Fluctuation-Driven Neural Dynamics Reproduce Drosophila Locomotor Patterns.

The neural mechanisms determining the timing of even simple actions, such as when to walk or rest, are largely mysterious. One intriguing, but untested, hypothesis posits a role for ongoing activity fluctuations in neurons of central action selection circuits that drive animal behavior from moment to moment. To examine how fluctuating activity can contribute to action timing, we paired high-resolution measurements of freely walking Drosophila melanogaster with data-driven neural network modeling and dynamical systems analysis. We generated fluctuation-driven network models whose outputs-locomotor bouts-matched those measured from sensory-deprived Drosophila. From these models, we identified those that could also reproduce a second, unrelated dataset: the complex time-course of odor-evoked walking for genetically diverse Drosophila strains. Dynamical models that best reproduced both Drosophila basal and odor-evoked locomotor patterns exhibited specific characteristics. First, ongoing fluctuations were required. In a stochastic resonance-like manner, these fluctuations allowed neural activity to escape stable equilibria and to exceed a threshold for locomotion. Second, odor-induced shifts of equilibria in these models caused a depression in locomotor frequency following olfactory stimulation. Our models predict that activity fluctuations in action selection circuits cause behavioral output to more closely match sensory drive and may therefore enhance navigation in complex sensory environments. Together these data reveal how simple neural dynamics, when coupled with activity fluctuations, can give rise to complex patterns of animal behavior.

New insight in the relationship between regional patterns of knee cartilage thickness, osteoarthritis disease severity, and gait mechanics.

To test if the relationship between knee kinetics during walking and regional patterns of cartilage thickness is influenced by disease severity we tested the following hypotheses in a cross-sectional study of medial compartment osteoarthritis (OA) subjects: (1) the peak knee flexion (KFM) and adduction moments (KAM) during walking are associated with regional cartilage thickness and medial-to-lateral cartilage thickness ratios, and (2) the associations between knee moments and cartilage thickness data are dependent on disease severity. Seventy individuals with medial compartment knee OA were studied. Gait analysis was used to determine the knee moments and cartilage thickness was measured from magnetic resonance imaging. Multiple linear regression analyses tested for associations between cartilage thickness and knee kinetics. Medial cartilage thickness and medial-to-lateral cartilage thickness ratios were lower in subjects with greater KAM for specific regions of the femoral condyle and tibial plateau with no associations for KFM in patients of all disease severities. When separated by severity, the association between KAM and cartilage thickness was found only in patients with more severe OA, and KFM was significantly associated with cartilage thickness only for the less severe OA subjects for specific tibial plateau regions. The results support the idea that the KAM is larger in patients with more severe disease and the KFM has greater influence early in the disease process, which may lessen as pain increases with disease severity. Each component influences different regions of cartilage. Thus the relative contributions of both KAM and KFM should be considered when evaluating gait mechanics and the influence of any intervention for knee OA.

Patterns of variability of retinol levels in a harbour porpoise population from an unpolluted environment

Organochlorine compounds (OC) are known to induce vitamin A (retinoids) deficiency in mammals, which may be associated with impairment of immunocompetence, reproduction and growth. This makes retinoids a potentially useful biomarker of organochlorine impact on marine mammals. However, use of retinoids as a biomarker requires knowledge about its intrapopulation patterns of variation in natural conditions, information which is not currently available. We investigated these patterns in a cetacean population living in an unpolluted environment. 100 harbour porpoises Phocoena phocoena from West Greenland were sampled during the 1995 hunting season. Sex, age, morphometrics, nutritive condition, and retinol (following saponification) and OC levels in blubber were determined for each individual. OC levels found were extremely low and therefore considered unlikely to affect the population adversely: mean blubber concentrations, expressed on an extractable basis, were 2.04 (SD = 1.1) ppm for PCBs and 2.76 (SD = 1.66) ppm for tDDT. The mean blubber retinol concentration for the overall population was 59.66 (SD = 45.26) mu g g(-1). Taking into account the high contribution of blubber to body mass, blubber constitutes a significant body site for retinoid deposition in harbour porpoises. Retinol concentrations did not differ significantly between geographical regions or sexes, but they did correlate significantly (p <0.001) with age. Body condition, measured by determining the lipid content of the blubber, did not have a significant effect on retinol levels but the individuals examined were considered to be in an overall good nutritive condition. It is concluded that measurement of retinol concentrations in blubber samples is feasible and has a potential for use as a biomarker of organochlorine exposure in cetaceans. However, in order to do so, biological information, particularly age, is critical for the correct assessment of physiological impact

Patterns of care in recurrent glioblastoma in Switzerland: a multicentre national approach based on diagnostic nodes.

