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Sedimentary and geochemical evidence of Eocene climate change in the Xining Basin, northeastern Tibetan Plateau

Science China Earth Sciences 2018年第9期61卷 1292-1305页

作者： abu Sadat md SAYEM Zhengtang GUO Haibin WU Chunxia ZHANG Fan YANG Guoqiao XIAO Zhilin HE Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Department of Geological Sciences Jahangirnagar University Dhaka 1342 Bangladesh CAS Center for Excellence in Life and Paleoenvironment Bering 100044 China State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences China University of Geosciences Wuhan 430074 China

The northeastern Tibetan Plateau began to grow during the Eocene and it is important to understand the climatic history of Asia during this period of so-called ‘doubthouse' conditions. However, despite major advances in the last few decades,the evolutionary history and possible mechanisms of Eocene climate change in the northeastern Tibetan Plateau remain *** Xining Basin in the northeastern Tibetan Plateau contains a continuous sequence of Early to Late Eocene non-marine sediments which provides the opportunity to resolve long-term climate changes during this period. In this study, we report the results of analyses of lithofacies, sediment color and geochemistry of bulk samples collected from the Xijigou section of the Xining Basin. An abrupt lithofacies change between the Early(~52–40 Ma) and Late Eocene(~40–34 Ma) indicates a change in the depositional environment from a shallow lake to a playa lake in response to a significant climatic shift. During ~52–40 Ma,higher values of sediment redness(a*), redness/lightness(a*/L*) and higher modified Chemical Index of Weathering(CIW′)indicate a relatively warm and humid climate, while from ~40–34 Ma the lower values of a*, a*/L*and lower CIW′ imply subhumid to semi-arid climatic conditions. The paleoclimatic records indicate a long-term(~52–34 Ma) trend of decreasing chemical weathering, consistent with global climate change. An abrupt sharp excursion of the proxy records during ~42–40 Ma suggests a relatively brief warm interval, corresponding to the Middle Eocene Climatic Optimum(MECO). We suggest that global cooling substantially reduced humidity in inner Asia, resulting in sub-humid to semi-arid climatic conditions after 40 Ma in the Xining Basin, which may have been responsible for the long-term trend of decreasing chemical weathering during the Eocene.

关键词： Eocene Climate change Sediment color Chemical index of weathering Xining Basin Tibetan Plateau

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Whole Leea macrophylla ethanolic extract normalizes kidney deposits and recovers renal impairments in an ethylene glycol-induced urolithiasis model of rats

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Asian Pacific Journal of Tropical Medicine 2012年第7期5卷 533-538页

作者： abu Nasim Nizami md Atiar rahman Nazim Uddin Ahmed md Shahidul islam Department of Biochemistry and Molecular Biology University of ChittagongChittagong-4331Bangladesh Department of Biochemistry School of BiochemistryGenetics and MicrobiologyUniversity of KwaZulu-NatalDurban 4000South Africa Bangladesh Council of Scientific and Industrial research(BCSIr) Chittagong-4220Bangladesh

Objective:To investigate the antilithiatic effect of the whole Leea macrophylla(L macrophylla) roxb(Leeaeeae) ethanol extract in ediylene glycol-induced urolithiasis model of ***: Forty two seven weeks old male wistar albino rats were randomly divided into two major groups namely:preventive(n=18) and therapeutic(n=24).Preventive group was further subdivided into 3 groups of 6 rats namely:preventive control(PC),preventive lithiatic control(PLC) and preventive lithiatic ***(PLLM).Similarly,therapeutic group was also subdivided into 4 groups of 6 rats namely:therapeutic control(TC),therapeutic lithiatic control(TLC).therapeutic lithitatic L macrophylla(TLLM) and therapeutic lithiatic cystone(TLCYS).The lithiasis was induced by 0.75%(v/v) ethylene glycol in the drinking water of all groups except the PC and TC *** urinary ionic parameters such as calcium,inorganic phosphate,oxalate,magnesium & creatinine and renal morphology were altered by ediylene glycol,which were partially recovered by 14 d preventive and almost fully recovered by 28 d therapeutic intervention trials with L macrophylla extract(500 mg/kg BW daily).results:Significant difference on recovery was observed between preventive and dierapeutic interventional ***-urolithiatic effect of cystone was significantly(Pr than extracts.L macrophylla extract was found nontoxic in the acute toxicity ***:The results of this study demonstrated very promising antiurolithiatic effect of *** extract with preventive and therapeutic treatments in this experimental condition.

