Assessing the influence of around-source deep crustal heterogeneities on the seismic wave propagation by 3-D broad-band numerical modelling

Tectonic and seismic activities induce crustal rock fracturing in the immediate surroundings of buried fault discontinuities. The heterogeneous nature of this 3-D scatter distribution leaves a high-frequency footprint on the recorded wave-field at surface. This study represents an attempt to clarify the complex relationship between the propagated wave-field and the statistical properties of the regional medium. This objective is pursued by inspecting the broadband (0-25Hz) synthetic wave-forms obtained by sourceto-site 3-D numerical simulations in regional-size scenarios. The presented numerical study compares the major differences obtained when including heterogeneous properties in the model. Coda-waves are analysed and the high-frequency attenuation is assessed by computing the k coefficient for different source-station configurations.This work was performed using HPC resources from the Mésocentre computing center of CentraleSupélec and École Normale Supérieure Paris-Saclay (http://mesocentre.centralesupelec.fr/)

Systematic review: Effective Home Support in Dementia Care, components and impacts – Stage 2, effectiveness of home support interventions.

Aim: To explicate the outcomes of home support interventions for older people with dementia and/or their carers to inform clinical practice, policy and research. Background: Most people with dementia receive support at home. However, components and effectiveness of home support interventions have been little explored. Design: Systematic review with narrative summary. Data sources: Electronic searches of published studies in English using PubMed, Cochrane Central Register of Controlled Trials, PsychINFO, CINAHL, Applied Social Science Index and CSA Social Services Abstracts. Databases and sources were searched from inception to April 2014 with no date restrictions to locate studies. Review methods: The PRISMA statement was followed and established systematic review methods used. Using 14 components of care for people with dementia and their carers, identified previously, data across studies were synthesized. Interventions were grouped and described and effectiveness ratings applied. Qualitative studies were synthesized using key themes. Results: Seventy studies (four qualitative) were included. Most were directed to carers and of high quality. Seven interventions for carers and two for people with dementia were identified, covering 81% of studies. Those relating to daily living, cognitive training and physical activity for people with dementia were absent. Measures of effectiveness were influenced mainly by the intensity (duration and frequency) of interventions. Those containing education, social support and behaviour management appeared most effective. Conclusion: These interventions reflect emergent patterns of home support. Research is required to identify effective interventions linked to the stage of dementia, which can be applied as part of routine clinical care

Health care providers' perceptions of the vulnerability of persons with disabilities: Sociological frameworks and empirical analyses

In this study, we explored health care providers' perceptions about their professional responsibility for persons with disabilities. We examined the providers' perceptions of the vulnerability of persons with disabilities to sexual exploitation. We also elicited the professionals' assumptions about the consequences of such exploitation to the persons with disability and the professionals working with them. Our analyses indicated that these professionals perceived that different categories of disability pose different risk of sexual exploitation. Populations with forms of cognitive impairment were considered most vulnerable. In terms of professional responsibility for the care of persons who might have experienced sexual exploitation, respondents reported least confidence in their ability to detect instances of exploitation. In contrast, respondents expressed greater confidence in their ability to report and conduct follow-up of abuse. The professionals anticipated providing emotional support to persons who experienced exploitation. We discuss the study's implications for training and policy formation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45566/1/11195_2005_Article_BF01102394.pd

Risk factors for disability among U.S. adults with arthritis

This article studies risk factors for physical and social disability among U.S. adults ages 55+ who have arthritis, compared to non-arthritis persons of those ages. The dependent variables refer to difficulties in walking, physical functioning (motions and strength), personal care, and household care. The data set is the Supplement on Aging (SOA) (n = 16,148) that accompanied the 1984 National Health Interview Survey. The SOA data are cross-sectional; relationships of risk factors to disability suggest causation but do not directly demonstrate it. Logistic regressions show that risk factors are similar for arthritis and non-arthritis people, with one important exception. (1) The similarities are: For both groups, odds of disability rise with age, diminish with education, and are higher for non-whites and non-married persons. Disability rises with number of chronic diseases and impairments, and it is elevated for underweight persons (Body Mass Index (BMI) < 20; further analysis indicates this reflects incomplete control of their severe illness status). Long duration of arthritis and recent medical care for it are associated with disability. (2) The exception is: Severe overweight (BMI [ges] 30) is a disability risk factor for arthritis people, but not for non-arthritis people. Previous research has shown that obesity/overweight is a risk factor for etiology of osteoarthritis; our analysis now shows its continued importance for disability when the disease is present.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29565/1/0000653.pd

