Search results for "persist"
showing 10 items of 427 documents
Evaluation of different InSAR multi-baseline construction methods over a dam in southern Italy
2018
Monitoring dam displacements using different techniques allows an evaluation of their structural behaviour over time. In this study, dam displacements (for the Castello dam, Agrigento, Italy) have been investigated using different Interferometric Synthetic Aperture Radar (InSAR) techniques exploiting a freely available dataset from the EU Copernicus Sentinel-1 SAR built by the European Space Agency (ESA). The dataset includes Sentinel 1A (S1A) images acquired in dual-polarization and Interferometric Wide (IW) swath using the Terrain Observation with Progressive Scans SAR (TOPSAR) mode. Three main Multi-Baseline Construction methods based on the identification of Persistent Scatterers (PS) h…
Organochlorinated pesticides in sediments from the Lake Albufera of Valencia (Spain).
2005
Bottom sediment samples from 121 sites of the Lake Albufera of Valencia were analyzed. Dieldrin, endrin, heptachlor and op'-DDT were not detected (0.01 ng g(-1)) in 88-93% of the sites. Aldrin and HCB concentration ranges were between0.01 and 0.1 ng g(-1) in 86% and 94% of the sites, respectively. Heptachlor-epoxide and lindane 95% confidence intervals were 0.2-0.5 and 0.06-0.12, respectively. The greatest average concentration corresponds to pp'-DDE, pp'-DDD and pp'-DDT. The sum of six isomers and derivatives of the DDT average concentration reaches 2.1 ng g(-1), as opposed to 2.7 ng g(-1) for the sum of 13 pesticides considered. In the site with a major contamination, 27.0 ng g(-1) of pp'…
Intracerebral Borna Disease Virus Infection of Bank Voles Leading to Peripheral Spread and Reverse Transcription of Viral RNA
2011
Bornaviruses, which chronically infect many species, can cause severe neurological diseases in some animal species; their association with human neuropsychiatric disorders is, however, debatable. The epidemiology of Borna disease virus (BDV), as for other members of the family Bornaviridae, is largely unknown, although evidence exists for a reservoir in small mammals, for example bank voles (Myodes glareolus). In addition to the current exogenous infections and despite the fact that bornaviruses have an RNA genome, bornavirus sequences integrated into the genomes of several vertebrates millions of years ago. Our hypothesis is that the bank vole, a common wild rodent species in traditional B…
Application of the Wood model to lactation curves of Comisana sheep
1997
Abstract Ninety-two ewes of the Comisana breed were used in a study to verify the forecasting capacity of the mathematical model proposed by Wood for fitting sheep data, and to evaluate the effect of the environmental factors affecting the parameters of the lactation curve. The Wood model underestimated the total lactation milk production with an error margin of 12.2 ± 7.8 kg of milk corresponding to 10.9 ± 6.6%. There was a strong influence of order of lambing × lambing season interaction on the lactation parameters. The curves for the winter lambing ewes demonstrated a higher peak production than autumn lambing ewes (1728.4 vs. 1082.6 g, P ≤ 0.05 for the second lambing ewes and 1772.8 vs.…
HABILIDADES MATEMÁTICAS INICIALES Y DIFICULTADES MATEMÁTICAS PERSISTENTES
2017
Abstract.INITIAL MATH SKILLS AND PERSISTENT MATH DIFFICULTIESThe aim of the present study was to analyse the differences in certain basic mathematical competences (for example, counting, logical operations, magnitude comparability skills) assessed in. Early Childhood Education between children with persistent difficulties in the area of mathematics in 2nd Primary Education and children with adequate performance. The final sample of the study consisted of 180 children (composed initially of 209 pre-schoolers), of which 6.6% showed persistent mathematics difficulties (n = 12) and 45.5% presented an adequate performance in both measurements (n = 82). In Early Childhood Education we administere…
On the Asymmetric Recognition of Good and Bad News in France, Germany and the United Kingdom
2001
We investigate whether accounting systems recognise bad news more promptly in earnings than good news, where news is proxied by changes in share price. The analysis is based on a sample of firm/years drawn from France, Germany, and the UK during 1990 to 1998. These three countries are the originators of three distinct legal traditions. Previous studies have argued that asymmetric recognition, one manifestation of conservative accounting, is sensitive to legal background and history. We find that in all three countries the contemporaneous association between earnings and returns is much stronger for bad news (i.e. when price changes are negative) than for good news, and although the results …
Fiscal Policy Responsiveness, Persistence and Discretion
2008
This paper analyzes the different characteristics of fiscal policy using a two-step estimation procedure. First, we decompose both government spending and government revenue into three components: responsiveness, persistence and discretion. Second, we assess the determinants of these characteristics. Using data from 132 countries, our results show that fiscal policy is more persistent than responsive to economic conditions, which implies that the authorities may have less leeway in the short-run notably to curb spending behavior. In addition, countries characterized by greater fiscal persistence have less discretion and responsiveness. Finally, macroeconomic, institutional and geographic va…
One swallow does not make a summer: episodes and persistence in high growth
2021
This paper analyzes firms’ episodes (spells) of high growth (HG) using a sample of Spanish manufacturing firms observed over two decades. The use of duration models allows us to investigate the following: (i) the probability of experiencing HG episodes, (ii) persistence in HG, and (iii) the determinants of the transitions in and out of the HG state and whether their impact varies over the business cycle. We find that about half of the firms experience at least one HG episode, but they seldom experience more than one. Moreover, high-growth status is rarely repeated due to high first-year selection. Yet, in subsequent years beyond the first one, the hazard rate from HG status falls substantia…
Nonlinear GARCH models for highly persistent volatility
2005
In this paper we study new nonlinear GARCH models mainly designed for time series with highly persistent volatility. For such series, conventional GARCH models have often proved unsatisfactory because they tend to exaggerate volatility persistence and exhibit poor forecasting ability. Our main emphasis is on models that are similar to previously introduced smooth transition GARCH models except for the novel feature that a lagged value of conditional variance is used as the transition variable. This choice of the transition variable corresponds to the idea that high persistence in conditional variance is related to relatively infrequent changes in regime. U sing the theory of Markov chains w…
Cross-country variation in patience, persistent current account imbalances and the external wealth of nations
2022
This paper is the first to utilize large-scale international surveys on economic preferences to examine the long-run relationships between patience, current accounts and external wealth. We find robust empirical evidence that countries with more patient individuals tend to run persistent current account surpluses, which in turn result in the accumulation of foreign assets. This theoretically plausible but empirically unexplored relationship holds true for euro area current account imbalances, global current account imbalances and net foreign asset positions worldwide. While the existing current account literature concentrates on proximate macroeconomic determinants, this paper’s extension o…