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Study on the Changes of Physiological Indexes of Water Spinach in Eutrophication Water 被引量:1
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作者 李艳蔷 李兆华 +2 位作者 姜应和 宛晶 赵丽娅 《Agricultural Science & Technology》 CAS 2010年第11期73-76,共4页
[Objective] Effect of hypoxic water culture on physiological characteristic of water spinach and its hypoxia tolerance were studied.[Method] Water spinach was planted in soil and eutrophication water by means of float... [Objective] Effect of hypoxic water culture on physiological characteristic of water spinach and its hypoxia tolerance were studied.[Method] Water spinach was planted in soil and eutrophication water by means of floating bed,respectively,and the change of physiological indexes including chlorophyll,proline(Pro),malondialdehyde(MDA),soluble sugar and soluble protein in water spinach leaves at mature stage was researched,while the hypoxia tolerance of water spinach and the effect of plant density on water spinach growth were discussed in our paper.[Result] In the hypoxic eutrophication water,the content of total chlorophyll,malondialdehyde,soluble sugar and soluble protein in water spinach leaves was lower than that of soil culture,with higher proline content,which showed that water spinach had better tolerance to hypoxic eutrophication water;the higher the plant density,the lower the chlorophyll content in water spinach leaves,and there was no significant effect of plant density on proline and malondialdehyde content,while soluble protein content was higher under high plant density.[Conclusion] The best plant density of water spinach was 66 plants per floating bed with the area of 2 m2,which could provide theoretical basis for the application of water spinach in floating bed. 展开更多
关键词 Water spinach eutrophication water Plant density Physiological index
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Assessment of Water Quality in High-Pressure Peruvian Anthropic Sectors of Lake Titicaca Using a Calibrated Index
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作者 Stive Flores-Gómez Adilson Ben Da Costa Eduardo A. Lobo 《Journal of Geoscience and Environment Protection》 2024年第8期97-114,共18页
The world’s lakes are in the process of degradation, with loss of water quality as a result of anthropic influences. This research aimed to evaluate water quality in high-pressure Peruvian anthropic sectors of Lake T... The world’s lakes are in the process of degradation, with loss of water quality as a result of anthropic influences. This research aimed to evaluate water quality in high-pressure Peruvian anthropic sectors of Lake Titicaca using a calibrated index. The study considered ten important bays with influence from urban sectors. In each bay, surface waters were monitored for six years, considering physical, chemical and microbiological parameters. Water quality was assessed using the NSF Water Quality Index (NSF-WQI) and the one calibrated for Lake Titicaca (WQIT). Comparing the efficiency of these two indices, the WQIT showed a variation from moderately polluted bays to bad quality bays, such as Desaguadero and Yunguyo. These two bays were classified as hypereutrophic, therefore, the uses attributable to this condition are only irrigation and energy production. Applying the NSF-WQI, the results were not able to identify this significative difference, as all bays were classified as moderate quality waters. This result indicates that the WQIT calibration was adequate, as it allows inferring and estimating the water quality of Lake Titicaca with greater precision. According to Peru’s water quality standard for category 4, established for the conservation of the country’s lakes, the parameters that exceeded the standard values were PO4-P (0.035 mg∙L−1) and BOD5 (5 mg∙L−1) in all bays, and TC (1000 MPN mL−1) in Yunguyo bay. These high values indicate eutrophication processes, one of the main problems in the study area. The WQIT calibrated for Lake Titicaca can be used as an efficient tool to assess water quality in high Andean lentic waterbodies in South America. 展开更多
