Studies on the persistence and dissipation of deltamethrin (C22H19Br2NO3) in two types of soil, namely peat and silty clay were conducted under laboratory conditions. The analysis was done using a gas chromatography (GC) equipped with an electron capture detector (ECD). The dissipation rate of deltamethrin was faster in silty clay soil than in peat soil at 25°C. When the temperature was increased from 25 to 35°C, the half-life of deltamethrin decreased by 32.53% in peat soil and 22.9% in the silty clay soil in the presence of light. When the same experiment was conducted in the dark, the decrease in the half-life of deltamethrin was 27.9% in peat soil and 22.5% in silty clay soil. When the soil moisture content was increased from 40 to 60%, the half-life of deltamethrin decreased by 50.7 and 19.75% in peat soil and silty clay soil, respectively. A significant degradation rate of deltamethrin was observed in non-autoclaved soil compared with that in autoclaved soil where the half-life was reduced by 76.05% in peat soil and 59.21% in silty clay soil. The results showed that the degradation rate of deltamethrin in soil had a direct relationship with the microbial activity in the soil.
It has not been well known how climate and habitat variables will influence the distribution of plant species to some extents at mesoscales. In this report, by using the distribution of aquatic plants in Western Ghats, a biodiversity hotspot in tropical Asian region, I quantify the relative importance of climate and habitat variables on structuring spatially species richness and taxonomic diversity patterns using structural equation modeling. All the sampling qudrats in the region used for the study has a spatial resolution of 0.5 latitude × 0.5 longitude. The results showed that species richness is high in both northern and southern part of the region, while low in the middle part. In contrast, taxonomic distinctiveness is relatively homogeneous over all the sampling quadrats in the region. Structural equation modeling suggested that taxonomic distinctiveness patterns of aquatic plants in the region follow temperature (partial regression coefficient=0.31, p<0.05) and elevational (partial regression coefficient=0.31, p<0.05) gradients, while richness patterns cannot be explained by any of the currently used variables. In conclusion, environmental variables that are related to taxonomic distinctiveness would not be related to richness, given the fact that these two quantities are orthogonal more or less. Both climate and habitat are equally influential on taxonomic distinctiveness patterns for aquatic plants in Western Ghats of India.
The Malaysian Department of Environment-Water Quality Index (DOE-WQI) was determined for the Terengganu River basin which is located at the coastal water of the southern South China Sea between July and October 2008. Monthly samplings were carried out at ten sampling stations within the basin. Six parameters listed in DOE-WQI were measured based on standard methods: pH, dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS) and ammonical nitrogen (AN). The results indicated the impact of various anthropogenic activities which contribute to high values of BOD, COD, TSS and AN at middle and downstream stations, as compared with the upstream of the basin. The reverses were true for the pH and DO values. The DOE-WQI ranged from 71.5-94.6% (mean 86.9%), which corresponded to a classification status range from slightly polluted to clean. With respect to the Malaysia National Water Quality Standards (NWQS), the level of most of the parameters measured remained at Class I which is suitable for the sustainable conservation of the natural environment, for water supply without treatment and as well as for very sensitive aquatic species. It is suggested that monitoring should be carried out continuously for proper management of this river basin.
MeSH terms: China; Malaysia; Nitrogen; Oxygen; Water Supply; Rivers; Biological Oxygen Demand Analysis; Water Quality
A dwarf tree‑fern, Cyathea arjae Latiff is described as a new species from Sayap, Mt. Kinabalu, Sabah, Malaysia. This new species belongs to Schizocaena group which has basiscopic veins that originate from the costa and not from the costule. It is closely related to C. capitata in having simply pinnate fronds of which the apex is a deltoid lamina. Holttum’s key was modified.
Effects of different incubation methods on crawling and swimming ability of post-emergence green sea turtle (Chelonia mydas) hatchlings at Cherating (Kuantan, Pahang) and Chagar Hutang (Pulau Redang, Terengganu) Turtle Sanctuary were analysed during nesting season in 2009. Mean crawling speed of hatchlings incubated in styrofoam box, beach hatchery and in situ were at 0.042±0.008, 0.136±0.026 and 0.143±0.045 m/s, respectively. Crawling performance of hatclings from styrofoam box can be improved by keeping them for at least 48 h after their emergence. For swimming performance, all types of incubation methods showed significant differences in mean power-stroke rate during their early swimming effort ranging at 93-114 strokes/min. However, no correlation was found between morphological characteristics of hatchlings and swimming performance. The results from this study may give different perspective in evaluating hatchling production, which is in terms of hatchling morphological characteristics and their locomotor performance.
