper, the effect of the coupling agent on the curing and physical properties of the vulcanizates has been investigated using γ-mercapto-propyltrimethoxysilane.
168 citations
TL;DR: The mechanism of inhibition can be related to the cell leakage as observed by irregular, wrinkle shape and loss in rigidity of the macroconidia of Microsporum gypseum which resulted in structural degeneration beyond repair.
155 citations
TL;DR: Patients in the study group showed more rapid improvement in the initial 3 months of the study period than those in the control group, but at the end of the 6 months the difference became nonsignificant.
Abstract: This study was conducted to explore the outcome of psychotherapy in ethnic Malays with strong religious and cultural background. The patients were divided into two groups. The study and control groups consisted of 32 depressed patient each. In the study group brief psychotherapy of 15-20 sessions was attempted with the addition of a religious perspective, while in the control group the religious perspective was omitted. Patients in the study group showed more rapid improvement in the initial 3 months of the study period than those in the control group, but at the end of the 6 months the difference became nonsignificant.
143 citations
TL;DR: In this paper, the effects of applying titanate (LICA 38), zirconate (NZ 44), and silanes (PROSIL 2020 and PROSIL 9234) coupling agents to rice husk ash (RHA) in polypropylene composites are described.
142 citations
TL;DR: Patients with poor compliance who were prescribed drug dosage of not more than twice per day throughout follow‐up and underwent counseling to enhance treatment compliance had a significantly lower relapse rate than the controlled group at the end of 1 year of follow-up.
Abstract: The compliance with drug regimens and follow-up visits of 225 known cases of relapsed schizophrenia was assessed. About 27% of the patients met the criteria for good compliance. The compliance was found to be significantly related to the patients' view of usefulness of the medication, treatment duration of less than 5 years, dosage schedule of once or twice per day and the supervision of medication at home. Patients with poor compliance who were prescribed drug dosage of not more than twice per day throughout follow-up and underwent counseling to enhance treatment compliance had a significantly lower relapse rate than the controlled group at the end of 1 year of follow-up. The importance of family support and understanding patients' cultural background in ensuring good compliance was highlighted.
120 citations
TL;DR: The results indicate that highly religious patients with grief and bereavement tend to improve faster when a religious psychotherapy is added to a cognitive‐behaviour approach.
Abstract: This study was aimed at determining the effect of psychotherapy in patients in bereavement. Fifteen patients in a control group were given brief psychotherapy and 15 study group patients received psychotherapy with a religious perspective. The patients in the study group showed consistently significant improvements as compared with the control group at the end of 6 months. The results indicate that highly religious patients with grief and bereavement tend to improve faster when a religious psychotherapy is added to a cognitive-behaviour approach.
119 citations
01 Jan 1995-Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology
TL;DR: For the first time in vertebrates, hormone-induced plasticity of primary chemosensory neuronal responsiveness to an ethologically relevant compound is demonstrated at the level of the peripheral sensory neurons.
Abstract: Although it is well known that responses to ethologically-relevant odors are influenced by endocrine factors, it has not been clear whether these hormonal effects might be mediated at the level of the peripheral sensory neurons. During an investigation of hormonal pheromones in South-East Asian Cyprinids, we observed that in adult male Puntius schwanenfeldi, an androgen-dependent sex character was correlated with electro-olfactogram response to a putative sex pheromone (15-keto-prostaglandin-F2α). As secondary sex characteristics are androgen-dependent in male teleosts, this observation suggested a functional relationship between androgen and peripheral olfactory receptor response. We therefore investigated this possibility using androgen implants.
96 citations
TL;DR: In this article, the effectiveness of government-run permanent relocation schemes as a response to flood hazards in Malaysia is examined, and the authors conclude that relocation is unpopular, as plans to relocate entire communities are costly, mainly because of the need to acquire alternative locations and the provision of housing for those resettled.
Abstract: In disaster management, relocation/resettlement is more often seen as the worst option as it gives the impression that nothing else can be done about the hazard and people have to be moved. Relocation is unpopular, as plans to relocate entire communities are costly, mainly because of the need to acquire alternative locations and the provision of housing for those resettled. More significantly, at least on the part of those being relocated, it provokes social disruption and upheaval when people are bundled into an alien environment. Notwithstanding the influence of structural/societal forces, people are also reluctant to be relocated far from relatives, friends and their place of work (or schools in the case of children). Examines the effectiveness of government‐run permanent relocation schemes as a response to flood hazards in Malaysia.
