70,044 research outputs found

    Electrical self-aligning connector

    Get PDF
    A self-aligning electrical connector device includes a receptacle component having a conically contoured interior and a plug component having a correspondingly contoured conical body receivable in the receptacle component. The plug component has a number of spaced conductive ring elements with a mating face and the receptacle component includes corresponding spaced conductive ring elements providing mating interface with the mating face of the ring elements of the plug component when connected to it. Each ring element of the receptacle component has several segmented portions which defect downwardly when the plug component is inserted. A biasing force is asserted against the face of the ring elements of the plug component providing positive electrical contact and connection between the ring elements of the components

    Getting on the E List: E-Mail Use in a Community of Service Provider

    Get PDF
    This case examines how a community of organizations providing service to people experiencing homelessness made use of an electronic mail list. Current economic conditions have encouraged organizations in various sectorsā€”including nonprofitsā€”that might normally compete for scarce resources to collaborate with one another to increase their chances of survival. One set of tools likely to be of value in such relationships includes various online discussion technologies. An examination of this communityā€™s email list use over a three-year period suggests a somewhat complex picture regarding technology use. More specifically, some issues both constrain and enable use. Additionally, seemingly basic and minimal uses of the list provided not only the greatest functionality for the users, but also led to several unanticipated consequences for those involved

    Classical Functional Bethe Ansatz for SL(N)SL(N): separation of variables for the magnetic chain

    Full text link
    The Functional Bethe Ansatz (FBA) proposed by Sklyanin is a method which gives separation variables for systems for which an RR-matrix is known. Previously the FBA was only known for SL(2)SL(2) and SL(3)SL(3) (and associated) RR-matrices. In this paper I advance Sklyanin's program by giving the FBA for certain systems with SL(N)SL(N) RR-matrices. This is achieved by constructing rational functions \A(u) and \B(u) of the matrix elements of T(u)T(u), so that, in the generic case, the zeros xix_i of \B(u) are the separation coordinates and the P_i=\A(x_i) provide their conjugate momenta. The method is illustrated with the magnetic chain and the Gaudin model, and its wider applicability is discussed.Comment: 14pp LaTex,DAMTP 94-1

    Embryo futures and stem cell research: The management of informed uncertainty

    Get PDF
    This article is available open access and is distributed under a Creative Commons license (http://creativecommons.org/licenses/by/3.0/). Copyright @ 2011 The Authors.In the social worlds of assisted conception and stem cell science, uncertainties proliferate and particular framings of the future may be highly strategic. In this article we explore meanings and articulations of the future using data from our study of ethical and social issues implicated by the donation of embryos to human embryonic stem cell research in three linked assisted conception units and stem cell laboratories in the UK. Framings of the future in this field inform the professional management of uncertainty and we explore some of the tensions this involves in practice. The bifurcation of choices for donating embryos into accepting informed uncertainty or not donating at all was identified through the research process of interviews and ethics discussion groups. Professional staff accounts in this study contained moral orientations that valued ideas such as engendering patient trust by offering full information, the sense of collective ownership of the National Heath Service and publicly funded science and ideas for how donors might be able to give restricted consent as a third option.The Wellcome Trus

    Donation of 'spare' fresh or frozen embryos to research: Who decides that an embryo is 'spare' and how can we enhance the quality and protect the validity of consent?

    Get PDF
    This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited - Copyright @ The Author 2012.This paper analyses elements of the legal process of consent to the donation of ā€˜spareā€™ embryos to research, including stem-cell research, and makes a recommendation intended to enhance the quality of that process, including on occasion by guarding against the invalidity of such consent. This is important in its own right and also so as to maximise the reproductive treatment options of couples engaged in in vitro fertilisation (IVF) treatment and to avoid possible harms to them. In Part 1, with reference to qualitative data from three UK IVF clinics, we explore the often delicate and contingent nature of what comes to be, for legal purposes, a ā€˜spareā€™ embryo. The way in which an embryo becomes ā€˜spareā€™, with its implications for the process of consent to donation to research, is not addressed in the relevant reports relating to or codes of practice governing the donation of embryos to research, which assume an unproblematic notion of the ā€˜spareā€™ embryo. Significantly, our analysis demonstrates that there is an important and previously unrecognised first stage in the donation of a ā€˜spareā€™ embryo to research, namely: consent to an embryo being ā€˜spareā€™ and so, at the same time, to its disuse in treatment. This is not explicitly covered by the Human Fertilisation and Embryology (HFE) Act 1990, as amended by the HFE Act 2008. Having identified this important initial stage in the process of consent to the donation of a ā€˜spareā€™ embryo to research in conclusion to Part 1, in Part 2 we analyse the idea of consent to an embryo's disuse in treatment on the basis that it is ā€˜spareā€™ with reference to the legal elements of consent, namely information as to nature and purpose, capacity, and voluntariness. We argue that there are in fact three related consent processes in play, of which the principal one concerns consent to an embryo's disuse in treatment. If the quality of this first consent is compromised, in turn this will impact on the quality of the consent to the donation of that ā€˜spareā€™ embryo to research, followed by the quality of consent to future cycles of assisted reproduction treatment in the event that these are needed as a result of a donation decision. The analysis overall is of central relevance to the debate as to whether, and if so when, it should be permissible to request the donation of fresh embryos for research, as opposed to those that have been frozen and, for instance, have reached the end of their statutory storage term. This has a particular bearing on the donation of embryos to stem-cell research since there is a debate as to whether fresh embryos are most useful for this.This work is funded by the Wellcome Trust Biomedical Ethics Programme, Project Grant No 081414

    Halogenation of microcapsule walls

    Get PDF
    Procedure for halogenation of confining walls of both gelatin and gelatin-phenolic resin capsules is similar to that used for microencapsulation. Ten percent halogen content renders capsule wall nonburning; any higher content enhances flame-retardant properties of selected internal phase material. Halogenation decreases permeability of wall material to encapsulated materials

    The Hetu'u Global Network: Measuring the Distance to the Sun Using the June 5th/6th Transit of Venus

    Full text link
    In the spirit of historic astronomical endeavors, we invited school groups across the globe to collaborate in a solar distance measurement using the rare June 5/6th transit of Venus. In total, we recruited 19 school groups spread over 6 continents and 10 countries to participate in our Hetu'u Global Network. Applying the methods of French astronomer Joseph-Nicolas Delisle, we used individual second and third Venus-Sun contact times to calculate the distance to the Sun. Ten of the sites in our network had amiable weather; 8 of which measured second contact and 5 of which measured third contact leading to consistent solar distance measurements of 152+/-30 million km and 163+/-30 million km respectively. The distance to the Sun at the time of the transit was 152.25 million km; therefore, our measurements are also consistent within 1sigma of the known value. The goal of our international school group network was to inspire the next generation of scientists using the excitement and accessibility of a rare astronomical event. In the process, we connected hundreds of participating students representing a diverse, multi-cultural group with differing political, economic, and racial backgrounds.Comment: 19 pages; 7 Figures; 1 Table; Accepted for publication in Astronomy Education Review (AER) For more information see http://www.das.uchile.cl/~drodrigu/easter/index_en.htm
    • ā€¦
    corecore