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Molecular Mechanism of the Specificity of Protein Import into Chloroplasts and Mitochondria in Plant Cells

Molecular Plant 2019年第7期12卷 951-966页

作者： Dong Wook Lee Sumin Lee Junho Lee Seungjin Woo Md.Abdur Razzak Alessandro Vitale Inhwan Hwang Division of Integrative Biosciences and Biotechnology Pohang University of Science and Technology Pohang 37673 Korea Department of Life Sciences Pohang University of Science and Technology Pohang 37673 Korea Istituto di Biologia e Biotecnologia Agraria Consiglio Nazionale Delle Ricerche Milano Italy

Plants possess both types of endosymbiotic organelles, chloroplasts and mitochondria. Transit peptides and presequences function as signal sequences for specific import into chloroplasts and mitochondria, respectively. However, how these highly similar signal sequences confer the protein import specificity remains elusive. Here, we show that mitochondrial- or chloroplast-specific import involves two distinct steps, specificity determination and translocation across envelopes, which are mediated by the N-terminal regions and functionally interchangeable C-terminal regions, respectively, of transit peptides and presequences. A domain harboring multiple-arginine and hydrophobic sequence motifs in the N-terminal regions of presequences was identified as the mitochondrial specificity factor. The presence of this domain and the absence of arginine residues in the N-terminal regions of otherwise common targeting signals confers specificity of protein import into mitochondria and chloroplasts, respectively. AtToc159, a chloroplast import receptor, also contributes to determining chloroplast import specificity. We propose that common ancestral sequences were functionalized into mitochondrial- and chloroplast-specific signal sequences by the presence and absence, respectively, of multiple-arginine and hydrophobic sequence motifs in the N-terminal region.

关键词： transit peptide presequence protein import into chloroplasts and mitochondria N-terminal specificity domain C-terminal common translocation domain import specificity determination

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基于聚多巴胺的碳纤维表面改性及其对环氧复合材料界面粘结性能的影响

基于聚多巴胺的碳纤维表面改性及其对环氧复合材料界面粘结性能的...

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作者： abdur razzak 陕西科技大学

学位级别：硕士

碳纤维增强复合材料日益普及。然而,提高这些复合材料的界面性能是目前的关键问题。碳纤维表面改性在改善碳纤维增强复合材料的界面性能方面起着至关重要的作用。纤维与基体之间的附着力决定了碳纤维增强复合层压板的性能,而粘合水平则... 详细信息

碳纤维增强复合材料日益普及。然而,提高这些复合材料的界面性能是目前的关键问题。碳纤维表面改性在改善碳纤维增强复合材料的界面性能方面起着至关重要的作用。纤维与基体之间的附着力决定了碳纤维增强复合层压板的性能,而粘合水平则取决于碳纤维的表面性能,因此必须对碳纤维的表面进行改性处理。本论文采用简单的浸渍涂覆工艺,利用聚多巴胺(PDA)生物聚合物涂层对碳纤维表面进行改性处理。采用扫描电子显微镜(SEM)、原子力显微镜(AFM)、显微共聚焦激光拉曼光谱仪和X射线光电子能谱(XPS)对表面形貌、粗糙度、结构和化学元素进行了检测。纤维的润湿性使用动态接触角仪(DCAT)测定的。使用热重(TGA)分析来确定PDA接枝量。使用电位分析仪测定PDA颗粒的大小。在界面测试仪上,采用微脱黏法评估界面粘附性能。根据实验结果,聚多巴胺(PDA)颗粒均匀地遍布碳纤维表面。与未经处理的纤维相比,多巴胺的最佳添加量为0.3 g,此时复合材料的IFSS性能提升了 52.6%,因为更多极性基团和更粗糙表面的协同作用大大增强了环氧树脂的润湿性。同时,在碳纤维表面被引入了一定的活性官能团和石墨状结构,大大提高了碳纤维的界面粘附能力。采用一种简单、绿色和有效的浸渍涂层方法,在碳纤维表面引入氧化铁簇,通过应用氯化铁(Ⅲ)基聚多巴胺络合物,以进一步提高其界面剪切强度(IFSS)。根据“XPS、FT-IR和UV-Vis光谱”的测试结果表明,Fe-O团簇沉积在纤维表面。通过复合材料界面评估装置测量,氯化铁(Ⅲ)对PDA颗粒的修饰以及CF和环氧树脂之间的界面附着力的提升是显著的。研究结果表明,与未经改性CF相比,改性后的碳纤维和环氧树脂之间的最大界面附着力增加68.6%,这意味着复合材料将具有更好的性能。

