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Basal defense is enhanced in a wheat cultivar resistant to Fusarium head blight
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作者 Xinlong Gao fan li +7 位作者 Yikun Sun Jiaqi Jiang Xiaolin Tian Qingwen li Kaili Duan Jie lin Huiquan liu Qinhu Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1238-1258,共21页
Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat diseases.Besides directly affecting the yield,the mycotoxin residing in the kernel greatly threa... Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat diseases.Besides directly affecting the yield,the mycotoxin residing in the kernel greatly threatens the health of humans and livestock.Xinong 979(XN979)is a widely cultivated wheat elite with high yield and FHB resistance.However,its resistance mechanism remains unclear.In this study,we studied the expression of genes involved in plant defense in XN979 by comparative transcriptomics.We found that the FHB resistance in XN979 consists of two lines of defense.The first line of defense,which is constitutive,is knitted via the enhanced basal expression of lignin and jasmonic acid(JA)biosynthesis genes.The second line of defense,which is induced upon F.graminearum infection,is contributed by the limited suppression of photosynthesis and the struggle of biotic stress-responding genes.Meanwhile,the effective defense in XN979 leads to an inhibition of fungal gene expression,especially in the early infection stage.The formation of the FHB resistance in XN979 may coincide with the breeding strategies,such as selecting high grain yield and lodging resistance traits.This study will facilitate our understanding of wheat-F.graminearum interaction and is insightful for breeding FHB-resistant wheat. 展开更多
关键词 Fusarium head blight Xinong 979 LIGNIN jasmonic acid PHOTOSYNTHESIS Fusarium graminearum
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Milling degree affects the fermentation properties of rice:perspectives from the composition of nutrients and gut microbiota via in vitro fermentation
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作者 Yu Zhang fan li +7 位作者 Shutong Pan Bing Bai Kai Huang Sen li Hongwei Cao Tian Xie Jian Xie Xiao Guan 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1578-1588,共11页
Fermentation substrates of rice with different milling degrees(MDs) were prepared and fermented with human feces to compare their fermentation properties and effects on gut microbiota.MD 0s,MD 5s and MD 60s represente... Fermentation substrates of rice with different milling degrees(MDs) were prepared and fermented with human feces to compare their fermentation properties and effects on gut microbiota.MD 0s,MD 5s and MD 60s represented brown rice,moderately-milled rice and white rice,respectively.After in vitro fermentation,the MD 5s group showed higher starch utilization,compared with the MD 0s and 60s groups evaluated by Fourier transform infrared spectrometer,and confocal laser scanning microscope.Effects of fermentation substrates of rice with different MDs on gut microbiota were evaluated by 16S rDNA sequencing.All the sample groups reduced the pH and produced short-chain fatty acids(SCFAs) and branched-chain fatty acids.The MD 5s group exhibited