5,764 research outputs found
Means for growing ribbon crystals without subjecting the crystals to thermal shock-induced strains
A susceptor particularly suited for use in growing a ribbon crystal employing edge defined film fed growth techniques is described. The susceptor includes a die through which a melt is drawn for forming a crystal ribbon. This is combined with a coolant delivery system characterized by a pair of jets for directing a stream of fluid coolant along a path extended to impinge on the susceptor in close proximity with the die in nonincident relation with the crystal being grown
Galaxy-cluster gas-density distributions of the Representative XMM-Newton Cluster Structure Survey (REXCESS)
Original article can be found at: http://www.aanda.org/ Copyright The European Southern Observatory (ESO).Peer reviewe
Women’s Contributions to the Progress of Mathematics: Lights and Shadows
We deal with many of the notable women whose mathematical accomplishments
are best appreciated through an understanding of the societies and the problems that shaped their lives. Women have participated in many of the greatest and most enduring intellectual achievements in mathematics and have enjoyed its powerful satisfactions and its aesthetics values. Not only were their intellectual investments remarkable as those of male mathematicians, but they needed an extra dimension of stamina and fortitude to cope with the prejudice against women working in hard sciences. We enjoy talking about them , because none of their lives were dull and indeed some of them were so unusual they have been romanticized. Their rich personalities and their remarkable personal lives deserve to capture our attention
Perturbed Spherically Symmetric Dust Solution of the Field Equations in Observational Coordinates with Cosmological Data Functions
Using the framework for solving the spherically symmetric field equations in
observational coordinates given in Araujo and Stoeger (1999), their formulation
and solution in the perturbed FLRW sperically symmetric case with observational
data representing galaxy redshifts, number counts and observer area distances,
both as functions of redshift on our past light cone, are presented. The
importance of the central conditions, those which must hold on our world line
C, is emphasized. In detailing the solution for these perturbations, we discuss
the gauge problem and its resolution in this context, as well as how errors and
gaps in the data are propagated together with the genuine perturbations. This
will provide guidance for solving, and interpreting the solutions of the more
complicated general perturbation problem with observational data on our past
light cone.Comment: Latex 23 pages, no figures, submitted to Astrophysical Journa
Perturbation expansions for a class of singular potentials
Harrell's modified perturbation theory [Ann. Phys. 105, 379-406 (1977)] is
applied and extended to obtain non-power perturbation expansions for a class of
singular Hamiltonians H = -D^2 + x^2 + A/x^2 + lambda/x^alpha, (A\geq 0, alpha
> 2), known as generalized spiked harmonic oscillators. The perturbation
expansions developed here are valid for small values of the coupling lambda >
0, and they extend the results which Harrell obtained for the spiked harmonic
oscillator A = 0. Formulas for the the excited-states are also developed.Comment: 23 page
Telling partners about chlamydia: how acceptable are the new technologies?
BACKGROUND Partner notification is accepted as a vital component in the control of chlamydia. However, in reality, many sexual partners of individuals diagnosed with chlamydia are never informed of their risk. The newer technologies of email and SMS have been used as a means of improving partner notification rates. This study explored the use and acceptability of different partner notification methods to help inform the development of strategies and resources to increase the number of partners notified. METHODS Semi-structured telephone interviews were conducted with 40 people who were recently diagnosed with chlamydia from three sexual health centres and two general practices across three Australian jurisdictions. RESULTS Most participants chose to contact their partners either in person (56%) or by phone (44%). Only 17% chose email or SMS. Participants viewed face-to-face as the "gold standard" in partner notification because it demonstrated caring, respect and courage. Telephone contact, while considered insensitive by some, was often valued because it was quick, convenient and less confronting. Email was often seen as less personal while SMS was generally considered the least acceptable method for telling partners. There was also concern that emails and SMS could be misunderstood, not taken seriously or shown to others. Despite these, email and SMS were seen to be appropriate and useful in some circumstances. Letters, both from the patients or from their doctor, were viewed more favourably but were seldom used. CONCLUSION These findings suggest that many people diagnosed with chlamydia are reluctant to use the new technologies for partner notification, except in specific circumstances, and our efforts in developing partner notification resources may best be focused on giving patients the skills and confidence for personal interaction.The study was funded by the Australian Federal Government Department of Health and Ageing Chlamydia Pilot Program of Targeted Grants
International Public Health Research Involving Interpreters: a Case Study from Bangladesh
Background: Cross-cultural and international research are important components of public health research, but the challenges of language barriers and working with interpreters are often overlooked, particularly in the case of qualitative research.
Methods: A case-study approach was used to explore experiences of working with an interpreter in Bangladesh as part of a research project investigating women's experiences of emergency obstetric care.
