Influence of Multiple Conformations and Paths on Rate Constants and Product Branching Ratios. Thermal Decomposition of 1-Propanol Radicals

The potential energy surface involved in the thermal decomposition of 1-propanol radicals was investigated in detail using automated codes (tsscds2018 and Q2DTor). From the predicted elementary reactions, a relevant reaction network was constructed to study the decomposition at temperatures in the range 1000–2000 K. Specifically, this relevant network comprises 18 conformational reaction channels (CRCs), which in general exhibit a large wealth of conformers of reactants and transition states. Rate constants for all the CRCs were calculated using two approaches within the formulation of variational transition-state theory (VTST), as incorporated in the TheRa program. The simplest, one-well (1W) approach considers only the most stable conformer of the reactant and that of the transition state. In the second, more accurate approach, contributions from all the reactant and transition-state conformers are taken into account using the multipath (MP) formulation of VTST. In addition, kinetic Monte Carlo (KMC) simulations were performed to compute product branching ratios. The results show significant differences between the values of the rate constants calculated with the two VTST approaches. In addition, the KMC simulations carried out with the two sets of rate constants indicate that, depending on the radical considered as reactant, the 1W and the MP approaches may display different qualitative pictures of the whole decomposition processThis work was partially supported by the Consellería de Cultura, Educación e Ordenación Universitaria e da Consellería de Economía, Emprego e Industria (Axuda para Consolidación e Estructuración de unidades de investigación competitivas do Sistema Universitario de Galicia, Xunta de Galicia ED431C 2017/17 & Centro singular de investigación de Galicia acreditación 2016-2019, ED431G/09), the Ministerio de Economía y Competitividad of Spain (Research Grant No CTQ2014-58617-R), and the European Regional Development Fund (ERDF). D.F.-C. also thanks Xunta de Galicia for financial support through a postdoctoral grant. The authors thank “Centro de Supercomputación de Galicia (CESGA)” for the use of their computational facilitiesS

Introducing Fe and Mn as catalysts for the selective functionalization of Csp2-H bonds of arenes by carbene insertion

Título de la versión post-print: Introducing Fe and Mn as catalysts for the selective functionalization of Csp2-H bonds of arenes by carbene insertionThe first examples of the direct functionalization of non-activated aryl sp(2) C-H bonds with ethyl diazoacetate (N2CHCO2Et) catalyzed by Mn- or Fe-based complexes in a completely selective manner are reported, with no formation of the frequently observed cycloheptatriene derivatives through competing Buchner reaction. The best catalysts are Fe-II or Mn-II complexes bearing the tetradentate pytacn ligand (pytacn = 1-(2-pyridylmethyl)-4,7-dimethyl-1,4,7-triazacyclononane). When using alkylbenzenes, the alkylic C(sp(3))-H bonds of the substituents remained unmodified, thus the reaction being also selective toward functionalization of sp(2) C-H bonds.Support for this work was provided by the MINECO (CTQ2014-52769-C3-R-1, CTQ2014-62234-EXP, CTQ2015-70795-P, CTQ2014-54306-P, and CTQ2014-52525P), and the Junta de Andalucia (P10-FQM-06292). A.C. thanks Junta de Andalucia for a research contract. M.C. acknowledges an ICREA Academia Award, 2014 SGR 862 from Generalitat de Catalunya, and ERC-239910

An Assessment of Beaked Redfish (S. mentella and S. fasciatus) in NAFO Division 3M (With a Revised Approach to Quantify the Increase on Redfish Natural Mortality Determined by the Increase on Cod Predation Observed Over Recent Years, 2006-2012)

