987 resultados para Montezuma II, Emperor of Mexico, approximately 1480-1520


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BACKGROUND: To compare clinical and demographic data between laryngeal cancer patients younger and older than 40 years old. METHODS: Is a matched-paired study, realized from 1989 to 2002. We selected 500 laryngeal cancer patients treated in the National Cancer Institute of Mexico. Fifteen cases of patients younger than 40 years that accomplished inclusion criteria were identified, pair-matched and compared by clinical stage with 33 patients older than 40 years. We analyzed demographic factors and disease-free and Overall Survival by Kaplan-Meier method. RESULTS: We included 9 male and 6 female patients with a mean age of 34 years in contrast to a mean age of 62 years in the comparison group. Four cases in clinical stage I, none clinical stage II, 6 in stage III and 5 in stage IV were included in the younger group and compared to 8 patients in stage I, 15 in stage III and 10 in stage IV in the older group. No differences in demographic variables or lifestyle habits were found. All patients in stage I, are alive in both groups. Disease-free survival not show any differences when comparing stages III and IV (p=NS). Mean disease-free survival was 66 months and mean overall survival was 83 months in the younger group. CONCLUSION: Laryngeal carcinoma is rare in patients younger than 40 years. No gender, clinical or prognostic differences could be identified among the two groups. The prognosis of these patients seems to be only determined by the initial clinical stage.

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Non-Hodgkin's lymphoma (NHL) comprises both indolent forms, including follicular lymphoma (FL) and marginal zone lymphoma (MZL), and aggressive forms, including diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL). FL and DLBCL are the most common subtypes of indolent and aggressive NHL, respectively. Although these lymphomas exhibit different clinical behaviors and outcomes, the prognosis is negatively affected in both DLBCL and FL by the lack of a complete response (CR) with standard treatment options. The aim of therapy should therefore be achievement of a CR, which is not only associated with longer progression-free survival (PFS) and overall survival times, but is also a prerequisite for a cure, particularly in DLBCL. Consolidation treatment with radioimmunotherapy (RIT) is an innovative treatment approach to increase CR rates. Phase II studies have indicated promising results with yttrium-90 ((90)Y)-ibritumomab tiuxetan and iodine-131 ((131)I)-tositumomab as consolidation following induction therapy for previously untreated patients with advanced FL. More recently, investigators reported a marked increase in CR rates and significant improvements in PFS using standard chemotherapy regimens followed by (90)Y-ibritumomab tiuxetan in a phase III randomized trial in patients with previously untreated FL. Data also suggest that RIT may play a role in the treatment of high-risk DLBCL, with encouraging PFS results from a phase II trial of (90)Y-ibritumomab tiuxetan consolidation following induction with rituximab plus chemotherapy in elderly patients with previously untreated DLBCL. With the higher CR rates and longer PFS times observed in patients with FL and DLBCL, as well as encouraging early data from MZL and MCL consolidation trials, RIT appears to have an important role in the treatment of patients with NHL.

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This paper presents the segmentation of bilateral parotid glands in the Head and Neck (H&N) CT images using an active contour based atlas registration. We compare segmentation results from three atlas selection strategies: (i) selection of "single-most-similar" atlas for each image to be segmented, (ii) fusion of segmentation results from multiple atlases using STAPLE, and (iii) fusion of segmentation results using majority voting. Among these three approaches, fusion using majority voting provided the best results. Finally, we present a detailed evaluation on a dataset of eight images (provided as a part of H&N auto segmentation challenge conducted in conjunction with MICCAI-2010 conference) using majority voting strategy.

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Special Points of Interest: • The Division of Soil Conservation celebrated its 70th anniversary July 1, 2009. The Iowa Soil Conservation Laws were enacted in 1939 creating the state soil conservation agency and governing committee and providing for the creation of Iowa’s 100 soil and water conservation districts. • The Mines & Minerals Bureau, through the federal Abandoned Mine Land (AML) Program, worked with various watershed groups to again secure an additional $1 million dollars in funding for the construction on projects in Marion, Mahaska and Monroe Counties. • Iowa hosted the Mississippi River/Gulf of Mexico Hypoxia Task Force tour and meeting in September 2009.

