期刊文献+
共找到61篇文章
< 1 2 4 >
每页显示 20 50 100
露地辣椒生产固碳增活全程施肥方案
1
作者 李若楠 王丽英 +5 位作者 史建硕 陈莉 李建芬 贾舟 蒋龙刚 李桃 《中国果菜》 2024年第7期74-80,共7页
河北露地辣椒种植历史悠久,但生产中粗放的养分管理,导致土壤有机质消耗,植株抗逆性差,连作障碍频发。本文基于露地辣椒生产固碳增活施肥技术,围绕肥料养分均衡减量、有机替代固碳增效、菌剂滴灌沃土增活3项核心内容,从肥料养分总量推... 河北露地辣椒种植历史悠久,但生产中粗放的养分管理,导致土壤有机质消耗,植株抗逆性差,连作障碍频发。本文基于露地辣椒生产固碳增活施肥技术,围绕肥料养分均衡减量、有机替代固碳增效、菌剂滴灌沃土增活3项核心内容,从肥料养分总量推荐、有机物料多源配施、滴灌肥水协同运筹等方面制定了河北露地辣椒生产固碳增活全程施肥解决方案,并对比四种固碳技术模式应用效果,发现基施多样化来源的有机物料朝天椒增产效果优于单一有机物料,优选牛粪堆肥+秸秆类生物炭模式或牛粪堆肥+玉米秸秆+秸秆类生物炭技术模式(秸秆还田条件),以助力传统辣椒产区耕地保护与土壤质量提升,促进种植户养分管理由盲目粗放向合理精准转变。 展开更多
关键词 露地辣椒 固碳增活 有机肥料 菌剂 滴灌
下载PDF
河北省露地菜田固碳增活对策及解决方案
2
作者 李若楠 王丽英 +3 位作者 史建硕 陈莉 贾舟 孙璇 《河北农业科学》 2024年第3期45-49,88,共6页
河北省是蔬菜生产大省,但露地蔬菜生产中养分管理较为粗放,长期存在有机物料施用种类单一、偏施化学氮肥、肥料养分配比失衡等问题,导致土壤有机质水平低、有效养分供应能力弱、连作障碍频发。针对露地蔬菜生产中存在的施肥问题,建立了... 河北省是蔬菜生产大省,但露地蔬菜生产中养分管理较为粗放,长期存在有机物料施用种类单一、偏施化学氮肥、肥料养分配比失衡等问题,导致土壤有机质水平低、有效养分供应能力弱、连作障碍频发。针对露地蔬菜生产中存在的施肥问题,建立了固碳增效与沃土增活综合施肥技术,制定了全程施肥解决方案。有助于改善与提升菜田土壤质量,促进蔬菜稳产增产和菜农增收,具有广阔的应用前景。 展开更多
关键词 露地蔬菜 土壤固碳增活 施肥技术 全程施肥解决方案
下载PDF
斜拉桥钢塔地震损伤特性及输入地震动参数的影响
3
作者 郏洲 谢旭 +1 位作者 王天佳 成程 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2024年第4期817-827,共11页
以主跨为165 m的独塔钢斜拉桥为研究对象,建立精细化钢塔计算模型.选取经峰值加速度调整后的历史地震记录作为地震动输入,分析顺桥向弹塑性时程反应,研究钢塔的钢板局部失稳以及超低周疲劳开裂特性,讨论纤维模型的适用性.结果表明,沿高... 以主跨为165 m的独塔钢斜拉桥为研究对象,建立精细化钢塔计算模型.选取经峰值加速度调整后的历史地震记录作为地震动输入,分析顺桥向弹塑性时程反应,研究钢塔的钢板局部失稳以及超低周疲劳开裂特性,讨论纤维模型的适用性.结果表明,沿高度方向加载的Pushover法能够预测钢塔顺桥向地震塑性发展的顺序和位置;纤维模型能够获得钢塔的弹塑性地震位移反应以及地震损伤位置,不能精确评价结构残余变形与损伤程度;输入地震动的峰值地面速度(PGV)/峰值地面加速度(PGA)值是影响结构地震损伤程度的指标;当PGA相同时,PGV/PGA值越大的地震动引起的钢塔地震损伤越显著,钢塔斜拉桥抗震性能验算应选用PGV/PGA值大的地震动时程. 展开更多
关键词 钢塔 地震损伤 近断层地震动 钢板局部失稳 超低周疲劳损伤
下载PDF
Glymphatic function and its influencing factors in different glucose metabolism states 被引量:1
4
作者 Bin Tian Chen Zhao +7 位作者 jia-Li Liang Hui-Ting Zhang Yi-Fan Xu Hui-Lei Zheng jia zhou jiang-Nian Gong Shu-Ting Lu Zi-San Zeng 《World Journal of Diabetes》 SCIE 2024年第7期1537-1550,共14页
BACKGROUND Dysfunction of the glymphatic system in the brain in different stages of altered glucose metabolism and its influencing factors are not well characterized.AIM To investigate the function of the glymphatic s... BACKGROUND Dysfunction of the glymphatic system in the brain in different stages of altered glucose metabolism and its influencing factors are not well characterized.AIM To investigate the function of the glymphatic system and its clinical correlates in patients with different glucose metabolism states,the present study employed diffusion tensor imaging along the perivascular space(DTI-ALPS)index.METHODS Sample size was calculated using the pwr package in R software.This crosssectional study enrolled 22 patients with normal glucose metabolism(NGM),20 patients with prediabetes,and 22 patients with type 2 diabetes mellitus(T2DM).A 3.0T magnetic resonance imaging was used to evaluate the function of the glymphatic system.The mini-mental state examination(MMSE)was used to assess general cognitive function.The DTI-ALPS index of bilateral basal