Gluino production in ultrarelativistic heavy ion collisions and nuclear shadowing

In this article we investigate the influence of nuclear effects in the production of gluinos in nuclear collisions at the LHC, and estimate the transverse momentum dependence of the nuclear ratios $R_{pA} = {\frac{d\sigma (pA)}{dy d^2 p_T}} / A {\frac{d\sigma (pp)}{dy d^2 p_T}}$ and $R_{AA} = {\frac{d\sigma (AA)}{dy d^2 p_T}} / A^2 {\frac{d\sigma (pp)}{dy d^2 p_T}}$. We demonstrate that depending on the magnitude of the nuclear effects, the production of gluinos could be enhanced, compared to proton-proton collisions. The study of these observables can be useful to determine the magnitude of the shadowing and antishadowing effects in the nuclear gluon distribution. Moreover, we test different SPS scenarios, corresponding to different soft SUSY breaking mechanisms, and find that the nuclear ratios are strongly dependent on that choice.Comment: 7 pages, 5 figures; results and discussions changed/added. Accepted for publication in Physical Review

Revealing the beneficial effects of Ge doping on Cu2ZnSnSe4 thin film solar cells

Kesterite (CZTSe) is a promising thin film photovoltaic absorber material due to its composition of more earth abundant materials compared to mature thin film photovoltaic technologies. Up to now, power conversion efficiencies are still lower and its main problem is the low open circuit voltage (Voc). Recently, a novel sintering approach using a nanometric Ge layer showed a large increase in device performance and especially in Voc. In this work, in-depth solar cell characterization as well as Raman and Photoluminescence studies of devices employing different Ge doped CZTSe absorber layers is presented. The main focus is to reveal the beneficial effects of Ge doping and furthermore investigate the interaction of Ge and Na. For low Ge doping an increase in charge carrier concentration is observed, resulting in devices with Voc of 460 mV, which corresponds to Voc deficits (Eg/q–Voc) of 596 mV a value comparable to current record devices. For high Ge amounts admittance spectroscopy measurements identified the appearance of a deep defect which can explain the observed deterioration of solar cell performance. Additional Na provided during crystallization of high Ge doped devices can reduce the density of this deep defect and recover device performance. These results indicate that Na plays an important role in defect passivation and we propose a defect model based in the interaction of group IV elements and Na with Cu vacancies

A planetary boundaries perspective on the sustainability:resilience relationship in the Kenyan tea supply chain

The purpose of this paper is to examine whether agricultural supply chains (ASC) can be simultaneously sustainable and resilient to ecological disruptions, using the Planetary Boundaries theory. The nine different Planetary Boundaries i.e. climatic change, biodiversity loss, biogeochemical, ocean acidification, land use, freshwater availability, stratosphere ozone depletion, atmospheric aerosols and chemical pollution are examined in relation to ASC sustainability and resilience. Kenya's tea upstream supply chain sustainability and resilience from the ecological point of view is questioned. This study adopts a multi-case study analysis approach of nine producer organisations from Kenya's tea supply chain. The data from the in-depth semi-structured interviews and a focus group discussion are analysed using thematic analysis. The Kenyan tea supply chain producers are not aware of all the nine planetary boundaries, although these impact on their resilience practices. They are engaged in pursuing both sustainability and resilience practices. They implement mainly environmental practices in relation to sustainability, while only a few of them are implementing resilience practices. The sustainability and resilience concepts were found to be interrelated, but resilience does not improve at the same pace as sustainability. It is suggested that the relationship between sustainability and resilience is non-linear. Limitations and future research avenues are also provided

Resonant Raman scattering of ZnS_xSe_1-x solid solutions:role of S and Se electronic states

A combined theoretical and experimental study of the enhancement in the Raman mode intensities of ZnSSe compounds, under various resonant conditions, is presented, leading to more detailed insights into the role of chalcogen electronic states in the photon–matter interaction.</p

Multiwavelength excitation Raman scattering analysis of bulk and 2 dimensional MoS2: vibrational properties of atomically thin MoS2 layers

In order to deepen the knowledge of the vibrational properties of two-dimensional (2D) MoS2 atomic layers, a complete and systematic Raman scattering analysis has been performed using both bulk single-crystal MoS2 samples and atomically thin MoS2 layers. Raman spectra have been measured under non-resonant and resonant conditions using seven different excitation wavelengths from near-infrared (NIR) to ultraviolet (UV). These measurements have allowed us to observe and identify 41 peaks, among which 22 have not been previously experimentally observed for this compound, and characterize the existence of different resonant excitation conditions for the different excitation wavelengths. This has also included the first analysis of resonant Raman spectra that are achieved using UV excitation conditions. In addition, the analysis of atomically thin MoS2 layers has corroborated the higher potential of UV resonant Raman scattering measurements for the non-destructive assessment of 2D MoS2 samples. Analysis of the relative integral intensity of the additional first- and second-order peaks measured under UV resonant excitation conditions is proposed for the non-destructive characterization of the thickness of the layers, complementing previous studies based on the changes of the peak frequencies

Knowledge and practices of community health agents in mental health demands - Conhecimentos e práticas de Agentes Comunitários de Saúde frentes às demandas de saúde mental

