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On Foreground-Background and Transitivity in Chinese Shiwu(事物) Expository Discourse 被引量:2
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作者 XU Ai-gai 《Journal of Literature and Art Studies》 2019年第11期1180-1187,共8页
Foreground-background and transitivity are very important in discourse linguistics,the features of which vary from types of discourse.Chinese shiwu expository discourse has its own semantic features about foreground-b... Foreground-background and transitivity are very important in discourse linguistics,the features of which vary from types of discourse.Chinese shiwu expository discourse has its own semantic features about foreground-background;and this type of discourse is characterized by low transitivity,especially in foreground. 展开更多
关键词 CHINESE shiwu expository DISCOURSE Explanatory object foreground background Low TRANSITIVITY
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A Nonparametric Approach to Foreground Detection in Dynamic Backgrounds 被引量:3
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作者 LIAO Juan JIANG Dengbiao +2 位作者 LI Bo RUAN Yaduan CHEN Qimei 《China Communications》 SCIE CSCD 2015年第2期32-39,共8页
Foreground detection is a fundamental step in visual surveillance.However,accurate foreground detection is still a challenging task especially in dynamic backgrounds.In this paper,we present a nonparametric approach t... Foreground detection is a fundamental step in visual surveillance.However,accurate foreground detection is still a challenging task especially in dynamic backgrounds.In this paper,we present a nonparametric approach to foreground detection in dynamic backgrounds.It uses a history of recently pixel values to estimate background model.Besides,the adaptive threshold and spatial coherence are introduced to enhance robustness against false detections.Experimental results indicate that our approach achieves better performance in dynamic backgrounds compared with several approaches. 展开更多
关键词 foreground detection dynamic background the decision threshold spatial coherence
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Foregrounding Features in the Background Introduction Partin Oliver Twist
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作者 刘婷 《海外英语》 2019年第12期206-207,共2页
The theory of foregrounding is a theory of crucial and critical importance in Stylistics.In stylistic analysis,foregrounding refers to the work with literary and artistic importance,especially the deviation of languag... The theory of foregrounding is a theory of crucial and critical importance in Stylistics.In stylistic analysis,foregrounding refers to the work with literary and artistic importance,especially the deviation of language,prominent in the background which belongs to the normal conventions of language.Charles Dickens is one of the greatest and critical realist writers of the Victorian Age in British.In his representative work Oliver Twist,by the bitter exposure of the terrible conditions in the English workhouse of the time and the cruel treatment of a poor orphan by all sorts of philanthropist,the author criticizes harshly the dark and criminal underworld life and succeeds in calling forth the reader's sympathy for the down-trodden people of the lower classes,especially the children.Through his master skill of the use of foregrounding,Dickens constructs various kinds of background introductions where is full of suspense and symbol,and it seems that all the backgrounds are inseparably closed to the fate of the protagonist,leaving a clue for the reader to pick out the main idea of the total work.This thesis firstly reviews the theory of foregrounding and then analyses the foregrounding using in the background introductions in Oliver Twist,presenting a holistic overview the aim of the author and what he aims at expressing through the intended background description. 展开更多
关键词 Oliver TWIST foregroundING background DESCRIPTION
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The Lateral Occipital Complex is Activated by Melody with Accompaniment: Foreground and Background Segregation in Auditory Processing
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作者 Masayuki Satoh Katsuhiko Takeda +1 位作者 Ken Nagata Hidekazu Tomimoto 《Journal of Behavioral and Brain Science》 2011年第3期94-101,共8页