Influence des hétérogénéités de la lithosphère et des structures complexes des failles sur le contenu fréquentiel des ondes sismiques

Earthquakes, till today, have disastrous losses and damages. In order to measure the seismic risk and to improve the seismic design; it is important to take into account the heterogeneity of the propagating medium to identify its impact on the seismic wave field during the propagation.In this work, we were mainly focused on the heterogeneities of the crust and the complex structures close to the seismic fault. The modeling of these heterogeneities allowed us to determine their effects on the frequency content of the seismic wave captured at the free surface. The heterogeneous medium is modeled by randomly fluctuating properties.First of all, the elasto-dynamic equations are developed considering a weakly heterogeneous regime. This regime corresponds to the case where the characteristic length of the fluctuations is of the order of the studied wavelength with a low variance and a propagation distance much greater compared to the length of the fluctuations. A plane wave propagating through a horizontally stratified random layer at normal incidence was first considered. In this case the P-SV-SH waves are not coupled, and it was possible to determine an attenuation of a frequency part of the wave propagating through the random medium. This attenuation corresponds to an energy that is not transported all the way to the other side of the random slab.Then, an inclined incident wave with a small inclination was considered. In this case, there is a strong coupling between the P wave and the SV wave. Considering a limited development of the wave’s inclination, it is possible to the write the stochastic differential equations for a small inclination where the coupling terms appear. The implementation of numerical simulations allowed to highlight the difference in attenuation with the case of normal incidence and also to show in a qualitative way the couplings and energy transfers between P and SV for the inclined wave.Through numerical simulations, we have studied the effects of small amplitude heterogeneities over large distances, which are more representative of the heterogeneities of the lithosphere. By considering both intra- and inter-seismic events, we show the effect of heterogeneities on characteristic quantities such as PGA. In addition, we have reproduced the approach for the computation of the empirical parameter kappa. This parameter, used in earthquake engineering, models the high frequency attenuation. From the calculation of kappa via the numerical simulations performed, a direct link between the theoretical attenuation obtained in this work and this empirical model was made.In the last part, we observed preliminary results on the consideration of the highly fractured areas at the vicinity of the fault. In this case we were able to illustrate that part of the energy loses its coherency and a localization of part of the frequencies as well as a possible "trapping" effect of the energy within the heterogeneous structure.Les tremblements de terre ont encore aujourd’hui des conséquences dramatiques. Pour permettre de mesurer le risque sismique et pour parfaire le dimensionnement parasismique ; il est important de prendre en compte le caractère hétérogène du milieu de propagation pour en déterminer l’impact sur le champ d’onde au cours de la propagation.Nous nous sommes essentiellement intéressés dans le cadre de ce travail aux hétérogénéités de la croûte et aux structures complexes proches des failles sismiques. La modélisation de ces hétérogénéités a permis de déterminer leurs effets sur le contenu fréquentiel de l’onde transmise captée en surface. Nous avons choisi d’approximer les fluctuations des propriétés du milieu par un milieu aléatoire.Nous avons tout d’abord développé les équations de l’élasto-dynamique dans le cas où nous nous sommes placés dans un régime faiblement hétérogène. Ce régime correspond au cas où la longueur caractéristique des fluctuations est de l’ordre de la longueur d’onde étudiée avec une variance faible et une distance de propagation très grande devant la longueur des fluctuations. Il a tout d’abord été considéré l’arrivée d’une onde plane en incidence normale sur une couche aléatoire stratifiée horizontalement. Dans ce cas, les ondes P-SV-SH sont découplées et il a été possible de déterminer une atténuation d’une partie fréquentielle de l’onde traversant le milieu aléatoire. Cette atténuation correspond à une partie manquant de l’énergie injectée sur une bande de fréquence donnée.Nous avons ensuite considéré un cas où l’onde incidence est une onde plane inclinée d’inclinaison faible. Il y a, dans ce cas, un couplage fort entre l’onde P et l’onde SV. A partir d’un développement limité sur l’inclinaison de l’onde, il est possible d’arriver à l’écriture du système d’équations différentielles stochastiques où l’on verra apparaitre les termes de couplages. La mise en place des simulations numériques nous a permis de mettre en avant la différence d’atténuation avec le cas de l’incidence normale et également de montrer de manière qualitative les couplages et les transmissions d’énergie entre P et SV.Nous avons étudié à travers des simulations numériques, les effets d’hétérogénéités d’amplitudes faibles sur des grandes distances, plus représentatives des hétérogénéités de la lithosphère. En se plaçant à la fois dans le cas d’événements intra-sismiques et inter-sismiques, on montre l’effet des hétérogénéités sur des grandeurs caractéristiques tel que les PGA. De plus, nous avons reproduit la démarche pour le calcul du paramètre empirique kappa. Ce paramètre, utilisé en génie parasismique, modélise l’atténuation haute fréquence. A partir du calcul de kappa via les simulations numériques effectuées, un lien direct entre l’atténuation théorique obtenue dans ces travaux et ce modèle empirique a été fait.Dans une dernière partie, nous avons observé des résultats préliminaires sur la prise en compte des zones très fracturées au niveau de la faille. Dans ce cas nous avons pu illustrer que nous avons création d’une onde incohérente, et une localisation d’une partie des fréquences ainsi qu’un possible effet de « piégeage » de l’énergie au sein de la structure hétérogène

