An evaluation of unit nonresponse bias in the Italian Households Budget Survey

Die Auswirkungen von Antwortverweigerung sind in der Literatur zur Umfrageforschung vielfach diskutiert worden. Antwortverweigerung führt zu einer Erhöhung der Stichprobenvarianz, deren Ausmaß über die Schätzung der durch Antwortverweigerung verursachten Verzerrung gemessen werden kann. Wenn Befragte nur unvollkommen kooperieren, führt dies zu ungenauen oder unvollständigen Informationen, die nicht zum Zweck einer Schätzung herangezogen werden können. Istat streicht seit 1991 alle Haushalte mit inkompatiblen Daten für Ausgaben und Einkommen aus seiner Stichprobe. Die Verfasser bezeichnen diese Gruppe als "unzuverlässige Respondenten". Solche Daten eignen sich zwar nicht für Schätzungen, sie erlauben jedoch Rückschlüsse auf die Gruppe der Antwortverweigerer. Dem liegt die Annahme zu Grunde, dass die Gruppe der unzuverlässigen Respondenten eher der Gruppe der Antwortverweigerer ähnelt als der Gruppe der Antwortenden. Die Verfasser berichten über den Versuch, den durch Antwortverweigerung entstandenen Bias im Italian Household Budget Survey 1995 zu bestimmen. Hierzu wurde keine gesonderte Untersuchung der Nonrespondenten durchgeführt. (ICEÜbers)"The effect of nonresponse is a crucial aspect which has received considerable attention in literature. Nonresponse causes an increase in sampling variance and the estimates of units nonresponse bias are useful to give a concrete measure of this increase. Scarce co-operation of respondents gives inaccurate or incomplete information, and this part of the answers can't be used in the estimation. Since 1991, Istat erases from its sample file all households with incompatible data on expenditure and income. The authors call this the 'UR (Unreliable Respondents) sub population'. UR data can't be used to build estimates, but can be used to give approximate information an NR. The idea is that, concerning behaviour, the NR population is more similar to UR than to R. The results of an attempt to evaluate unit nonresponse bias in the 1995 Italien Household Budget Survey (HBS) are shown in this paper. These results were obtained without performing a specific survey on nonrespondents." (author's abstract

Analisi e caratterizzazione di componenti, circuiti e sottoparti per la realizzazione di un alimentatore AC/DC resistente a radiazioni e campi magnetici intensi

La Tesi, interamente realizzata presso la ditta C.A.E.N. S.p.A., consiste nell’analisi e nella caratterizzazione dei vari moduli che costituiscono il sistema A3486, un alimentatore switching resistente a campi magnetici elevati e radiazioni di varia natura; tale caratteristica permette il suo utilizzo in particolari esperimenti di fisica nucleare eseguiti presso il C.E.R.N. di Ginevra. Dopo un’introduzione che illustra le caratteristiche degli alimentatori switching e dei trasformatori ad alta frequenza, l’elaborato propone la descrizione del sistema, in cui vengono messe in evidenza le caratteristiche principali e le specifiche. Successivamente vengono riportate le misure, alle quali ho collaborato, ed i conseguenti risultati ottenuti che hanno portato alla realizzazione del modello definitivo

Clinical Management of Critical COVID-19 Patients: Insights from the Literature and "On the Field" Experience

AbstractThe recent outbreak of the coronavirus disease (COVID-19) is a health emergency all over the world. Several health care professionals are currently putting their best efforts to deal with this situation. The aim of this review is to report insights from the literature and "on the field" experience in clinical management of critical COVID-19 patients. Respiratory support varies from high flow nasal cannula (HFNC) to noninvasive and invasive mechanical ventilation, often associated with nitric oxide, prone position, and extracorporeal membrane oxygenation (ECMO). Experienced specialists have to manage the airways minimizing any contamination and virus spread. The hemodynamic management of critical COVID-19 patients requires not only an accurate fluid strategy, but also an appropriate use of vasopressors and inotropes. Various adjuvant treatments have been proposed: antiviral drugs, immunomodulators, anticoagulants, antibiotics, and nutrition

Deep reinforcement learning for quantum multiparameter estimation

Estimation of physical quantities is at the core of most scientific research, and the use of quantum devices promises to enhance its performances. In real scenarios, it is fundamental to consider that resources are limited, and Bayesian adaptive estimation represents a powerful approach to efficiently allocate, during the estimation process, all the available resources. However, this framework relies on the precise knowledge of the system model, retrieved with a fine calibration, with results that are often computationally and experimentally demanding. We introduce a model-free and deep-learning-based approach to efficiently implement realistic Bayesian quantum metrology tasks accomplishing all the relevant challenges, without relying on any a priori knowledge of the system. To overcome this need, a neural network is trained directly on experimental data to learn the multiparameter Bayesian update. Then the system is set at its optimal working point through feedback provided by a reinforcement learning algorithm trained to reconstruct and enhance experiment heuristics of the investigated quantum sensor. Notably, we prove experimentally the achievement of higher estimation performances than standard methods, demonstrating the strength of the combination of these two black-box algorithms on an integrated photonic circuit. Our work represents an important step toward fully artificial intelligence-based quantum metrology