Despite moderate improvements in outcome of glioblastoma after first-line treatment with chemoradiation recent clinical trials failed to improve the prognosis of recurrent glioblastoma. In the absence of a standard of care we aimed to investigate institutional treatment strategies to identify similarities and differences in the pattern of care for recurrent glioblastoma. We investigated re-treatment criteria and therapeutic pathways for recurrent glioblastoma of eight neuro-oncology centres in Switzerland having an established multidisciplinary tumour-board conference. Decision algorithms, differences and consensus were analysed using the objective consensus methodology. A total of 16 different treatment recommendations were identified based on combinations of eight different decision criteria. The set of criteria implemented as well as the set of treatments offered was different in each centre. For specific situations, up to 6 different treatment recommendations were provided by the eight centres. The only wide-range consensus identified was to offer best supportive care to unfit patients. A majority recommendation was identified for non-operable large early recurrence with unmethylated MGMT promoter status in the fit patients: here bevacizumab was offered. In fit patients with late recurrent non-operable MGMT promoter methylated glioblastoma temozolomide was recommended by most. No other majority recommendations were present. In the absence of strong evidence we identified few consensus recommendations in the treatment of recurrent glioblastoma. This contrasts the limited availability of single drugs and treatment modalities. Clinical situations of greatest heterogeneity may be suitable to be addressed in clinical trials and second opinion referrals are likely to yield diverging recommendations.

Geography of talent and regional differences in Spain

Tentative empirical evidence suggests that the agglomeration of talent contributes to regional development. However, given that talented people are not evenly distributed across regions, this paper seeks to determine how the concentration of talent affects patterns of regional development. Here, we empirically evaluate the effects of the distribution of talent on regional differences by means of a detailed analysis of the 17 Autonomous Communities of Spain between 1996 and 2004. We hypothesise that regions specialising in strategic sectors that are creative and which can be assumed to enjoy rapid growth in productivity will experience faster rates of development and, in turn, that this concentration of talent will have a positive impact on the region’s economic performance. Thus, we believe that this mechanism can explain the marked regional imbalances in Spain. Our findings confirm that regional differences, measured in terms of GDP per capita and by, - industrial and service- oriented production, are influenced by the Communities’ talent bases as determined by, educational attainment and employment in assumed to be strategic for regional development, inasmuch as these sectors provide economic specialization.

How to describe species richness patterns for bryophyte conservation?

A large amount of data for inconspicuous taxa is stored in natural history collections; however, this information is often neglected for biodiversity patterns studies. Here, we evaluate the performance of direct interpolation of museum collections data, equivalent to the traditional approach used in bryophyte conservation planning, and stacked species distribution models (S-SDMs) to produce reliable reconstructions of species richness patterns, given that differences between these methods have been insufficiently evaluated for inconspicuous taxa. Our objective was to contrast if species distribution models produce better inferences of diversity richness than simply selecting areas with the higher species numbers. As model species, we selected Iberian species of the genus Grimmia (Bryophyta), and we used four well-collected areas to compare and validate the following models: 1) four Maxent richness models, each generated without the data from one of the four areas, and a reference model created using all of the data and 2) four richness models obtained through direct spatial interpolation, each generated without the data from one area, and a reference model created with all of the data. The correlations between the partial and reference Maxent models were higher in all cases (0.45 to 0.99), whereas the correlations between the spatial interpolation models were negative and weak (-0.3 to -0.06). Our results demonstrate for the first time that S-SDMs offer a useful tool for identifying detailed richness patterns for inconspicuous taxa such as bryophytes and improving incomplete distributions by assessing the potential richness of under-surveyed areas, filling major gaps in the available data. In addition, the proposed strategy would enhance the value of the vast number of specimens housed in biological collections.

Phylogeography of competing sexual and parthenogenetic forms of a freshwater flatworm: patterns and explanations

Background: Models of the maintenance of sex predict that one reproductive strategy, sexual or parthenogenetic, should outcompete the other. Distribution patterns may reflect the outcome of this competition as well as the effect of chance and historical events. We review the distribution data of sexual and parthenogenetic biotypes of the planarian Schmidtea polychroa. Results: S. polychroa lives in allopatry or sympatry across Europe except for Central and North-Western Europe, where sexual individuals have never been reported. A phylogenetic relationship between 36 populations based on a 385 bp fragment of the mitochondrial cytochrome oxidase I gene revealed that haplotypes were often similar over large geographic distances. In North Italian lakes, however, diversity was extreme, with sequence differences of up to 5% within the same lake in both sexuals and parthenogens. Mixed populations showed "endemic" parthenogenetic lineages that presumably originated from coexisting sexuals, and distantly related ones that probably result from colonization by parthenogens independent from sexuals. Conclusions: Parthenogens originated repeatedly from sexuals, mainly in Italy, but the same may apply to other Mediterranean regions (Spain, Greece). The degree of divergence between populations suggests that S. polychroa survived the ice ages in separate ice-free areas in Central, Eastern and Southern Europe and re-colonised Europe after the retreat of the major glaciers. Combining these results with those based on nuclear markers, the data suggest that repeated hybridisation between sexuals and parthenogenetic lineages in mixed populations maintains high levels of genetic diversity in parthenogens. This can explain why parthenogens persist in populations that were originally sexual. Exclusive parthenogenesis in central and western populations suggests better colonisation capacity, possibly because of inbreeding costs as well