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We consider damage spreading transitions in the framework of mode-coupling theory. This theory describes relaxation processes in glasses in the mean-field approximation which are known to be characterized by the presence of an exponentially large number of metastable states. For systems evolving under identical but arbitrarily correlated noises, we demonstrate that there exists a critical temperature T0 which separates two different dynamical regimes depending on whether damage spreads or not in the asymptotic long-time limit. This transition exists for generic noise correlations such that the zero damage solution is stable at high temperatures, being minimal for maximal noise correlations. Although this dynamical transition depends on the type of noise correlations, we show that the asymptotic damage has the good properties of a dynamical order parameter, such as (i) independence of the initial damage; (ii) independence of the class of initial condition; and (iii) stability of the transition in the presence of asymmetric interactions which violate detailed balance. For maximally correlated noises we suggest that damage spreading occurs due to the presence of a divergent number of saddle points (as well as metastable states) in the thermodynamic limit consequence of the ruggedness of the free-energy landscape which characterizes the glassy state. These results are then compared to extensive numerical simulations of a mean-field glass model (the Bernasconi model) with Monte Carlo heat-bath dynamics. The freedom of choosing arbitrary noise correlations for Langevin dynamics makes damage spreading an interesting tool to probe the ruggedness of the configurational landscape.

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The purpose of this review and analysis is to provide a basic understanding of the issues related to worldwide hypoxic zones and the range of economic questions sorely in need of answers. We begin by describing the causes and extent of hypoxic zones worldwide, followed by a review of the evidence concerning ecological effects of the condition and impacts on ecosystem services. We describe what is known about abatement options and cost effective policy design before turning to an analysis of the large, seasonally recurring hypoxic zone in the Gulf of Mexico. We advance the understanding of this major ecological issue by estimating the relationship between pollutants (nutrients) and the areal extent of the hypoxic zone. This “production function” relationship suggests that both instantaneous and legacy contributions of nutrients contribute to annual predictions of the size of the zone, highlighting concerns that ecologists have raised about lags in the recovery of the system and affirms the importance of multiple nutrients as target pollutants. We conclude with a discussion of critical research needs to provide input to policy formation.

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INTRODUCTION: Video records are widely used to analyze performance in alpine skiing at professional or amateur level. Parts of these analyses require the labeling of some movements (i.e. determining when specific events occur). If differences among coaches and differences for the same coach between different dates are expected, they have never been quantified. Moreover, knowing these differences is essential to determine which parameters reliable should be used. This study aimed to quantify the precision and the repeatability for alpine skiing coaches of various levels, as it is done in other fields (Koo et al, 2005). METHODS: A software similar to commercialized products was designed to allow video analyses. 15 coaches divided into 3 groups (5 amateur coaches (G1), 5 professional instructors (G2) and 5 semi-professional coaches (G3)) were enrolled. They were asked to label 15 timing parameters (TP) according to the Swiss ski manual (Terribilini et al, 2001) for each curve. TP included phases (initiation, steering I-II), body and ski movements (e.g. rotation, weighting, extension, balance). Three video sequences sampled at 25 Hz were used and one curve per video was labeled. The first video was used to familiarize the analyzer to the software. The two other videos, corresponding to slalom and giant slalom, were considered for the analysis. G1 realized twice the analysis (A1 and A2) at different dates and TP were randomized between both analyses. Reference TP were considered as the median of G2 and G3 at A1. The precision was defined as the RMS difference between individual TP and reference TP, whereas the repeatability was calculated as the RMS difference between individual TP at A1 and at A2. RESULTS AND DISCUSSION: For G1, G2 and G3, a precision of +/-5.6 frames, +/-3.0 and +/-2.0 frames, was respectively obtained. These results showed that G2 was more precise than G1, and G3 more precise than G2, were in accordance with group levels. The repeatability for G1 was +/-3.1 frames. Furthermore, differences among TP precision were observed, considering G2 and G3, with largest differences of +/-5.9 frames for "body counter rotation movement in steering phase II", and of 0.8 frame for "ski unweighting in initiation phase". CONCLUSION: This study quantified coach ability to label video in term of precision and repeatability. The best precision was obtained for G3 and was of +/-0.08s, which corresponds to +/-6.5% of the curve cycle. Regarding the repeatability, we obtained a result of +/-0.12s for G1, corresponding to +/-12% of the curve cycle. The repeatability of G2 and G3 are expected to be lower than the precision of G1 and the corresponding repeatability will be assessed soon. In conclusion, our results indicate that the labeling of video records is reliable for some TP, whereas caution is required for others. REFERENCES Koo S, Gold MD, Andriacchi TP. (2005). Osteoarthritis, 13, 782-789. Terribilini M, et al. (2001). Swiss Ski manual, 29-46. IASS, Lucerne.

