78 research outputs found

    3D-моделирование для жизненного цикла сооружения

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    Owners and construction management are in permanent search to increase competitiveness, reduce cost and time and maintain a high quality of products and services. In this objective project management tend to organize work execution by implementing comprehensive, linked and sequential processes, making full use of every work effort and limiting work duplication and rework. Since the ’90s, the 3D-modeling is used to coordinate, plan, build and manage future structures. The BIM approach proposes to stakeholders to participate in an intelligent centrally shared 3D-model making use of every contribution to this model, facilitating the coordination, solving the interfaces, reducing duplication efforts and carrying the developed data information throughout the life cycle of the structure and beyond the construction phase. Completing a complex structure requires an important level of design management and coordination of the interface between architect, designer, mechanic, electrician, and other designers. Basic input is required from equipment suppliers. Now, for a good reason, everyone in charge of the process is focused on achieving their process with less cost and less time. Thus, he inadvertently reduces the effort associated with surrounding or subsequent actions, and focuses on his main result. For example, structural engineering developing a 3D-model will focus on clean structural design focusing on structural continuity, geometry identification, and calculation model for finite elements of software. Likewise, a mechanical engineer will model plumbing and mechanical networks for fabrication and installation purposes. It is the same with other design disciplines.Собственники и руководители строительства находятся в постоянном процессе повышения конкурентоспособности, сокращения затрат и времени, поддержания высокого качества продукции и услуг. Цель управления проектами – организовать выполнение работ путем реализации комплексных, связанных и последовательных мероприятий, в полной мере использовать ограничения дублирования переделок. С 1990-х годов 3D-моделирование используется для координации, планирования, создания и эксплуатации будущего сооружения. BIM-подход предлагает заинтересованным сторонам участвовать в общей интеллектуальной 3D-модели, облегчая координацию, решая интерфейсы, уменьшая усилия по дублированию и сохраняя информацию о разработанных данных на протяжении всего жизненного цикла конструкции и по завершении этапа строительства. Для выполнения сложной структуры взаимодействия необходимы высокий уровень управления проектированием и координация интерфейса между архитектором, конструктором, механиком, электриком и другими проектировщиками. От поставщиков оборудования требуются основные входные данные. В связи с этим каждый ответственный за процесс нацелен на достижение собственного результата с меньшими затратами и временем исполнения. Тем самым он непреднамеренно сокращает усилия, связанные с сопутствующими действиями, и сосредоточивается на своем основном результате. Например, структурная инженерия, разрабатывающая  3D-модель, будет нацелена на чистый структурный дизайн, ориентируясь на непрерывность конструкции, идентификацию геометрии и модель расчета для конечных элементов программного обеспечения. Точно так же будут моделироваться водопроводные и другие сети для изготовления и монтажа

    Evolutionary history of hepatitis C virus genotype 5a in France, a multicenter ANRS study

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    The epidemic history of HCV genotype 5a is poorly documented in France, where its prevalence is very low, except in a small central area, where it accounts for 14.2% of chronic hepatitis C cases. A Bayesian coalescent phylogenetic investigation based on the E1 envelope gene and a non-structural genomic segment (NS3/4) was carried out to trace the origin of this epidemic using a large sample of genotype 5a isolates collected throughout France. The dates of documented transmissions by blood transfusion were used to calibrate five nodes in the phylogeny. The results of the E1 gene analysis showed that the best-fitting population dynamic model was the expansion growth model under a relaxed molecular clock. The rate of nucleotide substitutions and time to the most recent common ancestors (tMRCA) of genotype 5a isolates were estimated. The divergence of all the French HCV genotype 5a strains included in this study was dated to 1939 [95% HPD: 1921–1956], and the tMRCA of isolates from central France was dated to 1954 [1942–1967], which is in agreement with epidemiological data. NS3/4 analysis provided similar estimates with strongly overlapping HPD values. Phylodynamic analyses give a plausible reconstruction of the evolutionary history of HCV genotype 5a in France, suggesting the concomitant roles of transfusion, iatrogenic route and intra-familial transmission in viral diffusion

