老年痴呆与血浆同型半胱氨酸水平关系的临床研究

目的:探讨血浆同型半胱氨酸(homocysteine,Hcy)水平与老年痴呆的相关性。方法:应用全自动生化分析仪以循环酶法检测90例老年痴呆患者的血浆Hcy浓度,并与30例非痴呆患者作为同龄对照组血浆Hcy浓度进行比较;根据Hachinski缺血指数量表评分将老年痴呆分为阿尔茨海默病(Alzheimer’s disease,AD),混合性痴呆(mixed dementia,MD),血管性痴呆(vascular dementia,VD);根据简易精神状态检查量表(Mini-Mental State Examination,MMSE)评分划分痴呆患者严重程度,分为轻度、中度、重度。结果:AD、MD、VD组血浆Hcy水平均显著高于对照组(P<0.01);不同程度痴呆患者血浆Hcy水平有显著性差异(P<0.05),血浆Hcy浓度越高,认知功能损害的程度越重。结论:高Hcy血症可能是老年期痴呆发病的一个重要危险因素,且认知功能减退的程度与血浆同型半胱氨酸浓度呈正相关。     

重度盐碱地营造杨树人工林土壤改良效果

为探讨重度盐碱地营造杨树人工林对土壤的改良效果,本实验以黑龙江省肇东市重度盐碱地作为研究对象,采用小穴改良"一字沟"觅食丘式原位修复、小穴改良"十字沟"觅食台式原位修复和小穴改良"井字沟"觅食坛式原位修复的方法对重度盐碱地进行改良。研究结果表明:实施不同改良措施后土壤特性发生了显著变化,土壤pH值、电导率含量显著下降;土壤碳酸根含量显著下降,交换性钙、镁含量显著提高;土壤胡敏酸和壳聚糖含量明显提高,土壤肥力增加。因此,本研究所采用的三种不同的改良措施具有良好的改良效果。     

盐碱地土壤微生物对不同改良方法的响应

实验室条件下分别模拟客土改良、排水改良、生物(苜蓿)改良等3种常用的盐碱地改良方法,以菜园土壤和盐碱土(未改良的原始土)作为对照,研究了土壤微生物生态特征对不同改良方法的响应。结果显示:①土壤微生物区系及生理生化指标均对不同改良方式有良好的响应,其中土壤脲酶活性随土壤盐碱胁迫加剧而提高;②3种改良方式中,客土法在短期内最能改善土壤微生物各指标,依次是排水法、生物法;③排水法对土壤微生物生态状况不利;④生物法对于改善土壤微生物生态状况速度相对较慢,但因其克服了客土法、排水法显见的缺点,相对有更好的应用前景。     

Influences of addition of different krilium in saline-sodic soil on the seed germination and growth of cabbage

China is one of the largest countries with huge amount of saline-sodic soil. How to ameliorate these lands is a hotspot in China. Through measurement of soil salinity, pH value and seed germination and growth status of cabbage seedlings, 17 kinds of krilium were added to experimented soil to evaluate their effects on amelioration of heavy saline-sodic soil. Firstly, among these 17 kinds of krilium, 11 (HPMA, gypsum, HEDP, T225, PAPEMP, MA-AA, ATMP, AA/AMPS, PAA, charcoal and BHMTPMPA) were effective agents and could effectively induce seed germination without any germination phenomena in the control saline-sodic soil. HPMA was the best one in ameliorating saline-sodic soil, which has been manifested by various indices of seed germination. Secondly, addition of gypsum together with other organic agents could strongly increase the ameliorative effectiveness if compared with relatively weak agents, while decrease seed germination if compared with the stronger agent of the 2 mixed agents, showing that the synergetic effect between gypsum and other kinds of tested krilium was not evident. Thirdly, optimum dosages for separate addition of HPMA and gypsum were 42.8 L m^?3 and 25 kg m^?3, while mixed-addition of these 2 agents at the same dosages did not cause plus effect in soil improvement. Finally, field application of HPMA could enhance the growth of cabbage seedlings at the first month, but began to wilt thereafter. Thus, instead of one-time addition, several-time addition of HPMA at the suitable dosage in field practice could strengthen the effectiveness of soil amelioration.     

Hierarchical Categorical Perception in Sensing and Cognitive Processes

This article considers categorical perception (CP) as a crucial process involved in all sort of communication throughout the biological hierarchy, i.e. in all of biosemiosis. Until now, there has been consideration of CP exclusively within the functional cycle of perception–cognition–action and it has not been considered the possibility to extend this kind of phenomena to the mere physiological level. To generalise the notion of CP in this sense, I have proposed to distinguish between categorical perception (CP) and categorical sensing (CS) in order to extend the CP framework to all communication processes in living systems, including intracellular, intercellular, metabolic, physiological, cognitive and ecological levels. The main idea is to provide an account that considers the heterarchical embeddedness of many instances of CP and CS. This will take me to relate the hierarchical nature of categorical sensing and perception with the equally hierarchical issues of the “binding problem”, “triadic causality”, the “emergent interpretant” and the increasing semiotic freedom observed in biological and cognitive systems.

