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Tree mycorrhizal associations determine how biodiversity,large trees,and environmental factors drive aboveground carbon stock in temperate forests
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作者 Yue Chen Zikun Mao +2 位作者 Jonathan A.Myers Jinghua Yu Xugao Wang 《Forest Ecosystems》 SCIE CSCD 2024年第4期448-456,共9页
Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these f... Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these factors depends on tree mycorrhizal associations,whereby large-tree effects may be driven by ectomycorrhizal(EM)trees,diversity effects may be driven by arbuscular mycorrhizal(AM)trees,and environment effects may depend on differential climate and soil preferences of AM and EM trees.To test this hypothesis,we used forest-inventory data consisting of over 80,000 trees from 631 temperate-forest plots(30 m×30 m)across Northeast China to examine how biodiversity(species diversity and ecological uniqueness),large trees(top 1%of tree diameters),and environmental factors(climate and soil nutrients)differently regulate aboveground carbon stocks of AM trees,EM trees,and AM and EM trees combined(i.e.total aboveground carbon stock).We found that large trees had a positive effect on both AM and EM tree carbon stocks.However,biodiversity and environmental factors had opposite effects on AM vs.EM tree carbon stocks.Specifically,the two components of biodiversity had positive effects on AM tree carbon stocks,but negative effects on EM tree carbon stocks.Environmental heterogeneity(mean annual temperature and soil nutrients)also exhibited contrasting effects on AM and EM tree carbon stocks.Consequently,for the total carbon stock,the positive large-tree effect far surpasses the diversity and environment effect.This is mainly because when integrating AM and EM tree carbon stock into total carbon stock,the opposite diversity-effect(also environment-effect)on AM vs.EM tree carbon stock counteracts each other while the consistent positive large-tree effect on AM and EM tree carbon stock is amplified.In summary,this study emphasized a mycorrhizal viewpoint to better understand the determinants of overarching aboveground carbon profile across regional forests. 展开更多
关键词 BIODIVERSITY Ecological uniqueness Environment heterogeneity Large trees Mycorrhizal associations Tree carbon stock
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The Impact of Short Selling Disclosure Regulatory Constraint on the Lending Market and Stock Ownership
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作者 Geoffrey Ducournau Jinliang Li +2 位作者 Yan Li Zigan Wang Qie Ellie Yin 《Journal of Modern Accounting and Auditing》 2024年第3期99-114,共16页
We examine the impact of the short sell disclosure(SSD)regime on the stock lending market and investor behaviors,employing a staggered difference-indifference(DiD)methodology.Our research reveals that the introduction... We examine the impact of the short sell disclosure(SSD)regime on the stock lending market and investor behaviors,employing a staggered difference-indifference(DiD)methodology.Our research reveals that the introduction of the disclosure regime enhances market transparency,resulting in a diminished appeal of stock ownership in the lending market for active investors.This shift is accompanied by a reduction in information leakage risks and longer loan durations.Specifically,our analysis reveals a significant decrease in the risk of loan recall by 4.87%,accompanied by an average increase of 23.72%in loan duration for short selling activities.Furthermore,the cost associated with short-sell disclosure causes a decline in both lending supply and short demand. 展开更多
关键词 short sell disclosure stock equity lending market stock ownership
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Design Strategies and Practice Paths for Improving Urban Quality in the Stock Era
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作者 Li Tianfei Zhou Xiaotian +1 位作者 Han Shengsheng Liu Yuxuan 《Journal of Landscape Research》 2024年第2期18-24,共7页
