4,602 research outputs found
Causality in concurrent systems
Concurrent systems identify systems, either software, hardware or even
biological systems, that are characterized by sets of independent actions that
can be executed in any order or simultaneously. Computer scientists resort to a
causal terminology to describe and analyse the relations between the actions in
these systems. However, a thorough discussion about the meaning of causality in
such a context has not been developed yet. This paper aims to fill the gap.
First, the paper analyses the notion of causation in concurrent systems and
attempts to build bridges with the existing philosophical literature,
highlighting similarities and divergences between them. Second, the paper
analyses the use of counterfactual reasoning in ex-post analysis in concurrent
systems (i.e. execution trace analysis).Comment: This is an interdisciplinary paper. It addresses a class of causal
models developed in computer science from an epistemic perspective, namely in
terms of philosophy of causalit
Riqualifcazione urbana, rilievo architettonico e progettazione partecipata a Pontedera
La tesi affronta il tema della riqualificazione di due differenti spazi urbani a Pontedera secondo due approcci diversi: quello della progettazione partecipata e quello del rilievo architettonico.
Nel primo caso, oggetto di studio è stato il giardino Bella di Mai, per il quale, oltre alla stesura dello stato attuale è stato proposto un processo partecipativo per la riqualificazione dello stesso attraverso il coinvolgimento dei cittadini, da attuarsi in un futuro con l'ausilio dell'amministrazione comunale.
Nel secondo caso lo spazio urbano considerato è Piazza Martiri della Libertà per il quale sono stati eseguiti i rilievi di tutti i prospetti degli edifici prospicienti la piazza e della pianta. Per questa si è proposta una riqualificazione dell'area introducendo una completa pedonalizzazione, possibile graze alla deviazione del traffico, oggi transitante per la piazza, in una nuova strada da realizzare lungo l'argine del fiume Era; nello stesso tempo il transito è consentito solo ad alcune categorie di veicoli, i residenti e quelli per l'approvvigionamento dei negozi, ed in alcuni orari della giornata
Embedded techniques for choosing the parameter in Tikhonov regularization
This paper introduces a new strategy for setting the regularization parameter
when solving large-scale discrete ill-posed linear problems by means of the
Arnoldi-Tikhonov method. This new rule is essentially based on the discrepancy
principle, although no initial knowledge of the norm of the error that affects
the right-hand side is assumed; an increasingly more accurate approximation of
this quantity is recovered during the Arnoldi algorithm. Some theoretical
estimates are derived in order to motivate our approach. Many numerical
experiments, performed on classical test problems as well as image deblurring
are presented
Adding Recognition Discriminability Index to the Delayed Recall Is Useful to Predict Conversion from Mild Cognitive Impairment to Alzheimer's Disease in the Alzheimer's Disease Neuroimaging Initiative
Background: Ongoing research is focusing on the identification of those individuals with mild cognitive impairment (MCI) who are most likely to convert to Alzheimer's disease (AD). We investigated whether recognition memory tasks in combination with delayed recall measure of episodic memory and CSF biomarkers can predict MCI to AD conversion at 24-month follow-up. Methods: A total of 397 amnestic-MCI subjects from Alzheimer's disease Neuroimaging Initiative were included. Logistic regression modeling was done to assess the predictive value of all RAVLT measures, risk factors such as age, sex, education, APOE genotype, and CSF biomarkers for progression to AD. Estimating adjusted odds ratios was used to determine which variables would produce an optimal predictive model, and whether adding tests of interaction between the RAVLT Delayed Recall and recognition measures (traditional score and d-prime) would improve prediction of the conversion from a-MCI to AD. Results: 112 (28.2%) subjects developed dementia and 285 (71.8%) subjects did not. Of the all included variables, CSF Aβ1-42 levels, RAVLT Delayed Recall, and the combination of RAVLT Delayed Recall and d-prime were predictive of progression to AD (χ2 = 38.23, df = 14, p < 0.001). Conclusions: The combination of RAVLT Delayed Recall and d-prime measures may be predictor of conversion from MCI to AD in the ADNI cohort, especially in combination with amyloid biomarkers. A predictive model to help identify individuals at-risk for dementia should include not only traditional episodic memory measures (delayed recall or recognition), but also additional variables (d-prime) that allow the homogenization of the assessment procedures in the diagnosis of MCI.Fil: Russo, María Julieta. Fundación