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The Effect of Self-confidence in SLA
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作者 李艳 《英语广场(学术研究)》 2012年第11期22-25,共4页
Krashen's affective filter theory drew researchers' attention to the fresh field of internal factors of learners.But researchers seem to pay too much attention to the other factors while tending to neglect a f... Krashen's affective filter theory drew researchers' attention to the fresh field of internal factors of learners.But researchers seem to pay too much attention to the other factors while tending to neglect a factor that we cannot afford to play down in language learning research-self-confidence.This paper is designed to discuss the close relationship between self-confidence and some of the other important affective factors,and furthermore raise appropriate concern over self-confidence. 展开更多
关键词 affective factor self-confidence appropriate concern
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How to Strengthen Child Learners' Self-confidence
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作者 李文敬 《海外英语》 2013年第19期289-290,共2页
Self-confidence is closely related to L2 learning.In order to make their learners enjoy English learning,English teach ers need to strengthen the learners’English learning confidence.This article is to find out Engli... Self-confidence is closely related to L2 learning.In order to make their learners enjoy English learning,English teach ers need to strengthen the learners’English learning confidence.This article is to find out English teachers’role to strengthening learners’self-confidence in ELL by means of class observation.The writer concludes improving speaking ability;giving praise and offering gentle error correcting can help to strengthen the learners’confidence. 展开更多
关键词 CHILD LEARNER self-confidence ENGLISH learning
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Cultivation of Cultural Subjectivity from the Perspective of Cultural Self-Confidence 被引量:2
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作者 Liu Wenyuan 《学术界》 CSSCI 北大核心 2019年第10期207-215,共9页
Economic and cultural globalization has strong impacts on the culture of each country.How to maintain the integrity of the local culture in the course of globalization and how to develop on the basis of the inheritanc... Economic and cultural globalization has strong impacts on the culture of each country.How to maintain the integrity of the local culture in the course of globalization and how to develop on the basis of the inheritance and innovation are the questions worthy of being studied.This paper firstly expounds the important meaning of cultural subjectivity in the view of cultural self-confidence,then explores the roots for the loss of cultural subjectivity consciousness and finally indicates the strategies of cultivating cultural subjectivity.Cultivating cultural subjectivity is an effective way to maintain the integrity of the local culture and the cultural self-confidence. 展开更多
关键词 GLOBALIZATION CULTURE CULTURAL self-confidence CULTURAL SUBJECTIVITY
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On Cultural Self-Confidence and Communication from the Perspective of“Belt and Road”Initiative
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作者 Xia Ying Wang Yang 《学术界》 CSSCI 北大核心 2018年第12期249-259,共11页
An important part of the "Belt and Road " Initiative is to achieve people-to-people bonds. People-to-people bonds are certainly based on cultural self-confidence and cultural self-awareness. Cultural self-co... An important part of the "Belt and Road " Initiative is to achieve people-to-people bonds. People-to-people bonds are certainly based on cultural self-confidence and cultural self-awareness. Cultural self-confidence is an important cultural strategy put forward by the party and the country in the vision of contemporary society,and an important deployment to realize the great rejuvenation of the Chinese nation. This paper first gives a brief overview of the advantages of cultural self-confidence in external communication,and then analyzes the opportunities and challenges that cultural self-confidence faces in external communication in the newera. Finally,it focuses on exploration on the external communication ways of cultural self-confidence in the "Belt and Road"Initiative. O nly based on the deep understanding of local culture can we can shape the soul of culture in the process of further opening-up and external communication to the outside world,and enhance the cultural self-aw areness of the people; build a solid foundation of culture and promote cultural exchanges with other countries. 展开更多
