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In crustaceans, the male sexual dif ferentiation and maintenance are specially regulated by androgenic gland(AG). However, little is known about the genes involved in the regulation process.RNA-Seq was performed on AG with ejaculatory duct(AG_ED) and ejaculatory duct(ED) as control in Eriocheir sinensis, one of the most important economic and ?shery crabs with typically sex dimorphism. A total of 925 unigenes were identi?ed as dif ferentially expressed genes(DEGs) and the expression of nine genes randomly selected was con?rmed by qRT-PCR. 667 unigenes were up-regulated in AG_ED, being supposed to be AG preferential genes. Among them, the full length of i nsulin-like androgenic gland factor( IAG) cDNA named as Es-IAG was obtained as a logo gene of AG, which together with the genes i nsulin-like receptor( INR), and s ingle insulin binding domain protein( SIBD), might constitute the sex regulation pathway. Several sex related genes were identi?ed, and their function will have to be investigated. Also,the identi?cation of j uvenile hormone epoxide hydrolase 1( JHEH1), ecdysteroid 22-hydroxylase( DIB) and e cdysone receptor( ECR) preliminarily clari?ed the molecular regulation mechanism of eyestalk-AG-testis axis, which plays important roles in molting and reproduction. The results will enhance our understanding for the molecular basis of the AG involved in male sex regulation in crabs. 相似文献
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Jean S. Kane Philip J. Potts Thomas Meisel Michael Wiedenbeck 《Geostandards and Geoanalytical Research》2007,31(3):285-288
The International Association of Geoanalysts (IAG) published a protocol for the certification of reference materials in close accord with the International Organisation for Standardisation (ISO) guidelines (Kane et al. 2003). This article supplements that protocol, providing additional discussion of best approaches for pre-selecting laboratories for participation in certification projects. This discussion also makes a distinction between inter-laboratory certifications, where n = 15 is the general standard, and expert laboratory certifications, where a much smaller number of laboratories will be deemed qualified to provide data of the quality needed for certification. 相似文献
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The International Organisation for Standardisation (ISO) has published many guides, or technical standards, of great value to analytical geochemists. Two of particular importance are Guide 33 (Uses of Certified Reference Materials) and Guide 35 (Certification of Reference Materials). Both were first developed in the 1980s and undergo regular review and updating by the Reference Materials Committee (REMCO) that operates within ISO. Recent revisions have focused on adding statistical rigour to both guides. Although this offers significant advantages for use by professional metrologists, there are consequent issues of comprehension by the analytical chemists who in fact have the greatest need of them. A major focus of Guide 35 is the development of reference material uncertainties that are in full compliance with the Guide on Measurement Uncertainty (GUM), jointly issued by ISO, IUPAC and others. Guide 35 details handling of uncertainty due to (1) degradation on the shelf and in transport, (2) sample heterogeneity and (3) inter‐method and inter‐laboratory bias, as well as within‐laboratory repeatability. The International Association of Geoanalysts has developed a protocol for reference material certification that applies Guide 35 to the specific needs of the geoanalytical community. The approach being taken by the IAG in developing GUM‐compliant uncertainties for its certified values is presented. Recommendations made in Guide 33 for how a laboratory should compare its own results with certified values in assessing laboratory accuracy are outlined. Additionally, the subject of misusing reference materials is discussed. The apparent misuse occurs because so few CRMs exist that meet critical measurement needs of geoanalytical laboratories and that also meet the rigorous metrological demands of the latest editions of the ISO Guides. All of the focus of the IAG certification programme has been to undertake certifications that would fill gaps in CRM availability and thus serve to limit this misuse. 相似文献
