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Research on the Integration of Lingnan Culture into“Four Histories”Education for Hong Kong Youth
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作者 Hua Wang 《Journal of Contemporary Educational Research》 2024年第10期263-270,共8页
This study focuses on Hong Kong youth,recognizing them as a vital subject within the context of“four histories”education.From the perspective of the integration of Lingnan culture,it explores the rich resources of L... This study focuses on Hong Kong youth,recognizing them as a vital subject within the context of“four histories”education.From the perspective of the integration of Lingnan culture,it explores the rich resources of Lingnan culture,innovates the narrative system,and explores the path of positive guidance in history education.Responding to the demands of the times,it seeks to alleviate the pressing concerns of Hong Kong society,help Hong Kong youth break down prejudices,gain a comprehensive understanding of China,grasp the development context of modern China,recognize historical trends,undertake national responsibilities,and take on the mission of the times. 展开更多
关键词 Lingnan culture Hong Kong youth “Four histories”education
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Comparison of brain functions between healthy participants and methamphetamine users with various addiction histories:Data analysis based on EEG and fNIRS
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作者 Xuelin Gu Xiaoou Li Banghua Yang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第3期41-55,共15页
The electroencephalogram(EEG)rhythm and functional near-infrared spectroscopy(fNIRS)activation levels have not been compared between a healthy control group(HCG)and methamphetamine user group(MUG)with different addict... The electroencephalogram(EEG)rhythm and functional near-infrared spectroscopy(fNIRS)activation levels have not been compared between a healthy control group(HCG)and methamphetamine user group(MUG)with different addiction histories.This study used 64-electrode EEG and fNIRS to conduct an experiment that analyzed the resting and craving states.The EEG and fNIRS data of 56 participants were collected,including 14 healthy participants,14 methamphetamine users with an addiction history of 0.5–5 years,14 users with an addiction history of 5–10 years,and 14 users with an addiction history of 10–15 years.Isolated effective coherence(iCoh)within the brain network was used to process the EEG data.Statistical analysis was performed to compare differences in iCoh among the delta,theta,alpha,beta,and gamma bands and explore oxyhemoglobin activation levels in the ventrolateral prefrontal cortex,dorsolateral prefrontal cortex,orbitofrontal cortex,and frontopolar prefrontal cortex(FPC)of the control group.Finally,the Kmeans,Gaussian mixed model(GMM),linear discriminant analysis(LDA),support vector machine(SVM),Bayes,and convolutional neural networks(CNN)algorithms were used to classify methamphetamine users based on drug and neutral images.A 3-class accuracy was achieved.Changes in EEG and fNIRS activation levels of HCG and MUG with varied addiction histories were demonstrated. 展开更多
关键词 Drug addiction history ELECTROENCEPHALOGRAM functional near-infrared spectroscopy isolated effective coherence addiction history classification
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Effects of Life Histories on Genome Size Variation in Squamata
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作者 Chuan CHEN Long JIN +1 位作者 Ying JIANG Wenbo LIAO 《Asian Herpetological Research》 SCIE CSCD 2021年第3期289-294,共6页
Genome size changes significantly among taxonomic levels,and this variation is often related to the patterns shaped by the phylogeny,life histories and ecological factors.However,there are mixed evidences on the main ... Genome size changes significantly among taxonomic levels,and this variation is often related to the patterns shaped by the phylogeny,life histories and ecological factors.However,there are mixed evidences on the main factors affecting molecular evolution in animals.In this study,we used phylogenetic comparative analysis to investigate the evolutionary rate of genome size and the relationships between genome size and life histories(i.e.,hatchling mass,clutch size,clutches per year,age at sexual maturity,lifespan and body mass)among 199 squamata species.Our results showed that the evolutionary rate of genome size in Lacertilia was significantly faster than Serpentes.Moreover,we also found that larger species showed larger hatchling mass,more clutches per year and clutch size and longer lifespan.However,genome size was negatively associated with clutch size and clutches per year,but not associated with body mass we looked at.The findings suggest that larger species do not possess the evolution of large genomes in squamata. 展开更多
