252 research outputs found

    Teacher-Student Relationships: Strengthening the Impact of PBIS on Climate

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    Researchers have emphasized the importance of teacher-student relationships (TSRs), showing that the quality of these relationships can have significant, short and long-term effects on student outcomes and school climate (Baker, Grant & Morlock, 2008; Guess & Bowling, 2013; Hamre & Pianta, 2001). While School-Wide Positive Behavior Interventions and Supports (SW-PBIS) also has positive effects on school climate (Bradshaw, Waasdorp & Leaf, 2015), little research has been done to examine how SW-PBIS and TSRs intersect to influence student outcomes and school climate. This presentation will address the integration of these two factors as perceived by practitioners responsible for implementing SW-PBIS. Data will be presented from focus group interviews with SW-PBS teams and mental health professionals (N = 178) from three high-need, low-resource school districts in Georgia. Interviews were conducted to understand how participants perceived barriers and facilitators to SW-PBIS. Of specific interest were SW-PBIS team members’ views about how TSRs influence the implementation and efficacy of SW-PBIS, as well as how SW-PBIS implementation influences TSR quality and school climate. Results indicated that TSRs support positive student behavior in a preventative way that is consistent with the goals of SW-PBIS, while the rituals and routines of SW-PBIS also provide opportunities for positive interactions between teachers and students that enhance positive TSRs. Results also provided some evidence that poor TSRs may work against SW-PBIS goals by contributing to an increase in negative student behaviors. Presenters will discuss the implications of this bidirectional relationship for school professionals who want to improve SW-PBIS implementation and/or TSR quality. Implications from results are especially important for schools that serve diverse communities. Our results described how TSRs can be particularly important for the success of SW-PBIS in light of socioeconomic or racial/ethnic diversity within the student body, as it builds perceived trust between teachers, students and families

    The Effect of 17beta Estradiol on Glut1 Expression In The Right Ventricle Of Rats With Severe Pulmonary Hypertension

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    poster abstractPulmonary hypertension (PH) is a devastating disease that is characterized by a rise of blood pressure in the blood vessels of the lung. This puts significant strain on the right ventricle (RV) of the heart. If untreated, PH can lead to right heart failure and death. One of the hallmarks of right heart failure in PH is the development of cytoplasmic glycolysis in the cardiac muscle cells (myocytes) of the RV. This describes a compensatory process where glucose uptake into the mitochondria is inhibited, thereby leading to its conversion to lactate in the cytoplasm. Importantly, cytoplasmic glycolysis is associated with an increase in a protein called glucose transporter 1 (Glut 1). 17beta estradiol (E2) can ameliorate experimental PH, but its effects on RV glut 1 expression are not yet known. The aim of this project is to determine the RV expression of Glut 1 in a rat model of severe PH, and to investigate whether this is decreased by E2 treatment. We assessed Glut 1 via immunofluorescence staining in cryosections of RV tissue from control rats, untreated PH rats, and E2-treated PH rats. Cell nuclei were stained with DAPI (Diamidinophenyl-indole), cell membranes were stained with WGA (wheat germ agglutinin), and Glut1 was stained with a Glut1 antibody conjugated to a red immunofluorescent dye. Nuclei are stained blue; cell membranes are stained green. Glut 1 quantification occurs via visual inspection and determination of red staining via specific software (Metamorph). We were able to successfully establish the protocol for Glut1 staining. In pilot experiments, there was little Glut1 staining present in normal RVs, but we detected up-regulation of Glut 1 in the RV of animals with PH. Whether this is affected by E2 is currently under investigation

    Microsatellite primers for two threatened orchids in Florida: Encyclia tampensis and Cyrtopodium punctatum (Orchidaceae)1

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    Premise of the study: The Million Orchid Project at Fairchild Tropical Botanic Garden is an initiative to propagate native orchids for reintroduction into Miami?s urban landscapes. The aim of this study was to develop microsatellites for Encyclia tampensis and Cyrtopodium punctatum (Orchidaceae). Methods and Results: Ten microsatellites were developed for each species. For E. tampensis sampled from the natural population, allele numbers ranged from one to four, with an average observed heterozygosity (Ho) of 0.314 and average expected heterozygosity (He) of 0.281. For the individuals from cultivation, allele numbers ranged from one to six, with an average Ho of 0.35 and an average He of 0.224. For C. punctatum, allele numbers ranged from one to three, with an average Ho of 0.257 and an average He of 0.272. Conclusions: These microsatellites will be used to assess the genetic diversity of natural and cultivated populations with the intention of guiding genetic breeding under the Million Orchid Project