关键词 Andean Lakes Water Quality Assessment eutrophication Water Quality index (WQIT)
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维生素E对小龙虾生长性能、组织生理指标及肌肉营养成分的影响
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作者 石丰运 陈明建 +1 位作者 随韶璞 曹忠新 《中国饲料》 北大核心 2024年第20期71-74,共4页
文章旨在研究维生素E(VE)对小龙虾生长性能、组织生理指标及肌肉营养成分的影响,试验选用平均体质量为(3.12±0.58)g的幼虾为研究对象,设置6个处理,每个处理3个重复,每个重复50尾小龙虾,各处理中VE的添加量分别为0,15,30,60,120和24... 文章旨在研究维生素E(VE)对小龙虾生长性能、组织生理指标及肌肉营养成分的影响,试验选用平均体质量为(3.12±0.58)g的幼虾为研究对象,设置6个处理,每个处理3个重复,每个重复50尾小龙虾,各处理中VE的添加量分别为0,15,30,60,120和240 mg/kg,进行为期60 d的饲养试验。结果表明:饲料中添加120 mg/kg及以上的VE显著提高了小龙虾的增重率,特定生长率和含肉率(P<0.05),显著降低了小龙虾的饲料系数(P<0.05),VE添加量对小龙虾的成活率和肝胰腺指数影响不显著(P>0.05)。饲料中添加120 mg/kg及以上的VE显著提高了小龙虾肠道蛋白酶和脂肪酶的活力,同时显著提高了肝胰腺中过氧化氢酶和超氧化物歧化酶的活力,显著提高了总抗氧化能力,并显著降低了肝胰腺中丙二醛的含量(P<0.05)。饲料中添加120 mg/kg及以上的VE显著提高了小龙虾肌肉中粗蛋白质含量,显著降低了粗脂肪含量(P<0.05)。研究表明,饲料中VE的添加水平可影响小龙虾的生长性能、生理指标及肌肉营养品质,且在本试验条件下最适添加量为120 mg/kg。 展开更多
关键词 克氏原螯虾 维生素e 生长性能 组织生理指标 肌肉营养成分
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饲粮中添加不同水平维生素E对贵州黑山羊生长性能、免疫指标以及肉品质的影响
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作者 杨洋 王清峰 +2 位作者 袁超 粟朝芝 肖文 《饲料工业》 CAS 北大核心 2024年第11期48-54,共7页
试验旨在探究饲粮中添加不同水平维生素E对贵州黑山羊生长性能、免疫性能和肉品质的影响。选取生长状况良好、平均体重为(21.66±1.64)kg的贵州黑山羊44只,采用完全随机设计分为4组,分别为对照组、试验1组、试验2组和试验3组,每组11... 试验旨在探究饲粮中添加不同水平维生素E对贵州黑山羊生长性能、免疫性能和肉品质的影响。选取生长状况良好、平均体重为(21.66±1.64)kg的贵州黑山羊44只,采用完全随机设计分为4组,分别为对照组、试验1组、试验2组和试验3组,每组11只,对照组和试验1、2、3组维生素E添加量分别为0、50、250、500 mg/(d·只),预试期7 d,正试期120 d,每天测定各组黑山羊的采食量,每隔30 d测定各组黑山羊的体重。试验结束后计算各组黑山羊的平均日采食量(ADFI)和平均日增重(ADG);采集各组黑山羊血液,测定血清免疫指标;每组随机选取3只黑山羊进行屠宰,测定肉质性状以及肌肉中氨基酸和脂肪酸的含量。结果表明:与对照组相比,试验2组的ADG提高了16.23%,免疫因子含量也有提高,其中IgA和IgG显著高于对照组(P<0.05);试验2组肌肉剪切力和滴水损失显著低于对照组(P<0.05),粗蛋白、多不饱和脂肪酸、油酸和亚油酸含量显著高于对照组(P<0.05)。综上所述,饲粮中维生素E添加量为250 mg/(d·只)时提升贵州黑山羊生长性能、免疫性能以及改善肉质指标的效果较好。 展开更多
关键词 维生素e 贵州黑山羊 生长性能 免疫指标 氨基酸 脂肪酸
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超声测定PI、RI、Vmax结合血清sE-cadherin、CYFRA21-1对乳腺癌良恶性及淋巴结转移的诊断价值
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作者 李海芬 邓亚云 +2 位作者 李洪来 戴林 汪凤勃 《生物医学工程与临床》 CAS 2024年第1期56-62,共7页
目的研究超声测定的搏动指数(PI)、血流阻力指数(RI)、最大血流值(Vmax)结合血清可溶性E-钙黏连蛋白(sE-cadherin)、细胞角蛋白19片段(CYFRA21-1)对乳腺癌良恶性及腋窝淋巴结转移的诊断价值。方法选择242例乳腺肿块女性患者,年龄43~67岁... 目的研究超声测定的搏动指数(PI)、血流阻力指数(RI)、最大血流值(Vmax)结合血清可溶性E-钙黏连蛋白(sE-cadherin)、细胞角蛋白19片段(CYFRA21-1)对乳腺癌良恶性及腋窝淋巴结转移的诊断价值。方法选择242例乳腺肿块女性患者,年龄43~67岁,平均年龄55.23岁;身体质量指数19.5~28.9 kg/m^(2),平均身体质量指数24.12 kg/m^(2);病程4~8个月,平均病程6.45个月;均为初次入院就诊。彩色多普勒超声仪测定PI、RI和Vmax,并在术前采集空腹外周血,酶联免疫吸附分析测定血清sE-cadherin和CYFRA21-1。根据病理组织诊断结果将患者分成乳腺癌组(n=132)和乳腺良性组(n=110),并将乳腺癌患者分成腋窝淋巴结转移组(n=74)和腋窝淋巴结未转移组(n=58)。单因素分析临床资料,Logistic回归分析乳腺癌发生和腋窝淋巴结转移的独立影响因素,通过受试者工作特性(ROC)曲线分析各指标及回归分析诊断效能。结果乳腺良恶性病变区分ROC曲线结果表明,PI临界值1.34,灵敏度为69.70%,特异度为70.91%,曲线下面积(AUC)为0.801[95%可信区间(CI)0.750~0.852];RI诊断的临界值为0.69,灵敏度为65.15%,特异度65.45%,AUC为0.762(95%CI 0.707~0.812);Vmax诊断的临界值为13.11 m/s,灵敏度为59.85%,特异度60.00%,AUC为0.627(95%CI 0.564~0.699);血清sE-cadherin诊断的临界值为24.18 ng/mL,灵敏度为62.88%,特异度58.18%,AUC为0.709(95%CI 0.645~0.771);血清CYFRA21-1诊断的临界值为9.55 g/mL,灵敏度为74.24%,特异度75.45%,AUC为0.817(95%CI 0.769~0.865)。将回归预测方程作为新变量P,在最佳临界切点时,回归分析灵敏度81.82%,特异度79.09%,AUC为0.867(95%CI 0.829~0.908),回归分析灵敏度显著高于各指标单独检测(P<0.05)。乳腺癌淋巴结转移分析ROC曲线结果表明,PI临界值1.58,灵敏度为79.73%,特异度为68.97%,AUC为0.815(95%CI 0.727~0.902);RI诊断的临界值为0.83,灵敏度为63.51%,特异度70.69%,AUC为0.701(95%CI 0.558~0.844);Vmax诊断的临界值为17.36 m/s,灵敏度为54.05%,特异度55.17%,AUC为0.516(95%CI 0.384~0.649);血清sE-cadherin诊断的临界值为34.52 ng/mL,灵敏度为82.43%,特异度60.34%,AUC为0.755(95%CI 0.653~0.856);血清CYFRA21-1诊断的临界值为13.10 g/mL,灵敏度为60.81%,特异度65.52%,AUC为0.563(95%CI 0.426~0.701)。将回归预测方程作为新变量P,在最佳临界切点时,回归分析灵敏度85.14%,特异度84.48%,AUC为0.893(95%CI 0.816~0.970),回归分析灵敏度显著高于各指标单独检测(P<0.05)。结论超声参数及血清sE-cadherin和CYFRA21-1在乳腺癌和腋窝淋巴结中异常表达,且PI、RI、Vmax和血清sE-cadherin、CYFRA21-1单独和Logistic回归分析可应用于乳腺恶性病变和淋巴结转移的预测和诊断。 展开更多
