A nonlinear vehicle-structure interaction methodology with wheel-rail detachment and reattachment

. A vehicle-structure interaction methodology with a nonlinear contact formulation based on contact and target elements has been developed. To solve the dynamic equations of motion, an incremental formulation has been used due to the nonlinear nature of the contact mechanics, while a procedure based on the Lagrange multiplier method imposes the contact constraint equations when contact occurs. The system of nonlinear equations is solved by an efficient block factorization solver that reorders the system matrix and isolates the nonlinear terms that belong to the contact elements or to other nonlinear elements that may be incorporated in the model. Such procedure avoids multiple unnecessary factorizations of the linear terms during each Newton iteration, making the formulation efficient and computationally attractive. A numerical example has been carried out to validate the accuracy and efficiency of the present methodology. The obtained results have shown a good agreement with the results obtained with the commercial finite element software ANSY

Middleware Fault Tolerance Support for the BOSS Embedded Operating System

Critical embedded systems need a dependable operating system and application. Despite all efforts to prevent and remove faults in system development, residual software faults usually persist. Therefore, critical systems need some sort of fault tolerance to deal with these faults and also with hardware faults at operation time. This work proposes fault-tolerant support mechanisms for the BOSS embedded operating system, based on the application of proven fault tolerance strategies by middleware control software which transparently delivers the added functionality to the application software. Special attention is taken to complexity control and resource constraints, targeting the needs of the embedded market.Fundação para a Ciência e a Tecnologia (FCT

Implementation of middleware fault tolerance support for real-time embedded applications

Critical real-time embedded systems need to apply fault tolerance strategies to deal with operation time errors, either in hardware or software. In this paper we present the ongoing work to provide application fault tolerance by means of implementing middleware transparent support over the BOSS embedded operating system. The middleware uses a publishersubscriber protocol and enables the execution of several fault tolerance strategies with minimum burden to the application level softwareFundação para a Ciência e a Tecnologia (FCT

Application-level fault tolerance in real-time embedded systems

Critical real-time embedded systems need to make use of fault tolerance techniques to cope with operation time errors, either in hardware or software. Fault tolerance is usually applied by means of redundancy and diversity. Redundant hardware implies the establishment of a distributed system executing a set of fault tolerance strategies by software, and may also employ some form of diversity, by using different variants or versions for the same processing. This work proposes and evaluates a fault tolerance framework for supporting the development of dependable applications. This framework is build upon basic operating system services and middleware communications and brings flexible and transparent support for application threads. A case study involving radar filtering is described and the framework advantages and drawbacks are discussed.Fundação para a Ciência e a Tecnologia (FCT

Applying aspects to a real-time embedded operating system

The application of aspect-oriented programming (AOP) to the embedded operating system domain is still a very controversial topic, as this area demands high performance and small memory footprint. However, recent studies quantifying aspects overheads in AspectC++ show that the resource cost is very low. Therefore, operating system development may benefit with the modularization of crosscutting concerns and system specialization offered by AOP. This paper addresses our experience in applying aspects to synchronization (mutual exclusion) and logging in a real-time embedded operating system (BOSS). Furthermore, we present our ideas for future investigation in aspect-oriented implementations for fault tolerance, middleware customization and platform variability.(undefined

Aspect-oriented fault tolerance for real-time embedded systems

Real-time embedded systems for safety-critical applications have to introduce fault tolerance mechanisms in order to cope with hardware and software errors. Fault tolerance is usually applied by means of redundancy and diversity. Redundant hardware implies the establishment of a distributed system executing a set of fault tolerance strategies by software, and may also employ some form of diversity, by using different variants or versions for the same processing. This paper describes our approach to introduce fault tolerance in distributed embedded systems applications, using aspect-oriented programming (AOP). A real-time operating system sup-porting middleware thread communication was integrated to a fault tolerant framework. The introduction of fault tolerance in the system is performed by AOP at the application thread level. The advantages of this approach include higher modularization, less efforts for legacy systems evolution and better configurability for testing and product line development. This work has been tested and evaluated successfully in several fault tolerant configurations and presented no significant performance or memory footprint costs.Fundação para a Ciência e a Tecnologia (FCT

Characterization of rust, early and late leaf spot resistance in wild and cultivated peanut germplasm

