The increasing demand for fresh sweet maize （Zea mays L. saccharata） in southern China has prioritized the need to find solutions to the environmental pollution caused by its continuous production and high inputs of...The increasing demand for fresh sweet maize （Zea mays L. saccharata） in southern China has prioritized the need to find solutions to the environmental pollution caused by its continuous production and high inputs of chemical nitrogen fertilizers. A promising method for improving crop production and environmental conditions is to intercrop sweet maize with legumes. Here, a three-year field experiment was conducted to assess the influence of four different cropping systems （sole sweet maize （SS）, sole soybean （SB）, two rows sweet maize-three rows soybean （S2B3） intercropping, and two rows sweet maize-four rows soybean （S2B4） intercropping）, together with two rates of N fertilizer application （300 and 360 kg N ha-1） on grain yield, residual soil mineral N, and soil N2O emissions in southern China. Results showed that in most case, inter- cropping achieved yield advantages （total land equivalent ratio （TLER=0.87-1.25） was above one）. Moreover, intercropping resulted in 39.8% less soil mineral N than SS at the time of crop harvest, averaged over six seasons （spring and autumn in each of the three years of the field experiment）. Generally, intercropping and reduced-N application （300 kg N ha-1） produced lower cumulative soil N20 and yield-scaled soil N20 emissions than SS and conventionaI-N application （360 kg N ha-l）, respectively. $2B4 intercropping with reduced-N rate （300 kg N ha-~） showed the lowest cumulative soil N20 （mean value=0.61 kg ha-1） and yield-scaled soil N20 （mean value=0.04 kg t-1） emissions. Overall, intercropping with reduced-N rate maintained sweet maize production, while also reducing environmental impacts. The system of S2B4 intercropping with reduced-N rate may be the most sustainable and environmentally friendly cropping system.展开更多
目的:对比cobas e 411电化学发光全自动免疫分析仪和贝克曼UniCel DxI 800化学发光仪在血清β-HCG以及孕酮检测中的应用价值。方法:纳入2021年1月~2021年6月于本院就诊的女性患者200例作为研究对象,经超声确诊将200例患者分成未孕组(n=1...目的:对比cobas e 411电化学发光全自动免疫分析仪和贝克曼UniCel DxI 800化学发光仪在血清β-HCG以及孕酮检测中的应用价值。方法:纳入2021年1月~2021年6月于本院就诊的女性患者200例作为研究对象,经超声确诊将200例患者分成未孕组(n=105)、早孕组(n=37)、异位妊娠组(n=58),对所有患者血液样本均进行贝克曼UniCel DxI 800化学发光仪和cobas e 411电化学发光全自动免疫分析仪检测,比较两种不同系统检测的血清β-HCG以及孕酮水平。结果:cobas e 411电化学发光全自动免疫分析仪检测下,未孕组患者、早孕组患者、异位妊娠组患者的血清β-HCG分别为:(2.91±0.40)mIU/mL、(31275.36±6138.43)mIU/mL、(180.39±80.65)mIU/mL,孕酮分别为:(1.72±0.78)nmol/L、(113.26±46.82)nmol/L、(13.05±7.04)nmol/L;贝克曼UniCel DxI 800化学发光仪检测下,未孕组患者、早孕组患者、异位妊娠组患者的血清β-HCG分别为:(2.90±0.42)mIU/mL、(30986.16±6149.79)mIU/mL、(180.47±79.82)mIU/mL,孕酮分别为:(1.73±0.79)nmol/L、(114.16±47.46)nmol/L、(13.13±7.10)nmol/L。未孕组、早孕组、异位妊娠组患者在通过两种检测系统检测下得到的血清β-HCG、孕酮结果组间比较差异均无统计学意义(P>0.05)。结论:通过cobas e 411电化学发光全自动免疫分析仪和贝克曼UniCel DxI 800化学发光仪对患者的血清β-HCG、孕酮结果进行检测,发现两种检测系统的准确性高,相关性良好,可以有效避免结果差异性给医生带来诊断困扰,得到的数据和临床要求均相符。展开更多
