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Hard life for sons in the nest?Sex-dependent offspring mortality in Great Tits in urban and forest areas
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作者 Nora Agh Henriett Anna Dalvári +2 位作者 Krisztián Szabó Ivett Pipoly András Liker 《Avian Research》 SCIE CSCD 2024年第1期91-97,共7页
Sex-biased mortality can occur in birds during development,for example due to sexual differences in energy requirement and/or environmental sensitivity,or the effects of sex hormones or sex differences in the expressi... Sex-biased mortality can occur in birds during development,for example due to sexual differences in energy requirement and/or environmental sensitivity,or the effects of sex hormones or sex differences in the expression of mutations linked to sex chromosomes.The extent of sex-bias in mortality may also be related to environmental conditions that influence offspring development and survival.Urban areas often provide poorer conditions for nestling development resulting in higher offspring mortality compared to natural areas,which may accelerate sex differences in offspring mortality in cities.To test this hypothesis,we examined the sex ratio of dead offspring in Great Tits(Parus major),using 427 samples of unhatched eggs and dead nestlings collected in two urban and two forest sites between 2013 and 2019.The ratio of males in the whole sample of dead offspring(56.9%)was significantly higher than expected by an 1:1 ratio,and the strongest sex biases were detected in urban areas(57.6%males)and in young nestlings(<14 days old,59.0%males).However,the sex ratios of dead offspring did not differ significantly among study sites and between offspring developmental stages.29.3%of unhatched eggs contained a visible embryo,and the proportion of embryo-containing unhatched eggs did not differ significantly between urban and forest study sites.These results suggest male-biased offspring mortality in Great Tits,and highlight the need of large datasets to detect subtle differences between habitats and developmental stages. 展开更多
关键词 great Tit URBANIZATION Nestling mortality Sex related differences
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Trade,Power,and Welfare:An International Economic Political Analysis of Great Power Competition
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作者 Zhang Yuyan Xia Guangtao 《Social Sciences in China》 2024年第3期57-75,共19页
Traditional international trade theories seldom consider the pursuit of power as maintaining and enlarging a country's relative strength in the process of interstate competition.However,in the context of great pow... Traditional international trade theories seldom consider the pursuit of power as maintaining and enlarging a country's relative strength in the process of interstate competition.However,in the context of great power competition,the importance of power in the trade between advanced and latecomer countries has become more pronounced.Given this situation,we can establish a tractable and generalized international economic political framework for analyzing great power competition by introducing the power factor into classic two-country trade theory,treating the absolute welfare and relative welfare emphasized by economics and political science respectively as actors'dual objectives,and making use of game theory methods.It can be found that in a two-country game composed of an advanced and a latecomer country,the latter will prefer a strategy of"enhancing its own strength and rectifying its own weak points,"while the former will favor a strategy that""worsens the other's weak points and enhances the other's strengths."Once the technological gap that determines comparative advantage narrows,the advanced country will tend to totally suppress the latecomer and even"decouple"from it. 展开更多
关键词 great power competition TRADE POWER WELFARE dual efficiency
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Evidence of the Great Attractor and Great Repeller from Artificial Neural Network Imputation of Sloan Digital Sky Survey
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作者 Christopher Cillian O’Neill 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1178-1194,共17页
