96 resultados para primate cognition


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精子的超低温冷冻保存为珍稀、濒危动物种质资源的保存、人类不育症的治疗、家畜繁殖以及辅助生殖技术(如人工授精、体外受精和胚胎移植)的进一步发展奠定了基础。灵长类动物精子的冷冻保存距今已有30多年的历史,到目前为止,全世界两百余种灵长类动物中仅有约15个物种的精子被冷冻保存的报道,而用冷冻精液人工授精产下后代的报道仅见于大猩猩、黑猩猩、食蟹猴、械猴和称猴等5种灵长类动物。冻精人工授精率如此之低主要是因为人们对灵长类动物精子的低温生物学知识、精子的冷冻损伤机制以及某些物质的冷冻保护作用机理缺乏了解,导致了冷冻复苏精子的存活率降低,受精力急剧下降。为了探讨灵长类动物精子冷冻损伤的机理,提高精子的冷冻保存效率,本论文以食蟹猴和称猴为动物模型,以冷冻复苏精子的运动度、质膜完整率和顶体完整率为检测指标,对.影响灵长类动物精子冷冻保存效果的因素作了积极的探讨和研究:1)研究了脯氨酸、谷氨酞胺和甘氨酸对食蟹猴精子冷冻保存的影响,发现一定浓度的氨基酸有利于食蟹猴精子的冷冻保存,但高浓度的氨基酸却会对冷冻复苏精子产生负面影响;2)首次建立了灵长类动物精子成分确定防冻液的冷冻保存方法,为准确分析研究精子冷冻损伤机制和某些物质的冷冻保护机理莫定了基础;3)对比研究了不同类型冷冻保存稀释液及不同渗透性防冻剂在食蟹猴精子冷冻保存中的作用以及对冷冻复苏精子功能的影响,筛选、优化出了凡种适合于食蟹猴精子冷冻保存的稀释液和渗透性防冻剂;4)比较研究了几种不同类型防冻液对食蟹猴和称猴精子冷冻保存的效果,发现适合食蟹猴精子冻存的防冻液也同样适合于称猴精子。本研究的结果既有利于改进现有的灵长类动物精子冷冻保存方法,又有利于对精子的冷冻损伤机制和保护性物质的作用机理作进一步的研究,为低温生物学和生物多样性的保护作贡献。

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A new theoretical model of Pattern Recognition principles was proposed, which is based on "matter cognition" instead of "matter classification" in traditional statistical Pattern Recognition. This new model is closer to the function of human being, rather than traditional statistical Pattern Recognition using "optimal separating" as its main principle. So the new model of Pattern Recognition is called the Biomimetic Pattern Recognition (BPR)(1). Its mathematical basis is placed on topological analysis of the sample set in the high dimensional feature space. Therefore, it is also called the Topological Pattern Recognition (TPR). The fundamental idea of this model is based on the fact of the continuity in the feature space of any one of the certain kinds of samples. We experimented with the Biomimetic Pattern Recognition (BPR) by using artificial neural networks, which act through covering the high dimensional geometrical distribution of the sample set in the feature space. Onmidirectionally cognitive tests were done on various kinds of animal and vehicle models of rather similar shapes. For the total 8800 tests, the correct recognition rate is 99.87%. The rejection rate is 0.13% and on the condition of zero error rates, the correct rate of BPR was much better than that of RBF-SVM.

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A new model of pattern recognition principles-Biomimetic Pattern Recognition, which is based on "matter cognition" instead of "matter classification", has been proposed. As a important means realizing Biomimetic Pattern Recognition, the mathematical model and analyzing method of ANN get breakthrough: a novel all-purpose mathematical model has been advanced, which can simulate all kinds of neuron architecture, including RBF and BP models. As the same time this model has been realized using hardware; the high-dimension space geometry method, a new means to analyzing ANN, has been researched.

