987 resultados para 181-1122


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Taupo Volcanic Zone (TVZ), in the North Island, New Zealand, is arguably the most active Quaternary rhyolitic system in the world. Numerous and widespread rhyolitic tephra layers, sourced from the TVZ, form valuable chronostratigraphic markers in onshore and offshore sedimentary sequences. In deep-sea cores from Ocean Drilling Program (ODP) Leg 181 Sites 1125, 1124, 1123 and 1122, located east of New Zealand, ca 100 tephra beds are recognised post-dating the Plio-Pleistocene boundary at 1.81 Ma. These tephras have been dated by a combination of magnetostratigraphy, orbitally tuned stable-isotope data and isothermal plateau fission track ages. The widespread occurrence of ash offshore to the east of New Zealand is favoured by the small size of New Zealand, the explosivity of the mainly plinian and ignimbritic eruptions and the prevailing westerly wind field. Although some tephras can be directly attributed to known TVZ eruptions, there are many more tephras represented within ODP-cores that have yet to be recognised in near-source on-land sequences. This is due to proximal source area erosion and/or deep burial as well as the adverse effect of vapour phase alteration and devitrification within near-source welded ignimbrites. Despite these difficulties, a number of key deep-sea tephras can be reliably correlated to equivalent-aged tephra exposed in uplifted marine back-arc successions of Wanganui Basin where an excellent chronology has been developed based on magnetostratigraphy, orbitally calibrated sedimentary cycles and isothermal plateau fission track ages on tephra. Significant Pleistocene tephra markers include: the Kawakawa, Omataroa, Rangitawa/Onepuhi, Kaukatea, Kidnappers-B, Potaka, Unit D/Ahuroa, Ongatiti, Rewa, Sub-Rewa, Pakihikura, Ototoka and Table Flat Tephras. Six other tephra layers are correlated between ODP-core sites but have yet to be recognised within onshore records. The identification of Pleistocene TVZ-sourced tephras within the ODP record, and their correlation to Wanganui Basin and other onshore sites is a significant advance as it provides: (1) an even more detailed history of the TVZ than can be currently achieved from the near-source record, (2) a high-resolution tephrochronologic framework for future onshore-offshore paleoenvironmental reconstructions, and (3) well-dated tephra beds correlated from the offshore ODP sites with astronomically tuned timescales provide an opportunity to critically evaluate the chronostratigraphic framework for onshore Plio-Pleistocene sedimentary sequences (e.g. Wanganui Basin, cf. Naish et al. (1998, doi:10.1016/S0277-3791(97)00075-9).

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The 1122 (n=2) member of the Tl(Ca,Ba)n+1CunO2n+3 series containing a single Tl-O layer is shown to be associated with a Tc of 90 K. This value of Tc is significantly lower than that of the 2122 phase (Tcnot, vert, similar110 K) with two Tl-O layers.

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Substitution of Ca by Y in TlCaBa2Cu2Oy does not favour superconductivity, but substitution of Tl by Pb or of Ca by Ln (Ln = Y or rare earth) in TlCaSr2Cu2Oy results in high Tc superconductivity (Tc π 60-90 K). TlCa1-xLnxSr2Cu2Oy is a new series of high Tc superconductors, but the x = 0.0 composition does not exhibit bulk superconductivity.

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The 1122 member of the Tl(Ca, Sr)n+1CunO2n+3 system is stabilized by partial substitution of Tl by Pb. Tl1?xPbxCaSr2Cu2O7 with x=0.25 and 0.5 have both primitive tetragonal structures (c 12.1 Å) showing onset of superconductivity around 70 K and 90 K, respectively.

