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Sex Pheromone Components of the Female Black Cutworm Moth in China: Identification and Field Trials 被引量:5
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作者 向玉勇 杨茂发 李子忠 《Zoological Research》 CAS CSCD 北大核心 2009年第1期59-64,共6页
The sex pheromone blend of a China strain of the black cutworm moth Agrotis ypsilon (Rottemberg) (Lepidoptera: Noctuidae) was investigated. Chemical analysis of pheromone gland extracts of 3-day-old females showe... The sex pheromone blend of a China strain of the black cutworm moth Agrotis ypsilon (Rottemberg) (Lepidoptera: Noctuidae) was investigated. Chemical analysis of pheromone gland extracts of 3-day-old females showed that individual isolated glands contained only very small amounts of pheromone. The high-resolution gas chromatography combined with mass spectrometry (GC-MS) analysis showed the presence of Cis-7-dodecenyl acetate (Z7-12:Ac, A), Cis-9-tetradecenyl acetate (Z9-14:Ac, B), Cis- 11-hexadecenyl acetate (Z 11 - 16 :Ac, C), Cis-8-dodecenyl acetate (Z8-12:Ac, E) and Cis-5-decenyl acetate (Z5-10:Ac, D) in biologically active pheromone gland extracts. An extract of one gland from a day 3 female gave the following values for the gland components: 0.245±0.098ng for Z7-12:Ac, 0.080±0.031ng for Z9-14:Ac, 0.089±0.033ng for Z11-16:Ac, 0.085±0.031ng for Z5-10:Ac, 0.105±0.065ng for Z8-12:Ac per female. The percentages of Z7-12:Ac, Z9-14:Ac, Z11-16:Ac, Z5-10:Ac and ZS-12:Ac in pheromone gland extracts from individual females were (meaniSE) 40.451±13.66, 13.176±5.279, 14.943±5.142, 14.392±6.10 and 17.225±9.792 respectively, and the percentages of Z7-12:Ac, Z9-14:Ac and Z11-16:Ac were 58.75±9.429, 18.91±7.539 and 22.34±7.209. Field trials indicated that each single component of sex pheromone was non-effective and captured no males. The lures baited with duality compound of AB (3 : 1) had a certain attraction to males, the mean captured number was 2.6. The attraction ability of the lures baited with ternary compound of ABC (3 : 1 :1) to males added significantly, the mean captured number per trap was 7.40, which was 2.8 times of duality compound of AB (3 : 1). The contents of sex pheromone could obviously affect its capture ability to males, the mean captured number was the highest at the dosage of 200 μg. 展开更多
关键词 Agrotis ypsilon Chemical analysis field trial Gas chromatography/High-resolution mass spectrometry Internal standard Sex pheromone Standard chemicals
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Effects of Long-Term Organic Amendments on Soil Organic Carbon in a Paddy Field: A Case Study on Red Soil 被引量:9
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作者 HUANG Qing-hai LI Da-ming +8 位作者 LIU Kai-lou YU Xi-chu YE Hui-cai HU Hui-wen XU Xiao-lin WANG Sai-lian ZHOU Li-jun DUAN Ying-hua ZHANG Wen-ju 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第3期570-576,共7页
Soil organic carbon (SOC) is one of the main carbon reservoirs in the terrestrial ecosystem. It is important to study SOC dynamics and effects of organic carbon amendments in paddy fields because of their vest expan... Soil organic carbon (SOC) is one of the main carbon reservoirs in the terrestrial ecosystem. It is important to study SOC dynamics and effects of organic carbon amendments in paddy fields because of their vest expansion in south China. A study was carried out to evaluate the relationship between the SOC content and organic carbon input under various organic amendments at a long-term fertilization experiment that was established on a red soil under a double rice cropping system in 1981. The treatments included non-fertilization (CK), nitrogen-phosphorus-potassium fertilization in early rice only (NPK), green manure (Astragalus sinicus L.) in early rice only (OM1), high rate of green manure in early rice only (OM2), combined green manure in early rice and farmyard manure in late rice (OM3), combined green manure in early rice, farmyard manure in late rice and rice straw mulching in winter (OM4), combined green manure in early rice and rice straw mulching in winter (OMS). Our data showed that the SOC content was the highest under OM3 and OM4, followed by OM1, OM2 and OM5, then NPK fertilization, and the lowest under non-fertilization. However, our analyses in SOC stock indicated a significant difference between OM3 (33.9 t ha^-1) and OM4 (31.8 t ha^-1), but no difference between NPK fertilization (27 t ha^-1) and nonfertilization (28.1 t ha^-1). There was a significant linear increase in SOC over time for all treatments, and the slop of linear equation was greater in organic manure treatments (0.276-0.344 g kg-1 yr^-1) than in chemical fertilizer (0.216 g kg^-1 yr^-1) and no fertilizer (0.127 g kg^-1 yr^-1). 展开更多
关键词 long-term field experiment organic amendments soil organic carbon paddy soil derived from red earth
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Effects of Long-term Fertilization on Soil M icrobial Com m unity Structure,Labile Organic Carbon and Nitrogen and Enzym e Activity in Paddy Field and Upland 被引量:4
