Microbial decomposition of corn residue in two Iowa Mollisols

Decomposition agent, Requate®, formulated by the Chinese company Chendu Hecheng Biological Technology CO., LTD, was examined for efficacy in agricultural plant-residue decomposition. We measured carbon dioxide (CO2) evolution over 21 days to determine the plant-residue decomposition rate. A Clarion soil (Typic Hapludoll) and Zea mays L. (corn) residue were characterized for several traits, including total C, total N, and C:N ratio. Our experiment included six treatments: no soil, no residue, no product (b); soil, no residue, no product (soil); soil, residue, no product (soilr); soil, no residue, product (soilp); soil, residue, product (soilrp); soil, residue, sterilized product (soilrsp). Our mesocosms simulated no-tillage with and without corn residue addition. Requate® product was applied to our treatments at the recommended rate of 86.6 g/2,221 L per hectare. Our sterile Requate® factor served to identify whether the product had a carrier that facilitated decomposition via stimulating the native microbiota. One soil moisture potential, -33 kPa, was used in this experiment. Univariate statistical analyses found no significant differences in corn-residue decomposition among our three treatments that included corn residue. We concluded that the Requate® product did not increase the rate of corn-residue decomposition in our Clarion soil. Microbial growth efficiency (MGE) was analyzed for isolated soil bacteria at three pH’s. In a stressed environment, we expected a greater level of C partitioned for cell maintenance than for microbial biomass C (MBC). Three Bacillus genus bacteria were isolated: B. pasteurii, B. circulans, and B. sphaericus. A characterized Webster soil (Typic Endoaquoll) was amended with Ca(OH)2 (calcium hydroxide) and Al2(SO4)3 (aluminum sulfate) to alter a soil pH of 6.5, to 7.5 and 5.5, respectively. Characterized corn residue was added and mixed into 100 g dry-weight Webster soil and placed inside a standard 0.47 L (pint) Mason jar (mesocosm). Corn residue (0.45 g) was added and mixed into the soil and then sterilized with high pressure saturated steam inside the mesocosm for 1 hr. The mesocosm was brought to room temperature (20-25°C) and then inoculated with a known quantity of our individual bacteria. Carbon dioxide and MBC were measured throughout a 35-day incubation period on days 3, 7, 14, 21, and 35. Our analysis determined that there was a significant difference in the rate of CO2 evolution (RCO2) by treatment and day. In general, RCO2 from all treatments was greater at day 3 and declined throughout the study; we measured significant differences in RCO2 on all days. B. pasteurii degraded the corn residue most rapidly, with the rate of decomposition being greater at pH 7.5 than pH 6.5 or 5.5. All other treatments followed a similar pattern, having greater rates of decomposition at pH 7.5. Microbial biomass C was greatest at pH 7.5 for all treatments and increased to a peak on day 21, where MBC was significantly different. The lowest MBC values were observed at pH 5.5 with B. circulans, followed by B. sphaericus, and then B. pasteurii. The least amount of MBC was observed when RCO2 was at its greatest. However, we could not determine the ratio of RCO2 per unit MBC produced because of measured negative MBC values. Thus, our data provided weak evidence that stressed cells required more metabolized C for cell maintenance but differences existed among the three isolates and an overall generalization could not be made

Neural network configuration for pollen analysis

Palynology is a botanical discipline devoted to the study of pollen and spores [1], focusing mainly on the analysis of the external morphology that presents structural patterns different from those of the variations in the exine, which is the external wall of the pollen grains. The study and microscopic analysis of its symmetry, wall opening, contour, shape, size, etc., have a taxonomic value and allows distinguishing different taxa at different levels: family, genera, species. The study of pollen grains is a difficult task, in its different phases, from small microscopic samples. The analysis of these is an important source of information for many scientific and industrial applications, making palynology a valuable tool for various areas of knowledge [1]. In palynology, neural networks have been successfully applied for the classification of pollen grains. For this purpose, RPROP was selected as a neural network training algorithm for the classification of a previously reported dataset

