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A Benchmark of railway multibody dynamics software application to switches and crossings (S&C) is presented, comparing all major commercially available software and a few independent codes. Two different representative S&C have been implemented, using the Manchester Benchmark passenger vehicle. The final results show that all software offer a reliable and efficient way to understand the kinematic and dynamics forces between the wheels and the track elements. The highest challenges are found when modelling a combination of multiple rails in simultaneous contact with a wheel (check-stock or switch-stock), large longitudinal variations in rail shape (crossings) and high lateral steering forces (diverging cases in tight radius). In those cases, the codes able to account for the exact relative motion of each wheels with respect to each rails independently are the most apt. The most significant variations between software are found in the contact prediction with an influence on the detailed contact tangential and normal forces. The user variability is found to be very small, with the most time-consuming and error prone being the task of handling the input data for the variable rails definition. All software could benefit from improvements to assist the user and ensure higher reliability and efficiency generally.

Railway bogies of the Y25 family are the most common type of freight bogies used in Europe. However, this family of bogies presents poor curving performance and a derailment history. Although numer...

The development of detailed multibody models of railway vehicles is essential to address industrial problems through computational tools. The assessment of vehicle dynamic performance is one of the studies that can be performed with a multibody software. But when tilting trains are considered, which comprise active suspension elements, control engineering theories are required to estimate the forces developed by the actuators. Despite its importance, in general the details about the tilting control algorithm are unknown. In this work, a dedicated control design methodology is proposed to estimate the control algorithm of a tilting system in order to assure a proper vehicle performance. For this purpose, a detailed multibody model of a tilting train is used to perform a batch of simulations in order to develop an accurate linear model of the tilting system and to study its performance in realistic operation conditions. Thus, the traditional control techniques can be used to assess the tilting system dynamics and to design the control algorithm so that proper tilting performance is ensured. The control algorithm and the tilting performance are tested on a curved and tangent track with track irregularities. The comfort indexes PCT and RMS are used here to assess the tilting system.

Acute pulmonary embolism (PE) can be fatal if left untreated. Long-term prognosis of acute PE in the 21st century has not been fully reported. We aimed to determine the long-term prognosis of patients hospitalized with acute PE and compare survivalof patients with idiopathic and secondary PE.We retrospectively analysed a cohort of hospitalized patients with acute PE between 2006 and 2013.18 years, venous embolism of non-pulmonary veins, chronic thromboembolic pulmonary hypertension, and presumptive diagnosis without image confirmation. Only patients with a first PE episode were included. End-point: all-cause mortality. Patients were compared according to PE aetiology: idiopathic, secondary to neoplastic conditions and secondary to non-neoplastic conditions. A Cox-regression analysis was used to study the prognostic impact of PE aetiology.We studied 872 hospitalized acute PE patients. Median age 70 years, 56.9% were women. PE was idiopathic in 376 (43.1%), secondary to a neoplastic condition in 284 (32.6%) and secondary to a condition other than neoplasia in 212 (24.3%). Patients were followed for a median 25 months period and 508 (58.3%) died. Patients with PE attributed to a neoplastic condition had the worst survival. Patients with idiopathic PE had a multivariate-adjusted HR of mortality of 1.46 (1.08-1.99) during the over 2-year follow-up period when compared to those with acute PE attributed to a non-neoplastic condition.Patients with idiopathic acute PE have an almost 50% higher death risk in a median 2-year follow-up period than those with acute PE secondary to a condition other than neoplasia.

The development of wheel–rail contact models is an active topic of railway research with the dual objective of improving the accuracy of multibody simulations and reducing its computational effort. This paper extends the online Hertzian contact model, proposed by Pombo et al. (Veh. Syst. Dyn. 45: 165–189, 2007) to propose a non-Hertzian contact model. The new methodology presented here includes the following steps: (i) search of the points of contact; (ii) identification of the undeformed distance function; (iii) evaluation of the contact patch; (iv) calculation of the normal and tangential contact forces; (v) application of the contact forces in the multibody vehicle model. Among several contact models available in the literature, this non-Hertzian contact approach uses the Kik–Piotrowski model for the normal contact force, while the tangential forces are obtained from the interpolation of the available Kalker Book of Tables for non-Hertzian (KBTNH) contact. With the purpose to demonstrate the proper implementation and selection of parameters that define this new model, several contact analysis and dynamic simulations are performed in which the wheel S1002 and the rail UIC50 are considered. First, the contact analyses that determine the contact condition of different wheel–rail interactions serve to assess the accuracy of the Hertzian and non-Hertzian models with respect to the software of reference CONTACT. Second, the Hertzian and non-Hertzian models are utilised to perform dynamic simulations of a wheelset, a bogie and a vehicle running in tangent and curved tracks. In short, this work provides, not only a complete description of the implementation of a non-Hertzian contact model in a multibody code, but also suggests for the proper selection of the parameters that promote better accuracy and optimal computational efficiency.

