997 resultados para Non-ideal Duffing
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The parasite that causes simian malaria in the Brazilian Amazon, Plasmodium brasilianum, is infective to man. In this region, where humans live within and in close proximity to the forest, it was suspected that this parasite could be the cause of a zoonosis. A study was performed in the areas surrounding two hydroelectric plants in the Amazon, Balbina and Samuel, aiming at determining the zoonotic potential of this parasite. P. brasilianum was detected in, respectively, 15.8% and 9.9% of 126 and 252 primates belonging to seven and eight species examined from Balbina and Samuel. The highest malaria infection rates were found among the red-howler monkey Alouatta seniculus straminea (32.3%), the bearded-saki Chiropotes satanas chiropotes (50%) and the spider-monkey Ateles paniscus paniscus (2[1+]) from Balbina and in the squirrel-monkey Saimiri ustus (21%) and the black-faced-spider-monkey Ateles paniscus chamek (28.6%) from Samuel.
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El proyecto de investigación desarrollado durante el período de la beca se inserta en el marco del proyecto de investigación titulado "Especialidad de formación, especialidad de empleo y resultados de inserción laboral" (ESFOREM). La primera línea de investigación desarrollada se centró en el análisis macroestadístico de la relación entre la formación y el empleo en el caso de los jóvenes españoles a partir del análisis estadísitico de los datos proporcionados por la Encuesta ETEFIL (INE, 2005). El propósito de la investigación era cotejar en qué medida los jóvenes con nivel educativo no universitario estaban trabajando de aquello para lo cual se habían formado específicamente según el Catálogo Nacional de Cualificaciones (adecuación normativa) y hasta qué punto la no correspondencia entre el empleo (según su nivel y especialidad) y la formación (según su nivel y especialidad) suponía una fracaso respecto a su inserción laboral. Enfoques dominantes sobre la relación entre formación y empleo parten del supuesto normativo de que la correspondencia entre especialidad de formación y especialidad de empleo es la situación óptima y se postula que la dinámica del mercado de trabajo tiende a propiciarla. El proyecto ESFOREM tenía una segunda línea de investigación que planteaba un análisis cualitativo de dos subsectores específicos. Esta tesis doctoral se inserta en la segunda línea de investigación desarrollada y tiene como propósito analizar y explicar, mediante una estrategia de investigación cualitativa un caso específico de modalidad de relación en la que no existe correspondencia entre formación y empleo, de forma tal de poder analizar y explicar el papel activo que los agentes e instituciones tienen en la configuración de la relación. El caso seleccionado ha sido del "empleo de cuidado en domicilio depersonas en situación de dependencia", con el objetivo de contribuir a profundizar en el estudio de un sector de empleo que es cada vez más emergente y que está fuertemente feminizado. Dicho estudio se realiza a nivel comparado y municipal entre Montevideo y Barcelona.
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Quel type de recherche empirique peut, voire doit, produire un clinicien qui ne veut pas céder à une épistémologie réaliste ? Quelques "guideslines" dégagés pour conduire des recherches qui soient utiles à la psychologie et à la psychiatrie cliniques. Le regard d'un systémicien critique.
