Well-tempered n-plet dark matter

We study simple effective models of fermionic WIMP dark matter, where the dark matter candidate is a mixture of a Standard Model singlet and an n-plet of SU(2) with n >= 3, stabilized by a discrete symmetry. The dark matter mass is assumed to be around the electroweak scale, and the mixing is generated by higher-dimensional operators, with a cutoff scale > 1 TeV. For appropriate values of the mass parameters and the mixing we find that the observed dark matter relic density can be generated by coannihilation. Direct detection experiments have already excluded large parts of the parameter space, and the next-generation experiments will further constrain these models.Comment: 25 pages, 7 figures; v2: references and plots updated, minor corrections, conclusions unchange

Mindfulness May Moderate the Relationship Between Intrinsic Motivation and Physical Activity: A Cross-Sectional Study

International audienceThis study aims to characterize the relationships between intrinsic motivation towards physical activity, mindfulness, and physical activity level. We measured self-reported mindfulness, motivational regulation towards exercise, and physical activity level in 280 French students. Analyses conducted on 244 participants revealed that self-reported mindfulness moderates the relationship between intrinsic motivation towards exercise and physical activity levels. These findings may have implications for interventionists seeking to promote increased physical activity with mindfulness-based techniques. In fact, it seems that increasing mindfulness skills of individuals could improve their intrinsic motivation to exercise and thus, physical activity

A Cognitive and Virtual Reality Treatment Program for the Fear of Flying

International audienceBACKGROUND: Passenger air transport has considerably increased in the past 50 yr. It is estimated that between 7 and 40% of the population of industrialized countries is currently afraid of flying. Programs treating the fear of flying have been developed to meet this problem. This study measures the effectiveness of one of these programs by focusing on flight-related anxiety before the program and after the first flight following the intervention.METHODS: There were 157 individuals recruited to participate in a 1-d intervention aiming at treating the fear of flying, and using both cognitive behavioral techniques and virtual reality. Anxiety was measured with the Flight Anxiety Situations (FAS) and the Flight Anxiety Modality (FAM) questionnaires.RESULTS: Statistical analyses were conducted on 145 subjects (69.7% female; ages from 14 to 64) after the exclusion of individuals with missing data. The results showed a decrease in flight-related anxiety for each subscale of the two questionnaires: the somatic (d = 2.44) and cognitive anxiety (d = 1.47) subscales of the FAM, and the general flight anxiety (d = 3.20), the anticipatory flight anxiety (d = 1.74), and the in-flight anxiety (d = 1.04) subscales of the FAS.CONCLUSIONS: The effectiveness of the treatment program using both cognitive behavioral techniques and virtual reality strategies for fear of flying reduced flight-related anxiety in the subjects in our study. Our results show that subjects demonstrated lower anxiety levels after the first flight following the program than before the intervention

Global warming reshapes European pyroregions

Wildland fire is expected to increase in response to global warming, yet little is known about future changes to fire regimes in Europe. Here, we developed a pyrogeography based on statistical fire models to better understand how global warming reshapes fire regimes across the continent. We identified five large-scale pyroregions with different levels of area burned, fire frequency, intensity, length of fire period, size distribution, and seasonality. All other things being equal, global warming was found to alter the distribution of these pyroregions, with an expansion of the most fire prone pyroregions ranging respectively from 50% to 130% under 2° and 4°C global warming scenarios. Our estimates indicate a strong amplification of fire across parts of southern Europe and a subsequent shift toward new fire regimes, implying substantial socio-ecological impacts in the absence of mitigation or adaptation measures

Teashirt 1 (Tshz1) is essential for the development, survival and function of hypoglossal and phrenic motor neurons in mouse

Feeding and breathing are essential motor functions and rely on the activity of hypoglossal and phrenic motor neurons that innervate the tongue and diaphragm, respectively. Little is known about the genetic programs that control the development of these neuronal subtypes. The transcription factor Tshz1 is strongly and persistently expressed in developing hypoglossal and phrenic motor neurons. We used conditional mutation of Tshz1 in the progenitor zone of motor neurons (Tshz1(MNΔ)) to show that Tshz1 is essential for survival and function of hypoglossal and phrenic motor neurons. Hypoglossal and phrenic motor neurons are born in correct numbers, but many die between embryonic day 13.5 and 14.5 in Tshz1(MNΔ) mutant mice. In addition, innervation and electrophysiological properties of phrenic and hypoglossal motor neurons are altered. Severe feeding and breathing problems accompany this developmental deficit. Although motor neuron survival can be rescued by elimination of the pro-apoptotic factor Bax, innervation, feeding and breathing defects persist in Bax(-/-); Tshz1(MNΔ) mutants. We conclude that Tshz1 is an essential transcription factor for the development and physiological function of phrenic and hypoglossal motor neurons

The effects of mindfulness training on weight-loss and health-related behaviours in adults with overweight and obesity: A systematic review and meta-analysis

