检索结果-南通市图书馆

Use of geochemical fingerprints to trace sediment sources in an agricultural catchment of Argentina

International Soil and Water Conservation Research 2020年第4期8卷 410-417页

作者： romina Torres Astorga Yanina Garcias Gisela Borgatello Hugo Velasco román Padilla Gerd Dercon Lionel Mabit IMASL UNSLCONICET.Ejde los Andes 950San LuisArgentina nuclear Science and Instrumentation Laboratory Division of Physical and Chemical SciencesIAEASeibersdorfAustria Soil and Water Management&Crop nutrition Laboratory Joint FAO/IAEA Division of Nuclear Techniques in Food and AgricultureSeibersdorfAustria

Soil erosion and associated sediment redistribution are key environmental problems in Central *** land uses and management practices,such as intensive grazing and crop cultivation,are considered to be significantly driving and accelerating these *** research focuses on the identification of suitable soil tracers from hot spots of land degradation and sediment fate in an agricultural catchment of central Argentina with erodible loess *** Energy Dispersive X-Ray Fluorescence(EDXRF),elemental concentrations were determined and later used as soil tracers for geochemical *** best set of tracers were identified using two artificial mixtures composed of known proportions of soil sources collected from different lands having contrasting soil ***,calcium,iron,phosphorus,and titanium were identified for obtaining the best suitable reconstruction of source proportions in the laboratory-prepared artificial ***,these elements,as well as the total organic carbon,were applied for pinpointing critical hot spots of erosion within the studied *** were identified to be the main source of sediments,river banks and dirt roads together are the second most important *** investigation provides key information for optimizing soil conservation strategies and selecting land management practices and land uses which do not generate great contribution of sediment,preventing pollution of the waterways of the region.

关键词： Fingerprinting Geochemical elements Energy dispersive X-ray fluorescence Soil erosion Mixing models

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Unraveling one billion years of geological evolution of the southeastern Amazonia Craton from detrital zircon analyses

引用

Geoscience Frontiers 2022年第5期13卷 129-152页

作者： Camille Rossignol Paul Yves Jean Antonio Francesco narduzzi Eric Siciliano Rego Lívia Teixeira romário Almeida de Souza Janaína n.Ávila Marco A.L.Silva Cristiano Lana ricardo I.F.Trindade Pascal Philippot Departamento de Geofísica Instituto de AstronomiaGeofísica e Ciências Atmosféricas da Universidade de São PauloRua do Matão1226-Cidade UniversitáriaSão Paulo 05508-090Brazil Institut de Physique du Globe de Paris Universitéde ParisCNRSParisFrance Géosciences Montpellier Universitéde MontpellierCNRSUniversitédes AntillesMontpellierFrance Instituto de Geociências Universidade de São PauloRua do Lago562-Cidade UniversitáriaSão Paulo 05508-080Brazil Instituto de Geociências e Engenharias Universidade Federal do Sul e Sudeste do Pará–UNIFESSPAFolha 17Quadra 04Lote especialNova MarabáMarabáPará68505-080Brazil Research School of Earth Sciences The Australian National University142 Mills RoadCanberraACT 2601Australia Applied Isotope Research Group Departamento de GeologiaEscola de MinasUniversidade Federal de Ouro PretoRua Diogo de Vasconcelos12235400-000 Ouro PretoMGBrazil

Despite representing one of the largest cratons on Earth,the early geological evolution of the Amazonia Craton remains poorly known due to relatively poor exposure and because younger metamorphic and tectonic events have obscured initial *** this study,we investigated the sedimentary archives of the Carajás Basin to unravel the early geological evolution of the southeastern Amazonia *** Carajás Basin contains sedimentary rocks that were deposited throughout a long period spanning more than one billion years from the Mesoarchean to the *** oldest archives preserved in this basin consist of a few ca.3.6 Ga detrital zircon grains showing that the geological roots of the Amazonia Craton were already formed by the *** the Paleoarchean or the early Mesoarchean(n was large and rigid enough to sustain the formation and preservation of the Rio novo Group greenstone ***,during the neoarchean,at ca.2.7 Ga,the southeastern Amazonia Craton witnessed the emplacement of the Parauapebas Large Igneous Province(LIP)that probably covered a large part of the craton and was associated with the deposition of some of the world largest iron *** emplacement of this LIP immediately preceded a period of continental extension that formed a rift infilled first by iron formations followed by terrigenous *** major change of sedimentary regime might have been controlled by the regional tectonic evolution of the Amazonia Craton and its emergence above *** the Paleoproterozoic,at ca.2.1 Ga,the Rio Fresco Group,consisting of terrigenous sediments from the interior of the Amazonia Craton,was deposited in the Carajás *** that time,the Amazonian lithosphere could have either underwent thermal subsidence forming a large intracratonic basin or could have been deformed by long wavelength flexures that induced the formation of basins and swells throughout the craton under the influence of

