278 research outputs found
The Suprafroth (Superconducting Froth)
The structure and dynamics of froths have been subjects of intense interest
due to the desire to understand the behaviour of complex systems where
topological intricacy prohibits exact evaluation of the ground state. The
dynamics of a traditional froth involves drainage and drying in the cell
boundaries, thus it is irreversible. We report a new member to the froths
family: suprafroth, in which the cell boundaries are superconducting and the
cell interior is normal phase. Despite very different microscopic origin,
topological analysis of the structure of the suprafroth shows that statistical
von Neumann and Lewis laws apply. Furthermore, for the first time in the
analysis of froths there is a global measurable property, the magnetic moment,
which can be directly related to the suprafroth structure. We propose that this
suprafroth is a new, model system for the analysis of the complex physics of
two-dimensional froths
An analysis of photoemission and inverse photoemission spectra of Si(111) and sulphur-passivated InP(001) surfaces
Photoemission (PES) and inverse-photoemission spectra (IPES) for the
sulphur-passivated InP(001) surface are compared with theoretical predictions
based on density-functional calculations. As a test case for our methods, we
also present a corresponding study of the better known Si(111) surface. The
reported spectra for InP(001)-S agree well with the calculated ones if the
surface is assumed to consist of a mixture of two phases, namely, the fully
S-covered -reconstructed structure, which contains four S atoms in
the surface unit-cell, and a structure containing two S and two P
atoms per unit cell. The latter has recently been identified in total-energy
calculations as well as in core-level spectra of S-passivated
Si(111)- is in excellent agreement with the calculations. The
comparison of the experimental-PES with our calculations provides additional
considerations regarding the nature of the sample surface. It is also found
that the commonly-used density-of-states approximation to the photo- and
inverse- photoemission spectra is not valid for these systems.Comment: Submitted to Phys. Rev. B; 6 postscript formatted pages; 7 figures in
gif format; postscript figures available upon reques
Notes on a scandal: the official enquiry into deviance and corruption in New Zealand police
Since 2004, the New Zealand Police Service has been engulfed by a series of scandals relating to allegations that officers have committed rape and sexual assault and conducted inappropriate sexual relations with vulnerable people. Moreover, it has been claimed that other officers engaged in corrupt practices to thwart the investigation and prosecution of criminal behaviour of police officers. In 2007, a Commission of Inquiry report established a program of reform intended to shape the future direction of the police service. This article provides an overview of these scandals, the context in which they have emerged, and the political and policing response to them. The analysis contained in the Commission report is compared with that offered by comparable investigations of police deviance and corruption in other countries. The methodological and conceptual limitations of the Commission are outlined and the prospects of the recommendations are considered
Negotiating professional and social voices in research principles and practice
This paper draws on work conducted for a qualitative interview based study which explores the gendered racialised and professional identifications of health and social care professionals. Participants for the project were drawn from the professional executive committees of recently formed Primary Care Trusts. The paper discusses how the feminist psychosocial methodological approach developed for the project is theoretically, practically and ethically useful in exploring the voices of those in positions of relative power in relation to both health and social care services and the social relations of gender and ethnicity. The approach draws on psychodynamic accounts of (defended) subjectivity and the feminist work of Carol Gilligan on a voice-centred relational methodology. Coupling the feminist with the psychosocial facilitates an emphasis on voice and dialogic communication between participant and researcher not always captured in psychosocial approaches which tend towards favouring the interviewer as âgood listenerâ. This emphasis on dialogue is important in research contexts where prior and ongoing relationships with professional participants make it difficult and indeed undesirable for researchers to maintain silence
Engaging with History after Macpherson
The Race Relations Amendment Act (2000) identifies a key role for education, and more specifically history, in promoting ârace equalityâ in Britain. In this article Ian Grosvenor and Kevin Myers consider the extent of young peopleâs current engagement with the history of âdiversity, change and immigrationâ which underpins the commitment to ârace equalityâ. Finding that in many of Britainâs schools and universities a singular and exclusionary version of history continues to dominate the curriculum, they go on to consider the reasons for the neglect of multiculturalism. The authors identify the development of an aggressive national identity that depends on the past for its legitimacy and argue that this sense of the past is an important obstacle to future progress
Deepening democracy within Ireland's social partnership
Ireland's social partnership process, now under attack from a number of quarters, has repeatedly been charged with being 'undemocratic' in that it undermines the sovereign position of elected political representatives, with key policy formulation and decision-making taking place in fora outside the institutions of representative democracy. These critiques echo those against new forms of networked governance more globally. A key question therefore is how (and if) democracy may be deepened within social partnership or its potential successor(s). This article addresses this question by employing a post-liberal democratic framework to examine social partnership in practice, and by drawing lessons from another partnership process, Malawi's PRSP. Drawing from Malawi's experience, it is argued that democracy can be deepened within social partnership when governance deliberations and negotiations are conducted under conditions of vibrant public debate and genuine perspective-based representation, and when the communicative and discursive norms are widened to allow for such representation