Groundnut (Arachis hypogaea) has an AB genome and is one of the most important oil crops in the world. The main constraints of crop management in Brazil are fungal diseases. Several species of the genus Arachis are resistant to pests and diseases. The objective of our experiments was to identify wild species belonging to the taxonomic section Arachis with either A or B (or " non-A" ) genomes that are resistant to early leaf spot (Cercospora arachidicola), late leaf spot (Cercosporidium personatum) and rust (Puccinia arachidis). For the identification of genotypes resistant to fungal diseases, bioassays with detached leaves were done in laboratory conditions, with artificial inoculation, a controlled temperature of 25ºC and a photoperiod of 10 h light/14 h dark, for 20-42 days, depending on the fungi species. Most of the accessions of wild species were more resistant than accessions of A. hypogaea for one, two or all three fungi species studied. Arachis monticola, considered to be a possible tetraploid ancestor or a derivative of A. hypogaea, was also more susceptible to Cercosporidium personatum and Puccinia arachidis, as compared to most of the wild species. Therefore, wild germplasm accessions of both genome types are available to be used for the introgression of resistance genes against three fungal diseases of peanut.O amendoim (Arachis hypogaea) possui genoma AB e é uma das mais importantes culturas oleaginosas em todo o mundo. Os principais problemas da cultura no Brasil são as doenças fúngicas. Várias espécies do gênero Arachis são resistentes a pragas e doenças. Este trabalho visou a identificar espécies silvestres pertencentes à seção Arachis associadas aos genomas A ou B (ou " não-A" ) do amendoim que são resistentes à mancha castanha (Cercospora arachidicola), mancha preta (Cercosporidium personatum) e ferrugem (Puccinia arachidis). Para a identificação de genótipos resistentes a doenças fúngicas, bioensaios utilizando folhas destacadas foram realizados em condições de laboratório, com inoculação artificial, temperatura controlada de 25ºC e fotoperíodo de 10h luz/14h escuro, por 20-42 dias, de acordo com a espécie fúngica. A maioria dos acessos das espécies silvestres foram mais resistentes que os acessos de A. hypogaea para uma, duas ou todas as espécies fúngicas estudadas. Arachis monticola, considerada como o possível ancestral tetraplóide ou como um derivativo de A. hypogaea, também mostrou-se mais suscetível a Cercosporidium personatum e Puccinia arachidis, quando comparado à maioria das espécies silvestres. Portanto, acessos de germoplasma silvestre com genoma A ou B estão disponíveis para serem utilizados na introgressão de genes de resistência a doenças fúngicas no amendoim

Functional results of parathyroid autotransplantation in one single pocket for treatment of secondary hyperparathyroidism

OBJETIVO: Avaliar o funcionamento e tempo cirúrgico do auto-implante de paratireóide em loja única comparando-o ao implante realizado em cinco e vinte lojas. MÉTODOS: Pacientes submetidos à parotidectomia total com auto implante (Ptx-AI) por hiperparatireoidismo secundário e terciário foram avaliados em grupos de implantes em 20 lojas (A), cinco lojas (B) e loja única (C), em relação ao Estado Funcional (EF) do implante e ao tempo cirúrgico deste. Foram determinados quatro Estados Funcionais de acordo com o nível sistêmico de PTH: 1-abaixo do normal; 2-normal; 3- elevado não mais que três vezes; 4- elevado mais que três vezes. RESULTADOS: Foram submetidos a Ptx-AI 349 pacientes, por hiperparatireoidismo renal, entre 1994 a 2009. Para o estudo funcional foram elegíveis 101 pacientes com as seguintes observações: grupo A (n=30) - EF1 16,6%, EF2 50%, EF3 23,3% e EF4 10%; grupo B (n=41) - EF1 14,6%, EF2 58,5%, EF3 22% e EF4 4,9%; Grupo C (n=30) - EF1 17%, EF2 57%, EF3 20% e EF4 6% (p=0,9, x²). Porém no grupo C, o tempo cirúrgico médio do implante foi estatisticamente mais rápida (7,9 minutos) em relação à média em cinco lojas (18,6 minutos) e 20 lojas (44 minutos), em 66 pacientes avaliados (p<0,0001, ANOVA). CONCLUSÃO: O auto-implante em loja única diminui o tempo cirúrgico sem alterar a funcionalidade do mesmo.OBJECTIVE: To evaluate the operation and surgical time of autotransplanted parathyroid in a single site comparing it to the implant performed in five and twenty locations. METHODS: Patients who underwent total parotidectomy with auto implant (Ptx-AI) for secondary and tertiary hyperparathyroidism were evaluated in groups of 20 implant sites (A), 5 sites (B) and single site (C), compared as for Functional Status (FE) of the implant and the surgical time of the procedure. Four functional states were determined according to the systemic level of PTH: 1-below normal, 2-normal, 3-high, no more than three times and 4 - more than three times higher. RESULTS: There were 349 patients subjected to Ptx-AI for renal hyperparathyroidism from 1994 to 2009. For the functional study, 101 patients were eligible for the following observations: group A (n = 30) - 16.6% EF1, 50% EF2, 23.3% EF3 and 10%EF4; group B (n = 41) - 14.6% EF1, 58.5% EF2, 22% EF3 and 4.9% EF4; Group C (n = 30) - 17% EF1, 57% EF2, 20%EF3 and 6% EF4 (p = 0.9, x²). But in group C the mean operative time of implant was statistically lower (7.9 minutes) compared to the average of 5 site (18.6 minutes) and 20-site (44 minutes) implants in 66 evaluated patients (p<0,0001, ANOVA). CONCLUSION: The self-implantation in a single site decreases the operative time without changing its functionality