higher α-diversity than the MD 0s and 60s groups.Abundances of Phascolarctobacterium,Blautia and norank_f_Ruminococcaceae were higher in the MD 0s and 5s groups,compared with the MD 60s group.These bacteria were also positively correlated with the SCFAs production via Spearman correlation analysis.In vitro culture assay revealed that fermentation substrates of MD 0s and 5s promoted the growth of two probiotics(Akkermansia muciniphila and Bifidobacterium adolescentis).Our results showed that moderate milling might be an appropriate way to produce rice products with richer nutrients and better fermentation properties. 展开更多
关键词 Rice processing MILLING Whole grains Gut microbiota
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Mucosa color and size may indicate malignant transformation of chicken skin mucosa-positive colorectal neoplastic polyps
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作者 Ying-Jie Zhang Meng-Xia Yuan +5 位作者 Wu Wen fan li Yi Jian Chuan-Ming Zhang Ye Yang Feng-lin Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期750-760,共11页
BACKGROUND Lipid metabolism reprogramming is suspected to exist in pre-cancerous lesions,including colorectal adenoma.Screening colonoscopy frequently reveals chicken skin mucosa(CSM;white or yellow-white speckled muc... BACKGROUND Lipid metabolism reprogramming is suspected to exist in pre-cancerous lesions,including colorectal adenoma.Screening colonoscopy frequently reveals chicken skin mucosa(CSM;white or yellow-white speckled mucosa)surrounding colo-rectal polyps,caused by macrophages engulfing and accumulating the lipids decomposed by colon cells or adjacent tumors.CSM-positive colorectal polyps are associated with various diseases;however,their prognosis varies greatly.Cold snare polypectomy is commonly used to resect lesions up to 10 to 15 mm in diameter without signs of submucosal invasion but is controversial for CSM-positive colorectal polyps.Improved imaging is required to diagnose and treat CSM-positive colorectal polyps.METHODS This retrospective cohort study included 177 patients with CSM-positive colorectal polyps diagnosed using endoscopy.All patient-related information was extracted from the Goldisc soft-clinic DICOM system or electronic medical record system.Based on the pathological results,patients were classified as non-neoplastic polyps(five juvenile polyps),neoplastic polyps,non-invasive high-grade neoplasia(NHGN),or submucosal invasive carcinoma(SM stage cancer).We analyzed and compared the clinical features,suspected risk factors for malignant transformation of neoplastic polyps,and early infiltration of sub-mucosal carcinoma.RESULTS The diameters of NHGN and SM polyps were much smaller than those of neoplastic polyps.Most NHGN polyps had a deeper red mucosal color.On logistic regression analyses,diameter and deeper red mucosal color were independent risk factors for malignant transformation of neoplastic polyps.Type 1 CSM was more common in high-grade intraepithelial neoplasia and SM;type 2 CSM was more common in neoplastic polyps.Logistic regression analyses revealed no significant differences in the malignant transformation of neoplastic polyps or early submucosal invasion of CSM-positive colorectal cancer.Changes in the CSM mucosa surrounding neoplastic polyps and submucosal invasion of colorectal cancer disappeared within 12 months.No tumor recurrence was found during either partial or complete endoscopic resection of the CSM.CONCLUSION CSM-positive colorectal polyps>1 cm in diameter or with deeper red mucosa may be related to NHGN.Resection of CSM surrounding colorectal adenomas did not affect tumor recurrence. 展开更多
