Search results for "ELEVATION"
showing 10 items of 248 documents
Influence of surface roughness in hydrological response of semiarid catchments
2005
Abstract Here, an investigation has been carried out in order to understand the influence of the surface roughness in the definition of the hydrological response of semiarid catchments. Following a previous study of one of the authors, a modified version of TOPMODEL is used, in which the convolution routing procedure has been extended to the hillslopes by specifying the routing velocity for each pixel of the watershed. These velocities have been linked to the watershed land use through the different surface roughness whose coefficients has been derived on the basis of Engman's table. In this paper, roughness coefficient distributions are expressed as function of a unique value treated as a …
Modeling Rill Erosion at the Sparacia Experimental Area
2015
In this paper the contributions of rill and interrill components to total soil erosion monitored at event scale at the Sparacia experimental area, Southern Italy, were firstly compared and the dominance of the rill component was detected. Then, the reliability of two empirical relationships between the rill length and its eroded volume and among the morphological variables (length, width, depth and volume) describing the channelized process was tested using both direct measurements of rills, carried out for the October 3, 2011 event, and those of ephemeral gullies surveyed on February 2010 at Sparacia. The measurements of rills detected by the direct field relief were compared with those ob…
From Slope Morphometry to Morphogenetic Processes: An Integrated Approach of Field Survey, Geographic Information System Morphometric Analysis and St…
2015
Calanchi (singular: calanco) represent a typical example of badlands in the Italian peninsula, which rapidly evolve on clayey terrains such as the widespread Pliocene–Pleistocene marine clays. The present study aimed at investigating the role of the slope morphometry on the typology and distribution of morphogenetic processes in a calanchi area located in southern Italy. The research included detailed geomorphological surveying as well as morphometric and statistical analyses. The study area was first subdivided into individual hydrographic units (HUs), for which field survey allowed to identify the dominant denudation processes, their intensity and the distribution of the associated landfo…
Measuring rill erosion at plot scale by a drone-based technology
2015
The traditional direct method (i.e. metric ruler and rillmeter) of monitoring rill erosion at plot scale is time consuming and invasive because it modifies the surface of the rilled area. Measuring rill features using a drone-based technology is considered a non-invasive method allowing a fast field relief. In the experimental Sparacia area a survey by a quadricopter Microdrones md4-200 was carried out, and this relief allowed the generation of a Digital Elevation Model (DEM), with a mesh size of 1 cm and a resolution elevation equal to 2 mm, for three plots (L, G and C) affected by rill erosion. At first for the experimental L plot, which is 44 m long, the rill features were surveyed by a …
Elaboración de modelos 3D de diferentes morfologías y escalas utilizando técnicas Structure-from-Motion y fotografías terrestres
2016
En este trabajo se evalúan los métodos de foto-reconstrucción automatizada basados en el uso conjunto de las técnicas Structure from Motion (SfM) y Multi-View Stereo (MVS) para medir, monitorizar y cuantificar la dinámica de tres formas geomorfológicas: i) el glaciar rocoso del Corral del Veleta (Granada, España), ii) un paisaje de cárcavas de tipo calanchi (Sicilia, Italia) y ii) cinco pequeñas cabeceras de cárcava (Cáceres, España). Se incluyen en este trabajo los resultados sobre la precisión, utilidad y aplicabilidad de estas técnicas. Para la cuantificación de la precisión se utilizan el error cuadrático medio (RMSE) de los puntos de control que se emplean en la georreferenciación y la…
KCND3 potassium channel gene variant confers susceptibility to electrocardiographic early repolarization pattern
2019
BACKGROUND: The presence of an early repolarization pattern (ERP) on the surface ECG is associated with risk of ventricular fibrillation and sudden cardiac death. Family studies have shown that ERP is a highly heritable trait, but molecular genetic determinants are unknown. METHODS: To identify genetic susceptibility loci for ERP, we performed a GWAS and meta-analysis in 2,181 cases and 23,641 controls of European ancestry. RESULTS: We identified a genome-wide significant (P < 5 × 10(–8)) locus in the potassium voltage-gated channel subfamily D member 3 (KCND3) gene that was successfully replicated in additional 1,124 cases and 12,510 controls. A subsequent joint meta-analysis of the discov…
On versus off-hour care of patients with acute coronary syndrome and persistent ST-segment elevation in certified German chest pain units
2016
BACKGROUND Regional healthcare projects improve the off-hour care of patients with acute coronary syndromes and persistent ST-segment elevation myocardial infarction (STEMI). To analyse differences in quality of care between on and off-hour care of STEMI patients admitted to certified German chest pain units. METHODS A total of 1107 STEMI patients from the German chest pain unit registry were enrolled. Analyses comprised critical time intervals (symptoms to first medical contact (FMC), FMC to admission, symptoms to admission, symptoms to balloon, FMC to balloon, door to balloon times) and major adverse cardiac and cerebrovascular events at follow-up. RESULTS 54.8% of patients were admitted …
Multimarker risk strategy for predicting 1-month and 1-year major events in non-ST-elevation acute coronary syndromes.
2005
The aim of this study was to define the utility of the combined measurement of troponin I, myoglobin, C-reactive protein, fibrinogen, and homocysteine to predict risk in non-ST elevation acute coronary syndromes.Troponin I, myoglobin, high-sensitivity C-reactive protein, fibrinogen, and homocysteine were measured in 557 consecutive patients admitted to our institution for non-ST elevation acute coronary syndrome. The risk for major events (death or nonfatal myocardial infarction) at first month and at first year follow-up was analyzed.In a multivariate model adjusting for baseline characteristics and electrocardiographic changes, the only biomarkers related to major events at first month we…
Effect of acute heart failure following discharge in patients with non-ST-elevation acute coronary syndrome on the subsequent risk of death or acute …
2010
Little is known about how prognosis is influenced by readmission for acute heart failure (AHF) following non-ST-segment elevation acute coronary syndrome (NSTEACS). The aim of this study was to determine the prognostic effect of a first admission for AHF on the risk of acute myocardial infarction (AMI) or death in patients who survived an episode of high-risk NSTEACS.The study involved 972 consecutive patients with high-risk NSTEACS who survived after hospital admission. Readmission for AHF was selected as the main exposure variable, and its association with subsequent AMI or all-cause death was assessed using Cox proportional hazards models for time-dependent covariates that also included …
The assessment of scales of frailty and physical performance improves prediction of major adverse cardiac events in older adults with acute coronary …
2019
Abstract Background The number of older adults admitted to hospital for acute coronary syndrome (ACS) has increased worldwide. The aim of this study was to determine which scale of frailty or physical performance provides incremental improvements in risk stratification of older adults after ACS. Methods A prospective cohort of 402 older (≥70 years) ACS patients were enrolled. Data about baseline characteristics, Global Registry of Acute Coronary Events (GRACE), and Thrombolysis in Myocardial Infarction (TIMI) risk scores were collected. Before hospital discharge, seven scales of frailty and physical performance were measured. The 1-year occurrence of adverse events (cardiac death, reinfarct…