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Invaders’ control on post-disturbance succession in coastal mangroves

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Journal of Plant Ecology 2012年第2期5卷 157-166页

作者： Shekhar R.Biswas Md.Saiful Islam Khan azim U.Mallik Department of Ecology and Evolutionary Biology University of Toronto3359 Mississauga RoadMississaugaOntario L5L1C6Canada United Nations Environment Programme-World Conservation Monitoring Centre(UNEP-WCMC) Cambridge CB30DLUK Forest and Landscape LIFECopenhagen University1958 Frederiksberg CDenmark Department of Biology Lakehead University955 Oliver RoadThunder BayOntario P7B 5E1Canada

Aims In recent years,coastal mangroves have been frequently affected by large disturbances(cyclones,hurricanes,flooding and tsunamis)and post-disturbance vegetation is often dominated by small stature mangrove,mangrove-associate and non-mangrove species potentially affecting ecosystem *** on the processes of mangrove vegetation development and recovery(succession)following normal and large disturbances will benefit practitioners in designing robust ecosystem management/restoration *** we propose a conceptual model of disturbance-mediated succession in *** Based on field observations and species’life history traits,we develop conceptual models of mangrove succession under normal disturbance regime and recently experienced increased frequency of large *** evaluate our conceptual models by conducting a scenario testing *** Findings We suggest two predominant processes affecting mangrove succession after disturbance:propagule limitation due to damage of seed producing mature trees and dispersal barrier resulting from biological invasion associated with large *** argue that large disturbances affect mature trees more than the small-stature non-tree(shrubs,herbs and climbers)species creating a larger propagule shortage for mangrove tree species than non-tree ***,large disturbances facilitate invasion of free-floating aquatics,which may interfere with the flow-facilitated propagule dispersal and seedling establishment of mangrove *** a scenario testing experiment,we have shown that similar levels of disturbance impact vegetation development and recovery differently depending on the presence or absence of invasive *** conclude that since biological invasion is one of the major drivers of post-disturbance mangrove succession,the dimension of biological invasion should be included in prediction,management and restoration of mangrove forests.

关键词： biological invasion cryptic ecological degradation dispersal barrier large disturbances mangrove restoration mangrove succession

Comparative assessment of total polyphenols, antioxidant and antimicrobial activity of different tea varieties of Bangladesh

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Asian Pacific Journal of Tropical Biomedicine 2017年第4期7卷 352-357页

作者： Yead Morshed Nibir Ahmed Faisal Sumit Anwarul azim Akhand Nazmul Ahsan Mohammad Shahnoor Hossain Department of Genetic Engineering and Biotechnology University of DhakaDhaka 1000Bangladesh

Objective: To determine the total polyphenol content, antioxidant activity and antibacterial properties of the extracts of different Bangladeshi tea varieties such as flowery broken orange pekoe, broken orange pekoe, red dust and green ***: Total phenolic and flavonoid contents were determined by Folin–Ciocalteu and aluminum chloride colorimetric assay, *** antioxidant capacity was determined by ferric ion reducing antioxidant power and phosphomolybdenum *** activity was evaluated by disc diffusion method in agar plate and subsequently, the minimum inhibitory concentration was determined by broth dilution ***: Total phenolic and flavonoid contents were significantly higher(P < 0.05) in green tea compared to other three black tea *** green tea also showed a higher free radical scavenging and antioxidant activities than all the other tea varieties tested(P < 0.05).In addition, the extracts of all four tea varieties showed inhibitory activity against several pathogenic bacteria and also the same trend of higher antimicrobial activity of green tea than other tea varieties was ***: Taken together, the results of this study demonstrated that Bangladeshi tea,especially the green tea, may act as a substitute for natural antioxidants and as a promising antibacterial agent for beneficial influence in human health.

关键词： Tea extracts Antioxidant activity Antibacterial activity Total phenolic content

Performance of the Aluminide Coating of SomeLow Alloy Steels

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Journal of Materials Science & Technology 1997年第6期13卷 462-466页

作者： H.M.Soliman and M.E.Abd E1-azim(Metallurgy Dept., Atomic Energy Authority, Cairo, Egypt ) Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Two low alloy steels 0.5Cr-0.5Mo-0.25V and H85 were pack-aluminized at 900°for 4 h by using Fe-Al powder mixture containing 48% Fe, 20.6% Al- 29.4% Al2O3 and 2% NH4Cl by weight. The microhardness and oxidation resistance at 900℃ of the aluminide coatings were studied. It was found that pack-aluminizing improves the microhardness of the 0.5Cro.5Mo-0.25V steel while it reduces the microhardness of the H85 steel. Pack aluminizing highly improves the oxidation resistance after 20h exposure at 900℃ in air for the investigated steels.

