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Metal-ligand pair anisotropy in a series of mononuclear Er-COT complexes.
Synthetic control of the crystal field has elevated lanthanides to the forefront of single-molecule magnet (SMM) research, yet the resultant strong, predictable single-ion anisotropy has thus far not translated into equally impressive molecule-based magnets of higher dimensionality. This roadblock arises from the dual demands made of the crystal field: generate anisotropy and facilitate magnetic coupling. Here we demonstrate that particular metal-ligand pairs can dominate the single-ion electronic structure so fully that the remaining coordination sphere plays a minimal role in the magnitude and orientation of the magnetic anisotropy. This Metal-Ligand Pair Anisotropy (MLPA) effectively separates the crystal field into discrete components dedicated to anisotropy and magnetic coupling. To demonstrate an MLPA building unit, we synthesized four new mononuclear complexes that challenge the electronic structure of the iconic lanthanocene ([Ln(COT)2]+; COT2- = cyclooctatetraene dianion) complex which is known to generate strong anisotropy with Ln = Er3+. Variation in symmetry and coordination strength for Er(COT)I(THF)2 (THF = tetrahydrofuran) (1), Er(COT)I(Py)2 (Py = pyridine) (2), Er(COT)I(MeCN)2 (MeCN = acetonitrile) (3), and Er(COT)(Tp*) (Tp* = tris(3,5-dimethyl-1-pyrazolyl)borate) (4) shows that the Er-COT unit stabilizes anisotropy despite deliberate de-optimization. All four half-sandwich complexes display SMM behavior with effective energy barriers of U eff = 95.6(9), 102.9(3.1), 107.1(1.3), and 133.6(2.2) cm-1 for 1-4 by a multi-relaxation-process fitting. More importantly, the basic state splittings remain intact and the anisotropy axes are within several degrees of normal to the COT2- ring according to complete active space self-consistent field (CASSCF) calculations. Further investigation of the MLPA conceptual framework is warranted as it can provide building units with well-defined magnetic orientation and strength. We envision that the through-barrier processes observed herein, such as quantum tunneling, can be mitigated by formation of larger clusters and molecule-based materials
LIDERES RESILIENTES Y MANAGEMENT DEL EMPORIO COMERCIAL DE GAMARRA DEL DISTRITO DE LA VICTORIA. RESILIENT LEADERS AND MANAGEMENT OF GAMARRA COMMERCIAL EMPORIUM, “LA VICTORIA” DISTRICT.
RESUMENEn un mundo lleno de cambios, transformaciones e incertidumbre económica y financiera, ¿por qué algunas organizaciones fracasan y otras llegan a recuperarse con, incluso mejores resultados que antes.? Más que centrarse en las causas que generan esta situación, la resiliencia organizacional y en especial los lideres resilientes , crean ventajas competitivas sobre otras empresas, al saber administrar–management– las adversidades internas y externas , enfrentándolas, sobreponiéndolas y aprendiendo de ellas para fortalecerse.Las empresas que desarrollan la resiliencia son capaces de seguir proyectándose en el futuro a pesar de tener delante un entorno difícil y complicado que la crisis económica les está imponiendo, pero hay empresas que presentan un desempeño superior a otras, que no sólo subsisten sino que aún mejoran sus resultados.¿En qué se diferencian estas organizaciones de las que en su gran mayoría sufren los embates perniciosos de las situaciones críticas?Las empresas resilientes transmiten optimismo, resisten a la adversidad, saben adaptarse al entorno que les rodea, aprenden y desaprenden sin limitaciones, son capaces de mantener la confianza en lo que hacen, en su proyecto de empresa. El estudio, Lideres resilientes y management del emporio comercial de Gamarra, estuvo enmarcado dentro del nivel de investigación tipo descriptivo y explicativo con un estudio cualitativo y un diseño no experimental y se buscó determinar, como los lideres resilientes influyen en los procesos del management del emporio comercial de Gamarra del Distrito de la Victoria. La población estuvo conformada con una población de 364 comerciantes y una muestra 48 confeccionistas y textiles .Se privilegia la teoría de Wolin & Wolin (1993) que privilegia los argumentos de la resiliencia.Palabras claves : Lideres resilientes, Empresas resilientes, Management , Aprendizaje organizacional. SUMMARYIn a