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作者 Wang Guiyue Su Ting +3 位作者 Han Hailiang Tan Heping Bao Fei Zhao Fucheng 《Meteorological and Environmental Research》 CAS 2019年第5期105-111,共7页
To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was c... To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was conducted at the experimental station of Dongyang Institute of Maize Research in Zhejiang Province,China in 2009.The experiment consisted of six treatments with three replicates,and they were arranged in a completely randomized design,including no fertilization in paddy field (PCK),conventional fertilization in paddy field (PCF),formulated fertilization by soil testing in paddy field (PSTF),formulated fertilization by soil testing with organic manure in paddy field (PSTF+OF),conventional fertilization on upland (DCF),and formulated fertilization by soil testing with organic manure on upland (DSTF+OF).Soil nutrients,enzyme activity,microbial biomass and community structure were determined in 2015.The results showed that compared with no fertilization in paddy field (PCK),fertilization increased soil phosphorus and potassium content,and decreased pH value.No fertilization in paddy field (PCK) had no significant effect on soil culturable microorganisms in paddy field and upland,but formulated fertilization by soil testing with organic manure on upland (DSTF+OF) significantly increased the number of fungi.Formula fertilization by soil testing with organic manure (PSTF+OF) also significantly increased soil microbial biomass carbon and nitrogen in paddy field and upland.Moreover,fertilization had no significant effect on soil cellulase activity,but formula fertilization by soil testing with organic manure (PSTF+OF) significantly increased soil dehydrogenase and catalase activity.Therefore,long-term application of chemical fertilizer with organic fertilizer can effectively improve soil fertility. 展开更多
关键词 long-term fertilization Paddy field UPLAND Microbial community STRUCTURE SOIL enzyme ACTIVITY
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5G Features from Operation Perspective and Fundamental Performance Validation by Field Trial 被引量:2
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作者 Guangyi Liu Yuhong Huang +2 位作者 Fei Wang Jianjun Liu Qixing Wang 《China Communications》 SCIE CSCD 2018年第11期33-50,共18页
The fast deployment and penetration of 4G has cultivated human behaviors on mobile data consumption, leading to explosive growth in mobile traffic and stimulating new requirements on the capabilities of mobile network... The fast deployment and penetration of 4G has cultivated human behaviors on mobile data consumption, leading to explosive growth in mobile traffic and stimulating new requirements on the capabilities of mobile networks. To meet the requirements of mobile networks toward year 2020, the next genera- tion of mobile networks (termed as IMT-2020, or 5G) is designed to support 100 Mbps-1 Gbps user-experienced data rate, 1 ms radio transmission latency, and 1 million connec- tions per square kilometer. Recalling the vision and requirements of 5G targeting for commer- cial launch in 2020, this article overviews the key features of 5G and compares with those of 4G, and reports the world first field trials conducted to validate the key performance of 5G radio interface in 3.SGHz band. The trial results show that a 1 ms transmission latency and 1 Gbps data rate are achievable. 展开更多
关键词 5G IMT-2020 3D-MIMO usercentric network software defined network Network Function Virtualization field trial
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Field Trials of CpGV Virus Isolates Overcoming Resistance to CpGV-M
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作者 M. Berling J. -B. Rey +5 位作者 S. -J. Ondet Y. Tallot O. Soubabère A. Bonhomme B. Sauphanor M. Lopez-Ferber 《Virologica Sinica》 SCIE CAS CSCD 2009年第5期470-477,共8页
The Cydia pomonella granulovirus (CpGV) has been used for many years as biological agent for codling moth control in apple orchards. Resistance to the Mexican strain of CpGV was detected in orchards in Germany, France... The Cydia pomonella granulovirus (CpGV) has been used for many years as biological agent for codling moth control in apple orchards. Resistance to the Mexican strain of CpGV was detected in orchards in Germany, France and Italy. A laboratory insect colony was started from insects collected in a French resistant orchard. It was named RGV. Various virus isolates were identified as active against this resistant insect colony. Field tests were carried out in 2007 to test if the two virus isolates CpGV-I12 and NPP-R1 were effective in the field. Although these virus isolates were not able to reduce insect caused fruit damages, they significantly reduced the overwintering insect populations. NPP-R1 was subjected to eight passages on RGV larvae (NPP-R1.8) that improved its biological activity on RGV larvae. 2008 field trials were set up to test this improved virus strain, compared to CpGV-I12 and Madex plus active on RGV. These tests confirmed the ability to control both in susceptible and resistant insect populations. 展开更多
