Analisi multi-diagnostica dello stato di evoluzione dinamica dell'ammasso globulare M15

Questo lavoro di tesi si inserisce nel contesto dello studio dell'evoluzione dinamica degli ammassi globulari. Essi sono dei sistemi collisionali, in cui le interazioni gravitazionali tra le stelle comportano continui scambi di energia cinetica tra le componenti di diversa massa. All'interno di questi ambienti molto densi, le frequenti interazioni possono arrivare a modificare profondamente le proprietà strutturali dell'ammasso. Infatti, sebbene gli ammassi globulari della Via Lattea abbiano tutti un’età cronologica molto simile, essi si sono evoluti dal punto di vista dinamico in maniera diversa l’uno dall’altro, in base alle loro dinamica interna, oltre che alle diverse interazioni con la Galassia. Pertanto, gli ammassi globulari rappresentano il laboratorio ideale per studiare i fenomeni di dinamica stellare. Questo lavoro di tesi consiste in uno studio dello stato di evoluzione dinamica dell'ammasso globulare M15, uno dei sistemi più massicci e densi presenti nella Via Lattea. Tale studio è stato effettuato mediante l’utilizzo di tre differenti indicatori di evoluzione dinamica: la distribuzione radiale delle Blue Straggler Stars, la variazione radiale della funzione di massa e la distribuzione radiale della frazione di stelle binarie. Per questo scopo, ci siamo serviti di una combinazione di dati ottenuti con Hubble Space Telescope e telescopi da terra della classe degli 8 m, ottimizzata al fine di campionare l'ammasso in tutta la sua estensione radiale. I risultati ottenuti hanno permesso di classificare, utilizzando questi tre diversi indicatori indipendenti, l’ammasso globulare M15 come un sistema dinamicamente molto evoluto. Prima di questa tesi, l'unico indizio in questo senso era rappresentato dalla forma del profilo di brillanza superficiale, che mostra la deviazione centrale dal modello di King attesa nel caso di un sistema che ha già subito il collasso del nucleo

Galactic chemical evolution of Lithium: interplay between stellar sources"

In this paper we study the evolution of 7Li in the Galaxy considering the contributions of various stellar sources: type II supernovae, novae, red giant stars, and asymptotic giant branch (AGB) stars. We present new results for the production of 7Li in AGB stars via the hot bottom burning process, based on stellar evolutionary models by Frost (1997). In the light of recent observations of dense circumstellar shells around evolved stars in the Galaxy and in the Magellanic Clouds, we also consider the impact of a very high mass-loss rate episode (superwind) before the evolution off the AGB phase on the 7Li enrichment in the interstellar medium. We compare the Galactic evolution of 7Li obtained with these new 7Li yields (complemented with a critical re-analysis of the role of supernovae, novae and giant stars) with a selected compilation of spectroscopic observations including halo and disk field stars as well as young stellar clusters. We conclude that even allowing for the large uncertainties in the theoretical calculation of mass-loss rates at the end of the AGB phase, the superwind phase has a significant effect on the 7Li enrichment of the Galaxy.Comment: Accepted for ApJ, 40 pages, 9 figure

Support for experiments at INFN-T1

The Italian WLCG Tier-1 located in Bologna and managed by INFN-CNAF has a long tradition in supporting several research communities in the fields of High-Energy Physics, Astroparticle Physics, Gravitational Waves, Nuclear Physics and others, to which provides computing resources in the form of batch computing, both HPC, HTC and Cloud, and storage. Although the LHC experiments at CERN represent the main users of the Tier-1 resources, an increasing number of communities and experiments are also being supported in all of their computing activities. Due to this demanding user base, an efficient support system is needed in order to assure a smooth and appropriate exploitation of the computing infrastructure. In this framework, such a role is played by the Tier-1 User Support group, which acts as the entry point for services, support requests, and problem reports. The group makes use of multiple systems to meet the different needs and specificities of the supported experiments. Moreover, the group continuously maintains detailed knowledge base in the form of an on-line user guide and develops tools to advertise specific information about the services available to the communities in a form that is easy to access and use. The communication channels are represented by ticketing systems and also by mailing lists used for a more direct communication, allowing to promptly notify maintenance interventions, downtimes and more in general all the new features and services provided by the center. In this paper, the ticketing systems, tools, platforms and services that User Support offers, and the internal organization of the department will be described. Future workflow plans in view of the DATACLOUD project, which will require an increasing effort, will also be presented