关键词： Carajás Basin Chemical Abrasion–LA-ICP-MS analyses Age distribution comparison Parauapebas Large Igneous Province Transamazonian orogeny

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Identification of tree groups used by secondary cavity-nesting birds to simplify forest management in subtropical forests

引用

Journal of Forestry Research 2020年第4期31卷 1417-1424页

作者： Alejandro A.Schaaf román A.Ruggera Ever Tallei Constanza G.Vivanco Luis Rivera natalia Politi Instituto de Ecorregiones Andinas(InECOA) Universidad Nacional de Jujuy–Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Av.Bolivia 12394600 San Salvador de JujuyJujuyArgentina Fundación CEBio Roca 444600 San Salvador de JujuyJujuyArgentina

In tropical and subtropical forest ecosystems,cavities formed by decay processes are a key but scarce resource for birds that nest and roost in them,which makes them a highly sensitive group to *** piedmont forest of northwestern Argentina is a complex ecosystem with 113 tree and 120 bird *** has high logging pressure on the few,well-conserved forest remnants,complicating the delineation of sustainable management guidelines for each tree or bird species in a short *** objective was to reduce the complexity of subtropical forests by grouping tree species according to the characteristics used by secondary cavity-nesting birds(*** excavators).In the piedmont forest,50 plots of 0.25 ha were sampled to record cavity trees and cavity *** were then used in a cluster analysis to form tree ***,cavities were searched to identify the bird species using the decay-formed cavities.A total of 187 cavity trees,comprising 23 tree species,were recorded,and these formed four tree groups or *** recorded 86 cavities that were used by secondary cavitynesting bird *** four tree groups were unequally used by secondary cavity *** tree group that included valuable timber species(Myroxylon peruiferum,Anadenanthera colubrina and Calycophyllum multiflorum)and had the greatest cavity availability represented 71%of total cavity *** tree group with valuable timber species(Cedrela balansae and Amburana cearensis),measured>73 cm DBH and>21 m tall,had cavity entrances>0.10 cm2,and contributed 14%of all cavity use by birds.A third group had no highly economically valuable tree species,and included the snag category(*** dead trees)as well as a 15%of cavity *** fourth tree group had a DBHnly one highly economically valuable tree species(Cordia trichotoma),and supported no cavity *** clustering of subtropical trees can reduce the complexity of these forests,hence easing their management by

关键词： Biodiversity Cavity-nesting birds Conservation Logging

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Clinical perspectives,assessment,and mechanisms of metabolicassociated fatty liver disease in patients with COVID-19

引用

World Journal of Gastroenterology 2021年第33期27卷 5502-5519页

作者： Alejandro Campos-Murguía Berenice M román-Calleja JoséA González-Regueiro Ivonne Hurtado-Díaz-de-León Alberto Adrián Solís-Ortega nayelli C Flores-García Ignacio García-Juárez Astrid Ruiz-Margáin ricardo Ulises Macías-Rodríguez Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico Liver Fibrosis and nutrition Lab(LFnLab) MICTLÁN-Network(Mechanisms of Liver InjuryCell Death and Translational Nutrition in Liver Diseases-Research Network)Mexico City 14080Mexico