关键词 Chicken skin mucosa Colorectal cancer Colorectal polyps Endoscopic resection Malignant transformation White light endoscopy
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Malignancy risk factors and prognostic variables of pancreatic mucinous cystic neoplasms in Chinese patients
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作者 Qing Xia fan li +4 位作者 Rui Min Shuai Sun Yue-Xin Han Zhen-Zhong Feng Nan li 《World Journal of Gastroenterology》 SCIE CAS 2023年第20期3119-3132,共14页
BACKGROUND Pancreatic mucinous cystic neoplasms(MCNs)represent one of the precursor lesions of pancreatic ductal adenocarcinoma,and their detection has been facilitated by advances in preoperative imaging.Due primaril... BACKGROUND Pancreatic mucinous cystic neoplasms(MCNs)represent one of the precursor lesions of pancreatic ductal adenocarcinoma,and their detection has been facilitated by advances in preoperative imaging.Due primarily to the rarity of MCNs,however,there is limited knowledge regarding the prognostic variables and high-risk factors for malignant transformation.A more comprehensive and nuanced approach is necessary to fill this gap and provide a basis for improved treatment decisions and patient outcomes.AIM To investigate the high-risk factors associated with malignant MCNs and to explore the prognostic factors of MCN with associated invasive carcinoma(MCNAIC).METHODS All cases of resected MCNs from a single high-volume institution between January 2012 and January 2022 were retrospectively reviewed.Only cases with ovarian-type stroma verified by progesterone receptor staining were included.Preoperative features,histological findings and postoperative course were documented.Multivariate logistic regression was employed to investigate variables related to malignancy.Survival analysis was performed using the Kaplan-Meier curve,and the prognostic factors were assessed to evaluate the postoperative course of patients with MCN-AIC.RESULTS Among the 48 patients,36 had benign MCNs,and 12 had malignant MCNs(1 high-grade atypical hyperplasia and 11 MCN-AIC).Age,tumour size,presence of solid components or mural nodules and pancreatic duct dilatation were identified as independent risk factors associated with malignancy.The follow-up period ranged from 12 mo to 120 mo,with a median overall survival of 58.2 mo.Only three patients with MCN-AIC died,and the 5-year survival rate was 70.1%.All 11 cases of MCN-AIC were stage I,and extracapsular invasion was identified as a prognostic factor for poorer outcomes.CONCLUSION The risk factors independently associated with malignant transformation of MCNs included age,tumour size,presence of solid components or mural nodules,and pancreatic duct dilatation.Our study also revealed that encapsulated invasion was a favourable prognostic factor in MCN-AIC patients. 展开更多
