Advancing synthesis of decision tree-based multiple classifier systems: an approximate computing case study

AbstractSo far, multiple classifier systems have been increasingly designed to take advantage of hardware features, such as high parallelism and computational power. Indeed, compared to software implementations, hardware accelerators guarantee higher throughput and lower latency. Although the combination of multiple classifiers leads to high classification accuracy, the required area overhead makes the design of a hardware accelerator unfeasible, hindering the adoption of commercial configurable devices. For this reason, in this paper, we exploit approximate computing design paradigm to trade hardware area overhead off for classification accuracy. In particular, starting from trained DT models and employing precision-scaling technique, we explore approximate decision tree variants by means of multiple objective optimization problem, demonstrating a significant performance improvement targeting field-programmable gate array devices

Superior Vena Cava Syndrome in a Patient with Polycytemia Vera: Diagnosis and Treatment

Polycythemia vera is a myeloproliferative disorder characterized by thrombotic complications both in the arterial and venous systems. We report the case of a 55-year-old patient affected by polycythemia vera, presenting with acute superior vena cava syndrome due to thrombosis of the upper part of the superior vena cava. Diagnosis was done clinically and by computed tomography scan and showed an unusual finding: an air bubble trapped in the brachiocephalic venous trunk. The patient underwent emergency surgery. Diagnosis and treatment of the case are discussed

Functional analysis of the Bacillus subtilis cysK and cysJI genes

The function of the Bacillus subtilis cysK and cysJI (previously designated yvgQR) genes, expected to be involved in the assimilatory sulfate reduction pathway, was investigated. A B. subtilis mutant with a deletion in the cysJI genes was unable to use sulfate or sulfite as sulfur source, which confirmed that these genes encode sulfite reductase. A mutant with a transposon insertion in the cysK gene, whose deduced protein sequence showed similarity to cysteine synthases, grew poorly on sulfate and butanesulfonate. A strain in which cysK and yrhA, a cysK paralog, were inactivated was unable to grow with sulfate. Whereas expression of the cysJI genes was induced by sulfate, expression of cysK was repressed both by sulfate and by cystein

Fulminant hepatitis: a clinical review of 11 years

24 cases of fulminant hepatitis (FH) hospitalized in the Clínica de Doenças Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo during the period from January 1976 to December 1986 were reviewed from their clinical, epidemiological and laboratorial aspects. 88% of the patients died; 20 patients (83%) presented hemorrhages and, of these, 19 died. Bacterial infections occurred in 14 patients (58%) all of whom died. Ascitis was noted in 3 cases; cerebral edema was present in 16 cases. Maximal ALT levels for each patient during hospitalization ranged widely from 81 to 4,460 UI/l. Thirteen patients presented high creatinine levels (54%). Prothrombin time activity ranged from 2.1% to 67%. Fever was present in 20 cases (83%). Encephalopathy occurred within the first 2 weeks of illness in 72% of the cases. In 7 cases other illnesses were present. The etiology could not be determined in 13 cases. In 3 cases it was due to yellow fever and 6 cases were caused by viruses other than yellow fever. In one case the cause was drug usage and in another case, possibly alcohol. The authors believe that the clinical definition of FH requires further discussion before it is established. In this study FH is a young person's disease. The mortality found was similar to that by other authors. Factors that contributed to death were: hemorrhages and bacterial infection. Factors that worsened the prognosis of hepatitis were: associated illnesses and surgical procedure. The levels of ALT during hospitalization did not correlate well with the severity of the hepatitis. The authors believe that yellow fever should be considered a cause of FH where the clinical picture meets the criteria for such, although its mechanisms of encephalopathy remain obscure. The clinical details of the 3 cases of yellow fever are presented.Vinte e quatro casos de hepatite fulminante (HF), internados na Clínica de Doenças Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo durante o período de janeiro de 1976 a dezembro de 1986, foram revistos para a obtenção de dados clínicos, epidemiológicos e laboratoriais. 88% dos pacientes morreram. Vinte (83%) dos pacientes apresentaram hemorragias, dentre os quais 19 morreram (95%). Infecções bacterianas secundárias ocorreram em 14 pacientes (58%) todos os quais faleceram. Ascite foi notada em 3 casos e edema cerebral em 16 casos. Os valores máximos de ALT obtidos para cada paciente durante a internação variaram de 81 a 4.460 UI/l. Treze pacientes tiveram elevação de creatinina (54%). A atividade do tempo de protrombina variou de 2,1% a 67%. A febre esteve presente em 20 casos (83%). A encefalopatia surgiu durante as 2 primeiras semanas de doenças em 72% dos casos. Em 7 casos havia doenças associadas à hepatite. A etiologia não pode ser determinada em 13 casos; 3 casos foram por febre amarela; e 6 casos por outros vírus. Em 1 caso a causa foi drogas e em um caso, possivelmente, foi álcool. Os autores acreditam que a definição de HF merece discussão antes de ser totalmente aceita. Neste estudo, a HF foi uma doença que acometeu principalmente jovens. A letalidade encontrada foi semelhante a de outros estudos. Fatores que contribuíram para o óbito foram hemorragias e infecções bacterianas secundárias. Fatores de piora do prognóstico da hepatite foram a presença de outras doenças associadas e de procedimento cirúrgico. Os níveis de ALT durante a internação não refletiram a gravidade da hepatite. Os autores acreditam que a febre amarela deve ser considerada um agente etiológico de HF quando o seu quadro clínico seja compatível com tal, embora os mecanismos fisiopatológicos da encefalopatia sejam ainda obscuros. Os dados clínicos dos 3 casos de febre amarela são apresentados à parte

