Faglie e terremoti all’Etna: analisi delle ricorrenze degli eventi sismici e confronto fra ipotesi stazionarie e time-dependent per la stima della pericolosità sismica

I modelli di pericolosità sismica tradizionali utilizzano ipotesi semplificate di distribuzione omogenea della sismicità nello spazio, e stazionaria nel tempo. Negli ultimi decenni, grazie anche ad una aumentata disponibilità di osservazioni geologiche e paleosismologiche, stanno prendendo rilievo modelli più strettamente collegati alla fagliazione sismogenetica, che tengano in considerazione anche le variazioni temporali legate al ciclo sismico. In Italia, queste applicazioni sono prevalentemente a carattere metodologico ed esplorativo, dato che solo un limitatissimo numero di strutture sismogenetiche dispone di dati osservativi indispensabili per questo tipo di analisi (ad es. Pace et al., 2006; Peruzza, 2006; Peruzza et al., 2008). Tra queste, le faglie etnee rappresentano un caso di studio particolare per entità, tipologia e frequenza della fagliazione superficiale e della sismicità associata (Azzaro, 1999). Per tale motivo, nell’ambito del progetto DPC V4-Flank finalizzato alla valutazione dell’hazard connesso alla dinamica di fianco all’Etna, abbiamo applicato ai principali sistemi di faglie attive dell’edificio vulcanico, le tecniche di stima dell’hazard basate sulle ipotesi di terremoto caratteristico e dipendenza temporale dall’ultimo evento. A partire dal modello sismotettonico (Azzaro, 2004) e dal catalogo sismico di riferimento (CMTE, Azzaro et al., 2000, 2002, 2006), sono state analizzate le sequenze di eventi sismici attribuibili alle diverse strutture sismogenetiche e ricostruite le loro storie sismiche. Una caratteristica comune nello stile di rilascio sismico di molte faglie è la presenza di terremoti maggiori e minori alternati nel tempo, in una sorta di cicli sismici intervallati da brevi periodo di ritorno (decine di anni) (Fig. 1 in alto). E’ evidente, per alcune strutture sismogenetiche contigue, anche la loro attivazione alternata nel tempo (Fig. 1 in basso). Per ogni singola faglia sono stati quindi verificati i possibili modelli di occorrenza applicando distribuzioni diverse in accordo con ipotesi stazionarie o time-dependent (Fig. 2). I risultati preliminari suggeriscono una certa periodicità degli eventi maggiori associati alle diverse strutture, rappresentata dal coefficiente di variazione sul dataset degli intertempi. Dal momento che le stime di hazard sismico variano in relazione al diverso tempo trascorso dall’ultimo terremoto su ciascuna struttura, applicando un processo con memoria attraverso una funzione di distribuzione del tipo BPT, è stato calcolato l’incremento o la diminuzione della probabilità di un successivo evento sismico, rispetto alle ipotesi poissoniane. Gli sviluppi previsti sono mirati a comprendere anche il ruolo delle strutture sismogenetiche analizzate nei processi geodinamici locali

Stressed caregivers. An observational study in a rehabilitation care home in western Sicily

Introduction: Caregiver is the person who takes care of the patient from the practical point of view, helping him in managing the disease and carrying out daily activities, but also supporting him on an emotional level. Caregiver burnout is a state of physical, emotional, and mental exhaustion that may be accompanied by a change in attitude from positive and caring to negative and unconcerned. The aim of the study was to understand what factors were associated with having panic attacks or crying crises in the caregivers of our study population. Materials and methods: The study design is observational. An anonymous questionnaire was administered to caregivers of the patients of a hospital for the intensive post-acute rehabilitation from April 2016 to December 2018. The statistical significance level chosen for the entire analysis was 0.05. The covariates to be included were selected using a stepwise backward selection process, with a univariate p-value <0.25 as the main criterion. Results are expressed as adjusted Odds Ratio (aOR) with 95% Confidence Intervals (CI). Results: The sample consists of 302 caregivers (60.93% was females and 39.07% was males). The mean age of the sample is 53.42 years old (SD ± 12.19). The multivariable logistic regression model shows that the risk to have panic or crying crisis is significantly associated with the following indipendent variables: female gender (aOR 27.06); living with the patient (aOR 4.38); had claimed that the problems related to the illness of their family member is a source of stress (aOR 23.54), smoking cigarettes (aOR 14.68); had claimed that taking care of their client affected their personal financial statement/career (aOR 5.95), having free time (aOR 7.68). Conclusions: In our study we found a greater probability of having panic attacks or crying crises in female subjects, smokers, who think they have sacrificed their careers to take care of the person they follow from a welfare point of view. Certainly in the light of what has emerged it is necessary to dedicate and pay close attention to the psychological and social aspects of the caregiver

When probabilistic seismic hazard climbs volcanoes: the Mt. Etna case, Italy – Part 2: Computational implementation and first results

