检索结果-南通市图书馆

法医检案中常见客体上接触性DNA检验效果比较

在线全文

学校读者我要写书评

暂无评论

绍兴文理学院学报 2024年第2期44卷 78-87页

作者：范光耀鞠天格 WUO nixon AUSTIN 彭长秀绍兴文理学院医学院浙江绍兴312000 绍兴文理学院生命与环境科学学院浙江绍兴312000

目的:接触性DNA在鉴定犯罪嫌疑人身份方面起着至关重要的作用.因客体表面材质的差异,嫌疑人接触过的某些客体上DNA常难于保留而不易检测.若能对不同种类客体的接触性DNA检验效果进行合理预判,对后续的法医基因分型将至关重要.材料:模拟2... 详细信息

目的:接触性DNA在鉴定犯罪嫌疑人身份方面起着至关重要的作用.因客体表面材质的差异,嫌疑人接触过的某些客体上DNA常难于保留而不易检测.若能对不同种类客体的接触性DNA检验效果进行合理预判,对后续的法医基因分型将至关重要.材料:模拟24种不同客体上的接触性DNA.方法:双拭子法采集DNA,microcon■离心浓缩,GlobalFilter■扩增试剂盒基因分型和Quantifiler■Duo试剂盒定量DNA.分别比较24种客体和进一步归类五种材质上的接触性DNA的平均峰高度(APH)、平均峰面积(APA)和等位基因检出率.结果:旋转式开关的检验效果最好,眼镜框架、塑料袋封条和笔筒次之.塑料类客体表面上的DNA检出成功率优于玻璃、金属、木质和橡胶类客体.结论:不同类客体之间的接触性DNA检验效果存在差异.

关键词：法医学接触性DNA 客体短串联重复 DNA分型图谱

在线全文

学校读者我要写书评

暂无评论

深海环境海洋生态系统监测与修复新技术

Engineering 2024年第3期34卷 195-211页

作者： Jacopo Aguzzi Laurenz Thomsen Sascha Flögel Nathan J.Robinson Giacomo Picardi Damianos Chatzievangelou nixon Bahamon Sergio Stefanni Jordi Grinyó Emanuela Fanelli Cinzia Corinaldesi Joaquin Del Rio Fernandez marcello Calisti Furu mienis Elias Chatzidouros Corrado Costa Simona Violino michael Tangherlini Roberto Danovaro Instituto de Ciencias del mar(ICm-CSIC) Barcelona 08003Spain Stazione Zoologica Anton Dohrn Naples 80121Italy University of Gothenburg Göteborg 40530Sweden GEOmAR Helmholtz Centre for Ocean Research Kiel 24148Germany Fundación Oceanogràfic de la Comunitat Valenciana Valencia 46013Spain Royal Netherlands Institute for Sea Research(NIOZ) Den Burg Texel 1790 ABNetherlands Polytechnic University of marche(UNIVPm) Ancona 60131Italy SARTI-mAR of the Universitat Politecnica de Catalunya(UPC) Vilanova i la Geltrú08800Spain Lincoln Institute for Agri-food Technology University of LincolnLincoln LN22LGUK Engitec Systems International Limited Limassol 3083Cyprus Consiglio per la Ricerca in Agricoltura e L’analisi Dell’economia Agraria(CREA) Centro di Ricerca Ingegneria e Trasformazioni AgroalimentariMonterotondo 00015Italy

The United Nations(UN)’s call for a decade of“ecosystem restoration”was prompted by the need to address the extensive impact of anthropogenic activities on natural *** ecosystem restoration is increasingly necessary due to increasing habitat degredation in deep waters(>200 m depth).At these depths,which are far beyond those accessible by divers,only established and emerging robotic platforms such as remotely operated vehicles(ROVs),autonomous underwater vehicles(AUVs),landers,and crawlers can operate through manipulators and multiparametric sensor arrays(e.g.,optoacoustic imaging,omics,and environmental probes).The use of advanced technologies for deep-sea ecosystem restoration can provide:①high-resolution three-dimensional(3D)imaging and acoustic mapping of substrates and key taxa,②physical manipulation of substrates and key taxa,③real-time supervision of remote operations and long-term ecological monitoring,and④the potential to work ***,we describe how robotic platforms with in situ manipulation capabilities and payloads of innovative sensors could autonomously conduct active restoration and monitoring across large spatial *** expect that these devices will be particularly useful in deep-sea habitats,such as①reef-building cold-water corals,②soft-bottom bamboo corals,and③soft-bottom fishery resources that have already been damaged by offshore industries(i.e.,fishing and oil/gas).

