63 research outputs found
Quantum Bose-Hubbard model with an evolving graph as a toy model for emergent spacetime
We present a toy model for interacting matter and geometry that explores quantum dynamics in a spin system as a precursor to a quantum theory of gravity. The model has no a priori geometric properties; instead, locality is inferred from the more fundamental notion of interaction between the matter degrees of freedom. The interaction terms are themselves quantum degrees of freedom so that the structure of interactions and hence the resulting local and causal structures are dynamical. The system is a Hubbard model where the graph of the interactions is a set of quantum evolving variables. We show entanglement between spatial and matter degrees of freedom. We study numerically the quantum system and analyze its entanglement dynamics. We analyze the asymptotic behavior of the classical model. Finally, we discuss analogues of trapped surfaces and gravitational attraction in this simple model
Spanish medical studentsâ attitudes and views towards Mental Health and Psychiatry: a multicentric cross-sectional study.
Objective The aim of this study is to investigate the attitudes
towards mental illness and psychiatry among fifth year
Spanish medical students.
Methods The study included 171 students from three medical
schools located in different areas of Spain: CĂĄdiz; UCA (n=
113), Madrid; San Pablo-CEU (n=22), and Barcelona; UAB
(n=36). They responded, prior to their undergraduate medical
course in psychiatry, to the AMI questionnaire to measure the
attitudes towards mental illness and to Balonâs adapted questionnaire
to investigate their view towards psychiatry.
Results The students (93.4 %) had a positive attitude towards
mental illness (AMI). Attitudes towards psychiatry were fairly
positive with a few negative views, specifically regarding the
role of psychiatrists (items 11 and 13) and the prestige of the
specialty (item 16). There were some statistically significant
differences between the three medical schools in the perception
of psychiatry as a medical discipline. A better attitude
towards mental illness was associated with a better view of the
overall merits of psychiatry.
Conclusions Findings suggest that Spanish medical students
do not have a negative attitude towards mental illness and they
have a good perception of psychiatry, although there are still
some misconceptions about this specialty. These studentâs
attitudes could favor an appropriate management of patients
suffering from mental illness
Health-related quality of life and long-term prognosis in chronic hypercapnic respiratory failure: a prospective survival analysis
<p>Abstract</p> <p>Background</p> <p>Health-related quality of life (HRQL) is considered as an important outcome parameter in patients with chronic diseases. This study aimed to assess the role of disease-specific HRQL for long-term survival in patients of different diagnoses with chronic hypercapnic respiratory failure (CHRF).</p> <p>Methods</p> <p>In a cohort of 231 stable patients (chronic obstructive pulmonary disease (COPD), n = 98; non-COPD (obesity-hypoventilation syndrome, restrictive disorders, neuromuscular disorders), n = 133) with CHRF and current home mechanical ventilation (HMV), HRQL was assessed by the disease-specific Severe Respiratory Insufficiency (SRI) questionnaire and its prognostic value was prospectively evaluated during a follow-up of 2â4 years, using univariate and multivariate regression analysis.</p> <p>Results</p> <p>HRQL was more impaired in COPD (mean ± SD SRI-summary score (SRI-SS) 52.5 ± 15.6) than non-COPD patients (67.6 ± 16.4; p < 0.001). Overall mortality during 28.9 ± 8.8 months of follow-up was 19.1% (31.6% in COPD, 9.8% in non-COPD). To identify the overall role of SRI, we first evaluated the total study population. SRI-SS and its subdomains (except attendance symptoms and sleep), as well as body mass index (BMI), leukocyte number and spirometric indices were associated with long-term survival (p < 0.01 each). Of these, SRI-SS, leukocytes and forced expiratory volume in 1 s (FEV<sub>1</sub>) turned out to be independent predictors (p < 0.05 each). More specifically, in non-COPD patients SRI-SS and most of its subdomains, as well as leukocyte number, were related to survival (p < 0.05), whereas in patients with COPD only BMI and lung function but not SRI were predictive.</p> <p>Conclusion</p> <p>In patients with CHRF and HMV, the disease-specific SRI was an overall predictor of long-term survival in addition to established risk factors. However, the SRI predominantly beared information regarding long-term survival in non-COPD patients, while in COPD patients objective measures of the disease state were superior. This on one hand highlights the significance of HRQL in the long-term course of patients with CHRF, on the other hand it suggests that the predictive value of HRQL depends on the underlying disease.</p
Simulating future salinity dynamics in a coastal marshland under different climate scenarios