Objective: Most of the western music consists of a melody and an accompaniment. The melody is referred to as the foreground, with the accompaniment the background. In visual processing, the lateral occipital complex (... Objective: Most of the western music consists of a melody and an accompaniment. The melody is referred to as the foreground, with the accompaniment the background. In visual processing, the lateral occipital complex (LOC) is known to participate in foreground and background segregation. We investigated the role of LOC in music processing with use of positron emission tomography (PET). Method: Musically na?ve subjects listened to unfamiliar novel melodies with (accompaniment condition) and without the accompaniment (melodic condition). Using a PET subtraction technique, we studied changes in regional cerebral blood flow (rCBF) during the accompaniment condition compared to the melodic condition. Results: The accompanyment condition was associated with bilateral increase of rCBF at the lateral and medial surfaces of both occipital lobes, medial parts of fusiform gyri, cingulate gyri, precentral gyri, insular cortices, and cerebellum. During the melodic condition, the activation at the anterior and posterior portions of the temporal lobes, medial surface of the frontal lobes, inferior frontal gyri, orbitofrontal cortices, inferior parietal lobules, and cerebellum was observed. Conclusions: The LOC participates in recognition of melody with accompaniment, a phenomenon that can be regarded as foreground and background segregation in auditory processing. The fusiform cortex which was known to participate in the color recognition might be activated by the recognition of flourish sounds by the accompaniment, compared to melodic condition. It is supposed that the LOC and fusiform cortex play similar functions beyond the difference of sensory modalities. 展开更多
关键词 Music Positron Emission Tomography (PET) MELODY ACCOMPANIMENT foreground and background SEGREGATION Lateral OCCIPITAL Complex (LOC)
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The collaborative cross mouse for studying the effect of host genetic background on memory impairments due to obesity and diabetes 被引量:1
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作者 Avia Paz Kareem Midlej +2 位作者 Osayd Zohud Iqbal MLone Fuad A.Iraqi 《Animal Models and Experimental Medicine》 2025年第1期126-141,共16页
Background:Over the past few decades,a threefold increase in obesity and type 2 diabetes(T2D)has placed a heavy burden on the health-care system and society.Previous studies have shown correlations between obesity,T2D... Background:Over the past few decades,a threefold increase in obesity and type 2 diabetes(T2D)has placed a heavy burden on the health-care system and society.Previous studies have shown correlations between obesity,T2D,and neurodegenera-tive diseases,including dementia.It is imperative to further understand the relation-ship between obesity,T2D,and cognitive deficits.Methods:This investigation tested and evaluated the cognitive impact of obesity and T2D induced by high-fat diet(HFD)and the effect of the host genetic background on the severity of cognitive decline caused by obesity and T2D in collaborative cross(CC)mice.The CC mice are a genetically diverse panel derived from eight inbred strains.Results:Our findings demonstrated significant variations in the recorded phenotypes across different CC lines compared to the reference mouse line,C57BL/6J.CC037 line exhibited a substantial increase in body weight on HFD,whereas line CC005 ex-hibited differing responses based on sex.Glucose tolerance tests revealed significant variations,with some lines like CC005 showing a marked increase in area under the curve(AUC)values on HFD.Organ weights,including brain,spleen,liver,and kidney,varied significantly among the lines and sexes in response to HFD.Behavioral tests using the Morris water maze indicated that cognitive performance was differentially affected by diet and genetic background.Conclusions:Our study establishes a foundation for future quantitative trait loci map-ping using CC lines and identifying genes underlying the comorbidity of Alzheimer's disease(AD),caused by obesity and T2D.The genetic components may offer new tools for early prediction and prevention. 展开更多
关键词 collaborative cross mouse DIABETES host genetic background memory impairments OBESITY
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Construction and characteristic analysis of background error covariance coupled with land surface temperature 被引量:1
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作者 Qihang Yang Yaodeng Chen +4 位作者 Luyao Qin Yuanbing Wang Deming Meng Xusheng Yan Xinyao Qian 《Atmospheric and Oceanic Science Letters》 2025年第3期7-12,共6页