Circulating CRP Levels Are Associated with Epicardial and Visceral Fat Depots in Women with Metabolic Syndrome Criteria

Sexual dimorphism accounts for significant differences in adipose tissue mass and distribution. However, how the crosstalk between visceral and ectopic fat depots occurs and which are the determinants of ectopic fat expansion and dysfunction remains unknown. Here, we focused on the impact of gender in the crosstalk between visceral and epicardial fat depots and the role of adipocytokines and high-sensitivity C-reactive protein (hs-CRP). A total of 141 outward patients (both men and women) with one or more defining criteria for metabolic syndrome (MetS) were consecutively enrolled. For all patients, demographic and clinical data were collected and ultrasound assessment of visceral adipose tissue (VFth) and epicardial fat (EFth) thickness was performed. Hs-CRP and adipocytokine levels were assessed by enzyme-linked immunosorbent assay (ELISA). Men were characterized by increased VFth and EFth (p-value < 0.001 and 0.014, respectively), whereas women showed higher levels of adiponectin and leptin (p-value < 0.001 for both). However, only in women VFth and EFth significantly correlated between them (p = 0.013) and also with leptin (p < 0.001 for both) and hs-CRP (p = 0.005 and p = 0.028, respectively). Linear regression confirmed an independent association of both leptin and hs-CRP with VFth in women, also after adjustment for age and MetS (p = 0.012 and 0.007, respectively). In conclusion, men and women present differences in epicardial fat deposition and systemic inflammation. An intriguing association between visceral/epicardial fat depots and chronic low-grade inflammation also emerged. In women Although a further validation in larger studies is needed, these findings suggest a critical role of sex in stratification of obese/dysmetabolic patients

Prognosis and Interplay of Cognitive Impairment and Sarcopenia in Older Adults Discharged from Acute Care Hospitals

Sarcopenia and cognitive impairment are associated with an increased risk of negative outcomes, but their prognostic interplay has not been investigated so far. We aimed to investigate the prognostic interaction of sarcopenia and cognitive impairment concerning 12-month mortality among older patients discharged from acute care wards in Italy. Our series consisted of 624 patients (age = 80.1 ± 7.0 years, 56.1% women) enrolled in a prospective observational study. Sarcopenia was defined following the European Working Group on Sarcopenia in Older People (EWGSOP) criteria. Cognitive impairment was defined as age- and education-adjusted Mini-Mental State Examination (MMSE) score < 24 or recorded diagnosis of dementia. The study outcome was all-cause mortality during 12-month follow-up. The combination of sarcopenia and cognitive ability was tested against participants with intact cognitive ability and without sarcopenia. Overall, 159 patients (25.5%) were identified as having sarcopenia, and 323 (51.8%) were cognitively impaired. During the follow-up, 79 patients (12.7%) died. After adjusting for potential confounders, the combination of sarcopenia and cognitive impairment has been found associated with increased mortality (HR = 2.12, 95% CI = 1.05-4.13). Such association was also confirmed after excluding patients with dementia (HR = 2.13, 95% CI = 1.06-4.17), underweight (HR = 2.18, 95% CI = 1.03-3.91), high comorbidity burden (HR = 2.63, 95% CI = 1.09-6.32), and severe disability (HR = 2.88, 95% CI = 1.10-5.73). The co-occurrence of sarcopenia and cognitive impairment may predict 1-year mortality in older patients discharged from acute care hospitals

General purpose data streaming platform for log analysis, anomaly detection and security protection

