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Optics and Photonics Journal 2014年第10期4卷 280-287页

作者： Md. Shahinul Islam Md. Golam Saklayen Md. Ferdous Rahman Hartmut Baerwolff abu bakar Md. Ismail Department of Applied Physics & Electronic Engineering Rajshahi University Rajshahi Bangladesh Department of Electronics and Telecommunication Engineering Begum Rokeya University Rangpur Bangladesh Department of Analog & Optoelectronics Cologne University of Applied Sciences Cologne Germany

This article presents the investigation on very thin Lanthanum Fluoride (LaF3) layer as a new cathode buffer layer (CBL) for organic solar cell (OSC). OSCs were fabricated with poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) polymer blend at 1:1 ratio. Electron-beam evaporation at room temperature was used to deposit 3 and 5 nm thick LaF3 layer. A very smooth surface of LaF3 with an average roughness of 0.2 nm has been observed by the Atomic Force Microscope (AFM) that is expected to prevent diffusion of cathode metal ion through it and thereby enhance the lifetime and stability of OSC. Huge enhancement of JSC and VOC was also observed for 3 nm-thick LaF3 CBL. Several excellent features of the LaF3 layer such as, transporting electron through tunneling, blocking of holes to the cathode, minimizing recombination, protecting the photoactive polymer from ambient oxygen, and reducing degradation/oxidation of any low work function layer at the cathode interface, might have contributed to the performance enhancement of OSC. The experimental findings indicate the promise of LaF3 to be an excellent CBL material for OSC.

关键词： Organic Semiconductor Photoactive Polymer Organic Solar Cell Bulk Heterojunction Solar Cells Cathode Buffer Layer Lanthanum Fluoride Spin Coating E-Beam Evaporation

Engineering catalytic efficiency of thermophilic lipase from <i>Geobacillus zalihae</i>by hydrophobic residue mutation near the catalytic pocket

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Advances in Bioscience and Biotechnology 2012年第2期3卷 158-167页

作者： Roswanira Abdul Wahab Mahiran Basri Mohd Basyaruddin Abdul Rahman Raja Noor Zaliha Raja Abdul Rahman abu bakar Salleh Leow Thean Chor 3Institute of Bioscience Universiti Putra Malaysia Serdang Malaysia 4Faculty of Biotechnology and Biomolecular Sciences Universiti Putra Malaysia Serdang Malaysia Faculty of Science Universiti Putra Malaysia Serdang Malaysia Faculty of Science Universiti Teknologi Malaysia Skudai Malaysia

In-silico and experimental investigations were conducted to explore the effects of substituting hydrophobic residues;Val, Met, Leu, Ile, Trp and Phe into the oxyanion Q114 of T1 lipase. We hypothesized that the oxyanion Q114, involved in substrate binding is also associated with modulation of conformational stability and in conferring specific enzyme attributes. The insilico investigations accurately predicted the quality of the protein packing in some of the variants. Our study found by altering the hydrophobicity of the oxyanion 114, remarkably altered enzyme conformational stability and catalytic attributes. Substitution with Leu resulted improvements in four out of the six tested characteristics. The hydrophobic Leu might have improved local structure folding and increased hydrophobic interactions with other residues in the vicinity of the mutation. The Met variant showed higher activity over the wild-type in hydrolyzing a wider range of natural oils. The bulky amino acids, Phe and Trp negatively affected T1 lipase and resulted in the largest disruption of protein stability and inferior enzyme characteristics. We have successfully illustrated that a single point residue changes at oxyanion 114 could result in a myriad of enzyme attributes, which implied there was some interplay between hydrophobicity and conformation for lipase catalytic functions.

