Análisis de la eficacia en el cumplimiento del estándar internacional de responsabilidad social empresarial, Norma SA8000, en las prácticas de relaciones laborales de la compañía minera Antamina en el año 2017

En la actualidad el sector minero en el Perú es el principal actor en términos de representación del PBI, a través de sus considerables contribuciones económicas y los múltiples puestos de trabajo generados; sin embargo es la industrias que presenta los más altos índices de conflictos socio-ambientales, evidenciando así su falta de Responsabilidad Social Empresarial en muchas de sus prácticas. De este modo las consecuencias se plasman en hechos como las múltiples huelgas de trabajadores de las empresas mineras, las cuales generan una gran cantidad de horas hombres perdidas, factor de ineficiencia para la gestión de personas y un golpe para la economía. En ese sentido, la presente investigación plantea mostrar que dentro de la industria minera existen excepciones a la regla, las cuales deben ser tomadas como ejemplo para replicar sus prácticas de relaciones laborales y así mejorar la imagen del sector minero tanto en nuestro país como posiblemente en el mundo. De este modo, utilizado como instrumento principal el estándar internacional de Responsabilidad Social Empresarial interna de Buenas Prácticas de relacionales laboral de la Norma SA8000, se pretende analizar el nivel de cumplimiento de las prácticas de relaciones laborales de la Compañía Minera Antamina, una empresa de gran minería tomada como objeto de estudio, respecto de las exigencias de la SA8000. Para ello, en el trabajo de investigación, se identificaron cuáles eran los requisitos y criterios que componían la Norma SA8000 para evaluar el cumplimiento de los mismos por parte de las prácticas de Antamina, empezando por la recolección de información, en la cual se utilizaron entrevistas a trabajadores de la organización y observaciones a realidades y documentos relacionados a las operaciones de la organización. Asimismo, se aplicaron encuestas a expertos, en temas de Responsabilidad Social Empresarial interna y en temas de Relaciones Laborales, para que según su experiencia y conocimiento de sus temas de especialidad en base a la realidad minera peruana le atribuyan un peso porcentual de valoración a cada requisito, de modo que tras un adecuado análisis se pueda definir un grado de relevancia distinto a cada requisito que los haga más o menos relevante para la evaluación del cumplimiento del estándar de la Norma SA8000. Es tras ello que aplicando un adecuado análisis en una Rúbrica Holística y algunos análisis posteriores la investigación logra dar a conocer el exacto nivel de eficacia en el cumplimiento del estándar internacional de Responsabilidad Social Empresarial, Norma SA8000, de las prácticas de Relaciones Laborales de Antamina en el año 2017. Ello concluyendo que si bien Antamina logra en gran medida cumplir con los requisitos de la Norma SA8000, existen pequeñas brechas que no permiten el 100% del cumplimiento frente a la misma; es en base a estas brechas que se han planteado una serie de recomendaciones a seguir, las cuales al final de la investigación fueron validadas por la misma Compañía Minera Antamina.Tesi

High-Resolution Boundary Detection for Medical Image Segmentation with Piece-Wise Two-Sample T-Test Augmented Loss

Deep learning methods have contributed substantially to the rapid advancement of medical image segmentation, the quality of which relies on the suitable design of loss functions. Popular loss functions, including the cross-entropy and dice losses, often fall short of boundary detection, thereby limiting high-resolution downstream applications such as automated diagnoses and procedures. We developed a novel loss function that is tailored to reflect the boundary information to enhance the boundary detection. As the contrast between segmentation and background regions along the classification boundary naturally induces heterogeneity over the pixels, we propose the piece-wise two-sample t-test augmented (PTA) loss that is infused with the statistical test for such heterogeneity. We demonstrate the improved boundary detection power of the PTA loss compared to benchmark losses without a t-test component

Analysis and Design of a Wideband Low-Noise Amplifier with Bias and Parasitic Parameters Derived Wide Bandpass Matching Networks

This paper proposes a 110% relative bandwidth (RBW) low-noise amplifier (LNA) for broadband receivers with flat gain, low noise and high linearity. Bias and parasitic parameters derived wide bandpass (BPDWB) matching networks and a cascode with dual feedbacks are introduced for broadband performance. Matching network design procedures are demonstrated, and results show that the frequency response of the network fits the target impedance well from 1 GHz to 3.5 GHz. The proposed BPDWB network improves the design efficiency and enhances the prediction accuracy of impedance matching. The proposed LNA in 0.25 μm GaAs pseudomorphic high electron mobility transistor (GaAs pHEMT) technology realizes a minimum NF of 0.45 dB at 1.6 GHz where the NF is less than 0.55 dB within the operating frequency band. A flat gain of 22.5–25.2 dB is achieved with the input voltage standing wave ratio (VSWR) below 1.22 and output VSWR less than 2.5. In addition, the proposed LNA has good linearity where the output third-order intercept point (OIP3) is better than +31.5 dBm, and the output 1 dB compression point (OP1dB) is better than +19 dBm over the wide frequency range

Analysis and Design of a Wideband Low-Noise Amplifier with Bias and Parasitic Parameters Derived Wide Bandpass Matching Networks