关键词 “Belt and Road”Initiative people-to-people bonds cultural self-confidence external COMMUNICATION
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Cumulative effects of excess high-normal alanine aminotransferase levels in relation to new-onset metabolic dysfunction-associated fatty liver disease in China 被引量:7
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作者 Jing-Feng Chen Zhuo-Qing Wu +5 位作者 Hao-Shuang Liu Su Yan You-Xiang Wang Miao Xing Xiao-Qin Song Su-Ying Ding 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1346-1357,共12页
BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations ... BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations between repeated high-normal ALT measurements and the risk of new-onset MAFLD prospectively.METHODS A cohort of 3553 participants followed for four consecutive health examinations over 4 years was selected.The incidence rate,cumulative times,and equally and unequally weighted cumulative effects of excess high-normal ALT levels(ehALT)were measured.Cox proportional hazards regression was used to analyse the association between the cumulative effects of ehALT and the risk of new-onset MAFLD.RESULTS A total of 83.13%of participants with MAFLD had normal ALT levels.The incidence rate of MAFLD showed a linear increasing trend in the cumulative ehALT group.Compared with those in the low-normal ALT group,the multivariate adjusted hazard ratios of the equally and unequally weighted cumulative effects of ehALT were 1.651[95%confidence interval(CI):1.199-2.273]and 1.535(95%CI:1.119-2.106)in the third quartile and 1.616(95%CI:1.162-2.246)and 1.580(95%CI:1.155-2.162)in the fourth quartile,respectively.CONCLUSION Most participants with MAFLD had normal ALT levels.Long-term high-normal ALT levels were associated with a cumulative increased risk of new-onset MAFLD. 展开更多
关键词 Metabolic dysfunction-associated fatty liver disease High-normal alanine aminotransferase level Cumulative effect Cox proportional hazards regression Cohort study
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Handling the EFL Students' Crisis of Self-confidence to Ask Questions
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作者 Tono Suwartono Puspita Mayaratri 《Sino-US English Teaching》 2011年第1期24-31,共8页
It is no wonder that inquiring is an important skill. This paper deals with a research which was intended to see if respect and encouragement could solve the problem of students' self-confidence to inquire in the EFL... It is no wonder that inquiring is an important skill. This paper deals with a research which was intended to see if respect and encouragement could solve the problem of students' self-confidence to inquire in the EFL (English as a Foreign Language) classroom. The research involved a secondary group of students whose self-confidence to ask questions was considered low by the teacher and research collaborators. The data were collected through observation, questionnaire and interview. Based on a pre-observation, problem sources had been identified, i.e., the students were afraid of being thought of as "looking for sensation only", afraid that their classmates would laugh at them, worried of being judged as arrogant or pretentious, did not want to be considered stupid, and wondered if they could produce qualified questions. Teachers believed that fear of asking questions is part of the Indonesian students' culture. The research team agreed upon the way to handle the problem--by respect and encouragement procedure. The first session implementing the procedure was not successful enough in raising the students' self-confidence. Though students had already started to address some questions of this stage, their behaviors did not seem to be improved. They were still afraid, doubtful and unhappy with questioning, which were the signs of lacking of confidence. However, the next cycle was in general a success. The students' questions increased considerably. They looked more enthusiastic, passionate and happier in response to teachers' invitation to inquire, showing that their self-confidence for asking questions has developed. 展开更多
关键词 self-confidence RESPECT ENCOURAGEMENT
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Students' Satisfaction with Simulation Learning Environment in Relation to Self-confidence and Learning Achievement