关键词：碳纤维表面改性界面附着力碳纤维增强复合材料聚多巴胺氯化铁(Ⅲ)

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Enhancement of the Sensitivity of Gas Sensor Based on Microstructure Optical Fiber

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Photonic Sensors 2015年第4期5卷 312-320页

作者： Monir MORSHED md. Imran HASAN S. M. abdur razzak Department of lnformation and Communication Technology Mawlana Bhashani Science and Technology University Tangail-1902 Bangladesh Department of Electronics & Telecommunication Engineering Rajshahi University of Engineering & Technology Rajshahi-6204 Bangladesh Department of Electrical & Electronic Engineering Rajshahi University of Engineering & Technology Rajshahi-6204 Bangladesh

这份报纸建议微观结构的设计和描述为察觉到应用的气体的光纤维。目的是在盖住 0.80 的一个宽传播乐队上检测有毒。

关键词：传感器灵敏度微结构光纤甲烷气体相对灵敏度光子晶体光纤气孔直径非圆形孔传输频带

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An Enhanced Hybrid Model Based on CNN and BiLSTMfor Identifying Individuals via Handwriting Analysis

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1689-1710页

作者： md.abdur Rahim Fahmid Al Farid Abu Saleh Musa Miah Arpa Kar Puza md.Nur Alam md.Najmul Hossain Sarina Mansor Hezerul Abdul Karim Department of Computer Science and Engineering Pabna University of Science and TechnologyPabna6600Bangladesh Faculty of Engineering Multimedia UniversityCyberjaya63100Malaysia Department of Computer Science and Engineering Bangladesh Army University of Science and TechnologySaidpur5311Bangladesh Department of Mathematics Pabna University of Science and TechnologyPabna6600Bangladesh Department of Electrical Electronic and Communication EngineeringPabnaUniversity of Science and TechnologyPabna6600Bangladesh Department of Electrical and Communication Engineering Pabna University of Science and TechnologyPabna6600Bangladesh

Handwriting is a unique and significant human feature that distinguishes them from one another.There are many researchers have endeavored to develop writing recognition systems utilizing specific signatures or symbols for person identification through verification.However,such systems are susceptible to forgery,posing security risks.In response to these challenges,we propose an innovative hybrid technique for individual identification based on independent handwriting,eliminating the reliance on specific signatures or symbols.In response to these challenges,we propose an innovative hybrid technique for individual identification based on independent handwriting,eliminating the reliance on specific signatures or symbols.Our innovative method is intricately designed,encompassing five distinct phases:data collection,preprocessing,feature extraction,significant feature selection,and classification.One key advancement lies in the creation of a novel dataset specifically tailored for Bengali handwriting(BHW),setting the foundation for our comprehensive approach.Post-preprocessing,we embarked on an exhaustive feature extraction process,encompassing integration with kinematic,statistical,spatial,and composite features.This meticulous amalgamation resulted in a robust set of 91 features.To enhance the efficiency of our system,we employed an analysis of variance(ANOVA)F test and mutual information scores approach,meticulously selecting the most pertinent features.In the identification phase,we harnessed the power of cutting-edge deep learning models,notably the Convolutional Neural Network(CNN)and Bidirectional Long Short-Term Memory(BiLSTM).These models underwent rigorous training and testing to accurately discern individuals based on their handwriting characteristics.Moreover,our methodology introduces a groundbreaking hybrid model that synergizes CNN and BiLSTM,capitalizing on fine motor features for enhanced individual classifications.Crucially,our experimental results underscore the superiority of our approach.The CNN,B

