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11.
An effective reliability-based procedure is presented to assess the capability of hospitals to be functional after a seismic event of a given intensity. Every major function in a hospital depends on the joint action of various cooperating services, which in turn are made up from a certain number of sub-services. Such a complex organization is described in terms of a logical scheme and subsequently reduced to a minimal cut-set representation. For each sub-service a collapse criterion is defined, by which the strength is compared to the action load, both represented as random variables. Strengths are evaluated through assessment analyses based on design drawings. Loads are evaluated from 3-D linear dynamic analyses under seismic input. This is given by the Eurocode 8 elastic response spectrum, scaled at a given peak ground acceleration and account for the position of the sub-service within the building. By calculating the failure probability of each service by FORM (First Order Reliability Method) or SORM (Second Order Reliability Methods), the probability of functional interruption is obtained in terms of Didevsen bounds, conditional on a given earthquake intensity. The method helps to single out weak elements and potential sources of damage (structural, non-structural, equipment) within the hospital. This allows: (a) to investigate quantitatively the effectiveness of different upgrading criteria, (b) to select rationally intervention hypotheses, both in the retrofitting and rehabilitation of existing hospitals and in the design optimization of new ones, and (c) to evaluate different investment options for seismic vulnerability mitigation. As an example, an application to a case study hospital is presented.  相似文献   
12.
48 males participated in an aggression task after receiving either alcoholic or placebo beverages and after being told that they had received either a high or a low dose of alcohol. All Ss in the alcohol group actually received the same dose. Measures of aggression were the intensity and duration of shock given to a bogus partner in a RT-pain perception task and a score on a posttask attitude questionnaire. Blood alcohol readings were taken 3 times during the session, and a locus of control scale was administered before and after drinking. For Ss in the alcohol conditions, blood alcohol levels averaged .079% before the task and .085% afterwards. Alcohol resulted in higher aggression scores only on the questionnaire measure, and an interaction between drug and attribution was found for the measure of shock duration. Attribution alone resulted in greater aggression on the measure of shock intensity. Ss in groups where the attribution was discrepant with the drug condition were the most aggressive on the measures of shock intensity and duration. These Ss became more external, reflecting a high correlation between their aggression and a stimulus tone. Results suggest that a person's increased aggressiveness when intoxicated results from an interaction between alcohol and an altered responsivity to provoking stimuli. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
13.
CHROMagar Salmonella (CAS), a new chromogenic medium, was retrospectively compared to Hektoen enteric agar (HEA) with 501 Salmonella stock isolates and was then prospectively compared to HEA for the detection and presumptive identification of Salmonella spp. with 508 stool samples before and after enrichment. All stock cultures (100%), including cultures of H2S-negative isolates, yielded typical mauve colonies on CAS, while 497 (99%) isolates produced typical lactose-negative, black-centered colonies on HEA. Following overnight incubation at 37 degreesC, a total of 20 Salmonella strains were isolated from the 508 clinical samples. Sensitivities for primary plating and after enrichment were 95% (19 isolates) and 100% (20 isolates), respectively, for CAS and 80% (16 isolates) and 100% (20 isolates), respectively, for HEA. The specificity of CAS (88.9%) was significantly higher than that of HEA (78.5%; P < 0.0001). On the basis of its good sensitivity and specificity, CAS medium can be recommended for use for primary plating when human stool samples are screened for Salmonella spp.  相似文献   
14.
    
In the past four decades numerous findings have indicated that gap junction channel gating is mediated by intracellular calcium concentrations ([Ca2+i]) in the high nanomolar range via calmodulin (CaM). We have proposed a CaM-based gating model based on evidence for a direct CaM role in gating. This model is based on the following: CaM inhibitors and the inhibition of CaM expression to prevent chemical gating. A CaM mutant with higher Ca2+ sensitivity greatly increases gating sensitivity. CaM co-localizes with connexins. Connexins have high-affinity CaM-binding sites. Connexin mutants paired to wild type connexins have a higher gating sensitivity, which is eliminated by the inhibition of CaM expression. Repeated trans-junctional voltage (Vj) pulses progressively close channels by the chemical/slow gate (CaM’s N-lobe). At the single channel level, the gate closes and opens slowly with on-off fluctuations. Internally perfused crayfish axons lose gating competency but recover it by the addition of Ca-CaM to the internal perfusion solution. X-ray diffraction data demonstrate that isolated gap junctions are gated at the cytoplasmic end by a particle of the size of a CaM lobe. We have proposed two types of CaM-driven gating: “Ca-CaM-Cork” and “CaM-Cork”. In the first, the gating involves Ca2+-induced CaM activation. In the second, the gating occurs without a [Ca2+]i rise.  相似文献   
15.
    
