This paper reports the effects of glyceryl ether specifically mono-tert-butoxypropanediol on oil in water emulsion system.
Based on 12 HLB value, screening for stable emulsions was carried out without the presence of glyceryl ether. A stable
emulsion was used as a control. Then the effects of glyceryl ether on the emulsion system were investigated. The emulsions
prepared were analyzed for stability, viscosity, pH value, particle size, in vitro dermal irritation potential, in vitro ocular
irritation potential and also moisturizing property. The incorporation of glycerol in the emulsion system was also done
for comparison. Emulsions with glyceryl ether showed lower viscosity values than emulsions with glycerol. Furthermore,
the emulsions also exhibited moisturizing property compared to the control emulsion. Glyceryl ether is suitable to be
used in cosmetic products which require reduced viscosity but retain its skin hydration property.
A new species of the genus Boysidia Ancey, 1881, collected from Doi Pha Tang, Chiangrai Province, Northern Thailand, is described as B. phatangensis sp. nov. The new species is characterized by its small size, conical shape with 5 ¼ - 5 ½ whorls, yellowish-brown color, aperture subquadrate consists of 6 barrier teeth, outer lip expanded. B. phatangensis seem limited to the high altitude area in northern part of Thailand.
The Nipah virus is highly virulent to swine and humans. The envelope attachment glycoprotein (G) of Nipah virus
plays a key role in viral entry and induction of neutralizing antibody in mammalian hosts, thus is considered a good
candidate for vaccine development. Plant transient expression systems are gaining recognition as a viable alternative
for the production of vaccine antigens. In this study, we expressed the Nipah virus G protein heterologously in Nicotiana
benthamiana using an agroinfiltration approach. The highest expression of recombinant G protein in N. benthamiana at
RNA and protein levels was detected on day 9 post-infiltration. Western blot analysis demonstrated that the purified G
protein reacted specifically with rabbit anti-Nipah Virus serum, indicating its potential for vaccine use.
Catalytic hydrogenation of carbon dioxide (CO2) to methanol is an attractive way to recycle and utilize CO2. A series of Cu/ZnO/Al2O3/ZrO2 catalysts (CZAZ) containing different molar ratios of Cu/Zn were prepared by the co-precipitation method. The catalysts were characterized by temperature-programmed reduction (TPR), field emission scanning electron microscopy-energy dispersive x-ray analysis (FESEM-EDX) and X-ray diffraction (XRD). Higher surface area, SABET values (42.6-59.9 m2/g) were recorded at low (1) and high (5) Cu/Zn ratios with the minimum value of 35.71 m2/g was found for a Cu/Zn of 3. The reducibility of the metal oxides formed after calcination of catalyst samples was also affected due to change in metal-support interaction. At a reaction temperature of 443 K, total gas pressure of 3.0 MPa and 0.1 g/mL of the CZAZ catalyst, the selectivity to methanol decreased as the Cu/Zn molar ratio increased, and the maximum selectivity of 93.9 was achieved at Cu/Zn molar ratio of 0.33. With a reaction time of 3h, the best performing catalyst was CZAZ75 with Cu/Zn molar ratio of 5 giving methanol yield of 6.4%.
Invasive fungal infections (IFIs) have risen dramatically in recent years among high risk immunocompromised patients.
Rapid detection of fungal pathogens is crucial to timely and accurate antifungal therapy. Two multiplex polymerase
chain reaction (PCR) assays were developed to detect major fungal species that cause invasive infections and identify
resistant species. Genus specific primers for Candida, Aspergillus, Fusarium and species specific primers for Candida
glabrata, Candida krusei and Aspergillus terreus which are known to be clinically resistant species, were designed from
the internal transcribed spacer (ITS) regions of ribosomal ribonucleic acid (rRNA) gene complex. Both assays were
performed simultaneously to promote rapid detection of fungal isolates based on distinct amplicon sizes. Inclusion of the
universal fungal primers ITS 1 and ITS 4 in the genus specific assay produced a second amplicon for each isolate which
served to confirm the detection of a fungal target. The limit of detection for the genus specific assay was 1 nanogram
(ng) deoxyribonucleic acid (DNA) for Aspergillus fumigatus and Candida albicans, 0.1 ng DNA for Fusarium solani, while
the species-specific assay detected 0.1 ng DNA of A. terreus and 10 picogram (pg) DNA of C. krusei and C. glabrata. The
multiplex PCR assays, apart from universal detection of any fungal target, are able to detect clinically important fungi
and differentiate resistant species rapidly and accurately, which can contribute to timely implementation of effective
antifungal regime.
