978 resultados para 13077-065


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Treelines are expected to rise to higher elevations with climate warming; the rate and extent however are still largely unknown. Here we present the first multi-proxy palaeoecological study from the treeline in the Northwestern Swiss Alps that covers the entire Holocene. We reconstructed climate, fire and vegetation dynamics at Iffigsee, an alpine lake at 2,065 m a.s.l., by using seismic sedimentary surveys, loss on ignition, visible spectrum reflectance spectroscopy, pollen, spore, macrofossil and charcoal analyses. Afforestation with Larix decidua and tree Betula (probably B. pendula) started at ~9,800 cal. b.p., more than 1,000 years later than at similar elevations in the Central and Southern Alps, indicating cooler temperatures and/or a high seasonality. Highest biomass production and forest position of ~2,100–2,300 m a.s.l. are inferred during the Holocene Thermal Maximum from 7,000 to 5,000 cal. b.p. With the onset of pastoralism and transhumance at 6,800–6,500 cal. b.p., human impact became an important factor in the vegetation dynamics at Iffigsee. This early evidence of pastoralism is documented by the presence of grazing indicators (pollen, spores), as well as a wealth of archaeological finds at the nearby mountain pass of Schnidejoch. Human and fire impact during the Neolithic and Bronze Ages led to the establishment of pastures and facilitated the expansion of Picea abies and Alnus viridis. We expect that in mountain areas with land abandonment, the treeline will react quickly to future climate warming by shifting to higher elevations, causing drastic changes in species distribution and composition as well as severe biodiversity losses.

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AIMS Cystatin C is a well established marker of kidney function. There is evidence that cystatin C concentrations are also associated with mortality. The present analysis prospectively evaluated the associations of cystatin C with all-cause and cardiovascular (CV) mortality in a well-characterized cohort of persons undergoing angiography, but without overt renal insufficiency. METHODS Cystatin C was available in 2998 persons (mean age: 62.7 ± 10.5 years; 30.3% women). Of those 2346 suffered from coronary artery disease (CAD) and 652 (controls) did not. Creatinine (mean ± SD: 83.1 ± 47.8 vs. 74.1 ± 24.7 μmol/L, p = 0.036) but not Cystatin C (mean ± SD: 1.02 ± 0.44 vs. 0.92 ± 0.26 mg/L, p = 0.065) was significantly higher in patients with CAD. After a median follow-up of 9.9 years, in total 898 (30%) deaths occurred, 554 (18.5%) due to CV disease and 326 (10.9%) due to non-CV causes. Multivariable-adjusted Cox analysis (adjusting for eGFR and established cardiovascular risk factors, lipid lowering therapy, angiographic coronary artery disease, and C-reactive protein) revealed that patients in the highest cystatin C quartile were at an increased risk for all-cause (hazard ratio (HR) 1.93, 95% CI 1.50-2.48) and CV mortality (HR 2.05 95% CI 1.48-2.84) compared to those in the lowest quartile. The addition of cystatin C to a model consisting of established cardiovascular risk factors increased the area under the receiver-operating characteristic curve for CV and all-cause mortality, but the difference was statistically not significant. However, reclassification analysis revealed significant improvement by addition of cystatin C for CV and all-cause mortality (p < 0.001), respectively. CONCLUSION The concentration of cystatin C is strongly associated with long-term all-cause and cardiovascular mortality in patients referred to coronary angiography, irrespective of creatinine-based renal function.

