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Full Analysis (full + analysis)
Selected AbstractsHow good are the Electrodes we use in PEFC?FUEL CELLS, Issue 3 2004M. Eikerling Abstract Basically, companies and laboratories implement production methods for their electrodes on the basis of experience, technical capabilities and commercial preferences. But how does one know whether they have ended up with the best possible electrode for the components used? What should be the (i) optimal thickness of the catalyst layer? (ii) relative amounts of electronically conducting component (catalyst, with support , if used), electrolyte and pores? (iii) "particle size distributions" in these mesophases? We may be pleased with our MEAs, but could we make them better? The details of excellently working MEA structures are typically not a subject of open discussion, also hardly anyone in the fuel cell business would like to admit that their electrodes could have been made much better. Therefore, we only rarely find (far from systematic) experimental reports on this most important issue. The message of this paper is to illustrate how strongly the MEA morphology could affect the performance and to pave the way for the development of the theory. Full analysis should address the performance at different current densities, which is possible and is partially shown in this paper, but vital trends can be demonstrated on the linear polarization resistance, the signature of electrode performance. The latter is expressed through the minimum number of key parameters characterizing the processes taking place in the MEA. Model expressions of the percolation theory can then be used to approximate the dependence on these parameters. The effects revealed are dramatic. Of course, the corresponding curves will not be reproduced literally in experiments, since these illustrations use crude expressions inspired by the theory of percolation on a regular lattice, whereas the actual mesoscopic architecture of MEA is much more complicated. However, they give us a flavour of reserves that might be released by smart MEA design. [source] Triadic bed-sharing and infant temperatureCHILD: CARE, HEALTH AND DEVELOPMENT, Issue 2002H. L. Ball Abstract The effects on infants of sleeping with their parents is currently the subject of much debate. One concern regarding infants who sleep in their parents' bed involves the possibility of overheating. Previous research reported a significantly greater core temperature of 0.1°C among a cohort of bed-sharing infants compared with a matched cohort of infants sleeping alone. This paper presents a preliminary analysis of the overnight rectal temperature of 12 of the 20 infants who were monitored sleeping alone and with their parents on separate nights at the University of Durham Parent-Infant Sleep Lab. No significant differences were found in all night rectal temperature, or temperature from 2 h after sleep onset between bed-sharing and cot sleeping nights. These preliminary analyses suggest a night-time difference in rectal temperature between routine bed-sharers and routine cot sleepers, however, these findings will be further explored in the full analyses for this study. [source] An Eye Gaze Model for Dyadic Interaction in an Immersive Virtual Environment: Practice and ExperienceCOMPUTER GRAPHICS FORUM, Issue 1 2004V. Vinayagamoorthy Abstract This paper describes a behavioural model used to simulate realistic eye-gaze behaviour and body animations for avatars representing participants in a shared immersive virtual environment (IVE). The model was used in a study designed to explore the impact of avatar realism on the perceived quality of communication within a negotiation scenario. Our eye-gaze model was based on data and studies carried out on the behaviour of eye-gaze during face-to-face communication. The technical features of the model are reported here. Information about the motivation behind the study, experimental procedures and a full analysis of the results obtained are given in [17]. [source] From Work as Sex to Sex as Work: Networks, ,Others' and Occupations in the Analysis of WorkGENDER, WORK & ORGANISATION, Issue 5 2002Jackie West While once upon a time the social science of work and organization neglected or marginalized gender and sexuality, we have now lost sight of what people actually do, that is to say the activity of work. Gender and sexuality have been identified as crucial to organizational dynamics and, notwithstanding different theoretical emphases, this paradigm has become increasingly influential. We argue (contrary to most of its protagonists) that , within this model , the significance of sex and gender for organization rests principally on their role in the production of identities rather than in what they can tell us about production or work in any wider sense. The article highlights parallels with the ways in which prostitution is