Gel piastrinico. Trattamento del piede diabetico e dell’osteomielite fistolizzata. Revisione della letteratura e nostra esperienza in 61 casi clinici

GEL PIASTRINICO: TRATTAMENTO DEL PIEDE DIABETICO E DELL’OSTEOMIELITE FISTOLIZZATA. REVISIONE DELLA LETTERATURA E NOSTRA ESPERIENZA IN 61 CASI CLINICI Introduzione: la nostra esperienza evidenzia l’utilità del gel piastrinico (GP) nel trattamento ambulatoriale delle piaghe torpide della pianta del piede in paziente diabetico e delle ulcerazioni torpide che richiedevano periodi lunghissimi di medicazioni complesse, senza raggiungere il risultato atteso. Materiali e Metodi: la metodica personale prevede il curettage dopo disinfezione e debridement della piaga, l’inoculazione di 1-4 UI di insulina pronta alla base del cratere ulcerativo e quindi l’applicazione di 5 ml di GP con 1 ml di Trombina autologa attivata. L’applicazione si esegue facendo gocciolare il concentrato piastrinico su Hyalofill-F Fidia® Italia sul quale si fa, quindi, gocciolare l’attivatore ottenendo un panno morbido, elastico-gelatinoso, pronto a riempire la cavità da trattare. Il supporto inerte riassorbibile in acido ialuronico impedisce la dispersione della parte liquida o non completamente gelificata, ricca dei fattori di crescita (PDGF, TGF, EGF) che stimolano la moltiplicazione dei fibroblasti i quali aumentano di numero e depositano matrice connettivale, trasformando la piaga torpida con la fioritura dei bottoni di granulazione. In caso di ferite più piccole o man mano che l’ampiezza della ferita si riduce, il prodotto può essere aliquotato e congelato per successive somministrazioni. Nel caso di paziente affetto da ulcerazione da osteomielite occorre un lungo periodo di terapia antibiotica parenterale con Ampicillina-Sulbactam o Piperacillina-Tazobactam o Ertapenem o Meropenem associata a Vancomicina, oppure, alternativamente Daptomicina. Discussione: in generale, la terapia deve essere mirata sulla base dell’isolamento del germe patogeno, ma spesso l’infezione è polimicrobica e quindi si somministra una terapia empirica ad ampio spettro. Principio guida nella terapia empirica è la somministrazione di antibiotici contro lo Staphylococcus aureus meticillino resistente (MRSA). Nei pazienti ambulatoriali è essenziale tenere in considerazione la presenza di germi meticillino resistente associati alla comunità di appartenenza (CA-MRSA) e quindi occorrono colture batteriche ripetute. Conclusioni: l’approccio multidisciplinare tra chirurgo, immunotrasfusionista, infettivologo, dermatologo, ortopedico, diabetologo e cardiologo, risolve brillantemente la problematica. Lo stretto coordinamento tra ambulatorio chirurgico ed il centro trasfusionale, evita inutili attese al Paziente, accorcia i tempi di esecuzione della medicazione, abbatte i costi per l’impiego di materiali e diventa conveniente rispetto al trattamento tradizionale.Our study proves the usefulness of platelet gel in the treatment of the diabetic foot. We started in January 2006 to treat diabetic wounds of the foot in the outpatients’ surgical department with encouraging results. Despite its expensive and complex preparation, the platelet gel is useful and convenient because it succeeds in shortening the ambulatory treatment period. Besides, in our opinion, the multidisciplinary approach of this treatment is rather important: actually, it implies the cooperation of dermatologist, surgeon, orthopaedist, immunologist, diabetologist and, if necessary, the cardiologist. That is why it reduces wastes of work-time and the expenses for consultants, medications and dressing material

Minimally invasive laparoscopic and robot-assisted emergency treatment of strangulated giant hiatal hernias: report of five cases and literature review

