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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

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

Splenic rupture following colonoscopy

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World Journal of Gastroenterology 2008年第41期14卷 6410-6412页

作者： juan Francisco Guerra Ignacio San Francisco Fernando Pimentel luis Ibanez Departamento de Cirugía Digestiva Pontificia Universidad Católica de Chile Marcoleta 367

Colonoscopy is a safe and routinely performed diagnostic and therapeutic procedure for different colorectal diseases. Although the most common complications are bleeding and perforation, extracolonic or visceral injuries have also been described. Splenic rupture is a rare complication following colonoscopy, with few cases reported. We report a 60-year-old female who presented to surgical consultation 8 h after a diagnostic colonoscopy. Clinical, laboratory and imaging findings were suggestive for a massive hemoperitoneum. At surgery, an almost complete splenic disruption was evident, and an urgent splenectomy was performed. After an uneventful postoperative period, she was discharged home. Splenic injury following colonoscopy is considered infrequent. Direct trauma and excessive traction of the splenocolic ligament can explain the occurrence of this complication. Many times the diagnosis is delayed because the symptoms are due to colonic insuffl ation, so the most frequent treatment is an urgent splenectomy. A high index of suspicion needs an early diagnosis and adequate therapy.

关键词： Colonoscopy Splenic injury Splenic rupture Splenectomy

Comprehensive control for unified power quality conditioners

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Journal of Modern Power Systems and Clean Energy 2017年第4期5卷 609-619页

作者： Miguel OCHOA-GIMéNEZ Aurelio GARCíA-CERRADA juan luis ZAMORA-MACHO Gamesa Electric S.A. 28823 CosladaMadridSpain School of Engineering Comillas Pontifical University28015 MadridSpain

This paper presents a comprehensive control strategy for unified power quality conditioners(UPQCs) to compensate for both voltage and current quality *** controllers for the series and shunt components of the UPQC are, equally, divided into three blocks: à main controller, which deals with the fundamental-frequency issues such as active and reactive power flow;` harmonic controller, which ensures zero-error tracking while compensating voltage and current harmonics;′ the set-point generation block, which handles the different control objectives of the UPQC. The controller design procedure has been simplified to the selection of three parameters for each converter. Furthermore, the proposed strategy can be implemented measuring only four variables, which represents a reasonable number of sensors. In addition, a pulse width modulation(PWM)-based modulation with fixed switching frequency is used for both converters. The proposed control strategy has been validated experimentally under different conditions, including grid-frequency variations.

关键词： Unified power quality conditioner(UPQC) Powerquality Harmoniccontrol Pulse width modulation(PWM)

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

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

Lighting,colour and geometry:Which has the greatest influence on students’cognitive processes?

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Frontiers of Architectural Research 2023年第4期12卷 575-586页

作者： Marıa luisa Nole Fajardo juan luis Higuera-Trujillo Carmen Llinares Instituto Universitario de Investigacio´n en Tecnologı´a Centrada en el Ser Humano(HUMAN-tech) Universitat Polite`cnica de Vale`nciaValencia 46022Spain School of Architecture Art and DesignTecnologico de MonterreyMonterrey 64849Mexico

Many studies have analysed the effects that design elements,such as lighting and colour,have on students’cognitive *** analyses,while providing useful information,do not allow researchers to compare the effects of multiple design *** objective of the present study is to analyse the relative influence of lighting,colour and geometry on attention and memory,the main cognitive functions that underlie learning,and on *** a controlled,virtual reality(VR)-based experiment,200 university students(100 male/100 female)performed attention,memory and preference tests in classrooms with different configurations of lighting(colour temperature and illuminance),colour(saturation and hue)and geometry(height and width).The results identified significant gender-based differences,which demonstrates the need to segment,by gender,samples in this type of *** had the greatest influence,significantly affecting males’memories,females’attention and the preferences of both *** was also an influential element,significantly affecting females’attention,while geometry was the least ***,it should be highlighted that attention was the metric most sensitive to design *** results may be of interest to architects,interior designers and engineers who wish to create classrooms that satisfy students’psychological needs.

关键词： Classroom design Memory Attention Preference Virtual classroom

Combined cell-based therapy strategies for the treatment of Parkinson's disease:focus on mesenchymal stromal cells

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Neural Regeneration Research 2023年第3期18卷 478-484页

作者： Jannette Rodríguez-Pallares María García-Garrote juan A.Parga Joséluis Labandeira-García Laboratory of Cellular and Molecular Neurobiology of Parkinson´s Disease Research Center for Molecular Medicine and Chronic Diseases(CiMUS)IDISDepartment of Morphological SciencesUniversity of Santiago de CompostelaSantiago de CompostelaSpain Networking Research Center on Neurodegenerative Diseases(CIBERNED) MadridSpain

Parkinson’s disease is a neurodegenerative condition characterized by motor impairments caused by the selective loss of dopaminergic neurons in the substantia *** is an effective and well-tolerated dopamine replacement ***,levodopa provides only symptomatic improvements,without affecting the underlying pathology,and is associated with side effects after long-term ***-based replacement is a promising strategy that offers the possibility to replace lost neurons in Parkinson’s disease *** studies of transplantation of human fetal ventral mesencephalic tissue have provided evidence that the grafted dopaminergic neurons can reinnervate the striatum,release dopamine,integrate into the host neural circuits,and improve motor *** of the limiting factors for cell therapy in Parkinson’s disease is the low survival rate of grafted dopaminergic *** factors could cause cell death of dopaminergic neurons after grafting such as mechanical trauma,growth factor deprivation,hypoxia,and *** factors play an essential role in the survival of grafted ***,direct,timely,and controllable delivery of neurotrophic factors into the brain faces important *** types of cells secrete neurotrophic factors constitutively and co-transplantation of these cells with dopaminergic neurons represents a feasible strategy to increase neuronal *** this review,we provide a general overview of the pioneering studies on cell transplantation developed in patients and animal models of Parkinson’s disease,with a focus on neurotrophic factor-secreting cells,with a particular interest in mesenchymal stromal cells;that co-implanted with dopaminergic neurons would serve as a strategy to increase cell survival and improve graft outcomes.

关键词： brain repair cell replacement co-grafts dopaminergic neurons fetal ventral mesencephalic tissue mesenchymal stem cells neural grafting neural transplantation neuroblasts neurotrophic factors