University of Lisbon

About: University of Lisbon is a education organization based out in Lisbon, Lisboa, Portugal. It is known for research contribution in the topics: Population & Context (language use). The organization has 19122 authors who have published 48503 publications receiving 1102623 citations. The organization is also known as: Universidade de Lisboa & Lisbon University.

Search for an additional, heavy Higgs boson in the H → ZZ decay channel at √s = 8 TeV in pp collision data with the ATLAS detector

Abstract: A search is presented for a high-mass Higgs boson in the , , , and decay modes using the ATLAS detector at the CERN Large Hadron Collider. The search uses proton-proton collision data at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 20.3 fb. The results of the search are interpreted in the scenario of a heavy Higgs boson with a width that is small compared with the experimental mass resolution. The Higgs boson mass range considered extends up to for all four decay modes and down to as low as 140 , depending on the decay mode. No significant excess of events over the Standard Model prediction is found. A simultaneous fit to the four decay modes yields upper limits on the production cross-section of a heavy Higgs boson times the branching ratio to boson pairs. 95 % confidence level upper limits range from 0.53 pb at GeV to 0.008 pb at GeV for the gluon-fusion production mode and from 0.31 pb at GeV to 0.009 pb at GeV for the vector-boson-fusion production mode. The results are also interpreted in the context of Type-I and Type-II two-Higgs-doublet models.

Observations of the Mediterranean outflow—I mixing in the Mediterranean outflow

Abstract: An identification of the two scores in the Mediterranean water outflow was made near the Straits of Gibraltar at about 7°W. It was estimated that the upper and lower cores constituted 95 and 72%, respectively, of the admixture with North Atlantic Central Water, whereas in proceeding around the Gulf of Cadiz towards Cape St Vincent these fractions were reduced to 50 and 38%. The most likely flow paths were determined by establishing the high coherence in the thermohaline properties associated with these cores. An interpretation of a short set of time series data, to account for the vertical periodicity that was observed in the outflow, was regarded as equally relevant to a possible explanation of a process by which the upper core might be formed within the straits.

Trends and extremes of drought indices throughout the 20th century in the Mediterranean

Abstract: . Average monthly precipitation, the original Palmer Drought Severity Index (PDSI) and a recent adaptation to Europe, the Self Calibrated PDSI (scPDSI) have been used here to analyse the spatial and temporal evolution of drought conditions in the Mediterranean during the 20th century. Monthly, seasonal and annual trends were computed for the period 1901–2000 and also for the first and second halves of this period. The statistical significance of trends was obtained with a modified version of the Mann-Kendall test that accounts for serial auto-correlation. The results show a clear trend towards drier conditions during the 20th century in most western and central Mediterranean regions, with the exceptions of northwestern Iberia and most of Turkey that reveal an increase of moisture availability. A Generalized Extreme Values (GEV) analysis was applied to the maximum and minimum regional values of scPDSI, with results pointing towards a significant decline of absolute extreme values in central areas (Italy and Balkans) and a less clear picture emerging in western (Iberia) and eastern (Turkey) realms. The inter-annual variability of the scPDSI index series is shown to be more realistic than the corresponding PDSI version, fitting better the drought episodes sequence and magnitude described in the literature for each sub-region. We assess the decadal and inter-annual variability of the scPDSI for each sub-domain and evaluate the role played by the major teleconnection patterns, and by several sea surface temperature (SST) anomalies. The main driver of scPDSI in western and central Mediterranean areas is the winter North Atlantic Oscillation (NAO) pattern that is also relevant during the following spring and summer seasons with anti-correlation values below −0.60. The second most important mode corresponds to the Scandinavian Pattern that is significantly associated to the scPDSI between winter and summer over central Mediterranean (correlation values around 0.50). Finally, the teleconnection and SST analysis has allowed us to calibrate a stepwise regression model, enabling the forecasting of summer drought conditions six months in advance. The final model obtained is capable of reproducing the observed scPDSI time series fairly well, with a correlation coefficient of 0.79 (0.77 after cross-validation) and a significant gain over climatology (SSc=59%), while the corresponding result against persistence is more modest (SSp6=11%).

Localized Nonlinear Waves in Systems with Time- and Space-Modulated Nonlinearities

Abstract: Using similarity transformations we construct explicit nontrivial solutions of nonlinear Schrodinger equations with potentials and nonlinearities depending both on time and on the spatial coordinates. We present the general theory and use it to calculate explicitly nontrivial solutions such as periodic (breathers), resonant, or quasiperiodically oscillating solitons. Some implications to the field of matter waves are also discussed.

Minimal clinically important change on the unified Parkinson's disease rating scale.

Abstract: The Unified Parkinson's Disease Rating Scale (UPDRS) is the main outcome measure in clinical trials of Parkinson's disease (PD). The minimal change that represents a clinically meaningful improvement is unknown. The objective of this study was to determine the minimal change on the UPDRS that represents a clinically meaningful improvement in early PD after 6 months of treatment. Data from two independent randomized treatment trials over 6 months involving 603 patients with de novo PD were analyzed to determine the minimal clinically important change (MCIC), referred to the status before treatment, for the UPDRS motor, activities of daily living (ADL), and total scores. An anchor-based method using ratings on a seven-point global clinical improvement was used. A change of five points on the UPDRS motor part was found to be the most appropriate cutoff score for all Hoehn and Yahr stages I to III, and a change of eight points for the UDPRS total score. For the UDPRS ADL score, an MCIC of two points for Hoehn and Yahr stages I/I.5 and II and of three points for Hoehn and Yahr stage II.5/III was the most appropriate cutoff score. These data give the first estimate for cutoffs defining clinically important changes in UPDRS ADL and motor scores. Further studies using larger databases from more diverse study populations are encouraged to better define and solidify the MCIC for the UPDRS.