A conservative and monotone mixed-hybridized finite element approximation of transport problems in heterogeneous domains

In this article, we discuss the numerical approximation of transport phenomena occurring at material interfaces between physical subdomains with heterogenous properties. The model in each subdomain consists of a partial differential equation with diffusive, convective and reactive terms, the coupling between each subdomain being realized through an interface transmission condition of Robin type. The numerical approximation of the problem in the two-dimensional case is carried out through a dual mixed-hybridized finite element method with numerical quadrature of the mass flux matrix. The resulting method is a conservative finite volume scheme over triangular grids, for which a discrete maximum principle is proved under the assumption that the mesh is of Delaunay type in the interior of the domain and of weakly acute type along the domain external boundary and internal interface. The stability, accuracy and robustness of the proposed method are validated on several numerical examples motivated by applications in biology, electrophysiology and neuroelectronics.     

Effects of driving mode and optimal material selection on a residence times difference-based fluxgate magnetometer

In this paper, analytical and experimental results on fluxgate magnetometers, intended to sense dc magnetic field, that make use of a readout technique based on the estimation of the residence times in the stable attractors are presented. The approach, exploiting the inherent nonlinear character of the bistable core dynamics, is based on the time-domain characterization of the transitions between the two saturation states of the hysteresis loop that is inherent in the ferromagnetic core dynamics. This readout technique affords the possibility of low amplitude and frequency reference (or bias) driving signals (sinusoidal or triangular), compared to conventional fluxgates, thereby reducing the device power requirements. The efficacy of this strategy is shown through an analytical approach, and via experimental results that suggest guidelines for the optimal design of the device. Considerations of the effects of a suitable choice of the magnetic core (in terms of its hysteresis behavior) have also been included. Experiments, carried out on miniaturized laboratory fluxgate prototypes with different ferromagnetic materials, reveal good performances of the proposed methodology, including suitable sensitivity and resolution, as well as low cost.     

Isolation of the [3H]gabapentin-binding protein/alpha 2 delta Ca2+ channel subunit from porcine brain: development of a radioligand binding assay for alpha 2 delta subunits using [3H]leucine

Mutations in a number of genes affect eye colour in Drosophila melanogaster; some of these "eye-colour" genes have been shown to be involved in various aspects of cellular transport processes. In addition, combinations of viable mutant alleles of some of these genes, such as carnation (car) combined with either light (lt) or deep-orange (dor) mutants, show lethal interactions. Recently, dor was shown to be homologous to the yeast gene PEP3 (VPS18), which is known to be involved in intracellular trafficking. We have undertaken to extend our earlier work on the lt gene, in order to examine in more detail its expression pattern and to characterize its gene product via sequencing of a cloned cDNA. The gene appears to be expressed at relatively high levels in all stages and tissues examined, and shows strong homology to VPS41, a gene involved in cellular-protein trafficking in yeast and higher eukaryotes. Further genetic experiments also point to a role for lt in transport processes: we describe lethal interactions between viable alleles of lt and dor, as well as phenotypic interactions (reductions in eye pigment) between allels of lt and another eye-colour gene, garnet (g), whose gene product has close homology to a subunit of the human adaptor complex, AP-3.     