关键词 Mucinous cystic neoplasms Pancreatic adenocarcinoma Invasive carcinoma Risk of malignancy Prognostic factor Retrospective study
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Mechanical and Permeability Analysis and Optimization of Recycled Aggregate Pervious Concrete Based on Response Surface Method
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作者 fan li Xin Cai +2 位作者 Yanan Zhang Xingwen Guo Minmin Jiang 《Journal of Renewable Materials》 SCIE EI 2023年第4期1745-1762,共18页
In this paper,the effects of different influencing factors and factor interaction on the compressive strength and permeability of recycled aggregate pervious concrete(RAPC)were studied based on the response surface me... In this paper,the effects of different influencing factors and factor interaction on the compressive strength and permeability of recycled aggregate pervious concrete(RAPC)were studied based on the response surface method(RSM).By selecting the maximum aggregate size,water cement ratio and target porosity as design variables,combined with laboratory tests and numerical analysis,the influences of three factors on the compressive strength and permeability coefficient of RAPC were revealed.The regression equation of compressive strength and permeability coefficient of recycled aggregate pervious concrete were established based on RSM,and the response surface model was optimized to determine the optimal ratio of RAPC under the conditions of meeting the mechanical and permeability properties.The results show that the mismatch item of the model is not significant,the model is credible,and the accuracy and reliability of the test are high,but the degree of uncorrelation between the test data and the model is not obvious.The sensitivity of the three factors to the compressive strength is water cement ratio>maximum coarse aggregate particle size>target porosity,and the sensitivity to the permeability coefficient is target porosity>maximum coarse aggregate particle size>water cement ratio.The absolute errors of the model prediction results and the model optimization results are 1.28 MPa and 0.19 mm/s,and the relative errors are 5.06%and 4.19%,respectively.With high accuracy,RSM can match the measured results of compressive strength and permeability coefficient of RAPC. 展开更多
关键词 Recycled aggregate pervious concrete(RAPC) response surface method(RSM) MECHANICAL PERMEABILITY OPTIMIZATION
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Bubble nucleation in spherical liquid cavity wrapped by elastic medium
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作者 张先梅 李凡 +5 位作者 王成会 胡静 莫润阳 沈壮志 郭建中 林书玉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期323-332,共10页
According to classical nucleation theory, gas nuclei can generate and grow into a cavitation bubble when the liquid pressure exceeds a threshold. However, classical nucleation theory does not include boundary effects.... According to classical nucleation theory, gas nuclei can generate and grow into a cavitation bubble when the liquid pressure exceeds a threshold. However, classical nucleation theory does not include boundary effects. An enclosed spherical liquid cavity surrounded by elastic medium is introduced to model the nucleation process in tissue. Based on the equilibrium pressure