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The Impact of Early Postoperative Rehabilitation Training on Balance Ability and Quality of Life in Elderly Patients with Hip Fracture
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作者 Kaiyu Yang Xiaofang Peng Li Xu 《Journal of Clinical and Nursing Research》 2026年第1期394-399,共6页
Objective:To analyze the improvement effect of early postoperative rehabilitation training on balance ability and quality of life in elderly patients with hip fracture.Methods:A total of 50 elderly patients with hip f... Objective:To analyze the improvement effect of early postoperative rehabilitation training on balance ability and quality of life in elderly patients with hip fracture.Methods:A total of 50 elderly patients with hip fracture admitted to our hospital from January 2023 to January 2024 were selected and divided into the observation group(25 cases)and the control group(25 cases)by random number table method.The control group received routine nursing,while the observation group received early rehabilitation training on the basis of routine nursing.The balance ability(Berg Balance Scale,BBS)and quality of life(SF-36)of the two groups were compared.Results:The BBS scores of the observation group at all postoperative time points were significantly higher than those of the control group(p<0.05),and the quality-of-life scores of the observation group were also significantly higher than those of the control group(p<0.05).Conclusion:Early postoperative rehabilitation training for elderly patients with hip fracture can improve their balance ability,enhance their quality of life,and reduce the incidence of postoperative complications,which is worthy of clinical promotion. 展开更多
关键词 Elderly hip fracture Early postoperative rehabilitation training Balance ability Quality of life COMPLICATIONS
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Evaluation of cropland suitability and key potential areas on the Qinghai-Tibet Plateau
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作者 YANG Hua XU Yong +1 位作者 LI Jiuyi ZHOU Kan 《Journal of Geographical Sciences》 2025年第4期800-820,共21页
Cropland suitability analysis is a vital tool for ensuring food security and sustainable agriculture,coordinating ecological space with human activity space on the Qinghai-Tibet Plateau(QTP).However,there are few stud... Cropland suitability analysis is a vital tool for ensuring food security and sustainable agriculture,coordinating ecological space with human activity space on the Qinghai-Tibet Plateau(QTP).However,there are few studies on complete and accurate cropland suitability assessments on the QTP,let alone on identifying key potential areas for cropland development.We used a novel assessment model to generate a 30-m cropland suitability map for the QTP.The identification of areas with cropland development potential and the evaluation of potentially available cropland were further integrated into a unified analytical framework.We found that only 10.18%of the study area is suitable for large-scale and permanent cropland.Moreover,approximately 72.75%of the existing cropland was found to be distributed in suitable or marginally suitable areas.Considering the trade-offs related to irrigation water supply convenience,approximately 1.07%of the study area was identified as having high potential for cropland development.Four key potential areas were further identified:the Shannan Valley,the Nyingchi Valley,the Zanda Valley,and the Gonghe Basin.These areas boast abundant potentially available cropland resources and ecological resettlement capacities,which leads us to recommend strategic priorities for comprehensive land consolidation and water development.This study has practical significance for optimizing land resource allocation and guiding decision-making related to ecological migration on the QTP. 展开更多
关键词 land resources cropland suitability key potential areas potentially available cropland QinghaiTibet Plateau
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Community Engagement as a Mediator between Land Suitability and Investment in Facilities on Tourism Potential in Huangma Village,China
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作者 Ling Cai Zaharah Mohd Yusoff Nor Aizam Adnan 《Journal of Environmental & Earth Sciences》 2025年第7期299-316,共18页
This study examines the influence of land suitability and investment in facilities on tourism potential,with a particular focus on the mediating role of community engagement.While previous research has explored the im... This study examines the influence of land suitability and investment in facilities on tourism potential,with a particular focus on the mediating role of community engagement.While previous research has explored the impact of environmental and infrastructural factors on tourism development,few studies have examined the interactive effects of community engagement in maximizing these benefits.This study aims to fill this gap by providing empirical evidence from Huangma Village,Jiangxi Province,China.A quantitative research design was adopted,using Partial Least Squares-Structural Equation Modeling(PLS-SEM)in SmartPLS to test the hypothesized relationships.Data were collected from 231 respondents,including local residents,tourism business owners,government officials,and infrastructure developers,through a structured survey questionnaire.The results confirm that land suitability and infrastructure investment significantly enhance tourism potential,with community engagement playing a crucial mediating role.The findings suggest that tourism success depends not only on physical and economic factors but also on active local participation in tourism-related initiatives.This study contributes to the literature by integrating environmental,infrastructural,and social dimensions of tourism development.The findings offer practical insights for policymakers and tourism planners,emphasizing the need for sustainable land management,strategic infrastructure investment,and participatory tourism governance to maximize tourism potential. 展开更多
