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Development and Quality Improvement of Lianqingshan Scenic Spot in Tengzhou City
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作者 ZHANG Dongmei WANG Yifan 《Journal of Landscape Research》 2024年第1期91-95,共5页
Since the 21st century,China’s overall national strength has increased continuously.With the rapid development of the tourism industry,people have an increasingly strong demand for travel.Firstly,tourists’satisfacti... Since the 21st century,China’s overall national strength has increased continuously.With the rapid development of the tourism industry,people have an increasingly strong demand for travel.Firstly,tourists’satisfaction to Lianqingshan Scenic Spot was surveyed,and then the types of tourism resources,current development situation and problems in the scenic spot were analyzed.Finally,some countermeasures and suggestions for its development and quality improvement were put forward.It is found that based on the environmental quality,safety and service quality of Lianqingshan Scenic Spot,the basic situation of the development of the scenic spot was investigated,and the comprehensive satisfaction of each item is 3.30,3.24 and 3.32.The tourists of the scenic spot is mainly from Tengzhou City and its surrounding cities,and the popularity of the scenic spot is relatively low.The management personnel of the scenic spot needs to increase the tourist flow by improving its exposure.The problems of the scenic spot include low popularity,poor environmental quality,low safety of tourists,poor operating condition of catering industry and service quality of service personnel. 展开更多
关键词 Lianqingshan scenic spot PROBLEMS COUNTERMEASURES
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Investigating the tourism image of mountain scenic spots in China through the lens of tourist perception 被引量:2
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作者 LI Feng-jiao LIAO Xia +3 位作者 LIU Jia-ming JIANG Li-li WANG Meng-di LIU Jin-feng 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2298-2314,共17页
A favorable tourism image of high-quality mountain scenic spots(HQMSS)is crucial for tourism prosperity and sustainability.This paper establishes a framework for investigating the tourism image based on cognitive-emot... A favorable tourism image of high-quality mountain scenic spots(HQMSS)is crucial for tourism prosperity and sustainability.This paper establishes a framework for investigating the tourism image based on cognitive-emotion theory and uses natural language processing(NLP)tools to clarify the cognition,emotion,and overall tourist image of the HQMSS in China from the perspective of tourist perception.This paper examines the multi-dimensional spatial differentiation of China's overall image,including province,scenic spot scales,as well as the spatial pattern of the overall comprehensive tourism image.Strategies for comprehensively improving HQMSS's tourism image are also formulated.The results show that:(1)The cognitive image of Chinese HQMSS is categorized into core and marginal images,and the core images such as scenery and cable car are the expression of the uniqueness of mountainous scenic spots.Additionally,the cognitive image is classified into six dimensions:tourism environment,tourism supporting facilities,tourism experience,tourism price,tourism service,and tourism safety.(2)Positive emotions are the dominant mood type of HQMSS in China,followed by neutral emotions,with negative emotions being the least frequent.Emotional images vary across dimensions,with tourism environment and tourism experience evoking relatively higher emotion.(3)The spatial pattern of HQMSS for each dimension at the national,provincial,and scenic scales is diversifying.This article provides a multidimensional perspective for investigating the tourism image of mountainous scenic spots,proposes targeted recommendations to improve the overall image of HQMSS in China,and can greatly contribute to the sustainable development of mountain tourism. 展开更多
关键词 Mountain scenic spot Tourism image Spatial differentiation Natural language processing Cognitive-emotion theory Tourist perception
