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91.
Simplified Approach for the Seismic Response of a Pile Foundation   总被引:1,自引:0,他引:1  
Pseudostatic approaches for the seismic analysis of pile foundations are attractive for practicing engineers because they are simple when compared to difficult and more complex dynamic analyses. To evaluate the internal response of piles subjected to earthquake loading, a simplified approach based on the “p-y” subgrade reaction method has been developed. The method involves two main steps: first, a site response analysis is carried out to obtain the free-field ground displacements along the pile. Next, a static load analysis is carried out for the pile, subjected to the computed free-field ground displacements and the static loading at the pile head. A pseudostatic push over analysis is adopted to simulate the behavior of piles subjected to both lateral soil movements and static loadings at the pile head. The single pile or the pile group interact with the surrounding soil by means of hyperbolic p-y curves. The solution derived first for the single pile, was extended to the case of a pile group by empirical multipliers, which account for reduced resistance and stiffness due to pile-soil-pile interaction. Numerical results obtained by the proposed simplified approach were compared with experimental and numerical results reported in literature. It has been shown that this procedure can be used successfully for determining the response of a pile foundation to “inertial” loading caused by the lateral forces imposed on the superstructure and “kinematic” loading caused by the ground movements developed during an earthquake.  相似文献   
92.
Traumatic brain injury (TBI) frequently affects both the basic and the superordinate components of attention; deficits vary according to patient age. This study evaluated the efficacy of a specific remediation intervention for attention. Sixty-five TBI patients (aged 6?18 years) with attention deficit were assessed at baseline and at 1-year follow-up: 40 patients received attention-specific neuropsychological training for 6 months, and the control group comprised 25 patients. Cognitive assessment included a Wechsler Intelligence Scale (e.g., A. Orsini, 1993) and the Continuous Performance Test II (CPT II; C. K. Conners, 2000). The Vineland Adaptive Behavior Scales (VABS; S. Sparrow, D. Balla & D. V. Cicchetti, 1984) was administered to assess the treatment's ecological validity. At baseline, all patients presented with a mild intellectual disability and pathological scores on the CPT II. At follow-up, significant differences were found between the 2 groups on the CPT II and VABS: The clinical group improved more than the control group. Specific remediation training for attention, including a combination of a process-specific approach and metacognitive strategies, significantly improved attention performance. Improvement in attention skills also affected adaptive skills positively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
Radon (222Rn) concentration was evaluated in shops of the Savona Province, Italy, between summer 2002 and winter 2002-2003. The main characteristics of each shops were recorded through a questionnaire investigating the ventilation rate and factors related to 222Rn precursors in the soil and the construction materials. The main variables that were related to radon concentration were the following: age of the building, level of the shop above ground, season of the year, wind exposure, active windows, and type of heating system. Shops equipped with individual air heating/conditioning systems exhibited radon concentrations that were three times higher than those of shops heated by centralized furnaces. Our data indicate that the level of pollution in the shops was of medium level, with an expected low impact on the salespersons' health. Only in wintertime, the action level of 200 Bq m(-3) for the confined environment was reached in 10 shops equipped with individual air heating/conditioning systems.  相似文献   
94.
The skin is the largest organ of the human body, serving as an effective mechanical barrier between the internal milieu and the external environment. The skin is widely considered the first-line defence of the body, with an essential function in rejecting pathogens and preventing mechanical, chemical, and physical damages. Keratinocytes are the predominant cells of the outer skin layer, the epidermis, which acts as a mechanical and water-permeability barrier. The epidermis is a permanently renewed tissue where undifferentiated keratinocytes located at the basal layer proliferate and migrate to the overlying layers. During this migration process, keratinocytes undertake a differentiation program known as keratinization process. Dysregulation of this differentiation process can result in a series of skin disorders. In this context, aquaporins (AQPs), a family of membrane channel proteins allowing the movement of water and small neutral solutes, are emerging as important players in skin physiology and skin diseases. Here, we review the role of AQPs in skin keratinization, hydration, keratinocytes proliferation, water retention, barrier repair, wound healing, and immune response activation. We also discuss the dysregulated involvement of AQPs in some common inflammatory dermatological diseases characterised by skin barrier disruption.  相似文献   
95.
