4,840 research outputs found

    Hybrid Superconducting Neutron Detectors

    Full text link
    A new neutron detection concept is presented that is based on superconductive niobium (Nb) strips coated by a boron (B) layer. The working principle of the detector relies on the nuclear reaction 10B+n →\rightarrow α\alpha+ 7Li , with α\alpha and Li ions generating a hot spot on the current-biased Nb strip which in turn induces a superconducting-normal state transition. The latter is recognized as a voltage signal which is the evidence of the incident neutron. The above described detection principle has been experimentally assessed and verified by irradiating the samples with a pulsed neutron beam at the ISIS spallation neutron source (UK). It is found that the boron coated superconducting strips, kept at a temperature T = 8 K and current-biased below the critical current Ic, are driven into the normal state upon thermal neutron irradiation. As a result of the transition, voltage pulses in excess of 40 mV are measured while the bias current can be properly modulated to bring the strip back to the superconducting state, thus resetting the detector. Measurements on the counting rate of the device are presented and the future perspectives leading to neutron detectors with unprecedented spatial resolutions and efficiency are highlighted.Comment: 8 pages 6 figure

    Effect of platelet lysate on uterine response of mares susceptible to persistent mating-induced endometritis

    Get PDF
    Many mares are susceptible to persistent mating-induced endometritis (PMIE), an important cause of reduced fertility. Platelet lysate (PL) derives from freeze-thawing platelets after concentration, so that growth factors are released from the platelets. Among the advantages of PL compared to platelet-rich plasma (PRP), it can be frozen stored and allogenic use for PL might also be conceivable. Platelet-rich plasma beneficially reduced inflammatory response in PMIE mares when administered 24 h pre- or 4 h post-AI. The aim of this study was to test the effect of PL on inflammatory uterine response in mares susceptible to PMIE. A total of 14 mares susceptible to PMIE (based on presence of fluid or inflammatory cells 24 h after AI) underwent an untreated (Ctr) cycle followed by a treated (PL) cycle. From each mare, 100 mL of citrated whole blood was obtained for PRP production by centrifugation. The resultant PRP was brought to a final volume of 10 mL with platelet poor plasma and frozen at −80 °C to obtain PL. On untreated cycles, mares were inseminated with frozen-thawed semen 36 h after ovulation induction. On treated cycles, PL was thawed, infused into the uterus 12 h after ovulation induction, and AIs were performed 24 h later. The number of neutrophils in uterine cytology (score 1(normal)-3(severe inflammation)) evaluated by optical microscopy, uterine fluid accumulation (height x width) and uterine edema (score 0–3) observed in ultrasonography, were analysed. Pregnancy was evaluated by ultrasonography 14 days after ovulation. A significant decrease (P < 0.05) was observed on cytology score (PL 1.3 ± 0.1 vs Ctr 2.0 ± 0.1), fluid accumulation (PL 79.5 ± 30.1 mm2 vs Ctr 342.7 ± 52.9 mm2) and edema score (PL 1.8 ± 0.2 vs Ctr 2.3 ± 0.2) in treated mares. Pregnancy rate in PL-treated cycles (3/12) and control cycles (2/14), were not significantly different (P > 0.05). According to the results, we conclude that treatment with PL in mares classified as susceptible to PMIE appears to reduce the inflammatory response after breeding, based on clinical signs of uterine edema, IUF accumulation and PMNs migration

    Interference with the Cannabinoid Receptor CB1R Results in Miswiring of GnRH3 and AgRP1 Axons in Zebrafish Embryos

    Get PDF
    The G protein-coupled cannabinoid receptors type 1 (CB1R) and type 2 (CB2R), and their endocannabinoid (eCBs) ligands, have been implicated in several aspects of brain wiring during development. Here we aim to assess whether interfering with CB1R affects development, neuritogenesis and pathfinding of GnRH and AgRP neurons, forebrain neurons that control respectively reproduction and appetite. We pharmacologically and genetically interfered with CB1R in zebrafish strains with fluorescently labeled GnRH3 and the AgRP1 neurons. By applying CB1R antagonists we observed a reduced number of GnRH3 neurons, fiber misrouting and altered fasciculation. Similar phenotypes were observed by CB1R knockdown. Interfering with CB1R also resulted in a reduced number, misrouting and poor fasciculation of the AgRP1 neuron’s axonal projections. Using a bioinformatic approach followed by qPCR validation, we have attempted to link CB1R functions with known guidance and fasciculation proteins. The search identified stathmin-2, a protein controlling microtubule dynamics, previously demonstrated to be coexpressed with CB1R and now shown to be downregulated upon interference with CB1R in zebrafish. Together, these results raise the likely possibility that embryonic exposure to low doses of CB1R-interfering compounds could impact on the development of the neuroendocrine systems controlling sexual maturation, reproduction and food intake

    The electrocardiogram in the diagnosis and management of patients with dilated cardiomyopathy.