关键词： Ecosystem restoration Robotic manipulation Acoustic tracking Fishery resources Artificial reefs

Electrical and non-linear optical studies on electrospun ZnO/BaO composite nanofibers

在线全文

学校读者我要写书评

暂无评论

Frontiers of materials Science 2012年第1期6卷 69-78页

作者： G.nixon SAmUEL VIJAYAKUmAR m.RATHNAKUmARI P.SURESHKUmAR Department of Physics R.M.K.Engineering CollegeR.S.M.NagarKavaraipettai 601206India materiais Research Centre Department of PhysicsVelammal Engineering CollegeChennai 600066India

Nanocapacitors and nonvolatile ferroelectric random access memories require nanoscale thin film coatings with ferroelectric properties. One dimensional ferroelectric nanofibers are used in ferroelectric memory devices owing to the fact that decrease of the dimensionality of the memory device elements will reduce the addressing and appreciably increase the storage capacity, Novel ZnO/BaO nanocomposite fibers exhibiting ferroelectric properties have been prepared in the form of non-woven mesh by electrospinning the sol derived from the sol-gel route, Thin cylindrical nanofibers of average diameter 100 nm have been obtained and their morphology is confirmed by SEm and AFm images. In the electrospinning process, the effect of the working distance on the fiber morphology was studied and it showed that working distance between 11 and 15 cm can produce fibers without beads and the decrease in working distance in this range increases the fiber diameter. Powder XRD was used to identify the phases and EDX analysis confirmed the presence of ZnO/BaO. Dielectric and non-linear optical properties have also been studied. The dielectric studies showed that ZnO/BaO composite nanofibers undergo a phase transition from ferroelectric to paraelectric at 323 K.

关键词： nanocomposite fiber sol-gel process dielectric property non-linear opticalproperty ferroelectric property

The 12th International Symposium on Spermatology

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2015年第4期17卷 519-520页

作者： R John Aitken Jim m Cummins Brett nixon Priority Research Centre in Reproductive Science Discipline of Biological Sciences and HunterMedical Research Institute University of NewcastleNSW 2308 Australia Division of Veterinary andBiomedical Sciences Murdoch University MurdochWA. Australia.

The 12th International Symposium of Spermatology continued the excellent tradition of this meeting since its inception in 1969 when the first Symposium was held in Italy under the Chairmanship of Professor Baccio Baccetti. This unique Symposium is held every 4 years and serves as a beacon for sperm cell biologists from all over the world, regardless of which species, animal or plant, they are working on. This willingness to embrace the fundamental biology of this distinctive cell type without species limitations is one of the hallmarks of this Symposium. For sperm biologists - it is our Olympics. The meeting in Newcastle, NSW brought together around 300 biologists from more than 22 different countries covering North and South America, Africa, Europe, Asia and Australia. Given the considerable distances and high cost involved in travelling to the East Coast of NSW, this was an outstanding outcome. The Symposium featured a series of 31 plenary lectures culminating in the prestigious Thaddeus mann memorial Lecture, which was delivered with typical grace and brilliance by Professor masaru Okabe.

关键词： International Symposium Spermatology

Are sperm capacitation and apoptosis the opposite ends of a continuum driven by oxidative stress？

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2015年第4期17卷 633-639页

作者： Robert J Aitken mark A Baker Brett nixon Priority Research Centre in Reproductive Science Discipline of Biological Sciences and Hunter Medical Research Institute University of Newcastle NSW 2308 Australia.

This chapter explores the possibility that capacitation and apoptosis are linked processes joined by their common dependence on the continued generation of reactive oxygen species （ROS）. According to this model capacitation is initiated in spematozoa following their release into the female reproductive tract as a consequence of intracellular ROS generation, which stimulates intracellular cAmP generation, inhibits tyrosine phosphatase activity and enhances the formation of oxysterols prior to their removal from the sperm surface by albumin. The continued generation of ROS by capacitating populations of spermatozoa eventually overwhelms the limited capacity of these cells to protect themselves from oxidative stress. As a result the over-capacitation of spermatozoa leads to a state of senescence and the activation of a truncated intrinsic apoptotic cascade characterized by enhanced mitochondrial RO$ generation, lipid peroxidation, motility loss, caspase activation and phosphatidylserine externalization. The latter may be particularly important in instructing phagocytic leukocytes that the removal of senescent, moribund spermatozoa should be a silent process unaccompanied by the generation of proinflammatory cytokines. These observations reveal the central role played by redox chemistry in defining the life and death of spermatozoa. A knowledge of these mechanisms may help us to engineer novel solutions to both support and preserve the functionality of these highly specialized cells.