    High toxicity and specificity of the saponin 3-GlcA-28-AraRhaxyl-medicagenate, from Medicago truncatula seeds, for Sitophilus oryzae

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    <p>Abstract</p> <p>Background</p> <p>Because of the increasingly concern of consumers and public policy about problems for environment and for public health due to chemical pesticides, the search for molecules more safe is currently of great importance. Particularly, plants are able to fight the pathogens as insects, bacteria or fungi; so that plants could represent a valuable source of new molecules.</p> <p>Results</p> <p>It was observed that <it>Medicago truncatul</it>a seed flour displayed a strong toxic activity towards the adults of the rice weevil <it>Sitophilus oryzae</it> (Coleoptera), a major pest of stored cereals. The molecule responsible for toxicity was purified, by solvent extraction and HPLC, and identified as a saponin, namely 3-GlcA-28-AraRhaxyl-medicagenate. Saponins are detergents, and the CMC of this molecule was found to be 0.65 mg per mL. Neither the worm <it>Caenorhabditis elegans</it> nor the bacteria <it>E. coli</it> were found to be sensitive to this saponin, but growth of the yeast <it>Saccharomyces cerevisiae</it> was inhibited at concentrations higher than 100 μg per mL. The purified molecule is toxic for the adults of the rice weevils at concentrations down to 100 μg per g of food, but this does not apply to the others insects tested, including the coleopteran <it>Tribolium castaneum</it> and the Sf9 insect cultured cells.</p> <p>Conclusions</p> <p>This specificity for the weevil led us to investigate this saponin potential for pest control and to propose the hypothesis that this saponin has a specific mode of action, rather than acting <it>via</it> its non-specific detergent properties.</p

    An analysis of baseline data from the PROUD study: an open-label randomised trial of pre-exposure prophylaxis

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    Background: Pre-exposure prophylaxis (PrEP) has proven biological efficacy to reduce the sexual acquisition of the human immunodeficiency virus (HIV). The PROUD study found that PrEP conferred higher protection than in placebo-controlled trials, reducing HIV incidence by 86 % in a population with seven-fold higher HIV incidence than expected. We present the baseline characteristics of the PROUD study population and place the findings in the context of national sexual health clinic data. Methods: The PROUD study was designed to explore the real-world effectiveness of PrEP (tenofovir-emtricitabine) by randomising HIV-negative gay and other men who have sex with men (GMSM) to receive open-label PrEP immediately or after a deferral period of 12 months. At enrolment, participants self-completed two baseline questionnaires collecting information on demographics, sexual behaviour and lifestyle in the last 30 and 90 days. These data were compared to data from HIV-negative GMSM attending sexual health clinics in 2013, collated by Public Health England using the genitourinary medicine clinic activity database (GUMCAD). Results: The median age of participants was 35 (IQR: 29–43). Typically participants were white (81 %), educated at a university level (61 %) and in full-time employment (72 %). Of all participants, 217 (40 %) were born outside the UK. A sexually transmitted infection (STI) was reported to have been diagnosed in the previous 12 months in 330/515 (64 %) and 473/544 (87 %) participants reported ever having being diagnosed with an STI. At enrolment, 47/280 (17 %) participants were diagnosed with an STI. Participants reported a median (IQR) of 10 (5–20) partners in the last 90 days, a median (IQR) of 2 (1–5) were condomless sex acts where the participant was receptive and 2 (1–6) were condomless where the participant was insertive. Post-exposure prophylaxis had been prescribed to 184 (34 %) participants in the past 12 months. The number of STI diagnoses was high compared to those reported in GUMCAD attendees. Conclusions: The PROUD study population are at substantially higher risk of acquiring HIV infection sexually than the overall population of GMSM attending sexual health clinics in England. These findings contribute to explaining the extraordinary HIV incidence rate during follow-up and demonstrate that, despite broad eligibility criteria, the population interested in PrEP was highly selective. Trial registration: Current Controlled TrialsISRCTN94465371. Date of registration: 28 February 2013

    Pre-exposure prophylaxis to prevent the acquisition of HIV-1 infection (PROUD) : effectiveness results from the pilot phase of a pragmatic open-label randomised trial