Land surface temperature(LST)is the key variable in land-atmosphere interaction,having an important impact on weather and climate forecasting.However,achieving consistent analysis of LST and the atmosphere in assimila... Land surface temperature(LST)is the key variable in land-atmosphere interaction,having an important impact on weather and climate forecasting.However,achieving consistent analysis of LST and the atmosphere in assimilation is quite challenging.This is because there is limited knowledge about the cross-component background error covariance(BEC)between LST and atmospheric state variables.This study aims to clarify whether there is a relationship between the error of LST and atmospheric variables,and whether this relationship varies spatially and temporally.To this end,the BEC coupled with atmospheric variables and LST was constructed(LST-BEC),and its characteristics were analyzed based on the 2023 mei-yu season.The general characteristics of LST-BEC show that the LST is mainly correlated with the atmospheric temperature and the correlation decreases gradually with a rise in atmospheric height,and the error standard deviation of the LST is noticeably larger than that of the low-level atmospheric temperature.The spatiotemporal characteristics of LST-BEC on the heavy-rain day and light-rain day show that the error correlation and error standard deviation of LST and low-level atmospheric temperature and humidity are closely related to the weather background,and also have obvious diurnal variations.These results provide valuable information for strongly coupled land-atmosphere assimilation. 展开更多
关键词 background error covariance Land surface temperature Error correlation Error standard deviation Data assimilation
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Association of the glycemic background patterns and the diabetes management efficacy in poorly controlled type 2 diabetes
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作者 Ayşe N Erbakan Müzeyyen Arslan Bahadır +6 位作者 FatoşN Kaya Büşra Güleç MiraçVural Keskinler Ümmügülsüm AktemurÇelik Özge Faydalıel Banu Mesçi Aytekin Oğuz 《World Journal of Diabetes》 SCIE 2025年第1期74-90,共17页
BACKGROUND Inadequate glycemic control in patients with type 2 diabetes(T2DM)is a major public health problem and a significant risk factor for the progression of diabetic complications.AIM To evaluate the effects of ... BACKGROUND Inadequate glycemic control in patients with type 2 diabetes(T2DM)is a major public health problem and a significant risk factor for the progression of diabetic complications.AIM To evaluate the effects of intensive and supportive glycemic management strategies over a 12-month period in individuals with T2DM with glycated hemoglobin(HbA1c)≥10%and varying backgrounds of glycemic control.METHODS This prospective observational study investigated glycemic control in patients with poorly controlled T2DM over 12 months.Participants were categorized into four groups based on prior glycemic history:Newly diagnosed,previously well controlled with recent worsening,previously off-target but now worsening,and HbA1c consistently above 10%.HbA1c levels were monitored quarterly,and patients received medical,educational,and dietary support as needed.The analysis focused on the success rates of good glycemic control and the associated factors within each group.RESULTS The study showed significant improvements in HbA1c levels in all participants.The most significant improvement was observed in individuals newly diagnosed with diabetes:65%achieved an HbA1c target of≤7%.The results varied between participants with different glycemic control histories,followed by decreasing success rates:39%in participants with previously good glycemic control,21%in participants whose glycemic control had deteriorated compared to before,and only 10%in participants with persistently poor control,with mean HbA1c levels of 6.3%,7.7%,8.2%,and 9.7%,respectively.After one year,65.2%of the“newly diagnosed patients”,39.3%in the“previously controlled group”,21.9%in the“previously off-target but now worsened'”group and 10%in the“poorly controlled from the start”group had achieved HbA1c levels of 7 and below.CONCLUSION In poorly controlled diabetes,the rate at which treatment goals are achieved is associated with the glycemic background characteristics,emphasizing the need for tailored strategies.Therefore,different and comprehensive treatment approaches are needed for patients with persistent uncontrolled diabetes. 展开更多
关键词 Type 2 diabetes mellitus Glycated hemoglobin Glycemic control Patient-centered care Diabetes management glycemic background
