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A Preliminary Genetic Investigation of Rastrelliger Kanagurta Based on Random Amplified Polymorphic DNA and Mitochondrial ND2 Gene

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湿地科学 2008年第4期6卷 518-525页

作者： Siti Azizah mohd nor Abu Talib A mohd Ghows M A Samsudin B Aquaculture Research Group School of Biological Sciences University Sains Malaysia 11800 Minden Penang Malaysia Fisheries Research Institute 11900 Batu Maung Penang Malaysia

In a preliminary investigation, Random Amplified Polymorphic DNA (RAPD) analysis and partial mitochondrial ND2 gene sequencing were conducted to study the genetic variation of the Indian mackerel, Rastrelliger kanagurta along a 450 km stretch of its distribution on the west coast of Peninsular Malaysia. A total of 53 individuals from 6 populations were analyzed using 4 RAPD primers and a sub-sample of 15 individuals was chosen for sequencing of partial ND2 gene. Comparison between the 2 markers revealed genetic structuring in the RAPD results but genetic homogeneity for ND2 gene. Based on the former there may be at least 2 genetically differentiated groups of Rastrelliger kanagurta along this stretch.

关键词：基因 DNA分析分析方法生物技术水生生物

Distribution of Chironomidae (Insecta: Diptera) in polluted rivers of the Juru River Basin, Penang, Malaysia

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Journal of Environmental Sciences 2010年第11期22卷 1718-1727页

作者： Salman A. Al-Shami Che Salmah Md Rawi Abu HassanAhmad Siti Azizah mohd nor School of Biological Sciences Universiti Sains Malaysia Centre for Marine and Coastal Studies Universiti Sains Malaysia

The influence of physical and chemical parameters on the abundance and diversity of chironomids was studied in six rivers with moderate to highly polluted water in the Juru River Basin. The rivers: Ceruk Tok Kun (CTKR) as reference site, and polluted rivers of Pasir (PR), Juru (JR), Permatang Rawa (PRR), Ara (AR) and Kilang Ubi (KUR) were sampled over a period of five months (November 2007-March 2008). Nine chirnomid species: Chironimus kiiensis, C. javanus, Polypedilum trigonus, Microchironomus sp., Dicrotendipes sp., Tanytarsus formosanus, Clinotanypus sp., Tanypus punctipennis and Fittkauimyia sp. were identified. Assessment of their relationships with several environmental parameters was performed using the canonical correspondence analysis (CCA). Tanytarsus formosanus was the most dominant in the relatively clean CTKR and moderately polluted JR with mean densities of 19.66 and 25.32 m 2 , respectively while C. kiiensis was abundant in more polluted rivers. Tanytarsus formosanus, Dicrotendipes sp. and Microchironomus sp. were grouped under moderate to high water temperature, total organic matter (TOM), total suspended solids (TSS), velocity, pH, phosphates and sulphates. However, Tanypus punctipennis, Fittkauimyia sp., and Clinotanypus sp. were associated with high contents of river sediment such as TOM, Zn and Mn and water ammonium-N and nitrate-N and they were associated with higher dissolved oxygen (DO) content in the water. Chironomus kiiensis, C. javanus and P. trigonus showed positive relationships with TOM, ammonium-N and nitrate-N as well as trace metals of Zn, Cu and Mn. These three species could be considered as tolerant species since they have the ability to survive in extreme environmental conditions with low DO and high concentrations of pollutants. Based on the water parameter scores in all rivers, the highest diversity of chironomid larvae was reported in CTKR. With higher concentrations of organic and/or inorganic pollutants as reported in PPR, K

关键词： chironomid larvae Juru River physicochemical parameters canonical correspondence analysis

Recovery of bird communities following the construction of a large-scale hydroelectric dam

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Ecological Processes 2021年第1期10卷 408-417页

作者： Affan Nasruddin-Roshidi Mohammad Saiful Mansor nor Adibah Ismail Ehwan Ngadi mohd Izzat-Husna Shahril Mod Husin Farah Shafawati mohd-Taib Rahmah Illias Shukor Md nor Department of Biological Sciences and Biotechnology Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 BangiSelangorMalaysia Kolej GENIUS Insan Universiti Sains Islam MalaysiaBandar Baru Nilai71800 NilaiNegeri SembilanMalaysia TNB Research Sdn Bhd No.1Kawasan Institusi PenyelidikanJalan Ayer Itam43000 KajangSelangorMalaysia Department of Wildlife and National Parks(PERHILITAN) Km.10Jln Cheras56100 Kuala LumpurWilayah PersekutuanMalaysia.

