Sostenibilidad ambiental y responsabilidad social en la actividad aurífera: el caso de Pierina (Ancash)

The research present had have two aspects: The environment sustain and social responsability. The environment sustain was studied the quality waters and the sediments in the three creaks mine Pierina: Creaks Pacchac, Pucauran and Llancash; thus the points: up river Mullaca of Santa river, point Lima, Jangas bridge and Paltay river, the result are part the research present. The particles material for sediments was done in the towns: Soledad, Shancayan, Llactash, Shimpi, Jangas and Carhuaz, going Huaylas route, obtained dust during 60 days, and this was analyzed As and Pb. Due to environment impact the Pierina mine will have a clousing mine and ricovering environment pasive and afflorestation wich are been excecuted and the future clousing of layers of lixiviation. This process last 9 years.At 2005 december the company has supply Us$99,7 millons for clousing mine.El presente estudio de investigación ha tratado dos aspectos: La sostenibilidad ambiental y la responsabilidad social. En esta primera fase se tratará lo concerniente a la sostenibilidad ambiental. En la sostenibilidad ambiental se ha estudiado la calidad de las aguas y de los sedimentos en las tres quebradas de influencia de la mina Pierina: Quebrada de Pacchac, quebrada de Pucauran y quebrada de Llancash; así como los puntos: Mullaca río arriba del río Santa, punto Lima, puente Jangas y río Paltay, los resultados forman parte del presente estudio. El monitoreo de material particulado por sedimentación ha sido efectuado en los siguientes puntos: La Soledad, Shancayan, caserío Llactash, caserío Shimpi, Jangas y Carhuaz, siguiendo la ruta del Callejón de Huaylas, determinando el material particulado en 60 días, y en estos polvos la determinación de arsénico y plomo. De acuerdo al estudio de impacto ambiental de la mina Pierina dispone de un cierre y recuperación de los pasivos ambientales y revegetación de los terrenos impactados que está en plena ejecución y el poscierre de las canchas de lixiviación y área de almacenamiento de desmonte cuya duración será de 7 años una vez que cierre la mina en el 2009. Al cierre de diciembre 2005, la compañía reconoció una provisión de US$ 99.7 millones en el pasivo, relacionada con sus obligaciones para el cierre y relleno futuro de las unidades mineras en las que opera

Neuronal Specialization for Fine-Grained Distance Estimation using a Real-Time Bio-Inspired Stereo Vision System

The human binocular system performs very complex operations in real-time tasks thanks to neuronal specialization and several specialized processing layers. For a classic computer vision system, being able to perform the same operation requires high computational costs that, in many cases, causes it to not work in real time: this is the case regarding distance estimation. This work details the functionality of the biological processing system, as well as the neuromorphic engineering research branch—the main purpose of which is to mimic neuronal processing. A distance estimation system based on the calculation of the binocular disparities with specialized neuron populations is developed. This system is characterized by several tests and executed in a real-time environment. The response of the system proves the similarity between it and human binocular processing. Further, the results show that the implemented system can work in a real-time environment, with a distance estimation error of 15% (8% for the characterization tests).Ministerio de Ciencia, Innovación y Universidades TEC2016-77785-

