139 research outputs found
Torsion nonminimally coupled to the electromagnetic field and birefringence
In conventional Maxwell--Lorentz electrodynamics, the propagation of light is
influenced by the metric, not, however, by the possible presence of a torsion
T. Still the light can feel torsion if the latter is coupled nonminimally to
the electromagnetic field F by means of a supplementary Lagrangian of the type
l^2 T^2 F^2 (l = coupling constant). Recently Preuss suggested a specific
nonminimal term of this nature. We evaluate the spacetime relation of Preuss in
the background of a general O(3)-symmetric torsion field and prove by
specifying the optical metric of spacetime that this can yield birefringence in
vacuum. Moreover, we show that the nonminimally coupled homogeneous and
isotropic torsion field in a Friedmann cosmos affects the speed of light.Comment: Revtex, 12 pages, no figure
Развитие стресс-менеджмента в системе управления персоналом предприятия на примере ОАО "Томскнефть" ВНК
Стресс-менеджмент и его методика позволяют быстро и эффективно решить стрессовую ситуацию возникшую в организации. Развитие стресс-менеджмента в системе управления персоналом предприятия позволит сформировать конструктивное отношение к стрессовым ситуациям на рабочем месте. Большую часть своего времени современный человек проводит на работе. Высокая нагрузка на работе; недостаточное количество сна; конфликты на работе; отсутствие контроля; отсутствие эмоциональной поддержки со стороны сослуживцев приводят к выявлению у человека одного из синдромов: "boreout" или "burnout". В данной работе были сформированы методические указания конструктивного отношения к стрессовым ситуациям и методам саморегулирования.Stress management and its methodology allow to quickly and effectively solve the stressful situation that arose in the organization. The development of stress management in the personnel management system of the enterprise will allow to form a constructive attitude to stressful situations in the workplace. Most of his time a modern man spends at work. High work load; Insufficient sleep; Conflicts at work; Lack of control; The lack of emotional support from co-workers lead to the identification of a person in one of the syndromes: "boreout" or "burnout". In this work, methodical instructions for a constructive attitude to stressful situations and methods of self-regulation have been formed
Cranial and ventricular size following shunting or endoscopic third ventriculostomy (ETV) in infants with aqueductal stenosis: further insights from the International Infant Hydrocephalus Study (IIHS)
Purpose: The craniometrics of head circumference (HC) and ventricular size are part of the clinical assessment of infants with hydrocephalus and are often utilized in conjunction with other clinical and radiological parameters to determine the success of treatment. We aimed to assess the effect of endoscopic third ventriculostomy (ETV) and shunting on craniometric measurements during the follow-up of a cohort of infants with symptomatic triventricular hydrocephalus secondary to aqueductal stenosis. Methods: We performed a post hoc analysis of data from the International Infant Hydrocephalus Study (IIHS)—a prospective, multicenter study of infants (\u3c 24 months old) with hydrocephalus from aqueductal stenosis who were treated with either an ETV or shunt. During various stages of a 5-year follow-up period, the following craniometrics were measured: HC, HC centile, HC z-score, and frontal-occipital horn ratio (FOR). Data were compared in an analysis of covariance, adjusting for baseline variables including age at surgery and sex. Results: Of 158 enrolled patients, 115 underwent an ETV, while 43 received a shunt. Both procedures led to improvements in the mean HC centile position and z-score, a trend which continued until the 5-year assessment point. A similar trend was noted for FOR which was measured at 12 months and 3 years following initial treatment. Although the values were consistently higher for ETV compared with shunt, the differences in HC value, centile, and z-score were not significant. ETV was associated with a significantly higher FOR compared with shunting at 12 months (0.52 vs 0.44; p = 0.002) and 3 years (0.46 vs 0.38; p = 0.03) of follow-up. Conclusion: ETV and shunting led to improvements in HC centile, z-score, and FOR measurements during long-term follow-up of infants with hydrocephalus secondary to aqueductal stenosis. Head size did not significantly differ between the treatment groups during follow-up, however ventricle size was greater in those undergoing ETV when measured at 1 and 3 years following treatment
Head of State of Exception
During the escalation of the “German Autumn” in 1977 the Federal German government resorted to a specific form of crisis management that had been described as an undeclared state of exception. It was Federal chancellor Helmut Schmidt in the first place who oversaw the anti-terrorist measures in the situation room where the executive branch ruled for six weeks beyond any parliamentary control. This article examines the role that Helmut Schmidt had played for the creation of a “subjective state of exception” (Julius Hatschek) and how this could be seen as stemming from Schmidt’s earlier experiences and handling of crisis situations dating back to the 1960s. In this regard it has to be asked with Giorgio Agamben, if in the West German case, the state of exception had become the rule
Health-related qualify of life, angina type and coronary artery disease in patients with stable chest pain.
