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Mechanisms of Enhanced Rice Growth and Nitrogen Uptake by Nitrate

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Pedosphere 2007年第6期17卷 697-705页

作者： DUAN ying-Hua yin xiao-ming ZHANG Ya-Li SHEN Qi-Rong College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China）

Rice is being increasingly cultivated in intermittently irrigated regions and also in aerobic soil in which Nitrate （NO3^- ） plays important role in nutrition of plant. However, there is no information regarding the influence of nitrate on the overall growth and uptake of nitrogen （N） in rice plant. Solution culture experiments were carried out to study the effects of NO^3- on the plant growth, uptake of N, and uptake kinetics of NH4^＋ in four typical rice （Oryza sativa L.） cultivars （conventional indica, conventional japonica, hybrid indica, and hybrid japonica）, and on plasma membrane potential in roots of two conventional rice cultivars （indica and japonica） at the seedling stage. The results obtained indicated that a ratio of 50/50 NH4^＋-N/NO3^--N increased the average biomass of rice shoots and roots by 20% when compared with that of 100/0 NH4^＋-N/NO3^--N. In case of the 50/50 ratio, as compared with the 100/0 ratio, total N accumulated in shoots and roots of rice increased on an average by 42% and 57%, respectively. Conventional indica responds to NO3^- more than any other cultivars that were tested. The NO^3- supply increased the maximum uptake rate （Vmax） of NH4^＋ by rice but did not show any effect on the apparent Michaelis-Menten constant （Km） value, with the average value of Vmax for NH4^＋ among the four cultivars being increased by 31.5% in comparison with those in the absence of NO3^-. This suggested that NO3^- significantly increased the numbers of the ammonium transporters. However, the lack of effect on the Km value also suggested that the presence of NO3^- had no effect on the affinity of the transporters for NH4^＋. The plasma membrane potential in the roots of conventional indica and japonica were greatly increased by the addition of NO3^- , suggesting that NO3^- could improve the uptake of N by roots of the rice plant. In conclusion, the mechanisms by which NO3^- enhances the growth and N uptake of rice plant was found by the increased value of Vm

关键词： ammonium uptake nitrate nutrition nitrogen uptake plasma membrane potential rice

Signal transduction mediated by Bid, a pro-death Bcl-2 family proteins, connects the death receptor and mitochondria apoptosis pathways

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Cell Research 2000年第3期10卷 161-167页

作者： yin xiao-ming (Department of Pathology, University of Pittsburgh School of Medicine, 3550 Terrace Street, Pittsburgh, PA 15261, USA) DepartmentofPathology UniversityofPittsburghSchoolofMedicinePA15261USA.xmyin@pitt.edu

Two major apoptosis pathways have been defined in mammalian cells, the Fas/TNF-R1 death receptor pathway and the mitochondria pathway. The Bcl-2 family proteins consist of both anti-apoptosis and pro- apoptosis members that regulate apoptosis, mainly by controlling the release of cytochrome c and other mitochondrial apoptotic events. However, death signals mediated by Fas/TNF-R1 receptors can usually activate caspases directly, bypassing the need for mitochondria and escaping the regulation by Bcl-2 family proteins. Bid is a novel pro-apoptosis Bcl-2 family protein that is activated by caspase 8 in response to Fas/TNF-R1 death receptor signals. Activated Bid is translocated to mitochondria and induces cytochrome c release, which in turn activates downstream caspases. Such a connection between the two apoptosis pathways could be important for induction of apoptosis in certain types of cells and responsible for the pathogenesis of a number of human diseases.

关键词： Apoptosis Bcl-2 family proteins Bid Fas TNF.