关键词： Bengali handwriting(BHW) person identification convolutional neural network(CNN) BiLSTM

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Geochemistry of subsurface Late Quaternary ironstones in Rajshahi and Bogra Districts, Bangladesh: implications for genetic and depositional conditions

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Acta Geochimica 2019年第3期38卷 404-413页

作者： md.Sazzadur Rahman Ismail Hossain Pradip Kumar Biswas md.abdur Rahim A.S.M.Mehedi Hasan md.Ibrahim Adham Department of Geology and Mining University of Rajshahi Institutes of Mining Mineralogy and Metallurgy (IMMM)BCSIR Department of Disaster Resilience and Engineering Patuakhali Science and Technology University

The present study deals with the geochemistry of Late Quaternary ironstones in the subsurface in Rajshahi and Bogra districts, Bangladesh with the lithological study of the boreholes sediments. Major lithofacies of the studied boreholes are clay, silty clay, sandy clay, fine to coarse grained sand, gravels and sands with(fragmentary) ironstones. The ironstones contain major oxides, Fe_2 O_3*(*total Fe)(avg. 66.6 wt%), SiO_2(avg. 15.3 wt%), Al_2 O_3(avg. 4.0 wt%), MnO(avg. 7.7 wt%), and CaO(avg. 3.4 wt%). These geochemical data imply that the higher percentage of Fe_2 O_3* along with Al_2 O_3 and MnO indicate the ironstone as goethite and siderite, which is also validated by XRD data. A comparatively higher percentage of SiO_2 indicates the presence of relative amounts of clastic quartz and manganese-rich silicate or clay in these rocks. These ironstones also have significant amounts of MnO(avg. 7.7 wt%) suggesting their depositional environments under oxygenated condition. Chemical data of these ironstones suggest that the source rock suffered deep chemical weathering and iron was mostly carried in association with the clay fraction and organic matter. Iron concretion was mostly formed by bacterial build up in swamps and marshes, and was subsequently embedded in clayey mud.Within the coastal environments, the water table fluctuates and goethite and siderite with mud and quartz became dry and compacted to form ironstone.

关键词： Ironstone Geochemistry Goethite Siderite Bangladesh

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Sources of Nitrogen in Combination with Systems of Irrigation Influence the Productivity of Modern Rice(Oryza sativa L.)Cultivars during Dry Season in Sub-Tropical Environment

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Phyton-International Journal of Experimental Botany 2022年第8期91卷 1687-1708页

作者： Uttam Kumer Sarker md.Romij Uddin Ahmed Khairul Hasan md.abdur Rahman Sarkar md.Abdus Salam md.Alamgir Hossain Eldessoky S.Dessoky Ismail A.Ismail Department of Agronomy Bangladesh Agricultural UniversityMymensingh2202Bangladesh Department of Crop Botany Bangladesh Agricultural UniversityMymensingh2202Bangladesh Department of Biology College of ScienceTaif UniversityTaif21944Saudi Arabia

In irrigated agricultural systems,nitrogen(N)and water are the vital resources for sustainability of the crop production in the modern era of climate change.The current study aimed to assess the impact of water and N management on the productivity of irrigated rice cultivars.In the context,a field observation was done at the research farm of Bangladesh Agricultural University,Mymensingh,during dry seasons in consecutive two years(2018–2019 and 2019–2020).The experiments were set up following split-plot design assigning water management in the main plots,nitrogen management in the sub-plots,and the cultivars were approved in the split-split plot with three replications.After two years observation,it was revealed that rice cultivar Binadhan-8 gave the maximum value of leaf area index,number effective tillers hill-1 and grains panicle-1 which lead to the higher grain yield(GY).Substantial relationships were observed among the concentration of N,growth,total dry matter(TDM)and N content,N uptake,N utilization effectiveness,and GY.However,with little exception,the Combined effect of water and N,cultivars and water management were varied significantly for all parameters.Finally,the results of the current study concluded that application of irrigation at 8 days after the disappearance of ponded water and source of 105 kg N ha-1 from PU+Poultry manure are the best management approach for the excellent performance of rice cultivar Binadhan-8.