关键词 Cydia pomonella Codling moth Biological control Genotype selection field trials
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The Field Efficacy Trial of Several Fungicides for Controlling Rice Sheath Blight Disease (Rhizoctonia solani)
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作者 Huang Xianliang Jiang Xianya +4 位作者 Chen Maotuo Huang Riliang Wu Shangxin Lu Xixu Yang Jianyuan 《Plant Diseases and Pests》 CAS 2020年第3期18-20,30,共4页
[Objective]The paper was to study the field fficacy of several fumgicide against rice sheath bligh(Rhicoetonia solm).[Method]Field efficacy trial was performed with three novel fungicides,75%tebuconazole.azxytrobin WG... [Objective]The paper was to study the field fficacy of several fumgicide against rice sheath bligh(Rhicoetonia solm).[Method]Field efficacy trial was performed with three novel fungicides,75%tebuconazole.azxytrobin WG,75%tifloxystrobion-tebuconazole WG and 24%6 thi-fluzamide sC,while 30%difenoconazole-propiconazole EC and 10%jingangmyein AS,which had been Long circulated in production,were uwsed as contrl agents.[Result]The three novel fungicides had better control ffe on sheath blight than the control agents;75%tebuconazole.azoxys-trobin WG at the dase of 20 g/667 m2 received the best contrl efect,and the control efect was still 87.72%at 20 d post administration,and the yield increase efect was remarkable.The control efects of 75%tiloxystrobin-tebuconazole wG and 24%thifluzamide SC were 85.67%and 87.36%,repectively.[Conclusion]75%tebuconazole.azxoxystrobin wG,75%tifloxystrobin tebuconazole WC and 24%thiluamide SC could be promted as rotation fungicides to control rice sheath blight. 展开更多
关键词 RICE Sheath blight FUNGICIDE field trial
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Long-Term Animal Feeding Trial of the Refined Konjac Meal Ⅱ. Effects of the Refined Konjac Meal on the Aging of the Brain, Liver, and Cardiovascular Tissue Cells in Rats
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作者 PENG SHU-SHENG ZHANG MAO-YU +1 位作者 ZHANG YIN-ZU AND WU ZI-HUA(School of Public Health, West China University of Medical Sciences,Chengdu 610041, China) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1995年第1期80-87,共8页
Rats of both sexes were fed on a basal feed containing 1% refined konjac meal (RKM) for 18 months and the effects of RKM on the cell aging were observed. A comparable group fed on the basic feed was used as the contro... Rats of both sexes were fed on a basal feed containing 1% refined konjac meal (RKM) for 18 months and the effects of RKM on the cell aging were observed. A comparable group fed on the basic feed was used as the control. Results obtained demonstrate that the long-term feeding of RKM to rats can delay the course of cell aging of the gliocyte, cadiomyocyte, and the endothelial cell of the large and medium arteriases, hence it is likely to delay the occurrence of arteriosclerosis and improve the functions of the brain, heart and vascular system. 展开更多
关键词 and Cardiovascular Tissue Cells in Rats Liver Effects of the Refined Konjac Meal on the Aging of the Brain long-term Animal Feeding trial of the Refined Konjac Meal
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Long-Term Animal Feeding Trial of the Refined Konjac Meal Ⅰ. Effects of the Refined Konjac Meal on the Calcium and Phosphorus Metabolism and the Bone in Rat
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作者 ZHANG MAO-YU PENG SHU-SHENG +1 位作者 ZHANG YIN-ZHU AND WU ZI-HUA(School of Public Health, West China University of Medical Sciences,Chengdu 610041, China) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1995年第1期74-79,共6页
Effects of refined konjac meal (RKM) on the calcium and phosphorus metabolism and bone parameters were observed in rats of both sexes fed with food containing 1% of RKM for 18 months. A comparable group of rats fed on... Effects of refined konjac meal (RKM) on the calcium and phosphorus metabolism and bone parameters were observed in rats of both sexes fed with food containing 1% of RKM for 18 months. A comparable group of rats fed on basic diet only was used as a control.Results obtained indicate that all the measured parameters (serum calcium and phosphorus level, femur weight and its calcium and phesphorus content, and the osteometry of the tibia) showed no significant difference between the experimental and the control groups.Thus there is no adverse effect either on the calcium and phosphorus metabolism or on the bone after a long-term intake at a moderate dosage. 展开更多
关键词 Jun Effects of the Refined Konjac Meal on the Calcium and Phosphorus Metabolism and the Bone in Rat long-term Animal Feeding trial of the Refined Konjac Meal