In the middle and later stages of urbanization development,the growth of the real estate industry will stagnate,and urban renewal will become the mainstream.With the advancement of urban renewal,there are still proble... In the middle and later stages of urbanization development,the growth of the real estate industry will stagnate,and urban renewal will become the mainstream.With the advancement of urban renewal,there are still problems in improving the quality of cities in the stock era and their design strategies.This paper analyzed the Linping Old City organic renewal project and the Xishui River ecological governance project in the stock era of urban quality improvement by sorting out the current development status,historical background,planning types,and design strategies of quality improvement in the stock era from the perspective of urban renewal,combining with project overview,main problems,design methods,and design content.Urban renewal is the leading direction for promoting urban development and construction on a global scale,and countries formulate different plans and practices based on their local characteristics.Urban renewal strategies should be diversified,and focus on livable environments,urban characteristics,etc.,while considering human factors,green innovation,etc.,in order to achieve smart community management and enhance the economic and social benefits brought by urban attractiveness.For successful cases such as the Linping Old City and Xishui River ecological governance project,corresponding urban quality improvement strategies and implementation plans should be formulated according to local conditions,with emphasis on social participation and people’s livelihood improvement.This study can help urban planning pay more attention to rational utilization and upgrading of existing urban resources,adapt to the current urban development situation,and promote sustainable urban development. 展开更多
关键词 stock era Organic renewal Ecological governance Linping Old City Xishui River
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China’s Monetary Policy Impacts on Money and Stock Markets
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作者 Fang Fang 《Proceedings of Business and Economic Studies》 2024年第2期46-52,共7页
This study investigated the impact of China’s monetary policy on both the money market and stock markets,assuming that non-policy variables would not respond contemporaneously to changes in policy variables.Monetary ... This study investigated the impact of China’s monetary policy on both the money market and stock markets,assuming that non-policy variables would not respond contemporaneously to changes in policy variables.Monetary policy adjustments are swiftly observed in money markets and gradually extend to the stock market.The study examined the effects of monetary policy shocks using three primary instruments:interest rate policy,reserve requirement ratio,and open market operations.Monthly data from 2007 to 2013 were analyzed using vector error correction(VEC)models.The findings suggest a likely presence of long-lasting and stable relationships among monetary policy,the money market,and stock markets.This research holds practical implications for Chinese policymakers,particularly in managing the challenges associated with fluctuation risks linked to high foreign exchange reserves,aiming to achieve autonomy in monetary policy and formulate effective monetary strategies to stimulate economic growth. 展开更多
关键词 Chinese money market Chinese stocks market Monetary policy Shanghai Interbank Offered Rate(SHIBOR) Vector error correction models
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心房颤动患者射频消融术中首剂肝素ACT预测模型构建
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作者 冯婕 鲍志鹏 +6 位作者 周丽华 赵雅凡 宋雯 周燕 陈思彤 渠强 何英 《南京医科大学学报(自然科学版)》 CAS 北大核心 2024年第12期1715-1722,共8页
目的:建立并验证心房颤动患者射频消融术中给予首剂肝素30 min后测得活化凝血时间(activated clotting time,ACT)(30 min-ACT)的列线图预测模型。方法:选择2020年1月—2022年12月于南京医科大学第一附属医院心内科导管室行导管射频消融... 目的:建立并验证心房颤动患者射频消融术中给予首剂肝素30 min后测得活化凝血时间(activated clotting time,ACT)(30 min-ACT)的列线图预测模型。方法:选择2020年1月—2022年12月于南京医科大学第一附属医院心内科导管室行导管射频消融治疗、非瓣膜性心房颤动患者1 090例,以3∶1比例随机分为训练集和测试集,对两组各项指标进行Kruskal-Wallis检验、卡方检验比较其基线特征。通过LASSO回归及单因素、多因素线性回归分析影响30 min-ACT的因素,据此建立心房颤动患者射频消融术中30 min-ACT的预测模型并评估其预测效果。结果:多因素结果分析提示卒中史、华法林、血小板计数、凝血酶原时间、基础ACT、基础ACT^(2)、首剂肝素剂量是房颤患者射频消融术中首剂肝素ACT的独立预测因素,据此构建的列线图预测模型预测具有一定的准确度(训练集65.9%,测试集74.6%)和较高的灵敏度(训练集77.4%,测试集83.0%)。结论:根据卒中史、华法林、血小板计数、凝血酶原时间、基础ACT、基础ACT^(2)、首剂肝素剂量构建的30 min-ACT列线图模型可以预测心房颤动患者射频消融术中首剂肝素的抗凝效果,对临床工作具有一定指导作用。 展开更多
关键词 心房颤动 射频消融术 肝素抗凝 首剂肝素act 预测模型
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Impact of the Three Gorges Dam on the spawning stock and natural reproduction of Chinese sturgeon in the Changjiang River,China 被引量:8
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作者 高欣 林鹏程 +2 位作者 黎明政 段中华 刘焕章 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期894-901,共8页
