494 research outputs found
Higgsing M2 to D2 with gravity: N=6 chiral supergravity from topologically gauged ABJM theory
We present the higgsing of three-dimensional N=6 superconformal ABJM type
theories coupled to conformal supergravity, so called topologically gauged ABJM
theory, thus providing a gravitational extension of previous work on the
relation between N M2 and N D2-branes. The resulting N=6 supergravity theory
appears at a chiral point similar to that of three-dimensional chiral gravity
introduced recently by Li, Song and Strominger, but with the opposite sign for
the Ricci scalar term in the lagrangian. We identify the supersymmetry in the
broken phase as a particular linear combination of the supersymmetry and
special conformal supersymmetry in the original topologically gauged ABJM
theory. We also discuss the higgsing procedure in detail paying special
attention to the role played by the U(1) factors in the original ABJM model and
the U(1) introduced in the topological gauging.Comment: 53 pages, Late
Multi-scalar tachyon potential on non-BPS domain walls
We have considered the multi-scalar and multi-tachyon fields living on a 3d
domain wall embedded in a 5d dimensional Minkowski spacetime. The effective
action for such a domain wall can be found by integrating out the normal modes
as vibrating modes around the domain wall solution of a truncated 5d
supergravity action. The multi-scalar tachyon potential are good enough to
modeling assisted inflation scenario with multi-tachyon fields. The tachyon
condensation are also briefly addressed.Comment: version to appear in JHEP, 18 pages, 3 figure
Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016.
OBJECTIVE: To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012." DESIGN: A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development. METHODS: The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable. RESULTS: The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions. CONCLUSIONS: Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality
Change in brain activity through virtual reality-based brain-machine communication in a chronic tetraplegic subject with muscular dystrophy
<p>Abstract</p> <p>Background</p> <p>For severely paralyzed people, a brain-computer interface (BCI) provides a way of re-establishing communication. Although subjects with muscular dystrophy (MD) appear to be potential BCI users, the actual long-term effects of BCI use on brain activities in MD subjects have yet to be clarified. To investigate these effects, we followed BCI use by a chronic tetraplegic subject with MD over 5 months. The topographic changes in an electroencephalogram (EEG) after long-term use of the virtual reality (VR)-based BCI were also assessed. Our originally developed BCI system was used to classify an EEG recorded over the sensorimotor cortex in real time and estimate the user's motor intention (MI) in 3 different limb movements: feet, left hand, and right hand. An avatar in the internet-based VR was controlled in accordance with the results of the EEG classification by the BCI. The subject was trained to control his avatar via the BCI by strolling in the VR for 1 hour a day and then continued the same training twice a month at his home.</p> <p>Results</p> <p>After the training, the error rate of the EEG classification decreased from 40% to 28%. The subject successfully walked around in the VR using only his MI and chatted with other users through a voice-chat function embedded in the internet-based VR. With this improvement in BCI control, event-related desynchronization (ERD) following MI was significantly enhanced (<it>p </it>< 0.01) for feet MI (from -29% to -55%), left-hand MI (from -23% to -42%), and right-hand MI (from -22% to -51%).</p> <p>Conclusions</p> <p>These results show that our subject with severe MD was able to learn to control his EEG signal and communicate with other users through use of VR navigation and suggest that an internet-based VR has the potential to provide paralyzed people with the opportunity for easy communication.</p
Nutrition Strategies for Triathlon
Contemporary sports nutrition guidelines recommend that each athlete develop a personalised, periodised and practical approach to eating that allows him or her to train hard, recover and adapt optimally, stay free of illness and injury and compete at their best at peak races. Competitive triathletes undertake a heavy training programme to prepare for three different sports while undertaking races varying in duration from 20 min to 10 h. The everyday diet should be adequate in energy availability, provide CHO in varying amounts and timing around workouts according to the benefits of training with low or high CHO availability and spread high-quality protein over the day to maximise the adaptive response to each session. Race nutrition requires a targeted and well-practised plan that maintains fuel and hydration goals over the duration of the specific event, according to the opportunities provided by the race and other challenges, such as a hot environment. Supplements and sports foods can make a small contribution to a sports nutrition plan, when medical supplements are used under supervision to prevent/treat nutrient deficiencies (e.g. iron or vitamin D) or when sports foods provide a convenient source of nutrients when it is impractical to eat whole foods. Finally, a few evidence-based performance supplements may contribute to optimal race performance when used according to best practice protocols to suit the triathlete’s goals and individual responsiveness
Turbulent ‘stopping plumes’ and plume pinch-off in uniform surroundings