94 citations
TL;DR: In this paper, residual from the mechanical processing of palm oil was treated with supercritical-fluid extraction (SFE) to extract carotenes and tocopherols.
Abstract: Residue from the mechanical processing of palm oil was treated with supercritical-fluid extraction (SFE) to extract carotenes This was done at different extraction conditions Also, leaves of palm oil trees were extracted using supercritical fluid to gain high concentrations of tocopherols in the extract The aim of these SFE experiments was to evaluate whether either the carotene or tocopherol contents of the extracts were sufficiently high enough to allow downstream processing of these waste products In addition, solubility data for α-tocopherol in supercritical carbon dioxide in a density range of 220–930 kg m−3 were measured
85 citations
TL;DR: The figure of 1% per year given by Ong (1982) for Malaysia can be taken as a conservative estimate of destruction of mangroves in the Asia-Pacific region.
Abstract: Despite the recent better understanding and awareness of the role of mangroves, these coastal forest communities continue to be destroyed or degraded (or euphemistically reclaimed) at an alarming rate. The figure of 1% per year given by Ong (1982) for Malaysia can be taken as a conservative estimate of destruction of mangroves in the Asia-Pacific region. Whilst the Japanese-based mangrove wood-chips industry continues in its destructive path through the larger mangrove ecosystems of the region, the focus of mangrove destruction has shifted to the conversion of mangrove areas into aquaculture ponds and the consequences of the unprecedented massive addition of carbon dioxide to the atmosphere by post industrial man.
70 citations
TL;DR: In this paper, the first direct experimental evidence for the existence of magnetic surface polaritons in a uniaxial antiferromagnet is presented, where the modes are excited in Fe${\mathrm{F}}_{2}$ by attenuated total reflection with the uniaXis along an applied magnetic field.
Abstract: We present the first direct experimental evidence for the existence of magnetic surface polaritons in a uniaxial antiferromagnet. The modes are excited in Fe${\mathrm{F}}_{2}$ by attenuated total reflection with the uniaxis along an applied magnetic field ${H}_{0}$. The resonance is observed as an attenuation of the reflected intensity as the frequency of the far-infrared beam is scanned. We find nonreciprocity between the $+{H}_{0}$ and $\ensuremath{-}{H}_{0}$ spectra as a consequence of the nonreciprocity of the surface polariton modes when ${H}_{0}$ is introduced. We also observe broad dips due to the excitation of bulk modes.
TL;DR: It is shown that the ingestion of a 5.5% CHO solution improves marathon running performance and blood glucose and lactate, and hormonal responses to fluid ingestion were similar in all three trials.
Abstract: The aim of this study was to compare the effects of drinking two carbohydrate (CHO) electrolyte solutions and water on marathon running performance. Seven endurance-trained runners completed three 42.2-km treadmill time-trials which were randomly assigned and 4 weeks apart. On each occasion the subjects ingested 3 ml · Kg−1 body weight of either water (W), a 6.9% CHO solution (O) or a 5.5% CHO solution (L) immediately prior to the start of the run and 2 ml · kg−1 body weight every 5 km thereafter. The total volume of fluid ingested [mean (SEM)] was 1112 (42), 1116 (44) and 1100 (44) ml, respectively. Running times for W, O and L trials were 193.9 (5.0), 192.4 (3.3) and 190.0 (3.9) min, respectively. Performance time for the L trial was faster (P < 0.05) compared with that of the W trial. Running speed was maintained in the L trial, whereas it decreased after 10 km (P < 0.05) in the W and after 25 km (P < 0.05) in the O trial. Blood glucose and lactate, and hormonal responses to fluid ingestion were similar in all three trials. Higher plasma free fatty acid and glycerol concentrations were observed at the end of the W trial compared with those obtained after the O and L trials, respectively (P < 0.05). Plasma ammonia concentration was higher (P < 0.01) at the end of the L trial compared with the W trial. Plasma creatine kinase concentration was higher (P < 0.05) 24 h after the completion of the L trial than after the W trial. This study shows that the ingestion of a 5.5% CHO solution improves marathon running performance.
