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Frontiers of Optoelectronics 2017年第4期10卷 370-377页

作者： sakhawat hussain Tasnim ZERIN Md. Ashik KHAN Department of Electrical and Electronic Engineering University of Dhaka Dhaka-1000 Bangladesh

This study considered the design of an efficient, high brightness polar InGaN/GaN light emitting diode （LED） structure with A1GaN capping layer for green light emission. The deposition of high In （〉 15%） composition within InGaN quantum well （QW） has limitations when providing intense green light. To design an effective model for a highly efficient InGaN green LEDs, this study considered the compositions of indium and aluminum for InxGal xN QW and AlyGal yN cap layers, along with different layer thicknesses of well, barrier and cap. These structural properties significantly affect different properties. For example, these properties affect electric fields of layers, polarization, overall elastic stress energy and lattice parameter of the structure, emission wavelength, and intensity of the emitted light. Three models with different composition and layer thicknesses are simulated and analyzed to obtain green light with in-plane equilibrium lattice parameter close to GaN （3.189 A ） with the highest oscillator strength values. A structure model is obtained with an oscillator strength value of 1.18 × 10-1 and least in-plane equilibrium lattice constant of 3.218 A. This emitter can emit at a wavelength of 540 nm, which is the expected design for the fabrication of highly efficient, bright green LEDs.

关键词： green light emitting diode (LED) latticeparameter oscillator strength InGaN quantum well (QW),A1GaN capping layer

Improvement of thermally grown oxide layer in thermal barrier coating systems with nano alumina as third layer

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Transactions of Nonferrous Metals Society of China 2013年第5期23卷 1322-1333页

作者： Mohammadreza DAROONPARVAR Muhamad Azizi Mat YAJID Noordin Mohd YUSOF Saeed FAR AHANY Mohammad sakhawat hussain Hamid Reza BAKHSHESHIRAD Z.VALEFI Ahmad ABDOLAHI Department of Materials Manufacturing and Industrial EngineeringFaculty of Mechanical EngineeringUniversiti Teknologi Malaysia School of Metallurgy and Materials College of EngineeringUniversity of Tehran

A thermally grown oxide （TGO） layer is formed at the interface of bond coat/top coat. The TGO growth during thermal exposure in air plays an important role in the spallation of the ceramic layer from the bond coat. High temperature oxidation resistance of four types of atmospheric plasma sprayed TBCs was investigated. These coatings were oxidized at 1000 °C for 24, 48 and 120 h in a normal electric furnace under air atmosphere. Microstructural characterization showed that the growth of the TGO layer in nano NiCrAlY/YSZ/nano Al2O3 coating is much lower than in other coatings. Moreover, EDS and XRD analyses revealed the formation of Ni（Cr,Al）2O4 mixed oxides （as spinel） and NiO onto the Al2O3 （TGO） layer. The formation of detrimental mixed oxides （spinels） on the Al2O3 （TGO） layer of nano NiCrAlY/YSZ/nano Al2O3 coating is much lower compared to that of other coatings after 120 h of high temperature oxidation at 1000 °C.

关键词： high temperature oxidation nano thermal barrier coatings TGO layer spinels

Energy Fluctuation of Ideal Fermi Gas Trapped under Generic Power Law Potential U=Σ_(i=1)~d c_i|x_i/a_i|^(n_i) in d Dimensions

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Communications in Theoretical Physics 2016年第4期65卷 465-468页

作者： Mir Mehedi Faruk Md.Muktadir Rahman Dwaipayan Debnath Md.sakhawat Hossain Himel Theoretical Physics Blackett LaboratoryImperial College Department of Theoretical Physics University of Dhaka Department of Biomedical Physics and Technology University of Dhaka

Energy fluctuation of ideal Fermi gas trapped under generic power law potential U=Σ_(i=1)~d c_i|x_i/a_i|^(n_i) has been calculated in arbitrary *** fluctuation is scrutinized further in the degenerate limit μ>>K_B T with the help of Sommerfeld *** dependence of energy fluctuation on dimensionality and power law potential is studied in *** importantly our general result can not only exactly reproduce the recently published result regarding free and harmonically trapped ideal Fermi gas in d =3 but also can describe the outcome for any power law potential in arbitrary dimension.