Knowledge of Oral Cancer and Screening Practices of Primary Care Providers at Federally Qualified Health Centers
Objectives: Primary care providers (PCPs) who worked in Federally-Qualified Health Centers (FQHC) in Michigan were surveyed to assess their knowledge level and practices related to screening and preventing oral cancer. Methods: A questionnaire was developed with the assistance of dental and medical experts, and revised through focus groups. The questionnaire included one case scenario describing a suspicious oral lesion in a 55-year old female patient, followed by questions assessing PCPs' knowledge level, attitude, opinion, and screening practices for oral cancer. This mail survey was conducted in 2003. Results: Survey response rate was 56.4%. Over 70% of the respondents reported that they screen patients for oral cancer during a routine physical examination. Forty-four percent of PCPs had high knowledge level, based on the scenario questions. Those who had high knowledge level were more likely to be physicians, males, and more likely to perform screening for oral cancer than those with low knowledge level. There was no difference in age and race/ethnicity between high and low knowledge groups. Perceived barriers included (1) lack of education; (2) lack of specialists to refer patients; and (3) lack of reimbursement. Conclusions: The majority of PCPs in this survey had positive attitudes about performing screening for oral cancer. To involve PCPs in screening for oral cancer, oral health programs should focus on providing up-to-date education, setting up a referral system, and providing proper reimbursement.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65814/1/j.1752-7325.2005.tb02806.x.pd
The effect of the regular solution model in the condensation of protoplanetary dust
We utilize a chemical equilibrium code in order to study the condensation
process which occurs in protoplanetary discs during the formation of the first
solids. The model specifically focuses on the thermodynamic behaviour on the
solid species assuming the regular solution model. For each solution, we
establish the relationship between the activity of the species, the composition
and the temperature using experimental data from the literature. We then apply
the Gibbs free energy minimization method and study the resulting condensation
sequence for a range of temperatures and pressures within a protoplanetary
disc. Our results using the regular solution model show that grains condense
over a large temperature range and therefore throughout a large portion of the
disc. In the high temperature region (T > 1400 K) Ca-Al compounds dominate and
the formation of corundum is sensitive to the pressure. The mid-temperature
region is dominated by Fe(s) and silicates such as Mg2SiO4 and MgSiO3 . The
chemistry of forsterite and enstatite are strictly related, and our simulations
show a sequence of forsterite-enstatite-forsterite with decreasing temperature.
In the low temperature regions (T < 600 K) a range of iron compounds and
sulfides form. We also run simulations using the ideal solution model and see
clear differences in the resulting condensation sequences with changing
solution model In particular, we find that the turning point in which
forsterite replaces enstatite in the low temperature region is sensitive to the
solution model. Our results show that the ideal solution model is often a poor
approximation to experimental data at most temperatures important in
protoplanetary discs. We find some important differences in the resulting
condensation sequences when using the regular solution model, and suggest that
this model should provide a more realistic condensation sequence.Comment: MNRAS: Accepted 2011 February 16. Received 2011 February 14; in
original form 2010 July 2
Different responses of the blockade of the P2Y1 receptor with BPTU in human and porcine intestinal tissues and in cell cultures
Background: Gastrointestinal smooth muscle relaxation is accomplished by activation of P2Y 1 receptors, therefore this receptor plays an important role in regulation of gut motility. Recently, BPTU was developed as a negative allosteric modulator of the P2Y 1 receptor. Accordingly, the aim of this study was to assess the effect of BPTU on purinergic neurotransmission in pig and human gastrointestinal tissues. Methods: Ca 2+ imaging in tSA201 cells that express the human P2Y 1 receptor, organ bath and microelectrodes in tissues were used to evaluate the effects of BPTU on purinergic responses. Key results: BPTU concentration dependently (0.1 and 1 ”mol L â1) inhibited the rise in intracellular Ca 2+ evoked by ADP in tSA201 cells. In the pig small intestine, 30 ”mol L â1 BPTU reduced the fast inhibitory junction potential by 80%. Smooth muscle relaxations induced by electrical field stimulation were reduced both in pig ileum (EC 50 = 6 ”mol L â1) and colon (EC 50 = 35 ”mol L â1), but high concentrations of BPTU (up to 100 ”mol L â1) had no effect on human colonic muscle. MRS2500 (1 ”mol L â1) abolished all responses. Finally, 10 ”mol L â1 ADPÎČS inhibited spontaneous motility and this was partially reversed by 30 ”mol L â1 BPTU in pig, but not human colonic tissue and abolished by MRS2500 (1 ”mol L â1). Conclusions & inferences: BPTU blocks purinergic responses elicited via P2Y 1 receptors in cell cultures and in pig gastrointestinal tissue. However, the concentrations needed are higher in pig tissue compared to cell cultures and BPTU was ineffective in human colonic tissue
Law, necropolitics and the stop and search of young people
Stop and search can harm young people, damage relations between police and the community and alienate ethnic and racial minorities. In Mohidin and another v Commissioner of the Police of the Metropolis and others, a group of minors who had been stopped, searched and, in some cases, falsely imprisoned, assaulted and racially abused by officers, were awarded damages for the distress and pain suffered. In this article, the case will be read not for the tortious legal consequences of police actions towards youth, or members of the public in general, nor for the culpability of any of the parties concerned, but for how the use of âlawfulâ police powers on young people was framed and justified by both officers and the courts. It is argued that the punitive function of such powers has been underexplored by criminologists, and that the authorization and legitimization of such tactics, routinely defended as a ânecessaryâ crime prevention tool, can be understood as an instantiation of ânecropoliticsâ
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