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Antidiabetic and antioxidant activities of Nypa fruticans Wurmb. vinegar sample from Malaysia

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Asian Pacific Journal of Tropical Medicine 2015年第8期8卷 589-597页

作者： Nor Adlin Yusoff Mun Fei Yam Hooi Kheng Beh Khairul Niza Abdul Razak Tri Widyawati Roziahanim mahmud Mariam Ahmad Mohd Zaini Asmawi School of Pharmaceutical Sciences Universiti Sains Malaysia Integrative Medicine Cluster Advanced Medical and Dental InstituteUniversiti Sains Malaysia Pharmacology Department Medical FacultyUniversity of Sumatera Utara

Objective: To study the antidiabetic and antioxidant activities of nipa palm vinegar(NPV) used in traditional Malay medicine for treating diabetes. Methods: NPV was extracted using liquid-liquid extraction method and the obtained samples were subjected to antidiabetic studies using normal and streptozotocin-induced diabetic rat models whereas antidoxidant activities were investigated via in vitro antioxidant tests namely 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis-3-ethylbenzothiozoline-6-sulfonic acid free radicals scavenging activities and the reducing power assay. Results: Single administration of NPV and its extracts were not effective in both normal and diabetic rats. In intraperitoneal glucose tolerance test, NPV and its aqueous extract showed significant blood glucose lowering effect. In the sub-acute study, compared with the diabetic control, aqueous extract of NPV showed the most notable blood glucose lowering effect(56.6%) and a significant improvement in serum insulin levels(79.8%, P<0.05). To assess NPV's antioxidant activity, three in vitro antioxidant tests were employed: 2,2-diphenyl-1-picryhydrazyl and 2,2'-azinobis-3-ethylbenzothiozoline-6-sulfonic acid free radical-scavenging assays, and the reducing power assay. Ethyl acetate extract had the greatest antioxidant potential and content of phenolic and flavonoid compounds. A linear positive correlation between the antioxidant parameters was observed. Chemical profiling analysis of aqueous extract of NPV revealed the presence of acetic acid(35.25%), the main active constituent which significantly contributed to the observed antidiabetic activity. Conclusions: Aqueous extract of NPV possesses antihyperglycaemic activities comparable to the metformin, while the ethyl acetate extract precipitated significant antioxidant effects attributable to its high phenolic content. These findings suggest that antioxidant compounds of NPV do not contribute much towards the overall observed antidiabetic effect.

关键词： Nypa fruticans Wurmb. Vinegar Antidiabetic Streptozotocin-induced diabetes Antioxidant Phenolics

Awareness about Early Detection Methods, Symptoms and Risk Factors towards Breast and Cervical Cancer among the Female Students of Mawlana Bhashani Science and Technology University (MBSTU), Santosh, Tangail, Bangladesh

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Advances in Breast Cancer Research 2017年第2期6卷 49-67页

作者： Fatama Tous Zohora Nibedita Paul Shahin mahmud S.M.Neaz mahmud Abu Zaffar Shibly Department of Biotechnology and Genetic Engineering Mawlana Bhashani Science and Technology UniversitySantoshBangladesh

The study was conducted to ensure knowledge, attitude, awareness about breast and cervical cancer among the female students of Mawlana Bhashani Science and Technology University. This study was carried out from July to September, 2015 among the participants of university female halls, different female hostels and different faculty of the university by using a validated questionnaire which was developed for this study. A total 250 female students, at the age of (18 - 26) years were participated. Collected information was analyzed using SPSS, Graph-pad Prism and MS Excel. The results showed that about 87.6% participants were undergraduate. Most of them come from village (45.6%) and city (36.0%). About 90% were Muslims and the socioeconomic level of most of the participants was middle (90.4%). In case of food intake patterns, it was observed that 35.6% participants eat chips, soft drinks, popcorn everyday;40.4% eat meat regularly;24% eat sugar everyday;27.6% eat fruits and vegetables every day. Among them, 55.6% girls maintained daily 1 hour physical activity;37.2% did exercise rarely;34.8% participants rarely do strenuous exercise. About 84.4% respondents have not any family history of cancer;6% participants have sister or mother having breast tumor and 7.2% have at least more than one close relative who have cancer. Among the participants, only 0.8% drank alcohol;1.2% have addiction of smoking cigarette;15.6% girls wear tight bra;3.6% have benign breast disease and 2.8% participants have attended in breast or cervical cancer screening programs. The moderate numbers of girls have breast cancer screening practice. Among them, only 28.8% participants have ever heard about BSE (Breast self-examination) and 40.4% have not any knowledge about breast cancer treatment. About 50.8% respondents don’t have any knowledge about cervical cancer treatment. The village people are the most risky group. About 17.02% girls recognized weakened immune system as a risk factor of cervical