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Introduction : L'ostéoporose et/ou les fractures liées à la grossesse sont souvent sous-diagnostiquées. Nous rapportons 2 cas de fractures diagnostiquées peu après l'accouchement de 2èmes grossesses. Patientes. Cas 1. Patiente de 30 ans présentant des dorso-lombalgies à la fin de sa 2ème grossesse. Une IRM après l'accouchement montre 2 fractures vertébrales (L1 et L2). Densité minérale osseuse (DMO): T-score colonne: -3.9 DS, col fémoral -1.7 DS et hanche totale -0.6 DS. Cas 2. Patiente de 32 ans, présentant des douleurs fessières à la fin de sa 2ème grossesse. L'IRM pelvienne après l'accouchement montre une fracture de l'aile sacrée droite S1-S3 et de l'aile sacrée gauche S1.DMO: T-score colonne -1.4 DS, col fémoral 0.2 DS et hanche totale 0.0 DS. La microarchitecture est normale (TBS 1.429). Nous retenons dans le 1er cas le diagnostic d'une ostéoporose fracturaire liée à la grossesse. De l'ibandronate trimestriel iv est prescrit. Dans le 2ème cas, au vu de la DMO quasi normale, de la trabéculométrie normale et du site atypique de la fracture, nous concluons à une fracture non ostéoporotique sur augmentation du stress mécanique lié à la grossesse. Aucun traitement à visée osseuse n'est prescrit. Discussion : " L'ostéoporose " liée à la grossesse et à l'allaitement se manifeste le plus souvent par des fractures vertébrales non traumatiques pendant le 3ème trimestre de la 1ère grossesse ou durant le post-partum. Une DMO et un bilan à la recherche d'une cause secondaire sont indispensables. Cette pathologie est sous-diagnostiquée, car les douleurs dorsolombaires sont souvent mises sur le compte d'une hyperlaxité ligamentaire physiologique liée aux hormones. Les facteurs de risque sont les mêmes que pour une ostéoporose post-ménopausique. Les apports bas en calcium et en vitamine D3 ainsi qu'un capital osseux moindre à la fin de l'adolescence seraient des facteurs prédisposants. La DMO lombaire diminue de 7.6 +/-0.1%, celle du corps entier de 3.9 +/-0.1% pendant la grossesse et l'allaitement. Habituellement on assiste à une récupération de la DMO dans les mois qui suivent la fin de l'allaitement. Conclusion : Devant des douleurs rachidiennes en fin de grossesse il faut évoquer une fracture ostéoporotique liée à la grossesse. La densitométrie osseuse peut aider au diagnostic même s'il faut l'interpréter prudemment dans les mois qui suivent l'accouchement. Il n'y a pas de consensus concernant le traitement spécifique.
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This article presents a feasibility study with the objective of investigating the potential of multi-detector computed tomography (MDCT) to estimate the bone age and sex of deceased persons. To obtain virtual skeletons, the bodies of 22 deceased persons with known age at death were scanned by MDCT using a special protocol that consisted of high-resolution imaging of the skull, shoulder girdle (including the upper half of the humeri), the symphysis pubis and the upper halves of the femora. Bone and soft-tissue reconstructions were performed in two and three dimensions. The resulting data were investigated by three anthropologists with different professional experience. Sex was determined by investigating three-dimensional models of the skull and pelvis. As a basic orientation for the age estimation, the complex method according to Nemeskéri and co-workers was applied. The final estimation was effected using additional parameters like the state of dentition, degeneration of the spine, etc., which where chosen individually by the three observers according to their experience. The results of the study show that the estimation of sex and age is possible by the use of MDCT. Virtual skeletons present an ideal collection for anthropological studies, because they are obtained in a non-invasive way and can be investigated ad infinitum.
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An African oxalogenic tree, the iroko tree (Milicia excelsa), has the property to enhance carbonate precipitation in tropical oxisols, where such accumulations are not expected due to the acidic conditions in these types of soils. This uncommon process is linked to the oxalate-carbonate pathway, which increases soil pH through oxalate oxidation. In order to investigate the oxalate-carbonate pathway in the iroko system, fluxes of matter have been identified, described, and evaluated from field to microscopic scales. In the first centimeters of the soil profile, decaying of the organic matter allows the release of whewellite crystals, mainly due to the action of termites and saprophytic fungi. In addition, a concomitant flux of carbonate formed in wood tissues contributes to the carbonate flux and is identified as a direct consequence of wood feeding by termites. Nevertheless, calcite biomineralization of the tree is not a consequence of in situ oxalate consumption, but rather related to the oxalate oxidation inside the upper part of the soil. The consequence of this oxidation is the presence of carbonate ions in the soil solution pumped through the roots, leading to preferential mineralization of the roots and the trunk base. An ideal scenario for the iroko biomineralization and soil carbonate accumulation starts with oxalatization: as the iroko tree grows, the organic matter flux to the soil constitutes the litter, and an oxalate pool is formed on the forest ground. Then, wood rotting agents (mainly termites, saprophytic fungi, and bacteria) release significant amounts of oxalate crystals from decaying plant tissues. In addition, some of these agents are themselves producers of oxalate (e.g. fungi). Both processes contribute to a soil pool of "available" oxalate crystals. Oxalate consumption by oxalotrophic bacteria can then start. Carbonate and calcium ions present in the soil solution represent the end products of the oxalate-carbonate pathway. The solution is pumped through the roots, leading to carbonate precipitation. The main pools of carbon are clearly identified as the organic matter (the tree and its organic products), the oxalate crystals, and the various carbonate features. A functional model based on field observations and diagenetic investigations with δ13C signatures of the various compartments involved in the local carbon cycle is proposed. It suggests that the iroko ecosystem can act as a long-term carbon sink, as long as the calcium source is related to non-carbonate rocks. Consequently, this carbon sink, driven by the oxalate carbonate pathway around an iroko tree, constitutes a true carbon trapping ecosystem as defined by ecological theory.
