Design-time formal verification for smart environments: an exploratory perspective

Smart environments (SmE) are richly integrated with multiple heterogeneous devices; they perform the operations in intelligent manner by considering the context and actions/behaviors of the users. Their major objective is to enable the environment to provide ease and comfort to the users. The reliance on these systems demands consistent behavior. The versatility of devices, user behavior and intricacy of communication complicate the modeling and verification of SmE's reliable behavior. Of the many available modeling and verification techniques, formal methods appear to be the most promising. Due to a large variety of implementation scenarios and support for conditional behavior/processing, the concept of SmE is applicable to diverse areas which calls for focused research. As a result, a number of modeling and verification techniques have been made available for designers. This paper explores and puts into perspective the modeling and verification techniques based on an extended literature survey. These techniques mainly focus on some specific aspects, with a few overlapping scenarios (such as user interaction, devices interaction and control, context awareness, etc.), which were of the interest to the researchers based on their specialized competencies. The techniques are categorized on the basis of various factors and formalisms considered for the modeling and verification and later analyzed. The results show that no surveyed technique maintains a holistic perspective; each technique is used for the modeling and verification of specific SmE aspects. The results further help the designers select appropriate modeling and verification techniques under given requirements and stress for more R&D effort into SmE modeling and verification researc

Arterial switch and neurological outcomes: a retrospective study of medical records

Despite being uncommon, survivors of neonatal cardiac surgery for complex congenital heart defects may face delays in various developmental domains, along with persistent subtle neurological deficits throughout their lifetime. Research is ongoing to determine the full extent and scope of these impairments. This study was performed to investigate neonatal and perioperative factors associated with neurodevelopmental differences in neonates who underwent arterial switch operation for transposition of the great arteries. Data collected retrospectively from neonates undergoing arterial switch operation from September 2017 to August 2020 at a single, quaternary institution, included perinatal history, perioperative data, and outpatient documentation. Primary outcome measures were neurological outcomes. The results showed that 26 neonates (65% male, 17/26) were included in this study, with a mean gestational age of 38 weeks (range 32–41 weeks) and a median birth weight of 3.3 kg (range 1.86–4.74 kg). Racial demographics included Caucasian in 8/26 (30.8%), Black in 2/26 (7.7%), Asian in 1/26 (3.8%), biracial in 9/26 (34.6%), and unspecified in 6/26 (23.1%). 46% (12/26) were of Hispanic ethnicity. No participant had a genetic diagnosis. Cardiac diagnoses included transposition of the great arteries with intact ventricular septum (17/26, 65%), with ventricular septal defect (8/26, 31%), and with double outlet right ventricle (1/26, 4%). Prenatal detection occurred in 12/26 (46%) patients. High-risk mortality risk factors, as categorized by Society of Thoracic Surgery Congenital Heart Surgery Database, were present in 22/26 (85%). Balloon atrio-septostomy was performed in 16/26 (62%). Arterial switch operation was performed at a mean age of 7.7 days (range 3–39 days). The average oxygen saturation 24 hours before BAS was 69% (range 50–87%), and the average oxygen saturation 24 hours before the arterial switch operation was 85% (range 75–92%). The mean cardiopulmonary bypass duration was 252 minutes (range 125–460 minutes), and the mean aortic cross-clamp duration was 138 minutes (range 61–266 minutes). No neonates required extracorporeal membrane oxygenation perioperatively. A shorter duration of cardiopulmonary bypass (P = 0.004) and cross-clamp time (P = 0.015) and the need for BAS (P = 0.043) were significantly associated with developmental delay in early childhood. The Apgar score, birth weight, microcephaly, need for preoperative mechanical ventilation, and age at the time of the arterial switch operation were not associated with developmental delay. The survival rate was 100% at a median follow-up of 3 years (range 2–5 years). These findings suggest that an arterial switch for transposition of the great arteries can be performed with satisfactory outcomes; however, this study supports the need for more neurodevelopmental-focused care through both the neonatal period and long-term follow-up. Neurodevelopmental monitoring of high-risk neonates with transposition of the great arteries before and after cardiac interventions is critically important, as it guides decisions on the need for advanced neuroimaging and the risk for neurodevelopmental impairments in the long term

Acute pressure overload of the right ventricle. Comparison of two models of right-left shunt. Pulmonary artery to left atrium and right atrium to left atrium: experimental study

<p>Abtract</p> <p>Background</p> <p>In right ventricular failure (RVF), an interatrial shunt can relieve symptoms of severe pulmonary hypertension by reducing right ventricular preload and increasing systemic flow. Using a pig model to determine if a pulmonary artery - left atrium shunt (PA-LA) is better than a right atrial - left atrial shunt (RA-LA), we compared the hemodynamic effects and blood gases between the two shunts.</p> <p>Methods</p> <p>Thirty, male Large White pigs weighting in average 21.3 kg ± 0.7 (SEM) were divided into two groups (15 pigs per group): In group 1, banding of the pulmonary artery and a pulmonary artery to left atrium shunt with an 8 mm graft (PA-LA) was performed and in group 2 banding of the pulmonary artery and right atrial to left atrial shunt (RA-LA) with a similar graft was performed. Hemodynamic parameters and blood gases were measured from all cardiac chambers in 10 and 20 minutes, half and one hour interval from the baseline (30 min from the banding). Cardiac output and flow of at the left anterior descending artery was also monitored.</p> <p>Results</p> <p>In both groups, a stable RVF was generated. The PA-LA shunt compared to the RA-LA shunt has better hemodynamic performance concerning the decreased right ventricle afterload, the 4 fold higher mean pressure of the shunt, the better flow in left anterior descending artery and the decreased systemic vascular resistance. Favorable to the PA-LA shunt is also the tendency - although not statistically significant - in relation to central venous pressure, left atrial filling and cardiac output.</p> <p>Conclusion</p> <p>The PA-LA shunt can effectively reverse the catastrophic effects of acute RVF offering better hemodynamic characteristics than an interatrial shunt.</p

Durata dell'immunità antitetanica in relazione al numero di dosi di vaccino

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