Esperienze progettuali di edifici per attività natatorie

Alla città di Milano manca un centro natatorio di spicco atto ad ospitare eventi sportivi di caratura internazionale. L’articolo affronta il tema della progettazione di edifici per attività natatorie proponendo l’inquadramento di possibili soluzioni progettuali attraverso degli studi eseguiti nell’ambito del corso “Building Technology Studio” al Politecnico di Milano. I progetti sono contestualizzati nell’ambito di un quartiere originariamente pensato per il rapporto con l’acqua, ovvero Porto di Mare, sito alla periferia sud-est di Milano

Theoretical study of the thermodynamic and kinetic properties of self-interstitials in aluminum and nickel

The formation thermodynamics and migration properties of self-interstitials in aluminum and nickel are investigated as a function of temperature using atomistic simulation techniques and embedded-atom-type interatomic potentials. Molecular dynamics and nonequilibrium free-energy techniques are employed to investigate anharmonic effects on the H-O dumbbell formation properties. The equilibrium concentration of this defect is compared to those of vacancies and divacancies. The results are then analyzed in the framework of the interstitialcy model, according to which very high vibrational formation entropies should be expected for self-interstitials at high temperatures. The kinetics of self-interstitial migration is also investigated using different atomistic techniques, revealing the simultaneous activity of more than one distinct interstitial configuration as the temperature increases.731

Quantification of HIV-1 proviral DNA in patients with undetectable plasma viremia over long-term highly active antiretroviral therapy

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Atomistic simulations in the Cu-Sn system

Se presenta el procedimiento de ajuste y algunas aplicaciones de una interacción atómica para el sistema Cu-Sn bajo el esquema del Átomo Embebido Modificado (MEAM). Los potenciales para los elementos puros se extraen de la literatura. La interacción cruzada entre el Cu y el Sn reproduce aceptablemente los parámetros de red, las energías de formación y el módulo de volumen de los compuestos intermetálicos de bajas temperaturas Cu3Sn y Cu6Sn5. También se asegura su estabilidad frente a otras estructuras metaestables que compiten en energía. Las simulaciones muestran mayor movilidad del Cu al estudiar la difusividad por mecanismo de vacancias en Cu3Sn, en acuerdo a la evidencia experimentalWe present the fitting procedure and some applications of the atomic interaction for the Cu-Sn system under the Modified Embedded Atom Method (MEAM) framework. The potentials for the pure elements are extracted from the literature. The cross interaction between Cu and Sn acceptably reproduce the lattice parameters, the formation energies and bulk moduli of the low temperature intermetallic compounds Cu3Sn and Cu6Sn5. The stability against other competing metastable structures is also assured. The simulations show a greater mobility of Cu under the vacancy mechanism in Cu3Sn, in agreement with the experimental evidenceFil: Deluque Toro, Crispulo Enrique. Universidad Nacional del Comahue. Facultad de Ingeniería (UNComa-FaIn). Neuquén. ArgentinaFil: Fernández, Julián Roberto. Comisión Nacional de Energía Atómica. Gcia.Materiales, Dpto. Estruct.y Comportamiento - Universidad Nacional de General San Martín. Instituto Sábato (CNEA-UNSAM). Buenos Aires. ArgentinaFil: Ramos de Debiaggi, Susana. Universidad Nacional del Comahue. Facultad de Ingeniería (UNComa-FaIn). Neuquén. Argentin

Differences in clinical aspects of human cystic echinococcosis caused by Echinococcus granulosus sensu stricto and the G6 genotype in Neuquén, Argentina

Most human cystic echinococcosis (CE) cases worldwide are attributed to Echinococcus granulosus sensu stricto (s.s), followed by the G6 and G7 genotypes. While E. granulosus s.s. has a cosmopolitan distribution, the G6 genotype is restricted to areas where camels and goats are present. Goats are the primary livestock in the Neuquén province in Argentina where the G6 genotype has been reported to be responsible for a significant percentage of CE human cysts genotyped. In the present study, we genotyped 124 Echinococcus cysts infecting 90 CE-confirmed patients. Echinococcus granulosus s.s. was identified in 51 patients (56.7%) with 81 cysts and the G6 genotype in 39 patients (43.3%) harbouring 43 cysts. Most CE cases ≤18 years were male suggesting pastoral work could be a risk factor for the infection. Echinococcus granulosus s.s. was significantly found more frequently in the liver (32/51 patients) and the G6 genotype in the lungs and extrahepatic localizations (27/39). The patients infected with E. granulosus s.s., presented up to 6 cysts while patients infected with G6 presented a maximum of 2. The diameter of lung cysts attributed to E. granulosus s.s. was significantly larger compared to lung cysts from G6. Following the WHO ultrasound classification of liver cysts, we observed inactive cysts in 55.6% of G6 cysts and only 15.3% of E. granulosus s.s cysts. In conclusion, we provide evidence of differences in clinical aspects of CE caused by E. granulosus s.s. and the G6 genotype of E. granulosus s.l. complex infecting humans

Hydrogen bond formation in aromatic polyamine 2-Guanidinobenzimidazole : a density functional theory study

