1,928 research outputs found
Wire Scanner Motion Control Card
Scientists require a certain beam quality produced by the accelerator rings at CERN. The discovery potential of LHC is given by the reachable luminosity at its interaction points. The luminosity is maximized by minimizing the beam size. Therefore an accurate beam size measurement is required for optimizing the luminosity. The wire scanner performs very accurate profile measurements, but as it can not be used at full intensity in the LHC ring, it is used for calibrating other profile monitors. As the current wire scanner system, which is used in the present CERN accelerators, has not been made for the required specification of the LHC, a new design of a wire scanner motion control card is part of the LHC wire scanner project. The main functions of this card are to control the wire scanner motion and to acquire the position of the wire. In case of further upgrades at a later stage, it is required to allow an easy update of the firmware, hence the programmable features of FPGAs will be used for this purpose. The FPGAs will act as the control unit of the system. As the LHC has two separate vacuum chambers for the two counter rotating proton-beams, a wire scanner is needed for both the horizontal and vertical beam profile measurement. One motion control card is expected to control two wire scanners. The position of the wires must be acquired within a certain accuracy to meet the specification set for the LHC. In order to obtain the correct beam profile, the position acquisition must be well synchronized with the acquisition of the beam density. The values have to be stored in a memory, which is readable through the VME64x-bus
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An Examination Of The Uses To Which Time As A Formal Principle Is Employed In Selected Works Of Joseph Conrad, James Joyce, And Virginia Woolf
The following study examines the way in which a preoccupation with time is reflected in selected works of Conrad, Joyce and Virginia Woolf.
The first part of the Conrad section serves as an introduction to time in the narrative, by examining the assumptions underlying the time scheme of the Victorian novel. Conrad's use of the time shift and of the 'unreliable narrator' in Heart of Darkness and Lord Jim are then considered as devices for questioning those assumptions and advancing a more complex notion of the individual's sense of identity. The last part of this section examines Conrad's notion of 'destiny', particularly as it relates to his use of the time shift in Nostromo.
The study next focuses on Joyce's use of the 'epiphany' and traces its employment as an 'arrested moment' in Dubliners to its function as a moment of heightened awareness within consciousness in A Portrait of the Artist as a Young Man. Then, both the Portrait and Ulysses are considered separately as manifesting a vivid sense of time through the consciousness of Bloom and Stephen Dedalus. This section concludes with the argument put forward that n the relationship between Ulysses and its Homeric counterpart is to be sought in the identification of the artist with his work. Hence Ulysses is a celebration of the creative imagination throughout history.
In the Virginia Woolf section, the first part examines her atomistic notion of experience as it relates to personal identity, and sees her argument with the "materialists" enacted in Mrs. Dalloway and To the Lighthouse in the conflict of characters. The second part contrasts external representations of time in these novels with subjective time in the flux of consciousness. The last part of the section looks at the way in which certain unifying patterns in the novel are related to
Virginia Woolf's "moments of being".
Finally, the Conclusion briefly examines the way in which these writers manipulate language and form in order to give the reader a more than usual awareness of the text
For Better, For Worse: The Effect of Maternity Leave Policy on Divorce Rates
Prior to 1993, maternity leave legislation in the United States varied from state to state. The implementation of the Family and Medical Leave Act (FMLA) thus created a “natural experiment” via which we can study the effect of the law on divorce across states
Returns, Volatility and Liquidity on the ASX: Undisclosed vs. Disclosed Limit Orders
This paper investigates the information content of the two types of limit orders on the Australian Stock Exchange ASX: undisclosed orders (ULOs) and limit orders. Given the large order quantity contained in ULOs, we attempt to examine the impact of ULO submissions, cancellations and executions on price changes and volatility over differing intervals within a day. Motivation is generated by the ASX decision to abolish the use of ULOs in favour of iceberg orders. Intraday analysis shows that the impact of both ULO and disclosed order submissions are no longer than one day. ULO buying/selling order submissions at the best bid/ask price increase/decrease returns and price volatility significantly more than disclosed orders. The cancellations of ULOs cause significantly larger price volatility than disclosed limit order cancellations. Compared with disclosed limit order submissions, there is an increase in liquidity from the significantly reduced spread upon DLO submissions.Intraday effects, Return volatility, Undisclosed limit orders
Can guidelines improve referral to elective surgical specialties for adults? A systematic review
Aim To assess effectiveness of guidelines for referral for
elective surgical assessment.
Method Systematic review with descriptive synthesis.
Data sources Medline, EMBASE, CINAHL and Cochrane
database up to 2008. Hand searches of journals and
websites.