ganglia and the mean DTI-ALPS index was calculated.Further,the correlation between DTI-ALPS and clinical features was assessed.RESULTS The left-side,right-side,and mean DTI-ALPS index in the T2DM group were significantly lower than that in the NGM group.The right-side DTI-ALPS and mean DTI-ALPS index in the T2DM group were significantly lower than those in the prediabetes group.DTI-ALPS index lateralization was not observed.The MMSE score in the T2DM group was significantly lower than that in the NGM and prediabetes group.After controlling for sex,the left-side DTI-ALPS and mean DTI-ALPS index in the prediabetes group were positively correlated with 2-hour postprandial blood glucose level;the left-side DTI-ALPS index was negatively correlated with total cholesterol and low-density lipoprotein level.The right-side DTI-ALPS and mean DTI-ALPS index were negatively correlated with the glycosylated hemoglobin level and waist-to-hip ratio in the prediabetes group.The left-side,right-side,and mean DTI-ALPS index in the T2DM group were positively correlated with height.The left-side and mean DTIALPS index in the T2DM group were negatively correlated with high-density lipoprotein levels.CONCLUSION Cerebral glymphatic system dysfunction may mainly occur in the T2DM stage.Various clinical variables were found to affect the DTI-ALPS index in different glucose metabolism states.This study enhances our understanding of the pathophysiology of diabetic brain damage and provides some potential biological evidence for its early diagnosis. 展开更多
关键词 Glymphatic system PREDIABETES Type 2 diabetes mellitus Magnetic resonance imaging Diffusion tensor imaging along the perivascular space
下载PDF
Effect of the extrahepatic bile duct anatomy on choledocholithiasis and its clinical significance
5
作者 Zheng Cao jia zhou +2 位作者 Li Wei Hai-Yu He Jun Li 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第5期1363-1370,共8页
BACKGROUND A comprehensive understanding of the extrahepatic bile duct anatomy is vital to guide surgical procedures and perform endoscopic retrograde cholangiography.Anatomical irregularities within the extrahepatic ... BACKGROUND A comprehensive understanding of the extrahepatic bile duct anatomy is vital to guide surgical procedures and perform endoscopic retrograde cholangiography.Anatomical irregularities within the extrahepatic bile duct may increase susceptibility to bile duct stones.AIM To investigate the anatomical risk factors associated with extrahepatic bile ducts in patients diagnosed with choledocholithiasis,with a specific focus on preventing stone recurrence after surgical intervention and endoscopic lithotomy.METHODS We retrospectively analyzed the medical records of 124 patients without choledocholithiasis and 108 with confirmed choledocholithiasis who underwent magnetic resonance cholangiopancreatography examinations at our center between January 2022 and October 2022.Logistic