Estudio del proceso de extrusión del latón al bismuto y su maquinabilidad

The current study has determined that the materials from brass to bismuth, 1.11%, 1.46% and 2.48% respectively, have the following characteristics: the brass to bismuth material drawing, uniform round bar of 19 mm which microstructure is formed by α + β, shows inclusions of bismuth in the grain limits and in the same grain. The grain deformation is smaller on the surface, and it becomes bigger as it reaches the center. The mechanical properties of the 19 mm drawing material, I and II are bigger than the established by the ASTM B 16/B 16M, being the HRB hardness higher than the established by the norm. Also the material is wrought to obtain pieces for gas valves. The machinability index of the brass’s drawing materials that contains bismuth between 1.0 and 2.5% should be in a range from 85 and 90El presente estudio ha determinado que los materiales de latón al bismuto: 1.11%, 1.46% y 2.48%, respectivamente, presenten características como sigue: El material latón al bismuto trefilado, barra redonda uniforme de 19 mm, cuya microestructura está formado por cristales α + β presenta inclusiones de bismuto en los límites de grano y en el grano. La deformación del grano es más pequeño en la superficie, siendo mayor el grano a medida que se llegue al centro. Las propiedades mecánicas del material trefilado de 19 mm. I y II son mayores al establecido por la norma ASTM B 16/B 16M., siendo la dureza HRB mayor a lo establecido por dicha norma. Asimismo el material es forjable al obtenerse piezas de volante para las válvulas de gas. El índice de maquinabilidad de los materiales trefilados de latón que presenta bismuto entre 1.0 y 2.5 % deben estar entre 85 y 90

Cómo mejorar la extracción de oro en lixiviación en montón

In some cases it is easy to extract the gold present in an ore by conventional methods cyanidation heap , but in others, the results are very poor and may have originated in mineralogical intergrowths in atomic or sub - atomic size , presence of elements cianicidas and content of fine materials , our research is aimed at finding alternative precious metal , causing severe losses in the tailings gold . work is to show in what circumstances must bind the mineral to solve the problem when a solution presents interesting gold ore fines content and clay materials that are compact when wet and does not allow the cyanide used as a solvent , have mass reach reagent consumption, % moisture : contact with the poor percolation of leaching solutions , characteristic of a good binder machines used to bind minerals, determine the most appropriate economic binder and technically , the different effects are obtained when studying variables such as , curing time , addition of cyanide in the agglomeration step etc . The cost per agglomerate fluctuates around 10% of the total cost of operation is largely compensated by increasing the recovery of precious metals.En algunos casos es fácil extraer el oro presente en un mineral, por métodos convencionales de cianuración en montón, sin embargo en otros, los resultados son muy pobres y puede tener su origen en intercrecimientos mineralógicos en tamaños atómicos o sub-atómicos, presencia de elementos cianicidas y contenidos de materiales finos; nuestra investigación está orientada a encontrar alternativas de metales preciosos, causando severas pérdidas de oro en los relaves. el trabajo consiste en demostrar en qué circunstancias se debe aglomerar el mineral para solucionar el problema de solución cuando un mineral aurífero presenta interesante contenido de materiales finos y arcillosos porque al humedecerse forman masas compactas y no permite que el cianuro usado como solvente, llegue a tener contacto con los percolaciones pobres de soluciones lixiviantes, característica de un buen aglomerante, máquinas usadas para aglomerar minerales, determinar el aglomerante más apropiado económica y técnicamente, los diferentes efectos que se obtienen cuando se estudian variables tales como: consumo de reactivos, % de humedad, tiempo de curado, adicion de cianuro en la etapa de aglomeración etc. El costo por aglomerar fluctúa alrededor del 10% del costo total de operación que se compensa ampliamente al incrementar la recuperacion de metales preciosos

Wireless Sensor Network for Wildlife Tracking and Behavior Classification of Animals in Doñana

The study and monitoring of wildlife has always been a subject of great interest. Studying the behavior of wild animals is a difficult task due to the difficulties of tracking and classifying their actions. Nowadays, technology allows designing low-cost systems that make these tasks easier to carry out, and some of these systems produce good results; however, none of them obtains a high-accuracy classification because of the lack of information. Doñana National Park is a very rich environment with various endangered animal species. Thereby, this park requires a more accurate and efficient system of monitoring to act quickly against animal behaviors that may endanger certain species. In this letter, we propose a hierarchical, wireless sensor network installed in this park, to collect information about animals’ behaviors using intelligent devices placed on them which contain a neural network implementation to classify their behavior based on sensory information. Once a behavior is detected, the network redirects this information to an external database for further treatment. This solution reduces power consumption and facilitates animals’ behavior monitoring for biologists.Junta de Andalucía P12-TIC-130

