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排序方式: 共有399条查询结果,搜索用时 15 毫秒
71.
This work aims to explore the applicability of electrical resistance tomography (ERT) in the analysis of fluid distribution in haemodialysis modules, which is not straightforward due to the complex geometry of the hollow fibre bundles and the small sizes of the modules. On the other hand, ERT is potentially a suitable and convenient technique for investigation in this field due to its cost-effectiveness and capacity to perform measurements in opaque systems. After a preliminary estimation of the fibre bundle local distribution, the assessment of the technique is performed by observing the time evolution of the measured conductivity maps during the module filling and emptying operations with water and air, which are alternatively fed inside or outside the fibre bundle. Reliable conductivity maps are obtained by placing the module vertically or horizontally. Additional experimental data collected by feeding liquid mixtures of different sodium chloride concentrations show that the technique is suitable for detecting concentration variations, due to the mass transfer through the fibres, and flow maldistribution, due to the specific geometry of the module. From the preliminary results collected in this work, the technique appears to be adequate for the collection of data that can support the optimization of the module geometry and computational model validation. 相似文献
72.
Alessandro Lucidi Danilo Buca Carlo Ronsini Sara Tinari Giuseppina Bologna Davide Buca Martina Leombroni Marco Liberati Francesco DAntonio Giovanni Scambia Paola Lanuti Marco Petrillo 《International journal of molecular sciences》2020,21(22)
Extracellular vesicles (EVs) are a heterogeneous group of cell-derived submicron vesicles released under physiological or pathological conditions. EVs mediate the cellular crosstalk, thus contributing to defining the tumor microenvironment, including in epithelial ovarian cancer (EOC). The available literature investigating the role of EVs in EOC has been reviewed following PRISMA guidelines, focusing on the role of EVs in early disease diagnosis, metastatic spread, and the development of chemoresistance in EOC. Data were identified from searches of Medline, Current Contents, PubMed, and from references in relevant articles from 2010 to 1 April 2020. The research yielded 194 results. Of these, a total of 36 papers, 9 reviews, and 27 original types of research were retained and analyzed. The literature findings demonstrate that a panel of EV-derived circulating miRNAs may be useful for early diagnosis of EOC. Furthermore, it appears clear that EVs are involved in mediating two crucial processes for metastatic and chemoresistance development: the epithelial–mesenchymal transition, and tumor escape from the immune system response. Further studies, more focused on in vivo evidence, are urgently needed to clarify the role of EV assessment in the clinical management of EOC patients. 相似文献
73.
Giuseppina Luzzi Marco Steffens Ingrid Clawin‐Rdecker Wolfgang Hoffmann Charles M A P Franz Jan Fritsche Peter Chr Lorenzen 《International Journal of Dairy Technology》2020,73(3):502-512
Lactose solutions of up to 50% (w/v) were incubated with lactases and glucose isomerases for subsequent implementation in dairy product samples to enhance sweetness. A degree of hydrolysis of >90% and of isomerisation of 50% were attainable. The sensory sweetening power of lactose in solutions of up to 50% (w/v) can be enhanced 2–3 times. Based on sensory experiments, application of this bi‐enzymatic system in yoghurt and pudding samples allowed for a 10–20% (w/w) reduction in the total sugar content, whilst retaining equal sweetness. The growth of yoghurt starter cultures was not affected, yet furosine formation more than doubled in high heated, enzyme‐modified milk. 相似文献
74.
Adriano do Nascimento Simões Samara Lopes de Almeida Cristine Vanz Borges Kelem Silva Fonseca Aurélio Paes Barros Júnior José Ricardo Tavares de Albuquerque Camila Renata Corrêa Igor Otavio Minatel Maria Aparecida dos Santos Morais Marla Silvia Diamante Giuseppina Pace Pereira Lima 《Journal of Food Biochemistry》2020,44(8):e13322
75.
