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排序方式: 共有825条查询结果,搜索用时 15 毫秒
121.
122.
Valentina Cacciola Isabel Ferran Batllò Paola Ferraretto Simone Vincenzi Emilio Celotti 《European Food Research and Technology》2013,236(2):311-317
This work focused on the study of ultrasound (US) treatment effects on wine lees, in order to verify the possibility of accelerating the protective colloids (i.e., polysaccharides) release. Moreover, these effects were compared with the usual practices of aging wine over lees and with the enzyme treatment of lees by means of beta-glucanases able to demolish the glucans and facilitate the release of intracellular components. This work was performed considering the possibility of setting up a technology applicable in a cellar. Ultrasound treatment on wine lees resulted in an increase in total colloids, proteins, and polysaccharides in the medium with a reduction in the colloids particle diameter. These results were mainly correlated with treatment duration rather than its intensity. Treatment at 90 % amplitude for 3 min provided good enough results in terms of colloids release, and therefore, it was used for the comparative study with natural lysis and enzyme treatment. The parameters evaluated showed that the ultrasound treatment resulted in an increased release of colloids from yeast (polysaccharides and glycoproteins); therefore, a significant effect on the extraction of cellular components compared to the long stay on the lees was detected, indicating the interesting advantage that this new technological application can bring to the winemaking process. 相似文献
123.
Roberto Moreno Soriano Nuria Rojas Emilio Nieto Rosa de Guadalupe González-Huerta Juan Manuel Sandoval-Pineda 《International Journal of Hydrogen Energy》2021,46(51):25944-25953
To keep optimally connected, all electrolysis cell elements is one of the most important design criteria. The optimal distribution of the clamping points is crucial to increasing cell performance. In this work, the compression pressure distribution inside of a 25 cm2 PEM electrolysis cell was evaluated, using different materials: Teflon®, Viton®, ethylene propylene diene monomer rubber (EPDM), and nitrile rubber. Sealing material evaluation was performed taking as performance indicators: total compressed area (%) and compression pressure, for different torques applied. Pressure distribution was obtained by using pressure-sensitive films, analyzing the distribution of pressure points from three-dimensional plots (3D), and quantifying intensities of the images obtained. Results showed that pressure points distribution depends on the stiffness and thickness of the gasket materials. For a tightening torque of 3.70 N m, a pressure of 2.23 MPa is obtained with 85% of the membrane area compressed using nitrile rubber-EPDM gaskets. 相似文献
124.
Orduna-Malea Enrique Martín-Martín Alberto Thelwall Mike Delgado López-Cózar Emilio 《Scientometrics》2017,110(1):443-479
Scientometrics - Technology is a complex system with technologies relating to each other in a space that can be mapped as a network. The technology network’s structure can reveal properties... 相似文献
125.
Muthuri Robert Capecchi Sara Sulis Emilio Amantea Ilaria Angela Boella Guido 《Information Systems and E-Business Management》2022,20(1):27-55
Information Systems and e-Business Management - Companies need to be able to demonstrate compliance with rules and regulations, especially start-ups who typically do not have the legal expertise to... 相似文献
126.
The aim of this study was to investigate the functional consequences in vivo of adapting the rat exocrine pancreas to different dietary fats. Weanling rats were fed diets containing 10 wt% virgin olive
oil or sunflower oil for 8 wk. We then examined resting and cholecystokinin-octapeptide (CCK-8)-stimulated pancreatic secretion
in the anesthetized animals. To confirm a direct influence of the type of fat upon the gland, the FA composition of pancreatic
membranes as well as tissue protein and amylase content were determined in separate rats. The membrane FA profile was profoundly
altered by the diets, reflecting the type of dietary fat given, although this was not paralleled by variations in the pancreatic
content of protein or amylase. Nevertheless, dietary intake of oils evoked different effects on in vivo secretory activity. Resting flow rate and amylase output were significantly (P<0.05) enhanced by sunflower oil feeding. Time course changes in response to CCK-8 infusion also showed a different pattern
in each group. Secretion of fluid, protein, and amylase increased markedly in all animals, reaching a maximum within 20–40
min of infusion that was followed by a dramatic decline in both groups. In the sunflower oil group, this resulted in values
reaching the resting level as soon as 60 min after CCK-8 infusion was begun. However, after the initial decline, olive oil
group values showed a prolonged plateau elevation above the baseline (P<0.05) that was maintained for at least the infusion time. In addition, a positive correlation between flow rate and both
protein concentration and amylase activity existed in the olive oil group, but not in the sunflower oil group. The precise
mechanism by which these effects are produced remains to be elucidated. 相似文献
127.
Pablo Hernndez‐Alonso Nerea Becerra‐Toms Christopher Papandreou Mnica Bull Marta Guasch‐Ferr Estefanía Toledo Miguel Ruiz‐Canela Clary B. Clish Dolores Corella Courtney Dennis Amy Deik Dong D. Wang Cristina Razquin Jean‐Philippe Drouin‐Chartier Ramon Estruch Emilio Ros Montserrat Fit Fernando Ars Miquel Fiol Lluís Serra‐Majem Liming Liang Miguel A Martínez‐Gonzlez Frank B Hu Jordi Salas‐Salvad 《Molecular nutrition & food research》2020,64(12)
128.