Los estudios del mecanismo de Sustitución Nucleofílica Aromática (SNAr) contribuyen a entender uno de los muchos mecanismos de reacción que tienen lugar en Química Orgánica, y poseen importantes aplicaciones en procesos como la síntesis de compuestos de “Química Fina” tales como fragancias, compuestos farmacológicos, pesticidas y también procesos industriales. Asimismo, permiten interpretar procesos naturales como la catálisis enzimática y estructuras de interés biológico. No ha sido realizado aún el estudio del mecanismo de Sustitución Nucleofílica Aromática con aminas alifáticas y aromáticas polifuncionalizadas que, debido a su rígida geometría molecular, presentan la posibilidad de formar uniones hidrógeno intramoleculares en solventes apróticos, detalle que es importante en la comprensión de las interacciones soluto-soluto y soluto-solvente a escala microscópica, y que contribuirá a elucidar el rol de las interacciones débiles no covalentes entre moléculas neutras. La poliamina aromática 2-guanidinobencimidazol puede formar unión hidrógeno intramolecular en solventes apolares apróticos, tales como tolueno, incrementando su nucleofilicidad. En este trabajo nos proponemos investigar, mediante cálculos teóricos, propiedades estructurales y electrónicas de dicha molécula y aportar datos que permitan evaluar la factibilidad de este supuesto. La búsqueda inicial de los confórmeros en equilibrio se realizó utilizando la técnica de Monte Carlo junto con el modelo autoconsistente semi-empírico AM1 (Austin Method 1) para evaluar la energía. Estas estructuras fueron luego utilizadas como punto de partida para la optimización geométrica mediante cálculos teóricos, realizados en el marco de la Teoría de la Funcional Densidad. Se utilizó el funcional híbrido B3LYP, empleando las funciones base 6-31G* y 6-31++G*Aromatic Nucleophilic Substitution (SNAr) constitutes a very important area not only from the fundamental point of view in Organic Chemistry but also from the multiple applications known in the synthesis of fine chemicals such as fragrances, pharmaceuticals, pesticides and also in industrial processes. Due to its relevance, SNAr has been subject of intensive study along the last two decades and ample progress has been achieved in what concerns to reaction mechanisms in solution. These studies also help to the interpretation of natural processes such as enzymatic catalysis and structures of biological interest. The study of the Aromatic Nucleophylic Substitution mechanism has not been made yet on polifuncionalized alyphatic and aromatic amines, which, due to their rigid molecular geometry, have the possibility of forming intramolecular hydrogen bonds in apolar aprotic solvents, an important detail in the understanding of solute-solute and solute-solvent interactions at microscopic scale, which will contribute to clarify the role of weak noncovalent interactions between neutral molecules. Aromatic polyamine 2-guanidinobenzimidazole can form intramolecular hydrogen bonds in apolar aprotic solvents, such as toluene, increasing its nucleophilicity. In this paper we investigate structural and electronic properties of this molecule and try to contribute with data to evaluate the feasibility of this assumption. The initial equilibrium conformer search was made using the Monte Carlo technique together with the self-consistent semi-empirical method AM1 (Austin Method 1) to evaluate the energy. Those structures were then used as a starting point for geometric optimization using the Functional Density Theory method. We used the hybrid functional B3LYP, and the basis functions 6-31G* and 6-31++G*Fil: Bergero, Federico Daniel. Universidad Nacional del Comahue. Facultad de Ingeniería. Departamento de Física (UNComa-FaIn). Neuquén. ArgentinaFil: Alvaro, Cecilia Elisabeth Silvana. Universidad Nacional del Comahue. Facultad de Ingeniería. Departamento de Química (UNComa-FaIn). Neuquén. ArgentinaFil: Sbarbati Nudelman, Norma. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales (UBA-FCEyN). Departamento de Química Orgánica. Buenos Aires. ArgentinaFil: Ramos de Debiaggi, Susana. Universidad Nacional del Comahue. Facultad de Ingeniería. Departamento de Física (UNComa-FaIn). Neuquén. Argentin

Antigens characterization of Echinococcus granulosus of pigs using SDS-PAGE and Western Blot

La hidatidosis, una zoonosis endémica en la Patagonia Argentina, es causada por el parásito Echinococcus granulosus sensu lato. Existen al menos 10 genotipos del parásito que originan diferencias en la especificidad de hospedador intermediario (HI), el ciclo biológico, la antigenicidad, etc. El líquido hidatídico (LH), fuente principal de antígenos para uso diagnóstico, contiene una mezcla compleja de proteínas que provienen del HI y del parásito. Los componentes principales son el antígeno (Ag) 5 y el Ag B. Se han descripto importantes diferencias en la secuencia de aminoácidos del Ag B provenientes de diferentes genotipos y HI. Los LH utilizados en las pruebas diagnósticas son generalmente de origen ovino o bovino. En la provincia de Neuquén, los porcinos (Sus scrofa) intervienen como reservorios de E. granulosus sensu lato. Sin embargo, no se han identificado los antígenos presentes en los LH de origen porcino. Los objetivos del presente trabajo fueron: 1) identificar las fracciones de proteínas de LH provenientes de porcinos de la provincia de Neuquén, durante el período 2005-2012 y 2) evaluar su antigenicidad frente a sueros de humanos con hidatidosis confirmada.Facultad de Ciencias Médica