The standard approach to railway vehicle dynamic analysis includes running the vehicle multibody models in rigid railway tracks. The wheel–rail contact, independently of the rolling contact model used, is either handled online or via lookup tables. This traditional approach disregards the coupling effects between the railway vehicle dynamics and the railway track flexibility. In this work the assumption of rigidity of the railway track is relaxed and a finite element model of the complete track, i.e. rails, pads, sleepers, ballast and infrastructure, is used to represent the track geometry and flexibility. A rail–wheel contact model that evaluates the contact conditions and forces is used online. The dynamics of the railway vehicle is described using a multibody methodology while the track structure is described using a finite element approach. Due to the fact that not only the multibody and the finite element dynamic analysis use different integration algorithms but also because the vehicle and track models are simulated in different, codes a co-simulation procedure is proposed and demonstrated to address the coupled dynamics of the system. This approach allows us to analyze the vehicle dynamics in a flexible track with a general geometry modeled with finite elements, i.e. including curvature, cant, vertical slopes and irregularities, which is another novel contribution. The methodology proposed in this work is demonstrated in an application, in which the railway vehicle–track interaction shows the influence of the vehicle dynamics on the track dynamics and vice versa.

Railway vehicle homologation with respect to running dynamics is addressed via dedicated norms that require the knowledge of the accelerations and wheel–rail contact forces obtained from experimental computational testing. Multibody dynamics allows the modelling of railway vehicles and their simulation on realistic operations conditions. However, the representativeness of the multibody models, and the results of their use in railway dynamics are greatly influenced by the modelling assumptions and their ability to represent the operational conditions. In this paper, two alternative multibody models of a railway vehicle are presented and simulated in a realistic railway track scenarios to appraise the consequences of different modelling assumptions on the railway dynamic analysis outcome. A vehicle–track interaction compatibility analysis is performed afterwards according to norm EN 14363. The analysis consists of two stages: the use of a simplified method, described in the norm for the identification of the different performance indexes from the railway vehicle dynamic analysis outcome; and the visual inspection of the vehicle motion with respect to the track via dedicated visualization tools. The results of the virtual vehicle homologation tests are presented and discussed in face of the modelling assumptions used, being significant differences identified between the railway vehicle modelled with cylindrical joints with clearances or with equivalent force elements. It is also concluded that the use of clearance joints prevents the need to use modelling assumptions on the equivalent force elements that have limited or no physical meaning, thus reducing the number of modelling parameters for which a high level of abstraction has to be exercised.

Background: On March 11, 2020, COVID-19 was declared a global pandemic Caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), this infection may remain asymptomatic The European Society of Medical Oncology and the Portuguese Health Authority recommended both a symptomatic survey and laboratory testing in all cancer patients (pts) undergoing immunosuppressive treatment (IT) The impact of this measure is still unknown We report our experience in a Portuguese center Methods: Since March 2020, a symptomatic survey has been performed at our institution before each hospital visit From April 6 through May 8, 2020, reverse-transcriptase polymerase chain reaction (RT-PCR) SARS-CoV-2 testing was added on cancer pts before undergoing IT The impact of this intervention was evaluated comparing the hospitalization rate of cancer pts due to COVID-19, before and after the introduction of RT-PCR testing Retrospective analysis of clinical data was performed Results: 444 tests were carried out on 244 pts and laboratory SARS-CoV-2 infection was confirmed in 11 (5%);5 were male, with a median age of 65 years [34-76] Breast and colorectal cancer were prevalent;2 pts had lung cancer;6 advanced disease Ongoing IT in these pts was temporarily suspended: 9 pts under chemotherapy, 1 atezolizumab and 1 rituximab Only 1 patient was symptomatic (9%) and previously hospitalized No admission due to COVID-19 was registered in this group Since March 7, 179 pts were admitted due to COVID-19 at our center: 12 were active cancer pts (6 7%) of which 4 were under IT 6 of the oncological pts passed away, all of them had advanced diseases, 1 was under IT Of the dead pts, lung and breast tumors were prevalent Among all COVID-19 hospitalizations, the prevalence of pts under IT was similar before and after the implementation of the RT-PCR testing (2 2% vs 2 4%) Conclusions: We found a significant percentage of active cancer pts diagnosed with asymptomatic COVID-19 Due to the small sample size of COVID-19 pts under IT, it is difficult to evaluate the impact of RT-PCR testing However, on a long-term analysis, this intervention may reduce the risk of severe complications related to COVID-19 in cancer pts Health education and dynamic organization are also important measures Legal entity responsible for the study: The authors Funding: Has not received any funding Disclosure: All authors have declared no conflicts of interest

