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Response of size-fractionated phytoplankton to environmental factors near the Changjiang Estuary 预览
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作者 Li Li Jingyi Cen +1 位作者 Lei Cui Songhui Lu 《海洋学报:英文版》 SCIE CAS CSCD 2019年第1期151-159,共9页
Size-based partitioning of phytoplankton is a useful tool for monitoring key phytoplankton traits, and it provides a better understanding of phytoplankton dynamics. Our aim is to determine the variation in the differe... Size-based partitioning of phytoplankton is a useful tool for monitoring key phytoplankton traits, and it provides a better understanding of phytoplankton dynamics. Our aim is to determine the variation in the different size classes of phytoplankton to the total phytoplankton biomass during the spring and autumn of 2010 and examine the relationship between phytoplankton size structure and environmental variables and zooplankton community structure near the Changjiang Estuary. In the spring, phytoplankton populations were predominantly consisted of nanophytoplankton throughout the study region. In the autumn, picophytoplankton and nanophytoplankton collectively dominated the phytoplankton community. A Pearson correlation analysis highlighted the role of temperature and trophic conditions on the contributions of nanophytoplankton and picophytoplankton. The grazing pressure exerted by mesozooplankton could have played an important role in determining the microphytoplankton community structure. 展开更多
关键词 PHYTOPLANKTON size structure temperature TROPHIC condition seasonal SUCCESSION CHANGJIANG Estuary
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Seasonal variation in surface ozone and its regional characteristics at global atmosphere watch stations in China
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作者 Ningwei Liu Weili Lin +2 位作者 Jianzhong Ma Wanyun Xu Xiaobin Xu 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期291-302,共12页
We investigated the seasonal and spatial ozone variations in China by using three-year surface ozone observation data from the six Chinese Global Atmosphere Watch(GAW)stations and tropospheric column ozone data from s... We investigated the seasonal and spatial ozone variations in China by using three-year surface ozone observation data from the six Chinese Global Atmosphere Watch(GAW)stations and tropospheric column ozone data from satellite retrieval over the period2010–2012. It is shown that the seasonal ozone variations at these GAW stations are rather different, particularly between the western and eastern locations. Compared with western China, eastern China has lower background ozone levels. However, the Asian summer monsoon(ASM) can transport photochemical pollutants from the southern to the northern areas in eastern China, leading to a northward gradual enhancement of background ozone levels at the eastern GAW stations. Over China, the tropospheric column ozone densities peak during spring and summer in the areas that are directly and/or indirectly affected by the ASM, and the peak time lags from the south to the north in eastern