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Deriving the coronal hole electron temperature: electron density dependent ionization / recombination considerations

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Research in Astronomy and Astrophysics 2010年第1期10卷 91-95页

作者： John Gerard Doyle Steven Chapman paul Bryans david pérez-suárez Avninda Singh Hugh summers Daniel Wolf Savin Armagh Observatory College HillArmagh BT61 9DGN.Ireland Centre for Astrophysics University of Central LancashirePrestonUK Space Science Division Naval Research LaboratoryWashingtonDC 20375USA George Mason University 4400 University DriveFairfaxVA 22020USA Department of physics & Electronics Deen Dayal Upadhyaya CollegeUniversity of DelhiIndia Department of physics University of Strathclyde107 RottenrowGlasgowG4 0NGScotland Columbia Astrophysics Laboratory 550 W 120th StNew YorkNY 10027USA

Comparison of appropriate theoretically derived line ratios with observational data can yield estimates of a plasma＇s physical parameters, such as electron density or temperature. The usual practice in the calculation of the line ratio is the assumption of excitation by electrons/protons followed by radiative decay. Furthermore, it is normal to use the so-called coronal approximation, i.e. one only considers ionization and recombination to and from the ground-state. A more accurate treatment is to include ionization/recombination to and from metastable levels. Here, we apply this to two lines from adjacent ionization stages, Mg IX 368A and Mg × 625A, which has been shown to be a very useful temperature diagnostic. At densities typical of coronal hole conditions, the difference between the electron temperature derived assuming the zero density limit compared with the electron density dependent ionization/recombination is small. This, however, is not the case for flares where the electron density is orders of magnitude larger. The derived temperature for the coronal hole at solar maximum is around 1.04MK compared to just below 0.82MK at solar minimum.

关键词： atomic processes - line formation - sun activity

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Variation in SARS-CoV-2 seroprevalence in children in the region of Asturias,Northern Spain

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World Journal of pediatrics 2022年第12期18卷 835-844页

作者： Elisa García-García Mercedes Rodríguez-pérez david pérez-Solís Carlos pérez-Méndez Cristina Molinos-Norniella Ángeles Cobo-Ruisánchez Eva María Fernández Fernández Noelia García González Laura Calle-Miguel pediatrics Department Centro de Salud LaviadaCalle Juanín de Mieres833207GijónSpain Microbiology Department Hospital Universitario Central de AsturiasOviedoSpain pediatrics Department Hospital Universitario San AgustínAvilésSpain pediatrics Department Hospital Universitario de CabueñesGijónSpain pediatrics Department Hospital Carmen y Severo Ochoa.Cangas del NarceaSpain pediatrics Department Centro de Salud TeatinosOviedoSpain pediatrics Department Hospital Universitario Central de AsturiasOviedoSpain

Background Updated seroprevalence estimates are important to describe the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)landscape and to guide public health *** aims are to describe longitudinal changes in seroprevalence in children in a region in Northern Spain and to analyze factors associated with SARS-CoV-2 *** prospective multicenter longitudinal study with subjects recruited from July to September ***(up to 14 years old)were included and followed up until September *** blood samples were collected every six months during three testing rounds and were analyzed for SARS-CoV-2 *** data regarding epidemiological features,contact tracing,symptoms,and virological tests were *** evolution of SARS-CoV-2 seroprevalence during the study and the differences between children with positive and negative SARS-CoV-2 antibody tests were *** Two hundred children were recruited(50.5%girls,median age 9.7 years).The overall seroprevalence increased from round 1[1.5%,95%confidence interval(CI)0.3%–4.3%]to round 2(9.1%,95%CI 4.6%–12.7%)and round 3(16.6%,95%CI 9.5%–19.6%)(pp=0.001)who lived in urban areas(ppreviously positive became *** multivariable analysis,three variables independently associated with SARS-CoV-2 seropositivity were identified:close contact with coronavirus disease 2019(COVID-19)confirmed or suspected cases[odds ratio(OR)=3.9,95%CI 1.2–12.5],previous positive virological test(OR=17.1,95%CI 3.7–78.3)and fatigue(OR=18.1,95%CI 1.7–193.4).Conclusions SARS-CoV-2 seroprevalence in children has remarkably increased during the time of our *** was the only COVID-19-compatible symptom that was more frequent in seropositive than in seronegative children.