关键词： Hydrophobic Residue T1 Lipase Oxyanion Conformational Stability Catalytic Pocket

Forkhead box P3 and indoleamine 2,3-dioxygenase co-expression in Pakistani triple negative breast cancer patients

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World Journal of Clinical Oncology 2020年第12期11卷 1018-1028页

作者： Kashif Asghar Asif Loya Iftikhar Ali Rana Muhammad abu bakar Asim Farooq Muhammad Tahseen Muhammad Ishaq Iqra Masood Muhammad Usman Rashid Department of Basic Science Research Shaukat Khanum Memorial Cancer Hospital and Research CentreLahorePunjab 54000Pakistan Department of Pathology Shaukat Khanum Memorial Cancer Hospital and Research CentreLahorePunjab 54000Pakistan Department of Cancer Registry and Clinical Data Management Shaukat Khanum Memorial Cancer Hospital and Research CentreLahorePunjab 54000Pakistan Department of Clinical Research Shaukat Khanum Memorial Cancer Hospital and Research CentreLahorePunjab 54000Pakistan

BACKGROUND Forkhead box P3(FOXP3)is a specific marker for immunosuppressive regulatory T(T-reg)cells.T-regs and an immunosuppressive enzyme,indoleamine 2,3-dioxygenase(IDO),are associated with advanced disease in *** To evaluate the co-expression of FOXP3 and IDO in triple negative breast cancer(TNBC)with respect to hormone-positive breast cancer patients from *** Immunohistochemistry was performed to analyze the expression of FOXP3,IDO,estrogen receptor,progesterone receptor,and human epidermal growth factor receptor on tissues of breast cancer patients(n=100):Hormone-positive breast cancer(n=51)and TNBC(n=49).A total of 100 patients were characterized as FOXP3 negative vs positive and further categorized based on low,medium,and high IDO expression *** and multivariate logistic regression models were *** Out of 100 breast tumors,25%expressed FOXP3 positive T-regs.A significant coexpression of FOXP3 and IDO was observed among patients with TNBC(P=0.01)compared to those with hormone-positive breast *** variables were identified as significant independent risk factors for FOXP3 positive:IDO expression high(adjusted odds ratio(AOR)5.90;95%confidence interval(CI):1.22-28.64;P=0.03)and TNBC(AOR 2.80;95%CI:0.96-7.95;P=0.05).CONCLUSION Our data showed that FOXP3 positive cells might be associated with high expression of IDO in TNBC ***3 and IDO co-expression may also suggest its involvement in disease,and evaluation of FOXP3 and IDO expression in TNBC patients may offer a new therapeutic option.

关键词： Forkhead box P3 Indoleamine 2,3-dioxygenase Triple negative breast cancer T-regs Immunotherapy Cancer

盘式制动器热传导、接触压力和瞬变振动的综合分析

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传动技术 2013年第2期27卷 29-37页

作者： Huajiang Ouyang Abd Rahim abu-bakar Lijie Li 介眉 University of Liverpool Department of Engineering University of Liverpool

本文采用瞬变分析法研究了汽车盘式制动器的尖叫声,并首次试图综合热传导分析、接触分析和盘式制动器尖叫声的瞬变分析,计算了盘和衬片的接合面上的接触压力,采用该数据确定了摩擦导致的热流,再进一步分析了热传导,最后考虑由于制动器... 详细信息

本文采用瞬变分析法研究了汽车盘式制动器的尖叫声,并首次试图综合热传导分析、接触分析和盘式制动器尖叫声的瞬变分析,计算了盘和衬片的接合面上的接触压力,采用该数据确定了摩擦导致的热流,再进一步分析了热传导,最后考虑由于制动器衬片表面的粗糙度和热变形对接触压力分布的作用,对发生尖叫声的影响进行瞬变分析。得出有热的的影响和没有热量影响的动态响应之间是明显不同的结果。

关键词：盘式制动器尖叫声热效应瞬变分析有限元有限元

An overview of freshwater prawn fishery in Bangladesh:present status and future prospect

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Journal of Coastal Life Medicine 2014年第7期 580-588页

