检索结果-南通市图书馆

Dual DVCC Based Voltage-Mode Digitally Programmable Biquadratic Filter

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Circuits and Systems 2014年第1期5卷 1-6页

作者： ale.Imran Deepesh Arora Rishabh Kumar Department of Electronics Engineering Aligarh Muslim University Aligarh India

The recent advances in IC technology have led to the trend of designing hybrid systems to benefit both analog and the digital domain. Among analog circuits, multifunctional filter along with multiphase oscillator constitutes a building block of critical importance. In this paper, a digitally reconfigurable multi-input-multi-output voltage mode multifunctional biquadratic filter has been presented. The circuit comprises of two differential voltage current conveyors (DVCCs), two grounded capacitors and two floating resistors. The digital controllability is incorporated using a current-summing network (CSN). Tunability of quality factor is achieved by the use of a 3-bit digital control word while keeping the resonant frequency constant. PSPICE simulations using TSMC 0.25 μm CMOS technology have been performed to validate the theoretically predicted results.

关键词： Voltage-Mode Differential Voltage Current Conveyor (DVCC) Multifunctional Filter Digitally Controlled Circuits Current Summing Network

应用富血小板血浆治疗缺血性股骨头坏死的系统评价

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

应用富血小板血浆治疗缺血性股骨头坏死的系统评价

作者： Bikash ale 吉林大学

学位级别：硕士

背景:近年来,整形外科领域“再生医学”技术的应用提供了解决多种难治性、慢性和功能障碍性疾病的方案和希望。再生医学中主要生物制剂之一富血小板血浆(platelet rich plasma,PRP)正在成为整形外科相关创伤和疾病治疗的里程碑,例如缺... 详细信息

背景:近年来,整形外科领域“再生医学”技术的应用提供了解决多种难治性、慢性和功能障碍性疾病的方案和希望。再生医学中主要生物制剂之一富血小板血浆(platelet rich plasma,PRP)正在成为整形外科相关创伤和疾病治疗的里程碑,例如缺血性股骨头坏死(avascular necrosis of the femoral head).富血小板血浆是种具有比全血更高血小板浓度的血液浓集物,当被激活时会释放大量的具有生物活性的自体同源性生长因子(growth factors,GFs)和生物活性蛋白,而这些生长因子和活性蛋白已被发现可能具有促进组织愈合和骨再生的功效。尽管有许多传统手术治疗(例如外科髓芯减压术和全髋关节置换术),但应探求非手术疗法以改善病况,仍具有重要临床意义,保护髋关节。因此,本文试图介绍一种正在兴起的新型无创PRP疗法的疗效。这种疗法可通过简单的注入式过程,治疗一种常见的却病理进程严重的、可致残的疾病--AVNFH。股骨头缺血性坏死(又称股骨头坏死)的股骨头(AVNFH)是一个渐进的致残疾病,股骨头内的小梁骨和骨髓细胞死于血液供应的中断。血管的损失意味着这些骨骼的血液供应中断,通过非常有限的空间和有限制的侧支循环,最终导致骨细胞死亡,导致骨质破坏、关节面塌陷。AVNFH通常影响30-50岁,处于生命活跃阶段的相对年轻的和中年人,主要发生在男性。尽管世界范围内的疾病患病率是未知的,但在美国每年有10,000至20,000个新病例被单独确诊。虽然缺乏足够的研究,但有一些研究表明,亚洲国家疾病的流行也在急剧增加。在香港和中国,估计成人AVNFH的病例很高。每年有75,000-150,000例新病例出现在中国。在赵先生最近的研究中估计在15岁以上的中国普通人群中股骨头非创伤性无血管性坏死病例约为812万例。尽管有许多理论被假定,AVNFH背后的确切病理生理学仍不清楚。然而,最终的共同途径是破坏股骨头的血管供应。基本上,三大类动脉向股骨头供血;股骨头后部上部营养动脉组由内侧股动脉回旋动脉的深部分支,后下营养动脉也由内侧股动脉回旋动脉和下臀动脉的梨状分支引起。一旦对股骨头的血管供应受到损害,就会发生细胞死亡。这导致小骨间隙中的骨基质和坏死骨髓中的空隙。虽然修复过程由修复组织开始,但是它不能恢复其前病状态的股骨头稳定性。此外,还指出了AVNFH的病理生理机制,直接细胞毒性的改变和间叶间质细胞分化受损。由于该疾病是隐匿的,并且可以保持无症状或微小或非特异性症状,直到进展到晚期阶段,诊断AVNFH是不可避免的依靠成像发现的读数。AVNFH成像的特征是重要的,因为疾病的准确分期对于适当地治疗每个患者至关重要。在疾病早期需要高分辨率,三维成像(如磁共振成像(MRI)或计算机断层扫描(CT);而即使是平片也可以区分晚期的病变。然而,随着疾病缓慢发展为慢性发作,阴部腹股沟疼痛(单侧或双侧)的广泛症状,臀部,膝盖或大腿前外侧的疼痛可能存在有限的运动范围,特别是髋外展和内旋。症状通常随负重增加而缓解。AVNFH的处置以关注关节保护的目的考虑主要有两种方式。这些包括:非手术和手术方法。多种因素可能影响这些方法的选择,如病人的年龄,病变的大小和位置,疾病的病因和病情等。非手术治疗主要适用于具有小病变的AVNFH的早期阶段或在外科手术禁忌的患者中。治疗目的是减轻患侧髋关节的负重,包括通过使用拐杖或助行器、限制活动、固定和牵引以及物理治疗,如电磁刺激、体外冲击波治疗和高压氧。然而,这些措施在晚期阶段没有任何作用,或在预防疾病进展方面作用有限。类似地,降脂药物、抗凝剂、血管舒张剂和二膦酸盐也可以使用,中药在疾病早期中似乎也是有效的。大多数研究得出结论,与手术方法相比,非手术方法在减轻疼痛和保持活动性方面没有太大的效果。通常,常规手术方法在股骨头的前塌陷或塌陷前阶段之间变化。股骨头头部手术如核心减压、非血管化骨移植、截骨术、血管化骨移植,通常用于症状性前崩溃病变或小型后崩溃病变的保留性手术,而全髋关节置换术(THR)是到现在为止对于晚期疾病唯一确定的传统外科治疗方式。富含血小板血浆是通过新鲜全血离心获得的,血小板浓度高于基线水平的自体血血浆的过程。注射治疗的过程中重新引入这些自体浓缩血小板到受伤区域称为PRP治疗。血液中血小板计数正常范围为150000/μL-350000/μL。多项研究表明,血小板浓度增长四倍基线以上(100万血小板/UL),其临床效率可以达到预期。大体上,富血小板血浆含有3-5倍生长因子。科学结论指出,血小板包含各种生长因子、生物活性蛋白、凝血因子、粘附分子、细胞因子、整合素和趋化因子,其基本上是负责止血、抗炎、组织再生和愈合过程中最强大的功能性质,甚至改善骨形成。由于PRP通过离心过程获得,其中含有高度浓缩的血小板和大量血小板相