The Sloane Digital Sky Survey (SDSS) has been in the process of creating a 3D digital map of the Universe, since 2000AD. However, it has not been able to map that portion of the sky which is occluded by the dust gas a... The Sloane Digital Sky Survey (SDSS) has been in the process of creating a 3D digital map of the Universe, since 2000AD. However, it has not been able to map that portion of the sky which is occluded by the dust gas and stars of our own Milkyway Galaxy. This research builds on work from a previous paper that sought to impute this missing galactic information using Inpainting, polar transforms and Linear Regression ANNs. In that paper, the author only attempted to impute the data in the Northern hemisphere using the ANN model, which subsequently confirmed the existence of the Great Attractor and the homogeneity of the Universe. In this paper, the author has imputed the Southern Hemisphere and discovered a region that is mostly devoid of stars. Since this area appears to be the counterpart to the Great Attractor, the author refers to it as the Great Repeller and postulates that it is an area of physical repulsion, inline with the work of GerdPommerenke and others. Finally, the paper investigates large scale structures in the imputed galaxies. 展开更多
关键词 Artificial Neural Networks Convolutional Neural Networks SDSS ANISOTROPIES great Attractor
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Case Report: Surgical Correction of Transposition of the Great Arteries with Aortopulmonary Window
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作者 Qiqi Shi Xuan Lei +1 位作者 Wenbo Zhang Ming Ye 《Congenital Heart Disease》 SCIE 2024年第3期275-278,共4页
Introduction:Transposition of the great arteries(TGA)with aortopulmonary window is a rare type of congenital heart disease with limited experience.We reported a neonate aged 25 days receiving the arterial switch opera... Introduction:Transposition of the great arteries(TGA)with aortopulmonary window is a rare type of congenital heart disease with limited experience.We reported a neonate aged 25 days receiving the arterial switch operation and assisted with extracorporeal membrane oxygenation.Conclusion:TGA with aortopulmonary window can be safely correctly with the arterial switch operation. 展开更多
关键词 Transposition of the great arteries aortopulmonary window arterial switch operation
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A 63-Year-Old Male with D-Transposition of the Great Arteries Who Had an Early Form of the Arterial Switch Operation
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作者 Michael A.Rebolledo Jane S.Yao +2 位作者 Jason N.Johnson Umar S.Boston Benjamin R.Waller III 《Congenital Heart Disease》 SCIE 2024年第1期65-68,共4页
We describe a 63-year-old male who appears to have undergone an early form of the arterial switch operation for D-transposition of the great arteries performed in the mid-1960s.We review the clinical and imaging data ... We describe a 63-year-old male who appears to have undergone an early form of the arterial switch operation for D-transposition of the great arteries performed in the mid-1960s.We review the clinical and imaging data that support our conclusion.He had a diagnostic cardiac catheterization which demonstrated severe pulmonary hypertension responsive to epoprostenol and oxygen.Our case may represent one example of the experimental surgical work done prior to Dr.Adibe Jatene’s description of thefirst successful arterial switch performed in 1975. 展开更多
关键词 Adult congenital heart disease arterial switch operation great vessel anomaly imaging(all modalities)
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Asia-Pacific Security Situation and Strategic Response Under Great Changes
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作者 Zhang Jie 《Contemporary World》 2024年第2期19-23,共5页
Our world today is going through accelerated transformation unseen in a century.The new round of scientific and technological revolution and industrial transformation is gaining steam,the international balance of powe... Our world today is going through accelerated transformation unseen in a century.The new round of scientific and technological revolution and industrial transformation is gaining steam,the international balance of power is undergoing profound adjustment,and China’s development is facing new strategic opportunities. 展开更多
关键词 great STRATEGIC RESPONSE
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Celebrate Chinese New Year with Great Joy
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《China & The World Cultural Exchange》 2024年第1期8-15,共8页