In this work, a performing LC method with evaporative light-scattering detector was described for the analysis of tartaric, malic, ascorbic, citric and succinic acids in fruit juices. The method was optimized and validated in comparison with LC-UV, in terms of accuracy, LODs, LOQs and precision. The successive application to ACE, orange, pear, peach, mulberry and apple juices allowed separation and quantitative determination of organic acids in about 20 min just diluting and filtering the sample before LC determination. In the analysed juices, citric, malic and ascorbic acids were always present, and in all the samples, citric acid was the prevailing acid followed by malic acid except for peach and apple juices where an opposite trend was found. Tartaric and succinic acids were detected at lower concentrations and more rarely, except for peach juices, all containing tartaric acid, and ACE and orange juices, all containing succinic acid.  相似文献   
96.
Recent biotechnological applications in the field of clinical oncology led to the identification of new biomarkers as molecular targets of cancer, and to broad developments in the field of personalized medicine. Aptamers are oligonucleotides (ssDNA or RNA) that are selected to specifically recognize a molecular target with high affinity and specificity. Based on this, new horizons for their use as molecular imaging probes are being explored. The objective of this work was to evaluate the Sgc8-c aptamer conjugated with Alexa Fluor 647 fluorophore as an imaging probe in a colon tumor xenograft mouse model, with potential application in molecular imaging. In this study, the LS174T cell line was used to induce colorectal adenocarcinoma in nude mice. After confirmation of PTK7 overexpression by immunohistochemistry, in vivo studies were performed. Pharmacokinetic, in vivo and ex vivo biodistribution imaging, and a competition assay were evaluated by fluorescence imaging. In vivo visualization of the probe in the tumors was assessed two hours after aptamer probe administration, exhibiting excellent tumor-to-background ratios in biodistribution studies and high specificity in the competition test. Our results demonstrated the functionality of Scg8-c as an imaging probe for colon cancer, with potential clinical applications.  相似文献   
97.
We consider a thermodynamic consistent microscale model from for the transport processes of lithium ion concentration and charge in lithium ion batteries. A fully convergent finite element discretisation in space of arbitrary order with uniform time stepping is discussed for this strongly nonlinear coupled system of nonlinear PDEs. We analyse the error for higher order finite element methods on a representative geometry, which shows already the difficulties when dealing with a realistic microstructure. Moreover we derive explicit analytical formulas for the exact solutions for the elliptic subproblem and the complete time-dependent problem for a non-trivial geometry. These results show the need for appropriate boundary approximations as well as adaptive refinement strategies. In addition we incorporate a two-phase intercalation model for the electrode. This moving boundary model, also called Stefan problem, has also been implemented. Simulations of our battery model including the two-phase model will be shown.  相似文献   
98.
Frataxin is a highly conserved protein whose deficiency results in the neurodegenerative disease Friederich’s ataxia. Frataxin’s actual physiological function has been debated for a long time without reaching a general agreement; however, it is commonly accepted that the protein is involved in the biosynthetic iron-sulphur cluster (ISC) machinery, and several authors have pointed out that it also participates in iron homeostasis. In this work, we use site-directed spin labeling coupled to electron paramagnetic resonance (SDSL EPR) to add new information on the effects of ferric and ferrous iron binding on the properties of human frataxin in vitro. Using SDSL EPR and relating the results to fluorescence experiments commonly performed to study iron binding to FXN, we produced evidence that ferric iron causes reversible aggregation without preferred interfaces in a concentration-dependent fashion, starting at relatively low concentrations (micromolar range), whereas ferrous iron binds without inducing aggregation. Moreover, our experiments show that the ferrous binding does not lead to changes of protein conformation. The data reported in this study reveal that the currently reported binding stoichiometries should be taken with caution. The use of a spin label resistant to reduction, as well as the comparison of the binding effect of Fe2+ in wild type and in the pathological D122Y variant of frataxin, allowed us to characterize the Fe2+ binding properties of different protein sites and highlight the effect of the D122Y substitution on the surrounding residues. We suggest that both Fe2+ and Fe3+ might play a relevant role in the context of the proposed FXN physiological functions.  相似文献   
99.
Silicon-boron alloys have been recently pointed out as novel ultra-high temperature phase change materials for applications in Latent Heat Thermal Energy S  相似文献   
100.
Pacetti  T.  Castelli  G.  Bresci  E.  Caporali  E. 《Water Resources Management》2020,34(14):4527-4544
Water Resources Management - Water-related Ecosystem Services (WES), namely the multiple benefits that humans can obtain from water or water-related functions of an ecosystem, constitute a useful...  相似文献   
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