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作者 Abdulaziz Saleh Aljohanil Qayomi Karim Pachev George 《Journal of Health Science》 2016年第5期228-235,共8页
The evolution in patient simulation as educational tool is being driven by a number of factors. Priority of patient safety, patient availability, and the ever increasing body of medical knowledge presents new challeng... The evolution in patient simulation as educational tool is being driven by a number of factors. Priority of patient safety, patient availability, and the ever increasing body of medical knowledge presents new challenges to curriculum planners. Student's satisfaction is an important element of the investigation of simulation learning environment efficacy. There are suggestions that student satisfaction may have some correlation with self-confidence and learning achievement. This is a prospective exploratory study that evaluates learners' satisfaction with simulation learning environment and self-conference utilized satisfaction with SSE (simulation experience scale) and pre and post simulation test for learning achievement. Participants was third-year medical students (n = 45) participating in their regular simulation-based session at Center of Excellence for Simulation Education and Innovation (CESEI), University of British Columbia. A comparison between pre- and post-test results was conducted on the basis of t-test for related samples. Correlation was used to explore the relationships among students satisfaction with the simulation environment and students' self-confidence and achievement. The simulation exercise, completed by 45 students, increased correct test answers on average from 72% to 89% (P-Value 〈 0.0001 by paired t-test). Increases in test results were between pre- and post- simulation identical multiple choice questions. The mean score for satisfaction with simulation environment items was 4.47, SD (0.45), using a 5-point Likert scale with 5 = strongly agree, 4 = agree, 3 = neutral, 2 = disagree, and 1 = strongly disagree. The mean score for self-confidence in performing BLS, evaluating and managing acute cardiac patient was 3.83, SD (1.02). For evaluating the relationship between students satisfaction with simulation learning environment and learning achievement, bivariate analysis revealed a significant positive relationship between satisfaction with simulation learning environment and learning achievement (Pearson r = 0.80, P-Value 〈 0.01). The magnitude or strength of the correlation coefficient (r = 0.80) indicated satisfaction with simulation environment and learning achievement have a strong effect and positive correlation. Simulation learning environment for medical students is effective in improving students' overall comprehension and better learning achievements. Furthermore, students' basic clinical skills are improved associated with higher self-confidence. 展开更多
关键词 SIMULATION self-confidence learning achievement.
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Culture Crisis and Culture Self-confidence
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作者 QIAO Zhao-hong 《Cultural and Religious Studies》 2017年第8期493-497,共5页
The cultural crisis is an inevitable process for any nation and country in the process of modernization. But the crisis is not terrible. With the cultural conflict, it contributes to integration and regeneration. Ther... The cultural crisis is an inevitable process for any nation and country in the process of modernization. But the crisis is not terrible. With the cultural conflict, it contributes to integration and regeneration. Therefore, when Western learning spread to the East, which means the tradition turns to the modernization, the Eastern learning also spreaded to the West, which means using traditional approaches to solve the problems of modernization. The key to this problem is to construct a new cultural value system that meets the needs of modernization and the future society in the clash and crisis of culture. Chinese should be more confident in meeting foreign culture nowadays. There is no need to be afraid of the mingling of gold and sand, let alone the loss of national unique quality. In an era of reconstruction of the world order, China needs a globalized cultural narrative to rebuild the position of China and Asia in the world's cultural history and retrieve the lost position of Chinese culture. To this end, we can learn from nutrients of history and culture, establish self-confidence. 展开更多
关键词 traditional culture INHERIT TRANSCENDENCE cultural awareness cultural self-confidence
