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排序方式: 共有1324条查询结果,搜索用时 15 毫秒
61.
Chiara Bellocchi Angelica Carandina Beatrice Montinaro Elena Targetti Ludovico Furlan Gabriel Dias Rodrigues Eleonora Tobaldini Nicola Montano 《International journal of molecular sciences》2022,23(5)
The autonomic nervous system (ANS) and the immune system are deeply interrelated. The ANS regulates both innate and adaptive immunity through the sympathetic and parasympathetic branches, and an imbalance in this system can determine an altered inflammatory response as typically observed in chronic conditions such as systemic autoimmune diseases. Rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis all show a dysfunction of the ANS that is mutually related to the increase in inflammation and cardiovascular risk. Moreover, an interaction between ANS and the gut microbiota has direct effects on inflammation homeostasis. Recently vagal stimulation techniques have emerged as an unprecedented possibility to reduce ANS dysfunction, especially in chronic diseases characterized by pain and a decreased quality of life as well as in chronic inflammation. 相似文献
62.
André Dias Lukas Gorzelniak Rudolf A. Jörres Rainald Fischer Gunnar Hartvigsen Alexander Horsch 《Pervasive and Mobile Computing》2012,8(6):837-844
Physical Activity (PA) plays an important role in the health and quality of life of cystic fibrosis (CF) patients, but little is known about their PA in daily living. With the use of accelerometers it is now possible to monitor activity profiles in detail. The goals of this study are to assess feasibility and acceptance of a longer-term use of accelerometers in daily living in CF patients, study the possibility of detecting changes in PA in relation to the patients’ clinical state and compare the findings between a CF and an age-matched healthy control group. We asked 15 CF patients to wear two accelerometers for 21 days and fill in a diary. Ten of them (age 21 to 40, mean 29.5 years) participated and delivered data that could be evaluated. We also recruited 10 age-matched control subjects. Data was processed for calculating usage time and features extracted to construct models of activity. The younger patients, particularly females, were concerned with fashion and style and considered wearing the sensors a challenge. Overall, the compliance of patients with CF seemed to be lower than reported for elder subjects in the literature. Time-series analysis of the data indicated characteristic patterns of PA over time, provided that data pre-processing and noise-filtering had been optimized. Further studies have to assess whether the continuous recording of PA yields additional clinical information in CF and in particular, whether it is possible to detect or even predict exacerbations in patients with CF or other diseases. 相似文献
63.
A. Andrade‐Campos F. Teixeira‐Dias J. Grcio 《Materialwissenschaft und Werkstofftechnik》2005,36(10):566-571
The present work deals with the interdependences between the strain rate and the strain hardening on stainless austenitic steels. Uniaxial tension tests were conducted on a 304 stainless steel at different strain rates in order to analyse the influence of this parameter on the strain hardening and on the material formability. For the strain rates levels analysed (10‐4 to 10‐1 s‐1) it was also observed that increasing the strain rate from 10‐4 up to 10‐1 s‐1 leads to a 25 % difference in uniform tension elongation revealing the curve‐crossing phenomenon. Namely, strain rates equal or higher than 10‐2 lead to a stagnation of strain hardening after a tensile strain of about 0.2. In order to investigate the results obtained, microstructural and thermal analyses were conducted and numerical simulations were performed. It was observed that the decreasing of formability of the material is essentially due to thermal aspects. In the discussion, the experimental and numerical results are analysed in terms of thermal softening, phase transformation and strain rate sensibility. 相似文献
64.
Clemente Neves Sousa Paulo Teles Vanessa Filipa Ferreira Dias João Luís Alves Apóstolo Maria Henriqueta Jesus Silva Figueiredo Maria Manuela Martins 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(3):695-699
Vascular access is one of the leading causes of mobilization of financial resources in health systems for people with chronic kidney disease on hemodialysis. Physical examination of the arteriovenous fistula (AVF) has demonstrated its effectiveness in identifying complications. We decided to evaluate the influence of nurses' professional experience in the detection of complications of the AVF (venous stenosis and steal syndrome). The study took place in eight hemodialysis centers between May and September of 2011 in the north of Portugal. Sample was constituted by registered nurses. The nurses involved in the experiment were divided in two groups: those who had more than 5 years of experience and those who had less than 5 years of experience. Ninety‐two nurses participated in the study: 34 nurses had less than 5 years of professional experience and 58 had more than 5 years of professional experience. In the practices considered by nurses in the detection of venous stenosis, there were no differences observed between the groups (P > 0.05). In steal syndrome, there were no differences observed between the groups in the practices of the nurses in the detection of this complication of the AVF (P > 0.05). We concluded that professional experience does not influence the detection of venous stenosis and steal syndrome. 相似文献
65.
