In vitro biocontrol activity of Trichoderma harzianum on Alternaria alternata in the presence of growth regulators

http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200006&lng=es&nrm=isoThe in vitro biocontrol ability of Trichoderma harzianum on the phytopathogen Alternaria alternata improved in the presence of the growth regulators gibberellic acid (GA3), or indolacetic acid (IAA) or benzylaminopurine (BAP) or foliar nutrient at concentrations similar or higher than those used at the field level. These plant hormones decreased the secretion of endopolygalacturonase (endo-PG) of A. alternata by approximately 20%, did not modify endochitinase (endo-CH) secretion of T. harzianum and did not alter germination of conidia or mycelia growth of any of these fungi. The presence of T. harzianum decreased endo-PGase secretion of A. alternata by about 50%. This inhibitory effect was independent of the presence of growth regulators. The level of secreted endo-PG of T. harzianum was not modified by the presence of A. alternata, but the presence of this phytopathogen in cultures of T. harzianum, increased both the growth of the biocontroller and its secretion of endo-CH

The characteristic initial value problem for colliding plane waves: The linear case

The physical situation of the collision and subsequent interaction of plane gravitational waves in a Minkowski background gives rise to a well-posed characteristic initial value problem in which initial data are specified on the two null characteristics that define the wavefronts. In this paper, we analyse how the Abel transform method can be used in practice to solve this problem for the linear case in which the polarization of the two gravitational waves is constant and aligned. We show how the method works for some known solutions, where problems arise in other cases, and how the problem can always be solved in terms of an infinite series if the spectral functions for the initial data can be evaluated explicitly.Comment: 14 pages. To appear in Class. Quantum Gra

Turbulence kinetic energy equation for dilute suspensions

A multiphase turbulence closure model is presented which employs one transport equation, namely the turbulence kinetic energy equation. The proposed form of this equation is different from the earlier formulations in some aspects. The power spectrum of the carrier fluid is divided into two regions, which interact in different ways and at different rates with the suspended particles as a function of the particle-eddy size ratio and density ratio. The length scale is described algebraically. A mass/time averaging procedure for the momentum and kinetic energy equations is adopted. The resulting turbulence correlations are modeled under less retrictive assumptions comparative to previous work. The closures for the momentum and kinetic energy equations are given. Comparisons of the predictions with experimental results on liquid-solid jet and gas-solid pipe flow show satisfactory agreement

Estudio sobre Smart Contracts en Ethereum

Este trabajo fin de grado consiste en la exploración y el estudio de una tecnología con el objetivo de comprender su funcionamiento y confeccionar una guía que permita a un usuario nivel medio, adentrarse en ella y dar los primeros pasos con las ideas claras. La tecnología en cuestión es block chain y el elemento central hacia donde se orientan todos los conceptos son los smart contracts de la plataforma Ethereum . Se partirá desde ámbito general, explicando el funcionamiento y las características más relevantes de blockchain, ya que es esta la tecnología sobre la que se asientan Ethereum y sus smart contracts. Se mencionarán las características esenciales del prot ocolo que introdujo la tecnología blockchain por su relevancia y porque es el que se lleva toda la fama, Bitcoin. Por último, se abordará la plataforma Ethereum para explicar sus características, el funcionamiento de su máquina virtual, se profundizará en los smart contracts y se mostrarán unos conceptos básicos sobre el lenguaje de programación más utilizado para diseñarlos, Solidity.Ingeniería en Tecnologías de Telecomunicació

Applications of Engineering and Financial Analysis to the Valuation of Investments in Railroad Infrastructure

This record of study presents the findings of industry research projects performed during a one-year doctoral internship with the Austin Rail Group of HNTB Corporation. Four main internship objectives were established that address infrastructure problems related to the railroad industry and required the integration of engineering and financial analysis to develop effective project evaluation tools. Completion of the objectives resulted in: 1. Transformation of the Federal Railroad Administration methodology currently used to perform highway-railroad grade crossing analyses to a system of equations that can easily be used to evaluate regional rail infrastructure investments. Transportation engineering equations based on queuing theory were extended to new but equivalent formulations that accommodate unlimited, discrete train performance data from computer simulations of rail networks. 2. Application of risk assessment methods and railroad accident statistics to recommend a cost-effective alternative to legislative proposals to relocate hazardous materials transported by rail around metropolitan areas. A risk analysis model was developed to predict the risk of exposure from the release of a hazardous material following a train derailment so that changes in exposure achieved by alternative risk mitigation strategies could be observed. 3. A new method of measuring the susceptibility of railroads to financial distress following the catastrophic loss of a timber railroad bridge. Economic and finance principles were used to predict financial distress by determining of the number of revenue periods required to offset economic loss. 4. Demonstration of the use of financial market data in calculating the discount rate of public railroad companies for engineering analyses that involve negotiations with the public agencies. Surface Transportation Board rulings on the determination of a railroad?s cost of equity were applied to a comparative assessment of costs of capital for Class I railroads. A hypothetical example was used to demonstrate the interrelationship between engineering design strategies and their effects on the pricing of compensation to a railroad for right-of-way acquisition. These results, in fulfillment of the doctoral internship objectives, have provided HNTB with economic decision analysis tools and a series of conclusions used to provide recommendations to the Illinois, Missouri, and Texas Departments of Transportation, the Texas Legislature, and the railroad industry