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Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge
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作者 Xilong Zheng Qiong Wang Di Guan 《Structural Durability & Health Monitoring》 EI 2024年第3期361-376,共16页
The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation ... The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively. 展开更多
关键词 Continuous rigid frame bridge REHABILITATION long-term monitoring field load test safety standard determination
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基于视觉导航的设施喷雾机电动底盘设计与试验
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作者 史运铎 袁永伟 +1 位作者 刘江涛 弋景刚 《农机化研究》 北大核心 2025年第3期227-233,共7页
喷雾作业在设施农业作物生产中起着关键的作用,针对当前设施喷雾作业多以人工喷洒完成,机械化水平较低、底盘转向不灵活、农药利用率低,且人工喷洒易造成农药残留伤害人体健康等问题,设计了一款基于视觉导航实现自主行走的设施喷雾机底... 喷雾作业在设施农业作物生产中起着关键的作用,针对当前设施喷雾作业多以人工喷洒完成,机械化水平较低、底盘转向不灵活、农药利用率低,且人工喷洒易造成农药残留伤害人体健康等问题,设计了一款基于视觉导航实现自主行走的设施喷雾机底盘,完成了喷雾机底盘的机械结构设计,并对底盘的控制系统、驱动系统和软件流程进行设计。试验结果表明:设计的设施喷雾机底盘可以实现灵活转向和基于视觉导航自主行走,底盘3种标签试验平均成功率为98.67%;直线行驶10 m时,横向偏差平均值为2.1 cm,最大值为6.7 cm,底盘驱动系统和控制系统稳定。提高喷雾机作业的自动化和智能化,降低农民的生产作业强度,对设施农业现代化具有重要意义。 展开更多
关键词 视觉导航 喷雾机底盘 控制系统 田间试验
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低频脉冲磁场慢性暴露对健康成年股四头肌收缩力及形态的影响
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作者 王选强 张文洋 +5 位作者 李阳 孔维签 李伟 王乐 厉中山 白石 《中国组织工程研究》 CAS 北大核心 2025年第8期1634-1642,共9页
背景:目前已有关于低频脉冲磁场对骨骼肌结构形态影响研究发现了骨骼肌质量变化,但对接受慢性暴露后的形态变化未见相关研究。目的:观察低频脉冲磁场慢性暴露对腿部股四头肌最大自主收缩力与形态指标的影响,为使用该技术作为肌肉功能改... 背景:目前已有关于低频脉冲磁场对骨骼肌结构形态影响研究发现了骨骼肌质量变化,但对接受慢性暴露后的形态变化未见相关研究。目的:观察低频脉冲磁场慢性暴露对腿部股四头肌最大自主收缩力与形态指标的影响,为使用该技术作为肌肉功能改善策略提供组织形态变化的参考依据。方法:招募普通健康受试者70名,随机分为接受磁场刺激的试验组与进行假治疗的对照组,每组35名,试验时长共计4周,试验组受试者每隔48 h进行1次15 min的低频脉冲磁刺激干预,对照组进行假治疗,干预间隔与时长与试验组一致,干预4周后观察不同组别受试者股四头肌最大自主收缩力值变化,利用B型超声影像作为评估手段,观察肌肉厚度、肌肉横截面积及羽状角指标的变化。结果与结论:①经过4周的低频脉冲磁场慢性暴露,68名受试者完成试验,试验组受试者股四头肌最大自主收缩力测试值显著增长(P=0.000),提升幅度显著高于对照组(P=0.008);②试验组受试者的肌肉形态3项指标均显著高于试验前测(P=0.000),而对照组肌肉厚度指标呈显著性下降(P=0.020),羽状角无显著性变化,横截面积显著性提升(P=0.000);③组间对比发现,试验组关于肌肉形态的肌肉厚度(P=0.012)、羽状角(P=0.003)及横截面积(P=0.049)3项指标均显著高于对照组;④上述数据证实,健康成年受试者经过4周的低频脉冲磁场慢性暴露,股四头肌的最大自主收缩力显著提升,同时观察到试验组的肌肉厚度、横截面积及羽状角3项肌肉形态指标的显著增长,对使用该技术作为肌肉改善的运动替代与医疗策略提供了肌组织形态改善的支持依据。 展开更多
关键词 低频脉冲磁场 慢性暴露 瞬时感受器电位通道1 TRPC1 骨骼肌形态结构 最大自主收缩力 肌骨超声 肌肉厚度 肌肉横截面积 羽状角 双盲试验
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Long-term results of paclitaxel plus cisplatin with concurrent radiotherapy for loco-regional esophageal squamous cell carcinoma 被引量:15
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作者 Han-Ting Zhu Da-Shan Ai +10 位作者 Hua-Rong Tang Harun Badakhshi Jian-Hong Fan Jia-Ying Deng Jun-Hua Zhang Yun Chen Zhen Zhang Yi Xia Xiao-Mao Guo Guo-Liang Jiang Kuai-Le Zhao 《World Journal of Gastroenterology》 SCIE CAS 2017年第3期540-546,共7页
AIM To evaluate the long-term effectiveness and late toxicities of paclitaxel(PTX) plus cisplatin(DDP) with concurrent radiotherapy for locally advanced esophageal squamous cancer.METHODS Between 2008 and 2011, 76 pat... AIM To evaluate the long-term effectiveness and late toxicities of paclitaxel(PTX) plus cisplatin(DDP) with concurrent radiotherapy for locally advanced esophageal squamous cancer.METHODS Between 2008 and 2011, 76 patients were enrolled in a phase Ⅱ study on the treatment of loco-regionally advanced esophageal cancer with radiotherapy(68.4 Gy/44 fractions or 61.2 Gy/34 fractions) combined with 4-cycle chemotherapy consisting of DDP(25 mg/m^2 per day for 3 d) and PTX(175 mg/m^2 for 3 h). The primary endpoints were overall survival and progression-free survival, and the secondary endpoints were toxicity and the treatment failure pattern.RESULTS A total of 76 patients were enrolled in this study, of whom 63.2% finished the whole regimen. The 5-year survival rates for the per-protocol population and intent-to-treat population were 25.4% and 26.4%, respectively, and the median survival rates were 23.7 mo and 28.5 mo, respectively. Grade 3 or 4 late toxicity was observed in only one patient(heart failure). In log-rank analysis, the pretreatment stage(stage Ⅱ + Ⅲ: 36.1 mo vs stage Ⅳ: 14.9 mo) and the completed cycle(1-3 cycles: 16.1 mo vs 4 cycles: 35.5 mo) were significant prognostic factors(P = 0.037 < 0.05 and P = 0.013 < 0.05).CONCLUSION Radiotherapy combined with chemotherapy consisting of PTX and DDP is a safe and effective definitive treatment for loco-regionally advanced esophageal squamous cancer. 展开更多
关键词 CHEMORADIOTHERAPY long-term result Loco-regionally advanced esophageal cancer Phase trial
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Discrepancy in Response of Rice Yield and Soil Fertility to Long-Term Chemical Fertilization and Organic Amendments in Paddy Soils Cultivated from Infertile Upland in Subtropical China 被引量:12
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作者 LIU Ming LI Zhong-pei +2 位作者 ZHANG Tao-lin JIANG Chun-yu CHE Yu-ping 《Agricultural Sciences in China》 CAS CSCD 2011年第2期259-266,共8页
