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Suspended sediment transport in the Magdalena River(Colombia,South America):Hydrologic regime,rating parameters and effective discharge variability

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International Journal of Sediment Research 2016年第01期31卷 25-35页

作者： Aldemar Higgins juan Camilo Restrepo juan Carlos Ortiz Jorge Pierini luis Otero (UNS-CIC-CCT)

The Magdalena River has the greatest length（1612 km）and drainage area（257400 km2）of any river system in Colombia,and its watershed occupies 24%of the Colombian *** river originates in the Andean Cordillera at an elevation of 3685 m and flows to its mouth in the Caribbean Sea（Bocas de Cenizas）.For this study,information on daily flow discharge（Q）,suspended sediment transport(Qsand mean suspended sediment concentration（Cs）from 1990-2010 for the Magdalena River,based on measurements at the Caiamar gauging station（the closest station to the mouth）,was provided by the Institute of Hydrology,Meteorology and Environmental Studies of Colombia（IDEAM in Spanish）.The mean annual suspended sediment load was 169±73×10～6tyr-1for the period from 1990-1999 and145±47×10～6 t yr1for the period from 2000-2010,amounting to a 14%reduction in the suspended sediment transport rate between the two *** sediment rating curve（Qs=aQb）was also evaluated for these two periods（1990-1999 and 2000-2010）.An analysis of the regression coefficients（a.b）for the two periods showed a decrease in b and an increase in a after 1999,which coincides with a decrease in suspended sediment *** change might be attributed to natural factors,including the accumulation of sediment in the Depresion Momposina and variation in hydro-climatological patterns in the Caribbean *** in effective transport were confirmed using three methods（Log-Normal and Normal distribution,and magnitude-frequency histogram）for the study period.

关键词： Suspended sediment transport Magdalena River Transport regime Effective discharge Sediment rating curve

Characteristics and in-hospital mortality of elderly patients with heart failure in Spanish hospitals

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Journal of Geriatric Cardiology 2023年第4期20卷 247-255页

作者： Alberto Esteban-Fernández Manuel Anguita-Sánchez juan luis Bonilla-Palomas María Anguita-Gámez María garcía Joséluis Bernal Náyade Del Prado Cristina Fernández-Pérez Julián Pérez-Villacastin juan JoséGómez-Doblas Francisco Javier Elola Cardiology Department Hospital Universitario Severo OchoaMadridSpain Cardiology Department Hospital Universitario Reina SofíaCórdobaSpain Cardiology Department Hospital San Juan de la CruzÚbedaSpain Cardiology Department Hospital Clínico San CarlosMadridSpain Fundación Instituto para la Mejora de la Asistencia Sanitaria MadridSpain Management Control Department Hospital Universitario 12 de OctubreMadridSpain Department of Preventive Medicine Área Sanitaria de Santiago de Compostela y BarbanzaInstituto de Investigación de SantiagoSantiago de CompostelaSpain Cardiology Department Hospital Universitario Virgen de la VictoriaMálagaSpain

BACKGROUND The prevalence of heart failure(HF)increases with age,and it is one of the leading causes of hospitalization and death in older ***,there are little data on in-hospital mortality in patients with HF≥75 years in *** A retrospective analysis of the Spanish Minimum Basic Data Set was performed,including all HF episodes discharged from public hospitals in Spain between 2016 and *** was performed using the International Classification of Diseases,10th ***≥75 years with HF as the principal diagnosis were *** calculated:(1)the crude in-hospital mortality rate and its distribution according to age and sex;(2)the risk-standardized in-hospital mortality ratio;and(3)the association between in-hospital mortality and the availability of an intensive cardiac care unit(ICCU)in the *** We included 354,792 HF episodes of patients over 75 *** mean age was 85.2±5.5 years,and 59.2%of patients were *** most frequent comorbidities were renal failure(46.1%),diabetes mellitus(35.5%),valvular disease(33.9%),cardiorespiratory failure(29.8%),and hypertension(26.9%).In-hospital mortality was 12.7%,and increased with age[odds ratio(OR)=1.07,95%CI:1.07–1.07,P<0.001]and was lower in women(OR=0.96,95%CI:0.92–0.97,P<0.001).The main predictors of mortality were the presence of cardiogenic shock(OR=19.5,95%CI:16.8–22.7,P<0.001),stroke(OR=3.5,95%CI:3.0–4.0,P<0.001)and advanced cancer(OR=2.6,95%CI:2.5–2.8,P<0.001).In hospitals with ICCU,the in-hospital risk-adjusted mortality tended to be lower(OR=0.85,95%CI:0.72–1.00,P=0.053).CONCLUSIONS In-hospital mortality in patients with HF≥75 years between 2016 and 2019 was 12.7%,higher in males and elderly *** main predictors of mortality were cardiogenic shock,stroke,and advanced *** was a trend toward lower mortality in centers with an ICCU.