关键词 genome size body mass evolutionary rate life histories
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THE CHANGE IN CARTIMANDUA'S CHARACTER IN ANNALS 12.40 AND HISTORIES 3.45
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作者 James J.Stewart 《Journal of Ancient Civilizations》 2001年第1期93-100,共8页
关键词 THE CHANGE IN CARTIMANDUA’S CHARACTER IN ANNALS 12.40 AND histories 3.45
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Spatially Different Nutrient Histories Recorded by Multiple Cores and Implications for Management in Taihu Lake, Eastern China 被引量:4
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作者 CAO Yanmin ZHANG Enlou +2 位作者 Peter LANGDON LIU Enfeng SHEN Ji 《Chinese Geographical Science》 SCIE CSCD 2013年第5期537-549,共13页
The Taihu Lake,a large shallow lake in the floodplain of the Changjiang(Yangtze) River in the eastern China,is faced with challenging ecological problems resulting from eutrophication,which has affected the regional f... The Taihu Lake,a large shallow lake in the floodplain of the Changjiang(Yangtze) River in the eastern China,is faced with challenging ecological problems resulting from eutrophication,which has affected the regional freshwater supply of a large population.Although efforts have been made to assess the nutrient evolution histories in the northern bays,little is known regarding nutrient histories in different parts across the entire lake basin.In this paper,we present nutrient histories for different parts of the lake based on chironomid transfer functions applied to four short cores obtained from the northern,western and eastern regions of the lake.The chironomid-inferred total phosphorus(CI-TP) concentrations were compared with the phosphorus concentrations obtained by using instrumental and sedimentary data.The results suggest that trophic evolution histories were asynchronous throughout the lake during the past decades in response to different ecological regimes controlled by the nutrient input,wind direction and shoreline topography.The restoration of aquatic plants may be an effective option for the management of lake rehabilitation to ′natural′ conditions.Given the multiple factors controlling the biotic communities in such a large and complex lake,combined analyses among the multi-proxies encountered in the sediments are necessary for comprehensive insight into paleolimnological studies.The spatial heterogeneity in the ecological trajectories within this complicated ecosystem suggests that different management practices should be undertaken for specific lake zones in the Taihu Lake. 展开更多
关键词 nutrient history CHIRONOMID multiple cores transfer function Taihu Lake
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The Silk Road(丝绸之路)and Sources of Chinese Medicine Expansion: Part Ⅲ-Histories 被引量:1
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作者 Sean Bradley 《Chinese Medicine and Culture》 2019年第1期29-31,共3页
Medicine and knowledge of medical practice have been exchanged along the Silk Road since antiquity.Medical texts provide the vast majority of information about the drugs,techniques,and ideas that passed from foreign l... Medicine and knowledge of medical practice have been exchanged along the Silk Road since antiquity.Medical texts provide the vast majority of information about the drugs,techniques,and ideas that passed from foreign lands into China and became part of Chinese medicine.In addition to the medical corpus,historical works provide the backdrop for how,when,and from where these ideas and medicines entered and influenced Chinese medical practice.Examining the historical texts and the information pertaining to medical exchange can allow us to better understand how foreign cultures and practices of medicine along the Silk Road entered and influenced Chinese Medicine. 展开更多
关键词 Chinese medicine HISTORY Silk Road(丝绸之路) transfer of medicine
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Otolith Microstructure Analysis Reveals Different Growth Histories of Japanese Sardine (Sardinops melanostictus) in the Oyashio Waters
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作者 LIU Chunlin ZHANG Chi +4 位作者 TIAN Yongjun WANG Liangming LIN Longshan LI Yuan WATANABE Yoshiro 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第1期236-242,共7页
