Description: The observed acceleration of glaciers from West Antarctica into the Amundsen Sea is estimated to be contributing 6% to current sea-level rise with the estimated potential to add 0.24 m to global sea level. Stronger westerly winds over the Amundsen Sea can increase the flow of relatively warm ocean water to the base of ice shelves that flow from glaciers into the Amundsen Sea. Thinning of the glaciers caused by this warming is a potentially important factor in driving the observed acceleration of glaciers. However, the climatology of winds in the region has not been extensively studied due to a lack of in situ observational long-term records. Here six different reanalysis datasets are assessed (CFSR, ERA-40, ERA-Interim, JRA-25, MERRA and NNR1) to determine a best estimate of variability and change since 1979 when the widespread monitoring of the atmosphere from satellites was introduced. A comparison with independent mean sea-level pressure data from ice drifting buoys shows that ERA-Interim is clearly the most accurate at capturing the details of individual weather systems over the neighbouring Bellingshausen Sea, implying that it is also accurate over the Amundsen Sea. In terms of climatological means, the five recently-produced (after ∼2000) reanalysis datasets show only small differences. Decadal variations of westerly winds congruent with the observed increases in the southern annular mode (SAM) index are a consistent feature across the reanalysis datasets. In particular, the strong seasonal dependence of observed trends in the SAM (i.e. significant positive trends in the summer and autumn in recent decades) is also seen in the strength of westerly winds over the Amundsen Sea. In terms of year-to-year variability, the annual mean westerly winds over the Amundsen Sea were found to be significantly correlated with the SAM in summer ( r = 0.35; p ≤0.05) and El Nino-Southern Oscillation in spring (September to November) ( r = 0.41; p ≤0.05). Copyright © 2012 Royal Meteorological Society

Description: Idealized models and a simple vertically averaged vorticity equation illustrate the effects of an upwelling favorable wind and a spatially variable landfast ice cover on the circulation beneath landfast ice. For the case of no along-shore variations in ice, upwelling favorable winds seaward of the ice edge result in vortex squashing beneath the landfast ice leading to (1) large decreases in coastal and ice edge sea levels, (2) cross-shore sea level slopes and weak (

Description: ABSTRACT This paper presents a three-dimensional energy-based solution for the time-dependent response of a deeply embedded and unsupported semi-infinite tunnel of circular cross-section. The tunnel is taken to be excavated quasi-instantaneously from an infinite rock body that initially exhibits an isotropic stress state and that is made up of a homogeneous, isotropic and viscoelastic material. The viscoelastic behaviour is modelled by means of Burger's model, and the rock is taken to behave volumetrically linear elastic and to exhibit exclusively deviatoric creep. This viscoelastic problem is transformed into the Laplace domain, where it represents a quasi-elastic problem. The displacement fields in the new solution are taken to be the products of independent functions that vary in the radial and longitudinal directions. The differential equations governing the displacements of the system and appropriate boundary conditions are obtained using the principle of minimum potential energy. The solutions for these governing equations in the Laplace domain are then obtained analytically and numerically using a one-dimensional finite difference technique. The results are then transformed back into the time domain using an efficient numerical scheme. The accuracy of the new solution is comparable with that of a finite element analysis but requires much less computation effort. Copyright © 2011 John Wiley & Sons, Ltd.

