Diseño de malla de perforación para mejorar la productividad en el crucero 8946, en minera Coriwayra – 2022

El nivel de productividad de las empresas mineras gira en entorno a la perforación y voladura para extraer el mineral, de ello dependen las demás operaciones, por ello el objetivo general de este estudio es elaborar un diseño adecuado de malla para mejorar la productividad en el CX8946, CONSTRUCTORA S & MT SAC – 2022. Este estudio es cuasi experimental y está enfocado en recolectar datos numéricos utilizando instrumentos como una ficha de control de datos para los parámetros de perforación y voladura, y un formato de capacitación para el personal de operación mina. Durante esta investigación se realizó un diagnóstico del diseño de malla existente y las fallas en los procesos unitarios de perforación y voladura; luego se diseñó adecuadamente la malla de perforación y voladura considerando la evaluación geo mecánica de la roca, así como la técnica de voladura del recorte, así como un programa de capacitación y plan de supervisión basados en las causas raíz identificadas. Finalmente se determinó que el diseño de malla redujo los costos e incrementó los avances en la exploración para cortar las vetas auríferas, dando como resultado una mejor productividad, reduciendo los costos en un 8% y obteniendo un ahorro de 2115.29 mensuales.The level of productivity of mining companies revolves around drilling and blasting to extract the mineral, the other operations depend on it, therefore the general objective of this study is to develop an adequate mesh design to improve productivity in the CX8946, CONSTRUCTORA S & MT SAC – 2022. This study is quasi-experimental and is focused on collecting numerical data using instruments such as a data control sheet for drilling and blasting parameters, and a training format for mine operation personnel. During this investigation, a diagnosis was made of the existing mesh design and the failures in the unitary drilling and blasting processes; then the drilling and blasting grid was adequately designed considering the geomechanical evaluation of the rock, as well as the cutting blasting technique, as well as a training program and supervision plan based on the identified root causes. Finally, it was determined that the mesh design reduced costs and increased exploration advances to cut gold veins, resulting in better productivity, reducing costs by 8% and obtaining savings of 2115.29 monthly

Presencia de Aphis arbuti Ferrari y Wahlgreniella nervata (Gillete) (Hemiptera, Aphididae) en los madroños de la Comunidad de Madrid y estudio de la fumagina asociada.

Determinación de los pulgones asociados al madroño y su relación con los hongos desarrollados sobre la melaza

Imported eosinophilic fever with myositis: A diagnostic challenge

A 39-year-old caucasian man presented to our hospital in Barcelona with fever, dry cough, headache and weight loss of 4 kg. Symptoms started 5 days after returning from a 21-day travel to Malaysia. His physical examination was unremarkable except for a splenomegaly. Laboratory tests showed mild elevation of transaminases, elevated levels of lactate dehydrogenase (468 UI/L) and a normal blood cell count. Blood cultures, thick and thin blood smear and serologic tests for dengue, chikungunya, HIV, cytomegalovirus, Epstein-Barr virus, herpes virus 6, parvovirus B19, Toxoplasma spp and Rickettsia conorii were negative

High-pressure Raman study of Fe(IO3)3: Soft-mode behavior driven by coordination changes of iodine atoms

This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry C, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.jpcc.0c06541.[EN] We report high-pressure Raman spectroscopy studies of Fe(IO3)(3) up to nearly 21 GPa that have been interpreted with the help of density functional theory calculations, which include the calculation of phonon dispersion curves and elastic constants at different pressures. Zero-pressure Raman-active mode frequencies and their pressure dependences have been determined. Modes have been assigned and correlated to atomic movements with the help of calculations. Interestingly, in the high-frequency region, there are several modes that soften under compression. These modes have been identified as internal vibrations of the IO3 coordination polyhedron. Their unusual behavior is a consequence of the changes induced by pressure in the coordination sphere of iodine, which gradually change from a threefold coordination to an almost sixfold coordination under compression. The coordination change is favored by the decrease of the stereoactivity of the iodine lone electron pair so that likely a real sixfold coordination is attained after a first-order phase transition previously reported to occur above 21 GPa. The strong nonlinear behavior found in Raman-active modes as well as in theoretically calculated elastic constants has been discovered to be related to the occurrence of two previously unreported isostructural phase transitions at 1.5-2.0 and 5.7-6.0 GPa as shown by dynamic instabilities close to the Brillouin zone center.This work was supported by the Spanish Ministry of Science, Innovation and Universities, the Spanish Research Agency (AEI), the European Fund for Regional Development (ERDF, FEDER) under grants MAT2016-75586-C4-1/2/3-P, PID2019-106383GB-C41/42/43, and RED2018-102612-T (MALTA Consolider-Team Network), and the Generalitat Valenciana under grant Prometeo/2018/123 (EFIMAT). A.L. and D.E. would like to thank the Generalitat Valenciana for the Ph.D. fellowship GRISOLIAP/2019/025).Liang, A.; Rahman, S.; Rodriguez-Hernandez, P.; Muñoz, A.; Manjón, F.; Nenert, G.; Errandonea, D. (2020). High-pressure Raman study of Fe(IO3)3: Soft-mode behavior driven by coordination changes of iodine atoms. The Journal of Physical Chemistry C. 124(39):21329-21337. https://doi.org/10.1021/acs.jpcc.0c06541S21329213371243

