Non-Perturbative One-Loop Effective Action for Electrodynamics in Curved Spacetime

In this paper we explicitly evaluate the one-loop effective action in four dimensions for scalar and spinor fields under the influence of a strong, covariantly constant, magnetic field in curved spacetime. In the framework of zeta function regularization, we find the one-loop effective action to all orders in the magnetic field up to linear terms in the Riemannian curvature. As a particular case, we also obtain the one-loop effective action for massless scalar and spinor fields. In this setting, we found that the vacuum energy of charged spinors with small mass becomes very large due entirely by the gravitational correction.Comment: LaTeX, 23 page

Integrated street design in high-volume junctions: The case study of London’s Oxford Circus

While traditional street design relied upon segregating vehicles and pedestrians in urban areas to ensure smooth traffic flow, urban planners and traffic engineers are gradually moving away from it. Instead, under the more modern concept of integrated street design, more space and freedom of action is provided to pedestrians, the needs of whom were previously omitted. An example space to have undergone redevelopment to a more pedestrian-oriented design is London’s Oxford Circus junction. Comparing with the results of a study pre-redevelopment, the present study aims at identifying the shift in the perceptions of the pedestrians when using the space post-implementation of the new design at Oxford Circus, but also at drawing generic conclusions on the perceptions of the pedestrians towards such schemes. A questionnaire is developed and data is collected through on-street interviews with pedestrians at Oxford Circus. The results show that integrated street design offers improved way-finding, better perceived safety and more pleasant environments for pedestrians

More efficient Bell inequalities for Werner states

In this paper we study the nonlocal properties of two-qubit Werner states parameterized by the visibility parameter 0<p<1. New family of Bell inequalities are constructed which prove the two-qubit Werner states to be nonlocal for the parameter range 0.7056<p<1. This is slightly wider than the range 0.7071<p<1, corresponding to the violation of the Clauser-Horne-Shimony-Holt (CHSH) inequality. This answers a question posed by Gisin in the positive, i.e., there exist Bell inequalities which are more efficient than the CHSH inequality in the sense that they are violated by a wider range of two-qubit Werner states.Comment: 7 pages, 1 figur

SUJEITO E LINGUAGEM NA SÍNDROME DO X-FRÁGIL: CAMINHANDO PELA NEUROLINGUÍSTICA DISCURSIVA NO CORPO A CORPO COM OS DISPOSITIVOS

Apresento uma reflexão sobre o discurso científico veiculado em diferentes publicações sobre a Síndrome do X-Frágil. Com base em algumas obras de Foucault, procuro analisar como essa patologia é descrita pela área médica, especialmente em relação ao processo de aquisição da linguagem, quais efeitos de poder/saber são produzidos por esse discurso e suas implicações. Tendo isso em vista, acompanho o processo de aquisição e uso da fala/leitura/escrita de três sujeitos portadores da síndrome, em sessões semanais em grupo (CCazinho/IEL/UNICAMP) e/ou individuais. A partir dos pressupostos teórico-metodológicos formulados pela Neurolinguística Discursiva (COUDRY e FREIRE, 2010), busco identificar as dificuldades linguísticas desses sujeitos de forma a apontar aquilo que pode ser patológico, o que faz parte do processo normal de aquisição e uso da fala/leitura/escrita e o que pode estar relacionado a outros fatores. Apresento algumas análises de forma a contrapor os dados observados com o discurso determinístico da área médica

'She's like a daughter to me': insights into care, work and kinship from rural Russia

This article draws on ethnographic research into a state-funded homecare service in rural Russia. The article discusses intersections between care, work and kinship in the relationships between homecare workers and their elderly wards and explores the ways in which references to kinship, as a means of authenticating paid care and explaining its emotional content, reinforce public and private oppositions while doing little to relieve the tensions and conflicts of care work. The discussion brings together detailed empirical insights into local ideologies and practices as a way of generating new theoretical perspectives, which will be of relevance beyond the particular context of study

Strangelets: Who is Looking, and How?

It has been over 30 years since the first suggestion that the true ground state of cold hadronic matter might be not nuclear matter but rather strange quark matter (SQM). Ever since, searches for stable SQM have been proceeding in various forms and have observed a handful of interesting events but have neither been able to find compelling evidence for stable strangelets nor to rule out their existence. I will survey the current status and near future of such searches with particular emphasis on the idea of SQM from strange star collisions as part of the cosmic ray flux.Comment: Talk given at International Conference on Strangeness in Quark Matter, 2006. 8 pages. 1 figur

Evaluation of a large-scale donation of Lifebox pulse oximeters to non-physician anaesthetists in Uganda

Summary Pulse oximetry is widely accepted as essential monitoring for safe anaesthesia, yet is frequently unavailable in resource-limited settings. The Lifebox pulse oximeter, and associated management training programme, was delivered to 79 non-physician anaesthetists attending the 2011 Uganda Society of Anaesthesia Annual Conference. Using a standardised assessment, recipients were tested for their knowledge of oximetry use and hypoxia management before, immediately following and 3–5 months after the training. Before the course, the median (IQR [range]) test score for the anaesthetists was 36 (34–39 [26–44]) out of a maximum of 50 points. Immediately following the course, the test score increased to 41 (38–43 [25–47]); p < 0.0001 and at the follow-up visit at 3–5 months it was 41 (39–44 [33–49]); p = 0.001 compared with immediate post-training test scores, and 75/79 (95%) oximeters were in routine clinical use. This method of introduction resulted in a high rate of uptake of oximeters into clinical practice and a demonstrable retention of knowledge in a resource-limited setting

Uniqueness of reconstruction and an inversion procedure for thermoacoustic and photoacoustic tomography

The paper contains a simple approach to reconstruction in Thermoacoustic and Photoacoustic Tomography. The technique works for any geometry of point detectors placement and for variable sound speed satisfying a non-trapping condition. A uniqueness of reconstruction result is also obtained

Prolonged gastroparesis after corrective surgery for Wilkie's syndrome: a case report

<p>Abstract</p> <p>Introduction</p> <p>Wilkie's syndrome, a rare cause of intestinal obstruction, is related to anatomical and mechanical factors associated with the reduction of retroperitoneal fat padding. The diagnostic challenges of identifying vascular constriction between the aorta and superior mesenteric artery have been answered by advances in the field of computed tomography. Despite diagnostic confusion with intestinal dysmotility syndrome, conservative therapy with nutritional supplementation is the initial approach and duodenojejunostomy is favoured if non-surgical treatment fails.</p> <p>Case presentation</p> <p>We present a case of a 49-year-old woman with Wilkie's syndrome with persistent symptoms of gastroparesis for 15 months following corrective surgery.</p> <p>Conclusion</p> <p>Open and laparoscopic duodenojejunostomy have been described as the best surgical treatment options for Wilkie's syndrome, but further work needs to be done for patients with refractory symptoms of gastroparesis after these corrective surgeries.</p