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91.
Raimund Bürger Ricardo Ruiz Kai Schneider Mauricio A. Sepúlveda 《Journal of Engineering Mathematics》2008,60(3-4):365-385
A fully adaptive finite volume multiresolution scheme for one-dimensional strongly degenerate parabolic equations with discontinuous
flux is presented. The numerical scheme is based on a finite volume discretization using the Engquist–Osher approximation
for the flux and explicit time-stepping. An adaptive multiresolution scheme with cell averages is then used to speed up CPU
time and meet memory requirements. A particular feature of our scheme is the storage of the multiresolution representation
of the solution in a dynamic graded tree, for the sake of data compression and to facilitate navigation. Applications to traffic
flow with driver reaction and a clarifier–thickener model illustrate the efficiency of this method. 相似文献
92.
93.
A Fernández Fernández R Franco Manzano M Fernández Ruíz G Otero Mauricio 《Canadian Metallurgical Quarterly》1997,21(1):72-74
Severe protein deprivation at weaning provokes an arrest of cellular proliferation and maturation, and an increase of ADA and PNP activities in the thymus of growing rats. A 20% casein diet fed during 9 days was enough to reverse the effect on ADA and PNP. The supplementation with 24 mg/d of n-3 PUFA, was able to recover thymus' cellular proliferation and maturation. 相似文献
94.
Pelham Brett W.; Carvallo Mauricio; DeHart Tracy; Jones John T. 《Canadian Metallurgical Quarterly》2003,85(5):800
B. W. Pelham, M. C. Mirenberg, and J. T. Jones (see record 2002-12744-001) argued that most people prefer stimuli that are associated with the self, a preference they called implicit egotism. In support of implicit egotism, Pelham et al presented evidence from 10 archival studies showing that people gravitate toward careers and places of residence that resemble their names or birthday numbers. M. Gallucci (see record 2003-09138-001) argued that alternate analyses of the same data provide strong evidence against implicit egotism. Whereas Gallucci was correct that Pelham et al's original analyses were flawed, their results remain significant even when more conservative tests are used. The authors also present new data in support of implicit egotism, including exhaustive studies of (a) common surnames and US city names and (b) common surnames and street names. The new studies also revealed that as sample sizes grow larger, studies are more likely to produce evidence of implicit egotism. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Stephen J Wilson Michael A Sayette Mauricio R Delgado Julie A Fiez 《Nicotine & tobacco research》2005,7(4):637-645
In recent years, research applying functional neuroimaging to the study of cue-elicited drug craving has emerged. This research has begun to identify a distributed system of brain activity during drug craving. A review of this literature suggested that expectations regarding the opportunity to use a drug affected the pattern of neural responses elicited by drug cues. Using functional magnetic resonance imaging (fMRI), we examined the effects of smoking expectancy on the neural response to neutral (e.g., roll of tape) and smoking-related (a cigarette) stimuli in male cigarette smokers deprived of nicotine for 8 hr. As predicted, several brain regions (e.g., the anterior cingulate cortex) exhibited differential activation during cigarette versus neutral cue exposure. Moreover, we found that subregions of the prefrontal cortex (i.e., ventromedial, ventrolateral, and dorsolateral prefrontal cortices) showed cue-elicited activation that was modulated by smoking expectancy. These results highlight the importance of perceived drug use opportunity in the neurobiological response to drug cues. 相似文献
96.
Bentosela Mariana; Ruetti Eliana; Muzio Rubén N.; Mustaca Alba E.; Papini Mauricio R. 《Canadian Metallurgical Quarterly》2006,120(2):371
Rats given access to a 32% sucrose solution and then downshifted to a 4% solution exhibit less contact with the sipper tube than unshifted controls always given access to 4% solution. This phenomenon, called consummatory successive negative contrast, was facilitated in Experiment 1 by a posttrial injection of corticosterone (3 mg/kg) administered immediately after the first downshift trial. Experiment 2 demonstrated that this facilitatory effect of posttrial corticosterone does not occur when administered 3 hr after the first downshift trial. These results support the hypothesis that corticosterone strengthens an aversive emotional component elicited by the surprising downshift in reward magnitude during the initial downshift trial. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Graphene: Large‐Area Si‐Doped Graphene: Controllable Synthesis and Enhanced Molecular Sensing (Adv. Mater. 45/2014) 下载免费PDF全文
98.
99.
Mauricio CL Martins MM Ramos EV Souza-Santos D 《Radiation protection dosimetry》2011,144(1-4):130-136
Instituto de Radioprote??o e Dosimetria, a Brazilian government research institute, provides individual monitoring services since 1972. Its dosemeters are: film-based thorax for whole body photons, thermoluminescence dosimetry (TLD) albedo for whole body neutrons and TLD ring for extremity photons. About 6000 radiation workers are currently being monitored with film dosemeters in 256 different facilities in Brazil, most of them working in health-related activities. Around 400 Brazilian radiation workers are monitored with TLD albedo neutron monitor and about 500 workers use TLD rings. This paper describes the monitoring systems used, presents the results obtained in internal quality programs and in intercomparison exercises and analyses the measured dose values from 1985 to 2009. 相似文献
100.
Garcia-Rudaz C Dorfman M Nagalla S Svechnikov K Söder O Ojeda SR Dissen GA 《Reproduction (Cambridge, England)》2011,142(2):319-331
Excessive nerve growth factor (NGF) production by the ovary, achieved via a transgenic approach, results in arrested antral follicle growth, reduced ovulatory capacity, and a predisposition to cyst formation in response to mildly elevated LH levels. Two salient features in these mutant mice (termed 17NF) are an elevated production of 17α-hydroxyprogesterone (17-OHP(4)), testosterone, and estradiol (E(2)) in response to gonadotropins, and an increased frequency of granulosa cell (GC) apoptosis. In this study, we show that the increase in steroidal response is associated with enhanced expression of Cyp17a1, Hsd17b, and Cyp19a1, which encode the enzymes catalyzing the synthesis of 17-OHP(4), testosterone, and E(2) respectively. Using a proteomic approach, we identified stathmin (STMN1), as a protein that is overproduced in 17NF ovaries. In its phosphorylated state, STMN1 mediates a cell death signal initiated by tumor necrosis factor α (TNF). STMN1 is expressed in GCs and excessive NGF increases its abundance as well as that of its forms phosphorylated at serine (Ser) 16, 25, and 38. TNF synthesis is also increased in 17NF ovaries, and this change is abolished by blocking neurotrophic tyrosine kinase receptors. Inhibiting TNF actions in vivo by administering a soluble TNF receptor prevented the increase in total and phosphorylated STMN1 production, as well as GC apoptosis in NGF-overproducing ovaries. These results indicate that an excess of NGF in the ovary promotes steroidogenesis by enhancing the expression of enzyme genes involved in 17-OHP(4), testosterone, and E(2) synthesis, and causes GC apoptosis by activating a TNF/ STMN1-mediated cell death pathway. 相似文献