检索结果-南通市图书馆

Genomic organization and evolution of ruminant lysozyme c genes

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2015年第1期36卷 1-17页

作者： David m.IRWIN Department of Laboratory medicine and Pathobiology University of Toronto Banting and Best Diabetes Centre University of Toronto

Ruminant stomach lysozyme is a long established model of adaptive gene evolution. Evolution of stomach lysozyme function required changes in the site of expression of the lysozyme c gene and changes in the enzymatic properties of the enzyme. In ruminant mammals, these changes were associated with a change in the size of the lysozyme c gene family. The recent release of near complete genome sequences from several ruminant species allows a more complete examination of the evolution and diversification of the lysozyme c gene family. Here we characterize the size of the lysozyme c gene family in extant ruminants and demonstrate that their pecoran ruminant ancestor had a family of at least 10 lysozyme c genes, which included at least two pseudogenes. Evolutionary analysis of the ruminant lysozyme c gene sequences demonstrate that each of the four exons of the lysozyme c gene has a unique evolutionary history, indicating that they participated independently in concerted evolution. These analyses also show that episodic changes in the evolutionary constraints on the protein sequences occurred, with lysozyme c genes expressed in the abomasum of the stomach of extant ruminant species showing the greatest levels of selective constraints.

关键词： lysozyme ruminant evolutionary Genomic extant stomach genomic constraints Ailuropoda duplication

A REGULAR VALUE OF COmPACT DEFORmATION

在线全文

学校读者我要写书评

暂无评论

Applied mathematics and mechanics(English Edition) 2006年第9期27卷 1265-1274页

作者： J.m.Soriano Departamento de Análisis matemático Facultad de matemáticas Universidad de Sevilla Aptdo. 1160 Sevilla 41080 Spain

Sufficient conditions were given to assert that between any two Banach spaces over K, Fredholm mappings share at least one .value in a specific open ball. The proof of the result is constructive and based upon continu... 详细信息

关键词： regular value continuation methods continuous dependence theorem C^1- homotopy proper mapping compact mapping Fredholm mapping topological complement Sard-Smale theorem

The Effects of Organic Ligands on the Survival of Daphnia in Zn Solution

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 1991年第4期4卷 433-440页

作者： m.H.WONG Department of Biology Hong Kong Baptist College 224 Waterloo Road Kowloon Hong Kong

Bioassays involving zinc alone and in combinations with two organic ligands, namely histidine and EDTA were conducted on Daphnia longispina over a period of 96 h. The percentage of mortality was recorded and the median Lethal Concentration (LC50) at 96 h estmated. The 96 h LC50 of D. longispina in zinc solution was 91 μg/1 whereas no values of LC50 were revealed when D. longispina were exposed to histidine or EDTA alone although the organic ligands seemed to exert harmful effects (e.g. The mortality at 96 h was 18% at a concentration of 10×10^(-5) m histidine and 16% at a concentration of 6×10~6 m EDTA). However, addition of histidine and EDTA effectively reduced the toxicity of zinc to the test animals. The detoxification effect was the most obvious at the concentration of 100×g/1 Zn added with 5×10^(-5) m histidine and 3×10^(-6) m EDTA where 7-fold and 5-fold reduction in terms of mortality were noted.

关键词： Zn

Influence of alkaline treatment and fiber loading on the physical and mechanical properties of kenaf/polypropylene composites for variety of applications

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:materials International 2016年第6期26卷 657-664页

作者： majid Niaz Akhtar Abu Bakar Sulong m.K.Fadzly Radzi N.F.Ismail m.R.Raza Norhamidi muhamad muhammad Azhar Khan Department of Physics COMSATS Institute of Information Technology Department of mechanical and materials Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia Department of Basic Sciences and Humanities Muhammad Nawaz Sharief University of Engineering and Technology(MNSUET) Department of mechanical Engineering COMSATS Institute of Information Technology Department of Physics The Islamia University of Bahawalpur

