Reducing adverse impacts of Amazon hydropower expansion

Proposed hydropower dams at more than 350 sites throughout the Amazon require strategic evaluation of trade-offs between the numerous ecosystem services provided by Earth\u27s largest and most biodiverse river basin. These services are spatially variable, hence collective impacts of newly built dams depend strongly on their configuration. We use multiobjective optimization to identify portfolios of sites that simultaneously minimize impacts on river flow, river connectivity, sediment transport, fish diversity, and greenhouse gas emissions while achieving energy production goals. We find that uncoordinated, dam-by-dam hydropower expansion has resulted in forgone ecosystem service benefits. Minimizing further damage from hydropower development requires considering diverse environmental impacts across the entire basin, as well as cooperation among Amazonian nations. Our findings offer a transferable model for the evaluation of hydropower expansion in transboundary basins

Reducing greenhouse gas emissions of Amazon hydropower with strategic dam planning

Hundreds of dams have been proposed throughout the Amazon basin, one of the world’s largest untapped hydropower frontiers. While hydropower is a potentially clean source of renewable energy, some projects produce high greenhouse gas (GHG) emissions per unit electricity generated (carbon intensity). Here we show how carbon intensities of proposed Amazon upland dams (median = 39 kg CO2eq MWh−1, 100-year horizon) are often comparable with solar and wind energy, whereas some lowland dams (median = 133 kg CO2eq MWh−1) may exceed carbon intensities of fossil-fuel power plants. Based on 158 existing and 351 proposed dams, we present a multi-objective optimization framework showing that low-carbon expansion of Amazon hydropower relies on strategic planning, which is generally linked to placing dams in higher elevations and smaller streams. Ultimately, basin-scale dam planning that considers GHG emissions along with social and ecological externalities will be decisive for sustainable energy development where new hydropower is contemplated. © 2019, The Author(s)

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Ten golden rules for optimal antibiotic use in hospital settings: the WARNING call to action

Antibiotics are recognized widely for their benefits when used appropriately. However, they are often used inappropriately despite the importance of responsible use within good clinical practice. Effective antibiotic treatment is an essential component of universal healthcare, and it is a global responsibility to ensure appropriate use. Currently, pharmaceutical companies have little incentive to develop new antibiotics due to scientific, regulatory, and financial barriers, further emphasizing the importance of appropriate antibiotic use. To address this issue, the Global Alliance for Infections in Surgery established an international multidisciplinary task force of 295 experts from 115 countries with different backgrounds. The task force developed a position statement called WARNING (Worldwide Antimicrobial Resistance National/International Network Group) aimed at raising awareness of antimicrobial resistance and improving antibiotic prescribing practices worldwide. The statement outlined is 10 axioms, or “golden rules,” for the appropriate use of antibiotics that all healthcare workers should consistently adhere in clinical practice

Accuracy of the minimal leak test for endotracheal cuff pressure monitoring

Objectives To determine the accuracy of the minimum leak test as a surrogate for target endotracheal cuff pressure of 20–30 cm H2O in intubated patients. Methods Cuff pressures were measured at the University of Miami Hospital using the minimum leak test on every intubated patient once per shift, then cuff pressure was reevaluated using handheld numerical manometers and recorded pressures above or below the target range, readjusting the pressure as needed. This assessment was repeated throughout each patient's intubation for up to 6 days. The readjustment rate of the test and the probability of a patient needing at least one adjustment were determined. Results One hundred twenty‐two patients were evaluated. Median age was 67 years (range 29–95), 52% were male, 48% were female. Patients were followed for an average of 4.7 days. Seven hundred twenty‐two minimum leak tests were performed. Of these, 170 required readjustment into the target range (24% readjustment rate). Of the tests outside target range, 66% of cuffs were overinflated and 34% were underinflated. Fifty‐five percent of patients required at least one adjustment. Conclusion Despite ubiquitous use of the minimum leak test for endotracheal cuff pressure adjustment, the test has an unacceptably high error rate resulting in cuff pressures above or below the target range. Most patients will require at least one adjustment throughout an intubation, putting them at risk for tracheal injury, stenosis, or leak and aspiration. The minimum leak test is not sufficiently accurate for endotracheal cuff pressure monitoring. Formal manometry is superior and should be used to optimize patient outcomes. Level of Evidence 4 Laryngoscope, 130:1646–1650, 202

Posibilidades de la terapia antioxidante en diabetes mellitus tipo 2. Estudio del estrés oxidativo en una muestra poblacional de pacientes diabéticos

