137 research outputs found

    Extraction of ellagitannins from oak wood of model casks

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    Eight experimental model casks were constructed using wood from four oak trees and filled with a 12 % ethanol solution for 200 days. The concentration of ellagitannins was subsequently measured in the solutions and in the inner and outer faces of the cask wood. Only a low proportion of the total ellagitannins was extracted from the wood, and this proportion varied significantly between both different casks and between the eight ellagitannins measured. The two most abundant ellagitannins, castalagin and vescalagin, were the least easily extracted. The concentration of ellagitannins was much lower in the solutions than expected from calculations based on the difference between the inner and outer faces of the wood. This degradation of ellagitannins occurs subsequent to their extraction into solution

    Candidate Risk Factors and Mechanisms for Tolvaptan-Induced Liver Injury Are Identified Using a Collaborative Cross Approach

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    Clinical trials of tolvaptan showed it to be a promising candidate for the treatment of Autosomal Dominant Polycystic Kidney Disease (ADPKD) but also revealed potential for idiosyncratic drug-induced liver injury (DILI) in this patient population. To identify risk factors and mechanisms underlying tolvaptan DILI, 8 mice in each of 45 strains of the genetically diverse Collaborative Cross (CC) mouse population were treated with a single oral dose of either tolvaptan or vehicle. Significant elevations in plasma alanine aminotransferase (ALT) were observed in tolvaptan-treated animals in 3 of the 45 strains. Genetic mapping coupled with transcriptomic analysis in the liver was used to identify several candidate susceptibility genes including epoxide hydrolase 2, interferon regulatory factor 3, and mitochondrial fission factor. Gene pathway analysis revealed that oxidative stress and immune response pathways were activated in response to tolvaptan treatment across all strains, but genes involved in regulation of bile acid homeostasis were most associated with tolvaptan-induced elevations in ALT. Secretory leukocyte peptidase inhibitor (Slpi) mRNA was also induced in the susceptible strains and was associated with increased plasma levels of Slpi protein, suggesting a potential serum marker for DILI susceptibility. In summary, tolvaptan induced signs of oxidative stress, mitochondrial dysfunction, and innate immune response in all strains, but variation in bile acid homeostasis was most associated with susceptibility to the liver response. This CC study has indicated potential mechanisms underlying tolvaptan DILI and biomarkers of susceptibility that may be useful in managing the risk of DILI in ADPKD patients

    Divided we stand: institutional collaboration in tourism planning and development in the Central Region of Ghana

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    This research is an exploratory study that examines collaboration at the institutional level in the tourism sector of the Central Region, Ghana. The research begins with a review of the key issues related to collaboration in tourism planning and development followed by an extensive exploration of three main issues related to institutional collaboration in tourism in the Central Region. The three main issues are the vision of tourism development shared among stakeholders, collaboration and coordination within the public sector and between the public and private sectors and the factors that constrain and facilitate collaboration and coordination. Using extensive interviews with key stakeholders and reviewing policy documents, the research indicates low levels of collaboration between tourism institutions both within the public sector and across the public?private sectors. This is notwithstanding a shared awareness of the benefits of collaboration among all actors. The research thus contributes interesting insights into the politics of collaboration in tourism destinations. Given tourism's contribution to the Ghanaian economy, it is imperative that efforts are made towards improving the levels of collaboration and coordination between tourism agencies and institutions

    Climatic predictors of species distributions neglect biophysiologically meaningful variables

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    This is the final version. Available on open access from Wiley via the DOI in this record.Aim: Species distribution models (SDMs) have played a pivotal role in predicting how species might respond to climate change. To generate reliable and realistic predictions from these models requires the use of climate variables that adequately capture physiological responses of species to climate and therefore provide a proximal link between climate and their distributions. Here, we examine whether the climate variables used in plant SDMs are different from those known to influence directly plant physiology. Location: Global. Methods: We carry out an extensive, systematic review of the climate variables used to model the distributions of plant species and provide comparison to the climate variables identified as important in the plant physiology literature. We calculate the top ten SDM and physiology variables at 2.5 degree spatial resolution for the globe and use principal component analyses and multiple regression to assess similarity between the climatic variation described by both variable sets. Results: We find that the most commonly used SDM variables do not reflect the most important physiological variables and differ in two main ways: (i) SDM variables rely on seasonal or annual rainfall as simple proxies of water available to plants and neglect more direct measures such as soil water content; and (ii) SDM variables are typically averaged across seasons or years and overlook the importance of climatic events within the critical growth period of plants. We identify notable differences in their spatial gradients globally and show where distal variables may be less reliable proxies for the variables to which species are known to respond. Main conclusions: There is a growing need for the development of accessible, fine-resolution global climate surfaces of physiological variables. This would provide a means to improve the reliability of future range predictions from SDMs and support efforts to conserve biodiversity in a changing climate

    Conceptualizing pathways linking women's empowerment and prematurity in developing countries.

