23 research outputs found

    Gravel deposit produced by a flash paleoflood in a succession of Quaternary terraces in the Plain of Vic (NE Iberian Peninsula)

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    In contrast with the abundance of studies of fluvial terraces, caused by river dynamics, there are very few descriptions of alluvial deposits produced by flash floods and mass movements. This study describes a late Pleistocene sedimentary deposit produced by a flash paleoflood and attempts to explain its genesis and its source areas. The Plain of Vic, drained by the river Ter and its tributaries, is one of the eastern erosive basins bordering the sedimentary Ebre basin (NE Iberian Peninsula). This plain has a length of 35 km and an average width of 8 km with a N-S direction and lies mainly on the Marls of Vic Fm. These materials are the less resistant lithologic members of the monocline Paleogene stratigraphic succession that dips to the west. The basal resistant bed that forms the eastern cuesta is the Sandstones of Folgueroles Fm. On the top, the resistant lithologic beds that form the scarp face are the sandstones of La Noguera in the Vidrà Fm. On the scarp face, various coalescent alluvial bays have been developed, which have accumulated up to eight levels of alluvial terraces. In one of them, formed by the river Mèder and the Muntanyola stream, a gravel deposit up to 5 m thick formed in a single episode outcrops, in a position T4,. A dating of the river Ter T5 has obtained an age of 117.9 9.5 Ky. The accumulation of gravel erodes another level of metric thickness of the same lithological characteristics and texture. The deposit does not have any internal structure or organization of pebbles. At its base, there are several metric blocks coming directly from the slopes. The accumulation of gravel is block-supported with a sandy matrix. The pebbles size is centimetric to decimetric (90%). Its texture is subrounded. Lithologically, the deposit consists mostly of sandstone and limestone from the top of the series. On the ground, the accumulation of gravel is elongated, with a maximum length and width of 550 m by 160 m and a slope surface of 2.54%. With an area of 56,500 m2, this totals to a volume of 282,500 m3. It is separated 400 m from the inner slope formed by two tributaries, and 100 m from the slope on the right side. The width of the right floodplain is 60 m, and the left one is 20 m wide. The deposit is eroded laterally by several meanders of later episodes which uncovered the accumulation of gravel. This accumulation can be considered as a proximal deposition of a flash paleoflood event in the bay formed by two alluvial tributaries. It cannot be ruled out that higher and older gravel deposits, belonging to T8, have the same genesis. Distally, at a distance of 2,600 m, in the same stratigraphic position (T4) and with an average gradient of 1.26%, a lutitic layer of metric thickness that corresponds to a distal flashflood accumulation outcrops. Understanding the processes that formed this deposit can help gain insight on flash floods and their role in the evolution of geomorphic features and landscapes.Postprint (published version

    Implication of gut microbiota in the physiology of rats intermittently exposed to cold and hypobaric hypoxia

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    This study examines the influence of intermittent exposure to cold, hypobaric hypoxia, and their combination, in gut microbiota and their metabolites in vivo, and explores their effects on the physiology of the host. Sprague-Dawley rats were exposed to cold (4ºC), hypobaric hypoxia (462 torr), or both simultaneously, 4 h/day for 21 days. Biometrical and hematological parameters were monitored. Gut bacterial subgroups were evaluated by qRT-PCR and short-chain fatty acids were determined by gas chromatography in caecum and feces. Cold increased brown adipose tissue, Clostridiales subpopulation and the concentration of butyric and isovaleric acids in caecum. Hypobaric hypoxia increased hemoglobin, red and white cell counts and Enterobacteriales, and reduced body and adipose tissues weights and Lactobacilliales. Cold plus hypobaric hypoxia counteracted the hypoxia-induced weight loss as well as the increase in white blood cells, while reducing the Bacteroidetes:Firmicutes ratio and normalizing the populations of Enterobacteriales and Lactobacilliales. In conclusion, intermittent cold and hypobaric hypoxia exposures by themselves modified some of the main physiological variables in vivo , while their combination kept the rats nearer to their basal status. The reduction of the Bacteroidetes:Firmicutes ratio and balanced populations of Enterobacteriales and Lactobacilliales in the gut may contribute to this effect

    BioBlitz Serra Llarga-Secans de la Noguera 2021: desenvolupament i espècies presents

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    En aquest article es fa la descripció de la tasca duta a terme durant el BioBlitz Serra Llarga-Secans de la Noguera dels dies 21 i 22 de maig de 2021 i es presenta el llistat despècies observades amb lobjectiu de facilitar que aquestes observacions es puguin integrar en les bases de dades públiques de biodiversitat.This paper lists the work carried out during the BioBlitz Serra Llarga-Secans de la Noguera on 21-22 May 2021. We present the list of observed species with the aim of facilitating that these observation could be integrated into public biodiversity databases

    Comparative efficacy of two primary care interventions to assist withdrawal from long term benzodiazepine use: A protocol for a clustered, randomized clinical trial

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    <p>Abstract</p> <p>Background</p> <p>Although benzodiazepines are effective, long-term use is not recommended because of potential adverse effects; the risks of tolerance and dependence; and an increased risk of hip fractures, motor vehicle accidents, and memory impairment. The estimated prevalence of long-term benzodiazepine use in the general population is about 2,2 to 2,6%, is higher in women and increases steadily with age. Interventions performed by General Practitioners may help patients to discontinue long-term benzodiazepine use. We have designed a trial to evaluate the effectiveness and safety of two brief general practitioner-provided interventions, based on gradual dose reduction, and will compare the effectiveness of these interventions with that of routine clinical practice.</p> <p>Methods/Design</p> <p>In a three-arm cluster randomized controlled trial, general practitioners will be randomly allocated to: a) a group in which the first patient visit will feature a structured interview, followed by visits every 2-3 weeks to the end of dose reduction; b) a group in which the first patient visit will feature a structured interview plus delivery of written instructions to self-reduce benzodiazepine dose, or c) routine care. Using a computerized pharmaceutical prescription database, 495 patients, aged 18-80 years, taking benzodiazepine for at least 6 months, will be recruited in primary care health districts of three regions of Spain (the Balearic Islands, Catalonia, and Valencia). The primary outcome will be benzodiazepine use at 12 months. The secondary outcomes will include measurements of anxiety and depression symptoms, benzodiazepine dependence, quality of sleep, and alcohol consumption.</p> <p>Discussion</p> <p>Although some interventions have been shown to be effective in reducing benzodiazepine consumption by long-term users, the clinical relevance of such interventions is limited by their complexity. This randomized trial will compare the effectiveness and safety of two complex stepped care interventions with that of routine care in a study with sufficient statistical power to detect clinically relevant differences.</p> <p>Trial Registration</p> <p>Current Controlled Trials: <a href="http://www.controlled-trials.com/ISRCTN13024375">ISRCTN13024375</a></p

    SemFYC encaminada hacia Horizonte 2020

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