Abstract. This paper describes the model implementation and presents results of a probabilistic seismic hazard assessment (PSHA) for the Mt. Etna volcanic region in Sicily, Italy, considering local volcano-tectonic earthquakes. Working in a volcanic region presents new challenges not typically faced in standard PSHA, which are broadly due to the nature of the local volcano-tectonic earthquakes, the cone shape of the volcano and the attenuation properties of seismic waves in the volcanic region. These have been accounted for through the development of a seismic source model that integrates data from different disciplines (historical and instrumental earthquake datasets, tectonic data, etc.; presented in Part 1, by Azzaro et al., 2017) and through the development and software implementation of original tools for the computation, such as a new ground-motion prediction equation and magnitude–scaling relationship specifically derived for this volcanic area, and the capability to account for the surficial topography in the hazard calculation, which influences source-to-site distances. Hazard calculations have been carried out after updating the most recent releases of two widely used PSHA software packages (CRISIS, as in Ordaz et al., 2013; the OpenQuake engine, as in Pagani et al., 2014). Results are computed for short- to mid-term exposure times (10 % probability of exceedance in 5 and 30 years, Poisson and time dependent) and spectral amplitudes of engineering interest. A preliminary exploration of the impact of site-specific response is also presented for the densely inhabited Etna's eastern flank, and the change in expected ground motion is finally commented on. These results do not account for M  >  6 regional seismogenic sources which control the hazard at long return periods. However, by focusing on the impact of M  <  6 local volcano-tectonic earthquakes, which dominate the hazard at the short- to mid-term exposure times considered in this study, we present a different viewpoint that, in our opinion, is relevant for retrofitting the existing buildings and for driving impending interventions of risk reduction

Chronic obstructive pulmonary disease (COPD) in elderly subjects: impact on functional status and quality of life

AbstractChronic obstructive pulmonary disease (COPD) is an important cause of morbidity and disability. Many studies have investigated factors influencing quality of life (QoL) in middle-aged COPD sufferers, but little attention has been given to elderly COPD. The aim of the present study was to investigate the impact of COPD on QoL and functional status in the elderly. Sixty COPD patients and 58 healthy controls over 65 years old were administered Pulmonary Function Tests, 6min Walking Test (6MWD) for exercise tolerance, the Barthel Index and Mini Mental State Examination (MMSE) for functional status, the Geriatric Depression Scale (GDS) for mood, and the Saint George Respiratory Questionnaire (SGRQ) for QoL. FEV1 and P aO2 were reduced in COPD patients. Also the distance walked during 6MWD was significantly shorter for patients than controls (282.5±89.5 vs. 332.9±95.2m; P<0.01). Moreover, COPD patients had significantly worse outcomes for the Barthel Index, GDS and SGRQ. The logistic regression model demonstrated that a decrease in FEV1 is the factor most strictly related to the deterioration of QoL in COPD patients. Mood was also an independent factor influencing QoL. In conclusion, elderly COPD patients show a substantial impairment in QoL depending on the severity of airway obstruction; symptoms related to the disease may be exaggerated by mood deflection

The health impact of remarriage behavior on chronic obstructive pulmonary disease: findings from the US longitudinal survey

<p>Abstract</p> <p>Background</p> <p>Chronic obstructive pulmonary disease (COPD) is a major disease among adults, and its deterioration was reported to be associated with psychological imbalance. Meanwhile, bereavement and divorce have proven harmful to the health status of a surviving spouse. But few studies have been conducted to evaluate the remedial effect on survivors' health outcome by remarriage after bereavement. The present study thus examined the associations between remarriage and the onset of COPD.</p> <p>Methods</p> <p>Our cohort was drawn from Health and Retirement Study participants in the United States, and consisted of 2676 subjects who were divorced or bereaved from 1992 to 2002. We then followed them for up to 11 years and assessed the incidence rate of COPD using a Cox proportional hazard model after adjusting for marital status, age, gender, education and the number of cigarettes smoked.</p> <p>Results</p> <p>Among all subjects, 224 who remarried after bereavement or divorce tended to be younger and more male dominated. Remarriage after bereavement/divorce was associated with significantly decreased risk of COPD onset for overall subjects [hazard ratio (HR): 0.51, 95% confidence interval (95% CI): 0.28-0.94], female subjects [HR: 0.36, 95% CI: 0.13-0.98], and for those under 70 years old [HR: 0.36, 95% CI: 0.17-0.79].</p> <p>Conclusion</p> <p>This study investigates the impact of remarriage on health outcome based on a large-scale population survey and indicates that remarriage significantly correlates with reduced risk of COPD incidence, even after adjusting smoking habit.</p

Earthquake rupture forecasts for the mps19 seismic hazard model of Italy

In recent years, new approaches for developing earthquake rupture forecasts (ERFs) have been proposed to be used as an input for probabilistic seismic hazard assessment (PSHA). Zone-based approaches with seismicity rates derived from earthquake catalogs are commonly used in many countries as the standard for national seismic hazard models. In Italy, a single zone-based ERF is currently the basis for the official seismic hazard model. In this contribution, we present eleven new ERFs, including five zone-based, two smoothed seismicity-based, two fault-based, and two geodetic-based, used for a new PSH model in Italy. The ERFs were tested against observed seismicity and were subject to an elicitation procedure by a panel of PSHA experts to verify the scientific robustness and consistency of the forecasts with respect to the observations. Tests and elicitation were finalized to weight the ERFs. The results show a good response to the new inputs to observed seismicity in the last few centuries. The entire approach was a first attempt to build a community-based set of ERFs for an Italian PSHA model. The project involved a large number of seismic hazard practitioners, with their knowledge and experience, and the development of different models to capture and explore a large range of epistemic uncertainties in building ERFs, and represents an important step forward for the new national seismic hazard model