1,676 research outputs found

    Narratives as a mode of research evaluation in citizen science: understanding broader science communication impacts

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    Science communicators develop qualitative and quantitative tools to evaluate the ‘impact’ of their work however narrative is rarely adopted as a form of evaluation. We posit narrative as an evaluative approach for research projects with a core science communication element and offer several narrative methods to be trialled. We use citizen science projects as an example of science communication research seeking to gain knowledge of participant-emergent themes via evaluations. Storied experience of participant involvement enhances understanding of context-based and often intangible processes, such as changing place-relations, values, and self-efficacy, by enabling a reflective space for critical-thinking and self-reflection

    Impact de la variation du niveau d'eau d'un marais du lac Saint-Pierre (Québec, Canada) sur les concentrations et les flux d'hydrogÚne, monoxyde de carbone, méthane et dioxyde de carbone

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    Le but de la présente étude était d'étudier l'impact de la variation des niveaux d'eau d'un marais d'eau douce (Baie Saint-François, Québec) sur l'évolution des concentrations et des flux d'hydrogÚne, monoxyde de carbone, méthane et dioxyde de carbone. Une approche originale impliquant l'association d'un gradient de concentration de ces composés sur un profil vertical de 1,5 m au transfert de flux turbulent micrométéorologique fut utilisée pour la détermination des flux. L'étude démontre qu'une hausse du niveau d'eau d'un bassin versant alimentant une zone humide influence les flux de méthane, de monoxyde de carbone d'hydrogÚne et de dioxyde de carbone. En conditions submergées, le marais émettait du méthane et du monoxyde de carbone et consommait moins d'hydrogÚne troposphérique. Ainsi, cette étude démontre que des mesures in situ peuvent servir à inférer des scénarios d'impacts possibles des changements climatiques et des variations des niveaux d'eau sur les émissions des gaz à effets de serre dans l'écosystÚme du fleuve Saint-Laurent.Wetlands are known for their great biodiversity and the important carbon reservoir that they represent. Moreover, in the global warming context, these ecosystems represent net sources or sinks for different greenhouse gases depending of their conditions. For instance, flooded conditions favour methane production whereas they prevent hydrogen and carbon monoxide soil consumption. Baie Saint-François is a freshwater wetland that opens onto Lake Saint-Pierre (St. Lawrence River) where water levels are subject to important fluctuations due to natural processes and human activities (hydroelectricity and navigation). This study was done in order to assess the impact of the Lake Saint-Pierre water level variations on the tropospheric methane, carbon monoxide, hydrogen and carbon dioxide dynamics over the wetland. Knowledge of these dynamics should provide indications about the possible effects of the decreasing or increasing water level associated with the global warming on the production or consumption of these trace gases.Studies were carried out between June and August 2003 in Baie Saint-François where soil was subjected to successions of flooded and dry conditions. Water and carbon dioxide fluxes were obtained with a Bowen ratio micrometeorological station including a high frequency single infrared gas analyser. Hydrogen, carbon monoxide and methane fluxes were estimated with the modified Bowen method, their vertical concentration gradients (1.5 m) were measured over the plant canopy. The Bowen Ratio station was equipped with different probes to measure parameters such as net radiations, soil heat fluxes and vertical temperature gradients. The turbulent transfer coefficient (k) obtained every 20 min was assumed equal for heat, water vapour and trace gases. Hence, fluxes calculations were done by the multiplication of the turbulent transfer coefficients with the vertical concentration gradients of hydrogen, carbon monoxide and methane.The instrument used to detect hydrogen, carbon monoxide and methane was a RGA5. This analyser has two detectors: the reductive gas detector (RGD) for hydrogen and carbon monoxide and a flame ionisation detector (FID) for methane. The RGD contains an HgO bed wherein oxygen reacts with reductive gases resulting in Hg° releases detectable by differential UV absorbance. Chemicals were detected continuously in 10 min cycles with an analytical reproducibility of ±0.2, 0.3 and 2% for hydrogen, carbon monoxide and methane. Generally, vertical concentration gradients measured were greater than these limits. A calibration gas containing hydrogen, carbon monoxide and methane at 4940, 1000 and 1000 ppbv respectively in nitrogen was analysed daily to verify calibration. To ensure data integrity, linearity of the instrument was assayed by several dilutions of the standard gas and the integration