Observations of turbulent convection in the environment are of variously sus- tained plume-like flows or intermittent thermal-like flows. At different times of the day the prevailing conditions may change and consequently the observed flow regimes may change. Understanding the link between these flows is of practical importance meteorologically, and here we focus our interest upon plume-like regimes that break up to form thermal-like regimes. It has been shown that when a plume rises from a boundary with low conductivity, such as arable land, the inability to maintain a rapid enough supply of buoyancy to the plume source can result in the turbulent base of the plume separating and rising away from the source. This plume ‘pinch-off’ marks the onset of the intermittent thermal-like behavior. The dynamics of turbulent plumes in a uniform environment are explored in order to investigate the phenomenon of plume pinch-off. The special case of a turbulent plume having its source completely removed, a ‘stopping plume’, is considered in particular. The effects of forcing a plume to pinch-off, by rapidly reducing the source buoyancy flux to zero, are shown experi- mentally. We release saline solution into a tank filled with fresh water generating downward propagating steady turbulent plumes. By rapidly closing the plume nozzle, the plumes are forced to pinch-off. The plumes are then observed to detach from the source and descend into the ambient. The unsteady buoyant region produced after pinch-off, cannot be described by the power-law behavior of either classical plumes or thermals, and so the terminology ‘stopping plume’ (analogous to a ‘starting plume’) is adopted for this type of flow. The propagation of the stopping plume is shown to be approximately linearly dependent on time, and we speculate therefore that the closure of the nozzle introduces some vorticity into the ambient, that may roll up to form a vortex ring dominating the dynamics of the base of a stopping plume
Workload capacity spaces: A unified methodology for response time measures of efficiency as workload is varied
The construction of an idealised urban masculinity among men with concurrent sexual partners in a South African township
Background : The perspectives of heterosexual males who have large sexual networks comprising concurrent sexual partners and who engage in high-risk sexual behaviours are scarcely documented. Yet these perspectives are crucial to understanding the high HIV prevalence in South Africa where domestic violence, sexual assault and rape are alarmingly high, suggesting problematic gender dynamics. Objective : To explore the construction of masculinities and men's perceptions of women and their sexual relationships, among men with large sexual networks and concurrent partners. Design : This qualitative study was conducted in conjunction with a larger quantitative survey among men at high risk of HIV, using respondent-driven sampling to recruit participants, where long referral chains allowed us to reach far into social networks. Twenty in-depth, open-ended interviews with South African men who had multiple and concurrent sexual partners were conducted. A latent content analysis was used to explore the characteristics and dynamics of social and sexual relationships. Results : We found dominant masculine ideals characterised by overt economic power and multiple sexual partners. Reasons for large concurrent sexual networks were the perception that women were too empowered, could not be trusted, and lack of control over women. Existing masculine norms encourage concurrent sexual networks, ignoring the high risk of HIV transmission. Biological explanations and determinism further reinforced strong and negative perceptions of women and female sexuality, which helped polarise men's interpretation of gender constructions. Conclusions : Our results highlight the need to address sexuality and gender dynamics among men in growing, informal urban areas where HIV prevalence is strikingly high. Traditional structures that could work as focal entry points should be explored for effective HIV prevention aimed at normative change among hard-to-reach men in high-risk urban and largely informal contexts
Cancer incidence patterns by region and socioeconomic deprivation in teenagers and young adults in England
Data on 35 291 individuals with cancer, aged 13–24 years, in England from 1979 to 2001 were analysed by region and socio-economic deprivation of census ward of residence, as measured by the Townsend deprivation index. The incidence of leukaemia, lymphoma, central nervous system tumours, soft tissue sarcomas, gonadal germ cell tumours, melanoma and carcinomas varied by region (P<0.01, all groups) but bone tumour incidence did not. Lymphomas, central nervous system tumours and gonadal germ cell tumours all had higher incidence in less deprived census wards (P<0.01), while chronic myeloid leukaemia and carcinoma of the cervix had higher incidence in more deprived wards (P<0.01). In the least deprived wards, melanoma incidence was nearly twice that in the most deprived, but this trend varied between regions (P<0.001). These cancer incidence patterns differ from those seen in both children and older adults and have implications for aetiology and prevention
Food effects on statolith composition of the common cuttlefish (Sepia officinalis)
The concentration of trace elements within cephalopod statoliths can provide a record of the environmental characteristics at the time of calcification. To reconstruct accurately the environmental characteristics at the time of calcification, it is important to understand the influence of as many factors as possible. To test the hypothesis that the elemental composition of cuttlefish statoliths could be influenced by diet, juvenile Sepia officinalis were fed either shrimp Crangon sp. or fish Clupea harengus under equal temperature and salinity regimes in laboratory experiments. Element concentrations in different regions of the statoliths (core–lateral dome–rostrum) were determined using laser ablation inductively coupled plasma mass spectrometry (LA- ICPMS). The ratios of Sr/Ca, Ba/Ca, Mn/Ca and Y/Ca in the statolith’s lateral dome of shrimp-fed cuttlefish were significantly higher than in the statolith’s lateral dome of fish-fed cuttlefish. Moreover, significant differences between statolith regions were found for all analysed elements. The fact that diet adds a considerable variation especially to Sr/Ca and Ba/Ca must be taken into account in future micro-chemical statolith studies targeting cephalopod’s life history
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