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Research on New Media Marketing Strategy of Quzhou Jianglang Mountain Scenic Spot Based on 4R Marketing Theory
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作者 XU Rui-xia YUAN Zhi-qian 《Sino-US English Teaching》 2023年第8期326-333,共8页
With the increasing popularity of new media,new media marketing plays an increasingly important role in the marketing of tourism scenic spots,bringing a new marketing opportunity to tourism scenic spots.Based on the 4... With the increasing popularity of new media,new media marketing plays an increasingly important role in the marketing of tourism scenic spots,bringing a new marketing opportunity to tourism scenic spots.Based on the 4R theory in marketing theory,this paper takes Quzhou Jianglang Mountain as the research object and finds that the following problems exist in the new media marketing of Quzhou Jianglang Mountain:1.The new media users are not closely enough connected;2.the response to the new media market changes is not fast enough;3.the new media marketing relationship interaction is not timely enough;and 4.the return of new media marketing is not ideal.The new media marketing strategy of Quzhou Jianglang Mountain Scenic Spot is proposed from four perspectives:association,reaction,relationship,and return.Finally,the research on the new media marketing strategy of Quzhou Jianglang Mountain Scenic Spot based on the 4R theory is summarized. 展开更多
关键词 4R theory Quzhou Jianglang Mountain scenic spot new media marketing
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Research Progress and Prospect of Tourism Carbon Emissions and Its Uncertainty Analysis Under the Goal of Low-Carbon Scenic Spots
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作者 Aihong Wang Qiguang Lyu 《Proceedings of Business and Economic Studies》 2023年第2期25-32,共8页
Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of ... Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of China’s national economy,and scenic spots are the main sites of tourism activities.Research on carbon emissions in scenic spots is of great significance for the construction of low-carbon scenic spots and the realization of the dual carbon goal.In this paper,the research on carbon emissions in tourism is reviewed,the current research progress is discussed,and further prospects are made.The research on tourism carbon emissions in China has a good foundation and achieved certain results.However,there are few studies on micro-scales such as scenic spots.The statistical data caliber and measurement methods of carbon emissions are not uniform,and there is a general lack of uncertainty analysis.Future research should focus on building a multi-spatial dimension research system,unifying the statistical caliber and measurement methods of carbon emission data,increasing uncertainty analysis,and ensuring the robustness of research results. 展开更多
关键词 Low-carbon scenic spot Carbon emissions Uncertainty analysis
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Effects of spot size on the operation mode of Ga As photoconductive semiconductor switch employing extrinsic photoconductivity 被引量:1
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作者 韦金红 李嵩 +5 位作者 陈红 曾凡正 贾成林 付泽斌 葛行军 钱宝良 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期91-99,共9页
To guide the illuminating design to improve the on-state performances of gallium arsenide(GaAs)photoconductive semiconductor switch(PCSS),the effect of spot size on the operation mode of GaAsPCSS based on a semi-insul... To guide the illuminating design to improve the on-state performances of gallium arsenide(GaAs)photoconductive semiconductor switch(PCSS),the effect of spot size on the operation mode of GaAsPCSS based on a semi-insulating wafer with a thickness of 1 mm,triggered by a 1064-nm extrinsic laser beam with the rectangular spot,has been investigated experimentally.It is found that the variation of the spot size in length and width can act on the different parts of the output waveform integrating the characteristics of the linear and nonlinear modes,and then significantly boosts the PCSS toward different operation modes.On this basis,a two-channel model containing the active and passive parts is introduced to interpret the relevant influencing mechanisms.Results indicate that the increased spot length can peak the amplitude of static domains in the active part to enhance the development of the nonlinear switching,while the extended spot width can change the distribution of photogenerated carriers on both parts to facilitate the linear switching and weaken the nonlinear switching,which have been proved by comparing the domain evolutions under different spot sizes. 展开更多