Chinese sturgeon(Acipenser sinensis) is the flagship species of the Changjiang River.The migration route of this species is blocked by the first dam,the Gezhou Dam,and its reproduction is affected by the Three Gorges ... Chinese sturgeon(Acipenser sinensis) is the flagship species of the Changjiang River.The migration route of this species is blocked by the first dam,the Gezhou Dam,and its reproduction is affected by the Three Gorges Dam(TGD),one of the largest dams in the world.We studied the impact of the impoundment of the Three Gorges Reservoir(TGR) since 2003 on the spawning stock and the natural reproduction of the Chinese sturgeon by using our monitoring data from 1997 to 2013.Results indicate that TGR impoundment has delayed the first spawning dates of the fish from middle-late October to late November,decreased the amount of spawning activities from twice to only once each year,and significantly reduced egg production.In particular,the fish did not demonstrate any spawning activities in 2013.Therefore,TGR impoundment significantly affects the natural reproduction of the fish downstream of the TGD.The spawning stock size of the fish is also predicted to further decrease in the future,which will lead to a risk of population extinction.Ecological regulations must be imposed on decreasing the water temperature to 20℃before mid-October and increasing water discharge downstream of the TGD in October to induce spawning of the Chinese sturgeon. 展开更多
关键词 Chinese sturgeon Three Gorges Dam spawning activity spawning stock CONSERVATION
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基于ACT反馈的延续性护理对老年间质性肺炎患者治疗依从性的影响评价
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作者 李丽 苗桂玲 《中文科技期刊数据库(文摘版)医药卫生》 2024年第10期0186-0189,共4页
分析以ACT反馈为基础的延续性护理模式,对老年间质性肺炎患者的影响价值。方法 从2022年7月开始,截至2023年7月,本院总计选入老年间质性肺炎患者60例,经抽签法进行两组均分。30例对照组实施基础护理,30例研究组实施基于ACT反馈的延续性... 分析以ACT反馈为基础的延续性护理模式,对老年间质性肺炎患者的影响价值。方法 从2022年7月开始,截至2023年7月,本院总计选入老年间质性肺炎患者60例,经抽签法进行两组均分。30例对照组实施基础护理,30例研究组实施基于ACT反馈的延续性护理。比较两组护理后肺功能水平、临床恢复结果、生活质量以及总依从率。结果 研究组各肺功能结果、生活质量评分高于对照组;恢复时间短于对照组;总依从率高于对照组,差异有统计学意义(P<0.05)。结论 老年间质性肺炎患者,进行基于ACT反馈的延续性护理,可提升生活质量和依从性,稳定肺功能水平。 展开更多
关键词 act反馈 延续性护理 老年间质性肺炎 效果分析
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Stable isotopic composition of otoliths in identification of stock structure of small yellow croaker(Larimichthys polyactis) in China 被引量:5
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作者 WANG Yukun HUANG Jiansheng +2 位作者 TANG Xuexi JIN Xianshi SUN Yao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第6期29-33,共5页
Oxygen and carbon isotope ratios(δ^(18)O and δ^(13)C) in otoliths were used to identify the stock structure of small yellow croaker,Larimichthys polyactis.Otoliths were collected from fish at five locations ac... Oxygen and carbon isotope ratios(δ^(18)O and δ^(13)C) in otoliths were used to identify the stock structure of small yellow croaker,Larimichthys polyactis.Otoliths were collected from fish at five locations across the Yellow Sea and the Bohai Sea representing most of their distributional range and fisheries areas.The significant differences in the isotopic signatures showed that the five locations could be chemically distinguished and clearly separated,indicating stock subdivision.Correlation of δ^(18)O and δ^(13)C values suggested that population of L.polyactis could be divided into the Bohai Sea group,the southern Yellow Sea group and the central Yellow Sea group.Discriminant analysis of δ^(18)O and δ^(13)C values demonstrated a high significant difference with 85.7% classification accuracy.The spatial separation of L.polyactis indicated a complex stock structure across the Yellow Sea and the Bohai Sea.These results indicate that optimal fisheries management may require a comprehensive consideration on the current spatial arrangements.This study has provided further evidence that measurement of the stable isotopes ratios in otolith can be a valuable tool in the delineation of fishery management units. 展开更多
关键词 small yellow croaker OTOLITH stable isotope chemistry stock structure
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Impacts of Land Cover Changes on Ecosystem Carbon Stocks Over the Transboundary Tumen River Basin in Northeast Asia 被引量:8
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作者 XIANG Hengxing JIA Mingming +5 位作者 WANG Zongming LI Lin MAO Dehua ZHANG Da CUI Guishan ZHU Weihong 《Chinese Geographical Science》 SCIE CSCD 2018年第6期973-985,共13页
