60 research outputs found
Light Commercial Vehicle ADAS-Oriented Modelling: An Optimization-Based Conversion Tool from Multibody to Real-Time Vehicle Dynamics Model
In the last few years, the number of Advanced Driver Assistance Systems (ADAS) on road vehicles has been increased with the aim of dramatically reducing road accidents. Therefore, the OEMs need to integrate and test these systems, to comply with the safety regulations. To lower the development cost, instead of experimental testing, many virtual simulation scenarios need to be tested for ADAS validation. The classic multibody vehicle approach, normally used to design and optimize vehicle dynamics performance, is not always suitable to cope with these new tasks; therefore, real-time lumped-parameter vehicle models implementation becomes more and more necessary. This paper aims at providing a methodology to convert experimentally validated light commercial vehicles (LCV) multibody models (MBM) into real-time lumped-parameter models (RTM). The proposed methodology involves the definition of the vehicle subsystems and the level of complexity required to achieve a good match between the simulation results obtained from the two models. Thus, an automatic vehicle model converter will be presented together with the assessment of its accuracy. An optimization phase is included into the conversion tool, to fine-tune uncertain vehicle parameters and to compensate for inherent modelling differences. The objective function of the optimization is based on typical performance indices used for vehicle longitudinal and lateral dynamics assessment. Finally, the simulation results from the original and converted models are compared during steady-state and transient tests, to prove the conversion fidelity
Ionic strength of the intermembrane space of intact mitochondria as estimated with fluorescein-BSA delivered by low pH fusion
The electrostatic interactions of cytochrome c with its redox partners and membrane lipids, as well as other protein interactions and biochemical reactions, may be modulated by the ionic strength of the intermembrane space of the mitochondrion. FITC-BSA was used to determine the relative value of the mitochondrial intermembrane ionic strength with respect to bulk medium external to the mitochondrial outer membrane. FITC-BSA exhibited an ionic strength-dependent fluorescence change with an affinity in the mM range as opposed to its pH sensitivity in the microM range. A controlled, low pH-induced membrane fusion procedure was developed to transfer FITC-BSA encapsulated in asolectin liposomes, to the intermembrane space of intact mitochondria. The fusion procedure did not significantly affect mitochondrial ultrastructure, electron transport, or respiratory control ratios. The extent of fusion of liposomes with the mitochondrial outer membrane was monitored by fluorescence dequenching assays using a membrane fluorescent probe (octadecylrhodamine B) and the soluble FITC-BSA fluorescent probe, which report membrane and contents mixing, respectively. Assays were consistent with a rapid, low pH-induced vesicle-outer membrane fusion and delivery of FITC-BSA into the intermembrane space. Similar affinities for the ionic strength- dependent change in fluorescence were found for bulk medium, soluble (9.8 +/- 0.8 mM) and intermembrane space-entrapped FITC-BSA (10.2 +/- 0.6 mM). FITC-BSA consistently reported an ionic strength in the intermembrane space of the functionally and structurally intact mitochondria within +/- 20% of the external bulk solution. These findings reveal that the intermembrane ionic strength changes as does the external ionic strength and suggest that cytochrome c interactions, as well as other protein interactions and biochemical reactions, proceed in the intermembrane space of mitochondria in the intact cell at physiological ionic strength, i.e., 100-150 mM
Hemorrhage during induction chemotherapy in neuroblastoma: additional risk factors in high-risk patients
