Il doppio esilio di Irène Némirovsky

The vicissitudes of Irène Némirovsky place us before a problem of identity, of cultural belonging, of citizenship and of exile. Imprisoned in a kind of eternal limbo, in diasporic structures that in her short life repeated themselves with amazing regularity, dragged through a series of wanderings and provisional identities, the secret key to Irène Némirovsky’s novels is scission, separation, belonging through exclusion, eternal marginality. This explains her decision, at the beginning of the war, not to flee any longer, not to face another exile. She died in Auschwitz

The cost of inaction in air pollution abatement policies

Two alternative air quality policies are compared: one is the application of only mandatory abatement measures from 2020 to 2030. The second is the definition of a more active and locally-based policy that will lead to a better air quality at the end of the decade. Using an integrated modelling system, we demonstrate that the active policy is quite more convenient from the economic viewpoint, at least for the specific situation of the Lombardy region, considered in the study. Improving particulate matter concentrations may however produce worse ozone values. A full view of all pollutants is thus necessary when planning for air quality at regional level.Copyright (c) 2022 The Authors. This is an open access article under the CC BY-NC-ND license(https://creativecommons.org/licenses/by-nc-nd/4.0/

The cost of inaction in air pollution abatement policies

Two alternative air quality policies are compared: one is the application of only mandatory abatement measures from 2020 to 2030. The second is the definition of a more active and locally-based policy that will lead to a better air quality at the end of the decade. Using an integrated modelling system, we demonstrate that the active policy is quite more convenient from the economic viewpoint, at least for the specific situation of the Lombardy region, considered in the study. Improving particulate matter concentrations may however produce worse ozone values. A full view of all pollutants is thus necessary when planning for air quality at regional level.Copyright (c) 2022 The Authors. This is an open access article under the CC BY-NC-ND license(https://creativecommons.org/licenses/by-nc-nd/4.0/

Film cooling adiabatic effectiveness measurements of pressure side trailing edge cooling configurations

Nowadays total inlet temperature of gas turbine is far above the permissible metal temperature; as a consequence, advanced cooling techniques must be applied to protect from thermal stresses, oxidation and corrosion the components located in the high pressure stages, such as the blade trailing edge. A suitable design of the cooling system for the trailing edge has to cope with geometric constraints and aerodynamic demands; state-of-the-art of cooling concepts often use film cooling on blade pressure side: the air taken from last compressor stages is ejected through discrete holes or slots to provide a cold layer between hot mainstream and the blade surface. With the goal of ensuring a satisfactory lifetime of blades, the design of efficient trailing edge film cooling schemes and, moreover, the possibility to check carefully their behavior, are hence necessary to guarantee an appropriate metal temperature distribution. For this purpose an experimental survey was carried out to investigate the film covering performance of different pressure side trailing edge cooling systems for turbine blades. The experimental test section consists of a scaled-up trailing edge model installed in an open loop suction type test rig. Measurements of adiabatic effectiveness distributions were carried out on three trailing edge cooling system configurations. The baseline geometry is composed by inclined slots separated by elongated pedestals; the second geometry shares the same cutback configuration, with an additional row of circular film cooling holes located upstream; the third model is equipped with three rows of in-line film cooling holes. Experiments have been performed at nearly ambient conditions imposing several blowing ratio values and using carbon dioxide as coolant in order to reproduce a density ratio close to the engine conditions (DR=1.52). To extend the validity of the survey a comparison between adiabatic effectiveness measurements and a prediction by correlative approach was performed to compare the experimental results with 1D methodologies

PMO Calculations for the Regiochemistry of 1,3-Cycloadditions of 3,5-Dichloro-2,4,6-trimethylbenzonitrile Oxide to Thiophen, Furan, Benzothiophen, and Benzofuran

A perturbational molecular orbital (PMO) treatment has been developed for the title 1,3-cycloaddition reactions. Molecular orbitals were computed by the CND0/2 method. The results obtained at different levels of approximation of the PMO theory are presented. The regiochemistry is also discussed on the basis of the charge transfer model by using EA\u27s and IP\u27s

Intraductal papillary mucinous neoplasia (IPMN) of the pancreas: the pivotal role of MRI for the differential diagnosis and the choice of treatment

Macrocystic pancreatic tumors seem to play an important role among neoplastic lesions of the pancreas as they sometimes either show a malignant potential or they already have neoplastic foci inside the cystic tumor. Differential diagnosis is a key factor in comparison with other cystic tumors which are not malignant as Serous Cystic Tumors (SCTs) and Mucinous Cystic Tumors (MCTs). So diagnostic imaging has become more and more important. Since May 2009 we have observed more than 200 patients with cystic lesions of the pancreas. All the patients underwent a CholangioPancreato MagneticResonance (CPMR) after an Ultrasound and/or a CT scan. Then we excluded from our study solid lesions, pseudocysts and tumors with clear signs of malignancy. CPMR was sometimes performed also using a secretine test. Finally 51 patients were evaluated and underwent a follow up programme till now. Among these patients we found 34 Intraductal Papillary Mucinous Neoplasia (IPMN), 7 MCTs and 10 SCTs. As we know that all SCTs show a lobulated septate pattern, differential diagnosis with IPMN is mandatory in order to give to the patient the treatment of choice. CPMR revealed in 32 out of 34 IPMN patients a communication between the lesion and the main pancreatic duct (MPD); so this sign, which is patognomonic of IPMN neoplasia, confirmed the diagnosis. All lesions > than 3 cm were resected by surgery (4 MCTs and 3 IPMN). Definitive histology always confirmed preoperative diagnostic imaging. Now the patients are all disease free at follow up. The other 44 patients undergo CPMR every 6 months following a “wait and see” policy. CPMR seems to be fundamental for the diagnostic screening of IPMN. This is a simple, safe and non invasive procedure which allows an early diagnosis and a better chance of cure for this kind of patients