China. We also investigated the regional representativeness of seasonal variations of ozone at the six Chinese GAW stations using the yearly maximum tropospheric column month as indicator.The results show that the seasonal variation characteristics of ozone revealed by the Chinese GAW stations are typical, with each station having a considerable large surrounding area with the ozone maximum occurring at the same month. Ozone variations at the GAW stations are influenced by many complex factors and their regional representativeness needs to be investigated further in a broader sense. 展开更多
关键词 Surface OZONE TROPOSPHERIC OZONE COLUMN GAW STATIONS SEASONAL variations Regional REPRESENTATIVENESS
鼻腔黏膜激发试验的临床应用及研究进展
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作者 肖浩 孟娟 +1 位作者 张虹婷 刘世喜 《中国耳鼻咽喉头颈外科》 CSCD 2019年第2期112-116,共5页
鼻腔黏膜激发试验(nasal provocation testing,NPT)是目前国际公认的诊断变应性鼻炎变应原的'金标准',并广泛应用于评估治疗药物的有效性以及鼻对变应原刺激引发的病理生理学机制研究,但其临床应用仍存在诸多分歧。我国仅有少... 鼻腔黏膜激发试验(nasal provocation testing,NPT)是目前国际公认的诊断变应性鼻炎变应原的'金标准',并广泛应用于评估治疗药物的有效性以及鼻对变应原刺激引发的病理生理学机制研究,但其临床应用仍存在诸多分歧。我国仅有少数相关研究,尚未常规临床应用。本文就NPT适应证及禁忌证、检查前准备及注意事项、操作步骤、评估方法、诊断标准等进行综述,以提高医务工作者对NPT的认识水平。 展开更多
关键词 鼻激发试验 鼻炎 变应性 常年性 鼻炎 变应性 季节性 诊断技术和方法 主观评分 客观评估
盘锦地区过敏性鼻炎患者临床特征调查
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作者 李全胜 郑铭 +1 位作者 王向东 张罗 《中国耳鼻咽喉头颈外科》 CSCD 2019年第3期150-154,共5页
目的 调查盘锦地区过敏性鼻炎(AR)确诊患者的症状特点、治疗情况、伴发疾病以及致敏变应原特征。方法 以2017年3月~2018年2月到盘锦市中心医院耳鼻咽喉科就诊的经血清特异性IgE确诊的AR患者作为研究入组对象,借助专门设计的问卷详尽收... 目的 调查盘锦地区过敏性鼻炎(AR)确诊患者的症状特点、治疗情况、伴发疾病以及致敏变应原特征。方法 以2017年3月~2018年2月到盘锦市中心医院耳鼻咽喉科就诊的经血清特异性IgE确诊的AR患者作为研究入组对象,借助专门设计的问卷详尽收集患者的病史资料。结果共入组613例AR确诊患者,35岁之前男性患者数量超过女性,35岁以后女性患者更多;46%患者在8月和9月集中就诊;根据症状和持续时间分类,轻度间歇性AR 15.0%,轻度持续性AR 14.7%,中重度间歇性AR 18.1%,中重度持续性AR 52.2%;轻度间歇性AR患者很少使用药物治疗(59.8%),中重度持续性AR比例最低(30.6%),跟前者相比,后者常常会在有症状时使用药物(49.7% vs 29.3%),各亚型AR患者药物使用的情况存在统计学差异(χ^2=29.09,P<0.01);症状自报率:喷嚏77.0%,鼻塞59.1%,清水涕53.5%,鼻痒49.6%,眼痒48.0%,溢泪31.8%。鼻塞是持续性AR患者的常见症状(χ^2=14.39,P <0.01),喷嚏和鼻痒症状更多见于间歇性AR患者(χ^2=27.15,P <0.01;χ^2=9.03,P =0.03)。结论 全面了解盘锦地区AR门诊患者的临床特征,为未来的预防和诊治制定有效的临床决策提供科学依据。 展开更多
关键词 鼻炎 变应性 季节性 常年性 体征和症状 伴发疾病
花粉症患者伴发口腔过敏综合征的临床特征及危险因素分析 预览
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作者 王晓艳 李晓荣 +2 位作者 庄严 石海云 王学艳 《重庆医学》 CAS 2019年第2期194-197,共4页
目的探讨花粉症患者伴发口腔过敏综合征(OAS)的临床特征及危险因素。方法205例花粉症患者纳入研究,接受面对面问卷调查并进行过敏原皮肤点刺试验(SPT),进行统计分析。结果花粉症患者中OAS发病率为27.3%(56/205)。OAS组出现呼吸道症状的... 目的探讨花粉症患者伴发口腔过敏综合征(OAS)的临床特征及危险因素。方法205例花粉症患者纳入研究,接受面对面问卷调查并进行过敏原皮肤点刺试验(SPT),进行统计分析。结果花粉症患者中OAS发病率为27.3%(56/205)。OAS组出现呼吸道症状的概率显著高于非OAS组(33.9%vs.16.1%,P=0.005),OAS组由鼻部进展为眼部症状的平均年限为(0.88±0.25)年,显著低于非OAS组[(1.57±0.35)年,P=0.037]。OAS组生活质量评分为(3.54±0.12)分,显著高于非OAS组[(3.19±0.06)分,P=0.007]。OAS组共自报111次食物过敏原。最常见的致敏食物依次为苹果(25.2%)、桃子(17.1%)。结论OAS患者更易出现呼吸道受累,生活质量更易受到影响。 展开更多
关键词 鼻炎 变应性 季节性 口腔过敏综合征 食物过敏 危险因素 疾病病程
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过氧化物酶体增殖物激活受体γ激动剂对小鼠变应性鼻炎治疗的作用与机制研究
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作者 姜婷婷 李欣倩 +2 位作者 朱静静 闫勇 吴曙辉 《中国耳鼻咽喉头颈外科》 CSCD 2019年第2期79-83,共5页
