Regiones biogeográficas del género Cinchona L. (Rubiaceae- Cinchoneae)

Biogeographical regionalization’s are important tools to improve the management and knowledge of biodiversity. The chinchonas group is of high relevance for society because of its important socio cultural and medicinal values. Defining the biogeographic regions of Cinchona is of great importance. However, to date, the biogeographical regions of Cinchona remain undefined. The objective of this study is to identify and propose the biogeographical regions of the genus Cinchona. Based on species turnover methods, three macro biogeographical regions of the genus Cinchona (1- a macro region of chinchonas along the entire distribution range; 2- Loja region in northern Peru and southern Ecuador; 3- Peru region) five subregions (north, south, central, north-south-central, and central-south) and nine provinces were proposed. In conclusion, the results presented here provides updated information on the biogeography of the genus Cinchona, helping to document it importance for conservation of native genetic resources because these species have medicinal properties of use against tropical diseases such as malaria.Las regionalizaciones biogeográficas son herramientas útiles para la planificación y manejo de la biodiversidad. Las quinas o chinchonas son un grupo con alto valor sociocultural y medicinal, el cual requiere de una regionalización actualizada. Desafortunadamente, hoy en día las regiones biogeográficas del género Cinchona no han sido revisadas, ni formalmente descritas, y en particular, no han sido analizadas usando métodos de recambio de especies. El objetivo de este estudio es identificar y proponer las regiones biogeográficas del género Cinchona basadas en un índice de recambio de especies. Se identifican, describen y proponen tres macro regiones biogeográficas del género Cinchona: 1- una macro región de las chinchonas a lo largo de todo su rango de distribución; 2- la región de Loja, entre el norte del Perú y el sur del Ecuador; 3- la región del Perú, dividida en cinco subregiones: sur, norte, centro, norte-sur-centro, centro-sur y nueve provincias. Los análisis biogeográficos de este estudio presentan resultados actualizados sobre la biogeografía del género Cinchona, los cuales son de gran importancia para la conservación de recursos genéticos nativos, ya que la gran mayoría de sus especies tienen propiedades curativas contra enfermedades tropicales como la malaria

Curva característica de voltaje y corriente de un ADN autoensamblado

In this work, we numerically investigate the transport properties of two-dimensional square lattice patterns built from a telomeric DNA sequence, using an effective tight-binding model for the electronic structure, while the current is obtained within a Green’s function framework. We show that the self-assembled DNA structures based on telomeric DNA strands have current-voltage (I-V) characteristics, which make the system eligible for nanoelectronic applications.This paper shows a research on the transport properties of two-dimensional square lattice patterns built from a telomeric DNA sequence. A tight-binding model, and the recursive Green’s function method were used. It is showed that the self-assembled DNA structures based on telomeric DNA strands have current-voltage (I-V) characteristics, with robust plateau structures that favor the scrutiny of DNA-lead, as well as interference effects. An increase of the current, dependent on the distance between the crosses in the self-assembled square lattice structures, is observed, which makes the system eligible for nanoelectronic applications.Este artículo muestra un trabajo en el que se investigan numéricamente las propiedades de transporte de los patrones de una red cuadrada bidimensional construida a partir de una secuencia de ADN telomérico, a través de un modelo tight-binding efectivo para la estructura electrónica, mientras que la corriente se obtiene dentro del marco de funciones de Green. Se muestra que las estructuras de ADN autoensambladas basadas en cadenas de ADN teloméricas tienen características de voltaje de corriente con una robusta secuencia de escalones que favorecen el control del ADN con los contactos, así como los efectos de interferencia. Se observan variaciones interesantes del mecanismo de percolación, que dependen de la competencia entre la longitud de localización y la distancia entre los cruces en las estructuras de red cuadrada bidimensional autoensambladas, las cuales hacen que el sistema sea elegible para aplicaciones nanoelectrónicas. Este artigo mostra um trabalho no qual se pesquisam numericamente as propriedades de transporte dos padrões de uma rede quadrada bidimensional construída a partir de uma sequência de DNA telomérico, por meio de um modelo tight-binding efetivo para a estrutura eletrônica, enquanto a corrente é obtida dentro do âmbito de funções de Green. Mostra-se que as estruturas de DNA autoassembladas baseadas em correntes de DNA teloméricas têm características de voltagem de corrente com uma robusta sequência de etapas que favorecem o controle do DNA com os contatos, bem como os efeitos de interferência. Observam-se variações interessantes do mecanismo de percolação, que dependem da competição entre a longitude de localização e a distância entre os cruzamentos nas estruturas de rede quadrada bidimensional autoensambledas, as quais fazem que o sistema seja elegível para aplicações nano eletrônicas