now generally understood, whether the emphasis is on subordination or agency. This literature also emphasizes gender relations and identities, even where the focus is on re,writing ,sex as work'. We argue that this focus neglects the wider networks in which all work, whether mainstream or otherwise, is embedded and that a full analysis must take due account of both these networks and the discursive production of identities. Examples , of work in the finance and sex industries , are used to substantiate this argument and a case is made for the importance of the Chicago School's analysis of occupations. [source] Clinical trial: the safety and short-term efficacy of recombinant cholera toxin B subunit in the treatment of active Crohn's diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 3 2010P. STÅL Aliment Pharmacol Ther,31, 387,395 Summary Background, The cholera toxin B subunit ameliorates experimentally induced colitis in mice. In humans, cholera toxin B subunit has never been tested in the treatment of Crohn's disease (CD). Aim, To evaluate the safety and efficacy of treatment with recombinant cholera toxin B subunit of patients with CD. Methods, An open-label, multicentre, nonrandomized trial including 15 patients with mild/moderate CD. Patients received an oral solution of 5 mg recombinant cholera toxin B subunit three times weekly for 2 weeks. Reduction in CD Activity Index (CDAI) with >100 between baseline and days 15, 29, 42 and 70 defined clinical response. Patients with CDAI score ,150 were defined as being in remission. Results, A significant decrease in CDAI score was observed. Response rates were 40% in the full analysis set and 42% in the per protocol analysis. Two patients receiving adjuvant treatment after day 29 were excluded, after which 40% were in remission at 4 weeks and 30% at 8 weeks post-treatment. Mild side effects (arthralgia, headache and pruritus) were seen in 33% of patients. Conclusions, Treatment with recombinant cholera toxin B subunit was safe. Approximately 40% of patients with active CD responded to treatment. Randomized studies are needed to establish the clinical efficacy of recombinant cholera toxin B subunit. [source] Multivariate Composition Distribution in Free-Radical Multicomponent Polymerization, 1MACROMOLECULAR THEORY AND SIMULATIONS, Issue 7 2003Hidetaka Tobita Abstract Statistical multicomponent polymerization is a typical example of a Markovian process for which the generating function approach can be applied. Up to the present, generating functions have been used mainly to obtain analytical solutions. However, recent advances of computer software capable of handling symbolic calculations can throw new light on the old mathematical technique. After formulating the equations representing the instantaneous composition distribution of polymers for a given chain length, r, the illustrative numerical calculations are conducted by using the symbolic calculator. For a multicomponent polymerization consisting of more than two components, the second component distribution is dependent on the composition of the first component (F1), which is represented by the conditional probability given r and F1, . It is found that is well approximated by the Gaussian distribution with the variance following the relationship, , as in the case of the first component distribution , where A and B are the constants. With the knowledge of chain length distribution, it is now possible to conduct the full analysis of multivariate distribution of chain length and compositions for multicomponent free-radical polymerization. Bivariate distribution of composition F1 and F2 for chain length r,=,100 in a three-component system. [source] Health care assistants' role, function and development: results of a national surveyNURSING IN CRITICAL CARE, Issue 4 2003The British Association of Critical Care NursesArticle first published online: 31 JUL 200 Summary ,,Intensive care has developed as a speciality since the 1950s; during this time there have been major technological advances in health care provision leading to a rapid expansion of all areas of critical care ,,The ongoing problem of recruiting appropriately qualified nurses has affected staffing levels in many units and continues to be a national problem. For many, the answer lies in employing health care assistants to support the work of registered nurses ,,A key aim of the British Association of Critical Care Nurses is to promote the art and science of critical care nursing by providing representation for its members, by responding to political and professional change and by producing and publishing position statements ,,A primary component of the work surrounding the development of this second position statement was the gathering of contemporary information in relation to the role of health care assistants within critical care units throughout the UK, through a survey of 645 critical care units