In this study, the performance of two types of nanocarbons (NCs), namely carbon nanotubes (CNTs) and carbon nanofibers (CNFs), on the three-dimensional shrinkage and swelling properties of three clayey soils were investigated. The specimens of soil mixed with clay with bentonite contents of 0, 10 and 20% by weight of dry soil. NC contents of 0.05, 0.075, 0.10 and 0.20% were chosen to investigate the influence of different NC types, CNTs and CNFs. All soil specimens were compacted under maximum dry unit weight and optimum water content conditions by using standard compaction tests. The physical and mechanical characteristics of the reinforced samples were then determined. These included the desiccation cracking area, used to determine the crack intensity factor (CIF), as well as the shrinkage and swelling. The CIF for the soil specimens without NCs were higher than the soil specimens with NC additives. These results show that NCs decrease the development of desiccation cracks on the surface of compacted samples. The shrinkage and swelling tests showed that the rate of volume changing of the compacted soil specimens reduced with the increasing of NCs.
Acetic acid bacteria (AAB) isolated from natural resources and fermented plant beverages were screened to produce
1,3-dihydroxyacetone (DHA) from non-detoxified crude glycerol. Among them, the isolate NKC115 was identified as
Gluconobacter frateurii and produced the highest amounts of DHA. Subsequently, the effects of growth-medium conditions
(initial pH, crude glycerol concentration and nitrogen sources) on growth and DHA-production capability were examined.
The results showed that the crude glycerol concentration increase to above 100 g/L suppressed growth and DHA production.
The highest amount of DHA obtained was 27.50 g/L, from an initial crude glycerol concentration of 100 g/L. Meanwhile,
an initial pH of 5.5-7.5 in the YPGc medium did not significantly affect the bacterial growth and DHA production. The
optimal nitrogen source was peptone, with DHA production at 34.70 g/L. Furthermore, overexpression of the nhaK2 gene
encoding for the Na+(K+)/H+ antiporter from Acetobactor tropicalis SKU1100 in G. frateurii NKC115 improved growth
and increased the accumulation of DHA (37.25 g/L) from an initial crude glycerol concentration of 20%. These results
indicated that the expression of this antiporter might maintain an optimal intracellular pH and concentration of Na+ or
K+, leading to the cells’ ability to tolerate high concentrations of crude glycerol.
The purpose of this study was to investigate the effect of annealing to the hardness of high Y2O3-oxide dispersion strengthened (ODS) ferritic steels. The samples were prepared by mechanical alloying method followed by Cold Isostatic Pressing (CIP). After compaction process, the samples were sintered at 1100°C for 1 h in a tube furnace. The crystal structure and morphology of samples were analyzed by X-ray Diffraction (XRD) measurement and characterized by using field emission scanning electron microscope (FESEM), respectively. The hardness of samples was measured by using a micro-Vickers hardness tester with a load of 200 gf at annealing temperature of 600°C, 800°C and 1000°C, respectively. The Vickers hardness value (HV0,2) versus annealing temperature graph showed that the hardness of all samples started to decrease at temperature of 600°C due to grain growth. The hardness value of all samples (1Y and 5Y) identified at this annealing temperature is 855 HV0,2 and 808 HV0, 2, respectively.
In recent years, Malaysia has experienced quite a few number of chronic air pollution problems and it has become a
major contributor to the deterioration of human health and ecosystems. This study aimed to assess the air quality data
and identify the pattern of air pollution sources using chemometric analysis through hierarchical cluster analysis (HCA),
discriminant analysis (DA), principal component analysis (PCA) and multiple linear regression analysis (MLR). The air
quality data from January 2016 until December 2016 was obtained from the Department of Environment Malaysia. Air
quality data from eight sampling stations in Selangor include the selected variables of nitrogen dioxide (NO2
), ozone (O3
),
sulfur dioxide (SO2
), carbon monoxide (CO) and particulate matter (PM10). The HCA resulted in three clusters, namely low
pollution source (LPS), moderate pollution source (MPS) and slightly high pollution source (SHPS). Meanwhile, DA resulted
in two and four variables for the forward stepwise mode and the backward stepwise mode, respectively. Through PCA,
it was identified that the main pollutants of LPS, MPS and SHPS came from industrial and vehicle emissions, agricultural
systems, residential factors and natural emission sources. Among the three models yielded from the MLR analysis, it was
found that SHPS is the most suitable model to be used for the prediction of Air Pollution Index. This study concluded that
a clearer review and practical design of air quality monitoring network would be beneficial for better management of
air pollution. The study also suggested that chemometric techniques have the ability to show significant information on
spatial variability for large and complex air quality data.
