361 research outputs found

    2,4-D and Glyphosate affect aquatic biofilm accrual, gross primary production, and community respiration

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    This activity involved the presentation of a poster titled “2,4-D and Glyphosate affect aquatic biofilm accrual, gross primary production, and community respiration”, at the 2013 conference of the Society for Freshwater Sciences. The research that was presented was significant because it was the first report of how common herbicides 2,4-D and glyphosate affect algal biofilms that grow on surfaces in freshwater ecosystems.2,4-Dichlorophenoxyacetic acid (2,4-D) and glyphosate are widely used agricultural herbicides commonly found in surface waters near cultivated land. Field experiments were conducted to determine the effects of 2,4-D and glyphosate on biofilms in a pond next to agricultural land in Athabasca, Alberta. Diffusing substrates consisted of specimen jars filled with agar that contained low levels of nitrogen and phosphorus, and different concentrations (15, 9.0, 1.5 mM) of either 2,4-D or glyphosate. A circular hole in the lid of the jar was covered with either a GF/C glass fiber or a cellulose filter paper which functioned as the biofilm substrate. Nutrients and herbicide diffused freely through the agar to the substrate surface. Arrays of diffusing substrates were suspended 15 cm below the water surface for 22 days, after which O2 production and consumption were measured to give the rates of primary production and respiration. Biomass was measured as Chl-a. 2,4-D and glyphosate caused significant decreases in rates of biomass accrual, primary production, and respiration. For both compounds, dose responses were highest at the highest concentrations

    Student and Faculty Outcomes of Undergraduate Science Research Projects by Geographically Dispersed Students

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    Senior undergraduate research projects are important components of most undergraduate science degrees. The delivery of such projects in a distance education format is challenging. Athabasca University (AU) science project courses allow distance education students to complete research project courses by working with research supervisors in their local area, coordinated at a distance by AU faculty. This paper presents demographics and course performance for 155 students over five years. Pass rates were similar to other distance education courses. Research students were surveyed by questionnaire, and external supervisors and AU faculty were interviewed, to examine the outcomes of these project courses for each group. Students reported high levels of satisfaction with the course, local supervisors, and faculty coordinators. Students also reported that the experience increased their interest in research, and the probability that they would pursue graduate or additional certification. Local supervisors and faculty affirmed that the purposes of project courses are to introduce the student to research, provide opportunity for students to use their cumulative knowledge, develop cognitive abilities, and independent thinking. The advantages and challenges associated with this course model are discussed

    The futile search for ‘physiological evidence’ of male bisexuality: a response to Jabbour et al. (2020)

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    “Robust evidence for bisexual orientation among men” (Jabbour et al., 2020) collates data from eight studies measuring the genital responses of bisexual-identified cisgender men to erotic stimuli. The goal of the article is to provide “empirical verification [of male bisexuality through] physiological processes rather than self-report.” (Jabbour et al., 2020, p. 1). Two questions emerge from this publication. First, is such research necessary? Second, can one physiologically ‘prove’ a sexuality’s existence using the penile plethysmograph (phallometry)? This paper will first discuss some of the scientific inaccuracies and methodological flaws with Jabbour et al. (2020), followed by a critical reflection on the social import of these studies in relation to the medicalisation of sexuality

    Identifying positively deviant elderly medical wards using routinely collected NHS Safety Thermometer data: an observational study.

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    Objective The positive deviance approach seeks to identify and learn from exceptional performers. Although a framework exists to apply positive deviance within healthcare organisations, there is limited guidance to support its implementation. The approach has also rarely explored exceptional performance on broad outcomes, been implemented at ward level, or applied within the UK. This study develops and critically appraises a pragmatic method for identifying positively deviant wards using a routinely collected, broad measure of patient safety. Design A two-phased observational study was conducted. During phase 1, cross-sectional and temporal analyses of Safety Thermometer data were conducted to identify a discrete group of positively deviant wards that consistently demonstrated exceptional levels of safety. A group of matched comparison wards with above average performances were also identified. During phase 2, multidisciplinary staff and patients on the positively deviant and comparison wards completed surveys to explore whether their perceptions of safety supported the identification of positively deviant wards. Setting 34 elderly medical wards within a northern region of England, UK. Participants Multidisciplinary staff (n=161) and patients (n=188) clustered within nine positively deviant and comparison wards. Results Phase 1: A combination of analyses identified five positively deviant wards that performed best in the region, outperformed their organisation and performed consistently well over 12 months. Five above average matched comparator wards were also identified. Phase 2: Staff and patient perceptions of safety generally supported the identification of positively deviant wards using Safety Thermometer data, although patient perceptions of safety were less concordant with the routinely collected data. Conclusions This study tentatively supports a pragmatic method of using routinely collected data to identify positively deviant elderly medical wards; however, it also highlights the various challenges that are faced when conducting the first stage of the positive deviance approach. Trial registration number UK Clinical Research Network Portfolio (reference-18050)