关键词： patients mortality diagnosis

Reactive oxygen species, nitric oxide and plant cell death associated with caspase-like protease activity during somatic embryogenesis in Fraxinus mandshurica

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Journal of Forestry Research 2022年第3期33卷 1005-1017页

作者： Hao Wang Dongyan Zhang juan luis Fernández-Lorenzo Hailong Shen Ling Yang State Key Laboratory of Tree Genetics and Breeding School of ForestryNortheast Forestry UniversityHarbin150040People’s Republic of China Crop Production Department High Polytechnique School of EngineeringSantiago de Compostela UniversityLugoSpain

Programmed cell death occurs in browning explants of Fraxinus mandshurica during somatic embryogenesis, but the underlying mechanism is unclear. In this study, single cotyledons of zygotic embryos of F. mandshurica were used as explants. Mitochondrial structure and function, caspase-3-like protease activity, hydrogen peroxide metabolism, and nitric oxide accumulation induced by high concentrations of sucrose and plant growth regulators were studied. The results show that plant growth regulators induced somatic embryogenesis and also promoted explant browning. High sucrose concentrations had similar effects. High concentrations of sucrose and plant growth regulators led to the accumulation of hydrogen peroxide and nitric oxide which induced changes in mitochondrial structure and function such as modifications in mitochondrial morphology, increased membrane permeability, decreased membrane potential, and the release of cytochrome c into the cytoplasm. An increase in caspase-3-like protease activity triggered programmed cell death in some browning explant cells. During somatic embryogenesis there were increased activities of superoxide dismutase, peroxidase, and catalase, which are associated with hydrogen peroxide metabolism and jointly maintain reactive oxygen species levels. Intracellular nitric oxide synthase and nitrate reductase activities were not significantly correlated with nitric oxide content. Instead, intracellular nitric oxide may be derived from non-enzymatic reactions. Our results indicate that hydrogen peroxide and nitric oxide may function as signals, playing key roles in somatic embryogenesis and programmed cell death of explant cells of F. mandshurica. The interaction between nitric oxide and reactive oxygen species determines the occurrence of programmed cell death in explant cells;somatic embryogenesis and programmed cell death are positively regulated by hydrogen peroxide. However, the regulation of nitric oxide is complex.

关键词： Manchurian ash Somatic embryogenesis Programmed cell death Mitochondria Reactive oxide species Nitric oxide

Anti-inflammatory effects of Mangifera indica *** in a model of colitis

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World Journal of Gastroenterology 2010年第39期16卷 4922-4931页

作者： Lucía Márquez Beatriz G Pérez-Nievas Icíar Gárate Borja garcía-Bueno José LM Madrigal luis Menchén Gabino Garrido juan C Leza Department of Pharmacology School of MedicineUniversity Complutense and Centro de Investigación en Red de Salud Mental(CIBERSAM) Pharmaceutical Chemistry Center and University of La Habana Health Research Institute Hospital 12 de Octubre(I+12) Gastroenterology Service Hospital General Universitario Gregorio Maraón and CIBEREHD Department of Chemistry and Pharmacy University Católica del Norte

AIM:To investigate the effect of aqueous extract from Mangifera indica L.(MIE)on dextran sulfate sodium (DSS)-induced colitis in ***:MIE(150 mg/kg)was administered in two different protocols:(1)rectally,over 7 d at the same time as DSS administration;and(2)once daily over 14 d (by oral gavage,7 d before starting DSS,and rectally for 7 d during DSS administration).General observations of clinical signs were ***-inflammatory activity of MIE was assessed by myeloperoxidase(MPO)activity. Colonic lipid peroxidation was determined by measuring the levels of thiobarbituric acid reactive substances (TBARS).Reduced glutathione(GSH)levels,expression of inflammatory related mediators[inducible isoforms of nitric oxide synthase(iNOS)and cyclooxygenase (COX)-2,respectively]and cytokines[tumor necrosis factor(TNF)-αand TNF receptors 1 and 2]in colonic tissue were also ***(IL)-6 and TNF-α serum levels were also measured. RESULTS:The results demonstrated that MIE has anti-inflammatory properties by improvement of clinical signs,reduction of ulceration and reduced MPO activity when administered before *** addition,administration of MIE for 14 d resulted in an increase in GSH and reduction of TBARS levels and iNOS,COX-2, TNF-αand TNF R-2 expression in colonic tissue,and a decrease in IL-6 and TNF-αserum levels. CONCLUSION:MIE has anti-inflammatory activity in a DSS-induced rat colitis model and preventive administration(prior to DSS)seems to be a more effective protocol.

