965 resultados para Pseudo-pelger-huet Anomaly
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Compte tenu des relations étroites existant entre le pouvoir politique et l'histoire - et plus particulièrement l'enseignement de l'histoire à l'école - , les manuels constituent un objet d'étude privilégié de l'évolution des relations pouvoir/enseignement. Ils fournissent un lieu de médiation privilégié entre les savoirs savants et les savoirs scolaires institutionnels ; ils permettent d'observer les conceptions didactiques préconisées par l'institution scolaire. Si, sous l'égide de l'Etat-nation au 19e siècle, les savoirs savants historiques et les savoirs scolaires étaient entremêlés, les rapports se sont complexifiés durant le 20e siècle en raison notamment de la prise de distance progressive de l'histoire savante à l'égard du pouvoir. Petit à petit, à partir des années 1930, le concept d'histoire- problème, initié par l'école historique des Annales, dépasse l'histoire-récit de l'école historique positiviste (méthodique) du 19e siècle et sa traduction du récit- national au coeur de la leçon d'histoire. Cependant, si après 1945, l'école des Annales, puis la Nouvelle histoire, tendent à s'imposer dans le champ de l'histoire savante francophone, elles se heurtent à une tradition scolaire bien établie et modifient peu et tardivement les curricula, les manuels et les pratiques enseignantes. Progressivement donc, une fracture apparaît entre l'histoire savante et l'histoire scolaire. Dans cette étude, notre travail envisage l'analyse du manuel d'histoire en tant qu'objet hybride. Il est à la fois porteur d'un texte historien, ouvrage de vulgarisation et de référence, ainsi qu'outil pédagogico-didactique. Par ailleurs, le manuel d'histoire a la charge de transmettre des valeurs, car les finalités attribuées par l'autorité politique, via les autorités scolaires, à l'histoire scolaire comportent toujours une dimension forte de formation du futur citoyen. Au texte de départ sont associés des documents textuels ou iconiques, des résumés, des questions regroupées par chapitre, un glossaire ou une chronologie générale. De plus, ce texte est encadré d'un dispositif didactique plus ou moins explicite : préface, numérotation par paragraphe correspondant à la leçon du jour, dates mises en évidence, aide-mémoire et questions. Par ailleurs, les découpages en livres ou en parties peuvent correspondre à des années (ou parties d'années) de programme. Il sera donc également étudié pour les spécificités d'un sous-genre de discours à définir : les manuels - d'histoire - produits (et utilisés) dans le canton de Vaud au 20e siècle. En conséquence, notre travail se propose d'observer et d'analyser les manuels d'histoire vaudois sous deux modalités préférentielles. Premièrement, celle des formes constitutives et évolutives prises par le manuel pour se construire comme un discours légitimé (deuxième partie : écriture et mise en scène de l'histoire). Deuxièmement, celle de la mise en scène d'une histoire à visée pseudo- pédagogique masquant l'intégration du discours de l'autorité politique (troisième partie : comment l'autorité vient au discours). Site internet : http://manuelshistoire.ch
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Neutron-scattering techniques have been used to study the premartensitic state of a family of Cu-Al-Be alloys, which transform from the bcc phase to an 18R martensitic structure. We find that the phonon modes of the TA2[110] branch have very low energies with anomalous temperature dependence. A slight anomaly at q=2/3 was observed; this anomaly, however, does not change significantly with temperature. No elastic peaks, related to the martensite structure, were found in the premartensitic state of these alloys. The results are compared with measurements, performed under the same instrumental conditions, on two Cu-Al-Ni and a Cu-Zn-Al martensitic alloy.