关键词： Cr Performance of the Aluminide Coating of SomeLow Alloy Steels

Computational Performances of OFDM Using Different FFT Algorithms

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International Journal of Communications, Network and System Sciences 2013年第7期6卷 346-350页

作者： Anwarul azim Department of Electrical and Electronic Engineering East West University Dhaka Bangladesh

In this paper, an intuitive comparison of the computational performance of orthogonal frequency division multiplexing (OFDM) system has been made in terms of complex calculations required using different Fourier transform techniques. The different transform techniques are introduced such as discrete Fourier transform (DFT) and various types of fast Fourier transform (FFT) as 2-radix FFT, 4-radix FFT etc. and the very recent very fast Fourier transform (VFFT). With intuitive mathematical analysis, it has been shown that with the reduced complexity that VFFT can offer, OFDM performance can be greatly improved in terms of calculations needed.

关键词： Orthogonal Frequency Division Multiplexing (OFDM) Discreate Fourier Transform (DFT) Fast Fourier Transform (FFT) Very Fast Fourier Transform (VFFT)

Identification of Textile Defects Based on GLCM and Neural Networks

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Journal of Computer and Communications 2015年第12期3卷 1-8页

作者： Gamil Abdel azim College of Computers & Informatics Canal University Ismailia Egypt

In modern textile industry, Tissue online Automatic Inspection (TAI) is becoming an attractive alternative to Human Vision Inspection (HVI). HVI needs a high level of attention nevertheless leading to low performance in terms of tissue inspection. Based on the co-occurrence matrix and its statistical features, as an approach for defects textile identification in the digital image, TAI can potentially provide an objective and reliable evaluation on the fabric production quality. The goal of most TAI systems is to detect the presence of faults in textiles and accurately locate the position of the defects. The motivation behind the fabric defects identification is to enable an on-line quality control of the weaving process. In this paper, we proposed a method based on texture analysis and neural networks to identify the textile defects. A feature extractor is designed based on Gray Level Co-occurrence Matrix (GLCM). A neural network is used as a classifier to identify the textile defects. The numerical simulation showed that the error recognition rates were 100% for the training and 100%, 91% for the best and worst testing respectively.

关键词： Image Processing Neural Network Gray-Level Co-Occurrence Matrices (GLCM)

Water deficit and cold stress on the evening primrose seed quality

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Journal of Agricultural Science and Technology 2009年第8期3卷 22-30页

作者： azim Ghasemnezhad Bernd Honermeier Department of Horticulture Gorgan University of Agricultural Sciences and Natural Resources Gorgan 49174 Iran Institute of Crop Science and Plant Breeding Justus Liebig University Giessen 31180 Germany

Evening primrose is a valuable oilseed crop with pharmaceutical and nutritional supplementation. Due to presence of valuable and rare gamma linolenic fatty acid, research on this plant has been started since 1970s by German and Britain scientists. Information about evening primrose cultivation is going to rise. Following to pervious studies the goal of this experiment was to clarify the effect of water and temperature stresses on seed yield and seed quality. Results showed that seed yield was significantly influenced by low temperature and water deficit. Plants grown under cold stress during rosette stage produced a lower seed yield than controls. The lowest seed yield was observed in the plants grown under permanent stress. Although the oil content of seeds was not influenced by low temperature stress, water stress strongly influenced the oil content and water stress stimulates oil accumulation. Like oil content, the GLA production seems to be increased under water stress conditions.