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Comparison of Simulated Backgrounds with In-orbit Observations for HXI Onboard ASO-S
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作者 Hao-Xiang Wang Zhe Zhang +4 位作者 Wei Liu Xian-Kai Jiang Deng-Yi Chen Yi-Ming Hu Yang Su 《Research in Astronomy and Astrophysics》 2025年第3期141-153,共13页
The Hard X-ray Imager(HXI)payload,a component of China’s Advanced Space-based Solar Observatory satellite,is designed to observe solar X-ray emissions in the 30-200 keV range,with the aim of investigating nonthermal ... The Hard X-ray Imager(HXI)payload,a component of China’s Advanced Space-based Solar Observatory satellite,is designed to observe solar X-ray emissions in the 30-200 keV range,with the aim of investigating nonthermal physical processes during solar flares.Before launch,Geant4 simulations were employed to assess the onorbit background of the HXI instrument,evaluating its performance and potential to achieve its scientific objectives.This study addresses issues identified in previous simulations and conducts further analyses to examine the distribution of background counts across the 99 detectors.The results demonstrate alignment between simulations and observations at low and medium geomagnetic latitudes;however,challenges persist at high geomagnetic latitudes due to limitations in the current albedo photon model.This investigation provides insights into background sources from various particles,enhances understanding of space background characteristics,and offers guidance for background subtraction in imaging processes. 展开更多
关键词 instrumentation detectors-Sun X-rays gamma-rays-(cosmology )cosmic background radiation-gamma-rays diffuse background
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Study on the Correction Method of Radiant Temperature Measurement of Turbine Blades Under the Background of High-Temperature Dynamics
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作者 Shengnan Liu Liwei Chen 《Instrumentation》 2025年第2期80-90,共11页
The turbine blades operate under high temperature and high pressure conditions,and when using radiation thermometry,the influence of radiation from surrounding blades leads to measurement errors.To address this issue,... The turbine blades operate under high temperature and high pressure conditions,and when using radiation thermometry,the influence of radiation from surrounding blades leads to measurement errors.To address this issue,this paper develops a three-dimensional discretized dynamic radiation transfer model based on the blade shape of the turbine.The relationship between the radiation angle coefficient of the surrounding blades and the rotation angle of the blade under test is analyzed.The radiation angle coefficient is calculated using the triangular element method,and temperature inversion is performed based on the effective emissivity to compute the measurement error.The results show that under dynamic high temperature conditions,the temperature measurement error caused by reflection at the selected 60%leaf height point varies with the rotation angle,and the maximum reaches 25.58K.The angular coefficient exhibits periodic fluctuations with changes in rotation angle,and the maximum effective emissivity increases as the rotation angle increases.As the blade height increases,the impact of reflected radiation on radiometric temperature measurement errors shows a decreasing trend.This study provides a reference for radiation thermometry in dynamic high-temperature environments. 展开更多
关键词 radiation temperature measurement dynamic background turbine blades effective emissivity ERROR
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Enhanced suppression of background in capture reaction measurements with LAMBDA-Ⅱin ground laboratories
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作者 Lu-Yang Song Lin Wang +22 位作者 Jun Su Li-Yong Zhang Jian-Jun He Shi-Lun Jin Fei Lu Yang-Ping Shen Jun-Feng Chen Yao-De Sheng Xin Chen Shen Lin Zhi-Wei Qin Zi-Ming Li Hao Zhang Luo-Huan Wang Yin-Ji Chen Xin-Zhi Jiang Zhi-Lin Shen Xin-Yue Li Feng-Cheng Liu Yi-Tong Huang Si-Ze Chen Bing Guo Wei-Ping Liu 《Nuclear Science and Techniques》 2025年第11期273-282,共10页