目的探讨过氧化物酶体增殖物激活受体(peroxisome proliferators-actived receptor,PPAR)γ激动剂对小鼠变应性鼻炎的治疗作用及机制。方法采用卵清蛋白(OVA)建立变应性鼻炎小鼠模型,观察吡格列酮(PIO)对变应性鼻炎症状的改善;取鼻腔组... 目的探讨过氧化物酶体增殖物激活受体(peroxisome proliferators-actived receptor,PPAR)γ激动剂对小鼠变应性鼻炎的治疗作用及机制。方法采用卵清蛋白(OVA)建立变应性鼻炎小鼠模型,观察吡格列酮(PIO)对变应性鼻炎症状的改善;取鼻腔组织行HE染色,采用real time PCR检测脾脏Foxp3、T-bet、GATA-3 mRNA表达;流式细胞仪检测脾脏中CD4~+Foxp3~+T细胞含量。结果小鼠变应性鼻炎组(AR组)喷嚏和搔鼻频率明显高于对照组(control组),经PIO治疗后症状得以改善;AR组小鼠鼻黏膜上皮连续性破坏,黏膜下大量炎症细胞浸润;PIO治疗后炎症细胞浸润明显减少,同时上皮完整性修复良好;PIO组Foxp3 mRNA表达高于AR组(P<0.001),GATA-3则较AR组明显降低(P<0.001),而T-bet无统计学差异;AR组CD4~+Foxp3~+T细胞含量(4.43%±0.25%)较control组(5.19%±0.39%)降低(P<0.001),PIO治疗后CD4~+Foxp3~+T细胞含量(6.35%±0.37%)高于control组及A R组。结论 PPA Rγ激动剂能够有效缓解小鼠鼻过敏症状,调节Th1/Th2平衡;PPARγ激动剂可能是通过促进Foxp3表达,进而扩增调节性T细胞达到治疗变应性鼻炎的作用。 展开更多
关键词 鼻炎 变应性 常年性 鼻炎 变应性 季节性 过氧化物酶体增殖物激活受体 叉头转录因子类 T淋巴细胞 Th1-Th2平衡
滨蒿内酯对实验性变应性鼻炎大鼠维甲酸相关孤儿核受体γt及相关因子表达的影响
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作者 王珍 成丽兰 +1 位作者 章诗富 梁耕田 《中国耳鼻咽喉头颈外科》 CSCD 2019年第2期84-87,共4页
目的探讨滨蒿内酯(scoparone,Sco)对实验性变应性鼻炎大鼠的行为、病理,血清中IL-17、IL-23及鼻黏膜组织中维甲酸相关孤儿核受体(retinoic acidrelated orphan receptor gamma t,RORγt)、白细胞介素17(IL-17)、IL-23 mRNA含量的影响。... 目的探讨滨蒿内酯(scoparone,Sco)对实验性变应性鼻炎大鼠的行为、病理,血清中IL-17、IL-23及鼻黏膜组织中维甲酸相关孤儿核受体(retinoic acidrelated orphan receptor gamma t,RORγt)、白细胞介素17(IL-17)、IL-23 mRNA含量的影响。方法构建动物模型,分为正常对照组(NC组)、变应性鼻炎组(AR组)、滨蒿内酯组(Sco组)和地塞米松组(Dxm组),对大鼠症状进行评分,HE染色鼻黏膜,ELISA法检测血清中IL-17、IL-23含量,RT-PCR检测鼻黏膜组织中RORγt、IL-17及IL-23 mRNA表达。结果实验组经滨蒿内酯治疗后症状及炎症病理缓解。Sco组和Dxm组血清IL-17、IL-23较NC组稍高。AR组大鼠RORγt、IL-17及IL-23 mRNA含量均显著高于其他三组。Sco组和Dxm组RORγt、IL-17及IL-23 mRNA较NC组稍高。结论 Sco对大鼠变应性鼻炎的过敏症状具有明显的抑制或消除作用,能降低疾病的严重程度和炎症反应。 展开更多
关键词 鼻炎 变应性 常年性 鼻炎 变应性 季节性 孤儿核受体类 白细胞介素17 白细胞介素23 滨蒿内酯
枸地氯雷他定片与氯雷他定分散片治疗过敏性鼻炎的疗效比较
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作者 徐雪芬 王海哨 胡定国 《中国基层医药》 CAS 2019年第3期345-348,共4页
目的比较枸地氯雷他定片与氯雷他定分散片治疗过敏性鼻炎的疗效、不良反应及其对白三烯B4(LTB4)、白细胞介素4(IL-4)、IL-10及γ-干扰素(INF-γ)的影响。方法选取苍南县第二人民医院2015年6月至2016年6月收治的过敏性鼻炎患者110例为研... 目的比较枸地氯雷他定片与氯雷他定分散片治疗过敏性鼻炎的疗效、不良反应及其对白三烯B4(LTB4)、白细胞介素4(IL-4)、IL-10及γ-干扰素(INF-γ)的影响。方法选取苍南县第二人民医院2015年6月至2016年6月收治的过敏性鼻炎患者110例为研究对象,采用随机数字表法分为对照组、观察组各55例。对照组采用氯雷他定治疗,观察组采用枸地氯雷他定分散片治疗,两组疗程均为14d。比较两组临床疗效、不良反应及LTB4、IL-4、IL-10、INF-γ水平变化。结果观察组总有效率为94.5%(52/55),显著高于对照组的80.0%(44/55)(χ2=6.310,P<0.05)。观察组不良反应发生率为16.4%(9/55),对照组为20.0%(11/55),两组差异无统计学意义(P>0.05)。治疗前,两组LTB4、IL-4、IL-10、INF-γ水平差异均无统计学意义(均P>0.05);治疗14d后,观察组LTB4、IL-4、IL-10、INF-γ分别为(67.74±10.15)ng/L、(52.37±5.12)μg/L、(81.26±11.78)μg/L、(94.47±7.87)μg/L,对照组分别为(80.32±9.97)ng/L、(62.95±5.45)μg/L、(96.32±11.57)μg/L、(86.74±7.63)μg/L,两组差异均有统计学意义(t=7.124、5.262、4.654、3.718,均P<0.05)。结论枸地氯雷他定片和氯雷他定分散片均能有效治疗过敏性鼻炎,降低LTB4、IL-4、IL-10水平,升高INF-γ水平,且不良反应较少,但枸地氯雷他定疗效更显著。 展开更多
关键词 鼻炎 变应性 季节性 枸地氯雷他定片 氯雷他定分散片 白三烯B4 白细胞介素4 白细胞介素10 干扰素Γ
Seasonal characteristics and formation mechanism of the thermohaline structure of mesoscale eddy in the South China Sea 预览
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作者 Yongcan Zu Shuangwen Sun +4 位作者 Wei Zhao Peiliang Li Baochao Liu Yue Fang Azizan Abu Samah 《海洋学报:英文版》 SCIE CAS CSCD 2019年第4期29-38,共10页