关键词 GaAs PCSS operation mode spot size on-state performances two-channel model domain evolution
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6-48月龄婴幼儿Spot屈光度异常结果分析
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作者 张永强 艾咏归 +2 位作者 刘晓慧 杨孝颖 何娇 《国际眼科杂志》 CAS 2024年第7期1162-1164,共3页
目的:分析6-48月龄婴幼儿Spot屈光异常情况,为婴幼儿屈光不正矫正及弱视早期防治提供依据。方法:对6-48月龄婴幼儿使用Spot双目视力筛查仪进行自然状况下验光,根据Spot屈光筛查仪4岁以下儿童转诊标准,收集屈光异常婴幼儿临床资料;使用... 目的:分析6-48月龄婴幼儿Spot屈光异常情况,为婴幼儿屈光不正矫正及弱视早期防治提供依据。方法:对6-48月龄婴幼儿使用Spot双目视力筛查仪进行自然状况下验光,根据Spot屈光筛查仪4岁以下儿童转诊标准,收集屈光异常婴幼儿临床资料;使用睫状肌麻痹剂视网膜检影验光,并对验光结果进行统计分析。结果:根据转诊标准共收集Spot屈光度异常婴幼儿168例336眼。其中远视及散光异常占比高,分别为38.4%和28.6%,而近视占比低(12.2%)。168例Spot屈光度异常婴幼儿中,屈光参差(≥1.00 D)共90例,其中散光性屈光参差41例(45.6%)、远视性屈光参差33例(36.7%),近视性屈光参差16例(17.8%)占比最少。共109例Spot屈光度异常婴幼儿完成睫状肌麻痹剂视网膜检影验光。对其Spot屈光度与睫状肌麻痹后检影验光结果差异及相关性分析结果显示,两者散光度差异为0.34±0.64 D(P<0.001),远视度差异为-2.10±1.27 D(P<0.001),近视度差异为-0.43±0.91 D(P=0.023);虽然二者结果存在统计学差异,但二者散光度、远视度及近视度均呈正相关(r=0.694、0.762、0.909)。结论:6-48月龄婴幼儿Spot屈光异常主要以散光、远视异常和屈光参差为主,近视异常较少;对Spot筛查异常者应进一步睫状肌麻痹剂视网膜检影验光,给予配镜矫正,有效防止婴幼儿屈光性弱视。 展开更多
关键词 spot视力筛查 婴幼儿 屈光
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T-SPOT联合颗粒酶B阳性Ts淋巴细胞对成人结核病诊断的价值
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作者 戴乾滨 陈桉军 +3 位作者 朱清 魏丹丹 刘蓬 刘洋 《标记免疫分析与临床》 CAS 2024年第8期1454-1458,1534,共6页
目的探讨结核感染T细胞斑点试验(T-SPOT.TB)联合颗粒酶B(GrB)+CD8^(+)T淋巴细胞在诊断结核病中的价值。方法选取南昌大学第一附属医院2021年2月至2022年3月疑似结核病患者212例,所有患者均保留T-SPOT结果,流式细胞仪检测外周血中T淋巴... 目的探讨结核感染T细胞斑点试验(T-SPOT.TB)联合颗粒酶B(GrB)+CD8^(+)T淋巴细胞在诊断结核病中的价值。方法选取南昌大学第一附属医院2021年2月至2022年3月疑似结核病患者212例,所有患者均保留T-SPOT结果,流式细胞仪检测外周血中T淋巴细胞亚群及其穿孔素和GrB的表达,根据出院最终诊断分为结核病组和非结核病组,比较两组间T-SPOT斑点数和淋巴细胞亚群及其穿孔素和GrB表达差异,ROC曲线分析ESAT-6斑点数,CFP-10斑点数,结核特异性抗原(TBAg)与植物血凝素(PHA)斑点数的比值(TBAg/PHA)(ESAT-6/PHA和CFP-10/PHA中较大的一个),GrB^(+)Ts(CD8^(+)T)及“结核比值”[TBAg/(PHA*GrB^(+)Ts)]的诊断效能。结果GrB^(+)Ts细胞百分比在结核组中显著高于非结核组(44.95±2.98 vs 33.49±1.87,P<0.05),而总T细胞、穿孔素+T细胞,GrB^(+)T细胞,Ts细胞和穿孔素+Ts细胞百分比差异无统计学意义(P>0.05);非结核组T-SPOT.TB阳性率为51.85%,明显低于结核组的92%,且结核组的A抗原斑点数及B抗原斑点数显著大于非结核组(P<0.05),ROC曲线显示A抗原诊断结核病的灵敏度和特异性分别为80.0%和56.8%,曲线下面积(AUC)为0.748,约登指数为0.368;B抗原的灵敏度和特异性为分别62.0%和77.8%,AUC为0.758,约登指数为0.398;A抗原+B抗原灵敏度和特异性为72.0%和74.1%,AUC为0.796,约登指数为0.461;结核组的TBAg/PHA比率要显著高于非结核组(1.21±0.17 vs 0.26±0.02,P<0.001)以0.59为cut-off值时,诊断结核病的灵敏度和特异性分别为66%和91.4%,AUC高达0.852,约登指数为0.574;结核组的“结核比值”要显著高于非结核组(4.58±0.87 vs 1.71±0.24,P<0.01),以1.24为cut-off值时,诊断结核病的灵敏度和特异性分别为82.0%和72.2%,AUC为0.794,约登指数为0.542。结论应用TBAg/PHA比率和TBAg/(PHA*GrB^(+)Ts)比值诊断结核病的效能要优于常规的T-SPOT检测,两者结合使用对结核病诊断可能具有重要价值。 展开更多
关键词 结核 T-spot TBAg/PHA比率 TBAg/(PHA*Ts颗粒酶B)比值
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Effects of Poria cocos polysaccharide on growth performance,physiological parameters,and lipid metabolism of spotted sea bass Lateolabrax maculatus
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作者 Jing LU Zhangfan HUANG +2 位作者 Youling YE Anle XU Zhongbao LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期316-331,共16页
The aquaculture industry has developed significantly over the past few decades and has had a substantial impact on the global food supply and marine fisheries resources.However,some problems arise behind the scenes du... The aquaculture industry has developed significantly over the past few decades and has had a substantial impact on the global food supply and marine fisheries resources.However,some problems arise behind the scenes due to excessive intensive farming,such as slow animal growth,frequent disease,and lipid metabolism disorders.These problems have limited the sustainable development of the aquaculture industry,and a continuable solution is required.The use of fungal polysaccharide appears to provide a solution to these problems.Therefore,different supplemented levels of Poria cocos polysaccharide(PCP)(0,0.4,0.8,1.2,1.6,and 2.0 g/kg,respectively)were fed to spotted sea bass(Lateolabrax