Computed tomography findings of pneumatosis and portomesenteric venous gas in acute bowel ischemia.

BACKGROUND: To use more representative sample size to evaluate whether computed tomography (CT) scan evidence of the concomitant presence of pneumatosis and portomesenteric venous gas is a predictor of transmural bowel necrosis. METHODS: Data from 208 patients who were referred for a diagnosis of bowel ischemia were retrospectively reviewed. Only patients who underwent a surgical intervention following a diagnosis of bowel ischemia who also had a post-operative histological confirmation of such a diagnosis were included. Patients were split into two groups according to the presence of histological evidence of transmural bowel ischemia (case group) or partial bowel ischemia (control group). CT images were reviewed for findings of ischemia, including mural thickening, pneumatosis, bowel distension, portomesenteric venous gas and arterial or venous thrombi. RESULTS: A total of 248 subjects who underwent surgery for bowel ischemia were identified. Among the 208 subjects enrolled in our study, transmural bowel necrosis was identified in 121 subjects (case group), and partial bowel necrosis was identified in 87 subjects (control group). Based on CT findings, including mural thickening, bowel distension, pneumatosis, pneumatosis plus portomesenteric venous gas and presence of thrombi or emboli, there were no significant differences between the case and control groups. The concomitant presence of pneumatosis and porto-mesenteric venous gas showed an odds ratio of 1.95 (95%CI: 0.491-7.775, P = 0.342) for the presence of transmural necrosis. The presence of pneumatosis plus porto-mesenteric venous gas exhibited good specificity (83%) but low sensitivity (17%) in the identification of transmural bowel infarction. Accordingly, the positive and negative predictive values were 60% and 17%, respectively. CONCLUSION: Although pneumatosis plus porto-mesenteric venous gas is associated with bowel ischemia, we have demonstrated that their co-occurrence cannot be used as diagnostic signs of transmural necrosis

