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The use of renewable energy sources has become strategic in the production of electricity worldwide due to global efforts to increase energy efficiency and achieve a net zero carbon footprint. Hybrid systems can maximize stability and reduce costs by combining multiple energy sources. A conventional metric, such as the levelized cost of energy (LCOE), that is appropriate for assessing the cost-effectiveness of an option may not be appropriate when evaluating the economic feasibility of hybrid systems. This study proposes a stochastic discounted cash flow model (DCF) to assess the economic viability of a hybrid renewable energy system (HRES) in Brazil. The objective is to determine the combinations that will provide the highest 50th percentile internal rate of return (IRR) and the lowest coefficient of variation (CV). Model variables include capital expenditures (CAPEX), operation and maintenance (O&M) costs, sectoral charges, taxes, and long-term energy production metrics. The results demonstrate that the synergies modeled contributed to the higher economic outcomes for the HRES obtained by combining both energy sources rather than opting for a stand-alone configuration. A wind-dominant combination of 60% wind was able to increase the 50th percentile of the IRR, while a solar-dominant combination of 65% solar minimized the CV. [ABSTRACT FROM AUTHOR]

The knowledge on the deposition and retention of the viral particle of SARS-CoV-2 in the respiratory tract during the very initial intake from the ambient air is of prime importance to understand the infectious process and COVID-19 initial symptoms. We propose to use a modified version of a widely tested lung deposition model developed by the ICRP, in the context of the ICRP Publication 66, that provides deposition patterns of microparticles in different lung compartments. In the model, we mimicked the "environmental decay" of the virus, determined by controlled experiments related to normal speeches, by the radionuclide 11C that presents comparable decay rates. Our results confirm clinical observations on the high virus retentions observed in the extrathoracic region and the lesser fraction on the alveolar section (in the order of 5), which may shed light on physiopathology of clinical events as well on the minimal inoculum required to establish infection. [ABSTRACT FROM AUTHOR]

The "Sick Building Syndrome" is a term used to define the poor quality of indoor air environments and has been of growing concern in the scientific community. The assessment of air quality in the places sampled in HUPE, based on Resolution No. 9 of 2003 of the National Health Surveillance Agency, aims to identify and report to the Hospital Infection Control Commission to assess the interaction of this factor with the nosocomial infections and the need to decide whether or not corrective measures and contribute to the knowledge and development techniques and pollution control "Indoor". The samples were collected with an air linear impactor type sampler, a stage (MERCK) and the interpretation of results used two criteria contained in current legislation: the maximum acceptable value (VMA) of fungi in indoor environments (750 UFC/m³) and the acceptable limit between the internal and external contamination (I/E ≤ 1.5). Among the sixty locations evaluated in the first three floors of HUPE 20% of the total were in disagreement about the number of CFU/m³ and 16.6% compared to I/E ratio. It was concluded that 28% of the evaluated sectors of the 1st HUPE the floor and 26% from those in the 2nd floor are not having the desired air change, leading to the accumulation of fungi. [ABSTRACT FROM AUTHOR]

The article focuses on taking a transdisciplinary approach to transgender health care and setting up an outpatient unit for transgender health by discussing a study at Universidade Federal de Sao Paulo, Brazil. Topics discussed include the benefits of exchanges between health professionals and transgender community, the use of role-playing technique in training sessions, and the recommendations by the study for implementing a transgender health care program.