关键词 Land Suitability Infrastructure Investment Community Engagement Tourism potential Sustainable Tourism
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Study of the potential predictability of ENSO with different phases and intensities in the CESM
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作者 Le Zhang Ting Liu Dake Chen 《Acta Oceanologica Sinica》 2025年第8期1-9,共9页
The inherent asymmetry and diversity of the El Niño-Southern Oscillation(ENSO)pose substantial challenges to its prediction.Potential predictability measures the upper limit of predictability for a certain event.... The inherent asymmetry and diversity of the El Niño-Southern Oscillation(ENSO)pose substantial challenges to its prediction.Potential predictability measures the upper limit of predictability for a certain event.Assessing the potential predictability of ENSO across varying phases and intensities with sophisticated climate models is crucial for understanding the upper limits of forecasting capabilities and identifying room for future enhancement.Based on the hindcast dataset with a recently developed ensemble forecasting system(the community earth system model,CESM),this study comprehensively investigates potential predictability for ENSO across different phases and intensities.The findings reveal that La Niña events possess higher potential predictability relative to their El Niño counterparts.Strong events exhibit significantly higher potential predictability than weak events within the same phase.The potential predictability of distinct ENSO types is primarily influenced by the seasonal variation inherent to their predictability.Regardless of the event classification,the potential predictability is characterized by a rapid decline from spring onwards,with the apex of this decline occurring in summer.The intensity of the seasonal predictability barrier inversely correlates with the upper limit of potential predictability.Specifically,a weaker(stronger)seasonal barrier is associated with a higher(lower)potential predictability.In addition,there is significant interdecadal variability both in the predictability of warm and cold ENSO events.The potential predictability for La Niña events decreases more slowly with increasing lead months,particularly in recent decades,resulting in an overall higher upper limit of potential predictability for La Niña events than for El Niño events over the past century.Nevertheless,El Niño events have also maintained a high potential predictability.This suggests substantial potential for improvement in future prediction for both. 展开更多
关键词 El Niño La Niña potential predictability forecast barriers INTERDECADAL
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Oilfield sustainability and management:An optimization model for the reconstruction of oil and gas gathering systems based on potential location mining
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作者 Jie Chen Wei Wang +2 位作者 Wen-Yuan Sun Dong Li Yu-Bo Jiao 《Petroleum Science》 2025年第2期935-955,共21页
The carbon emissions and cost during the construction phase are significant contributors to the oilfield lifecycle.As oilfields enter the late stage,the adaptability of facilities decreases.To achieve sustainable deve... The carbon emissions and cost during the construction phase are significant contributors to the oilfield lifecycle.As oilfields enter the late stage,the adaptability of facilities decreases.To achieve sustainable development,oilfield reconstruction was usually conducted in discrete rather than continuous space.Motivated by economic and sustainability goals,a 3-phase heuristic model for oilfield reconstruction was developed to mine potential locations in continuous space.In phase 1,considering the process characteristics of the oil and gas gathering system,potential locations were mined in continuous space.In phase 2,incorporating comprehensive reconstruction measures,a reconstruction model was established in discrete space.In phase 3,the topology was further adjusted in continuous space.Subsequently,the model was transformed into a single-objective mixed integer linear programming model using the augmented ε-constraint method.Numerical experiments revealed that the small number of potential locations could effectively reduce the reconstruction cost,and the quality of potential locations mined in phase 1 surpassed those generated in random or grid form.Case studies showed that cost and carbon emissions for a new block were reduced by up to 10.45% and 7.21 %,respectively.These reductions were because the potential locations mined in 1P reduced the number of metering stations,and 3P adjusted the locations of metering stations in continuous space to shorten the pipeline length.For an old oilfield,the load and connection ratios of the old metering station increased to 89.7% and 94.9%,respectively,enhancing operation efficiency.Meanwhile,recycling facilitated the diversification of reconstruction measures and yielded a profit of 582,573 ¥,constituting 5.56% of the total cost.This study adopted comprehensive reconstruction measures and tapped into potential reductions in cost and carbon emissions for oilfield reconstruction,offering valuable insights for future oilfield design and construction. 展开更多