of the curves gave a correction factor for hydrogen (18%) and carbon monoxide (13%). An intercomparison with NOAA (National Oceanic and Atmospheric Administration) was done to corroborate these correction factors.Background carbon monoxide, methane and carbon dioxide levels were in agreement with literature values. However, hydrogen was low, as observed by other investigators in summertime, since this season is related to minimal concentrations. Methane followed a diurnal cycle where maximum levels were observed during nighttime. In wet conditions, these nocturnal peaks reached occasionally 4000 ppbv and could be explained by specific production mechanisms and diurnal changes of vertical mixing in the boundary layer. Sensitivity of the processes responsible for methane and carbon monoxide cycling was seen between July 21st and 26th where a rain episode (total precipitation of 33.2 mm) increased their background concentrations. It seems that this precipitation was enough to favour methanogenesis and inhibit tropospheric CO and CH4 consumptions by a reduction of the diffusion of these chemicals into the soil.Our results demonstrated that four to eleven days following a variation of the Lake Saint-Pierre water level, a change in the tropospheric hydrogen, carbon monoxide and methane concentrations was observed. This lag might be explained by the distance between the lake and the research station (about 1.5 km) and the required time for the adaptation of soil microorganisms to the disruption of their environment. The concentration variations of these chemicals resulted from the inhibition of the processes responsible for their consumption or the activation of the processes accountable for their production.In June, the wetland was flooded and the CO2 median flux was -56.5 g m-2 d-1. Fluxes increased significantly (Mann-Whitney, α=0.01) in July to 5.30 g m-2 d-1, possibly due to dry conditions. Indeed, absence of water favours the activity of soil aerobic microorganisms which might produce more carbon dioxide than the quantity used by plants during photosynthesis.Methane was produced in June where the median flux was 54 mg m-2 d-1. These emissions were caused by the presence of water which maintained anaerobic conditions in the sediments, a suitable environment for methanogenic microorganisms. July was characterised by dry conditions, which generated aerobic environments in soils, an unfavourable microniche for methanogens. Therefore, methane median fluxes decreased significantly (Mann-Whitney, α=0.05) to 0.011 mg m-2 d-1 in July. In August, before the end of the investigation period, water levels had increased but methane fluxes were not significantly higher than in July. Moreover, in this period, methane concentrations tended to increase, showing that after an augmentation of the Lake Saint-Pierre water level, Baie Saint-François flooding area could represent a methane source.During summer 2003, Baie Saint-François acted as a net source of carbon monoxide. In June, the median flux was 21 ”g m-2 d-1 due to presence of water which inhibited consumption by soil. Emissions were significantly (Mann-Whitney, α=0.05) lower in July (15 ”g m-2 d-1) due to the absence of water, which represented a suitable environment for microorganisms consuming tropospheric carbon monoxide. In August, the median carbon monoxide flux attained 65 ”g m-2 d-1 due to an increase of the Lake Saint-Pierre water level. Net carbon monoxide emissions observed in wet and dry conditions might be due to the high organic content in soil and water in addition to the presence of plants since all of these are subjected to photooxidation, generating this pollutant. Therefore, an increase of the Lake Saint-Pierre water level is associated with an augmentation of tropospheric carbon monoxide due to the inhibition of the processes responsible of its consumption.A decline in the water level might result in the activation of the soil microorganisms (or abiotic hydrogenases) able to consume tropospheric hydrogen. At the beginning of the campaign (June), the median hydrogen flux was weak (-1.37 g m-2 d-1) due to the presence of water. However, a net soil consumption was seen in July, where the median hydrogen flux decreased to -125 g m-2 d-1. The Lake Saint-Pierre water level increase observed in August was associated with a significant (Mann-Whitney, α=0.05) augmentation of the hydrogen median flux to 299 g m-2 d-1. Consequently, a rise in the Lake Saint-Pierre water levels induced an inhibition of the processes responsible of the tropospheric hydrogen consumption.This study illustrated that the water level fluctuations of the Lake Saint-Pierre have an impact on the H2, CO, CH4 and CO2 dynamics over the surrounding wetlands. When the Lake Saint-Pierre water level decreased, the wetlands acted as a carbon monoxide and carbon dioxide source, but as a consumer of tropospheric hydrogen and a minor source of methane

    A high resolution electron energy loss spectroscopy study of the Fermi resonance of CO<sub>2</sub> adsorbed on a Ag(110)/CO<sub>3</sub> layer

