Analysis of the Cooling Performance of a Cylindrical Hole Designed for the Suction Side of the LS89 Vane under Transitional Conditions

Thermal performance of film cooling in a transonic high-pressure vane is studied by means of two different turbulence modelling strategies: the γ-ReΘ transition model and the fully turbulent k-ω SST model. Selected test case is the LS89 vane, appropriately modified to include a cylindrical film cooling device. The MUR237 transonic configuration is selected as representative of highly loaded vanes without shocks, with transonic Mach number over the suction side. The specifically designed cooling system is based on the non-dimensional geometrical and operating conditions of the high-pressure transonic MT1 cooled vane. Transition model constants are initially tuned to match the available experimental data for the original (uncooled) configuration. Eventually, results obtained with both models are compared with each other for several jet conditions, showing non-negligible influence of turbulence modelling on flow distribution and mixing between coolant and main-flow

Why Me? To Be an Ultra-Responder to Antiplatelet Therapy: A Case Report

Background: Platelet function testing is a valid tool to investigate the clinical response to antiplatelet therapy in different clinical settings; in particular, it might supply helpful information in patients with cerebrovascular disease. Oral antiplatelet treatment, such as Aspirin (ASA) and Clopidogrel, is the gold standard in secondary stroke prevention of non-cardiogenic ischemic stroke; conversely, its application as a primary prevention therapy is not routinely recommended in patients with vascular risk factors. Multiple electrode platelet aggregometry (MEA) impedance aggregometer is a validated device to test platelet inhibition induced by ASA or Clopidogrel. Case Report: We report the case of a 78-year-old patient without relevant clinical history, taking ASA as primary prevention strategy, who was admitted for sudden onset of dysarthria and left facial hyposthenia during physical effort. Brain CT revealed two small subcortical bilateral spontaneous intracranial hemorrhages. Platelet aggregometry with MEA performed upon admission revealed a very strong platelet inhibition induced by ASA (result of the ASPI Test was 5 U, consistent with an ultra-responsiveness to ASA, and the cutoff value of correct responsiveness is <40 U). MRI at longitudinal follow-up revealed the presence of two small cavernous angioma underlying hemorrhagic spots. Conclusion: The evaluation of platelet reactivity in stroke patients undergoing antiplatelet therapies, not commonly performed in clinical practice, could be useful to optimize prevention strategies; the verification of the biological effectiveness of ASA or Clopidogrel could be a valid tool in the definition of each patient's risk profile, particularly in patients with cerebrovascular disease known to be at increased risk for both hemorrhagic and thrombotic complications

Distribution of monocarboxylate transporters in the peripheral nervous system suggests putative roles in lactate shuttling and myelination.

Lactate, a product of glycolysis, has been shown to play a key role in the metabolic support of neurons/axons in the CNS by both astrocytes and oligodendrocytes through monocarboxylate transporters (MCTs). Despite such importance in the CNS, little is known about MCT expression and lactate function in the PNS. Here we show that mouse MCT1, MCT2, and MCT4 are expressed in the PNS. While DRG neurons express MCT1, myelinating Schwann cells (SCs) coexpress MCT1 and MCT4 in a domain-specific fashion, mainly in regions of noncompact myelin. Interestingly, SC-specific downregulation of MCT1 expression in rat neuron/SC cocultures led to increased myelination, while its downregulation in neurons resulted in a decreased amount of neurofilament. Finally, pure rat SCs grown in the presence of lactate exhibited an increase in the level of expression of the main myelin regulator gene Krox20/Egr2 and the myelin gene P0. These data indicate that lactate homeostasis participates in the regulation of the SC myelination program and reveal that similar to CNS, PNS axon-glial metabolic interactions are most likely mediated by MCTs

In-hospital and out-of-hospital stroke in patients with COVID-19: two different diseases?

Background: Ischemic stroke is a known complication of COVID-19. It may have a different pathogenesis and worse outcome compared to stroke in patients without COVID-19. Furthermore, patients with COVID-19 and out-of-hospital stroke onset might have different characteristics compared to patients with COVID-19 and in-hospital stroke onset. The aim of our study was to analyze the characteristics of patients with stroke with and without COVID-19 and of patients with COVID-19 with in-hospital and out-of-hospital stroke. Methods: We performed a retrospective study of all consecutive patients admitted to our hospital with ischemic stroke between October 2020 and February 2021. We compared functional outcome, lab test, demographic, and clinical characteristics between patients with or without COVID-19. We performed a sub-analysis comparing patients with COVID-19 and in-hospital and out-of-hospital stroke onset. Results: We included in the final analysis 137 patients of whom 26 with COVID-19. Half (13) had out-of-hospital stroke and half in-hospital stroke onset. Overall, patients with COVID-19 had higher mortality compared to the control group (27% vs 9%, p: 0.02), and non-significantly lower rate of good functional outcome (50% vs 63%, p: 0.22). Patients with COVID-19 and out-of-hospital stroke had higher rate of good functional outcome (69% vs 39%, p: 0.05), higher lymphocyte count, and lower D-dimer compared with patients with in-hospital stroke onset. Conclusions: Patients with stroke and COVID-19 had higher mortality compared to patients without COVID-19. Among patients with COVID-19 those with out-of-hospital stroke had better outcome and fewer blood test abnormalities compared to patients with in-hospital stroke