relationship of a quasi-static process, the expressions of the threshold and the modified nucleation rate are derived by considering the tissue elasticity. It is shown that the constraint plays an important role in the nucleation process. There is a positive correlation between nucleation threshold pressure and constraint, which can be enhanced by an increasing tissue elasticity and reducing the size of the cavity. Meanwhile, temperature is found to be a key parameter of nucleation process, and cavitation is more likely to occur in confined liquids at temperature T > 100℃. In contrast, less influences are induced by these factors, such as bulk modulus, liquid cavity size, and acoustic frequency. Although these theoretical predictions of the thresholds have been demonstrated by many previous researches, much lower thresholds can be obtained in liquids containing dissolved gases, e.g., the nucleation threshold is about-21 MPa in a liquid of 0.8-nm gas nuclei at room temperature. Moreover, when there is a gas nucleus of 20 nm, the theoretical threshold pressure might be less than1 MPa. 展开更多
关键词 elastic confinement liquid cavities cavitation nucleation
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“果树育种学”课程思政建设路径探索与实践
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作者 樊丽 张磊 刘艳 《教育教学论坛》 2024年第2期93-96,共4页
立德树人是高校立身之本,所有课程都有育人功能。课程思政是学校发挥专业课程德育作用的有效平台。“果树育种学”是园艺专业的核心课程,学术性强,内容深奥。从“提升教师的思想政治意识和业务能力;深度挖掘课程中蕴含的思政元素,编制... 立德树人是高校立身之本,所有课程都有育人功能。课程思政是学校发挥专业课程德育作用的有效平台。“果树育种学”是园艺专业的核心课程,学术性强,内容深奥。从“提升教师的思想政治意识和业务能力;深度挖掘课程中蕴含的思政元素,编制典型教学案例;丰富教学手段,改进教学环境;把实践教学与课程思政相结合;实行多元化考核评价体系”等五个方面进行课程思政建设路径的探索与实践,取得了良好的教学效果,构建了“果树育种学”课程思政可行性框架,以期为同类课程思政建设提供借鉴和参考。 展开更多
关键词 果树育种学 课程思政 教学手段 教学评价 教学改革
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虚拟同步机控制策略下的STATCOM相间电容电压平衡方法研究
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作者 范利 刘惠康 +1 位作者 柴琳 陈天宇 《电力电容器与无功补偿》 2024年第2期44-51,共8页
针对基于直挂式级联H桥拓扑结构的静止同步补偿器在运行时产生的相间电容电压不平衡的问题,本文在虚拟同步机的控制策略基础上提出了一种平衡相间电容电压的方法。虚拟同步机具有响应速度快的优点,但用于静止同步补偿器来作无功补偿时... 针对基于直挂式级联H桥拓扑结构的静止同步补偿器在运行时产生的相间电容电压不平衡的问题,本文在虚拟同步机的控制策略基础上提出了一种平衡相间电容电压的方法。虚拟同步机具有响应速度快的优点,但用于静止同步补偿器来作无功补偿时会产生相间电容电压不平衡的问题。因此本文首先引入电容电压平均值来完成虚拟同步机的快速并网,其次将虚拟同步机算法的无功调节分为3部分来实现分相无功补偿,再在电压合成前引入电容电压平均值作反馈,以实现相间电容电压平衡。最后在Matlab/Simulink环境下搭建仿真模型,验证了所提控制策略能有效解决相间电容电压不平衡问题,并且仿真结果表明所提控制策略具有良好的动态响应特性。 展开更多
关键词 静止同步补偿器 虚拟同步机控制策略 相间电容电压平衡 级联H桥变换器
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高强度聚焦超声治疗子宫腺肌症的研究进展
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作者 范丽 史小荣 《安徽医药》 CAS 2024年第1期22-26,共5页
子宫腺肌症是指子宫内膜腺体及间质侵入子宫肌层中,一般为弥漫性生长;常见于30~50岁妇女。子宫腺肌症的治疗包括药物治疗、手术治疗及微创治疗,其中高强度聚焦超声(HIFU)是一种微创治疗手段,目前已用于多种妇科疾病的治疗。其原理是通... 子宫腺肌症是指子宫内膜腺体及间质侵入子宫肌层中,一般为弥漫性生长;常见于30~50岁妇女。子宫腺肌症的治疗包括药物治疗、手术治疗及微创治疗,其中高强度聚焦超声(HIFU)是一种微创治疗手段,目前已用于多种妇科疾病的治疗。其原理是通过皮肤贴合的体外治疗探头,在不损伤毗邻组织的前提下,将能量汇聚于靶区,产生一系列的效应,使靶区组织变性、坏死,以达到治疗目的。目前对其治疗只能是充分了解子宫腺肌症的临床症状,尽量早期诊断,临床干预,对症治疗,改善预后。现对HIFU治疗子宫腺肌症进行简要概述。 展开更多
关键词 子宫腺肌病 高强聚焦超声消融 腹痛 痛经 糖蛋白类 治疗结果
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夜磨牙相关研究现况
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作者 赵力博 韩海平 +2 位作者 赵哲 范利 刘霖 《中国临床保健杂志》 CAS 2024年第1期127-131,共5页
