106 research outputs found

    Essais d'estimation des débits de pointe de crue à partir des caractéristiques physiques et climatiques des bassins versants en région méditerranéenne

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    Dans une vallée, la définition des aménagements est étroitement liée aux risques d'inondation, c'est-à-dire à la probabilité de voir une caractéristique de crue, en général la cote maximale, atteindre ou dépasser une certaine valeur. Lorsqu'une station de mesure des hauteurs d'eau existe sur le site et a fonctionné suffisamment longtemps, l'analyse statistique des relevés historiques permet une évaluation correcte du degré de risque. Ces stations sont malheureusement en nombre insuffisant. Leur emplacement correspond rarement au site étudié, voire à la rivière concernée. Par ailleurs, les cotes sont très sensibles aux modifications topographiques (lits, ouvrages, obstacles...) et il vaut mieux travailler d'abord sur les débits, plus stables (régime hydrologique). Il apparaît donc la nécessité de disposer de méthodes d'évaluation des risques de débit en tout point d'une rivière et en absence de contrôle systématique. L'approche développée concerne la région Languedoc-Roussillon et consiste à estimer les débits de pointe de crues à partir de caractéristiques du bassin versant amont et de paramètres régionaux. (Résumé d'auteur

    A murine model of Charcot-Marie-Tooth disease 4F reveals a role for the C-terminus of periaxin in the formation and stabilization of Cajal bands

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    Charcot-Marie-Tooth (CMT) disease comprises up to 80 monogenic inherited neuropathies of the peripheral nervous system (PNS) that collectively result in demyelination and axon degeneration. The majority of CMT disease is primarily either dysmyelinating or demyelinating in which mutations affect the ability of Schwann cells to either assemble or stabilize peripheral nerve myelin. CMT4F is a recessive demyelinating form of the disease caused by mutations in the Periaxin (PRX) gene. Periaxin (Prx) interacts with Dystrophin Related Protein 2 (Drp2) in an adhesion complex with the laminin receptor Dystroglycan (Dag). In mice the Prx/Drp2/Dag complex assembles adhesive domains at the interface between the abaxonal surface of the myelin sheath and the cytoplasmic surface of the Schwann cell plasma membrane. Assembly of these appositions causes the formation of cytoplasmic channels called Cajal bands beneath the surface of the Schwann cell plasma membrane. Loss of either Periaxin or Drp2 disrupts the appositions and causes CMT in both mouse and man. In a mouse model of CMT4F, complete loss of Periaxin first prevents normal Schwann cell elongation resulting in abnormally short internodal distances which can reduce nerve conduction velocity, and subsequently precipitates demyelination. Distinct functional domains responsible for Periaxin homodimerization and interaction with Drp2 to form the Prx/Drp2/Dag complex have been identified at the N-terminus of Periaxin. However, CMT4F can also be caused by a mutation that results in the truncation of Periaxin at the extreme C-terminus with the loss of 391 amino acids. By modelling this in mice, we show that loss of the C-terminus of Periaxin results in a surprising reduction in Drp2. This would be predicted to cause the observed instability of both appositions and myelin, and contribute significantly to the clinical phenotype in CMT4F

    Разработка автоматизированного ИТП жилого здания

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    Объектом разработки системы является жилой дом с инженерными сетями в микрорайоне «Северный» в Заречном поселении Томского района Томской области. Целью работы является разработка системы мониторинга и управления теплопотреблением здания, которая позволит вести точный учет потребляемой тепловой энергии, регулировать объем потребления в зависимости от текущих погодных условий, обеспечивать экономию энергоресурсов. В результате разработана система, содержащая в себе компоненты, позволяющие производить учет и управление теплопотреблением здания. Причем все данные о работе системы, объемах потребления и параметрах теплоносителя поступают диспетчеру, имеющему возможность отслеживать все параметры системы удаленно.The object of the development of the system is a residential building with engineering services in the neighborhood "North" in Zarechny settlement Tomsk region Tomsk region. The aim is to develop a building heat consumption monitoring and control system that will keep accurate records of heat energy consumption, adjusted consumption, depending on the current weather conditions, to ensure energy saving. As a result, we developed a system, which contains the components to allow for registration and control of heat consumption of the building. Moreover, all data on the system performance, volume and consumption parameters receives coolant controller having the ability to track all system parameters remotely