关键词：富血小板血浆(PRP) 缺血性股骨坏死生长因子再生医学脂肪干细胞

Efficient metallization of magnetite concentrate by reduction with agave bagasse as a source of reducing agents

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 603-611页

作者： Diana Cholico-González NoemíOrtiz Lara Mario Alberto Sánchez Miranda Ricardo Morale. Estrella Ramiro Escudero García Carlos ale.n Patiño CONACYT-Metallurgy and Materials Research Institute Michoacana University of San Nicolás de HidalgoMorelia CP 58030Mexico Metallurgy and Materials Research Institute Michoacana University of San Nicolás de HidalgoMorelia CP 58030Mexico

The reduction behavior and metallization degree of magnetite concentrate with agave bagasse were investigated in an inert *** effects of temperature,biomass content,and residence time on reduction experiments and metallization degree were investigated by X-ray diffraction and scanning electron *** with other types of biomass,agave bagasse had lower contents of nitrogen,sulfur,and ash.X-ray diffraction analysis showed that the metallization degree improved with increasing temperature and biomass *** metallization was achieved at 1100℃ for 30 min with 65:35 and 50:50 ratios of the magnetite concentrate to the agave *** results demonstrate that agave bagasse promotes the efficient metallization of magnetite concentrate without the external addition of a reducing ***,this biomass is a technical suitable alternative to replace fossil fuels in steelmaking.

关键词： magnetite concentrate agave bagasse biomass reduction metallization degree

Power efficient scheme for self localization in wireless sensor networks

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

通讯和计算机（中英文版） 2009年第10期6卷 37-43,53页

作者： Allon Rai Sangita ale.Syed S. Rizvi Aasia Riasat Computer Science and Engineering Department University of Bridgeport Bridgeport 06604 USA Computer Science Department Institute of Business Management Karachi 78100 Pakistan

