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In this paper, a model order reduction strategy is adopted for the static and dynamic behaviour simulation of a high-speed tracked vehicle. The total number of degree of freedom of the structure is condensed through a selection of interface degrees of freedom and significant global mode shapes, for an approximated description of vehicle dynamic behaviour. The methodology is implemented in a customised open-source software to reduce the computational efforts. The modelled tracked vehicle includes the sprung mass, the unsprung masses, connected by means of torsional bars, and all the track assemblies, composing the track chain. The proposed research activity presents a comprehensive investigation of the influence of the track chain, combined with longitudinal vehicle speed, on statics and vehicle dynamics, focusing on vertical dynamics. The vehicle response has been investigated both in frequency and time domain. In this last case road-wheel displacements are assumed as inputs for the model, under different working conditions, hence considering several road profiles with different amplitudes and characteristic excitation frequencies. Simulation results have proven a high fidelity in model order reduction approach and a significant contribution of the track chain in the global dynamic behaviour of the tracked vehicle.

In recent decades, the automotive industry has moved towards the development of advanced driver assistance systems to enhance the comfort, safety, and energy saving of road vehicles. The increasing connection and communication between vehicles (V2V) and infrastructure (V2I) enables further opportunities for their optimisation and allows for additional features. Among others, vehicle platooning is the coordinated control of a set of vehicles moving at a short distance, one behind the other, to minimise aerodynamic losses, and it represents a viable solution to reduce the energy consumption of freight transport. To achieve this aim, a new generation of adaptive cruise control is required, namely, cooperative adaptive cruise control (CACC). The present work aims to compare two CACC controllers applied to a platoon of heavy-duty electric trucks sharing the same linear spacing policy. A control technique based on reinforcement learning (RL) algorithm, with a deep deterministic policy gradient, and a classic linear quadratic control (LQC) are investigated. The comparative analysis of the two controllers evaluates the ability to track inter-vehicle distance and vehicle speed references during a standard driving cycle, the string stability, and the transient response when an unexpected obstacle occurs. Several performance indices (i.e., acceleration and jerk, battery state of charge, and energy consumption) are introduced as metrics to highlight the differences. By appropriately selecting the reward function of the RL algorithm, the analysed controllers achieve similar goals in terms of platoon dynamics, energy consumption, and string stability.

This paper aims at investigating powertrain behaviour, especially in transient dynamic responses, using a nonlinear truck vehicle dynamic model with a parallel hybrid configuration. A power split control was designed to achieve the desired drivability performance, with a focus on NOx emissions. The controller was characterized by high-level model-based logic used to elaborate the total powertrain torque required, and a low-level allocation strategy for splitting power between the engine and the electric motor. The final task was to enhance vehicle drivability based on driver requests, with the goal of reducing—in a hybrid configuration—transient diesel engine emissions when compared to a conventional pure thermal engine powertrain. Different parameters were investigated for the assessment of powertrain performance, in terms of external input disturbance rejection and NOx emissions reduction. The investigation of torque allocation performance was limited to the simulation of a Tip-in manoeuvre, which showed a satisfying trade-off between vehicle drivability and transient emissions.

All-cause mortality related to the SARS-CoV-2 infection has declined from the first wave to subsequent waves, probably through vaccination programs and the availability of effective antiviral therapies. Our study aimed to evaluate the impact of the SARS-CoV-2 vaccination on the prognosis of infected patients. Overall, we enrolled 545 subjects during the Delta variant wave and 276 ones during the Omicron variant wave. Data were collected concerning vaccination status, clinical parameters, comorbidities, lung involvement, laboratory parameters, and pharmacological treatment. Outcomes were admission to the intensive care unit (ICU) and 30-day all-cause mortality. Overall, the final sample included 821 patients with a mean age of 62 ± 18 years [range 18–100], and 59% were men. Vaccinated patients during the Delta wave were 37% (over ¾ with two doses), while during the Omicron wave they were 57%. Vaccinated patients were older (68 vs. 57 years), and 62% had at least one comorbidity Admission to the ICU was 20%, and the mortality rate at 30 days was 14%. ICU admissions were significantly higher during the Delta wave than during Omicron (OR 1.9, 95% CI 1.2–3.1), while all-cause mortality did not differ. Unvaccinated patients had a higher risk of ICU admission (OR 2.0, 95% CI 1.3–3.1) and 30-day all-cause mortality (OR 1.7, 95% CI 1.3–2.7). Results were consistent for both Delta and Omicron variants. Overall, vaccination with at least two doses was associated with a reduced need for ICU admission. Even one shot of the vaccine was associated with a significantly reduced 30-day mortality.

