图像增强的自适应免疫算法

介绍了自适应免疫算法的基本原理及实现步骤，并将其应用到图像的增强处理中，在传统的图像管理处理中，针对图像灰度分布的不同情况，需要定义相应的灰度变换函数。Tubbs将图像增强处理中几种常用的非线性变换函数表示成一个归一化的非完全Beta函数，但确定Beta函数参数仍是一个复杂的问题，本文利用自适应免疫算法来确定该变换函数的最佳参数值，通过对自然图像的仿真实验可以看出本文方法的有效性。     

东亚钳蝎食性的研究

东亚钳蝎(Buthus martensii Karsch)肉食性,尤其嗜食活体小动物。人工养蝎通常以黄扮虫、地鳖为饲料。若以黄粉虫为饲料,分点碟放的投食方式明显优于撒放的投食方式。在蝎的活动期内,昼夜取食活动高峰视季节不同出现在19～21时或20～23时。但幼蝎也常见白天取食。季节旺盛取食期是5～10月,15℃时不取食,20℃少量取食,25～30℃大量取食,35℃取食量最大。蝎的耐饥力较强,但供食不足易引发自相残食。     

Human slow wave sleep: A review and appraisal of recent findings,with implications for sleep functions,and psychiatric illness

Recent findings concerning human slow wave sleep (hSWS-stages 3+4; delta EEG activity) are critically reviewed. Areas covered include the significance of the first hSWS cycle; hSWS in extended sleep; relationship between hSWS, prior wakefulness and sleep loss; hSWS influence on sleep length; problems with hSWS deprivation; influence of the circadian rhythm; individual differences in hSWS, especially, age, gender and constitutional variables such as physical fitness and body composition. Transient increases in hSWS can be produced by increasing both the quality and quantity of prior wakefulness, with an underlying mechanism perhaps relating to the waking level of brain metabolism. Whilst there may also be thermoregulatory influences on hSWS, hypotheses that energy conservation and brain cooling are major roles for hSWS are debatable. hSWS seems to offer some form of cerebral recovery, with the prefrontal cortex being particularly implicated. The hSWS characteristics of certain forms of major psychiatric disorders may well endorse this prefrontal link.     

大熊猫尿中皮质醇含量变化的日周期

首次报道了4只大熊猫(.2;■.2)尿中皮质醇含量变化的24小时模式.连续两昼夜在动物排尿时收集尿样,尿中皮质醇含量用放射免疫法测定.4只大熊猫尿中的皮质醇含量变化均有明显的昼夜周期,在早晨2—6时持续上升,在6—7时达最高点,随即逐渐下降,雄性与雌性大熊猫分别在21时到21时半及20时到21时下降到最低点.雄、雌性大熊猫皮质醇的日周期相似,两者的皮质醇水平都是在3—7时显著高于日平均水平,中午12时至深夜1时,一般均低于日平均水平,24小时中皮质醇峰的最高值,雄性大熊猫高于雌性.     

Immunotherapy against antigenic tumors: a game with a lot of players

Our understanding of how immune responses are generated and regulated drives the design of possible immunotherapies for cancer patients. For that reason, we first describe briefly the actual immunological theories and their common perspectives about cancer vaccine development. Second, we describe cancer vaccines that are able to induce tumor-specific immune responses in cancer patients. However, these responses are not always followed by tumor rejection. At the end of the review, we discuss two possible reasons that might explain this dichotomy of cancer immunology. First, the immune response generated, although detectable, may not be quantitatively sufficient to reject the tumor. Second, the tumor microenvironment may modulate tumor cell susceptibility to the systemic immune response induced by the immunization. Finally, we discuss what, in our opinion, might be the best way to improve cancer vaccine strategies and how the relationship between the tumor and its surroundings might be studied in more details. Received 21 June 2001; received after revision 15 August 2001; accepted 15 August 2001     

X13—1菌体蛋白对小鼠免疫功能的影响

研究高蛋白含量的Fusarium菌株X13－1的最佳生长条件,并从菌丝体中获得了高达47％的菌体蛋白,再用热休克方法使其中RNA的含量降至2％以下,使之符合WHO标准,通过动物免疫实验证明,这种部分纯化的菌体蛋白可以增强小鼠的免疫功能。     

投影寻踪动态聚类模型

投影寻踪聚类模型在多因素聚类分析中被广泛应用并取得了满意的效果,然而,该模型还存在诸如密度窗宽参数取值经验确定等不足,有待改进提高.本文针对投影寻踪聚类模型的不足,首次把投影寻踪的思想和动态聚类方法结合起来构造投影指标,基于免疫进化算法,建立了投影寻踪动态聚类新模型.新模型一方面在整个运算过程中毋需人为给定参数,聚类结果客观、明确,另一方面,它还具有稳定性好、操作简便等特点.洪水分类的实际应用表明,投影寻踪动态聚类模型切实可行,取得了很好的效果,在多因素聚类分析领域具有广阔的应用前景.     

一类时滞免疫反应系统动力学行为仿真

研究一类时滞免疫反应系统在机体清除靶细胞能力对浆细胞增长有影响的情形下的动力学行为,用时滞微分理论证明系统正平衡点的稳定性与时滞的关系,给出其稳定判定方法。在模型解基础上,用仿真方法研究部分参数变化对系统动力学行为的影响,给出了免疫系统呈现不同动力学行为的参数范围,实现免疫系统动态特性的仿真。结果表明,对于给定时滞,免疫反应系统的动力学行为不敏感地依赖于抗体清除抗原速率,而敏感地依赖于抗原繁殖系数。     

免疫响应反馈理论在水轮机调节系统中的应用

免疫响应反馈理论是维持生物体免疫平衡的关键,T细胞在不同的免疫阶段所具有的促进和抑制功能,保证了系统的快速响应和足够的稳定性。针对水轮机调节系统具有高度非线性、时变不确定、非最小相位等特点,通过免疫系统与控制系统的类比,借鉴免疫响应调节机理,利用免疫PID控制器来控制水轮机调节系统,并对该系统进行了仿真研究,仿真结果表明当工况变化和存在扰动时免疫PID控制器能有效的改善水轮机调节系统的动态性能,增强其鲁棒性和抗强干扰的能力。