Surfactant lung delivery with LISA and InSurE in adult rabbits with respiratory distress

Background In preterm infants, InSurE (Intubation–Surfactant–Extubation) and LISA (less invasive surfactant administration) techniques allow for exogenous surfactant administration while reducing lung injury associated with mechanical ventilation. We compared the acute pulmonary response and lung deposition of surfactant by LISA and InSurE in surfactant-depleted adult rabbits. Methods Twenty-six spontaneously breathing surfactant-depleted adult rabbits (6–7 weeks old) with moderate RDS and managed with nasal continuous positive airway pressure were randomized to 3 groups: (1) 200 mg/kg of surfactant by InSurE; (2) 200 mg/kg of surfactant by LISA; (3) no surfactant treatment (Control). Gas exchange and lung mechanics were monitored for 180 min. After that, surfactant lung deposition and distribution were evaluated monitoring disaturated-phosphatidylcholine (DSPC) and surfactant protein C (SP-C), respectively. Results No signs of recovery were found in the untreated animals. After InSurE, oxygenation improved more rapidly compared to LISA. However, at 180’ LISA and InSurE showed comparable outcomes in terms of gas exchange, ventilation parameters, and lung mechanics. Neither DSPC in the alveolar pool nor SP-C signal distributions in a frontal lung section were significantly different between InSurE and LISA groups. Conclusions In an acute setting, LISA demonstrated efficacy and surfactant lung delivery similar to that of InSurE in surfactant-depleted adult rabbits. Impact Although LISA technique is gaining popularity, there are still several questions to address. This is the first study comparing LISA and InSurE in terms of gas exchange, ventilation parameters, and lung mechanics as well as surfactant deposition and distribution. In our animal study, three hours post-treatment, LISA method seems to be as effective as InSurE and showed similar surfactant lung delivery. Our findings provide some clarifications on a fair comparison between LISA and InSurE techniques, particularly in terms of surfactant delivery. They should reassure some of the concerns raised by the clinical community on LISA adoption in neonatal units

Surfactant lung delivery with LISA and InSurE in adult rabbits with respiratory distress

Background: In preterm infants, InSurE (Intubation\u2013Surfactant\u2013Extubation) and LISA (less invasive surfactant administration) techniques allow for exogenous surfactant administration while reducing lung injury associated with mechanical ventilation. We compared the acute pulmonary response and lung deposition of surfactant by LISA and InSurE in surfactant-depleted adult rabbits. Methods: Twenty-six spontaneously breathing surfactant-depleted adult rabbits (6\u20137 weeks old) with moderate RDS and managed with nasal continuous positive airway pressure were randomized to 3 groups: (1) 200 mg/kg of surfactant by InSurE; (2) 200 mg/kg of surfactant by LISA; (3) no surfactant treatment (Control). Gas exchange and lung mechanics were monitored for 180 min. After that, surfactant lung deposition and distribution were evaluated monitoring disaturated-phosphatidylcholine (DSPC) and surfactant protein C (SP-C), respectively. Results: No signs of recovery were found in the untreated animals. After InSurE, oxygenation improved more rapidly compared to LISA. However, at 180\u2019 LISA and InSurE showed comparable outcomes in terms of gas exchange, ventilation parameters, and lung mechanics. Neither DSPC in the alveolar pool nor SP-C signal distributions in a frontal lung section were significantly different between InSurE and LISA groups. Conclusions: In an acute setting, LISA demonstrated efficacy and surfactant lung delivery similar to that of InSurE in surfactant-depleted adult rabbits. Impact: Although LISA technique is gaining popularity, there are still several questions to address. This is the first study comparing LISA and InSurE in terms of gas exchange, ventilation parameters, and lung mechanics as well as surfactant deposition and distribution.In our animal study, three hours post-treatment, LISA method seems to be as effective as InSurE and showed similar surfactant lung delivery.Our findings provide some clarifications on a fair comparison between LISA and InSurE techniques, particularly in terms of surfactant delivery. They should reassure some of the concerns raised by the clinical community on LISA adoption in neonatal units

Phase transitions in biological membranes

Native membranes of biological cells display melting transitions of their lipids at a temperature of 10-20 degrees below body temperature. Such transitions can be observed in various bacterial cells, in nerves, in cancer cells, but also in lung surfactant. It seems as if the presence of transitions slightly below physiological temperature is a generic property of most cells. They are important because they influence many physical properties of the membranes. At the transition temperature, membranes display a larger permeability that is accompanied by ion-channel-like phenomena even in the complete absence of proteins. Membranes are softer, which implies that phenomena such as endocytosis and exocytosis are facilitated. Mechanical signal propagation phenomena related to nerve pulses are strongly enhanced. The position of transitions can be affected by changes in temperature, pressure, pH and salt concentration or by the presence of anesthetics. Thus, even at physiological temperature, these transitions are of relevance. There position and thereby the physical properties of the membrane can be controlled by changes in the intensive thermodynamic variables. Here, we review some of the experimental findings and the thermodynamics that describes the control of the membrane function.Comment: 23 pages, 15 figure