RAD51 restricts DNA over-replication from re-activated origins

Eukaryotic cells rely on several mechanisms to ensure that the genome is duplicated precisely once in each cell division cycle, preventing DNA over-replication and genomic instability. Most of these mechanisms limit the activity of origin licensing proteins to prevent the reactivation of origins that have already been used. Here, we have investigated whether additional controls restrict the extension of re-replicated DNA in the event of origin re-activation. In a genetic screening in cells forced to re-activate origins, we found that re-replication is limited by RAD51 and enhanced by FBH1, a RAD51 antagonist. In the presence of chromatin-bound RAD51, forks stemming from re-fired origins are slowed down, leading to frequent events of fork reversal. Eventual re-initiation of DNA synthesis mediated by PRIMPOL creates ssDNA gaps that facilitate the partial elimination of re-duplicated DNA by MRE11 exonuclease. In the absence of RAD51, these controls are abrogated and re-replication forks progress much longer than in normal conditions. Our study uncovers a safeguard mechanism to protect genome stability in the event of origin reactivation

Redox and Catalytic Properties of Promoted NiO Catalysts for the Oxidative Dehydrogenation of Ethane

[EN] NiO and metal-promoted NiO catalysts (M-NiO, with a M/(M+Ni) atomic ratio of 0.08, with M = Nb, Sn, or La) have been prepared, tested in the oxidative dehydrogenation (ODH) of ethane, and characterized by means of XRD, TPR, HRTEM, Raman, XPS, and in situ XAS (using H-2/He, air or C2H6/He mixtures). The selectivity to ethylene during the ODH of ethane decreases according to the following trend: Nb NiO Sn NiO > La NiO > NiO, whereas the catalyst reducibility (determined by both TPR and XAS using H-2/He mixtures) shows the opposite trend. However, different reducibility and catalytic behavior in the absence of oxygen (ethane/He mixtures) have been observed, especially when comparing Nb- and Sn-promoted NiO samples. These differences can be ascribed mainly to a different phase distribution of the promoter. The results presented here are discussed in terms of the nature of active and selective sites for ODH of ethane in selective and unselective catalysts, but also the role of promoters and the importance of their phase distribution.The authors would like to acknowledge the DGICYT in Spain CTQ2012-37925-C03-2, CTQ2015-68951-C3-1-R, and CTQ2015-68951-C3-3-R. Authors thank European Synchrotron Radiation Facility, ESRF (Project CH-4512; BM25-SpLine Beamlime). Authors from ITQ also thank Project SEV-2016-0683 for financial support. D.D. thanks MINECO and Severo Ochoa Excellence Program for his fellowship (SVP-2014-068669). B.S. also thanks UV-INV-AE16-484416. Finally, the authors thank the Electron Microscopy Service of Universitat Politecnica de Valencia for their support.Delgado-Muñoz, D.; Solsona Espriu, BE.; Ykrelef, A.; Rodriguez-Gomez, A.; Caballero, A.; Rodríguez-Aguado, E.; Rodriguez-Castellón, E.... (2017). Redox and Catalytic Properties of Promoted NiO Catalysts for the Oxidative Dehydrogenation of Ethane. The Journal of Physical Chemistry C. 121(45):25132-25142. https://doi.org/10.1021/acs.jpcc.7b07066S25132251421214

Perfil de salud y estilo de vida de los estudiantes de medicina de la Universidad Surcolombiana, Neiva 2010

En varios estudios se ha demostrado que los hábitos y comportamientos del estilo de vida de las personas se pueden comportar como factores protectores o como factores de riesgo para la salud. Los estudiantes universitarios hacen parte de un grupo poblacional en un contexto que condiciona una serie de características no saludables de su estilo de vida. El presente estudio pretende lograr una aproximación a las características del estilo de vida de los estudiantes de Medicina de la Universidad Surcolombiana. Se realizó un estudio de corte transversal, definiendo variables que corresponden a las dimensiones de la naturaleza humana. A partir de su operacionalización se aplicó un cuestionario diseñado por el Departamento de Medicina Familiar de la Universidad McMasterde Canadá, modificado por el Centro de Estudios de Salud y Bienestar Humano de la Universidad de La Habana, ajustado por los autores para el presente estudio, debidamente estandarizado, previa administración de una prueba piloto a 20 estudiantes del programa de Medicina. El universo de estudio fue 410 estudiantes de Medicina matriculados para el semestre 2009-2. Los datos recopilados se clasificaron a partir de las variables definidas, se tabularon en una matriz de vaciamiento y fueron analizados en función de los objetivos planteados, con proceder inductivo se formularon las consideraciones finales, válidas para el universo estudiado. Se encontró que el estilo de vida de los estudiantes de Medicina de la Universidad Surcolombiana, se caracteriza por el escaso ejercicio físico semanal, la ingestión de una dieta inadecuada, el uso frecuente de bebidas alcohólicas y problemas de sueño, descanso y estrés. Ante esta problemática se recomienda el diseño e implementación de una estrategia de intervención fundamentada en la promoción de la salud desde la visión aportada por la sanología