From 1990,over 17 years field experiment was carried out in paddy field cultivated from infertile upland to evaluate the response of rice productivity,soil organic carbon(SOC),and total N to long-term NPK fertilizat... From 1990,over 17 years field experiment was carried out in paddy field cultivated from infertile upland to evaluate the response of rice productivity,soil organic carbon(SOC),and total N to long-term NPK fertilization or NPK combined with organic amendments.The field trials included NPK(N,P,K fertilizer),NPKRS(NPK combined with rice straw),NPK2RS(NPK combined with double amount of rice straw),NPKPM(NPK combined with pig manure) and NPKGM(NPK combined with green manure) and the cropping system was rice-rice(Oryza sativa L.) rotation.Annual rice yield,straw biomass,and harvesting index increased steadily with cultivation time in all treatments.Average annual rice yield from 1991 to 2006 was ranged from 7 795 to 8 572 kg ha-1 among treatments.Rice yields in treatments with organic amendments were usually higher than that in treatment with NPK.Contents of SOC and total N also increased gradually in the cultivation years and reached the level of 7.82 to 9.45 and 0.85 to 1.03 g kg-1,respectively,in 2006.Soil fertilities in treatments with chemical fertilization combined with organic amendments were relatively appropriate than those in treatment with NPK.There was obvious discrepancy between cumulative characters of rice yield and soil organic fertility in newly formed paddy field.Compared with relatively high rate of crop productivity improvement,cumulative rates of SOC and total N were much lower in our study.SOC and total N contents were still less than half of those in local highly productive paddy soils after 17 years cultivation in subtropical China.Present work helps to better understand the development of infertile paddy soils and to estimate the potential of yield improvement in this region. 展开更多
关键词 paddy field rice yield SOC total N long-term field experiment
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Hippocampal ischemia causes deficits in local field potential and synaptic plasticity 被引量:8
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作者 Shaoli Wang Jingyun Zhang +2 位作者 Tao Sheng Wei Lu Dengshun Miao 《The Journal of Biomedical Research》 CAS CSCD 2015年第5期370-379,共10页
The long-term enhancement in glutamate receptor mediated excitatory responses has been observed in stroke model. This pathological form of plasticity, termed post-ischemic long-term potentiation (i-LTP), points to f... The long-term enhancement in glutamate receptor mediated excitatory responses has been observed in stroke model. This pathological form of plasticity, termed post-ischemic long-term potentiation (i-LTP), points to functional reorganization after stroke. Little is known, however, about whether and how this i-LTP would affect subsequent induction of synaptic plasticity. Here, we first directly confirmed that i-LTP was induced in the endothelin-l-induced ischemia model as in other in vitro models. We also demonstrated increased expression of NR2B, CaMKII and p-CaMKII, which are reminiscent of i-LTP. We further induced LTP of field excitatory post- synaptic potentials (fEPSPs) on CA1 hippocampal neurons in peri-infarct regions of the endothelin-l-induced mini-stroke model. We found that LTP of fEPSPs, induced by high-frequency stimulation, displayed a progressive impairment at 12 and 24 hours after ischemia. Moreover, using in vivo multi-channel recording, we found that the local field potential, which represents electrical property of cell ensembles in more restricted regions, was also dam- pened at these two time points. These results suggest that i-LTP elevates the induction threshold of subsequent synap- tic plasticity. Our data helps to deepen the knowledge of meta-synaptic regulation of plasticity after focal ischemia. 展开更多
关键词 long-term potentiation local field potential ISCHEMIA ENDOTHELIN-1 multi-channel in vivo recording
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Short-and long-term behaviors of drifts in the Callovo-Oxfordian claystone at the Meuse/Haute-Marne Underground Research Laboratory 被引量:5
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作者 G.Armand A.Noiret +1 位作者 J.Zghondi D.M.Seyedi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2013年第3期221-230,共10页