关键词： Antibodies Child COVID-19 Seroepidemiologic studies

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On the Base point Locus of surface parametrizations:Formulas and Consequences

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Communications in Mathematics and Statistics 2022年第4期10卷 757-783页

作者： david A.Cox Sonia pérez-Díaz J.Rafael Sendra Department of Mathematics and Statistics Amherst CollegeAmherstMA 01002USA Universidad de Alcalá Dpto.de Física y Matemáticas28871 MadridSpain

This paper shows that the multiplicity of the base point locus of a projective rational surface parametrization can be expressed as the degree of the content of a univariate *** a consequence,we get a new proof of the degree formula relating the degree of the surface,the degree of the parametrization,the base point multiplicity and the degree of the rational map induced by the *** addition,we extend both formulas to the case of dominant rational maps of the projective plane and describe how the base point loci of a parametrization and its reparametrizations are *** an application of these results,we explore how the degree of a surface reparametrization is affected by the presence of base points.

关键词： Base point Hilbert-Samuel multiplicity surface parametrization Reparametrization parametrization degree surface degree

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Navigating the controversy regarding antibiotic prophylaxis in acute variceal bleeding

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World Journal of Gastroenterology 2024年第18期30卷 2485-2487页

作者： david Aguirre-Villarreal Ignacio García-Juárez Department of Gastroenterology and Liver Transplant Unit Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico

Antibiotic prophylaxis in patients with cirrhosis and acute variceal bleeding is part of the standard of care according to most clinical ***,with recent evidence arguing against antibiotic prophylaxis,the role of this... 详细信息

关键词： Cirrhosis Acute variceal bleeding Antibiotic prophylaxis Endoscopic band ligation Spontaneous bacterial peritonitis

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Bone marrow-derived mononuclear stem cells in the treatment of retinal degenerations

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Neural Regeneration Research 2022年第9期17卷 1937-1944页

作者： Diego García-Ayuso Johnny Di pierdomenico david García-Bernal Manuel Vidal-Sanz María p.Villegas-pérez Departamento de Oftalmología Facultad de MedicinaUniversidad de MurciaCampus de Ciencias de la saludMurciaSpain Instituto Murciano de Investigación Biosanitaria Hospital Virgen de la Arrixaca(IMIB-Virgen de la Arrixaca) MurciaSpain Servicio de Hematología Hospital Clínico Universitario Virgen de la ArrixacaMurciaSpain

Retinal degenerative diseases affecting the outer retina in its many forms(inherited,acquired or induced)are characterized by photoreceptor loss,and represent currently a leading cause of irreversible vision loss in the *** present,there are very few treatments capable of preventing,recovering or reversing photoreceptor degeneration or the secondary retinal remodeling,which follows photoreceptor loss and can also cause the death of other retinal ***,these diseases are nowadays one of the greatest challenges in the field of ophthalmological *** marrow derived-mononuclear stem cell transplantation has shown promising results for the treatment of photoreceptor *** cells may have the potential to slow down photoreceptor loss,and therefore should be applied in the early stages of photoreceptor ***,because of their possible paracrine effects,they may have a wide range of clinical applications,since they can potentially impact on several retinal cell types at once and photoreceptor degenerations can involve different cells and/or begin in one cell type and then affect adjacent *** intraocular injection of bone marrow derived-mononuclear stem cells also enhances the outcomes of other treatments aimed to protect ***,it is likely that future investigations may combine bone marrow derived-mononuclear stem cell therapy with other systemic or intraocular treatments to obtain greater therapeutic effects in degenerative retinal diseases.