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BACKGROUND Trastuzumab has established efficacy against breast cancer with overexpression or amplification of the HER2 oncogene. The standard of care is 1 year of adjuvant trastuzumab, but the optimum duration of treatment is unknown. We compared 2 years of treatment with trastuzumab with 1 year of treatment, and updated the comparison of 1 year of trastuzumab versus observation at a median follow-up of 8 years, for patients enrolled in the HERceptin Adjuvant (HERA) trial. METHODS The HERA trial is an international, multicentre, randomised, open-label, phase 3 trial comparing treatment with trastuzumab for 1 and 2 years with observation after standard neoadjuvant chemotherapy, adjuvant chemotherapy, or both in 5102 patients with HER2-positive early breast cancer. The primary endpoint was disease-free survival. The comparison of 2 years versus 1 year of trastuzumab treatment involved a landmark analysis of 3105 patients who were disease-free 12 months after randomisation to one of the trastuzumab groups, and was planned after observing at least 725 disease-free survival events. The updated intention-to-treat comparison of 1 year trastuzumab treatment versus observation alone in 3399 patients at a median follow-up of 8 years (range 0-10) is also reported. This study is registered with ClinicalTrials.gov, number NCT00045032. FINDINGS We recorded 367 events of disease-free survival in 1552 patients in the 1 year group and 367 events in 1553 patients in the 2 year group (hazard ratio [HR] 0·99, 95% CI 0·85-1·14, p=0·86). Grade 3-4 adverse events and decreases in left ventricular ejection fraction during treatment were reported more frequently in the 2 year treatment group than in the 1 year group (342 [20·4%] vs 275 [16·3%] grade 3-4 adverse events, and 120 [7·2%] vs 69 [4·1%] decreases in left ventricular ejection fraction, respectively). HRs for a comparison of 1 year of trastuzumab treatment versus observation were 0·76 (95% CI 0·67-0·86, p<0·0001) for disease-free survival and 0·76 (0·65-0·88, p=0·0005) for overall survival, despite crossover of 884 (52%) patients from the observation group to trastuzumab therapy. INTERPRETATION 2 years of adjuvant trastuzumab is not more effective than is 1 year of treatment for patients with HER2-positive early breast cancer. 1 year of treatment provides a significant disease-free and overall survival benefit compared with observation and remains the standard of care. FUNDING F Hoffmann-La Roche (Roche).

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Music is an intriguing stimulus widely used in movies to increase the emotional experience. However, no brain imaging study has to date examined this enhancement effect using emotional pictures (the modality mostly used in emotion research) and musical excerpts. Therefore, we designed this functional magnetic resonance imaging study to explore how musical stimuli enhance the feeling of affective pictures. In a classical block design carefully controlling for habituation and order effects, we presented fearful and sad pictures (mostly taken from the IAPS) either alone or combined with congruent emotional musical excerpts (classical pieces). Subjective ratings clearly indicated that the emotional experience was markedly increased in the combined relative to the picture condition. Furthermore, using a second-level analysis and regions of interest approach, we observed a clear functional and structural dissociation between the combined and the picture condition. Besides increased activation in brain areas known to be involved in auditory as well as in neutral and emotional visual-auditory integration processes, the combined condition showed increased activation in many structures known to be involved in emotion processing (including for example amygdala, hippocampus, parahippocampus, insula, striatum, medial ventral frontal cortex, cerebellum, fusiform gyrus). In contrast, the picture condition only showed an activation increase in the cognitive part of the prefrontal cortex, mainly in the right dorsolateral prefrontal cortex. Based on these findings, we suggest that emotional pictures evoke a more cognitive mode of emotion perception, whereas congruent presentations of emotional visual and musical stimuli rather automatically evoke strong emotional feelings and experiences.

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A search is presented for new particles in an extension to the Standard Model that includes a heavy Higgs boson (H-0), an intermediate charged Higgs-boson pair (H-+/-), and a light Higgs boson (h(0)). The analysis searches for events involving the production of a single heavy neutral Higgs boson which decays to the charged Higgs boson and a W boson, where the charged Higgs boson subsequently decays into a W boson and the lightest neutral Higgs boson decaying to a bottom-antibottom-quark pair. Such a cascade results in a W-boson pair and a bottom-antibottom-quark pair in the final state. Events with exactly one lepton, missing transverse momentum, and at least four jets are selected from a data sample corresponding to an integrated luminosity of 20.3 fb(-1), collected by the ATLAS detector in proton-proton collisions at root s = 8 TeV at the LHC. The data are found to be consistent with Standard Model predictions, and 95% confidence-level upper limits are set on the product of cross section and branching ratio. These limits range from 0.065 to 43 pb as a function of H-0 and H-+/- masses, with m(h)o fixed at 125 GeV.