With the tremendous applications of the wireless sensor network, self-localization has become one of the challenging subject matter that has gained attention of many researchers in the field of wireless sensor network. Localization is the process of assigning or computing the location of the sensor nodes in a sensor network. As the sensor nodes are deployed randomly, we do not have any knowledge about their location in advance. As a result, this becomes very important that they localize themselves as manual deployment of sensor node is not feasible. Also, in WSN the main problem is the power as the sensor nodes have very limited power source. This paper provides a novel solution for localizing the sensor nodes using controlled power of the beacon nodes such that we will have longer life of the beacon nodes which plays a vital role in the process of localization as it is the only special nodes that has the information about its location when they are deployed such that the remaining ordinary nodes can localize themselves in accordance with these beacon node. We develop a novel model that first finds the distance of the sensor nodes then it finds the location of the unknown sensor nodes in power efficient manner. Our simulation results show the effectiveness of the proposed methodology in terms of controlled and reduced power.

关键词：无线传感器网络网络定位传感器节点节点位置省电本地化仿真结果控制权

MeteoRead: Client Software for Inserting Observed Atmospheric Data into MySQL<sub>TM</sub>Database and Downloading them into Different File Format

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 Software Engineering and Applications 2021年第10期14卷 563-574页

作者： Beáta Szabó-Takács Tamás Takács ale. Roček Department of Atmospheric Matter Fluxes and Long-Range Transport Global Change Research Institute Brno Czech Republic Faculty of Engineering and Information Technology University of Pécs Pécs Hungary Institute of Computer Science Masaryk University Brno Czech Republic

The investigation of the tendency of climate change and its effects on ecology, economy and sociology is essential for long term policy making. The long-term measurement of the physical and chemical properties of the atmosphere with state-of-the-arts instruments provides high-quality data for these studies. The evaluated data are stored in really special file structures and formats that cannot be inserted in one common database. Moreover, the observed data usually available in ASCII format and the users sometimes need to convert them in other format. The file conversion is usually time consuming procedure and can contribute to the uncertainties. MeteoRead is a client database software that imports the observed atmospheric data e.g. wind direction, wind speed, aerosol particle concentration etc. and makes them available in different file formats, which are most commonly used in climate research. This JavaTM based program applies the Structured Query Language (SQL) functions such as table creation on a database server, data or figures insertion into the table and data selection via Graphical User Interface. The selected data can be stored in NetCDF, HDF5, DataBase or TXT file formats and the figures can be available in PNG, JPG, JPNG, PDF or GIF file formats. The program was tested on Linux and Windows platforms with different JavaTM Development Kit. The MeteoRead is planned to be developed to visualizing the annual, seasonal, monthly, daily or hourly average value of the selected data and to use the functionality of the SQL database to calculate various mathematical and statistical correlations.

关键词： JavaTM Language MySQLTM Database Atmospheric Data Global Change

Investigation of heavy metals and lipid peroxidation level in the muscles of Clarias gariepinus from IBI,Gindin-Dorowa and D onga community rivers in Taraba State,Nigeria

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Toxicology Advances 2023年第3期5卷 33-37页

作者： Asuelimen Steve Osagie ale.Ebenezer Morayo Department of Biochemistry Faculty of Pure and Applied SciencesFederal University PMB 1020 Wukari200 Katsina-Ala RoadWukari 670101Nigeria

Heavy metals have harmful effects on human health,and exposure to these metals has been increased by industrial and anthropogenic activities and modern *** metals content of the liver tissues was determine d using Atomic Absorption Spectrophotometer method,while lipid peroxidation was carried *** metals analyzed include;lead(Pb),cadmium(Cd),zinc(Zn),Arsenic(As),and Mercury(Hg).The findings reveale. that the heavy metal Zinc(Zn)has high concentrations in the muscles of the fish species,the concentration of this heavy metal Zinc is high in River Gindin Dorowa th a n in River Ibi and River Donga shows less concentration of this heavy metal though it’s above WHO permissible *** reveale. that only Zn and Cd were present in the muscle from the three *** was found only in the liver from Gindin-Dorowa at the concentration of 0.017 mg/kg,which is not significant(Pale. that there is a negative relation between heavy metals and the effect of TBA on the cerebral tissues to protect or save aquatic habitat s of fish quality and aquatic life.