The seasonal characteristics and formation mechanism of the thermohaline structure of mesoscale eddy in the South China Sea are investigated using the latest eddy dataset and ARMOR3D data.Eddy-centric composites revea... The seasonal characteristics and formation mechanism of the thermohaline structure of mesoscale eddy in the South China Sea are investigated using the latest eddy dataset and ARMOR3D data.Eddy-centric composites reveal that the horizontal distribution of temperature anomaly associated with eddy in winter is more of a dipole pattern in upper 50 m and tends to be centrosymmetric below 50 m,while in summer the distribution pattern is centrosymmetric in the entire water column.The horizontal distribution of eddy-induced salinity anomaly exhibits similar seasonal characteristics,except that the asymmetry of the salinity anomaly is weaker.The vertical distribution of temperature anomaly associated with eddy shows a monolayer structure,while the salinity anomaly demonstrates a triple-layer structure.Further analysis indicates that the vertical distribution of the anomalies is related to the vertical structure of background temperature and salinity fields,and the asymmetry of the anomalies in upper 50 m is mainly caused by the horizontal advection of background temperature and salinity. 展开更多
关键词 MESOSCALE EDDY THERMOHALINE structure SEASONAL CHARACTERISTICS South China Sea
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Seasonal variation of water transport through the Karimata Strait 预览
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作者 Yan Wang Tengfei Xu +5 位作者 Shujiang Li R.Dwi Susanto Teguh Agustiadi Mukti Trenggono Wei Tan Zexun Wei 《海洋学报:英文版》 SCIE CAS CSCD 2019年第4期47-57,共11页
Four trawl-resistant bottom mounts,with acoustic Doppler current profilers(ADCPs)embedded,were deployed in the Karimata Strait from November 2008 to June 2015 as part of the South China Sea-Indonesian Seas Transport/E... Four trawl-resistant bottom mounts,with acoustic Doppler current profilers(ADCPs)embedded,were deployed in the Karimata Strait from November 2008 to June 2015 as part of the South China Sea-Indonesian Seas Transport/Exchange and Impact on Seasonal Fish Migration(SITE)Program,to estimate the volume and property transport between the South China Sea and Indonesian seas via the strait.The observed current data reveal that the volume transport through the Karimata Strait exhibits significant seasonal variation.The winteraveraged(from December to February)transport is–1.99 Sv(1 Sv=1×106 m3/s),while in the boreal summer(from June to August),the average transport is 0.69 Sv.Moreover,the average transport from January 2009 to December 2014 is–0.74 Sv(the positive/negative value indicates northward/southward transport).May and September are the transition period.In May,the currents in the Karimata Strait turn northward,consistent with the local monsoon.In September,the southeasterly trade wind is still present over the strait,driving surface water northward,whereas the bottom flow reverses direction,possibly because of the pressure gradient across the strait from north to south. 展开更多
关键词 Karimata STRAIT water transport SEASONAL VARIATION SOUTH China SEA THROUGHFLOW
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Numerical Study on Seasonal Transportation of the Suspended Sediments in the Modern Yellow River Mouth Effected by the Artificial Water and Sediment Regulation 预览