Two new records of moray eels (Muraenidae), Gymnothorax margaritophorus Bleeker, 1864 and Strophidon sathete (Hamilton 1822), are reported for Malaysia. They are represented by two specimens each, all collected from Sabah waters. The present study also provides the current taxonomic and distributional information of the Malaysian moray eels. To date, there are 33 species belonging to six genera of the Muraenidae in Malaysian waters based on the published records.
MeSH terms: Animals; Eels; Malaysia; Publications; Information Dissemination; Physical Phenomena
The present study reports the first complete and inclusive description of some biological parameters including length-frequency distribution (LFD), sex ratio (SR), length-weight relationship (LWR), condition factors (allometric, KA; Fulton’s, KF; relative, KR and relative weight, WR) and form factor (a3.0) of Labeo boga in the Ganges River, northwestern Bangladesh. Sampling was conducted using traditional fishing gears during April 2011 to March 2012. For each specimen, total length (TL) was measured to the nearest 0.01 cm using digital slide calipers and total body weight (BW) was measured using an electronic balance with 0.01 g accuracy. The LWR was calculated using the expression: W= a Lb, where W is the BW and L is the TL. A total of 211 specimens ranging from 9.78-27.50 cm TL and 10.00 to 276.10 g BW were studied. BW of females was significantly higher than that of males (Mann-Whitney U-test, p>0.001). However the overall sex ratio did not differ significantly from the expected value of 1:1 (χ2 = 0.12, p<0.05). The calculated b for the LWR indicated isometric growth (» 3.00) in males, females and combined gender and there were significant differences in the intercepts but not in the slopes between the sexes of L. boga in the Ganges River. KF of females was significantly higher than that for males (p<0.001). In addition, the Wilcoxon signed rank test showed that the WR did not differ from 100 for males and females in this study indicating good condition of habitat for L. boga. The results of this study would be an effective tool for fishery specialists to initiate early management strategies and regulations for the sustainable management of the remaining stocks of this species within the Padma River and surrounding ecosystems.
In a laboratory trial three chickpea varieties viz, Karak-I, Karak-III and Shenghar were tested against the phytotoxicity of five weed species: Parthenium hysterophorus L., Phragmites australis (Cav.) Trin., Datura alba L., Cyperus rotundus L. and Convolvulus arvensis L.in January 2013. The weed extracts were prepared at the rate of 120 g/L (w/v) after shade dry. The results indicated highly significant inhibitory effect of all the tested weed species on the chickpea varieties. The results also showed that the chickpea variety Karak-III was more susceptible to the phytotoxcity of the tested weed extracts. Among the extract, C. arvensis proved much toxic in term of inhibition of germination by giving only 43.33% germination in comparison with control where 97.50% germination was recorded. On the other hand, the effect of P. australis extract was found a little stimulator by speeding the seed germination in all varieties and giving a low (2.21) mean germination time (MGT) value. From the current results it can be concluded that the infestation of C. arvensis can pollute the soil by accumulating toxic chemicals that leads to the germination failure and growth suppression in chickpea. Therefore, the prevention and removal of C. arvensis in the chickpea growing areas could be recommended. In addition, P. australis must be tested against chickpea weeds (chickpea varieties withstand against its phytotoxcity), so that it can be popularized as bioherbicide in chickpea if it gave promising results in controlling chickpea weeds.
The culms of bamboo Bambusa rigida ranging from 1, 3 and 5 year old were obtained and investigated for anatomical characteristics in different ages, heights and zones in radial direction of culm wall thickness. The vascular bundles were denser and smaller at the top portion and outer zone of all age groups. No significant differences in vascular bundle frequency and size were found among the tree age groups. Metaxylem vessels did not vary significantly among ages. Fibre and parenchyma were longer in the middle portion of the height and middle zone in radial direction of culms wall. No significant differences in fibre and parenchyma length were observed in all age groups. The wall thicknesses of fibre and parenchyma were thicker in the top portion and outer zone. Furthermore, the wall thicknesses of fibre and parenchyma increased significantly from 1 to 3 year, showing that there is a maturing progress from 1 to 3 year.