Prosopis alba seed flour improves vascular function in a rabbit model of high fat diet-induced metabolic syndrome

Aims: Prosopis alba flour is a natural source of nutrient and phytochemicals with potential effects on cardiovascular risk factors. The aim of this work was to examine the effects of dietary supplementation with Prosopis alba seed flour (Pr-Feed) on a high fat diet (FD)-induced rabbit model of metabolic syndrome. Main methods: Rabbits were separated in four groups: fed regular diet (CD); CD supplemented with Pr-Feed; fed on 18 % FD; FD supplemented with Pr-Feed. All diets were administrated for 6 weeks. After the feeding period body weights, mean blood pressure, heart rate and visceral abdominal fat (VAF) were determined; glucose tolerance test (GTT) was performed; total cholesterol (TC), HDL-cholesterol, LDL-cholesterol, triglycerides (TG), fasting glucose (FG), aspartate amino transferase, alanine amino transferase, bilirubin and creatinine were measured in serum. Abdominal aorta was excised and vascular function was assessed by acetylcholine relaxation and contractile response to KCl, norepinephrine and angiotensin II. Key findings: Phytochemical analyses showed that the main compounds of Pr-Feed were apigenin C-glycosides. FD increased VAF, FG, TG, reduced HDL-cholesterol and induced abnormal GTT. Pr-Feed addition to FD did not modify these alterations. Aortic rings from rabbits fed on FD exhibited an impaired relaxation-response to acetylcholine and increased agonist vasoconstrictor responses. Pr Feed-supplemented FD improved the response to acetylcholine, and prevented the increase of the contractile response to KCl, norepinephrine and angiotensin II. Significance: Results suggest that dietary supplementation with Pr-Feed, rich in apigenin C-glycosides, has vascular protector properties and could be used to prevent vascular alterations characterizing the metabolic syndrome.Fil: Cattaneo, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Roco, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Alarcón, Gabriela del Jesús. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Isla, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Miguel Lillo; ArgentinaFil: Jerez, Susana Josefina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Miguel Lillo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

The initial value problem for colliding plane waves: the linear case

Einstein's equations are nonlinear, therefore, when gravitational waves meet, they must interact. This interaction process has been studied in detail for some cases, particularly those involving plane waves. To understand the structure of the space-time resulting from collisions of this type, many solutions have been generated. However, these have been obtained by first taking a "candidate" resulting space-time, and then extending it back to give rise to the originating waves. While these techniques are not too complex, it is not an easy task to obtain physically acceptable initial waves, and this is the greatest disadvantage of this indirect method. The main aim of this thesis is to consider a direct approach, to find a method that can overcome the difficulties indicated above, giving rise to solutions from arbitrary colliding plane waves. A well posed initial value problem is formulated for the collinear case. This is achieved by making use of generalised Abel transforms. This method is successfully tested for some particularly well-known cases. However, when it is applied to more general cases, a number of problems arise. Along the direct and inverse transformation process, there are several successive integrations involved, and it is in these integrations that the main difficulties appear, as the integrands themselves contain elliptic integrals. Nevertheless, a final way is found to obtain a final solution, which gives the solution as a series expansion involving hypergeometric functions. Consequently, assuming we can obtain the spectral functions generated by the Abel transforms, the problem would be theoretically solved, although the calculations tend to become extremely complicated when arbitrary colliding waves are taken

Embarazo adolescente

Este trabajo aborda principalmente los resultados obtenidos en una investigación realizada con adolescentes embarazadas, en el Barrio Isla del Río Diamante de San Rafael, entre los meses de enero del 2012 y abril del 2013. Se estudian los principales factores que están asociados al embarazo en las adolescentes, tales como pobreza, consumo de tóxicos y deserción escolar. La falta y/o distorsión de la información es otro de los factores que se relacionan con la ocurrencia de los embarazos adolescentes. Las adolescentes pertenecientes a familias disfuncionales, donde las relaciones entre padres o tutores son inadecuadas, violentas, con agresiones, y faltas de respeto, generan carencias afectivas y desapego, lo que en consecuencia impulsa a los adolescentes a la práctica de relaciones sexuales, en busca de ese amor que no tienen en el hogar. Investigaciones similares a la presente se han realizado en diferentes países con resultados equivalentes. En el capítulo I, se analiza lo definido como problema, en función de los datos recolectados en el Centro de Salud Nº159 Humberto Taranto del Barrio de la Isla del Río Diamante de San Rafael, se plantean los objetivos de la presente investigación, y se da cuenta de los trabajos que constituyen la estructura y el respaldo teórico de la investigación. En el capítuloII, se expone el diseño metodológico en donde está incluida la hipótesis del trabajo, variables consideradas, la selección de la muestra, los criterios de inclusión, el instrumento de recolección de datos y análisis y procesamiento de los datos. En el capítulo III, se aborda la interpretación de los resultados obtenidos, se realiza una propuesta de acción para difundir proyectos ya existentes y la conclusión de la tesis.Fil: Maya, Rita Paola. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Escuela de Enfermería..Fil: Roco, Rosa Janet. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Escuela de Enfermería.