Presidencialismo y monarquía: ocaso y similitudes

El propósito central de este artículo es demostrar que el presidencialismo fue durante muchos años un régimen diseñado para disimular el poder omnímodo similar a una monarquía. Si bien es cierto no es igual a una monarquía presenta rasgos y tendencias en el ejercicio del poder que incluso las monarquías tradicionales pudieran envidiar. Entendemos por presidencialismo la forma de gobierno presidencial cuya figura y autoridad máxima es el presidente, heredero del poder del llamado tlatoani en Mesoamérica. Analizar comparativamente el presidencialismo con una monarquía pareciera aventurado e invita a la alarma en primer momento, y a la reflexión en un segundo, para cualquier ciudadano que habite en un Estado cuyo régimen sea el presidencialista y posea una idea por lo menos vaga de lo que una monarquía representa; para este individuo imaginario la respuesta al comparativo sería a priori negativa, toda vez que este ciudadano ha colaborado a la composición de los órganos constituidos del Estado mediante el voto libre, universal y secreto, sus gobernantes se han elegido de forma periódica, y además no es víctima de ningún tipo de violación a sus libertades de expresión o de asociación.A lo largo de la historia moderna de la democracia, y desde que Charles de Secondat escribe su obra L’espirit des lois en 1748 en donde plasma la teoría de la separación de poderes, grandes autores se han empeñado en consagrar esta teoría en una forma de gobierno ideal, misma que para la teoría liberal se consolidó en la forma de gobierno presidencial modelada en la constitución federal de los Estados Unidos de Norteamérica de 1787. Montesquieu escribe su obra, momentos en los cuales el régimen monárquico se encontraba en evidente desventaja frente al crecimiento del Parlamento inglés y la consolidación de la forma de gobierno parlamentaria, por lo cual se requería una nueva forma de gobierno que mantuviera, por lo menos medianamente, los privilegios de las élites favorecidas por la corona, es así como se concibe el régimen presidencial

Implementación de sistema web de atención al cliente para el área administrativa y ventas de la empresa JTS Contratistas Generales S.R.L.

La siguiente investigación con título de “Implementación de sistemas web de atención al cliente para el área administrativa y ventas de la empresa JTS Contratistas Generales S.R.L.”, definió como su principal objetivo, realizar la implementación de un software web el cual permita sistematizar el proceso de atención al cliente y obtener una mejora en la realización del procesamiento y también el almacenamiento de la información de los clientes de la empresa mencionada, así tener una alto nivel de seguridad en base a los datos de las mismas, que fue realizada aplicando la metodología RUP, con sus fases, el cual sirvió en la implementación del sistema, se realizó la implementación del método deductivo, se definió como una investigación de tipo experimental; asimismo, en la presente tesis se busca alimentar y corregir los problemas que se detectan en la empresa JTS Contratistas Generales que son, la carencia de tiempo para atenciones al cliente, la inexistencia de un banco de datos ordenados y clasificados adecuadamente que faciliten a los trabajadores de la empresa para que puedan resolver en el tiempo o plazo establecido lo requerido por los clientes, ya que las solicitudes se ingresan de forma manual, generan así problemas en la recepción de información y pérdida de datos, ya que no cuenta con un software que permita administrar y registrar de forma sistemática los datos de los clientes; en conclusión y conforme a la problemática se planteó la utilización de un sistema de atención al cliente en la empresa JTS Contratistas Generales S.R.L., mejora la atención al cliente en el plazo establecido, así como efectos favorables para la empresa en ganar más clientes

Unbalanced data processing using oversampling: machine Learning

Nowadays, the DL algorithms show good results when used in the solution of different problems which present similar characteristics as the great amount of data and high dimensionality. However, one of the main challenges that currently arises is the classification of high dimensionality databases, with very few samples and high-class imbalance. Biomedical databases of gene expression microarrays present the characteristics mentioned above, presenting problems of class imbalance, with few samples and high dimensionality. The problem of class imbalance arises when the set of samples belonging to one class is much larger than the set of samples of the other class or classes. This problem has been identified as one of the main challenges of the algorithms applied in the context of Big Data. The objective of this research is the study of genetic expression databases, using conventional methods of sub and oversampling for the balance of classes such as RUS, ROS and SMOTE. The databases were modified by applying an increase in their imbalance and in another case generating artificial noise