Background The immune checkpoint inhibitors (ICI) in non-small cell lung cancer (NSCLC) had shown to increase progression-free survival (PFS) and overall survival (OS). The prognostic nutritional index (PNI) and neutrophil-to-lymphocyte ratio (NLR) are biomarkers easy to measure by blood tests and they had been studied as possible prognostic predictors in patients (pts) with various types of cancer treated with ICI. This study intends to analyze the impact of the NLR and PNI in pts with NSCLC treated with ICI. Methods Thirty-four pts with stage IV NSCLC that had started ICI in 1st and subsequent lines between 03/2016 and 06/2019 were retrospectively analyzed. The pre-treatment NLR and PNI were calculated and the cut-off 5 and 50 were respectively considered. The Kaplan-Meier method and Log Rank test and the Cox regression were used in survival analysis. Results Twenty-seven (79%) were male, with a median age of 67 (34-79) years; ECOG 0-1 (n = 30; 88%); stage IVA (n = 14; 41%); PD-L1 ≥50% (n = 18; 53%); NLR ≥5 (n = 13; 38%); PNI ≥50 (n = 14; 41%). Eleven pts (32%) were submitted to ICI in 1st line. The median follow-up time was 19,3 months (mo.). The median PFS was 6,1 mo. (95%CI 1,94-10,26) and median OS was 9,3 mo. (95%CI 0,31-18,29) - 16,5 mo. in 1st line vs 8,6 mo. in subsequent lines. The median PFS was superior in patients with PNI ≥50 (7,0 vs 2,1 mo., p = 0,039), but there weren’t differences considering the NLR. The median OS was also superior when PNI ≥50 (16,8 vs 6,7 mo., p = 0,019). In multivariate analysis (sex, age, 1st line, PD-L1, stage, ECOG, NLR and PNI), the mortality probability was superior in pts with ≥70 years [HR 6,14 (95%CI 1,49-25,39)]. Moreover, PD-L1 ≥50% [HR 0,09 (95%CI 0,01-0,52)], male sex [HR 0,03 (95%CI 0,004-0,24)], stage IVA [HR 0,26 (95%CI 0,07-0,997)] and PNI ≥50 [HR 0,15 (95%CI 0,03-0,69)] were associated to a reduced mortality risk. Conclusion PNI ≥50 was predictive of a better PFS and OS and the NLR wasnt a predictor of survival. Regarding OS, PNI ≥50 was an independent survival prognostic factor. In order to understand the impact of this biomarker in NSCLC treated with ICI, it is important to evaluate it in more studies with a larger population and prolonged follow-up time. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

The use of reliable computational tools and of validated vehicle and track models allow studying the railway vehicle performance in realistic operation conditions. The use of such advanced tools permits performing the so-called virtual homologation, which means that most of the criteria defined in the standards and regulations for vehicle acceptance can be verified numerically. This approach reduces the need of the expensive and long on-track tests, and also permits performing design optimization of several vehicle components, namely, the suspension elements, to improve its operational performance in terms of running safety, ride quality and track loading. The realism of the numerical simulations depends strongly on the model assumptions. In this work, all the mechanical elements that compose the rail vehicle are modeled properly using advanced methodologies. Then, a realistic and fully three-dimensional track, containing the measured track irregularities, is used. Finally, for a realistic running representation of the vehicle in the track, a prescribed motion of the motor wheel sets is adopted to adjust the vehicle speed as function of the track characteristics, namely, its curvature, cant angle and grade. The aim of this research is to develop a methodology to optimize the design of a rail vehicle in a mountainous track based on virtual homologation procedure. For this purpose, an optimization method is used to run the numerical simulations in batch mode and the dynamic performance of the rail vehicle is quantified based on the safety and ride quality indices defined in the standards. In addition, the optimization procedure uses a penalty term that penalizes cases where the vehicle presents an unacceptable dynamic behavior. The design variables considered are the suspension characteristics. This work provides an optimal design tool for the rail vehicle performance that leads to optimal dynamic performance in terms of running safety and ride quality.