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Lake Geneva is one of the largest European lakes with a surface area of 580 km2. Its catchment area covers 7400 km2, of which approximately 20% is arable land. Monitoring campaigns have been carried out in 2004 and 2005 to determine the contamination of the lake by pesticides. The results highlight the widespread presence of herbicides in water, the measured concentrations for most substances remaining constant in 2004 and 2005. However, for some individual herbicides the concentrations increased drastically (e.g., the herbicide foramsulfuron). We assessed the environmental risk of the herbicides detected in the lake using water quality criteria recently determined for the Swiss environmental protection agency. Furthermore, we assessed the risk of herbicide mixtures, grouped based upon their mode of action. Generally, the risk estimated for all single substances is low, except for some sulfonylurea compounds. For these substances, the measured concentrations are higher than the predicted no-effect concentration. Impact on the flora of the lake can therefore not be excluded. When mixtures of pesticides with similar mode of action are taken into account, the risk remains lower than the mixture water quality criteria for all groups, but can reach as high as one third of this quality criteria. A further step would therefore be to assess the risk of the total pesticide mixture, including similar and dissimilar modes of action.

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The calcitonin receptor-like receptor (CRLR) and receptor activity modifying protein-3 (RAMP3) can assemble into a CRLR/RAMP3 heterodimeric receptor that exhibits the characteristics of a high affinity adrenomedullin receptor. RAMP3 participates in adrenomedullin (AM) binding via its extracellular N-terminus characterized by the presence of six highly conserved cysteine residues and four N-glycosylation consensus sites. Here, we assessed the usage of these conserved residues in cotranslational modifications of RAMP3 and addressed their role in functional expression of the CRLR/RAMP3 receptor. Using a Xenopus oocyte expression system, we show that (i) RAMP3 is assembled with CRLR as a multiple N-glycosylated species in which two, three, or four consensus sites are used; (ii) elimination of all N-glycans in RAMP3 results in a significant inhibition of receptor [(125)I]AM binding and an increase in the EC(50) value for AM; (iii) several lines of indirect evidence indicate that each of the six cysteines is involved in disulfide bond formation; (iv) when all cysteines are mutated to serines, RAMP3 is N-glycosylated at all four consensus sites, suggesting that disulfide bond formation inhibits N-gylcosylation; and (v) elimination of all cysteines abolishes adrenomedullin binding and leads to a complete loss of receptor function. Our data demonstrate that cotranslational modifications of RAMP3 play a critical role in the function of the CRLR/RAMP3 adrenomedullin receptor.