Understanding the effects of land cover changes on ecosystem carbon stocks is essential for ecosystem management and envi- ronmental protection, particularly in the transboundary region that has undergone marked chang... Understanding the effects of land cover changes on ecosystem carbon stocks is essential for ecosystem management and envi- ronmental protection, particularly in the transboundary region that has undergone marked changes. This study aimed to examine the impacts of land cover changes on ecosystem carbon stocks in the transboundary Tureen River Basin (TTRB). We extracted the spatial information from Landsat Thematic Imager (TM) and Operational Land Imager (OLI) images for the years 1990 and 2015 and obtained convincing estimates of terrestrial biomass and soil carbon stocks with the INVEST model. The results showed that forestland, cropland and built-up land increased by 57.5, 429.7 and 128.9 km2, respectively, while grassland, wetland and barren land declined by 24.9, 548.0 and 43.0 km2, respectively in the TTRB from 1990 to 2015. The total carbon stocks encompassing aboveground, belowground, soil and litter layer carbon storage pools have declined from 831.48 Tg C in 1990 to 831.42 Tg C in 2015 due to land cover changes. In detail, the carbon stocks de- creased by 3.13 Tg C and 0.44 Tg C in Democratic People's Republic of Korea (North Korea) and Russia, respectively, while increased by 3.51 Tg C in China. Furthermore, economic development, and national policy accounted for most land cover changes in the TTRB. Our results imply that effective wetland and forestland protection policies among China, North Korea, and Russia are much needed for protecting the natural resources, promoting local ecosystem services and regional sustainable development in the transnational area. 展开更多
关键词 land cover change carbon stock INVEST model Transboundary Tumen River Basin Northeast Asia
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Impact of nutrient losses from agricultural lands on nutrient stocks in Dianshan Lake in Shanghai, China 被引量:2
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作者 Shou-bing WANG Xiao-xue MA +2 位作者 Zheng-qiu FAN Wei-qian ZHANG Xiao-yong QIAN 《Water Science and Engineering》 EI CAS CSCD 2014年第4期373-383,共11页
Abstract: The water quality of Dianshan Lake in Shanghai Municipality, China, is impacted by nutrient losses from agricultural lands around the lake. In this study, nine types of agricultural land use were monitored ... Abstract: The water quality of Dianshan Lake in Shanghai Municipality, China, is impacted by nutrient losses from agricultural lands around the lake. In this study, nine types of agricultural land use were monitored in 2010 and 2011, and a correlation analysis between nutrient losses from agricultural non-point sources (NPS) and nutrient stocks in the lake was conducted over monthly and seasonal time periods. The results indicate that the monthly average concentration of total nitrogen (TN) ranged from 1.41 to 7.34 mg/L in 2010 and from 1.52 to 5.90 mg/L in 2011, while the monthly average concentration of total phosphorous (TP) ranged from 0.11 to 0.26 mg/L in 2010 and from 0.13 to 0.30 mg/L in 2011. The annual loss of TN from agricultural NPS was 195.55 tons in 2010 and 208.40 tons in 2011. The cultivation of water oat made the largest contribution to the loss of TN. The annual loss of TP was 44.58 tons in 2010 and 48.12 tons in 2011, and multi-vegetable cultivation made the largest contribution to the loss of TP. The results of correlation analysis show that the monthly stocks of TN and TP in the lake have a positive correlation with the monthly losses of TN and TP from agricultural NPS. According to the seasonal data, the stocks of TN and TP in the lake both have a much stronger correlation with the losses of TN and TP from agricultural NPS in summer than in other seasons. Agricultural NPS pollution control should be the main focus for the water resource conservation in this area. 展开更多
关键词 agricultural non-point source pollution nutrient losses nutrient stocks totalnitrogen (TN) total phosphorus (TP) Dianshan Lake
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Permanence and global attractivity of stage-structured predator-prey model with continuous harvesting on predator and impulsive stocking on prey 被引量:1
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作者 焦建军 陈兰荪 +1 位作者 Juan J.Nieto Torres Angela 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第5期653-663,共11页
