990 resultados para Latini, Brunetto, 1220-1295.


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Geological site characterisation programmes typically rely on drill cores for direct information on subsurface rocks. However, porosity, transport properties and porewater composition measured on drill cores can deviate from in-situ values due to two main artefacts caused by drilling and sample recovery: (1) mechanical disruption that increases porosity and (2) contamination of the porewater by drilling fluid. We investigated the effect and magnitude of these perturbations on large drill core samples (12–20 cm long, 5 cmdiameter) of high-grade, granitic gneisses obtained from 350 to 600 m depth in a borehole on Olkiluoto Island (SW Finland). The drilling fluid was traced with sodium–iodide. By combining out-diffusion experiments, gravimetry, UV-microscopy and iodide mass balance calculations, we successfully quantified the magnitudes of the artefacts: 2–6% increase in porosity relative to the bulk connected porosity and 0.9 to 8.9 vol.% contamination by drilling fluid. The spatial distribution of the drilling-induced perturbations was revealed by numerical simulations of 2D diffusion matched to the experimental data. This showed that the rims of the samples have a mechanically disrupted zone 0.04 to 0.22 cm wide, characterised by faster transport properties compared to the undisturbed centre (1.8 to 7.7 times higher pore diffusion coefficient). Chemical contamination was shown to affect an even wider zone in all samples, ranging from 0.15 to 0.60 cm, inwhich iodide enrichmentwas up to 180 mg/kgwater, compared to 0.5 mg/kgwater in the uncontaminated centre. For all samples in the present case study, it turned out that the magnitude of the artefacts caused by drilling and sample recovery is so small that no correction is required for their effects. Therefore, the standard laboratory measurements of porosity, transport properties and porewater composition can be taken as valid in-situ estimates. However, it is clear that the magnitudes strongly depend on site- and drilling-specific factors and therefore our results cannot be transferred simply to other locations. We recommend the approach presented in this study as a route to obtain reliable values in future drilling campaigns aimed at characterising in-situ bedrock properties.

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BACKGROUND Everolimus (ERL) has become an alternative to calcineurin inhibitors (CNIs) due to its renal-sparing properties, especially in heart transplant (HTx) recipients with kidney dysfunction. However, ERL dosing is challenging due to its narrow therapeutic window combined with high inter-individual pharmacokinetic variability. Our aim was to evaluate the effect of clinical and genetic factors on ERL dosing in a pilot cohort of 37 HTx recipients. METHODS Variants in CYP3A5, CYP3A4, CYP2C8, POR, NR1I2, and ABCB1 were genotyped and clinical data were retrieved from patient charts. RESULTS While ERL trough concentration (C0 ) was within the targeted range for most patients, over 30-fold variability in the dose-adjusted ERL C0 was observed. Regression analysis revealed a significant effect of the non-functional CYP3A5*3 variant on the dose-adjusted ERL C0 (P = 0.031). ERL dose requirement was 0.02 mg/kg/day higher in patients with CYP3A5*1/*3 genotype compared to patients with CYP3A5*3/*3 to reach the targeted C0 (P = 0.041). ERL therapy substantially improved estimated glomerular filtration rate (28.6 ± 6.6 ml/min/1.73m(2) ) in patients with baseline kidney dysfunction. CONCLUSION ERL pharmacokinetics in HTx recipients is highly variable. Our preliminary data on patients on a CNI-free therapy regimen suggest that CYP3A5 genetic variation may contribute to this variability. This article is protected by copyright. All rights reserved.

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OBJECTIVE: This research was aimed to determine the occurrence of Brachyspira (B.) hyodysenteriae in Swiss multiplier pig herds. MATERIALS AND METHODS: In a pilot study a direct real-time polymerase chain reaction (PCR) method for B. hyodysenteriae was compared to culture followed by PCR on 106 samples from three herds. Subsequently 40 multiplier herds were epidemiologically characterized and analysed for the presence of B. hyodysenteriae using direct PCR on 1412 rectal swabs. For external validation 20 swabs obtained from two positive conventional herds were analysed. RESULTS: The comparison of direct PCR with culture followed by PCR resulted in a moderate agreement (kappa index: 0.58). In the two conventional herds, 35% of the samples (7/20) tested positive. Samples from 39 multipliers tested negative. In one multiplier herd, 25% (9/36) of the samples tested PCR positive. Risk factors in the multiplier herd may have been rodents or birds, but not pig purchase. CONCLUSION AND CLINICAL RELEVANCE: B. hyodysenteriae have been detected in a Swiss multiplier herd, which underlines the threat of potential spread by replacement pigs. Consequently, a Brachyspira monitoring programme was established for Swiss multiplier herds.

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PURPOSE In the past few years more and more research focused on psychosocial risk factors of cardiovascular disease, including depression. This review focuses on depression as a long-term risk factor for acute coronary syndrome in initially heart disease-free people. METHODS The studies included (n = 15) comprised people without heart disease who were exposed to depression. The outcome was acute coronary syndrome (acute myocardial infarction, instable angina pectoris, sudden cardiac death). Only articles published in English between 2000 and 2013 were considered. RESULTS Most but not all studies found an association between depression and cardiac outcome. Possible explanations for the inconsistency of the findings are discussed. CONCLUSIONS Most likely there is an association between depression and acute coronary syndrome. However, it remains unclear whether depression acts as an independent risk factor for developing an acute coronary syndrome, or if depression promotes the development of an acute coronary syndrome by indirect means.

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Ray (1998) developed measures of input- and output-oriented scale efficiency that can be directly computed from an estimated Translog frontier production function. This note extends the earlier results from Ray (1998) to the multiple-output multiple input case.