关键词： Breast Cancer Cervical Cancer Risk Factors Symptoms Awareness Treatments

Analysis of Vehicle Modification Practice in Bangladesh

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Journal of Traffic and Transportation Engineering 2013年第1期1卷 9-18页

作者： Sakib mahmud Khan Md. Shamsul Hoque Glenn Department of Civil Engineering Clemson University Clemson 29634 USA Department of Civil Engineering Bangladesh University of Engineering and Technology Dhaka 1000 Bangladesh

With the shocking present vehicle growth over 10%, many vehicles are found to operate within urban areas and national highways of Bangladesh without having necessary registration and fitness papers. Uncontrolled vehicle modification practice has become a serious concern particularly for large vehicles, which leads the vehicle owners not to properly adhere to the vehicle fitness rules. The primary objective of this research is to reveal the extent of vehicle modification of different categories of vehicle. In this regard, field survey is conducted in major bus terminals and truck depots of Dhaka city to find out the issues related to rampant vehicle modification. Later statistical analysis is performed to obtain the most observed vehicle dimensions followed by local body workers. Finally, detailed questionnaire survey is performed on vehicle owners as well as the body makers as an attempt to reveal the poor quality of work performed by unskilled local workers. This paper would describe the findings of this research work along with appropriate remedial measures to control the unsafe modification of vehicles.

关键词： Vehicle modification vehicle fitness in-vehicle unsafe material body maker of Bangladesh.

Means-End Chain Model Framework for Measuring Housing Environment Choice Behavior

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Journal of Civil Engineering and Architecture 2011年第6期5卷 535-547页

作者： Zinas Bako Zachariah mahmud Bin Mohd Jusan Department of Architecture Universiti Teknologi Malaysia （UTM） Malaysia

Housing and housing space has been a place for personal development, recreation and self accentuation. The need for housing and housing space quality can therefore not be overemphasized. The need for housing remains a constant index for all societies through the ages. Housing is a complex and heterogeneous product in its setting, the cognitive structures of housing users for housing attributes is also complex as well as their choice behaviors. Means-End Chain （MEC） model has been found to be very effective and potent in measuring these complexities. This conceptual paper explores from literature the MEC model and attempts to propagate its use as a research model for housing research, environment-behavior studies and person-environment congruence. It also presents the methodology employed by MEC for data collection and data management. It will suggest an extension to the traditional methodology that MEC utilizes. The possibility of extending the previous methods and their applicability in design process is herein presented; and to make a case for the usability of MEC model as a research tool for housing researchers. In dealing with user preference of housing, there is a need for research for a development of a technological tool for the identification of user needs and preference, and the kind of decision support that are required to identify these needs.

关键词： Means-End Chain laddering technique housing preference and choice stated models revealed models.

A DSS for Human Resettlement: Supporting Interactive Optimal Decisions

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American Journal of Operations Research 2012年第3期2卷 322-330页

作者： Sajjad Zahir Ziaul Al-mahmud Ruhul Sarker Faculty of Management University of Lethbridge Lethbridge Alberta Canada School of Engineering & IT UNSW@ADFA Canberra Australia

Decisions regarding relocation of people due to environmental requirements can be very complex and may have serious socio-economic implications. We present the design of a Decision Support System to support such decis... 详细信息

关键词： Decision Support Systems Environmental Decision Goal Programming Model Analytic Hierarchy Process Integration Interactive Interface

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研究表面粗糙度对太赫兹回旋管开腔的影响

研究表面粗糙度对太赫兹回旋管开腔的影响

作者： mahmud Nahid-Al 西南科技大学

学位级别：硕士

太赫兹回旋加速器是一种自由电子激射器。它可以通过激发在强磁场中移动的电子的回旋共振来产生高频电磁波。它可以产生毫米波长的高功率。回旋加速器已应用于许多工业和高科技应用,包括在核聚变研究实验中加热等离子体,制造业作为处理... 详细信息