maculatus)in similar size(30.28±0.18 g)in current study.The effects of PCP on growth,physiological parameters,and lipid metabolism of spotted sea bass were investigated after a 4-week rearing period.Results showed,fish with PCP intake presented a significantly higher weight gain,specific growth rate,and a significantly lower feed conversion ratio.Significantly higher trypsin activity in liver and intestine were observed in fish with PCP intake.The superoxide dismutase activity in serum and liver of fish with PCP intake were significantly improved,while significantly higher serum total antioxidant capacity and hepatic catalase activity were also observed.However,no significant differences in lysozyme and alkaline phosphatase activity were evident among groups.Fish with PCP intake showed a significantly lower total cholesterol,but no noteworthy change in triglyceride and lipid-metabolismrelated genes expression were observed among groups.Results indicated that intake of PCP has a positive effect on growth and antioxidant capacity of spotted sea bass,but seems to have a limited effect on the non-specific immunity and lipid metabolism of spotted sea bass.Based on the regression analysis results,1.4 g/kg of PCP is the optimal dose for spotted sea bass in size(30.28±0.18 g). 展开更多
关键词 spotted sea bass Poria cocos POLYSACCHARIDE GROWTH lipid metabolism
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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin
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作者 Xu Zeng Tao Yang +5 位作者 Jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期791-805,共15页
Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra... Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated. 展开更多
关键词 FRACTURES Development characteristics Controlling factors Shale oil Sweet spot
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Variations of phyllosphere microorganisms in asymptomatic and tobacco brown spot leaves before and after spraying 12% difenoconazole + fluxapyroxad SC
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作者 LI Tong WANG Hancheng +6 位作者 YE Guo WANG Qing NGANGUEM NZALLE Yranney Brice WANG Feng CAI Liuti FENG Ruichao ZHANG Songbai 《农药学学报》 CAS CSCD 北大核心 2024年第5期932-948,共17页
12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight... 12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology. 展开更多
关键词 tobacco brown spot DIFENOCONAZOLE fluxapyroxad microorganism communities diversity high-throughput sequencing
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Evaluation of Resistance of Different Kiwifruit Varieties (Lines) to Canker Disease and Brown Spot Disease
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作者 Wenwen Su Chongpei Zheng +5 位作者 Zhencheng Han Chunguang Ren Di Wu Tao Li Yi Yang Weijie Li 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第6期1249-1261,共13页
Kiwifruit canker and brown spot are significant diseases affecting kiwis,caused by Pseudomonas syringae patho-genic variations(Pseudomonas syringae pv.Actinidiae(Psa))and Corynesporapolytica(Corynespora cassiicola).At ... Kiwifruit canker and brown spot are significant diseases affecting kiwis,caused by Pseudomonas syringae patho-genic variations(Pseudomonas syringae pv.Actinidiae(Psa))and Corynesporapolytica(Corynespora cassiicola).At present,the research on canker disease and brown spot disease mainly focuses on the isolation and identification of pathogenic bacteria,drug control,resistance gene mining and functional verification.Practice has proved that breeding disease resistant varieties are an effective method to control canker disease and brown spot disease.However,most existing cultivars lack genes for canker and brown spot resistance.Wild kiwifruit resources in nat-ure exhibit extensive genetic diversity due to prolonged natural selection,containing numerous resistance genes.But,due to insufficient understanding of the resistance of most kiwifruit varieties(lines)to canker disease and brown spot disease,some high-quality resources have not been fully utilized.The incidence of canker and brown spot of 18 kiwifruit cultivars(lines)was measured by inoculating isolated branches and leaves,and their resistance to canker and