Due to current trend and increasing interest towards natural based fiber products, Kenaf(Hibiscus cannabinus)fibers have been used for the developments of many products. Therefore, Kenaf fiber-reinforced composites have been widely used in engineering and industrial applications. The present work deals with the fabricating and characterization of untreated and treated kenaf/polypropylene(PP)-reinforced composites. Composites of PP reinforced with treated and untreated kenaf fibers were fabricated using the injection molding *** fiber loadings of 10, 20, 30, 40, 50 wt% treated and untreated kenaf composites were also prepared. Xray diffraction(XRD), scanning electron microscopy(SEm), Fourier transform infrared(FTIR) spectroscopy and thermo gravimetric analysis(TGA) were performed on the treated, untreated kenaf fibers and kenaf/PP composites. moreover, the alkaline-treated kenaf composites exhibit better physical, morphological, and mechanical properties because of the compatibility of kenaf with PP. However, variations in tensile and flexural properties depend on treatment and kenaf fiber contents. The percentage increase in the mechanical properties of the treated kenaf/PP composites relative to that of PP was also measured. In addition, 40 wt%kenaf fiber loading resulted in higher mechanical properties. By contrast, kenaf/PP composite with 50% fiber loading was not successfully prepared because of improper mixing and the burning of kenaf fibers in the PP matrix. To conclude, 40% kenaf/PP composites with superior physical and mechanical properties may be used in variety of applications such as automotive, sports, construction, animal bedding, and mass production industries.

关键词： Kenaf composites microstructures Physical properties mechanical Testing Injection-molding

Design of high-speed and low-power finite-word-length PID controllers

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Control Theory and Technology 2014年第1期12卷 68-83页

作者： A. K. OUDJIDA N. CHAILLET A. LIACHA m. L. BERRANDJIA m. HAmERLAIN Centre de Developpement des Technologies Avancees Algiers Algeria FEmTO-ST Institute Besancon France

ASIC or FPGA implementation of a finite word-length PID controller requires a double expertise： in control system and hardware design. In this paper, we only focus on the hardware side of the problem. We show how to design configurable fixed-point PIDs to satisfy applications requiring minimal power consumption, or high control-rate, or both together. As multiply operation is the engine of PID, we experienced three algorithms： Booth, modified Booth, and a new recursive multi-bit multiplication algorithm. This later enables the construction of finely grained PID structures with bit-level and unit-time precision. Such a feature permits to tailor the PID to the desired performance and power budget. All PIDs are implemented at register-transfer4evel （RTL） level as technology-independent reusable IP-cores. They are reconfigurable according to two compilemtime constants： set-point word-length and latency. To make PID design easily reproducible, all necessary implementation details are provided and discussed.

关键词： Design-reuse Embedded finite-word-length (FWL) controllers Intellectual property (IP) Linear time invariant (LTI) systems Low-power and speed optimization PID

mapping Supergene/Hypogene Alteration Signatures with Landsat ETm+ Data: Paishanlou Gold mine, Liaoning Province, China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of China University of Geosciences 2005年第1期16卷 38-44页

作者： malogo J m Kongola School of Resources and Civil Engineering Northeastern University Shenyang 110004 China

Noise removal routines (destriping) were performed on Landsat ETm+ data as adjustments for atmospheric and distortion factors, prior to further image enhancement and interpretation. The image enhancement techniques were contrast stretching, density slicing, spatial filtering, Fourier analysis, brightness inversion, band combinations, and band ratioing. It has been revealed that, owing to the presence of gossans at Paishanlou, the mixture of iron oxide and clay minerals affects the spectral reflectance in satellite data. The mineral and hydrothermal composite images with band ratios 5/7+5/4+3/1 RGB and 5/7+3/1+4/3 RGB, respectively, yielded the best results for their sensitivity to lithologic variables, and lack of statistical redundancy. Ratio 3/1 clearly highlighted ferric (Fe 3+ ) iron; 5/4 depicted ferrous (Fe 2+ ) iron, and 5/7 depicted clays, carbonates, and hydroxyl bearing minerals. Vegetation was also successfully discriminated by ratio 5/7. Finally, coupled with field surveys, petrographical and geochemical data, the observed anomalies led to the discovery of three new sites, which are gold mineralized. The prime objective of this study was to map supergene and/or hypogene signatures in the gold mineralized areas using Landsat ETm+ data at Paishanlou.

