63 research outputs found

    Two-dimensional simulation of the electron transport in a photomultiplier tube

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    Photomultiplier tubes are widely used in experimental physics because they convert small light signals into a measurable electric current. Although their working principle is well known, it is very difficult to find simulations of the electron transport in these devices. For this reason, the electron transport in the Hamamatsu R13408-100 photomultiplier tube has been simulated in 2D. The software SUPERFISH is used for calculating the electrostatic fields and the Boris method for the effective electron dynamics. The secondary electron emission in the dynodes is implemented using an effective electron model and the modified Vaughan’s model. Some figures of merit for photomultiplier tubes (e.g. the gain, the electron transit time or the transit time spread) in function of the supply voltage and an external magnetic field have been studied obtaining a good qualitative accordance with the Hamamatsu datasheet. In further studies, we are going to compare our simulations with experimental measurements

    What have we learnt from EUPORIAS climate service prototypes?

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    The international effort toward climate services, epitomised by the development of the Global Framework for Climate Services and, more recently the launch of Copernicus Climate Change Service has renewed interest in the users and the role they can play in shaping the services they will eventually use. Here we critically analyse the results of the five climate service prototypes that were developed as part of the EU funded project EUPORIAS. Starting from the experience acquired in each of the projects we attempt to distil a few key lessons which, we believe, will be relevant to the wider community of climate service developers

    Investigation of PTC124-mediated translational readthrough in a retinal organoid model of AIPL1-associated Leber congenital amaurosis

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    Leber congenital amaurosis type 4 (LCA4), caused by AIPL1 mutations, is characterized by severe sight impairment in infancy and rapidly progressing degeneration of photoreceptor cells. We generated retinal organoids using induced pluripotent stem cells (iPSCs) from renal epithelial cells obtained from four children with AIPL1 nonsense mutations. iPSC-derived photoreceptors exhibited the molecular hallmarks of LCA4, including undetectable AIPL1 and rod cyclic guanosine monophosphate (cGMP) phosphodiesterase (PDE6) compared with control or CRISPR-corrected organoids. Increased levels of cGMP were detected. The translational readthrough-inducing drug (TRID) PTC124 was investigated as a potential therapeutic agent. LCA4 retinal organoids exhibited low levels of rescue of full-length AIPL1. However, this was insufficient to fully restore PDE6 in photoreceptors and reduce cGMP. LCA4 retinal organoids are a valuable platform for in vitro investigation of novel therapeutic agents

    Incidence of Diabetes in the Working Population in Spain: Results from the ICARIA Cohort

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    INTRODUCTION: Our objective was to evaluate the incidence of type 2 diabetes mellitus (T2DM) in a working population in Spain and to assess associations between its development and several risk factors. METHODS: The ICARIA (Ibermutuamur CArdiovascular RIsk Assessment) cohort (n = 627,523) includes ~3% of Spanish workers. This analysis was undertaken in individuals whose glycaemic status during the index period (May 2004-December 2007) was determined to be normal or indicative of prediabetes [fasting plasma glucose (FPG) 100-125 mg/dl] and who had at least one FPG measurement taken 9 months after a first measurement during follow-up (May 2004-June 2014) (n = 380,366). T2DM patients were defined as those with an FPG ? 126 mg/day and those who had already been diagnosed with T2DM or were taking antihyperglycaemic medications. RESULTS: The incidence rate of T2DM was 5.0 [95% confidence interval (CI) 4.9-5.1] cases per 1000 person-years. Under multivariate logistic regression analysis, the factor showing the strongest association with the occurrence of T2DM was the baseline FPG level, with the likelihood of T2DM almost doubling for every 5 mg/dl increase in baseline FPG between 100 and < 126 mg/dl. The presence of other cardiometabolic risk factors and being a blue-collar worker were also significantly associated with the occurrence of T2DM. CONCLUSIONS: The incidence of T2DM in the working population was within the range encountered in the general population and prediabetes was found to be the strongest risk factor for the development of diabetes. The workplace is an appropriate and feasible setting for the assessment of easily measurable risk factors, such as the presence of prediabetes and other cardiometabolic factors, to facilitate the early detection of individuals at higher risk of diabetes and the implementation of diabetes prevention programmes

    PP2A ligand ITH12246 protects against memory impairment and focal cerebral ischemia in mice