MeSH terms: Air Pollution; Vehicle Emissions; Carbon Monoxide; Humans; Malaysia; Nitrogen Dioxide; Ozone; Regression Analysis; Sulfur Dioxide; Cluster Analysis; Discriminant Analysis; Linear Models; Ecosystem; Principal Component Analysis; Particulate Matter
In this work, we investigate the effects of Ni doping on the thermoelectric (TE) properties of Yb0.25Co4Sb12 sample. Yb0.25Co4-xNixSb12 (0 ≤ x ≤ 0.5) samples were prepared by mechanical alloying and subsequently consolidated by spark plasma sintering. The morphology of consolidated samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS). The thermoelectric properties of bulk samples were measured from room temperature to 800 K. The XRD analysis confirmed that, the successful formation of the Co4Sb12 skutterudite phase and Ni is substituted into Co site of the skutterudite crystal lattice. Moreover, the electrical resistivity decreased to 14.6 μΩm at 785 K for Yb0.25Co3.5Ni0.5Sb12 sample, due to increase of the electron concentration by Ni-addition. The absolute Seebeck coefficient reached the highest value of 223 μV/K at 592 K for Yb0.25Co3.7Ni0.3Sb12 sample, thus yielding a maximum value of power factor of 2.41 × 10-3 W/mK2 at 592 K. The highest dimensionless thermoelectric figure of merit value ZT of 0.49 at 692 K has been achieved for the Yb0.25Co3.7Ni0.3Sb12 sample, compared to ZT=0.06 for the Yb0.25Co4Sb12 sample at same temperature. This work indicates a strategy to improve the thermoelectric performance by Ni substitution of Co sites in the Yb0.25Co4Sb12 skutterudite through simultaneous improvement of its electrical conductivity, Seebeck coefficient and reduction of its thermal conductivity.
Sungai Selangor is very important from the viewpoint of water supply and multipurpose water use in Malaysia. The
water quality of this river is degrading due to point and non-point sources of pollution. This study, focus on the water
quality assessment and simulation the effect of the pollution sources from urbanization to the Sungai Selangor basin.
Water quality Index (WQI) is used to define the status of river water quality and the QUAL2K was used as a simulation
model. Water quality parameters DO, BOD and NH3
-N have been chosen for modeling. In addition, five different model
scenarios were simulated to observe the impacts of pollution sources on the Sungai Selangor water quality. WQI results
showed that most of the stations in this river basin recorded water inferior to Class III. The water quality model presented
different scenarios for changes of Sungai Selangor water quality. Simulation results for different scenarios showed
that reduced levels of BOD and NH3
-N at 51.10% and 66.18%, respectively, can be obtained if Scenario-5 is employed.
The river water quality issue in the Rawang sub- basin within the study area is considered crucial to create significant
improvement within the sub basin and in the downstream area of Sungai Selangor basin.
MeSH terms: Fresh Water; Malaysia; Urbanization; Water; Water Supply; Rivers; Water Quality
To control the corrosion rate, the Magnesium (Mg) was coated with poly (l-lactic acid) (PLLA) using electrospinning
technique. The effectiveness of the PLLA coating on the high purity Magnesium (HP Mg) and alloy AZ91 were tested in
Hank’s solution immersion test. The corrosion behaviour of Mg coated PLLA was studied through hydrogen evolution,
weight loss and scanning electron microscope (SEM) before, during and after samples were immersed. The solution
was maintained at pH 7 by bubbling CO2
gas. The results showed that surface treatment on Mg by coating with PLLA
had reduced the rate of corrosion during the immersion test. The PLLA coating was also characterized and the coating
adhesion was evaluated.
Forest degradation and deforestation are some of the major global concerns as they can reduce the forest carbon stock
and sequestration capacity. However, the carbon stock and sequestration potential in a mixed dipterocarp tropical forest
remains unclear due to a lack of information. This study was carried out on the carbon stock and estimated its economic
value to justify its conservation. Six plots were established in the Endau Rompin National Park, Johor and subplots
measuring 50 × 20 m were established in each plot. All trees greater than 15 cm DBH (diameter at breast height) were
identified and the parameters measured included tree height and diameter. The aboveground carbon (AGC) content was
about 222 Mg(C) ha-1, belowground carbon (BGC) was 53 Mg (C) ha-1 and it was 6 Mg (C) ha-1 for other components.