关键词： gold signatures hypogene/supergene alteration Landsat ETm+.

Parametric Study of Turbulent Flow in a Three-Dimensional Side-Dump Combustor

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 1993年第4期2卷 282-287页

作者： T.m.Liou Department of Power mechanical Engineering National Tsing Hua University

Turbulent flows in a three-dimensional side-dump combustor under various side-inlet angles and head heights are presented in terms of the axial mean velocity,swirl intensity,size of the head recirculation zone,and fraction of the inlet mass flow rate transported into the head *** turbulence model adopted is the algebraic Reynolds stress(k-ε-A)*** effect of the side-inlet angle and the head height on the characteristics of the confined impinging flows are documented and some improved explanations to the existence of the optimum inlet angle and head height are addressed in this study.

关键词： k-ε-A model side-dump combustor side-inlet angle head height

Statistical analysis and concentration of iron ore using Longi LGS 500 WHImS

在线全文

学校读者我要写书评

暂无评论

矿业科学技术学报：英文版 2016年第5期26卷 769-775页

作者： makhula m.J. Falcon R.m.S. Bergmann C.P. Bada S.O. Department of mineral Processing Division Mintek Johannesburg 2125 South Africa School of Chemical and metallurgical Engineering University of the Witwatersrand Johannesburg 2050 South Africa

A Longi LGS 500 wet high intensity magnetic separator(WHImS) was used to concentrate a fine, low grade South African hematite ore. The ore was prepared into different size fractions and was subjected to changes in pulp density, magnetic field intensity and pulsation frequency which followed a 33 full factorial matrix. The concentrate mass yield and Fe grade were selected as the dependent responses to the changes. The analysis of variance(ANOVA) shows that the variables investigated are significant to the material's response to magnetic separation. This significance was in the order of magnetic field intensity followed by pulsation frequency and then pulp density. It was also noted that a single stage magnetic separation has a potential to upgrade a feed( 75 lm and 40% Fe) to a 55% Fe grade, as the pulsation frequency increases. In addition, the model predictions and actual data were in good agreement, reporting regression coefficients within acceptable ranges.

关键词： magnetic separation Longi LGS 500 Hematite ANOVA

NDm-1 in the Indian environment:hitherto the problem is not disquieting

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical medicine 2012年第4期5卷 335-336页

作者： mohd Shahid Fatima Khan m Salman Shah Indu Shukla Fatima Shujatullah Haris m Khan Abida malik lqbal m Khan Section of Antimicrobial Agents & Drug Resistance Research and molecular Biology Department of Medical MicrobiologyJawaharlal Nehru Medical College & HospitalAligarh Muslim UniversityAligarh-202002Ultar PradeshIndia Department of Community medicine Jawaharlal Nehru Medical College & HospitalAligarh Muslim UniversityAligarh-202002Uttar PradeshIndia Section of Antimicrobial Agents & Drug Resistance Research and molecular Biology Department of Medical MicrobiologyJawaharlal Nehru Medical College & HospitalAligarh Muslim UniversityAligarh-202002Uttar PradeshIndia

blaNDm-1 is a recently described novel plasmid-mediated resis tance determinant that confes resistance to carbapenems. Bacteria harbouring NDm-1 have been reported from the clinical *** are also reported and warned as impending gut colonist,and recently described from the environment of the capital city of India,indicating the potential as a reservoir for future infections.

关键词： reservoir Indian Bacteria plasmid determinant latter isolates award preventive