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    ITH12246 (ethyl 5-amino-2-methyl-6,7,8,9-tetrahydrobenzo[b][1,8] naphthyridine-3-carboxylate) is a 1,8-naphthyridine described to feature an interesting neuroprotective profile in in vitro models of Alzheimer's disease. These effects were proposed to be due in part to a regulatory action on protein phosphatase 2A inhibition, as it prevented binding of its inhibitor okadaic acid. We decided to investigate the pharmacological properties of ITH12246, evaluating its ability to counteract the memory impairment evoked by scopolamine, a muscarinic antagonist described to promote memory loss, as well as to reduce the infarct volume in mice suffering phototrombosis. Prior to conducting these experiments, we confirmed its in vitro neuroprotective activity against both oxidative stress and Ca2+ overload-derived excitotoxicity, using SH-SY5Y neuroblastoma cells and rat hippocampal slices. Using a predictive model of blood-brain barrier crossing, it seems that the passage of ITH12246 is not hindered. Its potential hepatotoxicity was observed only at very high concentrations, from 0.1 mM. ITH12246, at the concentration of 10 mg/kg i.p., was able to improve the memory index of mice treated with scopolamine, from 0.22 to 0.35, in a similar fashion to the well-known Alzheimer's disease drug galantamine 2.5 mg/kg. On the other hand, ITH12246, at the concentration of 2.5 mg/kg, reduced the phototrombosis-triggered infarct volume by 67%. In the same experimental conditions, 15 mg/kg melatonin, used as control standard, reduced the infarct volume by 30%. All of these findings allow us to consider ITH12246 as a new potential drug for the treatment of neurodegenerative diseases, which would act as a multifactorial neuroprotectant.Peer Reviewe

    Earth System Model Evaluation Tool (ESMValTool) v2.0 - An extended set of large-scale diagnostics for quasi-operational and comprehensive evaluation of Earth system models in CMIP

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    The Earth System Model Evaluation Tool (ESMValTool) is a community diagnostics and performance metrics tool designed to improve comprehensive and routine evaluation of Earth system models (ESMs) participating in the Coupled Model Intercomparison Project (CMIP). It has undergone rapid development since the first release in 2016 and is now a well-tested tool that provides end-to-end provenance tracking to ensure reproducibility. It consists of (1) an easy-to-install, well-documented Python package providing the core functionalities (ESMValCore) that performs common preprocessing operations and (2) a diagnostic part that includes tailored diagnostics and performance metrics for specific scientific applications. Here we describe large-scale diagnostics of the second major release of the tool that supports the evaluation of ESMs participating in CMIP Phase 6 (CMIP6). ESMValTool v2.0 includes a large collection of diagnostics and performance metrics for atmospheric, oceanic, and terrestrial variables for the mean state, trends, and variability. ESMValTool v2.0 also successfully reproduces figures from the evaluation and projections chapters of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) and incorporates updates from targeted analysis packages, such as the NCAR Climate Variability Diagnostics Package for the evaluation of modes of variability, the Thermodynamic Diagnostic Tool (TheDiaTo) to evaluate the energetics of the climate system, as well as parts of AutoAssess that contains a mix of top-down performance metrics. The tool has been fully integrated into the Earth System Grid Federation (ESGF) infrastructure at the Deutsches Klimarechenzentrum (DKRZ) to provide evaluation results from CMIP6 model simulations shortly after the output is published to the CMIP archive. A result browser has been implemented that enables advanced monitoring of the evaluation results by a broad user community at much faster timescales than what was possible in CMIP5

    High overlap between traditional ecological knowledge and forest conservation found in the Bolivian Amazon

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    Unidad de excelencia MarĂ­a de Maeztu MdM-2015-0552Altres ajuts: FBBVA research grant (BIOCON_06_106-07)It has been suggested that traditional ecological knowledge (TEK) may play a key role in forest conservation. However, empirical studies assessing to what extent TEK is associated with forest conservation compared with other variables are rare. Furthermore, to our knowledge, the spatial overlap of TEK and forest conservation has not been evaluated at fine scales. In this paper, we address both issues through a case study with Tsimane' Amerindians in the Bolivian Amazon. We sampled 624 households across 59 villages to estimate TEK and used remote sensing data to assess forest conservation. We ran statistical and spatial analyses to evaluate whether TEK was associated and spatially overlapped with forest conservation at the village level. We find that Tsimane' TEK is significantly and positively associated with forest conservation although acculturation variables bear stronger and negative associations with forest conservation. We also find a very significant spatial overlap between levels of Tsimane' TEK and forest conservation. We discuss the potential reasons underpinning our results, which provide insights that may be useful for informing policies in the realms of development, conservation, and climate. We posit that the protection of indigenous cultural systems is vital and urgent to create more effective policies in such realms

    Traditional knowledge and cultural importance of Borassus aethiopum Mart. in Benin: interacting effects of socio-demographic attributes and multi-scale abundance