NiO diluted in high surface area TiO2 as efficient catalysts for the oxidative dehydrogenation of ethane

[EN] Catalysts consisting of NiO diluted in high surface area TiO2 can be as efficient in the oxidative dehydrogenation of ethane as the most selective NiO-promoted catalysts reported previously in the literature. By selecting the titania matrix and the NiO loading, yields to ethylene over 40% have been obtained. In the present article, three different titanium oxides (TiO2) have been employed as supports or diluters of nickel oxide and have been tested in the oxidative dehydrogenation of ethane to ethylene. All TiO2 used present anatase as the main crystalline phase and different surface areas of 11,55 and 85 m(2) g(-1). It has been observed that by selecting an appropriate nickel loading and the titanium oxide extremely high selectivity towards ethylene can be obtained. Thus, nickel oxide supported on TiO2 with high surface areas (i.e. 55 and 85 m(2) g(-1)) have resulted to give the best catalytic performance although the optimal nickel loading is different for each case. The optimal catalyst has been obtained for NiO-loadings up to 5-10 theoretical monolayers regardless of the TiO2 employed. Free TiO2 is inactive whereas unsupported NiO is active and unselective (forming mainly carbon dioxide) and, therefore, unmodified NiO particles have to be avoided in order to obtain the optimal catalytic performance. The use of low surface area titania (11 m(2) g(-1)) have led to the lowest selectivity to olefin due to the presence of an excess of free NiO particles. (C) 2017 Elsevier B.V. All rights reserved.The authors would like to acknowledge the DGICYT in Spain CTQ2012-37925-C03-2, CTQ2015-68951-C3-1-R, CTQ2015-68951-C3-3-R and SEV-2012-0267 Projects for financial support. D.D. also thanks Severo Ochoa Excellence fellowship (SVP-2014-068669). We also thank the University of Valencia (UV-INV-AE-16-484416 project) and SCSIE-UV for assistanceSanchis, R.; Delgado-Muñoz, D.; Agouram, S.; Soriano Rodríguez, MD.; Vázquez, MI.; Rodriguez-Castellon, E.; Solsona, B.... (2017). NiO diluted in high surface area TiO2 as efficient catalysts for the oxidative dehydrogenation of ethane. Applied Catalysis A General. 536:18-26. https://doi.org/10.1016/j.apcata.2017.02.012S182653

Positive direct antiglobulin test in post-artesunate delayed haemolysis: more than a coincidence?

Background: Delayed haemolysis is a frequent adverse event after treatment with artesunate (AS). Removing onceinfected “pitted” erythrocytes by the spleen is the most accepted mechanism of haemolysis in these cases. However, an increasing number of cases with positive direct antiglobulin test (DAT) haemolysis after AS have been reported. Methods: All malaria cases seen at Hospital Clinic of Barcelona between 2015 and 2017 were retrospectively reviewed. Clinical, parasitological and laboratory data from patients treated with intravenous artesunate—specifcally looking for delayed haemolysis and DAT—was collected. Results: Among the 36 severe malaria patients treated with artesunate at the hospital, 10 (27.8%) developed postartesunate delayed haemolysis. Out of these, DAT was performed in six, being positive in four of them (at least 40%). DAT was positive only for complement—without IgG—suggesting drug-dependent immune-haemolytic anaemia of the immune-complex type. Three of the four patients were treated with corticosteroids and two also received blood transfusion, with a complete recovery. Conclusions: Drug-induced auto-immune phenomena in post-artesunate delayed haemolysis may be underre‑ ported and must be considered. The role of corticosteroids should be reassessed

Positive direct antiglobulin test in post-artesunate delayed haemolysis: more than a coincidence?

BACKGROUND: Delayed haemolysis is a frequent adverse event after treatment with artesunate (AS). Removing once-infected 'pitted' erythrocytes by the spleen is the most accepted mechanism of haemolysis in these cases. However, an increasing number of cases with positive direct antiglobulin test (DAT) haemolysis after AS have been reported. METHODS: All malaria cases seen at Hospital Clinic of Barcelona between 2015 and 2017 were retrospectively reviewed. Clinical, parasitological and laboratory data from patients treated with intravenous artesunate-specifically looking for delayed haemolysis and DAT-was collected. RESULTS: Among the 36 severe malaria patients treated with artesunate at the hospital, 10 (27.8%) developed post-artesunate delayed haemolysis. Out of these, DAT was performed in six, being positive in four of them (at least 40%). DAT was positive only for complement-without IgG-suggesting drug-dependent immune-haemolytic anaemia of the immune-complex type. Three of the four patients were treated with corticosteroids and two also received blood transfusion, with a complete recovery. CONCLUSIONS: Drug-induced auto-immune phenomena in post-artesunate delayed haemolysis may be underreported and must be considered. The role of corticosteroids should be reassessed