Pollens and seeds of Hypoestes and Rhinacanthus collected from different field localities in Taiz and Soqotra Island, Yemen were investigated by using light and scanning electron microscopes. Pollen grains of Hypoestes were prolate in equatorial view, lobate trigonal to lobate circular in polar view whereas those of Rhinacanthus were subspheroidal and rounded trigonal in polar view. The aperture was tricolporate and exine ornamentation was coarsely reticulate for all species in the two genera. Scanning electron microscopy and morphological observations showed that mature dry seeds of Hypoestes and Rhinacanthus have various sizes and shapes, the surface ornamentations observed were reticulate to cristate, an addition to the tuberculum and papillae. The three Hypoestes species differ in the seed structure which are useful for identification and their high structural diversity provides an important taxonomic value for species differentiation.
The diversity and abundance of Xanthopimpla (Ichneumonidae: Pimplinae) in the secondary and primary forest of Pasoh Forest Reserve (PFR) were studied. A total of 44 individuals of Xanthopimpla and 16 species were recorded. Fifteen species were recorded from the primary forest and only seven species were recorded from the secondary forest. The X. disjunta, X. guptai maculibasis and X. verrucula verrucula were new records for Malaysia. Meanwhile, X. pleurosticta was new record for Peninsular Malaysia. Shannon Diversity Index (H’) indicated that the Xanthopimpla diversity at the primary forest was significantly higher (p<0.001) than the secondary forest in PFR. This suggests that logging activity would cause depletion on insect diversity. In the secondary forest a total of 20 Xanthopimpla individuals were caught, whereas 24 individuals were caught from the primary forest. The individual of Xanthopimpla abundance in primary forest was not significantly (p>0.05) higher than secondary forest. The species domination in the secondary forest was more pronounced compared to the primary forest. In the secondary forests, X. elegans elegans (30.0%) was the highest percentage of total species representation which was higher compared with X. melanacantha melanacantha (16.7%) and X. honorata honorata (16.7%) in the primary forest. This suggests that logging activity would cause disappearance of certain species of Xanthopimpla and at the same time might have provided an opportunity for some species to be dominant over the other species. The evolution of the Xanthopimpla in term of morphological characters changes were also discussed in this paper.
Areca catechu fronds show higher capability for removal of color and COD and were utilized as an adsorbent for adsorption
process. Areca catechu fronds activated carbon (AC) undergoes activation process after carbonization under purified
carbon dioxide and turned as activated carbon. Three variables were chosen for the preparation optimization which
consists of temperature, activation time and impregnation ratio in order to study the effect toward the removal of color
and COD from cotton textile mill wastewater. For this study, the response surface methodology (RSM) was employed.
Quadratic model were develop based on three variables and responses of color and COD. High values of the coefficient
determination, R2
were obtained from analysis of variance (ANOVA) for both responses. The optimum Areca catechu
fronds activated carbon (AC) preparation condition was established at temperature 797 °C for 1.57 hour of activation
time and 2.75 impregnation ratios, corresponding to the removal of color and COD with 78.83 and 62.41%, respectively.
Epoxidized natural rubber (ENR-50) has been used as a compatibilizer for natural rubber-recycled acrylonitrile-butadiene
rubber (NR/NBRr) blends, vulcanized by sulfur. NBR gloves have excellent resistance to punctures, tear and many types
of chemicals, while NR has good physical and mechanical properties. Incorporation of ENR-50 into the rubber blends
has improved processability, stiffness, resilience and excellent oil resistance. NR/NBRr blends were prepared by two-roll
mill with five different compositions with the ENR-50 content fixed at 10 phr. Cure characteristics, mechanical properties
and morphology (SEM) studies were performed to determine the compatibility of NR/NBRr blends in the presence of ENR-
50. The cure characteristics showed that NR/NBRr blends with the presence of ENR-50 have lower scorch time (ts2) and
cure time (t90) than NR/NBRr blends without ENR-50. However, the NR/NBRr blends with ENR-50 exhibited higher minimum
torque (ML
) and maximum torque (MH) which indicated difficult processability of the blends after compatibilization.