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BACKGROUND Clinical prognostic groupings for localised prostate cancers are imprecise, with 30-50% of patients recurring after image-guided radiotherapy or radical prostatectomy. We aimed to test combined genomic and microenvironmental indices in prostate cancer to improve risk stratification and complement clinical prognostic factors. METHODS We used DNA-based indices alone or in combination with intra-prostatic hypoxia measurements to develop four prognostic indices in 126 low-risk to intermediate-risk patients (Toronto cohort) who will receive image-guided radiotherapy. We validated these indices in two independent cohorts of 154 (Memorial Sloan Kettering Cancer Center cohort [MSKCC] cohort) and 117 (Cambridge cohort) radical prostatectomy specimens from low-risk to high-risk patients. We applied unsupervised and supervised machine learning techniques to the copy-number profiles of 126 pre-image-guided radiotherapy diagnostic biopsies to develop prognostic signatures. Our primary endpoint was the development of a set of prognostic measures capable of stratifying patients for risk of biochemical relapse 5 years after primary treatment. FINDINGS Biochemical relapse was associated with indices of tumour hypoxia, genomic instability, and genomic subtypes based on multivariate analyses. We identified four genomic subtypes for prostate cancer, which had different 5-year biochemical relapse-free survival. Genomic instability is prognostic for relapse in both image-guided radiotherapy (multivariate analysis hazard ratio [HR] 4·5 [95% CI 2·1-9·8]; p=0·00013; area under the receiver operator curve [AUC] 0·70 [95% CI 0·65-0·76]) and radical prostatectomy (4·0 [1·6-9·7]; p=0·0024; AUC 0·57 [0·52-0·61]) patients with prostate cancer, and its effect is magnified by intratumoral hypoxia (3·8 [1·2-12]; p=0·019; AUC 0·67 [0·61-0·73]). A novel 100-loci DNA signature accurately classified treatment outcome in the MSKCC low-risk to intermediate-risk cohort (multivariate analysis HR 6·1 [95% CI 2·0-19]; p=0·0015; AUC 0·74 [95% CI 0·65-0·83]). In the independent MSKCC and Cambridge cohorts, this signature identified low-risk to high-risk patients who were most likely to fail treatment within 18 months (combined cohorts multivariate analysis HR 2·9 [95% CI 1·4-6·0]; p=0·0039; AUC 0·68 [95% CI 0·63-0·73]), and was better at predicting biochemical relapse than 23 previously published RNA signatures. INTERPRETATION This is the first study of cancer outcome to integrate DNA-based and microenvironment-based failure indices to predict patient outcome. Patients exhibiting these aggressive features after biopsy should be entered into treatment intensification trials. FUNDING Movember Foundation, Prostate Cancer Canada, Ontario Institute for Cancer Research, Canadian Institute for Health Research, NIHR Cambridge Biomedical Research Centre, The University of Cambridge, Cancer Research UK, Cambridge Cancer Charity, Prostate Cancer UK, Hutchison Whampoa Limited, Terry Fox Research Institute, Princess Margaret Cancer Centre Foundation, PMH-Radiation Medicine Program Academic Enrichment Fund, Motorcycle Ride for Dad (Durham), Canadian Cancer Society.