Series of Activities for 2024 Chinese New Year Launched by the Ministry of Cultureand Tourism From January 18 to March 11, the Ministry of Culture and Tourism ofthe People's Republic of China organizes the 2024 Ch... Series of Activities for 2024 Chinese New Year Launched by the Ministry of Cultureand Tourism From January 18 to March 11, the Ministry of Culture and Tourism ofthe People's Republic of China organizes the 2024 Chinese New Yearthemedcultural and tourist activities "Celebrate the Chinese New Year withGreat Joy", which includes 25 main activities in 7 major sections, coveringpeople-benefit art performances, public service activities, demonstration ofintangible cultural heritage experience, tourism and leisure consumption,ice & snow research and tourism, cultural exhibitions, international anddomestic interaction and other fields, with supply of high-quality cultural andtourist products, so as to enrich the holiday life of the people and to meet thepeople's requirements for a happy New Year. 展开更多
关键词 great TOURISM TOURIST
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Consumer Culture in The Great Gatsby
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作者 ZHU Yuan-chen 《Journal of Literature and Art Studies》 2024年第2期124-127,共4页
F.Scott Fitzgerald’s The Great Gatsby successfully portrays the“Jazz Age”.In the early 20th century,the United States transitioned from a production-based society to a consumer-based society,leading to an era of un... F.Scott Fitzgerald’s The Great Gatsby successfully portrays the“Jazz Age”.In the early 20th century,the United States transitioned from a production-based society to a consumer-based society,leading to an era of unparalleled prosperity.However,in the context of consumer culture,individuals often transition from being masters of their possessions to becoming enslaved by them.As a result,their behaviours and values become increasingly associated with extravagance and consumption.This paper uses Baudrillard’s theory of consumer society and textual analysis to explore the impact of consumer culture on human beings through the symbolization of men and objectification of women in The Great Gatsby.The meanings embedded in the novel are revealed from a different perspective. 展开更多
关键词 consumer culture SYMBOLS OBJECTIFICATION The great Gatsby
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Spatial-temporal distribution and geochemistry of highly evolved Mesozoic granites in Great Xing’an Range,NE China:Discriminant criteria and geological significance
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作者 WU Haoran YANG Hao +4 位作者 GE Wenchun JI Zheng DONG Yu JING Yan JING Jiahao 《Global Geology》 2024年第1期20-34,共15页
Highly evolved granite is an important sign of the mature continent crust and closely associated with deposits of rare metals.In this work,the authors undertake systematically zircon U-Pb ages and whole rock elemental... Highly evolved granite is an important sign of the mature continent crust and closely associated with deposits of rare metals.In this work,the authors undertake systematically zircon U-Pb ages and whole rock elemental data for highly evolved granitic intrusions from the Great Xing’an Range(GXR),NE China,to elucidate their discriminant criteria,spatial-temporal distribution,differentiation and geodynamic mecha-nism.Geochemical data of these highly evolved granites suggest that high w(SiO_(2))(>70%)and differentiation index(DI>88)could be quantified indicators,while strong Eu depletion,high TE_(1,3),lowΣREE and low Zr/Hf,Nb/Ta,K/Rb could only be qualitative indicators.Zircon U-Pb ages suggest that the highly evolved gran-ites in the GXR were mainly formed in Late Mesozoic,which can be divided into two major stages:Late Ju-rassic-early Early Cretaceous(162-136 Ma,peak at 138 Ma),and late Early Cretaceous(136-106 Ma,peak at 126 Ma).The highly evolved granites are mainly distributed in the central-southern GXR,and display a weakly trend of getting younger from northwest to southeast,meanwhile indicating the metallogenic potential of rare metals within the central GXR.The spatial-temporal distribution,combined with regional geological data,indicates the highly evolved Mesozoic granites in the GXR were emplaced in an extensional environ-ment,of which the Late Jurassic-early Early Cretaceous extension was related to the closure of the Mongol-Okhotsk Ocean and roll-back of the Paleo-Pacific Plate,while the late Early Cretaceous extension was mainly related to the roll-back of the Paleo-Pacific Plate. 展开更多