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作者 WANG Nan QIAO Lulu +5 位作者 LI Guangxue ZHONG Yi SONG Dehai DING Dong GAO Fei JI Fengying 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第1期20-30,共11页
Since 2002,an artificial water and sediment regulation(AWSR)has been carried out,which largely reduced water and sediment discharged from the Yellow River into the Bohai Sea.Although the sediment transport in the Yell... Since 2002,an artificial water and sediment regulation(AWSR)has been carried out,which largely reduced water and sediment discharged from the Yellow River into the Bohai Sea.Although the sediment transport in the Yellow River Mouth(YRM)has been observed and modeled intensively since AWSR,but preferentially for the non-storm conditions.In this study,a three-dimensional current-wave-sediment coupled model,DHI-MIKE numerical model,was used to examine the seasonal suspended-sediment transport in the YRM after the AWSR.Results show that the seasonal distribution of suspended-sediments in the YRM is dominated by wind and wave rather than river input.The major transport pathway of suspended-sediments is from the western Laizhou Bay to the Bohai Strait during the winter monsoon,especially in storm events.In addition,about 66%of the river sediments deposit within 30km of the YRM,which is smaller than previous estimations.It suggests that the YRM has been eroded in recent decades. 展开更多
关键词 YELLOW River MOUTH artificial water and SEDIMENT regulation MIKE suspended-sediment transport SEASONAL variation
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苏州国内游客流量的季节性预测模型 预览
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作者 李明 《温州职业技术学院学报》 2019年第1期56-59,共4页
游客流量具有明显的非线性和季节性特征,掌握游客流量的动态反应,有利于合理调度和配置资源。通过对数据进行移动平均“中心化”预处理,求解移动平均比率和同月平均比率,剔除复杂经济现象中多因素的影响,考虑季节变动因素的影响,再配合... 游客流量具有明显的非线性和季节性特征,掌握游客流量的动态反应,有利于合理调度和配置资源。通过对数据进行移动平均“中心化”预处理,求解移动平均比率和同月平均比率,剔除复杂经济现象中多因素的影响,考虑季节变动因素的影响,再配合线性回归方程,得出季节性预测值。季节性预测模型求解简单,精度高,较好地拟合了情况复杂且非线性和季节性较强的经济现象,为政府系统调度和合理配置资源提供了参考。 展开更多
关键词 苏州 游客流量 季节性 预测模型
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变应性鼻炎未控制率及其相关因素分析
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作者 陈浩 胡红玲 +4 位作者 宋成 刘晓帆 尹雯 李雪英 胡轶 《中国耳鼻咽喉头颈外科》 CSCD 2019年第1期37-41,共5页
目的 采用变应性鼻炎控制测试问卷评估变应性鼻炎的控制水平,了解变应性鼻炎的未控制率及相关因素。方法 选择门诊就诊的变应性鼻炎患者,并依照《变应性鼻炎及其对哮喘的影响》指南给予规范化的治疗2周后,对患者进行电话随访,比较治疗... 目的 采用变应性鼻炎控制测试问卷评估变应性鼻炎的控制水平,了解变应性鼻炎的未控制率及相关因素。方法 选择门诊就诊的变应性鼻炎患者,并依照《变应性鼻炎及其对哮喘的影响》指南给予规范化的治疗2周后,对患者进行电话随访,比较治疗前后的症状以及对生活质量的影响,并通过变应性鼻炎控制测试评估治疗前、后变应性鼻炎的控制水平,获取变应性鼻炎未控制率及其相关因素。结果 最终纳入134例变应性鼻炎患者,95%为中重度变应性鼻炎,经过2周的治疗,变应性鼻炎患者症状以及生活质量均得到明显改善(P<0.001)。但仍有超过1/4的患者病情未控制,未控制的变应性鼻炎患者体重值较高(P<0.001),多数人吸烟(4.0%vs 17.1%,P=0.02),常有耳鼻喉或上呼吸道感染史和/或最近12个月内由感染导致的抗生素摄入史(40.4%vs 62.9%,P=0.022)和嗅觉紊乱(10.1%vs 25.7%,P=0.044)。结论 经过治疗后变应性鼻炎未控制率为26.1%,吸烟和鼻部感染是未控制变应性鼻炎的危险因素。 展开更多
关键词 鼻炎 变应性 常年性 鼻炎 变应性 季节性 生活质量 危险因素 自我评估
DIURNAL VARIATION OF GLOBAL PRECIPITATION:AN ANALYSIS OF CMORPH DATA
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作者 邢书强 李小凡 《热带气象学报:英文版》 SCIE 2019年第1期45-53,共9页