关键词 Oilfield reconstruction Sustainable development Optimization model potential location3-phase heuristic model
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NPP vulnerability of the potential vegetation of China to climate change in the past and future 被引量:28
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作者 YUAN Quanzhi WU Shaohong +3 位作者 DAI Erfu ZHAO Dongsheng REN Ping ZHANG Xueru 《Journal of Geographical Sciences》 SCIE CSCD 2017年第2期131-142,共12页
Using the Integrated Biosphere Simulator, a dynamic vegetation model, this study initially simulated the net primary productivity(NPP) dynamics of China's potential vegetation in the past 55 years(1961–2015) and... Using the Integrated Biosphere Simulator, a dynamic vegetation model, this study initially simulated the net primary productivity(NPP) dynamics of China's potential vegetation in the past 55 years(1961–2015) and in the future 35 years(2016–2050). Then, taking the NPP of the potential vegetation in average climate conditions during 1986–2005 as the basis for evaluation, this study examined whether the potential vegetation adapts to climate change or not. Meanwhile, the degree of inadaptability was evaluated. Finally, the NPP vulnerability of the potential vegetation was evaluated by synthesizing the frequency and degrees of inadaptability to climate change. In the past 55 years, the NPP of desert ecosystems in the south of the Tianshan Mountains and grassland ecosystems in the north of China and in western Tibetan Plateau was prone to the effect of climate change. The NPP of most forest ecosystems was not prone to the influence of climate change. The low NPP vulnerability to climate change of the evergreen broad-leaved and coniferous forests was observed. Furthermore, the NPP of the desert ecosystems in the north of the Tianshan Mountains and grassland ecosystems in the central and eastern Tibetan Plateau also had low vulnerability to climate change. In the next 35 years, the NPP vulnerability to climate change would reduce the forest–steppe in the Songliao Plain, the deciduous broad-leaved forests in the warm temperate zone, and the alpine steppe in the central and western Tibetan Plateau. The NPP vulnerability would significantly increase of the temperate desert in the Junggar Basin and the alpine desert in the Kunlun Mountains. The NPP vulnerability of the subtropical evergreen broad-leaved forests would also increase. The area of the regions with increased vulnerability would account for 27.5% of China. 展开更多
关键词 climate change VULNERability potential vegetation net primary productivity IBIS China
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Study on Moist Potential Vorticity and Symmetric Instabilityduring a Heavy Rain Event Occurred inthe Jiang-Huai Valleys 被引量:15
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作者 寿绍文 李耀辉 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1999年第2期314-321,共8页
In the light of the theory on moist potential vorticity (MPV) investigation was undertaken of the 700 hPa vertical (horizontal) component MP1 (MPV2) for the heavy rain event occurring in July 5–6, 1991. Results show ... In the light of the theory on moist potential vorticity (MPV) investigation was undertaken of the 700 hPa vertical (horizontal) component MP1 (MPV2) for the heavy rain event occurring in July 5–6, 1991. Results show that the distribution features of the two components were closely related to the development of a mesoscale cyclone as a rainstorm-causing weather system in the lower troposphere in such a way that the ambient atmosphere of which MPV1 > 0 and MPV2 < 0 with |MPV1| ≥ |MPV2| favored the genesis of conditional symmetric instability (CSI) and that, as indicated by calculations, a CSI sector was really existent in the lower troposphere during the heavy rain happening and contributed greatly to its development. 展开更多
关键词 Heavy rain Moist potential vorticity (MPV) Conditional symmetric instability
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Yield potential and stability in super hybrid rice and its production strategies 被引量:18
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作者 HUANG Min TANG Qi-yuan +1 位作者 AO He-jun ZOU Ying-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第5期1009-1017,共9页