关键词： Urolithiasis Ethylene glycol Leea macrophylla Urinary parameter rats

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Data Classification Using Combination of Five Machine Learning Techniques

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Journal of Computer and Communications 2021年第12期9卷 48-62页

作者： md. Habibur rahman Jesmin Akhter abu Sayed md. Mostafizur rahaman md. Imdadul islam Department of Computer Science and Engineering Jahangirnagar University Dhaka Bangladesh Institute of Information Technology Jahangirnagar University Dhaka Bangladesh

Data clustering plays a vital role in object identification. In real life we mainly use the concept in biometric identification and object detection. In this paper we use Fuzzy Weighted rules, Fuzzy Inference System (FIS), Fuzzy C-Mean clustering (FCM), Support Vector Machine (SVM) and Artificial Neural Network (ANN) to distinguish three types of Iris data called Iris-Setosa, Iris-Versicolor and Iris-Virginica. Each class in the data table is identified by four-dimensional vector, where vectors are used as the input variable called: Sepal Length (SL), Sepal Width (SW), Petal Length (PL) and Petal Width (PW). The combination of five machine learning methods provides above 98% accuracy of class identification.

关键词： Co-Variance of Fuzzy rule Objective Function Surface Plot Confusion Matrix Scatterplot and Accuracy of Detection

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Determination of Array Gain of Single Hop to Achieve the Performance of a 2-Hop Wireless Link

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Journal of Computer and Communications 2018年第7期6卷 84-98页

作者： abu Sayed md. Mostafizur rahaman Jesmin Akhter md. rafsan Jani md. Imdadul islam Department of Computer Science and Engineering Jahangirnagar University Savar Dhaka Bangladesh Institute of Information Technology Jahangirnagar University Savar Dhaka Bangladesh

In adaptive beamforming system adaptive algorithm of digital filter is applied to update the weighting vector of the antenna elements to get antenna gain along the desired direction and attenuation along the jammer. The objective of the paper is to evaluate the threshold gain of the adaptive beam former along the line of sight (LOS) between the transmitter and the receiver (including jammer suppression) to make the single hop link comparable with 2-hop link. The single hop and 2-hop communication systems are compared in context of symbol error rate (SEr) under fading condition theoretically and verified by simulation. Finally we evaluate the numerical value of threshold gain of adaptive beamformer of two antenna elements under rayleigh and Nakagami-m fading conditions.

关键词： Array Antenna System BEr Threshold Array Gain Side Lobe Canceller Path Loss

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A highly efficient method for enriching TALEN or CrISPr/Cas9-edited mutant cells

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Journal of Genetics and Genomics 2016年第12期43卷 705-708页

作者： Hideyo Yasuda Eunsu Kim abu Musa md Talimur r.za Jin-Hoi Kim Department of Stem Cell and regenerative Biology Konkuk University

In recent years,genome editing with site-specific nucleases,such as ZFN（zinc finger nuclease）,TALEN（transcription activatorlike effector nucleases）,and CrISPr/Cas9（the type II bacterial clustered,regularly interspaced,short palindromic repeats-associated protein 9）,has gained popularity for use in cell lines,animals,and plants（Urnov et al.,2010;Miller et al.,2011;Cong et al.

关键词： A highly efficient method for enriching TALEN or CrISPr/Cas9-edited mutant cells gene DNA rNA ZFN

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A Study on the radioactivity Level in raw Materials, Final Products and Wastes of the Phosphate Fertilizer Industries in Bangladesh

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Journal of Environmental Protection 2012年第10期3卷 1393-1402页

作者： md. Abdus Samad md. abu Haydar md. Idris Ali Debasish Paul md. Mahbubur r. Bhuiyan Sheikh Mohammad A. islam Department of Physics Comilla University Comilla Bangladesh Department of Physics Jahangirnagar University Savar Bangladesh Health Physics and radioactive Waste Management Unit Institute of Nuclear Science and Technology Atomic Energy Research Establishment Savar Bangladesh