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CHINA'S SELF-CONFIDENCE AND CONSCIOUSNESS IN GLOBAL GOVERNANCE
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作者 WANG YIWEI 《Contemporary World》 2017年第1期30-33,共4页
'China should make greater contributions to mankind.'Such contributions are now to be found more and more on the level of global governance.As General Secretary Xi Jinping observed in his New Year Address of 2... 'China should make greater contributions to mankind.'Such contributions are now to be found more and more on the level of global governance.As General Secretary Xi Jinping observed in his New Year Address of 2016,'the world is too big,and challenges are too many,to go without the voice from China being heard,without solution ideas from China being shared,without the involvement of China being needed'. 展开更多
关键词 CHINA’S self-confidence AND CONSCIOUSNESS IN GLOBAL GOVERNANCE CPC BUILDER MORE
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Water, Sanitation and Hygiene in Lower-Level Health Care Facilities of Dar es Salaam Region in Tanzania: Status towards Achieving the Sustainable Development Goals and Way Forward
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作者 Mariam Mahamudu Hussein Mohamed +8 位作者 Michael Habtu Dennis Rweyemamu Anyitike Mwakitalima Amour Seleman Erick Mgina Khalid Massa Grace Saguti Andre Arsene Bita Fouda Zabulon Yoti 《Advances in Infectious Diseases》 CAS 2024年第1期279-295,共17页
Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) ... Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) has set a target for each United Nations member state to reach by 2030. Each member state is required to reach by 2022, 2025 and 2030 at least 60%, 80% and 100%, respectively of basic level of service of the five elements which are water, sanitation, hygiene, waste management and environmental cleaning. Methods: This study aimed to evaluate and document the current state of basic water, sanitation, and hygiene services in all lower-level health care facilities in the Dar es Salaam region of Tanzania as of July 2022. A cross-sectional study was conducted in 99 public dispensaries in the Dar es Salaam region’s five councils: Ubungo, Kigamboni, Kinondoni and Temeke Municipalities, and Ilala City. The interviewee form and observational checklists were both digitalized using the Kobo tool software. The respondents were health care facility in-charges or nurse in-charges. Data were downloaded, validated, and imported to Stata version 15 for analysis. Results: The basic WASH level per JMP is far below the target in 2022. Each member state by 2022 is required to reach at least 60% of the basic level of service of each element. We found a low coverage of basic WASH in the 99 dispensaries included in this study. The basic WASH coverage was met in only 10 (10.1%) of the dispensaries, while the remaining 89 (89.9%) dispensaries fall on limited WASH services. Conclusion: This study revealed lower coverage of basic WASH services in dispensaries. An urgent need is required to improve the status of WASH in all the dispensaries and facilitate the provision of quality health care services, patient safety and reduce health care associated infections. 展开更多
关键词 Dispensaries Low level Health Care Facilities Service levels Basic WASH Dar es Salaam
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Analysis of level structure and monopole effects in Ca isotopes
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作者 Jin Li Ai-Xi Chen +1 位作者 Amir Jalili Han-Kui Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期161-167,共7页
Understanding the properties of nuclei near the double magic nucleus^(40)Ca is crucial for both nuclear theory and experiments.In this study,Ca isotopes were investigated using an extended pairing-plus-quadrupole mode... Understanding the properties of nuclei near the double magic nucleus^(40)Ca is crucial for both nuclear theory and experiments.In this study,Ca isotopes were investigated using an extended pairing-plus-quadrupole model with monopole corrections.The negative-parity states of^(44)Ca were coupled with the intruder orbital g_(9/2)at 4 MeV.The values of E_(4+)/E_(2+)agree well with experimental trend from^(42)Ca to^(50)Ca,considering monopole effects between νf_(7/2)and νp_(3/2)(νf_(5/2)).This monopole effect,determined from data of^(48)Ca and^(50)Ca,supports the proposed new nuclear magic number N=34 by predicting a high-energy 2^(+)state in^(54)Ca. 展开更多
关键词 Shell model Doubly magic ISOTOPES Monopole effects level structure