The 3M redfish assessment is focused on the beaked redfish, regarded as a management unit composed of two populations from two very similar species: the Flemish Cap S. mentella and S. fasciatus. The reason for this approach is the historical dominance of this group in the 3M redfish commercial catch until 2005. However a new golden redfish fishery (S. marinus) started on September 2005 on shallower depths of the Flemish Cap bank above 300m, and the Flemish Cap cod fishery reopened in 2010. These new realities implied a revision of catch estimates, in order to split recent redfish commercial catch and by-catch from the major fleets on Div. 3M into golden (S. marinus) and beaked (S. mentella and S. fasciatus) redfish catches. An Extended Survivor Analysis (Shepherd, 1999) was used with the same framework of previous assessments and with the tuning of the 1989-2012 EU survey. Survey results suggest that the beaked redfish stock has not been able to hold its growth and sustain an above average level, suffering instead a severe decline on the second half of the 2000’s. The most likely hypothesis to justify this unexpected downward trend on stock size is an increase in natural mortality by cod predation. From the sensitive analysis, natural mortality at 0.4 was applied on ages 4-6 through 2006-2010, and extended to ages 7 plus on 2009 and 2010. It has been kept constant through all ages on 2011 and 2012, but with an overall decline to 0.125.This is the highest possible level of natural mortality giving assessment results in line with the recent survey trends and at the same time with key diagnostics very close to the best ones, obtained with the return on 2011-2012 to the “standard” redfish natural mortality of 0.1. A 2013-2009 retrospective XSA was also carried out, being this assessment very much in line with their immediate predecessors (2012-2011). Above average year classes coupled with low fishing mortalities allowed a rapid growth of biomass and abundance since 2003 that pushed the stock to a 2008-2009 high. Between 2009 and 2011 biomass and abundance of exploitable and 7 plus female stock went down for causes other than fishing. These declines were halted at well above average levels on the terminal year and, at least for biomass, there was some improvement on 2012. The recruitment at age 4 increased from 2002 till 2006 and was kept at a high level until 2009, with 2005 year class as the most abundant year class of the assessment interval. Recruitment to exploitable stock declined since then and is approaching the level of the weak year classes from the 1990’s. Short and medium term stochastic projections were obtained for female spawning stock biomass (SSB) under Fstatusquo , together with SSB and yield medium term probability profiles. As it was documented on the 2011 assessment F0.1 is an unacceptable management option at the current beaked redfish stock status. Keeping on 2014 and 2015 fishing mortality at its present low level will sustain on the short term a high level of female spawning biomass. But on the long term it will be natural mortality to determine the future of beaked redfish as a fishery resource

Identification of emerging hazards in mussels by the Galician Emerging Food Safety Risks Network (RISEGAL). A first approach

Emerging risk identification is a priority for the European Food Safety Authority (EFSA). The goal of the Galician Emerging Food Safety Risks Network (RISEGAL) is the identification of emerging risks in foods produced and commercialized in Galicia (northwest Spain) in order to propose prevention plans and mitigation strategies. In this work, RISEGAL applied a systematic approach for the identification of emerging food safety risks potentially affecting bivalve shellfish. First, a comprehensive review of scientific databases was carried out to identify hazards most quoted as emerging in bivalves in the period 2016–2018. Then, identified hazards were semiquantitatively assessed by a panel of food safety experts, who scored them accordingly with the five evaluation criteria proposed by EFSA: novelty, soundness, imminence, scale, and severity. Scores determined that perfluorinated compounds, antimicrobial resistance, Vibrio parahaemolyticus, hepatitis E virus (HEV), and antimicrobial residues are the emerging hazards that are considered most imminent and severe and that could cause safety problems of the highest scale in the bivalve value chain by the majority of the experts consulted (75%). Finally, in a preliminary way, an exploratory study carried out in the Galician Rías highlighted the presence of HEV in mussels cultivated in class B production areas.info:eu-repo/semantics/publishedVersio

The star formation history and metal content of the "Green Peas". New detailed GTC-OSIRIS spectrophotometry of three galaxies

We present deep broad-band imaging and long-slit spectroscopy of three compact, low-mass starburst galaxies at redshift z\sim0.2-0.3, also referred to as Green Peas (GP). We measure physical properties of the ionized gas and derive abundances for several species with high precision. We find that the three GPs display relatively low extinction, low oxygen abundances, and remarkably high N/O ratios We also report on the detection of clear signatures of Wolf-Rayet (WR) stars in these galaxies. We carry out a pilot spectral synthesis study using a combination of both population and evolutionary synthesis models. Their outputs are in qualitative agreement, strongly suggesting a formation history dominated by starbursts. In agreement with the presence of WR stars, these models show that these GPs currently undergo a major starburst producing between ~4% and ~20% of their stellar mass. However, as models imply, they are old galaxies having had formed most of their stellar mass several Gyr ago. The presence of old stars has been spectroscopically verified in one of the galaxies by the detection of Mg I 5167, 5173 absorption line. Additionally, we perform a surface photometry study based on HST data, that indicates that the three galaxies posses an exponential low-surface brightness envelope. If due to stellar emission, the latter is structurally compatible to the evolved hosts of luminous BCD/HII galaxies, suggesting that GPs are identifiable with major episodes in the assembly history of local BCDs. These conclusions highlight the importance of these objects as laboratories for studying galaxy evolution at late cosmic epochs.Comment: 30 pages, 9 figures and 7 tables. Accepted for publication in Ap

Arqueología en la ACEGA 2: el área arqueológica de O Peto (Vedra, A Coruña)