关键词 搏动指数 血流阻力指数 最大血流值 可溶性e-钙黏连蛋白 细胞角蛋白19片段 乳腺癌 淋巴结转移
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血清E-cadherin、IGFBP5在妊娠期糖尿病患者中的水平及其与胰岛素抵抗的关系
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作者 李亚华 何文慧 田利川 《检验医学与临床》 CAS 2024年第22期3326-3330,共5页
目的探讨妊娠期糖尿病患者血清E-钙黏蛋白(E-cadherin)和胰岛素样生长因子结合蛋白5(IGFBP5)水平及其与胰岛素抵抗的关系。方法选取2019年5月至2021年5月该院收治的84例妊娠期糖尿病患者作为观察组,根据胰岛素抵抗指数(HOMA-IR)将观察... 目的探讨妊娠期糖尿病患者血清E-钙黏蛋白(E-cadherin)和胰岛素样生长因子结合蛋白5(IGFBP5)水平及其与胰岛素抵抗的关系。方法选取2019年5月至2021年5月该院收治的84例妊娠期糖尿病患者作为观察组,根据胰岛素抵抗指数(HOMA-IR)将观察组分为胰岛素抵抗组(HOMA-IR>2.69)和无胰岛素抵抗组(HOMA-IR≤2.69)。另选取同期在该院进行健康体检的84例健康孕妇作为对照组。采用酶联免疫吸附试验检测所有研究对象血清E-cadherin、IGFBP5水平;采用Pearson相关分析胰岛素抵抗组血清E-cadherin、IGFBP5水平与HOMA-IR的相关性;采用受试者工作特征(ROC)曲线分析血清E-cadherin、IGFBP5对妊娠期糖尿病患者发生胰岛素抵抗的诊断价值。结果观察组血清E-cadherin水平低于对照组,血清IGFBP5水平高于对照组,差异均有统计学意义(P<0.05)。无胰岛素抵抗组年龄、孕产次、孕周、产前体质量指数、收缩压、舒张压、总胆固醇、甘油三酯与胰岛素抵抗组比较,差异均无统计学意义(P>0.05);无胰岛素抵抗组HOMA-IR低于胰岛素抵抗组,差异有统计学意义(P<0.05);胰岛素抵抗组血清E-cadherin水平低于无胰岛素抵抗组,血清IGFBP5水平高于无胰岛素抵抗组,差异均有统计学意义(P<0.05)。Pearson相关分析结果显示,胰岛素抵抗组血清E-cadherin水平与HOMA-IR呈负相关(P<0.05),血清IGFBP5水平与HOMA-IR呈正相关(P<0.05)。ROC曲线分析结果显示,血清E-cadherin、IGFBP5诊断妊娠期糖尿病患者发生胰岛素抵抗的曲线下面积(AUC)分别为0.746、0.811,最佳截断值分别为2325.58、27.67 ng/mL,2项联合检测诊断妊娠期糖尿病患者发生胰岛素抵抗的AUC为0.893。结论妊娠期糖尿病患者血清E-cadherin水平降低,IGFBP5水平升高,2项联合检测对妊娠期糖尿病患者发生胰岛素抵抗具有一定临床诊断价值。 展开更多
关键词 妊娠期糖尿病 e-钙黏蛋白 胰岛素样生长因子结合蛋白5 胰岛素抵抗 胰岛素抵抗指数
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Fuzzy Complex Index in Water Quality Assessment of Municipalities 被引量:3
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作者 Lei Zhu Han Hu 《Journal of Water Resource and Protection》 2010年第9期809-813,共5页
Donghu Lake in Wuhan is a multipurpose complex water body. However, its eutrophication phenomenon becomes increasingly serious. By making use of detailed and accurate contamination monitoring data and several mathemat... Donghu Lake in Wuhan is a multipurpose complex water body. However, its eutrophication phenomenon becomes increasingly serious. By making use of detailed and accurate contamination monitoring data and several mathematics models, we probe into the dynamic state of water quality. The year’s average value of major contamination index in Donghu Lake from 2001 to 2008 and fuzzy complex index are used to assess its short-term state of water quality. The results show that its water quality is basically stable in the 4th class of water quality standard GB3838-2002. 展开更多
关键词 FUZZY Complex index eutrophication SUBORDINATe DeGRee Water Quality Assessment
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Effect of Six-fourth Generation Cnaphalocrocis medinalis (Guenée) on Rice yield and Control Index 被引量:1
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作者 刘学儒 吴永方 +4 位作者 杨进 秦玉金 丁涛 赵阳 奚本贵 《Plant Diseases and Pests》 CAS 2010年第2期19-20,37,共3页
[Objective] The study aimed to find out effects of six-fourth generation Cnaphalocrocis medinalis (Guenée) on rice production in Yangzhou district and its control index. [Method] Through artificial control of i... [Objective] The study aimed to find out effects of six-fourth generation Cnaphalocrocis medinalis (Guenée) on rice production in Yangzhou district and its control index. [Method] Through artificial control of insects in field, four different insect volume gradients were set, the effects of different C. medinalis amounts on leaf roll rate and yield loss of Wuyunjing No.23 were determined. [Result] The results showed that within the range of 0-20 head/hill, as the amounts of insect increased, rice yield decreased, leaf roll rate and rice yield loss rate increased. According to 3% economic permit loss rate, the control index of C. medinalis on Wuyunjing No.23 was 173 head/hill. [Conclusion] The study would provide theoretical basis for effective controlling of six-fourth generation C. medinalis in Yangzhou district. 展开更多
