5,455 research outputs found
Applications, Potential Problems and a Suggested Policy for Institutional E-Print Archives
EPrints archives and similar archives promise many benefits for academics and their institutions, but there are complications in trying to solve too many problems at once. We describe the potential uses for an institutional archive running either the GNU EPrints software or software intended to provide similar functionality and how those applications may complement or interfere with each other. We then discusses policy decisions which should be made when implementing an archive and suggest a possible policy based on our own experience at Southampton University where the Electronics and Computer Science Department has been running an archive and database of our publications since 1998 and has provided software and assistance to many other institutions setting up a variety of electronic archives
What Should We Learn From Early Hemodialysis Allocation About How We Should Be Using ECMO?
Early hemodialysis allocation deliberations should inform our current considerations of what constitutes reasonable uses of extracorporeal membrane oxygenation. Deliberative democracy can be used as a strategy to gather a plurality of views, consider criteria, and guide policy making
Changes in Dry State Hemoglobin over Time Do Not Increase the Potential for Oxidative DNA Damage in Dried Blood
BACKGROUND: Hemoglobin (Hb) is the iron-containing oxygen transport protein present in the red blood cells of vertebrates. Ancient DNA and forensic scientists are particularly interested in Hb reactions in the dry state because both regularly encounter aged, dried bloodstains. The DNA in such stains may be oxidatively damaged and, in theory, may be deteriorated by the presence of Hb. To understand the nature of the oxidative systems potentially available to degrade DNA in the presence of dried Hb, we need to determine what molecular species Hb forms over time. These species will determine what type of iron (i.e. Fe(2+)/Fe(3+)/Fe(4+)) is available to participate in further chemical reactions. The availability of "free" iron will affect the ability of the system to undergo Fenton-type reactions which generate the highly reactive hydroxyl radical (OH*). The OH* can directly damage DNA. METHODOLOGY/PRINCIPAL FINDINGS: Oxygenated Hb (oxyHb) converts over time to oxidized Hb (metHb), but this happens more quickly in the dry state than in the hydrated state, as shown by monitoring stabilized oxyHb. In addition, dry state oxyHb converts into at least one other unknown species other than metHb. Although "free" iron was detectable as both Fe(2+) and Fe(3+) in dry and hydrated oxyHb and metHb, the amount of ions detected did not increase over time. There was no evidence that Hb becomes more prone to generating OH* as it ages in either the hydrated or dry states. CONCLUSIONS: The Hb molecule in the dried state undergoes oxidative changes and releases reactive Fe(II) cations. These changes, however, do not appear to increase the ability of Hb to act as a more aggressive Fenton reagent over time. Nevertheless, the presence of Hb in the vicinity of DNA in dried bloodstains creates the opportunity for OH*-induced oxidative damage to the deoxyribose sugar and the DNA nucleobases
Early experiences of computerâaided assessment and administration when teaching computer programming
This paper describes early experiences with the Ceilidh system currently being piloted at over 30 institutions of higher education. Ceilidh is a courseâmanagement system for teaching computer programming whose core is an autoâassessment facility. This facility automatically marks students programs from a range of perspectives, and may be used in an iterative manner, enabling students to work towards a target level of attainment. Ceilidh also includes extensive courseâadministration and progressâmonitoring facilities, as well as support for other forms of assessment including shortâanswer marking and the collation of essays for later handâmarking. The paper discusses the motivation for developing Ceilidh, outlines its major facilities, then summarizes experiences of developing and actually using it at the coalâface over three years of teaching
Antioxidant properties of caeruloplasmin towards iron- and copper-dependent oxygen radical formation
AbstractThe antioxidant activity of caeruloplasmin can be mainly ascribed to its ferroxidase activity which effectively inhibits ferrous ion-stimulated lipid peroxidation and ferrous ion-dependent formation of hydroxyl radicals in the Fenton reaction. In addition, caeruloplasmin can prevent copper ions from stimulating lipid peroxidation
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