Quenching of excited carbonyl triplets by benzene derivatives

Se ha medido la velocidad de desactivación de tripletes carbonilicos (biacetilo, bencilo, benzofenona y 4-metil-2-pentanona) por una serie d,e derivados del benceno. Los resultados pueden ser interpretados por un mecanismo de transferencia de carga. Los compuestos con hidrógenos lábiles (i.e.cumeno) muestran una mayor reactividad. La abstracción de hidrógeno ocurre desde el complejo de transferencia de carga. La desactivación del triplete de la 4-metil-2-pentanona fue medida entre - 5 y 70°C. Las energias de activación obtenidas variaron entre 8.1 kcal (para el cumeno) y 10 kcal (para el benceno)

Modelado y simulacion de un biofiltro para el tratamiento de gases contaminados con compuestos sulfurados

A mathematical model and the simulation of a biofilter for the treatment of gaseous effluents are presented. The mixture included sulfur compounds such as hydrogen sulfide, methyl mercaptan, dimethyl sulfide and dimethyl disulfide, all dissolved in air. The conditions under which restrictions on diffusion are of less importance than biodegradation, which is the ultimate limiting factor, were determined. The model was applied to the biofilm and the results were used to simulate the behavior of the bioreactor. The flows and maximum concentrations of contaminants in the mixture to be treated for a given size of bioreactor, were determined. Also, the concentration-related variations in the efficiency of the removal of contaminants under varying conditions of flow and concentration in the mixture, were established. It was found that biodegradation in the biofilm was the limiting factor for mixtures with concentrations of contaminants greater than 90 ppm

Type-based allocation analysis for co-recursion in lazy functional languages

This paper presents a novel type-and-effect analysis for pre-dicting upper-bounds on memory allocation costs for co-recursive def-initions in a simple lazily-evaluated functional language. We show thesoundness of this system against an instrumented variant of Launch-bury’s semantics for lazy evaluation which serves as a formal cost model.Our soundness proof requires an intermediate semantics employing indi-rections. Our proof of correspondence between these semantics that weprovide is thus a crucial part of this work.The analysis has been implemented as an automatic inference system.We demonstrate its effectiveness using several example programs thatpreviously could not be automatically analysed.Postprin

RELACIÓN ENTRE MATERIALES GEOLÓGICOS Y LAS PROPIEDADES FÍSICAS Y QUÍMICAS DE LOS SUELOS.

El presente estudio fue realizado en la zona de influencia de la cordillera del Ybytyruzu en el Departamento de Guaira, localidad ubicada al sureste de Asunción. El objetivo principal de la presente investigación fue identificar los principales efectos que producen la roca basáltica y la roca arenisca sobre las propiedades físicas y químicas de los suelos formados a partir de ellas. La metodología aplicada en este estudio consistió en trabajos de campo y análisis laboratorial de las muestras obtenidas.Los resultados indican marcada diferencia, tanto en las propiedades físicas y químicas, entre los suelos originados de rocas sedimentarias - arenisca y suelos originados de rocas ígneas - basalto. La textura gruesa es dominante para suelos originados de arenisca, mientras que la textura fina predomina en suelos originados de basalto. Utilizando el método del tacto también se identificó importantes diferencias en la plasticidad y pegajosidad de suelos originados de rocas sedimentarias – areniscas fue muy baja en relación a suelos originados de roca basáltica. La estructuración también fue más débil en suelos de textura gruesa en comparación a suelos de textura fina. En cuanto al tamaño de poros se puede mencionar que los suelos de textura gruesa, conpredominancia de arena presentan mayor cantidad de macroporos en comparación a suelos de textura fina en donde se observó mayor cantidad de microporos.En relación a los aspectos químicos, el pH en suelos originados de rocas sedimentarias presenta menor rango en relación a los suelos originados de basalto. En cuanto a la acidez intercambiable, el nivel fue mayor en suelos originados de roca sedimentaria que los suelos de textura fina. Las sumas de bases, el contenido de materia orgánica y el nivel de fósforo sin embargo presentaron rangos menores para suelos de textura gruesa en relación a los suelos de textura fina

Effect of reproductive indices and bovine somatotropin on milk yield in Holstein cows experiencing climatic sub-fertility

Cilj ovog istraživanja bio je utvrditi povezanost između reproduktivnih indeksa i ukupnog prinosa mlijeka u neplaniranim laktacijama ≥600 dana u neplodnih holstein krava liječenih ili neliječenih rekombinantnim goveđim somatotropinom (rbST) i koje su imale produljenu hipertermiju. U studiju je bilo uključeno 1141 krava s jednom laktacijom: 622 nisu liječene rbST-om (kontrola), a 519 je liječeno rbST-om (500 mg svakih 14 dana tijekom laktacije). U svim paritetima, kontrolne krave s >480 dana držanja na otvorenom dale su 5642 kg mlijeka više (p380 dana na otvorenom i nastavljaju se osjemenjivati nakon 10 neuspješnih tretmana rbST-om, učinak odgođene koncepcije nije u potpunosti negativan budući da je količina mlijeka proizvedena tijekom produžene višestruko nadmašila eventualne gubitke.This study aimed at determining the association between reproductive indexes and the total milk yield in non-planed lactations ≥600 days in sub-fertile Holstein cows treated or not with recombinant bovine somatotropin (rbST) and experienced prolonged hyperthermia. A total of 1141 cows with a single lactation were enrolled in the study: 622 were not treated with rbST (control) and 519 were treated with rbST (500 mg every 14 days throughout lactation). Across parities, control cows with >480 days open, produced 5642 kg more milk (p380 days open and they continue to be inseminated after 10 unsuccessful services, the impact of delayed conception is not entirely negative as this disadvantage is more than outweighed by the extra milk that is produced when lactation is extended