After decades of low year classes,the stock of Japanese sardine(Sardinops melanostictus)has begun to recover since the mid-2000s.The hatch dates and otolith growth rates of age-0 juvenile sardine,which were collected ... After decades of low year classes,the stock of Japanese sardine(Sardinops melanostictus)has begun to recover since the mid-2000s.The hatch dates and otolith growth rates of age-0 juvenile sardine,which were collected in the subarctic Oyashio waters in autumn 2018,were determined from an otolith microstructure analysis.The sardines were hatched from late January to late April,while mostly in February and March.The otolith growth rate increased continuously up to 60 d after hatching and thereafter de-creased.The revealed growth rate in a crucial growth period is faster than that reported for juvenile sardines collected in the 1990s,which is coincided with the recent recovery trend of the sardine stock.Two groups with different hatch dates,growth histories,and migration routes were identified using unsupervised random forest clustering analysis.They were considered inshore and offshore migration individuals in accordance with recent researches.In the offshore group,a high proportion of sardine juveniles hatched late and grew faster in the Kuroshio-Oyashio transitional waters,a finding consistent with the hypothesis of growth-rate-dependent re-cruitment.This finding on the population composition and growth rate of juvenile sardine in the Oyashio waters can be a basis for an improved prediction of their survival and provides us with valuable information on the recruitment processes of this stock during the period of stock recovery. 展开更多
关键词 Sardinops melanostictus otolith microstructure growth history unsupervised random forest clustering RECRUITMENT
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A COMPARATIVE STUDY ON THE CARTOGRAPHIC HISTORIES BETWEEN CHINA AND THE WEST
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作者 Lu Huancheng (Department of Geography, Siping Teachers’ College, Jilin 13600 People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1996年第2期89-96,共8页
Analysis of space shifting of geodetic center of China and the West,reveals that the China's geodetic center has been in coincidence with its political center. Furthermore the development of the maps in Europe was... Analysis of space shifting of geodetic center of China and the West,reveals that the China's geodetic center has been in coincidence with its political center. Furthermore the development of the maps in Europe was controlled by developmat of economy. Thereupon, maps in China and the West were developing in their own ways, and thus formed two different cartographic systems.Although China has a splendid cartogrphic history, it has not yet got many great breakthroughs. The reasons are as follows : 1. The theory of round earth has never occupied the ruling place, instead, the theory of flat earth took the dominant position. Thus the geodetic frameworks of China are not scientific. 2. Owing to the trammels of the theory that China is the whole earth, the Chinese geodetic workers have been limited in China's area. 3. Exchange between the East and the Weat is too late. The Chinese geodetic workers took a long time to accept the West geodetic technology. on the contrary, the West has absorbed the geodetic technology and results of China. 4. China's anciat gcodotic workers usually stopped after getting a little knowledge of a subject. They should have made great breakthroughs in geodetic area. Nevertheless, they failed. 展开更多
关键词 cartographic history theory of flat earth geodetic center
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The Effect of Food Images on Mood and Arousal Depends on Dietary Histories and the Fat and Sugar Content of Foods Depicted
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作者 Gregory J. Privitera Danielle E. Antonelli Heather E. Creary 《Journal of Behavioral and Brain Science》 2013年第1期1-6,共6页
Background: While brain imaging studies show that reward regions in the human brain that regulate reward-guided behavior and integrate sensory modalities of smell, taste, and texture respond preferentially to high cal... Background: While brain imaging studies show that reward regions in the human brain that regulate reward-guided behavior and integrate sensory modalities of smell, taste, and texture respond preferentially to high calorie foods, few studies account for dietary histories or account for recent behavioral evidence showing preferential responding for fruits (a low calorie food that tastes sweet). To address these concerns, the present study tested the hypothesis that images of high/low fat and sugar foods, even sugary foods that are low calorie (i.e., fruits), will enhance emotional responsiveness and that these changes may be related to dietary histories with fat and sugar intake. Method: Participants were shown 4 sets of 15 food images with each food image automatically timed every 9 s to transition to a new food image;participant pre-post mood and arousal was measured. The 4 sets of food images were high fat-high sugar (HFHS;desserts), high fat-low sugar (HFLS;fried foods), low fat-high sugar (LFHS;fruits), or low fat-low sugar (LFLS;vegetables) foods. To account for dietary histories, participants also completed estimated daily intake scales (EDIS) for sugar and fat. Results: Mood and arousal significantly increased in all groups, except Group LFLS, and even in a group that was low calorie but shown foods that taste sweet, i.e., Group LFHS. Interestingly, changes in arousal, but not mood, were dependent on participant histories with sugar and fat intake. Conclusion: Changes in emotional responsiveness to food images were nutrient-specific, which can be a more detailed level of analysis for assessing responsiveness to food images. Also, participant histories with sugar and fat should be taken into account as these histories can explain the changes in arousal observed here. 展开更多