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1. Identifying the boundary of a species' niche from observational and environmental data is a common problem in ecology and conservation biology and a variety of techniques have been developed or applied to model niches and predict distributions. Here, we examine the performance of some pattern-recognition methods as ecological niche models (ENMs). Particularly, one-class pattern recognition is a flexible and seldom used methodology for modelling ecological niches and distributions from presence-only data. The development of one-class methods that perform comparably to two-class methods (for presence/absence data) would remove modelling decisions about sampling pseudo-absences or background data points when absence points are unavailable. 2. We studied nine methods for one-class classification and seven methods for two-class classification (five common to both), all primarily used in pattern recognition and therefore not common in species distribution and ecological niche modelling, across a set of 106 mountain plant species for which presence-absence data was available. We assessed accuracy using standard metrics and compared trade-offs in omission and commission errors between classification groups as well as effects of prevalence and spatial autocorrelation on accuracy. 3. One-class models fit to presence-only data were comparable to two-class models fit to presence-absence data when performance was evaluated with a measure weighting omission and commission errors equally. One-class models were superior for reducing omission errors (i.e. yielding higher sensitivity), and two-classes models were superior for reducing commission errors (i.e. yielding higher specificity). For these methods, spatial autocorrelation was only influential when prevalence was low. 4. These results differ from previous efforts to evaluate alternative modelling approaches to build ENM and are particularly noteworthy because data are from exhaustively sampled populations minimizing false absence records. Accurate, transferable models of species' ecological niches and distributions are needed to advance ecological research and are crucial for effective environmental planning and conservation; the pattern-recognition approaches studied here show good potential for future modelling studies. This study also provides an introduction to promising methods for ecological modelling inherited from the pattern-recognition discipline.
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The TA2 phonon dispersion curves of Ni-Mn-Ga alloys with different compositions which transform to different martensitic structures have been measured over a broad temperature range covering both paramagnetic and ferromagnetic phases. The branches show an anomaly (dip) at a wave number that depends on the particular martensitic structure, and there is softening of these anomalous phonons with decreasing temperature. This softening is enhanced below the Curie point, as a consequence of spin-phonon coupling. This effect is stronger for systems with higher electronic concentration.
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With the aging population and its rapidly increasing prevalence, dementia has become an important public health concern in developed and developing countries. To date, the pharmacological treatment is symptomatic and based on the observed neurotransmitter disturbances. The four most commonly used drugs are donepezil, galantamine, rivastigmine and memantine. Donepezil, galantamine and rivastigmine are acetylcholinesterase inhibitors with different pharmacodynamic and pharmacokinetic profiles. Donepezil inhibits selectively the acetylcholinesterase and has a long elimination half-life (t½) of 70 h. Galantamine is also a selective acetylcholinesterase inhibitor, but also modulates presynaptic nicotinic receptors. It has a t½ of 6-8 h. Donepezil and galantamine are mainly metabolised by cytochrome P450 (CYP) 2D6 and CYP3A4 in the liver. Rivastigmine is a so-called 'pseudo-irreversible' inhibitor of acetylcholinesterase and butyrylcholinesterase. The t½ of the drug is very short (1-2 h), but the duration of action is longer as the enzymes are blocked for around 8.5 and 3.5 h, respectively. Rivastigmine is metabolised by esterases in liver and intestine. Memantine is a non-competitive low-affinity antagonist of the NMDA receptor with a t½ of 70 h. Its major route of elimination is unchanged via the kidneys. Addressing the issue of inter-patient variability in treatment response might be of special importance for the vulnerable population taking anti-dementia drugs. Pharmacogenetic considerations might help to avoid multiple medication changes due to non-response and/or adverse events. Some pharmacogenetic studies conducted on donepezil and galantamine reported an influence of the CYP2D6 genotype on the pharmacokinetics of the drugs and/or on the response to treatment. Moreover, polymorphisms in genes of the cholinergic markers acetylcholinesterase, butyrylcholinesterase, choline acetyltransferase and paraoxonase were found to be associated with better clinical response to acetylcholinesterase inhibitors. However, confirmation studies in larger populations are necessary to establish evidence of which subgroups of patients will most likely benefit from anti-dementia drugs. The aim of this review is to summarize the pharmacodynamics and pharmacokinetics of the four commonly used anti-dementia drugs and to give an overview on the current knowledge of pharmacogenetics in this field.
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Alteplase has been shown to be effective in preventing central venous access clotting in patients on hemodialysis. Because of a high phosphorus content in its excipient, it can inadvertently contaminate blood samples, leading the physician in care of the patient to erroneously increase dialysis time or change diet in order to control the pseudo-hyperphosphatemia.