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    Background Randomised placebo-controlled trials have shown that daily oral pre-exposure prophylaxis (PrEP) with tenofovir-emtricitabine reduces the risk of HIV infection. However, this benefit could be counteracted by risk compensation in users of PrEP. We did the PROUD study to assess this effect. Methods PROUD is an open-label randomised trial done at 13 sexual health clinics in England. We enrolled HIV-negative gay and other men who have sex with men who had had anal intercourse without a condom in the previous 90 days. Participants were randomly assigned (1:1) to receive daily combined tenofovir disoproxil fumarate (245 mg) and emtricitabine (200 mg) either immediately or after a deferral period of 1 year. Randomisation was done via web-based access to a central computer-generated list with variable block sizes (stratified by clinical site). Follow-up was quarterly. The primary outcomes for the pilot phase were time to accrue 500 participants and retention; secondary outcomes included incident HIV infection during the deferral period, safety, adherence, and risk compensation. The trial is registered with ISRCTN (number ISRCTN94465371) and ClinicalTrials.gov (NCT02065986). Findings We enrolled 544 participants (275 in the immediate group, 269 in the deferred group) between Nov 29, 2012, and April 30, 2014. Based on early evidence of effectiveness, the trial steering committee recommended on Oct 13, 2014, that all deferred participants be offered PrEP. Follow-up for HIV incidence was complete for 243 (94%) of 259 patient-years in the immediate group versus 222 (90%) of 245 patient-years in the deferred group. Three HIV infections occurred in the immediate group (1·2/100 person-years) versus 20 in the deferred group (9·0/100 person-years) despite 174 prescriptions of post-exposure prophylaxis in the deferred group (relative reduction 86%, 90% CI 64-96, p=0·0001; absolute difference 7·8/100 person-years, 90% CI 4·3-11·3). 13 men (90% CI 9-23) in a similar population would need access to 1 year of PrEP to avert one HIV infection. We recorded no serious adverse drug reactions; 28 adverse events, most commonly nausea, headache, and arthralgia, resulted in interruption of PrEp. We detected no difference in the occurrence of sexually transmitted infections, including rectal gonorrhoea and chlamydia, between groups, despite a suggestion of risk compensation among some PrEP recipients. Interpretation In this high incidence population, daily tenofovir-emtricitabine conferred even higher protection against HIV than in placebo-controlled trials, refuting concerns that effectiveness would be less in a real-world setting. There was no evidence of an increase in other sexually transmitted infections. Our findings strongly support the addition of PrEP to the standard of prevention for men who have sex with men at risk of HIV infection. Funding MRC Clinical Trials Unit at UCL, Public Health England, and Gilead Sciences

    A chemical survey of exoplanets with ARIEL

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    Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 μm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio

    Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

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    Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

    Burn injury leads to increased long-term susceptibility to respiratory infection in both mouse models and population studies

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    Background: Burn injury initiates an acute inflammatory response that subsequently drives wound repair. However, acute disruption to the immune response is also common, leading to susceptibility to sepsis and increased morbidity and mortality. Despite increased understanding of the impact of burn injury on the immune system in the acute phase, little is known about longterm consequences of burn injury on immune function. This study was established to determine whether burn injury has long-term clinical impacts on patients' immune responses. Methods: Using a population-based retrospective longitudinal study and linked hospital morbidity and death data from Western Australia, comparative rates of hospitalisation for respiratory infections in burn patients and a non-injured comparator cohort were assessed. In addition, a mouse model of non-severe burn injury was also used in which viral respiratory infection was induced at 4 weeks post-injury using a mouse modified version of the Influenza A virus (H3NN; A/mem/71-a). Results and conclusions: The burn injured cohort contained 14893 adult patients from 1980-2012 after removal of those patients with evidence of smoke inhalation or injury to the respiratory tract. During the study follow-up study a total of 2,884 and 2,625 respiratory infection hospital admissions for the burn and uninjured cohorts, respectively, were identified. After adjusting for covariates, the burn cohort experienced significantly elevated admission rates for influenza and viral pneumonia (IRR, 95%CI: 1.73, 1.27-2.36), bacterial pneumonia (IRR, 95%CI: 2.05, 1.85-2.27) and for other types of upper and lower respiratory infections (IRR, 95% CI: 2.38, 2.09-2.71). In the mouse study an increased viral titre was observed after burn injury, accompanied by a reduced CD8 response and increased NK and NKT cells in the draining lymph nodes. This data suggests burn patients are at long-term increased risk of infection due to sustained modulation of the immune response
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