Background: Neuroblastoma is the most common solid extracranial tumor in children. Patients affected by neuroblastoma are stratified into low, intermediate, and high risk in terms of event-free and overall survival. Some high-risk patients have an additional risk of acute hemorrhagic complications during induction chemotherapy. Aim: To find easily and rapidly assessed parameters that help clinicians identify those patients affected by high-risk neuroblastoma who have an additional risk of hemorrhagic complications. Methods: The clinical notes of patients diagnosed with high-risk neuroblastoma from January 2013 until February 2021 were retrospectively reviewed. Clinical, demographic and laboratory data, biological characteristics of the tumor, and information about treatment and hospital stay were identified. Results: In the examined period, 44 patients were diagnosed with high-risk neuroblastoma. Four of these patients had hemorrhagic complications within 2–7 days after the initiation of induction chemotherapy; two patients had hemothorax, one patient had hemoperitoneum and one patient had hemothorax and hemoperitoneum. The patient with isolated hemoperitoneum was treated with blood components transfusions, clotting factors and colloids infusions; the three patients with hemothorax underwent thoracostomy tube placement and respiratory support. At initial presentation, patients who suffered from hemorrhagic complications had a higher degree of hypertension (stage 2, p = 0.0003), higher levels of LDH (median 3,745 U/L, p = 0.009) and lower levels of hemoglobin (mean 7.6 gr/dl, p = 0.0007) compared to other high-risk patients. Conclusions: A subgroup of “additional” high-risk patients can be identified within the high-risk neuroblastoma patients based on mean arterial pressure, LDH levels and hemoglobin levels at presentation. Further studies to define cut-off values and optimal management strategies for these patients are needed
Los latidos del tiempo: un viaje imaginario desde el origen del universo hasta nuestros días
El conocimiento científico provisorio y cambiante, nos permite entender la realidad que nos rodea de una determinada manera. Esta no es la única forma de comprender nuestro universo pero sin duda explica los fenómenos de un modo racional y empírico. Esto se realiza mediante la formulación de hipótesis, la corroboración y contrastación de las mismas, comunicando los resultados y abriendo el juego a diversas opiniones que, lejos de criticar destructivamente, afianzan los conocimientos, solidificando las bases en una construcción colectiva del saber (Desantes-Guanter et al 2000). Este es el espíritu que se transmite a quienes participan de Latidos del Tiempo; una propuesta de extensión. Un recorrido guiado por especialistas en astronomía, zoología, ecología, biología de la conservación y antropología, que articula tres importantes centros de formación, divulgación y entretenimiento: el Observatorio Astronómico, el Museo de Ciencias Naturales y el Jardín Zoológico y Botánico de La Plata. La actividad, abarca los hitos más importantes de la evolución cósmica. Comienza con el Big Bang, incursionando por el Origen de la Vida y el Origen del Hombre hasta el presente, reflexionando sobre las problemáticas ambientales actuales y sobre nuestra responsabilidad como especie racional sobre el Planeta. El desafío y principal logro de la actividad, consiste en abordar cada tema de manera amena y multidisciplinar pero desdibujando los límites de cada disciplina, tratando de que los participantes experimenten la continuidad de los diversos hitos, integrando y relacionando los eventos, discutiendo ante distintas interpretaciones y generando nuevos interrogantes, más que de respuestas definitivas.Trabajos del área Ciencias NaturalesDepartamento de Ciencias Exactas y Naturale
Bosentan treatment for Raynauds phenomenon and skin fibrosis in patients with Systemic Sclerosis and pulmonary arterial hypertension: an open-label, observational, retrospective study.