Metabolic diseases are highly prevalent worldwide and have been associated with adverse clinical outcomes,including mortality,in patients developing coronavirus disease(COVID-19).Because of the close relationship between metabolic diseases such as type 2 diabetes mellitus and obesity and the presence of metabolicassociated fatty liver disease(MAFLD),a high number of cases of patients affected by both MAFLD and COVID-19 would be expected,especially in highrisk *** studies have shown an increased risk of adverse clinical outcomes,viral shedding,and deep vein thrombosis,especially in patients with MAFLD-related liver *** predisposition to poor outcomes and severe acute respiratory syndrome coronavirus 2 infection in patients with MAFLD could be secondary to mechanisms common to both,including preexisting systemic chronic inflammation,endothelial dysfunction,and involvement of the renin-angiotensin *** of the increased risk of adverse outcomes,MAFLD should be screened in all patients admitted for *** computed tomography scans could be of help,assessment of liver fibrosis is also recommended,favoring noninvasive methods to limit the exposure of healthcare *** involvement in this population ranges from abnormalities in liver chemistry to hepatic steatosis in postmortem ***,preventive measures should be strongly advocated in patients already known to have MAFLD,including the use of telemedicine and vaccination in addition to general measures.

关键词： Metabolic-associated fatty liver disease COVID-19 Mortality Fibrosis Histology Epidemiology

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Southward Migration of Magmatic Activity in the Colima Volcanic Complex, Mexico: An Ongoing Process

引用

International Journal of Geosciences 2015年第9期6卷 1077-1099页

作者： román Alvarez Vsevolod Yutsis Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas Universidad Nacional Autónoma de México Ciudad Universitaria México DF México Instituto Potosino de Investigación Científica y Tecnológica San Luis Potosí México

The Colima Volcanic Complex trends in a nearly n-S direction in western Mexico, and one of its?structures, Colima volcano, is the most historically active volcano in the country. Immediately to the?n, there is another volcanic center called El Cántaro volcano, whose activity started around 1.7 Ma in its n portion and migrated to the S in various episodes. Volcanic activity migrated further south, from El Cántaro to the Colima Volcanic Complex where the southernmost manifestation, Hijos del Volcán domes, is located on the south slope of Fuego volcano. The above date appears to mark initiation of the rather continuous volcanic activity in the area. It has been noted that these volcanic manifestations lie on, or near the Rivera-Cocos inland plate boundary. Colima’s Fuego volcano is also the closest to the Middle America Trench, among the polygenetic volcanoes in Mexico. We submit that the anomalous location of volcanism in this area originates in an anomalous subduction process of the Rivera and Cocos plates and evoke a tectonic model, proposed elsewhere, to support the idea. Modeling gravimetric and aeromagnetic data we locate the magma chambers of the Fuego (active) and nevado (extinct) volcanoes within a 65 mGals negative Bouguer anomaly elongated in a nearly n-S direction. The corresponding aeromagnetic map displays a magnetic high over the southern portion of the Fuego volcano edifice. We found two additional, associated structures whose anomalies have not been previously reported, which appear to follow the southward magmatic migration pattern. One of them is a collapse structure with a circular topographic expression, and the southernmost is a low-density intrusion ~1 km below sea level, associated with a moderate topographic bulge at the surface that we interpret as a magma body. Five lines cross the anomalies;gravimetric and magnetic fields are concurrently modeled along them to locate the magmatic bodies. In addition to the 2-D models we perform 3-D gravimetr

关键词： Colima Volcanic Complex Magma Chambers Colima Volcanoes Gravimetric Modeling Magnetic Modeling

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Evolution of the Socio-cognitive Structure of Knowledge Management(1986–2015): An Author Co-citation Analysis

引用

Journal of Data and Information Science 2019年第2期4卷 36-55页

作者： Carlos Luis González-Valiente Magda León santos ricardo Arencibia-Jorge Biblioteca nacional de Cuba "José Martí" ave.Independencia Facultad de Comunicación Universidad de la Habana San Pedro entre Ermita y Avenida Independencia Empresa de Tecnologías de la Información

Purpose: The evolution of the socio-cognitive structure of the field of knowledge management(KM) during the period 1986–2015 is described. Design/methodology/approach: Records retrieved from Web of Science were submitted to author co-citation analysis(ACA) following a longitudinal perspective as of the following time slices: 1986–1996, 1997–2006, and 2007–2015. The top 10% of most cited first authors by sub-periods were mapped in bibliometric networks in order to interpret the communities formed and their ***: KM is a homogeneous field as indicated by networks results. nine classical authors are identified since they are highly co-cited in each sub-period, highlighting Ikujiro nonaka as the most influential authors in the field. The most significant communities in KM are devoted to strategic management, KM foundations, organisational learning and behaviour, and organisational theories. Major trends in the evolution of the intellectual structure of KM evidence a technological influence in 1986–1996, a strategic influence in 1997–2006, and finally a sociological influence in 2007–*** limitations: Describing a field from a single database can offer biases in terms of output coverage. Likewise, the conference proceedings and books were not used and the analysis was only based on first authors. However, the results obtained can be very useful to understand the evolution of KM *** implications: These results might be useful for managers and academicians to understand the evolution of KM field and to(re)define research activities and organisational ***/value: The novelty of this paper lies in considering ACA as a bibliometric technique to study KM research. In addition, our investigation has a wider time coverage than earlier articles.