In total, the carbon stock amounted to 281 Mg (C) ha-1. On the other hand, the total CO2 sequestrated in the mixed
dipterocarp forest amounted to 1,040 t CO2
ha-1. The carbon value was estimated at RM32,240 t CO2
ha-1 or $7,280 t CO2
ha-1. Therefore, the study found that the dipterocarp forest should be preserved to mitigate greenhouse gas emissions.
Nanosilver particles (NSPs) were produced by the reduction of silver nitrate using glucose as reducer, poly (vinyl pyrrolidone) as stabilizer and sodium hydroxide as reaction enhancer. Two parameters were investigated which are silver nitrate concentration (0.1 M, 0.5 M and 1.0 M) and reaction temperature (60°C and 80°C). Through spectral analysis using ultraviolet-visible spectrophotometer (UV-vis), all the samples recorded the maximum peak in the range of 384-411 nm which verified the formation of NSPs. TEM images showed the nanoparticles have spherical shape with the size range of 25-39 nm. Particle size and zeta potential analysis recorded the hydrodynamic size of nanoparticles in the range of 85-105 nm and the zeta potential ranging from -25 to -30 mV, under the pH value of 8. X-ray diffraction analysis showed that the NSPs have face center cubic (FCC) structure. All the produced NSPs surprisingly showed ferromagnetic-like behaviour based on the magnetization curves. FTIR result confirmed the presence of poly (vinyl pyrrolidone) on the NSPs surface. Furthermore, at the reaction temperature 60°C, the crystallite size, physical size as well as hydrodynamic size increased as the precursor concentration increased from 0.1 M to 0.5 M. However, as the precursor concentration further increases to 1.0 M, the size become smaller due to incomplete reduction process. In contrast, at 80°C, the sizes was gradually increased as the precursor concentration increases up to 1.0 M. In terms of controlled precursor concentration, the crystallite size and physical size become smaller as the temperature increases.
Nocturnal birds in the tropics remain little studied primarily due to the logistical difficulties of surveying these birds at
night. While call playback has been widely employed in the temperate regions, its practicality has not been adequately
demonstrated on tropical owl species. This study aimed to test the feasibility of estimating the density of the Sunda scopsowl
(Otus lempiji) in a lowland forest in Peninsular Malaysia based on call playback and distance sampling. From a
total of 58 detections of the owl species from October 2012 to May 2013, 72.41% (42 detections) were made when the
birds were breeding. The densities of the owl were estimated at 1.6 individuals and 2.6 individuals per 10 ha based on
spontaneous and provoked calls (i.e. before and after call playback), respectively. Broadcasting of the calls significantly
increased the numbers of detections (χ2
= 16.038, p<0.001) during both breeding and non-breeding seasons of the birds.
The combination of call playback and distance sampling improved the detectability as well as precision of the owl’s
density estimation and can be potentially applied on other little known owl species in Southeast Asia.
Thrips (Thysanoptera) are common pests on legume plants, yet little is known about their ecology or diversity in Peninsular
Malaysia. In legumes, thrips are typically found in flowers, where their feeding activity causes malformations that
eventually lead to crop damage. In this study, we examined the diversity of thrips species, particularly Megalurothrips
usitatus, in three selected legume farms around Peninsular Malaysia (Janda Baik, Pahang; Bestari Jaya, Selangor; and
Jelebu, Negeri Sembilan). Each month from April 2013 to May 2014, depending on growing season, legume flowers were
inspected for thrips in five random plots from each farm. Sampling was performed six times in Bestari Jaya and Jelebu
and twelve times in Janda Baik. The most abundant thrips species on legumes was M. usitatus (89.97%) followed by
Thrips parvispinus (9.77%), T. hawaiiensis (0.13%) and Ceratothripoides brunneus (0.12%). The abundance of M. usitatus
was not different between long bean, French bean and winged bean which equally distributed among different arbitrary
strata on legume plants. Temperature and light intensity were found to be positively correlated with the abundance of
M. usitatus, but relative humidity showed a negative relationship. M. usitatus was found in large numbers during hot
and dry months, but in lower numbers during raining season. This study suggested that wet season may help to regulate
the populations of M. usitatus on legume plants.