关键词： age-related macular degeneration bone marrow stem cells intravitreal injection macroglia microglia photoreceptor degeneration retinal ganglion cells retinitis pigmentosa subretinal injection transplant

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Making bridges between preclinical and clinical insights into age-related cognitive decline

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Neural Regeneration Research 2025年第8期20卷 2321-2322页

作者： david VC Brito Clévio Nóbrega Algarve Biomedical Center-Research Institute(ABC-RI) Campus GambelasFaroPortugal Algarve Biomedical Center-(ABC) Campus GambelasFaroPortugal Faculty of Medicine and Biomedical Sciences(FMCB) University of AlgarveGambelas CampusFaroPortugal

With people living longer,the societal impact of age-related cognitive decline is becoming more pronounced(Crimmins,2015).Thus,it is increasingly important to comprehend the cognitive shifts linked to aging-whether th... 详细信息

关键词： bridges becoming insight

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Women in visual neural regeneration research

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Neural Regeneration Research 2025年第2期20卷 489-490页

作者： Tonia S.Rex david J.Calkins Vanderbilt Eye Institute Vanderbilt University Medical CenterNashvilleTNUSA

The year 2024 marks the 60^(th)anniversary of Title IX and 25 years since the New York Times revealed bias against female faculty members at the Massachusetts Institute of *** take an opportunity here to examine the state of gender bias in a relatively new yet already prominent field,neural regeneration in the visual system,for which there is a well-defined context useful for this *** National Eye Institute(NEI)provided the first round of research funding for its Audacious Goals Initiative(AGI)on visual neural regeneration in 2013 and the last round in ***,we focus on this *** sources included pubMed,the National Science Foundation(NSF),the NEI,the Blue Ridge Institute for Medical Research and data from the major professional organization for eye and vision research,the Association for Research in Vision and Ophthalmology(ARVO).

关键词： neural visual Times

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Colorectal cancer screening and surveillance in patients with inflammatory bowel disease in 2021

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World Journal of Gastroenterology 2022年第5期28卷 502-516页

作者： Jose Maria Huguet Luis Ferrer-Barceló patrícia suárez Eva Sanchez Jose david prieto Victor Garcia Javier Sempere Department of Digestive Disease General University Hospital of ValenciaValencia 46014Spain

The detection of dysplasia in patients with inflammatory bowel disease(IBD)continues to be important given the increased risk of colorectal cancer in this ***,in 2017,we performed a review and update of the recommendations for the management and follow-up of patients with IBD based on the clinical practice guidelines of various scientific *** present manuscript focuses on new aspects of the detection,follow-up,and management of dysplasia according to the latest studies and *** chromoendoscopy with targeted biopsy continues to be the technique of choice for the screening and detection of dysplasia in IBD,the associated difficulties mean that it is now being compared with other techniques(virtual chromoendoscopy),which yield similar results with less technical ***,the emergence of new endoscopy techniques that are still being researched but seem promising(e.g.,confocal laser endomicroscopy and full-spectrum endoscopy),together with the development of devices that improve endoscopic visualization(e.g.,Endocuff Vision),lead us to believe that these approaches can revolutionize the screening and follow-up of dysplasia in patients with ***,further studies are warranted to define the optimal follow-up strategy in this patient population.

关键词： Colitis surveillance Colitis screening Chromoendoscopy Colorectal cancer Inflammatory bowel disease Ulcerative colitis

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Six forests in one:Tree species diversity in the Bosque protector Chongón Colonche,a lowland mountain range in coastal Ecuadorian

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Forest Ecosystems 2022年第6期9卷 725-733页

作者： Oswaldo Jadan david ADonoso Edwin ponce-Ramírez Franz pucha-Cofrep Omar Cabrera Facultad de Ciencias Agropecuarias Universidad de Cuenca12 de Octubre y Diego de TapiaCuenca010107Ecuador programa de Doctorado en Conservacion de Recursos Naturales Escuela Internacional de DoctoradoUniversidad Rey Juan CarlosMostolesMadridES-28933Spain Departamento de Biología Escuela Politecnica NacionalLadron de Guevara E11⋅253Quito170525Ecuador Geoforest S.A 12 de febrero y Av.Franklin VegaMacas140150Ecuador Grupo de Investigacion Hidrología y Climatología Universidad Tecnica Particular de LojaSan Cayetano Alto S/NLoja110101Ecuador Brandenburg University of Technology(BTU)Cottbus-Senftenberg 03044CottbusGermany Departamento de Ciencias Biologicas y Agropecuarias Universidad Tecnica Particular de LojaSan Cayetano Alto S/NLoja110101Ecuador