We investigate a stage-structured delayed predator-prey model with impulsive stocking on prey and continuous harvesting on predator. According to the fact of biological resource management, we improve the assumption o... We investigate a stage-structured delayed predator-prey model with impulsive stocking on prey and continuous harvesting on predator. According to the fact of biological resource management, we improve the assumption of a predator-prey model with stage structure for predator population that each individual predator has the same ability to capture prey. It is assumed that the immature and mature individuals of the predator population are divided by a fixed age, and immature predator population does not have the ability to attach prey. Sufficient conditions are obtained, which guarantee the global attractivity of predator-extinction periodic solution and the permanence of the system. Our results show that the behavior of impulsive stocking on prey plays an important role for the permanence of the system, and provide tactical basis for the biological resource management. Numerical analysis is presented to illuminate the dynamics of the system. 展开更多
关键词 stage-structured impulsive stocking continuous harvesting global attractivity PERMANENCE
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NMR studies of stock process water and reaction pathways in hydrothermal carbonization of furfural residue 被引量:1
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作者 Fen Yue Christian Marcus Pedersen +5 位作者 Xiuyin Yan Yequn Liu Danlei Xiang Caifang Ning Yingxiong Wang Yan Qiao 《Green Energy & Environment》 SCIE 2018年第2期163-171,共9页
Hydrothermal carbonization(HTC) is a valuable approach to convert furfural residue(FR) into carbon material. The prepared biochars are usually characterized comprehensively, while the stock process water still remains... Hydrothermal carbonization(HTC) is a valuable approach to convert furfural residue(FR) into carbon material. The prepared biochars are usually characterized comprehensively, while the stock process water still remains to be studied in detail. Herein, a NMR study of the main components in stock process water generated at different HTC reaction conditions was reported. Various qualitative and quantitative NMR techniques(~1H and ^(13)C NMR,~1H-~1H COSY and ~1H-^(13)C HSQC etc.) especially 1D selective gradient total correlation spectroscopy(TOCSY NMR) were strategically applied in the analysis of HTC stock process water. Without separation and purification, it was demonstrated that the main detectable compounds are 5-hydroxymethylfurfural, formic acid, methanol, acetic acid, levulinic acid, glycerol, hydroxyacetone and acetaldehyde in this complicate mixture. Furthermore, the relationship between the concentration of major products and the reaction conditions(180-240 ℃ at 8 h, and 1-24 h at 240 ℃) was established. Finally, reasonable reaction pathways for hydrothermal conversion of FR were proposed based on this result and our previously obtained characteristics of biochars. The routine and challenging NMR methods utilized here would be an alternative other than HPLC or GC for biomass conversion research and can be extended to more studies. 展开更多
关键词 NMR Hydrothermal carbonization Furfural residue stock process water
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The impact of the COVID‑19 outbreak on Chinese‑listed tourism stocks 被引量:3
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作者 Wenmin Wu Chien‑Chiang Lee +1 位作者 Wenwu Xing Shan‑Ju Ho 《Financial Innovation》 2021年第1期476-493,共18页
This research explored the effects of the coronavirus disease(COVID-19)outbreak on stock price movements of China’s tourism industry by using an event study method.The results showed that the crisis negatively impact... This research explored the effects of the coronavirus disease(COVID-19)outbreak on stock price movements of China’s tourism industry by using an event study method.The results showed that the crisis negatively impacted tourism sector stocks.Further quantile regression analyses supported the non-linear relationship between the government’s responses and stock returns.The results present that the resurgence of the virus in Beijing did bring about a short-term negative impact on the tourism industry.The empirical results can be used for future researchers to conduct a comparative study of cultural differences concerning government responses to the COVID-19. 展开更多