Since 2000, the French National Radioactive Waste Management Agency (ANDRA) has been constructing an Underground Research Laboratory (URL) at Bure (east of the Paris Basin) to perform experiments in order to obt... Since 2000, the French National Radioactive Waste Management Agency (ANDRA) has been constructing an Underground Research Laboratory (URL) at Bure (east of the Paris Basin) to perform experiments in order to obtain in situ data necessary to demonstrate the feasibility of geological repository in the Callovo- Oxfordian claystone. An important experimental program is planned to characterize the response of the rock to different drift construction methods, Before 2008, at the main level of the laboratory, most of the drifts were excavated using pneumatic hammer and supported with rock bolts, sliding steel arches and fiber shotcrete. Other techniques, such as road header techniques, stiff and flexible supports, have also been used to characterize their impacts. The drift network is developed following the in situ major stresses. The parallel drifts are separated enough so as they can be considered independently when their hydromechanical (HM) behaviors are compared. Mine-by experiments have been performed to measure the HM response of the rock and the mechanical loading applied to the support system due to the digging and after excavation. Drifts exhibit extensional (mode I) and shear fractures (modes II and III) induced by excavation works. The extent of the induced fracture networks depends on the drift orientation versus the in situ stress field. This paper describes the drift convergence and deformation in the surrounding rock walls as function of time and the impact of different support methods on the rock mass behavior. An observation based method is finally applied to distinguish the instantaneous and time-dependent parts of the rock mass deformation around the drifts. 展开更多
关键词 field experiments Claystone Tunnel convergence Induced fractures Short- and long-term behaviors
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Systematic review of long-term Xingnao Kaiqiao needling efficacy in ischemic stroke treatment 被引量:7
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作者 Zhi-xin Yang Jia-hong Xie +4 位作者 Yong-ping Liu Guang-xin Miao Ying-han Wang Sheng-mei Wu Yuan Li 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第4期583-588,共6页
OBJeCTIve:To systematically evaluate the long-term effect and safety ofXingnao Kaiqiao nee-dling method in ischemic stroke treatment. DATA ReTRIevAL: We retrieved relevant random and semi-random controlled trials th... OBJeCTIve:To systematically evaluate the long-term effect and safety ofXingnao Kaiqiao nee-dling method in ischemic stroke treatment. DATA ReTRIevAL: We retrieved relevant random and semi-random controlled trials that used theXingnao Kaiqiao needling method to treat ischemic stroke compared with various control treatments such as conventional drugs or other acupuncture therapies. Searched databases included China National Knowledge Infrastructure, Weipu Information Resources System, Wanfang Medical Data System, Chinese Biomedical Literature Database, Cochrane Library, and PubMed, from May 2006 to July 2014. SeLeCTION CRITeRIA: Two authors independently conducted literature screening, quality evaluation, and data extraction. The quality of articles was evaluated according to the Cochrane Reviewers’ Handbook 5.1, and the study was carried out using Cochrane system assessment methods. RevMan 5.2 was used for meta-analysis of the included studies. MAIN OUTCOMe MeASUReS: Mortality rate, recurrence rate, and disability rate were observed. ReSULTS:Nine randomized and semi-randomized controlled trials treating 931 cases of ischemic stroke were included in this review. Meta-analysis results showed that there were no sig-niifcant differences in mortality reduction (risk ratio (RR) = 0.58, 95% conifdence interval (CI): 0.17–1.93,Z = 0.89,P = 0.37) or recurrence rate (RR = 0.55, 95%CI: 0.18–1.70,Z = 1.04,P = 0.30) of ischemic stroke patients between theXingnao Kaiqiao needling and control treatment groups. However, theXingnao Kaiqiao needling method had a tendency towards higher efifcacy in mor-tality reduction and recurrence rates. TheXingnao Kaiqiao needling method was signiifcantly better than that of the control treatment in reducing disability rate (RR = 0.51, 95%CI: 0.27–0.98, Z = 2.03,P 〈 0.05). CONCLUSION:TheXingnao Kaiqiao needling method has a better effect than control treatment in reducing disability rate. The long-term effect ofXingnao Kaiqiao needling against ischemic stroke is better than that of control treatment. However, the limitations of this study limit the strength of the conclusions. Randomized controlled trials with a strict, reasonable design, and multi-center, large-scale samples and follow-up are necessary to draw conclusions aboutXingnao Kaiqiao needling. 展开更多
关键词 nerve regeneration Xingnao Kaiqiao needling method ischemic stroke randomized controlled trial systemic reviews meta-analysis long-term efficacy MORTALITY RECURRENCE DISABILITY adverse reactions health economics indicators neural regeneration
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Field Transmission of 100G and Beyond:Multiple Baud Rates and Mixed Line Rates Using Nyquist-WDM Technology 被引量:2
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作者 Zhensheng Jia Jianjun Yu +2 位作者 Hung-Chang Chien Ze Dong Di Huo 《ZTE Communications》 2012年第3期28-38,共11页