Based on observations of the behaviour of the optimal solution to the problem of energy management for plug-in hybrid electric vehicles, a novel real-time Energy Management Strategy (EMS) is proposed. In particular, dynamic programming results are used to derive a set of rules aiming at reproducing the optimal gearshift schedule in electric mode while the Adaptive Equivalent Consumption Minimization Strategy (A-ECMS) is employed to decide the powertrain operating mode and the current gear when power from the internal combustion engine is needed. In terms of total fuel consumption, simulations show that the proposed approach yields results that are close to the optimal solution and also outperforms those of the A-ECMS, a well-known EMS. One of the main aspects that differentiates the strategy here proposed from previous works is the introduction of a model to use physical considerations to estimate the energy consumption during gearshifts in dual-clutch transmissions. This, together with a series of properly tuned fuel penalties allows the controller to yield results in which there is no gear hunting behaviour.

Rollover detection and prevention are among the most critical aspects affecting the stability and safety assessment of heavy vehicles, especially for off-road driving applications. This topic has been studied in the past and analyzed in depth in terms of vehicle modelling and control algorithms design able to prevent the rollover risk. However, it still represents a serious problem for automotive carmakers due to the huge counts among the main causes for traffic accidents. The risk also becomes more challenging to predict for off-road heavy vehicles, for which the incipient rollover might be triggered by external factors, i.e., road irregularities, bank angles as well as by aggressive input from the driver. The recent advances in road profile measurement and estimation systems make road-preview-based algorithms a viable solution for the rollover detection. This paper describes a model-based formulation to analytically evaluate the load transfer dynamics and its variation due to the presence of road perturbations, i.e., road bank angle and irregularities. An algorithm to detect and predict the rollover risk for heavy vehicles is also presented, even in presence of irregular road profiles, with the calculation of the ISO-LTR Predictive Time through the Phase-Plane analysis. Furthermore, the artificial intelligence techniques, based on the recurrent neural network approach, is also presented as a preliminary solution for a realistic implementation of the methodology. The paper finally assess the efficacy of the proposed rollover predictive algorithm by providing numerical results from the simulation of the most severe maneuvers in realistic off-road driving scenarios, also demonstrating its promising predictive capabilities.

Today, few clinicians are still convinced that lipids are sepsis risk factors in patients receiving parenteral nutrition. This dogma is principally based on old literature. This review deals with the most recent literature search that provided up-to-date data over the past ten years. Systematic research was performed on Pubmed, MEDLINE, and Web of Science. The recent evidence does not justify the exclusion of lipid emulsions in patients receiving parenteral nutrition for fear of bloodstream infection risk. Moreover, lipids represent a substantial proportion of the energy source providing essential fatty acids, potentially improving clinical outcomes in patients often malnourished. Understanding the actual risk factors of sepsis during parenteral nutrition is necessary to optimize patient nutritional status and care and avoid essential fatty acid deficiency. There is an urgent need to make updated nutrition training available at all levels of medical education.

Multimode hybrid powertrains have captured the attention of automotive OEMs for their flexible nature and ability to provide better and optimized efficiency levels. However, the presence of multiple actuators, with different efficiency and dynamic characteristics, increases the problem complexity for minimizing the overall power losses in each powertrain operating condition. The paper aims at providing a methodology to select the powertrain mode and set the reference torques and angular speeds for each actuator, based on the power-weighted efficiency concept. The power-weighted efficiency is formulated to normalize the efficiency contribution from each power source and to include the inertial properties of the powertrain components as well as the vehicle motion resistance forces. The approach, valid for a wide category of multimode powertrain architectures, is then applied to the specific case of a two-mode hybrid system where the engagement of one of the two clutches enables an Input Split or Compound Split operative mode. The simulation results obtained with the procedure prove to be promising in avoiding excessive accelerations, drift of powertrain components, and in managing the power flow for uphill and downhill vehicle conditions.

