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Abstract: The herpes simplex virus type 2 (HSV-2) is a sexually transmitted infection prevalent in the world; in spite of despite diagnostic and therapeutic advances. According to estimates in 2012, it was calculated that there were 417 million people infected worldwide. The objective of this project was to detect HSV-2 in indigenous women of the Zulia state, for that 100 women of the Wayúu and Añú ethnic groups, were selected without discriminating age and/or parity. The physician proceeded to sample with an alginate swab, for the processing of the same was used the polymerase chain reaction (PCR) method to detect HSV-2 in samples of cervical-uterine origin, and cytological diagnosis was made through staining with hematoxylin-eosin. 22% of HSV-2 positive samples were obtained, the results show that a considerable percentage of patients present HSV-2 infection, which is extremely important because it can contribute to the progression of processes inflammatory agents. Resumen: El virus herpes simple tipo 2 (VHS-2), es una infección de transmisión sexual prevalente en el mundo a pesar de los avances diagnósticos y terapéuticos. Según estimaciones en el 2012, se calculaba que existían 417 millones de personas infectadas en todo el mundo. El objetivo de este proyecto fue detectar el VHS-2 en mujeres indígenas del estado Zulia, para ello se seleccionaron 100 mujeres de las etnias wayúu y añú sin discriminar edad y/o paridad. El médico procedió a realizar la toma de muestras con un hisopo de alginato, para el procesamiento de las mismas se utilizó el método de Reacción en Cadena de la Polimerasa (PCR) para detectar el VHS-2, en muestras de origen cérvico-uterino, y el diagnostico citológico se realizó a través de la coloración con hematoxilina- eosina. Se obtuvo un 22% de muestras positivas para VHS-2, los hallazgos obtenidos, demuestran que un porcentaje considerable de las pacientes presentan infección por el VHS- 2, siendo este de suma importancia debido a que el mismo puede contribuir a la progresión de procesos inflamatorios persistentes.

Abstract: To determine the prevalence of intestinal parasites, rotavirus and adenovirus in apparently healthy children, a parasitological study of 101 fecal samples from persons between 2 months and 14 years from both sexes was performed, as well as a virological study of 70 samples of less than 5 years of age. For each fecal specimen, a direct coproparasitological examination was performed, with Formol – Ether concentration and Modified Zielh-Nielsen tincture techniques was made. To determine the Rotavirus and Adenovirus, the immunoenzymatic assay technique (ELISA) was used. The Ji-square (c2) and the Z test were used for statistical analysis. A high percentage of people with parasites was found (85.15%). The most frequent protozoan species were: Blastocystis hominis (52.47%), Giardia lamblia (26.73.%) and Entamoeba coli (20.79%); among the helminthes were Trichuris trichiura (50.49%), Ascaris lumbricoides (48.51%) and Strongyloides stercoralis (7.92%). Rotavirus frequency was 2.86%, while Adenovirus infection was absent. The high prevalence of parasites demonstrates unhealthy conditions in the community; despite these, the opposite occurred regarding the virus being studied. Perhaps the acquisition of antibodies through maternal lactation influenced the Rotovirus percentages, whereas development of antibodies at an early age probably influenced the enteric Adenovirus. Resumen: Para determinar la prevalencia de parásitos intestinales, rotavirus y adenovirus en niños aparentemente sanos, se realizó el estudio parasitológico de 101 muestras fecales de individuos de uno u otro sexo, con edades comprendidas entre 2 meses y 14 años, así como el estudio virológico en 70 muestras de los niños menores de 5 años. A cada espécimen fecal se le realizó un examen coproparasitológico directo, concentración de Formol-Éter y coloración de Kinyoun. Para determinar Rotavirus y Adenovirus se empleó la técnica de Ensayo Inmunoenzimático (ELISA). Para el análisis estadístico se utilizó el Ji-cuadrado (x2) y la prueba Z. Se observó un elevado porcentaje de individuos parasitados (85,15%), los protozoarios más frecuentes fueron: Blastocystis hominis (52,47%), Giardia lamblia (26,73%) y Entamoeba coli (20,79%) y entre los helmintos Trichuris trichiura (50,49%), Ascaris lumbricoides (48,51%) y Strongyloides stercoralis (7,92%). Se observó una frecuencia de Rotavirus del 2,86% y ausencia de infección por Adenovirus. La elevada prevalencia parasitaria demuestra las condiciones de insalubridad de la comunidad, a pesar de ello, lo contrario ocurrió con los virus estudiados. Para Rotavirus quizás influyó la adquisición de anticuerpos a través de la lactancia materna, mientras que, para Adenovirus entéricos, probablemente el desarrollo de anticuerpos a edad temprana.