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We compared the influence of the bug density in the capacity of Triatoma infestans and Panstrongylus megistus in obtaining blood meal in non anaesthetized mice. The regression anlysis for increase in body weight (mg) versus density (no. of bugs/mouse) showed that in experiments with anaesthetized mice (AM), no correlation was observed. In experiments with non anaesthetized mice (NAM) the weight increase was inversely proportional to density. The regression slope for blood meal size on density was less steep for T. infestans than for P. megistus (-1.9 and -3.0, respectively). The average weight increase of P. megistus nymphus in experiments with AM was higher than for T. infestans nymphs; however, in experiments with NAM such results were inverted. Mortality of P. megistus was significantly higher than of T. infestans with NAM. However, in experiments with AM very low mortality was observed. Considering the mortality and the slope of regression line on NAM, T. infestans is more efficient than P. megistus in obtaining blood meal in similar densities, possibly because it caused less irritation of the mice. The better exploitation of blood source of T. infestans when compared with P. megistus in similar densities, favours the maintenance of a better nutritional status in higher densities. This could explain epidemiological findings in which T. infestans not only succeeds in establishing larger colonies but also dislodges P. megistus in human dwellings when it is introduced in areas where the latter species prevails.
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Human RNA polymerase (Pol) III-transcribed genes are thought to share a simple termination signal constituted by four or more consecutive thymidine residues in the coding DNA strand, just downstream of the RNA 3'-end sequence. We found that a large set of human tRNA genes (tDNAs) do not display any T(≥4) stretch within 50 bp of 3'-flanking region. In vitro analysis of tDNAs with a distanced T(≥4) revealed the existence of non-canonical terminators resembling degenerate T(≥5) elements, which ensure significant termination but at the same time allow for the production of Pol III read-through pre-tRNAs with unusually long 3' trailers. A panel of such non-canonical signals was found to direct transcription termination of unusual Pol III-synthesized viral pre-miRNA transcripts in gammaherpesvirus 68-infected cells. Genome-wide location analysis revealed that human Pol III tends to trespass into the 3'-flanking regions of tDNAs, as expected from extensive terminator read-through. The widespread occurrence of partial termination suggests that the Pol III primary transcriptome in mammals is unexpectedly enriched in 3'-trailer sequences with the potential to contribute novel functional ncRNAs.
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Van der Woude syndrome (VWS), caused by dominant IRF6 mutation, is the most common cleft syndrome. In 15% of the patients, lip pits are absent and the phenotype mimics isolated clefts. Therefore, we hypothesized that some of the families classified as having non-syndromic inherited cleft lip and palate could have an IRF6 mutation. We screened in total 170 patients with cleft lip with or without cleft palate (CL/P): 75 were syndromic and 95 were a priori part of multiplex non-syndromic families. A mutation was identified in 62.7 and 3.3% of the patients, respectively. In one of the 95 a priori non-syndromic families with an autosomal dominant inheritance (family B), new insights into the family history revealed the presence, at birth, of lower lip pits in two members and the diagnosis was revised as VWS. A novel lower lip sign was observed in one individual in this family. Interestingly, a similar lower lip sign was also observed in one individual from a 2nd family (family A). This consists of 2 nodules below the lower lip on the external side. In a 3rd multiplex family (family C), a de novo mutation was identified in an a priori non-syndromic CL/P patient. Re-examination after mutation screening revealed the presence of a tiny pit-looking lesion on the inner side of the lower lip leading to a revised diagnosis of VWS. On the basis of this data, we conclude that IRF6 should be screened when any doubt rises about the normality of the lower lip and also if a non-syndromic cleft lip patient (with or without cleft palate) has a family history suggestive of autosomal dominant inheritance.