Tropical mountain ranges shape the structure of tree communities and promote highly diverse natural ***“Bosque protector Chong on-Colonche”(BpCC),an 86,000-ha mountain formation situated on the coast of Ecuador,is biogeographically important for the region by connecting floristic elements of the wet Choco and the dry Tumbesian *** understanding of the factors that model tree and palm diversity and distribution in this mountain range are *** measured and identified all trees and palms(DBH≥10 cm)in 289 plots of0.2 ha,distributed throughout *** used generalized linear models to explain the relationship between forest diversity and structure and climatic variables(temperature,rain,aridity),and *** then used cluster and non-metric multidimensional scale(NMDS)analyses to search for distinct forest communities within the *** partition(varpart)was used to determine which predictor variables best explained these distinct forest communities.A species indicator analysis identified the species most likely to define these distinct forest ***,we carried out a niche modeling approach to identify the potential distribution of these forest communities within *** total,we identified 220 tree and palm species in our *** average number of species per plot was 17.8±5.8,ranging from 3 to 40 *** methods sorted the 289study plots into six different forest communities,three communities in the dry forest and three in the semi-humid Garúa *** and temperature,but not altitude or aridity,explained floristic *** results emphasize the high but little cataloged diversity in the lowland mountain rainforests of coastal Ecuador.

关键词： Chongón-Colonche Climatic variables Dry forest Forest communities Garúa forest

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suppression Effects on pineapple Soil-Borne pathogens by Crotalaria juncea,Dolomitic Lime and plastic Mulch Cover on MD-2 Hybrid Cultivar

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phyton-International Journal of Experimental Botany 2021年第4期90卷 1205-1216页

作者： Luis Alfonso Aguilar pérez Daniel NietoÁngel Moisés Roberto Vallejo pérez Daniel Leobardo Ochoa Martínez david Espinosa Victoria Andrés Rebolledo Martinez Abel Rebouças São José Fitopatología Colegio de PostgraduadosMontecillo-Texcoco56230México CONACyT-Universidad Autónoma de San Luis potosí CIACYTSan Luis Potosí78000México Edafología Colegio de PostgraduadosMontecillo-Texcoco56230México Instituto Nacional de Investigaciones Forestales Agrícolas y PecuariasVeracruz94270México Rebouças São José A.UESB/DFZVitória da Conquista95Brasil

The development and implementation of sustainable and environmentally friendly agricultural practices are indispensable as alternatives to pesticide use and to keep populations of soil-borne plant pathogens at levels that do not affect crop *** present research evaluates the incidence of soil-borne phytopathogens on the pineapple variety MD-2,which was subjected to different treatments:Incorporation of Crotalaria juncea into the soil(organic amendment),application of dolomitic lime to soil(inorganic amendment),and the use of plastic mulch covering the *** the crop cycle(15 months),the following variables were evaluated:plant height(cm),fruit weight(kg·plant^(−1)),crop yield(ton·ha^(−1)),the bud root disease incidence caused by phytophthora nicotianae,number of soil phytoparasitic nematodes and colony-forming-units(CFUs)of soil fungi and *** results indicate that Crotalaria juncea treatment reduced the pathogen population(nematode and oomycetes)at levels that did not affect crop development,so that yield increased(18–20%).The incorporation of *** into the soil as an organic amendment favors the populations of fungi disease suppressors(Trichoderma-Aspergillus).The phytoparasitic nematodes(Meloidogyne sp.,pratylenchus sp.,and Mesocriconema sp.)and oomycetes(phytophthora spp.,and pythium spp.)showed a reduction of their population levels by effects of organic amendment(***).The plastic mulch was also effective,probably due to the maintenance of optimal condition to crop growth and weed ***,the dolomitic lime application had the poorest effect under the conditions of the study area on the variables *** described observations are characteristics of a system-based approach for the potential management of soil-borne pathogens of pineapple MD-2 in Veracruz,México.

关键词： suppressive soil integrated pest management phytophthora nicotiannae phytoparasitic nematodes

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