关键词 FAT SUGAR MOOD AROUSAL DIETARY History
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Envelope Functions of Time Histories in Seismic Safety Evaluation and Scenario Earthquakes
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作者 Shen Jianwen Yu Zhan Shi Shuzhong 《Earthquake Research in China》 2008年第3期297-303,共7页
It has been a period of time since the concept of scenario earthquake was proposed, but this concept has rarely been used in seismic safety evaluation in China since then. Meanwhile, because of the uncertainties of ma... It has been a period of time since the concept of scenario earthquake was proposed, but this concept has rarely been used in seismic safety evaluation in China since then. Meanwhile, because of the uncertainties of magnitudes-distances pairs, there is large arbitrariness while determining the envelope function of time histories in seismic hazard analysis. In this paper, we describe a method to control the envelope functions of the time histories by introducing the most-likely combinations of magnitude and distance of the scenario earthquakes based on a probabilistic method, revise the software of the ellipse model for seismic hazard analysis, and give a computation example. 展开更多
关键词 Scenario earthquake Envelope functions of time history Seismic hazard analysis
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The Many Facets of History:A Study on the Accounts of the Dunkirk Evacuation
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作者 DU Xing-chi 《Journal of Literature and Art Studies》 2024年第6期404-409,共6页
This paper adopts a New Historicism approach to examine the shaping of the history of the Dunkirk evacuation through an analysis of Winston Churchill’s historic speech We Shall Fight on the Beaches,Ian McEwan’s nove... This paper adopts a New Historicism approach to examine the shaping of the history of the Dunkirk evacuation through an analysis of Winston Churchill’s historic speech We Shall Fight on the Beaches,Ian McEwan’s novel Atonement,and Christopher Nolan’s film Dunkirk.The research reveals that by uncovering and representing the neglected stories of marginalized groups in Atonement and Dunkirk,new evidentiary threads both enrich and contest the History embodied in Churchill’s speech.Consequently,these alternative accounts both challenge and complement the prevailing historical discourse. 展开更多
关键词 Dunkirk evacuation The History histories
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Impacts of Early Pleistocene glacial vicariance among refugial lineages and Mid-Late Pleistocene interglacial dispersal and expansion on forging population genetic structure of the giant clam Tridacna squamosa(Bivalvia:Cardiidae:Tridacninae)across the Red Sea and Indo-West Pacific oceans
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作者 Temim Deli 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第8期111-127,共17页
This study aims at identifying the microevolutionary processes responsible for the onset of the remarkable phylogeographic structure already recorded for the endangered giant clam Tridacna squamosa across its distribu... This study aims at identifying the microevolutionary processes responsible for the onset of the remarkable phylogeographic structure already recorded for the endangered giant clam Tridacna squamosa across its distribution range.For this purpose,the evolutionary,biogeographic and demographic histories of the species were comprehensively reconstructed in a mitochondrial dataset comprising nearly the whole available published cytochrome c oxidase 1 gene sequences of T.squamosa.Relatively higher level of genetic diversification was unveiled within T.squamosa,in comparison to earlier macro-geographic investigations,whereby five mitochondrial clusters were delineated.The resulting divergent gene pools in the Red Sea,western Indian Ocean,Indo-Malay Archipelago and western Pacific were found to be driven by Early Pleistocene glacial vicariance events among refugial lineages.Accentuated genetic diversification of the species across the Indo-Malay Archipelago was successively triggered by historical dispersal event during the Mid-Pleistocene MIS19c interglacial.This