China's Super Hybrid Rice Breeding Program has made significant progress over the past two decades. In this paper, we reviewed our studies on the yield potential and stability in super hybrid rice and discussed the s... China's Super Hybrid Rice Breeding Program has made significant progress over the past two decades. In this paper, we reviewed our studies on the yield potential and stability in super hybrid rice and discussed the strategies for super hybrid rice production. The results of our studies show that rice yield potential has been increased by 12% in super hybrid cultivars as compared with ordinary hybrid and inbred cultivars. The higher grain yields in super hybrid rice cultivars are attributed to larger panicle size coupled with higher biomass production or higher harvest index. However, grain yields in super hybrid rice cultivars vary widely among locations depending on soil and climatic factors. Therefore, it is important to tailor target yield to local conditions in super hybrid rice production. The target yield for super hybrid rice production can be determined by the average yield method or the regression model method. Improving soil quality is critical to achieving the target yield in super hybrid rice production. Favorable crop rotations such as rice-oilseed rape and novel soil management practices, such as biochar addition, are effective approaches to improve soil quality. It is needed to develop simplified cultivation tech- nologies for super hybrid rice to meet the changes in socioeconomic environments during the period of transition. There are such technologies as no-tillage direct seeding and mechanized transplanting at high hill density with single seedling per hill. 展开更多
关键词 mechanized transplanting no-tillage direct seeding super hybrid rice target yield yield potential yield stability
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Potential and Suitability Evaluation of CO_2 Geological Storage in Major Sedimentary Basins of China,and the Demonstration Project in Ordos Basin 被引量:10
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作者 GUO Jianqiang WEN Dongguang +4 位作者 ZHANG Senqi XU Tianfu LI Xufeng DIAO Yujie JIA Xiaofeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第4期1319-1332,共14页
From 2010 to 2012, the China Geological Survey Center for Hydrogeology and Environmental Geology Survey (CHEGS) carried out the project "Potential evaluation and demonstration project of CO2 Geological Storage in C... From 2010 to 2012, the China Geological Survey Center for Hydrogeology and Environmental Geology Survey (CHEGS) carried out the project "Potential evaluation and demonstration project of CO2 Geological Storage in China". During this project, we developed an evaluation index system and technical methods for the potential and suitability of CO2 geological storage based on China's geological conditions, and evaluated the potential and suitability of the primary basins for COz geological storage, in order to draw a series of regional scale maps (at a scale of 1:5000000) and develop an atlas of the main sedimentary basins in China. By using these tools, we delineated many potential targets for CO2 storage. We also built techniques and methods for site selection and the exploration and assessment of CO2 geological storage in deep saline aquifers. Furthermore, through cooperation with the China Shenhua Coal to Liquid and Chemical Co., Ltd., we successfully constructed the first coal-based demonstration project for CO2 geological storage in deep saline aquifers in the Yijinhuoluo Banner of Ordos in the Inner Mongolia Autonomous Region, which brought about the basic preliminary theories, techniques, and methods of geological CO2 storage in deep saline aquifers under China's geological conditions. 展开更多
关键词 C02 geological storage potential and suitability evaluation ATLAS demonstration project
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Effects of Chronic Administration of Melatonin on Spatial Learning Ability and Long-term Potentiation in Lead-exposed and Control Rats 被引量:4
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作者 XIU-JING CAO MING WANG +3 位作者 WEI-HENG CHEN DA-MIAO ZHU JIA-QI SHE DI-YUN RUAN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第1期70-75,共6页
Objective To explore the changes in spatial learning performance and long-term potentiation (LTP) which is recognized as a component of the cellular basis of learning and memory in normal and lead-exposed rats after... Objective To explore the changes in spatial learning performance and long-term potentiation (LTP) which is recognized as a component of the cellular basis of learning and memory in normal and lead-exposed rats after administration of melatonin (MT) for two months. Methods Experiment was performed in adult male Wistar rats (12 controls, 12 exposed to melatonin treatment, 10 exposed to lead and 10 exposed to lead and melatonin treatment). The lead-exposed rats received 0.2% lead acetate solution from their birth day while the control rats drank tap water. Melatonin (3 mg/kg) or vehicle was administered to the control and lead-exposed rats from the time of their weaning by gastric gavage each day for 60 days, depending on their groups. At the age of 81-90 days, all the animals were subjected to Morris water maze test and then used for extracellular recording of LTP in the dentate gyrus (DG) area of the hippocampus in vivo. Results Low dose of melatonin given from weaning for two months impaired LTP in the DG area of hippocampus and induced learning and memory deficit in the control rats. When melatonin was administered over a prolonged period to the lead-exposed rats, it exacerbated LTP impairment, learning and memory deficit induced by lead. Conclusion Melatonin is not suitable for normal and lead-exposed children. 展开更多
关键词 MELATONIN LEAD Learning MEMORY Long-term potentiation (LTP)
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Combining Ability and Breeding Potential of Rapeseed Elite Lines for Pod Shatter Resistance 被引量:4
