Ciliary orientation: controlled by cell membrane or by intracellular fibrils?

The cirri of the ciliate Euplotes all asslumne the "reversed" orientation whenever the cell is depolarized and the "forward" orientation whenever the cell is hyperpolarized. Potenitial changes arise spontaneolusly or are induced by electrical or mechanical stimuli. The orientation responses of thte cirri are appatently independent of intracellular "neuromotor" fibrils previously assigned a coordinating function, as they persist after the fibrils are transected.     

An examination of "transfer of learning" by nucleic Acid

Nucleic acid extracted from brains of trained animals and injected intraperitoneally into naive animals produced no "transfer of learning" effect on several tasks under many conditions. P(325)-Labeled RNA was not found in the brain after intraperitoneal administration. Even intraventricular injections of nucleic acid produced no "transfer" effect.     

Memory Glass: An Amorphous Material Formed from AlPO4

A glass exhibiting structural memory has been produced through the compression of a single crystal of AlPO(4) berlinite to 18 gigapascals at 300 kelvin. The unique and extraordinary characteristic of this glass is that upon decompression below 5 gigapascals it transforms back into a single crystal with the same orientation as the starting crystal. This glass has a "memory" of the previous crystallographic orientation of the crystal from which it forms.     

“后合作社法时代”农民合作的理论和实践方向

在回顾建国后农民经济合作三个发展阶段的基础上,提出“后合作社法时代”的概念;指出“后合作社法时代”农民合作的理论研究方向和实践工作方向。     

“以人为本”理念下的高校新生入学教育

分析了"以人为本"理念与新生入学教育的关系,提出了"以人为本"为高校新生入学教育提供指导作用,是适应时代发展和提高时效性的需要,就如何完善"以人为本"理念下的高校新生入学教育展开探讨,提出要强化"以人为本"的新生入学教育理念和构建"以人为本"的入学教育新体系。     

红松一年生苗木根系生长发育动态的研究

１９９２年在东北林业大学帽儿山实验林场苗圃,采用定位挖掘法研究了红松一年生苗木根系的季节生长发育动态。结果表明;（１）主根生长呈“Ｓ”型曲线,在种壳即将脱去时长速度最大;（２）在脱壳期,当子叶暴露部分超过其自身长度一半时,在主根木栓化区域产生一级侧根根原基突起;一级侧根总长度生长呈“Ｓ”型曲线,其峰值在真叶基本结束生长的８月下旬;（３）在幼苗高生长基本结束并形成顶芽时,在一级侧根上产生二级侧根根原     

土壤湿度估计的理想同化试验研究

通过使用集合Kalman滤波,建立基于不同离散化方法的同化土壤湿度的理想试验。通过设置不同的初始状态,以集合预报的形式建立了openloop和模拟的理想＂真值＂,并将来自不同离散化方法得到的理想＂真值＂集合生成多模型集合预报的理想＂真值＂。分别使用单个的离散化方法同化来自各自理想＂真值＂和多模型集合预报的理想＂真值＂,来检验通过同化表层土壤湿度后对整个湿度廓线的改进能力。结果表明,由于不同的离散化方法建立的土壤层之间的相关性不同,不同的离散化方法通过同化表层土壤湿度后土壤湿度廓线均有改进,但是改进的效率不同;当使用多模型的集合预报时,能够更有效地吸收观测,比任何单个模型的同化效果都要好。     

Ceramic thin-film formation on functionalized interfaces through biomimetic processing

Processing routes have been developed for the production of thin ceramic films through precipitation from aqueous solutions. The techniques are based on crystal nucleation and growth onto functionalized interfaces. Surface functionalization routes have been developed by the mimicking of schemes used by organisms to produce complex ceramic composites such as teeth, bones, and shells. High-quality, dense polycrystalline films of oxides, hydroxides, and sulfides have now been prepared from "biomimetic" synthesis techniques. Ceramic films can be synthesized on plastics and other materials at temperatures below 100 degrees C. As a low-temperature process in which water rather than organic solvents is used, this synthesis is environmentally benign. Nanocrystalline ceramics can be produced, sometimes with preferred crystallite orientation. The direct deposition of high-resolution patterned films has also been demonstrated. The process is well suited to the production of organic-inorganic composites.     

Amnesia produced by electroconvulsive shock or cycloheximide: conditions for recovery

Retrograde amnesia for a passive avoidance response was produced in rats by electroconvulsive shock and in mice by cycloheximide, an inhibitor of protein synthesis. One day after training the memory could be restored if a "reminder" of the original foot shock was given after the retention test on which the amnesia was demonstrated. Memory did not return if the reminder was given without the prior retention test or if the reminder and the test were separated by 23 hours.     