regression analyses were conducted to identify the anatomical risk factors influencing the incidence of common bile duct stones.RESULTS Multivariate logistic regression analysis revealed that several factors independently contributed to choledocholithiasis risk.Significant independent risk factors for choledocholithiasis were diameter of the common hepatic[adjusted odds ratio(aOR)=1.43,95%confidence interval(CI):1.07-1.92,adjusted P value=0.016]and common bile(aOR=1.68,95%CI:1.27-2.23,adjusted P value<0.001)ducts,length of the common hepatic duct(aOR=0.92,95%CI:0.84-0.99,adjusted P value=0.034),and angle of the common bile duct(aOR=0.92,95%CI:0.89–0.95,adjusted P value<0.001).The anatomical features of the extrahepatic bile duct were directly associated with choledocholithiasis risk.Key risk factors include an enlarged diameter of the common hepatic and bile ducts,a shorter length of the common hepatic duct,and a reduced angle of the common bile duct. 展开更多
关键词 Bile ducts EXTRAHEPATIC CHOLEDOCHOLITHIASIS CHOLANGIOPANCREATOGRAPHY Magnetic resonance CHOLANGIOPANCREATOGRAPHY Endoscopic retrograde
下载PDF
经食管三维超声在二尖瓣成形术中的应用 被引量:8
6
作者 洪灿 刘素君 +6 位作者 周佳 田方平 丁正东 冯耀光 龙超众 常帅 刘骞 《中国现代医学杂志》 CAS 2018年第22期80-84,共5页
目的探讨经食管实时三维超声心动图(RT3D-TEE)在二尖瓣成形术中的应用价值。方法 18例拟行二尖瓣成形术的二尖瓣脱垂患者,术前及术后即刻均接受RT3D-TEE检查。术前观察二尖瓣脱垂的三维特征及小叶区域,与外科术中所见对照;术后即刻评估... 目的探讨经食管实时三维超声心动图(RT3D-TEE)在二尖瓣成形术中的应用价值。方法 18例拟行二尖瓣成形术的二尖瓣脱垂患者,术前及术后即刻均接受RT3D-TEE检查。术前观察二尖瓣脱垂的三维特征及小叶区域,与外科术中所见对照;术后即刻评估二尖瓣成形的手术效果,比较手术前后二尖瓣的对合高度、瓣环周长和反流面积。结果 RT3D-TEE显示二尖瓣脱垂的三维图像与外科视野所见高度一致,术前诊断脱垂小叶的敏感性、特异性分别为96.00%、100.00%。18例患者中有2例转行二尖瓣置换术,其余16例成功完成二尖瓣成形术。RT3D-TEE观察术后二尖瓣叶及人工瓣环的形态良好,二尖瓣反流程度明显改善。二尖瓣的对合高度较术前增加,瓣环周长、反流面积较术前减少,差异有统计学意义(t=-13.556,37.789和20.847,均P=0.000)。结论 RT3D-TEE能清晰显示二尖瓣的三维形态,术前准确诊断脱垂小叶及术后即刻评估手术效果,在二尖瓣成形术中发挥重要的作用。 展开更多
关键词 超声心动图 三维 经食管 二尖瓣成形 二尖瓣脱垂
下载PDF
超声内镜引导下无水乙醇注射法与外科手术法治疗良性胰岛素瘤的对比研究 被引量:3
7
作者 蒋艳娟 覃山羽 +10 位作者 姜海行 覃凤燕 刘芷玲 罗佐杰 秦映芬 周嘉 梁瑜祯 梁敏 梁杏欢 陈俊强 覃新干 《中国内镜杂志》 北大核心 2017年第4期8-13,共6页
目的评估超声内镜(EUS)引导下无水乙醇注射法治疗良性胰岛素瘤的疗效与安全性,并与外科手术治疗法相比较。方法回顾性分析2011年4月-2016年2月在广西医科大学第一附属医院经EUS引导下无水乙醇注射法治疗或外科手术法治疗的38例良性胰岛... 目的评估超声内镜(EUS)引导下无水乙醇注射法治疗良性胰岛素瘤的疗效与安全性,并与外科手术治疗法相比较。方法回顾性分析2011年4月-2016年2月在广西医科大学第一附属医院经EUS引导下无水乙醇注射法治疗或外科手术法治疗的38例良性胰岛素瘤临床资料。结果 97.4%(37/38)的患者有典型的Whipple三联征,82.9%(29/35)患者低血糖发作时胰岛素释放指数(I/G)>0.3。术前B超、CT、磁共振成像(MRI)、正电子发射计算机断层显像(PET/CT)和EUS定位诊断胰岛素瘤阳性率分别为50.0%、67.6%、66.7%、75.0%和89.7%。18例行EUS引导下无水乙醇注射治疗(EUS-FNI组),20例行外科手术治疗(外科手术组),EUS-FNI组术后均无并发症发生,外科手术组中40.0%(8/20)患者出现并发症。与外科手术组相比,EUS-FNI组在手术时间、术中出血、术后并发症、术后住院时间和住院总费用上均明显降低(P<0.05)。所有患者均得到随访,EUS-FNI组最后一次无水乙醇注射治疗后所有患者血糖平稳在正常范围;外科手术组20例患者中,90.0%(18/20)患者术后无低血糖症状再发作,监测血糖在正常范围,10.0%(2/20)患者术后低血糖症状发作较术前减少。结论 EUS引导下无水乙醇注射法治疗良性胰岛素瘤安全、有效。与外科手术法相比,具有微创、经济、并发症少和术后恢复快等优势。 展开更多
关键词 胰岛素瘤 超声内镜 细针穿刺 乙醇注射 外科手术
下载PDF
老年慢性阻塞性肺疾病合并呼吸衰竭危险因素分析 被引量:25
8
作者 王文欣 周茄 +1 位作者 张宇 杨春娟 《中国现代医学杂志》 CAS 2018年第31期113-117,共5页