This paper implements a framework that catalogs and maps opportunities at a city level to support the electrification of the transportation system in an equitable way. Leveraging on the use of hyper-local air quality data, paired with sociodemographic indicators, we evaluate the framework in the City of Oakland, CA under a context of public and private transport areas to prioritize interventions and incentives, while reducing environmental hazard exposure under an equity focus. Following the recognition of racial and socio-economic disparities, the subsequent steps of implementing operational strategies are to identify specific bus routes in the city in which decarbonization would render the highest impact with respect to the distribution of environmental burden, and to identify regions in which private vehicle interventions would render the highest impact with respect to racial and social equity and mobility.

As global political discourse is taking place where the need for a cleaner energy mix is constantly highlighted, manufacturing strategies are becoming more relevant. Thus, the photovoltaics system design is a crucial aspect related with the overall sustainability. In fact, various countries are considering the potential to locally manufacture different elements of the photovoltaics (PV) value chain and the strategies to incentivize a local manufacturing base. This paper develops a mathematical programming approach for the optimal design of a PV manufacturing value chain considering diverse criteria linked to economic and environmental performance such as minimum sustainable price, transportation capacity, among others, and considering uncertainty. In addition, the proposed methodology involves the dependence over time of supply chain variables and economic parameters such as inflation, electricity cost, and weighted average cost of capital, to determine the manufacturing system topology under uncertain conditions. Our results highlight the importance of planning models to develop markets policies related to supply chains, production level changes and imposed tariffs all while involving uncertainty in economic parameters, which is an improvement compared to planning models that use deterministic formulations. Finally, the proposed methodology and results can encourage decision-making considering probable variations in different parameters.

The rooftop solar industry in the United States has experienced dramatic growth—roughly 50% per year since 2012, along with steadily falling prices. Although the opportunities this affords for clean, reliable power are transformative, the benefits might not accrue to all individuals and communities. Combining the location of existing and potential sites for rooftop photovoltaics (PV) from Google’s Project Sunroof and demographic information from the American Community Survey, the relative adoption of rooftop PV is compared across census tracts grouped by racial and ethnic majority. Black- and Hispanic-majority census tracts show on average significantly less rooftop PV installed. This disparity is often attributed to racial and ethnic differences in household income and home ownership. In this study, significant racial disparity remains even after we account for these differences. For the same median household income, black- and Hispanic-majority census tracts have installed less rooftop PV compared with no majority tracts by 69 and 30%, respectively, while white-majority census tracts have installed 21% more. When correcting for home ownership, black- and Hispanic-majority census tracts have installed less rooftop PV compared with no majority tracts by 61 and 45%, respectively, while white-majority census tracts have installed 37% more. The social dispersion effect is also considered. This Analysis reveals the racial and ethnic injustice in rooftop solar participation.

Renewable energy is often presented as a partisan issue. However, solar incentives have made rooftop PV attractive to many consumers, regardless of political affiliation. This paper quantifies the role of political affiliation in rooftop PV adoption for the Democratic-leaning state of New York and Republican-leaning state of Texas. High resolution rooftop PV installation data from Google Project Sunroof is combined with election data from the Harvard Election Data Archive. We applied a bootstrapped LOWESS model to fit local linear relationships between rooftop PV adoption and both voting behavior and household income. In doing so, we find that Republican-majority communities are installing rooftop PV at equal or greater rates than Democraticmajority communities. While Republican politicians may be less likely than Democrats to support renewable energy, this partisan division is not found at the voter level.

We present a framework (TIT-4-TAT) that enables the study of manufacturing strategies by coupling a technoeconomic model with tariff and transportation algorithms to optimize supply chain layouts for PV manufacturing. We use this framework in a scenario where Mexico, China, USA, and Brazil interact under two tariffs scenarios. The optimal manufacturing locations due to tariff levels variations are highlighted through this approach.