基金supported by the Key Technologies R&D Program of China during the 12th Five-year Plan period(2012BAD14B16-04)the Science and Technology Development Program of Guangdong,China(2012A020100003 and 2015B090903077)
文摘The increasing demand for fresh sweet maize （Zea mays L. saccharata） in southern China has prioritized the need to find solutions to the environmental pollution caused by its continuous production and high inputs of chemical nitrogen fertilizers. A promising method for improving crop production and environmental conditions is to intercrop sweet maize with legumes. Here, a three-year field experiment was conducted to assess the influence of four different cropping systems （sole sweet maize （SS）, sole soybean （SB）, two rows sweet maize-three rows soybean （S2B3） intercropping, and two rows sweet maize-four rows soybean （S2B4） intercropping）, together with two rates of N fertilizer application （300 and 360 kg N ha-1） on grain yield, residual soil mineral N, and soil N2O emissions in southern China. Results showed that in most case, inter- cropping achieved yield advantages （total land equivalent ratio （TLER=0.87-1.25） was above one）. Moreover, intercropping resulted in 39.8% less soil mineral N than SS at the time of crop harvest, averaged over six seasons （spring and autumn in each of the three years of the field experiment）. Generally, intercropping and reduced-N application （300 kg N ha-1） produced lower cumulative soil N20 and yield-scaled soil N20 emissions than SS and conventionaI-N application （360 kg N ha-l）, respectively. $2B4 intercropping with reduced-N rate （300 kg N ha-~） showed the lowest cumulative soil N20 （mean value=0.61 kg ha-1） and yield-scaled soil N20 （mean value=0.04 kg t-1） emissions. Overall, intercropping with reduced-N rate maintained sweet maize production, while also reducing environmental impacts. The system of S2B4 intercropping with reduced-N rate may be the most sustainable and environmentally friendly cropping system.
文摘目的:对比cobas e 411电化学发光全自动免疫分析仪和贝克曼UniCel DxI 800化学发光仪在血清β-HCG以及孕酮检测中的应用价值。方法:纳入2021年1月~2021年6月于本院就诊的女性患者200例作为研究对象,经超声确诊将200例患者分成未孕组(n=105)、早孕组(n=37)、异位妊娠组(n=58),对所有患者血液样本均进行贝克曼UniCel DxI 800化学发光仪和cobas e 411电化学发光全自动免疫分析仪检测,比较两种不同系统检测的血清β-HCG以及孕酮水平。结果:cobas e 411电化学发光全自动免疫分析仪检测下,未孕组患者、早孕组患者、异位妊娠组患者的血清β-HCG分别为:(2.91±0.40)mIU/mL、(31275.36±6138.43)mIU/mL、(180.39±80.65)mIU/mL,孕酮分别为:(1.72±0.78)nmol/L、(113.26±46.82)nmol/L、(13.05±7.04)nmol/L;贝克曼UniCel DxI 800化学发光仪检测下,未孕组患者、早孕组患者、异位妊娠组患者的血清β-HCG分别为:(2.90±0.42)mIU/mL、(30986.16±6149.79)mIU/mL、(180.47±79.82)mIU/mL,孕酮分别为:(1.73±0.79)nmol/L、(114.16±47.46)nmol/L、(13.13±7.10)nmol/L。未孕组、早孕组、异位妊娠组患者在通过两种检测系统检测下得到的血清β-HCG、孕酮结果组间比较差异均无统计学意义(P>0.05)。结论:通过cobas e 411电化学发光全自动免疫分析仪和贝克曼UniCel DxI 800化学发光仪对患者的血清β-HCG、孕酮结果进行检测,发现两种检测系统的准确性高,相关性良好,可以有效避免结果差异性给医生带来诊断困扰,得到的数据和临床要求均相符。