Environmental Bio Economic Impact in Nicaragua

In this article the Bio economy of power plants connected to the national interconnected system of Nicaragua is analyzed, through the study of environmental effects of greenhouse gases emissions from the use of solid biomass from sugarcane bagasse and oil to generate electricity. In addition, an analysis of Cost - Benefit of investments to the electricity generation using fossil fuel and bagasse is done. The Methodology EX-Ante Carbon-balance Tool (EX-ACT) was used; this methodology was proposed by the United Nations Organization for Food and Agriculture (FAO) to determine the overall greenhouse gases (GHG) emission balance. Additionally, the WinDASI program, also developed by FAO, was used for the Cost - Benefit Analysis of investment in power plants. Furthermore, we performed marginal costing GHG reduction. The results show, that all plants are sources of GHG emissions, however the impact of sugar mills is partially positive by reforestation components and annual crops. However, the component inputs had negative environmental and socially impact. In the case of thermal power generation plants based on petroleum connected to the national grid, they were found to be sources of greenhouse gases. The analysis of the Benefit Cost in their investment indicates that there is a positive financially impact except in ALBANISA power plant and sugar Mills power plants

Environmental Bio Economic Impact in Nicaragua

In this article the Bio economy of power plants connected to the national interconnected system of Nicaragua is analyzed, through the study of environmental effects of greenhouse gases emissions from the use of solid biomass from sugarcane bagasse and oil to generate electricity. In addition, an analysis of Cost - Benefit of investments to the electricity generation using fossil fuel and bagasse is done. The Methodology EX-Ante Carbon-balance Tool (EX-ACT) was used; this methodology was proposed by the United Nations Organization for Food and Agriculture (FAO) to determine the overall greenhouse gases (GHG) emission balance. Additionally, the WinDASI program, also developed by FAO, was used for the Cost - Benefit Analysis of investment in power plants. Furthermore, we performed marginal costing GHG reduction. The results show, that all plants are sources of GHG emissions, however the impact of sugar mills is partially positive by reforestation components and annual crops. However, the component inputs had negative environmental and socially impact. In the case of thermal power generation plants based on petroleum connected to the national grid, they were found to be sources of greenhouse gases. The analysis of the Benefit Cost in their investment indicates that there is a positive financially impact except in ALBANISA power plant and sugar Mills power plants

Productivity Analysis in Power Generation Plants Connected to the National Grid: A New Case of Bio Economy in Nicaragua.

The purpose of this paper was to study the productivity where renewable energy resources and non-renewable resources for generating electricity in power plants connected to the national grid of Nicaragua were used. This article analyzed the total factor productivity of Bioeconomy for the generation of electricity from plants using sugarcane bagasse (biomass) as a renewable resource and petroleum. The data envelopment analysis (DEA) and the Malmquist index were used to measure the total factor productivity of power generation utilities connected to the national grid of Nicaragua. The results obtained by comparing sugar mills connected to the SIN was that Monte Rosa mill has a higher rate of increase in productivity due to the change of total factor productivity and when comparing thermal plants that employ petroleum products in power generation, the more efficient were ALBANISA, GECSA and TIPITAPA POWER; but when comparing thermal plants and some using renewable energy San Antonio sugar mill and ALBANISA were more efficient

Productivity Analysis in Power Generation Plants Connected to the National Grid: A New Case of Bio Economy in Nicaragua

The purpose of this paper was to study the productivity where renewable energy resources and non-renewable resources for generating electricity in power plants connected to the national grid of Nicaragua were used. This article analyzed the total factor productivity of Bioeconomy for the generation of electricity from plants using sugarcane bagasse (biomass) as a renewable resource and petroleum. The data envelopment analysis (DEA) and the Malmquist index were used to measure the total factor productivity of power generation utilities connected to the national grid of Nicaragua. The results obtained by comparing sugar mills connected to the SIN was that Monte Rosa mill has a higher rate of increase in productivity due to the change of total factor productivity and when comparing thermal plants that employ petroleum products in power generation, the more efficient were ALBANISA, GECSA and TIPITAPA POWER; but when comparing thermal plants and some using renewable energy San Antonio sugar mill and ALBANISA were more efficient

The structural impact of DNA mismatches

ABSTRACT The structure and dynamics of all the transversion and transition mismatches in three different DNA environments have been characterized by molecular dynamics simulations and NMR spectroscopy. We found that the presence of mismatches produced significant local structural alterations, especially in the case of purine transversions. Mismatched pairs often show promiscuous hydrogen bonding patterns, which interchange among each other in the nanosecond time scale. This therefore defines flexible base pairs, where breathing is frequent, and where distortions in helical parameters are strong, resulting in significant alterations in groove dimension. Even if the DNA structure is plastic enough to absorb the structural impact of the mismatch, local structural changes can be propagated far from the mismatch site, following the expected through-backbone and a previously unknown through-space mechanism. The structural changes related to the presence of mismatches help to understand the different susceptibility of mismatches to the action of repairing proteins