关键词 highly evolved granite great Xing’an Range spatial-temporal distribution extensional environment
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Exploring the Path of Party Building Leading League Construction in Colleges and Universities under the Pattern of Great Ideological and Political Education
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作者 Yi SHENG Tao LI 《Asian Agricultural Research》 2024年第5期42-46,共5页
In accordance with the pattern of"great ideology and politics",the Party and youth League organizations assume the role of vanguard in the organization of colleges and universities.Simultaneously,they serve ... In accordance with the pattern of"great ideology and politics",the Party and youth League organizations assume the role of vanguard in the organization of colleges and universities.Simultaneously,they serve as a pivotal force in ideological and political education.In order to construct a comprehensive ideological and political framework encompassing the entire educational process,it is of paramount importance to identify an efficacious methodology for Party building leading League construction.This paper employs a comprehensive analysis to elucidate the pivotal role of Party building leading League construction in facilitating ideological and political education.It also illuminates the practical challenges encountered in the implementation of Party building leading League construction initiatives within colleges and universities.The article proposes a specific path for Party building leading League construction in colleges and universities based on three key aspects:cohesion of the consensus of Party building leading League building,establishment of the institutional system of Party building leading League construction,and creation of the model brand of Party building leading League construction.The aim is to promote in-depth development of Party building in colleges and universities and enhance the quality and effect of ideological and political education. 展开更多
关键词 great ideological and political education pattern Party building in universities and colleges Party building leading League construction
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New Quality,Great Potential
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作者 XU GANG 《ChinAfrica》 2024年第4期18-21,共4页
Here are some of the achievements China made in 2023:GDP exceeded 126 trillion yuan($17.43 trillion)with a growth of 5.2 percent;12.44 million new urban jobs were created;average surveyed unemployment rate in urban ar... Here are some of the achievements China made in 2023:GDP exceeded 126 trillion yuan($17.43 trillion)with a growth of 5.2 percent;12.44 million new urban jobs were created;average surveyed unemployment rate in urban areas was 5.2 percent;consumer price index increased by 0.2 percent;new energy vehicle production and sales accounted for more than 60 percent of the global share;grain output reached a record high of 695 billion kg;installed renewable energy capacity surpassed thermal power capacity for the first time in history,and China accounted for over half of newly installed renewable energy capacity worldwide;per-capita disposable income of residents increased by 6.1 percent… 展开更多
关键词 INCOME installed great
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Africa’s Grand Walk to Greatest Tomorrow
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作者 ABISAI TEMBA 《ChinAfrica》 2024年第1期64-64,共1页
The book initiates by portraying Africa,introducing its physical features and endowments,and providing a concise historical perspective that highlights Africa as the initial home of the human species.Subsequently,the ... The book initiates by portraying Africa,introducing its physical features and endowments,and providing a concise historical perspective that highlights Africa as the initial home of the human species.Subsequently,the book explores another epoch in Africa’s self-consciousness,focusing on the Pan-Africanism in the middle of the 20th century-the time when Africa had been greatly subjected to imperialism and colonialism,which plunged it into great destitution. 展开更多
关键词 GRAND AFRICA great
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Recent Vegetation Cover Dynamics and Climatic Parameters Evolution Study in the Great Green Wall of Senegal 被引量:1