TL;DR: The Matang Mangrove Forest Reserve in Malaysia has been managed for timber production since the beginning of the century and is reputedly the best managed mangrove forest in the world as discussed by the authors.
Abstract: The Matang Mangrove Forest Reserve in Malaysia has been managed for timber production since the beginning of the century and is reputedly the best managed mangrove forest in the world. The present management plan is a 30-year rotation period with two thinnings, at 15 and 20 years. However, there has been a decline in yield from 299 t ha−1 of green-wood from virgin stands to the second generation yields of 158 t ha−1 in 1967–69 to an even lower 136 t ha−1 in 1970–77.
TL;DR: In this paper, a convex combination of all derivatives on related triangular planes is used to estimate the derivative values at the vertices of the data points, and the method has comparable accuracy to the existing method of least squares minimization but with less computation.
TL;DR: In this paper, the thermal degradation temperature of white rice husk ash (WRHA) composites was found to be independent of filler loading but the oxidative stability deteriorated with increasing filler content.
Abstract: Incorporation of rice husk ash (RHA) fillers into polypropylene affected some of the thermal properties of polypropylene composites. Addition of the black rice husk ash (BRHA) filler raised the thermal degradation temperature while maintaining the oxidative stability. The thermal degradation temperature of the white rice husk ash (WRHA) composites was found to be independent of filler loading but the oxidative stability deteriorated with increasing filler content. DSC studies indicated that both white and black RHA fillers act as weak nucleation agents and increase the degree of crystallinity of polypropylene by a small margin. Addition of the RHA fillers reduced the linear thermal expansion coefficient of the composites. Dynamic mechanical studies showed that the RHA composites with higher filler content have higher storage modulus. Tan δ curves of the composites indicated that WRHA filler increased the damping property while the BRHA filler had an opposite effect.
TL;DR: The suitability of the ENR-APS precured sample for in-situ silica reinforcement by the sol-gel process, using tetraethyl orthosilicate (TEOS) as the silica precursor, was also demonstrated as mentioned in this paper.
Abstract: Epoxidized natural rubber (ENR) was first precured with 3-aminopropyltriethoxysilane (APS) by the normal compression molding technique. The resultant sheet was further subjected to moisture cure, via hydrolysis and condensation reactions, by soaking it in water. The moisture-cured sample, when prepared under appropriate reaction conditions, demonstrated partial strain-induced crystallization behavior and moderate tensile strength, as opposed to typical peroxide-cured and sulfur-cured vulcanizates. The suitability of the ENR-APS precured sample for in-situ silica reinforcement by the sol-gel process, using tetraethyl orthosilicate (TEOS) as the silica precursor, was also demonstrated. Silica content as high as 36% by weight could be incorporated into the rubber, and TEOS-to-silica conversion of over 60% was observed. Comparative analysis with a typical peroxide-cured sample that was subjected to the same sol-gel process indicates that the silica in the final ENR-APS sol-gel vulcanizate is chemically bound to the rubber network.
TL;DR: A selective reproducible high-performance liquid chromatographic assay for the simultaneous quantitative determination of the antimalarial compound artemether (ARM), dihydroartemisinin (DQHS) and artemisinIn (QHS), as internal standard, was found to be suitable for use in clinical pharmacological studies.
TL;DR: The technical viability of using rice husk ashes (RHA) as alternative fillers in polypropylene was studied in this paper, where the RHA composites were compounded by twin screw compounders and the mechanical properties of the composites evaluated.
Abstract: The technical viability of using rice husk ashes (RHA) as alternative fillers in polypropylene was studied. Three types of RHA, white rice husk ash (WRHA), black rice husk ash (BRHA) and amorphous rice husk ash (AMRHA) at 10—40 wt% filler loading were investigated. The RHA composites were compounded by twin screw compounders and the mechanical properties of the composites evaluated. Incorporation of the RHA fillers increased the flexural modulus of the composites, particularly the BRHA composities. Modulus of the RHA composites were found to be in good agreement with theoretical values predicted by equation of Lewis and Nielsen. The increase in modulus was offset by lowering of the tensile strength, elongation at break and impact properties. Theoretical treatments of the ultimate tensile strength performed based on the model proposed by Nicolai and Nicodemo showed reasonably good agreement. The mechanical properties of the RHA composites were of comparable values with the prepared polypropylene composites filled with commercial Neuburg silica. Transformation of the crystalline RHA to amorphous RHA resulted in composites with improved tensile strength. No coupling agent was used in this study.