This paper proposes a 110% relative bandwidth (RBW) low-noise amplifier (LNA) for broadband receivers with flat gain, low noise and high linearity. Bias and parasitic parameters derived wide bandpass (BPDWB) matching networks and a cascode with dual feedbacks are introduced for broadband performance. Matching network design procedures are demonstrated, and results show that the frequency response of the network fits the target impedance well from 1 GHz to 3.5 GHz. The proposed BPDWB network improves the design efficiency and enhances the prediction accuracy of impedance matching. The proposed LNA in 0.25 μm GaAs pseudomorphic high electron mobility transistor (GaAs pHEMT) technology realizes a minimum NF of 0.45 dB at 1.6 GHz where the NF is less than 0.55 dB within the operating frequency band. A flat gain of 22.5–25.2 dB is achieved with the input voltage standing wave ratio (VSWR) below 1.22 and output VSWR less than 2.5. In addition, the proposed LNA has good linearity where the output third-order intercept point (OIP3) is better than +31.5 dBm, and the output 1 dB compression point (OP1dB) is better than +19 dBm over the wide frequency range

Defective structures in FeCrAl alloys from first principles calculations

The FeCrAl alloy system is well known as a potential candidate material for the accident tolerant fuel (ATF) cladding in the nuclear power industry owing to its high oxidation resistance under irradiation and high-temperature environment. The mechanical properties of FeCrAl alloys with various defects degrade under irradiation condition. In the present work, the structures of FeCrAl alloys with 10 similar to 15Cr wt% and 5 similar to 6Al wt% were simulated from the first principles calculations. Mechanical properties were predicted for FeCrAl alloys with different defects and components. Calculated results showed that doping Cr into alloys may improve its mechanical properties. On the other hand, Al was predicted to downgrade the mechanical properties by replacing the Fe atom. The mechanical anisotropies of FeCrAl were researched through Zener's index and 3D Young's modulus sketches. Additionally, the investigation on electronic characteristics indicated that an attenuated Fe-Fe interaction and strengthened Fe-Al interactions occur with the addition of Al

Stem Leydig cells support macrophage immunological homeostasis through mitochondrial transfer in mice

Abstract As testicular mesenchymal stromal cells, stem Leydig cells (SLCs) show great promise in the treatment of male hypogonadism. The therapeutic functions of mesenchymal stromal cells are largely determined by their reciprocal regulation by immune responses. However, the immunoregulatory properties of SLCs remain unclear. Here, we observe that SLCs transplantation restore male fertility and testosterone production in an ischemia‒reperfusion injury mouse model. SLCs prevent inflammatory cascades through mitochondrial transfer to macrophages. Reactive oxygen species (ROS) released from activated macrophages inducing mitochondrial transfer from SLCs to macrophages in a transient receptor potential cation channel subfamily member 7 (TRPM7)-mediated manner. Notably, knockdown of TRPM7 in transplanted SLCs compromised therapeutic outcomes in both testicular ischemia‒reperfusion and testicular aging mouse models. These findings reveal a new mechanism of SLCs transplantation that may contribute to preserve testis function in male patients with hypogonadism related to immune disorders

Decadal- to Centennial-Scale East Asian Summer Monsoon Variability during the Medieval Climate Anomaly Reconstructed from an Eastern Tibet Lacustrine Sequence

Instrumental data suggest changes in the intensity of the East Asian Monsoon system over the past century, possibly in response to anthropogenic climate change. To understand modern observations and explore past variations in East Asian summer monsoon (EASM) strength, we conducted grain size, geochemical, and pollen assemblage studies on a lacustrine sediment sequence from an earthquake-dammed paleolake on the eastern Tibetan Plateau. The chronology, generated from eight optically stimulated luminescence and two pollen concentrate radiocarbon dates, indicates deposition of the lacustrine sequence between 600 and 1250 C.E. Fine grain sizes and low arboreal pollen percentages are associated with regional aridity (790–916, 1020–1080, 1125–1150 C.E.) and a weak EASM, whereas coarser grain sizes and higher arboreal pollen percentages are associated with increased precipitation and a stronger EASM (1090–1125, 1160–1230 C.E.). Although observed variations in our paleodata are predominantly driven by climate, the sequence is also influenced by regional tectonics, as evident from seismites, a ~90-year hiatus (917–1004 C.E.) during a period of regional seismicity, and an abrupt increase in regional sedimentation rates. Human disturbance is also observed to increase during weak EASM intervals. On decadal to millennial scales, our paleodata are highly correlated with reconstructions of EASM strength from northeastern China and sea surface temperature reconstructions from the tropical Pacific Ocean, indicating that the Medieval Climate Anomaly was associated with a strong EASM and prolonged La Niña-like state. Our data also suggest decadal-scale EASM variability associated with solar intensity, but an inconsistent response suggests additional complexity in EASM forcing. The inverse relationship between modern EASM weakening with anthropogenic warming, and a strong EASM during the warm Medieval Climate Anomaly, suggests that the complexity of the decadal to centennial-scale EASM response may be related to changes in the mean state of the tropical Pacific Ocean