para la Lucha Contra las Enfermedades Neurológicas de la Infancia. Instituto de Investigaciones Neurológicas "Raúl Carrea"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Campos, Jorge. Fundación para la Lucha Contra las Enfermedades Neurológicas de la Infancia. Instituto de Investigaciones Neurológicas "Raúl Carrea"; ArgentinaFil: Vázquez, Silvia. Fundación para la Lucha Contra las Enfermedades Neurológicas de la Infancia. Instituto de Investigaciones Neurológicas "Raúl Carrea"; ArgentinaFil: Sevlever, Gustavo. Fundación para la Lucha Contra las Enfermedades Neurológicas de la Infancia. Instituto de Investigaciones Neurológicas "Raúl Carrea"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Allegri, Ricardo Francisco. Fundación para la Lucha Contra las Enfermedades Neurológicas de la Infancia. Instituto de Investigaciones Neurológicas "Raúl Carrea"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Role of uL3 in Multidrug Resistance in p53-Mutated Lung Cancer Cells
Cancer is one of the most common causes of death among adults. Chemotherapy is crucial in determining patient survival and quality of life. However, the development of multidrug resistance (MDR) continues to pose a significant challenge in the management of cancer. In this study, we analyzed the role of human ribosomal protein uL3 (formerly rpL3) in multidrug resistance. Our studies revealed that uL3 is a key determinant of multidrug resistance in p53-mutated lung cancer cells by controlling the cell redox status. We established and characterized a multidrug resistant Calu-6 cell line. We found that uL3 down-regulation correlates positively with multidrug resistance. Restoration of the uL3 protein level re-sensitized the resistant cells to the drug by regulating the reactive oxygen species (ROS) levels, glutathione content, glutamate release, and cystine uptake. Chromatin immunoprecipitation experiments and luciferase assays demonstrated that uL3 coordinated the expression of stress-response genes acting as transcriptional repressors of solute carrier family 7 member 11 (xCT) and glutathione S-transferase α1 (GST-α1), independently of Nuclear factor erythroid 2-related factor 2 (Nrf2). Altogether our results describe a new function of uL3 as a regulator of oxidative stress response genes and advance our understanding of the molecular mechanisms underlying multidrug resistance in cancers
On Krylov projection methods and Tikhonov regularization
In the framework of large-scale linear discrete ill-posed problems, Krylov projection methods represent an essential tool since their development, which dates back to the early 1950\u2019s. In recent years, the use of these methods in a hybrid fashion or to solve Tikhonov regularized problems has received great attention especially for problems involving the restoration of digital images. In this paper we review the fundamental Krylov-Tikhonov techniques based on Lanczos bidiagonalization and the Arnoldi algorithms. Moreover, we study the use of the unsymmetric Lanczos process that, to the best of our knowledge, has just marginally been considered in this setting. Many numerical experiments and comparisons of different methods are presented
Dynamic investigation on the Mirandola bell tower in post-earthquake scenarios
After the seismic events of the 20th and 29th of May 2012 in Emilia (Italy), most of the monumental and historic buildings of the area were severely damaged. In a few structures, partial collapse mechanisms were observed (e.g. façade tilting, out-of-plane overturning of panels…). This paper presents the case-study of the bell tower of the Santa Maria Maggiore cathedral, located in Mirandola (Italy). The dynamic response of the structure was evaluated through operational modal analysis using ambient vibrations, a consolidated non-destructive procedure that estimates the dynamic parameters of the bell-tower. The dynamic tests were carried out in pre-intervention and post-intervention conditions in order to understand the sensitivity of dynamic measurements to safety interventions. Furthermore, a comparative study is made with similar cases of undamaged masonry towers up to the 6th mode. Finally, an investigation on the state of connections and of the building itself is carried out via FE model updating
Invasive meningococcal disease in the Veneto region of Italy: A capture-recapture analysis for assessing the effectiveness of an integrated surveillance system
open8noBACKGROUND:
Epidemiology of Neisseria meningitidis has been changing since the introduction of universal vaccination programmes against meningococcal serogroup C (MenC) and meningococcal serogroup B (MenB) has now become dominant. This study aimed to analyse the cases reported in institutional data recording systems to estimate the burden of invasive meningococcal diseases (IMDs) and assess the effectiveness of surveillance in Veneto region (Italy).