    Environmental impact assessment of wheat straw based alkyl polyglucosides produced using novel chemical approaches

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    This paper evaluates and quantifies the environmental performance of alkyl polyglucosides sourced from wheat straw (WS-APG), a low-cost and low-ecological impact agricultural residue, compared to that of their commercial counterpart, which is sourced from palm kernel oil and wheat grain (PW-APG). Escalating pressure to consider the environmental sustainability of fossil derived surfactant consumption has driven biosurfactants to become the product of choice within the surfactant market, and a class of ‘plant’ based non-ionic surfactants called alkyl polyglucosides (APG) are particularly prevalent. However, the existing food based feedstock of APG such as coconut oil, palm oil, wheat and corn (in addition to being expensive) will potentially undermine the claimed ‘sustainability’ of the APG products (i.e. the ‘food vs. chemical’ issue). Here, we present the “cradle-to-gate” life cycle impact assessment of a suggested alternative, hybridised APG synthesis technique where the Fisher glycosidation method is supplemented by novel, green chemistry based techniques. This evaluation provides a quantitative insight into direct GHG intensity and other ecological impact indicators, including land use, waste generation and energy consumption. Upon evaluation, the wheat straw-derived pathway delivered GHG-emission savings in the range of 84–98%, compared to that of the palm kernel–wheat grain pathway. Waste generated from the production of unit mass of the product amounted to 0.43 kg and 10.73 kg per kg of WS-APG and PW-APG, respectively. In addition to the above mentioned facts, the ‘cradle–gate’ stages of WS-APG production were also found to consume relatively lower amounts of water and fossil-derived energy. In conclusion, of the two APG production pathways, the suggested ‘hybrid’ pathway using an agricultural residue, wheat straw, was found to be sustainable and to demonstrate better environmental performance

    Absence of Dystrophin Related Protein-2 disrupts Cajal bands in a patient with Charcot-Marie-Tooth disease

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    Using exome sequencing in an individual with Charcot-Marie-Tooth disease (CMT) we have identified a mutation in the X-linked dystrophin-related protein 2 (DRP2) gene. A 60-year-old gentleman presented to our clinic and underwent clinical, electrophysiological and skin biopsy studies. The patient had clinical features of a length dependent sensorimotor neuropathy with an age of onset of 50 years. Neurophysiology revealed prolonged latencies with intermediate conduction velocities but no conduction block or temporal dispersion. A panel of 23 disease causing genes was sequenced and ultimately was uninformative. Whole exome sequencing revealed a stop mutation in DRP2, c.805C>T (Q269*). DRP2 interacts with periaxin and dystroglycan to form the periaxin-DRP2-dystroglycan complex which plays a role in the maintenance of the well-characterized Cajal bands of myelinating Schwann cells. Skin biopsies from our patient revealed a lack of DRP2 in myelinated dermal nerves by immunofluorescence. Furthermore electron microscopy failed to identify Cajal bands in the patient's dermal myelinated axons in keeping with ultrastructural pathology seen in the Drp2 knockout mouse. Both the electrophysiologic and dermal nerve twig pathology support the interpretation that this patient's DRP2 mutation causes characteristic morphological abnormalities recapitulating the Drp2 knockout model and potentially represents a novel genetic cause of CMT

    Robust open cellular porous polymer monoliths made from cured colloidal gels of latex particles

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    The coagulation of oppositely charged latexes, prepared from the soap-free emulsion polymerisation of styrene using water as the reaction medium, resulted in the obtainment of colloidal gels that were porous in nature and held together by electrostatic interactions. Chemical crosslinking, involving the introduction of a water-soluble crosslinker, resulted in the obtainment of stronger chemical bonds between particles affording a rigid porous material known as a monolith. It was found that, in a simpler approach, these materials could be prepared using a single latex where the addition of ammonium persulfate both resulted in the formation of the colloidal gel and initiated the crosslinking process. The pore size of the resulting monoliths was predictable as this was observed to directly correlate to the particle diameter, with larger pores achieved using particles of increased size. All gels obtained in this work were highly mouldable and retained their shape, which allowed for a range of formats to be easily prepared without the requirement of a mould
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