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Reference materials (RM) are essential to achieve traceability of measurements. Specific uses of RM in analytical laboratories are the validation of methods, the calibration of instruments, the quality control and the demonstration of proficiency. This paper describes the certification of a new geochemical reference material, named BRP-1 (Basalt Ribeirão Preto), and acts as the certificate of analysis for this RM. The rock sample was crushed and pulverised at the USGS (Denver, USA), homogenised and split into 1920 bottles, with 55 g each. BRP-1 was transported back to Brazil and the homogeneity between and within bottles was assessed to demonstrate sufficient homogeneity for certification. The chemical characterisation was performed by twenty-five laboratories. Each laboratory received two bottles of BRP-1 and one of BCR-2 (Basalt Columbia River) used for quality control (QC). Reference values and uncertainties were calculated for forty-four constituents of BRP-1, following ISO Guide 35 recommendations and the IAG Protocol. The calculation of each reference value included data of proven traceability from at least ten laboratories using two or more analytical techniques and the uncertainties combines the characterisation and between bottle homogeneity contributions. 相似文献
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GGOS和大地测量技术进展 总被引：8，自引：4，他引：4
在2005年8月澳大利亚凯恩斯(Cairns)国际大地测量协会(IAG)科学大会上,全球大地测量观测系统(GlobalGeodeticObservingSystem,简为GGOS)作为这次科学大会一个重要议题成为一个热点问题,也成为未来大地测量学科进展的一个风向标。本文较为全面地介绍了GGOS的背景、目标、任务和科学原理等,结合GGOS在全球动力系统观测中的应用构想,说明了GGOS与其他地球观测系统越来越紧密的联系和相互促进的发展趋势。除此之外,本文还简要介绍了这次科学大会其他领域如大地坐标框架和卫星重力等领域的最新进展。 相似文献
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国际大地测量和地球物理联合会2003年日本大会札记 总被引：1，自引：2，他引：1
简要介绍了IUGG2003年日本札幌大会的概况,IAG(2003-2007)的组织机构和它准备实施的“全球组合观测系统”(IGGOS)的情况,并将参加学术会议的几点收获做扼要介绍。其中主要包括:邻近国家大地坐标系统和坐标框架的更新和现代化;卫星重力学,如CHAMP,GRACE所取得的进展;和GPS数据处理方法的改善等。 相似文献
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Jean S. Kane 《Geostandards and Geoanalytical Research》2004,28(1):53-80
The International Association of Geoanalysts (IAG) has certified a slate sample, OU-6, for twelve major and minor constituents, as well as thirty-five trace elements through an interlaboratory programme conducted in close compliance with the International Organization for Standardization (ISO) Guide 35 (1989). Laboratories were qualified for participation in the certification programme, based on their performance in the prior analysis of OU-6 as a proficiency test material. Thirty laboratories provided data for the certification, though not for each constituent that was certified. Certification criteria included a means of establishing traceability for the certification data, generally through concurrent analysis of the existing Geological Survey of Japan reference material JSl-1, agreement of results between laboratories and methods, and a minimum of data rejection (4% rejection rate for OU-6 data and 6% for JSl-1 data), preferably for well-understood technical reasons only. Information values are provided for an additional eight constituents where certification criteria were not met. Uncertainties developed in accordance with the "Guide on Uncertainty in Measurement" (Eurachem 2000) and representing the 95% confidence interval of the certified and information values are reported for all fifty five constituents. The material is currently available in 40 g units for distribution by the IAG. Supply is anticipated to last about ten years. 相似文献
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走向21世纪的国际大地测量和地球物理联合会--第22届IUGG大会综述 总被引：6，自引：0，他引：6
文章介绍了国际大地测量和物理联合会（IUG）的宗旨、构成及第22届IUGG的讨论议题,并提供国际大地测量协会（IAG）的有关情况和本次会议通过的决议内容。 相似文献
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王静瑶 《大地测量与地球动力学》1993,(4)
本文介绍了近期国际大地测量协会的五个学术分部(定位,空间先进技术,重力场测定,综合理论与方法,地球动力学)的专题研究、主要研究目标和计划,对其中有关现代地壳运动和地球动力学研究的重要专题作了详细介绍。 相似文献
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Klaus Peter Jochum Jacinta Enzweiler Regina Mertz-Kraus Xiaohong Wang 《Geostandards and Geoanalytical Research》2010,34(4):353-385
This review gives an overview of the literature on reference materials of geochemical and environmental interest for the two-year period 2008–2009. Reference materials play an increasingly important role in all fields of geoanalytical research. This is demonstrated by the large number of publications containing data on reference materials. Although many reference materials exist, there is still a great need for certified samples, so-called delta zero materials for stable isotopic work and homogeneous microanalytical reference materials. This review focuses on six topics: developments of certification processes of reference materials mainly postulated in ISO guidelines and the IAG protocol, new developments of the GeoReM database, investigations of powdered rock reference materials, Chinese reference materials published in Chinese journals, microanalytical reference materials and isotopic reference materials. 相似文献
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