关键词 Cnaphalocrocis medinalis(Guee) Leaf roll rate Yield loss Control index
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急性温度胁迫对红耳龟消化、免疫功能的影响及维生素E的干预效应 被引量:1
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作者 朱天生 李亦婷 +1 位作者 傅丽容 史海涛 《四川动物》 北大核心 2023年第5期498-507,共10页
为探究急性温度胁迫对红耳龟Trachemys scripta elegans消化和免疫功能的影响及饲料添加维生素E(VE)的干预效应。选取健康2龄红耳龟112只,分成未添加VE组和添加VE组(250 mg·kg^(−1)),每组设室温(30℃)、低温(17℃)和高温(35℃),于... 为探究急性温度胁迫对红耳龟Trachemys scripta elegans消化和免疫功能的影响及饲料添加维生素E(VE)的干预效应。选取健康2龄红耳龟112只,分成未添加VE组和添加VE组(250 mg·kg^(−1)),每组设室温(30℃)、低温(17℃)和高温(35℃),于胁迫0 h、6 h、12 h取血液和肠道组织,检测血清抗氧化酶和肠道消化酶活性。结果表明,未添加VE组低温下淀粉酶和脂肪酶的活性显著上升,谷胱甘肽(GSH)含量显著降低,高温下胃蛋白酶活性极显著升高,超氧化物歧化酶(SOD)活性显著升高,GSH含量显著下降;添加VE组急性温度胁迫下的SOD活性升幅减小,GSH含量升高,低温下胃蛋白酶活性显著提高,脂肪酶活性显著降低;高温下胃蛋白酶活性极显著降低,淀粉酶活性显著升高。本研究初步阐释了急性温度胁迫对红耳龟的损伤机制,同时发现饲料添加VE具有一定程度的缓解作用,为生产中应对急性温度应激探索了一条绿色可行途径。 展开更多
关键词 急性温度胁迫 维生素e 消化酶 抗氧化指标 红耳龟
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Surface thermal centroid anomaly of the eastern equatorial Pacific as a unified Nio index
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作者 方明强 陈艳 +1 位作者 李洪平 吴立新 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期1129-1136,共8页
By analyzing the variability of global SST (sea surface temperature) anomalies, we propose a unified Nifio index using the surface thermal centroid anomaly of the region along the Pacific equator embraced by the 0.7... By analyzing the variability of global SST (sea surface temperature) anomalies, we propose a unified Nifio index using the surface thermal centroid anomaly of the region along the Pacific equator embraced by the 0.7~C contour line of the standard deviation of the SST anomalies and try to unify the traditional Nifio regions into a single entity. The unified Nifio region covers almost all of the traditional Nifio regions. The anomaly time series of the averaged SST over this region are closely correlated to historical Nifio indices. The anomaly time series of the zonal and meridional thermal centroid have close correlation with historical TNI (Trans-Nifio index) indices, showing differences among E1 Nifio (La Nifia) events. The meridional centroid anomaly suggests that areas of maximum temperature anomaly are moving meridionally (although slightly) with synchronous zonal movement. The zonal centroid anomalies of the unified Nifio region are found helpful in the classification of the Eastern Pacific (EP)/Central Pacific (CP) types of E1 Nifio events. More importantly, the zonal centroid anomaly shows that warm areas might move during a single warming/cooling phase. All the current Nifio indices can be well represented by a simple linear combination of unified Nifio indices, which suggests that the thermal anomaly (SSTA) and thermal centroid location anomaly of the unified Nifio region would yield a more complete image of each E1 Nifio/ La Nina event. 展开更多
关键词 e1 Nino La Nifia unified Nifio index thermal centroid
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Analyzing the influences of two types of El Nino on Tropical Cyclone Genesis with a modified genesis potential index
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作者 王法明 杨宇星 杨磊 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第2期452-465,共14页
To understand the impacts of large-scale circulation during the evolution of E1 Nifio cycle on tropical cyclones (TC) is important and useful for TC forecast. Based on best-track data from the Joint Typhoon Warning ... To understand the impacts of large-scale circulation during the evolution of E1 Nifio cycle on tropical cyclones (TC) is important and useful for TC forecast. Based on best-track data from the Joint Typhoon Warning Center and reanalysis data from National Centers for Environmental Prediction for the period 1975- 2014, we investigated the influences of two types of E1 Nifio, the eastern Pacific