6 research outputs found

    Evaluating the importance of metamorphism in the foundering of continental crust

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    The metamorphic conditions and mechanisms required to induce foundering in deep arc crust are assessed using an example of representative lower crust in SW New Zealand. Composite plutons of Cretaceous monzodiorite and gabbro were emplaced at ~1.2 and 1.8 GPa are parts of the Western Fiordland Orthogneiss (WFO); examples of the plutons are tectonically juxtaposed along a structure that excised ~25 km of crust. The 1.8 GPa Breaksea Orthogneiss includes suitably dense minor components (e.g. eclogite) capable of foundering at peak conditions. As the eclogite facies boundary has a positive dP/dT, cooling from supra-solidus conditions (T > 950 ºC) at high-P should be accompanied by omphacite and garnet growth. However, a high monzodioritic proportion and inefficient metamorphism in the Breaksea Orthogneiss resulted in its positive buoyancy and preservation. Metamorphic inefficiency and compositional relationships in the 1.2 GPa Malaspina Pluton meant it was never likely to have developed densities sufficiently high to founder. These relationships suggest that the deep arc crust must have primarily involved significant igneous accumulation of garnet–clinopyroxene (in proportions >75%). Crustal dismemberment with or without the development of extensional shear zones is proposed to have induced foundering of excised cumulate material at P > 1.2 GPa

    Contemporary management of primary parapharyngeal space tumors

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    The parapharyngeal space is a complex anatomical area. Primary parapharyngeal tumors are rare tumors and 80% of them are benign. A variety of tumor types can develop in this location; most common are salivary gland neoplasm and neurogenic tumors. The management of these tumors has improved greatly owing to the developments in imaging techniques, surgery, and radiotherapy. Most tumors can be removed with a low rate of complications and recurrence. The transcervical approach is the most frequently used. In some cases, minimally invasive approaches may be used alone or in combination with a limited transcervical route, allowing large tumors to be removed by reducing morbidity of expanded approaches. An adequate knowledge of the anatomy and a careful surgical plan is essential to tailor management according to the patient and the tumor. The purpose of the present review was to update current aspects of knowledge related to this more challenging area of tumor occurrence.Peer reviewe

    Short-term health-related quality of life and symptom control with docetaxel, cisplatin, 5-fluorouracil and cisplatin (TPF), 5-fluorouracil (PF) for induction in unresectable locoregionally advanced head and neck cancer patients (EORTC 24971/TAX 323)

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    BACKGROUND: The EORTC 24971/TAX 323, a phase III study of 358 patients with unresectable locoregionally advanced squamous cell carcinoma of the head and neck, showed an improved progression-free and overall survival (OS) with less toxicity when docetaxel (T) was added to cisplatin and 5-fluorouracil (PF) for induction and given before radiotherapy (RT). The impact of the addition of docetaxel on patients' health-related quality of life (HRQOL) and symptoms was investigated. METHODS: HRQOL was assessed at baseline, at end of cycle 2, and 4, 6, and 9 months after completion of RT using the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire C30 (QLQ-C30) and the EORTC QLQ Head and Neck Cancer-Specific Module (EORTC QLQ-H&N35). The primary HRQOL scale was global HRQOL per protocol. RESULTS: Compliance to HRQOL assessments was 97% at baseline, but dropped to 54% by 6 months. Data were analysed up to 6 months. There was a trend towards improved global HRQOL during the treatment period. At 6 months after the end of RT, global HRQOL was higher in the TPF arm than in the PF arm, but the low compliance does not allow to draw definitive conclusions. Swallowing and coughing problems decreased more in the TPF arm than in the PF arm at the end of cycle 2, but to a limited extent. CONCLUSION: Induction chemotherapy with TPF before RT not only improves survival and reduces toxicity compared with PF but also seems to improve global HRQOL in a more sustainable manner

    Response of zircon to melting and metamorphism in deep arc crust, Fiordland (New Zealand): implications for zircon inheritance in cordilleran granites