关键词： Oxidative stress Ulcerative colitis Inflammation Polyphenols Mangifera indica Antioxidants

The Role of the Solar Cycle in the Relationship Between the North Atlantic Oscillation and Northern Hemisphere Surface Temperatures

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Advances in Atmospheric Sciences 2007年第2期24卷 191-198页

作者： Laura DE LA TORRE luis GIMENO juan Antonio AEL Raquel NIETO Universidad de Vigo Facultad de Ciencias de Ourense 32004OurenseSpain

The North Atlantic Oscillation （NAO） is one of the leading modes of climate variability in the Northern Hemisphere. It has been shown that it clearly relates to changes in meteorological variables, such as surface temperature, at hemispherical scales. However, recent studies have revealed that the NAO spatial pattern also depends upon solar forcing. Therefore, its effects on meteorological variables must vary depending upon this factor. Moreover, it could be that the Sun affects climate through variability patterns, a hypothesis that is the focus of this study. We find that the relationship between the NAO/AO and hemispheric temperature varies depending upon solar activity. The results show a positive significant correlation only when solar activity is high. Also, the results support the idea that solar activity influences tropospheric climate fluctuations in the Northern Hemisphere via the fluctuations of the stratospheric polar vortex .

关键词： solar activity North Atlantic Oscillation Arctic Oscillation Northern Hemisphere surface temperature

Implications of denitrification in the ecological status of an urban river using enzymatic activities in sediments as an indicator

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Journal of Environmental Sciences 2019年第1期31卷 255-268页

作者： Jessica Unda-Calvo Miren Martínez-Santos Estilita Ruiz-Romera juan luis Lechuga-Crespo Department of Chemical and Environmental Engineering University of the Basque Country

A better understanding of the effects of a number of environmental factors on denitrification is vital for analyzing its role as nitrogen sink and providing deeper knowledge about the ecological status of a nitrate-rich ecosystem. Since few studies have addressed the occurrence and implications of denitrification in river sediments, and complexity of interactions among all these environmental factors makes comprehension of the process difficult, the potential of sediments from the Deba River to attenuate nitrate excess through denitrification was investigated. For this purpose, we adapted an in vitro method to measure activities of two enzymes contributing to the entire multiple-step nitrate reduction: Nitrate Reductase and Nitrite Reductase. The environmental features that influence both or single enzymatic activities were identified as oxygen availability,regulated directly by the moisture content or indirectly through the aerobic respiration,organic matter and nitrate content of sediments, and electrical conductivity and exchangeable sodium percentage of water. Additionally, our results showed that Nitrate Reductase catalyzes the principal limiting step of denitrification in sediments. Therefore,taking this enzymatic activity as an indicator, the southern part of the Deba River catchment presented low potential to denitrify but nitrate-limited sediments, whereas the middle and northern parts were characterized by high denitrification potential but nitraterich sediments. In general, this study on denitrifying enzymatic activities in sediments evaluates the suitability of the management of the effluents from wastewater treatment plants and municipal sewages to ensure a good ecological status of the Deba River.

关键词： Urban catchment Sediments Denitrification Enzymatic activity Ecological status

Refractory hepatic encephalopathy in a patient with hypothyroidism: Another element in ammonia metabolism

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World Journal of Gastroenterology 2017年第28期23卷 5246-5252页

作者： Fernando Díaz-Fontenla Marta Castillo-Pradillo Arantxa Díaz-Gómez luis Ibanez-Samaniego Pilar Gancedo juan Adan Guzmán-de-Villoria Pilar Fernández-garcía Rafael Banares-Canizares Rita garcía-Martínez Unidad de Hepatología Servicio de Aparato DigestivoHospital General Universitario Gregorio Maranón Instituto de Investigación Sanitaria Hospital Gregorio Maranón Servicio de Aparato Digestivo Hospital Santa Bárbara Servicio de Radiodiagnóstico Hospital General Universitario Gregorio Maranón Centro de Investigación Biomédica en Red de Salud Mental Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas Facultad de Medicina Universidad San Pablo CEU