INFN-CNAF is one of the Worldwide LHC Computing Grid (WLCG) Tier-1 data centres, providing computing, networking and storage resources to a wide variety of scientific collaborations, not limited to the four LHC (Large Hadron Collider) experiments. The INFN-CNAF data centre will move to a new location next year. At the same time, the requirements from our experiments and users are becoming increasingly challenging and new scientific communities have started or will soon start exploiting our resources. Currently, we are reengineering several services, in particular our monitoring infrastructure, in order to improve the day-by-day operations and to cope with the increasing complexity of the use cases and with the future expansion of the centre. This scenario led us to implement a data streaming infrastructure designed to enable log analysis, anomaly detection, threat hunting, integrity monitoring and incident response. Such data streaming platform has been organised to manage different kinds of data coming from heterogeneous sources, to support multi-tenancy and to be scalable. Moreover, we will be able to provide an on demand end-to-end data streaming application to those users/communities requesting such kind of facility. The infrastructure is based on the Apache Kafka platform, which provides streaming of events at large scale, with authorization and authentication configured at the topic level for ensuring data isolation and protection. Data can be consumed by different applications, such as those devoted to log analysis, which provide the capability to index large amounts of data and implement appropriate access policies to inspect and visualise information. In this contribution we will present and motivate our technological choices for the definition of the infrastructure, we will describe its components and we will depict use cases which can be addressed with this platform

INFN Cloud Users and Projects Support, Training and Communication

Having a long tradition in state-of-the-art distributed IT technologies, in the last couple of years INFN made available to its users “INFN Cloud”: a cloud infrastructure and related services portfolio dedicated to the scientific communities supported by INFN. Given the distributed nature of the infrastructure as well as the considerable number of technical solutions provided to the INFN users, it is important to have a reliable user support service aimed to properly interact both with INFN Cloud users and administrators. As an added value, proper training activities have been defined and differentiated to different types of users and the training courses are integrated with a rich set of user guides and technical documentation. In this article, an overview of the INFN Cloud, its evolution to DataCloud project, and the support and training activities will be provided and presented

Emissione di sincrotrone e applicazioni astrofisiche

L'emissione di radiazione di sincrotrone è dovuta al moto relativistico di cariche elettriche accelerate in un campo magnetico. Nei casi astrofisici essa coinvolge essenzialmente la banda radio dello spettro elettromagnetico, poiché la frequenza caratteristica a cui avviene l'emissione dipende dall'intensità del campo magnetico stesso. Questo tipo di processo è detto non termico, in quanto gli elettroni presenti non sono all'equilibrio termico e la loro distribuzione di energia non segue la Maxwell-Boltzmann, ma sarà una legge di potenza. In questo elaborato si illustrano le principali caratteristiche di questo tipo di radiazione

General purpose data streaming platform for log analysis, anomaly detection and security protection

INFN-CNAF is one of the Worldwide LHC Computing Grid (WLCG) Tier-1 data centres, providing computing, networking and storage resources to a wide variety of scientific collaborations, not limited to the four LHC (Large Hadron Collider) experiments. The INFN-CNAF data centre will move to a new location next year. At the same time, the requirements from our experiments and users are becoming increasingly challenging and new scientific communities have started or will soon start exploiting our resources. Currently, we are reengineering several services, in particular our monitoring infrastructure, in order to improve the day-by-day operations and to cope with the increasing complexity of the use cases and with the future expansion of the centre. This scenario led us to implement a data streaming infrastructure designed to enable log analysis, anomaly detection, threat hunting, integrity monitoring and incident response. Such data streaming platform has been organised to manage different kinds of data coming from heterogeneous sources, to support multi-tenancy and to be scalable. Moreover, we will be able to provide an on demand end-to-end data streaming application to those users/communities requesting such kind of facility. The infrastructure is based on the Apache Kafka platform, which provides streaming of events at large scale, with authorization and authentication configured at the topic level for ensuring data isolation and protection. Data can be consumed by different applications, such as those devoted to log analysis, which provide the capability to index large amounts of data and implement appropriate access policies to inspect and visualise information. In this contribution we will present and motivate our technological choices for the definition of the infrastructure, we will describe its components and we will depict use cases which can be addressed with this platform