Distribution of Mineral Nutrients and Active Ingredients in Aloe vera Irrigated with Diluted Seawater

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Pedosphere 2014年第6期24卷 722-730页

作者： JIANG Chao-Qiang QUAN Ling-Tong SHI Feng YANG Na WANG Chang-Hai yin xiao-ming ZHENG Qing-Song College of Resources and Environmental Science Key Laboratory of Marine BiologyNanjing Agricultural University Tobacco Research Institute Anhui Academy of Agricultural Science College of Life Science Nanjing Agricultural University

With increasing demand for irrigation water, agricultural scientists and planners pay more attention to the utilization of diluted seawater as an alternative source for irrigation of crops. A greenhouse pot experiment was conducted to study how seawater stress(SS) affects growth, water content, cationic accumulation, and active ingredients in leaves of Aloe vera after 30 d of growth in nutrient media with 0%(control), 22%(22% SS), and 42%(42% SS) seawater stress. Results indicated the SS did not change dry biomass of leaves and stems, but gradually decreased biomass allocation to roots with increasing seawater stress. Na+and Cl-in A. vera plant did not increase obviously with a big increase in seawater percentage due to low transpiration of Aloe vera. 42% SS decreased N concentration in most plant organs, but did not change or increased P concentration. Seawater stress tended to decrease concentrations of K+and Ca2+in A. vera. However, seawater salinity tended to increase the concentrations of aloin concentration in top(young) and middle leaves, and there was no significant effect of both stresses on aloin concentration in base(old) leaves. The 42% SS treatment decreased polysaccharide concentrations only in the base leaves, but not in top and middle leaves. In summary, supplying suitably diluted seawater for 30 d could increase the qualities and value of A. vera, without substantial effects on shoot dry biomass production.

关键词： aloin growth nutrition distribution polysaccharide seawater irrigation

单磁场驱动的Tb_(1-x)Dy_xFe_(2-y)/Pb(Zr,Ti)O_3三层膜磁电效应

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物理学报 2008年第9期57卷 5951-5955页

作者：印晓明张宁南京师范大学磁电子学实验室南京210097

研究了Tb1-xDyxFe2-y(TDF)与锆钛酸铅(PZT)三层膜样品的制备和在单一直流磁场驱动下的磁电(ME)效应.在该系列三层膜样品中测量到了巨大的ME耦合效应.所得实验结果与同种样品在两磁场驱动下的ME效应完全不同.这可能预示了某些新的物理内... 详细信息

研究了Tb1-xDyxFe2-y(TDF)与锆钛酸铅(PZT)三层膜样品的制备和在单一直流磁场驱动下的磁电(ME)效应.在该系列三层膜样品中测量到了巨大的ME耦合效应.所得实验结果与同种样品在两磁场驱动下的ME效应完全不同.这可能预示了某些新的物理内容.该技术可简化ME效应在某些实际应用中的复杂度.

关键词： Tb1-xDyxFe2-y PZT 单磁场 ME效应

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一种改进的T-S模糊模型建模及优化方法

华东理工大学学报（自然科学版） 2016年第2期42卷 233-239页

作者：刘骏殷晓明顾幸生华东理工大学化工过程先进控制与优化技术教育部重点实验室上海200237

模糊建模是一种有效的非线性系统建模方法,因为非线性系统的复杂性,仍有很多问题难以处理。针对T-S模糊模型,提出了一种改进的建模及优化方法。首先,将快速搜索密度峰聚类和模糊C均值聚类(FCM)算法相结合,使用快速搜索密度峰聚类算法找... 详细信息

模糊建模是一种有效的非线性系统建模方法,因为非线性系统的复杂性,仍有很多问题难以处理。针对T-S模糊模型,提出了一种改进的建模及优化方法。首先,将快速搜索密度峰聚类和模糊C均值聚类(FCM)算法相结合,使用快速搜索密度峰聚类算法找到聚类个数和初始聚类中心后,再用FCM算法进行聚类;然后,通过最小二乘法辨识结论参数得到初始T-S模糊模型,使用改进的差分进化(DE)算法整体优化模型的结构和参数,获得最终的T-S模型;最后,选择代表性实例,使用MATLAB程序进行仿真分析和比较,验证了本文方法能有效提高T-S模糊模型的辨识精度和速度。