E1 Nifio (EP-E1 Nifio) and central Pacific E1 Nifio (CP-E1 Nifio), on global TC genesis. We also examined how various environmental factors contribute to these influences using a modified genesis potential index (MGPI). The composites reproduced for two types of E1 Nifio, from their developing to decaying phases, were able to qualitatively replicate observed cyclogenesis in several basins except for the Arabian Sea. Certain factors of MGPI with more influence than others in various regions are identified. Over the western North Pacific, five variables were all important in the two E1Nifio types during developing summer (July-August-September) and fall (October- November-December), and decaying spring (April-May-June) and summer. In the eastern Pacific, vertical shear and relative vorticity are the crucial factors for the two types of El Nifio during developing and decaying summers. In the Atlantic, vertical shear, potential intensity and relative humidity are important for the opposite variation of EP- and CP-EI Nifios during decaying summers. In the Southern Hemisphere, the five variables have varying contributions to TC genesis variation during peak season (January-February-March) for the two types of E1 Nifio. In the Bay of Bengal, relative vorticity, humidity and omega may be responsible for clearly reduced TC genesis during developing fall for the two types and slightly suppressed TC cyclogenesis during EP-E1 Nifio decaying spring. In the Arabian Sea, the EP-E1 Nifio generates a slightly positive anomaly of TC genesis during developing falls and decaying springs, but the MGPI failed to capture this variation. 展开更多
关键词 two types of e1 Nifio tropical cyclone (TC) modified genesis potential index
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A subsurface intensity index of the cold eddy in the East China Sea
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作者 兰健 王毅 王刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1275-1280,共6页
The Cold Eddy in the East China Sea(CEECS) is located about 150 km southwest of Cheju Island.This region experiences a complex current system under the influences of the Yellow Sea Warm Current(YSWC),the Yellow Sea Co... The Cold Eddy in the East China Sea(CEECS) is located about 150 km southwest of Cheju Island.This region experiences a complex current system under the influences of the Yellow Sea Warm Current(YSWC),the Yellow Sea Coastal Current(YSCC),and the northward Kuroshio residual.To identify the strength of the CEECS,a simple subsurface intensity index is developed.Because the CEECS can be traced by temperature minimum,the intensity index is determined by the difference in sea temperature averaged across cores within and surrounding the region.Based on SODA,the CEECS subsurface intensity index time series can be calculated,with which the inter-annual variation of the CEECS is analyzed. 展开更多
关键词 cold eddy in the east China Sea (CeeCS) CeeCS subsurface intensity index inter-annualvariation e1 Nifio
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Experimental research on modulation degree of refractive index in the SCLP/E_7/C_(60) polymer using a fiber Fabry-Perot Interferometer
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作者 韩仁学 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第2期200-202,共3页
