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  • The potential consequences of a major radiological event are not only large-scale external radiation exposure of the population, but also uncontrolled dissemination of, and internal contamination with, radionuclides. When planning an emergency response to radiological and nuclear incidents, one must consider the need for not only post-exposure treatment for contaminated individuals, but also prophylactic measures to protect the workforce facing contaminated areas and patients in the aftermath of such events. In addition to meeting the desired criteria for post-exposure treatments such as safety, ease of administration, and broad-spectrum efficacy against multiple radionuclides and levels of challenge, ideal prophylactic countermeasures must include rapid onset; induce minimal to no performance-decrementing side effects; be compatible with current military Chemical, Biological, Radiological, Nuclear, and Explosive countermeasures; and require minimal logistical burdens. Hydroxypyridinone-based actinide decorporation agents have shown the most promise as decorporation strategies for various radionuclides of concern, including the actinides plutonium and americium. The studies presented here probe the extent of plutonium decorporation efficacy for two chelating agents, 3,4,3-LI(1,2-HOPO) and 5-LIO(Me-3,2-HOPO), from early pre-exposure time points to a delay of up to 7 days in parenteral or oral treatment administration, i.e., well beyond the initial hours of emergency response. Despite delayed treatment after a contamination event, both ligands clearly enhanced plutonium elimination through the investigated 7-day post-treatment period. In addition, a remarkable prophylactic efficacy was revealed for 3,4,3-LI(1,2-HOPO) with treatment as early as 48 h before the plutonium challenge. This work provides new perspectives in the indication and use of experimental actinide decorporation treatments.
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  • Organophosphorus compounds (OP), which mainly penetrate via the percutaneous pathway, represent a threat for both military and civilians. Body surface decontamination is vital to prevent victims poisoning. The development of a cost-effective formulation, which could be efficient and easy to handle in case of mass contamination, is therefore crucial. Metal oxides nanoparticles, due their large surface areas and the large amount of highly reactive sites, present high reactivity towards OP. First, this study aimed at evaluating the reaction of CeO2 nanoparticles, synthetized by microwave path and calcined at 500 or 600 °C, with Paraoxon (POX) in aqueous solution. Results showed that both nanoparticles degraded 60%–70% of POX. CeO2 calcined at 500 °C, owing to its larger specific area, was the most effective. Moreover, the degradation was significantly increased under Ultra-Violet irradiation (initial degradation rate doubled). Then, skin decontamination was studied in vitro using the Franz cell method with pig-ear skin samples. CeO2 powder and an aqueous suspension of CeO2 (CeO2-W) were applied 1 h after POX exposure. The efficiency of decontamination, including removal and/or degradation of POX, was compared to Fuller's earth (FE) and RSDL lotion which are, currently, the most efficient systems for skin decontamination. CeO2-W and RSDL were the most efficient to remove POX from the skin surface and decrease skin absorption by 6.4 compared to the control not decontaminated. FE reduced significantly (twice) the absorbed fraction of POX, contrarily to CeO2 powder. Considering only the degradation rate of POX, the products ranged in the order CeO2 > RSDL > CeO2-W > FE (no degradation). This study showed that CeO2 nanoparticles are a promising material for skin decontamination of OP if formulated as a dispersion able to remove POX like CeO2-W and to degrade it as CeO2 powder.
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  • Developing countries have urbanized rapidly since 1950. To explain urbanization, standard models emphasize rural–urban migration, focusing on rural push factors (agricultural modernization and rural poverty) and urban pull factors (industrialization and urban-biased policies). Using new historical data on urban birth and death rates for 7 countries from Industrial Europe (1800–1910) and 35 developing countries (1960–2010), we argue that a non-negligible part of developing countries’ rapid urban growth and urbanization may also be linked to demographic factors, i.e. rapid internal urban population growth, or an urban push. High urban natural increase in today’s developing countries follows from lower urban mortality, relative to Industrial Europe, where higher urban deaths offset urban births. This compounds the effects of migration and displays strong associations with urban congestion, providing additional insight into the phenomenon of urbanization without growth.
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  • The central nervous system is emerging as an important target for adverse health effects of air pollution, where it may contribute to neurodevelopmental and neurodegenerative disorders. Air pollution comprises several components, including particulate matter (PM) and ultrafine particulate matter (UFPM), gases, organic compounds, and metals. An important source of ambient PM and UFPM is represented by traffic-related air pollution, primarily diesel exhaust (DE). Human epidemiological studies and controlled animal studies have shown that exposure to air pollution, and to traffic-related air pollution or DE in particular, may lead to neurotoxicity. In particular, air pollution is emerging as a possible etiological factor in neurodevelopmental (e.g. autism spectrum disorders) and neurodegenerative (e.g. Alzheimer's disease) disorders. The most prominent effects caused by air pollution in both humans and animals are oxidative stress and neuro-inflammation. Studies in mice acutely exposed to DE (250–300μg/m3 for 6h) have shown microglia activation, increased lipid peroxidation, and neuro-inflammation in various brain regions, particularly the hippocampus and the olfactory bulb. An impairment of adult neurogenesis was also found. In most cases, the effects of DE were more pronounced in male mice, possibly because of lower antioxidant abilities due to lower expression of paraoxonase 2.