Description: The aims of the study were to evaluate therapeutic efficacy and to determine the prognostic factors for treatment success in patients with liver metastases from CRC treated with transarterial chemoembolization (TACE). A total of 564 patients (mean age, 60.3 years) with liver metastases of CRC were repeatedly treated with TACE. In total, 3384 TACE-procedures were performed (mean, 6 sessions per patient). The local chemotherapy protocol consisted of mitomycin C alone (43.1%), mitomycin C with gemcitabine (27.1%), mitomycin C with irinotecan (15.6%), or mitomycin C with irinotecan and cisplatin (15.6%). Embolization was performed with lipiodol and starch microspheres. Tumor response was evaluated with MRI or CT. The change in tumor size was calculated and the response was evaluated according to the RECIST-Criteria. Survival rates were calculated according to the Kaplan-Meier method. Prognostic factors for patient's survival were evaluated using log-rank-test. Evaluation of local tumor control showed partial response in 16.7%, stable disease in 48.2%, and progressive disease 16.7%. The 1-year survival rate after chemoembolization was 62%, the 2-year survival rate was 28%, and the 3-year survival rate was 7%. Median survival from the start of chemoembolization treatment was 14.3 months. The indication (p=0.001) and initial tumor response (p=0.015) were statistically significant factors for patient's survival. TACE is a minimally-invasive therapy option for controlling local metastases and improving survival time in patients with hepatic metastases from CRC. TN stage, extrahepatic metastases, number of lesions, tumor location within the liver and choice of chemotherapy protocol of TACE are none significant factors for patient's survival. © 2013 Wiley Periodicals, Inc.

Description: BACKGROUND With the advent of widespread prostate-specific antigen (PSA) testing in recent decades, prostate cancer (PCa) has emerged as the most frequently diagnosed non-skin cancer among men in the U.S. and Europe [1]. Greater screening rates coupled with improved detection methods have caused a controversial upsurge in the number of men undergoing prostate biopsy and subsequent treatment. However, current diagnostic techniques generally suffer from limited ability to identify which seemingly indolent cancers are biologically aggressive [2]. METHODS We collected prostatic fluid from 778 post-radical prostatectomy specimens and randomly selected samples from both the clinically confirmed aggressive (n = 50) and non-aggressive (n = 50) prostate cancer populations. We measured the level of proteolytic enzyme activity of PSA (aPSA) in each sample and used receiver operating characteristic (ROC) analysis to correlate aPSA levels with prostate cancer aggressiveness. RESULTS We found aPSA in prostatic fluid to be inversely proportional to disease stage, such that patients with the most aggressive PCa have on average significantly reduced aPSA compared to those with less aggressive disease. Significantly, our results suggest that many (22% in our study population) of the diagnosed patients with non-aggressive PCa could have averted or delayed radical prostatectomy. CONCLUSIONS Given the high level of debate surrounding PSA screening effectiveness [3–5] and the recent U.S. Preventative Services Task Force recommendation to discontinue PSA screening [6], our results provide renewed hope that a clinical monitoring tool may emerge that truly refines PCa treatment decision-making. Prostate 9999: 1–7, 2013 . © 2013 Wiley Periodicals, Inc.

Description: Ecological Applications, Volume 23, Issue 4, Page 879-887, June 2013. Declines of migratory birds have led to increased focus on causative factors for these declines, including the potential adverse effects of habitat fragmentation on reproductive success. Although numerous studies have addressed how proximity to a habitat edge, patch size, or landscape context influence nest survival or brood parasitism, many have failed to find the purported effects. Furthermore, many have sought to generalize patterns across large geographic areas and habitats. Here, we examined evidence for effects of edge proximity, patch size, and landscape context on nest survival and brood parasitism of grassland birds, a group of conservation concern. The only consistent effect was a positive association between edge proximity and brood parasitism. We examined effects of patch size on nest survival (37 studies) and brood parasitism (30 studies) representing 170 and 97 different estimates, respectively, with a total sample size of 〉14 000 nests spanning eastern North America. Nest survival weakly increased with patch size in the Great Plains, but not in the Midwestern or Eastern United States, and brood parasitism was inversely related to patch size and consistently greater in the Great Plains. The consistency in brood parasitism relative to nest survival patterns is likely due to parasitism being caused by one species, while nest survival is driven by a diverse and variable suite of nest predators. Often, studies assume that predators responsible for nest predation, the main driver of nest success, either are the same or exhibit the same behaviors across large geographic areas. These results suggest that a better mechanistic understanding of nest predation is needed to provide meaningful conservation recommendations for improving grassland bird productivity, and that the use of general recommendations across large geographic areas should only be undertaken when sufficient data are available from all regions.

