Solving the CH4−_4^- riddle: the fundamental role of spin to explain metastable anionic methane

When atoms or molecules exist in the form of stable negative ions, they play a crucial role in the gas phase chemistry. Determining the existence of such an ion, its internal energy and its stability are necessary prerequisites to analyze the role of this ion in a particular medium. Experimental evidence of the existence of a negative methane ion CH$_4^-$ has been provided over a period of 50 years. However, quantum chemistry had not been able to explain its existence, and a detailed recent study has shown that the experimentally observed species cannot be described by the attachement of an electron in the ground state of CH$_4^-$. Here we describe CH$_4^-$ as being a metastable species in its lowest quartet spin state and we find that this species is a CH$_2^-$-:H$_2$ exciplex with three open shells, lying 5.8 eV above the methane singlet ground state but slightly below the dissociation fragments. The formation of charged exciplexes is a novel mechanism to explain small molecular anions with implications in a plethora of basic and applied research fields

Inteligencia emocional y el aprendizaje de los estudiantes de 7mo de básico de la Unidad Educativa Teodoro Kelly

La presente investigación titulada “Inteligencia Emocional y el Aprendizajede los Estudiantes de 7mo de Básico de la Unidad Educativa Teodoro Kelly, 2021” y tuvo como objetivo determinar la relación de la inteligencia emocional en el aprendizaje de los estudiantes de 7mo Básico de la Unidad Educativa TeodoroKelly. Se usó teorías de reconocidos investigadores, uno de los más importantes son Bar-On & Goleman muy conocidos por la denominación de la Inteligencia emocional y las organizaciones en este caso educativas lo que permitió tener un mejor enfoque sobre dichas variables. Mientras que en el proceso metodológico estuvo constituida en un tipo de estudio básico y de diseño descriptivocorrelacional. Al demostrar la correlación de las variables se encontró que la población logro en la prueba de correlación de rangos de Spearman, el puntaje de r =-,610 y un valor de p consignado de ,018 siendo este inferior al valor de p consignado de ,05 en razón se desaprueba la hipótesis independiente y aceptando la hipótesis del investigador, demostrando que hay una correlación positiva moderada entre la Inteligencia Emocional y el aprendizaje, relación a los estudiantes de 7mo Básico de la Unidad Educativa Teodoro Kelly. Se concluye que existe una correlación

Efecto de la aplicación de bacterias productoras de sustancias humicas mediante la biosolubilización de carbón de bajo rango en un suelo salino-sódico en el Valle del Cesar