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BACKGROUND No data exist on the patterns of biochemical recurrence (BCR) and their effect on survival in patients with high-risk prostate cancer (PCa) treated with surgery. The aim of our investigation was to evaluate the natural history of PCa in patients treated with radical prostatectomy (RP) alone. MATERIALS AND METHODS Overall, 2,065 patients with high-risk PCa treated with RP at 7 tertiary referral centers between 1991 and 2011 were identified. First, we calculated the probability of experiencing BCR after surgery. Particularly, we relied on conditional survival estimates for BCR after RP. Competing-risks regression analyses were then used to evaluate the effect of time to BCR on the risk of cancer-specific mortality (CSM). RESULTS Median follow-up was 70 months. Overall, the 5-year BCR-free survival rate was 55.2%. Given the BCR-free survivorship at 1, 2, 3, 4, and 5 years, the BCR-free survival rates improved by+7.6%,+4.1%,+4.8%,+3.2%, and+3.7%, respectively. Overall, the 10-year CSM rate was 14.8%. When patients were stratified according to time to BCR, patients experiencing BCR within 36 months from surgery had higher 10-year CSM rates compared with those experiencing late BCR (19.1% vs. 4.4%; P<0.001). At multivariate analyses, time to BCR represented an independent predictor of CSM (P<0.001). CONCLUSIONS Increasing time from surgery is associated with a reduction of the risk of subsequent BCR. Additionally, time to BCR represents a predictor of CSM in these patients. These results might help provide clinicians with better follow-up strategies and more aggressive treatments for early BCR.

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Measurements of charged-particle fragmentation functions of jets produced in ultra-relativistic nuclear collisions can provide insight into the modification of parton showers in the hot, dense medium created in the collisions. ATLAS has measured jets in √sNN=2.76 TeV Pb+Pb collisions at the LHC using a data set recorded in 2011 with an integrated luminosity of 0.14 nb−1. Jets were reconstructed using the anti-kt algorithm with distance parameter values R = 0.2, 0.3, and 0.4. Distributions of charged-particle transverse momentum and longitudinal momentum fraction are reported for seven bins in collision centrality for R=0.4 jets with pjetT>100 GeV. Commensurate minimum pT values are used for the other radii. Ratios of fragment distributions in each centrality bin to those measured in the most peripheral bin are presented. These ratios show a reduction of fragment yield in central collisions relative to peripheral collisions at intermediate z values, 0.04≲z≲0.2 and an enhancement in fragment yield for z≲0.04. A smaller, less significant enhancement is observed at large z and large pT in central collisions.

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We present a precise theoretical prediction for the signal-background interference process of gg(→ h ∗) → ZZ, which is useful to constrain the Higgs boson decay width and to measure Higgs couplings to the SM particles. The approximate NNLO K-factor is in the range of 2.05 − 2.45 (1.85 − 2.25), depending on M ZZ , at the 8 (13) TeV LHC. And the soft gluon resummation can increase the approximate NNLO result by about 10% at both the 8 TeV and 13 TeV LHC. The theoretical uncertainties including the scale, uncalculated multi-loop amplitudes of the background and PDF+αs are roughly O(10%) at NNLL′. We also confirm that the approximate K-factors in the interference and the pure signal processes are the same.