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An eclogite facies meta-plagiogranite from the Lanzo massif (western Alps, Italy) contains crystals of zircon intimately associated with allanite. Zircon displays different microtextures ranging from pristine, euhedral, and magmatic to fractured, porous varieties with mosaic zoning, and pervasive recrystallization into euhedral microcrystals. Fractures and voids in the recrystallized zircon microcrystals are mainly filled by high-pressure Na-rich pyroxene. Electron backscattered diffraction analysis revealed a similar crystallographic orientation for primary magmatic zircon crystals and microcrystals, with less than 2 degrees misorientation among neighboring microdomains. The textural change is coupled with chemical and isotopic modifications: recrystallized zircon domains contain significantly less Th and light- to mid-REE, but are richer in Sr than magmatic zircon crystals. Magmatic zircon preserves the protolith U-Pb age of 163.5 +/- 1.7 Ma, whereas zircon microcrystals have a mean age of 55 +/- 1 Ma. The coexisting allanite also contains inclusions of Na-rich pyroxene and has chemical features (elevated Sr and Ni contents and lack of Eu anomaly) indicating formation at high pressure. Despite being associated texturally with zircon, allanite yields a younger Th-Pb age of 46.5 +/- 3.0 Ma, suggesting that the Lanzo unit remained at relatively high pressure conditions for similar to 8 m.y. Zircon recrystallization proceeded with volume reduction and loss of material to an alkaline metamorphic fluid that acted as the agent for a coupled dissolution-reprecipitation process. Recrystallization occurred with minimum transport, in a low-strain environment, and was not significantly enhanced by metamictization. The source of the fluid for zircon recrystallization is most probably related to prograde devolatilization reactions in the surrounding serpentinite.
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Eucalyptus Shoot Blight in the Vale do Rio Doce (ESBVRD) is an anomaly that leads to reduced growth and, in more extreme cases, to death of eucalyptus plants. Initially diagnosed in plantations in the region of the Vale do Rio Doce, in the State of Minas Gerais, Brazil, this problem has also been found in plantations in other regions of the country and even in other countries. Although the symptoms of this anomaly are well-known, its causes are not yet understood. The aim of this study was to evaluate the cause-effect relationship between accumulation of manganese (Mn) in eucalyptus clones and ESBVRD. Characterization of the environment in areas of greater occurrence of this problem in regard to soil, climate and fluctuation of the water table was undertaken in eucalyptus plantations of the Celulose Nipo-brasileira S.A. (Cenibra) company in the region of the Vale do Rio Doce. Plant tissues were sampled in two situations. In the first situation, diagnosis occurred in the initial phase of the anomaly in clones with differentiated tolerance to the problem; in the second situation, diagnosis was made in a single clone, considered to be sensitive, in two time periods - in the phase with the strong presence of symptoms and in the recovery phase, in areas of occurrence and in areas of escape from the problem. The most ESBVRD-sensitive clone showed much higher (4.8 times higher) leaf Mn contents than more tolerant clones. In plants with the anomaly, Mn leaf contents were greater than 3,070 mg kg-1, much greater than the quantity found in those without the anomaly (734 mg kg-1). In the period in which the symptoms began to wane, there was a sharp decline in leaf Mn contents, from 2,194 to 847 mg kg-1. Manganese content in the above ground part and plant litter (44.4 g ha-1) in the area of occurrence of the anomaly was three times greater than that found in these same components (14.1 g ha-1) in the area of absence of the symptom. Based on the evidence found, such as the existence of environmental conditions favorable to high Mn availability to the plants in the areas of greatest incidence of ESBVRD, greater uptake of Mn in sensitive clones and in plants with symptoms, and a synchronism between the intensity of symptoms of ESBVRD and leaf Mn contents, it may be inferred that temporary excess of Mn in eucalyptus plants is closely related to ESBVRD.
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In this study, we present a detailed structural characterization by means of transmission electron microscopy and Raman spectroscopy of polymorphous silicon (pm-Si:H) thin films deposited using radio-frequency dust-forming plasmas of SiH4 diluted in Ar. Square-wave modulation of the plasma and gas temperature was varied to obtain films with different nanostructures. Transmission electron microscopy and electron diffraction have shown the presence of Si crystallites of around 2 nm in the pm-Si:H films, which are related to the nanoparticles formed in the plasma gas phase coming from their different growth stages, named particle nucleation and coagulation. Raman scattering has proved the role of the film nanostructure in the crystallization process induced ¿in situ¿ by laser heating.