Temporal Patterns of Alcohol Consumption and Alcohol-Related Road Accidents in Young Swiss Men: Seasonal, Weekday and Public Holiday Effects.

AIMS: To assess seasonal, weekday, and public holiday effects on alcohol-related road accidents and drinking diaries among young Swiss men. METHODS: Federal road accident data (35,485 accidents) from Switzerland and drinking diary data from a large cohort of young Swiss men (11,930 subjects) were analysed for temporal effects by calendar week, weekday and public holiday (Christmas, New Years, National Day). Alcohol-related accidents were analysed using rate ratios for observed versus expected numbers of accidents and proportions of alcohol-related accidents relative to the total number. Drinking diaries were analysed for the proportion of drinkers, median number of drinks consumed, and the 90th percentile's number of drinks consumed. RESULTS: Several parallel peaks were identified in alcohol-related accidents and drinking diaries. These included increases on Fridays and Saturdays, with Saturday drinking extending until early Sunday morning, an increase during the summer on workdays but not weekends, an increase at the end of the year, and increases on public holidays and the evening before. CONCLUSIONS: Our results suggest specific time-windows that are associated with increases in drinking and alcohol-related harm. Established prevention measures should be enforced during these time-windows to reduce associated peaks.

Epidemiology and injury patterns of patients consulting following assault by nightclub security agents in a university hospital emergency service and an associated specialised forensic consultation

Introduction: The Violence Medical Unit (VMU), a specialised forensic medical consultation, was created at the Lausanne university Hospital in 2006. All patients consulting at the ED for interpersonal violencerelated injury are referred to the VMU, which provides forensic documentation of the injury and referral to the relevant community based victim-support organisations within 48 hours of the ED visit. This frees the ED medical staff from forensic injury documentation and legal/social referral, tasks for which they lack both time and training. Among community violence, assaults by nightclub security agents against patrons have increased from 6% to 10% between 2007 and 2009. We set out to characterise the demographics, assault mechanisms, subsequent injuries, prior alcohol intake and ED & VMU costs incurred by this group of patients. Methods: We retrospectively included all patients consulting at the VMU due to assault by nightclub security agents from January 2007 to December 2009. Data was obtained from ED & VMU medical, nursing and administrative records. Results: Our sample included 70 patients, of which 64 were referred by the CHUV ED. The victims were typically young (median age 29) males (93%). 77% of assaults occurred on the weekend between 12 PM and 4 AM, and 73% of the victims were under the influence of alcohol. 83% of the patients were punched, kicked and/or head-butted; 9% had been struck with a blunt instrument. 80% of the injuries were in the head and neck area and 19% of the victims sustained fractures. 21% of the victims were prescribed medical leave. Total ED & VMU costs averaged 1048 SFr. Conclusion: Medical staff treating this population of assault victims must be aware of the assault mechanisms and injury patterns, in particular the high probability of fractures, in order to provide adequate diagnosis and care. Associated inebriation mandates liberal use of radiology, as delayed or missed diagnosis may have medical, medicolegal and legal implications. Emergency medical services play an important role in detecting and reporting of such incidents. Centralised management of the forensic documentation facilitates referral to victim support organisations and epidemiological data collection. Magnitudes and trends of the different types of violence can be determined, and this information can be then impact public safety management policies.

Identification of imaging selection patterns in acute ischemic stroke patients and the influence on treatment and clinical trial enrollment decision making.