Factors that describe the use of digital devices in Latin American universities

Mobile digital devices are at the same time a tool for social interaction, an individual learning resource and can be a valuable contribution in the context of higher education to develop and promote new teaching and learning models. Recent studies show that both the more traditional pedagogical models of face-to-face teaching and distance teaching mediated by Virtual Learning Environments (VLE) can be enhanced by the use of these devices on and off campus. Likewise, the current context of Higher Education urges university institutions to promote a series of generic and specific competencies, where the use of these devices in a personal, academic and professional way acquires an outstanding value in the European Higher Education Area (EHEA), and represents an enrichment of university educational practice. This paper presents a study of the didactic and social use made by Hispanic American university students in 10 universities in several areas in order to establish common and divergent patterns of use so that useful conclusions can be extrapolated to improve the educational context of Higher Education in the Hispanic world

Analysis of design patterns for educational application development: serious games

Learning based on serious games is an emerging field in education, product of the proliferation of technological aids in the educational field and the necessary opening to new didactic methods that support the educator in the complexity of joining the transmission of knowledge and in the training in competences that comprise the learning process. In recent years, there has been a remarkable set of experiences in applying game-based learning to formal training scenarios, particularly in the higher education environment, which have encouraged the attempt to develop a working tool designed for the development of one of the most complex competences of the learning process and, at the same time, contradictory to individualism: teamwork. In this study, a serious game has been designed, with the aim of promoting and analyzing the development of teamwork skills. In this serious game, students have to solve a problem whose solution depends mainly on the ability to negotiate among group members

The scheduling algorithms for two-stage grid models

This paper deals with the scheduling of parallel works in a two-stage hierarchical grid. In this configuration, one of the great challenges is to assign the tasks in order to allow an efficient use of resources, while satisfying other criteria. In general, the optimization criteria are often in conflict. For solving this problem, a bi-objective genetic algorithm is proposed presenting an experimental study of six cross operators, and three mutation operators. The most influential parameters are determined through a statistical analysis of multifactorial variance which compares the proposal with five allocation strategies found in the literature

Servicio Web para el control de los procesos de la Jornada Universitaria de Desarrollo Científico (JUDC) basada en la arquitectura Api Rest en el Departamento de Computación de la UNAN-Managua, en el segundo semestre del 2016

Las Tecnologías de información y comunicación (TICS), permiten la manipulación de diferentes recursos tecnológicos en diversos procesos empresariales, que a la vez, son indispensables para alcanzar la competitividad frente a la alta gama de negocios existentes. Asimismo la transferencia de datos a través de internet es una herramienta útil para lograr una comunicación efectiva entre usuarios de larga distancia, como es el envío y recepción de correos electrónicos, y aún más brindar o consumir recursos de otras empresas a través de la conexión entre dos sistemas de información donde no tiene relevancia la plataforma en la que el sistema fue desarrollado, sino que solamente se solicitan los datos requeridos al que presta el servicio online y de esta forma completar y/o agilizar un proceso. Esto hace referencia a los llamados servicios web. En la universidad Nacional Autónoma de Nicaragua, Managua UNAN-Managua se realiza cada año la celebración de la Jornada Universitaria de Desarrollo Científico (JUDC) en sus distintas facultades. La facultad de ciencias e ingenierías posee varios departamentos en los cuales el Departamento de Computación cubre dos carreras importantes como son Ingeniería en Sistemas de Información e Ingeniería en Ciencias de la Computación. Para llevar a cabo la JUDC en el Departamento de Computación, se necesita inscribir a los estudiantes antes de la fecha de realización, y la evaluación de los proyectos durante la actividad, pero estos procesos se han realizado de manera manual y se requiere de mucho tiempo. Dada esta problemática y con el aprovechamiento de recursos existentes, se presenta el desarrollo de una aplicación web para control de los procesos referente a la Jornada Universitaria de Desarrollo Científico (JUDC) en el Departamento de Computación de la UNAN-Managua, con el cual se consume y brinda servicios, y de igual manera aligera adecuadamente las actividades involucradas en la JUDC