关键词： Fermi gas power law potential energy fluctuation

Incorporating the mutational landscape of SARS-COV-2 variants and case-dependent vaccination rates into epidemic models

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Infectious Disease Modelling 2022年第2期7卷 75-82页

作者： Mohammad Mihrab Chowdhury Md Rafiul Islam Md sakhawat Hossain Nusrat Tabassum Angela Peace Department of Mathematics and Statistics Texas Tech UniversityLubbockTXUSA Department of Mathematics Iowa State UniversityAmesIAUSA

Coronavirus Disease(COVID-19),which began as a small outbreak in Wuhan,China,in December 2019,became a global pandemic within months due to its high *** the absence of pharmaceutical treatment,various non-pharmaceutical interventions(NPIs)to contain the spread of COVID-19 brought the entire world to a *** almost a year of seemingly returning to normalcy with the world's quickest vaccine development,the emergence of more infectious and vaccine resistant coronavirus variants is bringing the situation back to where it was a year *** the light of this new situation,we conducted a study to portray the possible scenarios based on the three key factors:impact of interventions(pharmaceutical and NPIs),vaccination rate,and vaccine *** our study,we assessed two of the most crucial factors,transmissibility and vaccination rate,in order to reduce the spreading of COVID-19 in a simple but effective *** order to incorporate the time-varying mutational landscape of COVID-19 variants,we estimated a weighted transmissibility composed of the proportion of existing strains that naturally vary over ***,we consider time varying vaccination rates based on the number of daily new *** method for calculating the vaccination rate from past active cases is an effective approach in forecasting probable future scenarios as it actively tracks people's attitudes toward immunization as active case *** simulations show that if a large number of individuals cannot be vaccinated by ensuring high efficacy in a short period of time,adopting NPIs is the best approach to manage disease transmission with the emergence of new vaccine breakthrough and more infectious variants.

关键词： Break-through variants Waning immunity Reinfection Non-pharmaceutical interventions(NPIs) Vaccination rate

二烯丙基三硫醚对麦蛾几丁质结构化学及其合成酶A的影响

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二烯丙基三硫醚对麦蛾几丁质结构化学及其合成酶A的影响

作者： sakhawat Shah 华中农业大学

学位级别：硕士

麦蛾是世界上危害较严重的储粮害虫之一,主要危害小麦,水稻和玉米。尽管当前的广谱性杀虫剂对于储粮害虫的防治效果较好,但因其不合理的使用,导致害虫抗药性、环境污染、危害人类健康以及气候变化等问题发生严重。因此,寻求一种可替代... 详细信息