Comparative study of etiological diagnosis of nosocomial pneumonia

Nosocomial pneumonia is a common complication in patients on mechanical ventilation and results in significant mortality. Diagnosis of pneumonia in patients who are intubated and under mechanical ventilation is difficult, even with the aid of clinical, laboratorial, and endoscopic tests. The objective of this study was to compare three methods of tracheal sputum collection in patients with a clinical and radiological diagnosis of pneumonia. Twenty-two patients with a clinical diagnosis of liver disease were enrolled, 18 years of age or older, 13 males and nine females, who had been mechanically ventilated over an intubation period of 5.86 &plusmn; 4.62 days. These patients were being treated in intensive care unit (ICU) of the Liver Transplantdepartment. Secretion collection was carried out according to a protocol with three distinct methods: endotracheal aspiration with a closed aspiration system, Bal cath and bronchoalveolar lavage. Of the 22 patients analyzed, 21 (95.4%) showed one or more infectious agent when the closed aspiration system was used. With the Bal cathâ collection, 19 patients (86.3%) had one or more infectious agents; in the collection by bronchoalveolar lavage, 10 patients (45.4%) presented one or more infectious agent. According to the laboratorial analysis, 14 different microorganisms were isolated, the most frequent of which were Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. We concluded that aspiration with the closed system produced the most effective results in comparison with those of bronchoalveolar lavage and the Bal cathâ, and may be an acceptable method for diagnosing hospital-acquired pneumonia when no fiberoptic technique is available

Surgical approach to medullary thyroid carcinoma associated with multiple endocrine neoplasia type 2

We briefly review the surgical approaches to medullary thyroid carcinoma associated with multiple endocrine neoplasia type 2 (medullary thyroid carcinoma/multiple endocrine neoplasia type 2). The recommended surgical approaches are usually based on the age of the affected carrier/patient, tumor staging and the specific rearranged during transfection codon mutation. We have focused mainly on young children with no apparent disease who are carrying a germline rearranged during transfection mutation. Successful management of medullary thyroid carcinoma in these cases depends on early diagnosis and treatment. Total thyroidectomy should be performed before 6 months of age in infants carrying the rearranged during transfection 918 codon mutation, by the age of 3 years in rearranged during transfection 634 mutation carriers, at 5 years of age in carriers with level 3 risk rearranged during transfection mutations, and by the age of 10 years in level 4 risk rearranged during transfection mutations. Patients with thyroid tumor >5 mm detected by ultrasound, and basal calcitonin levels >40 pg/ml, frequently have cervical and upper mediastinal lymph node metastasis. In the latter patients, total thyroidectomy should be complemented by extensive lymph node dissection. Also, we briefly review our data from a large familial medullary thyroid carcinoma genealogy harboring a germline rearranged during transfection Cys620Arg mutation. All 14 screened carriers of the rearranged during transfection Cys620Arg mutation who underwent total thyroidectomy before the age of 12 years presented persistently undetectable serum levels of calcitonin (<2 pg/ml) during the follow-up period of 2–6 years. Although it is recommended that preventive total thyroidectomy in rearranged during transfection codon 620 mutation carriers is performed before the age of 5 years, in this particular family the surgical intervention performed before the age of 12 years led to an apparent biochemical cure