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作者 Bi Tra Olivier Gore Angora Aman +1 位作者 Yves Kouadio Ody-Marc Duclos 《Journal of Environmental Protection》 CAS 2023年第4期254-284,共31页
The drought recorded in 1970s and 1980s, particularly in the Sahara and Sahel region has greatly affected the population as well as the economies and the eco-systems of this area. In 2007, the African Union launched a... The drought recorded in 1970s and 1980s, particularly in the Sahara and Sahel region has greatly affected the population as well as the economies and the eco-systems of this area. In 2007, the African Union launched a Pan-African program, the Great Green Wall for the Sahara, the Sahel Initiative (GGWSSI) to reverse land degradation and desertification by planting a wall of trees stretching from Dakar to Djibouti. The objective is to improve food security, and support local people to adapt to climate change. This paper aims to evaluate the impacts of the reforestation program in Senegal, fifteen years after it was launched. This study uses a time series of satellite-derived vegetation cover and climatic parameters data to analyze the sustainability of these interventions. Change detection approaches were applied to identify and characterize the drives of the eventual changes. A comparative analysis of reforestation on climatic parameters was explored through the temporal analysis of the vegetation index over the periods 2000-2008 and 2009-2020. An increase in vegetation activity was noted through the NDVI at the interannual (+2% to +8%) and seasonal (+1.5% to 7% for the wet season and 1% to 4% for the dry season) scale and a positive and significant evolution is noted on the trace of the GGW. Also, the period 2009-2020 recorded an increase in rainfall of 2% to 8% of the average value 2000-2020 and 4% to 8% of the rainy season. Soil moisture is the climatic parameter that has increased the most, with an increase of 25% to 54% of the 2000-2020 average, i.e. between 20 mm and 70 mm more. This study shows a significant improvement in the relationship between NDVI and climate parameters after the different reforestation actions of the GGW. 展开更多
关键词 great Green Wall of Senegal Vegetation Index PRECIPITATION Soil Moisture
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地质科学新思维观与新时代地质工作战略思考 被引量:2
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作者 施俊法 吴林强 +4 位作者 王泉 方圆 杨宗喜 姚晓峰 贾德龙 《中国地质》 CAS CSCD 北大核心 2024年第2期547-560,共14页
【研究目的】通过分析新时代地质工作面临的挑战和机遇,构建地质科学新思维观,力求使地质工作健康、持续、稳定发展。【研究方法】从理论与实践、历史与未来、守正与创新、发展与保护的逻辑出发,研究提出地质科学新思维观,并分析其意义... 【研究目的】通过分析新时代地质工作面临的挑战和机遇,构建地质科学新思维观,力求使地质工作健康、持续、稳定发展。【研究方法】从理论与实践、历史与未来、守正与创新、发展与保护的逻辑出发,研究提出地质科学新思维观,并分析其意义。【研究结果】地质科学新思维观主要是:(1)地质大基础观,加强区域基础地质调查,加强全国资源、环境、生态、灾害、空间国情调查,深化对地球认知的水平。(2)地质大资源观,将全部地质要素进行整体调查、开发与保护,实现各类地质要素资源综合效益的最大化。能源和战略性矿产是最核心的地质资源,地质工作要把保障国家能源和战略性矿产资源安全摆在首位。(3)地质大生态观,发挥地质工作在促进生态系统稳定与可持续中的作用,解决生态系统问题或维护生态系统功能。(4)地质大数据观,充分运用现代信息技术,全面实现地质工作的数字化、智能化转型。(5)地质大系统观,将地球与自然、社会、经济系统作为整体综合考虑,维持地球系统稳定和人类经济社会可持续发展,推进传统地质科学向地球系统科学转变。【结论】基于新思维观,新时代地质工作要:树立地质大基础观,提高基础地质调查水平,深化对地球发展演化的认知;树立地质大资源观,巩固传统地质找矿工作,实现新一轮找矿取得重大突破,拓展自然资源调查评价新领域;树立地质大生态观,开辟生态地质,为生态修复与保护提供地质解决方案;树立地质大数据观,构建地质科学研究新范式,为社会需求提供智慧化地质解决方案;树立地质大系统观,发展和完善地球系统科学,建立新一代地质科学知识体系。 展开更多
关键词 矿产勘查 生态文明 地质大基础观 地质大资源观 地质大生态观 地质大数据观 地质大系统观
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An analysis of Great Salt Lake Winogradsky columns
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作者 Sierra A.DE LEON Anna E.JACKSON +4 位作者 William BLACK William THOMAS Matt KRUBACK June BAXTER Bonnie K.BAXTER 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1352-1368,共17页
Sergei Winogradsky illuminated revolutionary concepts and produced a tool to visualize complex microbial communities and their metabolisms over time:columns displaying aquatic consortia with variety of niches.We worke... Sergei Winogradsky illuminated revolutionary concepts and produced a tool to visualize complex microbial communities and their metabolisms over time:columns displaying aquatic consortia with variety of niches.We worked with museums in Utah to create Winogradsky columns that would highlight aesthetic properties of the Great Salt Lake(GSL)ecosystem,which has a salinity gradient from the freshwater wetlands to salt saturation.One column,constructed using haloarchaea-rich hypersaline brine and oolitic sand of the lake’s north arm,was enriched with nutrients,and resulted in the desired pink hue over time.After a seven-year maturation period,we examined