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    The Cretaceous Mount Daniel Complex (MDC) in northern Fiordland, New Zealand was emplaced as a 50 m-thick dyke and sheet complex into an active shear zone at the base of a Cordilleran magmatic arc. It was emplaced below the 20–25 km-thick, 125.3 ± 1.3 Ma old Western Fiordland Orthogneiss (WFO) and is characterized by metre-scale sheets of sodic, low and high Sr/Y diorites and granites. 119.3 ± 1.2 Ma old, pre-MDC lattice dykes and 117.4 ± 3.1 Ma late-MDC lattice dykes constrain the age of the MDC itself. Most dykes were isoclinally folded as they intruded, but crystallised within this deep-crustal, magma-transfer zone as the terrain cooled and was buried from 25 to 50 km (9–14 kbar), based on published P-T estimated from the surrounding country rocks. Zircon grains formed under these magmatic/granulite facies metamorphic conditions were initially characterized by conservatively assigning zircons with oscillatory zoning as igneous and featureless rims as metamorphic, representing 54% of the analysed grains. Further petrological assignment involved additional parameters such as age, morphology, Th/U ratios, REE patterns and Ti-in-zircon temperature estimates. Using this integrative approach, assignment of analysed grains to metamorphic or igneous groupings improved to 98%. A striking feature of the MDC is that only ~ 2% of all igneous zircon grains reflect emplacement, so that the zircon cargo was almost entirely inherited, even in dioritic magmas. Metamorphic zircons of MDC show a cooler temperature range of 740–640 °C, reflects the moderate ambient temperature of the lower crust during MDC emplacement. The MDC also provides a cautionary tale: in the absence of robust field and microstructural relations, the igneous-zoned zircon population at 122.1 ± 1.3 Ma, derived mostly from inherited zircons of the WFO, would be meaningless in terms of actual magmatic emplacement age of MDC, where the latter is further obscured by younger (ca. 114 Ma) metamorphic overgrowths. Thus, our integrative approach provides the opportunity to discriminate between igneous and metamorphic zircon within deep-crustal complexes. Also, without the tight field relations at Mt Daniel, the scatter beyond a statistically coherent group might be ascribed to the presence of “antecrysts�, but it is clear that the WFO solidified before the MDC was emplaced, and these older “igneous� grains are inherited. The bimodal age range of inherited igneous grains, dominated by ~ 125 Ma and 350–320 Ma age clusters, indicate that the adjacent WFO and a Carboniferous metaigneous basement were the main sources of the MDC magmas. Mafic lenses, stretched and highly attenuated into wisps within the MDC and dominated by ~ 124 Ma inherited zircons, are considered to be entrained restitic material from the WFO. A comparison with lower- and upper-crustal, high Sr/Y metaluminous granites elsewhere in Fiordland shows that zircon inheritance is common in the deep crust, near the source region, but generally much less so in coeval, shallow magma chambers (plutons). This is consistent with previous modelling on rapid zircon dissolution rates and high Zr saturation concentrations in metaluminous magmas. Accordingly, unless unusual circumstances exist, such as MDC preservation in the deep crust, low temperatures of magma generation, or rapid emplacement and crystallization at higher structural levels, information on zircon inheritance in upper crustal, Cordilleran plutons is lost during zircon dissolution, along with information on the age, nature and variety of the source material. The observation that dioritic magmas can form at these low temperatures ( < 750 °C) also suggests that the petrogenesis of mafic rocks in the arc root might need to be re-assessed

    Impacto financiero en la empresa Cerámicos Lambayeque SAC a través de la correlación de su economic value added y el crédito hipotecario del departamento de Lambayeque, en los periodos 2013-2012

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    La presente investigación tiene como objetivo principal evaluar el impacto financiero a través de la correlación estadística del crédito hipotecario y el economic value added (EVA) de Cerámicos Lambayeque SAC en los periodos 2013 -2012, para lograr ello se estableció las siguientes etapas de planificación tales como : Etapa 1: Se ha recolectado datos estadísticos sobre la evolución de los créditos hipotecarios en el departamento de Lambayeque (2013-2012). Etapa 2: Se determinó la cuota en el mercado de Cerámicos Lambayeque SAC en la región a través del nivel de producción mensual con respecto a sus competidores. Etapa 3: Se estableció la participación de Cerámicos Lambayeque SAC en los créditos hipotecarios en los periodos de análisis, contando con el nivel promedio de incidencia de ladrillo en los fines del crédito hipotecario a través del informe de Fondo Mivienda. Etapa 4: Se solicitó la información económica-financiera al área de contabilidad de la empresa Cerámicos Lambayeque SAC de los periodos 2013-2012. Etapa 5: Se calculó el rendimiento económico (ROA), el costo promedio ponderado de capital, rendimiento financiero (ROE) y el valor económico agregado (EVA). Etapa 6: Se determinó y analizó la correlación estadística anexando las variables de estudio; y en la Etapa 7: Se evaluó resultados estadísticos y se procedió a enumerar las conclusiones significativas y recomendaciones Los resultados, conclusiones y recomendaciones ha sido de beneficio para la junta de accionistas, gerente administrativo, contador y todos los demás stakeholders (partes interesadas) de la empresa. Asimismo tendrá una repercusión en el sector construcción, para las medidas financieras correspondientes.Tesi
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