    Metabolic Impact of Adult-Onset, Isolated, Growth Hormone Deficiency (AOiGHD) Due to Destruction of Pituitary Somatotropes

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    Growth hormone (GH) inhibits fat accumulation and promotes protein accretion, therefore the fall in GH observed with weight gain and normal aging may contribute to metabolic dysfunction. To directly test this hypothesis a novel mouse model of adult onset-isolated GH deficiency (AOiGHD) was generated by cross breeding rat GH promoter-driven Cre recombinase mice (Cre) with inducible diphtheria toxin receptor mice (iDTR) and treating adult Cre+/−,iDTR+/− offspring with DT to selectively destroy the somatotrope population of the anterior pituitary gland, leading to a reduction in circulating GH and IGF-I levels. DT-treated Cre−/−,iDTR+/− mice were used as GH-intact controls. AOiGHD improved whole body insulin sensitivity in both low-fat and high-fat fed mice. Consistent with improved insulin sensitivity, indirect calorimetry revealed AOiGHD mice preferentially utilized carbohydrates for energy metabolism, as compared to GH-intact controls. In high-fat, but not low-fat fed AOiGHD mice, fat mass increased, hepatic lipids decreased and glucose clearance and insulin output were impaired. These results suggest the age-related decline in GH helps to preserve systemic insulin sensitivity, and in the context of moderate caloric intake, prevents the deterioration in metabolic function. However, in the context of excess caloric intake, low GH leads to impaired insulin output, and thereby could contribute to the development of diabetes

    Maternal Obesity during Gestation Impairs Fatty Acid Oxidation and Mitochondrial SIRT3 Expression in Rat Offspring at Weaning

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    In utero exposure to maternal obesity increases the offspring's risk of obesity in later life. We have also previously reported that offspring of obese rat dams develop hepatic steatosis, mild hyperinsulinemia, and a lipogenic gene signature in the liver at postnatal day (PND)21. In the current study, we examined systemic and hepatic adaptations in male Sprague-Dawley offspring from lean and obese dams at PND21. Indirect calorimetry revealed decreases in energy expenditure (p<0.001) and increases in RER values (p<0.001), which were further exacerbated by high fat diet (45% kcals from fat) consumption indicating an impaired ability to utilize fatty acids in offspring of obese dams as analyzed by PRCF. Mitochondrial function is known to be associated with fatty acid oxidation (FAO) in the liver. Several markers of hepatic mitochondrial function were reduced in offspring of obese dams. These included SIRT3 mRNA (p = 0.012) and mitochondrial protein content (p = 0.002), electron transport chain complexes (II, III, and ATPase), and fasting PGC-1α mRNA expression (p<0.001). Moreover, hepatic LCAD, a SIRT3 target, was not only reduced 2-fold (p<0.001) but was also hyperacetylated in offspring of obese dams (p<0.005) suggesting decreased hepatic FAO. In conclusion, exposure to maternal obesity contributes to early perturbations in whole body and liver energy metabolism. Mitochondrial dysfunction may be an underlying event that reduces hepatic fatty acid oxidation and precedes the development of detrimental obesity associated co-morbidities such as insulin resistance and NAFLD

    Clinical spectrum of MTOR-related hypomelanosis of Ito with neurodevelopmental abnormalities

