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141.
Alpha-1-antitrypsin (AAT) and fibrinogen are secretory acute phase reactant proteins. Circulating AAT and fibrinogen are synthesized exclusively in the liver. Mutations in the encoding genes result in conformational abnormalities of the two molecules that aggregate within the rough endoplasmic reticulum (RER) instead of being regularly exported. That results in AAT-deficiency (AATD) and in hereditary hypofibrinogenemia with hepatic storage (HHHS). The association of plasma deficiency and liver storage identifies a new group of pathologies: endoplasmic reticulum storage disease (ERSD).  相似文献   
142.
The high amount of computer resources required to simulate complex free surface flows has prompted for developing fractional step schemes capable of reducing the computational effort. These schemes are borrowed from a wider family of methods originally devised for the incompressible Navier-Stokes equations. An alternative approach is to perform an algebraic splitting on the coefficient matrix of the linear system resulting from the discretized problem, ending up with the successive solution of sub-problems of smaller size. The resulting schemes are shown in different cases to be the algebraic counterpart of the standard fractional step formulations. This algebraic procedure was again originally devised in the context of incompressible Navier-Stokes system, but we believe it is far more general: in this paper it is indeed extended to the more involved 3D free surface flow model. The inexact block factorization technique is applied to the coefficient matrix arising from the problem at hand and two significant choices for the approximation are discussed and numerically tested.  相似文献   
143.
This paper presents a procedure for the identification of imperfections of structural parameters based on displacement measurements by static tests. The proposed procedure is based on the well‐known Hu–Washizu variational principle, suitably modified to account for the response measurements, which is able to provide closed‐form solutions to some inverse problems for the identification of structural parameter imperfections in beams. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
144.
The moral acts of 19 dyads of 4-yr-olds in a cognitively simplified version of Prisoner's Dilemma game were analyzed in relationship to their friendship, emotions, and processes of conflict resolution. Degree of friendship was rated by teachers; 2 sociologists used a Q-sort of group processes to describe the dyads' interactions. The emotions of each S were coded from videotape independently of his/her partner's and with the sound turned off. Moral acts were categorically identified as equalization, reparation, stalemate, default, and betrayal. These acts were also assigned scale scores on a dimension of moral sensitivity that was independently derived from separate work with 143 undergraduates, who judged the 5 acts in all possible paired comparisons and then rated the moral difference between each pair. These data almost perfectly fitted a model of increasing monotonic function. The degree of friendship between the dyads and their interactive processes—group orientation, positive emotional tone, and active involvement—were positively related to sensitive moral action. Their emotions were related to concurrent acts, and more importantly, predicted their subsequent acts even though they seldom talked about morality. Results suggest that if social scientists' search for practical morality is to be successful, emotional communication needs to be considered. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
145.
Carbon based structures have been widely studied by X-ray absorption (XAS), also called NEXAFS, which is a very useful bulk probing method that allows examining the unoccupied density of states (DOS) and the site selective bonding environment. Two very well known spectral features in the XAS core level spectrum are the σ* and π* bands, and both have been analyzed in several studies for graphitic-like systems. However, among all the carbon materials, the unique one-dimensional electronic properties attributed to single-walled carbon nanotubes (SWCNTs) exhibit features that reveal clearly their electronic structure in the core level XAS spectrum. In this article, we outline the C1s response in XAS, which is related to the DOS of the conduction band in SWCNTs and its fine structure, revealed by experiments performed on metallicity-sorted SWCNT material. The progress in the identification of changes in the site selective conduction band electronic structure with XAS is discussed in detail.  相似文献   
146.
The secondary structure of legume (Phaseolus vulgaris L. and Lens culinaris L.) proteins was investigated by studying the amide I infrared absorption band in whole seed flours, before and after dry heating and autoclaving thermal treatments. The analysis procedure, set up on 7S and different model proteins, shows that the content of β-sheet structures in lentil is higher than in common bean (47% vs. 32%). The dry heating does not appreciably affect secondary structures in lentil, while it causes a reduction of β-sheets (to 13%), an increase of aggregates, and the appearance of random coil structures in common bean. The autoclaving treatment produces high amounts of aggregates in both legumes. However, in lentil, random coil structures are lower than in common bean and some β-sheet structures are still detectable. These results indicate that multimeric heat-induced complexes of legume proteins have a high stability because of the high content in β-sheet structures, in particular in lentil, which may adversely affect protein utilization.  相似文献   
147.