作者： Ferdous Ahamed Bernerd Fulanda Muhammad abu bakar Siddik Md.Yeamin Hossain Md.Mostafizur Rahman Mondol Zoarder Faruque Ahmed Jun Ohtomi Department of Fisheries Management Patuakhali Science and Technology UniversityBangladesh Kenya Marine and Fisheries Research Institute Marine and CoastalP.O.Box 81651Mombasa 80100Kenya Department of Fisheries Biology and Genetics Patuakhali Science and Technology UniversityBangladesh Department of Fisheries Faculty of AgricultureUniversity of RajshahiRajshahi 6205Bangladesh Department of Fisheries Management Bangladesh Agricultural UniversityMymensingh 2202Bangladesh Faculty of Fisheries Kagoshima University4-50-20 ShimoarataKagoshima 890-0056Japan

The freshwater prawn fishery plays an important role in the economy of *** fishery is mainly based on the culture of Macrobrachium *** culture fishery has been growing rapidly,thus,masking the dwindling capture fishery which is faced with serious environmental issues augmented by deleterious fishing *** the high prospects of the freshwater prawn aquaculture in Bangladesh,a lot of research is needed to ensure the sustainable development of the capture fishery which forms a key source of prawn aquaculture seed as well as provide a baseline for future *** prawn aquaculture in Bangladesh is based on traditional methods with continuous adaptations by the rural ***,numerous constraints to its full development are evident at all stages of its *** of quality brood stock,seed,feeds and poor technical knowledge at farmers level are but some of the impediments challenging the sustainability of this *** paper reviews the freshwater prawn fishery of Bangladesh over the last few decades and outlines approaches for the development of an ecosystem-based management of both the culture and capture sectors of this important fishery.

关键词： Freshwater prawn fishery Aquaculture Economy Sustainable management Bangladesh

Descriptive Epidemiology of Multidrug Resistance Tuberculosis (MDR-TB) in Bangladesh

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Journal of Tuberculosis Research 2018年第4期6卷 292-301页

作者： abu bakar Siddik Muhammad Maqsud Hossain Sanjana Zaman Basana Marma Gias Uddin Ahsan Mohammad Rashed Uzzaman Arman Hossain Mohammad Delwer Hossain Hawlader School of Health and Life Sciences North South University Dhaka Bangladesh Genome Research Institute North South University Dhaka Bangladesh Department of Public Health North South University Dhaka Bangladesh Plan International Bangladesh Dhaka Bangladesh School of Business and Economics North South University Dhaka Bangladesh

Background: The number of reported MDR-TB cases has been increasing in recent years. Objectives: To describe the epidemiological profile of MDR-TB cases in Bangladesh. Design: This was a descriptive cross-sectional study. Settings: The study was conducted among the multi drug resistant tuberculosis patient admitted in the National Institute of Diseases of the Chest and Hospital (NIDCH) Dhaka, Bangladesh. Samples: 148 confirmed cases of MDR-TB. Materials and Methods: Hospital admitted MRD-TB cases were randomly chosen from the above mentioned hospital. Semi-structured and pretested questionnaire were introduced by researcher. Clinical and treatment data i.e. duration of TB drug intake, report of sputum, X-ray and blood test etc. were extracted from the hospital record. Results: Study found, majority of the participants (56.1%) were in the age group of 16 - 30 years. 64.2% of the study subjects were married. Majority of the participants education were whether under primary or primary level. 24.3% participant’s family member and 14.5% of neighbor were having TB. Most common comorbidity were diabetes, pulmonary infection, hearing loss, psychiatric symptoms, chest pain, joint pain etc. 63.5% respondent had high degree of AFB for sputum positivity and more than 98% had positive finding in X-ray chest. On an average ESR was low and also few cases of extremely low ESR were found. 71.6% were under twenty four months regimen. Conclusion: We can conclude that, many possible factors for MDR-TB. There is an urgent need for further study to confirm the exact factors in Bangladesh and address those immediately.

关键词： MDR-TB Risk Factors Descriptive Study Epidemiology Bangladesh

采用有限元法通过改进结构消除鼓式制动器噪声

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传动技术 2012年第4期26卷 32-41页

作者： Abd Rahim abu—bakar Mohd Reaza Buang Roslan Abdul Rahman Mohd Zam abu Rashid Universiti Teknologi Malaysia Universiti Teknologi Malaysia Johor. Universiti Teknologi Malaysia.