Salinization is a wellâknown problem in agricultural areas worldwide. In the last 20â30 yr, rising salinity in the upper, unconfined aquifer has been observed in the Freepsumer Meer, a grassland near the German North Sea coast. For investigating longâterm development of salinity and water balance during 1961â2099, the oneâdimensional SoilâWaterâAtmosphereâPlant (SWAP) model was set up and calibrated for a soil column in the area. The model setup involves a deep aquifer as the source of salt through upward seepage. In the vertical salt transport equation, dispersion and advection are included. Six different regional outputs of statistical downscaling methods were used as climate scenarios. These comprise different rates of increasing surface temperature and different trends in seasonal rainfall. The simulation results exhibit opposing salinity trends for topsoil and deeper layers. Although projections of some scenarios entail decreasing salinities near the surface, most of them project a rise in subsoil salinity, with the strongest trends of up to +0.9 mg cmâ3 100 yrâ1 at â65 cm. The results suggest that topsoil salinity trends in the study area are affected by the magnitude of winter rainfall trends, whereas high subsoil salinities correspond to low winter rainfall and high summer temperature. How these projected trends affect the vegetation and thereby future land use will depend on the future management of groundwater levels in the area
Training Load and Fatigue Marker Associations with Injury and Illness: A Systematic Review of Longitudinal Studies
Test-retest reliability of entire time-series data from hip, knee and ankle kinematics and kinetics during one-leg hops for distance: Analyses using integrated pointwise indices
Motion capture systems enable in-depth interpretations of human movements based on data from three-dimensional joint angles and moments. Such analyses carry important bearings for evaluation of movement control during for instance hop landings among sports-active individuals from a performance perspective but also in rehabilitation. Recent statistical development allows analysis of entire time-series of angle and moment during hops using functional data analysis, but the reliability of such multifaceted data is not established. We used integrated pointwise indices (intra-class correlation, ICC; standard error of measurement, SEM) to establish the testâretest reliability of three-dimensional hip, knee and ankle angle and moment curves during landings of one-leg hop for distance (OLHD) in 23 asymptomatic individuals aged 18â28. We contrasted these findings to reliability of discrete variables extracted at specific events (initial contact, peak value). We extended the calculations of ICC and SEM to handle unbalanced situations (varying number of repetitions) to include all available data. Hip and knee angle curves proved reliable with stable ICC curves throughout the landing, with integrated ICCs â„ 0.71 for all planes except for knee internal/external rotation (ICC = 0.57). Hip and knee moment curves and ankle angle and moments were less reliable and less stable, particularly in the first ~ 10â25% of the landing (integrated ICCs 0.44â0.57). Curve data were generally not in agreement with the results for discrete event data, thus advocating analysis of curve data which contains more information. To conclude, hip and knee angle curve data during OLHD landings can reliably be evaluated, while moment curves necessitate careful consideration
Evaluation of various spatial rainfall datasets for streamflow simulation using SWAT model of Wunna basin, India
mizuRoute version 1: a river network routing tool for a continental domain water resources applications
This paper describes the first version of a stand-alone runoff routing tool,
mizuRoute. The mizuRoute tool post-processes runoff outputs from any
distributed hydrologic model or land surface model to produce spatially
distributed streamflow at various spatial scales from headwater basins to
continental-wide river systems. The tool can utilize both traditional
grid-based river network and vector-based river network data. Both types of
river network include river segment lines and the associated drainage basin
polygons, but the vector-based river network can represent finer-scale river
lines than the grid-based network. Streamflow estimates at any desired
location in the river network can be easily extracted from the output of
mizuRoute. The routing process is simulated as two separate steps. First,
hillslope routing is performed with a gamma-distribution-based
unit-hydrograph to transport runoff from a hillslope to a catchment outlet.
The second step is river channel routing, which is performed with one of two
routing scheme options: (1)Â a kinematic wave tracking (KWT) routing
procedure; and (2)Â an impulse response function â unit-hydrograph (IRF-UH)
routing procedure. The mizuRoute tool also includes scripts (python, NetCDF
operators) to pre-process spatial river network data. This paper
demonstrates mizuRoute's capabilities to produce spatially distributed
streamflow simulations based on river networks from the United States
Geological Survey (USGS) Geospatial Fabric (GF) data set in which over 54âŻ000
river segments and their contributing areas are mapped across the contiguous
United States (CONUS). A brief analysis of model parameter sensitivity is
also provided. The mizuRoute tool can assist model-based water resources
assessments including studies of the impacts of climate change on
streamflow
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