Background Giant hiatal hernia (GHH) is a condition where one-third of the stomach migrates into the thorax. Nowadays, laparoscopic treatment gives excellent postoperative outcomes. Strangulated GHH is rare, and its emergent repair is associated with significant morbidity and mortality rates. We report a series of five cases of strangulated GHH treated by a minimally invasive laparoscopic and robot-assisted approach, together with a systematic review of the literature. Methods During 10 years (December 2009–December 2019), 31 patients affected by GHH were treated by robot-assisted or conventional laparoscopic surgical approach. Among them, five cases were treated in an emergency setting. We performed a PubMed MEDLINE search about the minimally invasive emergent treatment of GHH, selecting 18 articles for review. Results The five cases were male patients with a mean age of 70 ± 18 years. All patients referred to the emergency service complaining of severe abdominal and thoracic pain, nausea and vomiting. CT scan and endoscopy were the main diagnostic tools. All patients showed stable hemodynamic conditions so that they could undergo a minimally invasive attempt. The surgical approach was robotic-assisted in three patients (60%) and laparoscopic in two (40%). Patients reported no complications or recurrences. Conclusion Reviewing current literature, no general recommendations are available about the emergent treatment of strangulated hiatal hernia. Acute mechanical outlet obstruction, ischemia of gastric wall or perforation and severe bleeding are the reasons for an emergent surgical indication. In stable conditions, a minimally invasive approach is often feasible. Moreover, the robot-assisted approach, allowing a stable 3D view and using articulated instruments, represents a reasonable option in challenging situations

How skill expertise shapes the brain functional architecture: an fMRI study of visuo-spatial and motor processing in professional racing-car and naïve drivers

The present study was designed to investigate the brain functional architecture that subserves visuo-spatial and motor processing in highly skilled individuals. By using functional magnetic resonance imaging (fMRI), we measured brain activity while eleven Formula racing-car drivers and eleven ‘naïve’ volunteers performed a motor reaction and a visuo-spatial task. Tasks were set at a relatively low level of difficulty such to ensure a similar performance in the two groups and thus avoid any potential confounding effects on brain activity due to discrepancies in task execution. The brain functional organization was analyzed in terms of regional brain response, inter-regional interactions and blood oxygen level dependent (BOLD) signal variability. While performance levels were equal in the two groups, as compared to naïve drivers, professional drivers showed a smaller volume recruitment of task-related regions, stronger connections among task-related areas, and an increased information integration as reflected by a higher signal temporal variability. In conclusion, our results demonstrate that, as compared to naïve subjects, the brain functional architecture sustaining visuo-motor processing in professional racing-car drivers, trained to perform at the highest levels under extremely demanding conditions, undergoes both ‘quantitative’ and ‘qualitative’ modifications that are evident even when the brain is engaged in relatively simple, non-demanding tasks. These results provide novel evidence in favor of an increased ‘neural efficiency’ in the brain of highly skilled individuals

Experimental multiparameter quantum metrology in adaptive regime

Relevant metrological scenarios involve the simultaneous estimation of multiple parameters. The fundamental ingredient to achieve quantum-enhanced performances is based on the use of appropriately tailored quantum probes. However, reaching the ultimate resolution allowed by physical laws requires non trivial estimation strategies both from a theoretical and a practical point of view. A crucial tool for this purpose is the application of adaptive learning techniques. Indeed, adaptive strategies provide a flexible approach to obtain optimal parameter-independent performances, and optimize convergence to the fundamental bounds with limited amount of resources. Here, we combine on the same platform quantum-enhanced multiparameter estimation attaining the corresponding quantum limit and adaptive techniques. We demonstrate the simultaneous estimation of three optical phases in a programmable integrated photonic circuit, in the limited resource regime. The obtained results show the possibility of successfully combining different fundamental methodologies towards transition to quantum sensors applications

It’s not all in your car: functional and structural correlates of exceptional driving skills in professional racers

Driving is a complex behavior that requires the integration of multiple cognitive functions. While many studies have investigated brain activity related to driving simulation under distinct conditions, little is known about the brain morphological and functional architecture in professional competitive driving, which requires exceptional motor and navigational skills. Here, 11 professional racing-car drivers and 11 “naïve” volunteers underwent both structural and functional brain magnetic resonance imaging (MRI) scans. Subjects were presented with short movies depicting a Formula One car racing in four different official circuits. Brain activity was assessed in terms of regional response, using an Inter-Subject Correlation (ISC) approach, and regional interactions by mean of functional connectivity. In addition, voxel-based morphometry (VBM) was used to identify specific structural differences between the two groups and potential interactions with functional differences detected by the ISC analysis. Relative to non-experienced drivers, professional drivers showed a more consistent recruitment of motor control and spatial navigation devoted areas, including premotor/motor cortex, striatum, anterior, and posterior cingulate cortex and retrosplenial cortex, precuneus, middle temporal cortex, and parahippocampus. Moreover, some of these brain regions, including the retrosplenial cortex, also had an increased gray matter density in professional car drivers. Furthermore, the retrosplenial cortex, which has been previously associated with the storage of observer-independent spatial maps, revealed a specific correlation with the individual driver's success in official competitions. These findings indicate that the brain functional and structural organization in highly trained racing-car drivers differs from that of subjects with an ordinary driving experience, suggesting that specific anatomo-functional changes may subtend the attainment of exceptional driving performance