Background:Habitat degradation is known to have a major impact on the composition of bird communities,yet how these communities recover following such disturbance is less *** study examined bird community changes from pre-logging to recovery over the course of habitat disturbance caused by the development of the Hulu Terengganu Hydroelectric Dam Project in Peninsular Malaysia,between 2007 and *** surveys were conducted using point count observations and mist netting in the dam area from the prelogging phase until the operation ***:It was observed that while bird species significantly declined after large-scale habitat clearance between the pre-logging and construction phases,they showed positive signs of recovery from the inundation to operation *** findings indicate that the bird community is still recovering,and the permanent loss of habitat required by most of the original species has not occurred,as evidenced by *** species composition differed across phases due to varying habitat *** turnover rate and immigration rate(recolonisation and newly recorded species)were higher between the construction and operation *** was also observed that insectivorous birds were more heavily affected than others by changes to the landscape,which highlights the versatility,survivability and tolerance of certain species to extreme disturbance and habitat ***:Although the operation phase showed an incremental change in bird species richness due to recolonisation and newly recorded species,this value remains far from that of the pre-logging *** predict that bird species recovery will continue to increase for some time before reaching a plateau among the newly created islands,reservoir and catchment area of the dam.

关键词： Dam construction Extinction Habitat recovery Recolonisation Turnover

Microbial synthesis of zinc oxide nanoparticles and their potential application as an antimicrobial agent and a feed supplement in animal industry: a review

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Journal of Animal Science and Biotechnology 2019年第4期10卷 851-872页

作者： Hidayat mohd Yusof Rosfarizan Mohamad Uswatun Hasanah Zaidan nor’Aini Abdul Rahman Department of Bioprocess Technology Faculty of Biotechnology and Biomolecular SciencesUniversiti Putra Malaysia43400 SerdangSelangorMalaysia Bioprocessing and Biomanufacturing Research Centre Faculty of Biotechnology and Biomolecular SciencesUniversiti Putra Malaysia43400 SerdangSelangorMalaysia Department of Biochemistry Faculty of Biotechnology and Biomolecular SciencesUniversiti Putra Malaysia43400 SerdangSelangorMalaysia

In recent years, zinc oxide nanoparticles(ZnO NPs) have gained tremendous attention attributed to their unique properties. Notably, evidence has shown that zinc is an important nutrient in living organisms. As such, both prokaryotes and eukaryotes including bacteria, fungi and yeast are exploited for the synthesis of ZnO NPs by using microbial cells or enzyme, protein and other biomolecules compounds in either an intracellular or extracellular route. ZnO NPs exhibit antimicrobial properties, however, the properties of nanoparticles(NPs) are depended upon on their size and shape, which make them specific for various applications. Nevertheless, the desired size and shape of NPs can be obtained through the optimization process of microbes mediated synthesis by manipulating their reaction conditions. It should be noted that ZnO NPs are synthesized by various chemical and physical ***, these methods are expensive and not environmentally friendly. On that account, the microbes mediated synthesis of ZnO NPs have rapidly evolved recently where the microbes are cleaner, eco-friendly, nontoxic and biocompatible as the alternatives to chemical and physical practices. Moreover, zinc in the form of NPs is more effective than their bulk counterparts and thus, they have been explored for many potential applications including in animals industry. Notably, with the advent of multi-drug resistant strains, ZnO NPs have emerged as the potential antimicrobial agents. This is mainly due to their superior properties in combating a broad spectrum of pathogens. Moreover, zinc is known as an essential trace element for most of the biological function in the animal’s body. As such, the applications of ZnO NPs have been reported to significantly enhance the health and production of the farm animals. Thus, this paper reviews the biological synthesis of ZnO NPs by the microbes, the mechanisms of the biological synthesis, parameters for the optimization process and their potential

关键词： Animals Antimicrobial Feed supplement Microbial synthesis Nanotechnology Zinc oxide nanoparticles

Effects of electron radiation on commercial power MOSFET with buck converter application

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Nuclear Science and Techniques 2017年第3期28卷 30-34页

作者： Sheik Fareed Ookar Abubakkar nor Farahidah Zabah Yusof Abdullah Dhiyauddin Ahmad Fauzi norasmahan Muridan nurul Fadzlin Hasbullah Department of Electrical and Computer Engineering International Islamic University Kuala Lumpur 53100Malaysia Industrial Technology Division Agency Nuclear MalaysiaKuala Lumpur 43000 Malaysia