TL;DR: The release study of triamcinolone acetonide from various bioadhesive buccal tablets containing different proportions of poly(acrylic acid-2.5-dimethyl-1,5-hexadiene) (PADH) and hydroxypropylmethyl-cellulose (HPMC) with the apparatus reveals that the bioadhesion of the tablet and the release of drug are influenced by the different proportionsof polymers.
Journal Article•
TL;DR: Several parameters on the oviposition site preference of Aedes albopictus were studied, including color, container type, salinity, and water type, and dark-colored glass jars were preferred over light-colored jars.
Abstract: Several parameters on the oviposition site preference of Aedes albopictus were studied, including color, container type, salinity, and water type. Dark-colored glass jars, especially black, blue, and red ones were preferred over light-colored jars. The black-colored ovitrap with a paper strip performed better than other types of containers. Seasoned tap water had the highest egg count when compared with a saline water series. In addition, water that had previously been used for the culture of Ae. albopictus was the most preferred for oviposition. The significance of this study in conjunction with the present Aedes mosquito surveillance and monitoring program is discussed.
TL;DR: The volatile constituents of three different clones of durian (Durio zibethinus Murr) were isolated by vacuum distillation with subsequent extraction of the distillates with dichloromethane as mentioned in this paper.
Abstract: The volatile constituents of three different clones of durian (Durio zibethinus Murr.) were isolated by vacuum distillation with subsequent extraction of the distillates with dichloromethane. The concentrated extracts were analysed by capillary GC and GC-MS. A total of 63 constituents were identified, comprising 30 esters, 16 sulphurcontaining compounds, 5 ketones, 8 alcohols and 4 miscellaneous compounds. All three clones produced approximately the same proportions of esters and of ketones. The first-mentioned chemical class was quantitatively the most important among durian volatiles. There was much variation in the content of sulphur volatiles among the three clones. Identified among this chemical class were some uncommon plant volatiles such as cis- and trans-3,5-dimethyl-1,2,4-trithiolane and S-alkyl esters of alkylthiocarboxylic acids.
TL;DR: In this article, the sol-gel technique was employed to prepare silica-reinforced vulcanizates using tetraethylorthosilicate (TEOS) and epoxidized natural rubber (ENR).
Abstract: The sol-gel technique was employed to prepare silica-reinforced vulcanizates using tetraethylorthosilicate (TEOS) and epoxidized natural rubber (ENR). The rubber was first precured with 3-aminopropyltriethoxysilane (APS) by heat pressing at 180°C for a range of cure time. The resultant rubber sheets or vulcanizates were swelled in TEOS, and subsequently subjected to a sol-gel reaction in butylamine aqueous solution. Hydrolysis and condensation of the TEOS resulted in the formation of silica particles in the rubber network yielding silica-contained vulcanizates. Silica content as high as 28% and TEOS-to-silica conversion of over 60% were observed. When prepared under certain reaction conditions, the sol-gel vulcanizates obtained were more rigid and stronger than a typical sulfur-cured ENR vulcanizate that contained comparable amount of silica. Comparative stress-strain and dynamic mechanical property analysis suggest that chemicals bond are formed between the silica particles and the rubber network in the ENR-APS-sol-gel vulcanizate. Thus, the “in situ” silica reinforcement of ENR was successfully established.
TL;DR: In this article, the reversion behavior of two grades of epoxidized natural rubber (ENR 25 and 50) was investigated in the temperature range from 140 to 180 °C in an accelerated sulphur vulcanization system.
TL;DR: In Peninsular Malaysia, poorer individuals seldom attempt to leave for more advantageous locations but are instead trapped in their present locations by structural factors such as poverty, low residential and occupational mobility, low educational attainment, traditional land inheritance, government aid, and government disaster preparedness, relief and rehabilitation programmes.