Severe Kawasaki disease in a 3-month-old patient: a case report

BACKGROUND: Kawasaki disease is a multi-system vasculitis which usually occurs in children under 5 years of age. In infants under three months of age, it is very rare and usually associated with a high incidence of incomplete or atypical forms, often unresponsive to treatment. This condition increases the risk of cardiovascular complications such as coronary artery aneurysms. CASE PRESENTATION: We describe a 3-month-old infant who developed early and severe aneurysms in three coronary arteries despite a timely administration of intravenous immunoglobulins, followed by three days of intravenous methylprednisolone. CONCLUSION: This case report underlines that the development of coronary artery aneurysm correlates with a delayed diagnosis and treatment, incomplete or atypical forms of the disease, and additionally the severity of clinical presentation, especially in cases of very young infants below 3 months of age. Our case is notable because of the very young age of the patient, the severity of clinical presentation with an early development of coronary artery aneurysms and the unresponsiveness to the therapy

The ascorbic acid content of tomato fruits is associated with the expression of genes involved in pectin degradation

<p>Abstract</p> <p>Background</p> <p>High levels of ascorbic acid (AsA) in tomato fruits provide health benefits for humans and also play an important role in several aspects of plant life. Although AsA metabolism has been characterized in detail, the genetic mechanisms controlling AsA accumulation in tomatoes are poorly understood. The transcriptional control of AsA levels in fruits can be investigated by combining the advanced genetic and genomic resources currently available for tomato. A comparative transcriptomic analysis of fruit tissues was carried out on an introgression line containing a QTL promoting AsA accumulation in the fruit, using a parental cultivar with lower AsA levels as a reference.</p> <p>Results</p> <p>Introgression line IL 12-4 (<it>S. pennellii </it>in a <it>S. lycopersicum </it>background) was selected for transcriptomic analysis because it maintained differences in AsA levels compared to the parental genotypes M82 and <it>S. pennellii </it>over three consecutive trials. Comparative microarray analysis of IL 12-4 and M82 fruits over a 2-year period allowed 253 differentially-expressed genes to be identified, suggesting that AsA accumulation in IL 12-4 may be caused by a combination of increased metabolic flux and reduced utilization of AsA. In particular, the upregulation of a pectinesterase and two polygalacturonases suggests that AsA accumulation in IL12-4 fruit is mainly achieved by increasing flux through the L-galactonic acid pathway, which is driven by pectin degradation and may be triggered by ethylene.</p> <p>Conclusions</p> <p>Based on functional annotation, gene ontology classification and hierarchical clustering, a subset of the 253 differentially-expressed transcripts was used to develop a model to explain the higher AsA content in IL 12-4 fruits in terms of metabolic flux, precursor availability, demand for antioxidants, abundance of reactive oxygen species and ethylene signaling.</p

Recuperación de la información

Las Técnicas de Recuperación de Información que responden a inquietudes puntuales, se han hecho populares gracias a los buscadores ofrecidos gratuitamente a quienes recurren al Internet. Y no se hace referencia únicamente a grandes repositorios, sino también a medianos y pequeños, con miles de documentos, donde también es un inconveniente la localización del documento o los documentos que respondan a la inquietud del Usuario. El grupo posee sus propios motores orientados a corpus estáticos. De las diversas concepciones existentes ha prestado especial atención a la indexación semántica latente conocidas por sus siglas LSI. Una vez construidos los motores las líneas de investigación se han orientado a enfoques que permitan acelerar los mismos tanto en la búsqueda como en los preprocesos. Uno de ellos es el uso del procesamiento paralelo, tanto en clúster de máquinas como en el uso de placas de video. La técnica LSI es particularmente dependiente en su preproceso de un eficiente cálculo de autovalores y autovectores de matrices de gran tamaño, lo que hace incluir en nuestra temática el cálculo numérico. Se investiga si es factible acelerar la selección de los documentos que responden a un requerimiento por medio de un particionado del corpus basándose en criterios de similitud propia de minería de datos y técnicas de selección de la parte usando redes neuronales. En este sentido se exponen distintas líneas de trabajo a seguir, teniendo como objetivo diseñar, implementar y probar modificaciones en los procesos de filtrado y ordenamiento de documentos, en un Sistema de Recuperación de Información (SRI), aplicando algoritmos de clustering tradicionales.Eje: Bases de Datos y Minería de Datos.Red de Universidades con Carreras en Informátic