In this study, the observed CMORPH precipitation data from 1998 to 2015 are used to analyze diurnal variation of global precipitation. The results reveal that the strong diurnal signals of precipitation occur over equ... In this study, the observed CMORPH precipitation data from 1998 to 2015 are used to analyze diurnal variation of global precipitation. The results reveal that the strong diurnal signals of precipitation occur over equatorial continental areas where the annual precipitation centers are located. The phase of diurnal variation of global precipitation reveals a distinct land-sea contrast with nocturnal peaks at sea and afternoon maxima over continents. The analysis of six selected area reveals that precipitation peak over equatorial land areas occur in afternoon and maximum diurnal signals appear in autumn or winter. Eastern equatorial Intertropical Convergence Zone(ITCZ) barely shows diurnal signals in the entire year. Precipitation over Sichuan Basin and northwestern Pacific shows nocturnal peak and the maximum diurnal amplitude in summer. Precipitation over coastal areas off eastern China shows an afternoon peak and the largest diurnal amplitude in summer. 展开更多
关键词 GLOBAL PRECIPITATION DIURNAL VARIATION CMORPH DATA SEASONAL impact
Seasonal prediction skills of FIO-ESM for North Pacific sea surface temperature and precipitation 预览
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作者 Yiding Zhao Xunqiang Yin +1 位作者 Yajuan Song Fangli Qiao 《海洋学报:英文版》 SCIE CAS CSCD 2019年第1期5-12,共8页
The seasonal prediction of sea surface temperature (SST) and precipitation in the North Pacific based on the hindcast results of The First Institute of Oceanography Earth System Model (FIO-ESM) is assessed in this stu... The seasonal prediction of sea surface temperature (SST) and precipitation in the North Pacific based on the hindcast results of The First Institute of Oceanography Earth System Model (FIO-ESM) is assessed in this study. The Ensemble Adjusted Kalman Filter assimilation scheme is used to generate initial conditions, which are shown to be reliable by comparison with the observations. Based on this comparison, we analyze the FIO-ESM 6-month hindcast results starting from each month of 1993–2013. The model exhibits high SST prediction skills over most of the North Pacific for two seasons in advance. Furthermore, it remains skillful at long lead times for midlatitudes. The reliable prediction of SST can transfer fairly well to precipitation prediction via air-sea interactions. The average skill of the North Pacific variability (NPV) index from 1 to 6 months lead is as high as 0.72 (0.55) when El Ni?o-Southern Oscillation and NPV are in phase (out of phase) at initial conditions. The prediction skill of the NPV index of FIO-ESM is improved by 11.6%(23.6%) over the Climate Forecast System, Version 2. For seasonal dependence, the skill of FIO-ESM is higher than the skill of persistence prediction in the later period of prediction. 展开更多
关键词 SEASONAL prediction NORTH PACIFIC sea surface temperature precipitation FIO-ESM climate model
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艾蒿花粉过敏患者呼出一氧化氮及肺功能相关性研究
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作者 邵婵 何雪梅 魏庆宇 《中国耳鼻咽喉头颈外科》 CSCD 2019年第1期45-47,共3页