Modulation degree of refractive index is an important parameter for information storage in photorefractive materials. Using the relationship between the refractive index and the wavelengths of laser and the order of i... Modulation degree of refractive index is an important parameter for information storage in photorefractive materials. Using the relationship between the refractive index and the wavelengths of laser and the order of interference, we introduce a new method to measure the modulation degree of refractive index in photorefractive materials through detecting the shift of the interference fringe in a fiber Fabry-Perot interferometer with a CCD. The measurement precision is also analyzed. With this method, the modulation degree of refractive index in our prepared SCLP/E7/C 60 photorefractive polymer is measured for different external voltages and the external voltage corresponding to the maximal modulation degree of refractive index is reported. The dynamic change of refractive index in the SCLP/E7/C 60 is also studied, which will be helpful to understand the reaction mechanism of photochemistry in the material. 展开更多
关键词 modulation degree of refractive index Fabrv-Perot interferometer CCD SCLP/e7/C60
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Measurement of refractive index modulation on PMMA/E49/TNF/ECZ polymer-dispersed liquid crystal by fiber F-P interferometer
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作者 韩仁学 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第4期489-491,共3页
The fiber Fabry-Perot interferometer used to measure the refractive index modulation of polymer-dispersed liquid crystal is introduced.From measuring the quantity of the interference fringe shift with a CCD based on t... The fiber Fabry-Perot interferometer used to measure the refractive index modulation of polymer-dispersed liquid crystal is introduced.From measuring the quantity of the interference fringe shift with a CCD based on the theory of isoclinal interference fringes formatting,the maximal refractive index modulation versus different external voltages,3.899×10-3 in the external voltage of 57.4 V/μm,and the dynamic refractive index modulation versus response time in the external voltage of 8 V/μm are found in our prepared 1.250 mm-thick PMMA/E49/TNF/ECZ polymer-dispersed liquid crystals.The experimental results will be helpful to understand the photoinduced reaction mechanism of the material and optimize the mixture ratio of each component. 展开更多
关键词 refractive index modulation F-P interferometer PMMA/e49/TNF/eCZ
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维生素E对乳腺炎奶牛生产性能、血清生化及抗氧化指标的影响 被引量:3
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作者 尚迎辉 解军亮 张敏 《中国饲料》 北大核心 2023年第10期66-69,共4页
文章旨在研究维生素E对乳腺炎奶牛生产性能、血清生化及抗氧化指标的影响。试验选取20头胎次、产奶量相近,且患有隐性乳腺炎(体细胞数50万~100万个/m L)的荷斯坦奶牛,随机分为2组,每组10头奶牛。其中,对照组饲喂基础日粮,试验组饲喂基... 文章旨在研究维生素E对乳腺炎奶牛生产性能、血清生化及抗氧化指标的影响。试验选取20头胎次、产奶量相近,且患有隐性乳腺炎(体细胞数50万~100万个/m L)的荷斯坦奶牛,随机分为2组,每组10头奶牛。其中,对照组饲喂基础日粮,试验组饲喂基础日粮+1000IU的维生素E,试验为期30 d。结果显示:(1)与对照组相比,试验组奶牛平均日产奶量显著提高46.91%(P<0.05),乳汁中体细胞数显著降低23.56%(P<0.05)。(2)与对照组相比,试验组奶牛血清中总蛋白显著提高10.71%高(P<0.05),球蛋白显著提高17.18%(P<0.05),葡萄糖显著提高72.02%(P<0.05)。(3)与对照组相比,试验组奶牛血清总抗氧化能力显著提高30.08%(P<0.05),血清超氧化物歧化酶显著提高21.50%(P<0.05),丙二醛含量显著降低20.58%(P<0.05)。结论 :基础日粮+1000IU的维生素E可以提高奶牛产奶量,降低乳汁体细胞数,改善奶牛血清生化指标及抗氧化指标。 展开更多
关键词 维生素e 乳腺炎 奶牛 生产性能 血清生化 抗氧化指标
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甘肃地区阿尔茨海默病患者与载脂蛋白E基因型相关性
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作者 虎鹏娟 谷成 +3 位作者 姚宇平 高福林 张乐 张毅 《兰州大学学报(医学版)》 2023年第7期64-70,共7页
目的分析甘肃地区阿尔茨海默病患者和健康人群载脂蛋白E基因型分布,探讨阿尔茨海默病与载脂蛋白E的相关性。方法选取2018年10月-2022年6月在甘肃省人民医院神经内科确诊为阿尔茨海默病的患者63例作为阿尔茨海默病组,另收集同期体检中心... 目的分析甘肃地区阿尔茨海默病患者和健康人群载脂蛋白E基因型分布,探讨阿尔茨海默病与载脂蛋白E的相关性。方法选取2018年10月-2022年6月在甘肃省人民医院神经内科确诊为阿尔茨海默病的患者63例作为阿尔茨海默病组,另收集同期体检中心健康人群96例作为对照组,通过聚合酶链式反应—限制性片段长度多态性技术对载脂蛋白E基因型进行检测,分析比较两组基因型和等位基因分布情况,并测定血浆中的生化指标和脑脊液生物标志物水平。采用SPSS 25.0软件进行数据分析。结果(1)阿尔茨海默病组和对照组载脂蛋白E基因型频率差异有统计学意义(P=0.04),阿尔茨海默病组和对照组等位基因总体构成比较,差异有统计学意义(χ^(2)=11.65,P=0.003)。对ε2、ε3、ε4等位基因频率分别进行组间比较,阿尔茨海默病组ε4等位基因频率高于对照组,差异有统计学意义(P<0.05),两组ε2、ε3差异无统计学意义(P>0.05)。(2)两组总胆固醇、空腹血糖、尿酸水平比较,差异有统计学意义(P<0.05);甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇及同型半胱氨酸水平在两组间差异无统计学意义(P>0.05)。(3)两组脑脊液生物标志物β淀粉样蛋白42、β淀粉样蛋白42/β淀粉样蛋白40比值、磷酸化τ蛋白及人神经轻链蛋白水平比较,差异有统计学意义(P<0.05),两组β淀粉样蛋白40与总τ蛋白水平比较,差异无统计学意义(P>0.05)。(4)Logistic回归分析表明体重指数是阿尔茨海默病的保护性因素(OR=0.854,95%CI:[0.759,0.961],P=0.009),收缩压(OR=1.029,95%CI:[1.007,1.053],P=0.011)及载脂蛋白Eε4(OR=3.147,95%CI:[1.484,6.674],P=0.003)是阿尔茨海默病的危险因素。结论ε4是阿尔茨海默病的危险因素,甘肃地区阿尔茨海默病患者与载脂蛋白E基因相关。 展开更多
