70 research outputs found

    Context and topography determine the role of basolateral amygdala metabotropic glutamate receptor 5 in appetitive Pavlovian responding

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    Preclinical data have shown that the excitatory metabotropic Gαq-coupled glutamate receptor, mGluR5, has a role in substance abuse and relapse. However, little is known about the contribution of mGluR5 to the expression of conditioned responding elicited by appetitive Pavlovian cues. We investigated this question in rats that were trained to associate a discrete, auditory conditioned stimulus (CS) with a fructose-glucose solution (5.5% fructose/4.5% glucose; ‘sugar’). In subsequent tests for the expression of conditioned responding without sugar delivery, CS-elicited fluid port entries were elevated in a context associated with sugar, relative to an equally familiar, neutral context. Inhibiting mGluR5 via systemic injections of a negative allosteric modulator (MTEP; 5 mg/kg) reduced CS port entries in both the sugar context and neutral context. Targeting MTEP microinjections (3 µg/side; 0.3 µl/min) to the nucleus accumbens (Acb) core had no effect on CS port entries at test, whereas the same manipulation in the basolateral amygdala (BLA) produced effects that were topographically dependent. Specifically, microinjecting MTEP in the posterior BLA had no effect on behavior, whereas inhibiting mGluR5 in the anterior BLA enhanced the contextual discrimination of CS port entries. These data are the first to show a role of mGluR5 in the context-dependent expression of appetitive Pavlovian conditioned responding, with a topographically defined arrangement of mGluR5 in the BLA being particularly important for context-based responding to a discrete, appetitive cue

    Experimental and theoretical evaluations on Oleuropein as a natural origin corrosion inhibitor for copper in acidic environment

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    none5siCopper corrosion in acidic cleaning solutions is a major worry for heat exchangers. Corrosion inhibitors derived from natural sources might be a viable option. The isolation of Oleuropein compound from olive leaf and investigation of its anticorrosion potential for copper in 1.0 M H2SO4 solution are reported here. All experimental results from LC-MS, FT-IR, 1H and 13C-NMR characterizations support the molecular structure of Oleuropein. Electrochemical and gravimetric tests were used to evaluate the corrosion inhibition capabilities of Oleuropein. According to polarization investigation, Oleuropein is a mixed-type inhibitor. Oleuropein's inhibitory efficacy increases with concentration, attaining an optimum value (98.92%) at 100 mg L-1. At high temperatures, Oleuropein can be considered an efficient inhibitor. Thermodynamic variables for the activation operation and copper dissolution were computed and addressed as well. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) examinations revealed that Oleuropein produced an outer layer on the copper surface, shielding it from severe acid damage. Quantum chemical simulations were employed to propose molecular explanations for Oleuropein's inhibitory actions.Deyab, M A; Mohsen, Q; Bloise, E; Lazzoi, M R; Mele, GDeyab, M A; Mohsen, Q; Bloise, E; Lazzoi, M R; Mele,

    Dysnatremia is a predictor for morbidity and mortality in hospitalized patients with COVID-19

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    Context: Dysnatremia is an independent predictor of mortality in patients with bacterial pneumonia. There is paucity of data about the incidence and prognostic impact of abnormal sodium concentration in patients with coronavirus disease 2019 (COVID-19). Objective: This work aimed to examine the association of serum sodium during hospitalization with key clinical outcomes, including mortality, need for advanced respiratory support and acute kidney injury (AKI), and to explore the role of serum sodium as a marker of inflammatory response in COVID-19. Methods: This retrospective longitudinal cohort study, including all adult patients who presented with COVID-19 to 2 hospitals in London over an 8-week period, evaluated the association of dysnatremia (serum sodium  145 mmol/L, hyponatremia, and hypernatremia, respectively) at several time points with inpatient mortality, need for advanced ventilatory support, and AKI. Results: The study included 488 patients (median age, 68 years). At presentation, 24.6% of patients were hyponatremic, mainly due to hypovolemia, and 5.3% hypernatremic. Hypernatremia 2 days after admission and exposure to hypernatremia at any time point during hospitalization were associated with a 2.34-fold (95% CI, 1.08-5.05; P = .0014) and 3.05-fold (95% CI, 1.69-5.49; P < .0001) increased risk of death, respectively, compared to normonatremia. Hyponatremia at admission was linked with a 2.18-fold increase in the likelihood of needing ventilatory support (95% CI, 1.34-3.45, P = .0011). Hyponatremia was not a risk factor for in-hospital mortality, except for the subgroup of patients with hypovolemic hyponatremia. Sodium values were not associated with the risk for AKI and length of hospital stay. Conclusion: Abnormal sodium levels during hospitalization are risk factors for poor prognosis, with hypernatremia and hyponatremia being associated with a greater risk of death and respiratory failure, respectively. Serum sodium values could be used for risk stratification in patients with COVID-19

    Evaluación De La Influencia De Las Condiciones De Fondo De Pozo En El Deterioro De Un Acero API P110, En Ambientes Simulados Del Proceso De Combustión In Situ, Por Gravimetría Y EIS

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    RESUMEN Dada la gran cantidad de consumo del petróleo como recurso energético, tiene por consecuencia una diminución en el crudo existente a nivel mundial, la explotación del crudo pesado surge como nueva alternativa de extracción que se deja a un lado debido a las dificultades asociadas a su procesamiento. Por lo tanto el proceso de combustión in situ, es un método de extracción que facilita la producción de este tipo de crudo, pues generan un aumento en la producción a expensas de un aumento de los costos asociados a mantenimiento, pues a las condiciones operacionales se favorecen fenómenos como la corrosión de los diferentes materiales involucrados en el proceso, pues están expuestos a atmosferas de sulfuro de hierro (H2S), entre otros gases; a temperaturas y presiones elevadas, lo cual promueve la corrosión y los fenómenos de Sulfide stress cracking. Adicionalmente, los materiales se ven afectados por la acidez y la cantidad de impurezas presentes en el crudo. Por lo anterior se evaluó el comportamiento del acero API P110 expuesto a crudo pesado con diferentes contenidos de azufre (0.5 - 1.5 % en peso), TAN (2.28 - 6.84 g KOH/g crudo) a elevadas temperaturas (190 -250 °C) y presiones (8.96x106 - 11.72x106 Pa), ya que se pueden presentar estas condiciones en el proceso de extracción por combustión in situ en fondos de pozo. Se encontró que el principal mecanismo de corrosión en estas condiciones es la corrosión por sulfidación cuyos principales productos de corrosión son el FeS y óxido de hierro (Fe3O4)

    Chemical Additives for Corrosion Control in Desalination Plants

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    The addition of chemical additives has been considered as a standard operation in water treatment systems. This chapter discusses the chemical additives used for the control of corrosion in desalination systems. Specifically, corrosion inhibitors for various metallurgies, biocides, and oxygen scavengers are covered. The pros and cons of the additive chemicals have been highlighted. The need to utilize green corrosion inhibitors based on plants and ionic liquids materials have been emphasized. This class of materials are environmentally friendly, cheap, and readily available

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Background: Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. // Methods: We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung's disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. // Findings: We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung's disease) from 264 hospitals (89 in high-income countries, 166 in middle-income countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in low-income countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. // Interpretation: Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between low-income, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Exploring corrosion protection properties of alkyd@lanthanide bis-phthalocyanine nanocomposite coatings

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    Organic coatings have been widely used to protect carbon steel pipelines from external corrosion; however, they often suffer from permeability and weak adhesion
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