Use of Telemedicine Healthcare Systems in Children and Adolescents with Chronic Disease or in Transition Stages of Life: Consensus Document of the Italian Society of Telemedicine (SIT), of the Italian Society of Preventive and Social Pediatrics (SIPPS), of the Italian Society of Pediatric Primary Care (SICuPP), of the Italian Federation of Pediatric Doctors (FIMP) and of the Syndicate of Family Pediatrician Doctors (SIMPeF)

Telemedicine is considered an excellent tool to support the daily and traditional practice of the health profession, especially when referring to the care and management of chronic patients. In a panorama in which chronic pathologies with childhood onset are constantly increasing and the improvement of treatments has allowed survival for them into adulthood, telemedicine and remote assistance are today considered effective and convenient solutions both for the chronic patient, who thus receives personalized and timely assistance, and for the doctors, who reduce the need for direct intervention, hospitalizations and consequent management costs. This Consensus document, written by the main Italian Scientific Societies involved in the use of telemedicine in pediatrics, has the objectives to propose an organizational model based on the relationships between the actors who participate in the provision of a telemedicine service aimed at minors with chronic pathologies, identifying specific project links between the areas of telemedicine in the developmental age from the first 1000 days of life to the age adult. The future scenario will have to be able to integrate digital innovation in order to offer the best care to patients and citizens. It will have to be able to provide the involvement of patients from the very beginning of the design of any care pathway, increasing where possible the proximity of the health service to citizens

Personalizing Cancer Pain Therapy: Insights from the Rational Use of Analgesics (RUA) Group

Introduction: A previous Delphi survey from the Rational Use of Analgesics (RUA) project involving Italian palliative care specialists revealed some discrepancies between current guidelines and clinical practice with a lack of consensus on items regarding the use of strong opioids in treating cancer pain. Those results represented the basis for a new Delphi study addressing a better approach to pain treatment in patients with cancer. Methods: The study consisted of a two-round multidisciplinary Delphi study. Specialists rated their agreement with a set of 17 statements using a 5-point Likert scale (0 = totally disagree and 4 = totally agree). Consensus on a statement was achieved if the median consensus score (MCS) (expressed as value at which at least 50% of participants agreed) was at least 4 and the interquartile range (IQR) was 3–4. Results: This survey included input from 186 palliative care specialists representing all Italian territory. Consensus was reached on seven statements. More than 70% of participants agreed with the use of low dose of strong opioids in moderate pain treatment and valued transdermal route as an effective option when the oral route is not available. There was strong consensus on the importance of knowing opioid pharmacokinetics for therapy personalization and on identifying immediate-release opioids as key for tailoring therapy to patients’ needs. Limited agreement was reached on items regarding breakthrough pain and the management of opioid-induced bowel dysfunction. Conclusion: These findings may assist clinicians in applying clinical evidence to routine care settings and call for a reappraisal of current pain treatment recommendations with the final aim of optimizing the clinical use of strong opioids in patients with cancer

IDENTIFICATION OF FLUCTUATION MODES FOR A CYLINDRICAL FILM COOLING HOLE USING THE SPECTRAL PROPER ORTHOGONAL DECOMPOSITION METHOD

Film cooling is the main technology adopted to guarantee safe working conditions of vanes and blades in high-pressure turbine stages. Recent experimental investigations highlighted that unsteady interaction between the coolant jet and the hot gas contributes to the lateral dispersion of cold flow over the cooled surface. Hence, considering the harsh working environment of these devices, a fair prediction of their thermal performance requires accurate modelling of the interaction between cold and hot gases. In this paper, an experimental setup originally studied at the University of Karlsruhe during the EU-funded TATEF project is numerically investigated to determine the influence of high-frequency unsteady fluctuations on the thermal performance of the cooling device. The case study consists of a film cooling hole positioned on a flat plate, working at engine-like conditions. Unsteady Reynolds-Averaged Navier-Stokes equations are solved for a compressible flow in transonic regime on a hybrid mesh. Turbulence is modelled using the Scale-Adaptive Simulation method to correctly predict the interaction between the coolant and the main flow. Three different sets of conditions are analyzed by varying the blowing ratio from 0.5 to 1.5, aiming at highlighting the unsteady mechanisms occurring for different penetrations of the coolant into the hot gas. Time-averaged unsteady results are compared with the available experimental data to determine to what extent hybrid modelling allows for correctly predicting film cooling performance at different blowing ratios. Instantaneous solutions are then analyzed to investigate the time-dependent flow field in the vicinity of the jet exit section and on the cooled surface. Spectral Proper Orthogonal Decomposition is enforced to identify the principal fluctuation modes associated with the time-dependent coolant penetration into the main flow