关键词 COVID-19 TOURISM Event study method stock market China
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Impact of rainfed and irrigated agriculture systems on soil carbon stock under different climate scenarios in the semi-arid region of Brazil 被引量:2
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作者 André L CARVALHO Renato A ARAúJO-NETO +2 位作者 Guilherme B LYRA Carlos E P CERRI Stoécio M F MAIA 《Journal of Arid Land》 SCIE CSCD 2022年第4期359-373,共15页
Understanding the dynamics of soil organic carbon(SOC) is of fundamental importance in land use and management, whether in the current researches or in future scenarios of agriculture systems considering climate chang... Understanding the dynamics of soil organic carbon(SOC) is of fundamental importance in land use and management, whether in the current researches or in future scenarios of agriculture systems considering climate change. In order to evaluate SOC stock of the three districts(Delmiro Gouveia, Pariconha, and Inhapi districts) in the semi-arid region of Brazil in rainfed and irrigated agriculture systems under different climate scenarios using the Century model, we obtained RCP4.5 and RCP8.5 climate scenarios derived from the Eta Regional Climate Model(Eta-Had GEM2-ES and Eta-MIROC5) from the National Institute for Space Research, and then input the data of bulk density, p H, soil texture, maximum temperature, minimum temperature, and rainfall into the soil and climate files of the Century model. The results of this study showed that the Eta-Had GEM2-ES model was effective in estimating air temperature in the future period. In rainfed agriculture system, SOC stock under the baseline scenario was lower than that under RCP4.5 and RCP8.5 climate scenarios, while in irrigated agriculture system, SOC stock in the almost all climate scenarios(RCP4.5 and RCP8.5) and models(Eta-Had GEM2-ES and Eta-MIROC5) will increase by 2100. The results of this study will help producers in the semi-arid region of Brazil adopt specific agriculture systems aimed at mitigating greenhouse gas emissions. 展开更多
关键词 soil carbon stock agriculture systems climate scenarios Century model semi-arid region
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Mineralogical and Petrographic Characteristics of Indium and REE-Bearing Accessory Phases in the Kymi Granite Stock, Southern Finland 被引量:1
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作者 Thair Al-Ani Timo Ahtola +1 位作者 Janne Kuusela Nadhir Al-Ansari 《Natural Resources》 2018年第2期23-41,共19页
The Wiborg rapakivi batholith (1.64 Ga) in southeastern Finland with documented occurrences of REE, indium and Zn-Cu-Pb sulphide mineralization was studied. Hydrothermal greisen and quartz vein type Fe-Sn and Zn-Cu-Pb... The Wiborg rapakivi batholith (1.64 Ga) in southeastern Finland with documented occurrences of REE, indium and Zn-Cu-Pb sulphide mineralization was studied. Hydrothermal greisen and quartz vein type Fe-Sn and Zn-Cu-Pb are found in the Kymi granite stock as intrusions. They are enriched with indium and rare earth elements, with roquesite (CuInS2) being a major indium- carrier, whereas monazite (Ce), allanite (Ce), bastn&#228;esite (Ce), xenotime-(Y) and thorite are the main REE carriers. Combination of optical and field emission scanning electron microscopy (FE-SEM) and electron probe microanalysis (EPMA) were used to study the indium and REE-bearing mineral assemblages. EPMA of roquesite found in galena had a composition of 26.16% S, 0.02% Fe, 25.06% Cu, 0.03% Zn, 1.06% As, 0.31% Sb and 47.14% In. Substitution reaction Pb2+S2-Cu+In3+S2- is the cause of the incorporation of indium in the galena structure. The majority of the LREE are carried by monazite, bastn&#228;esite and allanite, and the HREE by xenotime and zircon. There is a partial solid solution between monazite and xenotime with minor or trace amounts of LREE in xenotime grains (6.0 wt%). LREE (>95 mol% LREE) and less than 5 mol% HREE + Y reflects the enrichment of chondrite-normalized REE of the monazite grains of the Kymi granite stock. The xenotime grains (small and irregular) main composition contains 71 - 76 mol% YPO4, 16 - 27 mol% HREE, and 6 - 8 mol% LREE. It is believed that indium and REE-mineralization presence is due to the combination of magmatic and postmagmatic processes, particularly at later stages by fluid fractionation. 展开更多
关键词 INDIUM Roquesite REE-Minerals Kymi stock FINLAND
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Survey of feature selection and extraction techniques for stock market prediction 被引量:2