latter historical event might have also enabled genetically distinct giant clams from the Indo-Malay Archipelago to subsequently colonize the western Pacific,accounting for the genetic diversity hotspot detected within this region(comprising three divergent mitochondrial clusters).Late Pleistocene demographic expansion of T.squamosa,during the Last Interglacial period,could have contributed to forging spatial distribution of the so far delineated genetic entities across the Indo-Western Pacific.Overall,being resilient to major climate shifts during the Pleistocene through adaptation and consequent diversification,T.squamosa could be used as a model species to track the impact of climate change on genetic variability and structure of marine species.In particular,the new information,provided in this investigation,may help with understanding and/or predicting the consequences of ongoing global warming on genetic polymorphism of endangered coral reef species among which Tridacna sp.are listed as ecologically important. 展开更多
关键词 Mollusks Red Sea and Indo-Pacific evolutionary and biogeographic histories mitochondrial DNA Pleistocene glacial refugia interglacial dispersal and expansion
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Conservation genomic investigation of an endangered conifer,Thuja sutchuenensis,reveals low genetic diversity but also low genetic load 被引量:1
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作者 Tongzhou Tao Richard IMilne +4 位作者 Jialiang Li Heng Yang Shiyang Wang Sihan Chen Kangshan Mao 《Plant Diversity》 SCIE CAS CSCD 2024年第1期78-90,共13页
Endangered species generally have small populations with low genetic diversity and a high genetic load.Thuja sutchuenensis is an endangered conifer endemic to southwestern China.It was once considered extinct in the w... Endangered species generally have small populations with low genetic diversity and a high genetic load.Thuja sutchuenensis is an endangered conifer endemic to southwestern China.It was once considered extinct in the wild,but in 1999 was rediscovered.However,little is known about its genetic load.We collected 67 individuals from five wild,isolated T.sutchuenensis populations,and used 636,151 SNPs to analyze the level of genetic diversity and genetic load in T.sutchuenensis to delineate the conservation units of T.sutchuenensis,based on whole transcriptome sequencing data,as well as target capture sequencing data.We found that populations of T.sutchuenensis could be divided into three groups.These groups had low levels genetic diversity and were moderately genetically differentiated.Our findings also indicate that T.sutchuenensis suffered two severe bottlenecks around the Last Glaciation Period and Last Glacial Maximum.Among Thuja species,T.sutchuenensis presented the lowest genetic load and hence might have purged deleterious mutations efficiently through purifying selection.However,distribution of fitness effects analysis indicated a high extinction risk for T.sutchuenensis.Multiple lines of evidence identified three management units for T.sutchuenensis.Although T.sutchuenensis possesses a low genetic load,low genetic diversity,suboptimal fitness,and anthropogenic pressures all present an extinction risk for this rare conifer.This might also hold true for many endangered plant species in the mountains all over the world. 展开更多
关键词 Sichuan Arborvitae Genetic load Deleterious mutations Demographic history Conservation genomics
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A new method to reconstruct hydrocarbon-generating histories of source rocks in a petroleum-bearing basin——the method of geological and geochemical sections 被引量:6
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作者 XIAO Xianming LIU Zufa +2 位作者 LIU Dehan SHEN Jiagui FU Jiamo 《Chinese Science Bulletin》 SCIE EI CAS 2000年第S1期35-40,共6页
Via investigating typical Palaeozoic and Mesozoic petroleum-bearing basins in China by using thermal maturation theories of organic matter to improve the conventional Karweil’s method, a new method to reconstruct hyd... Via investigating typical Palaeozoic and Mesozoic petroleum-bearing basins in China by using thermal maturation theories of organic matter to improve the conventional Karweil’s method, a new method to reconstruct hydrocarbon-generating histories of source rocks has been suggested. This method, combining geological background with geochemical information makes the calculated VRo closer to the measured one. Moreover, it enables us to make clear the hydrocarbon generation trend of source rocks during geological history. The method has the merits of simple calculation and objective presentation, especially suitable to basins whose sedimentation and tectonic movements are complicated. 展开更多
关键词 petroleum-bearing BASIN hydrocarbon-generating histories organic maturation.
