15 research outputs found

    Reúso de aguas residuales: impacto en los atributos químicos y macronutricionales en un suelo inceptisol irrigado con aguas residuales domésticas tratadas

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    (Eng) This study aimed to estimate the potential impact of wastewater reuse on the chemical and macronutritional attributes of an inceptisol cropped with sugarcane. The experimental design was in three randomized blocks, in split-plot design (three replicates per treatment), with three different irrigation treatments: treated wastewater (TWW) from Cañaveralejo wastewater treatment plant (WWTP-C); groundwater without any fertilizer (GW); and groundwater with chemical fertilizer (GW+CF). At the end of the study, plots with treated wastewater irrigation improved slightly Ca/Mg, Mg/K, and Ca+Mg/K ratios, increased OM, Na, P, and K contents and decreased pronouncedly inorganic nitrogen (N-NH4, N-NO3) of an inceptisol. Besides, we found that the type of treatment did not influence the variation of chemical attributes in soil, since statistically differences were no found in comparison among treatments. Therefore, our results suggest no adverse impact on chemical soil attributes due to wastewater reuse on sugarcane irrigation.(Spa) Este estudio tuvo como objetivo estimar el potencial impacto en los atributos químicos y macronutricionales de un suelo inceptisol sembrado con caña de azúcar y sometido a tres diferentes tratamientos de riego: Efluente de la PTAR-C (T1), Agua de Pozo (T2) y Agua de Pozo más fertilización química (T3). Se instaló un experimento en bloques completos al alzar con parcelas divididas con tres repeticiones. Al final del estudio se encontró que las relaciones de bases químicas (Ca/Mg, Mg/K, Ca+Mg/K) mejoraron en todas las parcelas, en todos los tratamientos, situación que se ratifica al no encontrarse diferencias estadísticas significativas entre los tratamientos. Así mismo, se encontró que el tipo de tratamiento no influyó en la variación en los contenidos de los macronutrientes (N, P, K) del suelo. Los contenidos de materia orgánica, P, Na y K aumentaron; y disminuyeron los de nitrógeno inorgánico (N-NH4, N-NO3) independientemente del tratamiento, lo que permite inferir la no asociación de impactos adversos en el suelo por el reúso de agua residual tratada en riego de caña de azúcar

    Role of intact hydrogen-bond networks in multiproton-coupled electron transfer

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    The essential role of a well-defined hydrogen-bond network in achieving chemically reversible multiproton translocations triggered by one-electron electrochemical oxidation/reduction is investigated by using pyridylbenzimidazole-phenol models. The two molecular architectures designed for these studies differ with respect to the position of the N atom on the pyridyl ring. In one of the structures, a hydrogen-bond network extends uninterrupted across the molecule from the phenol to the pyridyl group. Experimental and theoretical evidence indicates that an overall chemically reversible two-proton-coupled electron-transfer process (E2PT) takes place upon electrochemical oxidation of the phenol. This E2PT process yields the pyridinium cation and is observed regardless of the cyclic voltammogram scan rate. In contrast, when the hydrogen-bond network is disrupted, as seen in the isomer, at high scan rates (μ1000 mV s-1) a chemically reversible process is observed with an E1/2 characteristic of a one-proton-coupled electron-transfer process (E1PT). At slow cyclic voltammetric scan rates (<1000 mV s-1) oxidation of the phenol results in an overall chemically irreversible two-proton-coupled electron-transfer process in which the second proton-transfer step yields the pyridinium cation detected by infrared spectroelectrochemistry. In this case, we postulate an initial intramolecular proton-coupled electron-transfer step yielding the E1PT product followed by a slow, likely intermolecular chemical step involving a second proton transfer to give the E2PT product. Insights into the electrochemical behavior of these systems are provided by theoretical calculations of the electrostatic potentials and electric fields at the site of the transferring protons for the forward and reverse processes. This work addresses a fundamental design principle for constructing molecular wires where protons are translocated over varied distances by a Grotthuss-type mechanism.Fil: Guerra, Walter Damián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina. Arizona State University; Estados UnidosFil: Odella, Emmanuel. Arizona State University; Estados Unidos. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Secor, Maxim. University of Yale; Estados UnidosFil: Goings, Joshua J.. University of Yale; Estados UnidosFil: Urrutia, María N.. Arizona State University; Estados UnidosFil: Wadsworth, Brian L.. Arizona State University; Estados UnidosFil: Gervaldo, Miguel Andres. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Sereno, Leonides Edmundo. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Moore, Thomas A.. Arizona State University; Estados UnidosFil: Moore, Gary F.. Arizona State University; Estados UnidosFil: Hammes-Schiffer, Sharon. University of Yale; Estados UnidosFil: Moore, Ana L.. University of Yale; Estados Unido