太赫兹回旋加速器是一种自由电子激射器。它可以通过激发在强磁场中移动的电子的回旋共振来产生高频电磁波。它可以产生毫米波长的高功率。回旋加速器已应用于许多工业和高科技应用,包括在核聚变研究实验中加热等离子体,制造业作为处理玻璃,复合材料和陶瓷以及退火（太阳能和半导体）的加速加热设备。开孔是回旋管的关键部件之一,对回旋管的开孔分析具有重要意义。由于回旋管开腔圆波导的Q因子的重要性以及表面粗糙度对圆波导的影响,研究圆柱波导TE48模式非常必要。本文对欧姆Q因子,衍射Q因子以及表面粗糙度（有效电导率）对回旋加速器开腔的影响进行了深入的理论分析。首先,我们讨论了回旋管开腔的Q因子和圆柱波导的基本理论。根据电磁场和波理论,提出了微波在圆柱波导腔中的传播和分析。为了分析受各种参数影响的表面粗糙度,我们还介绍了使用TE48模式的Q型开放式共振腔的具体分析。其次,设计了用于分析TE48模式圆柱圆形波导的TE11模式扇形波导。回旋管腔是一种圆柱形波导。可以发现,在扇形波导的径向表面上,TE11的分布电磁场与圆形波导的四分之一表面上的TE48模的分布电磁场相似。在半径为1.375mm的圆柱波导TE48的基础上,它的截止频率接近1THz。本文还给出了回旋腔TE48模式的初步设计思想。最后,通过商业软件CST对扇形波导TE11的几个数值结果进行了仿真,这表明TE48模式是圆柱波导内部电场的基础。基本上,还采用Matlab来分析圆柱波导TE48模式和圆扇形波导TE11模式下的E轮廓线。通过研究扇形波导径向表面上的TE11模场的能量损耗,可以获得圆形波导表面上TE48模场的能量损耗。此外,还分析了圆柱波导TE48模式的能量损耗特性。有效电导率是波导的表面粗糙度效应的参数之一。表面粗糙度对电导率有重要影响。此外,我们还讨论了在光滑表面和粗糙表面情况下有效电导率的特性。通过模拟TE11模式的幅度（abs）和相位（度）,可以进一步分析优化电导率的方法。对于圆柱波导TE48模式和扇形波导TE11模式,通过Matlab分析和CST软件仿真讨论了表面粗糙度的相关影响。获得了良好的工程仿真结果。本文的研究有助于我们了解圆柱圆形波导的Q因子的改善和粗糙表面的影响,并为陀螺仪的设计提供指导。

关键词：回旋管开放腔圆波导TE48模波导粗糙面损耗圆扇形波导TE11模

微生物厌氧耦合不同电子受体降解甲氧苄啶研究

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微生物厌氧耦合不同电子受体降解甲氧苄啶研究

作者： HASAN MD mahmud 哈尔滨工业大学

学位级别：硕士

污水处理厂是抗生素抗性基因(ARG)和抗生素抗性细菌(ARB)传播的重要源。如何提升抗生素脱毒/降解效率、有效阻断ARG的传播是环境领域的重大科学与技术问题。基于水体环境中频繁检出的磺胺类抗生素(Sulfonamides,SAs)去除的紧迫性以及控... 详细信息

污水处理厂是抗生素抗性基因(ARG)和抗生素抗性细菌(ARB)传播的重要源。如何提升抗生素脱毒/降解效率、有效阻断ARG的传播是环境领域的重大科学与技术问题。基于水体环境中频繁检出的磺胺类抗生素(Sulfonamides,SAs)去除的紧迫性以及控制抗生素抗性基因(ARGs)蔓延的必要性,本研究创新性地将磺胺类抗生素的生物降解过程与不同电子受体的厌氧呼吸过程耦合起来,研究不同分散式电子受体(硫酸盐、硝酸盐、三价铁)和可持续的固定式电子受体(生物电化学系统的阳极)条件下磺胺类抗生素的厌氧生物降解特征与降解途径和作用机制异同点。甲氧苄啶(trimethoprim,TMP)是一种在各种环境中频繁被检测到的磺胺类抗生素,对环境生态系统具有潜在危害。微生物是环境中抗生素类新兴有机污染物降解与转化的主要驱动因素。然而,甲氧苄啶与不同电子受体结合的厌氧生物降解的可行性和稳定性仍然知之甚少,功能微生物群落结构与组成鲜有报道。本研究的主要内容包括研究分散式电子受体(硫酸盐,硝酸盐和三价铁)和固定式电子受体(生物电化学系统中的阳极)引入时甲氧苄啶的生物降解特性、转化途径和核心微生物组特征。以市政活性污泥/河流沉积物为初始接种物,成功富集了几种TMP降解微生物菌群。驯化的菌群能够通过去甲基化途径转化TMP,以硫酸盐作为电子受体进一步降解羟基取代的去甲基化产物(4-去甲基-TMP)。TMP的生物降解遵循3参数S形动力学模型。潜在的降解菌(Acetobacterium,Desulfovibrio,Desulfobulbus和未鉴定的Peptococcaceae)和发酵罐(Lentimicrobium和Petrimonas)在驯化的菌群中显着富集。活化污泥和河流沉积物驯化获得TMP降解菌群共享相似的核心微生物组。在共基质乙酸钠存在或不存在下,通过富集的生物阳极群落(以电极作为电子受体)同时去除TMP并产生电流。共基质乙酸钠的存在与TMP的强化生物降解和提高的电流密切相关。当TMP用作唯一的电子供体时,与共代谢模式相比,TMP的降解速率和效率(192h,57%vs 24 h,99%)与产生电流(0.075mA vs 0.35 mA)均明显降低。更重要的是,TMP的厌氧生物降解还可以与其他电子受体如硝酸盐和三价铁的还原过程耦合。电子受体的供应可以明显提高不同初始接种物富集的功能微生物菌群的TMP降解效率。本研究结果为水体环境中抗生素如甲氧苄啶的强化降解去除和评估环境微生物介导的归趋与转化提供充分的理论基础和技术支撑。

