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Neural Computing and Applications - In this paper, we present the novel Deep-MEG approach in which image-based representations of magnetoencephalography (MEG) data are combined with ensemble...  相似文献   
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The preparation of highly aromatic elastomers from a bisphenol A-based divinyl-terminated resin and polymerization with various aromatic silane containing compounds utilizing a room temperature hydrosilylation reaction is demonstrated. The polymers exhibit high thermal and oxidative stability with 5% weight losses around 430 and 350°C and char yields ranging from 35% to 40%. The thermosets maintained their elastomeric properties with good hardness and mechanical properties as measured by elongation measurements. The toughness of the thermosets was not improved with the inclusion of aromatic moieties but the hardness did appear to increase with the addition of more aromatic groups.  相似文献   
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In order to assess the current diagnostic role of the TRH test following the introduction of more sensitive "second generation" TSH assays, we studied a series of 259 outpatients, 237 women and 22 men, mean age 44.7 years (range 12-82), 91 of whom (35%) with untreated simple goiter, 133 (51%) with simple nodular goiter on steady state I-thyroxine treatment, 18 (7%) with overt or subclinical hyperthyroidism and 17 (7%) with overt or subclinical hypothyroidism, compared to a control group of 26 euthyroid healthy subjects. Serum TSH was measured by a commercial immunoradiometric assay (clinical sensitivity 0.1 microU/ml). TSH response to TRH was evaluated 30 minutes after giving 200 micrograms TRH i.v. bolus, the results being analyzed both as absolute increase (delta-TSH=stimulated TSH minus basal TSH) and as relative increase (R-TSH stimulated TSH/basal TSH). Using cut-off values of 0.3-3.2 microU/ml, basal TSH measurement was able to detect hypothyroidism (specificity = 100%) and to exclude hyperthyroidism (sensivity = 96.9%), but failed to accurately prove hyperthyroidism (specificity = 93.4%) and, above all, to exclude hypothyroidism (sensitivity = 35.3%) in our ambulatory patients. The delta-TSH values showed a basal TSH dependent linear increase (r = + 0.87, p < 0.001) both including only patients (n = 139) with basal TSH level in the euthyroidism range and including all patients (n = 223) having TSH responsive to TRH. All the patients with detectable basal TSH level displayed detectable TSH response to TRH, as did 19 (= 23.5%) of 81 patients with undetectable (< 0.1 microU/ml) basal value. In particular: a) for subnormal but detectable basal TSH ranging between 0.1 and 0.2 microU/ml, TSH was always hyporesponsive (delta-TSH < or = 2.5 microU/ml), while between 0.2 and 0.3 microU/ml TSH was hyporesponsive in 72.2% and normoresponsive (delta-TSH > 2.5 and < or = 11.9 microU/ml) in the remaining 27.8%; b) for basal TSH values within the normal range (0.3-3.2 microU/ml). TSH was hyporesponsive in 13.7%, normoresponsive in 74.8% and hyperresponsive in 11.5%; c) for high basal TSH values TSH was always hyperresponsive. The analysis of R TSH showed relatively constant values in the range of euthyroidism and hypothyroidism (m +/- SD: 7.4 +/- 2.3 and 7.7 +/- 3.1, respectively), and a marked differentiation of hyperthyroid patients whose R-TSH values were significantly lower (4.2 +/- 3.4) but had a wide individual variability. Linear regression analysis of basal or stimulated TSH and circulating thyroid hormones showed a close negative relationship, being highly significant between delta-TSH and T4 (r = 0.57, p < 0.001) and delta-TSH and FT4 (r = 0.46, p < 0.001). In conclusion, after the introduction of current second generation TSH immunoradiometric assay, the diagnostic role of the TRH test is greatly limited but not to be excluded: it can provide additional information to that obtained with simple basal TSH measurement in the diagnosis of subclinical hypothyroidism and in the precise evaluation of the degree of TSH suppression in patients with a subnormal basal TSH, either for endogenous thyrotoxicosis or I.-thyroxine treatment.  相似文献   
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Cellular communication and the transfer of information from one cell to another is crucial for cell viability and homeostasis. During the last decade, tunneling nanotubes (TNTs) have attracted scientific attention, not only as a means of direct intercellular communication, but also as a possible system to transport biological cargo between distant cells. Peculiar TNT characteristics make them both able to increase cellular survival capacities, as well as a potential target of neurodegenerative disease progression. Despite TNT formation having been documented in a number of cell types, the exact mechanisms triggering their formation are still not completely known. In this review, we will summarize and highlight those studies focusing on TNT formation in the nervous system, as well as their role in neurodegenerative diseases. Moreover, we aim to stress some possible mechanisms and important proteins probably involved in TNT formation in the nervous system.  相似文献   
6.
The transmembrane protein 106B (TMEM106B) gene is a susceptibility factor and disease modifier of frontotemporal dementia, but few studies have investigated its role in amyotrophic lateral sclerosis. The aim of this work was to assess the impact of the TMEM106B rs1990622 (A–major risk allele; G–minor allele) on phenotypic variability of 865 patients with amyotrophic lateral sclerosis. Demographic and clinical features were compared according to genotypes by additive, dominant, and recessive genetic models. Bulbar onset was overrepresented among carriers of the AA risk genotype, together with enhanced upper motor neuron involvement and poorer functional status in patients harboring at least one major risk allele (A). In a subset of 195 patients, we found that the homozygotes for the minor allele (GG) showed lower scores at the Edinburgh Cognitive and Behavioral Amyotrophic Lateral Sclerosis Screen, indicating a more severe cognitive impairment, mainly involving the amyotrophic lateral sclerosis-specific cognitive functions and memory. Moreover, lower motor neuron burden predominated among patients with at least one minor allele (G). Overall, we found that TMEM106B is a disease modifier of amyotrophic lateral sclerosis, whose phenotypic effects encompass both sites of onset and functional status (major risk allele), motor functions (both major risk and minor alleles), and cognition (minor allele).  相似文献   
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In the present paper a sheet of material is considered. It is loaded by uniaxial tensile stress and contains a random distribution of flaw orientations, with the flaws thought of as flat pre-cracks of comparable length, and with all crack planes being oriented perpendicular to the faces of the sheet. Intuition suggests that the most likely flaw to initiate fracture, which will be termed the “most dangerous defect”, lies orthogonally to the major load axis. The purpose of the present paper is to show that such an assumption is incorrect. Neither the most dangerous defect nor the first increments of crack growth will be oriented perpendicularly to the stress direction (nor will they be co-planar with the orientation of the most critical flaw).  相似文献   
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In Manufacturing-to-Order or Engineering-to-Order systems producing complex and highly customised items, each item has its own characteristics that are often tailored for a specific customer. Project scheduling approaches are suitable for production planning in such environments. However, when we consider the production of complex items, the distinct production operations are often aggregated into activities representing whole production phases. In such cases, the planning and scheduling problem works on the aggregate activities, considering that, in most cases, such activities also have to be manually executed. Moreover, simple finish-to-start precedence relations no longer correctly represent the real production process, but overlapping among activities should be allowed. In this paper, a project scheduling approach is proposed for production planning in Manufacturing-to-Order systems. The Variable Intensity formulation is used to allow the effort committed to the execution of activities to vary over time. Feeding precedences are developed to model generalised precedence relations when the execution mode of activities is not known a priori. Two mathematical formulations of these precedence relations are proposed. The formulations are applied both to randomly generated instances and to an industrial system producing machining centres and are compared in terms of computational efficiency.  相似文献   
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