brown spot was analyzed according to the length,disease index,mean diameter,and systematic clustering.The results were as follows:Among 18 different kiwifruit varieties(lines)for canker disease,there were two highly resistant materials,eight disease-resistant materials,four disease-susceptible materials,and two highly susceptible materials.Moreover,regarding brown spot disease,there were one highly resistant material,five dis-ease-resistant materials,four susceptible materials,and three highly susceptible materials.Furthermore,four resources were resistant to both diseases.The outcomes provided a theoretical basis for breeding kiwifruit against canker and brown spot. 展开更多
关键词 KIWIFRUIT canker disease brown spot resistance evaluation
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Detour for the inexperienced? Migration count data suggest mostly juvenile Greater Spotted Eagles appear in coastal peninsulas in China
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作者 Xu Shi Xiaoping Wang +2 位作者 Qian Wei Qiwei Lin Lei Zhu 《Avian Research》 SCIE CSCD 2024年第2期249-254,共6页
Soaring bird migration often relies on suitable terrain and airflow;therefore,route selection is vital for successful migration.While age and experience have been identified as key factor influencing migration route s... Soaring bird migration often relies on suitable terrain and airflow;therefore,route selection is vital for successful migration.While age and experience have been identified as key factor influencing migration route selection among soaring raptors in the African-Eurasian Flyway,how they shape the migration route of soaring raptors in East Asia is still largely unknown.In this study,we investigated potential variations in the routes and timing in autumn migration of juvenile and older soaring birds,using count data of Greater Spotted Eagles(Clanga clanga)from two coastal sites and two inland sites in China.From 2020 to 2023,we recorded a total of 340 individuals,with the highest site averaging over 90 individuals per autumn,making it one of the world’s top single-season counts and thus a globally important site for this species.We found that 82% and 61% records from coastal sites were juveniles,significantly higher than inland sites(15% and 24%).Juveniles at all four sites exhibited markedly earlier median passage time than non-juveniles,with brief overlapping in their main migration periods.Both coastal sites are located on the tip of peninsulas stretching southwest,requiring long overwater flights if crossing the Bohai Bay or Beibu Gulf,which would be energetically demanding and increase mortality risk.Experienced individuals may have learned to avoid such terrain and subsequent detour,while juveniles are more prone to enter these peninsulas due to lack of experience and opportunities for social learning,or following other raptor species that are more capable of powered flight.Our findings highlight the importance of age and experience in migration route selection of large soaring birds. 展开更多
关键词 Clanga clanga East Asia Greater spotted Eagle JUVENILE Migration route Social learning
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Key geological factors governing sweet spots in the Wufeng-Longmaxi shales of the Sichuan Basin,China
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作者 Zongquan Hu Zengqin Liu +4 位作者 Wei Du Zhenrui Bai Ruyue Wang Chuanxiang Sun Dongjun Feng 《Energy Geoscience》 EI 2024年第3期163-174,共12页
Production performance of the Wufeng-Longmaxi shales varies significantly among Fuling,Weirong,and Wulong fields in the Sichuan Basin.Total organic carbon(TOC)content,mineralogy,and organic matter(OM)pore characterist... Production performance of the Wufeng-Longmaxi shales varies significantly among Fuling,Weirong,and Wulong fields in the Sichuan Basin.Total organic carbon(TOC)content,mineralogy,and organic matter(OM)pore characteristics are investigated to identify key factors governing sweet spots.Siliceous shales with good preservation conditions in the Fuling Field exhibit large thickness,high TOC content and thin-section porosity(TSP),and well-developed OM macropores,thus high initial production and estimated ultimate recovery(EUR).Thin carbonate-containing