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Alanine aminotransferase predicts incident steatotic liver disease of metabolic etiology: Long life to the old biomarker! 被引量:1
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作者 Amedeo Lonardo 《World Journal of Gastroenterology》 SCIE CAS 2024年第24期3016-3021,共6页
Alanine aminotransferase(ALT)serum levels increase because of hepatocellular damage.Metabolic dysfunction-associated fatty liver disease(MAFLD),which identifies steatotic liver disease(SLD)associated with≥2 metabolic... Alanine aminotransferase(ALT)serum levels increase because of hepatocellular damage.Metabolic dysfunction-associated fatty liver disease(MAFLD),which identifies steatotic liver disease(SLD)associated with≥2 metabolic abnormalities,has prominent sexual differences.The Metabolic Syndrome defines a cluster comprising abdominal obesity,altered glucose metabolism,dyslipidemia,and hypertension.Male sex,body mass index,glucose,lipids,ferritin,hypertension,and age independently predict ALT levels among blood donors.Over the last few decades,the reference range of ALT levels has been animatedly debated owing to attempts to update sex-specific reference ranges.With this backset,Chen et al have recently published a study which has two main findings.First,>80%of indi-viduals with MAFLD had normal ALT levels.Second,there was a linear increa-sing trend in the association between cumulative excess high-normal ALT levels and the rate of incident MAFLD.This study has biologically credible findings.However,it inaccurately considered sex differences in the MAFLD arena.Therefore,future studies on SLD owing to metabolic dysfunction should adopt locally determined and prospectively validated reference ranges of ALT and carefully consider sex differences in liver enzymes and MAFLD pathobiology. 展开更多
关键词 Alanine aminotransferase BIOMARKER History of medicine Metabolic dysfunction-associated fatty liver disease METABOLISM Nonalcoholic fatty liver disease Reference range Sex differences Steatotic liver disease
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Correlation of personality with individual reproductive success in shrub-nesting birds depends on their life history style
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作者 Jianchuan Li Wen Zhang +5 位作者 Ningning Sun Yujie Wang Lifang Gao Ran Feng Liqing Fan Bo Du 《Avian Research》 SCIE CSCD 2024年第1期42-49,共8页
Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain ... Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain unresolved.We addressed these two questions in three shrub-nesting birds,the Azure-winged Magpie(Cyanopica cyanus,AM),White-collared Blackbird(Turdus albocinctus,WB),and Brown-cheeked Laughingthrush(Trochalopteron henrici,BL).The personality type of an individual was first identified according to its response to a territorial intruder.Then,we compared the fleeing distance,breeding parameters,and differential expressed genes(DEGs) in the brain transcriptome between bold and shy breeders.In the three species,bold breeders exhibited more aggressiveness towards an intruder of their territory than did shy breeders.The reproductive success of bold breeders was significantly higher than that of shy breeders in AM but not in WB and BL.The three species shared one DEG,crabp1,which was up-regulated in bold relative to in shy individuals.By regulating the expression of corticotropin-releasing hormone,higher crabp1 gene expression can decrease cellular response to retinoic acid.Therefore,bold individuals are insensitive to external stresses and able to exhibit more aggressiveness to intruders than their shier counterparts.Aggressiveness is beneficial to bold individuals in AM but not in WB and BL because the former could evoke neighbors to make the same response of defending against intruders but the latter could not.Although a personality trait may have the same genetic basis across species,its correlation with reproductive success depends largely on the life history style of a species. 展开更多
关键词 BOLDNESS Life history style PERSONALITY Reproductive success Transcriptome analysis
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Across two phylogeographic breaks: Quaternary evolutionary history of a mountain aspen (Populus rotundifolia) in the Hengduan Mountains
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作者 Jieshi Tang Xiaoyan Fan +6 位作者 Richard I.Milne Heng Yang Wenjing Tao Xinran Zhang Mengyun Guo Jialiang Li Kangshan Mao 《Plant Diversity》 SCIE CAS CSCD 2024年第3期321-332,共12页
