213 research outputs found
The Durability of Composite Wood-Steel Systems
Nell\u2019ambito della valutazione e del controllo della qualit\ue0 tecnologica in edilizia, la conoscenza del comportamento nel tempo dei prodotti e componenti complessi per l\u2019edilizia, risulta aspetto fondamentale, in particolare per quei prodotti tecnologicamente \u201cinnovativi\u201d per i quali la normativa non prevede ancora prove specifiche per valutarne la durabilit\ue0.
In particolare, oggi risulta sempre pi\uf9 diffuso l\u2019impiego di sistemi assemblati o con connessioni tra materiali di diversa natura, tra cui i sistemi legno-acciaio, ottenuti rinforzando le travi in legno lamellare con piastre in acciaio forate, incollati mediante una resina epossidica bicomponente.
Tali sistemi, che sono stati gi\ue0 oggetto di sperimentazione sul comportamento a flessione del sistema trave in legno lamellare e solaio collaborante in calcestruzzo, affidano la loro efficacia in riguardo alla resistenza ed alla rigidezza attraverso gli sforzi di taglio e gli spostamenti relativi che in caso di buona collaborazione legno-acciaio sono molto ridotti.
Il presente studio si occupa di indagare la durabilit\ue0 delle caratteristiche di aderenza legno-resina-acciaio del sistema, attraverso una sperimentazione condotta su campioni secondo le procedure della normativa ISO 15686.
Dopo una prima fase di studio del sistema agenti-azioni-effetti \ue8 stato messo a punto un ciclo di invecchiamento accelerato e sono state effettuate le indagini in laboratorio in camera climatica.
Il comportamento della connessione dopo vari livelli di invecchiamento \ue8 stato analizzato attraverso prove meccaniche di resistenza al taglio, azioni cui il sistema \ue8 sottoposto in esercizio, considerando sia le sollecitazioni climatiche che possono condizionare il comportamento dei singoli componenti del sistema: resina, acciaio e legno lamellare, sia il sistema nel suo insieme per cui risulta critico il comportamento all\u2019interfaccia legno-resina e resina-acciaio.
I risultati ottenuti hanno fornito indicazioni interessanti sul comportamento del sistema nel tempo. Infatti con l\u2019avanzare dei cicli di invecchiamento si \ue8 manifestata una progressiva riduzione del carico massimo a rottura, mantenendo caratteristiche di rigidezza elevata, con spostamenti relativi ridottissimi anche sui campioni pi\uf9 invecchiati
Numerical investigation of 48 V electrification potential in terms of fuel economy and vehicle performance for a lambda-1 gasoline passenger car
Real Driving Emissions (RDE) regulations require the adoption of stoichiometric operation across the entire engine map for downsized turbocharged gasoline engines, which have been so far generally exploiting spark timing retard and mixture enrichment for knock mitigation. However, stoichiometric operation has a detrimental effect on engine and vehicle performances if no countermeasures are taken, such as alternative approaches for knock mitigation, as the exploitation of Miller cycle and/or powertrain electrification to improve vehicle acceleration performance. This research activity aims, therefore, to assess the potential of 48 V electrification and of the adoption of Miller cycle for a downsized and stoichiometric turbocharged gasoline engine. An integrated vehicle and powertrain model was developed for a reference passenger car, equipped with a EU5 gasoline turbocharged engine. Afterwards, two different 48 V electrified powertrain concepts, one featuring a Belt Starter Generator (BSG) mild-hybrid architecture, the other featuring, in addition to the BSG, a Miller cycle engine combined with an e-supercharger were developed and investigated. Vehicle performances were evaluated both in terms of elasticity maneuvers and of CO2 emissions for type approval and RDE driving cycles. Numerical simulations highlighted potential improvements up to 16% CO2 reduction on RDE driving cycle of a 48 V electrified vehicle featuring a high efficiency powertrain with respect to a EU5 engine and more than 10% of transient performance improvement
Splenomegaly impacts prognosis in essential thrombocythemia and polycythemia vera: A single center study
Splenomegaly is one of the major clinical manifestations of primary myelofibrosis and is common also in other chronic Philadelphia-negative myeloproliferative neoplasms, causing symptoms and signs and affecting quality of life of patients diagnosed with these diseases. We aimed to study the impact that such alteration has on thrombotic risk and on the survival of patients with essential thrombocythemia and patients with Polycythemia Vera (PV). We studied the relationship between splenomegaly (and its grade), thrombosis and survival in 238 patients with et and 165 patients with PV followed at our center between January 1997 and May 2019
MESENCHYMAL STEM CELLS IN PH-NEGATIVE MYELOPROLIFERATIVE NEOPLASMS: IDLE OBSERVERS OR PART OF THE DISEASE?
Aerosol and pharmacokinetic properties of denufosol support its use for early intervention in CF lung disease
Efficacy and Safety of Using High-Flow Nasal Oxygenation in Patients Undergoing Rapid Sequence Intubation.