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作者 LIU Jia MEI De-sheng +5 位作者 LI Yun-chang CUI Jia-cheng WANG Hui PENG Peng-fei FU Li HU Qiong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第3期552-555,共4页
Pod shatter resistance of rapeseed is of great importance for modem farming practice. In order to determine the combining ability of elite inbred lines and the breeding potential of rapeseed hybrids in terms of pod sh... Pod shatter resistance of rapeseed is of great importance for modem farming practice. In order to determine the combining ability of elite inbred lines and the breeding potential of rapeseed hybrids in terms of pod shatter resistance, analysis of a 6×6 incomplete diallel cross was conducted at two locations. Results showed that a significant variation existed among breeding lines and their F1 hybrids for pod shatter resistant index (SRI), pod length and width. Pod shatter resistance was significantly positively correlated with pod length. The general combining ability (GCA) effects (GCA=l.58) played a more important role than specific combining ability (SCA) effects (SCA=0.20) for pod shatter trait. The elite lines R1, 1019B and 1055B displayed significant positive GCA effects for pod shatter resistance. Four crosses (1019B×R1, 1015B×R1, 6098B×R1, and 8908B×R1) with high mean performance and positive SCA effects were recommended for developing new hybrids for mechanical harvest in the middle reaches of the Yangtze River. 展开更多
关键词 RAPESEED pod shatter resistance elite lines breeding potential
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A New Parameter of Cleanability to Determine the Clean Potential of Coal Resources 被引量:4
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作者 TANG Yuegang YANG Shuting WANG Xiaoshuai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2338-2339,共2页
Objective This work is based on analysis on large numbers of coal data such as the latest national coal potential evaluation data and previous data published by REN Deyi, TANG Xiuyi and LU Xukun, and the evaluation m... Objective This work is based on analysis on large numbers of coal data such as the latest national coal potential evaluation data and previous data published by REN Deyi, TANG Xiuyi and LU Xukun, and the evaluation methods of clean potential of coal resources proposed by predecessors. It is found that previous method rank coal is only in accordance with raw coal or washed coal, which fail to take full account of the changes in elements before and after coal washing. Some elements can be removed by washing or other methods, and others may be even enriched after the coal is washed. For this reason, this work defined a new parameter of cleanability and developed its calculation formula to determine the clean potential of coal resources. Cleanability is a comprehensive indicator based on the removal rate of each indicator harmful element in coal. The clean potential of coal is proportional to the value of cleanability. The higher the cleanability value is, the better the clean potential is, and vice versa. 展开更多
关键词 Cleanability to Determine the Clean potential of Coal
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Comparative genomics study between high and low laying goose breeds reveals the important role of ESR1 in laying ability 被引量:1
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作者 Qingyuan Ouyang Hengli Xie +8 位作者 Shenqiang Hu Cong Lan Mingxia Ran Jiwei Hu HuaHe Liang Li Hehe Liu Hao Qu Jiwen Wang 《Journal of Integrative Agriculture》 2025年第3期1167-1180,共14页
The low egg production of goose greatly limits the development of the industry.China possesses the most abundant goose breeds resources.In this study,genome resequencing data of swan goose(Anser cygnoides)and domestic... The low egg production of goose greatly limits the development of the industry.China possesses the most abundant goose breeds resources.In this study,genome resequencing data of swan goose(Anser cygnoides)and domesticated high and low laying goose breeds(Anser cygnoides domestiation)were used to identify key genes related to egg laying ability in geese and verify their functions.Selective sweep analyses revealed 416 genes that were specifically selected during the domestication process from swan geese to high laying geese.Furthermore,SNPs and Indels markers were used in GWAS analyses between high and low laying breed geese.The results showed that RTCB,BPIFC,SYN3,SYNE1,VIP,and ESR1 may be related to the differences in laying ability of geese.Notably,only ESR1 was identified simultaneously by GWAS and selective sweep analysis.The genotype of Indelchr3:54429172,located downstream of ESR1,was confirmed to affect the expression of ESR1 in the ovarian stroma and showed significant correlation with body weight at first egg and laying frequency of geese.CCK-8,EdU,and flow cytometry confirmed that ESR1 can promote the apoptosis of goose pre-hierarchical follicles ganulosa cells(phGCs)and inhibit their proliferation.Combined with transcriptome data,it was found ESR1 involved in the function of goose phGCs may be related to MAPK and TGF-beta signaling pathways.Overall,our study used genomic information from different goose breeds to identify an indel located in the downstream of ESR1 associated with goose laying ability.The main pathways and biological processes of ESR1 involved in the regulation of goose laying ability were identified by cell biology and transcriptomics methods.These results are helpful to further understand the laying ability characteristics of goose and improve the egg production of geese. 展开更多