This paper presents the CFD modeling methodology and validation for steady-state, normal operation in a PWR fuel assembly. This work is part of a program that is developing a CFD methodology for modeling and predicting single-phase and two-phase flow conditions downstream of structural grids that have mixing devices. The purpose of the mixing devices (mixing vanes in this case) is to increase turbulence and improve heat transfer characteristics of the fuel assembly. The detailed CFD modeling methodology for single-phase flow conditions in PWR fuel assemblies was developed using the STAR-CD CFD code. This methodology includes the details of the computational mesh, the turbulence model used, and the boundary conditions applied to the model. The methodology was developed by benchmarking CFD results versus small-scale experiments. The experiments use PIV to measure the lateral flow field downstream of the grid, and thermal testing to determine the heat transfer characteristics of the rods downstream of the grid. The CFD results and experimental data presented in the paper provide validation of the single-phase flow modeling methodology. Two-phase flow CFD models are being developed to investigate two-phase conditions in PWR fuel assemblies, and these can be presented at a future CFD Workshop. 相似文献
129.
Yukie Tanaka Kyaw Thu Aung Mitsuaki Ono Akihiro Mikai Anh Tuan Dang Emilio Satoshi Hara Ikue Tosa Kei Ishibashi Aya Ono-Kimura Kumiko Nawachi Takuo Kuboki Toshitaka Oohashi 《International journal of molecular sciences》2021,22(23)
Medication-related osteonecrosis of the jaw (MRONJ) is related to impaired bone healing conditions in the maxillomandibular bone region as a complication of bisphosphonate intake. Although there are several hypotheses for the onset of MRONJ symptoms, one of the possible causes is the inhibition of bone turnover and blood supply leading to bone necrosis. The optimal treatment strategy for MRONJ has not been established either. BMP-2, a member of the TGF-β superfamily, is well known for regulating bone remodeling and homeostasis prenatally and postnatally. Therefore, the objectives of this study were to evaluate whether cyclophosphamide/zoledronate (CY/ZA) induces necrosis of the bone surrounding the tooth extraction socket, and to examine the therapeutic potential of BMP-2 in combination with the hard osteoinductive biomaterial, β-tricalcium phosphate (β-TCP), in the prevention and treatment of alveolar bone loss around the tooth extraction socket in MRONJ-like mice models. First, CY/ZA was intraperitoneally administered for three weeks, and alveolar bone necrosis was evaluated before and after tooth extraction. Next, the effect of BMP-2/β-TCP was investigated in both MRONJ-like prevention and treatment models. In the prevention model, CY/ZA was continuously administered for four weeks after BMP-2/β-TCP transplantation. In the treatment model, CY/ZA administration was suspended after transplantation of BMP-2/β-TCP. The results showed that CY/ZA induced a significant decrease in the number of empty lacunae, a sign of bone necrosis, in the alveolar bone around the tooth extraction socket after tooth extraction. Histological analysis showed a significant decrease in the necrotic alveolar bone around tooth extraction sockets in the BMP-2/β-TCP transplantation group compared to the non-transplanted control group in both MRONJ-like prevention and treatment models. However, bone mineral density, determined by micro-CT analysis, was significantly higher in the BMP-2/β-TCP transplanted group than in the control group in the prevention model only. These results clarified that alveolar bone necrosis around tooth extraction sockets can be induced after surgical intervention under CY/ZA administration. In addition, transplantation of BMP-2/β-TCP reduced the necrotic alveolar bone around the tooth extraction socket. Therefore, a combination of BMP-2/β-TCP could be an alternative approach for both prevention and treatment of MRONJ-like symptoms. 相似文献
130.
Sandra Sendra Emilio Granell Jaime Lloret Joel J. P. C. Rodrigues 《Mobile Networks and Applications》2014,19(3):287-302
Official statistics data show that in many countries the population is aging. In addition, there are several illnesses and disabilities that also affect a small sector of the population. In recent years, researchers and medical foundations are working in order to develop systems based on new technologies and enhance the quality of life of them. One of the cheapest ways is to take advantage of the features provided by the smartphones. Nowadays, the development of reduced size smartphones, but with high processing capacity, has increased dramatically. We can take profit of the sensors placed in smartphones in order to monitor disabled and elderly people. In this paper, we propose a smart collaborative system based on the sensors embedded in mobile devices, which permit us to monitor the status of a person based on what is happening in the environment, but comparing and taking decisions based on what is happening to its neighbors. The proposed protocol for the mobile ad hoc network and the smart system algorithm are described in detail. We provide some measurements showing the decisions taken for several common cases and we also show the performance of our proposal when there is a medium size group of disabled or elderly people. Our proposal can also be applied to take care of children in several situations. 相似文献