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The Ottoman government obtained current information on the empire's sources of revenue through periodic registers called tahrir defterleri. These documents include detailed information on tax-paying subjects and taxable resources, making it possible to study the economic and social history of the Middle East and Eastern Europe in the fifteenth and sixteenth centuries. Although the use of these documents have been typically limited to the construction of local histories, adopting a more optimistic attitude toward their potential and using appropriate sampling procedures can greatly increase their contribution to historical scholarship. They can be used in comprehensive quantitative studies and in addressing questions of broader historical significance or larger social scientific relevance.

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The female reproductive tract (FRT) develops midway through embryogenesis, and consists of oviducts, uterine horns, cervix and upper part of the vagina. The uterine horns are composed of an epithelial layer, luminal (LE) and glandular epithelium (GE), surrounded by a mesenchymal layer, the stroma and myometrium. Interestingly, in most mammals the GE forms after birth and it only becomes fully differentiated as the female reaches sexual maturity. Uterine glands (UG) are made up of GE and are present in all mammals. They secrete nutrients, cytokines and several other proteins, termed histotroph, that are necessary for embryo implantation and development. Experiments in ewes and mice have revealed that females who lack UGs are infertile mainly due to impaired implantation and early pregnancy loss, suggesting that UGs are essential for fertility. Fortunately for us, UGs develop after birth allowing us to peer into the genetic mechanism of tubulogenesis and branching morphogenesis; two processes that are disrupted in various adenocarcinomas (cancer derived from glands). We created 3D replicas of the epithelium lining the FRT using optical projection tomography and characterized UG development in mice using lineagetracing experiments. Our findings indicate that mouse UGs develop as simple tubular structures and later grow multiple secretory units that stem from the main duct. The main aim of this project was to study the role of SOX9 in the UGs. Preliminary studies revealed that Sox9 is mostly found in the nucleus of the GE. vii This observation led to the hypothesis that Sox9 plays a role in the formation and/or differentiation of the GE. To study the role of Sox9 in UGs differentiation, we conditionally knocked out and overexpressed Sox9 in both the LE and GE using the progesterone receptor (Pgr) promoter. Overexpressing Sox9 in the uterine epithelium, parts of the stroma, and myometrium led to formation of multiple cystic structures inside the endometrium. Histological analysis revealed that these structures appeared morphologically similar to structures present in histological tissue sections obtained from patients with endometrial polyps. We have accounted for the presence of simple and complex hyperplasia with atypia, metaplasia, thick-walled blood vessels, and stromal fibrosis; all “hallmarks” that indicate overexpressing Sox9 leads to development of a polyp-like morphology. Therefore, we can propose the use of Sox9-cOE mice to study development of endometrial cystic lesions and disease progression into hyperplastic lesions.

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A 181 m deep ice core drilled in 1994/95 on the south dome of Berkner Island, Antarctica, was analyzed for stable isotopes, major ions and microparticle concentrations. Samples for ion chromatography were prepared by using a novel technique of filling decontaminated sample from a device for continuous ice-core melting directly into the sample vials. The core was dated through identification of volcanic horizons and interpolative layer counting. The core, together with a similar core from the north dome, reveals a 1000 year history of relatively stable climate. Temporal variations in the two cores deviate from each other owing to changing patterns of regional-scale circulation; the best correspondence between them is found for MSA-. delta18O, accumulation rate and a sea-salt proxy show only negligible correlation, which suggests a complex meteorological setting. Increasing annual accumulation is observed for the last 100 years. A period of increased sea-salt concentrations started around AD 1405, as has also been observed in other cores. Microparticle concentrations are on average 1220 particles (>=1.0 ?m diameter)/mL; they are enhanced from AD 1200 to 1350, possibly because of a higher atmospheric mineral dust load or because local volcanic activity was stronger than previously thought. Microparticles and NH4+show marked but multiple and very irregular sub-annual peaks; long-term stacking of 1 year data intervals yields seasonal maxima in austral spring or mid-summer, respectively. Post-depositional redistribution was observed for MSA, NO3- and F- at volcanic horizons.

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El trabajo recorre críticamente cuatro textos del musicólogo finés Eero Tarasti. Los mismos apuntan a la refundación de una nueva semiótica, la semiótica existencial que, si bien se basa en los postulados tradicionales de esa disciplina, provee una mirada más fenomenológica y antropomorfa. Se sintetizan también los aportes fundamentales de Tarasti, especialmente en relación a su aplicación en la investigación musical. Estos aportes son ejes tácitos que recorren solapadamente su obra, pero que apuntan en todos los casos a la superación de la semiótica “esclerotizada".

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En el presente trabajo se muestran los resultados de las investigaciones realizadas en el Instituto de Investigaciones Fundamentales en Agricultura Tropical (INIFAT), acerca de la acción del almacenamiento sobre la semilla de Nim y sus componentes. Se pudo determinar que durante el proceso de beneficio de los frutos de Nim cosechados sólo una cuarta parte del volumen de los frutos se convierte en semillas, definiéndose además que el peso de un fruto maduro es de 1.8 g y de una semilla seca 0.4 g. Por otra parte, se pudo conocer que en el proceso de almacenamiento de la semilla seca de Nim se produce una disminución notable del peso de la misma y sus componentes (almendra, aceite, torta y residuo), dada por la influencia del tiempo de almacenamiento y factores ambientales tales como humedad relativa y temperatura. Además, se observó de igual forma, que la mayor pérdida de peso de la semilla se produjo durante los dos primeros meses de almacenadas, que incluyen el período de envejecimiento fisiológico.