The precise determination of cross sections for key nuclear reactions within the Gamow window is crucial for advancing the study of stellar evolution and nucleosynthesis.However,extremely low reaction yields combined ... The precise determination of cross sections for key nuclear reactions within the Gamow window is crucial for advancing the study of stellar evolution and nucleosynthesis.However,extremely low reaction yields combined with the cosmic-ray-induced background make these measurements highly challenging,particularly for capture reactions.This work demonstrates the second configuration of the large-scale modular BGO detection array(LAMBDA-Ⅱ)designed to capture reaction measurements and introduces a method for suppressingγ-ray detection background in ground laboratories.By employing active and passive shielding,the background of LAMBDA-Ⅱwas significantly reduced by approximately two orders of magnitude,reaching 8.1×10^(-3)and 1.0×10^(-3)keV^(-1)h^(-1)in the 6-11 and 11-20 MeV energy ranges,respectively.When combined with a mA-scale intensity beam,this reduced background enables the investigation of several capture reactions of astrophysical interest in ground laboratories. 展开更多
关键词 Nuclear astrophysics Capture reaction background Summing technique γdetector array SHIELDING
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Identification of QTL-by-environment interaction by controlling polygenic background effect
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作者 Fuping Zhao Lixian Wang Shizhong Xu 《Journal of Genetics and Genomics》 2025年第7期915-926,共12页
The quantitative trait loci(QTL)-by-environment(Q × E) interaction effect is hard to detect because there are no effective ways to control the genomic background. In this study, we propose a linear mixed model th... The quantitative trait loci(QTL)-by-environment(Q × E) interaction effect is hard to detect because there are no effective ways to control the genomic background. In this study, we propose a linear mixed model that simultaneously analyzes data from multiple environments to detect Q × E interactions. This model incorporates two different kinship matrices derived from the genome-wide markers to control both main and interaction polygenic background effects. Simulation studies demonstrate that our approach is more powerful than the meta-analysis and inclusive composite interval mapping methods. We further analyze four agronomic traits of rice across four environments. A main effect QTL is identified for 1000-grain weight(KGW), while no QTL are found for tiller number. Additionally, a large QTL with a significant Q × E interaction is detected on chromosome 7 affecting grain number, yield, and KGW. This region harbors two important genes, PROG1 and Ghd7. Furthermore, we apply our mixed model to analyze lodging in barley across six environments. The six regions exhibiting Q × E interaction effects identified by our approach overlap with the SNPs previously identified using EM and MCMC-based Bayesian methods, further validating the robustness of our approach. Both simulation studies and empirical data analyses show that our method outperforms all other methods compared. 展开更多
关键词 Q×E interaction Main effect META-ANALYSIS Mixed model Polygenic background
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A Preliminary Study on the Background of the Formation of the Meng Yao Zheng Dian
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作者 Hongying Wu Bao Long 《Journal of Clinical and Nursing Research》 2025年第2期93-101,共9页
Meng Yao Zheng Dian is one of the three classics of Mongolian medicine.It was written by Zhanbra Dorje,who was a famous Mongolian physician.The book was not only related to the author's origin,education and learni... Meng Yao Zheng Dian is one of the three classics of Mongolian medicine.It was written by Zhanbra Dorje,who was a famous Mongolian physician.The book was not only related to the author's origin,education and learning experience,but also closely related to the social development,cultural exchanges between Mongolian and Tibetan,and people's demand for Mongolian medicine at that time.The book in four languages indicates the name of Mongolian medicinal herbs,Mongolian of China,Tibetan of China,Chinese,Manchu medicine academic and cultural exchanges played a positive role in promoting the cultural exchanges,is a vivid embodiment of the cultural exchanges between Chinese nationalities and exchanges and mingling. 展开更多
关键词 Zhanbra Dorje Meng Yao Zheng Dian background of the book
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Quantifying background PM_(2.5) concentrations in Hainan Province,China through model simulations constrained by multi-source observations
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作者 Yibo Zhang Yanning Zhang +14 位作者 Yuhong Guo Jiming Hao Wenshuai Xu Weijun Yan Shuxiao Wang Qian Song Shengyue Li Weiling Xiang Li Luo Xiaofeng Huang Zhaohui Yang Xiaochen Wu Yun Zhu Shuhan Liu Bin Zhao 《Frontiers of Environmental Science & Engineering》 2025年第12期279-294,共16页