关键词： apoptosis reactive oxygen species sperm capacitation

Friction surfacing of AISI 316 over mild steel: A characteriation study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2018年第4期14卷 306-312页

作者： R.George Sahaya nixon B.S.mohanty R.Sathish Department of mechanical Sathyabama University Department of mechanical Engineering St.Joseph's College of Engineering Department of mechanical Engineering SRM Easwari

An attempt has been made with overlaying of stain-less steel on mild steel by the technique of friction surfacing. This investigation elaborates the excellence acquired by different combination of the process parameters used in friction surfacing specifically traverse speed of the cross slide, speed of rotation of the spindle and the uniaxial compressive load. Excellent overlaying has been obtained amongst the chosen materials. To which, the coating can be done with various set of process parameters. It has been observed that the bond strength of the coating was found to be at a maximum of 502 mPa by ram tensile *** upon this results the surface methodology was characterized with scanning electron *** authenticating the results, the coated specimen was subjected to salt spray test. The bonding microstructure was characterized using optical microscopy and X-ray diffraction. Corrosion resistance of surfaced coatings was found to be more inferior to that of mechtrode material and greater with the substrate.

关键词： Friction surfacing Rotational speed Traverse speed Axial load Salt spray test microstructure XRD analysis Ram tensile test

TRACE mETALS IN VANDA LAKE IN ANTARCTICA——A VERTICAL mIGRATION mODEL OF TRACE mETALS IN CLOSED BASIN

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 1992年第11期35卷 1397-1408页

作者：于昇松 W.J.GREEN P.A.nixon Institute of Salt Lakes Academia Sinica Xining 810008 PRC School of Interdisciplinary Studies Miami University Ohio U. S. A.

Vanda Lake, a typical dimictic CaCl_2 type salt lake, is located in the Wright Valley inAntarctica. Based on the chemical and physical features of the salt lake water, the authorsdiscussed the vertical geochemical distribution of Fe, mn, Pb, Cr, Cu, Co, Ni, Cd in the lake,and their vertical migration in lake waters, and have tried to set up a model of vertical mi-gration of these trace elements in the water of a closed chloride type salt lake.

关键词： Antarctica trace elements ion activity product

Cellular mechanisms regulating sperm-zona pellucida interaction

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2011年第1期13卷 88-96页

作者： Andrew T Reid Kate Redgrove R John Aitken Brett nixon Reproductive Science Group Discipline of Biological Sciences School of Environmental and Life Sciences University of Newcastle Callaghan NSW 2308 Australia ARC Centre of Excellence in Biotechnology and Development Discipline of Biological Sciences School of Environmental and Life Sciences University of Newcastle CaUaghan NSW 2308 Australia

For mammalian spermatozoa to exhibit the ability to bind the zona pellucida （ZP） they must undergo three distinct phases of maturation, namely, spermatogenesis （testis）, epididymal maturation （epididymis） and capacitation （female reproductive tract）. An impressive array of spermatozoa surface remodeling events accompany these phases of maturation and appear critical for recognition and adhesion of the outer vestments of the oocyte, a structure known as the ZP. It is becoming increasingly apparent that species-specific zona adhesion is not mediated by a single receptor. Instead, compelling evidence now points toward models implicating a multiplicity of receptor-ligand interactions. This notion is in keeping with emerging research that has shown that there is a dynamic aggregation of proteins believed to be important in sperm-ZP recognition to the regions of sperm that mediate this binding event. Such remodeling may in turn facilitate the assembly of a multimeric zona recognition complex （mZRC）. Though formation of mZRCs raises questions regarding the nature of the block to polyspermy, formation and assembly of such a structure would no doubt explain the strenuous maturation process that sperm endure on their sojourn to functional maturity.

关键词： capacitation fertilization spermatozoa sperm-zona pellucida interaction

Role of the epididymis in sperm competition

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2007年第4期9卷 493-499页

作者： Russell C. Jones Jean-Louis Dacheux Brett nixon Heath W. Ecroyd Discipline of Biological Sciences University of Newcastle Callaghan 2308 Australia UmR INRA-CNRS 6073 Physiologie de la Reproduction et des Comportements Nouzilly 37380 France Department of Chemistry University of Adelaide Adelaide 5005 Australia

Although it is generally understood that the testes recruited kidney ducts for reproductive function during the evolution of vertebrates, little is understood of the biological significance of the adaptation. In the context of the evolution of the mammalian epididymis, this report provides evidence that a major role of the epididymis is to enhance a male＇s chance of achieving paternity in a competitive mating system. A unique example of sperm cooperation in monotremes is used as evidence that the epididymis produces sperm competition proteins to form groups of 100 sperm into bundles that have a forward motility nearly thrice that of individual spermatozoa. As it required 3-h incubation in vitro under capacitation conditions to release motile sperm from the bundles, it is suggested that the monotremes provide an example of capacitation that is quite different from capacitation in higher mammals. It is suggested that variation between species in the intensity of sperm competition could explain the variation that occurs between species in the amount of post-testicular sperm maturation and storage in the epididymis, an explanation of why the human epididymis does not play as important a role in reproduction as the epididymis of most mammals. （Asian J Androl 2007 July; 9： 493-499）

关键词： epididymis sperm maturation sperm storage capacitation sperm competition sperm cooperation