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作者 Htet Htet Htun Michael Biehl Nicolai Petkov 《Financial Innovation》 2023年第1期667-691,共25页
In stock market forecasting,the identification of critical features that affect the performance of machine learning(ML)models is crucial to achieve accurate stock price predictions.Several review papers in the literat... In stock market forecasting,the identification of critical features that affect the performance of machine learning(ML)models is crucial to achieve accurate stock price predictions.Several review papers in the literature have focused on various ML,statistical,and deep learning-based methods used in stock market forecasting.However,no survey study has explored feature selection and extraction techniques for stock market forecasting.This survey presents a detailed analysis of 32 research works that use a combination of feature study and ML approaches in various stock market applications.We conduct a systematic search for articles in the Scopus and Web of Science databases for the years 2011–2022.We review a variety of feature selection and feature extraction approaches that have been successfully applied in the stock market analyses presented in the articles.We also describe the combination of feature analysis techniques and ML methods and evaluate their performance.Moreover,we present other survey articles,stock market input and output data,and analyses based on various factors.We find that correlation criteria,random forest,principal component analysis,and autoencoder are the most widely used feature selection and extraction techniques with the best prediction accuracy for various stock market applications. 展开更多
关键词 Feature selection Feature extraction Dimensionality reduction stock market forecasting Machine learning
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The effect of financial ratios, firm size, and cash flow from operating activities in the interim report to the stock return 被引量:1
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作者 Dwi Martani Mulyono Rahfiani Khairurizka 《Chinese Business Review》 2009年第6期44-55,共12页
The objective of this study is to examine the value relevance of accounting information in explaining stock return. The study uses profitability, liquidity, leverage, market ratio, size and cash flow as proxies of acc... The objective of this study is to examine the value relevance of accounting information in explaining stock return. The study uses profitability, liquidity, leverage, market ratio, size and cash flow as proxies of accounting information. Cumulative abnormal return and market adjusted return are used as stock return variables. The samples of the study are listed companies in manufacturing industries that actively trading between 2003-2006 in Indonesia Stock Market. The study finds that profitability, turnover and market ratio has significant impact to the stock return. The result consistent with previous studies Hobart (2006), Utama and Santoso (1998) and Restraningsih (2007). 展开更多
关键词 financial ratio stock retum Indonesia stock Market
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The interaction between stock prices and interest rates in Turkey:empirical evidence from ARDL bounds test cointegration 被引量:1
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作者 Turgut Tursoy 《Financial Innovation》 2019年第1期110-121,共12页
This paper demonstrates a significant,long-running relationship between stock prices and domestic interest rates in Turkey’s financial markets for the period of 2001 M1-2017 M4.Cointegration analysis is investigated ... This paper demonstrates a significant,long-running relationship between stock prices and domestic interest rates in Turkey’s financial markets for the period of 2001 M1-2017 M4.Cointegration analysis is investigated using the autoregressivedistributed lag bounds(ARDL Bounds)test and vector autoregressive cointegration.Additionally,cointegrating equations such as the fully modified ordinary least square,dynamic ordinary least squares,and canonical cointegrating regression are applied to check the long-run elasticities in the concerned relationship.The ARDL Bounds and Johansen Cointegration test results show that,dynamically,both prices are significantly related to each other.The cointegrating equation outcomes demonstrate elasticities whereby both coefficients have negative signs.Additionally,the same results are corroborated by the impulse response where all variables respond negatively to each other. 展开更多