关键词： heavy metals lipid peroxidation Clarias gariepinus bioaccummulation

Evaluating Biomass of Juniper Trees (Juniperus pinchotii) from Imagery-Derived Canopy Area Using the Support Vector Machine Classifier

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Remote Sensing 2013年第2期2卷 181-192页

作者： Mustafa Mirik Sriroop Chaudhuri Brady Surber Srinivasulu ale.Robert James Ansley Texas A&M AgriLife Research (TAMAR) Vernon USA

Both temporal and spatial magnitude, structure, and distribution of rangeland aboveground biomass (AGB) are important inputs for many necessities, in particular for estimating terrestrial carbon amount, ecosystem productivity, climate change studies, and potential bioenergy uses. Much of the remote sensing research previously completed has focused on determining carbon stocks in forested ecosystems with little attention directed to estimate AGB amount in rangelands. Our objectives were to: 1) identify and delineate individual redberry juniper (Juniperus pinchotii) plants from surrounding live vegetation using the support vector machine method for classifying two-dimensional (2D) geospatial imagery with a 1-m spatial resolution at two sites;and 2) develop regression models relating imagery-derived and fieldmeasured single tree canopy area and diameter for dry AGB estimation. The regression results show that there were very close and significant relationships between field measured juniper plant AGB and canopy area derived from the image classification with r2 > 0.90. These results suggest that spectral reflectance recorded on 2D high resolution imagery is capable to assess and quantify AGB as a quick, repeatable, and unbiased method over large land areas.

关键词： Remote Sensing Geospatial Imagery Biomass Juniperus pinchoti Rangeland Bioenergy Terrestrial Carbon Budget

Studies on Heavy Metals Levels in Hepatic Tissues of Cat Fishes(Clarias gariepinus)from River Ibi,Donga and Gindin-Dorowa in Taraba State Nigeria,in Relation to key Enzyme of heme Biosynthetic Pathway

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Toxicology Advances 2023年第4期5卷 8-14页

作者： Ebenezer Morayo ale.Steve Osagie Asuelimen Department of Biochemistry Faculty of Pure and Applied SciencesFederal University PMB 1020 WukariWukari 670101Nigeria

Fishes are excellent markers of the extent of pollution from heavy metals in aquatic environments given that they are found at various levels of the food *** study aimed to investigate the bioaccumulation of heavy metals(Zn,Pb,Cd,As,and Hg)as well as the activity of delta-aminolevulinic acid dehydratase(δ-ALA-D)in the livers of cat fishes(Clarias gariepinus)collected from three rivers(Donga,Ibi and Gindin-Dorowa)in Taraba State,*** concentrations of heavy metals in the liver tissues were determined using an atomic absorption spectrophotometer in accordance with the method of AOAC(2019),while theδ-ALA-D activity was assayed using the method of Sassa(1982).Results reveale. that only Zn and As were present in the liver samples from the three *** was found only in the liver from Gindin-Dorowa at the concentration of 0.0012mg/kg which is not significant(P<0.05)when compared with other locations,while Hg and Cd were absent in all the liver *** liver sample from Gindin-Dorowa had the highest concentration of Zn(4.2500 mg/kg),followed by Ibi(3.2067 mg/kg),and Donga having the least(2.5500 mg/kg),which were all substantially(P<0.05)different from one ***,there was no significant(P<0.05)difference in the As composition of liver from Donga(0.0013 mg/kg),Ibi(0.0012 mg/kg)and Gindin-Dorowa(0.0010 mg/kg).The result ofδ-ALA-D activity showed that the highest enzymatic activity was found in the liver sample from Donga which has the least Zn and no Pb content,followed by Ibi *** validates the report that heavy metals impairδ-ALA-D ***,the concentrations of all metals in fish livers from all regions do not exceed the acceptable limits set by international law,making them safe for human consumption and possibly not having a negative impact on public *** there is little or no industrial activity in the studied locations,these levels may be consequent to low anthropogenic *** current situation should be sa

关键词： heavy metals bioaccumulation delta-aminolevulinic acid dehydratase Atomic Absorption Spectrophotometer Clarias gariepinus bioaccumulation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国电子竞技——在尴尬中点击鼠标

中国体育（中英文版） 2007年第4期 80-83页

作者： ale

2001年.WCG 世界电子竞技大赛进入中国.令中国国内的游戏爱好者们大开眼界。2003年11月,国家体育总局正式将电子竞技列为运动项目。2004年初,《电子竞技世界》栏目在中央五台遭遇禁播。如今.魔兽的 SKY、星际的苏昊,CS 的 wNv.他们让五... 详细信息

2001年.WCG 世界电子竞技大赛进入中国.令中国国内的游戏爱好者们大开眼界。2003年11月,国家体育总局正式将电子竞技列为运动项目。2004年初,《电子竞技世界》栏目在中央五台遭遇禁播。如今.魔兽的 SKY、星际的苏昊,CS 的 wNv.他们让五星红旗飘扬在电子世界之巅……从电子竞技运动在世界上以及中国开展的情况看.

关键词：电子竞技李晓峰运动项目苏昊世界之巅游戏爱好者竞技体育项目星际争霸国家体育总局体操项