Microelectronic power converters such as buck and boost converter are required to be tolerant to radiations including electron radiation. This paper examines electron radiation effects on the Ⅰ-Ⅴ characteristics of VDMOSFET and its corresponding effects in buck converter. Analysis of the electrical characteristics shows that after irradiation the threshold voltage and drain current for all VDMOSFETs degraded more than two orders of magnitude. The impact of this electrical degradation has been investigated in an application of typical buck converter circuit. The buck converter with n-channel switching transistor shows that after irradiation its output voltage increased with the drain current in the n-channel ZVN4424 A VDMOSFET, while the buck converter with p-channel switching transistor shows its output voltage decreased with the drain current in the p-channel ZVP4424 A VDMOSFET after irradiation.

关键词： VDMOSFET I–V characteristics Drain current Buck converter Electron radiation

Piper sarmentosum as an antioxidant on oxidative stress in human umbilical vein endothelial cells induced by hydrogen peroxide

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第5期11卷 357-365页

作者： Abdul Hamid HAFIZAH Zakaria ZAITON Amom ZULKHAIRI Adenan mohd ILHAM Megat mohd nordin nor ANITA Abdullah Mahdy ZALEHA Department of Physiology Universiti Kebangsaan Malaysia Medical CentreJalan Raja Muda Aziz50300 Kuala LumpurMalaysia Department of Human Anatomy Division of PhysiologyFaculty of Medicine and Health SciencesUniversiti Putra Malaysia Forest Research Institute of Malaysia Department of Obstetrics and Gynecology Universiti Kebangsaan Malaysia Medical Centre

Endothelial cell death due to increased reactive oxygen species(ROS) may contribute to the initial endothelial injury,which promotes atherosclerotic lesion *** sarmentosum(PS),a natural product,has been shown to have an antioxidant property,which is hypothesized to inhibit production of ROS and prevent cell ***,the present study was designed to determine the effects of PS on the hydrogen peroxide(H2O2)-induced oxidative cell damage in cultured human umbilical vein endothelial cells(HUVECs).In this experiment,HUVECs were obtained by collagenase perfusion of the large vein in the umbilical cord and cultured in medium M200 supplemented with low serum growth supplementation(LSGS).HUVECs were treated with various concentrations of H2O2(0-1000 μmol/L) and it was observed that 180 μmol/L H2O2 reduced cell viability by 50% as denoted by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) *** the above concentration as the positive control,the H2O2-induced HUVECs were concomitantly treated with various concentrations(100,150,250 and 300 μg/ml) of three different extracts(aqueous,methanol and hexane) of ***(MDA),superoxide dismutase(SOD),catalase(CAT) and glutathione peroxidase(GPX) levels showed a significant increase(P<0.05) in HUVECs compared to the negative ***,PS extracts showed a protective effect on HUVECs from H2O2-induced cell apoptosis with a significant reduction in MDA,SOD,CAT and GPX levels(P<0.05).Furthermore,PS had exhibited ferric reducing antioxidant power with its high phenolic ***,it was concluded that PS plays a beneficial role in reducing oxidative stress in H2O2-induced HUVECs.

关键词： Piper sarmentosum Human umbilical vein endothelial cells(HUVECs) Malondialdehyde Oxidative stress Antioxidant enzymes

Copper oxide nanoparticles-loaded zeolite and its characteristics and antibacterial activities

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Journal of Materials Science & Technology 2017年第8期33卷 889-896页

作者： Abdullah A.Alswat Mansor Bin Ahmad mohd Zobir Hussein nor Azowa Ibrahim Tawfik A.Saleh Department of Chemistry Faculty of ScienceUniversiti Putra MalaysiaSelangor 43400Malaysia Department of Chemistry Sana'a UniversityYemen Department of Chemistry King Fahcl University of Petroleum&MineralsDhahran 31261Saudi Arabia