目的探讨老年慢性阻塞性肺疾病(COPD)合并呼吸衰竭的临床流行病学特点、临床症状、生理生化改变,分析引起老年COPD合并呼吸衰竭的原因。方法选取2016年1月-2017年1月天津医院196例老年COPD合并呼吸衰竭患者作为病例组,同期选取202例单... 目的探讨老年慢性阻塞性肺疾病(COPD)合并呼吸衰竭的临床流行病学特点、临床症状、生理生化改变,分析引起老年COPD合并呼吸衰竭的原因。方法选取2016年1月-2017年1月天津医院196例老年COPD合并呼吸衰竭患者作为病例组,同期选取202例单纯老年COPD患者作为对照组,回顾性分析两组患者在住院期间基本临床资料、临床症状和肺功能检测,以及生化检查指标,找出差异进一步进行Logistic回归分析。结果病例组患者平均年龄、体重指数、吸烟史等临床资料与对照组比较,差异无统计学意义(P>0.05);而病例组的颈围与对照组比较,差异有统计学意义(P <0.05),病例组高于对照组;病例组在合并心血管疾病、肾脏疾病、患病时间与对照组比较,差异有统计学意义(P <0.05),病例组高于对照组。咳嗽、咳痰这两个临床常见症状在两组中差异无统计学意义(P>0.05);病例组呼吸困难、COPD合并低蛋白血症、夜间憋醒者与对照组比较,差异有统计学意义(P <0.05),病例组患者例数高于对照组。病例组的FEV1%预计值与对照组比较,差异有统计学意义(P <0.05),病例组低于对照组;Logistic回归分析,发现呼吸困难、夜间憋醒、低蛋白血症、心血管病史、肾脏疾病史及病程时间与老年COPD合并呼吸衰竭和颈围均有相关(P<0.05)。结论对于临床上表现有呼吸困难、夜间憋醒、低蛋白血症并且合并心血管病史、肾脏疾病史、长病程的老年COPD患者应提高警惕,因为此类患者合并呼吸衰竭的可能性极高。 展开更多
关键词 呼吸衰竭 慢性阻塞性肺疾病 LOGISTIC回归分析
下载PDF
圆筒型双Ω定子横向磁通永磁电机建模分析 被引量:3
9
作者 余莉 刘锐 +2 位作者 贾周 印鑫宇 朱淏波 《现代电子技术》 北大核心 2019年第5期100-103,共4页
双Ω型定子横向磁通永磁直线电机在同一个电枢上通过整合两组定子铁心的方式使得其结构更加紧凑,其空间利用率高、效率高、功率密度大。在分析新型双Ω定子横向磁通永磁直线电机的基础上设计了两类圆筒型的双Ω定子横向磁通永磁电机,采... 双Ω型定子横向磁通永磁直线电机在同一个电枢上通过整合两组定子铁心的方式使得其结构更加紧凑,其空间利用率高、效率高、功率密度大。在分析新型双Ω定子横向磁通永磁直线电机的基础上设计了两类圆筒型的双Ω定子横向磁通永磁电机,采用有限元分析方法(FEA)分别对两类电机的气隙磁密波形、反电势、磁链及电磁转矩参数进行比较分析。结果表明:三相结构更加紧凑,适用于对电机体积限制严格、转矩高的场合;单相结构的磁通密度分布、反电势、磁链参数波形更为理想,在电机精度要求较高的场合可选择该结构。 展开更多
关键词 横向磁通 永磁电机 有限元分析 直线电机 功率密度 扭矩
下载PDF
“营改增”的市场反应及其趋势——基于改革进程的事件研究
10
作者 曹越 周佳 《会计论坛》 2020年第1期-,共27页
本文以"营改增"分地区、分行业逐步推进为时间节点,利用事件研究法,全面检验六次"营改增"的整体市场反应及分行业的市场反应,并从税收敏感度、雇佣规模和固定资产密度三个维度分析该市场反应的影响因素。研究发现,... 本文以"营改增"分地区、分行业逐步推进为时间节点,利用事件研究法,全面检验六次"营改增"的整体市场反应及分行业的市场反应,并从税收敏感度、雇佣规模和固定资产密度三个维度分析该市场反应的影响因素。研究发现,整体而言,投资者一直将"营改增"视为利好消息,但不同行业"营改增"的市场反应有差异:投资者对交通运输业"营改增"的反应经历了从"观望"到"利好"的转变,视现代服务业、邮政业、电信业、房地产业与金融业"营改增"为利好消息,视建筑业"营改增"为利空消息,对生活服务业"营改增"则持观望态度。进一步研究发现,税收敏感度越高和雇佣规模越小的公司,累计超额收益率越高,但固定资产密度与累计超额收益率无显著关系。 展开更多
关键词 “营改增” 市场反应 税收敏感度 雇佣规模 固定资产密度
下载PDF
外源γ-氨基丁酸对高温胁迫下番茄幼苗生长、抗氧化酶活性及光合特性的影响 被引量:1
11
作者 史建硕 潘丽佳 +4 位作者 蒋龙刚 贾舟 任燕利 侯升林 王丽英 《华北农学报》 CSCD 北大核心 2023年第S01期188-193,共6页
为探究高温胁迫下不同浓度外源GABA对番茄幼苗干物质积累、根系发育、抗氧化酶活性及光合特性的影响。选用番茄品种粉特利为试材,设置叶面喷施清水(CK)、1 mmol/L GABA(T1)、5 mmol/L GABA(T2)、10 mmol/L GABA(T3)、20 mmol/L GABA(T4)... 为探究高温胁迫下不同浓度外源GABA对番茄幼苗干物质积累、根系发育、抗氧化酶活性及光合特性的影响。选用番茄品种粉特利为试材,设置叶面喷施清水(CK)、1 mmol/L GABA(T1)、5 mmol/L GABA(T2)、10 mmol/L GABA(T3)、20 mmol/L GABA(T4)5个处理。每2 d进行1次喷施,连续喷施2次。然后,将幼苗置于40℃/35℃(昼/夜),14 h(光)/10 h(暗),光强250μmol/(m^(2)·s)条件下,高温胁迫处理7 d。结果表明,与CK相比,叶面喷施10 mmol/L及以下浓度的GABA(T1、T2和T3)显著促进番茄幼苗的生长,其中株高、茎粗、地上部干物质量和壮苗指数分别提高4.96%~6.92%,7.65%~19.26%,29.41%~52.94%和20.00%~26.67%。其中,T2较CK处理,显著提高了根系的总根长、总表面积、总体积和根尖数,增幅分别为23.04%,13.95%,11.76%和18.30%。此外,与CK相比,T2处理会通过增加叶片的(超氧化物歧化酶)SOD、(过氧化物酶)POD和(过氧化氢酶)CAT酶活性(增幅分别为22.58%,51.73%和148.80%),同时降低叶片的相对电导率和丙二醛含量(降幅分别为12.84%和21.89%),从而保证叶片细胞膜结构和功能的完整,进而提高叶片的光合速率、气孔导度和蒸腾速率(增幅分别为81.38%,36.19%,41.26%)。然而,高浓度的GABA(T4)与CK处理的幼苗干物质积累、光合特性及叶片相对电导率差异不显著,甚至会抑制根系的生长发育。综上,叶面喷施适宜浓度的GABA既可通过提高叶片渗透调节能力和抗氧化酶活性,保护叶片细胞膜的完整性,进而缓解高温胁迫对光合作用的抑制,亦会通过促进番茄幼苗干物质积累和根系发育,从而提高番茄幼苗的耐热性。本试验条件下,以5 mmol/L的GABA效果最优。 展开更多
关键词 番茄幼苗 Γ-氨基丁酸 高温胁迫 抗氧化酶活性 光合特性
下载PDF
秸秆还田对石灰性土壤Zn扩散迁移及形态转化的影响 被引量:8
12
作者 陈艳龙 贾舟 +3 位作者 师江澜 刘珂 王少霞 田霄鸿 《土壤学报》 CAS CSCD 北大核心 2018年第3期721-733,共13页
