APAP titration in patients with mild to moderate OSAS and periodic limb movement syndrome

(APAP) titration in a partially attended setting; 2) to verify whether APAP performance depends on the apneahypopnea and periodic limb movement indexes (PLMI). Methods. 65 CPAP naïve subjects with a sleep disorder of breathing and daytime sleepiness underwent a standard polysomnography (first night), APAP titration (second night, partially attended), and a standard polysomnography using continuous positive airway pressure (CPAP) at the effective pressure (Peff) established from the APAP titration (third night) in a sleep disorder laboratory in a 400-bed community hospital. We examined the apnea-hypopnea index (AHI), sleep stages, arousals induced by respiratory events (RESPa) and PLM (PLMa), and oxygen saturation during the first and third nights on CPAP at the Peff. Patients were divided into three groups according to their AHI and PLMI. Results. At the Peff defined using APAP on the third night, the mean AHI dropped from 29.6 ± 21.8 to 3.1 ± 3.4, and the RESPa index from 16.5 ± 16.2 to 1.7 ± 2.6. No differences emerged in sleep stages or spontaneous arousals (first vs third night). Overall, 92% of the patients met the standard for an acceptable outcome of positive pressure titration. Baseline AHI and PLMI did not affect the outcome of titration. Conclusions. In patients with mild to moderate OSAS and PLMS, APAP titration enables the optimal fixed pressure for CPAP home therapy to be determined in at least 90% of patients

NUMERICAL ANALYSIS OF A SMALL TURBO-CHARGED SPARK-IGNITION ENGINE

ABSTRACT The reduction of green-house gas emissions, that is the reduction of engine fuel consumption, is becoming a primary requirement for the automotive industry as well as meeting current and future emission legislations. Performing high torque values with small displacement engines, the so-called "downsizing", permits, in general, to limit some typical engine losses (for instance: pumping and friction losses), increasing the overall engine efficiency. This means to improve vehicle fuel economy and, as a consequence, the CO 2 emissions avoiding a performance decrease. In this paper, the behavior of a small displacement turbocharged spark-ignition engine prototype, for medium size passenger cars, has been analyzed. 3-D numerical simulations have been carried out in order to achieve a lot of information on engine performance and control parameters. Thus, at different engine operating points, intake and exhaust manifold pressure, volumetric efficiency, high pressure curves, the flow field of the fresh charge within the cylinder, the air to fuel ratio distribution, the residual gas fraction distribution and so long have been calculated. Since, as usual, the turbocharged version of the engine under study derives from an existing naturally aspirated engine, the purpose of this investigation is to obtain a detailed picture of the variations produced by turbo-charging on engine main parameters. The increase of knock risk due to higher cylinder pressures has been evaluated as well. Thanks to the three dimensional analysis, sound information have been obtained, so that suggestions for modifying some geometric engine parameters, according to the variations imposed by turbo-charging, have been proposed. The model utilized in this study has been validated by comparing the obtained results to the measured data provided by the research center of the engine manufacturer. INTRODUCTION In the last fifteen years, in Europe, great steps forward on the way of containing the emission levels from road transportation vehicles have been made. The EURO 4 emission standard has imposed very low levels for the so called regulated emissions produced by both spark-ignition and compression ignition engines. The recent signature of Kyoto protocol has shifted the attention to the amounts of the greenhouse gas CO 2 released in the atmosphere by the internal combustion engines. The European car manufacturers reached an agreement for about 20% reduction of the fleet CO 2 levels in a few years. This target represents a demanding challenge for present sparkignition engines. To improve engine fuel economy, at a given power output, means to increase the energy conversion efficiency. It is known that the spark-ignition engine efficiency is variable in the engine operating map, in particular, efficiency dramatically falls with load due to the additional losses introduced by the throttle valve during the intake stroke. Since a road engine is very frequently run under low load and low speed conditions, the improvement of the fuel consumption in these operating points leads to a significant improvement of fuel economy hence to a significant reduction of the amount of CO 2 produced. Low swept volume engines must run at higher loads, so pumping losses are reduced by the de-throttling effect

Severe Acute Dyspnoea of Extra-Thoracic Origin: Experience with Three Primary Thyroid Lymphomas (PTL)

Objectives: To recall the common clinical presenting features of and guide the diagnostic procedures of primary thyroid lymphomas (PTL). Materials and methods: We report on three patients developing an acute dyspnoea and fast evolving neck mass in the thyroid caused by a PTL occurring in our regional hospital in Switzerland between 2009 and 2013. Results: PTL causes a neck mass, dyspnoea and dysphonia and responds well to chemotherapy. Mortality is due to relapse or infectious complications. Conclusion: Acute dyspnoea caused by thyroid disease is uncommon. Nevertheless, it is the main symptom in PTL due to rapid growth and compression of the airways. Chemotherapy should be started promptly