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Culex quinquefasciatus is known to be an efficient insect host of Wuchereria bancrofti. In Brazil Cx. quinquefasciatus is widely distributed throughout the country and is often abundant in and around human habitations. In contrast, Bancroftian filariasis is limited to three foci in Brazil. Experiments were undertaken to compare the vector capacities of Cx. quinquefasciatus originating from Maceió (Alagoas), one of the endemic areas of W. bancrofti infection in Brazil, and Belo Horizonte (Minas Gerais), a non endemic area. Laboratory-reared Cx. quinquefasciatus were dissected 20 days after blood feeding on microfilaraemic patients. Survival rates and the number of infective larvae that developed did not differ in female mosquitoes of different origins. Thus both populations of Culex were susceptible to infection with W. bancrofti
Gaussian estimates for the density of the non-linear stochastic heat equation in any space dimension
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In this paper, we establish lower and upper Gaussian bounds for the probability density of the mild solution to the stochastic heat equation with multiplicative noise and in any space dimension. The driving perturbation is a Gaussian noise which is white in time with some spatially homogeneous covariance. These estimates are obtained using tools of the Malliavin calculus. The most challenging part is the lower bound, which is obtained by adapting a general method developed by Kohatsu-Higa to the underlying spatially homogeneous Gaussian setting. Both lower and upper estimates have the same form: a Gaussian density with a variance which is equal to that of the mild solution of the corresponding linear equation with additive noise.
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BACKGROUND: Adherence to guidelines is associated with improved outcomes of patients with acute coronary syndrome (ACS). Clinical registries developed to assess quality of care at discharge often do not collect the reasons for non-prescription for proven efficacious preventive medication in Continental Europe. In a prospective cohort of patients hospitalized for an ACS, we aimed at measuring the rate of recommended treatment at discharge, using pre-specified quality indicators recommended in cardiologic guidelines and including systematic collection of reasons for non-prescription for preventive medications. METHODS: In a prospective cohort with 1260 patients hospitalized for ACS, we measured the rate of recommended treatment at discharge in 4 academic centers in Switzerland. Performance measures for medication at discharge were pre-specified according to guidelines, systematically collected for all patients and included in a centralized database. RESULTS: Six hundred and eighty eight patients(54.6%) were discharged with a main diagnosis of STEMI, 491(39%) of NSTEMI and 81(6.4%) of unstable angina. Mean age was 64 years and 21.3% were women. 94.6% were prescribed angiotensin converting enzyme inhibitors/angiotensin II receptor blockers at discharge when only considering raw prescription rates, but increased to 99.5% when including reasons non-prescription. For statins, rates increased from 98% to 98.6% when including reasons for non-prescription and for beta-blockers, from 82% to 93%. For aspirin, rates further increased from 99.4% to 100% and from to 99.8% to 100% for P2Y12 inhibitors. CONCLUSIONS: We found a very high adherence to ACS guidelines for drug prescriptions at discharge when including reasons for non-prescription to drug therapy. For beta-blockers, prescription rates were suboptimal, even after taking into account reason for non-prescription. In an era of improving quality of care to achieve 100% prescription rates at discharge unless contra-indicated, pre-specification of reasons for non-prescription for cardiovascular preventive medication permits to identify remaining gaps in quality of care at discharge. TRIAL REGISTRATION: ClinicalTrials.gov NCT01000701.
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Over the past decades, several sensitive post-electrophoretic stains have been developed for an identification of proteins in general, or for a specific detection of post-translational modifications such as phosphorylation, glycosylation or oxidation. Yet, for a visualization and quantification of protein differences, the differential two-dimensional gel electrophoresis, termed DIGE, has become the method of choice for a detection of differences in two sets of proteomes. The goal of this review is to evaluate the use of the most common non-covalent and covalent staining techniques in 2D electrophoresis gels, in order to obtain maximal information per electrophoresis gel and for an identification of potential biomarkers. We will also discuss the use of detergents during covalent labeling, the identification of oxidative modifications and review influence of detergents on finger prints analysis and MS/MS identification in relation to 2D electrophoresis.