降低制动器噪声已成为制动器工程师们具有挑战性的任务。目前关于处理盘式制动器噪声方面已有许多建议,但过去在鼓式制动器系统方面解决方法很少。本文企图提出一种采用有限元方法通过改进结构,降低鼓式制动器噪声。开发并证实了一个真... 详细信息

降低制动器噪声已成为制动器工程师们具有挑战性的任务。目前关于处理盘式制动器噪声方面已有许多建议,但过去在鼓式制动器系统方面解决方法很少。本文企图提出一种采用有限元方法通过改进结构,降低鼓式制动器噪声。开发并证实了一个真实鼓式制动器的三维有限元(FE)模型。首先用模拟的基本有限元模型预测噪声,然后再提出几个改进结构,最后对选择的改进模型进行动态不稳定过程分析,以便确认由复杂的固有值分析得出的预测结果。

关键词：鼓式制动器有限元结构改进噪声复杂固有值不稳定过程分析

Sustainable Denim Washing by Process Optimization

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Journal of Textile Science and Technology 2022年第4期8卷 149-162页

作者： Md. abu bakar Siddiquee A. T. M. Gulam Moula Joy Krisna Saha Md. Humayun Kabir Khan Zihan Kaisar Abhijit Roy Department of Textile Engineering Mawlana Bhashani Science & Technology University Tangail Bangladesh Department of Fabrics Engineering Bangladesh University of Textiles Dhaka Bangladesh

Now-a-days sustainability is a crucial issue in denim washing. This research initiative is performed aiming to resolve the crisis of sustainability in denim washing by process optimization technique which highlights the reduction of water, chemical and time as well as costing of denim garments. In this research work, process optimization technique is administered by reducing several wash & chemical application baths into a single bath confirming without alteration of physical properties and color fastness of denim fabric. For confirmation without alteration of physical properties and color fastness, several tests are carried out like tensile and tear strength, color fastness to rubbing, color fastness to wash, color fastness to water, color fastness to perspiration and CMC (Carboxy Methyl Cellulose) value for both conventional and sustainable washing method. BOD, COD and pH of waste water is determined which shows better result in sustainable washing method also. Reduction of rinsing time in sustainable washing method results in less consumption of water by 475 and process time by 19% and also saves $0.34/ dozen garments which validate the cost effectiveness of this sustainable washing method.

关键词： Sustainability Denim Wash Color Fastness Cost Analysis

Determination of Malaysian Herbs and Spices as Biopreservative Agents in Food Products

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American Journal of Plant Sciences 2015年第5期6卷 718-724页

作者： Saripah Salbiah Syed Abdul Azziz Munirah Abdul Talip Chee Fah Wong Hasimah Alimon Norlaili abu bakar Wan Rusmawati Wan Mahamod Rozita Yahaya Mohamad Syahrizal Ahmad Yusnita Juahir Department of Chemistry Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tanjung Malim Perak Malaysia Department of Biology Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tanjung Malim Perak Malaysia

Preservatives are usually added to food products to ensure longer shelf life and prevent decomposition process and microbial growth. However, synthetic food preservatives can also give negative side effect to health and are harmful to human and animal physiology. Based on the potential of herbs and spices as antimicrobial agent, the purpose of this study is to identify antibacterial activity from extracts of some local herbs and spices: Phaeomeria speciosa (P. speciosa), Aquilaria subintegra (A. subintegra), Polygonum minus (P. minus), Syzygium aromaticum (S. aromaticum), Cinnamomum verum (C. verum) and Piper nigrum (P. nigrum) against food bacteria using disc diffusion method. Results revealed that dichloromethane extracts of C. verum, hexane extracts of S. aromaticum and P. minus showed the most active antibacterial against tested bacteria. The Minimal Inhibitory Concentrations (MIC) ranged from 25 to 75 mg/ml for dichloromethane extract of C. verum, hexane extract of S. aromaticum and P. minus. Therefore further research should be pursued to identify the chemical structure of antibacterial agents from the active extracts as an alternative source of natural preservatives.

关键词： Preservative Agents Antibacterial Activity Disc Diffusion Assay MIC

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