siliceous shales with good preservation conditions in the Weirong Field feature medium-to-high TOC and well-developed OM macropores but low TSP,leading to high initial production but low EUR.Siliceous shales with poor preservation conditions in the Wulong Field are characterized by large thickness,high TOC,low TSP and poorly-developed OM macropores,causing low initial production and EUR.Both sedimentary and preservation conditions are intrinsic decisive factors of sweet spots,as they control the mineral composition,TOC,and OM macropore development.Deep-water shales in transgressive systems tracts(TSTs)exhibit better-developed OM macropores and greater TOC compared to highstand systems tracts(HSTs).OM macropores are most prevalent in siliceous shales,followed by carbonate-containing siliceous shales and then argillaceous shales.Furthermore,good preservation conditions are conducive to retain OM macropores with low pore aspect ratio(PAR).Comparison among the three fields shows that high-TOC silicious shales with good preservation conditions are the highest in TSP and EUR.Therefore,organic richness,lithofacies,and preservation conditions are the major factors which determine OM pore development,governing the sweet spots of the Wufeng-Longmaxi shales. 展开更多
关键词 Shale gas Organic matter pores Sweet spot Wufeng-Longmaxi shales Sichuan basin
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ToF-SIMS characterization of a bare-spot defect in a hot-dip galvanized boron-added steel sheet
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作者 JIN Xinyan HONG Jufeng 《Baosteel Technical Research》 CAS 2024年第3期1-9,共9页
To determine the root cause of a bare-spot defect in a hot-dip galvanized boron-added steel sheet,we performed metallurgical characterizations using time-of-flight secondary ion mass spectrometry(ToF-SIMS)in addition ... To determine the root cause of a bare-spot defect in a hot-dip galvanized boron-added steel sheet,we performed metallurgical characterizations using time-of-flight secondary ion mass spectrometry(ToF-SIMS)in addition to glow discharge optical emission spectrometry,field-emission scanning electron microscopy(FE-SEM),and energy dispersive spectroscopy.Mn and B enrichments on the steel surface in the bare-spot area were detected through various methods.FE-SEM revealed external oxide nodules and zinc droplets,which indicated poor wettability.ToF-SIMS further revealed considerably more detailed lateral and depth distributions of Mn,B,and Al.The formation of external Mn-B compound oxides on the steel surface prior to hot dipping,which substantially deteriorated the wettability and prevented the formation of a Fe_(2)Al_(5)inhibition layer,resulted in the formation of a bare-spot defect.ToF-SIMS mapping of Al ion proved that a slight reaction still occurred between the dissolved Al in the molten zinc bath and steel substrate,although no evident Fe_(2)Al_(5)inhibition layer formed in the bare-spot area. 展开更多
关键词 bare spot selective oxidation galvanized steel ToF-SIMS
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Research status and hotspots of tight junctions and colorectal cancer:A bibliometric and visualization analysis
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作者 Hui-Min Li Yin Liu +5 位作者 Meng-Di Hao Xiao-Qing Liang Da-Jin Yuan Wen-Bin Huang Wen-Jie Li Lei Ding 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第8期3705-3715,共11页
BACKGROUND Colorectal cancer(CRC)is the third most common cancer worldwide and the second leading cause of cancer-related death.Over the past two decades,numerous researchers have provided important evidence regarding... BACKGROUND Colorectal cancer(CRC)is the third most common cancer worldwide and the second leading cause of cancer-related death.Over the past two decades,numerous researchers have provided important evidence regarding the role of tight junction(TJ)proteins in the occurrence and progression of CRC.The causal relationship between the presence of specific TJ proteins and the development of CRC has also been confirmed.Despite the large number of publications in this field,a bibliometric study to review the current state of research and highlight the research trends and hotspots