麦蛾是世界上危害较严重的储粮害虫之一,主要危害小麦,水稻和玉米。尽管当前的广谱性杀虫剂对于储粮害虫的防治效果较好,但因其不合理的使用,导致害虫抗药性、环境污染、危害人类健康以及气候变化等问题发生严重。因此,寻求一种可替代传统化学农药的产品非常迫切。前期研究我们发现,大蒜精油主要活性物质—二烯丙基三硫醚(DAT)在亚致死浓度(LC=0.015μL/L)条件下,熏蒸处理麦蛾成虫,最终会降低其产卵量。同时,处理后的麦蛾转录组数据亦表明DAT也能降低几丁质合成酶基因A(CHSA)的表达。因此,为了深入了解麦蛾生殖与几丁质合成酶基因的关系,我们探究了DAT和CHSA基因对麦蛾成虫形态、生理和产卵的影响。同时,为了明确麦蛾几丁质类型,分析其化学构成元素、热稳定性、结晶度以及外观形态,本论文主要采用傅里叶变换红光光谱(FTIR),热重分析(TGA),X射线衍射(XRD),差示扫描量热法(DSC),和扫描电镜分析(SEM)等方法,检测和评估了DAT对麦蛾成虫几丁质的含量和化学结构的影响。主要结果如下:1)麦蛾几丁质合成酶基因(Scer CHSA)在成虫期体壁的表达量高于头部和脂肪体等组织;在亚致死浓度(LC=0.015μL/L)条件下,DAT熏蒸处理后会显著降低Scer CHSA基因表达并抑制其产卵量。同时,干扰Scer CHSA基因后,麦蛾的产卵量也显著下降,干扰组和对照组(注射GFP基因)的差异达极显著水平(P<0.001)。以上结果初步表明Scer CHSA基因可能具有调控麦蛾生殖能力的作用。2)组织切片结果表明,与对照组相比,DAT可引起麦蛾体壁结构的改变:体壁的排列混乱、硬度变薄且有明显的破损之处;表皮层显示不连续、皱缩和半透明状,且变薄的表皮层与皮细胞层有明显分层现象;内部脂肪体组织也被破坏。值得一提的是,干扰该基因后的组织切片结果与DAT处理组的结果类似。3)对照组雌雄虫的几丁质含量占每只成虫干重的18-20%,且雌雄虫间几丁质含量无显著差异;但DAT处理会显著下降雌雄虫的几丁质含量,与对照相比,其含量可降低8-10%(P<0.001)。4)麦蛾体壁的几丁质主要以a形式存在;借助傅里叶变换红光光谱(FTIR),热重分析(TGA),X射线衍射(XRD),差示扫描量热法(DSC)等方法,我们发现DAT处理麦蛾后会显著降低麦蛾几丁质的热稳定性和结晶度。总之,本研究结果表明DAT在亚致死浓度条件下(LC=0.015μL/L),能下调Scer CHSA基因的表达,引起表皮层几丁质含量下降和几丁质组织形态构造的改变,并最终抑制麦蛾的产卵。以上结果表明DAT作为一种友好的生物农药在害虫防治中具有巨大的应用潜力,为几丁质合成抑制剂替代品的研究奠定了基础。

关键词：麦蛾二烯丙基三硫醚几丁质合成酶A 几丁质产卵量下降生理形态学几丁质合成抑制剂

Insect(black soldier fly larvae) oil as a potential substitute for fish or soy oil in the fish meal-based diet of juvenile rainbow trout(Oncorhynchus mykiss)

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Animal Nutrition 2021年第4期7卷 1360-1370页

作者： Femi J.Fawole Shyam N.Labh Md sakhawat Hossain Ken Overturf Brian C.Small Thomas L.Welker Ronald W.Hardy Vikas Kumar Aquaculture Research Institute Department of AnimalVeterinary and Food SciencesUniversity of IdahoMoscowID83844USA Hagerman Fish Culture Experiment Station Aquaculture Research InstituteUniversity of IdahoHagermanIDUSA Department of Aquaculture and Fisheries University of IlorinIlorinNigeria Department of Aquaculture Faculty of FisheriesSylhet Agricultural UniversitySylhet3100Bangladesh United States Department of Agriculture Agricultural Research ServiceHagerman Fish Culture Experiment StationHagermanIDUSA

Alternative sources of fish oil(FO)are one of the major problems in aquaculture;therefore,the goal of the present study was to examine insect(black soldier fly larvae)oil(BSLO)as a potential replacer of fish/s oy oil in juvenile rainbow trout(initial average weight of 32±0.15 g)*** diets were formulated wherein FO(control diet)was completely replaced with either soybean oil(SO)or BSLO,and an additional BSLO-based diet supplemented with 1.5%bile acid(BSLO+BA)were fed to the fish for 10 *** performance of the BSLO fed group was similar(P>0.05)to that of the FO and SO fed groups,howeve r,the fish fed BSLO+BA diet registered the lowest growth(P0.05)affect the major nutrient content of whole-body,however,the fatty acid composition of the muscle and liver was influenced(P<0.05),with the highest 14:0,16:0,and total saturated fatty acid detected in BSLO or BSLO+BA fed trout compared to the others(P<0.001).No significant diffe rences were observed in eicosapentaenoic acid+docosahexaenoic acid(EPA+DHA)or total n-3 polyunsaturated fatty acid(PUFA)content in muscle among the groups,whereas,the highest EPA:DHA and n-3:n-6 ratios were detected in the FO *** expression for fatty acid binding protein(fabp),fatty acid synthase(fas),and△5 desaturase in the liver was lower in FO(P<0.05),while BSLO+BA registered the highest△6 expression(P=0.006).Supplementation of BA in the BSLO diet increased superoxide dismutase(SOD)and catalase(CAT)activities compared to the other groups(P<0.05).In conclusion,BSLO could serve as a substitute for FO and SO in rainbow trout diet without negatively impacting growth performance,whole-body composition and nutrient retention,and modulate the expression of fatty acid metabolism-related genes in rainbow trout.