The physical properties and evolution of Lyalpha emitting galaxies

A significant fraction of high redshift starburst galaxies presents strong Ly alpha emission. Understanding the nature of these galaxies is important to assess the role they played in the early Universe and to shed light on the relation between the narrow band selected Lyalpha emitters and the Lyman break galaxies: are the Lyalpha emitters a subset of the general LBG population? or do they represent the youngest galaxies in their early phases of formation? We studied a sample of UV continuum selected galaxies from z~2.5 to z~6 (U, B, V and i-dropouts) from the GOODS-South survey, that have been observed spectroscopically. Using the GOODS-MUSIC catalog we investigated their physical properties, such as total masses, ages, SFRs, extinction etc as determined from a spectrophotometric fit to the multi-wavelength (U band to mid-IR) SEDs, and their dependence on the emission line characteristics. In particular we determined the nature of the LBGs with Lyalpha in emission and compared them to the properties of narrow band selected Lyalpha emitters. For U and B-dropouts we also compared the properties of LBGs with and without the Lyalpha emission line.Comment: 7 pages, proceedings of the conference "Probing Stellar Populations out to the Distant Universe", Cefalu (Italy), September 7 - 19, 2008. To be published in the AIP Conf. Proc. Serie

Uncertainties and Systematic Effects on the estimate of stellar masses in high z galaxies

We discuss the uncertainties and the systematic effects that exist in the estimates of the stellar masses of high redshift galaxies, using broad band photometry, and how they affect the deduced galaxy stellar mass function. We use at this purpose the latest version of the GOODS-MUSIC catalog. In particular, we discuss the impact of different synthetic models, of the assumed initial mass function and of the selection band. Using Charlot & Bruzual 2007 and Maraston 2005 models we find masses lower than those obtained from Bruzual & Charlot 2003 models. In addition, we find a slight trend as a function of the mass itself comparing these two mass determinations with that from Bruzual & Charlot 2003 models. As consequence, the derived galaxy stellar mass functions show diverse shapes, and their slope depends on the assumed models. Despite these differences, the overall results and scenario remains unchanged. The masses obtained with the assumption of the Chabrier initial mass function are in average 0.24 dex lower than those from the Salpeter assumption, at all redshifts, causing a shift of galaxy stellar mass function of the same amount. Finally, using a 4.5 um-selected sample instead of a Ks-selected one, we add a new population of highly absorbed, dusty galaxies at z\simeq 2-3 of relatively low masses, yielding stronger constraints on the slope of the galaxy stellar mass function at lower masses.Comment: 5 pages, 4 figures, proceedings of the conference "Probing Stellar Populations out to the Distant Universe", Cefalu (Italy), September 7 - 19, 2008. To be published in the AIP Conf. Proc. Serie

Weight loss is associated with improvements in cognitive function among overweight and obese people: a systematic review and meta-analysis

Whilst obesity is associated with a higher risk of cognitive impairment, the influence of weight loss on cognitive function in obese/overweight people is equivocal. We conducted a meta-analysis of randomized controlled trials (RCTs) and longitudinal studies evaluating the influence of voluntary weight loss on cognitive function in obese/overweight individuals. Articles were acquired from a systematic search of major databases from inception till 01/2016. A random effect meta-analysis of weight loss interventions (diet, physical activity, bariatric surgery) on different cognitive domains (memory, attention, executive functions, language and motor speed) was conducted. Twenty studies (13 longitudinal studies = 551 participants; 7 RCTs = 328 treated vs. 140 controls) were included. Weight loss was associated with a significant improvement in attention and memory in both longitudinal studies and RCTs, whereas executive function and language improved in longitudinal and RCT studies, respectively. In conclusion, intentional weight loss in obese/overweight people is associated with improvements in performance across various cognitive domains. Future adequately powered RCTs are required to confirm/refute these findings

Risk of cardiovascular disease morbidity and mortality in frail and pre-frail older adults : Results from a meta-analysis and exploratory meta-regression analysis

Frailty is common and associated with poorer outcomes in the elderly, but its role as potential cardiovascular disease (CVD) risk factor requires clarification. We thus aimed to meta-analytically evaluate the evidence of frailty and pre-frailty as risk factors for CVD. Two reviewers selected all studies comparing data about CVD prevalence or incidence rates between frail/pre-frail vs. robust. The association between frailty status and CVD in cross-sectional studies was explored by calculating and pooling crude and adjusted odds ratios (ORs)+/- 95% confidence intervals (CIs); the data from longitudinal studies were pooled using the adjusted hazard ratios (HRs). Eighteen cohorts with a total of 31,343 participants were meta-analyzed. Using estimates from 10 cross-sectional cohorts, both frailty and pre-frailty were associated with higher odds of CVD than robust participants. Longitudinal data were obtained from 6 prospective cohort studies. After a median follow-up of 4.4 years, we identified an increased risk for faster onset of any type CVD in the frail (HR= 1.70 [95%CI, 1.18-2.45]; I-2 = 66%) and pre-frail (HR= 1.23 [95%CI, 1.07-1.36]; I-2 = 67%) vs. robust groups. Similar results were apparent for time to CVD mortality in the frail and pre-frail groups. In conclusion, frailty and pre-frailty constitute addressable and independent risk factors for CVD in older adults. (C) 2017 Elsevier B.V. All rights reserved.Peer reviewe