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PURPOSE: We preoperatively assessed neurovesical function and spinal cord function in children with anorectal malformations. In cases of neurovesical dysfunction we looked for an association with vertebral malformation or myelodysplasia. MATERIALS AND METHODS: We prospectively evaluated 80 children with anorectal malformations via preoperative urodynamics and magnetic resonance imaging of the spine. Bladder compliance and volume, detrusor activity and vesicosphincteric synergy during voiding allowed urodynamic evaluation. Results were reported according to Wingspread and Krickenbeck classifications of anorectal malformations. RESULTS: Urodynamic findings were pathological in 14 children (18%). Pathological evaluations did not seem related to type of fistula or level of anorectal malformation. Vertebral anomalies were seen in 34 patients (43%) and myelodysplasia in 16 (20%). Neither vertebral anomaly nor myelodysplasia seemed associated with type of fistula or severity of anorectal malformation. Of 14 children with pathological urodynamics no vertebral anomaly or myelodysplasia was found in 7. Of 66 children with normal urodynamics 40 presented with vertebral or spinal malformation. CONCLUSIONS: Lower urinary tract dysfunction is common in patients with anorectal malformations. Normal spine or spinal cord does not exclude neurovesical dysfunction. Myelodysplasia or vertebral anomaly does not determine lower urinary tract dysfunction. Thus, we recommend preoperative urodynamic assessment of the bladder and magnetic resonance imaging of the spine in children with anorectal malformations.
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Dieser Beitrag geht davon aus, dass eine neue Gattung in anderen europäischen Sprachen und Kulturen bereits vorhandene Gattungsformen ,"(re)konfiguriert", um sie der eigenen Sprache und Kultur anzupassen und neue Aussageformen zu schaffen. Dieser Prozess wird am Beispiel der europäischen Märchen aufgezeigt, die der hier formulierten Hypothese nach weder Erzeugnisse einer Universalgattung noch nationaler Folklore sind, sondern komplexe ,"Rekonfigurationen" lateinischer, italienischen und französischer Gattungsformen. Am Beispiel der Histoires ou contes du temps passé, avec des Moralités von 1697 wird gezeigt, wie Charles Perrault mit einer neuartigen ,"Szenographie" das zum Gattungsparadigma gewordene Psyche-Märchen von Apuleius ,"rekonfiguiert". An die Stelle des erzählenden Esels Lucius, der vorgibt, Psyches Geschichte von der alten Magd einer Räuberbande gehört zu haben, setzt Perrault seinen Sohn, Pierre Darmancour, und schafft mit einer pseudo-naiven Szenographie eine neue Gattung, die von den Brüdern Grimm und deren ,"Beiträgerinnen" hugenottischer Herkunft zum Kinder- und Hausmärchen umgearbeitet wird.
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BACKGROUND: Holt-Oram syndrome (HOS) is an autosomal dominant disorder characterised by upper limb anomalies and congenital heart defects. We present epidemiological and clinical aspects of HOS patients using data from EUROCAT (European Surveillance of Congenital Anomalies) registries. METHODS: The study was based on data collected during 1990-2011 by 34 registries. The registries are population-based and use multiple sources of information to collect data on all types of birth using standardized definitions, methodology and coding. Diagnostic criteria for inclusion in the study were the presence of radial ray abnormalities and congenital heart disease (CHD), or the presence of either radial ray anomaly or CHD, with family history of HOS. RESULTS: A total of 73 cases of HOS were identified, including 11 (15.1%) TOPFA and 62 (84.9%) LB. Out of 73 HOS cases, 30.8% (20/65) were suspected prenatally, 55.4% (36/65) at birth, 10.7% (7/65) in the first week of life, and 3.1% (2/65) in the first year of life. The prenatal detection rate was 39.2% (20/51), with no significant change over the study period. In 55% (11/20) of prenatally detected cases, parents decided to terminate pregnancy. Thumb anomalies were reported in all cases. Agenesis/hypoplasia of radius was present in 49.2% (30/61), ulnar aplasia/hypoplasia in 24.6% (15/61) and humerus hypoplasia/phocomelia in 42.6% (26/61) of patients. Congenital heart defects (CHD) were recorded in 78.7% (48/61) of patients. Isolated septal defects were present in 54.2 (26/48), while 25% (12/48) of patients had complex/severe CHD. The mean prevalence of HOS diagnosed prenatally or in the early years of life in European registries was 0.7 per 100,000 births or 1:135,615 births. CONCLUSIONS: HOS is a rare genetic condition showing regional variation in its prevalence. It is often missed prenatally, in spite of the existence of major structural anomalies. When discovered, parents in 45% (9/20) of cases opt for the continuation of pregnancy. Although a quarter of patients have severe CHD, the overall first week survival is very good, which is important information for counselling purposes.