有机碳(特别是活性组分)通过络合、螯合等作用对土壤锌(Zn)的迁移转化起重要作用。目前,作物秸秆还田已经代替传统有机肥,成为中国提高粮田土壤有机碳含量及质量的最主要措施。基于此,采用半扩散池装置通过室内模拟试验探究了秸秆还田... 有机碳(特别是活性组分)通过络合、螯合等作用对土壤锌(Zn)的迁移转化起重要作用。目前,作物秸秆还田已经代替传统有机肥,成为中国提高粮田土壤有机碳含量及质量的最主要措施。基于此,采用半扩散池装置通过室内模拟试验探究了秸秆还田对石灰性土壤有效Zn(二乙三胺五乙酸浸提态Zn,即DTPA-Zn)扩散迁移及Zn形态转化的影响,以期为提高石灰性土壤Zn有效性及移动性,进而改善作物对Zn的吸收利用提供科学依据。结果表明,单独秸秆还田显著提高了土壤有机碳及活性碳组分(如溶解性有机碳(DOC)和富里酸(FA))含量,但对土壤DTPA-Zn的扩散迁移及Zn形态转化影响甚微。单施Zn肥通过提高松结有机态Zn(Lom-Zn)含量及其在全Zn中的分布,显著改善了土壤DTPA-Zn含量及扩散迁移能力;但是,其扩散的DTPA-Zn却主要被限制在非施肥区15 mm以内(45 d),这可能与外源Zn在石灰性土壤上的无效化有关。当秸秆还田与Zn配施时,土壤DTPA-Zn和各形态Zn含量与单施Zn肥相似,但DTPA-Zn的最远扩散距离可达非施肥区20 mm(45 d)处,且累积扩散量和扩散比率均高于单独施Zn。秸秆还田配施Zn肥施肥区土壤活性碳组分(DOC和FA)含量的提升,有效地抑制了外源Zn向无效态组分(残渣态)转化,进而提高了土壤DTPA-Zn的含量及扩散迁移能力。可见,在秸秆还田条件下,土壤施Zn是一种有效提升石灰性土壤有效Zn含量同时兼顾Zn扩散迁移能力的重要措施。 展开更多
关键词 土壤DTPA-Zn 扩散池 Zn分组 腐殖质 活性有机碳
下载PDF
Comparison of transcriptome and metabolome analysis revealed differences in cold resistant metabolic pathways in different apple cultivars under low temperature stress 被引量:6
13
作者 Gongxun Xu Lijie Li +3 位作者 jia zhou Deguo Lyu Deying Zhao Sijun Qin 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第2期183-198,共16页
Freezing injury in winter is an important abiotic stress that seriously affects plant growth and development.Deciduous fruit trees resist freezing injury by inducing dormancy.However,different cultivars of the same sp... Freezing injury in winter is an important abiotic stress that seriously affects plant growth and development.Deciduous fruit trees resist freezing injury by inducing dormancy.However,different cultivars of the same species have different cold resistance strategies.Little is known about the molecular mechanism of apple trees in response to freezing injury during winter dormancy.Therefore,in this study,1-year-old branches of the cold-resistant cultivar‘Hanfu’(HF)and the cold-sensitive cultivar‘Changfuji No.2’(CF)were used to explore their cold resistance through physiological,biochemical,transcriptomics,and metabolomics analyses.Combining physiological and biochemical data,we found that HF had a stronger osmotic regulation ability and antioxidant enzyme activity than CF,as well as stronger cold resistance.The functional enrichment analysis showed that both cultivars were significantly enriched in pathways related to signal transduction,hormone regulation,and sugar metabolism under freezing stress.In addition,the differentially expressed genes(DEGs)encoding galactinol synthase,raffinose synthase,and stachyose synthetase in raffinose family oligosaccharides(RFOs)metabolic pathways were upregulated in HF,and raffinose and stachyose were accumulated,while their contents in CF were lower.HF accumulated 4-aminobutyric acid,spermidine,and ascorbic acid to scavenge reactive oxygen species(ROS).While the contents of oxidized glutathione,vitamin C,glutathione,and spermidine in CF decreased under freezing stress,consequently,the ability to scavenge ROS was low.Furthermore,the transcription factors apetala 2/ethylene responsive factor(AP2/ERF)and WRKY were strongly induced under freezing stress.In summary,the difference in key metabolic components of HF and CF under freezing stress is the major factor affecting their difference in cold resistance.The obtained results deepen our understanding of the cold resistance mechanism in apple trees in response to freezing injury during dormancy. 展开更多