La salinidad es un problema de degradación que es común en los suelos del Valle del Cesar y el departamento de la Guajira debido a la susceptibilidad que presentan por la presencia de sales y sodio elevados lo que afecta la productividad de los cultivos. Como alternativa para el manejo de la salinidad de los suelos se ha utilizado la aplicación de enmiendas orgánicas que permitan generar cambios favorables en las propiedades del suelo. Por tanto, el objetivo de esta investigación fue evaluar el efecto del carbón de bajo rango (CBR) y las bacterias solubilizadoras de carbón (BSC) Bacillus mycoides, Microbacterium sp y Acinetobacter baumannii sobre algunas propiedades químicas, biológicas y físicas de un suelo Salidic Calciustolls en el Valle del Cesar. Para ello se realizaron dos experimentos: uno en condiciones de invernadero y otro en campo que permitiera observar en un contexto real el efecto del CBR y las BSC. Como variables de respuesta se determinó la respiración del suelo, la actividad microbiológica mediante la hidrólisis del diacetato de fluoresceína (DAF), la actividad de enzimas ligninolíticas relacionadas con la biotransformación del carbón mediada por microorganismos. En complemento, se evaluaron algunas variables químicas asociadas a la salinidad sódica del suelo y la densidad aparente. Se encontró que el tratamiento del suelo con CBR al 1% bajo condiciones de invernadero favorece la actividad biológica, la cual se vio reflejada en el incremento de la respiración del suelo, la actividad de enzimas hidrolíticas sobre el DAF, la actividad de las enzimas lignino peroxidasas (LiP) y lacasas (Lac) asociadas a la biotransformación de CBR; también incrementó la capacidad de intercambio catiónico (CIC) y se registró una disminución en algunos parámetros químicos del suelo. En condiciones de campo la adición de CBR a razón de 5 kg de CBR/m2 contribuyó a disminuir la conductividad eléctrica (C.E.), la razón de absorción de sodio (RAS) y el porcentaje de sodio intercambiable (PSI); no se encontraron cambios significativos sobre el pH y la densidad aparente. En relación a los parámetros de actividad biológica se registraron incrementos en la respiración, la actividad microbiológica y la actividad de la actividad de las enzimas LiP, manganeso peroxidasa (MnP) y Lac; también se observó incrementos en la CIC. Los resultados de los dos experimentos muestran que hay un mayor efecto sobre las propiedades químicas y biológicas del suelo cuando se aplica el CBR en conjunto con las BSC, lo cual sugiere la posibilidad de utilizar y aprovechar el CBR como material orgánico humificado para el manejo de los suelos afectados por salinidad en el área de influencia de la minería del carbón en el Valle del Cesar, con ayuda de la microbiota que como se ha demostrado actúa sobre el CBR liberando la materia orgánica humificada.Abstract. Salinity is a problem of degradation that is common in the soils of the Valley of Cesar and Guajira Department due to susceptibility presented by the presence of salts and high sodium that affects crop productivity. As an alternative for the management of soil salinity has used the application of organic amendments that will generate favorable changes in soil properties. Therefore, the objective of this research was to evaluate the effect of low-rank coal (LRC) and coal-solubilizing bacteria (CSB) Bacillus mycoides, Microbacterium sp and Acinetobacter baumannii on chemical, biological and physical properties of a soil Salidic Calciustolls Valley of Cesar. For this, two experiments were performed: one in the greenhouse and one field that would be observed in a real context the effect of CBR and the BSC. As response variables soil respiration, microbiological activity by hydrolysis of fluorescein diacetate (DAF), ligninolytic activity related enzymes mediated biotransformation microorganisms coal were determined. In complement, some chemical variables associated with sodium soil salinity and bulk density were evaluated. It was found that treating the soil with LRC 1% under greenhouse conditions favors the biological activity, which was reflected in the increase in soil respiration activity of hydrolytic enzymes on the DAF, activity of enzymes lignin peroxidases (LiP) and laccase (Lac) associated with the biotransformation of LRC; also increased cationic exchange capacity (CEC) and a decrease was registered in some chemical soil parameters. Under field conditions the addition of LRC to reason 5 kg LRC/m2 contributed to decrease the electrical conductivity (EC), the sodium absorption ratio (SAR) and exchangeable sodium percentage (ESP); no significant change on the pH and the bulk density were found. In relation to the parameters of biological activity increases in respiration, microbiological activity and LiP enzymes, manganese peroxidase (MnP) and Lac activity were recorded; increases were also observed in the CEC. The results of the two experiments show that there is a greater effect on chemical and biological soil properties when the LRC is applied in conjunction with the CSB, which suggests the possibility to use and exploit the LRC as humified organic material for handling soils affected by salinity in the area of influence of coal mining in the Valle del Cesar, with the help of the microorganism as demonstrated acts on the LRC releasing the humified organic matter. Keywords:Maestrí

Efficiency of rhizobia selection in Rio Grande do Sul, Brazil using biological nitrogen fixation in Phaseolus lunatus

The aim of this research was to evaluate the capacity of symbiotic efficiency of native rhizobia from soils of the state of Rio Grande do Sul (RS), Brazil in Phaseolus lunatus L. plants. Soil and nodule samples from predominant legume plants such as Desmodium species were collected in seven locations of the state of RS. For the isolation of the rhizobia from the soil samples, lima bean “olho de cabra preto” variety and “leucena” (Leucena leucocephala) and plants were used as baits. Subsequently, the symbiotic characterization of the isolates was performed by inoculation on lima bean plants in vitro conditions. The selected bacterial isolates were evaluated for biological nitrogen fixation efficiency in a greenhouse experiment, being determined after: shoot dry mass, root dry mass, nodule dry mass, nitrogen (N) accumulated shoot and calculated the N fixation relative efficiency index. Among the 28 rhizobia isolates tested, 11 induced nodule formation in lima bean. The rhizobia Plu03 and Plu14 stimulated a greater increase of plant dry mass, nodule dry mass and nitrogen accumulation in the shoot, reflecting in a higher relative efficiency index. These results suggest that the isolates Plu03 and Plu14 are more efficient in promoting growth of lima bean, which could be recommended for future agronomic efficiency studies

Fundamentos del sistema tributario español.

Manual docente en Open Access para la asignatura de ''Sistema tributario'' del Grado en Derecho.PIE 22-132, ‘’La potenciación de la perspectiva profesional como elemento decisivo para una mejor adquisición de competencias por el estudiantado en el aprendizaje del Derecho Financiero y Tributario’’, financiado por la Universidad de Málaga

Pyoderma gangrenosum developing over an arteriovenous fistula scar

A 47-year-old man was admitted to our hospital for a radiocephalic arteriovenous fistula (AVF) in the right arm for dialytic treatment. His past medical history included Wegener granulomatosis diagnosed 8 years previously and chronic kidney disease for which he was receiving kidney replacement therapy in the form of haemodialysis for 7 years. Twenty-four hours after the operation, the patient complained of pain, fever, general discomfort and inflammation in the surgical area. He was admitted to hospital for monitoring and observation. The AVF was dismounted and ligatured and the aneurysmatic area removed and debrided. Response was positive for the first 24 h