Abstract: In Peninsular Malaysia ‘structural‘ factors are found to influence strongly people's persistent occupation of floodplains. Thus, despite a high level of flood hazard awareness, a high level of pessimism and a high level of expectation of future floods, poorer individuals seldom attempt to leave for more advantageous locations but are instead trapped in their present locations by structural factors such as poverty, low residential and occupational mobility, low educational attainment, traditional land inheritance, government aid, and government disaster preparedness, relief and rehabilitation programmes. These forces exert a strong influence upon individuals and largely control their choice of residential location in response to flood hazards, thereby reinforcing the persistent occupation of floodplains. Structural factors such as lawlessness, rural—urban migration, floodplain encroachment and squatting are also highly influential in leading people to move. Even for those who move, structural factors have largely confined their choice of residential location to urban floodplains.
TL;DR: In this paper, the authors examined locally available ceramic utensils (cups, bowls, sauce plates, cooking pots and spoons) as possible sources of lead poisoning and found that 54.7% of the sample items tested exceeded the US PDA maximum permitted lead release from earthenware.
TL;DR: In this paper, the crystalline structures of α-Si3N4 and β-Si4 made from rice husk were obtained at room temperature (300 K) from X-ray powder diffraction with CuKα radiation using Rietveld analysis for the two phase mixture.
TL;DR: It is speculated that the endoperoxide moiety accounts for the response to the electron-capture detector and thus provides a new approach by which this class of compounds may be analyzed.
TL;DR: The effect of stearic acid on Mooney scorch time of epoxidized natural rubber and one grade of unmodified natural rubber (SMR L) was investigated in the concentration range of 0.5 to 14.5 phr as discussed by the authors.
Abstract: The effect of stearic acid on Mooney scorch time of epoxidized natural rubber (ENR 25 and ENR 50) and one grade of unmodified natural rubber (SMR L) was investigated in the concentration range of 0.5 to 14.5 phr. Other parameters, namely accelerator systems, temperature, and fillers (carbon black and silica), on the scorch property of ENR 25 in the presence of excess loading of stearic acid were also studied. Results indicate that scorch time increases with stearic acid loading for all the rubbers investigated, the rate of increase being fastest in ENR 50, followed by ENR 25 and SMR L. Mooney scorch time of ENR shows strong dependence on stearic acid loading for delay-action accelerators and at lower temperature of vulcanization. For a fixed filler loading, the dependence of scorch time on stearic acid concentration is similar to that of gum stock. The retardation effect exhibited by excess stearic acid on the vulcanization of ENR may be attributed to complex formation of chelates and the reduction in activation of adjacent double bonds in ENR resulting from interaction between stearic acid and the epoxide group of ENR. © 1995 John Wiley & Sons, Inc.
TL;DR: Using the effective-medium theory, the surface polaritons of a lateral antiferromagnetic nonmagnetic superlattice in the Voigt geometry are investigated and some interesting analytical results are obtained.
Abstract: Using the effective-medium theory, we investigate the surface polaritons of a lateral antiferromagnetic nonmagnetic superlattice in the Voigt geometry and obtain some interesting analytical results. Calculation dispersion curves for a ${\mathrm{FeF}}_{2}$/${\mathrm{ZnF}}_{2}$ superlattice show differences in dispersion properties from a pure semi-infinite antiferromagnet and common antiferromagnetic nonmagnetic superlattice. (i) For ${\mathit{H}}_{0}$=0, the surface mode only exists in the condition 1\ensuremath{\ge}${\mathit{f}}_{1}$\ensuremath{\ge}0.5 (${\mathit{f}}_{1}$ is the antiferromagnetic fraction and ${\mathit{H}}_{0}$ indicates the field) and when ${\mathit{f}}_{1}$\ensuremath{
e}1.0, the surface mode no longer starts from the boundary of the corresponding bulk continuum. For ${\mathit{f}}_{1}$=0.5 no virtual surface mode is found. (ii) For ${\mathit{H}}_{0}$\ensuremath{
e}0, three surface-polariton modes are obtained and one of them partly enters the bulk continuum. As ${\mathit{f}}_{1}$0.5 only two surface modes can exist. They are virtual and in the bulk continuum. The computed attenuated total reflectivity is also presented.