Introduction: The body exposes daily to different agents that cause normally controlled oxidative reactions. Overproduction of reactive oxygen species and/or decrease in antioxidants induce oxidative stress (OS) associated with chronic pathologies contribute to a worse prognosis of the disease. One such chronic pathology is diabetes mellitus (DM) in which OS has shown to be highly involved in its pathophysiology and as part of the development of complications. The OS index (OSI) was determined in individuals with DM and in a healthy control group, to assess their possible correlation and degree of oxidative damage, as an initial supportive strategy for a potential antioxidant therapy as an adjunction to conventional treatment Methods: OSI was measured in a population of 110 individuals with DM, consisting of 37 cases of type 1 DM (DMT1) and 73 type 2 (DMT2) at ages between 50 and 70 years chosen at random and compared with the values of a healthy volunteer control group. The main goal of the clinical trial was to define the degree of correlation between OSI levels and oxidative damage severity, weighted from a qualitative formula, through the measurement of nine OS biomarkers in erythrocyte lysate. Discussion: The prevention or detention of DM comorbidities may rest in the future in the precise identification of biomarkers and their regulatory counterpart. The inclusion of a therapy using an antioxidant protocol adjuvant to the standard management of DMT2 could provide more effective results for hyperglycemic control and, therefore, to induce redox balance. The results show that this type of therapy would not be effective in DMT1. The recognition of the extent and type of oxidative damage in specific populations is decisive, through the creation and use of a baseline with the most frequently altered biomarkers. This baseline will help defining the best antioxidant strategy to be applied, because genetic polymorphism, the environment and styles of life act specifically in the type of response to the OS. A beneficial scheme to assess may be the development of new drugs with antioxidant effects or products capable of strengthening the physiological antioxidant system made from natural substrates and the making of effective fixed dose combinations of antioxidants that attack the causes of OS in DM. The final aim is to reverse oxidative damage in order to prevent the appearance of complications or slow them down. Conclusions: The use of OSI with different biomarkers helps to achieve the specificity of OS diagnosis, but for the choice of markers to be correct, these must be defined by the objective and design of the study, as well as by the clinical relevance in the selected subjects, as was the one applied in the actual trial. The results obtained demonstrate the potentiality of the use of antioxidant therapy in DMT2, but not in DMT1. The clinical importance of OS biomarkers in humans should come from a critical marker’s analysis that reflects the overall status of redox under particular conditions and guidance for effective antioxidant therapyIntroducción: el organismo se expone cotidianamente a diferentes agentes que provocan reacciones oxidativas normalmente controladas. La sobreproducción de especies reactivas del oxígeno y/o la deficiencia de antioxidantes lleva al estrés oxidativo (EO) asociado a patologías crónicas que contribuye a un peor pronóstico de las enfermedades. Una de esas patologías crónicas es la diabetes mellitus (DM), en la que se ha demostrado una gran participación del EO en su fisiopatología y en el desarrollo de complicaciones. Se determinó el índice de EO (IEO) en individuos con DM y en un grupo sano control, para evaluar su posible correlación y grado de daño oxidativo, como estrategia para justificar una intervención potencial con una terapia antioxidante adyuvante al tratamiento convencional. Materiales y métodos: se midió IEO en una población de 110 individuos con DM, constituida por 37 casos de DM tipo 1 (DMT1) y 73 del tipo 2 (DMT2) en edades entre 50 y 70 años escogidos al azar y se comparó con los valores de un grupo control de voluntarios sanos. El objetivo del ensayo clínico fue definir el grado de correlación entre los niveles del IEO y la severidad del daño oxidativo, ponderado a partir de una fórmula cualitativa, a través de la medición de nueve biomarcadores del EO en lisados de eritrocitos. Discusión: la prevención o la detención de las comorbilidades de la DM puede que descanse en el futuro en la identificación precisa de los biomarcadores y su contrapartida reguladora. La incorporación de una terapia utilizando un protocolo con antioxidantes (AO) adyuvantes al manejo estándar de la DMT2 podría proveer resultados más eficaces para el control hiperglucémico y, por tanto, para inducir el equilibrio redox. Los resultados demuestran que ese tipo de terapia no sería eficaz en DMT1. Es determinante el reconocimiento de la extensión y tipo de daño oxidativo de las poblaciones específicas, mediante la creación y utilización de una línea de base con los biomarcadores alterados más frecuentemente. Esta línea de base ayudará a definir la mejor estrategia antioxidante a aplicar, porque el polimorfismo genético, el ambiente y los hábitos de vida actúan puntualmente en el tipo respuesta al EO. Una estrategia beneficiosa a valorar puede ser la del desarrollo de nuevos fármacos con efectos antioxidantes o de productos capaces de reforzar el sistema fisiológico de antioxidación a partir de sustratos naturales y la elaboración de combinaciones de dosis fijas de AO eficaces que ataquen las causas el EO en la DM. El objetivo final será el de revertir el daño oxidativo para prevenir la instalación de complicaciones o frenarlas. Conclusiones: el uso del IEO con distintos marcadores ayuda a la especificidad del diagnóstico del EO, pero para que la elección de los marcadores sea la correcta, esta debe estar definida por el objetivo y el diseño del estudio, así como por la relevancia clínica en los sujetos seleccionados, tal cual fue el aplicado en el ensayo realizado. Los resultados obtenidos demuestran la potencialidad del uso de la terapia antioxidante en DMT2, pero no así en la DMT1. La importancia clínica de los biomarcadores del EO en humanos debe provenir de un análisis crítico de los marcadores que refleje el estado general de redox en condiciones particulares y una orientación para una terapia antioxidante efectiva