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Cow s milk allergy (CMA) affects about 2-6% of infants and young children. Environmental factors during early life are suggested to play a role in the development of allergic diseases. One of these factors is likely to be maternal diet during pregnancy and lactation. The association between maternal diet and development of CMA in offspring is not well known, but diet could contain factors that facilitate development of tolerance. After an established food allergy, another issue is gaining tolerance towards an antigen that causes symptoms. The strictness of the elimination depends on the individual level of tolerance. This study aimed at validating a questionnaire used to inquire about food allergies in children, at researching associations between maternal diet during pregnancy and lactation and subsequent development of cow s milk allergy in the offspring, and at evaluating the degree of adherence to a therapeutic elimination diet of children with CMA and factors associated with the adherence and age of recovery. These research questions were addressed in a prospective birth cohort born between 1997 and 2004 at the Tampere and Oulu University Hospitals. Altogether 6753 children of the Diabetes Prediction and Prevention (DIPP) Nutrition cohort were investigated. Questionnaires regarding allergic diseases are often used in studies without validation. High-quality valid tools are therefore needed. Two validation studies were conducted here: one by comparing parentally reported food allergies with information gathered from patient records of 1122 children, and the other one by comparing parentally reported CMA with information in the reimbursement records of special infant formulae in the registers of the Social Insurance Institution for 6753 children. Both of these studies showed that the questionnaire works well and is a valid tool for measuring food allergies in children. In the first validation study, Cohen s kappa values were within 0.71-0.88 for CMA, 0.74-0.82 for cereal allergy, and 0.66-0.86 for any reported food allergy. In the second validation study, the kappa value was 0.79, sensitivity 0.958, and specificity 0.965 for reported and diagnosed CMA. To investigate the associations between maternal diet during pregnancy and lactation and CMA in offspring, 6288 children were studied. Maternal diet during pregnancy (8th month) and lactation (3rd month) was assessed by a validated, 181-item semi-quantitative food frequency questionnaire (FFQ), and as an endpoint register-based information on diagnosed CMA was obtained from the Social Insurance Institution and complemented with parental reports of CMA in their children. The associations between maternal food consumption and CMA in offspring were analyzed by logistic regression comparing the highest and lowest quarters with two middle quarters of consumption and adjusted for several potential confounding factors. High maternal intake of milk products (OR 0.56, 95% CI 0.37-0.86 p = 0.002) was associated with a lower risk of CMA in offspring. When stratified according to maternal allergic rhinitis or asthma, a protective association of high use of milk products with CMA was seen in children of allergy-free mothers (OR 0.30, 95% CI 0.13 - 0.69, p < 0.001), but not in children of allergic mothers. Moreover, low maternal consumption of fish during pregnancy was associated with a higher risk of CMA in children of mothers with allergic rhinitis or asthma (OR 1.47, 95% CI 0.96 - 2.27 for the lowest quarter, p = 0.043). In children of nonallergic mothers, this association was not seen. Maternal diet during lactation was not associated with CMA in offspring, apart from an inverse association between citrus and kiwi fruit consumption and CMA. These results imply that maternal diet during pregnancy may contain factors protective against CMA in offspring, more so than maternal diet during lactation. These results need to be confirmed in other studies before giving recommendations to the public. To evaluate the degree of adherence to a therapeutic elimination diet in children with diagnosed CMA, food records of 267 children were studied. Subsequent food records were examined to assess the age at reintroduction of milk products to the child s diet. Nine of ten families adhered to the elimination diet of the child with extreme accuracy. Older and monosensitized children had more often small amounts of cow s milk protein in their diet (p < 0.001 for both). Adherence to the diet was not related to any other sociodemographic factor studied or to the age at reintroduction of milk products to the diet. Low intakes of vitamin D, calcium, and riboflavin are of concern in children following a cow s milk-free diet. In summary, we found that the questionnaires used in the DIPP study are valid in investigating CMA in young children; that there are associations between maternal diet during pregnancy and lactation and the development of CMA in offspring; and that the therapeutic elimination diet in children with diagnosed CMA is rigorously adhered to.