    HIF1 alpha Suppresses Tumor Cell Proliferation through Inhibition of Aspartate Biosynthesis

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    Cellular aspartate drives cancer cell proliferation, but signaling pathways that rewire aspartate biosynthesis to control cell growth remain largely unknown. Hypoxia-inducible factor-1α (HIF1α) can suppress tumor cell proliferation. Here, we discovered that HIF1α acts as a direct repressor of aspartate biosynthesis involving the suppression of several key aspartate-producing proteins, including cytosolic glutamic-oxaloacetic transaminase-1 (GOT1) and mitochondrial GOT2. Accordingly, HIF1α suppresses aspartate production from both glutamine oxidation as well as the glutamine reductive pathway. Strikingly, the addition of aspartate to the culture medium is sufficient to relieve HIF1α-dependent repression of tumor cell proliferation. Furthermore, these key aspartate-producing players are specifically repressed in VHL-deficient human renal carcinomas, a paradigmatic tumor type in which HIF1α acts as a tumor suppressor, highlighting the in vivo relevance of these findings. In conclusion, we show that HIF1α inhibits cytosolic and mitochondrial aspartate biosynthesis and that this mechanism is the molecular basis for HIF1α tumor suppressor activity.status: publishe

    Discovery of a z=0.65 post-starburst BAL quasar in the DES supernova fields

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    We present the discovery of a z = 0.65 low-ionization broad absorption line (LoBAL) quasar in a post-starburst galaxy in data from the Dark Energy Survey (DES) and spectroscopy from the Australian Dark Energy Survey (OzDES). LoBAL quasars are a minority of all BALs, and rarer still is that this object also exhibits broad Fe ii (an FeLoBAL) and Balmer absorption. This is the first BAL quasar that has signatures of recently truncated star formation, which we estimate ended about 40 Myr ago. The characteristic signatures of an FeLoBAL require high column densities, which could be explained by the emergence of a young quasar from an early, dust-enshrouded phase, or by clouds compressed by a blast wave. The age of the starburst component is comparable to estimates of the lifetime of quasars, so if we assume the quasar activity is related to the truncation of the star formation, this object is better explained by the blast wave scenario

    BJS commission on surgery and perioperative care post-COVID-19

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    Background: Coronavirus disease 2019 (COVID-19) was declared a pandemic by the WHO on 11 March 2020 and global surgical practice was compromised. This Commission aimed to document and reflect on the changes seen in the surgical environment during the pandemic, by reviewing colleagues experiences and published evidence. Methods: In late 2020, BJS contacted colleagues across the global surgical community and asked them to describe how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had affected their practice. In addition to this, the Commission undertook a literature review on the impact of COVID-19 on surgery and perioperative care. A thematic analysis was performed to identify the issues most frequently encountered by the correspondents, as well as the solutions and ideas suggested to address them. Results: BJS received communications for this Commission from leading clinicians and academics across a variety of surgical specialties in every inhabited continent. The responses from all over the world provided insights into multiple facets of surgical practice from a governmental level to individual clinical practice and training. Conclusion: The COVID-19 pandemic has uncovered a variety of problems in healthcare systems, including negative impacts on surgical practice. Global surgical multidisciplinary teams are working collaboratively to address research questions about the future of surgery in the post-COVID-19 era. The COVID-19 pandemic is severely damaging surgical training. The establishment of a multidisciplinary ethics committee should be encouraged at all surgical oncology centres. Innovative leadership and collaboration is vital in the post-COVID-19 era

    BJS commission on surgery and perioperative care post-COVID-19

    Get PDF
    Coronavirus disease 2019 (COVID-19) was declared a pandemic by the WHO on 11 March 2020 and global surgical practice was compromised. This Commission aimed to document and reflect on the changes seen in the surgical environment during the pandemic, by reviewing colleagues' experiences and published evidence
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