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Dynamics of information diffusion and disease transmission in time-varying multiplex networks with asymmetric activity levels
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作者 谢笑笑 霍良安 +1 位作者 董雅芳 程英英 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期690-699,共10页
While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network evolution.In this study,we construct a new two-layer ... While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network evolution.In this study,we construct a new two-layer coupling model to explore the interactions between information and disease.The upper layer describes the diffusion of disease-related information,and the lower layer represents the disease transmission.We then use power-law distributions to examine the influence of asymmetric activity levels on dynamic propagation,revealing a mapping relationship characterizing the interconnected propagation of information and diseases among partial nodes within the network.Subsequently,we derive the disease outbreak threshold by using the microscopic Markov-chain approach(MMCA).Finally,we perform extensive Monte Carlo(MC)numerical simulations to verify the accuracy of our theoretical results.Our findings indicate that the activity levels of individuals in the disease transmission layer have a more significant influence on disease transmission compared with the individual activity levels in the information diffusion layer.Moreover,reducing the damping factor can delay disease outbreaks and suppress disease transmission,while improving individual quarantine measures can contribute positively to disease control.This study provides valuable insights into policymakers for developing outbreak prevention and control strategies. 展开更多
关键词 information diffusion disease transmission asymmetric activity levels quarantine strength
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Monitoring absolute vertical land motions and absolute sea-level changes from GPS and tide gauges data over French Polynesia
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作者 Xianjie Li Jean-Pierre Barriot +2 位作者 Bernard Ducarme Marania Hopuare Yidong Lou 《Geodesy and Geodynamics》 EI CSCD 2024年第1期13-26,共14页
In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as an... In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as ancillary results,estimates of the absolute changes in sea level at the same locations.To verify our processing approach to determining vertical motion,we first modeled vertical motion at the International GNSS Service(IGS)THTI station located in the capital island of Tahiti and compared our estimate with previous independent determinations,with a good agreement.We obtained the following estimates for the vertical land motions at the tide gauges:Tubuai island,Austral Archipelago-0.92±0.17 mm/yr,Vairao village,Tahiti Iti:-0.49±0.39 mm/yr,Rikitea,Gambier Archipelago-0.43±0.17 mm/yr.The absolute variations of the sea level are:Tubuai island,Austral Archipelago 5.25±0.60 mm/yr,Vairao village,Tahiti Iti:3.62±0.52 mm/yr,Rikitea,Gambier Archipelago 1.52±0.23 mm/yr.We discuss these absolute values in light of the values obtained from altimetric measurements and other means in French Polynesia. 展开更多
关键词 GPS Tide gauges Sea level changes Vertical land motion
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Dynamic characteristics of coal specimens with varying static preloading levels under low-frequency disturbance load
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作者 WEN Xiao-ze FENG Guo-rui +5 位作者 GUO Jun YU Lu-yang QIAN Rui-peng ZHANG Jie ZHANG Peng-fei FENG Wen-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2644-2657,共14页
The mechanical properties of residual coal pillars under the influence of upward mining disturbances significantly affect the safety of residual mining activities on working faces.This study conducted low-frequency di... The mechanical properties of residual coal pillars under the influence of upward mining disturbances significantly affect the safety of residual mining activities on working faces.This study conducted low-frequency disturbance dynamic uniaxial compression tests on coal specimens using a self-developed dynamic-static load coupling electro-hydraulic servo system,and studied the strength evolutions,surface deformations,acoustic emission(AE)characteristic parameters,and the failure modes of coal specimens with different static preloading levels were studied.The disturbance damage is