关键词 stock price Interest rates COINTEGRATION ARDL VAR
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Pandemic or panic?A firm-level study on the psychological and industrial impacts of COVID-19 on the Chinese stock market 被引量:1
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作者 Qiuyun Wang Lu Liu 《Financial Innovation》 2022年第1期643-680,共38页
This study presents a thorough investigation of the relationship between the coronavirus disease 2019(COVID-19)and daily stock price changes.We use several types of COVID-19 patients as indicators for exploring whethe... This study presents a thorough investigation of the relationship between the coronavirus disease 2019(COVID-19)and daily stock price changes.We use several types of COVID-19 patients as indicators for exploring whether stock prices are significantly affected by COVID-19’s impact.In addition,using the Chinese stock market as an example,we are particularly interested in the psychological and industrial impacts of COVID-19 on the financial market.This study makes two contributions to the literature.First,from a theoretical perspective,it shows a novel quantitative relationship between the psychological response to the pandemic and stock prices.In addition,it depicts the mechanism of the shock to the stock market by pointing out the specific functional expression of the impulse reaction.To our knowledge,this is the first theoretical calculation of the impulse of a shock to the financial market.Second,this study empirically estimates the marginal effect of the COVID-19 pandemic on fluctuations in stock market returns.By controlling for stock fundamentals,this study also estimates diverse industrial responses to pandemic stock volatility.We confirm that the COVID-19 pandemic has caused panic in the stock market,which not only depresses stock prices but also inflates volatility in daily returns.Regarding the impulse of the shock,we identify the cumulative level of the pandemic variables as well as their incremental differences.As shown by our empirical results,the terms for these differences will eventually dominate the marginal effect,which confirms the fading impulse of the shock.Finally,this study highlights some important policy implications of stock market volatility and returns to work in the industry. 展开更多
关键词 Black swan event COVID-19 Psychological and industrial impacts SHOCKS stock market reaction
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A chemical-reaction-optimization-based neuro-fuzzy hybrid network for stock closing price prediction 被引量:1
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作者 Sarat Chandra Nayak Bijan Bihari Misra 《Financial Innovation》 2019年第1期645-678,共34页
Accurate prediction of stock market behavior is a challenging issue for financial forecasting.Artificial neural networks,such as multilayer perceptron have been established as better approximation and classification m... Accurate prediction of stock market behavior is a challenging issue for financial forecasting.Artificial neural networks,such as multilayer perceptron have been established as better approximation and classification models for this domain.This study proposes a chemical reaction optimization(CRO)based neuro-fuzzy network model for prediction of stock indices.The input vectors to the model are fuzzified by applying a Gaussian membership function,and each input is associated with a degree of membership to different classes.A multilayer perceptron with one hidden layer is used as the base model and CRO is used to the optimal weights and biases of this model.CRO was chosen because it requires fewer control parameters and has a faster convergence rate.Five statistical parameters are used to evaluate the performance of the model,and the model is validated by forecasting the daily closing indices for five major stock markets.The performance of the proposed model is compared with four state-of-art models that are trained similarly and was found to be superior.We conducted the Deibold-Mariano test to check the statistical significance of the proposed model,and it was found to be significant.This model can be used as a promising tool for financial forecasting. 展开更多
关键词 Artificial neural network Neuro-fuzzy network Multilayer perceptron Chemical reaction optimization stock market forecasting Financial time series forecasting
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