    Get PDF
    The term dilated cardiomyopathy (DCM) defines a heterogeneous group of cardiac disorders, which are characterized by left ventricular or biventricular dilatation and systolic dysfunction in the absence of abnormal loading conditions or coronary artery disease sufficient to cause global systolic impairment. In approximately one third of cases, DCM is familial with a genetic pathogenesis and various patterns of inheritance. Although the electrocardiogram (ECG) has been considered traditionally non-specific in DCM, the recently acquired knowledge of the genotype-phenotype correlations provides novel opportunities to identify patterns and abnormalities that may point toward specific DCM subtypes. A learned ECG interpretation in combination with an appropriate use of other ECG-based techniques including ambulatory ECG monitoring, exercise tolerance test and imaging modalities, such as echocardiography and cardiovascular magnetic resonance, may allow the early identification of specific genetic or acquired forms of DCM. Furthermore, ECG abnormalities may reflect the severity of the disease and provide a useful tool in risk stratification and management. In the present review, we discuss the current role of the ECG in the diagnosis and management of DCM. We describe various clinical settings where the appropriate use and interpretation of the ECG can provide invaluable clues, contributing to the important role of this basic tool as cardiovascular medicine evolves

    The TBX3 gene, mutated in Ulnar-Mammary syndrome, promotes growth of mammary epithelial cells independently of ARF and p53.

    Get PDF

    Ultraviolet Completion of Flavour Models

    Full text link
    Effective Flavour Models do not address questions related to the nature of the fundamental renormalisable theory at high energies. We study the ultraviolet completion of Flavour Models, which in general has the advantage of improving the predictivity of the effective models. In order to illustrate the important features we provide minimal completions for two known A4 models. We discuss the phenomenological implications of the explicit completions, such as lepton flavour violating contributions that arise through the exchange of messenger fields.Comment: 18 pages, 8 figure

    THE BEHAVE APPLICATION: AN EVIDENCE-BASED TOOL TO MANAGE SOCIAL EMOTIONAL BEHAVIOURAL DIFFICULTIES

    Get PDF
    Social Emotional and Behavioural Difficulties (SEBD) are a persistent and multiple manifestation of maladaptive behaviours which interfere with the students’ learning, social functioning and development and/or that of their peers. They may become apparent through withdrawn, passive, aggressive or self-injurious tendencies. The prevalence of these disorders is 2-16% of the general population. Children with SEBD, diagnosed or not, are likely to live in social isolation, to receive a poor education, and they risk becoming deviant teenagers, or unemployed adults. A way to approach SEBD with consistent level of educational success is to equip teachers with proper training on practical and proven classroom management strategies, but also with evidence-based tools that can help them to effectively control difficult behaviours with confidence and competence. This contribution presents the web-based BEHAVE application aimed to ease the way for teachers to apply behavioural evidence-based interventions at school. The paper describes the main features of the BEHAVE application: the definition of the behaviour to be observed, the creation and selection of appropriate measures, the collection of behavioural data, and the statistical analysis to evaluate the direction and the power of the effect of the carried-out intervention

    THE BASE SYSTEM: A SCHOOL-WIDE POSITIVE BEHAVIOUR SUPPORT TOOL TO FACILITATE EVIDENCE-BASED DIGITAL INTERVENTION PRACTICES

    Get PDF
    The Positive Behaviour Intervention and Support system is a framework aimed to introduce a change at school-wide level. It promotes a disciplinary system change process, from a reactive punishment- based strategies of specific student misbehaviours to a proactive system, where different behavioural principles such as the modelling and reinforcement of positive prosocial students’ behaviours are applied to improve school values and to create a positive climate. This paper presents the Behavioural Assessment to improve School Environment (BASE) system and the BASE repository. The BASE system supports evidence-based digital intervention practices for stimulating the academic, social, emotional, and behavioural competencies of all students. The BASE repository is a collection of good practices, tools, and instructional contents. Both of the tools are able to support and facilitate, through the use of mobile devices and a web-based responsive system, different prevention and instructional practices at the three-tiers PBS model. At the first level of prevention (Tier 1) the system allows to the school PBS team to define the Expectation Matrix, a set of positive behaviours grouped according to predefined school values and locations. Moreover, the PBS team members are able to define the list of problem behaviours, classifying them in minor and major. The matrix and the list of minor and major problem behaviours are at the base of the development of a screening tool for identifying behavioural risk problems, the Positive Office Referral and the Office Disciplinary Referral tools. At the target prevention level (Tier 2) the BASE application provides the Check-in/Check-out (CICO) tool, as PBIS recommends. It is addressed to a targeted group of students, resulted unresponsive to the Tier I, and implements the practice of ‘Positive reinforcement contingent on meeting behavioural goals’ throughout a reward system. At the intensive prevention level (Tier 3) the system allows users to perform Functional Behaviour Assessment for students considered unresponsive to Tier I and II and to create customized measurement tools for designing single case studies. The measure can be assigned to the observers able to collect data and organize them in phases. A TAU analysis algorithm is applied to the gathered data for showing the effectiveness of intervention. In the BASE application, each student can access to the system with personal credentials and to visualize his significant progresses into a smart dashboard. The BASE repository represents a hub for digital resources collection concerning both theoretical and methodological aspects of the PBIS approach. The Internet users interested to know the European experience of the involved partner schools, and to enlarge their knowledge about the principles to implement the PBIS in their own school, can find a first set of multimedia contents, webinars, collection of good practices gathered during the lifespan of the European Erasmus+ BASE project. The repository facilitates the finding of high-quality contents and represents a learning corner and an important knowledge repository for teachers and health professionals to understand and apply this approach
    • …
    corecore