positively correlated with the coal specimen static preload level.Specifically,the cumulative AE count rates of the initial accelerated damage stage for the coal specimens with static preloading level of 60%and 70%of the uniaxial compressive strength(UCS)were 2.66 and 3.19 times that of the 50%UCS specimens,respectively.Macroscopically,this behaviour manifested as a decrease in the compressive strength,and the mean strengths of the disturbance-damaged coal specimens with 60%and 70%of UCS static preloading decreased by 8.53%and 9.32%,respectively,compared to those of the specimens under pure static loading.The crack sources,such as the primary fissures,strongly control the dynamic response of the coal specimen.The difference between the dynamic responses of the coal specimens and that of dense rocks is significant. 展开更多
关键词 low-frequency disturbance dynamic response coal specimens static preloading level
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Source and level of dietary iron influence semen quality by affecting inflammation, oxidative stress and iron utilization levels in boars
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作者 Yinghui Wu Yamei Li +8 位作者 Yueyue Miao Hongkui Wei Hefeng Luo Chunxiao Ren Yawei Zhang Juan Chen Tanghong Wei Jiyan Deng Jian Peng 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2044-2058,共15页
Background Boars fed a mixed form of inorganic and organic iron in excess of the NRC recommended levels still develop anemia,which suggested that the current level and form of iron supplementation in boar diets may be... Background Boars fed a mixed form of inorganic and organic iron in excess of the NRC recommended levels still develop anemia,which suggested that the current level and form of iron supplementation in boar diets may be inappropriate.Therefore,56 healthy Topeka E line boars aged 15–21 months were randomly divided into 5 groups:basal diet supplemented with 96 mg/kg ferrous sulfate(FeSO_(4))and 54 mg/kg glycine chelated iron(Gly-Fe,control);80 mg/kg or 115 mg/kg Gly-Fe;80 mg/kg or 115 mg/kg methionine hydroxyl analogue chelated iron(MHA-Fe,from CalimetFe)for 16 weeks.The effects of dietary iron supplementation with different sources and levels on semen quality in boars were investigated.Results 1)Serum Fe and hemoglobin concentrations were not affected by reduced dietary iron levels in the 80 mg/kg or 115 mg/kg Gly-Fe and MHA-Fe groups compared with the control group(P>0.05).2)Serum interleukin-6(IL-6)and sperm malondialdehyde(MDA)levels in the 80 mg/kg or 115 mg/kg MHA-Fe groups were lower than those in the control group(P<0.05),and higher serum superoxide dismutase levels and lower MDA levels in the 115 mg/kg MHA-Fe group(P<0.05).3)Boars in the 80 mg/kg or 115 mg/kg Gly-Fe and MHA-Fe groups had lower serum hepcidin(P<0.01),ferritin(P<0.05),and transferrin receptor(P<0.01)concentrations,and boars in the 115 mg/kg MHA-Fe group had higher seminal plasma Fe concentrations compared with the control group.4)Boars in the 80 mg/kg and 115 mg/kg MHA-Fe groups had lower abnormal sperm rate and in situ oscillating sperm ratio compared to the control group at weeks 12 and/or 16 of the trial.However,the effect of Gly-Fe on improving semen quality in boars was not evident.5)Serum IL-6 level was positively correlated with hepcidin concentration(P<0.05),which in turn was significantly positively correlated with abnormal sperm rate(P<0.05).Furthermore,significant correlations were also found between indicators of iron status and oxidative stress and semen quality parameters.Conclusions Dietary supplementation with 80 mg/kg or 115 mg/kg MHA-Fe did not induce iron deficiency,but rather reduced serum inflammatory levels and hepcidin concentration,alleviated oxidative stress,increased body iron utilization,and improved semen quality in adult boars. 展开更多
关键词 Adult boars Iron level Iron source Iron status Semen quality
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Methodology for local correction of the heights of global geoid models to improve the accuracy of GNSS leveling
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作者 Stepan Savchuk Alina Fedorchuk 《Geodesy and Geodynamics》 EI CSCD 2024年第1期42-49,共8页