Incorporation of ENR-50 into NR/NBRr blends improved all the tensile properties (tensile strength, tensile modulus and
elongation at break) compared with NR/NBRr blends without ENR-50. The improvement in hardness upon compatibilization
is due to an increase in crosslink density. Scanning electron microscopy (SEM images) of the fracture surfaces indicates
that, with the addition of ENR-50 in NR/NBRr blends, better adhesion between NR and NBRr was obtained, thus improving
the compatibility of NR/NBRr blends.
As of today, ultra-high molecular weight polyethylene (UHMWPE) is a thermoplastic material normally used as bearing
components for human joint replacements. However, formation of wear debris from UHMWPE after certain service
periods may cause adverse effects which remain as unresolved issues. In this study, mechanical and dry sliding wear
properties of UHMWPE reinforced with different loading of talc particles were investigated. The wear test was carried
out using Ducom TR-20 pin-on-disc tester at different pressure velocity (pv) factors under dry sliding conditions. The
worn surfaces and transfer films of pure UHMWPE and talc/UHMWPE composites were observed under scanning electron
microscope (SEM). The experimental results showed that the microhardness increased with the increase of talc loadings
in UHMWPE. The 20 wt. % talc/UHMWPE composites showed a 17% increment in microhardness as compared with pure
UHMWPE. The dry sliding wear behaviour of UHMWPE was also improved upon the reinforcement of talc. The wear rate
of UHMWPE decreased after incorporation of talc particles. The coefficient of friction (COF) increased slightly under low
pv conditions. At high pv conditions, the COF decreased in values with increasing talc loadings. The improvement in
wear behaviour may be attributed to the increase in load-carrying capacity and surface hardness of the talc/UHMWPE
composites. SEM micrographs on worn surfaces showed that plastic deformation and grooving wear were dominant for
UHMWPE. The plastic deformation and grooving wear were reduced upon the reinforcement of talc particles. The talc/
UHMWPE composites produced smoother and uniform transfer films as compared to pure UHMWPE.
Laboratory and pot experiments were conducted at the Department of Weed Science, The University of Agriculture
Peshawar, Pakistan during fall 2011 and repeated in 2012. Allelopathic plants were used against wheat and associated
weeds. Allelopathic plants showed significant activity against three selected species - Triticum aestivum, Avena fatua
and Rumex crispus. Aqueous extracts of Parthenium hysterophorus and Datura alba showed significant effect against
weeds of Triticum aestivum although aqueous extract of Phragmites australis possessed moderate activity. It was noted
that aqueous extract of Oryza sativa and control were comparable for all parameters studied. Aqueous extract of P.
hysterophorus and D. alba decreased seed germination, shoot length, fresh and dry biomass as compared to the rest
of the treatments. The degree of toxicity of different treatments can be placed in the following order of inhibition: P.
hysterophorus > D. alba > P. australis > O. sativa ≥ control. The present studies showed that the plants used contain water
soluble allelochemicals that retard or inhibit the germination, growth and biomass of other species. These experiments
suggests that P. hysterophorus, D. alba and P. australis extracts may have negative effect on major weeds like A. fatua
and R. crispus. Thus there is a possibility of using these plant extracts for weed management. However, more extensive
studies is required to identify the allelopathins responsible for inhibitory effects on seed germination and plant growth.
In a forensic acarology study, conducted in a secondary forest of Forensic Science Simulation Site, Universiti Kebangsaan
Malaysia (UKM) in Bangi, Selangor, six carcasses consisted of three monkeys and three rabbits were placed individually
in steel enclosures and observed for 35 days. The carcasses, the soil beneath them and pitfall traps were checked daily
for insects and mites. A species of mesostigmatid mite, Macrocheles scutatiformis was discovered and this is a first time
reported in Malaysia. There are about 94.0% of Macrocheles present inside the cages of the monkey and rabbit carcasses.
Most mites in this study were collected from soil beneath the carcasses, on a dung beetle and a Chrysomya rufifacies
larva. Our findings showed that M. scutatiformis have a potential role in forensic investigation involving dead animals
perhaps corpses especially during the dry stage of decomposition.
