1,800 research outputs found

    Sanitización de biosólidos de plantas de tratamiento primario avanzado: ¿compostaje o estabilización alcalina?

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    Este estudio tuvo como propósito evaluar dos alternativas de reducción de patógenos; Compostaje y tratamiento alcalino en los biosólidos generados en la Planta de Tratamiento de Aguas Residuales de Cañaveralejo (PTAR-C), de Cali, Colombia. Para el compostaje se utilizó: Biosólidos; Biosólidos (B) + cachaza (C)+ residuos de poda (P); Biosolido (B) + Residuos Organicos de mercado (ROPM) + residuos de poda (P), por 61 días. El tratamiento alcalino se desarrollo por 13 días. Cal apagada y ceniza de carbón fue aplicada a: Biosólidos y al producto final del compostaje. Fueron 8, 15 y 30 % (peso/peso) las concentraciones aplicadas de ambos tipos de alcalinizantes. pH, humedad, temperatura, demanda química de Oxigeno (DQO, Nitrogeno Total Kjeldahl (NTK), Nitrogeno amoniacal (N- NH , huevos de helmintos y coliformes fecales (CF) se 4) monitorearon en ambos experimentos. Los resultados mostraron que la mejor mezcla de compost fue (B + C + P), eliminado patógenos, manteniendo la clasificación del material como Clase B, con una media geométrica para CF de 4x10-3 UFC g-1, indicando que el proceso no alcanza la clase A. La estabilización alcalina mostró que la ceniza para todas las dosis aplicadas produjo una calidad microbiológica de CF similar al compost, mostrando cierta debilidad de este material en su poder higienizante desde el punto de vista costo-eficiencia. Cal apagada al 15 y 30% produjo mejor calidad microbiológica con cero UFC g-1 de CF, alcanzando el estándar de clase A según la Agencia de Proteccion Ambiental. Esta situación puede estar asociada al incremento de pH. Para el 8% (peso/peso) la calidad fue menor a las dos anteriores y no alcanzó el estándar de clase A

    The actin-microtubule cross-linking activity of Drosophila Short stop is regulated by intramolecular inhibition

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    Actin and microtubule dynamics must be precisely coordinated during cell migration, mitosis, and morphogenesis—much of this coordination is mediated by proteins that physically bridge the two cytoskeletal networks. We have investigated the regulation of the Drosophila actin-microtubule cross-linker Short stop (Shot), a member of the spectraplakin family. Our data suggest that Shot's cytoskeletal cross-linking activity is regulated by an intramolecular inhibitory mechanism. In its inactive conformation, Shot adopts a “closed” conformation through interactions between its NH2-terminal actin-binding domain and COOH-terminal EF-hand-GAS2 domain. This inactive conformation is targeted to the growing microtubule plus end by EB1. On activation, Shot binds along the microtubule through its COOH-terminal GAS2 domain and binds to actin with its NH2-terminal tandem CH domains. We propose that this mechanism allows Shot to rapidly cross-link dynamic microtubules in response to localized activating signals at the cell cortex

    High-Frequency Oscillatory Ventilation Use and Severe Pediatric ARDS in the Pediatric Hematopoietic Cell Transplant Recipient

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    INTRODUCTION: The effectiveness of high-frequency oscillatory ventilation (HFOV) in the pediatric hematopoietic cell transplant patient has not been established. We sought to identify current practice patterns of HFOV, investigate parameters during HFOV and their association with mortality, and compare the use of HFOV to conventional mechanical ventilation in severe pediatric ARDS. METHODS: This is a retrospective analysis of a multi-center database of pediatric and young adult allogeneic hematopoietic cell transplant subjects requiring invasive mechanical ventilation for critical illness from 2009 through 2014. Twelve United States pediatric centers contributed data. Continuous variables were compared using a Wilcoxon rank-sum test or a Kruskal-Wallis analysis. For categorical variables, univariate analysis with logistic regression was performed. RESULTS: The database contains 222 patients, of which 85 subjects were managed with HFOV. Of this HFOV cohort, the overall pediatric ICU survival was 23.5% (n = 20). HFOV survivors were transitioned to HFOV at a lower oxygenation index than nonsurvivors (25.6, interquartile range 21.1-36.8, vs 37.2, interquartile range 26.5-52.2, P = .046). Survivors were transitioned to HFOV earlier in the course of mechanical ventilation, (day 0 vs day 2, P = .002). No subject survived who was transitioned to HFOV after 1 week of invasive mechanical ventilation. We compared subjects with severe pediatric ARDS treated only with conventional mechanical ventilation versus early HFOV (within 2 d of invasive mechanical ventilation) versus late HFOV. There was a trend toward difference in survival (conventional mechanical ventilation 24%, early HFOV 30%, and late HFOV 9%, P = .08). CONCLUSIONS: In this large database of pediatric allogeneic hematopoietic cell transplant subjects who had acute respiratory failure requiring invasive mechanical ventilation for critical illness with severe pediatric ARDS, early use of HFOV was associated with improved survival compared to late implementation of HFOV, and the subjects had outcomes similar to those treated only with conventional mechanical ventilation

    2023 Roadmap on ammonia as a carbon-free fuel

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    The 15 short chapters that form this 2023 ammonia-for-energy roadmap provide a comprehensive assessment of the current worldwide ammonia landscape and the future opportunities and associated challenges facing the use of ammonia, not only in the part that it can play in terms of the future displacement of fossil-fuel reserves towards massive, long-term, carbon-free energy storage and heat and power provision, but also in its broader holistic impacts that touch all three components of the future global food-water-energy nexus

    New genetic loci link adipose and insulin biology to body fat distribution.

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    Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

    Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity.

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    Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant
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