Biogeographical barriers to gene flow are central to plant phylogeography.In East Asia,plant distribution is greatly influenced by two phylogeographic breaks,the Mekong-Salween Divide and Tanaka-Kaiyong Line,however,f... Biogeographical barriers to gene flow are central to plant phylogeography.In East Asia,plant distribution is greatly influenced by two phylogeographic breaks,the Mekong-Salween Divide and Tanaka-Kaiyong Line,however,few studies have investigated how these barriers affect the genetic diversity of species that are distributed across both.Here we used 14 microsatellite loci and four chloroplast DNA fragments to examine genetic diversity and distribution patterns of 49 populations of Populus rotundifolia,a species that spans both the Mekong-Salween Divide and the Tanaka-Kaiyong Line in southwestern China.Demographic and migration hypotheses were tested using coalescent-based approaches.Limited historical gene flow was observed between the western and eastern groups of P.rotundifolia,but substantial flow occurred across both the Mekong-Salween Divide and Tanaka-Kaiyong Line,manifesting in clear admixture and high genetic diversity in the central group.Wind-borne pollen and seeds may have facilitated the dispersal of P.rotundifolia following prevalent northwest winds in the spring.We also found that the Hengduan Mountains,where multiple genetic barriers were detected,acted on the whole as a barrier between the western and eastern groups of P.rotundifolia.Ecological niche modeling suggested that P.rotundifolia has undergone range expansion since the last glacial maximum,and demographic reconstruction indicated an earlier population expansion around 600 Ka.The phylogeographic pattern of P.rotundifolia reflects the interplay of biological traits,wind patterns,barriers,niche differentiation,and Quaternary climate history.This study emphasizes the need for multiple lines of evidence in understanding the Quaternary evolution of plants in topographically complex areas. 展开更多
关键词 Chloroplast DNA MICROSATELLITE Phylogeographic break Populus rotundifolia Quaternary history Wind direction
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Genomic divergence and mutation load in the Begonia masoniana complex from limestone karsts
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作者 Yiqing Chen Lina Dong +2 位作者 Huiqin Yi Catherine Kidner Ming Kang 《Plant Diversity》 SCIE CAS CSCD 2024年第5期575-584,共10页
Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience.Howe... Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience.However,these effects are rarely studied in limestone karst plants.Here,we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex(B.liuyanii,B.longgangensis,B.masoniana and B.variegata)and investigated genomic divergence and genetic load for these four species.Our analyses revealed four distinct clusters corresponding to each species within the complex.Notably,there was only limited admixture between B.liuyanii and B.longgangensis occurring in overlapping geographic regions.All species experienced historical bottlenecks during the Pleistocene,which were likely caused by glacial climate fluctuations.We detected an asymmetric historical gene flow between group pairs within this timeframe,highlighting a distinctive pattern of interspecific divergence attributable to karst geographic isolation.We found that isolated populations of B.masoniana have limited gene flow,the smallest recent population size,the highest inbreeding coefficients,and the greatest accumulation of recessive deleterious mutations.These findings underscore the urgency to prioritize conservation efforts for these isolated population.This study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level,shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of inbreeding.Moreover,our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants. 展开更多
关键词 Conservation genomics Karst landscape Demographic history INBREEDING Isolated populations Mutation load
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Discovery and characterization of a new hydrothermal field at 2°N on the slow-spreading Carlsberg Ridge
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作者 Zhongyan QIU Yejian WANG +6 位作者 Xiqiu HAN Honglin LI Xing YU Ruyong CUI Mou LI Xuegang CHEN Jiqiang LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1106-1118,共13页