At present,one of the methods used to determine the height of points on the Earth’s surface is Global Navigation Satellite System(GNSS)leveling.It is possible to determine the orthometric or normal height by this met... At present,one of the methods used to determine the height of points on the Earth’s surface is Global Navigation Satellite System(GNSS)leveling.It is possible to determine the orthometric or normal height by this method only if there is a geoid or quasi-geoid height model available.This paper proposes the methodology for local correction of the heights of high-order global geoid models such as EGM08,EIGEN-6C4,GECO,and XGM2019e_2159.This methodology was tested in different areas of the research field,covering various relief forms.The dependence of the change in corrected height accuracy on the input data was analyzed,and the correction was also conducted for model heights in three tidal systems:"tide free","mean tide",and"zero tide".The results show that the heights of EIGEN-6C4 model can be corrected with an accuracy of up to 1 cm for flat and foothill terrains with the dimensionality of 1°×1°,2°×2°,and 3°×3°.The EGM08 model presents an almost identical result.The EIGEN-6C4 model is best suited for mountainous relief and provides an accuracy of 1.5 cm on the 1°×1°area.The height correction accuracy of GECO and XGM2019e_2159 models is slightly poor,which has fuzziness in terms of numerical fluctuation. 展开更多
关键词 GNSS leveling Global geoid model Gravity anomaly Weight data Correcting data
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Antibody Levels and Infection Status of Pertussis in the Population under Pertussis Resurgence in Guangxi in 2018:A Cross-Sectional Survey
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作者 Liang Liang Qiuyun Deng +6 位作者 Lili Deng Jinghang Wei Shiyi Chen Yizhi Wei Yuyan Ma Yue Qin Wei Liu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第6期628-638,共11页
Objective Pertussis cases have increased markedly since 2018 in Guangxi.The aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident population.Method A total of 10,215 s... Objective Pertussis cases have increased markedly since 2018 in Guangxi.The aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident population.Method A total of 10,215 serum samples from residents were collected from August-November 2018 and tested for anti-pertussis IgG and toxin IgG using the enzyme-linked immunosorbent assay(ELISA).Results Of the collected samples,1,833(17.94%)tested positive for anti-pertussis IgG,with the median concentration of 16.06 IU/mL.Antibody level<10 IU/mL accounted for more than 60%in children under 4 years of age,but declined with age,whereas the percentages of the other three levels(10-40,40-50,and≥50 IU/mL)increased almost with age(P<0.001).Moreover,7,924 samples were selected for anti-pertussis toxin IgG,of which 653(8.24%)tested positive(≥40 IU/mL)with the median concentration of 5.89 IU/mL,and 204 participants(2.56%)had recent pertussis infection(≥100 IU/mL).Among the different age groups,the highest rates of positivity and recent infection were observed at 11-20 years of age,the lowest positivity rate at 5 years of age,and the lowest recent infection rate at 4 years of age(P<0.001,P=0.005,respectively).Conclusion The survey results showed that all age groups in Guangxi lacked immunity against pertussis,which was one of the main factors contributing to the resurgence of pertussis in 2018.In addition,the prevalence of pertussis is relatively high in Guangxi,and its incidence is seriously underestimated,especially in adolescents and adults. 展开更多
关键词 Pertussis resurgence Anti-pertussis IgG Anti-pertussis toxin IgG Antibody level Infection status
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The real-time dynamic liquid level calculation method of the sucker rod well based on multi-view features fusion
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作者 Cheng-Zhe Yin Kai Zhang +4 位作者 Jia-Yuan Liu Xin-Yan Wang Min Li Li-Ming Zhang Wen-Sheng Zhou 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3575-3586,共12页
In the production of the sucker rod well, the dynamic liquid level is important for the production efficiency and safety in the lifting process. It is influenced by multi-source data which need to be combined for the ... In the production of the sucker rod well, the dynamic liquid level is important for the production efficiency and safety in the lifting process. It is influenced by multi-source data which need to be combined for the dynamic liquid level real-time calculation. In this paper, the multi-source data are regarded as the different views including the load of the sucker rod and liquid in the wellbore, the image of the dynamometer card and production dynamics parameters. These views can be fused by the multi-branch neural network with special