关键词： Growth stage high yielding rice cultivar internal N use efficiency water productivity

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Visible light communication for intelligent transportation systems:A review of the latest technologies

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第4期8卷 483-492页

作者： Khaled Shaaban md Hosne Mobarok Shamim Khadija abdur-Rouf Department of Engineering Utah Valley UniversityOremUT 84058United States Department of Electrical and Computer Engineering McGill UniversityMontréalQC H3A 0E9Canada Department of Civil&Architectural Engineering Qatar UniversityDohaQatar

In seeking to improve traffic congestion and safety on roads and highways,there has been an increased interest in intelligent transportation systems(ITS).The emerging visible light communication(VLC)technology is a new candidate to enable wireless access in ITS.The purpose of this study is to present a comprehensive review of the current studies related to VLC.Since VLC facilitates illumination and data communication simultaneously,it reduces energy consumption significantly.Additionally,VLC is immune to electromagnetic interference,provides high data security,and utilizes unregulated visible light spectrum,showing promise as a potentially cheaper alternative to existing radio frequency(RF)based technology.Moreover,recent advances in semiconductor materials and solid-state technologies have enabled the development of efficient light-emitting diodes(LEDs)and laser diodes(LDs)which are used as transmitters in a VLC system.Although 10 s of Gbits/s data rate has been demonstrated in indoor VLC links,successful implementation of it in outdoor environments requires further research to overcome the challenges presented by environmental factors,unwanted lights,non-line of sight communication,directional radiation pattern,frequent fragmentation,and so on.Besides,in recent years,semiconductor LDs have been garnering more attention since they can transmit more data over longer distances due to their high quantum efficiency and modulation bandwidth compared to LEDs.As a result,urban planners,policy-makers,transportation engineers,and vehicle manufacturers are considering LD-based VLC to facilitate vehicle-to-vehicle and vehicle-to-infrastructure communication.Thus,this paper reviews and compares the most recent developments in VLC technologies,identifies their benefits and potential use in ITS applications,discusses the probable barriers for their implementation in our existing transportation infrastructure,and suggests future research directions and recommendations to overcome these challenges.

关键词： Vehicle-to-vehicle(V2V)communication Vehicle-to-infrastructure(V2I) communication Light-emitting diodes Laser diodes Internet of things Transportation network

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Investigation of Structural and Electronic Properties of [Tris(Benzene-1,2-Dithiolato)M]<sup>3-</sup>(M = V, Cr, Mn, Fe and Co) Complexes: A Spectroscopic and Density Functional Theoretical Study

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Advances in Chemical Engineering and Science 2019年第4期9卷 317-332页

作者： Mohammad A.Matin md.abdur Rahman Centre for Advanced Research in Sciences(CARS) Dhaka UniversityDhakaBangladesh

In this study, the first raw transition metals from V to Co complexes with benzene-1,2-dithiolate (L2-) ligand have been studied theoretically to elucidate the geometry, electronic structure and spectroscopic properties of the complexes. Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) methods have been used. The ground state geometries, binding energies, spectral properties (UV-vis), frontier molecular orbitals (FMOs) analysis, charge analysis and natural bond orbital (NBO) have been investigated. The geometrical parameters are in good agreement with the available experimental data. The metal-ligand binding energies are 1 order of magnitude larger than the physisorption energy of a benzene-1, 2-dthiolate molecule on a metallic surface. The electronic structures of the first raw transition metal series from V to Co have been elucidated by UV-vis spectroscopic using DFT calculations. In accordance with experiment the calculated electronic spectra of these tris complexes show bands at 522, 565, 559, 546 and 863 nm for V3+, Cr3+, Mn3+, Fe3+ and Co3+ respectively which are mainly attributed to ligand to metal charge transfer (LMCT) transitions. The electronic properties analysis shows that the highest occupied molecular orbital (HOMO) is mainly centered on metal coordinated sulfur atoms whereas the lowest unoccupied molecular orbital (LUMO) is mainly located on the metal surface. From calculation of intramolecular interactions and electron delocalization by natural bond orbital (NBO) analysis, the stability of the complexes was estimated. The NBO results showed significant charge transfer from sulfur to central metal ions in the complexes, as well as to the benzene. The calculated charges on metal ions are also reported at various charge schemes. The calculations show encouraging agreement with the available experimental data.