Large-Scale Preventive Security-Constrained Unit Commitment Considering N-k Line Outages and Transmission Losses

This paper presents a new formulation for the preventive security-constrained unit commitment problem modeling N - k line outages and transmission losses. The pre- and post-contingency transmission constraints, representing N - k line outages, are explicitly included by using generalized generation distribution factors. To account for security, a contingency selection procedure based on line outage distribution factors finds a list of worst-case contingencies. Transmission losses are incorporated using piecewise linear expressions. The proposed model is formulated as an instance of mixed-integer linear programming. The effectiveness of the proposed approach is illustrated with the IEEE 57-bus system and the 1,354-bus portion of the European transmission system. As empirically evidenced, the explicit consideration of N-k line outages and transmission losses leads to different decisions in the generation scheduling and dispatch, ensuring secure power system operationEste artículo presenta una nueva formulación para el problema preventivo de compromiso de unidades con restricciones de seguridad que modela N - k cortes de línea y pérdidas de transmisión. Las restricciones de transmisión previas y posteriores a la contingencia, que representan N - k cortes de línea, se incluyen explícitamente mediante el uso de factores de distribución de generación generalizados. Para tener en cuenta la seguridad, un procedimiento de selección de contingencias basado en factores de distribución de cortes de línea encuentra una lista de contingencias en el peor de los casos. Las pérdidas de transmisión se incorporan utilizando expresiones lineales por partes. El modelo propuesto se formula como una instancia de programación lineal entera mixta. La efectividad del enfoque propuesto se ilustra con el sistema de 57 buses IEEE y la porción de 1354 buses del sistema de transmisión europeo. Como se demuestra empíricament

Effect of a low rank coal inoculated with coal solubilizing bacteria for the rehabilitation of a saline-sodic soil in field conditions

The aim of this research was to assessing changes on some chemical, biological and physical properties of a Salidic Calciustolls, in response enhanced by treatment with low rank coal (LRC) and coal solubilizing bacteria (CSB): Bacillus mycoides, Microbacterium sp and Acinetobacter baumannii, that release humified organic matter (HOM) due to biotrasnsformation of this coal. Over field conditions, plots of 5m2 were treated with the addition of LRC at a dose of 5kg/m2 and the inoculum of coal solubilizing bacteria in suspension of 1x108 bacteria.mL-1 at a dose of 100 mL/m2. Soil respiration, microbiological activity, lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase (Lac) enzyme activities were determined. The variables associated with saline sodic soils (electrical conductivity – EC, sodium adsorption ratio – SAR and exchangeable sodium percentage – ESP), cation exchange capacity (CEC) and bulk density (BD) also were determined. The LRC application contributed to the decrease of EC, SAR and ESP, but were not observed significant changes in pH. No significant changes were found in the BD; however, treatment was able to increase soil respiration, microbiological activity, and stimulation of LiP, MnP and Lac enzymes activity, as well as an increase in soil CEC. These results suggest the possibility of using the LRC as HOM source for the rehabilitation of degraded saline soils, considering that this kind of involvement is a common problem in soils of the Cesar River Valley in the Colombian Caribbean dry lands influenced by coal mining opencast. Keywords: lignite, humic substances, biotransformation coal, soil salinit

Efecto de la raza y período sobre algunas constantes fisiológicas de vacunos en Cajamarca.

Es trabajo de investigación consistió en desarrollar un estudio en vacunos sobre el efecto de las razas y períodos del día sobre cuatro constantes fisiológicas, en condiciones medioambientales de la ciudad de Chota.Por pare

Biological nitrogen fixation by rhizobium sp. native gliricidia (gliricidia sepium [jacq.] kunth ex walp.) under greenhouse conditions

An experiment was conducted under greenhouse conditions in order to evaluate the association and biological nitrogen fixation (BNF), six native strains of Rhizobium sp isolated from nodules gliricidia and a commercial strain (Rhizobiolc). Suspensions of 106 and 108 cells/mL for each of the strains studied and applied in two separate trials: the first with seeds and the second with seedlings 35 days of age gliricidia. In the seed test is calculated the cumulative percentage of germination for 7 days. In both trials after 42 days in seeds and seedlings 52 days in length was measured and stem diameter, leaf number, dry weight of aerial parts, number of nodules/plant and percentage of nitrogen. All treatments stimulated germination, growth and BNF, being better in the native strains at a concentration of 108 cells/mL, compared with the commercial strain and the control. These results indicate the positive effect exerted by Rhizobium sp., in promoting growth and BNF, which could be used for further studies to establish the production of a biofertilizer, allowing potentiate the production of crops by gliricidia for food arich cattle as source of protein in the Caribbean Biotechnology Center