Search results for "trend"
showing 10 items of 404 documents
Individuazione dei trend di pioggia per la Sicilia utilizzando un approccio multiscala basato sulla regressione a quantili
2021
Uno degli argomenti più attuali e controversi è se, negli ultimi decenni, le piogge intense siano diventate più frequenti come possibile effetto dei cambiamenti climatici. La centralità del tema è giustificata dalle gravi conseguenze che l’intensificarsi di questi fenomeni, in frequenza e magnitudo, potrebbe indurre a livello sociale ed economico. Basti pensare alle “flash flood”, spesso causate da eventi di precipitazione con una forte componente convettiva, che in ambito urbano mettono in crisi i sistemi di drenaggio arrecando rilevanti danni e, purtroppo, anche perdite di vite umane. La Sicilia è stata spesso monitorata con l’obiettivo di individuare delle mutazioni significative del cic…
Statistical identification with hidden Markov models of large order splitting strategies in an equity market
2010
Large trades in a financial market are usually split into smaller parts and traded incrementally over extended periods of time. We address these large trades as hidden orders. In order to identify and characterize hidden orders we fit hidden Markov models to the time series of the sign of the tick by tick inventory variation of market members of the Spanish Stock Exchange. Our methodology probabilistically detects trading sequences, which are characterized by a net majority of buy or sell transactions. We interpret these patches of sequential buying or selling transactions as proxies of the traded hidden orders. We find that the time, volume and number of transactions size distributions of …
Spatial distribution of rainfall trends in Sicily (1921–2000)
2006
Abstract The feared global climate change could have important effects on various environmental variables including rainfall in many countries around the world. Changes in precipitation regime directly affect water resources management, agriculture, hydrology and ecosystems. For this reason it is important to investigate the changes in the spatial and temporal rainfall pattern in order to improve water management strategies. In this study a non-parametric statistical method (Mann–Kendall rank correlation method) is employed in order to verify the existence of trend in annual, seasonal and monthly rainfall and the distribution of the rainfall during the year. This test is applied to about 25…
Spatial and temporal rainfall changes in the Júcar and Segura basins (1955-2016): Fine-scale trends
2018
A daily rainfall database covering the Júcar and Segura river basin authorities (east Iberian Peninsula, Spain) with high spatial density without gaps (890 series) has been created for the complete period 1955–2016. This has allowed a trend analysis of precipitation and dry/wet spells with a better spatial detail and coverage of key headwaters sectors than previous studies in this area. Results show significant negative trends for precipitation prevailing in Júcar area (an annual average loss of 51 mm), especially towards its north interior headwaters. For this last one the annual loss exceeds 200 mm (20% of precipitation). By contrast, certain pre‐littoral sectors and most of the Segura ar…
Forecasts on the development of hydrogen refuelling infrastructures in Portugal
2021
In Portugal, the transition to new forms of mobility has begun in recent years, but there are still obstacles to overcome. Currently, hybrid vehicles (PHEVs) are the most widespread and accepted by the community and that is probably due to range anxiety, having in fact the possibility of double charging (both through the thermal engine and the electric battery). Furthermore, it must be considered that in addition to electric vehicles, another valid alternative to mobility in the near future is the hydrogen vehicles one. These appear to be even more sustainable from the point of view of air emissions, but on the other hand the costs for the production of hydrogen are still too high. Then, th…
Reading, Gender, and Engagement : Lessons From Five PISA Countries
2014
The authors, members of the PISA/PIRLS Task Force, provide a summary of major gender differences in performance found overall on PISA 2009, along with relevant trends since 2000. The five countries represented by the authors are highlighted in this summary, which includes findings related to the interaction of engagement and reading literacy achievement by gender. These data are foregrounded from PISA because they add further evidence of a serious global pattern of boys’ underachievement in reading and lower reading engagement relative to girls. This is followed by a discussion of what each of our five countries has done in response to the gender gap in reading literacy. The article conclud…
Cancer incidence and mortality trends from 2003 to 2014 in Italy.
2019
Objective: To evaluate short-term (2003–2014) cancer incidence and mortality trends in Italy. Methods: Italian Cancer Registries data, available in the AIRTUM database, from 17 out of 20 regions were used. The number of incident cases and deaths were estimated for those registries and those years with incomplete information. Age-standardized rates, overall and stratified by geographic area, region, sex, cancer site, and major age group, were computed. Time trends were expressed as annual percent change of rates. Results: In Italy, among males, incidence rates for all cancers showed during 2003–2014, a significant decrease (−0.9%/year), with stronger reductions in the northwest (−1.3%/year) …
Epidemiological trends of pediatric IBD in Italy: A 10-year analysis of the Italian society of pediatric gastroenterology, hepatology and nutrition r…
2022
Introduction: The present study aimed at evaluating Italian epidemiological trends of pediatric inflammatory bowel diseases (IBD) over the period 2009–2018. Materials and methods: Data from 1969 patients enrolled in the Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition Registry, by 49 pediatric IBD centers throughout the country, were analyzed, comparing three different time intervals (2009–2012, 2013–2015, 2016–2018). Results: The number of new IBD diagnoses ranged from 175 to 219 per year, evenly distributed over the examined period of time. From 2009 to 2018, the minimal incidence ranged from 1.59 to 2.04 /105 inhabitants aged < 18 years, with an overall slight p…
Survival of 86,690 patients with thyroid cancer: A population-based study in 29 European countries from EUROCARE-5
2017
Background: Incidence rates of thyroid cancer (TC) increased in several countries during the last 30 years, while mortality rates remained unchanged, raising important questions for treatment and follow-up of TC patients. This study updates population-based estimates of relative survival (RS) after TC diagnosis in Europe by sex, country, age, period and histology.Methods: Data from 87 cancer registries in 29 countries were extracted from the EUROCARE-5 dataset. One-and 5-year RS were estimated using the cohort approach for 86,690 adult TC patients diagnosed in 2000-2007 and followed-up to 12/31/2008. RS trends in 1999-2007 and 10-year RS in 2005-2007 were estimated using the period approach…
COVID-19 pandemic, mechanical reperfusion and 30-day mortality in ST elevation myocardial infarction
2022
ObjectiveThe initial data of the International Study on Acute Coronary Syndromes - ST Elevation Myocardial Infarction COVID-19 showed in Europe a remarkable reduction in primary percutaneous coronary intervention procedures and higher in-hospital mortality during the initial phase of the pandemic as compared with the prepandemic period. The aim of the current study was to provide the final results of the registry, subsequently extended outside Europe with a larger inclusion period (up to June 2020) and longer follow-up (up to 30 days).MethodsThis is a retrospective multicentre registry in 109 high-volume primary percutaneous coronary intervention (PPCI) centres from Europe, Latin America, S…