关键词 APPLE Freezing stress Cold resistance Galactinol synthase TRANSCRIPTOME METABOLOME
下载PDF
Influence of increased epicardial adipose tissue volume on 1-year in-stent restenosis in patients who received coronary stent implantation 被引量:6
14
作者 Ying zhou Hua-Wei ZHANG +7 位作者 Feng TIAN Jin-Song CHEN Tian-Wen HAN Ya-Hang TAN jia zhou Tao ZHANG Jing JING Yun-Dai CHEN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第9期768-775,共8页
Background Epicardial adipose tissue (EAT) is significantly associated with the formation and composition of coronary atherosclerotic plaque, cardiac events and the clinical prognosis of coronary heart disease. But,... Background Epicardial adipose tissue (EAT) is significantly associated with the formation and composition of coronary atherosclerotic plaque, cardiac events and the clinical prognosis of coronary heart disease. But, whether increased EAT deposition may affect the incidence of in-stent restenosis (ISR) is currently unclear. This study used coronary computed tomography angiography (CCTA) as a mean to investigate whether increased EAT volume was associated with ISR. Methods A total of 364 patients who underwent 64-slice CCTA examination for the evaluation of suspected coronary artery disease, and subsequently underwent percutaneous coronary intervention (PCI) for the first time, and then accepted coronary angiography (CA) follow-up for ISR examination in one year, were retrospectively included in this study. EAT volume was measured by CCTA examination. CA follow-up was obtained between 9 and 15 months. ISR was defined as 〉 50% kuninal diameter narrowing of the stent segment or peri-stent segment. EAT volume was compared between patients with and without ISR and additional well-known predictors of ISR were compared. Results EAT volume was significantly increased in patients with ISR compared with those without ISR (154.5 ± 74.6 mL vs. 131.0 ± 52.2 mL, P 〈 0.001). The relation between ISR and EAT volume remained significant after adjustment for conventional cardiovascular risk factors and angiographic parameters. Conclusions EAT volume was related with ISR and may provide additional information for future ISR. 展开更多
关键词 Computed tomography Drug-eluting stents Epicardial adipose tissue In-stem restenosis
下载PDF
背靠背Ω定子横向磁通永磁直线电机 被引量:3
15
作者 贾周 杨卫平 +3 位作者 贺伟 余莉 曹永娟 贾红云 《中国电机工程学报》 EI CSCD 北大核心 2022年第21期7964-7971,共8页