Objective: to identify knowledge and practices by Community Health Agents in the face of mental health demands in Primary Care. Method: qualitative exploratory study, carried out in a municipality on the West Frontier of Rio Grande do Sul. Data collection took place between October and November 2022, through semi-structured interviews,&nbsp; content analysis. The study included 12 Community Health Agents working in three Family Health Strategies. Results: the biomedical paradigm is present in the daily practices of the interviewed professionals. The care provided to people in psychological distress and their families is limited due to the Agents' lack of knowledge. Final Considerations: the importance of Continuing and Continuous Education activities with Community Agents is highlighted, in order to improve the quality of care, increase the scope of mental health actions in the territory and reduce exclusionary and stigmatizing practices.Objetivo: identificar saberes y prácticas de Agentes Comunitarios de Salud frente a las demandas de salud mental en la Atención Primaria. Método: estudio exploratorio cualitativo, realizado en un municipio de la Frontera Oeste de Rio Grande do Sul. La recolección de datos ocurrió entre octubre y noviembre de 2022, a través de entrevistas semiestructuradas, tratadas por Análisis de contenido. El estudio contó con 12 Agentes Comunitarios de Salud actuando en tres Estrategias de Salud de la Familia. Resultados: el paradigma biomédico está presente en las prácticas cotidianas de los profesionales entrevistados. La atención que se brinda a las personas con malestar psíquico y sus familias es limitada debido al desconocimiento de los Agentes. Consideraciones finales: se destaca la importancia de las actividades de Educación Continua y Continua con Agentes Comunitarios, con el fin de mejorar la calidad de la atención, ampliar el alcance de las acciones de salud mental en el territorio y reducir las prácticas excluyentes y estigmatizantes.Objetivo: identificar conhecimentos e práticas de Agentes Comunitários de Saúde frente às demandas de saúde mental na Atenção Básica. Método: estudo qualitativo de caráter exploratório, realizado em um município da Fronteira Oeste do Rio Grande do Sul. A coleta de dados ocorreu entre outubro e novembro de 2022, através de entrevistas semiestruturadas, tratadas por Análise de Conteúdo. Participaram do estudo 12 Agentes Comunitários de Saúde atuantes em três Estratégias Saúde da Família. Resultados: o paradigma biomédico está presente no cotidiano das práticas dos profissionais entrevistados. O cuidado prestado às pessoas em sofrimento psíquico e suas famílias é limitado devido a falta de conhecimento dos Agentes. Considerações Finais: destaca-se a importância de atividades de Educação Permanente e continuada junto aos Agentes Comunitários, a fim de melhorar a qualidade do cuidado, aumentar a abrangência das ações de saúde mental no território e reduzir práticas excludentes e estigmatizantes.

The importance of back contact modification in Cu2ZnSnSe4 solar cells: The role of a thin MoO2 layer

Cu2ZnSn(SxSe1−x)4 (CZTSSe) photovoltaic absorbers could be the earth-abundant and low toxicity replacement for the already commercialized CuIn1−xGaxSe2 (CIGS) thin film technology. In order to make this possible, specific research efforts applied to the bulk, front and back interfaces must be performed with the aim of improving CZTSSe performance. In this paper the importance of back contact modification to obtain high efficiency Cu2ZnSnSe4 (CZTSe) solar cells and to increase a paramount and limiting parameter such as VOC is highlighted. Several Mo configurations (monolayer, bi-layer and tri-layer) with different electrical and morphological properties are investigated in CZTSe solar cells. An optimum tri-layer configuration in order to minimize overselenization of the back contact during thermal annealing while keeping reasonable electrical features is defined. Additionally, a thin intermediate MoO2 layer that results in a very effective barrier against selenization and innovative way to efficiently assist in the CZTSe absorber sintering is introduced. The use of this layer enhances grain growth and subsequently the efficiency of solar cells increases via major VOC and FF improvement. An efficiency increase from 7.2% to 9.5% is obtained using a Mo tri-layer with a 20nm intermediate MoO2 layer

La vid silvestre en México. Actualidades y potencial

En ocho capítulos se aborda el estado del arte de la vid silvestre en MéxicoEl estudio de las especies vegetales nativas de México representa un reto que cada día más investigadores mexicanos asumen. Durante muchos años, el apoyo a la investigación pública ha sido mínimo; desde el punto de vista agronómico es insuficiente para avanzar a la velocidad que requiere nuestro país para afrontar problemas de producción y distribución de alimentos. Por esa razón, entre otras, me es grato presentar esta obra que compila parte de los trabajos de la Red de Vid Silvestre patrocinada por el Sistema Nacional de Recursos Fitogenéticos (sinarefi) dependiente de la sagarpa; trabajos apuntalados por investigadores que sin pertenecer a la red han colaborado en el estudio de las plantas del género Vitis. En este libro se muestra el potencial del país para aprovechar el recurso vid, empleado desde antes de la conquista española por nativos mexicanos que conocían sus bondades. Es necesario continuar el avance en el conocimiento de este recurso, por ello el presente libro pretende invitar a toda persona interesada en contribuir con el rescate y conservación de las vides mexicanas. Los autores y editores, así como las instituciones en donde laboramos y aquellas que patrocinan estas investigaciones, esperamos se cumpla este objetivo y que el lector, alumno, profesor, investigador, público en general, disfrute esta lectura y, sobre todo, se interese en el recurso VitisSEP, SINAREFI, UAEME