Discrete typing units of Trypanosoma cruzi identified in rural dogs and cats in the humid Argentinean Chaco

The discrete typing units (DTUs) of Trypanosoma cruzi that infect domestic dogs and cats have rarely been studied. With this purpose we conducted a cross-sectional xenodiagnostic survey of dog and cat populations residing in 2 infested rural villages in Pampa del Indio, in the humid Argentine Chaco. Parasites were isolated by culture from 44 dogs and 12 cats with a positive xenodiagnosis. DTUs were identified from parasite culture samples using a strategy based on multiple polymerase-chain reactions. TcVI was identified in 37 of 44 dogs and in 10 of 12 cats, whereas TcV was identified in 5 dogs and in 2 cats -a new finding for cats. No mixed infections were detected. The occurrence of 2 dogs infected with TcIII -classically found in armadillos- suggests a probable link with the local sylvatic transmission cycle involving Dasypus novemcinctus armadillos and a potential risk of human infection with TcIII. Our study reinforces the importance of dogs and cats as domestic reservoir hosts and sources of various DTUs infecting humans, and suggests a link between dogs and the sylvatic transmission cycle of TcIII.Fil: Enriquez, Gustavo Fabián. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; ArgentinaFil: Cardinal, Marta Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; ArgentinaFil: Orozco, Maria Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; ArgentinaFil: Lanati, L.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; ArgentinaFil: Schijman, Alejandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Gurtler, Ricardo Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentin

LP-based Covering Games with Low Price of Anarchy

We present a new class of vertex cover and set cover games. The price of anarchy bounds match the best known constant factor approximation guarantees for the centralized optimization problems for linear and also for submodular costs -- in contrast to all previously studied covering games, where the price of anarchy cannot be bounded by a constant (e.g. [6, 7, 11, 5, 2]). In particular, we describe a vertex cover game with a price of anarchy of 2. The rules of the games capture the structure of the linear programming relaxations of the underlying optimization problems, and our bounds are established by analyzing these relaxations. Furthermore, for linear costs we exhibit linear time best response dynamics that converge to these almost optimal Nash equilibria. These dynamics mimic the classical greedy approximation algorithm of Bar-Yehuda and Even [3]

Identification of MEN1 gene mutations in families with MEN 1 and related disorders

Following identification of the MEN1 gene, we analysed patients from 12 MEN 1 families, 8 sporadic cases of MEN 1, and 13 patients with MEN 1-like symptoms (e.g. cases of familial isolated hyperparathyroidism (FIHPT), familial acromegaly, or atypical MEN 1 cases) for the presence of germline MEN1 mutations. The entire coding region of the MEN1 gene was sequenced, and mutations were detected in 11 MEN 1 families; one sporadic MEN 1 patient, one case of FIHPT and one MEN 1-like case. Constitutional DNA samples from individuals without MEN1 mutations were digested with several restriction enzymes, Southern blotted and probed with MEN1 cDNA to analyse for the presence of larger deletions of the MEN1 gene unable to be detected by PCR. One MEN 1 patient was found to carry such a deletion. This patient was heterozygous for the D418D polymorphism, however sequence analysis of RT-PCR products showed that only the variant allele was transcribed, thus confirming the result obtained by Southern analysis, which indicated loss of a region containing the initiation codon of one allele. © 2000 Cancer Research Campaig

Probabilistic Risk Assessment of Aging Layered Pressure Vessels

The National Aeronautics and Space Administration (NASA) operates approximately 300 aging layered pressure vessels that were designed and manufactured prior to ASME Boiler and Pressure Vessel (B&PV) code requirements. In order to make decisions regarding the continued fitness-for-service of these non-code carbon steel vessels, it is necessary to perform a relative risk of failure assessment for each vessel. However, risk assessment of these vessels is confounded by uncertainties and variabilities related to the use of proprietary materials in fabrication, missing construction records, geometric discontinuities, weld residual stresses, and complex service stress gradients in and around the welds. Therefore, a probabilistic framework that can capture these uncertainties and variabilities has been developed to assess the fracture risk of flaws in regions of interest, such as longitudinal and circumferential welds, using the NESSUS probabilistic modeling software and NASGRO fracture mechanics software. In this study, the probabilistic framework was used to predict variability in the stress intensity factor associated with different reference flaws located in the head-to-shell circumferential welds of a 4-layer and 14-layer pressure vessel. The probabilistic studies predict variability in flaw behavior and the important uncertain parameters for each reference flaw location