关键词 阿尔茨海默病 载脂蛋白e基因 生化指标 生物标志物 危险因素
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大疱性类天疱疮总IgE和CCL17表达水平与中医证型及疾病严重程度的相关研究
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作者 于研 李梦琳 +3 位作者 郭涛 王甜雪 苏畅 张峻岭 《中国中西医结合皮肤性病学杂志》 CAS 2023年第6期511-514,共4页
目的观察大疱性类天疱疮(BP)患者与健康人群血清总免疫球蛋白E(IgE)、皮肤组织中胸腺活化调节趋化因子(CCL17)表达水平的变化,分析2种指标在不同中医证型中的表达水平的差异以及与疾病严重程度的相关性。方法收集2019年1月—2021年1月... 目的观察大疱性类天疱疮(BP)患者与健康人群血清总免疫球蛋白E(IgE)、皮肤组织中胸腺活化调节趋化因子(CCL17)表达水平的变化,分析2种指标在不同中医证型中的表达水平的差异以及与疾病严重程度的相关性。方法收集2019年1月—2021年1月期间于天津市中医药研究院附属医院皮肤科住院,且确诊为BP的65例患者为病例组和皮肤外科有医疗美容需求的健康人群24例为对照组,采用酶联免疫吸附测定(ELISA)法检测血清总IgE及免疫组化染色测定皮损中趋化因子CCL17的表达水平,以大疱性类天疱疮面积指数评分(BPDAI)判定BP的严重程度,分析二者在不同中医证型中差异及与BPDAI相关性。结果病例组较对照组血清总IgE均明显升高,有显著统计学意义(kU/L:1101.70±848.40比62.47±28.81,P<0.001),血清总IgE在不同中医证型间差异均无统计学意义(P=0.115);病例组CCL17表达水平明显高于对照组(A值:0.36±0.08比0.17±0.07),差异有统计学意义(t=10.16,P<0.001),CCL17表达水平在不同中医证型间差异均无统计学意义(P=0.92)。血清总IgE与BPDAI总评分呈正相关(r=0.491,P<0.001),CCL17表达水平与BPDAI总评分之间呈正相关(r=0.256,P=0.040)。结论血清总IgE与趋化因子CCL17表达水平在BP患者中明显增高,二者均与疾病严重程度相关,有助于诊断BP生物标志物的开发,是BP患者靶向治疗的新靶点,可为临床医生诊断和治疗BP提供新的依据。 展开更多
关键词 大疱性类天疱疮 免疫球蛋白e 胸腺活化调节趋化因子 大疱性类天疱疮面积指数评分 疾病严重程度
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Spatial changes and driving factors of lake water quality in Inner Mongolia, China
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作者 REN Xiaohui YU Ruihong +10 位作者 LIU Xinyu SUN Heyang GENG Yue QI Zhen ZHANG Zhuangzhuang LI Xiangwei WANG Jun ZHU Penghang GUO Zhiwei WANG Lixin XU Jifei 《Journal of Arid Land》 SCIE CSCD 2023年第2期164-179,共16页
Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China,but the spatial patterns and driving mechanisms of water quality in lakes so far remain uncl... Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China,but the spatial patterns and driving mechanisms of water quality in lakes so far remain unclear.This study aimed to identify the spatial changes in water quality and the driving factors of seven lakes(Juyanhai Lake,Ulansuhai Lake,Hongjiannao Lake,Daihai Lake,Chagannaoer Lake,Hulun Lake,and Wulannuoer Lake)across the longitudinal axis(from the west to the east)of Inner Mongolia.Large-scale research was conducted using the comprehensive trophic level index(TLI(Σ)),multivariate statistics,and spatial analysis methods.The results showed that most lakes in Inner Mongolia were weakly alkaline.Total dissolved solids and salinity of lake water showed obvious zonation characteristics.Nitrogen and phosphorus were identified as the main pollutants in lakes,with high average concentrations of total nitrogen and total phosphorus being of 4.05 and 0.21 mg/L,respectively.The values of TLI(Σ)ranged from 49.14 to 71.77,indicating varying degrees of lake eutrophication,and phosphorus was the main driver of lake eutrophication.The lakes of Inner Mongolia could be categorized into lakes to the west of Daihai Lake and lakes to the east of Daihai Lake in terms of salinity and TLI(Σ).The salinity levels of lakes to the west of Daihai Lake exceeded those of lakes to the east of Daihai Lake,whereas the opposite trend was observed for lake trophic level.The intensity and mode of anthropogenic activities were the driving factors of the spatial patterns of lake water quality.It is recommended to control the impact of anthropogenic activities on the water quality of lakes in Inner Mongolia to improve lake ecological environment.These findings provide a more thorough understanding of the driving mechanism of the spatial patterns of water quality in lakes of Inner Mongolia,which can be used to develop strategies for lake ecosystem protection and water resources management in this region. 展开更多
关键词 SALINITY lake eutrophication lake water quality comprehensive trophic level index anthropogenic activities Daihai Lake Inner Mongolia