Description: Question Plant communities are not necessarily spatially exclusive; a point in space can exhibit properties of multiple communities. Such variation can be described using floristically defined ‘fuzzy’ units, however these may not be easily delineated using standard remote sensing methods. Is there value in considering communities as fuzzy? Can species distribution modelling methods be used to represent fuzzy communities spatially? Location Western Victoria, Australia. Methods Fuzzy communities were objectively identified from vegetation census quadrats with a cluster analysis of ordinated species data. Boosted regression trees were used to create models that defined relationships between the sampled communities and environmental predictor variables. These were applied to the mapped predictors to create maps of estimated fuzzy community membership for the entire study area. Results Four separate fuzzy communities were identified from the sampled vegetation data. Models were created for each community and these were effectively used to generate maps of fuzzy community membership. Individual fuzzy community maps illustrated vegetation variation that could not be discerned on a discretely classified map. Conclusions Fuzzy communities were found to represent a greater proportion of species variation than discretely classified units. Species distribution modelling methods were effective in creating independent spatial maps of each floristically defined fuzzy community; however the interpretation of these maps is more complex than with a single discrete community map. Maps of fuzzy community properties are an alternative to discrete community maps. Due to their non-exclusive nature, such communities are not easily delineated through traditional means. Boosted regression tree modelling using biophysical predictor variables, an approach more commonly found in species distribution modelling, was evaluated and found to have potential for creating fuzzy community maps.

Description: ABSTRACT In this study, a synoptic climatological approach is employed to assess the relationship between the frequency of circulation patterns (CPs) and the latitude of mid-September sea ice minima in the western Arctic. Fifteen CPs are created via principal component analysis and cluster analysis from daily NCEP/NCAR reanalysis sea-level pressure (SLP) fields across a grid from 50 to 90°N and 150°E–100°W from 1979 to 2011. The frequency of these CPs are statistically compared with the latitude of the sea ice minimum from passive microwave data for each of 11 equally-spaced longitudes (176°W to 126°W) extending into the Chukchi and Beaufort Seas. Monthly frequencies for each of the 15 CPs from March to September, signifying the melt season, for each year are correlated with the ice minimum for that September. These monthly frequencies are then entered into a stepwise multiple linear regression (SMLR) and collectively, CP frequencies explain 40–79% of the total ice retreat variance across the longitudes. The frequency of one cluster, CP 11, representing a broad high pressure area over the Beaufort Sea, is highly correlated with the latitude of the sea ice minima; June and August frequencies of this pattern are the initial predictors at 8 of the 11 longitudes and explain 22–32% of the variance. This pattern has occurred more frequently from 2007 onwards; compared with a June mean occurrence of 9 days during 1979–2006, CP 11 occurred 16 times in June 2007, and on average more than 17 days per month during June 2008–2011. The Arctic Dipole (AD), Arctic Oscillation (AO), and Pacific-North American (PNA) pattern indices are significantly correlated with CPs 11–13 frequencies throughout certain summer months, further indicating strong relationships between summer circulation and sea ice minima in the region.

Description: Paleoindian sites in eastern South America are generally found inside rock-shelters. Recently, we designed a program to find open-air Paleoindian sites in the Lagoa Santa region of Brazil. Here, we present data gathered at Sumidouro site, a multicomponent site with a Paleoindian horizon, detected on a shoreline slope of Sumidouro Lake, Minas Gerais State. We present a model for late Pleistocene/Holocene slope evolution that suggests at least three different episodes of instability (erosion/sedimentation) followed by periods of stability (pedogenesis). Higher soil accretion rates during the Mid-Holocene are probably not linked to a stable dry climate, but to greater climatic instability. We also found that the position of both archaeological materials and charcoal can be explained by burial of ancient surfaces and are not the result of downslope movement. The role of bioturbation in the vertical displacement of such materials is much less important than previously acknowledged.