Issues of energy retrofitting of a modern public housing estates. The ‘Giorgio Morandi’ complex at Tor Sapienza, Rome, 1975-1979

Energy retrofitting of historical residential buildings represents today an interesting challenge of the building sector. This is true especially in Italy where great part of the national buildingstock dates back to pre-modern and modern times and, especially, to the decades between the 1960s and the 1980s. Most of these buildings, in fact, offerthermal performances that are inadequate to current requirements in terms of energy efficiency, human comfort as well as to seismic safety. This study focuses on the energy retrofitting of public housing estatessuch as the“Giorgio Morandi” complex at Tor Sapienza in Rome. The upgrading of this complex is outlined, taking into account issues of energy saving but, also, constraints related to the historical values of the buildings. Intervention options able to improve energy efficiency are therefore foreseeable only in strict observance of cultural heritage values, which entails a deep analysis and survey of the existence in order to identify respectful, correct and feasiblesolutions

Xenon Anesthesia Improves Respiratory Gas Exchanges in Morbidly Obese Patients

Background. Xenon-in-oxygen is a high density gas mixture and may improve PaO2/FiO2 ratio in morbidly obese patients uniforming distribution of ventilation during anesthesia. Methods. We compared xenon versus sevoflurane anesthesia in twenty adult morbidly obese patients (BMI > 35) candidate for roux-en-Y laparoscopic gastric bypass and assessed PaO2/FiO2 ratio at baseline, at 15 min from induction of anaesthesia and every 60 min during surgery. Differences in intraoperative and postoperative data including heart rate, systolic and diastolic pressure, oxygen saturation, plateau pressure, eyes opening and extubation time, Aldrete score on arrival to the PACU were compared by the Mann-Whitney test and were considered as secondary aims. Moreover the occurrence of side effects and postoperative analgesic demand were assessed. Results. In xenon group PaO2-FiO2 ratio was significantly higher after 60 min and 120 min from induction of anesthesia; heart rate and overall remifentanil consumption were lower; the eyes opening time and the extubation time were shorter; morphine consumption at 72 hours was lower; postoperative nausea was more common. Conclusions. Xenon anesthesia improved PaO2/FiO2 ratio and maintained its distinctive rapid recovery times and cardiovascular stability. A reduction of opioid consumption during and after surgery and an increased incidence of PONV were also observed in xenon group

A wearable sensor to monitor localized sweat rate as support tool for monitoring athletes' performances

Objectives We developed a wearable sensor for the real time measurement of sweat rate in localized areas of the human body. This sensor represents the first step in the development of a wearable sensor network capable to estimate the global sweat rate via an ad hoc algorithm. Such device would be used to monitor athletes' hydration status during training and improve their performances. Equipment and Methods For this study, we tested our sensor on thirteen football players during a cycling test on a cycle ergometer. The sweat rate sensor was compared to a medical device that, although measuring a different physiological process, provides discrete data based on the same working principle, i.e. the diffusion of the water vapour emitted from the skin. Results Our sensor has a working range up to 400 g/m2·h. The statistical analysis and the Bland-Altman plot proved that our sensor is comparable to the medical device used as gold standard. At low sweat rate, the bias is 3.4 g/m2·h with a standard deviation of 7.6 g/m2·h. At maximum sweat rates, the bias is 2.3 g/m2·h with a standard deviation 6.9 g/m2·h. The p values for the Bland-Altman plots at low and maximum sweat rate (0.1331 and 0.2477 obtained by Kolmogorov-Smirnov test, respectively) allow the hypothesis that there is a significant difference between our sweat rate sensor and the medical device to be rejected. Conclusion We presented a prototype of a wearable sweat rate sensor for localized measurements. The trials on thirteen athletes proved that the performance of our sensor is comparable to that of a commercial medical device. This sweat rate sensor can provide valuable information on athletes' hydration status

Internet traffic modeling by means of Hidden Markov Models

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Early identification of acute kidney injury after bariatric surgery: Role of NGAL and cystatin C

Background: The aim of our study was to evaluate plasmatic and urinary NGAL and serum cystatin C as early diagnostic markers of acute kidney injury in obese patients undergoing bariatric surgery. Methods: For this this prospective observational study, we recruited 23 patients undergoing gastric by-pass or sleeve gastrectomy, and admitted to the Low Dependence Unit after the surgery. Plasma NGAL (pNGAL), urinary NGAL (uNGAL), serum cystatin C, serum creatinine, and serum urea were measured before surgery as well as 10 h and 24 h after surgery. Mean values of pNGAL, uNGAL, cystatin C, creatinine, and urea concentrations of pre- and post-surgery periods were compared using Student’s t test for paired data. We also evaluated the presence of correlation between modifications of NGAL and cystatin C after surgery and fluid balance, hydration (ml/kg) and diuresis using Pearson’s coefficient of correlation. Results: No patient developed AKI according to the AKIN criteria. pNGAL was significantly higher at T10th than T0(p=0.004). There was no significant difference between uNGAL at T0 and T10th (p=0.53) and between uNGAL at T0 and T24th (p=0.31). uNGAL at T24th was significantly higher in comparison to T10th (p=0.024). uNGAL concentrations were normal in all patients at every time step. Cystatin C concentration did not increase after surgery. Serum creatinine level was significantly higher at T48th, despite being still within the normal range, when compared to T0 (p=0.038). Conclusion: Our study shows that pNGAL can reflect mild tubular damage as its levels increase within a few hours from surgery and return to normal limits afterwards. Concerning uNGAL, there is a minimal increase at T24th, when NGAL concentration in plasma has already decreased. Serum cystatin C does not show any relevant kidney changes, or at least, no more than those ones shown by pNGAL