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A number of indoor environmental factors, including bioaerosol or aeroallergen concentrations have been identified as exacerbators for asthma and allergenic conditions of the respiratory system. People generally spend 90% to 95% of their time indoors. Therefore, understanding the environmental factors that affect the presence of aeroallergens indoors as well as outdoors is important in determining their health impact, and in identifying potential intervention methods. This study aimed to assess the relationship between indoor airborne fungal spore concentrations and indoor surface mold levels, indoor versus outdoor airborne fungal spore concentrations and the effect of previous as well as current water intrusion. Also, the association between airborne concentration of indoor fungal spores and surface mold levels and the age of the housing structure were examined. Further, the correlation between indoor concentrations of certain species was determined as well. ^ Air and surface fungal measurements and related information were obtained from a Houston-area data set compiled from visits to homes filing insurance claims. During the sampling visit these complaint homes exhibited either visible mold or a combination of visible mold and water intrusion problems. These data were examined to assess the relationships between the independent and dependent variables using simple linear regression analysis, and independent t-tests. To examine the correlation between indoor concentrations of certain species, Spearman correlation coefficients were used. ^ There were 126 houses sampled, with spring, n=43 (34.1%), and winter, n=42 (33.3%), representing the seasons with the most samples. The summer sample illustrated the highest geometric mean concentration of fungal spores, GM=5,816.5 relative to winter, fall and spring (GM=1,743.4, GM=3,683.5 and GM=2,507.4, respectively). In all seasons, greater concentrations of fungal spores were observed during the cloudy weather conditions. ^ The results indicated no statistically significant association between outdoor total airborne fungal spore concentration and total living room airborne fungal spore concentration (β = 0.095, p = 0.491). Second, living room surface mold levels were not associated with living room airborne fungal spore concentration, (β= 0.011, p = 0.669). Third, houses with and without previous water intrusion did not differ significantly with respect to either living room (t(111) = 0.710, p = 0.528) or bedroom (t(111) =1.673, p = 0.162) airborne fungal spore concentrations. Likewise houses with and without current water intrusion did not differ significantly with respect to living room (t(109)=0.716, p = 0.476) or bedroom (t(109) = 1.035, p = 0.304) airborne fungal spore concentration. Fourth, houses with and without current water intrusion did not differ significantly with respect to living room (χ 2 (5) = 5.61, p = 0.346), or bedroom (χ 2 (5) = 1.80, p = 0.875) surface mold levels. Fifth, the age of the house structure did not predict living room (β = 0.023, p = 0.102) and bedroom (β = 0.023, p = 0.065) surface mold levels nor living room (β = 0.002, p = 0.131) and bedroom (β = 0.001, p = 0.650) fungal spore airborne concentration. Sixth, in houses with visually observed mold growth there was statistically significant differences between the mean living room concentrations and mean outdoor concentrations for Cladosporium (t (107) = 11.73, p < 0.0001), Stachybotrys (t (106)=2.288, p = 0.024, and Nigrosporia (t (102) = 2.267, p = 0.025). Finally, there was a significant correlation between several living room fungal species pairs, namely, Cladosporium and Stachybotrys (r = 0.373, p <0.01, n=65), Curvularia and Aspergillus/Penicillium (r = 0.205, p < 0.05, n= 111)), Curvularia and Stachybotrys (r = 0.205, p < 0.05, n=111), Nigrospora and Chaetomium (r = 0.254, p < 0.01, n=105) and Stachybotrys and Nigrospora (r = 0.269, p < 0.01, n=105). ^ This study has demonstrated several positive findings, i.e., significant pairwise correlations of concentrations of several fungal species in living room air, and significant differences between indoor and outdoor concentrations of three fungal species in homes with visible mold. No association was observed between indoor and outdoor fungal spore concentrations. Neither living room nor bedroom airborne spore concentrations and surface mold levels were related to the age of the house or to water intrusion, either previous or current. Therefore, these findings suggest the need for evaluating additional parameters, as well as combinations of factors such as humidity, temperature, age of structure, ventilation, and room size to better understand the determinants of airborne fungal spore concentrations and surface mold levels in homes. ^