Prácticas de consumo acerca de la compra, almacenaje y preparación de aves de corral y huevos en países seleccionados del Norte y de Sur America: un estudio piloto

Antecedentes: Aves de corral, huevos, y sus productos representan un potencial peligro en la seguridad alimentaria. Prácticas de consumo relacionadas con estos alimentos han sido estudiadas en varios países, pero pocos datos existen de Latinoamérica. Objetivo: El objetivo de este estudio piloto fue proveer información de manera de caracterizar la compra, almacenaje, y preparación de aves de corral y huevos entres países: Argentina, Colombia, y Estados Unidos. Métodos: Consumidores (n=425 en total) en cada locación, completaron cuestionarios acerca del comercio de compra de aves de corral y huevos, condiciones de almacenamiento (e.j. refrigerador o freezer), preparación y prácticas de manipulación, y manipulación de sobras. Resultados: Los resultados indicaron que en Estados Unidos, la mayoría de los consumidores encuestados adquiere huevos almacenados en refrigeración, mientras que en Argentina (91%) y Colombia(84%) los huevos adquiridos estaban almacenados a temperatura ambiente. Asimismo, casi la totalidad delos consumidores en Estados Unidos almacenan los huevos en refrigeración, mientras que un 23% y un 45.9% de consumidores Argentinos y Colombianos, respectivamente almacenan huevos a temperatura ambiente, lo cual potencialmente significa una práctica no segura. Algunas prácticas sostienen posible contaminación cruzada, por ejemplo el lavado de aves y huevos previos a la cocción. Conclusiones: Los resultados muestran una primera comparación entre países de América sobre las prácticas de consumo de aves de corral y huevos, que servirán como base para futuras investigaciones y desarrollos de mensajes educacionales sobre seguridad alimentaria.Background: Poultry, eggs, and their products represent a potential food safety hazard. Although consumer practices related to these foods have been studied in various countries, little data exists from Latin America. Objective: The objective of this pilot study was to provide initial data to characterize consumers’ purchase, storage, handling, and preparation of poultry products and eggs in three countries: Argentina, Colombia, and USA. Methods: Consumers (n = 425 total) in each location completed a questionnaire about poultry products and egg purchase locations, storage conditions (i.e. refrigerator or freezer), preparation and handling practices, and managing leftovers. Results: The results indicated that in the USA most surveyed consumers purchased refrigerated eggs, whereas in Argentina (91%) and Colombia (84%) eggs typically were purchased at room temperature. Furthermore, almost all consumers in the USA stored eggs in the refrigerator, but 23% of Argentinian and 45.9% of Colombian consumers stored eggs at room temperature, which is potentially an unsafe practice. Some practices supported possible cross-contamination, for example washing raw eggs and poultry prior to cooking. Conclusions: These results are a first comparison across countries in the Americas of consumer poultry and egg practices and can serve as the basis for further research and development of food safety educational messages.Fil: Koppel, Kadri. Kansas State University; Estados UnidosFil: Sosa, Miriam Patricia. Provincia de Buenos Aires. Dirección General de Cultura y Educación. Instituto Superior Experimental de Tecnología Alimentaria. Departamento de Evaluación Sensorial de Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gutierrez Gusman, Nelson. Universidad Surcolombiana; ColombiaFil: Cardinal, Paula. Provincia de Buenos Aires. Dirección General de Cultura y Educación. Instituto Superior Experimental de Tecnología Alimentaria. Departamento de Evaluación Sensorial de Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Godwin, Sandra L.. University of Tennessee; Estados UnidosFil: Cates, Sheryl C.. No especifíca;Fil: Chambers, Edgar. Kansas State University; Estados Unido