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BACKGROUND: Prognostic models and nomograms were recently developed to predict survival of patients with newly diagnosed glioblastoma multiforme (GBM).1 To improve predictions, models should be updated with the most recent patient and disease information. Nomograms predicting patient outcome at the time of disease progression are required. METHODS: Baseline information from 299 patients with recurrent GBM recruited in 8 phase I or II trials of the EORTC Brain Tumor Group was used to evaluate clinical parameters as prognosticators of patient outcome. Univariate (log rank) and multivariate (Cox models) analyses were made to assess the ability of patients' characteristics (age, sex, performance status [WHO PS], and MRC neurological deficit scale), disease history (prior treatments, time since last treatment or initial diagnosis, and administration of steroids or antiepileptics) and disease characteristics (tumor size and number of lesions) to predict progression free survival (PFS) and overall survival (OS). Bootstrap technique was used for models internal validation. Nomograms were computed to provide individual patients predictions. RESULTS: Poor PS and more than 1 lesion had a significant prognostic impact for both PFS and OS. Antiepileptic drug use was significantly associated with worse PFS. Larger tumors (split by the median of the largest tumor diameter >42.5 mm) and steroid use had shorter OS. Age, sex, neurologic deficit, prior therapies, and time since last therapy or initial diagnosis did not show independent prognostic value for PFS or OS. CONCLUSIONS: This analysis confirms that PS but not age is a major prognostic factor for PFS and OS. Multiple or large tumors and the need to administer steroids significantly increase the risk of progression and death. Nomograms at the recurrence could be used to obtain accurate predictions for the design of new targeted therapy trials or retrospective analyses. (1. T. Gorlia et al., Nomograms for predicting survival of patients with newly diagnosed glioblastoma. Lancet Oncol 9 (1): 29-38, 2008.)

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Rupture of vulnerable plaques is the main cause of acute cardiovascular events. However, mechanisms responsible for transforming a stable into a vulnerable plaque remain elusive. Angiotensin II, a key regulator of blood pressure homeostasis, has a potential role in atherosclerosis. To study the contribution of angiotensin II in plaque vulnerability, we generated hypertensive hypercholesterolemic ApoE-/- mice with either normal or endogenously increased angiotensin II production (renovascular hypertension models). Hypertensive high angiotensin II ApoE-/- mice developed unstable plaques, whereas in hypertensive normal angiotensin II ApoE-/- mice plaques showed a stable phenotype. Vulnerable plaques from high angiotensin II ApoE-/- mice had thinner fibrous cap (P<0.01), larger lipid core (P<0.01), and increased macrophage content (P<0.01) than even more hypertensive but normal angiotensin II ApoE-/- mice. Moreover, in mice with high angiotensin II, a skewed T helper type 1-like phenotype was observed. Splenocytes from high angiotensin II ApoE-/- mice produced significantly higher amounts of interferon (IFN)-gamma than those from ApoE-/- mice with normal angiotensin II; secretion of IL4 and IL10 was not different. In addition, we provide evidence for a direct stimulating effect of angiotensin II on lymphocyte IFN-gamma production. These findings suggest a new mechanism in plaque vulnerability demonstrating that angiotensin II, within the context of hypertension and hypercholesterolemia, independently from its hemodynamic effect behaves as a local modulator promoting the induction of vulnerable plaques probably via a T helper switch.

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1. Few examples of habitat-modelling studies of rare and endangered species exist in the literature, although from a conservation perspective predicting their distribution would prove particularly useful. Paucity of data and lack of valid absences are the probable reasons for this shortcoming. Analytic solutions to accommodate the lack of absence include the ecological niche factor analysis (ENFA) and the use of generalized linear models (GLM) with simulated pseudo-absences. 2. In this study we tested a new approach to generating pseudo-absences, based on a preliminary ENFA habitat suitability (HS) map, for the endangered species Eryngium alpinum. This method of generating pseudo-absences was compared with two others: (i) use of a GLM with pseudo-absences generated totally at random, and (ii) use of an ENFA only. 3. The influence of two different spatial resolutions (i.e. grain) was also assessed for tackling the dilemma of quality (grain) vs. quantity (number of occurrences). Each combination of the three above-mentioned methods with the two grains generated a distinct HS map. 4. Four evaluation measures were used for comparing these HS maps: total deviance explained, best kappa, Gini coefficient and minimal predicted area (MPA). The last is a new evaluation criterion proposed in this study. 5. Results showed that (i) GLM models using ENFA-weighted pseudo-absence provide better results, except for the MPA value, and that (ii) quality (spatial resolution and locational accuracy) of the data appears to be more important than quantity (number of occurrences). Furthermore, the proposed MPA value is suggested as a useful measure of model evaluation when used to complement classical statistical measures. 6. Synthesis and applications. We suggest that the use of ENFA-weighted pseudo-absence is a possible way to enhance the quality of GLM-based potential distribution maps and that data quality (i.e. spatial resolution) prevails over quantity (i.e. number of data). Increased accuracy of potential distribution maps could help to define better suitable areas for species protection and reintroduction.