the microbial taxa present in the water through 16 S/18 S rRNA and Internal Transcribed Spacer(ITS)gene sequencing.A pigment analysis revealed an abundance of bacteriochlorophyll a.The presence of this pigment coupled with the DNA sequencing results,suggest that the haloarchaea that dominate the GSL brine,were not responsible for the pink coloration,but instead Gammaproteobacteria,especially Halorhodospira species.Among the eukaryotes,the lack of phytoplankton and the abundance of fungi were noteworthy observations.These data likely relate to the reduction of oxygen in a non-aerated sealed system over time.Our second exhibit had the goal of educating museum goers about the varying salinities of Great Salt Lake.Here we employed three distinct columns of water and sediment from this salinity gradient.Observations of these columns overtime gave us information about invertebrate communities in addition to the microbial consortia.Both installations taught us about comparing an artificial environment in a museum setting to the natural ecosystem.Taken together,we present the data collected and lessons learned from using Winogradsky columns in public spaces for teaching about an important saline lake. 展开更多
关键词 great Salt Lake Winogradsky HALOPHILES extreme environment museum exhibit
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A Comparison of Two Macroinvertebrate Multi-Plate Sampling Methods to Inform Great Lakes Monitoring and Remediation Efforts
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作者 Roger Yeardley Brian Duffy +3 位作者 Kimani Kimbrough Jim Lazorchak Marc A. Mills Ed Johnson 《Journal of Environmental Protection》 2023年第12期933-953,共21页
Hester-Dendy (HD) multi-plate samplers have been widely used by state and federal government agencies for bioassessment of water quality through use of macroinvertebrate community data. To help guide remediation and r... Hester-Dendy (HD) multi-plate samplers have been widely used by state and federal government agencies for bioassessment of water quality through use of macroinvertebrate community data. To help guide remediation and restoration efforts at the Niagara River Great Lakes Area of Concern site, a multi-agency study was conducted in 2014 to assess the contribution of seven major urban tributaries on the US side of the river toward the impairment of the Niagara River. As part of this study, macroinvertebrate communities were sampled using two co-located versions of HD samplers: one version used by the New York State Department of Environmental Conservation (NYSDEC) and another by the US Environmental Protection Agency Office of Research and Development. Samplers were deployed in tributaries in highly developed watersheds with high percent impervious surface. The two sampling methods varied in terms of number and size of plates, between-plate spacing, and deployment method. Comparison of the similarity/grouping of communities with multivariate ordination techniques, Nonmetric Multidimensional Scaling and Multi-Response Permutation Procedure, showed that both methods were able to detect differences in communities at stations, despite some grouping by month and method. The indices and metrics derived from the two HD methods were found to give comparable but not identical assessments of water quality. Despite their differences, the methods were robust with respect to water quality categories derived from indices used nationally (HBI) and by NY state (BAP). For the common richness metrics, total taxa and EPT richness, there was no statistical difference between means from 3 samplings. Some metrics, especially percent tolerant collector-gatherer individuals, did show significant differences at certain stations. Indicator Species Analysis showed some taxa associated with each method. The observed community differences were thought mostly due to the difference in sampler deployment position. . 展开更多
关键词 Hester-Dendy Multi-Plate Samplers MACROINVERTEBRATE BIOASSESSMENT great Lakes Methods Area of Concern
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Digital Healthcare Industry Ushered in Great Opportunities
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作者 Audrey Guo 《China's Foreign Trade》 2023年第3期51-53,共3页