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    PURPOSE: Hypomelanosis of Ito (HI) is a skin marker of somatic mosaicism. Mosaic MTOR pathogenic variants have been reported in HI with brain overgrowth. We sought to delineate further the pigmentary skin phenotype and clinical spectrum of neurodevelopmental manifestations of MTOR-related HI. METHODS: From two cohorts totaling 71 patients with pigmentary mosaicism, we identified 14 patients with Blaschko-linear and one with flag-like pigmentation abnormalities, psychomotor impairment or seizures, and a postzygotic MTOR variant in skin. Patient records, including brain magnetic resonance image (MRI) were reviewed. Immunostaining (n = 3) for melanocyte markers and ultrastructural studies (n = 2) were performed on skin biopsies. RESULTS: MTOR variants were present in skin, but absent from blood in half of cases. In a patient (p.[Glu2419Lys] variant), phosphorylation of p70S6K was constitutively increased. In hypopigmented skin of two patients, we found a decrease in stage 4 melanosomes in melanocytes and keratinocytes. Most patients (80%) had macrocephaly or (hemi)megalencephaly on MRI. CONCLUSION: MTOR-related HI is a recognizable neurocutaneous phenotype of patterned dyspigmentation, epilepsy, intellectual deficiency, and brain overgrowth, and a distinct subtype of hypomelanosis related to somatic mosaicism. Hypopigmentation may be due to a defect in melanogenesis, through mTORC1 activation, similar to hypochromic patches in tuberous sclerosis complex

    Genetic Dissection of Strain Dependent Paraquat-induced Neurodegeneration in the Substantia Nigra Pars Compacta

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    The etiology of the vast majority of Parkinson's disease (PD) cases is unknown. It is generally accepted that there is an interaction between exposures to environmental agents with underlying genetic sensitivity. Recent epidemiological studies have shown that people living in agricultural communities have an increased risk of PD. Within these communities, paraquat (PQ) is one of the most utilized herbicides. PQ acts as a direct redox cycling agent to induce formation of free radicals and when administered to mice induces the cardinal symptoms of parkinsonism, including loss of TH+-positive dopaminergic (DA) neurons in the ventral midbrain's substantia nigra pars compacta (SNpc). Here we show that PQ-induced SNpc neuron loss is highly dependent on genetic background: C57BL/6J mice rapidly lose ∼50% of their SNpc DA neurons, whereas inbred Swiss-Webster (SWR/J) mice do not show any significant loss. We intercrossed these two strains to map quantitative trait loci (QTLs) that underlie PQ-induced SNpc neuron loss. Using genome-wide linkage analysis we detected two significant QTLs. The first is located on chromosome 5 (Chr 5) centered near D5Mit338, whereas the second is on Chr 14 centered near D14Mit206. These two QTLs map to different loci than a previously identified QTL (Mptp1) that controls a significant portion of strain sensitivity to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), suggesting that the mechanism of action of these two parkinsonian neurotoxins are different

    The Early Nutritional Environment of Mice Determines the Capacity for Adipose Tissue Expansion by Modulating Genes of Caveolae Structure

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    While the phenomenon linking the early nutritional environment to disease susceptibility exists in many mammalian species, the underlying mechanisms are unknown. We hypothesized that nutritional programming is a variable quantitative state of gene expression, fixed by the state of energy balance in the neonate, that waxes and wanes in the adult animal in response to changes in energy balance. We tested this hypothesis with an experiment, based upon global gene expression, to identify networks of genes in which expression patterns in inguinal fat of mice have been altered by the nutritional environment during early post-natal development. The effects of over- and under-nutrition on adiposity and gene expression phenotypes were assessed at 5, 10, 21 days of age and in adult C57Bl/6J mice fed chow followed by high fat diet for 8 weeks. Under-nutrition severely suppressed plasma insulin and leptin during lactation and diet-induced obesity in adult mice, whereas over-nourished mice were phenotypically indistinguishable from those on a control diet. Food intake was not affected by under- or over-nutrition. Microarray gene expression data revealed a major class of genes encoding proteins of the caveolae and cytoskeleton, including Cav1, Cav2, Ptrf (Cavin1), Ldlr, Vldlr and Mest, that were highly associated with adipose tissue expansion in 10 day-old mice during the dynamic phase of inguinal fat development and in adult animals exposed to an obesogenic environment. In conclusion gene expression profiles, fat mass and adipocyte size in 10 day old mice predicted similar phenotypes in adult mice with variable diet-induced obesity. These results are supported by phenotypes of KO mice and suggest that when an animal enters a state of positive energy balance adipose tissue expansion is initiated by coordinate changes in mRNA levels for proteins required for modulating the structure of the caveolae to maximize the capacity of the adipocyte for lipid storage
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