A new hydrothermal field(Tianshi)was discovered on the rift valley wall through plume anomaly surveys and geological work conducted in 2012 and 2018 between 2°35′N and 2°43′N of the slow-spreading Carlsber... A new hydrothermal field(Tianshi)was discovered on the rift valley wall through plume anomaly surveys and geological work conducted in 2012 and 2018 between 2°35′N and 2°43′N of the slow-spreading Carlsberg Ridge(CR).Here,the results of two expeditions conducted to detect and characterize the new hydrothermal field are reported.Mineralogical and geochemical data,as well as 14 C ages of a sediment core collected near the field are presented to reveal the hydrothermal history.Results show that the Tianshi field is a basalt-hosted hydrothermal system.Geochemical data of the sediments collected near the field indicate a strong hydrothermal contribution,and hydrothermal Fe and Cu fluxes range from 30 to 155 mg/(cm^(2)·ka)and 0.59 to 11.49 mg/(cm^(2)·ka),respectively.Temporal variations in the fluxes of hydrothermal Fe indicate that there have been at least three amplified hydrothermal venting events(H 1,H 2,and H 3)in the Tianshi field over the last 35.2 ka,in 28.6-35.2 ka BP,22.0-27.6 ka BP,and 1.2-11.4 ka BP,respectively.Hydrothermal event H 2 was driven by an increased magmatic production associated with sea level fall during the Last Glacial Maximum,while event H 3 was promoted by tectonic activity associated with a rapid sea level rise.This study further verified the role of sea level change in modulating hydrothermal activity on mid-ocean ridges. 展开更多
关键词 plume anomaly sediment core new hydrothermal field hydrothermal history Carlsberg Ridge
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Physico-chemical properties and macrofauna of soils under various farming systems of cold arid region in Balochistan,Pakistan
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作者 KHAN Mehmood GUL Shamim +5 位作者 KAKAR Hidayatullah PANEZAI Sanaullah KHAN Nayab ZIAD Tariq NASEEM Mahrukh SHAHEEN Umbreen 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2618-2630,共13页
Barshore is a small village in the Pishin District,Balochistan,Pakistan,with dry summers and cold rainy winters.This is an agrarian region,mostly with orchards of various fruit trees.This study investigated the physic... Barshore is a small village in the Pishin District,Balochistan,Pakistan,with dry summers and cold rainy winters.This is an agrarian region,mostly with orchards of various fruit trees.This study investigated the physico-chemical properties and macrofauna of soils under various agricultural management practices of this region.The concentrations of soil organic matter(SOM),soil organic carbon(SOC),nutrients,pH,electrical conductivity,soil texture,and the abundance and number of species of soil macrofauna of the agricultural fields were measured.Fifteen agricultural fields were sampled.Fourteen fields were orchards of apple,apricot or the mixture of apple and apricot trees and one field was a cropland,cultivated with wheat as a monocrop.The orchards were under conservation agricultural practices;whereas,the cropland was under conventional management.These agricultural lands were 2-26 years old.The concentration of soil organic matter(SOM)in the upper 0-10 cm depth of these field sites ranged from 11.6 g kg^(-1)to 32.8 g kg^(-1)soil.As compared to cropland,orchards had significantly higher concentration of SOM and SOC.A total of 18 soil macrofauna species were found and the most common and abundant were ants(Monomorium minimum,Camponotus pennsylvanicus,Solenopsis invicta,and Lasius niger)followed by Arion ssp.(Brown Slug)and earthworm Lumbricus terrestris.Regression analysis revealed non-significant relationship of the age and the concentration of SOM with the number of macrofauna species and with the concentrations of total mineral nitrogen,bioavailable phosphorus and clay.The existence of ants had no relationship with the concentration of SOM;whereas,existence of Lumbricus terrestris tended to had a positive relationship with the concentration of SOM.The field of tree-based intercropping system was 2 years of age since the land was converted from rangeland to a cropland,had two ant species coexisting.This indicates the positive influence of crop diversification on soil macrofauna. 展开更多
关键词 Soil organic matter MACROFAUNA Land use history Tree-based intercropping Conservation agriculture
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