Natalia Brossard Beatriz Gonzalez-Muñoz Carolina Pavez Arianna Ricci Xinmiao Wang Fernando Osorio Edmundo Bordeu Giuseppina Paola Parpinello Jianshe Chen 《International Journal of Food Science & Technology》2021,56(10):5382-5394
Astringency is a sensory attribute, related to the quality and mouthfeel of red wines. However, the origin of astringency sub-qualities, such as the typical drying astringency found in immature grapes, is still unknown. Astringency of red wines with similar tannin content but different astringency sub-qualities, from different harvest dates, is studied. Astringency was characterised in terms of friction coefficient, polyphenol content, sensory analysis and tannin/salivary–proteins aggregates characterisation. A different evolution during ripening was found for both Cabernet Sauvignon and Carménère, and tannin–protein aggregates showed differences in size, shape and surface. The velvety sub-quality appears to be related to aggregates with low precipitation, and with specific surface characteristics as roundness and Feret diameter. Results from this work propose an effect of aggregates on sensory perception and opens the possibility to explore their effect on oral lubrication. 相似文献
76.
Experimental results are interpreted in terms of a simple lumped-element model that is also used to reproduce the hysteresis phenomenon with discrete components. The hysteresis is related to a three-dimensional (3-D) nonuniformity in the current distribution. Such hysteresis can lead to an erroneous evaluation of latchup parameters, such as the holding current density 相似文献
77.
This paper presents the results of measurements performed on test structures implementing circuits for controlled erase of floating gate MOSFET's. The obtained results show that, with cells fabricated using standard technology, the obtained performance is sufficiently good to allow use in analog applications. The circuit has been demonstrated to be robust with respect to variations of the programming pulse characteristics and to partially compensate cell aging effects on the threshold window. This latter feature is particularly interesting for digital applications because it allows the reduction of the window margin, thus improving memory endurance 相似文献
78.
C Giardina G Renzulli G Serio DM Caniglia T Lettini C Ferri G D'Eredità R Ricco VP Delfino 《Canadian Metallurgical Quarterly》1996,18(5):374-382
OBJECTIVE: To determine whether nuclear morphometry can confirm or add useful information to classic clinicopathological prognosticators to identify the subpopulation of breast carcinoma patients with node-negative (N-) disease, at high risk of disease relapse. STUDY DESIGN: On the basis of results obtained by clinicopathologic evaluation of a group of patients with N- breast cancer, on a test group of 56 cases (32 patients disease free and 24 with relapse), we performed a morphometric analytical study of nuclei using the Shape Analytical Morphometry (SAM) software system; 20 nuclei for each case and 17 morphometric parameters for each nucleus were analyzed. RESULTS: The SAM system allowed us to quantify shape differences in nuclei in terms of contour irregularities and asymmetries along with evaluation of nuclear dimensions. Dimensional and analytic parameters were subjected to univariate (Student's t test) and multivariate (Hotelling's test) analysis. Multivariate discriminant analysis showed that an exact forecast of disease relapse could be made in 77% of patients with N- breast cancer by using a set of six both analytic and dimensional parameters. CONCLUSION: These results confirm that nuclear pleomorphism is the result of both contour irregularities and shape asymmetries and that even though they should be considered preliminary results, they stress the importance of quantitative shape evaluation. 相似文献
79.
Giuseppina Ambrogio Claudio Ciancio Luigino Filice Francesco Gagliardi 《International Journal of Material Forming》2017,10(3):279-286
The use of metamodelling techniques in process design has become indispensable to perform faster solutions reducing time to market. This approach allows the implementation of decision support tools which are easier to use than the conventional numerical simulations. In this paper, a robust metamodelling technique has been designed and its feasibility has been validated for the crucial problem of localised thinning in sheet metal forming process. The proposed methodology is based on the innovative integration between the Design of Experimental statistical method and the Kriging one. This approach, in fact, allows to analyse contemporary the continuous and categorical factors and, as a consequence, to define a single tool for changing process conditions (i.e., material and product shape). To test the reliability of the mathematical approach, the same was performed for the case study of Incremental Sheet Forming, a process strongly affected by the not homogeneous distribution of the thickness. Taking advantage of this strategy, a wide experimental investigation has been performed to build the base of knowledge of the problem both for the metamodelling design and for the validation of the decision support tool; moreover, the experimental data were utilized to set and validate a numerical model, which was subsequently used to enrich the dataset. The proposed metamodel, suitably modified according to each process peculiarities, can be generally adapted for sheet thickness prediction. 相似文献
80.