关键词 GOOSE laying ability GENOME ESR1
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An Empirical Study on the Reflective Feedback Model Based on Pedagogical Agents to Improve Students’ Problem-Solving Ability 被引量:1
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作者 Hui-Lin Zhang Jun-Jie Yan +4 位作者 Jing Liu Zhuo-Cen Zou Qun-Fang Zeng Yu-Lu Jin Jian-Nan Wu 《教育技术与创新》 2025年第1期66-75,共10页
This study constructs a reflective feedback model based on a pedagogical agent(PA)and explores its impact on students’problem-solving ability and cognitive load.A quasi-experimental design was used in the study,with ... This study constructs a reflective feedback model based on a pedagogical agent(PA)and explores its impact on students’problem-solving ability and cognitive load.A quasi-experimental design was used in the study,with 84 students from a middle school selected as the research subjects(44 in the experimental group and 40 in the control group).The experimental group used the reflective feedback model,while the control group used the factual feedback model.The results show that,compared with factual feedback,the reflective feedback model based on the pedagogical agent significantly improves students’problem-solving ability,especially at the action and thinking levels.In addition,this model effectively reduces students’cognitive load,especially in terms of internal and external load. 展开更多
关键词 pedagogical agent problem-solving ability reflective feedback
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Reliability of dermatomal somatosensory-evoked potential in the evaluation of lumbosacral nerve root injury A concurrent case-control study 被引量:2
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作者 Ningjiang Shen Jian Chen Guangji Wang Xiaoli Wu Yutian Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第1期57-60,共4页
BACKGROUND: It has been reported that dermatomal somatosensory evoked potential (DSEP) can be used for diagnosing nerve root injury in patients with lumbar disc herniation (LDH), and that 83% 95% of patients suff... BACKGROUND: It has been reported that dermatomal somatosensory evoked potential (DSEP) can be used for diagnosing nerve root injury in patients with lumbar disc herniation (LDH), and that 83% 95% of patients suffer from the disease. Body height correction is not performed prior to determinations of latency and latency difference between the healthy and affected sides. However, latency noticeably correlates to body height. OBJECTIVE: This study aims to determine the lumbosacral nerve root injury in patients with LDH by DSEP, and to evaluate the sensitivity of the DSEP difference between the healthy and affected sides using a diagnostic index following body height correction. DESIGN: A case-control observation. SETTING: Department of Orthopedic Surgery, Hainan Provincial People's Hospital. PARTICIPANTS: Ninety-six patients, comprised of 67 males and 29 females, with an average age of 43 years and a mean body height of 1.65 m (range 1.48-1.81 m), were recruited for this study. These patients suffered from unilateral lower limb radiation pain and received treatment at the Department of Orthopedic Surgery, Hainan Provincial People's Hospital between January 2004 and December 2006. All patients were confirmed to suffer from LDH at the L3-4, L-5, and/or Ls-SI by CT and/or MRI examinations. Central nervous system diseases were excluded. In order to obtain a normal reference value, DSEP was determined for a group of 50 subjects, who concurrently received health examinations in the same department. The subjects had no previous history of back leg pain or nervous system disease. The group of healthy controls included 26 males and 24 females, with an average age of 37 years and a mean body height of 1.63 m (range 1.50-1.80 m). Written informed consent was obtained from all subjects for laboratory samples. The protocol was approved by the Hospital's Ethics Committees. DSEP was determined with myoelectricity-evoked potential equipment (Keypoint, Batch No. 9020A0042591, Dantec Company, Denmark). METHODS: DSEP of patients with LDH was determined. Constant-voltage square pulse stimulation was used to determine DSEP, with the following parameters: a pulse wave width of 0.2 milliseconds; a saddle-like stimulating electrode; a stimulation intensity 3 times greater than the sensation threshold; a stimulation frequency of 1.5 Hz; mean superposition greater than 100 times; and inter-electrode impedance 〈 5 k Q. The stimulation point was a skin key sensation point confirmed by the American Spinal Injury Association, i.e. L4 at medial malleolus, L5 at the third metatarsophalangeal joint on the dorsum of the foot, and SI at the lateral heel. The recording electrode was a needle electrode, the recording point was Cz, and the reference electrode was Fz. DSEP latency of P40, and latency differences of P40, between the healthy side and the affected side, were determined. DSEP at L4, L5, and S1 nerve roots of the lower limbs of 50 healthy controls were bilaterally determined. The normal values of P40 latency and P40 N50 amplitude were statistically obtained. MAIN OUTCOME MEASURES: Determination of DSEP values. RESULTS: Ninety-six patients with LDH and fifty healthy controls participated in the final analysis. In the healthy controls, the amplitude of DSEP varied greatly, with a mean amplitude co-efficient of variation of 58% for L4, L5, and SI dermatomes. P40 latency was stable, with a mean latency coefficient of variation of 4.7%. In patients with LDH, the P40 wave disappeared. P40 latency was 2.5 times prolonged compared to normal mean value. P40 latency difference between the healthy and the affected side was 2.5 times higher than the normal mean value of the healthy side. CONCLUSION: DSEP can reflect the functional status of lumbosacral nerve root. P40 latency difference between the healthy side and the affected side is the most sensitive diagnosis index for patients with LDH suffering from unilateral lower limb radiation pain. 展开更多