夜磨牙在生活中很常见,其发病率大致随着年龄的增长而降低。夜磨牙病因复杂多样,相关生物学机制包括焦虑抑郁、睡眠障碍等。目前不同研究之间,对夜磨牙的定义和诊断标准并不完全一致。长期磨牙可引起牙冠磨损、牙敏感、牙周炎等并发症,... 夜磨牙在生活中很常见,其发病率大致随着年龄的增长而降低。夜磨牙病因复杂多样,相关生物学机制包括焦虑抑郁、睡眠障碍等。目前不同研究之间,对夜磨牙的定义和诊断标准并不完全一致。长期磨牙可引起牙冠磨损、牙敏感、牙周炎等并发症,会导致颞下颌关节紊乱、咀嚼肌疲劳压痛、咬肌肥大、头颈疼痛等,同时磨牙可能与心血管不良事件相关。该文主要介绍夜磨牙相关研究情况,帮助正确认识该病,了解夜磨牙的影响因素、身体危害和治疗方法,关注其与睡眠情况的相互影响,突出个体化的病因干预,实施有效的多科联合治疗方案。 展开更多
关键词 夜磨牙症 影响因素分析 睡眠障碍 综述
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基于深度教学的地理情境梯度标准与创设策略
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作者 李琳 刘守江 +3 位作者 袁章棋 张蕊杰 樊丽 翁子翔 《地理教学》 北大核心 2024年第1期19-22,共4页
地理情境梯度是学生认知进阶发展的“脚踏点”,为探寻学生的认知过程、评估学生的认知水平提供了载体。本文从深度教学的视角,说明设置梯度式地理情境的必要性;从地理情境的参量构成和地理核心素养,构建地理情境梯度的层级标准。本文以... 地理情境梯度是学生认知进阶发展的“脚踏点”,为探寻学生的认知过程、评估学生的认知水平提供了载体。本文从深度教学的视角,说明设置梯度式地理情境的必要性;从地理情境的参量构成和地理核心素养,构建地理情境梯度的层级标准。本文以“区域发展对交通运输布局的影响”为例,设定“区域情境促认知”“问题情境促探究”“综合情境促反思”三个相互关联的梯度情境,促使教师深度教学和学生深度学习的落地。 展开更多
关键词 深度教学 认知进阶 高中地理 情境梯度
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地理可测量教学目标对高中生目标达成度的影响
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作者 樊丽 刘守江 敬大海 《地理教学》 北大核心 2024年第3期44-47,共4页
为研究可测量教学目标对学生学习效率的影响,本文以教学目标的表述形式为自变量,通过定量研究分析可测量教学目标与常规教学目标在班级目标达成度方面的差异。研究发现可测量教学目标更有利于达成教学目标,并且在抑制学习的两极分化方... 为研究可测量教学目标对学生学习效率的影响,本文以教学目标的表述形式为自变量,通过定量研究分析可测量教学目标与常规教学目标在班级目标达成度方面的差异。研究发现可测量教学目标更有利于达成教学目标,并且在抑制学习的两极分化方面具有显著优势,能弥补学生基础学习水平的不足。基于此,本文提出相应的教学目标设计的改进建议,并为可测量教学目标在实际课堂中的应用提供实证案例支撑。 展开更多
关键词 可测量教学目标 高中地理 目标达成度
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高等教育振兴推动了地方经济增长吗?——来自中西部高等教育振兴计划的准自然实验
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作者 樊丽 邹琪 《中国人民大学教育学刊》 2024年第1期163-180,共18页
高等教育与经济的多元关系为我国社会转型与教育制度变革提供多重路径。基于中西部高等教育振兴计划的准自然实验,使用2008—2019年我国285个城市面板数据,运用渐进性双重差分法,考察高等教育振兴与地方经济增长之间的因果关系。研究发... 高等教育与经济的多元关系为我国社会转型与教育制度变革提供多重路径。基于中西部高等教育振兴计划的准自然实验,使用2008—2019年我国285个城市面板数据,运用渐进性双重差分法,考察高等教育振兴与地方经济增长之间的因果关系。研究发现,中西部高等教育振兴计划显著促进了地方经济增长,但这种经济增长效应仅作用于西部城市和一二三线城市,对东中部城市以及四五线城市的影响并不显著。从作用机制来看,技术创新效应和产业结构优化效应是高等教育振兴影响地方经济增长的两条重要路径。因此,政府应当有序提升中西部高等教育振兴计划实施广度和深度,不断增强中西部高校振兴计划与地方发展现状的契合度,并不断完善中西部高等教育振兴计划服务地方经济增长的支撑体系,以此优化高等教育资源配置,缩小经济发展差距,实现共同富裕。 展开更多
关键词 高等教育振兴 经济增长 中西部 双重差分
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Recurrent neural network decoding of rotated surface codes based on distributed strategy
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作者 李帆 李熬庆 +1 位作者 甘启迪 马鸿洋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期322-330,共9页
Quantum error correction is a crucial technology for realizing quantum computers.These computers achieve faulttolerant quantum computing by detecting and correcting errors using decoding algorithms.Quantum error corre... Quantum error correction is a crucial technology for realizing quantum computers.These computers achieve faulttolerant quantum computing by detecting and correcting errors using decoding algorithms.Quantum error correction using neural network-based machine learning methods is a promising approach that is adapted to physical systems without the need to build noise models.In this paper,we use a distributed decoding strategy,which effectively alleviates the problem of exponential growth of the training set required for neural networks as the code distance of quantum error-correcting codes increases.Our decoding algorithm is based on renormalization group decoding and recurrent neural network decoder.The recurrent neural network is trained through the ResNet architecture to improve its decoding accuracy.Then we test the decoding