Suatu kajian telah dijalankan untuk menentukan potensi makroinvertebrat bentik sebagai penunjuk biologi di hulu Sungai
Ikan, Terengganu. Sebanyak lima stesen pensampelan telah dipilih untuk pensampelan makroinvertebrat bentik dan
analisis kualiti air. Pensampelan makroinvertebrat bentik telah dilakukan menggunakan jaring Surber dan analisis
kualiti air dilakukan menurut kaedah APHA. Piawaian Kualiti Air Kebangsaan (NWQS) telah digunakan untuk menilai
parameter kualiti air di kawasan kajian dan hasil menunjukkan Sungai Ikan berada dalam keadaan baik iaitu kelas I
hingga II. Ujian ANOVA satu hala menunjukkan bahawa kesemua parameter air yang diuji adalah seragam di sepanjang
kawasan kajian (p>0.05, α=0.05). Sebanyak 2 filum, 3 kelas, 8 order, 39 famili dan 1353 individu telah dikenal pasti dan
didominasi oleh famili Baetidae, Siphlonuridae, Simuliidae, Chironomidae dan Elmidae. Famili dominan didapati hadir
pada hampir kesemua stesen pensampelan. Memandangkan kualiti air adalah baik dan tidak berubah sepanjang kawasan
kajian, ujian CCA dilakukan untuk memperlihatkan faktor persekitaran lain yang mempengaruhi sebaran makroinvertebrat
terutamanya famili dominan. Hasil ujian CCA menunjukkan pengaruh persekitaran yang khusus terhadap famili tertentu
dan mempunyai pengaruh yang kuat terhadap sebaran makroinvertebrat bentik. Ujian korelasi menunjukkan batuan
besar mempunyai pengaruh besar terhadap sebaran famili Baetidae, Siphlonuridae dan sub-famili Orthocladiinae,
manakala komposisi pasir pula mempunyai pengaruh terhadap famili Elmidae. Hasil kajian ini menunjukkan dalam
ekosistem yang bersih, faktor persekitaran habitat adalah kritikal untuk diambil kira dalam menentukan taksa tertentu
yang sesuai digunakan sebagai penunjuk biologi ekosistem sungai rekreasi.
Colletotrichum species are well-known causal agent of anthracnose. A study was conducted to determine the identity of Colletotrichum associated with anthracnose of mango (Mangifera indica) fruits. Thirty five Colletotrichum isolates were isolated from anthracnose lesion of two mango cultivars, Chokanan and Harum Manis. Based on the conidial morphology, two morphotypes (I and II) of C. gleosporioides were identified. Based on BLAST search of ITS regions and β-tubulin sequences, majority of the isolates showed 99-100% similarity with Colletotrichum sp. from mango and other hosts and three isolates, 100% similarity with C. asianum. From phylogenetic analysis using maximum likelihood method of combined datasets, the isolates from mango formed three clades, which corresponded to C. gloeosporioides sensu lato and C. asianum. Therefore, the present study showed that the isolates associated with anthracnose of mango belong to C. gleosporioides sensu lato and C. asianum.
Kajian ini dijalankan untuk menentukan kesan penggunaan yis daripada fermentasi beras putih dan perang terhadap
ciri fizikal roti. Yis daripada empat perlakuan fermentasi iaitu beras putih mentah (BP), beras putih dimasak (BPM), beras
perang mentah (BB) dan beras perang dimasak (BBM) telah digunakan untuk penghasilan roti. Kualiti roti dinilai daripada
segi isi padu spesifik, tekstur, saiz, bilangan liang, kandungan kelembapan serta warna. Hasil kajian menunjukkan yis
BBM menghasilkan isi padu spesifik roti yang tertinggi dan tekstur yang paling lembut. Kandungan kelembapan kulit dan
isi roti yang difermentasi oleh yis BBM adalah tertinggi. Bilangan liang yang banyak dan saiz liang yang kecil pada roti
yis BBM telah menghasilkan tekstur yang paling halus dan mempunyai kecerahan (L*) yang tertinggi. Keseluruhannya,
yis BBM menunjukkan potensi sebagai agen penaik dalam industri bakeri.
Currently, oxidative stress (OS) has become a major interest in point of basic science and clinical research. The imbalance between generations and clearances of oxidants leads to OS. Oxidants are mainly composed of reactive oxygen species (ROS) and reactive nitrogen species (RNS) which are manifested as oxidized macromolecules causing deleterious effects in several organs. Lipid, protein and DNA oxidation products can provide extensively approach of potential oxidative stress biomarkers. OS leads to the fundamental cellular and tissue damages and consequence effect to various organs or systems. This review emphasizes the systemic pathology induced by OS that particularly affect to specialized organs or systems including the nervous system, the cardiovascular system, the lung, the liver and the kidney.