Hepatic encephalopathy(HE) remains a diagnosis of exclusion due to the lack of specific signs and symptoms. Refractory HE is an uncommon but serious condition that requires the search of hidden precipitating events(i.e.,portosystemic shunt) and alternative diagnosis. Hypothyroidism shares clinical manifestations with HE and is usually considered within the differential diagnosis of HE. Here,we describe a patient with refractory HE who presented a large portosystemic shunt and post-ablative hypothyroidism. Her cognitive impairment,hyperammonaemia,electroencephalograph alterations,impaired neuropsychological performance,and magnetic resonance imaging and spectroscopy disturbances were highly suggestive of HE,paralleled the course of hypothyroidism and normalized after thyroid hormone replacement. There was no need for intervention over the portosystemic shunt. The case findings support that hypothyroidism may precipitate HE in cirrhotic patients by inducing hyperammonaemia and/or enhancing ammonia brain toxicity. This case led us to consider hypothyroidism not only in the differential diagnosis but also as a precipitating factor of HE.

关键词： Hepatic encephalopathy Hypothyroidism Cognitive impairment Cirrhosis Portosystemic shunt Magnetic resonance spectroscopy

COVID-19 and Indirect Liver Injury:A Narrative Synthesis of the Evidence

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Journal of Clinical and Translational Hepatology 2021年第5期9卷 760-768页

作者： Francisco Idalsoaga Gustavo Ayares juan Pablo Arab luis Antonio Díaz Departamento de Gastroenterología Escuela de MedicinaPontificia Universidad Católica de ChileSantiagoChile Centro de Envejecimiento y Regeneración(CARE) Facultad de Ciencias BiológicasPontificia Universidad Católica de ChileSantiagoChile

The liver is frequently affected by severe acute respiratory syndrome-coronavirus 2(SARS-CoV-2)*** most common manifestations are mildly elevated alanine aminotransferase and aspartate aminotransferase,with a prevalence of 16-53%among *** with severe coronavirus disease 2019(COVID-19)seem to have higher rates of acute liver dysfunction,and the presence of abnormal liver tests at admission signifies a higher risk of severe disease during *** with chronic liver diseases also have a higher risk of severe disease and mortality(mainly seen in patients with metabolic-associated fatty liver disease).Several pathways of damage have been proposed in the liver involvement of COVID-19 patients;although,the end-cause is most likely *** liver tests have been attributed to the expression of angiotensin-converting enzyme 2 receptors in SARS-CoV-2 *** enzyme is expressed widely in cholangiocytes and less in *** factors attributed to liver damage include drug-induced liver injury,uncontrolled release of proinflammatory molecules(“cytokine storm”),pneumonia-associated hypoxia,and direct damage by the *** steatosis,vascular thrombosis,fibrosis,and inflammatory features(including Kupffer cell hyperplasia)are the most common liver histopathological findings in deceased COVID-19 patients,suggesting important indirect mechanisms of liver *** this translational medicinebased narrative review,we summarize the current data on the possible indirect mechanisms involved in liver damage due to COVID-19,the histopathological findings,and the impact of these mechanisms in patients with chronic liver disease.

关键词： COVID-19 SARS-CoV-2 Liver hepatitis Liver injury Novel coronavirus

Electrochemical and spectroscopic study of interfacial interactions between chalcopyrite and typical flotation process reagents

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 127-136页

作者： Gustavo Urbano Isabel Lázaro Israel Rodríguez juan luis Reyes Roxana Larios Roel Cruz Instituto de Metalurgia Universidad Autonotrla de San Luis PotosiAvSierra Leona 550Lomas 2a SeccionSan Luis PotosiS.L.P.78210Mexico Industrial Minera Mexico S.A.de C.V. San Luis PotosiS.L.P.Mexico Centro Universitario de Ciencias Exactas e Ingenierias Universidad de GuadalajaraGuadalajaraJaliscoMexico

Comparative voltammetry and differential double-layer capacitance studies were performed to evaluate interfacial interactions between cnalcopyrite（CuFeS2） and n-isopropyl xanthate（X） in the presence of ammonium bisulfite/39wt%SO2 and caustic starch at different pH *** spectroscopy,Fourier transform infrared（FTIR） spectroscopy,contact angle measurements,and microflotation tests were used to establish the type and extent of xanthate adsorption as well as the species involved under different mineral surface conditions in this *** results demonstrate that the species that favor a greater hydrophobicity of chalcopyrite are primarily CuX and S^0,whereas oxides and hydroxides of Cu and Fe as well as an excess of starch decrease the hydrophobicity.A conditioning of the mineral surface with ammonium bisulfite/39wt%SO2 at pH 6 promotes the activation of surface and enhances the xanthate ***,this effect is diminished at pH ≥ 8,when an excess of starch is added during the preconditioning step.

关键词： sulfide minerals chalcopyrite xanthates flotation interfacial reactions electrochemistry spectroscopy