    Quenched Cold Accretion of a Large Scale Metal-Poor Filament due to Virial Shocking in the Halo of a Massive z=0.7 Galaxy

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    Using HST/COS/STIS and HIRES/Keck high-resolution spectra, we have studied a remarkable HI absorbing complex at z=0.672 toward the quasar Q1317+277. The HI absorption has a velocity spread of 1600 km/s, comprises 21 Voigt profile components, and resides at an impact parameter of D=58 kpc from a bright, high mass [log(M_vir/M_sun) ~ 13.7] elliptical galaxy that is deduced to have a 6 Gyr old, solar metallicity stellar population. Ionization models suggest the majority of the structure is cold gas surrounding a shock heated cloud that is kinematically adjacent to a multi-phase group of clouds with detected CIII, CIV and OVI absorption, suggestive of a conductive interface near the shock. The deduced metallicities are consistent with the moderate in situ enrichment relative to the levels observed in the z ~ 3 Ly-alpha forest. We interpret the HI complex as a metal-poor filamentary structure being shock heated as it accretes into the halo of the galaxy. The data support the scenario of an early formation period (z > 4) in which the galaxy was presumably fed by cold-mode gas accretion that was later quenched via virial shocking by the hot halo such that, by intermediate redshift, the cold filamentary accreting gas is continuing to be disrupted by shock heating. Thus, continued filamentary accretion is being mixed into the hot halo, indicating that the star formation of the galaxy will likely remain quenched. To date, the galaxy and the HI absorption complex provide some of the most compelling observational data supporting the theoretical picture in which accretion is virial shocked in the hot coronal halos of high mass galaxies.Comment: 20 pages, 9 figures, submitted to Ap

    Failing boys and moral panics: perspectives on the underachievement debate

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    The paper re-examines the underachievement debate from the perspective of the ‘discourse of derision’ that surrounds much writing in this area. It considers the contradictions and inconsistencies which underpin much of the discourse – from a reinterpretation of examination scores, to the conflation of the concepts of ‘under’ and ‘low’ achievement and finally to the lack of consensus on a means of defining and measuring the term underachievement. In doing so, this paper suggests a more innovative approach for understanding, re-evaluating and perhaps rejecting the notion of underachievement

    Red squirrels in the British Isles are infected with leprosy bacilli

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    Leprosy, caused by infection with Mycobacterium leprae or the recently discovered Mycobacterium lepromatosis, was once endemic in humans in the British Isles. Red squirrels in Great Britain (Sciurus vulgaris) have increasingly been observed with leprosy-like lesions on the head and limbs. Using genomics, histopathology, and serology, we found M. lepromatosis in squirrels from England, Ireland, and Scotland, and M. leprae in squirrels from Brownsea Island, England. Infection was detected in overtly diseased and seemingly healthy animals. Phylogenetic comparisons of British and Irish M. lepromatosis with two Mexican strains from humans show that they diverged from a common ancestor around 27,000 years ago, whereas the M. leprae strain is closest to one that circulated in Medieval England. Red squirrels are thus a reservoir for leprosy in the British Isles

    Improving Patients' Adherence to Physical Activity in Diabetes Mellitus: A Review

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    Regular physical activity (PA) is a key element in the prevention and management of type 2 diabetes mellitus (T2DM). Participation in regular PA improves blood glucose control and can prevent or delay T2DM and its complications, along with positively affecting lipids, blood pressure, cardiovascular events, mortality, and quality of life. However, most people with T2DM are not active and show poor adherence. This paper reviews the possible barriers to PA and strategies to improve the adherence to PA. Based on the currently available literature, it is concluded that self-efficacy and social support from family, friends, and health care providers play the important role in adoption and maintenance of regular PA. Here we also highlight some new modern and innovative interventions that facilitate exercise participation and improve the adherence
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