Cadernos de Arqueoloxía e Patrimonio (CAPA)[EN] The archaeological area of O Peto was discovered during the construction of the highway Santiago-Alto de Santo de Domingo. This site shows the existence of archaeological structures near of the galician Iron Age hillforts. In fact O Peto is an artificialized space (where a set of several structures was exhumed) that belongs to a prerroman iron mining complex that suffered several changes in the beginning of Romanization.[ES] El área arqueológica de O Peto se descubrió durante el control arqueológico de la construcción de la Autopista Santiago-Alto de Santo Domingo. Se trata de un ejemplo significativo de la existencia de estructuras anejas en el entorno inmediato del recinto habitacional de los castros de la Edad del Hierro. Constituye un espacio claramente artificializado en el que se superponen estructuras excavadas en la roca, de naturaleza y finalidad diferentes. A este respecto se configura un espacio construido –aparentemente multifuncional- que experimentó sucesivos procesos de ampliación, redefinición, sellado intencionado y abandono entre la Edad del Hierro y Época Romana. La información aportada por la excavación indica que este yacimiento albergó un complejo minerometalúrgico caracterizado tecnológicamente por la utilización de hornos bajos prerromanos sin sangrado de escoria que procesarían el mineral extraído en el propio yacimiento.Proyecto financiado por la Dirección Xeral de Investigación e Desenvolvemento da Consellería de Innovación, Industria e Comercio (Xunta de Galicia) con cargo a la convocatoria Programa de Tecnoloxías para a Innovación- Tecnoloxías da Construcción e da Conservación do Patrimonio do ano 2004. Código de Proxecto: PGIDIT04CCP606003PRPeer reviewe

Arqueología en la ACEGA 2: el área arqueológica de O Peto (Vedra, A Coruña)

Cadernos de Arqueoloxía e Patrimonio (CAPA)[EN] The archaeological area of O Peto was discovered during the construction of the highway Santiago-Alto de Santo de Domingo. This site shows the existence of archaeological structures near of the galician Iron Age hillforts. In fact O Peto is an artificialized space (where a set of several structures was exhumed) that belongs to a prerroman iron mining complex that suffered several changes in the beginning of Romanization.[ES] El área arqueológica de O Peto se descubrió durante el control arqueológico de la construcción de la Autopista Santiago-Alto de Santo Domingo. Se trata de un ejemplo significativo de la existencia de estructuras anejas en el entorno inmediato del recinto habitacional de los castros de la Edad del Hierro. Constituye un espacio claramente artificializado en el que se superponen estructuras excavadas en la roca, de naturaleza y finalidad diferentes. A este respecto se configura un espacio construido –aparentemente multifuncional- que experimentó sucesivos procesos de ampliación, redefinición, sellado intencionado y abandono entre la Edad del Hierro y Época Romana. La información aportada por la excavación indica que este yacimiento albergó un complejo minerometalúrgico caracterizado tecnológicamente por la utilización de hornos bajos prerromanos sin sangrado de escoria que procesarían el mineral extraído en el propio yacimiento.Proyecto financiado por la Dirección Xeral de Investigación e Desenvolvemento da Consellería de Innovación, Industria e Comercio (Xunta de Galicia) con cargo a la convocatoria Programa de Tecnoloxías para a Innovación- Tecnoloxías da Construcción e da Conservación do Patrimonio do ano 2004. Código de Proxecto: PGIDIT04CCP606003PRPeer reviewe

Impaired brain glymphatic flow in experimental hepatic encephalopathy

BACKGROUND AND AIMS: Neuronal function is exquisitely sensitive to alterations in extracellular environment. In patients with hepatic encephalopathy (HE), accumulation of metabolic waste products and noxious substances in the interstitial fluid of the brain is thought to be a consequence of the liver disease and may contribute to neuronal dysfunction and cognitive impairment. This study was designed to test the hypothesis that the accumulation of these substances, such as bile acids, may result from reduced clearance from the brain. METHODS: In a rat model of chronic liver disease with minimal HE (the bile duct ligation (BDL) model), we used emerging dynamic contrast-enhanced MRI and mass-spectroscopy techniques to assess the efficacy of the glymphatic system, which facilitates clearance of solutes from the brain. Immunofluorescence of aquaporin-4 (AQP4) and behavioural experiments were also performed. RESULTS: We identified discrete brain regions (olfactory bulb, prefrontal cortex and hippocampus) of altered glymphatic clearance in BDL rats, which aligned with cognitive/behavioural deficits. A significantly lower level of AQP4 expression was observed compared to the vasculature marker in both the olfactory bulb and prefrontal cortex in HE, which could be a contributing factor to the pathophysiological mechanisms underlying the impairment in glymphatic function observed in BDL rats. CONCLUSIONS: This study provides the first experimental evidence of impaired glymphatic flow in HE, potentially mediated by decreased AQP4 expression in the affected regions. LAY SUMMARY: The 'glymphatic system' is a newly discovered brain-wide pathway that facilitates clearance of various substances that accumulate in the brain due to its activity. This study evaluated whether the function of this system is altered in a model of brain dysfunction that occurs in cirrhosis. For the first time, we identified that the clearance of substances from the brain in cirrhosis is reduced because this clearance system is defective. This study proposes a new mechanism of brain dysfunction in patients with cirrhosis and provides new targets for therapy