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    ResearchBackground: Eliciting factors affecting distribution of traditional knowledge (TK) and cultural importance of plant resources is central in ethnobiology. Socio-demographic attributes and ecological apparency hypothesis (EAH) have been widely documented as drivers of TK distribution, but their synergistic effect is poorly documented. Here, we focused on Borassus aethiopum, a socio-economic important agroforestry palm in Africa, analyzing relationships between the number of use-reports and cultural importance on one hand, and informant socio-demographic attributes (age category and gender) on the other hand, considering the EAH at multi-scale contexts. Our hypothesis is that effects of socio-demographic attributes on use-reports and cultural importance are shaped by both local (village level) and regional (chorological region level) apparency of study species. We expected so because distribution of knowledge on a resource in a community correlates to the versatility in the resource utilization but also connections among communities within a region. Methods: Nine hundred ninety-two face-to-face individual semi-structured interviews were conducted in six villages of low versus high local abundance of B. aethiopum spanning three chorological regions (humid, sub-humid and semiarid) also underlying a gradient of increasing distribution and abundance of B. aethiopum. Number of use-reports and score of importance of uses of B. aethiopum were recorded in six use-categories including medicine, food, handcraft, construction, firewood, and ceremonies and rituals. Data were analyzed using Poisson and ordered logistic modelsinfo:eu-repo/semantics/publishedVersio

    JC Virus Small t Antigen Binds Phosphatase PP2A and Rb Family Proteins and Is Required for Efficient Viral DNA Replication Activity

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    BACKGROUND: The human polyomavirus, JC virus (JCV) produces five tumor proteins encoded by transcripts alternatively spliced from one precursor messenger RNA. Significant attention has been given to replication and transforming activities of JCV's large tumor antigen (TAg) and three T' proteins, but little is known about small tumor antigen (tAg) functions. Amino-terminal sequences of tAg overlap with those of the other tumor proteins, but the carboxy half of tAg is unique. These latter sequences are the least conserved among the early coding regions of primate polyomaviruses. METHODOLOGY AND FINDINGS: We investigated the ability of wild type and mutant forms of JCV tAg to interact with cellular proteins involved in regulating cell proliferation and survival. The JCV P99A tAg is mutated at a conserved proline, which in the SV40 tAg is required for efficient interaction with protein phosphatase 2A (PP2A), and the C157A mutant tAg is altered at one of two newly recognized LxCxE motifs. Relative to wild type and C157A tAgs, P99A tAg interacts inefficiently with PP2A in vivo. Unlike SV40 tAg, JCV tAg binds to the Rb family of tumor suppressor proteins. Viral DNAs expressing mutant t proteins replicated less efficiently than did the intact JCV genome. A JCV construct incapable of expressing tAg was replication-incompetent, a defect not complemented in trans using a tAg-expressing vector. CONCLUSIONS: JCV tAg possesses unique properties among the polyomavirus small t proteins. It contributes significantly to viral DNA replication in vivo; a tAg null mutant failed to display detectable DNA replication activity, and a tAg substitution mutant, reduced in PP2A binding, was replication-defective. Our observation that JCV tAg binds Rb proteins, indicates all five JCV tumor proteins have the potential to influence cell cycle progression in infected and transformed cells. It remains unclear how these proteins coordinate their unique and overlapping functions

    The 2024 Europe report of the Lancet Countdown on health and climate change: unprecedented warming demands unprecedented action

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    Record-breaking temperatures were recorded across the globe in 2023. Without climate action, adverse climate-related health impacts are expected to worsen worldwide, affecting billions of people. Temperatures in Europe are warming at twice the rate of the global average, threatening the health of populations across the continent and leading to unnecessary loss of life. The Lancet Countdown in Europe was established in 2021, to assess the health profile of climate change aiming to stimulate European social and political will to implement rapid health-responsive climate mitigation and adaptation actions. In 2022, the collaboration published its indicator report, tracking progress on health and climate change via 33 indicators and across five domains. This new report tracks 42 indicators highlighting the negative impacts of climate change on human health, the delayed climate action of European countries, and the missed opportunities to protect or improve health with health-responsive climate action. The methods behind indicators presented in the 2022 report have been improved, and nine new indicators have been added, covering leishmaniasis, ticks, food security, health-care emissions, production and consumption-based emissions, clean energy investment, and scientific, political, and media engagement with climate and health. Considering that negative climate-related health impacts and the responsibility for climate change are not equal at the regional and global levels, this report also endeavours to reflect on aspects of inequality and justice by highlighting at-risk groups within Europe and Europe's responsibility for the climate crisis
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