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  • This study aims to cluster the world’s top tourist destinations based on the growth of the main tourism indicators over the period between 2000 and 2010. It ranks the destinations with respect to the average growth rate over the sample period. The results find that both China and Turkey are at the top of the rankings of all variables. By assigning a numerical value to each country corresponding to its position, a Spearman’s coefficient is calculated and a negative correlation found between a destination’s dependency on tourism and the profitability of the tourism activity. Finally, several multivariate techniques for dimensionality reduction are used to cluster all destinations according to their positioning. Three groups are obtained: China, Turkey, and the rest of the destinations. These results show that the persistent growth of the tourism industry poses different challenges in different markets regarding destination marketing and management.
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  • Se presenta un caso de manejo complicado y decisiones difíciles. Un paciente con antecedente de disección aórtica tipo A y dilatación residual de la aorta descendente de hasta 60mm es ingresado por un síndrome coronario agudo sin elevación del ST. La coronariografía pone de manifiesto una marcada ectasia coronaria y unos defectos de perfusión de dudoso origen. ¿Trombos o falsas imágenes por flujo muy lentificado? Asumiendo que pudiera tratarse de trombos, el paciente es tratado con anticoagulación repitiéndose la coronariografía al cabo de dos meses. En este segundo estudio se observa la completa desaparición de las imágenes, confirmándose el origen trombótico de las mismas. En este momento se plantea ¿cuál debe ser el tratamiento crónico del paciente? No hay evidencia científica disponible acerca del tratamiento de la ectasia coronaria y se trata de un paciente de alto riesgo por su antecedente de disección aórtica. Finalmente se decide, de forma empírica, mantener la anticoagulación de forma indefinida. Tras dos años y seis meses de seguimiento no ha habido incidencias clínicas.
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  • Through its role as gatekeeper and filter to the external world, the microbiome affects developmental programming of physiological systems including the immune system. In turn, the immune system must tolerate, personalize, and prune the microbiome. Immune and host barrier status in early life significantly effects everything from embryo viability and pregnancy duration to the likelihood of misregulated inflammation, and risk of noncommunicable diseases (NCDs). Since the programming of and interactions among the microbiome, the host defense barrier, and the immune system can affect inflammation-driven health risks across the lifespan, a systems biology-type understanding of these three biological components may be useful. Here, I consider the potential utility of focusing on programming of a newly-defined systems biology unit termed the “microimmunosome.”
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  • This study examines the key characteristics of successful fisheries learning exchanges (FLEs). FLEs are peer-to-peer gatherings in which fishery stakeholders from different communities freely exchange information and experiences surrounding fisheries challenges and solutions. They are usually organized by fishers, non-governmental organizations and governments and are credited as an integral tool for the diffusion and adoption of fisheries management strategies. Despite their numerous perceived benefits within fisheries conservation and management, little research has been conducted on FLEs. This multiple case study addressed the research question: “What are the key characteristics of successful FLEs?” Success metrics were defined during a workshop on FLEs in 2013. For this study, the authors selected six successful FLEs that were presented during the workshop. Documentation of FLEs and key informant interviews with participants and organizers were used as data. The following key elements of successful FLEs emerged from analyses: (1) a clear guiding purpose and flexible objectives, (2) careful and considered selection of participants with diverse professions and conservation beliefs, (3) a mix of activities including giving presentations, conducting site visits, talking with local fishers, spending time on boats or in the water, and participating in cultural activities, and (4) logistical and financial follow-up support, including information dissemination about what participants learned at the FLE. Based on these results, the authors provide recommendations for conducting successful FLEs.
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  • The recent excavations (2008–2009) conducted at the open-air site of Las Delicias, located in the Manzanares River valley (Madrid), have revealed new important data for the understanding of the human settlement of Central Iberia during Solutrean times. In this paper, we present a geomorphological and taphonomic study of the Pleistocene deposits of Las Delicias, a technological analysis focused on the bifacial lithic reduction processes documented at the site, new Optically Stimulated Luminescence dates, and new palynological data. Together with the existence of numerous Solutrean lithic assemblages from the early 20th century excavations of the Manzanares terraces, these new data highlight the importance of the Manzanares valley as a focus of Solutrean settlement, not only related to flint procurement but also to foraging activities. Moreover, they require reconsideration of Central Iberia as a virtually unpopulated region during the Late Pleniglacial (MIS 2), and of the associated idea of its cultural dependence on the coastal areas of the Iberian Peninsula. We propose new avenues of research aimed at approaching the central region of Iberia in its own cultural and ecological terms.
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