fusion layer. With this method, the features of different views can be extracted by considering the difference of the modality and physical meaning between them. Then, the extraction results which are selected by multinomial sampling can be the input of the fusion layer.During the fusion process, the availability under different views determines whether the views are fused in the fusion layer or not. In this way, not only the correlation between the views can be considered, but also the missing data can be processed automatically. The results have shown that the load and production features fusion(the method proposed in this paper) performs best with the lowest mean absolute error(MAE) 39.63 m, followed by the features concatenation with MAE 42.47 m. They both performed better than only a single view and the lower MAE of the features fusion indicates that its generalization ability is stronger. In contrast, the image feature as a single view contributes little to the accuracy improvement after fused with other views with the highest MAE. When there is data missing in some view, compared with the features concatenation, the multi-view features fusion will not result in the unavailability of a large number of samples. When the missing rate is 10%, 30%, 50% and 80%, the method proposed in this paper can reduce MAE by 5.8, 7, 9.3 and 20.3 m respectively. In general, the multi-view features fusion method proposed in this paper can improve the accuracy obviously and process the missing data effectively, which helps provide technical support for real-time monitoring of the dynamic liquid level in oil fields. 展开更多
关键词 Dynamic liquid level Multi view Features fusion Sucker rod well Dynamometer cards
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基于ε-level蝙蝠算法的无人机三维航迹规划 被引量:3
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作者 王福仪 孟秀云 张海阔 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第5期1593-1603,共11页
针对复杂地形环境、存在各种威胁和约束的无人机航迹规划问题,提出了一种基于ε-level改进蝙蝠算法的航迹规划算法。根据无人机目标函数和约束条件,建立无人机三维航迹规划模型;其次,针对蝙蝠算法处理高维带约束问题存在的早熟现象,设... 针对复杂地形环境、存在各种威胁和约束的无人机航迹规划问题,提出了一种基于ε-level改进蝙蝠算法的航迹规划算法。根据无人机目标函数和约束条件,建立无人机三维航迹规划模型;其次,针对蝙蝠算法处理高维带约束问题存在的早熟现象,设计了自适应权重系数和迭代阈值以平衡算法的探索能力和开发能力,并结合ε-level比较策略提高算法对非凸非线性约束优化问题的处理能力;设计了转弯半径可变的Dubins曲线用来对航迹进行平滑处理并解决2个航迹点连线贯穿地形的问题。通过仿真实验,并与蝙蝠算法、粒子群优化算法、ε-level粒子群优化算法和ε-level差分进化算法相比较,所提算法在开发能力、稳定性和成功率等方面都表现出较优的性能。 展开更多
关键词 无人机航迹规划 蝙蝠算法 自适应权重系数 ε-level比较策略 Dubins平滑
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Sediment Dynamics Subject to Sea Level Rise in the Yangtze River Estuary
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作者 CHEN Wei BAN Haoyang +2 位作者 MAO Chenhao LIANG Huidi JIANG Mingtao 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第6期1572-1582,共11页
In this study,a two-dimensional hydrodynamic and sediment transport model is established to quantify the influences of sea level rise on sediment transport in the Yangtze River Estuary(YRE).After validation,the model ... In this study,a two-dimensional hydrodynamic and sediment transport model is established to quantify the influences of sea level rise on sediment transport in the Yangtze River Estuary(YRE).After validation,the model was employed to investigate the sediment transport and seabed evolution under four different scenarios of sea level rise,specifically,0,0.5,1 and 1.5 m.The results reveal that there exists a‘transition point(TP)'of SSC in each main channel of YRE.Upstream of the transition point,the suspended sediment concentration(SSC)increases along with the rise in sea level,while downstream of the transition point,SSC decreases as sea level rises.Similarly,there are also transition points for topography evolution.The maximum scouring rate upstream of the transition points exceeds 4.32% for a 1.5 m rise in sea level,while the maximum deposition rate downstream of the transition points is 2.48%.The sediment fluxes from upstream to downstream in the branches of YRE are enhanced by the rise in sea level.The direction of sediment flux in the North Branch reverses downstream as sea level rises.The sediment flux from the North Channel towards downstream increases significantly,while there is no significant change in sediment flux for South Channel.Sediment deposition in the North Passage is also accelerated by sea level rise.In addition,the sediment flux from YRE to northern Jiangsu and Hangzhou Bay is also weakened by the rise in sea level. 展开更多
关键词 sea level rise sediment transport erosion and deposition sediment flux
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