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(ES) En el presente artículo trata de poner de relieve los mecanismos utilizados por Aristófanes en Lisístrata para presentar de forma paródica el sacrificio juratorio con el que las mujeres sellan el pacto para obligar a sus maridos a que firmen la paz. Se analiza en este trabajo la utilización del vocabulario específico y la organización básica de este ritual, que Aristófanes conserva intacto, en contraste con la sustitución operada en cuanto a la persona que realiza el sacrificio y a la víctima sacrificial, una jarra de vino de Tasos. Esta elección entronca con el motivo cómico del amor de las mujeres al vino, al que se dedica la segunda parte de este trabajo.

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In recent times, some specialists have begun to study the subject of food selection of fish in an organized way, thus highlighting its importance. In the present work, the author intends to evaluate the impact of predation on the eupelagic zooplanktonic biocenosis of Lake Maggiore, producing, in this way, as far as possible, a basis for a better understanding of the population dynamics of the species of zooplankton directly involved. Another aspect which has been studied is that related to the mechanism of selective capture set in action by the predator. To this end the study tries to bear in mind that the subject should be interpreted as a function of numerous factors acting contemporaneously, that is as the interaction of characters peculiar to the predator and to the prey. The species studied, locally called ”bondella”, belongs to the family Salmonidae, subfamily Coregoninae and was introduced into Lake Maggiore in 1950.

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Contient : 1° « De Vita Christi » ; 2° « Le Traittié dit La Vengance de la mort Nostre Seigneur Jhesu Crist »

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La butirilcolinesterasa humana (BChE; EC 3.1.1.8) es una enzima polimórfica sintetizada en el hígado y en el tejido adiposo, ampliamente distribuida en el organismo y encargada de hidrolizar algunos ésteres de colina como la procaína, ésteres alifáticos como el ácido acetilsalicílico, fármacos como la metilprednisolona, el mivacurium y la succinilcolina y drogas de uso y/o abuso como la heroína y la cocaína. Es codificada por el gen BCHE (OMIM 177400), habiéndose identificado más de 100 variantes, algunas no estudiadas plenamente, además de la forma más frecuente, llamada usual o silvestre. Diferentes polimorfismos del gen BCHE se han relacionado con la síntesis de enzimas con niveles variados de actividad catalítica. Las bases moleculares de algunas de esas variantes genéticas han sido reportadas, entre las que se encuentra las variantes Atípica (A), fluoruro-resistente del tipo 1 y 2 (F-1 y F-2), silente (S), Kalow (K), James (J) y Hammersmith (H). En este estudio, en un grupo de pacientes se aplicó el instrumento validado Lifetime Severity Index for Cocaine Use Disorder (LSI-C) para evaluar la gravedad del consumo de “cocaína” a lo largo de la vida. Además, se determinaron Polimorfismos de Nucleótido Simple (SNPs) en el gen BCHE conocidos como responsables de reacciones adversas en pacientes consumidores de “cocaína” mediante secuenciación del gen y se predijo el efecto delos SNPs sobre la función y la estructura de la proteína, mediante el uso de herramientas bio-informáticas. El instrumento LSI-C ofreció resultados en cuatro dimensiones: consumo a lo largo de la vida, consumo reciente, dependencia psicológica e intento de abandono del consumo. Los estudios de análisis molecular permitieron observar dos SNPs codificantes (cSNPs) no sinónimos en el 27.3% de la muestra, c.293A>G (p.Asp98Gly) y c.1699G>A (p.Ala567Thr), localizados en los exones 2 y 4, que corresponden, desde el punto de vista funcional, a la variante Atípica (A) [dbSNP: rs1799807] y a la variante Kalow (K) [dbSNP: rs1803274] de la enzima BChE, respectivamente. Los estudios de predicción In silico establecieron para el SNP p.Asp98Gly un carácter patogénico, mientras que para el SNP p.Ala567Thr, mostraron un comportamiento neutro. El análisis de los resultados permite proponer la existencia de una relación entre polimorfismos o variantes genéticas responsables de una baja actividad catalítica y/o baja concentración plasmática de la enzima BChE y algunas de las reacciones adversas ocurridas en pacientes consumidores de cocaína.

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Incluye anexos de normativa legal, información sobre instituciones y sitios web