57 research outputs found

    Excess-entropy scaling in supercooled binary mixtures

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    Supercooled liquids near the glass transition show remarkable non-Arrhenius transport phenomena, whose origin is yet to be clarified. Here, the authors use GPU molecular dynamics simulations for various binary mixtures in the supercooled regime to show the validity of a quasiuniversal excess-entropy scaling relation for viscosity and diffusion

    Simplified Maneuvering Strategies for Rendezvous in Near-Circular Earth Orbits

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    The development of autonomous guidance control and navigation systems for spacecraft would greatly benefit applications such as debris removals or on-orbit servicing, where human intervention is not practical. Within this context, inspired by Autonomous Vision Approach Navigation and Target Identification (AVANTI) demonstration, this work presents new guidance algorithms for rendezvous and proximity operations missions. Analytical laws are adopted and preferred over numerical methods, and mean relative orbital elements are chosen as state variables. Application times, magnitudes and directions of impulsive controls are sought to minimize propellant consumption for the planar reconfiguration of the relative motion between a passive target spacecraft and an active chaser one. In addition, simple and effective algorithms to evaluate the benefit of combining in-plane and out-of-plane maneuvers are introduced to deal with 3D problems. The proposed new strategies focus on maneuvers with a dominant change in the relative mean longitude (rarely addressed in the literature), but they can also deal with transfers where other relative orbital elements exhibit the most significant variations. A comprehensive parametric analysis compares the proposed new strategies with those employed in AVANTI and with the global optimum, numerically found for each test case. Results are similar to the AVANTI solutions when variations of the relative eccentricity vector dominate. Instead, in scenarios requiring predominant changes in the relative mean longitude, the required Delta V exhibits a 49.88% reduction (on average) when compared to the original methods. In all the test cases, the proposed solutions are within 3.5% of the global optimum in terms of Delta V. The practical accuracy of the presented guidance algorithms is also tested with numerical integration of equations of motion with J2 perturbation

    Emotions in Intercultural Relations

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    Which impact for proton pump inhibitors in SARS-CoV-2 pneumonia

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    Identification of risk factors for severe outcome of SARS-CoV-2 infection is an important issue in COVID-19 management. Much attention has been focused on comorbidities as well as drugs taken by patients. Usage of proton pump inhibitors (PPIs) appears to potentially influence disease course. These drugs are known to reduce stomach acid and also modulate the immune system. Their use, prior to and during COVID-19 infection, seems to predispose to the development of more severe pneumonia and therefore to a greater risk of mortality. Instead, the use of Histamine receptor 2 antagonists (H2RAs) seems to be associated with a better outcome in patients with COVID-19, in terms of symptoms, risk of intubation and death. As PPIs are essential for treatment of many disorders, usage of these drugs should be balanced considering the benefits and risk ratio, in order to guarantee their correct use for the necessary time. It remains to be clarified whether the detrimental effects, in terms of COVID-19 severe outcome, are due to PPIs or to the underlying disease for which they are administered. New controlled-randomized trials are required to better understand their impact in SARS-CoV-2 infections

    European symposium on precision medicine in allergy and airways diseases: report of the European Union parliament symposium (October 14, 2015)

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    On 14 October 2015, the European Academy of Allergy and Clinical Immunology (EAACI), the European Rhinologic Society (ERS) and the European Medical Association (EMA) organized a symposium in the European Parliament in Brussels on Precision Medicine in Allergy and Airways Diseases, hosted by MEP David Borrelli and with active participation of the European Respiratory So- ciety (ERS), the European Federations of Allergy and Airways Diseases Patients Associations (EFA), the Global Allergy and Asthma European Network (Ga2len), Allergic Rhinitis and Its Impact on Asthma (ARIA) and the Respiratory Effectiveness Group (REG). MEP Sirpa Pietikainen, Chair of the European Parliament Interest Group on Allergy and Asthma, underlined the importance of the need for a better diagnostic and therapeutic approach for patients with Allergies and Chronic Airways Diseases, and encouraged a joint initiative to control the epidemic of Allergy and Asthma in Europe. The socio-economic impact of allergies and chronic airways diseases cannot be underestimated, as they represent the most frequently diagnosed chronic non-communicable diseases in the EU. Despite the fact that 30% of the total European population is nowadays suffering from allergies and asthma, more than half of these patients are deprived from adequate diagnosis and treatment. Precision Medicine represents a novel approach in medicine, embracing 4 key features: personalized care based on molecular, immunologic and functional endotyping of the disease, with participation of the patient in the decision making process of therapeutic actions, and taking into account predictive and preventive aspects of the treatment. Implementation of Precision Medicine into clinical practice may help to achieve the arrest of the Epidemic of Allergies and Chronic Airways Diseases. This report summarizes the key messages delivered during the symposium by the speakers, including the EU Commissioner for Health and Food Safety Vitenys Andriukaitis. The Commissioner underscored the need for optimal patient care in Europe, supporting joint action plans for disease prevention, patient empowerment and cost-effective treatment strategies leading to a better health status of European citizens.status: publishe
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