Current research on dental implants has mainly focused on the influence of surface roughness on the rate of osseointegration, while studies on the development of surfaces to also improve the interaction of peri-implant soft tissues are lacking. To this end, the first purpose of this study was to evaluate the response of human gingival fibroblasts (hGDFs) to titanium implant discs (Implacil De Bortoli, Brazil) having different micro and nano-topography: machined (Ti-M) versus sandblasted/double-etched (Ti-S). The secondary aim was to investigate the effect of the macrogeometry of the discs on cells: linear-like (Ti-L) versus wave-like (Ti-W) surfaces. The atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis showed that the Ti-S surfaces were characterized by a significantly higher micro and nano roughness and showed the 3D macrotopography of Ti-L and Ti-W surfaces. For in vitro analyses, the hGDFs were seeded into titanium discs and analyzed at 1, 3, and 5 days for adhesion and morphology (SEM) viability and proliferation (Cck-8 and MTT assays). The results showed that all tested surfaces were not cytotoxic for the hGDFs, rather the nano-micro and macro topography favored their proliferation in a time-dependent manner. Especially, at 3 and 5 days, the number of cells on Ti-L was higher than on other surfaces, including Ti-W surfaces. In conclusion, although further studies are needed, our in vitro data proved that the use of implant discs with Ti-S surfaces promotes the adhesion and proliferation of gingival fibroblasts, suggesting their use for in vivo applications.  相似文献   
16.
17.
Trypsin inhibitors of two varieties of Bauhinia variegata seeds have been isolated and characterized. Bauhinia variegata candida trypsin inhibitor (BvcTI) and B. variegata lilac trypsin inhibitor (BvlTI) are proteins with Mr of about 20,000 without free sulfhydryl groups. Amino acid analysis shows a high content of aspartic acid, glutamic acid, serine, and glycine, and a low content of histidine, tyrosine, methionine, and lysine in both inhibitors. Isoelectric focusing for both varieties detected three isoforms (pI 4.85, 5.00, and 5.15), which were resolved by HPLC procedure. The trypsin inhibitors show Ki values of 6.9 and 1.2 nM for BvcTI and BvlTI, respectively. The N-terminal sequences of the three trypsin inhibitor isoforms from both varieties of Bauhinia variegata and the complete amino acid sequence of B. variegata var. candida L. trypsin inhibitor isoform 3 (BvcTI-3) are presented. The sequences have been determined by automated Edman degradation of the reduced and carboxymethylated proteins of the peptides resulting from Staphylococcus aureus protease and trypsin digestion. BvcTI-3 is composed of 167 residues and has a calculated molecular mass of 18,529. Homology studies with other trypsin inhibitors show that BvcTI-3 belongs to the Kunitz family. The putative active site encompasses Arg (63)-Ile (64).  相似文献   
18.
The gene expression response of yeast to various types of stresses/perturbations shows a common functional and dynamical pattern for the vast majority of genes, characterised by a quick transient peak (affecting primarily short genes) followed by a return to the pre-stimulus level. Kinetically, this process of adaptation following the transient excursion can be modelled using a genome-wide autoregulatory mechanism by means of which yeast aims at maintaining a preferential concentration in its mRNA levels. The resulting feedback system explains well the different time constants observable in the transient response, while being in agreement with all the known experimental dynamical features. For example, it suggests that a very rapid transient can be induced also by a slowly varying concentration of the gene products.  相似文献   
19.
    
The phase-change memory (PCM) technology is considered as one of the most attractive non-volatile memory concepts for next generation data storage. It relies on the ability of a chalcogenide material belonging to the Ge-Sb-Te compound system to reversibly change its phase between two stable states, namely the poly-crystalline low-resistive state and the amorphous high-resistive state, allowing the storage of the logical bit. A careful study of the phase-change material properties in terms of the set operation performance, the program window and the electrical switching parameters as a function of composition is very attractive in order to enlarge the possible PCM application spectrum. Concerning the set performance, a crystallization kinetics based interpretation of the observed behavior measured on different Ge-Sb-Te compounds is provided, allowing a physics-based comprehension of the reset-to-set transition.  相似文献   
20.
Knowledge of the epidemiological pattern and the potential sources of infections is important to control Staphylococcus aureus in dairy herds. This paper reports the results of a study applying both pulse field gel electrophoresis (PGFE) and the assessment of a selected number of virulence genes to investigate the role of teat skin on Staph. aureus transmission among cows and on the contamination of milk. Overall 61 isolates were considered, 23 from teat skin, 33 from milk samples and 5 from curd samples. Teat swabs were taken in five herds, but in only three of them could Staph. aureus be isolated. Curd was sampled in three herds, but Staph. aureus could be isolated in only two herds. The distribution of isolates among herds confirmed the presence of herd-specific Staph. aureus strain in most of the herds. The same pattern was observed in teat skin samples, in quarter milk samples, and in the curd samples. Our findings are consistent with other studies showing the role of teat skin as a potential reservoir. Moreover, Staph. aureus was isolated from teat skin of confirmed Staph. aureus-negative cows that were segregated from infected ones. Our findings also suggest that some strains have higher chances to survive on teat skin and therefore to increase the risk for contamination of milk and milk products due to the persistence of intramammary infections.  相似文献   
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