After undergoing an unprecedented energy reform, Mexico is poised to significantly grow its renewable energy share, and evolve from 80 MW installed solar photovoltaics (PV) capacity in 2015, to more than 6 GW by 2022. The impact on the overall electrical grid is therefore a crucial element to determine where the investments should be allocated -both in generation, and transmission-, to be optimally deployed. In this contribution, we model the generation, transmission and distribution assets in Mexico and optimize the investment in capacity to meet policy goals under three different plausible scenarios.

Solar photovoltaics (PV) manufacturing has experienced dramatic worldwide growth in recent years, enabling a reduction in module costs, and a higher adoption of these technologies. Continued sustainable price reductions, however, require strategies focused in further technological innovation, minimization of capital expenditures, and optimization of supply chain flows. We present a framework: Techno-economic Integrated Tool For Tariff And Transportation (TIT-4-TAT), that enables the study of these different strategies by coupling a techno-economic model with a tariff and transportation algorithm to optimize supply chain layouts for PV manufacturing under equally-weighted objectives. We demonstrate the use of this framework in a set of interacting countries (Mexico, China, USA, and Brazil) and two extreme tariff scenarios: no tariffs, and high tariff levels imposed. Results indicate that introducing tariffs between countries significantly increase the minimum sustainable price for solar PV manufacturing, alter the optimal manufacturing locations, and render a more expensive final solar PV module price which can hinder the adoption rates required to mitigate climate change. Recommendations for stakeholders on the optimization process, and techno-economic drivers are presented based on our results. This framework may be utilized by policymakers for the spatially-resolved planning of incentives, labor and manufacturing programs, and proper import tariff designs in the solar PV market.

Distributed photovoltaics (PV) have played a critical role in the deployment of solar energy, currently making up roughly half of the global PV installed capacity. However, there remains significant unused economically beneficial potential. Estimates of the total technical potential for rooftop PV systems in the United States calculate a generation comparable to approximately 40% of the 2016 total national electric-sector sales. To best take advantage of the rooftop PV potential, effective analytic tools that support deployment strategies and aggressive local, state, and national policies to reduce the soft cost of solar energy are vital. A key step is the low-cost automation of data analysis and business case presentation for structure-integrated solar energy. In this paper, the scalability and resolution of various methods to assess the urban rooftop PV potential are compared, concluding with suggestions for future work in bridging methodologies to better assist policy makers.

The bulk minority-carrier lifetime in p- and n-type kerfless epitaxial (epi) crystalline silicon wafers is shown to increase >500x during phosphorus gettering. We employ kinetic defect simulations and microstructural characterization techniques to elucidate the root cause of this exceptional gettering response. Simulations and deep-level transient spectroscopy (DLTS) indicate that a high concentration of point defects (likely Pt) is "locked in" during fast (60 °C/min) cooling during epi wafer growth. The fine dispersion of moderately fast-diffusing recombination-active point defects limits as-grown lifetime but can also be removed during gettering, confirmed by DLTS measurements. Synchrotron-based X-ray fluorescence microscopy indicates metal agglomerates at structural defects, yet the structural defect density is sufficiently low to enable high lifetimes. Consequently, after phosphorus diffusion gettering, epi silicon exhibits a higher lifetime than materials with similar bulk impurity contents but higher densities of structural defects, including multicrystalline ingot and ribbon silicon materials. Device simulations suggest a solar-cell efficiency potential of this material >23%. [ABSTRACT FROM AUTHOR]

Dislocation clusters in multicrystalline silicon limit solar cell performance by decreasing minority carrier diffusion length. Studies have shown that the recombination strength of dislocation clusters can vary by up to two orders of magnitude, even within the same wafer. In this contribution, we combine a surface-analysis approach with bulk characterization techniques to explore the underlying root cause of variations in recombination strength among different clusters. We observe that dislocation clusters with higher recombination strength consist of dislocations with a larger variation of line vector, correlated with a higher degree of variation in dislocation etch-pit shapes (ellipticities). Conversely, dislocation clusters exhibiting the lowest recombination strength contain mostly dislocations with identical line vectors, resulting in very similar etch-pit shapes. The disorder of dislocation line vector in high-recombination clusters appears to be correlated with impurity decoration, possibly the cause of the enhanced recombination activity. Based on our observations, we conclude that the relative recombination activity of different dislocation clusters in the device may be predicted via an optical inspection of the distribution and shape variation of dislocation etch pits in the as-grown wafer. [ABSTRACT FROM AUTHOR]