performance of our distributed strategy decoder,recurrent neural network decoder,and the classic minimum weight perfect matching(MWPM)decoder for rotated surface codes with different code distances under the circuit noise model,the thresholds of these three decoders are about 0.0052,0.0051,and 0.0049,respectively.Our results demonstrate that the distributed strategy decoder outperforms the other two decoders,achieving approximately a 5%improvement in decoding efficiency compared to the MWPM decoder and approximately a 2%improvement compared to the recurrent neural network decoder. 展开更多
关键词 quantum error correction rotated surface code recurrent neural network distributed strategy
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Behaviors of cavitation bubbles driven by high-intensity ultrasound
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作者 黄晨阳 李凡 +5 位作者 冯释毅 王成会 陈时 胡静 何芯蕊 宋家凯 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期394-404,共11页
In a multi-bubble system, the bubble behavior is modulated by the primary acoustic field and the secondary acoustic field. To explore the translational motion of bubbles in cavitation liquids containing high-concentra... In a multi-bubble system, the bubble behavior is modulated by the primary acoustic field and the secondary acoustic field. To explore the translational motion of bubbles in cavitation liquids containing high-concentration cavitation nuclei,evolutions of bubbles are recorded by a high-speed camera, and translational trajectories of several representative bubbles are traced. It is found that translational motion of bubbles is always accompanied by the fragmentation and coalescence of bubbles, and for bubbles smaller than 10 μm, the possibility of bubble coalescence is enhanced when the spacing of bubbles is less than 30 μm. The measured signals and their spectra show the presence of strong negative pressure, broadband noise,and various harmonics, which implies that multiple interactions of bubbles appear in the region of high-intensity cavitation.Due to the strong coupling effect, the interaction between bubbles is random. A simplified triple-bubble model is developed to explore the interaction patterns of bubbles affected by the surrounding bubbles. Patterns of bubble interaction, such as attraction, repulsion, stable spacing, and rebound of bubbles, can be predicted by the theoretical analysis, and the obtained results are in good agreement with experimental observations. Mass exchange between the liquid and bubbles as well as absorption in the cavitation nuclei also plays an important role in multi-bubble cavitation, which may account for the weakening of the radial oscillations of bubbles. 展开更多
关键词 ultrasonic cavitation multi-bubble system translational motion of bubbles
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我国食品中放射性核素检验及污染暴露水平
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作者 傅骏青 高牡丹 +3 位作者 范丽 程月红 杨振东 胡明燕 《食品安全质量检测学报》 CAS 2024年第3期165-173,共9页
核污染水对海洋的污染会随着食物链蔓延,食品中的放射性污染对人类的危害大且影响深远,监测食品中放射性污染情况对保障公众健康、维护食品安全具有极其重要的意义。我国制定了主要放射性核素的检验标准和限量标准,基本形成食品放射性... 核污染水对海洋的污染会随着食物链蔓延,食品中的放射性污染对人类的危害大且影响深远,监测食品中放射性污染情况对保障公众健康、维护食品安全具有极其重要的意义。我国制定了主要放射性核素的检验标准和限量标准,基本形成食品放射性监测体系。近5年相关研究显示,我国各地区食品中放射性污染水平在可接受范围内,核设施、核能发电厂、矿山等重点区域周边食品的放射性污染状况均未对人群造成负担,暂未发生食品安全问题。本文总结了食品中放射性核素的种类、来源与危害,分析食品中放射性核素污染的国内外现行标准限量及检验方法,综述了我国食品中放射性污染现状的研究,为进一步研究放射性核素、制定完善标准体系提供技术支撑,为核辐射的应急管理提供数据支持。 展开更多