METHODS:
Analysis was performed from 2007 to 2014 on data recorded in different systems: Mandatory Notification System, National Surveillance of Invasive Bacterial Diseases System and Laboratories Surveillance System (LSS), which were pooled into a combined surveillance system (CSS) and hospital discharge records (HDRs). A capture-recapture method was used and completeness of each source estimated. Number of cases with IMD by source of information and year, incidence of IMD by age group, case fatality rate (CFR) and distribution of meningococcal serogroups by year were also analysed.
RESULTS:
Combining the four data systems enabled the identification of 179 confirmed cases with IMD, achieving an overall sensitivity of 94.7% (95% CI: 90.8% to 98.8%), while it was 76.7% (95% CI: 73.6% to 80.1%) for CSS and 77.2% (95% CI: 74.1% to 80.6%) for HDRs. Typing of isolates was done in 80% of cases, and 95.2% of the typed cases were provided by LSS. Serogroup B was confirmed in 50.3% of cases. The estimated IMD notification rate (cases with IMD diagnosed and reported to the surveillance systems) was 0.48/100 000 population, and incidence peaked at 6.2/100 000 in children aged <1 year old (60.9% due to MenB), and increased slightly in the age group between 15 and 19 years (1.1/100 000). A CFR of 14% was recorded (8.7% in paediatric age).
CONCLUSIONS:
Quality of surveillance systems relies on case ascertainment based on serological characterisation of the circulating strains by microbiology laboratories. All available sources should be routinely combined to improve the epidemiology of IMD and the information used by public health departments to conduct timely preventive measures.openBaldovin, Tatjana; Lazzari, Roberta; Cocchio, Silvia; Furlan, Patrizia; Bertoncello, Chiara; Saia, Mario; Russo, Francesca; Baldo, VincenzoBaldovin, Tatjana; Lazzari, Roberta; Cocchio, Silvia; Furlan, Patrizia; Bertoncello, Chiara; Saia, Mario; Russo, Francesca; Baldo, Vincenz
Parametros biológicos y morfología de estados juveniles de Adurgoa gonagra (Klug) (Hym.., Argidae)
p.189-192La mosca sierra, Adurgoa gonagra, que se alimenta externamente de follaje, fue criada en laboratorio con hojas de Senna péndula var. paludicola, realizándose una descripción detallada de los estados juveniles (huevo, estadios larvales y pupa). El número de estadios larvales fue determinado de acuerdo con la ley de Dyar, tomando en cuenta el ancho de la cápsula cefálica. También se analizan características biológicas como duración y mortalidad de los diferentes estadios
Contractual Limits to the Right to Strike in the Era of Crisis. The Italian Case with some Comparative Reliefs (France and the U.K.)*. WP CSDLE “Massimo D’Antona”.INT – 125/2015
The economic crisis, the outsourcing of production, and globalization have produced significant changes in industrial relations and trade unions. Because of these changes, dissent – which is usually manifested through the exercise of the right to strike and the spontaneous actions – faces certain limitations set by trade union clauses, which have been recently introduced to govern industrial relations (e.g. industrial peace clauses and enforceability ones). In order to deal with the foregoing questions, the present paper provides an analysis of the notion of strike through supranational sources (Introduction, Silvia Donà, Università di Roma La Sapienza), followed by an examination of what is meant by “holding the right to strike” in Italy. The paper goes on to investigate the way this right is exercised (Section 1, Lilli Carollo, Università di Roma La Sapienza) and the clauses which have been devised to narrow down its exercise through the years (Section 2, Anna Rota, Università di Bologna), and concludes with an overview of the consequences arising from the violations of these clauses (Section 3, Marianna Russo, Università di Roma La Sapienza). With a view of better understanding the peculiarities of the Italian rules concerning the right to strike, a comparison will be provided with France and the UK (Marta Filippi, Università di Roma La Sapienza)
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