The spatiotemporal analysis of a region's precipitation climate regime could be particularly interesting for many fields of applied sciences, such as climatology, hydrology and water resources management. In this study, the precipitation trends at seasonal and annual scale, over a large area of the northern Hemisphere have been analysed based on a globally gridded precipitation data sets of monthly observations. In particular, among the several data sets available in literature, with spatial resolutions of 0.5° longitude/latitude, in this work the Global Precipitation Climatology Centre Full Data Reanalysis Version 6 data set has been used. The broad extension of the area under investigation allowed a better understanding of trend precipitation patterns over space. In fact, yearly results evidenced a marked negative rainfall tendency in the eastern Mediterranean (more than ?20 mm/10 years) and in North Africa (until ?16 mm/10 years), while a relatively large positive trend (more than 20 mm/10 years) in central and northern Europe has been observed.  相似文献   
148.
Steven–Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are severe adverse drug reactions, characterized by extensive epidermal detachment and erosions of mucous membrane. SJS/TEN is one of the most serious adverse reactions to Nevirapine (NVP) treatment, commonly used in developing countries as first-line treatment of human immunodeficiency virus infection. In the last years TRAF3IP2 gene variants had been described as associated with susceptibility to several diseases such as psoriasis and psoriatic arthritis. We hypothesized that this gene, involved in immune response and in NF-κB activation, could also be implicated in the SJS/TEN susceptibility. We performed a full resequencing of TRAF3IP2 gene in a population of patients treated with NVP. Twenty-seven patients with NVP-induced SJS/TEN and 78 controls, all from Mozambique, were enrolled. We identified eight exonic and three intronic already described variants. The case/control association analysis highlighted an association between the rs76228616 SNP in exon 2 and the SJS/TEN susceptibility. In particular, the variant allele (C) resulted significantly associated with a higher risk to develop SJS/TEN (p = 0.012 and OR = 3.65 (95% CI 1.33–10.01)). A multivariate analysis by logistic regression confirmed its significant contribution (p = 0.027, OR = 4.39 (95% CI 1.19–16.23)). In conclusion, our study suggests that a variant in TRAF3IP2 gene could be involved in susceptibility to SJS/TEN.  相似文献   
149.
Basal cell carcinoma (BCC) is the most common cancer in individuals with fair skin type (I–II) and steadily increasing in incidence (70% of skin malignancy). It is locally invasive but metastasis is usually very rare, with an estimated incidence of 0.0028%–0.55%. Conventional therapy is surgery, especially for the H region of the face and infiltrative lesions; in case of inoperable tumors, radiotherapy is a valid option. Recently, topical photodynamic therapy (PDT) has become an effective treatment in the management of superficial and small nodular BCC. PDT is a minimally invasive procedure that involves the administration of a photo-sensibilizing agent followed by irradiation at a pre-defined wavelength; this determines the creation of reactive oxygen species that specifically destroy target cells. The only major side effect is pain, reported by some patients during the irradiation. The high cure rate and excellent cosmetic outcome requires considering this possibility for the management of patients with both sporadic and hereditary BCC. In this article, an extensive review of the recent literature was made, in order to clarify the role of PDT as a possible alternative therapeutic option in the treatment of BCC.  相似文献   
150.
In this work, we use a multifluid model to investigate numerically the dynamics of segregating fluidized bidisperse mixtures. The model uses the default multifluid equations of commercial computational fluid dynamics (CFD) codes, except for the fluid–particle drag force closure, which Mazzei and Lettieri [1] recently developed and extended to polydisperse systems. The study also comprises some preliminary simulations of collapsing monodisperse beds, focusing on the role of the plastic solid stress. This work tests whether the model is able to correctly predict not only the axial segregation profiles through the bed, but also the minimum fluid velocities at which a) the mixture, being no longer fixed, starts segregating and transient fluidization takes place, and b) the mixture becomes steadily fluidized and fully mixed. To validate the model predictions, we use the experimental findings of Marzocchella et al. [2]. The plastic stress results to play an important role, rendering the simulations more stable and allowing for larger time steps. The model well predicts the stationary axial segregation profiles, and for short computational times estimates correctly the onset of transient fluidization; for longer computational times, however, the system evolves towards a new steady state where, even if the powder is at maximum packing, it partly segregates. The model overestimates the velocity required to fully mix the suspension, probably because the simulated bubbling is not as vigorous as it is experimentally.  相似文献   
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