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    BackgroundGlobally, prematurity is the leading cause of death in children under the age of 5. Many efforts have focused on clinical approaches to improve the survival of premature babies. There is a need, however, to explore psychosocial, sociocultural, economic, and other factors as potential mechanisms to reduce the burden of prematurity. Women's empowerment may be a catalyst for moving the needle in this direction. The goal of this paper is to examine links between women's empowerment and prematurity in developing settings. We propose a conceptual model that shows pathways by which women's empowerment can affect prematurity and review and summarize the literature supporting the relationships we posit. We also suggest future directions for research on women's empowerment and prematurity.MethodsThe key words we used for empowerment in the search were "empowerment," "women's status," "autonomy," and "decision-making," and for prematurity we used "preterm," "premature," and "prematurity." We did not use date, language, and regional restrictions. The search was done in PubMed, Population Information Online (POPLINE), and Web of Science. We selected intervening factors-factors that could potentially mediate the relationship between empowerment and prematurity-based on reviews of the risk factors and interventions to address prematurity and the determinants of those factors.ResultsThere is limited evidence supporting a direct link between women's empowerment and prematurity. However, there is evidence linking several dimensions of empowerment to factors known to be associated with prematurity and outcomes for premature babies. Our review of the literature shows that women's empowerment may reduce prematurity by (1) preventing early marriage and promoting family planning, which will delay age at first pregnancy and increase interpregnancy intervals; (2) improving women's nutritional status; (3) reducing domestic violence and other stressors to improve psychological health; and (4) improving access to and receipt of recommended health services during pregnancy and delivery to help prevent prematurity and improve survival of premature babies.ConclusionsWomen's empowerment is an important distal factor that affects prematurity through several intervening factors. Improving women's empowerment will help prevent prematurity and improve survival of preterm babies. Research to empirically show the links between women's empowerment and prematurity is however needed

    Social Control in Transnational Families: Somali Women and Dignity in Johannesburg

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    Transnational mobility often separates families and distances individuals from the kinship and social structures by which they organized their lives prior to migration. Myriad forms of insecurity have been the impetus for Somali movement into the diaspora, with people fleeing the realities of conflict that have marked Somalia for decades while physically dividing families as individuals settle in different countries around the world. Mobility has altered the dynamics of households, families, and communities post-migration, reshaping social constructions as individuals move on without the familial support that sustained them in Somalia. While outcomes of these hardships are variable and often uneven in different settlement spaces, migration can offer new opportunities for people to pursue avenues from which they were previously excluded, such as by assuming roles and responsibilities their relatives once filled. These changes precipitate shifting identities and are challenging for women who find themselves self-reliant in the diaspora, particularly in the absence of (supportive) husbands and close kin.Drawing on ethnographic research in Johannesburg’s Somali community, this chapter explores the assumption that migration provides an opening for women to challenge subordinating gender norms. Settlement often grants women greater freedom to make choices in their lives, such as in employment and personal relationships, and yet they remain constrained by networks that limit their autonomy. Even with transnational migration and protracted separation, women are family representatives who must uphold cultural notions of respectability despite realities that position them as guardians and family providers. Women remain under the watchful eye of their extended families through expansive networks and the ease of modern communication, which facilitate a new form of social control as women’s behavior is carefully monitored and reported to relatives afar. These actualities raise questions about the degree to which transnational movement is a liberating force for women or rather a reconfiguration of social control. I argue that despite women’s changing position in their households and families, they remain limited by social control within their extended families and communities

    Global maps of soil temperature

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    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0\u20135 and 5\u201315 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10\ub0C (mean = 3.0 \ub1 2.1\ub0C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 \ub1 2.3\ub0C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler ( 120.7 \ub1 2.3\ub0C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    Xpf and Not the Fanconi Anaemia Proteins or Rev3 Accounts for the Extreme Resistance to Cisplatin in Dictyostelium discoideum

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    Organisms like Dictyostelium discoideum, often referred to as DNA damage “extremophiles”, can survive exposure to extremely high doses of radiation and DNA crosslinking agents. These agents form highly toxic DNA crosslinks that cause extensive DNA damage. However, little is known about how Dictyostelium and the other “extremophiles” can tolerate and repair such large numbers of DNA crosslinks. Here we describe a comprehensive genetic analysis of crosslink repair in Dictyostelium discoideum. We analyse three gene groups that are crucial for a replication-coupled repair process that removes DNA crosslinks in higher eukarya: The Fanconi anaemia pathway (FA), translesion synthesis (TLS), and nucleotide excision repair. Gene disruption studies unexpectedly reveal that the FA genes and the TLS enzyme Rev3 play minor roles in tolerance to crosslinks in Dictyostelium. However, disruption of the Xpf nuclease subcomponent results in striking hypersensitivity to crosslinks. Genetic interaction studies reveal that although Xpf functions with FA and TLS gene products, most Xpf mediated repair is independent of these two gene groups. These results suggest that Dictyostelium utilises a distinct Xpf nuclease-mediated repair process to remove crosslinked DNA. Other DNA damage–resistant organisms and chemoresistant cancer cells might adopt a similar strategy to develop resistance to DNA crosslinking agents
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