关键词 放射性核素 食品污染 暴露水平 食品安全 标准
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三峡库区陆地生态系统净初级生产力时空演变及其影响因素
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作者 范莉 叶钊 +2 位作者 祝好 张继 朱玉涵 《中国农业气象》 CSCD 2024年第5期493-505,共13页
陆地生态系统碳循环是全球及区域气候变化及人类活动影响研究的重要内容,三峡库区作为长江流域重要的生态环境保护和修复区域,在全球及区域碳循环和气候变化研究中发挥着极其重要的作用。本文基于2000-2021年太阳辐射、气温、CO_(2)浓... 陆地生态系统碳循环是全球及区域气候变化及人类活动影响研究的重要内容,三峡库区作为长江流域重要的生态环境保护和修复区域,在全球及区域碳循环和气候变化研究中发挥着极其重要的作用。本文基于2000-2021年太阳辐射、气温、CO_(2)浓度及归一化植被指数等数据,依据C-FIX模型,调整参数建立三峡库区(重庆段)陆地生态系统净初级生产力(NPP)估算模型,引入重心模型、趋势分析等方法定量分析2000-2021年植被NPP时空变化特征,同时利用相关分析方法结合Miami模型定量区分气候变化与人类活动影响NPP的相对作用。结果表明:(1)研究区植被NPP整体呈波动上升趋势,有94%的区域植被NPP变化趋势率为正值,集中分布于长江沿线及以北的大部地区。2000-2021年区域年平均NPP由666.02gC·m^(-2)增加至809.04gC·m^(-2),增幅为17.68%。(2)研究区NPP空间分布整体呈现由东北向西南逐渐递减的格局,年平均NPP767.3gC·m^(-2)·a^(-1),其中NPP>800gC·m^(-2)·a^(-1)的区域占研究区总面积的46%,主要分布在海拔400-900m的区域。(3)研究区植被NPP重心呈现出由西南向东北移动的趋势,说明东北部植被NPP增量和增速高于中西部。(4)研究区植被NPP变化对气温作用更为敏感,植被NPP与年气温的偏相关系数为-0.68~0.94,呈正相关区域占比高达95.6%。植被NPP与年降水量的偏相关系数为-0.83~0.82,呈正相关区域占比75.7%,分布于长江沿线以北的大部地区及武隆和涪陵的大部区域。(5)气候变化和人类活动对研究区植被NPP变化过程的相对作用存在显著的空间异质性,处于植被恢复状态的区域占总面积的93.63%,其中45.24%的区域受气候变化影响,46.72%的植被恢复区由气候变化和人类活动两者共同作用促成。 展开更多
关键词 C-FIX模型 NPP 重心模型 时空变化 三峡库区 驱动机制
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冠心病合并2型糖尿病的老年患者综合管理
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作者 范利 孔晓晅 《中国临床保健杂志》 CAS 2024年第1期1-4,共4页
随着全球人口老龄化,多病共存的现象明显增加,其中冠心病合并2型糖尿病(以下简称“心糖”共病)的老年患者较为多发,既影响患者的身心健康,增加了衰弱失能的风险,导致住院率、病死率升高,又给社会、家庭带来了沉重的照护和经济负担,已成... 随着全球人口老龄化,多病共存的现象明显增加,其中冠心病合并2型糖尿病(以下简称“心糖”共病)的老年患者较为多发,既影响患者的身心健康,增加了衰弱失能的风险,导致住院率、病死率升高,又给社会、家庭带来了沉重的照护和经济负担,已成为社会重大的公共卫生问题。在临床实践中,“心糖”共病使诊疗的复杂性增加,迫切需要进行综合管理。 展开更多
关键词 慢性病共病 冠心病 糖尿病 2型 疾病管理 老年人
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基于“四轮驱动模式”的大学生创新能力培养模式研究与实践
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作者 张营营 叶继红 +4 位作者 喻秋 贾福萍 范力 杜健民 李贤 《高等建筑教育》 2024年第1期44-49,共6页
立德树人是高校的根本使命。本科阶段是科研创新型人才培养的关键时期,而学科竞赛是提高本科生科研创新能力、培养创新型人才的重要环节。基于中国矿业大学力学与土木工程学院的多年实践经验,提出了以“学科竞赛+课程建设+大创项目+制... 立德树人是高校的根本使命。本科阶段是科研创新型人才培养的关键时期,而学科竞赛是提高本科生科研创新能力、培养创新型人才的重要环节。基于中国矿业大学力学与土木工程学院的多年实践经验,提出了以“学科竞赛+课程建设+大创项目+制度保障”四轮驱动模式的大学生创新能力培养模式,多层次、递进式地培养大学生的创新实践能力,也能够有效鼓励学生个性化发展,促使人才培养质量从“单一型、封闭型、知识灌输型”向“复合型、开放型、能力创新型”转化,真正树立起开拓创新的科学理念,最终达到“知识和技能传授”与“科研创新素质培养”并重的教学目的。 展开更多
关键词 四轮驱动模式 创新能力 学科竞赛 人才培养模式
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HPLC法同时测定盐酸阿霉素与氯尼达明的含量
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作者 孙雨菡 许子艺 +3 位作者 廖峻 张翮 樊莉 鲁莹 《药学实践与服务》 CAS 2024年第3期127-130,共4页
目的建立同时测定盐酸阿霉素(DOX·HCl)与氯尼达明(LND)含量的测定方法。方法采用HPLC法,色谱柱为Agilent 5 HC-C_(18)(2)(4.6 mm×250 mm,5μm),流动相为甲醇-0.1%TFA水溶液,梯度洗脱,甲醇比例随时间变化为:0~3 min,65%甲醇;3~... 目的建立同时测定盐酸阿霉素(DOX·HCl)与氯尼达明(LND)含量的测定方法。方法采用HPLC法,色谱柱为Agilent 5 HC-C_(18)(2)(4.6 mm×250 mm,5μm),流动相为甲醇-0.1%TFA水溶液,梯度洗脱,甲醇比例随时间变化为:0~3 min,65%甲醇;3~7 min,65%→90%甲醇;7~13 min,90%甲醇;13~15 min,90%→65%甲醇;15~20 min、65%甲醇。采集时间20 min,平衡时间3 min,紫外检测波长205 nm及253 nm,流速1.0 ml/min,柱温35℃,进样量:10μl。结果该方法专属性好,盐酸阿霉素在1~40μg/ml的浓度范围内线性良好,氯尼达明在6~240μg/ml的浓度范围内线性良好。该方法之下,两种化合物的精密度、稳定性、回收率均符合要求。结论建立了同时检测盐酸阿霉素与氯尼达明含量的液相分析方法,该方法专属性强,准确可靠。 展开更多
关键词 氯尼达明 盐酸阿霉素 高效液相色谱法 联合用药 梯度洗脱
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