In this paper, we describe successful joint experiments with Deutsche Telecom on long-haul transmission of 100G and beyond over standard single mode fiber (SSMF) and with in-line EDFA-only amplification. The transmi... In this paper, we describe successful joint experiments with Deutsche Telecom on long-haul transmission of 100G and beyond over standard single mode fiber (SSMF) and with in-line EDFA-only amplification. The transmission link consists of 8 nodes and 950 km installed SSMF in DT' s optical infrastructure. Laboratory SSMF was added for extended optical reach. The first field experiment involved transmission of 8 x 216.8 Gbit/s Nyquist-WDM signals over 1750 km with 21.6 dB average loss per span. Each channel, modulated by a 54.2 Gbaud PDM-CSRZ-QPSK signal, is on a 50 GHz grid, which produces a net spectral efficiency (SE) of 4 bit/s/Hz. We also describe mixed-data-rate transmission coexisting with 1T, 400G, and 100G channels. The 400G channel uses four independent subcarriers modulated by 28 Gbaud PDM-QPSK signals. This yields a net SE of 4 bit/s/Hz, and 13 optically generated subcarriers from a single optical source are used in the 1T channel with 25 Gbaud PDM-QPSK modulation. The 100G signal uses real-time coherent PDM-QPSK transponder with 15% overhead of soft-decision forward-error correction (SD-FEC). The digital post filter and 1 -bit maximum-likelihood sequence estimation (MLSE) are introduced at the receiver DSP to suppress noise, linear crosstalk, and filtering effects. Our results show that future 400G and 1T channels that use Nyquist WDM can transmit over long-haul distances with higher SE and using the same QPSK format. 展开更多
关键词 coherent detection field trial coherent optical OFDM Nyquist WDM MLSE
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Detection of biosignatures in Terrestrial analogs of Martian regions:Strategical and technical assessments 被引量:2
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作者 JianXun Shen Yan Chen +3 位作者 Yu Sun Li Liu YongXin Pan Wei Lin 《Earth and Planetary Physics》 EI CSCD 2022年第5期431-450,共20页
For decades, the search for potential signs of Martian life has attracted strong international interest and has led to significant planning and scientific implementation. Clearly, in order to detect potential life sig... For decades, the search for potential signs of Martian life has attracted strong international interest and has led to significant planning and scientific implementation. Clearly, in order to detect potential life signals beyond Earth, fundamental questions, such as how to define such terms as “life” and “biosignature”, have been given considerable attention. Due to the high costs of direct exploration of Mars, Mars-like regions on Earth have been invaluable targets for astrobiological research, places where scientists could practice the search for “biosignatures” and refine ways to detect them. This review summarizes scientific instrumental techniques that have resulted from this work. Instruments must necessarily be our “eyes” and “hands” as we attempt to identify and quantify biosignatures on Mars.Scientific devices that can be applied in astrobiology include mass spectrometers and electromagnetic-spectrum-based spectrometers,redox potential indicators, circular dichroism polarimeters, in situ nucleic acid sequencers, life isolation/cultivation systems, and imagers.These devices and how to interpret the data they collect have been tested in Mars-analog extreme environments on Earth to validate their practicality on Mars. To anticipate the challenges of instrumental detection of biosignatures through the full evolutionary history of Mars, Terrestrial Mars analogs are divided into four major categories according to their similarities to different Martian geological periods(the Early-Middle Noachian Period, the Late Noachian-Early Hesperian Period, the Late Hesperian-Early Amazonian Period, and the Middle-Late Amazonian Period). Future missions are suggested that would focus more intensively on Mars’ Southern Hemisphere, once landing issues there are solved by advances in spacecraft engineering, since exploration of these early terrains will permit investigations covering a wider continuum of the shifting habitability of Mars through its geological history. Finally, this paper reviews practical applications of the range of scientific instruments listed above, based on the four categories of Mars analogs here on Earth. We review the selection of instruments suitable for autonomous robotic rover tests in these Mars analogs. From considerations of engineering efficiency,a Mars rover ought to be equipped with as few instrument assemblies as possible. Therefore, once candidate landing regions on Mars are defined, portable suites of instruments should be smartly devised on the basis of the known geological, geochemical, geomorphological,and chronological characteristics of each Martian landing region. Of course, if Mars sample-return missions are successful, such samples will allow experiments in laboratories on Earth that can be far more comprehensive and affordable than is likely to be practicable on Mars.To exclude false positive and false negative conclusions in the search for extraterrestrial life, multiple diverse and complementary analytical techniques must be combined, replicated, and carefully interpreted. The question of whether signatures of life can be detected on Mars is of the greatest importance. Answering that question is extremely challenging but appears to have become manageable. 展开更多