Health-related quality of life (HRQoL) is impaired in patients with stable angina but patients often present with other forms of chest pain. The aim of this study was to compare the pre-diagnostic HRQoL in patients with suspected coronary artery disease (CAD) according to angina type, gender, and presence of obstructive CAD. From the pilot study for the European DISCHARGE trial, we analysed data from 24 sites including 1263 patients (45.9% women, 61.1 ± 11.3 years) who were clinically referred for invasive coronary angiography (ICA; 617 patients) or coronary computed tomography angiography (CTA; 646 patients). Prior to the procedures, patients completed HRQoL questionnaires: the Short Form (SF)-12v2, the EuroQoL (EQ-5D-3 L) and the Hospital Anxiety and Depression Scale. Fifty-five percent of ICA and 35% of CTA patients had typical angina, 23 and 33% had atypical angina, 18 and 28% had non-anginal chest discomfort and 5 and 5% had other chest discomfort, respectively. Patients with typical angina had the poorest physical functioning compared to the other angina groups (SF-12 physical component score; 41.2 ± 8.8, 43.3 ± 9.1, 46.2 ± 9.0, 46.4 ± 11.4, respectively, all age and gender-adjusted p < 0.01), and highest anxiety levels (8.3 ± 4.1, 7.5 ± 4.1, 6.5 ± 4.0, 4.7 ± 4.5, respectively, all adjusted p < 0.01). On all other measures, patients with typical or atypical angina had lower HRQoL compared to the two other groups (all adjusted p < 0.05). HRQoL did not differ between patients with and without obstructive CAD while women had worse HRQoL compared with men, irrespective of age and angina type. Prior to a diagnostic procedure for stable chest pain, HRQoL is associated with chest pain characteristics, but not with obstructive CAD, and is significantly lower in women. Clinicaltrials.gov, NCT02400229
A spontaneous ad hoc network to share www access
In this paper, we propose a secure spontaneous ad-hoc network, based on direct peer-to-peer interaction, to grant a quick, easy, and secure access to the users to surf the Web. The paper shows the description of our proposal, the procedure of the nodes involved in the system, the security algorithms implemented, and the designed messages. We have taken into account the security and its performance. Although some people have defined and described the main features of spontaneous ad-hoc networks, nobody has published any design and simulation until today. Spontaneous networking will enable a more natural form of wireless computing when people physically meet in the real world. We also validate the success of our proposal through several simulations and comparisons with a regular architecture, taking into account the optimization of the resources of the devices. Finally, we compare our proposal with other caching techniques published in the related literature. The proposal has been developed with the main objective of improving the communication and integration between different study centers of low-resource communities. That is, it lets communicate spontaneous networks, which are working collaboratively and which have been created on different physical places.Authors want to give thanks to the anonymous reviewers for their valuable suggestions, useful comments, and proofreading of this paper. This work was partially supported by the Ministerio de Educacion y Ciencia, Spain, under Grant no. TIN2008-06441-C02-01, and by the "Ayudas complementarias para proyectos de I+D para grupos de calidad de la Generalitat Valenciana" (ACOMP/2010/005).Lacuesta Gilaberte, R.; Lloret, J.; García Pineda, M.; Peñalver Herrero, ML. (2010). A spontaneous ad hoc network to share www access. 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Health-related qualify of life, angina type and coronary artery disease in patients with stable chest pain
Background Health-related quality of life (HRQoL) is impaired in patients with stable angina but patients often present with other forms of chest pain. The aim of this study was to compare the pre-diagnostic HRQoL in patients with suspected coronary artery disease (CAD) according to angina type, gender, and presence of obstructive CAD. Methods From the pilot study for the European DISCHARGE trial, we analysed data from 24 sites including 1263 patients (45.9% women, 61.1 +/- 11.3 years) who were clinically referred for invasive coronary angiography (ICA; 617 patients) or coronary computed tomography angiography (CTA; 646 patients). Prior to the procedures, patients completed HRQoL questionnaires: the Short Form (SF)-12v2, the EuroQoL (EQ-5D-3 L) and the Hospital Anxiety and Depression Scale. Results Fifty-five percent of ICA and 35% of CTA patients had typical angina, 23 and 33% had atypical angina, 18 and 28% had non-anginal chest discomfort and 5 and 5% had other chest discomfort, respectively. Patients with typical angina had the poorest physical functioning compared to the other angina groups (SF-12 physical component score; 41.2 +/- 8.8, 43.3 +/- 9.1, 46.2 +/- 9.0, 46.4 +/- 11.4, respectively, all age and gender-adjusted p < 0.01), and highest anxiety levels (8.3 +/- 4.1, 7.5 +/- 4.1, 6.5 +/- 4.0, 4.7 +/- 4.5, respectively, all adjusted p < 0.01). On all other measures, patients with typical or atypical angina had lower HRQoL compared to the two other groups (all adjusted p < 0.05). HRQoL did not differ between patients with and without obstructive CAD while women had worse HRQoL compared with men, irrespective of age and angina type. Conclusions Prior to a diagnostic procedure for stable chest pain, HRQoL is associated with chest pain characteristics, but not with obstructive CAD, and is significantly lower in women
From notebooks to Data-Pipelines : The Darmstadt Approach to handling measurement data and metadata.
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