A novel application of entropy analysis for assessing changes in movement variability during cumulative tackles in young elite rugby league players

The aim of this study was to identify between-position (forwards vs. backs) differences in movement variability in cumulative tackle events training during both attacking and defensive roles. Eleven elite adolescent male rugby league players volunteered to participate in this study (mean ± SD, age; 18.5 ± 0.5 years, height; 179.5 ± 5.0 cm, body mass; 88.3 ± 13.0 kg). Participants performed a drill encompassing four blocks of six tackling (i.e. tackling an opponent) and six tackled (i.e. being tackled by an opponent while carrying a ball) events (i.e. 48 total tackles) while wearing a micro-technological inertial measurement unit (WIMU, Realtrack Systems, Spain). The acceleration data were used to calculate sample entropy (SampEn) to analyse the movement variability during tackles performance. In tackling actions SampEn showed significant between-position differences in block 1 (p = 0.0001) and block 2 (p = 0.0003). Significant between-block differences were observed in backs (block 1 vs 3, p = 0,0021; and block 1 vs 4, p = 0,0001) but not in forwards. When being tackled, SampEn showed significant between-position differences in block 1 (p = 0.0007) and block 3 (p = 0.0118). Significant between-block differences were only observed for backs in block 1 vs 4 (p = 0,0025). Movement variability shows a progressive reduction with cumulative tackle events, especially in backs and when in the defensive role (tackling). Forwards present lower movement variability values in all blocks, particularly in the first block, both in the attacking and defensive role. Entropy measures can be used by practitioners as an alternative tool to analyse the temporal structure of variability of tackle actions and quantify the load of these actions according to playing position

Épocas de nacimiento basadas en un índice climático para el ajuste de modelos estadísticos para peso vivo de ganado bovino en México

Artículo de investigación científica publicado en revista indizada.El objetivo fue comparar los efectos de una metodología para la clasificación de épocas climáticas, que tradicionalmente son utilizadas para establecer épocas de nacimiento (EN) en estudios y experimentos estadísticos. Esta metodología se basa en un índice de aridez (IA) para clasificar las EN utilizando información meteorológica histórica. Se trabajó una base de datos con un pedigrí de 7,460 animales, se ajustaron dos modelos para peso al nacimiento y peso al destete en bovinos Charolais manejados en pastoreo extensivo. Los modelos incluyeron el efecto fijo de grupo contemporáneo (GC= subclase de hato, sexo, año y EN) y edad de la madre. Los mismos modelos se compararon utilizando una clasificación tradicional de estaciones del año para clasificar las EN. Al estimar los componentes de varianza y valores genéticos (DEP) con sus exactitudes, los modelos fueron diferentes de acuerdo a la prueba de razón de verosimilitudes (P<0.01). El número de GC se redujo en 25 % para la EN basada en el IA, con GC con mayor número de individuos. El principal efecto observado en los modelos analizados fue el cambio en la jerarquización de las DEP para ambas características. Este método de clasificación de épocas de nacimiento, puede ayudar a mejorar el ajuste de modelos estadísticos en los sistemas ganaderos manejados en pastoreo extensivo

Electrochemical Impedance Spectroscopy (EIS): A Review Study of Basic Aspects of the Corrosion Mechanism Applied to Steels

AC impedance measurements have been applied for over twenty years in electrochemistry and physics to investigate the electrical properties of conductive materials and their interfaces using an external electrical impulse (VOLTAGE, V or CURRENT, I) as driving force. Furthermore, its application has recently appeared to be destined in the Biotechnology field as an effective tool for rapid microbiologic diagnosis of living organism in situ. However, there is no doubt that the electrochemical impedance spectroscopy (EIS) is still one of the most useful techniques around the world for metal corrosion control and its monitoring. Corrosion has long been recognized as one of the most expensive stumbling blocks that concern many industries and government agencies, because it is a steel destructive phenomenon that occurs due to the chemical interaction with aqueous environments and takes place at the interface between metal and electrolyte producing an electrical charge transfer or ion diffusion process. Consequently, it is experimentally possible to determine through the EIS technique the mechanism and control that kinectics of corrosion reactions encounter. First, EIS data is collected through a potentiostat/ galvanostat apparatus. After, it is fitted to a mathematical model (i.e. an equivalent electrical circuit, EEC) for its interpretation and analysis, fundamentally seeking a meaningful physical interpretation. Finally, this review reports some basic aspects of the corrosion mechanism applied to steels through the experimental EIS response using Nyquist or Bode plots. Examples are given for different applied electrochemical impedance cases in which steel is under study intentionally exposed to a corrosive aqueous solution by applying a sinusoidal potential at various test conditions