In the present work, a simple and green co-precipitation method was used to prepare copper oxide-zeolite nanocomposites（CuO-zeolite NCs）. The weight ratio（1, 3, 5, 8 and 10 wt%） of CuO nanoparticles（NPs）loaded into zeolite was investigated to obtain the optimum CuO distribution for antibacterial *** prepared CuO-zeolite NCs were characterized by ultraviolet-visible（UV–vis） spectroscopy, Fourier transform infrared（FT-IR） spectroscopy, powder X-ray diffraction（XRD）, and energy dispersive X-ray fluorescence spectrometry（EDXRF）. The transmission electron microscopy（TEM） and field emission scanning electron microscopy（FE-SEM） revealed a uniform surface morphology of the CuO-zeolite *** UV–vis spectrum of NCs showed absorption peaks between 230 and 280 nm for nano-CuO in the XRD patterns, and new peaks appeared between（36.56？–38.83？） related to the CuO. At weight ratio less than 10 wt%, the CuO nanoparticles loaded to the zeolite exhibited spherical shapes with average particle diameter of 6.5 nm measured by TEM and XRD. Antibacterial activities were tested against Gram-negative and Gram-positive bacteria. The obtained results showed that, CuO-zeolite NCs with 8 wt% CuO nanoparticles had the highest antibacterial activities against Bacillus Subtilis B29 and Salmonella Choleraesuis ATCC10708, which can be attributed to the good dispersion of CuO NPs on the zeolite surface.

关键词： Copper oxide-zeolite Nanocomposites Antibacterial

Influence of Internal Stresses in Few-Mode Fiber on the Thermal Characteristics of Regenerated Gratings

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Photonic Sensors 2019年第2期9卷 162-169页

作者： nurul Asha mohd NAZAL Kok Sing LIM Yen Sian LEE Muhammad Aizi MAT SALIM Harith AHMAD Photonics Research Centre University of Malaya Kuala Lumpur 50603 Malaysia Laser Center Ibnu Sina Institute for Scientific and Industrial Research Universiti Teknologi MalaysiaJohor Bahru 81310Malaysia

The pre-treatment of few-mode fibers (FMFs) has been successfully done with CO2 laser The wavelength difference, AA between the two resonant wavelengths in the few-mode fiber Bragg grating (FMFBG) varies with temperature increment during the annealing process. The results show that the treated fibers with lower stresses have lower thermal sensitivity in △λ than that of non-treated fiber. However, the treated fibers produce FMFBGs with better thermal durability and regeneration ratio. It is conceived that the presence of those stresses in the pristine fiber is responsible for the high thermal sensitivity in △λ. The thennal relaxation of stresses and structural rearrangement during the thennal annealing process are responsible for the degradation of the strength and resilience of the regenerated grating.

关键词： Regenerated fiber Bragg grating few-mode fiber thermal stress relaxation CO2 laser annealing thennal resilience

Composition of carbohydrates, surfactants, major elements and anions in PM2.5 during the 2013 Southeast Asia high pollution episode in Malaysia

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Particuology 2018年第2期16卷 119-126页

作者： Shoffian Amin Jaafar mohd Talib Latif Intan Suraya Razak nurul Bahiyah Abd Wahid Md Firoz Khan Thunwadee Srithawirat School of Environmental and Natural Resource Sciences Faculty of Science and Technology Universiti Kebangsaan Malaysia 43600 Bangi Selangor Malaysia Institute for Environment and Development (Lestari) Universiti Kebangsaan Malaysia 43600 Bangi Selangor Malaysia Department of Biology Faculty of Science and Mathematics Universiti Pendidikan Sultan ldris 35900 Tanjung Malim Perak Malaysia Centre for Tropical Climate Change System (IKLIM) Institute of Climate Change Universiti Kebangsaan Malaysia 43600 Bangi Selangor Malaysia Department of Environmental Science Faculty of Science and Technology Pibulsongkram Rajabhat University Phitsanulok Thailand

Haze episodes have become a major concern in Malaysia over the past few decades and have an increasingly important impact on the country each and every year. During haze episodes from biomass burning in Southeast Asia, particularly from Sumatra, Indonesia, particulate matter PM2.5 is found to be one of the dangerous sources of airborne pollution and is known to seriously affect human health. This study determines the composition of carbohydrates （as levoglucosan）, surfactants, major elements, and anions in PM2.5 during a 2013 haze episode. PM2.5 samples were collected from Universiti Kebangsaan Malaysia, Bangi, using a high volume sampler during a seven-day monitoring campaign during the peak of that year＇s haze episode. PM2.5 concentrations ranged between 14.52 and 160.93 μg/m3, exceeding the 2005 WHO air quality guidelines for PM2.5 （25 μg/m3 for 24-h mean）. The patterns for levoglucosan, surfactants, major elements, and anionic compositions were proportional to the PM2.5 concentrations. Changes in PM2.5 observed on days 3 and 4 were influenced by a combination of meteorological factors, which substantiate the theory that such factors play a pivotal role in haze episodes.

关键词： Aerosol Biomass burning Levoglucosan Surfactant Haze Inorganic composition