关键词 dermatomal somatosensory evoked potential lumbar disc herniation nerve root injury
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Spatial distribution of the potential forest biomass availability in Europe 被引量:1
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作者 Pieter Johannes Verkerk Joanne Brighid Fitzgerald +4 位作者 Pawan Datta Matthias Dees Geerten Martijn Hengeveld Marcus Lindner Sergey Zudin 《Forest Ecosystems》 SCIE CSCD 2019年第1期56-66,共11页
Background: European forests are considered a crucial resource for supplying biomass to a growing bio-economy in Europe. This study aimed to assess the potential availability of forest biomass from European forests an... Background: European forests are considered a crucial resource for supplying biomass to a growing bio-economy in Europe. This study aimed to assess the potential availability of forest biomass from European forests and its spatial distribution. We tried to answer the questions(i) how is the potential forest biomass availability spatially distributed across Europe and(ii) where are hotspots of potential forest biomass availability located?Methods: The spatial distribution of woody biomass potentials was assessed for 2020 for stemwood, residues(branches and harvest losses) and stumps for 39 European countries. Using the European Forest Information SCENario(EFISCEN) model and international forest statistics, we estimated the theoretical amount of biomass that could be available based on the current and future development of the forest age-structure, growing stock and increment and forest management regimes. We combined these estimates with a set of environmental(site productivity, soil and water protection and biodiversity protection) and technical(recovery rate, soil bearing capacity) constraints, which reduced the amount of woody biomass that could potentially be available. We mapped the potential biomass availability at the level of administrative units and at the 10 km × 10 km grid level to gain insight into the spatial distribution of the woody biomass potentials.Results: According to our results, the total availability of forest biomass ranges between 357 and 551 Tg dry matter per year. The largest potential supply of woody biomass per unit of land can be found in northern Europe(southern Finland and Sweden, Estonia and Latvia), central Europe(Austria, Czech Republic, and southern Germany),Slovenia, southwest France and Portugal. However, large parts of these potentials are already used to produce materials and energy. The distribution of biomass potentials that are currently unused only partially coincides with regions that currently have high levels of wood production.Conclusions: Our study shows how the forest biomass potentials are spatially distributed across the European continent, thereby providing insight into where policies could focus on an increase of the supply of woody biomass from forests. Future research on potential biomass availability from European forests should also consider to what extent forest owners would be willing to mobilise additional biomass from their forests and at what costs the estimated potentials could be mobilised. 展开更多
关键词 FOREST BIOMASS EFISCEN EUROPE potentiAL supply Spatial distribution
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Cultivation of Students’Critical Thinking Ability in College English Audio-Visual and Oral Teaching 被引量:1
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作者 Hui Zhang 《Journal of Contemporary Educational Research》 2025年第6期36-41,共6页
With the increasingly prominent trend of globalization,English,as the common language of international communication,plays an increasingly important role in university education.As a key link in English teaching,the c... With the increasingly prominent trend of globalization,English,as the common language of international communication,plays an increasingly important role in university education.As a key link in English teaching,the college English audio-visual oral course not only imparts language knowledge and skills,but also shoulders the important task of cultivating students’critical thinking.As one of the essential core qualities of modern talents,critical thinking ability plays an irreplaceable role in students’in-depth understanding of English knowledge,improving intercultural communication ability and cultivating innovative thinking.This paper expounds the significance of cultivating students’critical thinking ability in college English audio-visual and oral teaching,and puts forward a series of innovative teaching strategies to cultivate students’critical thinking ability combined with practical teaching experience and cutting-edge education theory,in order to provide new ideas and practical guidance for the improvement of college English teaching quality and the development of students’comprehensive quality. 展开更多