关键词： water stress low temperature stress eveningprimrose seed oil gamma linolenic acid

Impairment of extra-high frequency auditory thresholds in subjects with elevated levels of fasting blood glucose

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Journal of Otology 2018年第1期13卷 29-35页

作者： Anindya Das Ahmed Faisal Sumit Nazmul Ahsan Masashi Kato Nobutaka Ohgami Anwarul azim Akhand Department of Genetic Engineering and Biotechnology University of Dhaka Dhaka Bangladesh BRAC James P Grant School of Public Health BRAC University Dhaka Bangladesh Department of Occupational and Environmental Health Nagoya University Graduate School of Medicine Nagoya Japan

This study was performed to assess whether there is an association between elevated Fasting Blood Glucose(FBG) and hearing impairment in Bangladeshi population. A total of 142 subjects(72 with elevated FBG; 70 control) were included in the study. The mean auditory thresholds of the control subjects at 1,4,8 and 12 kHz frequencies were 6.35 ± 0.35,10.07 ± 0.91,27.57 ± 1.82, 51.28 ± 3.01 dB SPL(decibel sound pressure level), respectively and that of the subjects with elevated FBG were 8.33 ± 0.66,14.37 ± 1.14, 38.96 土 2.23, and 71.11 ± 2.96 ***. The auditory thresholds of the subjects with elevated FBG were significantly(p 10 years) showed significantly(p 40 years) and younger(<40 years) age groups compared to the respective controls. The binary logistic regression analysis showed a 5.79-fold increase in the odds of extra-high frequency hearing impairment in diabetic subjects after adjustment for age, gender and BMI. This study provides conclusive evidence that auditory threshold at an extra-high frequency could be a sensitive marker for hearing impairment in diabetic subjects.

关键词： Fasting blood glucose Hearing impairment Auditory thresholds Extra-high frequency

Effectiveness of revascularization of the ulcerated foot in diabetic patients with peripheral artery disease for one year follow-up

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Frontiers in Biology 2018年第6期13卷 458-463页

作者： Mohammad Momen Gharibvand Mina Mounesi Arman Shahriari Asghar Sharif Najafi azim Motamed far Atefeh Roumi Department of Radiology school ofmedicineAhvaz Jundishapur University of Medical SciencesAhvazIran Department of Internal Medicin School of MedicineAhvaz Jundishapur University of Medical SciencesRazi HospitalAhvazIran

Diabetes is an important risk factor for atherosclerosis. The diabetic foot is characterized by the presence of arteriopathy and neuropathy. When ischemia is diagnosed, restoration of pulsatile blood flow by revascularization may be considered for salvaging the limb. The treatment options are angioplasty with or without stenting and surgical bypass or hybrid procedures combining the two. To evaluate the outcomes of severe ischemic diabetic foot ulcers for which percutaneous transluminal angioplasty (PTA) was considered as the first-line vascular procedure. Factors associated with successful PTA were also evaluated. In 80 consecutive diabetic patients with foot ulcers and severe limb ischemia, PTAwas performed if feasible. All patients were followed until healing or for one year. Clinical and angiographic factors in fluencing outcomes after PTA were sought by univariate and multivariate analysis. PTAwas done in 73 of the 80 (91.2%) patients, and considered clinically succe ssful in 58(79.9%). Successful PTA was significantly higher in patients with Superficial femoral artery, posterior Tibialis and dorsalis pedis arteries involvement in the univariate analysis. Seven patients were expired during the study follow up due to MI, pulmonary thromboembolism and GI bleeding. PTA in diabetic patients with severe ischemic foot ulcers provided favorable. Some parameters could be used for predicting PTA successfulness.

关键词： percutaneous transluminal angioplasty revascularization diabetes

Porphyria cutanea tarda as a complication of therapy for chronic hepatitis C

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World Journal of Gastroenterology 2008年第38期14卷 5913-5915页

作者： James azim Heather McCurdy Richard H Moseley Division of Gastroenterology Department of Internal Medicine Department of Veterans Affairs Medical Center and University of Michigan School of Medicine Ann ArborMichigan United States

There is a strong association between porphyria cutanea tarda (PCT) and chronic viral hepatitis C. Therapy for chronic viral hepatitis C may improve PCT. However, there are only a few reports of the de novo development of PCT during therapy for chronic viral hepatitis C. We describe the development of PCT in a 56-year-old patient with chronic viral hepatitis C after 12 wk of peginterferon/ribavirin therapy. In addition, the patient was homozygous for the H63D hereditary hemochromatosis gene (HFE ) mutation. The association of PCT with chronic viral hepatitis C and the possible role of hepatic iron overload and ribavirin-induced hemolytic anemia in the development of PCT during therapy for chronic viral hepatitis C are discussed.

关键词： Porphyria Hepatitis C virus Ribavirin Pegylated interferon Hemochromatosis