Objective: To assess the efficacy and safety of high-flow nasal oxygen (HFNO) therapy in patients undergoing rapid sequence intubation (RSI) for emergency abdominal surgery. Methods: HFNO of 60 L.min\ue2\u88\u921at an inspiratory oxygen fraction of 1 was delivered 4 min before laryngoscopy and maintained until the patient was intubated, and correct intubation was verified by the appearance of the end-tidal CO2(EtCO2) waveform. Transcutaneous oxygenation (SpO2), heart rate and non-invasive mean arterial pressure were monitored at baseline (T0), after 4 min on HFNO (T1) and at the time of laryngoscopy (T2) and endotracheal intubation (ETI) (T3). An SpO2of <3% from baseline was recorded at any sampled time. The value of EtCO2at T3 was registered after two mechanical breaths. The apnoea time was defined as the time from the end of propofol injection to ETI. RSI was performed with propofol, fentanyl and rocuronium. Results: Forty-five patients were enrolled. SpO2levels showed a statistically significant increase at T1, T2 and T3 compared with those at T0 (p<0.05); median SpO2% (interquartile range) was 97% (range, 96%-99%) at T0, 99% (range, 99%-100%) at T1, 99% (range, 99%-100%) at T2 and 99% (range, 99%-100%) at T3. Minimal SpO2was 96%; no patient showed an SpO2of <3% from baseline; mean EtCO2at the time of ETI was 36\uc2\ub14 mmHg. Maximum apnoea time was 12 min. Conclusion: HFNO is an effective and safe technique for pre-oxygenation in patients undergoing rapid sequence induction of general anaesthesia for emergency surgery
Clinical implications of discordant early molecular responses in CML patients treated with imatinib
A reduction in BCR-ABL1/ABL1IS transcript levels to <10% after 3 months or <1% after 6 months of tyrosine kinase inhibitor therapy are associated with superior clinical outcomes in chronic myeloid leukemia (CML) patients. In this study, we investigated the reliability of multiple BCR-ABL1 thresholds in predicting treatment outcomes for 184 subjects diagnosed with CML and treated with standard-dose imatinib mesylate (IM). With a median follow-up of 61 months, patients with concordant BCR-ABL1/ABL1IS transcripts below the defined thresholds (10% at 3 months and 1% at 6 months) displayed significantly superior rates of event-free survival (86.1% vs. 26.6%) and deep molecular response (≥ MR4; 71.5% vs. 16.1%) compared to individuals with BCR-ABL1/ABL1IS levels above these defined thresholds. We then analyzed the outcomes of subjects displaying discordant molecular transcripts at 3-and 6-month time points. Among these patients, those with BCR-ABL1/ABL1IS values >10% at 3 months but <1% at 6 months fared significantly better than individuals with BCR-ABL1/ABL1IS <10% at 3 months but >1% at 6 months (event-free survival 68.2% vs. 32.7%; p < 0.001). Likewise, subjects with BCR-ABL1/ABL1IS at 3 months >10% but <1% at 6 months showed a higher cumulative incidence of MR4 compared to patients with BCR-ABL1/ABL1IS <10% at 3 months but >1% at 6 months (75% vs. 18.2%; p < 0.001). Finally, lower BCR-ABL1/GUSIS transcripts at diagnosis were associated with BCR-ABL1/ABL1IS values <1% at 6 months (p < 0.001). Our data suggest that when assessing early molecular responses to therapy, the 6-month BCR-ABL1/ABL1IS level displays a superior prognostic value compared to the 3-month measurement in patients with discordant oncogenic transcripts at these two pivotal time points
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Weight Loss and Illness Severity in Adolescents With Atypical Anorexia Nervosa.
BACKGROUND:Lower weight has historically been equated with more severe illness in anorexia nervosa (AN). Reliance on admission weight to guide clinical concern is challenged by the rise in patients with atypical anorexia nervosa (AAN) requiring hospitalization at normal weight. METHODS:We examined weight history and illness severity in 12- to 24-year-olds with AN (n = 66) and AAN (n = 50) in a randomized clinical trial, the Study of Refeeding to Optimize Inpatient Gains (www.clinicaltrials.gov; NCT02488109). Amount of weight loss was the difference between the highest historical percentage median BMI and admission; rate was the amount divided by duration (months). Unpaired t tests compared AAN and AN; multiple variable regressions examined associations between weight history variables and markers of illness severity at admission. Stepwise regression examined the explanatory value of weight and menstrual history on selected markers. RESULTS:Participants were 16.5 ± 2.6 years old, and 91% were of female sex. Groups did not differ by weight history or admission heart rate (HR). Eating Disorder Examination Questionnaire global scores were higher in AAN (mean 3.80 [SD 1.66] vs mean 3.00 [SD 1.66]; P = .02). Independent of admission weight, lower HR (β = -0.492 [confidence interval (CI) -0.883 to -0.100]; P = .01) was associated with faster loss; lower serum phosphorus was associated with a greater amount (β = -0.005 [CI -0.010 to 0.000]; P = .04) and longer duration (β = -0.011 [CI -0.017 to 0.005]; P = .001). Weight and menstrual history explained 28% of the variance in HR and 36% of the variance in serum phosphorus. CONCLUSIONS:Weight history was independently associated with markers of malnutrition in inpatients with restrictive eating disorders across a range of body weights and should be considered when assessing illness severity on hospital admission
Installation of fuel cell-based cogeneration systems in the commercial and retail sector: Assessment in the framework of the {COMSOS} project
This work studies the technical and economic feasibility of the introduction of a SOFC-based cogeneration system
to supply non-residential buildings with electricity and heat. The techno-economic evaluation is performed for
the hotel and hospital sectors, by introducing real hourly load profiles (electrical and thermal) for the buildings.
The analysis considers different countries in terms of energy intensity (and load profiles), cost of energy and
regulations/incentives. Results are achieved by comparing the SOFC scenario with a benchmark one where
electricity is supplied by the grid and heat by a natural gas fed boiler and evaluating the relative payback time
between the two solutions.
The analysis showed that, despite the current high investment cost of the SOFC system, in countries such as
Germany, Italy and UK (where electricity prices are among the highest in Europe), the option is yet advisable if
supported by effective subsidies (already existing for cogeneration systems), and it could offer a competitive
alternative to traditional systems, especially in the hospital sector, where the relative payback time is achieved in
the 10th year for UK, and in the 14th year for Germany and Italy. A cost reduction scenario has also been
analyzed: results show that the SOFC is the best option in most of the locations, both economically and in terms
of environmental impact (pollutants emissions reduction)
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