BACKGROUND AND PURPOSE: For the STroke Imaging Research (STIR) and VISTA-Imaging Investigators The purpose of this study was to collect precise information on the typical imaging decisions given specific clinical acute stroke scenarios. Stroke centers worldwide were surveyed regarding typical imaging used to work up representative acute stroke patients, make treatment decisions, and willingness to enroll in clinical trials. METHODS: STroke Imaging Research and Virtual International Stroke Trials Archive-Imaging circulated an online survey of clinical case vignettes through its website, the websites of national professional societies from multiple countries as well as through email distribution lists from STroke Imaging Research and participating societies. Survey responders were asked to select the typical imaging work-up for each clinical vignette presented. Actual images were not presented to the survey responders. Instead, the survey then displayed several types of imaging findings offered by the imaging strategy, and the responders selected the appropriate therapy and whether to enroll into a clinical trial considering time from onset, clinical presentation, and imaging findings. A follow-up survey focusing on 6 h from onset was conducted after the release of the positive endovascular trials. RESULTS: We received 548 responses from 35 countries including 282 individual centers; 78% of the centers originating from Australia, Brazil, France, Germany, Spain, United Kingdom, and United States. The specific onset windows presented influenced the type of imaging work-up selected more than the clinical scenario. Magnetic Resonance Imaging usage (27-28%) was substantial, in particular for wake-up stroke. Following the release of the positive trials, selection of perfusion imaging significantly increased for imaging strategy. CONCLUSIONS: Usage of vascular or perfusion imaging by Computed Tomography or Magnetic Resonance Imaging beyond just parenchymal imaging was the primary work-up (62-87%) across all clinical vignettes and time windows. Perfusion imaging with Computed Tomography or Magnetic Resonance Imaging was associated with increased probability of enrollment into clinical trials for 0-3 h. Following the release of the positive endovascular trials, selection of endovascular only treatment for 6 h increased across all clinical vignettes.

Managing induced tourism image : relational patterns and the life cycle

The tourism image is an element that conditions the competitiveness of tourism destinations by making them stand out in the minds of tourists. In this context, marketers of tourism destinations endeavour to create an induced image based on their identity and distinctive characteristics.A number of authors have also recognized the complexity of tourism destinations and the need for coordination and cooperation among all tourism agents, in order to supply a satisfactory tourist product and be competitive in the tourism market. Therefore, tourism agents at the destination need to develop and integrate strategic marketing plans.The aim of this paper is to determine how cities of similar cultures use their resources with the purpose of developing a distinctive induced tourism image to attract tourists and the extent of coordination and cooperation among the various tourism agents of a destination in the process of induced image creation.In order to accomplish these aims, a comparative analysis of the induced image of two cultural cities is presented, Girona (Spain) and Perpignan (France). The induced image is assessed through the content analysis of promotional brochures and the extent of cooperation with in-depth interviews of the main tourism agents of these destinations.Despite the similarities of both cities in terms of tourism resources, results show the use of different attributes to configure the induced image of each destination, as well as a different configuration of the network of tourism agents that participate in the process of induced image creation

Emergent patterns of social organization in captive Cercocebus torquatus: Testing the GrooFiWorld agent-based model

We empirically applied the GrooFiWorld agent-based model (Puga-González et al. 2009) in a group of captive mangabeys (Cercocebus torquatus). We analysed several measurements related to aggression and affiliative patterns. The group adopted a combination of despotic and egalitarian behaviours resulting from the behavioural flexibility observed in the Cercopithecinae subfamily. Our study also demonstrates that the GrooFiWorld agent-based model can be extended to other members of the Cercopithecinae subfamily generating parsimonious hypotheses related to the social organization.

Institutional legacies, employment and professional integration of non EU/EEA doctors in France

Internationally, policies for attracting highly-skilled migrants have become the guidelines mainly used by the Organisation for Economic Co-operation and Development (OECD) countries. Governments are implementing specific procedures to capture and facilitate their mobility. However, all professions are not equal when it comes to welcoming highly-skilled migrants. The medical profession, as a protective market, is one of these. Taking the case of non-EU/EEA doctors in France, this paper shows that the medical profession defined as the closed labour market, remains the most controversial in terms of professional integration of migrants, protectionist barriers to migrant competition and challenge of medical shortage. Based on the path-dependency approach, this paper argues that non-EU/EEA doctors' issues in France derive from a complex historical process of interaction between standards settled in the past, particularly the historical power of medical corporatism, the unexpected long-term effects of French hospital reforms of 1958, and budgetary pressures. Theoretically, this paper shows two significant findings. Firstly, the French medical system has undergone a series of transformations unthinkable in the strict sense of a path-dependence approach: an opening of the medical profession to foreign physicians in the context of the Europeanisation of public policy, acceptance of non-EU/EEA doctors in a context of medical shortage and budgetary pressures. Secondly, there is no change of the overall paradigm: significantly, the recruitment policies of non-EU/EEA doctors continue to highlight the imprint of the past and reveal a significant persistence of prejudices. Non-EU/EEA doctors are not considered legitimate doctors even if they have the qualifications of physicians which are legitimate in their country and which can be recognised in other receiving countries.