As a national ecological civilization pilot zone with unprecedented strategic importance in China,Hainan Province requires precise identification of PM_(2.5) background concentrations to achieve world-leading air qual... As a national ecological civilization pilot zone with unprecedented strategic importance in China,Hainan Province requires precise identification of PM_(2.5) background concentrations to achieve world-leading air quality objectives.This study utilized the three-dimensional regional air quality modeling(WRF-CMAQ)and integrated multi-source ground observation data for model validation.To quantify the PM_(2.5) background values for Hainan,representing concentrations largely influenced by natural emissions and regional transport,we determined the contributions from these sources.The results identified local anthropogenic emissions(49.5%)and regional transport(29.3%)as the dominant PM_(2.5) sources in Hainan,with important natural contributions(19.0%).Based on the theoretical definition of background concentrations grounded in scientific research and the objective of providing practical policy insights for Hainan,the PM_(2.5) background values were defined as the PM_(2.5) concentration after(1)excluding local anthropogenic emissions;(2)excluding anthropogenic emissions across Hainan and its surrounding regions;and(3)excluding local emissions combined with projected 2035 emission scenarios for surrounding areas.Based on these three definition methods,the 18 cities-averaged PM_(2.5) background values for Hainan were determined as 6.9,4.2,and 5.2μg/m^(3),while the corresponding gridaveraged values calculated were 6.7,4.6,and 4.9μg/m^(3),respectively.Accounting for meteorological fluctuations could yield lower estimated PM_(2.5) concentrations for Hainan.Hainan’s PM_(2.5) background values showed comparability with levels documented in clean island areas globally.Our study demonstrated that Hainan maintained a relatively low PM_(2.5) background level,showing substantial emission reduction potential.Through implementation of effective control measures,Hainan is projected to achieve world-leading air quality by 2035. 展开更多
关键词 background value PM_(2.5)concentration Source contribution Hainan Province CMAQ model
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Interactions of the Background State and Eddies in Shaping Aleutian Low Variations
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作者 Nan LIN Tuantuan ZHANG +3 位作者 Qiaoling REN Ho-Nam CHEUNG Chang-Hoi HO Song YANG 《Advances in Atmospheric Sciences》 2025年第8期1548-1565,共18页
The Aleutian Low(AL)is a dominant feature of the mean circulation in the North Pacific during the winter season.The background stationary wave,air-sea interaction,and transient eddies over the North Pacific exert dist... The Aleutian Low(AL)is a dominant feature of the mean circulation in the North Pacific during the winter season.The background stationary wave,air-sea interaction,and transient eddies over the North Pacific exert distinct impacts on the interannual variations of the AL intensity and position.In this study,we adopt the quasi-geostrophic geopotential tendency equation to investigate the roles of various physical processes in the maintenance and interannual variations of this system.The results show that absolute vorticity advection plays the most important role in the formation and maintenance of AL intensity,while high-frequency transient eddies contribute most to the meridional and zonal shifts of the AL.The high-frequency transient eddy vorticity forcing affects the AL through the barotropic energy conversion process,and,in turn,the AL enhances the high-frequency transient eddies through the baroclinic energy conversion process,forming a positive feedback.The associated high-frequency eddy kinetic energy anomalies exhibit an eastward movement toward the east coast of North America in the years of an intensified AL,which explains why a strengthened AL is often accompanied by an eastward movement.Furthermore,the energy conversion terms of high-frequency transient eddies are mostly located over the extratropical eastern North Pacific,leading to asymmetric features in the zonal movement of the AL. 展开更多
关键词 Aleutian Low interannual variations interactions between eddies and the background flow
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High summer background O_(3)levels in the desert of northwest China