within the UK ,,At present the impact upon the role of the critical care nurse is not fully understood, with research in this area suggesting that although there is a role for the health care assistant in the critical care environment, this should only be undertaken with a full analysis of this impact upon the work of the registered nurse [source] A Cournot,Nash Model of Family Decision MakingTHE ECONOMIC JOURNAL, Issue 474 2001Zhiqi Chen This paper models a two-person family. Each family member is utility maximising, yet family members are interdependent because of caring and public goods within the family. The two family members' interdependent utility maximisation problems are first solved using a non-cooperative, or Cournot,Nash, game theoretic framework. The Cournot,Nash equilibrium is then used as a threat point in a bargaining game. The paper provides a rigorous derivation of the properties of household demands, a full analysis of the determinants of intra-household resource allocation, including the effect of varying household bargaining power, and consideration of policy implications. [source] The analysis of the homoerotic and the pursuit of meaningTHE JOURNAL OF ANALYTICAL PSYCHOLOGY, Issue 3 2006Barry Miller Abstract:, This paper explores the dynamic tension between an evolving collective phenomenon and the nature of analytic process. Specifically, the focus will be erotic experiences which acquire a meaning through the culture at large, a meaning that may not be supportable when that material is subjected to psychological analysis. This stimulates a conflict between the symbolic attitude and the cultural perspective of the time. While the struggle between the individual and collective consciousness always emerges in analysis, the subject of same-gender sexual relations has become such a controversial and divisive issue in the current political environment that views toward homosexuality demand powerful allegiances and identification with either historic or contemporary ideas. People now identify as ,gay' and tend to see themselves as something akin to a race or perhaps alternative gender. Sexuality and relationship between same gendered people tends to be viewed through the lens of civil rights and the undeniable need for social equality. In this far-reaching and expanding collective phenomenon, psychology, in its support of human rights and accommodation to emerging trends, may be diminished in its capacity to pursue the meaning inherent in these human experiences. The position developed in this paper is that psychological experience, whether in the imaginal realm, dreams or personal consciousness, must be available for full analysis. Clinical experience and dreams are used to amplify this challenge to dynamic analytic practice. [source] Cyclic Carbonate Synthesis Catalysed by Bimetallic Aluminium,Salen ComplexesCHEMISTRY - A EUROPEAN JOURNAL, Issue 23 2010William Clegg Prof. Abstract The development of bimetallic aluminium,salen complexes [{Al(salen)}2O] as catalysts for the synthesis of cyclic carbonates (including the commercially important ethylene and propylene carbonates) from a wide range of terminal epoxides in the presence of tetrabutylammonium bromide as a cocatalyst is reported. The bimetallic structure of one complex was confirmed by X-ray crystallography. The bimetallic complexes displayed exceptionally high catalytic activity and in the presence of tetrabutylammonium bromide could catalyse cyclic carbonate synthesis at atmospheric pressure and room temperature. Catalyst-reuse experiments demonstrated that one bimetallic complex was stable for over 60 reactions, though the tetrabutylammonium bromide decomposed in situ by a retro-Menschutkin reaction to form tributylamine and had to be regularly replaced. The mild reaction conditions allowed a full analysis of the reaction kinetics to be carried out and this showed that the reaction was first order in aluminium complex concentration, first order in epoxide concentration, first order in carbon dioxide concentration (except when used in excess) and unexpectedly second order in tetrabutylammonium bromide concentration. Further kinetic experiments demonstrated that the tributylamine formed in situ was involved in the catalysis and that addition of butyl bromide to reconvert the tributylamine into tetrabutylammonium bromide resulted in inhibition of the reaction. The reaction kinetics also indicated that no kinetic resolution of racemic epoxides was possible with this class of catalysts, even when the catalyst was derived from a chiral salen ligand. However, it was shown that if enantiomerically pure styrene oxide was used as substrate, then enantiomerically pure styrene carbonate was formed. On the basis of the kinetic and other experimental data, a catalytic cycle that explains why the bimetallic complexes display such high catalytic activity has been developed. [source] | ||||||||||||||||