in this field has not yet been performed.AIM To analyze research on TJs and CRC,summarize the field’s history and current status,and predict future research directions.METHODS We searched the Science Citation Index Expanded database for all literature on CRC and TJs from 2001-2023.We used bibliometrics to analyze the data of these papers,such as the authors,countries,institutions,and references.Co-authorship,co-citation,and co-occurrence analyses were the main methods of analysis.CiteSpace and VOSviewer were used to visualize the results.RESULTS A total of 205 studies were ultimately identified.The number of publications on this topic has steadily increased since 2007.China and the United States have made the largest contributions to this field.Anticancer Research was the most prolific journal,publishing 8 articles,while the journal Oncogene had the highest average citation rate(68.33).Professor Dhawan P was the most prolific and cited author in this field.Co-occurrence analysis of keywords revealed that“tight junction protein expression”,“colorectal cancer”,“intestinal microbiota”,and“inflammatory bowel disease”had the highest frequency of occurrence,revealing the research hotspots and trends in this field.CONCLUSION This bibliometric analysis evaluated the scope and trends of TJ proteins in CRC,providing valuable research perspectives and future directions for studying the connection between the two.It is recommended to focus on emerging research hotspots,such as the correlations among intestinal microbiota,inflammatory bowel disease,TJ protein expression,and CRC. 展开更多
关键词 Colorectal cancer Tight junctions Bibliometric analysis Research trends Hot spots
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Investigation and improvement of tiny spot defects on hot-dip galvanized automotive steel sheets
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作者 GE Zhiyong YANG Bo YANG Jiwu 《Baosteel Technical Research》 CAS 2024年第2期32-38,共7页
The causes of tiny spot defects on the surface of hot-dip galvanized automotive steel sheets were studied using scanning electron microscopy(SEM)and energy dispersive spectrometer(EDS),and effective control measures w... The causes of tiny spot defects on the surface of hot-dip galvanized automotive steel sheets were studied using scanning electron microscopy(SEM)and energy dispersive spectrometer(EDS),and effective control measures were introduced.The results show that rubbing against the top roller after galvanizing is easy due to the local thickness of tiny spot defect location coating;therefore,the surface morphology is different from the normal part.Three kinds of defects,namely zinc slag,small slivers,and pitting,are likely to cause local thickening of the coating after galvanizing,leading to the formation of tiny spots.Therefore,resolving the three types of defects can effectively control the generation of tiny spot defects.Among them,due to the hereditary nature of the small sliver defect,focusing on its control and supervision is necessary. 展开更多
关键词 hot-dip galvanizing tiny spot zinc slag PITTING small sliver
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Overexpression of auxin/indole-3-acetic acid gene MdIAA24 enhances Glomerella leaf spot resistance in apple(Malus domestica)
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作者 Qian Wang Dong Huang +2 位作者 Wenyan Tu Fengwang Ma Changhai Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期15-24,共10页
Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones,yet its role in apple disease resistance remains unclear.In this study,we investigated the function of auxin/i... Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones,yet its role in apple disease resistance remains unclear.In this study,we investigated the function of auxin/indole-3-acetic acid(IAA)gene Md IAA24 overexpression in enhancing apple resistance to Glomerella leaf spot(GLS)caused by Colletotrichum fructicola(Cf).Analysis revealed that,upon Cf infection,35S::Md IAA24 plants exhibited enhanced superoxide dismutase(SOD)and peroxidase(POD)activity,as well as a greater amount of glutathione(reduced form)and ascorbic acid accumulation,resulting in less H_(2)O_(2)and superoxide anion(O_(2)^(-))in apple leaves.Furthermore,35S::Md IAA24 plants produced more protocatechuic acid,proanthocyanidins B1,proanthocyanidins B2 and chlorogenic acid when infected with Cf.Following Cf infection,35S::Md IAA24 plants presented lower levels of IAA and jasmonic acid(JA),but higher levels of salicylic acid(SA),along with the expression of related genes.The overexpression of Md IAA24 was observed to enhance the activity of chitinase andβ-1,3-glucanase in Cfinfected leaves.The results indicated the ability of Md IAA24 to regulate the crosstalk between IAA,JA and SA,and to improve reactive oxygen species(ROS)scavenging and defense-related enzymes activity.This jointly contributed to GLS resistance in apple. 展开更多
关键词 APPLE MdIAA24 Glomerella leaf spot(GLS) Antioxidant capacity AUXIN Salicylic acid Jasmonic acid
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Analysis of spot defects on the surface of a cold-rolled Fe-36%Ni alloy strip
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作者 TIAN Yuxin WANG Yu ZHU Yincun 《Baosteel Technical Research》 CAS 2024年第2期27-31,共5页
Many spot defects were found on the surface of a cold-rolled Fe-36%Ni alloy strip produced in a factory,which seriously affected the surface quality of the product.Through metallographic microscopy and scanning electr... Many spot defects were found on the surface of a cold-rolled Fe-36%Ni alloy strip produced in a factory,which seriously affected the surface quality of the product.Through metallographic microscopy and scanning electron microscopy analyses,it was found that the spot defects were caused by the residual oxide layer on the surface of the cold-rolled Fe-36%Ni alloy strip after hydrogen annealing.By properly increasing the grinding amount of the blank before cold rolling to remove the oxide layer,the spot defects on the surface of the cold-rolled strip were effectively eliminated,and the surface quality of the product was ensured. 展开更多
关键词 Fe-36%Ni alloy cold-rolled strip spot defect
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Genomic Selection for Frogeye Leaf Spot Resistance in Soybean
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作者 Yao Lanning Chen Yizhi +4 位作者 Li Haochen Zhang Yue Xia Mingyu Ning Shicheng Ning Hailong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期11-19,共9页
Soybean frogeye leaf spot(FLS) disease is a global disease affecting soybean yield, especially in the soybean growing area of Heilongjiang Province. In order to realize genomic selection breeding for FLS resistance of... Soybean frogeye leaf spot(FLS) disease is a global disease affecting soybean yield, especially in the soybean growing area of Heilongjiang Province. In order to realize genomic selection breeding for FLS resistance of soybean, least absolute shrinkage and selection operator(LASSO) regression and stepwise regression were combined, and a genomic selection model was established for 40 002 SNP markers covering soybean genome and relative lesion area of soybean FLS. As a result, 68 molecular markers controlling soybean FLS were detected accurately, and the phenotypic contribution rate of these markers reached 82.45%. In this study, a model was established, which could be used directly to evaluate the resistance of soybean FLS and to select excellent offspring. This research method could also provide ideas and methods for other plants to breeding in disease resistance. 展开更多
关键词 LASSO regression stepwise regression genomic selection model SOYBEAN frogeye leaf spot(FLS)disease
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基于SPOT4和Landsat5 TM的不同影像融合方法质量对比研究
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作者 肖远平 唐育林 曾小威 《河南科技》 2024年第14期88-92,共5页
【目的】探究不同影像融合方法对SPOT4全色影像和Landsat5 TM多光谱影像融合效果的影响。【方法】采用13种不同的影像融合算法开展融合试验,并通过定性和定量分析的方式,对融合结果进行综合评价分析。【结果】结果表明,融合影像的信息... 【目的】探究不同影像融合方法对SPOT4全色影像和Landsat5 TM多光谱影像融合效果的影响。【方法】采用13种不同的影像融合算法开展融合试验,并通过定性和定量分析的方式,对融合结果进行综合评价分析。【结果】结果表明,融合影像的信息熵相比原影像有所增强,RGB三通道的熵值分布更为均匀,主要集中在50~200之间。此外,不同地物类型对融合方法的效果产生了显著影响。对于水体和植被,Brovey、HSV、IHS和EF方法展现出了良好的光谱保真性和细节增强能力,因此更适用于目视解译。NND法在这些区域出现了轻微的光谱失真现象,导致其分类精度偏低。【结论】针对不同传感器的影像选择适当的融合方法,对于提高遥感影像的解译精度和应用价值具有重要意义。 展开更多
关键词 影像融合 质量评价 spot4 Landsat5 TM
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