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In inflationary cosmological models driven by an inflaton field the origin of the primordial inhomogeneities which are responsible for large-scale structure formation are the quantum fluctuations of the inflaton field. These are usually calculated using the standard theory of cosmological perturbations, where both the gravitational and the inflaton fields are linearly perturbed and quantized. The correlation functions for the primordial metric fluctuations and their power spectrum are then computed. Here we introduce an alternative procedure for calculating the metric correlations based on the Einstein-Langevin equation which emerges in the framework of stochastic semiclassical gravity. We show that the correlation functions for the metric perturbations that follow from the Einstein-Langevin formalism coincide with those obtained with the usual quantization procedures when the scalar field perturbations are linearized. This method is explicitly applied to a simple model of chaotic inflation consisting of a Robertson-Walker background, which undergoes a quasi-de Sitter expansion, minimally coupled to a free massive quantum scalar field. The technique based on the Einstein-Langevin equation can, however, deal naturally with the perturbations of the scalar field even beyond the linear approximation, as is actually required in inflationary models which are not driven by an inflaton field, such as Starobinsky¿s trace-anomaly driven inflation or when calculating corrections due to nonlinear quantum effects in the usual inflaton driven models.
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Quartz-carbonate-chlorite veins were studied in borehole samples of the RWTH-1 well in Aachen. Veins formed in Devonian rocks in the footwall of the Aachen thrust during Variscan deformation and associated fluid flow. Primary fluid inclusions indicate subsolvus unmixing of a homogenous H(2)O-CO(2)-CH(4)-(N(2))-Na-(K)-Cl fluid into a H(2)O-Na-(K)-Cl solution and a vapour-rich CO(2)-(H(2)O, CH(4), N(2)) fluid. The aqueous end-member composition resembles that of metamorphic fluids of the Variscan front zone with salinities ranging from 4 to 7% NaCl equiv. and maximum homogenisation temperatures of close to 400A degrees C. Pressure estimates indicate a burial depth between 4,500 and 8,000 m at geothermal gradients between 50 and 75A degrees C/26 MPa, but pressure decrease to sublithostatic conditions is also indicated, probably as a consequence of fracture opening during episodic seismic activity. A second fluid system, mainly preserved in pseudo-secondary and secondary fluid inclusions, is characterised by fluid temperatures between 200 and 250A degrees C and salinities of < 5% NaCl equiv. Bulk stable isotope analyses of fluids released from vein quartz, calcite, and dolomite by decrepitation yielded delta D(H2O) values from -89 to -113 aEuro degrees, delta(13)C(CH4) from -26.9 to -28.9aEuro degrees (VPDB) and delta(13)C(CO2) from -12.8 to -23.3aEuro degrees (VPDB). The low delta D and delta(13)C range of the fluids is considered to be due to interaction with cracked hydrocarbons. The second fluid influx caused partial isotope exchange and disequilibrium. It is envisaged that an initial short lived flux of hot metamorphic fluids expelled from the epizonal metamorphic domains of the Stavelot-Venn massif. The metamorphic fluid was focused along major thrust faults of the Variscan front zone such as the Aachen thrust. A second fluid influx was introduced from formation waters in the footwall of the Aachen thrust as a consequence of progressive deformation. Mixing of the cooler and lower salinity formation water with the hot metamorphic fluid during episodic fluid trapping resulted in an evolving range of physicochemical fluid inclusion characteristics.
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OBJECTIVES: To determine the risk of a Down syndrome (DS) live birth for women 45 years of age and over. METHODS: A meta-analysis of data from five published articles, 13 EUROCAT congenital anomaly population registers and two unpublished sources. RESULTS: Information was available on the number of DS live births occurring amongst 13,745 live births to women 45 years of age and over. Information was also available on DS pregnancies diagnosed prenatally that were subsequently terminated. These pregnancies were adjusted for expected fetal loss to estimate the number of live births that would have occurred in the absence of prenatal diagnoses, when a total of 471 DS live births were estimated to have occurred. The risk of a DS birth did not increase for women 45 years of age and over. The average risk was 34 per 1000 births (95% CI: 31-37). CONCLUSION: The risk of a DS live birth for women 45 years of age and over is considerably lower than has often been previously assumed. The most likely explanation is that women of this age are more likely to miscarry DS pregnancies than younger mothers.