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    The adsorption of CO2 on a Ag(110) surface precovered with a saturated CO3 layer has been studied by high resolution electron energy loss spectroscopy (HREELS). A weakly bound state of CO2 is stabilized by the presence of carbonate. In addition to the losses of the bend (658 cm−1) and the antisymmetric stretch (2343 cm−1) fundamental modes, the presence of two peaks in the frequency region of the symmetric stretch mode have been observed. Such a loss pair is characteristic for the existence of a Fermi resonance, between the overtone of the bend and the symmetric stretch vibration, which had been studied in detail for the gas phase CO2 molecule. By use of three CO2 isotopomers the existence of the Fermi resonance in the adsorbed state has been verified and the Fermi constant and the energy of the unperturbed vibrations have been determined from the isotopic shifts. The character of the CO2 molecule is almost unaffected by the bonding and it adsorbs in a tilted geometry

    Exploring the experience of acute inpatient mental health care from the perspective of family and carers of people experiencing psychosis: A qualitative thematic analysis study conducted during the COVID-19 pandemic

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    Family and carers play an important role in supporting service users who are in receipt of acute mental health inpatient care, but they can also be significantly emotionally and physically impacted. The aim of this study was to examine their needs and priorities during this time. Fourteen family and carers of inpatients experiencing psychosis completed semi-structured interviews examining their experiences of inpatient care during the COVID-19 pandemic. Thematic analysis was used to analyse data. Four key themes were identified: ‘A turbulent journey to hospital admission’, ‘I need information and support’, ‘Maintaining my relationship with my loved one’ and ‘Inpatient care is a mixed bag’. Each theme comprised four or five subthemes. The findings demonstrated that family and carers feel excluded from inpatient care and struggled to maintain contact with their loved ones, which was exacerbated by COVID-19 related restrictions. Communication and being regularly informed about their loved one’s care, as well as visiting loved ones, was particularly problematic. Inpatient care needs to be more inclusive of family and carers and ensure they are kept in mind at every stage of the admission

    The neural stem cell microenvironment

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    In mammals, neural stem cells appear early in development and remain active within the central nervous system for the whole life duration of the organism. During this developmental process they assume different cellular morphologies and reside within changing microenvironments whilst retaining the basic properties of a stem cell: multipotentiality and the ability to self renew. In this chapter, the basic morphological characteristics of neural stem cells will be reviewed, along with the fundamental structural components and signalling molecules of their microenvironments. In early neural development, when the patterning of the nervous system is established, neural stem cells are called neuroepithelial cells; they are situated among other neuroepithelial cells and they are exposed to various signals such as retinoic acid, sonic hedgehog and fibroblast growth factors. When neurogenesis commences, stem cells are transformed to radial glial cells and the complexity of their microenvironment increases due to the emergence of various types of neuronal progenitors, differentiated cells and extracellular signaling molecules. Finally, during adulthood, neural stem cells assume astroglial morphology and reside in specific microenvironments that are called neurogenic niches; small neurogenic islands where neurons and glia are continuously generated under the control of mechanisms largely similar to those operating during embryonic development

    Improving School Leadership: The Promise of Cohesive Leadership Systems

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    Describes Wallace grantees' work to create a cohesive leadership system of coordinated policies between states and districts and across state agencies, states' and districts' efforts to forge cohesive policies, and the impact on instructional leadership