目的 了解在艾蒿过敏患者中,呼出一氧化氮(fractional exhale nitric oxide,FeNO)与肺功能是否具有相关性,病程、鼻炎评分与FeNO和肺功能是否具有相关性。方法 对2018年8~9月间就诊的88例艾蒿花粉过敏患者的FeNO和肺功能结果进行统计分... 目的 了解在艾蒿过敏患者中,呼出一氧化氮(fractional exhale nitric oxide,FeNO)与肺功能是否具有相关性,病程、鼻炎评分与FeNO和肺功能是否具有相关性。方法 对2018年8~9月间就诊的88例艾蒿花粉过敏患者的FeNO和肺功能结果进行统计分析。结果 病程﹤5年的患者与病程≥9年的患者相比,FeNO和第1秒用力呼气容积占预计值百分比(FEV1%)差异具有统计学意义(P=0.004,P=0.032),且随着病程的延长FeNO也相应增高,而FEV1%则逐渐下降。FeNO与FEF25%-75%占预计值百分比(FEF25%-75%pred)、FEV1%呈负相关,而与FEV1占预计值百分比(FEV1%pred)无相关性。鼻炎评分与FeNO呈正相关;与FEV1%pred、FEV1%、FEF25%-75%pred无相关性。结论随着艾蒿过敏患者病情进展,其气流受限的几率也相应增大;FeNO在一定程度上可以早期预测气道功能的改变,能够作为哮喘预测的监测指标;FeNO值可以反应出机体炎症程度,可用于变应性鼻炎患者病情严重程度的辅助诊断。 展开更多
关键词 鼻炎 变应性 季节性 蒿属 一氧化氮 呼吸功能试验
PM2.5-bound polycyclic aromatic hydrocarbons(PAHs) in Beijing:Seasonal variations,sources,and risk assessment
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作者 Baihuan Feng Lijuan Li +8 位作者 Hongbing Xu Tong Wang Rongshan Wu Jie Chen Yi Zhang Shuo Liu Steven Sai Hang Ho Junji Cao Wei Huang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期11-19,共9页
Polycyclic aromatic hydrocarbons(PAHs) have been of health concern due to its carcinogenesis and mutagenesis. In this study, we aimed to assess the variations, sources, and lifetime excessive cancer risk(ECR) attribut... Polycyclic aromatic hydrocarbons(PAHs) have been of health concern due to its carcinogenesis and mutagenesis. In this study, we aimed to assess the variations, sources, and lifetime excessive cancer risk(ECR) attributable to PAHs bound to ambient particulate matters with aerodynamic diameter less than 2.5 μm(PM2.5) in metropolitan Beijing, China. We collected24-hour integrated PM2.5 samples on daily basis between November 2014 and June 2015 across both central heating(cold months) and non-heating(warm months) seasons, and further analyzed the PAH components in these daily PM2.5 samples. Our results showed that total concentrations of PM2.5-bound PAHs varied between(88.6 ± 75.4) ng/m3 in the cold months and(11.0 ± 5.9) ng/m3 in the warm months. Benzo[a]pyrene(Ba P), the carcinogenic marker of PAHs,averaged at 5.7 and 0.4 ng/m3 in the cold and warm months, respectively. Source apportionment analyses illustrated that gasoline, biomass burning, diesel, coal combustion and cooking were the major contributors, accounting for 12.9%, 17.8%, 24.7%, 24.3% and 6.4% of PM2.5-bound PAHs, respectively. The BaP equivalent lifetime ECR from inhalation of PM2.5-bound PAHs was 16.2 cases per million habitants. Our results suggested that ambient particulate reduction from energy reconstruction and adaption of clean fuels would result in reductions PM2.5-bound PAHs and its associated cancer risks. However, as only particulate phased PAHs was analyzed in the present study, the concentration of ambient PAHs could be underestimated. 展开更多
关键词 PM2.5 PAHS SEASONAL variation SOURCES Cancer risk assessment
新疆羊肉价格波动分析 预览
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作者 鲁云峰 李捷 +2 位作者 王惠 许承云 杨志 《草食家畜》 2019年第1期1-8,28共9页
