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Lightning-induced voltages on complex power systems by using CiLIV: The effects of channel tortuosity
No full text
Techniques for CO2 Emission Reduction over a WLTC. A Numerical Comparison of Increased Compression Ratio, Cooled EGR and Water Injection
No full textIn this work, various techniques are numerically applied to a base engine - vehicle system to estimate their potential CO2 emission reduction. The reference thermal unit is a downsized turbocharged spark-ignition Variable Valve Actuation (VVA) engine, with a Compression Ratio (CR) of 10. In order to improve its fuel consumption, preserving the original full-load torque, various technologies are considered, including an increased CR, an external low-pressure cooled EGR, and a ported Water Injection (WI). The analyses are carried out by a 1D commercial software (GT-PowerTM), enhanced by refined user-models for the description of in-cylinder processes, namely turbulence, combustion, heat transfer and knock. The latter were validated with reference to the base engine architecture in previous activities. To minimize the Brake Specific Fuel Consumption (BSFC) all over the engine operating plane, the control parameters of the base and modified engines are calibrated based on PID controllers. The calibration procedure is also verified with a direct fuel consumption minimization carried out by an external optimizer. The calibration provides the optimal Spark Advance (SA), Air-to-Fuel (A/F) ratio, Waste-Gate (WG) opening, and VVA setting, complying with limitations on knock intensity, turbine inlet temperature, boost level, turbocharger speed and in-cylinder pressure peak. The performance and calibration maps are computed for various combinations of the above technologies, including a two-stage CR system, and are compared to the ones related to the base architecture. The results show that EGR offers some BSFC benefits at low load, mainly thanks to the pumping work reduction, while it is practically ineffective for knock mitigation at high load. On the contrary, WI has the potential to substantially increase the knock resistance, improving the fuel consumption at high load. No substantial advantages are, indeed, detected with WI under knock-free operation. Computed BSFC maps are then embedded in a vehicle model with the aim of estimating the CO2 emission of a segment A vehicle over a WLTC. The proposed results give a clear outlook of the above technique potentials and offer a guideline to assess the trade-off between engine complexity and improved CO2 emission
Cytology versus histology for programmed death-ligand 1 expression evaluation in the landscape of non-small cell lung cancer patients selection for immunotherapy
No full textProgrammed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) represent key targets for specific monoclonal antibody inhibitors, such as pembrolizumab, nivolumab and atezolizumab, currently used in clinical practice for the management of metastatic non-small cell lung cancer (NSCLC) patients (1). PD-L1 expression evaluation was not required to administrate nivolumab, an anti-PD-1 inhibitor, and atezolizumab, an anti-PD-L1 inhibitor, in NSCLC second-line treatment. Conversely, pembrolizumab, an anti-PD-1 inhibitor, can be administered as single-agent, only in NSCLC patients whose sample tumours show ≥50% of PD-L1 expression, in first-line (2), or ≥1%, in second-line setting (3). More recently, the KEYNOTE-189 clinical trial demonstrated that when combined with first-line chemotherapy, pembrolizumab can be administered regardless of PD-L1 expression status (4). Thus, in non-oncogene-addicted advanced NSCLC patients, especially in first-line setting, the determination of PD-L1 expression is needed despite the possibility to use the combination of chemotherapy plus pembrolizumab. The evaluation of PD-L1 expression, in absence of head-to-head trials comparing pembrolizumab versus chemotherapy plus pembrolizumab in strong-positive PD-L1 NSCLC and in order to avoid chemotherapy administration, is still of paramount importance (2). An important consideration is that the histological sample is available only in a limited number of advanced stage NSCLC patients, in relation to sample collection difficulties (2,5). This has led to the improvement of minimal invasive procedures in collecting, directly from NSCLC central or distant lesions, cytological samples both for morphological evaluation and molecular characterization. The possibility to prepare a cytology sample as a cell block to be used in the analytical procedure validated on histological samples represent an important point to properly manage NSCLC patients. To date, the evaluation of PD-L1 expression is validated using immunohistochemistry (IHC) and in all the phase III clinical trials this analysis was performed on formalin-fixed, paraffin-embedded (FFPE) tissue specimens. Based on these considerations, the reproducibility of the survival results, showed by these trials, in the clinical practice depends also on tissue samples availability
Removable friction dampers for low-damage steel beam-to-column joints
No full textBeam-to-column joints equipped with friction dampers are promising solutions to improve the performance of
steel moment resisting frames due to the possibility to guarantee large dissipation capacity limiting the structural
damage under severe seismic conditions. In this paper, the experimental tests and the numerical simulations of
two types of joints are shown and discussed with the aim of developing pre-qualified configurations. The friction
dampers are designed to be easily removable from both the lower beam flange and the column face by means of
bolted connections. The devices are composed of a stack of steel plates conceived to assure symmetrical friction.