在错列式双Ω型定子横向磁通永磁直线电机研究基础上,该文提出背靠背Ω定子横向磁通永磁直线电机,该电机采用背靠背Ω定子配合聚磁结构动子实现电负荷与磁负荷的相互解耦。首先,阐述该电机的单相结构和工作原理并对样机尺寸进行推导。其... 在错列式双Ω型定子横向磁通永磁直线电机研究基础上,该文提出背靠背Ω定子横向磁通永磁直线电机,该电机采用背靠背Ω定子配合聚磁结构动子实现电负荷与磁负荷的相互解耦。首先,阐述该电机的单相结构和工作原理并对样机尺寸进行推导。其次,采用三维有限元方法对电机磁场分布进行分析,对电机磁通密度、电枢反电势及电枢自感等电磁参数进行计算。最后,对三相电机推力和定位力进行仿真和优化。样机实验结果表明,与错列式双Ω型定子电机相比,所提新结构电机的磁通密度、电枢反电势、电机推力和功率密度等指标均得到显著提升。实验结果与仿真数据具有较好的吻合度,验证所提电机结构设计的正确性和可行性。 展开更多
关键词 背靠背Ω定子 有限元法 横向磁通 直线电机
下载PDF
Design of interdigitated transducers for acoustofluidic applications 被引量:2
16
作者 Shuren Song Qi Wang +1 位作者 jia zhou Antoine Riaud 《Nanotechnology and Precision Engineering》 CAS CSCD 2022年第3期36-54,共19页
Interdigitated transducers(IDTs)were originally designed as delay lines for radars.Half a century later,they have found new life as actuators for microfluidic systems.By generating strong acoustic fields,they trigger ... Interdigitated transducers(IDTs)were originally designed as delay lines for radars.Half a century later,they have found new life as actuators for microfluidic systems.By generating strong acoustic fields,they trigger nonlinear effects that enable pumping and mixing of fluids,and moving particles without contact.However,the transition from signal processing to actuators comes with a range of challenges concerning power density and spatial resolution that have spurred exciting developments in solid-state acoustics and especially in IDT design.Assuming some familiarity with acoustofluidics,this paper aims to provide a tutorial for IDT design and characterization for the purpose of acoustofluidic actuation.It is targeted at a diverse audience of researchers in various fields,including fluid mechanics,acoustics,and microelectronics. 展开更多
关键词 Acoustic field Surface acoustic wave TRANSDUCER Finite-element analysis SIMULATION Acoustical properties LAB-ON-A-CHIP Acoustic wave attenuation
下载PDF
Mathematica在化学群论教学中的应用 被引量:4
17
作者 周佳 魏梦娇 《大学化学》 CAS 2022年第6期197-202,共6页
介绍了数学软件Mathematica在高等院校化学课程中群论部分教学的应用。借助Mathematica强大的数学计算和可视化功能,降低了群论理论教学难度,使群论教学内容更加生动。通过形象地展示分子的对称元素以及对称操作,帮助学生更好地理解与... 介绍了数学软件Mathematica在高等院校化学课程中群论部分教学的应用。借助Mathematica强大的数学计算和可视化功能,降低了群论理论教学难度,使群论教学内容更加生动。通过形象地展示分子的对称元素以及对称操作,帮助学生更好地理解与掌握分子的对称性以及对称操作,提升学生对群论课程的学习兴趣,进而提升教学质量。 展开更多
关键词 MATHEMATICA 群论 对称性 变换矩阵
下载PDF
Prioritizing real estate enterprises based on credit risk assessment:an integrated multi‑criteria group decision support framework 被引量:1
18
作者 Zhen‑Song Chen jia zhou +5 位作者 Chen‑Ye Zhu Zhu‑Jun Wang Sheng‑Hua Xiong Rosa M.Rodríguez Luis Martínez Mirosław J.Skibniewski 《Financial Innovation》 2023年第1期2939-2991,共53页
Credit risk assessment involves conducting a fair review and evaluation of an assessed subject’s solvency and creditworthiness.In the context of real estate enterprises,credit risk assessment provides a basis for ban... Credit risk assessment involves conducting a fair review and evaluation of an assessed subject’s solvency and creditworthiness.In the context of real estate enterprises,credit risk assessment provides a basis for banks and other financial institutions to