关键词： Insect oil Rainbow trout Growth performance Fatty acid metabolism Antioxidant enzyme

Role of digestive protease enzymes and related genes in host plant adaptation of a polyphagous pest,Spodoptera frugiperda

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Insect Science 2021年第3期28卷 611-626页

作者： Muhammad Hafeez Xiao-Wei Li Jin-Ming Zhang Zhi-Jun Zhang Jun Huang Li-Kun Wang Muhammad Musa Khan sakhawat Shah G.Mandela Fernandez-Grandon Yao-Bin Lu State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Institute of Plant Protection and MicrobiologyZhejiang Academy of Agricultural SciencesHangzhou310021China Key Laboratory of Bio-Pesticide Innovation and Application Guangzhou510642China Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanHubei430070China Natural Resources Institute University of GreenwichChathamMaritimeKentME44TBUK

The evolutionary success of phytophagous insects depends on their ability toefficiently exploit plants as a source of energy for *** insects largelydepend on the efficiency,flexibility,and diversity of their digestive physiology and sophistication of their detoxification system to use chemically diverse host plants as *** fall armyworm,Spodoptera frugiperda(***),is a polyphagous pest ofmany commercially important *** elucidate the ability of this insect pest to adaptto host plant mechanisms,we evaluated the impact of primary(corn)and alternate(rice)host plants after 1l generations on gut digestive enzymatic activity and expression profiles of related *** indicated that the total protease and classspecific trypsinand chymotrypsinlike protease activity of *** significantly differed among hostplant *** classspecifiq protease profiles greatly differed in *** upon larval exposure to different treatments with inhibitors compared with treatments without ***,the single and cumulative effects of the enzymespecific inhibitors TLCK,TPCK,and E64 significantly increased larval mortality and reduced larval growth/mass across different plant ***,the quantitativereverse transcription polymerase chain reaction results revealed increased transcription oftwo trypsin(SfTry3,SfTry7)and one chymotrypsin gene(Sfchym9),which indicatedthat they have roles in host plant *** of these genes resulted in significantly reduced mRNA expression levels of the trypsin *** was related to theincreased mortality observed in treatments compared with the dsRED *** resultindicates possible roles of *** gut digestive enzymes and related genes in hostplant adaptation.

关键词： digestive enzymes gene expression host plant adaptation RNA interference Spodoptera frugiperda

Towards Mining Public Opinion: An Attention-Based Long Short Term Memory Network Using Transfer Learning

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Journal of Computer and Communications 2022年第6期10卷 112-131页

作者： G. M. sakhawat Hossain Md. Harun Or Rashid Md. Rafiqul Islam Ananya Sarker Must. Asma Yasmin Department of Computer Science and Engineering Rangamati Science and Technology University Rangamati Bangladesh Department of Computer Science and Engineering Bangladesh Army University of Engineering and Technology Qadirabad Bangla-desh

The Internet provides a large number of tools and resources, such as social media sites, online newsgroups, blogs, electronic forums, virtual communities, and online travel sites, for consumers to express their views or opinions regarding various issues. These opinions can help organizations like tourism to improve their products and services for their consumers. Opinion mining refers to a process of identifying emotions by applying Natural Language Processing (NLP) techniques to a pool of texts. This paper mainly focuses on mining public opinion from the hotel reviews domain. To do so, we proposed a novel technique called the Attention-Based Long Short Term Memory (Attention-LSTM) Network using a transfer learning approach. We empirically analyzed several machine learning and deep learning methods and observed our proposed technique provided an adequate performance for mining public opinion in the hotel reviews domain.