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作者 Xinbing Ren Fang Wang +8 位作者 Bayi Wu Shaoting Zhang Lei Zhang Xingjun Zhou Yuanzhe Ren Yongjing Ma Feng Hao Yongli Tian Jinyuan Xin 《Journal of Environmental Sciences》 2025年第5期516-528,共13页
Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentratio... Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentrations are relatively low.However,high summer background concentrations of about 100μg/m^(3)or 60 ppb were found in the Alxa Desert in the highland of northwest China based on continuous summer observations from 2019 to 2021,which was higher than the most of natural background areas or clean areas in world for summer O_(3)background concentrations.The high O_(3)background concentrations were related to surface features and altitude.Heavy-intensity anthropogenic activity areas in desert areas can cause increased O_(3)concentrations or pollution,but also generated O_(3)depleting substances such as nitrous oxide,which eventually reduced the regional O_(3)baseline values.Nitrogen dioxide(NO2)also had a dual effect on O_(3)generation,showing promotion at low concentrations and inhibition at high concentrations.In addition,sand-dust weather reduced O_(3)clearly,but O_(3)eventually stabilized around the background concentration values and did not vary with sand-dust particulate matter. 展开更多
关键词 Alxa Desert O_(3)background concentration Anthropogenic effect Sand-dust weather Northwest China
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Rogue waves on a periodic background in the reduced Maxwell–Bloch system
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作者 YiJie Zhao Zhaqilao Niqi Ao 《Communications in Theoretical Physics》 2025年第8期25-34,共10页
In this paper,the nonlinearization of the Lax pair and the Darboux transformation method are used to construct the rogue wave on the elliptic function background in the reduced Maxwell–Bloch system,which is described... In this paper,the nonlinearization of the Lax pair and the Darboux transformation method are used to construct the rogue wave on the elliptic function background in the reduced Maxwell–Bloch system,which is described by four component nonlinear evolution equations(NLEEs).On the background of the Jacobian elliptic function,we obtain the admissible eigenvalues and the corresponding non-periodic eigenfunctions of the model spectrum problem.Then,with the help of the one-fold Darboux transformation and two-fold Darboux transformation,rogue waves on a dn-periodic background and cn-periodic background are derived,respectively.Finally,the corresponding complex dynamical properties and evolutions of the four components are illustrated graphically by choosing suitable parameters. 展开更多
关键词 Jacobian elliptic function Darboux transformation reduced Maxwell–Bloch system rogue waves on a periodic background
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Gravitational Wave Background from Extreme-Mass-Ratio Inspirals
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作者 Haoyu Zhao Yuanhao Zhang +1 位作者 Xilong Fan Wenbiao Han 《Chinese Physics Letters》 2025年第5期239-247,共9页
The gravitational wave background(GWB) produced by extreme-mass-ratio inspirals(EMRIs) serves as a powerful tool for probing the astrophysical and dynamical processes in galactic centers. EMRI systems are a primary ta... The gravitational wave background(GWB) produced by extreme-mass-ratio inspirals(EMRIs) serves as a powerful tool for probing the astrophysical and dynamical processes in galactic centers. EMRI systems are a primary target for the space-based detector laser interferometer space antenna due to their long-lived signals and high signal-to-noise ratios. This study explores the statistical properties of the GWB from EMRI, focusing on the calculation methods for the GWB, the astrophysical distribution of EMRI sources, and the influence of key parameters, including the spin of supermassive black holes(SMBHs) and the masses of compact objects(COs). By analyzing these factors, we determine the distribution range of the characteristic strain of the GWB from EMRIs. We find that the final eccentricity distributions appear to have negligible effect on the intensity of the GWB due to rapid circularization before they become detectable and the spin of the SMBH enhances the gravitational wave characteristic strain by approximately 1% compared to cases without spin effects. The masses of COs can also significantly affect the characteristic strain of the GWB from EMRIs, with black hole as CO producing a gravitational wave signal intensity that is approximately one order of magnitude higher compared to cases where neutron star or white dwarf are the COs. 展开更多