关键词：模糊建模 T-S模型模糊C均值聚类快速搜索密度峰聚类差分进化算法

单磁场驱动的Tb_(1-x)Dy_xFe_(2-y)-Pb(Zr,Ti)O_3-Tb_(1-x)Dy_xFe_(2-y)三层膜磁电效应

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功能材料与器件学报 2008年第3期14卷 692-696页

作者：印晓明张宁南京师范大学磁电子学实验室南京210097

研究了Tb1-xDyxFe2-y(TDF)与锆钛酸铅(PZT)三层膜样品的制备和在单一直流磁场驱动下的磁电(ME)效应。在该系列三层膜样品中测量到了巨大的ME耦合效应,纵向场中,ME电压的最大变化范围可达1404V/cm。所得实验结果与同种样品的两磁场驱动... 详细信息

研究了Tb1-xDyxFe2-y(TDF)与锆钛酸铅(PZT)三层膜样品的制备和在单一直流磁场驱动下的磁电(ME)效应。在该系列三层膜样品中测量到了巨大的ME耦合效应,纵向场中,ME电压的最大变化范围可达1404V/cm。所得实验结果与同种样品的两磁场驱动的ME效应完全不同。这可能预示了某些新的物理内容。该技术可简化ME效应在某些实际应用中的复杂度。

关键词： ME效应三层膜 Tb1-xDyxFe2-y 单磁场

中美高中主流物理教材科学素养主题编排的比较

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当代教育与文化 2020年第4期12卷 45-49页

作者：印晓明陈坤江苏省南菁高级中学教科室江苏无锡214437 江苏省南菁高级中学江苏无锡214437

教材是学科科学思想、科学知识、科学方法和科学品德的载体。以提升学生的科学素养为目标,对中美两国主流物理教材的章节内容、栏目设置、实验编排、插图设计等进行比较研究,统整两国教材的特色、优势,提出物理课程中培育学生科学素养... 详细信息

教材是学科科学思想、科学知识、科学方法和科学品德的载体。以提升学生的科学素养为目标,对中美两国主流物理教材的章节内容、栏目设置、实验编排、插图设计等进行比较研究,统整两国教材的特色、优势,提出物理课程中培育学生科学素养的着力点:关注知识的整体建构、恢复知识的实践属性、重视科学学科间的融合;具体可沿"通过核心概念学习科学知识、开展真实探究掌握科学方法、联系生活实际培养应用能力、还原科研历史弘扬科学精神"等路径开展教学探索;挑选"思维力"的培养作为切入点,以关键素养的培育带动学生整体科学素养的提升。

关键词：中美教材比较物理课程科学素养科学思维

Synthesis and Structural Characterization of Pd[CH3O（O）C6H3CHNNC（S）NH2]（C5H5N）

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Chinese Journal of Structural Chemistry 2003年第2期 200-202页

作者： ZI Feng-Lan ZHOU yin-Zhuang② LU xiao-ming LIU Shun-Cheng (Department of Chemistry, Capital Normal University, Beijing 100037, China) JIN Xiang-Lin (Institute of Physical Chemistry, Beijing University, Beijing 100871, China)

The reaction of palladium chloride with isovanillin semithiocarbazone (VSTC), CH3O(OH)C6H3CH=NNC(S)NH2, in a mixed solvent of ethanol, pyridine and water yielded the mononuclear palladium(Ⅱ) complex Pd[CH3O(O)C6H3CHNNC(S)NH2](C5H5N), and its single- crystal structure was determined by X-ray diffraction. The crystal belongs to triclinic, space group P with a = 7.715(4), b = 9.809(6), c = 10.612(4) ? a = 93.54(4), b = 111.00(3), g = 95.92(5), V = 745.0(7) 3, Mr = 408.75, Z = 2, Dc = 1.822 g/cm3, m = 1.397 mm-1, and F(000) = 408. The final R = 0.0568 and wR = 0.1439 for 2616 observed independent reflections with I ≥ 2.0s(I). It was revealed that the palladium atom is bound to a tridentate donor ligand and a pyridine in a planar square arrangement. The sulphur-nitrogen-oxygen donor of the Schiff-base ligand in the thiol form rather than the thione one is coordinated to the palladium atom via the mercapto sulphur, the b-nitrogen and the hydroxylate oxygen atoms.

