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51.
In patients with early-stage endocrine receptor-positive (ER+) breast cancer (BC), adjuvant endocrine therapy (ET) for 5 years is the standard of care. However, for some patients, the risk of recurrence remain high for up to 15 years after diagnosis and extended ET beyond 5 years may be a reasonable option. Nevertheless, this strategy significantly increases the occurrence of side effects. Here we summarize the available evidence from randomized clinical trials on the efficacy and safety profile of extended ET and discuss available clinical and genomic tools helpful to select eligible patients in daily clinical practice.  相似文献   
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A parametric model, giving the solar direct irradiance at the ground, using as input parameters the precipitable water vapour and the optical thickness of particulate matter is presented. The validity of the parametrization is tested against a spectral model checked during field studies.  相似文献   
54.
Effects of Nonplastic Fines on the Liquefaction Resistance of Sands   总被引:5,自引:0,他引:5  
A laboratory parametric study utilizing cyclic triaxial tests was performed to clarify the effects of nonplastic fines on the liquefaction susceptibility of sands. Studies previously published in the literature have reported what appear to be conflicting results as to the effects of silt content on the liquefaction susceptibility of sandy soils. The current study has shown that if the soil structure is composed of silt particles contained within a sand matrix, the resistance to liquefaction of the soil is controlled by the relative density of the soil and is independent of the silt content of the soil. For soils whose structure is composed of sand particles suspended within a silt matrix, the resistance to liquefaction is again controlled by the relative density of the soil, but is lower than for soils with sand-dominated matrices at similar relative densities. In this case, the resistance to liquefaction is essentially independent of the amount and type of sand. These findings suggest the need for further evaluation of the effects of nonplastic fines content upon penetration resistance, and the manner in which this relationship affects the simplified methods currently used in engineering practice to evaluate the liquefaction resistance of silty soils.  相似文献   
55.
Water loss is an issue that affect Water Distribution Systems (WDSs) very often, especially when aged and high pressure occurs. Pressure reduction valves (PRVs) can be used as devices to reduce as much as possible the water losses within the network. Indeed, for a given number of PRVs, the daily volume of water lost from the network can be reduced minimizing the pressure through a proper choice of valve positions as well as their settings. In this paper, a methodology for the optimal number, positioning and setting of PRVs is presented. In the proposed methodology, a genetic algorithm is coupled with a physical modelling of leakage from joints and a simplified and yet realistic hydraulic simulation of the WDS. The proposed methodology is demonstrated using two WDSs examples. Comparisons with a more extreme and complicated hydraulic modelling, already proposed by authors in previous work, are also performed in the first case study in order to validate the proposed methodology. These comparisons demonstrate that the methodology proposed in this work performs fairly well when compared to similar approach that uses a more sophisticated hydraulic model. As a consequence, it revealed to be a good tool for the optimal positioning and sizing of PRVs within WDS aimed at reducing the background leakages even when the WDS is characterized by complex geometry and topology.  相似文献   
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The zona pellucida (ZP) is an extracellular membrane surrounding mammalian oocytes. The so-called zona hardening plays a key role in fertilization process, as it blocks polyspermy, which may also be caused by an increase in the mechanical stiffness of the ZP membrane. However, structural reorganization mechanisms leading to ZP''s biomechanical hardening are not fully understood yet. Furthermore, a correct estimate of the elastic properties of the ZP is still lacking. Therefore, the aim of the present study was to investigate the biomechanical behaviour of ZP membranes extracted from mature and fertilized bovine oocytes to better understand the mechanisms involved in the structural reorganization of the ZP that may lead to the biomechanical hardening of the ZP. For that purpose, a hybrid procedure is developed by combining atomic force microscopy nanoindentation measurements, nonlinear finite element analysis and nonlinear optimization. The proposed approach allows us to determine the biomechanical properties of the ZP more realistically than the classical analysis based on Hertz''s contact theory, as it accounts for the nonlinearity of finite indentation process, hyperelastic behaviour and material heterogeneity. Experimental results show the presence of significant biomechanical hardening induced by the fertilization process. By comparing various hyperelastic constitutive models, it is found that the Arruda–Boyce eight-chain model best describes the biomechanical response of the ZP. Fertilization leads to an increase in the degree of heterogeneity of membrane elastic properties. The Young modulus changes sharply within a superficial layer whose thickness is related to the characteristic distance between cross-links in the ZP filamentous network. These findings support the hypothesis that biomechanical hardening of bovine ZP is caused by an increase in the number of inter-filaments cross-links whose density should be higher in the ZP inner side.  相似文献   
58.
Faridur is the first ‘soft kernel’ durum wheat variety released in Italy. This variety has not yet been evaluated for its end-use quality. In the present study, the milling performance (using two different mills) and bread-making ability of Faridur were compared with Svevo. An effect of the mill type on flour properties was observed, with the Chopin CD1 mill leading to finer particle size, higher starch damage and water absorption than Bühler MLU 202. Protein and gluten content was significantly higher in Faridur, but gluten quality was lower, as indicated by alveograph and farinograph analyses. The softer nature of Faridur facilitated milling, reducing energy consumption and starch damage. The baking test led to a compact product, with low specific volume, needing adjustments in processing and formulation. As energy saving has become a key competitive factor in the milling sector, Faridur has potential for expanding the use of durum wheat.  相似文献   
59.
Dry fractionation was applied to the legume-based pasta (yellow lentils:whole rice 90:10 w:w) discarded for physical defects. After the air classification, the fine fraction showed a 33% increment of the protein content compared to the raw material, with a 21% yield. The scanning electron micrographs revealed the presence of protein–starch complexes and broken starch granules which led to a low protein separation efficiency. The fine fraction showed interesting nutritional features due to the high concentration of the essential micronutrients Zn (43.3 mg kg−1) and Fe (72.6 mg kg−1). However, also the alpha-galactosides were enriched into the same fraction. The two fractions, fine and coarse, were both characterised by elevated water absorption capacity, with significantly higher values in the fine one. Finally, the gelling capacity varied among the fractions, being influenced by the protein content. Overall, these ingredients could be used to fortify the protein and the essential mineral contents of bakery products, sauces, and creams.  相似文献   
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