Articulated tracked vehicles have been traditionally studied and appreciated for the extreme maneuverability and mobility flexibility in terms of grade and side slope capabilities. The articulation joint represents an attractive and advantageous solution, if compared to the traditional skid steering operation, by avoiding any trust adjustment between the outside and inside tracks. This paper focuses on the analysis and control of an articulated tracked vehicle characterized by two units connected through a mechanical multiaxial joint that is hydraulically actuated to allow the articulated steering operation. A realistic eight degrees of freedom mathematical model is introduced to include the main nonlinearities involved in the articulated steering behavior. A linearized vehicle model is further proposed to analytically characterize the cornering steady-state and transient behaviors for small lateral accelerations. Finally, a hitch angle controller is designed by proposing a torque-based and a speed-based Proportional Integral Derivative (PID) logics. The controller is also verified by simulating maneuvers typically adopted for handling analysis.

BACKGROUND:Previous studies showed that troponin blood levels may increase after exercise. In this study we assessed whether, among patients admitted with suspected unstable angina, the increase in high-sensitive troponin T (hs-TnT) levels after exercise stress test (EST) might help identify those with obstructive coronary artery disease (CAD) and predict symptom recurrence during short term follow-up. METHODS:Maximal treadmill EST was performed in 69 consecutive patients admitted to the emergency room with a suspicion of unstable angina (acute chest pain but confirmed normal serum levels of cardiac troponins) was measured before and 4 hours after EST. Coronary angiography was performed in 22 patients (32.8%). RESULTS:hs-TnT increased after EST compared to baseline in the whole population (from 0.84±0.65 to 1.17±0.87 ng/dL, p

Abstract Background The reversed halo, also known as the atoll sign, is a distinct sign with ring-shaped consolidation and central lucency. The reversed halo sign, initially emerging in cryptogenic organizing pneumonia, has been observed in various pulmonary diseases, including pulmonary embolism. The presence of this sign in the subpleural, posterior basal parts of the lower lobes, predominantly when solitary, should raise the possibility of other causes, such as pulmonary infarction. Case presentation We present a case of acute pulmonary embolism with pulmonary infarction discovered on a CT pulmonary angiogram in our emergency department, where the pulmonary infarction appears as a reverse halo sign with a reticulonodular pattern. The reticular nodular pattern in the halo sign is not typical of a pulmonary infarct presenting with a reverse halo sign. Conclusions To our knowledge, this is the first case of pulmonary infarction in acute pulmonary embolism with the appearance of a reverse halo sign with a reticulonodular pattern.

Abstract Background Ileocolic intussusception is a rare condition that is difficult to diagnose. A pathological lead point, usually malignant, is often the cause of adult intussusception. In emergency scenarios, radiologists must be able to identify this entity and its causes and express their opinions on associated complications. Case presentation The hospital's emergency room admitted a 75-year-old woman who was suffering from intermittent abdominal pain and constipation. An abdominal contrast-enhanced computed tomography revealed a long giant ileocolic intussusception. Considering the clinical stability and the absence of signs of complications on CT, the patient did not undergo an urgent surgical procedure but underwent a colonoscopy the following day. Surprisingly, the colonoscopy highlighted the spontaneous resolution and revealed the presence of the three tumour lead points in the cecum and ascending colon. A CT was performed after the colonoscopy, confirming the intussusception's resolution. The surgeon performed a right oncological hemicolectomy. The malignant lead points on histological examination were moderate to poorly differentiated adenocarcinomas. Conclusions A giant and long ileocolic intussusception with a long embedded visceral segment (the python colon sign) could suggest pathological lead points in the cecum and ascending colon. Despite the large size, a spontaneous resolution of the python colon is possible. In this scenario, even if, on imaging, it is impossible to macroscopically identify a lead point, in cases of giant and long ileocolic intussusceptions, every effort must be undertaken to search for the cause of the intussusception.

Abstract Background The persistently patent ductus arteriosus represents a well-known common congenital heart defect; it is uncommon in adult patients, and in any case, it debuts with atrial fibrillation. Case presentation A 75-year-old woman suffering from persistent ductus arteriosus (PDA) was admitted to the cardiology department because of atrial fibrillation, dyspnea and exercise intolerance. A PDA was detected on echocardiography and globally assessed through ECG-gated CT angiography. Conclusions Patent ductus arteriosus is an uncommon clinical finding in adulthood, and atrial fibrillation, as a consequence of chronic, progressive left atrial enlargement, may be the initial symptom. We describe the ECG-gated CT angiography imaging features of unknown patent ductus arteriosus in an elderly patient who debuted with atrial fibrillation.