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This study aimed to develop and validate The Cancer Family Impact Scale (CFIS), an instrument for use in studies investigating relationships among family factors and colorectal cancer (CRC) screening when family history is a risk factor. We used existing data to develop the measure from 1,285 participants (637 families) across the United States who were in the Johns Hopkins Colon Cancer Genetic Testing study. Participants were 94% white with an average age of 50.1 years, and 60% were women. None had a personal CRC history, and eighty percent had 1 FDR with CRC and 20% had more than one FDR with CRC. The study had three aims: (1) to identify the latent factors underlying the CFIS via exploratory factor analysis (EFA); (2) to confirm the findings of the EFA via confirmatory factor analysis (CFA); and (3) to assess the reliability of the scale via Cronbach's alpha. Exploratory analyses were performed on a split half of the sample, and the final model was confirmed on the other half. The EFA suggested the CFIS was an 18-item measure with 5 latent constructs: (1) NEGATIVE: negative effects of cancer on the family; (2) POSITIVE: positive effects of cancer on the family; (3) COMMUNICATE: how families communicate about cancer; (4) FLOW: how information about cancer is conveyed in families; and (5) NORM: how individuals react to family norms about cancer. CFA on the holdout sample showed the CFIS to have a reasonably good fit (Chi-square = 389.977, df = 122, RMSEA= 0.058 (.052-.065), CFI=.902, TLI=.877, GF1=.939). The overall reliability of the scale was α=0.65. The reliability of the subscales was: (1) NEGATIVE α = 0.682; (2) POSITIVE α = 0.686; (3) COMMUNICATE α = 0.723; (4) FLOW α = 0.467; and (5) NORM α = 0.732. ^ We concluded the CFIS to be a good measure with most fit levels over 0.90. The CFIS could be used to compare theoretically driven hypotheses about the pathways through which family factors could influence health behavior among unaffected individuals at risk due to family history, and also aid in the development and evaluation of cancer prevention interventions including a family component. ^

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The climate evolution of the South Shetland Islands during the last c. 2000 years is inferred from the multiproxy analyses of a long (928 cm) sediment core retrieved from Maxwell Bay off King George Island. The vertical sediment flux at the core location is controlled by summer melting processes that cause sediment-laden meltwater plumes to form. These leave a characteristic signature in the sediments of NE Maxwell Bay. We use this signature to distinguish summer and winter-dominated periods. During the Medieval Warm Period, sediments are generally finer which indicates summer-type conditions. In contrast, during the Little Ice Age (LIA) sediments are generally coarser and are indicative of winter-dominated conditions. Comparison with Northern and Southern Hemisphere, Antarctic, and global temperature reconstructions reveals that the mean grain-size curve from Maxwell Bay closely resembles the curve of the global temperature reconstruction. We show that the medieval warming occurred earlier in the Southern than in the Northern Hemisphere, which might indicate that the warming was driven by processes occurring in the south. The beginning of the LIA appears to be almost synchronous in both hemispheres. The warming after the LIA closely resembles the Northern Hemisphere record which might indicate this phase of cooling was driven by processes occurring in the north. Although the recent rapid regional warming is clearly visible, the Maxwell Bay record does not show the dominance of summer-type sediments until the 1970s. Continued warming in this area will likely affect the marine ecosystem through meltwater induced turbidity of the surface waters as well as an extension of the vegetation period due to the predicted decrease of sea ice in this area.

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El empleo de la forma normalizada de los nombres y la creación de catálogos de autoridades es un desafío permanente de los catalogadores de todas las regiones, fundamentalmente en aquellas donde el desarrollo bibliotecario y la creación de catálogos es una actividad de avance incipiente. Si bien el impulso de estas actividades tiene lugar desde la segunda mitad del siglo XX, con la evolución de las bibliografías nacionales automatizadas y la creación de entidades nacionales de control bibliográfico, es una realidad que en nuestro país –Argentina- no se disponen de tales centros y en nuestra provincia de Misiones se cuenta con muy pocos desarrollos al respecto. Así es que se pretende cooperar con la comunidad bibliotecaria de la región, creando la estructura general para catálogos de autoridades que permitan un uso uniforme de los nombres personales (y corporativos) -como puntos de acceso- para lograr una recuperación eficiente de la información. Se crearán las bases y estructuras teóricas y prácticas, sustentadas en estándares, necesarias para construir registros de autoridades de nombres personales (y corporativos) relacionados con la producción informativa local, a fin de que Bibliotecas, Editoriales e Investigadores puedan recurrir a estas fuentes para nutrirse de los aportes y productos generados.