Targeted disruption of the Pak5 and Pak6 genes in mice leads to deficits in learning and locomotion

PAK6 is a member of the group B family of PAK serine/threonine kinases, and is highly expressed in the brain. The group B PAKs, including PAK4, PAK5, and PAK6, were first identified as effector proteins for the Rho GTPase Cdc42. They have important roles in filopodia formation, the extension of neurons, and cell survival. Pak4 knockout mice die in utero, and the embryos have several abnormalities, including a defect in the development of motor neurons. In contrast, Pak5 knockout mice do not have any noticeable abnormalities. So far nothing is known about the biological function of Pak6. To address this, we have deleted the Pak6 gene in mice. Since Pak6 and Pak5 are both expressed in the brain, we also generated Pak5/Pak6 double knockout mice. These mice were viable and fertile, but had several locomotor and behavioral deficits. Our results indicate that Pak5 and Pak6 together are not required for viability, but are required for a normal level of locomotion and activity as well as for learning and memory. This is consistent with a role for the group B PAKs in the nervous system.     

The Cognitive Enhancer SGS742 Does not Involve Major Known Signaling Cascades in OF1 Mice

In a previous study we have shown that SGS742, a cognitive enhancer acting by GABA(B) receptor antagonism improved spatial learning in OF1 mice. The aim of the study was therefore to screen representatives of several signaling cascades known to be involved in memory formation at the protein level. NaCl-, SGS742- treatment and yoked controls for NaCl and SGS742 were studied. Six hours following testing OF1 mice in the Morris water maze, hippocampal signaling proteins calmodulin kinase II (CaMKII) (phosphorylated (P) and non-phosphorylated (NP) form), CREB (P, NP), ERK (P, NP), BDNF, Egr-1, Trk-B and neuro-cytoskeleton elements drebrin and PSD-95 were determined by immunoblotting. Protein patterns were comparable between the control and SGS742 treated group revealing that these proteins may not be involved in the mechanisms underlying cognitive enhancement by SGS742 and this should be taken into account for interpretation and design of previous and future related neurochemical studies.     

On the role of emotion in biological and robotic autonomy

This paper reviews some of the differences between notions of biological and robotic autonomy, and how these differences have been reflected in discussions of embodiment, grounding and other concepts in AI and autonomous robotics. Furthermore, the relations between homeostasis, emotion and embodied cognition are discussed as well as recent proposals to model their interplay in robots, which reflects a commitment to a multi-tiered affectively/emotionally embodied view of mind that takes organismic embodiment more serious than usually done in biologically inspired robotics.     

植物残茬对土壤酸度的影响及其作用机理

土壤强酸性是作物生长的最主要限制因子之一,某些植物残茬可以有效地提高土壤pH,降低活性铝含量,提高作物产量。植物残茬改良土壤酸度的效能因种而异,最高土壤pH升幅可达4.53个单位,多种豆科植物材料可使土壤pH提高2个单位以上,当pH>5时,土壤溶液活性铝降至极低水平,从而消除铝害。植物残茬改良土壤酸度的效能受植物残茬自身特性与土壤特性的影响,而且pH的上升通常在几个月后消失,但这种效能对当季作物有效。植物体内有机酸根的去羧化作用被认为是pH上升的主要机理之一,去羧化机理存在的主要证据是,随着土壤pH升高,植物材料内的可溶性有机成分下降,CO2排放与pH上升高度相关,以及杀菌条件下土壤pH上升速度显著减慢。超量碱机理是植物残茬导致pH上升的又一可能的重要机理,亦即有机盐的作用,有机盐分解转化为碳酸盐,其作用与石灰完全相似,有机盐水解也可导致土壤溶液的碱性反应。铵化作用与硝化作用是高氮植物材料影响土壤酸度的重要机理,有机氮的铵化直接消耗质子,铵的硝化则产生质子,pH的变化与这些氮过程高度相关。含硫植物材料及有机物质分解过程产生的氧化还原条件的变化,也可对土壤pH产生影响,但它们的作用较小。综合来看,去羧化作用机理基于间接证据,没有得到严格验证,超量碱机理可能是土壤pH上升的主要原因,超量碱只能转移,不能制造,含超量碱高的外源性有机材料施入耕地,将是改良土壤酸度,提高作物产量的一种有效途径。     

小长梁石工业研究

根据小长梁遗址1998年和1990-1997年间5次发掘所获得的石制品,本文采用操作链（chaine opera-toire)分析概念,从石料、打制技术,二次加工、微痕观察,废片分析和认知考古学的角度,对小长梁石工业的结构及所反映的人类行为和智慧进行了综合分析。分析表明,小长梁石工业受劣质石料的影响很大,碎屑块比例极高,打片技术简单,仅采用锤击和砸击法,二次加工制品比例很低,不存在概念型板的规范制品,微痕分析显示,遗址的经济活动主要为处理肉类以及植物,对石核剥片和二次加工的空间概念分析,小长梁古人类在打片过程中仅采用前运算智力和初级的具体运算智力,考虑到石料质地,数量和适应等因素,石工业并不反映古人群体的全部智慧,而表现了一种权宜性行为方式,但是他们的认知水平不会超过12岁儿童的智力。