关键词： Knowledge management Bibliometrics Author co-citation analysis Knowledge domain visualization Social network analysis Intellectual structure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Biomarkers and Echocardiography in the Postoperative Course of Pulmonary Resection Surgery

引用

Open Journal of Thoracic Surgery 2011年第1期1卷 1-8页

作者： David Andaluz-Ojeda Francisco Gandía Jose Luis Duque Itziar Gómez Begona De Gregorio Jose Alberto san román Eduardo Villacorta Department of Intensive Care Medicine Hospital Clínico Universitario Deparment of Thoracic Surgery Hospital Clínico Universitario

Background: The existence of different degrees of inflammatory reaction and right ventricular dysfunction after pulmonary resection is well known, though its detection and clinical relevance have not been sufficiently evaluated. The introduction of new biomarkers, particularly brain natriuretic peptide (BnP) and its prohormone (proBnP), together with dynamic imaging techniques such as echocardiography, could prove useful in assessing such response. The aim of this study is to describe the kinetic curve of these biomarkers during uncomplicated pulmonary resection surgery. Furthemore we have studied the right ventricular function by echocardiography in these patients Methods: Demographic data, antecedents and certain perioperative parameters, as well as plasma proBnP, troponin T and C-reactive protein (CRP) levels, were recorded in 38 patients who underwent pneumonectomy (n= 13 ) and lobectomy (n=25), before and 24, 48 and 72 hours after the operation. A transthoracic echocardiogram was carried out preoperatively and 72 hours after surgery. Results: ProBnP showed a significant increase 24 hours after surgery, with a maximum peak after 72 hours (pncreased after 24 hours, with an inflammatory peak after 48 hours (pnitude of the increase in proBnP and CRP was independent of the extent of resection (pneumonectomy versus lobectomy). Echocardiography showed a slight yet statistically significant decrease in right ventricular function (determined by tricuspid annular plane systolic excursion, TAPSE) in the pneumonectomy subgroup (p=0.01). Conclusion: The plasma proBnP elevation curve allows simple evaluation of the degree and time course of right ventricular dysfunction in the immediate postoperative period of uncomplicated pulmonary resection surgery. In stable patients, magnitude of proBnP elevation has no clinical repercussions, while slight echocardiographic changes are detectable only in pneumonectomized patients. Further studies a

关键词： Pneumonectomy Lobectomy Echocardiography Right Ventricle natriuretic Peptides C reactive Protein T Troponine Biomarkers

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Human Interaction Dynamics for Its Use in Mobile Robotics:Impedance Control for Leader-follower Formation

引用

IEEE/CAA Journal of Automatica Sinica 2017年第4期4卷 696-703页

作者： Daniel Herrera Flavio Roberti Marcos Toibero ricardo Carelli Instituto de Automatica Universidad nacional de san Juan-COnICET IEEE

A complete characterization of the behavior in human-robot interactions(HRI) includes both: the behavioral dynamics and the control laws that characterize how the behavior is regulated with the perception data. In this way, this work proposes a leader-follower coordinate control based on an impedance control that allows to establish a dynamic relation between social forces and motion error. For this, a scheme is presented to identify the impedance based on fictitious social forces, which are described by distance-based potential *** part of the validation procedure, we present an experimental comparison to select the better of two different fictitious force structures. The criteria are determined by two qualities: least impedance errors during the validation procedure and least parameter variance during the recursive estimation ***, with the best fictitious force and its identified impedance,an impedance control is designed for a mobile robot Pioneer 3AT,which is programmed to follow a human in a structured *** to results, and under the hypothesis that moving like humans will be acceptable by humans, it is believed that the proposed control improves the social acceptance of the robot for this kind of interaction.