world full of changes, transformations and economic and financial uncertainty, why some organizations fail and others achieve to recover with even better results than before? Rather than focusing on the causes of this situation, especially organizational resilience and resilient leaders, create competitive advantages over other companies, to know how to manage - management - internal and external adversities facing them, endure them and learning from them to become stronger. Companies that develop resilience are able to continue projecting into the future despite having ahead a difficult and challenging environment that the economic crisis is imposing them, but there are companies that have a performance superior to others, which not only persist but even improve their results.What these organizations that mostly suffer the pernicious attacks of critical situations differ?Resilient companies transmit optimism, resisting adversity, know how to adapt to the environment around them, learn and unlearn without limitation, they are able to maintain confidence in what they do in their business project. The study, Resilient Leaders and management of the commercial emporium of Gamarra, was framed within the level of descriptive and explanatory type research with a qualitative study and a non-experimental design and sought to determine, as the resilient leaders influence the processes of management of the Emporium Gamarra commercial district of Victoria. The population consisted of a population of 364 dealers and a sample 48 garment manufacturers and textile .The theory favors Wolin & Wolin (1993) that favors the arguments of resilience. Keywords : Leaders resilient, resilient Business, Management, Organizational Learning
Funcionamiento familiar y su relación con el consumo de alcohol en adultos jóvenes
Family functionality plays a leading role when dealing with health problems, being a factor that, depending on the existing dynamics within the family system, will be a protective factor or in turn represent a risk factor for alcohol use in the person. The objective of the study was to determine the relationship between family functioning and alcohol use in young adults through a study methodology with a quantitative approach, correlational scope, non-experimental design, and cross section with a sample made up of 159 young adults (50.6% women and 49.4% men). The Family Functioning Test (FF-SIL) and The Alcohol Use Disorders Identification Test (AUDIT) were used. As results, the prevalence of perception of moderately functional family structures was identified with 55.3%, with respect to alcohol use it was determined at 74.2% with a low level of risk, there being a statistically significant difference between the sexes, being men who tend to consume more. Finally, it is concluded that there is no correlation between the study variables, which makes it possible to demonstrate the importance of continuing with studies that address the problem.La funcionalidad familiar juega un rol protagónico al tratarse de problemas de salud, siendo un factor que, dependiendo de la dinámica existente dentro del sistema familiar será un factor protector o a su vez representará un factor de riesgo para el consumo de alcohol en la persona. El objetivo del estudio fue determinar la relación entre el funcionamiento familiar y el consumo de alcohol en adultos jóvenes mediante una metodología de investigación con enfoque cuantitativo, de alcance correlacional, diseño no experimental y corte transversal, en una muestra conformada por 159 adultos jóvenes (50,6% mujeres y 49,4% hombres). Se empleó el Test de Funcionamiento Familiar (FF-SIL) y el Test de identificación de los Trastornos debido al consumo de alcohol (AUDIT). Como resultados se identificó la prevalencia de percepción de estructuras familiares moderadamente funcionales con el 55.3 %, respecto al consumo de alcohol se determinó al 74.2 % con un nivel bajo de riesgo, existiendo una diferencia estadísticamente significativa entre sexos, siendo los hombres quienes tienden a consumir más. Finalmente, se concluye en que no existe una correlación entre las variables de estudio, lo que permite evidenciar la importancia de continuar con estudios que aborden la problemátic
Evidence of suppression of onchocerciasis transmission in the Venezuelan Amazonian focus.