关键词： Opinion Mining Deep Learning Word2Vec Attention-LSTM Transfer Learning

DNA羟甲基化酶TET2突变对其功能的影响

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生命的化学 2017年第2期37卷 153-158页

作者：王申森马羚张丽娜 sakhawat Ali 刘亚茹汪涛黄映辉北京工业大学生命科学与生物工程学院北京100022

DNA羟甲基化是继DNA甲基化之后发现的又一重要的表观遗传修饰,在基因的表达调控、染色体重塑等方面有着重要功能。TET2(ten-eleven-translocation 2,TET2)基因作为调控DNA羟甲基化形成的TET家族蛋白的成员之一,能够催化5甲基胞嘧啶(5-me... 详细信息

DNA羟甲基化是继DNA甲基化之后发现的又一重要的表观遗传修饰,在基因的表达调控、染色体重塑等方面有着重要功能。TET2(ten-eleven-translocation 2,TET2)基因作为调控DNA羟甲基化形成的TET家族蛋白的成员之一,能够催化5甲基胞嘧啶(5-methyl-cytosine,5m C)形成5羟甲基胞嘧啶(5-hydroxymethyl-cytosine,5hm C),在表观遗传学中具有重要的地位。近年来,在骨髓增生性肿瘤(myeloproliferative neoplasms,MPN)、系统性肥大细胞增生症(systemic mastocytosis,SM)、慢性骨髓单核细胞性白血病(chronic myelomonocytic leukemia,CMML)和骨髓增生异常综合征(myelodysplastic syndrome,MDS)等疾病中均发现了TET2的突变,并影响了5m C和5hm C含量的变化。对TET2突变的研究仍是一个很新颖的课题,TET2在不同疾病中突变的位置和类型以及对其功能的影响尚处于探索研究之中。本文对各类疾病中发现的TET2突变及其功能的影响进行了综述,深入阐述了TET2的突变对拓展DNA去甲基化和寻找疾病新靶标具有的潜在应用价值。

关键词： DNA羟甲基化酶 TET2 突变功能

Element Composition of the Atmospheric Depositions in Bangladesh

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Journal of Environmental Protection 2018年第9期9卷 948-956页

作者： Jatish Chandra Biswas Md Mozammel Haque Mahmuda Akter A. T. M. sakhawat Hossain Faruk Hossain Khan Md Zakaria Ibne Baki Abu Bakar Siddique Sarker Md Rafiqul Islam Bangladesh Rice Research Institute Gazipur Bangladesh

Compositions of dry and wet atmospheric depositions vary depending on geographic locations and industrialization. Fog waters were collected from different regions of Bangladesh along with rain, sub-surface irrigation water and dust particles from Gazipur and compositions were analyzed. The compositions of fog water varied greatly among locations. The ammonium nitrogen (NH+4-N) content was the highest (36 - 37 ppm) in Gazipur district and the lowest in Sylhet district (3.2 - 3.6 ppm). Phosphorus (5.2 - 5.5 mg/L), K (29.5 - 30 mg/L), S (11.0 - 11.5 mg/L), Zn (2.9 - 3.3 mg/L), Na (11.7 - 12.5 mg/L), Ca (22.0 - 23.3 mg/L) and Cd (0.14 - 0.17 mg/L) contents were also higher in Gazipur district. Dust particles, rain and sub-surface irrigation water of Gazipur district contained considerable amounts of macro and micro elements. We conclude that dry and wet atmospheric depositions varied depending on locations and industrial development. Such study needs to be correlated with ecological consequences and soil fertility management.

关键词： Water Dust Chemical Composition Regions