Subretinal semiconductor microphotodiode array

OBJECTIVE: To evaluate the predictive validity of the Emergency Physician Job Satisfaction (EPJS) and Global Job Satisfaction (GJS) instruments. METHODS: Prospective mail survey of 223 Canadian emergency physicians (EPs) using a 42-item questionnaire, including 14 items evaluating their reasons for leaving emergency medicine (EM). Original (1990) EPJS and GJS scores were analyzed using 1-way ANOVA and Scheffe's test comparing the physicians who left EM with those still in their original jobs, and those who had left their original jobs but who stayed in EM. Mean scores on the 14 "reason for leaving" items were compared with scores from an earlier sample of U.S. physicians using a t-test for independent means. Criteria for statistical significance were set at alpha = 0.05 for all analyses. RESULTS: The response rate for the primary study questions was 99.1%. Of the respondents, 29.4% had left their original jobs, and 10.4% had left EM altogether. The GJS scores for the physicians who left EM were significantly different from those for the physicians who stayed (p = 0.004). The EPJS scores for the physicians who left EM were not significantly different from those for the physicians who stayed (p = 0.56). There was no significant difference in scores between the Canadian and U.S. physicians' reasons for leaving EM (all p-values > 0.05). Shiftwork scored the highest as a reason to leave EM. CONCLUSIONS: A low GJS score is associated with physicians' leaving EM, but not with changing jobs. The EPJS instrument was not associated with either outcome. Canadian and U.S. EPs place similar levels of importance on potential reasons for leaving EM.     

Bispecific antibodies overcome the opsonin-receptor mismatch of cystic fibrosis in vitro: restoration of neutrophil-mediated phagocytosis and killing of Pseudomonas aeruginosa

Inflammation and infection associated with bacterial pathogens, primarily Pseudomonas aeruginosa (Pa), are the primary causes of morbidity and mortality for cystic fibrosis (CF) patients. CF patients may be predisposed to these bacterial infections by a defect in phagocytosis due to "opsonin-receptor mismatch," in which a complement receptor (CR1) and an important opsonin (iC3b) are destroyed by proteolytic enzymes. We show that opsonin-receptor mismatch can be mitigated in vitro using a bispecific Ab (bsAb) to cross-link neutrophils via the beta-chain of leukocyte integrins (CD18) to bacterial epitopes or C3d on opsonized Pa. Two chemically cross-linked bsAb were constructed with mAb specific for C3d (or the O-specific side chain of Fisher Devlin Immunotype 1 Pa) and CD18. Using an in vitro model of elastase-mediated opsonin-receptor mismatch, these bsAb specifically enhanced Pa phagocytosis and killing, with the anti-C3d-containing bsAb restoring the levels of phagocytosis to approximately those for the non-elastase-treated opsonic control. These results encourage the further investigation of bsAb as therapeutic agents for bacterial infection in the lungs of CF patients.     

Reducing violence and prejudice in a Jamaican all age school using attachment and mentalization theory.

A study is reported of a psychoanalytic intervention in a very violent and prejudiced Jamaican school with disenfranchised children 7–9 grades who had failed academic streaming examinations. Over the period of 3 years of the intervention using mentalization and power issues approaches grounded in attachment theory, children were assisted to feel connected and valued by their school. There were striking improvements in academic performance, decreased victimization, and increased helpfulness especially in boys including significant trickle down effects to grades 1–6. Overall, the school became a place teachers wanted to join and the Jamaican government recognized their success and built a new school for them in a better location. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Carotid artery occlusion due to bacterial paranasal sinusitis

BACKGROUND: Many experts have suggested that blunt splenic trauma in patients older than 55 years should not be managed by observation because of supposed increased fragility of the spleen and decreased physiologic reserve in elderly patients. We sought to determine the outcome of nonoperative management of blunt splenic trauma in patients older than 55 years. METHODS: For the years 1994 through 1996, data for patients with splenic injury older than 55 years from seven trauma centers in a single state were reviewed. RESULTS: Blunt splenic trauma occurred in 41 patients older than 55 years. Eight patients were excluded from further analysis because of death from massive associated injuries within 24 hours of admission. The remaining 33 patients (mean age, 72+/-10 years) were divided into two groups: immediate exploration (10 patients) and observation (23 patients). Observation of blunt splenic injury failed in 4 of 23 patients (17%). No patient deaths were related to the method of management of the splenic injury. CONCLUSIONS: Observation of the elderly patient with blunt splenic trauma has an acceptable failure rate of 17%.     

Discrimination between Southern Italy and foreign milk samples using spectroscopic and analytical data

Determination of the geographical origin of foodstuffs is becoming of increasing interest to consumers and producers, since it may be used as a criterion for certifying quality, authenticity and typicality.