关键词：甲氧苄啶厌氧生物降解不同电子受体微生物电化学核心微生物组

Security in Multicast Over α-μ Fading Channels with Orthogonal Frequency Division Multiplexing

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Journal of Computer and Communications 2022年第11期10卷 72-90页

作者： Mohammad mahmud Hasan Md. Zahurul Islam Sarkar Department of Electrical and Electronic Engineering Rajshahi University of Engineering and Technology Rajshahi Bangladesh

The orthogonal space-frequency block coding (OSFBC) with orthogonal frequency division multiplexing (OFDM) system reduces complexity in the receiver which improves the system performance significantly. Motivated by these advantages of OSFBC-OFDM system, this paper considers a secure wireless multicasting scenario through multiple-input multiple-output (MIMO) OFDM system employing OSFBC over frequency selective α-μ fading channels. The authors are interested to protect the desired signals from eavesdropping considering the impact of the number of multicast users and eavesdroppers, and the fading parameters α and μ. A mathematical model has been developed based on the closed-form analytical expressions of the probability of non-zero secrecy multicast capacity (PNSMC) and the secure outage probability for multi-casting (SOPM) to ensure the security in the presence of multiple eaves-droppers. The results show that the security in MIMO OSFBC OFDM system over α-μ fading is more sensitive to the magnitude of α and μ and this effect increases in the high signal-to-noise ratio (SNR) region of the main channel.

关键词： Orthogonal Space-Frequency Block Coding Orthogonal Frequency Division Multiplexing Probability of Non-Zero Secrecy Multicast Capacity Secure Outage Probability for Multicasting

An Optical Based Biosensor for the Determination of Ammonium in Aqueous Environment

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American Journal of Analytical Chemistry 2012年第5期3卷 364-370页

作者： Nur Ellina Azmi Jaafar Abdullah Musa Ahmad hamidah Sidek Lee Yook Heng Samsulida Abd Rahman Industrial Biotechnology Research Centre SIRIM Berhad Shah Alam Malaysia Industrial Biotechnology Research Centre SIRIM Berhad Shah Alam Malaysia. School of Chemical Sciences and Food Technology Faculty of Sciences and Technology Universiti Kebangsaan Malaysia Bangi Malaysia. School of Chemical Sciences and Food Technology Faculty of Sciences and Technology Universiti Kebangsaan Malaysia Bangi Malaysia.

A simple and rapid optical biosensor for the determination of ammonium was developed by immobilization of gluta-mate dehydrogenase (GLDH) and diaphorase (Dph) in chitosan film coated on a glass slide employing thiazolyl blue tetrazolium bromide (MTT) as a color indicator. The developed biosensor displays a purple color formation of formazan attributed to the unreacted NADH in the reaction system in the presence of ammonium. The color intensity was found to decrease proportionally with the increase of ammonium concentrations after 10 min exposure. The linearity of the biosensor towards ammonium was in the range of 16.8 – 70 μM (R2 = 0.9955) with detection limit of 11 μM. A good agreement (R2 = 0.9984) with indothymol method was obtained in the measurement of fish pond water samples. The effect of potential interferences such as metals ion has also been evaluated.

关键词： Optical Biosensor Glutamate Dehydrogenase Diaphorase Ammonium