Selection of studies Studies evaluated guidelines for
referral from primary to secondary care, for elective
surgical assessment for adults.
Outcome measures Appropriateness of referral (usually
measured as guideline compliance) including clinical
appropriateness, appropriateness of destination and of
pre-referral management (eg, diagnostic investigations),
general practitioner knowledge of referral
appropriateness, referral rates, health outcomes and
costs.
Results 24 eligible studies (5 randomised control trials,
6 cohort, 13 case series) included guidelines from UK,
Europe, Canada and the USA for referral for
musculoskeletal, urological, ENT, gynaecology, general
surgical and ophthalmological conditions. Interventions
varied from complex (“one-stop shops”) to simple
guidelines. Four randomized control trials reported
increases in appropriateness of pre-referral care
(diagnostic investigations and treatment). No evidence
was found for effects on practitioner knowledge. Mixed
evidence was reported on rates of referral and costs
(rates and costs increased, decreased or stayed the
same). Two studies reported on health outcomes finding
no change.
Conclusions Guidelines for elective surgical referral can
improve appropriateness of care by improving prereferral
investigation and treatment, but there is no
strong evidence in favour of other beneficial effects
Managing emergencies in primary care: does real-world simulation-based training have any lasting impact?
General Practitioners (GPs) have a responsibility to provide prompt and effective care when attending to life threatening emergencies in their GP surgeries. Primary care staff undertake mandatory, annual basic life support training. However, most emergencies are peri-arrest situations, and this is an area where GPs lack confidence and competence [1, 2]. The importance of effective, early intervention in peri-arrest scenarios was highlighted by the NCEPOD report “Time to Intervene (2012)” [3]. This report suggested that better early assessment and intervention may have prevented progression to cardiorespiratory arrest. GPs need to be equipped to manage ‘time critical’ emergencies, particularly as GP surgeries are deemed a place of safety and 999 ambulances can be redirected to other emergencies, thereby delaying transfer to secondary care for patients in GP settings. In previous work, we demonstrated that GPs’ confidence in managing time critical emergencies was initially low, and significantly improved immediately after attending ‘real-world’, simulation based workshops [1]. The value of real-world, in-house simulation based training has also been shown to increase “practical preparedness” in the context of resuscitation training (4). However, there is relatively little data regarding the long term value of simulation based training in primary care (5). In the current paper, we assessed whether our workshops had any longer-term benefit on participants’ confidence in managing emergencies and if it led to any changes in clinical practice
DNA molecules and human therapeutics
Nucleic acid molecules are championing a new generation of reverse engineered biopharmaceuticals. In terms of potential application in gene medicine, plasmid DNA (pDNA) vectors have exceptional therapeutic and immunological profiles as they are free from safety concerns associated with viral vectors, display non-toxicity and are simpler to develop. This review addresses the potential applications of pDNA molecules in vaccine design/development and gene therapy via recombinant DNA technology as well as a staged delivery mechanism for the introduction of plasmid-borne gene to target cells via the nasal route
Ethical difficulties in clinical practice : experiences of European doctors
Background: Ethics support services are growing in Europe to help doctors in dealing with ethical difficulties.
Currently, insufficient attention has been focused on the experiences of doctors who have faced ethical
difficulties in these countries to provide an evidence base for the development of these services.
Methods: A survey instrument was adapted to explore the types of ethical dilemma faced by European
doctors, how they ranked the difficulty of these dilemmas, their satisfaction with the resolution of a recent
ethically difficult case and the types of help they would consider useful. The questionnaire was translated and
given to general internists in Norway, Switzerland, Italy and the UK.
Results: Survey respondents (n = 656, response rate 43%) ranged in age from 28 to 82 years, and averaged
25 years in practice. Only a minority (17.6%) reported having access to ethics consultation in individual
cases. The ethical difficulties most often reported as being encountered were uncertain or impaired decisionmaking
capacity (94.8%), disagreement among caregivers (81.2%) and limitation of treatment at the end of
life (79.3%). The frequency of most ethical difficulties varied among countries, as did the type of issue
considered most difficult. The types of help most often identified as potentially useful were professional
reassurance about the decision being correct (47.5%), someone capable of providing specific advice
(41.1%), help in weighing outcomes (36%) and clarification of the issues (35.9%). Few of the types of help
expected to be useful varied among countries.
Conclusion: Cultural differences may indeed influence how doctors perceive ethical difficulties. The type of
help needed, however, did not vary markedly. The general structure of ethics support services would not have
to be radically altered to suit cultural variations among the surveyed countries
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