农业科研单位党建工作与科研业务融合促进对策

农业科研单位是深入实施乡村振兴战略的重要科技支撑力量,而加强党的建设是增强农业科研单位向心力和凝聚力的重要保证。文章针对当前党建工作与科研业务“两张皮”的问题,分析其产生原因,并以“目标导向、治理导向、人才导向”为切入点,探讨如何加强党的建设,以期实现党建工作与科研业务双促双融的目的。     

退火处理对葛根淀粉老化特性和质构特性的影响

采用差式量热扫描仪(DSC)、低场核磁共振分析仪和质构分析仪研究退火处理对葛根淀粉老化过程中水分迁移、老化特性和质构特性的影响。结果表明,退火处理会使葛根淀粉在老化过程中的水分子相对含量降低;退火时间对葛根淀粉老化度的影响较为明显,随着退火时间的延长,葛根淀粉的糊化焓增加,老化焓降低,老化度降低,当退火时间达到24 h时,葛根淀粉老化1 d后的老化度从原葛根淀粉的32.95%降到19.58%,老化10 d后的老化度从37.42%降到19.46%;原葛根淀粉凝胶和退火处理葛根淀粉凝胶的凝胶强度随着时间的延长而增大,当退火时间达到24 h时,老化1 d后的凝胶强度从原葛根淀粉的27.34增加到48.44,老化10 d后的凝胶强度从72.11增加到76.45,弹性则随着时间的延长而减小。     

基于农用地分等更新的基本农田规划问题研究(英文)

以A市B区为例,在农用地分等更新的基础上,评价规划划定基本农田的质量。分析表明,不考虑农用地分等更新本轮规划划定基本农田利用等为16.82等,考虑农用地分等更新后基本农田利用等提高了0.08等,但仍比上轮规划降低了0.11等。最后,分析了本轮规划划定基本农田存在问题的原因,一是城市发展定位对基本农田保护考虑不足;二是土地利用总体规划忽视对基本农田质量的检查;三是土地整理后优质耕地未划入基本农田保护区;四是农用地分等成果更新不及时。并提出了解决对策:在土地利用总体规划中加强对基本农田质量的考虑;将土地整理后的优质耕地优先划入基本农田;及时进行农用地分等更新,将农用地分等成果纳入"一张图"工程。     

Skin sensory afterglows

Brief stimulation of the upper lip with the tip of a nylon thread frequently produces an " afterglow" sensation that may persist as long as several minutes after cessation of stimulation. The duration of afterglow is increased by strong suggestion, and decreased by vibration of the skin prior to stimulation. The afterglow may be followed by a period of acute "awareness" of the area, distincty different from the stimulus and afterglow sensations. The afterglows produced by a warm stimulator applied to the back often well up into a painful sting.     

管道阴极保护死区腐蚀分析及控制

针对我国目前长输管道腐蚀现状,介绍了在防腐层和外加强制电流阴极保护这种表观有效的双重保护体系下,管道发生的一种腐蚀现象,即阴极保护死区腐蚀,阐述了形成阴极保护死区和产生腐蚀的原因,结合阴极保护死区腐蚀的特点分析了腐蚀发生的机理,提出了在实际工作中减轻阴极保护死区腐蚀的有效措施。     

Transient and stable expression of the firefly luciferase gene in plant cells and transgenic plants

The luciferase gene from the firefly, Photinus pyralis, was used as a reporter of gene expression by light production in transfected plant cells and transgenic plants. A complementary DNA clone of the firefly luciferase gene under the control of a plant virus promoter (cauliflower mosaic virus 35S RNA promoter) was introduced into plant protoplast cells (Daucus carota) by electroporation and into plants (Nicotiana tabacum) by use of the Agrobacterium tumefaciens tumor-inducing plasmid. Extracts from electroporated cells (24 hours after the introduction of DNA) and from transgenic plants produce light when mixed with the substrates luciferin and adenosine triphosphate. Light produced by the action of luciferase was also detected in undisrupted leaves or cells in culture from transgenic plants incubated in luciferin and in whole transgenic plants "watered" with luciferin. Although light was detected in most organs in intact, transgenic plants (leaves, stems, and roots), the pattern of luminescence appeared to reflect both the organ-specific distribution of luciferase and the pathway for uptake of luciferin through the vasculature of the plant.     

Generalized tube model of biased reptation for gel electrophoresis of DNA

A theoretical analysis of the reptational motion of DNA in a gel that includes the effects of molecular fluctuations has been used to explain the main features found in experiments involving periodic inversion of the electric field. The resonance-like decrease of the electrophoretic mobility as a function of pulse duration is related to transient "undershoots" in the orientation of the molecule, in agreement with recent experimental data. These features arise from a delicate interplay of internal and center of mass motion of the molecules under pulsed field conditions, and are important for the separation of DNA molecules in the size range 0.2 to 10 million base pairs.     

我国农业功能拓展的多重约束与历史机遇研究

分析了农业功能拓展的原因,论述了我国农业多功能的定位和发挥受多重制约条件的限制而存在多方面的失调和扭曲,指出进入工业化中期阶段后,我国农业功能拓展出现了多方面的发展机遇。     

杂交高粱株型和产量性状间的典范相关分析

本文用典范相关分析方法研究了杂交高粱株型性状与产量性状间的关系。结果表明:株高、叶向值与穗粒数、千粒重之间的典范相关系数为0.6365(P<0.05),相关信息比为67.27％;并在第一对典范相关变量的回归直线V_1=0.6365u_1上按各组合点间的亲疏关系把供试的23个组合划分为四类,类内各组合的产量差异不显著,而类间差异达显著或极显著水平;今后应把叶向值列为高梁理想株型育种的主要性状。     

农杆菌介导获得转淀粉分枝酶基因rbe1籼稻

用农杆菌介导法获得转淀粉分枝酶基因(rbe1)水稻珍汕97B、 -32B,恢复系明恢86、明恢81和航1号.分子检测表明,rbe1已经整合到籼稻的染色体中;对转基因水稻后代遗传分离进行分析,获得初步结果.