BACKGROUND: The World Health Organization (WHO) has set goals for onchocerciasis elimination in Latin America by 2015. Most of the six previously endemic countries are attaining this goal by implementing twice a year (and in some foci, quarterly) mass ivermectin (Mectizan®) distribution. Elimination of transmission has been verified in Colombia, Ecuador and Mexico. Challenges remain in the Amazonian focus straddling Venezuela and Brazil, where the disease affects the hard-to-reach Yanomami indigenous population. We provide evidence of suppression of Onchocerca volvulus transmission by Simulium guianense s.l. in 16 previously hyperendemic Yanomami communities in southern Venezuela after 15 years of 6-monthly and 5 years of 3-monthly mass ivermectin treatment. METHODS: Baseline and monitoring and evaluation parasitological, ophthalmological, entomological and serological surveys were conducted in selected sentinel and extra-sentinel communities of the focus throughout the implementation of the programme. RESULTS: From 2010 to 2012–2015, clinico-parasitological surveys indicate a substantial decrease in skin microfilarial prevalence and intensity of infection; accompanied by no evidence (or very low prevalence and intensity) of ocular microfilariae in the examined population. Of a total of 51,341 S. guianense flies tested by PCR none had L3 infection (heads only). Prevalence of infective flies and seasonal transmission potentials in 2012–2013 were, respectively, under 1 % and 20 L3/person/transmission season. Serology in children aged 1–10 years demonstrated that although 26 out of 396 (7 %) individuals still had Ov-16 antibodies, only 4/218 (2 %) seropositives were aged 1–5 years. CONCLUSIONS: We report evidence of recent transmission and morbidity suppression in some communities of the focus representing 75 % of the Yanomami population and 70 % of all known communities. We conclude that onchocerciasis transmission could be feasibly interrupted in the Venezuelan Amazonian focus. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13071-016-1313-z) contains supplementary material, which is available to authorized users
La gestión de tesorería en el sector público: alcances y retos para lograr la eficiencia en Latinoamérica
The purpose of the research was to describe and analyze the context of public treasury management in Latin America, which focused on recognizing the scope, the reality in which it is developed and the challenges that must be met for optimal operation. Various approaches have been considered that have made it possible to accurately identify the key factors for its optimal development, the existing problems and the agents with whom they interact, considering elements such as internal control, capital movement records and the performance of officials. This information was obtained through the method of systematic review of indexed scientific and academic literature from reliable portals such as Redalyc, Scielo, Academic Google and Ebsco, likewise, information delimitation criteria were presented, where the journals had to be in the interval of time between the years 2015 and 2021, obtaining 15 articles, which were analyzed in order to develop the discussion and conclusions useful for the area of study and improvement in performance.La investigación tuvo como finalidad describir y analizar el contexto de la gestión de tesorería pública en Latinoamérica, la cual se enfocó en reconocer los alcances, la realidad en la que se desarrolla y los retos que deben cumplirse para un funcionamiento óptimo. Se han considerado diversos enfoques que han permitido identificar con precisión los factores clave para su adecuado desenvolvimiento, las problemáticas existentes y los agentes con los que interactúan, considerándose elementos como el control interno, los registros de movimientos de capital y el desempeño de los funcionarios. Esta información fue obtenida a través del método de revisión sistemática de literatura científica y académica indexada proveniente de portales confiables como Redalyc, Scielo, Google académico y Ebsco, asimismo, se presentaron criterios de delimitación de información, donde las revistas tuvieron que encontrarse en el intervalo de tiempo comprendido entre los años 2015 y 2021, obteniéndose 15 artículos, que fueron analizados con la finalidad de desarrollar la discusión y las conclusiones de utilidad para el área de estudio y mejora en el desempeño
Geological Characterization, Mapping and Sampling of the Tailing Pond From Cerro El Toro, Region La Libertad-Perú
The present article shows the working methodology of the project field Development and validation of a clean technology for the integral treatment of neutralization of effluents and metallurgical tailings in the use of calcareous agents 1 Geological Characterization 2 Delimitation of the area of environmental influence for legal exploitation 3 Mapping 4 Sampling 5 Calculation of the volume of tailings 6 Study of the environmental impact of legal exploitation relationships It should be noted each one of these activities are important as part of the methodology of work in field which one are developed in the tailing Cerro El Toro which has been divided the aforementioned relationship into 73 sampling points grouped according to the relationships Salinas 1 Salinas 2 Salinas 3 Montoro and Melva whose volume has been determined through the software AutoCAD Civil which has determined that tailings have the following volume Salinas 1 1917 5 m3 Salinas 2 20331 48 m3 Salinas 3 18375 m3 Montoro 668 56 m3 y Melva 27945 5 m3 whose volume allowed the obtention of a representative sample of the tailing for been studied of their Environmental Quality of tailing which gives through the geochemical characterization analysis with the purpose of determining the Real Impact of the pollution of tailing in the mining communities of Shiracmaca and Coigobamb