关键词 probing astrophysical dynamical processes galactic centers astrophysical distribution extreme mass ratio inspirals laser interferometer space antenna gravitational wave background calculation methods characteristic strain Laser Interferometer Space Antenna
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深化医改背景下基于岗位胜任力的静脉治疗专科护理培训对护士专科能力的影响
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作者 余海霞 王波 +2 位作者 孟利霞 冯珊珊 郭炜炜 《齐鲁护理杂志》 2026年第2期149-151,共3页
目的:探究深化医改背景下基于岗位胜任力的静脉治疗专科护理培训对护士专科能力的影响。方法:选取2023年3月—2024年9月90名在职护士为研究对象,按照随机数字表法分成观察组和对照组各45名,对照组实施常规护理培训,观察组在对照组基础... 目的:探究深化医改背景下基于岗位胜任力的静脉治疗专科护理培训对护士专科能力的影响。方法:选取2023年3月—2024年9月90名在职护士为研究对象,按照随机数字表法分成观察组和对照组各45名,对照组实施常规护理培训,观察组在对照组基础上实施深化医改背景下基于岗位胜任力的静脉治疗专科护理培训。观察比较两组护士岗位胜任力、患者满意度、临床应用能力。结果:观察组护士岗位胜任力、患者满意度、临床应用能力均高于对照组(P<0.01,P<0.05)。结论:采用基于岗位胜任力的静脉治疗专科护理培训,可提高护理人员的专科岗位胜任力、临床应用能力,从而提高患者满意度。 展开更多
关键词 深化医改背景 静脉治疗 专科护理培训 满意度
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Research on Background and Utilization of Germplasm Resources in Maize 被引量:3
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作者 杨培珠 钟国祥 +4 位作者 谢虹 陈少方 苏立生 刘惠娈 张旭 《Agricultural Science & Technology》 CAS 2011年第10期1464-1467,共4页
[Objective] The research aimed at introducing the background and utilization of germplasm resources in maize.[Method] The research progress on genetic background and utilization of maize germplasm resources was compre... [Objective] The research aimed at introducing the background and utilization of germplasm resources in maize.[Method] The research progress on genetic background and utilization of maize germplasm resources was comprehensively reviewed in this paper,including maize heterotic groups and heterotic patterns,their flexible application in breeding and the utilization of various types of original materials.[Result] The results show that germplasm resource is the premise and basis for maize breeding.In-depth understanding and a reasonable selection of germplasm resources can significantly improve the breeding efficiency and speed up the breeding process.At the same time,it is considered that the selection and construction of original materials in maize breeding can not be limited to the heterotic groups and heterotic patterns,but has to be used reasonablely according to different types of germplasm resources and individual breeding objective and idea as well.[Conclusion] This study had broadened the idea and provided inspiration for the maize breeding practice in China. 展开更多
关键词 MAIZE Germplasm resources Genetic background UTILIZATION
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Mitochondrial DNA D-loop Variation and Genetic Background of Brahman Cattle 被引量:1
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作者 亐开兴 吴桂生 +7 位作者 廖祥龙 金显栋 赵刚 杨国荣 袁希平 黄必志 文际坤 张亚平 《Zoological Research》 CAS CSCD 北大核心 2006年第6期615-620,共6页
The complete mitochondrial DNA D-loop sequences from 10 stud Brahman cattle were sequenced and analyzed. The results showed that the genetic diversity of Brahman cattle was rich ; the rate of nucleotide variation, hap... The complete mitochondrial DNA D-loop sequences from 10 stud Brahman cattle were sequenced and analyzed. The results showed that the genetic diversity of Brahman cattle was rich ; the rate of nucleotide variation, haplotype diversity and nucleotide diversity were 6.25%, 0.978± 0.054 and 0.014 30± 0.008 68, respectively. Nine haplotypes were defined and fell into two distinct lineages, suggesting that Brahman cattle have both Bos indicus (Zebu) and B. taurus genetic background. The taurine haplotypes were predominant at 90% and only Brah-6 belonged to the Asian zebu mthaplotype. This indicates that Brahman cattle was one of the zebu breeds and inherited the excellent characteristics of both the Asian zebu and European beef cattle, such as easy calf delivery, high quality beef, heat tolerance and resistance to various parasites. Breeders introduced Brahman cattle to improve the productivity and adaptability of native cattle. The Zebu has evidently frequently introgressed into the modem taurine breeds. As for modem zebu breeds, B. taurus also highly contributed to their formation, except for the Asian zebu. Furthermore our results also confirm the hypothesis that B. indicus has undergone a separate domestication event and originated from the Indian subcontinent. 展开更多
关键词 Brahman cattle mtDNA D-loop polymorphism genetic background
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