关键词： Human modeling human-machine interaction impedance control robot dynamics social robotics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Prognostic performance of an index based on lactic dehydrogenase and transaminases for patients with liver steatosis and COVID-19

引用

World Journal of Gastroenterology 2022年第37期28卷 5444-5456页

作者： ricardo Ulises Macías-Rodríguez Alberto Adrián Solís-Ortega Victoria J Ornelas-Arroyo Astrid Ruiz-Margáin Maria Sarai González-Huezo nestor A Urdiales-Morán Berenice M román-Calleja Juan M Mayorquín-Aguilar JoséA González-Regueiro Alejandro Campos-Murguía Israel Vicente Toledo-Coronado Mónica Chapa-Ibargüengoitia Bernardo Valencia-Peña Carlos Fernando Martínez-Cabrera nayelli C Flores-García Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico Department of Gastroenterology Centro Médico ISSEMYMToluca 52140Mexico Department of Radiology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico

BACKGROUnD Metabolic associated fatty liver disease(MAFLD)is associated with complications and mortality in patients with coronavirus disease 2019(COVID-19).However,there are no prognostic scores aimed to evaluate the risk of severe disease specifically in patients with MAFLD,despite its high *** dehydrogenase,aspartate aminotransferase and alanine aminotransferase have been used as markers of liver ***,we propose an index based on lactate dehydrogenase,aspartate aminotransferase and alanine aminotransferase for the prediction of complications and mortality in patients with MAFLD and *** To evaluate the prognostic performance of an index based on lactate dehydrogenase and transaminases(aspartate aminotransferase/alanine aminotransferase)in patients with COVID-19 and MAFLD[liver fibrosis and nutrition(LnF)-COVID-19 index].METHODS In this retrospective cohort study,two cohorts from two different tertiary centers were *** first was the derivation cohort to obtain the score cutoffs,and the second was the validation *** included hospitalized patients with severe COVID-19 and *** steatosis was evaluated by computed tomography *** under the receiver operating characteristic(ROC)curve analysis and survival analysis were *** In the derivation cohort,44.6%had MAFLD;ROC curve analysis yielded a LFn-COVID-19 index>1.67 as the best cutoff,with a sensitivity of 78%,specificity of 63%,negative predictive value of 91%and an area under the ROC curve of *** the multivariate analysis,the LFn-COVID-19 index>1.67 was independently associated with the development of acute kidney injury(odds ratio:1.8,95%confidence interval:1.3-2.5,Pntubation(odds ratio:1.9,95%confidence interval:1.4-2.4,Pnd death(odds ratio:2.86,95%confidence interval:1.6-4.5,Pn both *** LFn-COVID-19 index has a good performance to predict prognosis in patients with MAFLD and COVID-19,which

关键词： COVID-19 Metabolic associated fatty liver disease Lactate dehydrogenase Transaminases Prognosis nonalcoholic fatty liver disease

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Efficient metallization of magnetite concentrate by reduction with agave bagasse as a source of reducing agents

引用

International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 603-611页

作者： Diana Cholico-González noemíOrtiz Lara Mario Alberto Sánchez Miranda ricardo Morales Estrella Ramiro Escudero García Carlos ALeón Patiño COnACYT-Metallurgy and Materials Research Institute Michoacana University of San Nicolás de HidalgoMorelia CP 58030Mexico Metallurgy and Materials Research Institute Michoacana University of San Nicolás de HidalgoMorelia CP 58030Mexico

The reduction behavior and metallization degree of magnetite concentrate with agave bagasse were investigated in an inert *** effects of temperature,biomass content,and residence time on reduction experiments and metallization degree were investigated by X-ray diffraction and scanning electron *** with other types of biomass,agave bagasse had lower contents of nitrogen,sulfur,and ash.X-ray diffraction analysis showed that the metallization degree improved with increasing temperature and biomass *** metallization was achieved at 1100℃ for 30 min with 65:35 and 50:50 ratios of the magnetite concentrate to the agave *** results demonstrate that agave bagasse promotes the efficient metallization of magnetite concentrate without the external addition of a reducing ***,this biomass is a technical suitable alternative to replace fossil fuels in steelmaking.

关键词： magnetite concentrate agave bagasse biomass reduction metallization degree

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：