Cardiovascular disease (CVD) is a major cause of morbidity and mortality in chronic kidney disease (CKD) patients. This study aimed to determine the roles of CVD biomarkers in CKD patients. This was a case-control study which recruited consecutive patients with stage 2-4 CKD patients with and without CVD. Serum levels of highly-sensitive C reactive protein (hs-CRP), cystatin C (CysC), asymmetrical dimetylarginine (ADMA) and symmetrical dimethylarginine (SDMA) were measured. Sixty two stage 2-4 CKD patients with a mean age of 60.3 ± 10.4 years were recruited. Twenty three (37.1%) of them had CVD. Those CKD patients with CVD were older (64.1±8.0 vs 58.1± 1.1, p<0.05) and had significantly higher systolic blood pressure (139.4 ± 16.2 vs 129.4 ± 14.8 mmHg, p<0.05). Diabetic patients had 8 times (95% CI 1.25-51.77, p< 0.05) higher risk to develop CVD. CKD patients with CVD had a higher serum creatinine (185.0 ± 54.1 vs 154.1 ± 54.4 μmol/L, p<0.05), a lower estimated glomerular filtration rate (33.7 ± 12.2 vs 42.2 ± 14.5 mL/min/1.73m2 p<0.05) and a lower triglyceride levels (1.3 (1.1-1.7) vs 1.8 (1.4-2.3) mmol/L, p<0.05), compared to those without CVD. Fasting blood sugar was 7.1 ± 2.7 mmol/L in CVD group and 6.3 ± 1.6 mmol/L in non CVD group (p>0.05). There were no differences in their mean serum levels of hs-CRP, CysC, ADMA and SDMA. Risk factors including age, diabetes mellitus, hypertension and renal functions were still the most important CVD risk factors in CKD patients.
STK15 is a serine/threonine kinase that regulates chromosomal segregation during mitosis. Single nucleotide polymorphisms (SNPs) in this gene, Phe31Ile (rs2273535) and Val57Ile (rs1047972), are inconsistently associated with gastrointestinal cancer (GIC) across different populations. However, this association is unclear in Malaysian population. Therefore, this study investigated the association of STK15 Phe31Ile and Val57Ile polymorphisms to GIC risk in Malaysia. Genomic DNA was extracted from 185 GIC patients and 1110 healthy controls and was subjected to polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. SNPs were further confirmed using sequencing. We found that the 31Phe allele and 31Phe/Phe genotype in the Phe31Ile SNP significantly increased GIC risk in Malaysian population, particularly in gastric cancer (p<0.017). The combined analysis for both SNPs also increased the risk of GIC in this study. Etiological factors such as age, gender and ethnicity were not associated with GIC in the population. This is the first study to report the association of STK15 Phe31Ile and Val57Ile SNPs with an increased risk of GIC in Malaysians; the 31Phe allele is exclusively associated with the risk of gastric cancer. In addition, GIC incidences among Malaysians have significantly shifted to a younger age (<50 years).
The aim of this study was to investigate how various diets influence testis maturation stages in mud crab (Scylla olivacea)
broodstock. Morphological and histological assessments were performed in triplicate (10 male crabs each). Daily,
subject crabs were fed a squid (Loligo sp.) and a fish (Decapterus sp.) diet at 5-10% of body weight. Diets were analyzed
following methods from the Association of Analytical Communities (AOAC). In comparison to control (wild) crabs, the
two diets generally did not cause significant differences (p>0.05) in body weight, carapace width and gonadosomatic
index (GSI), except in the GSI of squid-fed crabs (p<0.05). At the end of the experiment, crabs that reached Stage 3 testis
maturation included were 6 fish-fed individuals and 23 squid-fed individuals. Additionally, differences in crude protein
and fat levels across diets influenced the nature of male gonadal development. In conclusion, a squid diet was sufficient
to induce Stage 3 testis maturation in Scylla olivacea within 60 days of culture. Our results prove the usefulness in
developing appropriate feeding regimes for male Scylla olivacea broodstock.
The objective of this study was to assess the effectiveness of the 5A’s smoking cessation intervention (5A’s) to that of brief advice (BA) conducted by dentists. A single-blinded randomized controlled trial was designed to compare the effectiveness of the interventions. Six Dental Public Health specialists were recruited, randomized and trained to participate in this trial. Two hundred and fifty patients were required on both arms. The main outcome measures were biochemically validated self-reported abstinence and behaviour change at 6-months follow-up. The odd of quitters in 5A’s intervention was 3.81 (95% CI: 1.87-7.76; p= 0.00) times higher compared to BA. After controlling other factors, the odds ratio for the 5A’s was 1.90 (95% CI: 0.652-5.547; p=0.24) higher compared to BA. The 5A’s was found to be more effective in initiating positive behaviour change compared to BA. However, after controlling other factors, there was no difference in the effectiveness although the odds ratio was slightly higher in 5A’s.