This is the case of a 75-year-old man with heart failure (HF) due to severe aortic regurgitation caused by infective endocarditis treated with aortic and mitral bioprosthetic valve replacement. At 6 months, HF relapsed due to severe mitral paravalvular leak (PVL) regurgitation caused by a giant 33 mm x 9 mm crescent-shaped leak of medial-posterior location (2 to 5 o’clock position), with an area of 3.29 cm2 (figure 1A-E, video 1 of the supplementary data). The patient was deemed at prohibitive surgical risk, and gave his informed consent to undergo catheter based PVL closure. The procedure was performed in a hybrid operating room under general anesthesia, continuous real-time 2D/3D transesophageal echocardiography (TEE) color Doppler imaging and fluoroscopic guidance. An open surgical retrograde double transapical access (hybrid technique) was preferred due to the considerably huge size of the leak and the possible need for multiple simultaneous large devices. Through the 2 short sheaths placed at the left ventricle apex we easily passed the leak in sequence with 2 0.035-in hydrophilic guidewires that were later exchanged for 2 extra-stiff guidewires placed in the pulmonary veins (figure 2A-B). Afterwards, we implanted a 18 mm x 10 mm rectangular waist (RW) paravalvular leak device...

Presentamos el caso de un varón de 75 años con insuficiencia cardiaca (IC) por insuficiencia aórtica grave provocada por una endocarditis infecciosa que fue tratado con cirugía de reemplazo valvular por bioprotésicas aórtica y mitral. A los 6 meses, se confirma la recurrencia de la IC por insuficiencia mitral grave secundaria a una fuga periprotésica (FPP) causada por una fuga gigante en medialuna de 33 x 9 mm en la región posteromedial (en la posición de las 2 a las 5 en el reloj) con un área de 329 cm2 (figura 1A-E, vídeo 1 del material adicional). Se consideró al paciente de riesgo quirúrgico prohibitivo, y dio su consentimiento informado para someterse a una intervención de cierre de la FFP con catéter. La intervención se llevó a cabo en un quirófano híbrido con anestesia general, imágenes por ecocardiografía transesofágica (ETE) continua 2D/3D en tiempo real y guiado fluoroscópico. Se prefirió usar un abordaje transapical doble retrógrado quirúrgico abierto (técnica híbrida) debido al considerable tamaño de la fuga y ante la posible necesidad de usar simultáneamente múltiples dispositivos largos. Se consiguió atravesar la fuga fácilmente a través de 2 vainas cortas colocadas en el ápex del ventrículo izquierdo en una secuencia...

Abstract We investigated the cellular and molecular mechanisms by which bindarit, a small indazolic derivative with prominent anti-inflammatory effects, exerts its immunoregulatory activity in lipopolysaccharide (LPS) stimulated human monocytic cells. We found that bindarit differentially regulates the release of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1), enhancing the release of IL-8 and reducing that of MCP-1. These effects specifically required a functional interaction between bindarit and fatty acid binding protein 4 (FABP4), a lipid chaperone that couples intracellular lipid mediators to their biological targets and signaling pathways. We further demonstrated that bindarit can directly interact with FABP4 by increasing its expression and nuclear localization, thus impacting on peroxisome proliferator-activated receptor γ (PPARγ) and LPS-dependent kinase signaling. Taken together, these findings suggest a potential key-role of FABP4 in the immunomodulatory activity of bindarit, and extend the spectrum of its possible therapeutic applications to FABP4 modulation.

TRPV1 is known to be expressed in peripheral structures and the spinal cord, especially for pain processing. Here the authors show that in the brain, in particular the anterior cingulate cortex, TRPV1 is functionally expressed in microglia; stimulation of TRPV1 activates microglia, which in turn affects glutamatergic neurotransmission.

Notch signalling is a fundamental negative regulator of epidermal stemness. Here, the authors show that cell mechanics through YAP/TAZ activity prevent primary human keratinocytes from differentiating by inhibiting cell-autonomous Notch signals.