In recent years,as the digital economy continuously booms,digital technologies such as 5G,cloud computing,big data,tele-medicine and artificial intelligence are developing rapidly and being deeply integrated with vari... In recent years,as the digital economy continuously booms,digital technologies such as 5G,cloud computing,big data,tele-medicine and artificial intelligence are developing rapidly and being deeply integrated with various application scenarios,which gradually turn into an important driver for economic innovation and development.As one of the scenarios closest to the social economy and people’s lives,the increasingly digitalized healthcare industry,namely digital healthcare,is receiving more and more attention. 展开更多
关键词 ECONOMY great continuously
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Geochronology and Geochemistry of Early Cretaceous A-type Granites in Central-Eastern Inner Mongolia,China:Implications for Late Mesozoic Tectonic Evolution of the Southern Great Xing'an Range
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作者 ZHANG Yanwen ZHANG Xiaofei +6 位作者 CHEN Lixin PANG Zhenshan CHEN Hui XUE Jianling ZHOU Yi TENG Chao CHEN Guochao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1094-1111,共18页
The southern Great Xing'an Range is the most critical Sn-polymetallic metallogenic belt in northeast China.However,the tectonic setting of the Early Cretaceous magmatic-metallogenic”flare-up“event remains uncert... The southern Great Xing'an Range is the most critical Sn-polymetallic metallogenic belt in northeast China.However,the tectonic setting of the Early Cretaceous magmatic-metallogenic”flare-up“event remains uncertain.This paper presents an integrated study on the occurrence,petrology,zircon U-Pb ages,whole-rock geochemistry,and in situ zircon Hf isotopes for Wenduerchagan granites of Xi Ujimqin Banner,central-eastern Inner Mongolia.These granites consist primarily of granite porphyry(with ages of 137±1 Ma and 138±1 Ma)and(porphyritic)alkali feldspar granite(with an age of 141±2 Ma),corresponding to the early Early Cretaceous.They are A-type granites characterized by high silicon,alkali,and TFeO/MgO contents while being depleted of Ba,Nb,Ta,Sr,P,and Ti.They show right-dipping trend rare-earth element distribution characteristics with negative Eu anomalies(Eu/Eu^(*)=0.01-0.20)and weak heavy rare-earth element fractionation((Gd/Yb)_(N)=0.77-2.30).They demonstrate homogeneous zircon Hf isotopic compositions(positiveε_(Hf)(t)values from+5.3 to+7.1 and young two-stage Hf model ages of 851-742 Ma)and high zircon saturation temperatures(av.810℃).These geochemical characteristics indicate that Wenduerchagan granites originated from the partial melting of juvenile crust under high-temperature and low-pressure conditions.Wenduerchagan granites most likely formed in a post-collisional compression-extension transition regime caused by the closure of the Mongol-Okhotsk Ocean,when combined with regional geology.Such a transition regime can probably be attributed to the upwelling of the asthenospheric mantle caused by the break-off of a subducted Mongol-Okhotsk oceanic slab.Upwelling asthenospheric mantle provided sufficient energy and favorable tectonic conditions for magmatism and mineralization of the Early Cretaceous. 展开更多
关键词 magmatism and mineralization A-type granite post-collisional environment Early Cretaceous southern great Xing'an Range Mongol-Okhotsk Ocean
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Endovenous laser treatment vs conventional surgery for great saphenous vein varicosities: A propensity score matching analysis
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作者 Qiang Li Chen Zhang +2 位作者 Zhao Yuan Zi-Qi Shao Jian Wang 《World Journal of Clinical Cases》 SCIE 2023年第35期8291-8299,共9页
BACKGROUND Varicosis is a common venous condition,which is typically treated surgically.However,selection of the optimal surgical approach can be challenging.Previous studies comparing endovenous laser treatment(EVLT)... BACKGROUND Varicosis is a common venous condition,which is typically treated surgically.However,selection of the optimal surgical approach can be challenging.Previous studies comparing endovenous laser treatment(EVLT)and conventional surgery were retrospective and observational in nature and the results may therefore have been influenced by selection bias and the presence of other confounding factors.In this study,we used propensity score matching to reduce selection bias when comparing EVLT and conventional surgery for the treatment of varicose great saphenous veins.METHODS We retrospectively reviewed the records of 1063 patients