关键词： palladium(Ⅱ) complex Schiff base crystal structure

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猪粪堆肥过程中养分和重金属含量的动态变化

植物营养与肥料学报 2019年第2期25卷 254-263页

作者：尹晓明王荣江徐潇潇曹云南京农业大学资源与环境科学学院江苏南京210095 江苏省农科院农业资源与环境研究所江苏南京210095

【目的】规模化、集约化畜禽养殖业饲料中,存在滥用或超剂量使用微量元素如Cu、Zn、Fe、As添加剂的现象,导致畜禽粪便以及以畜禽粪便为来源的有机肥重金属的积累。研究堆肥过程中养分和重金属含量的动态变化,对于畜禽粪便有机肥产业的... 详细信息

【目的】规模化、集约化畜禽养殖业饲料中,存在滥用或超剂量使用微量元素如Cu、Zn、Fe、As添加剂的现象,导致畜禽粪便以及以畜禽粪便为来源的有机肥重金属的积累。研究堆肥过程中养分和重金属含量的动态变化,对于畜禽粪便有机肥产业的可持续发展具有重要意义。【方法】鲜猪粪在阴凉通风处风干到含水率在60%左右,用于进行55天的好氧堆肥。猪粪∶砻糠比例为6∶1 (鲜重)混匀,每周翻堆一次,每天测定温度,分别在堆肥第1、13、23、28、41和55天的上午10:00—11:00,取样测定含水量、pH值、全氮、总有机碳(TOC)、全磷、全钾以及Cr、Cd、Cu、Mn、Ni、Zn、Pb、Hg、As总量和有效态Cu、Mn、Zn含量。【结果】1)随着堆沤进程的延长,全氮先升高再下降,其峰值出现在第23～28天,之后缓慢下降;全磷与全钾逐渐升高,其峰值均在第41天、之后趋于稳定;TOC不断减少,28天以后趋于平稳。C/N先下降,第23天以后保持稳定,堆肥结束时维持在15.12、达到腐熟要求。2) 9种金属元素的总量变化各不相同,含量分别为Cr6.99～10.43 mg/kg、Cu 106.01～120.81 mg/kg、Mn 663.51～899.48 mg/kg、Ni 11.32～20.67 mg/kg、Zn1245.18～1552.13 mg/kg、Pb 0.09～0.56 mg/kg、As 0.58～1.25 mg/kg,Cd、Hg未检测出。Cr和Ni先下降、升高、再下降直至平稳,其峰值均在第23天,第28天以后趋于平稳。Cu、Mn和Zn不断升高到后期显著升高、其峰值均在第41天。As先下降再升高、在第28天以后基本平稳。Pb总体是下降,在第13天和23天其含量分别比第1天显著下降61.22%和81.63%,在第41天以后其含量未检出。有效Cu、Mn、Zn的含量远低于元素总量,分别在2.35～5.79 mg/kg、17.82～20.28 mg/kg和47.39～70.29 mg/kg。有效Cu、有效Zn总体先升高、再下降直至平稳,峰值都在第13～23天,第28天显著下降但是此后基本平稳。有效Mn总体变化不大,只在第41天显著上升。3)有效Cu与有效Zn、有效Zn与有效Mn之间呈极显著正相关关系。全钾、全磷、Cu、Zn、Mn与TOC之间呈极显著负相关关系(P <0.01),说明全钾、全磷、Cu、Zn与Mn含量的升高由堆肥过程中有机质的矿化引起。而有效Cu、有效Zn、有效Mn与TOC不存在相关关系。【结论】从23天到28天,高温的平均温度和持续时间符合畜禽粪便无害化的要求,C/N和全氮都维持在相对理想的水平,大量元素、微量元素和重金属含量基本达到稳定,表明28天是堆肥腐熟的关键时间节点。

关键词：猪粪堆肥养分重金属动态变化