Raynaud's phenomenon (RP) and cutaneous fibrosis are the distinctive manifestations of scleroderma, in which Endothelin-1 plays a fundamental pathogenetic role. Bosentan, an Endothelin-1 receptor antagonist used for the treatment of pulmonary arterial hypertension, retards the beginning of new sclerodermic digital ulcers (DU). This open-label, observational, retrospective study verified the effect of Bosentan on RP and skin fibrosis in sclerodermic outpatients affected by pulmonary arterial hypertension without DU. Fourteen subjects (13 women, 1 man; mean age 60 ± 7.5 years; ten with limited and four with diffuse scleroderma) were observed at baseline (T0) and after four (T1), twelve (T2), twenty-four (T3) and forty-eight (T4) weeks during treatment with Bosentan. They were evaluated for daily quantity and duration of RP attacks and skin thickness (using modified Rodnan total skin score, MRSS). Videocapillaroscopic evaluation was performed at TO and T4. Bosentan decreased significantly the number and duration of RP attacks, beginning at T2 (p<0.05). Videocapillaroscopy showed significant improvement of microcirculatory patterns at T4 (p<0.05). MRSS decreased throughout the study, reaching the statistical significance at T3 and T4 (p<0.01) in the whole cohort. The present data suggest that Bosentan is effective in stabilmng the microcirculation involvement and in improving skin fibrosis irrespective of scleroderma patterns
Sustainable development goals and 2030 agenda: Awareness, knowledge and attitudes in nine Italian universities, 2019
Sustainable Development Goals (SDGs) and 2030 Agenda represent global development programs. Education can widen the acknowledgement of their relevance and their applications. This survey aims to assess awareness, knowledge and attitudes towards SDGs and sustainability among first-year students in nine Italian Universities. A Likert scale-based online questionnaire of 70 items was compiled by students from March to July 2019. It examined knowledge and expectations referred to sustainable development concepts, indicators and documents/models accounting for sociodemographic variables. Statistical analyses performed were Chi-square test, Fisher\u2019s Exact test, Kendall\u2019s W correlation coefficient, univariate and multivariate analysis. The questionnaire was completed by 1676 students. A low percentage referred a good knowledge of SDGs and 2030 Agenda, most of them had never attended related educational activities previously. Better knowledge of SDGs and 2030 Agenda was observed in case of previous specific educational activities (p < 0.001). The expectation towards university guaranteeing an education on SDGs was high, both for personal wisdom and for usefulness in future professional context. A significant difference (p < 0.001) in such expectations was found, as healthcare students were less interested than colleagues of other areas. The results showed low knowledge but interest towards sustainable development. A scheduled implementation of academic initiatives should be considered
Modulation of the Binding of Signal Peptides to Lipid Bilayers by Dipoles near the Hydrocarbon−Water Interface †
Effect of deltorphin on behavior and hippocampal electrical activity in rabbits.
To clarify the role of delta-opioid receptors on modulation of hippocampal electrical activity and behavior, deltorphin (DT), a naturally occurring heptapeptide that selectively binds to delta-opioid receptors, was intravenously (IV) administered to rabbits. For this purpose, at 8-day intervals, the effects of IV administration of normal saline and IV infusion of synthetic DT (1 mg/kg b.wt. for 2 min) on the spontaneous behavior in neutral environment, both in absence of any external stimulus and after the introduction of a stuffed predator, were examined in seven adult male rabbits, on separate and successive occasions. During each session of experimental procedure, hippocampal EEG was also recorded by telemetry. Behavioral activity showed an increase in alert and reactive immobility after the peptide injection in comparison with that observed during control period (saline administration). Under DT treatment the frequency of hippocampal electrical activity decreased, and a reduction in rhythmicity of electrical pattern was also observed in presence of stressful stimulus. These findings show that DT may affect neural and behavioral elements related to the control of attentional and emotional processes, suggesting a modulating role of delta-opioid receptors
Role of the 12q24.12 locus in the onset of preeclampsia: an Italian case-control study
Objective: The 12q24.12 locus has been reported to be involved in the control of many traits and also in severe diseases such as cardiovascular disease, hypertension and some immune-related disease. To our knowledge, no study has been published so far investigating the role of this locus in the pathogenesis of preeclampsia (PE). Methods: We genotyped four single nucleotide polymorphisms (SNPs) in 12q24.12 locus in 198 preeclamptic, 224 chronic hypertensive and 265 normotensive women from Italy, to test the contribution polymorphisms/haplotypes on the onset of preeclampsia and their association with chronic hypertension. Results. No association was observed for any single SNP, while a common haplotype CGTG (21% in normotensive women) revealed a possible protective effect (OR 0.64, 95% CI 0.42-0.97) against preeclampsia. Conclusions: Our data suggest that a common haplotype within 12q24.12 locus may be associated with a protective effect against preeclampsia. This observation may be linked with the potential role of this region in the control of microcirculation. To the best of our knowledge, our study is the first one that links the 12q24.12 locus with this life-threatening perinatal complication of unknown etiology. Further physiological and functional studies are needed to clarify the molecular mechanisms and pathways of preeclampsi
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