关键词： Transition Metal Time Dependent Density Functional Theory (TD-DFT) Binding Energy Spectroscopy Electronic Properties Tris(Benzene-1 2-Dithiolato) Coordination Complex

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AI-based small arms firing skill evaluation system in the military domain

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Defence Technology（防务技术） 2023年第11期29卷 164-180页

作者： Rezoanul Hafiz Chandan Nusrat Sharmin Muhaimin Bin Munir abdur razzak Tanvir Ahamad Naim Tasneem Mubashshira Mokhlesur Rahman Department of Computer Science and Engineering Military Institute of Science and TechnologyDhakaBangladesh

Evaluation system of small arms firing has an important effect in the context of military domain. A partially automated evaluation system has been conducted and performed at the ground level. Automation of such system with the inclusion of artificial intelligence is a much required process. This papers puts focus on designing and developing an AI-based small arms firing evaluation systems in the context of military environment. Initially image processing techniques are used to calculate the target firing score. Additionally, firing errors during the shooting have also been detected using a machine learning algorithm. However, consistency in firing requires an abundance of practice and updated analysis of the previous results. Accuracy and precision are the basic requirements of a good shooter. To test the shooting skill of combatants, firing practices are held by the military personnel at frequent intervals that include 'grouping' and 'shoot to hit' scores. Shortage of skilled personnel and lack of personal interest leads to an inefficient evaluation of the firing standard of a firer. This paper introduces a system that will automatically be able to fetch the target data and evaluate the standard based on the fuzzy systems.Moreover it will be able to predict the shooter performance based on linear regression techniques.Thereby, it compares with recognized patterns to analyze the individual expertise and suggest improvements based on previous values. The paper is developed on a Small Arms Firing Skill Evaluation System, which makes the whole process of firing and target evaluation faster with better accuracy. The experiment has been conducted on real-time scenarios considering the military field and shows a promising result to evaluate the system automatically.

关键词： Machine learning Processing Firing system Artificial intelligence

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Current scenario and challenges of plastic pollution in Bangladesh:a focus on farmlands and terrestrial ecosystems

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Frontiers of Environmental Science & Engineering 2023年第6期17卷 1-22页

作者： mdRaihanul Islam Sumaiya Akter Ruponti mdabdur Rakib Huy Quoc Nguyen Monjur Mourshed Faculty of Agriculture Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur 1706Bangladesh Department of Microbiology Faculty of Biological Science and TechnologyJashore University of Science of TechnologyJashore 7408Bangladesh Faculty of Heat and Refrigeration Engineering The University of Danang—University of Science and TechnologyDanang 550000Vietnam Mechanical and Automotive Engineering School of EngineeringRMIT UniversityBundooraVictoria 3083Australia Department of Mechanical Engineering Rajshahi University of Engineering and Technology(RUET)Rajshahi 6204Bangladesh

Plastic is considered one of the most indispensable commodities in our daily life.At the end of life,the huge ever-growing pile of plastic waste(PW)causes serious concerns for our environment,including agricultural farmlands,groundwater quality,marine and land ecosystems,food toxicity and human health hazards.Lack of proper infrastructure,financial backup,and technological advancement turn this hazardous waste plastic management into a serious threat to developing countries,especially for Bangladesh.A comprehensive review of PW generation and its consequences on environment in both global and Bangladesh contexts is presented.The dispersion routes of PW from different sources in different forms(microplastic,macroplastic,nanoplastic)and its adverse effect on agriculture,marine life and terrestrial ecosystems are illustrated in this work.The key challenges to mitigate PW pollution and tackle down the climate change issue is discussed in this work.Moreover,way forward toward the design and implementation of proper PW management strategies are highlighted in this study.

关键词： Plastic waste Farmlands Terrestrial ecosystem Marine life

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