treated for primary varicosis of the great saphenous vein at the Second Affiliated Hospital of Xuzhou Medical University between January 2009 and December 2019.Among them,56 patients were excluded owing to additional small saphenous varicose vein involvement,81 owing to recurring varicose veins,83 owing to complicated varicose veins(CEAP clinical classification C5-C6),and 6 owing to perioperative phlebitis.Finally,772 patients were enrolled in this study.Standard demographic and clinicopathological data were collected from the medical records of the patients.For propensity score matching,522 patients(261 who underwent EVLT and 261 who underwent conventional surgery)were randomly matched 1:1 by age,sex,onset time,smoking status,presence of diabetes,family history,stress therapy,C class,and the affected leg.RESULTS Of the 772 patients included in the study,467 underwent EVLT and 305 underwent conventional surgery.There were significant differences in age,onset time,smoking and diabetes status,and family history between the two groups.Following propensity score matching,no significant differences in patients’characteristics remained between the two groups.ELVT was associated with a shorter operation time and hospital stay than conventional surgery,both before and after propensity score matching.There were no differences in complications between the two groups after propensity score matching.Patients who underwent EVLT had a higher recurrence rate during the two-year follow-up period than those who underwent conventional surgery(33.33%vs 21.46%,χ^(2)=11.506,P=0.001),and a greater percentage of patients who underwent EVLT experienced pain one week after the procedure(39.85%vs 19.54%,P=0.000).CONCLUSION EVLT may not always be the best option for the treatment of great saphenous vein varicosis. 展开更多
关键词 Endovenous laser treatment Conventional surgery great saphenous vein Propensity score matching OUTCOMES Varicosis
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Estimation of the Carbon Sequestration Dynamics of Senegal’s Great Green Wall Based on Land Cover over the Past Three Decades
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作者 Bi Tra Olivier Gore Angora Aman +2 位作者 Yves K. Kouadio Ody-Marc Duclos Kazunao Sato 《Journal of Environmental Protection》 2023年第12期954-983,共30页
The severe drought observed in the Sahel during 1970s, 1980s and 1990s has deeply affected the population as well as the economies and the eco-systems of this climatic area. The GGW Initiative spearheaded by Africa Un... The severe drought observed in the Sahel during 1970s, 1980s and 1990s has deeply affected the population as well as the economies and the eco-systems of this climatic area. The GGW Initiative spearheaded by Africa Union in 2007 proposed to combat the land degradation and desertification by planting a wall of trees stretching from Dakar to Djibouti. A reforestation was then conducted in the Senegal’s GGW since 2006 as part as other areas in the Sahel. This paper aims to evaluate the carbon sequestration dynamics in the sites of the Senegal’s GGW over the last three decades. The method consists firstly of analyzing the evolution of land cover and land use dynamics based on ESA-CCI LC satellite data. There is an improvement of the surface areas of tree and shrub savanna of 11.40% (Tessekere), 8.25% (Syer) and 2.70% (Loughere-Thioly). The regreening of the different localities and a positive dynamic observed is explained by the return to normal rainfall and to reforestation actions, agroforestry practices, better management of natural resources undertaken. However, some non-reforested sites showed an opposite trend despite of the normal rainfall. Secondly, the results on land mapping are used as a proxy for the assessment of carbon stocks. The dynamic observed in vegetation cover since the beginning of the reforestation made it possible to sequester 5.8 million tons of carbon representing respectively 2.31% of African GGW. This gain in stored carbon is equivalent to 21.2 million tons of CO<sub>2</sub> captured in the atmosphere. Through this study, it appears that carbon storage becomes significant 8 to 10 years after the start of reforestation. An urbanization without respect for the environmental factors could be a danger for the climate (case of Ballou). 展开更多
关键词 great Green Wall of Senegal Land Cover-Land Use (LCLU) Carbon Storage
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