Maria M Marques Susete Fernandes Sandra G Correia Susana Caroo Pedro T Gomes Alberto R Dias Joo Mano Marvin D Rausch James C
W Chien 《Polymer International》2001,50(5):579-587
Vinyl acetate, methyl methacrylate, acrylonitrile and methyl vinyl ketone were investigated for co‐ and terpolymerization with ethylene and ethylene–propylene. Precursor [bis(N,N ′‐dimesitylimino)acenaphthene]dibromonickel, activated by methylaluminoxane was used as a catalyst system and trialkylaluminium was employed to block the polar groups for these polymerizations. Polymerization activities of the order of magnitude of 106 in the case of vinyl acetate and methyl methacrylate, and 105 in the case of acrylonitrile were achieved. Microanalysis and GPC of acrylonitrile copolymers found about 17 units of acrylonitrile per polymer chain. Copolymers with very different properties from the parent homopolymers were obtained in all cases except that of methyl vinyl ketone. © 2001 Society of Chemical Industry 相似文献
66.
67.
In this text we present the real-time implementation of a Bayesian framework for robotic multisensory perception on a graphics
processing unit (GPU) using the Compute Unified Device Architecture (CUDA). As an additional objective, we intend to show
the benefits of parallel computing for similar problems (i.e. probabilistic grid-based frameworks), and the user-friendly
nature of CUDA as a programming tool. Inspired by the study of biological systems, several Bayesian inference algorithms for
artificial perception have been proposed. Their high computational cost has been a prohibitory factor for real-time implementations.
However in some cases the bottleneck is in the large data structures involved, rather than the Bayesian inference per se.
We will demonstrate that the SIMD (single-instruction, multiple-data) features of GPUs provide a means for taking a complicated
framework of relatively simple and highly parallelisable algorithms operating on large data structures, which might take up
to several minutes of execution with a regular CPU implementation, and arrive at an implementation that executes in the order
of tenths of a second. The implemented multimodal perception module (including stereovision, binaural sensing and inertial
sensing) builds an egocentric representation of occupancy and local motion, the Bayesian Volumetric Map (BVM), based on which
gaze shift decisions are made to perform active exploration and reduce the entropy of the BVM. Experimental results show that
the real-time implementation successfully drives the robotic system to explore areas of the environment mapped with high uncertainty. 相似文献
68.
Minh-Tuan Pham Laurent Briançon Daniel Dias Abdelkader Abdelouhab 《Geotextiles and Geomembranes》2018,46(5):611-624
Geosynthetic-reinforced soils constitute an interesting solution for bridging cavities. Many methods have been developed to analyze the stability of soil-geosynthetic-cavity systems, but none of them is able to take into account all the complexities of these mechanisms. Many researchers have assumed mechanisms developed in the reinforced granular platform when cavities appear, such as load transfer and expansion of materials. However, they are not fully understood because many factors can influence the design, such as the cavity opening processes, the type, and the density of the soil.In this study, a new laboratory apparatus is developed to simulate two different cavity opening procedures (trapdoor and progressive opening) for different geometric configurations. A series of tests is conducted for three granular soils with two different geosynthetic sheets. By measuring the shape of the surface soil settlement and the geosynthetic deflection, the expansion coefficient is calculated. A novel tactile pressure sensor is used to observe the load transfer during the cavity opening. The experimental data are analyzed and the influence of the experimental conditions (geometric and soil properties and the opening procedure) are also discussed. Correspondingly, elicited findings can be used to propose recommendations to improve the existing design methods. 相似文献
69.
Juliana Alvarenga Alves Luiz Carlos de Oliveira Lima Disney Ribeiro Dias Cleiton Antônio Nunes Rosane Freitas Schwan 《International Journal of Food Science & Technology》2010,45(11):2358-2365
The aim of this study was to evaluate the contribution of yeast to the volatile profile of beverages obtained by the fermentation of lychee must through inoculated (Saccharomyces cerevisiae strains UFLA CA116 , UFLA CA1183 and UFLA CA1174 ) and spontaneous fermentation. Higher alcohols and esters were the primary volatiles detected by SPME/GC–MS. A Principal Component Analysis indicated similarities between UFLA CA116 and UFLA CA1183 and between UFLA CA1174 and spontaneous fermentation. Changing the yeast strain used in the fermentation process has the potential to modulate the volatile profile of fermented beverages. The beverage produced by the inoculation of yeast CA1183 showed the most complex aroma profile compared to the other beverages. 相似文献
70.
Janete Deliberali Freo Neiva Deliberali Rosso Lidiane Borges Dias de Moraes Álvaro Renato Guerra Dias Moacir Cardoso Elias Luiz Carlos Gutkoski 《Journal of Stored Products Research》2011,47(4):316-320
This study was done to evaluate the physicochemical properties and to quantify the residual silicon in flour from wheat grains treated with different dosages of DE and stored in a conventional system for 180 days. Samples containing 10.0 kg of wheat grain were treated with 0.00, 2.00 and 4.00 g kg−1 of DE and then homogenized and stored in cotton bags at 22 °C and 70 ± 5 g 100 g−1 relative humidity. Physicochemical analyses were carried out at 0, 60, 120 and 180 days of storage. The experiment was conducted in a randomized design with a factorial 3 × 4 arrangement (three doses of DE × four storage periods), totaling 12 treatments, with three replicates for each treatment. The wheat flour samples were digested and the silicon residue quantification was conducted through colorimetry. The wheat treated with DE presented a lower test weight compared with control, +b∗ chromaticity coordinate for color and increased ash content and L∗. The physicochemical changes in the grain and wheat flour were proportional to the amount of DE applied. 相似文献