为分析新疆羊肉价格的季节波动规律、周期和未来走势,对新疆15个地区2008年1月-2018年7月羊肉价格月度数据进行均值处理。运用ADF、AF、Mann-Kendall检验方法对数据进行平稳性、季节性、趋势性检验。运用X-12季节调整法分析新疆羊肉价... 为分析新疆羊肉价格的季节波动规律、周期和未来走势,对新疆15个地区2008年1月-2018年7月羊肉价格月度数据进行均值处理。运用ADF、AF、Mann-Kendall检验方法对数据进行平稳性、季节性、趋势性检验。运用X-12季节调整法分析新疆羊肉价格的季节波动,运用HP滤波法分析新疆羊肉价格进行价格周期确定,运用Holt-Winters季节模型对新疆羊肉价格进行短期预测。研究发现:(1)新疆羊肉价格具有季节性,趋势性波动特征。(2)数据期间内经历了3个半的价格周期,目前处于上涨阶段,未来下半年会有一个下跌过程。应完善新疆羊肉价格形成体系和市场价格风险的监测预警机制,“烫平”价格波动。 展开更多
关键词 新疆 羊肉价格 季节性 周期 预测
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广州市成人变应性鼻炎环境危险因素分析 预览
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作者 郭宏 黄嘉韵 +1 位作者 刘森平 肖洁 《中国现代医学杂志》 CAS 2019年第6期48-52,共5页
目的观察广州市变应性鼻炎(AR)患者的居住环境和饮食习惯中可能的危险因素,为AR的防治提供建议和指导。方法选取2014年11月—2018年7月于广东省第二中医院采用过敏原检测并确诊为AR的1096例患者作为研究对象,进行问卷调查收集资料,并将... 目的观察广州市变应性鼻炎(AR)患者的居住环境和饮食习惯中可能的危险因素,为AR的防治提供建议和指导。方法选取2014年11月—2018年7月于广东省第二中医院采用过敏原检测并确诊为AR的1096例患者作为研究对象,进行问卷调查收集资料,并将同期健康体检人群作对照,分析成人AR的环境危险因素。结果天冷、风大、潮湿、气压低、春季和秋季是AR发病的危险因素(P<0.05)。屋尘螨、粉尘螨是占比最高的过敏原,占40.51%,说明环境对AR具有决定性作用。屋尘螨、粉尘螨、点青霉分枝孢霉、烟曲霉、交链孢菌、潮湿时加重、风大时加重、天冷时加重及气压低时加重均有较高的AR患病风险(P<0.05)。结论居住环境在AR的发生中起重要作用,应加强对家庭居住环境的清洁卫生,尽量降低空气中尘螨密度,并注意合理饮食结构,以降低过敏性疾病的发生率。 展开更多
关键词 鼻炎 变应性 季节性 环境因素诱发疾病 危险因素
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The seasonal variation of the North Pacific Meridional Overturning Circulation heat transport 预览
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作者 LIU Hongwei ZHANG Qilong +2 位作者 PANG Chongguang DUAN Yongliang XU Jianping 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第2期423-433,共11页
Based on the 50-year Simple Ocean Data Assimilation (SODA) reanalysis data, we investigated the basic characteristics and seasonal changes of the meridional heat transport carried by the North Pacific Meridional Overt... Based on the 50-year Simple Ocean Data Assimilation (SODA) reanalysis data, we investigated the basic characteristics and seasonal changes of the meridional heat transport carried by the North Pacific Meridional Overturning Circulation. And we also examined the dynamical and thermodynamic mechanisms responsible for these heat transport variability at the seasonal time scale. Among four cells, the tropical cell (TC) is strongest with a northward heat transport (NHT) of (1.75±0.30) PW (1 PW=1.0×10^15 W) and a southward heat transport (SHT) of (-1.69±0.55) PW, the subtropical cell (STC) is second with a NHT of (0.71±0.65) PW and SHT of (-0.63±0.53) PW, the deep tropical cell (DTC) is third with a NHT of (0.18±0.03) PW and SHT of (-0.18±0.11) PW, while the subpolar cell (SPC) is weakest with a NHT of (0.09±0.05) PW and SHT of (-0.07±0.09) PW. These four cells all have diff erent seasonal changes in their NHT and SHT. Of all, the TC has stronger change in its SHT than in its NHT, so do both the DTC and SPC, but the seasonal change in the STC SHT is weaker than that in its NHT. Therefore, their dynamical and thermodynamic mechanisms are diff erent each other. The local zonal wind stress and net surface heat flux are mainly responsible for the seasonal changes in the TC and STC NHTs and SPC SHT, while the local thermocline circulations and sea temperature are primarily responsible for the seasonal changes of the TC, STC and DTC SHTs and SPC NHT. 展开更多
关键词 MERIDIONAL OVERTURNING CIRCULATION heat transport NORTH PACIFIC SEASONAL variation
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