ED-Scorbot: A Robotic test-bed Framework for FPGA-based Neuromorphic systems

Neuromorphic engineering is a growing and promising discipline nowadays. Neuro-inspiration and brain understanding applied to solve engineering problems is boosting new architectures, solutions and products today. The biological brain and neural systems process information at relatively low speeds through small components, called neurons, and it is impressive how they connect each other to construct complex architectures to solve in a quasi-instantaneous way visual and audio processing tasks, object detection and tracking, target approximation, grasping…, etc., with very low power. Neuromorphs are beginning to be very promising for a new era in the development of new sensors, processors, robots and software systems that mimic these biological systems. The event-driven Scorbot (EDScorbot) is a robotic arm plus a set of FPGA / microcontroller’s boards and a library of FPGA logic joined in a completely event-based framework (spike-based) from the sensors to the actuators. It is located in Seville (University of Seville) and can be used remotely. Spike-based commands, through neuro-inspired motor controllers, can be sent to the robot after visual processing object detection and tracking for grasping or manipulation, after complex visual and audio-visual sensory fusion, or after performing a learning task. Thanks to the cascade FPGA architecture through the Address-Event-Representation (AER) bus, supported by specialized boards, resources for algorithms implementation are not limited.Ministerio de Economía y Competitividad TEC2012-37868-C04-02Junta de Andalucía P12-TIC-130

Simultaneous imaging of hard and soft biological tissues in a low-field dental MRI scanner

[EN] Magnetic Resonance Imaging (MRI) of hard biological tissues is challenging due to the fleeting lifetime and low strength of their response to resonant stimuli, especially at low magnetic fields. Consequently, the impact of MRI on some medical applications, such as dentistry, continues to be limited. Here, we present three-dimensional reconstructions of ex-vivo human teeth, as well as a rabbit head and part of a cow femur, all obtained at a field strength of 260 mT. These images are the first featuring soft and hard tissues simultaneously at sub-Tesla fields, and they have been acquired in a home-made, special-purpose, pre-medical MRI scanner designed with the goal of demonstrating dental imaging at low field settings. We encode spatial information with two pulse sequences: Pointwise-Encoding Time reduction with Radial Acquisition and a new sequence we have called Double Radial Non-Stop Spin Echo, which we find to perform better than the former. For image reconstruction we employ Algebraic Reconstruction Techniques (ART) as well as standard Fourier methods. An analysis of the resulting images shows that ART reconstructions exhibit a higher signal-to-noise ratio with a more homogeneous noise distribution.We thank anonymous donors for their tooth samples, Andrew Webb and Thomas O'Reilly (LUMC) for discussions on hardware and pulse sequences, and Antonio Tristan (UVa) for information on reconstruction techniques. This work was supported by the European Commission under Grants 737180 (FET-OPEN: HISTO-MRI) and 481 (ATTRACT: DentMRI). Action co-financed by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana 2014-2020 (IDIFEDER/2018/022). Santiago Aja-Fernandez acknowledges Ministerio de Ciencia e Innovacion of Spain for research grant RTI2018-094569-B-I00.Algarín-Guisado, JM.; Díaz-Caballero, E.; Borreguero-Morata, J.; Galve, F.; Grau-Ruiz, D.; Rigla, JP.; Bosch-Esteve, R.... (2020). Simultaneous imaging of hard and soft biological tissues in a low-field dental MRI scanner. Scientific Reports. 10(1):1-14. https://doi.org/10.1038/s41598-020-78456-2S114101Haacke, E. M. et al. Magnetic Resonance Imaging: Physical Principles and Sequence Design Vol. 82 (Wiley-liss, New York, 1999).Bercovich, E. & Javitt, M. C. Medical imaging: from roentgen to the digital revolution, and beyond. Rambam Maimonides Med. J. 9, e0034. https://doi.org/10.5041/rmmj.10355 (2018).Mastrogiacomo, S., Dou, W., Jansen, J. A. & Walboomers, X. F. Magnetic resonance imaging of hard tissues and hard tissue engineered bio-substitutes. Mol. Imag. Biol. 21, 1003–1019. https://doi.org/10.1007/s11307-019-01345-2 (2019).Duer, M. J. 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Preoperative toxoplasma gondii serostatus does not affect long-term survival of cardiac transplant recipients: analysis of the Spanish Heart Transplantation Registry