Estrategias de prevención en el paciente con deficiencia auditiva

El mayor obstáculo en la atención odontoló­gica de personas con deficiencias auditivas se establece por la dificultad en la comunicación. El objetivo del trabajo fue valorar el impacto de una estrategia de prevención implementada en pacientes sordos e hipoacúsicos. La Escue­la Especial N° 9 para sordos e hipoacúsicos “Helen Keller” de la ciudad de Corrientes, es una institución pública donde asisten 120 alumnos con diferentes capacidades auditivas. A los alumnos se los instruyó en el desarrollo de una correcta técnica de cepillado y se de­terminaron los índices Gingival y de placa bac­teriana, usando como estrategia para la trans­misión de la información, diferentes técnicas de comunicación. Los datos obtenidos fueron procesados utilizando el Programa Infostat. Se evaluaron 60 pacientes, 34 de sexo masculino y 26 de sexo femenino, con una edad prome­dio de I 1.2 años. El 84% de los pacientes pre­sentaron, en el primer control, valores compa­tibles con salud a nivel gingival (s a I) y el 94% presentó valores no compatibles con salud en cuanto a la presencia de placa bacteriana en la cavidad bucal (2 a 20%). En el segundo control, se incrementó el porcentaje de pacientes con grado 0. En el segundo control del índice de placa sólo los que recibieron información por medio de un intérprete demostraron descen­so en los valores. En los pacientes sordos y con deficiencias auditivas, no se logra una co­municación efectiva. Es necesaria la presencia de un intérprete, en el marco de las estrategias de prevención.

Year-long evaluation of total soluble proteins in the trunk of two pine species from northeastern Mexico

Objective: To quantify the one-year total soluble protein (TSP) concentration in the trunk of two pine species. Design/Methodology/Approach: The Bradford method (1976) was used to determine the TSP concentration in the two pine species. Statistical tests were subsequently performed with the IBM SPSS 18 Software, using a general linear model (GLM) univariate analysis. Results: The TSP concentration was different for each month. The highest concentration was recorded in August (6.84 mg gMS-1 for Pinus pinceana Gordon and 6.82 mg gMS-1 for Pinus cembroides Zucc), and the lowest was registered in April (5.53 mg gMS-1 for Pinus cembroides Zucc) and February (6.64 mg gMS-1 for Pinus pincenana Gordon). Study Limitations/implications: There is a lack of information regarding these two pine species and scarce studies explain the behavior of the TSP. Conclusions: The concentration of total soluble proteins varies in each month of the year. Further studies that include more plant organs are required to obtain a broader protein profile for both species

Re-theorising the core: a ‘globalized’ business elite in Santiago, Chile

World systems theory continues to be a widely adopted approach in theorisations of the contemporary world economy. An important epistemological component to world systems theory is the metaphor of core-periphery. Recent work within the approach has sought to transcend earlier criticisms of regional conceptions of cores, peripheries and semi-peripheries by an increasing sensitivity to local differences and an increasing emphasis on Wallerstein's original idea of core-periphery as process, operating at all scales in the contemporary world system. However, this paper argues that the core-periphery metaphor currently used by world systems theorists is founded around a restrictively narrow spatial epistemology. Such a narrow epistemology implements the core-periphery metaphor only as something which produces territorial outcomes in the physical world. This paper contends that recent work within the social services, concerned with the globalization debate and issues of spatial epistemology, should inform world systems theory in producing a reformulated spatial understanding of the core-periphery metaphor, embodying a wider conception of space to include abstract social spaces. This argument is developed in the notion that the world economy must also be understood as having a ‘social core’: a transnational diasporic business elite exercising decision-making power over the capitalist world system. The contention is grounded in the presentation of research into a case study of such a ‘globalized’ business elite in the capital city of Chile, Santiago

Dry matter distribution of banderita grass [Bouteloua curtipendula (Michx.) Torr.] at different plant strata

Objective: To evaluate the dry matter distribution of banderita grass [Bouteloua curtipendula (Michx.) Torr.] in different plant strata. Design/Methodology/Approach: A randomized block experimental design with five repetitions was used for the experiment. Each repetition consisted of three plants which were evaluated at different days after sowing (DAS), in three different plant strata: basal stratum (BS), middle stratum (MS), and upper or apical stratum (AS). The following variables were evaluated: dry matter yield (DMY), morphological composition (MC), leaf area (LA), plant height (PH), leaf:stem ratio (L:SR), and aerial part:root ratio (Ap:rR). An analysis of variance was performed, using the PROC GLM procedure of the SAS software; in addition, a comparison of means was carried out using Tukey’s test (α<0.05). Results: SB made a greater contribution to DMY at 50 DAS, with a 16 g DMY plant-1 average, followed by MS, with 9 g DM plant-1, and AS with 3 g plant-1. The MC (g) in the BS registered that the stem made a greater contribution than the rest of the components (average: 12.3 g plant-1), while leaves from the MS and AS made the greatest contribution (2.6 g plant-1) up to 64 DAS. However, they were surpassed by the stem in the MS and by the inflorescence in the AS. In addition, BS registered the highest LA (173.4 cm2). The largest PH was recorded at 120 DAS (96 cm). The highest L:SR ratio reached 1.10 at 50 DAS, while Ap:rR recorded 3.82 at 92 DAS. Study Limitations/Implications: The experiment was carried out under greenhouse conditions. Therefore, any extrapolation or comparison with field conditions should be done with caution. Findings/Conclusions: The basal and middle part of a banderita grass (Bouteloua curtipendula) plant contains the highest forage accumulation (mainly in the leaves and the stem), while the highest biomass content in the apical part is produced by the inflorescence