choose suitable investment objects.Additionally,it encourages real estate enterprises to abide by market norms and provide reliable information for the standardized management of the real estate industry.However,Chinese real estate companies are hesitant to disclose their actual operating data due to privacy concerns,making subjective evalu-ation approaches inevitable,occupying important roles in accomplishing Chinese real estate enterprise credit risk assessment tasks.To improve the normative and reliability of credit risk assessment for Chinese real estate enterprises,this study proposes an integrated multi-criteria group decision-making approach.First,a credit risk assessment index for Chinese real estate enterprises is established.Then,the proposed framework combines proportional hesitant fuzzy linguistic term sets and preference ranking organization method for enrichment evaluation II methods.This approach is suitable for processing large amounts of data with high uncertainty,which is often the case in credit risk assessment tasks of Chinese real estate enterprises involving massive subjec-tive evaluation information.Finally,the proposed model is validated through a case study accompanied by sensitivity and comparative analyses to verify its rationality and feasibility.This study contributes to the research on credit assessment for Chinese real estate enterprises and provides a revised paradigm for real estate enterprise credit risk assessment. 展开更多
关键词 Real estate enterprise Credit risk assessment PROMETHEE II Best–worst method Proportional hesitant fuzzy linguistic term sets
下载PDF
Full laparoscopic anatomical liver segment Ⅶ resection with preferred Glissonean pedicle and dorsal hepatic approach 被引量:1
19
作者 jia zhou Ying-Hui Song +5 位作者 Yu-Chen Qi Ou Li Guo-Yi Xia Meng-Jun Mo Chuang Peng Su-Lai Liu 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第5期532-536,共5页
Anatomical liver resection was an option for liver cancer proposed by the Japanese scholar Masatoshi Makuuchi in 1985 [1].Reich et al.performed the first laparoscopic liver resection in1991 [2].The safety and effectiv... Anatomical liver resection was an option for liver cancer proposed by the Japanese scholar Masatoshi Makuuchi in 1985 [1].Reich et al.performed the first laparoscopic liver resection in1991 [2].The safety and effectiveness of laparoscopic anatomical liver resection had been verified in recent years [2-4].However,laparoscopic anatomical segmentⅦliver resection (LAS7) was the most difficult procedure because of complex adjacent structures,difficult exposure,and limited laparoscopic view [3,5]. 展开更多
关键词 RESECTION LAPAROSCOPIC HEPATIC
下载PDF
单分子反应理论的启发式教学实践 被引量:1
20
作者 周佳 魏梦娇 《大学化学》 CAS 2022年第6期34-38,共5页
将启发式教学理念应用到单分子反应理论的教学中。本文针对单分子反应RRKM理论的教学难点,通过在课堂上引入科研实例,再设计问题,一点点启发学生思考,激发课堂讨论,让学生更加容易地理解知识难点,同时提高学生分析问题和解决问题的能力。
关键词 RRKM理论 启发式教学 单分子反应 分子模拟
下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部