    ESSAYS ON INTERNATIONAL INVESTMENT TREATIES, INVESTOR-STATE DISPUTES AND DOUBLE TAX TREATIES

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    Chapter 1 explores the effects of international investment treaties on institutional quality. Capital importing countries use bilateral investment treaties (BITs) as a means to attract foreign investors who see these investment agreements as an effective tool to employ in case of an investment dispute. Several countries, often at the expense of their sovereign rights, have engaged in unbridled foreign capital competition, which has resulted in a massive proliferation of BITs since the 1990s. This chapter contributes to the debate over whether BITs harm the institutional quality (IQ) of signatory countries due to the possibility established by BITs of resorting to international jurisdictions to settle potential investment disputes. Using a panel of data from 132 countries over the period 1984–2012, this study suggests that BITs have no significant effects on IQ. However, the results reveal a significant positive effect of BITs on the IQ of Southern countries. While BITs do not significantly affect some IQ components such as corruption, law and order, quality of bureaucracy, government stability, and investment profile, I find that BITs have a positive and significant effect on the socioeconomic conditions of Southern countries. Specifically, I find that South-North BITs have a significant and positive effect on socioeconomic conditions in host countries. In contrast, I find no significant effects of South-South BITs on IQ. I conclude that South-North rather than South-South investment cooperation BITs are beneficial to Southern countries, by improving their socioeconomic conditions. Chapter 2 investigates some new determinants of investor-state disputes. In recent years, there has been a proliferation of disputes claims brought against investment host states by foreign investors, at the International Center for Settlement of Investment Disputes (ICSID). This trend seems to be a natural consequence of the growing number of bilateral investment treaties (BITs) signed since the 1990s. This chapter seeks to further investigate the determinants of investor-state disputes by adding to existing analyses of claimants’ home state characteristics and exploring other factors such as trade agreements and export partners that could potentially influence the incidence of disputes. The research herein provides strong evidence that weak institutions and the stock of FDI inflows into host states are key factors in explaining investor-state disputes. Also, BITs are not the only pass-throughs of investment disputes. I found that trade agreements are also determinant factors of investor-states disputes due to the investment protection provisions embedded in these agreements. Also, lingering colonial ties that allow for greater economic exchange between former colonial powers and their former colonies constitute a channel for investment disputes. These findings confirm that institutional quality still matters and suggest that developing countries that are primarily capital-importing countries via the signing of investment treaties could avoid unnecessary depletion of their scarce resources into international arbitration if they invest in improving their institutions. Chapter 3 analyses the effects of double tax treaties on tax revenues. The recent surge of cross border investments has raised awareness on the question of double taxation, making policies on profits taxation of Multinational Corporation more than ever relevant. Governments in many countries rely heavily on tax revenues for different purposes such as provision of infrastructures, functioning of public administration and other social services. Double tax treaties negotiated between two sovereign states aim to reduce or eliminate the burden of double taxation on the same taxpayer and for the same subject matter. The literature on double tax treaties generally suggests that double tax treaties might be harmful to treaty partners especially when there is an asymmetry between countries in terms of flows of foreign direct investment. This chapter examines the effects of Double Taxation Treaties on Tax Revenues using a panel data of 37 countries over the period 1990-2010. Using fixed effect and system GMM methods, the results show a bell shape relationship between tax revenue and tax treaties. The findings suggest that countries signing tax treaties should expect at least two effects: a positive effect of tax treaties on tax revenues in the short run followed by a diminishing effect in the long run

    Pharmacokinetics, safety, and efficacy of a single co-administered dose of diethylcarbamazine, albendazole and ivermectin in adults with and without Wuchereria bancrofti infection in Cote d\u27Ivoire

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    BackgroundA single co-administered dose of ivermectin (IVM) plus diethylcarbamazine (DEC) plus albendazole (ALB), or triple-drug therapy, was recently found to be more effective for clearing microfilariae (Mf) than standard DEC plus ALB currently used for mass drug administration programs for lymphatic filariasis (LF) outside of sub-Saharan Africa. Triple-drug therapy has not been previously tested in LF-uninfected individuals from Africa. This study evaluated the pharmacokinetics (PK), safety, and efficacy of triple-drug therapy in people with and without Wuchereria bancrofti infection in West Africa.MethodsIn this open-label cohort study, treatment-naïve microfilaremic (>50 mf/mL, n = 32) and uninfected (circulating filarial antigen negative, n = 24) adults residing in Agboville district, Cîte d’Ivoire, were treated with a single dose of IVM plus DEC plus ALB, and evaluated for adverse events (AEs) until 7 days post treatment. Drug levels were assessed by liquid chromatography and mass spectrometry. Persons responsible for assessing AEs were blinded to participants’ infection status.FindingsThere was no difference in AUC0-inf or Cmax between LF-infected and uninfected participants (P>0.05 for all comparisons). All subjects experienced mild AEs; 28% and 25% of infected and uninfected participants experienced grade 2 AEs, respectively. There were no severe or serious adverse events. Only fever (16 of 32 versus 4 of 24, PConclusionsModerate to heavy W. bancrofti infection did not affect PK parameters for IVM, DEC or ALB following a single co-administered dose of these drugs compared to uninfected individuals. The drugs were well tolerated. This study confirmed the efficacy of the triple-drug therapy for clearing W. bancrofti Mf and has added important information to support the use of this regimen in LF elimination programs in areas of Africa without co-endemic onchocerciasis or loiasis.Trial registrationClinicalTrials.gov NCT02845713.</div
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