El comportamiento organizacional en la gestión educativa pública: retos y perspectivas en el ámbito latinoamericano
The purpose of this article was to describe and analyze the environment of organizational behavior in public educational management in Latin America, through which it was possible to recognize the challenges that must be overcome for efficient management and the perspectives according to the context in which they are developed. Several approaches were considered, gathered from the analysis of the selected articles, which allowed recognizing key elements for the research, such as the implication of human capital management, leadership, communication, etc. The indexed scientific and academic literature was obtained through the systematic review method of articles obtained from reliable portals such as Redalyc, Scielo, Researchgate and Ebsco. The selected articles initially went through exclusion criteria, for this research it was considered that they belong to the time interval corresponding to the years 2015 to 2021, so that as a final result 15 articles were obtained, which were analyzed through analysis tables where the most relevant and useful information for the research was positioned, also, this allowed the development of the discussion and conclusions.El presente artículo tuvo como objetivo describir y analizar el entorno del comportamiento organizacional en la gestión educativa pública en el ámbito latinoamericano, mediante el cual se logró reconocer cuáles son los retos que deben superarse para una gestión eficiente y las perspectivas de acuerdo con el contexto donde se desarrollan. Se han considerado diversos enfoques recogidos del análisis correspondiente a los artículos seleccionados, que han permitido reconocer elementos clave para la investigación, como la implicancia de la gestión de capital humano, el liderazgo, la comunicación, etc. La literatura científica y académica indexada fue obtenida mediante el método de revisión sistemática de artículos obtenidos de portales confiables como Redalyc, Scielo, Researchgate y Ebsco. Los artículos seleccionados inicialmente pasaron por criterios de exclusión, para esta investigación se consideró que pertenezcan al intervalo de tiempo correspondiente entre los años 2015 y 2021, de tal manera que como resultado final se revisaron 15 artículos, los cuales fueron analizados a través de tablas de análisis donde se posicionó la información más relevante y útil para la investigación, asimismo, esta permitió el desarrollo de la discusión y conclusiones
Incidence of the collection of municipal taxes in the financing of the institutional budget: an application for the case of the provincial municipality of Puno-Peru, 2009-2020
El objetivo fue analizar la incidencia de los impuestos municipales en el financiamiento del presupuesto institucional de la municipalidad provincial de puno, en el periodo 2009-2020. Se utilizó la metodología cuantitativa, de tipo correlacional, donde se aplicó el modelo econométrico de máxima verosimilitud Log-Lin. Se pudo determinar que las recaudaciones de los impuestos municipales no son altamente significativas en el financiamiento del presupuesto institucional, ya que esta es explicado solo en un 42.11% por las recaudaciones de los impuestos municipales; sin embargo, el impuesto predial si fue significativo con un 54.15% de significancia en el financiamiento del presupuesto institucional.The objective was to analyze the incidence of municipal taxes in the financing of the institutional budget of the provincial municipality of Puno, in the period 2009-2020. The correlational quantitative methodology was used, where the maximum likelihood Log-Lin econometric model was applied. It was determined that municipal tax collections are not highly significant in financing the institutional budget, since this is explained only 42.11% by municipal tax collections; However, the property tax was significant with a 54.15% significance in financing the institutional budget
Introduction to magnetic resonance methods in photosynthesis
Electron paramagnetic resonance (EPR) and, more recently, solid-state nuclear magnetic resonance (NMR) have been employed to study photosynthetic processes, primarily related to the light-induced charge separation. Information obtained on the electronic structure, the relative orientation of the cofactors, and the changes in structure during these reactions should help to understand the efficiency of light-induced charge separation. A short introduction to the observables derived from magnetic resonance experiments is given. The relation of these observables to the electronic structure is sketched using the nitroxide group of spin labels as a simple example
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