A study on the detection of probable radionuclides and their activity concentrations in the raw material (phosphate rock), final product (fertilizer) and waste samples collected from all the phosphate fertilizer factories (total two factories—A Diammonium Phosphate, DAP and a Triple Super Phosphate, TSP factory) in Bangladesh were carried out. A total of seven types of samples (grossly divided into solid and liquid types);liquid waste, waste-mixed river water, normal river water, phosphate rock, phosphate fertilizer, solid waste and normal soil;were analyzed under this study. raw material samples were collected only from the TSP fertilizer factory. Fertilizer, solid and liquid waste samples were collected from both the factories under study. Moreover, normal soil and natural surface water samples from the suitable areas adjacent to the factories were also collected for the comparison purpose. The samples were analyzed by gamma ray spectrometry technique using a Hyper-Pure Germanium (HPGe) detector of 40% relative efficiency. The analysis of the samples showed that only natural radionuclides such as 226ra, 232Th and 40K were present in the samples and no traces of artificial radioactivity were found in any of the samples. 40K was found below the detection limit in some samples. The analysis of the samples in the case of TSP fertilizer factory showed that the average activity concentrations of 226ra and 232Th and 40K in raw materials were 851.27 ± 7.10, 19.63 ± 6.57 and 54.06 ± 5.93 Bq/kg, respectively, in final product 211.90 ± 4.74, 42.48 ± 10.56 Bq/kg and ND (Not Detected), respectively, in solid waste 187.49 ± 4.88, 70.06 ± 11.76 and 289.27 ± 40.24 Bq/kg, respectively and in liquid waste 6.26 ± 0.63, 10.01 ± 1.39 Bq/L and ND, respectively. The measured results in the case of samples collected from DAP fertilizer factory showed that the average activity concentrations of 226ra and 232Th and 40K in the final product were 17.31 ± 3.92, 69.74 ± 9.88 and 48.46 ± 17.22

关键词： raw Materials radioactivity Phosphate Fertilizers and HPGe Detector

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Assessment of natural regeneration status and diversity of tree species in the biodiversity conservation areas of Northeastern Bangladesh

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Journal of Forestry research 2011年第4期22卷 551-559页

作者： md. Habibur rahman md. abu Sayed Arfin Khan Bishwajit roy Most. Jannatul Fardusi Department of Forestry and Environmental Science School of Agricul- ture and Mineral Sciences Shahjalal University of Science and Tech- nology Sylhet-3114 Bangladesh Department of Disturbance Ecology University of Bayreuth Bayreuth Germany

A study was conducted at two-biodivcrsity conservation areas of Northeastern Bangladesh （a part of Sylhet Forest Division） to assess the species composition, diversity and density of natural regeneration of tree species both indigenous and exotic species. Data were collected by stratified random quadrate method during January 2010 to July 2010. Totally 200 circular plots of 2 m〉〈2 m in size had 5 different habitat types of plants namely; forest, roadside, homestead （surrounding forest dwellers house）, fallow land and others （canals, streams and tea gardens side）, which included a total of 55 regenerating species belonging to 28 families. Meliaceae is the dominant family and shows the highest family importance value （26.3）, having six species, followed by Moraeeae （24.24）. Among the five habitat types, forest （43 species） possess the highes number of species, followed by roadside （23 species）. Total 15 exotic species among 9 families and 40 indigenous species with 24 families were recorded. For exotic species, Tectona grandis possess the highest relative density （11.7%） and relative frequency （10.5%）; Senna siamea had highest relative abundance （7.83%）. In case of indigenous species, Chickrassia tabularis possess the highest relative density （4.23%） and relative frequency （4%）; Dipterocarpus turbinatus bad the highest relative abundance （3.92%）. Tectona grandis （29.66） and Chickrassia tabularis （10.8） had the highest IVI for exotic and indigenous species respectively. Different diversity indic＇es such as Shanon-Winner diversity index,＇ species diversity index, species richness index, species evenness index, Simpson index and species dominance index, etc. were applied to quantify definite diversity. The regeneration of species associated with low levelsof disturbance was in the exotic Species. Study suggests that proper protection from human disturbances and scientific management of natural regeneration of two-study forests may lead a rich biodiversity site in the cou

关键词： biodiversity exotic species family importance value indigenous species quantitative characters

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Decay of rhizophora apiculata(Blume)and Xylocarpus granatum(Koenig)detrital sources in the Sarawak Mangrove,Malaysia

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Journal of Forestry research 2020年第2期31卷 613-623页

作者： abu Hena Mustafa Kamal Mohammed Muzammel Hoque Mohd Hanafi Idris Osumanu Haruna Ahmed md.Khurshid Alam Bhuiyan md.Masum Billah md.Nesarul Hoque zamri rosli Department of Animal Science and Fishery Faculty of Agriculture and Food SciencesUniversiti Putra Malaysia Campus Bintulu97008 BintuluSarawakMalaysia School of Fisheries and Aquaculture Sciences Universiti Malaysia Terengganu21030 Kuala TerengganuTerengganu Darul ImanMalaysia Department of Crop Science Faculty of Agriculture and Food SciencesUniversity Putra Malaysia Bintulu Sarawak Campus97008 BintuluSarawakMalaysia Department of Physical Chemistry Faculty of Marine and Environmental SciencesUniversity of CadizPuerto Real CampusPoligono San Pedro s/n Puerto Real11519 CadizSpain The United Graduate School of Agriculture Sciences Kagoshima University1-21-24 KorimotoKagoshima 890-0056Japan Department of Forestry Faculty of Agriculture and Food SciencesUniversiti Putra Malaysia Bintulu Sarawak Campus97008 BintuluSarawakMalaysia