Questions et discussions

Colvez Ch. Questions et discussions. In: La revue pédagogique, tome 79, Juillet-Décembre 1921. pp. 34-36

Un point de vue sur l’avenir des indicateurs d'espérance de vie en santé

Cet article exprime un point de vue personnel sur l'avenir des indicateurs d'espérance de vie en santé (EVS) en se plaçant du point de vue de la pratique de santé publique. La reflexion est centrée sur les modalités envisageables pour opérer le transfert des connaissances et des procédures du milieu de la recherche vers le milieu de la statistique sanitaire afin que les EVS deviennent des indicateurs de routine de I'état de sante de la population. Selon le point de vue exprimé, la diffusion des EVS passe dans un premier temps par le concept plus limité d'espérance de vie sans incapacité. Les reflexions portent sur la sélection des aspects d'incapacité, la standardisation des instruments, le type d'enquête à envisager, le rôle des grands instituts de statistique pour I'inlroduction d'un calcul de routine. Enfin les themes des recherches qui pourraient être engagées pour faciliter la diffusion des EVS dans la pratique sont très brièvement abordés.The article expresses the author's point of view on the future of indicators of health expectancy from the standpoint of the public health practitioner. The discussion focuses on the possible ways to transfer knowledge and procedures from the research community to the health statistics field so that health expectancy can be used as a routine indicator of the health status of a population. According to the author, the concept of health expectancy must first be seen through the more limited concept of disability free life expectancy. The article looks at the selection of aspects of disability standardization of instruments, types of surveys, the role of major statistics organisations in introducing routine calculation. The last section looks briefly at possible research avenues to transfer the concept of health expectancy to the practical level.Este articula expresa un punto de vista personal acerca del futuro de los indicadores de esperanya de vida en estado saludable (EVSi pues se coloca desde el punto de vista de la practica de la salud publica. Se centra esta reflexion sobre los distintos modos posibles de transferir los conocimientos y proccdimientos del ambito de la investiqacion al de la estadistica sanitaria para que las esperanzas de vida en estado saludable se vuelvan indicadores de rutma del estado de salud de la poblacion. Segun el punto de vista que se expresa aqui, la esperanza de vida en estado saludable debe posar antes que nada por el concepto mas limitado de esperanza de vida sui incapacidad. Las reflexiones se refieren tanto a a la seleccion de los tipos de incapacidad corno la tiptficacion de los instrumentas, el tipo de encuesta a considerar, el papel de los grandes institutos de estadistica para la insercion de un calculo de rutina. Se abordan muy brevemente en la ultima parte los temas de las investigaciones que podnan lanzarse para ayudar a difundu de manera practica las esperanzas de vida en estado saludable