关键词 BIOSIGNATURE detection framework extraterrestrial life evolutionary history of Mars field trial instrument Mars analog
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Recurrence-free survival as a putative surrogate for overall survival in phase Ⅲ trials of curative-intent treatment of colorectal liver metastases:Systematic review 被引量:1
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作者 Raphael LC Araujo Paulo Herman Rachel P Riechelmann 《World Journal of Clinical Oncology》 CAS 2017年第3期266-272,共7页
AIM To verify whether recurrence-free survival(RFS) surrogates overall survival(OS) in phase Ⅲ trials for resectable colorectal liver metastases(CRLM).METHODS MEDLINE,EMBASE,and Scopus databases were consulted.Eligib... AIM To verify whether recurrence-free survival(RFS) surrogates overall survival(OS) in phase Ⅲ trials for resectable colorectal liver metastases(CRLM).METHODS MEDLINE,EMBASE,and Scopus databases were consulted.Eligible studies were phase Ⅲ trials testing any type of systemic therapy(neoadjuvant,adjuvant or perioperative) added to surgery in patients with resectable CRLM.A linear regression model based on hazard ratios(HR) of OS and RFS was performed.RESULTS Of 3059 studies,5 phase Ⅲ trials(1162 patients) were included for analyses.A linear regression weighted by each trial was used to estimate the association between each HR and RFS.The originated formula was:OS HR =(0.93 × RFS HR) + 0.14;with RFS 95%CI(0.48-1.38),with P = 0.007.CONCLUSION This association suggests that RFS could work as a putative surrogate endpoint of OS in this population,avoiding bigger,longer and more resource-consuming trials.The OS could be assumed based on RFS and our model could be useful to better estimate sample size calculations of phase Ⅲ trials of CRLM aiming for OS. 展开更多
关键词 COLORECTAL liver METASTASES Surgery Chemotherapy Clinical trial long-term outcomes Surrogate ENDPOINTS
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Nitrogen mobility,ammonia volatilization,and estimated leaching loss from long-term manure incorporation in red soil 被引量:10
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作者 HUANG Jing DUAN Ying-hua +6 位作者 XU Ming-gang ZHAI Li-mei ZHANG Xu-bo WANG Bo-ren ZHANG Yang-zhu GAO Su-duan SUN Nan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第9期2082-2092,共11页
Nitrogen(N) loss from fertilization in agricultural fields has an unavoidable negative impact on the environment and a better understanding of the major pathways can assist in developing the best management practice... Nitrogen(N) loss from fertilization in agricultural fields has an unavoidable negative impact on the environment and a better understanding of the major pathways can assist in developing the best management practices. The aim of this study was to evaluate the fate of N fertilizers applied to acidic red soil(Ferralic Cambisol) after 19 years of mineral(synthetic) and manure fertilizer treatments under a cropping system with wheat-maize rotations. Five field treatments were examined: control(CK), chemical nitrogen and potash fertilizer(NK), chemical nitrogen and phosphorus fertilizer(NP), chemical nitrogen, phosphorus and potash fertilizer(NPK) and the NPK with manure(NPKM, 70% N from manure). Based on the soil total N storage change in 0–100 cm depth, ammonia(NH_3) volatilization, nitrous oxide(N_2O) emission, N plant uptake, and the potential N leaching loss were estimated using a mass balance approach. In contrast to the NPKM, all mineral fertilizer treatments(NK, NP and NPK) showed increased nitrate(NO_3~–) concentration with increasing soil depth, indicating higher leaching potential. However, total NH_3 volatilization loss was much higher in the NPKM(19.7%) than other mineral fertilizer treatments(≤4.2%). The N_2O emissions were generally low(0.2–0.9%, the highest from the NPKM). Total gaseous loss accounted for 1.7, 3.3, 5.1, and 21.9% for NK, NP, NPK, and NPKM treatments, respectively. Estimated N leaching loss from the NPKM was only about 5% of the losses from mineral fertilizer treatments. All data demonstrated that manure incorporation improved soil productivity, increased yield, and reduced potential leaching, but with significantly higher NH_3 volatilization, which could be reduced by improving the application method. This study confirms that manure incorporationis an essential strategy in N fertilization management in upland red soil cropping system. 展开更多
关键词 soil NO_3~–-N ammonia volatilization nitrogen leaching long-term field experiment mass balance nitrous oxide emission
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