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Abstract Human experience takes place in the line of mental time (MT) created through 'self-projection' of oneself to different time-points in the past or future. Here we manipulated self-projection in MT not only with respect to one's life events but also with respect to one's faces from different past and future time-points. Behavioural and event-related functional magnetic resonance imaging activity showed three independent effects characterized by (i) similarity between past recollection and future imagination, (ii) facilitation of judgements related to the future as compared with the past, and (iii) facilitation of judgements related to time-points distant from the present. These effects were found with respect to faces and events, and also suggest that brain mechanisms of MT are independent of whether actual life episodes have to be re-experienced or pre-experienced, recruiting a common cerebral network including the anteromedial temporal, posterior parietal, inferior frontal, temporo-parietal and insular cortices. These behavioural and neural data suggest that self-projection in time is a fundamental aspect of MT, relying on neural structures encoding memory, mental imagery and self.

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U.S. Highway 61 between Muscatine and Davenport, Iowa, is a four-lane divided section of road approximately 21 miles in length. This section was found to be among the top 5% of Iowa roadways for single-vehicle run-off-road, impaired driver, unbelted driver, and speed-related crashes for the period of 2001 through 2005. A road safety audit of this corridor was deemed appropriate by the Iowa Department of Transportation’s Office of Traffic and Safety. Staff and officials from the Iowa Department of Transportation (Iowa DOT), Iowa State Patrol, Governor’s Traffic Safety Bureau, Federal Highway Administration, Center for Transportation Research and Education, and several local law enforcement and transportation agencies met to review crash data and discuss potential safety improvements to US 61. This report outlines the findings and recommendations of the road safety audit team to address the safety concerns on this US 61 corridor and explains several selected mitigation strategies.

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Of the approximately 25,000 bridges in Iowa, 28% are classified as structurally deficient, functionally obsolete, or both. The state of Iowa thus follows the national trend of an aging infrastructure in dire need of repair or replacement with a relatively limited funding base. Therefore, there is a need to develop new materials with properties that may lead to longer life spans and reduced life-cycle costs. In addition, new methods for determining the condition of structures are needed to monitor the structures effectively and identify when the useful life of the structure has expired or other maintenance is needed. High-performance steel (HPS) has emerged as a material with enhanced weldability, weathering capabilities, and fracture toughness compared to conventional structural steels. In 2004, the Iowa Department of Transportation opened Iowa's first HPS girder bridge, the East 12th Street Bridge over I-235 in Des Moines, Iowa. The objective of this project was to evaluate HPS as a viable option for use in Iowa bridges with a continuous structural health monitoring (SHM) system. The scope of the project included documenting the construction of the East 12th Street Bridge and concurrently developing a remote, continuous SHM system using fiber-optic sensing technology to evaluate the structural performance of the bridge. The SHM system included bridge evaluation parameters, similar to design parameters used by bridge engineers, for evaluating the structure. Through the successful completion of this project, a baseline of bridge performance was established that can be used for continued long-term monitoring of the structure. In general, the structural performance of the HPS bridge exceeded the design parameters and is performing well. Although some problems were encountered with the SHM system, the system functions well and recommendations for improving the system have been made.