Secondary lymphoid tissue as an important site for WU polyomavirus infection in immunocompetent children

International audienceThe polyomaviruses KI and WU (KIPyV and WUPyV) have been identified in respiratory specimens from children with acute respiratory infections, which suggests the respiratory tract as a possible site of infection. However, the persistence of infection in the lymphoid system is unknown. Fresh samples (n=211) of tonsils, adenoids, and peripheral blood mononuclear cells (PBMCs) from 83 immunocompetent children (mean age 4.8 years) were tested for amplification of the KIPyV VP1 and WUPyV VP2 genes. The known BK and JC polyomaviruses and the lymphotropic human herpesvirus HHV-6 were also investigated by quantitative real-time PCR and direct sequencing. In addition, 98 nasopharyngeal swabs collected from children (mean age 6.2 years) affected by seasonal influenza-like illness were tested. Of the lymphoid tissues, 34.9% were positive for WUPyV, 4.8% for BK virus, and 33.8% for HHV-6. KIPyV and JC virus were not detected in these specimens. None of the polyomaviruses were detected in PBMCs. Among the nasopharyngeal samples, the prevalence of WUPyV was 27.5%, although 70% of the positive samples were co-infected with at least one of the following respiratory viruses: influenza virus, adenovirus, and respiratory syncytial virus. Phylogenetic analysis revealed high sequence homology (99%) between lymphoid- and nasopharynx-derived WUPyV strains. These results suggest that the tonsils and adenoids of immunocompetent children are a reservoir for WUPyV infection; probably due to the respiratory route of transmission. In addition, the prevalence of WUPyV was high among the children, and the virus was identified more frequently in older children than during the first years of life

Genetic characterization of human hydatid cysts shows coinfection by Echinococcus canadensis G7 and Echinococcus granulosus sensu stricto G1 in Argentina

Human cystic echinococcosis caused by the larval stage of Echinococcus granulosus sensu lato (s.l.) is a highly endemic disease in the province of Neuquen, Patagonia, Argentina. Human infections with E. granulosus sensu stricto (s.s.) G1 and Echinococcus canadensis G6 were reported in Neuquen in previous studies, whereas four genotypes were identified in livestock: G1, G3, G6, and G7. The aim of this study was to identify the genotypes of E. granulosus s.l. isolates from humans of Neuquen province, Patagonia, Argentina, through the 2005–2014 period. Twenty six hydatid cysts were obtained from 21 patients. The most frequent locations were the liver and lungs. Single cysts were observed in 81.0% of patients, and combined infection of liver and lungs was detected in 9.5% of cases. Partial sequencing of mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes identified the presence of E. granulosus s.s. G1 (n = 11; 42.3%) including three different partial sequences; E. canadensis G6 (n = 14; 53.8%) and E. canadensis G7 (n = 1; 3.9%). Coinfection with G1 and G7 genotypes was detected in one patient who harbored three liver cysts. Most of the liver cysts corresponded to G1 and G6 genotypes. This study presents the first report in the Americas of a human infection with E. canadensis G7 and the second worldwide report of a coinfection with two different species and genotypes of E. granulosus s.l in humans. The molecular diversity of this parasite should be considered to redesign or improve the control program strategies in endemic regions.Centro Universitario de Estudios Microbiológicos y Parasitológico

Differences in clinical aspects of human cystic echinococcosis caused by Echinococcus granulosus sensu stricto and the G6 genotype in Neuquén, Argentina

Most human cystic echinococcosis (CE) cases worldwide are attributed to Echinococcus granulosus sensu stricto (s.s), followed by the G6 and G7 genotypes. While E. granulosus s.s. has a cosmopolitan distribution, the G6 genotype is restricted to areas where camels and goats are present. Goats are the primary livestock in the Neuquén province in Argentina where the G6 genotype has been reported to be responsible for a significant percentage of CE human cysts genotyped. In the present study, we genotyped 124 Echinococcus cysts infecting 90 CE-confirmed patients. Echinococcus granulosus s.s. was identified in 51 patients (56.7%) with 81 cysts and the G6 genotype in 39 patients (43.3%) harbouring 43 cysts. Most CE cases ≤18 years were male suggesting pastoral work could be a risk factor for the infection. Echinococcus granulosus s.s. was significantly found more frequently in the liver (32/51 patients) and the G6 genotype in the lungs and extrahepatic localizations (27/39). The patients infected with E. granulosus s.s., presented up to 6 cysts while patients infected with G6 presented a maximum of 2. The diameter of lung cysts attributed to E. granulosus s.s. was significantly larger compared to lung cysts from G6. Following the WHO ultrasound classification of liver cysts, we observed inactive cysts in 55.6% of G6 cysts and only 15.3% of E. granulosus s.s cysts. In conclusion, we provide evidence of differences in clinical aspects of CE caused by E. granulosus s.s. and the G6 genotype of E. granulosus s.l. complex infecting humans