The case study: Data from the researcher's field notes provided evidence of experiences in working with an interpreter and show how the model of interviewing was adapted over time to give a more active role to the interpreter. The advantages of a more active role were increased rapport and "flow" in interviews. The disadvantages included reduced control from the researcher's perspective. Some tensions between the researcher and interpreter remained hard to overcome,
irrespective of the model used. Independent transcription and translation of the interviews also raised questions around accuracy in translation.
Conclusion: The issues examined in this case study have broader implications for public health research. Further work is needed in three areas: 1) developing effective relationships with interpreters; 2) the impact of the interpreter on the research process; and 3) the accuracy of the translation and level of analysis needed in any specific public health research. Finally, this paper highlights the importance to authors of reflecting on the potential impact of translation and interpretation on the research process when disseminating their research
Imaging characteristics and treatment of a penetrating brain injury caused by an oropharyngeal foreign body in a dog
A 4-year-old Border collie was presented with one episode of collapse, altered mentation, and a suspected pharyngeal stick injury. Magnetic resonance imaging (MRI) and computed tomography showed a linear foreign body penetrating the right oropharynx, through the foramen ovale and the brain parenchyma. The foreign body was surgically removed and medical treatment initiated. Complete resolution of clinical signs was noted at recheck 8 weeks later. Repeat MRI showed chronic secondary changes in the brain parenchyma. To the authors' knowledge, this is the first report of the advanced imaging findings and successful treatment of a penetrating oropharyngeal intracranial foreign body in a dog
Better than nothing? Patient-delivered partner therapy and partner notification for chlamydia: the views of Australian general practitioners
BACKGROUND Genital chlamydia is the most commonly notified sexually transmissible infection (STI) in Australia and worldwide and can have serious reproductive health outcomes. Partner notification, testing and treatment are important facets of chlamydia control. Traditional methods of partner notification are not reaching enough partners to effectively control transmission of chlamydia. Patient-delivered partner therapy (PDPT) has been shown to improve the treatment of sexual partners. In Australia, General Practitioners (GPs) are responsible for the bulk of chlamydia testing, diagnosis, treatment and follow up. This study aimed to determine the views and practices of Australian general practitioners (GPs) in relation to partner notification and PDPT for chlamydia and explored GPs' perceptions of their patients' barriers to notifying partners of a chlamydia diagnosis. METHODS In-depth, semi-structured telephone interviews were conducted with 40 general practitioners (GPs) from rural, regional and urban Australia from November 2006 to March 2007. Topics covered: GPs' current practice and views about partner notification, perceived barriers and useful supports, previous use of and views regarding PDPT.Transcripts were imported into NVivo7 and subjected to thematic analysis. Data saturation was reached after 32 interviews had been completed. RESULTS Perceived barriers to patients telling partners (patient referral) included: stigma; age and cultural background; casual or long-term relationship, ongoing relationship or not. Barriers to GPs undertaking partner notification (provider referral) included: lack of time and staff; lack of contact details; uncertainty about the legality of contacting partners and whether this constitutes breach of patient confidentiality; and feeling both personally uncomfortable and inadequately trained to contact someone who is not their patient. GPs were divided on the use of PDPT--many felt concerned that it is not best clinical practice but many also felt that it is better than nothing.GPs identified the following factors which they considered would facilitate partner notification: clear clinical guidelines; a legal framework around partner notification; a formal chlamydia screening program; financial incentives; education and practical support for health professionals, and raising awareness of chlamydia in the community, in particular amongst young people. CONCLUSIONS GPs reported some partners do not seek medical treatment even after they are notified of being a sexual contact of a patient with chlamydia. More routine use of PDPT may help address this issue however GPs in this study had negative attitudes to the use of PDPT. Appropriate guidelines and legislation may make the use of PDPT more acceptable to Australian GPs.The Australian Federal Government Department of Health and Ageing Chlamydia Pilot Program of Targeted Grants funded the study
Effects of Backflow Correlation in the Three-Dimensional Electron Gas: Quantum Monte Carlo Study
The correlation energy of the homogeneous three-dimensional interacting
electron gas is calculated using the variational and fixed-node diffusion Monte
Carlo methods, with trial functions that include backflow and three-body
correlations. In the high density regime the effects of backflow dominate over
those due to three-body correlations, but the relative importance of the latter
increases as the density decreases. Since the backflow correlations vary the
nodes of the trial function, this leads to improved energies in the fixed-node
diffusion Monte Carlo calculations. The effects are comparable to those found
for the two-dimensional electron gas, leading to much improved variational
energies and fixed-node diffusion energies equal to the release-node energies
of Ceperley and Alder within statistical and systematic errors.Comment: 14 pages, 5 figures, submitted to Physical Review
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