关键词 Critical thinking ability College English Audio-visual and oral teaching
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Stability of trapped Bose-Einstein condensates in one-dimensional tilted optical lattice potential 被引量:1
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作者 方见树 廖湘萍 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期80-84,共5页
Using the direct perturbation technique, this paper obtains a general perturbed solution of the Bose-Einstein condensates trapped in one-dimensional tilted optical lattice potential. We also gave out two necessary and... Using the direct perturbation technique, this paper obtains a general perturbed solution of the Bose-Einstein condensates trapped in one-dimensional tilted optical lattice potential. We also gave out two necessary and sufficient conditions for boundedness of the perturbed solution. Theoretical analytical results and the corresponding numerical results show that the perturbed solution of the Bose-Einstein condensate system is unbounded in general and indicate that the Bose-Einstein condensates are Lyapunov-unstable. However, when the conditions for boundedness of the perturbed solution are satisfied, then the Bose-Einstein condensates are Lyapunov-stable. 展开更多
关键词 Bose-Einstein condensate CHAOS STability tilted optical lattice potential
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Spatial and temporal variability of soil water in drylands:plant water potential as a diagnostic tool 被引量:1
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作者 Maik VESTE Markus STAUDINGER Manfred KüPPERS 《Forestry Studies in China》 CAS 2008年第2期74-80,共7页
Arid and semi-arid regions are characterized by low rainfall and high potential evaporative demand. Here, water is the major limiting factor for plant growth and productivity. Soil and surface hydrology properties (e... Arid and semi-arid regions are characterized by low rainfall and high potential evaporative demand. Here, water is the major limiting factor for plant growth and productivity. Soil and surface hydrology properties (e.g. field capacity, infikration rates) effectively control the water re-distribution in the ecosystem, a fact that is aggravated in arid environments. Information of the spatial and temporal accessibility of soil water in desert ecosystems is limited. The purpose of the studies is the application of plant water potential to estimate the spatial and temporal variations of soil water availability in different arid ecosystems of the Negev (Israel) and southern Morocco. As model plants the evergreen shrubs Retama raetam, Thymelaea hirsuta and trees (Acacia tortilis) were chosen. Seasonal and spatial variations of the pre-dawn water potential (ψpd) were examined as diagnostic tool to determine water availability on the landscape level. The seasonal differences in the pre-dawn water potential were less pronounced on the dune compared to the interdune. This showed a better water availability on the dune slope. Also in the investigated wadis systems spatial differences of the water potential could be detected and related to the vegetation pattern. 展开更多
关键词 soil water PATTERN predawn potential deserts Nizzana NEGEV
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Potential Predictability of Sea Surface Temperature in a Coupled Ocean-Atmosphere GCM 被引量:1
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作者 严厉 王盘兴 +2 位作者 俞永强 李立娟 王斌 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第4期921-936,共16页
Using the Flexible Global Ocean-Atmosphere-Land System model (FGOALS) version g1.11, a group of seasonal hindcasting experiments were carried out. In order to investigate the potential predictability of sea surface ... Using the Flexible Global Ocean-Atmosphere-Land System model (FGOALS) version g1.11, a group of seasonal hindcasting experiments were carried out. In order to investigate the potential predictability of sea surface temperature (SST), singular value decomposition (SVD) analyses were applied to extract dominant coupled modes between observed and predicated SST from the hindcasting experiments in this study. The fields discussed are sea surface temperature anomalies over the tropical Pacific basin (20~0S-20~0N, 120~0E- 80~0W), respectively starting in four seasons from 1982 to 2005. On the basis of SVD analysis, the simulated pattern was replaced with the corresponding observed pattern to reconstruct SST anomaly fields to improve the ability of the simulation. The predictive skill, anomaly correlation coefficients (ACC), after systematic error correction using the first five modes was regarded as potential predictability. Results showed that: 1) the statistical postprocessing approach was effective for systematic error correction; 2) model error sources mainly arose from mode 2 extracted from the SVD analysis-that is, during the transition phase of ENSO, the model encountered the spring predictability barrier; and 3) potential predictability (upper limits of predictability) could be high over most of the tropical Pacific basin, including the tropical western Pacific and an extra 10-degrees region of the mid and eastern Pacific. 展开更多
关键词 coupled GCM hindcasting experiments SST singular value decomposition potential pre-dictability
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