The friction surface is set in vertical direction in first case and in horizontal direction in the second type. The
experimental tests confirmed the effectiveness of both examined joints and the finite element analyses allowed
characterizing their local response, thus providing additional insights to improve the design requirements
Selection of tautomers in the solid state driven by metals and other inorganic components
No full textTautomers are structural isomers in ready equilibrium between each other. In the most common case of tautomerism, i. e. prototropism, tautomers differ for the position of hydrogen atoms inside the molecule and for the distribution of pi electrons.
In a certain sense, tautomers can be considered as ”living molecules”, because of the thermodynamic equilibrium they undergo. In fact, the relative amounts of the forms can be altered by physical or chemical factors, and so a tautomeric system can face a change in ambient conditions by favouring one form over the others. This responsiveness of tautomeric systems is appealing for the development of smart materials.
The dynamic equilibrium between the different tautomeric forms of a compound in solution can lead to different outcomes for the crystallization from solution: crystallization of only one tautomeric form (likely, but not necessarily, the most stable in solution), co-crystallization of different tautomers in the same lattice, concomitant formation of crystals of different tautomeric forms. Altogether, crystallization of different tautomers of the same compound is a rare occurrence and only around 0.5 % of molecules able to tautomerize and archived in the Cambridge Structural Database CSD are actually observed in different tautomeric forms in the solid state. This can be related with the fact that for many potentially tautomeric systems, the energy difference between the tautomers is high (>3 kcal/mol) and so only one form is prevailing by far in solution and found in the crystals.
In the present communication, we will provide examples of tautomeric systems for which, out of many tautomers present in solution, the selective precipitation of only one tautomer is achieved in the solid state. The selectivity can be provided by metal complexation or by formation of salts with suitable inorganic counterions
Mathematical Model for cardiac troponin T release in patients with Acute Myocardial Infarction and ST-segment Elevation
No full textCirculating biomarkers of myocardial damage represent
a cornerstone for the diagnosis and for the stratification
of patient’s risk after Acute Myocardial Infarction (AMI). The
present work presents a novel mathematical model for the
dynamic analysis of cardiac troponin T (cTnT) circulating into
the bloodstream. Tests on patients’ data show the model is
potentially useful, enabling the extraction of important clinical
information
Combination of the Searches for Pair-Produced Vectorlike Partners of the Third-Generation Quarks at root s=13 TeV with the ATLAS Detector
No full textA combination of the searches for pair-produced vectorlike partners of
the top and bottom quarks in various decay channels (T -> Zt/Wb/Ht, B ->
Zb/Wt/Hb) is performed using 36.1 fb(-1) of pp collision data at root s
= 13 TeV with the ATLAS detector at the Large Hadron Collider. The
observed data are found to be in good agreement with the standard model
background prediction in all individual searches. Therefore, combined
95\% confidence-level upper limits are set on the production cross
section for a range of vectorlike quark scenarios, significantly
improving upon the reach of the individual searches. Model-independent
limits are set assuming the vectorlike quarks decay to standard model
particles. A singlet T is excluded for masses below 1.31 TeV and a
singlet B is excluded for masses below 1.22 TeV. Assuming a weak isospin
(T, B) doublet and vertical bar V-Tb vertical bar << vertical bar V-tB
vertical bar, T and B masses below 1.37 TeV are excluded