Decaying mangrove detritus plays a significant role in nutrient cycling and fueling in both the forests and aquatic habitats where the detritus stems from estuarine and coastal food *** decay rates partly depend on the type of detritus,but most studies have thus far focused on leaf litter decay and decomposition,whereas other detrital sources(except for roots)have largely been *** compare the decay rates of rhizophora apiculata and Xylocarpus granatum non-leafy detritus(flowers,propagules,stipules,and twigs)with mangrove leaf litter in field studies,using litter bags during the dry and the wet seasons in the tropical mangrove forest of Sibuti,Sarawak,*** observed higher microbial decay rates of stipules,flowers,propagules,and twigs for both the *** and *** the wet *** contrast,leaf decay rates were higher during the dry *** rates depended on the lignin content of the detrital sources of both species,both during dry and wet ***,the half-life(T0.5)and 95%lifespan(T0.95)of non-leaf materials(flowers,propagules,stipules and twigs)for both species were remarkably longer than those of leaf *** decaying non-leafy detritus may play a significant role in nutrient and carbon cycling over longer time,when leaf litter is either being decomposing rapidly and/or being washed away by tidal flush and river ***,non-leafy(flowers,propagules,stipules and twigs)detritus should be taken into account when budgeting organic matter turnover in mangroves.

关键词： Microbial decay Decay constants Non-leafy detritus Sibuti mangrove Malaysia

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Investigation on Lanthanum Fluoride as a Novel Cathode Buffer Material Layer for the Enhancement of Stability and Performance of Organic Solar Cell

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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

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Potential bioactive phytochemicals, antioxidant properties and anticancer pathways of Nymphaea nouchali

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Asian Pacific Journal of Tropical Biomedicine 2020年第12期10卷 555-562页

作者： md.Nazim Uddin md.Abdus Samad md.abu Zubair md.zahurul Haque Kanika Mitra Tanzir Ahmed Khan md.Amir Hossain Ashikujaman Syed Aklima Afroze Institute of Food Science and Technology Bangladesh Council of Scientific and Industrial ResearchDhaka 1205Bangladesh School of Basic Medicine and Clinical Pharmacy China Pharmaceutical UniversityNanjingJiangsu 211198China Department of Food Technology and Nutritional Science Mawlana Bhashani Science and Technology UniversitySantoshTangail 1902Bangladesh Center for New Drug Safety Evaluation and research China Pharmaceutical UniversityJiangsuNanjing 211198China School of Pharmacy Lanzhou UniversityLanzhou 730000China School of Pharmacy China Pharmaceutical UniversityNanjingJiangsu 211198China

Objective:To investigate bioactive phytochemicals and antioxidant activities of Nymphaea nouchali and to explore its anticancer pathways by a network pharmacology ***:Using a spectrophotometer and high-performance liquid chromatography-diode array detector(HPLC-DAD),we quantified bioactive phytochemicals in methanolic extract of Nymphaea nouchali *** extracts were investigated for in vitro antioxidant *** of these bioactive phytochemicals were predicted and anticancer-associated pathways were analyzed by a network pharmacology ***,we identified the predicted genes associated with cancer pathways and the hub genes in the protein-protein interaction network of predicted ***:Quantitative results indicated the total phenolics,total flavonoids,and total proanthocyanidins in the methanolic extract of Nymphaea nouchali ***-DAD analysis showed rutin(39.44 mg),catechin(39.20 mg),myricetin(30.77 mg),ellagic acid(11.05 mg),gallic acid(3.67 mg),vanillic acid(0.75 mg),rosmarinic acid(4.81 mg),p-coumaric acid(3.35 mg),and quercetin(0.90 mg)in 1 g of dry *** extract showed the radical scavenging activities of 2,2-diphenyl-1-picrylhydrazyl,2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)and N,*** using network pharmacology,we predicted 130 target genes associated with cancer *** top hub genes(IL6,AKT1,EGFr,JUN,PTGS2,MAPK3,CASP3,and CXCL8)were also identified,which were associated with cancer pathways and interacted with bioactive phytochemicals of the methanolic extract of Nymphaea nouchali ***:Our study provides insights into the mechanism of anticancer activities of the methanolic extract of Nymphaea nouchali tuber.

关键词： Bioactive phytochemicals Anticancer pathways Malignancy Network pharmacology Nymphaea nouchali

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