[Abstract] Background. It's unclear whether pre-transplant T. gondii seropositivity is associated with impaired survival in heart transplant recipients. Objectives. To test the above-mentioned hypothesis in the Spanish Heart Transplantation Registry. Methods. Post-transplant outcomes of 4048 patients aged > 16 years who underwent first, single-organ heart transplantation in 17 Spanish institutions from 1984 to 2014 were studied. Long-term post-transplant survival and survival free of cardiac death or retransplantation of 2434 (60%) T. gondii seropositive recipients and 1614 (40%) T. gondii seronegative recipients were compared. Results. T. gondii seropositive recipients were older, had higher body mass index, and presented higher prevalence of hypertension, hypercholesterolemia, COPD and Cytomegalovirus seropositivity than T. gondii seronegative recipients. In univariable analysis, pre-transplant T. gondii seropositivity was associated with increased post-transplant all-cause mortality (non-adjusted HR 1.15; 95% CI 1.04–1.26). However, this effect was no longer statistically significant after multivariable adjustment by recipient's age and sex (adjusted HR 1.01, 95% CI 0.92–1.11). Extended multivariable adjustment by other potential confounders showed similar results (adjusted HR 0.99, 95% CI 0.89–1.11). T. gondii seropositivity had no significant effect on the composite outcome cardiac death or retransplantation (non-adjusted HR 1.08, 95% CI 0.95–1.24, p = 0.235). The distribution of the causes of death was comparable in T. gondii seropositive and T. gondii seronegative recipients. No statistically significant impact of donor's T. gondii serostatus or donor-recipient T. gondii serostatus matching on post-transplant survival was observed. Conclusions. Our analysis did not show a significant independent effect of preoperative T. gondii serostatus on long-term outcomes after heart transplantation

Flotación de minerales oxidados de plomo

The main oxidized lead minerals are: cerussite and anglesite, which due to their crystallography and wettability should not be buoyant, for this reason it is necessary to study the flotation properties for these minerals, the main ones are: solubility, surface physico-chemical , thermodynamics, fines content and others, it is concluded that anglesite is less buoyant than cerussite, both can be floated directly with amyl xanthate: long-chain hydrocarbon collector and cationic collectors such as alamine 26-D. The flotation of oxides improves when they are previously sulfurized before adding xanthate type collector, obtaining economically acceptable results. The above is applied to a polymetallic mineral of galena, sphalerite and cerussite; up to four flow charts are discussed, two are experimented, and with the bulk flotation scheme Pb-Zn, followed by flotation of oxides, after sulfurization with sodium sulfide excellent results are obtained, taking into account the complexity of the mineral.Los principales minerales oxidados de plomo son: cerusita y anglesita, los que debido a su cristalografía y mojabilidad no deberían ser flotables, por esta razón es necesario estudiar las propiedades de flotación para estos minerales, las principales son: solubilidad, físico-química de superficie, termodinámica, contenido de finos y otros, se concluye que la anglesita es menos flotable que la cerusita, ambas se pueden flotar directamente con xantato amílico: colector de cadena larga de hidrocarburo y colectores catiónicos como el alamine 26-D. La flotación de óxidos mejora cuando se sulfurizan previamente antes de adicionar colector tipo xantato, obteniéndose resultados económicamente aceptables. Lo anteriormente expuesto lo aplicamos a un mineral polimetálico de galena, esfalerita y cerusita; se discute hasta cuatro diagramas de flujo, se experimenta dos, y con el esquema de flotación bulk Pb-Zn, seguida de flotación de óxidos, previa sulfurización con sulfuro de sodio se obtienen excelentes resultados, teniendo en cuenta la complejidad del mineral