The dynamic analysis of railway vehicles involves the independent construction of models representing vehicle, track and wheel-rail contact. In this work, a multibody formulation with Cartesian coordinates is used to describe the kinematics of the rigid bodies and joints in the vehicle model. In order to create detailed three-dimensional track finite element models, a methodology that includes the flexibility of rails and substructure is proposed. Finite element methodology is used to model the rails as beams supported in a discrete manner by spring-damper systems that represent the flexibility of pads, sleepers, ballast and substructure. The inclusion of flexible track models is very important to study the dynamic behaviour of railway vehicles in realistic operation scenarios. The proposed wheel-rail contact formulation outputs, the contact points location in real time during the dynamic analysis, for the most general three-dimensional motion of the wheelsets with respect to the track. The proposed methodology to build flexible track models is validated by comparing the results obtained with this new approach with the ones obtained using ANSYS. The methodology is demonstrated by studying the dynamic behaviour of the Alfa Pendular railway vehicle.

Hand-Schuller-Christian disease is a multifocal variant of eosinophilic granuloma, characterised by the classical triad of bony lesions, exophtamos and diabetes insipidus. This case relates recurrent Langerhan's cell histiocytisis lesions presented as destruction of periodontal support associated with diabetis in a 10-year–old patient. Medical history suggests that the case represents a case of Hand- Schuller Christian disease.

Planning of hydroelectric systems is a complex and difficult task once it involves non-linear production characteristics and depends on numerous variables. A key variable is the streamflow. Streamflow values covering the entire planning period must be accurately forecasted because they strongly influence energy production. This paper suggests an application of a FIR neural network and a fuzzy clustering-based model to evaluate one-step and multi-step ahead predictions. Results are compared to the ones obtained by a periodic autoregressive model (PAR). It is interesting to apply a recurrent neural network for prediction task due to its ability for temporal processing and efficiency to solve nonlinear problems. The results show a generally better performance of the FIR neural network for the case studied.

No presente trabalho, os autores relatam o caso de uma criança com neuroblastoma intrarenal, que foi, inicialmente, diagnosticado como tumor de Wilms. Pré-escolar, sexo feminino, com um ano e três meses, apresentava uma tumoração endurecida que ocupava o hipocôndrio esquerdo e se estendia até a região do mesogástrio, acompanhada de febre e palidez. O ultra-som do abdome total revelou massa intrarenal. A biópsia por agulha fina, em vários pontos de acesso tumoral, revelou um tumor de Wilms. Entretanto, não foi possível naquele momento realizar a imunohistoquímica (IHQ), face à escassez de material. Diante da gravidade da paciente, foi iniciado o protocolo SIOP por quatro semanas. Como não houve resposta clínica, foi indicada uma laparotomia exploradora, com ressecção parcial do tumor, sendo também, nesse momento, realizada punção aspirativa de medula óssea (MO). O exame histopatológico revelou neoplasia maligna de pequenas células mal diferenciadas. A IHQ foi negativa para WT-1 e positiva para NB-84, cromogranina e sinaptofisina. A biologia molecular revelou amplificação de N-myc. O mielograma identificou infiltração medular por pequenas células redondas. O neuroblastoma intrarenal é um tumor raro que se assemelha clínica e radiologicamente ao tumor de Wilms. Esse trabalho procura enfatizar a importância do emprego de análises imunohistoquímica e moleculares para o diagnóstico do neuroblastoma intrarenal.

We report on a 7-year-old girl with Ewing's Sarcoma (ES) who developed a poorly differentiated acute myeloid leukemia (AML-M0) 20 months after beginning the EW92 protocol for the treatment of the primary tumor. She received a total dose of 1500 mg of etoposide, a tumor cumulative radiation dose of 35Gy and granulocyte colony-stimulating factor (G-CSF) was as predicted in the protocol regimen. At onset of secondary malignancy her laboratorial analysis revealed immature blast cells characterized by CD34+/CD33-/a-MPO+ and a t(4;11)(q21;q23) abnormality. This serious complication of ES treatment, which associates etoposide, irradiation and G-CSF schedule, should be weighed against its therapeutic benefits.