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经皮微创脊柱内固定治疗对创伤性胸腰椎骨折患者外周血TNF-α、MCP及PGE2水平的影响 被引量:6
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作者 高霖 谢勇辉 +1 位作者 陈诚 周坤 《临床误诊误治》 CAS 2023年第6期99-102,共4页
目的 探究经皮微创脊柱内固定治疗对创伤性胸腰椎骨折患者外周血肿瘤坏死因子-α(TNF-α)、单核细胞趋化蛋白(MCP)及前列腺素E2(PGE2)水平的影响。方法 选取2018年7月—2021年8月收治创伤性胸腰椎骨折152例为研究对象。根据治疗方案不... 目的 探究经皮微创脊柱内固定治疗对创伤性胸腰椎骨折患者外周血肿瘤坏死因子-α(TNF-α)、单核细胞趋化蛋白(MCP)及前列腺素E2(PGE2)水平的影响。方法 选取2018年7月—2021年8月收治创伤性胸腰椎骨折152例为研究对象。根据治疗方案不同分为对照组74例(给予Wiltse入路手术治疗)和观察组78例(给予经皮微创脊柱内固定治疗)。比较2组手术相关指标,手术前后TNF-α、MCP、PGE2水平和Oswestry功能障碍指数(ODI)评分变化,以及术后并发症发生情况。结果 观察组手术总时间长于对照组,术中出血量少于对照组,术后住院时间及骨折愈合时间短于对照组(P<0.01)。术后1、3、7 d, 2组TNF-α、MCP及PGE2水平均较术前明显升高,但观察组低于对照组(P<0.05)。术后1周、3个月、6个月,2组ODI评分均较术前明显降低,且观察组低于对照组(P<0.05)。观察组术后并发症总发生率为2.56%(2/78)低于对照组10.81%(8/74)(P<0.05)。结论 经皮微创脊柱内固定治疗可明显降低创伤性胸腰椎骨折患者外周血TNF-α、MCP及PGE2水平,促进患者恢复。 展开更多
关键词 脊柱骨折 创伤性胸腰椎骨折 经皮微创脊柱内固定 肿瘤坏死因子-α 单核细胞趋化蛋白 前列腺素e2 OSWeSTRY功能障碍指数 并发症
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Economic complexity and environmental sustainability in eastern European economies:Evidence from novel Fourier approach
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作者 Dervis KIRIKKALELI Emrah SOFUOGLU +1 位作者 Kashif Raza ABBASI Kwaku ADDAI 《Regional Sustainability》 2023年第4期349-358,共10页
Globally,economies have become complex and new technologies have transformed and facilitated the modernization of economies.In the previous literature,economic complexity approach has become one of the popular tools i... Globally,economies have become complex and new technologies have transformed and facilitated the modernization of economies.In the previous literature,economic complexity approach has become one of the popular tools in the development and innovation studies of economic geography.Researchers have found that green technology and eco-innovation approaches should be used to decisively reduce the effects of carbon emissions on the environment.However,debates about the impact of economic complexity on environment remain unsettled since some emerging production technologies have far-reaching pollution effects.This study explored the impacts of economic complexity on environmental sustainability in Turkey using the novel Fourier-based approaches,namely:Fourier Augmented Dickey-Fuller(FADF)and Fourier Autoregressive-Distributed Lag(FARDL)models.The Fourier-based approaches indicated that all variables(economic complexity index(ECI),GDP,energy consumption,and CO_(2)emission(CO_(2)E))are cointegrated in the long run.Additionally,the FARDL model implied that(i)in the long run,the effect of ECI(as a proxy for economic complexity),GDP(as a proxy for economic growth),and energy consumption on CO_(2)E(as a proxy for environmental quality)are important;(ii)economic complexity decreases environmental degradation in Turkey;and(iii)economic growth and energy consumption negatively affect environmental quality.The results also showed that economic complexity could be used as a policy tool to tackle environmental degradation.The findings also revealed that the fossil fuelbased economy will continue to expand and undermine Turkey’s efforts to meet its net zero emission target by 2053.Therefore,policy-makers should take actions and establish diversified economic,environmental,and energy strategies.For policy insights,the Turkish governments can use the combination of tax exemptions and technical support systems to support knowledge creation and the diffusion of environmentally friendly technologies The governments can also impose strict environmental regulations on the knowledge development phases. 展开更多
关键词 economic complexity environmental degradation CO_(2)emission(CO_(2)e) Fourier Autoregressive-Distributed Lag(FARDL) Fourier Augmented Dickey-Fuller(FADF) economic complexity index(eCI) Turkey
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