The aim of this study was to conduct a comprehensive quantitative synthesis of the effects of mindfulness training interventions on weight-loss and health behaviours in adults with overweight and obesity using meta-analytic techniques. Studies included in the analysis (k =12) were randomised controlled trials investigating the effects of any form of mindfulness training on weight loss, impulsive eating, binge eating, or physical activity participation in adults with overweight and obesity. Random effects meta-analysis revealed that mindfulness training had no significant effect on weight loss, but an overall negative effect on impulsive eating (d =-1.13) and binge eating (d =-.90), and a positive effect on physical activity levels (d =.42). Meta-regression analysis showed that methodological features of included studies accounted for 100% of statistical heterogeneity of the effects of mindfulness training on weight loss (R 2 =1,00). Among methodological features, the only significant predictor of weight loss was follow-up distance from post-intervention (ß =1.18; p <.05), suggesting that the longer follow-up distances were associated with greater weight loss. Results suggest that mindfulness training has short-term benefits on health-related behaviours. Future studies should explore the effectiveness of mindfulness training on long-term post-intervention weight loss in adults with overweight and obesity

Human prostate supports more efficient replication of HIV-1 R5 than X4 strains ex vivo

<p>Abstract</p> <p>Background</p> <p>In order to determine whether human prostate can be productively infected by HIV-1 strains with different tropism, and thus represent a potential source of HIV in semen, an organotypic culture of prostate from men undergoing prostatic adenomectomy for benign prostate hypertrophy (BPH) was developed. The presence of potential HIV target cells in prostate tissues was investigated using immunohistochemistry. The infection of prostate explants following exposures with HIV-1 R5, R5X4 and X4 strains was analyzed through the measure of RT activity in culture supernatants, the quantification of HIV DNA in the explants and the detection of HIV RNA+ cells <it>in situ</it>.</p> <p>Results</p> <p>The overall prostate characteristics were retained for 2^1/2weeks in culture. Numerous potential HIV-1 target cells were detected in the prostate stroma. Whilst HIV-1 R5_SF162strain consistently productively infected prostatic T lymphocytes and macrophages, the prototypic X4_IIIBstrain and a primary R5X4 strain showed less efficient replication in this organ.</p> <p>Conclusion</p> <p>The BPH prostate is a site of HIV-1 R5 replication that could contribute virus to semen. A limited spreading of HIV-1 X4 and R5X4 in this organ could participate to the preferential sexual transmission of HIV-1 R5 strains.</p

SurEau-Ecos v2.0: a trait-based plant hydraulics model for simulations of plant water status and drought-induced mortality at the ecosystem level

A widespread increase in tree mortality has been observed around the globe, and this trend is likely to continue because of ongoing climate-induced increases in drought frequency and intensity. This raises the need to identify regions and ecosystems that are likely to experience the most frequent and significant damage. We present SurEau-Ecos, a trait-based, plant hydraulic model designed to predict tree desiccation and mortality at scales from stand to region. SurEau-Ecos draws on the general principles of the SurEau model but introduces a simplified representation of plant architecture and alternative numerical schemes. Both additions were made to facilitate model parameterization and large-scale applications. In SurEau-Ecos, the water fluxes from the soil to the atmosphere are represented through two plant organs (a leaf and a stem, which includes the volume of the trunk, roots and branches) as the product of an interface conductance and the difference between water potentials. Each organ is described by its symplasmic and apoplasmic compartments. The dynamics of a plant's water status beyond the point of stomatal closure are explicitly represented via residual transpiration flow, plant cavitation and solicitation of plants' water reservoirs. In addition to the “explicit” numerical scheme of SurEau, we implemented a “semi-implicit” and “implicit” scheme. Both schemes led to a substantial gain in computing time compared to the explicit scheme (&gt;10 000 times), and the implicit scheme was the most accurate. We also observed similar plant water dynamics between SurEau-Ecos and SurEau but slight disparities in infra-daily variations of plant water potentials, which we attributed to the differences in the representation of plant architecture between models. A global model's sensitivity analysis revealed that factors controlling plant desiccation rates differ depending on whether leaf water potential is below or above the point of stomatal closure. Total available water for the plant, leaf area index and the leaf water potential at 50 % stomatal closure mostly drove the time needed to reach stomatal closure. Once stomata are closed, resistance to cavitation, residual cuticular transpiration and plant water stocks mostly determined the time to hydraulic failure. Finally, we illustrated the potential of SurEau-Ecos to simulate regional drought-induced mortality over France. SurEau-Ecos is a promising tool to perform regional-scale predictions of drought-induced hydraulic failure, determine the most vulnerable areas and ecosystems to drying conditions, and assess the dynamics of forest flammability.</p

Harcèlement et abus (violence non accidentelle) dans le sport : synthèse ReFORM de la position de consensus du Comité International Olympique

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