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BACKGROUND: Hypoxia and ischemia induce neuronal damage, decreased neuronal numbers and synaptophysin levels, and deficits in learning and memory functions. Previous studies have shown that lycium barbarum polysaccharide, the most effective component of barbary wolfberry fruit, has protective effects on neural cells in hypoxia-ischemia. OBJECTIVE: To investigate the effects of Naotan Pill on glutamate-treated neural cells and on cognitive function in juvenile rats following hypoxia-ischemia. DESIGN, TIME AND SETTING: The randomized, controlled, in vivo study was performed at the Cell Laboratory of Lanzhou University, Lanzhou Institute of Modern Physics of Chinese Academy of Sciences, and Department of Traditional Chinese Medicine of Gansu Provincial Rehabilitation Center Hospital, China from December 2005 to August 2006. The cellular neurobiology, in vitro experiment was conducted at the Institute of Human Anatomy, Histology, Embryology and Neuroscience, School of Basic Medical Sciences, Lanzhou University, and Department of Traditional Chinese Medicine of Gansu Provincial Rehabilitation Center Hospital, China from March 2007 to January 2008. MATERIALS: Naotan Pill, composed of barbary wolfberry fruit, danshen root, grassleaf sweetflag rhizome, and glossy privet fruit, was prepared by Gansu Provincial Rehabilitation Center, China. Rabbit anti-synaptophysin, choline acetyl transferase polyclonal antibody, streptavidin-biotin complex kit and diaminobenzidine kit (Boster, Wuhan, China), as well as glutamate (Hualian, Shanghai, China) were used in this study. METHODS: Cortical neural cells were isolated from neonatal Wistar rats. Neural cell damage models were induced using glutamate, and administered Naotan Pill prior to and following damage. A total of 54 juvenile Wistar rats were equally and randomly assigned into model, Naotan Pill, and sham operation groups. The left common carotid artery was ligated, and then rat models of hypoxic-ischemic injury were assigned to the model and Naotan Pill groups. At 2 days following model induction, rats in the Naotan Pill group were administered Naotan Pill suspension for 21 days. In the model and sham operation groups, rats received an equal volume of saline. MAIN OUTCOME MEASURES: Neural cell morphology was observed using an inverted phase contrast microscope. Survival rate of neural cells was measured by MTT assay. Synaptophysin and choline acetyl transferase expression was observed in the hippocampal CA1 region of juvenile rats using immunohistochemistry. Cognitive function was tested by the Morris water maze. RESULTS: Pathological changes were detected in glutamate-treated neural cells. Neural cell morphology remained normal after Naotan Pill intervention. Absorbance and survival rate of neural cells were significantly greater following Naotan Pill intervention, compared to glutamate-treated neural cells (P < 0.05). Synaptophysin and choline acetyl transferase expression was lowest in the hippocampal CA1 region in the model group and highest in the sham operation group. Significant differences among groups were observed (P < 0.05). Escape latency and swimming distance were significantly longer in the model group compared to the Naotan Pill group (P < 0.05). CONCLUSION: Naotan Pill exhibited protective and repair effects on glutamate-treated neural cells. Naotan Pill upregulated synaptophysin and choline acetyl transferase expression in the hippocampus and improved cognitive function in rats following hypoxia-ischemia.

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药物滥用是一种慢性、复发性脑疾病,有着极其复杂的机理。其核心特征是强制性觅药和用药行为,即成瘾者失去了对药物寻求和使用行为的控制。大量的实验证据表明,药物滥用会导致认知功能的损伤和认知偏差,并会造成情绪的异常,这可能是药物滥用和复吸的原因。 本论文的目的在于进一步研究药物滥用对认知和情绪的影响及其相关的脑机制,为此我们首先利用一系列神经心理学的测试,包括简单反应时、选择反应时、快速序列视觉呈现和左右分辨测试,研究了阿片类物质滥用对认知功能(如信息处理能力、注意的时间特性、左右分辨能力等)和情绪反应的影响,并探讨了性别、戒断时间、成瘾历史和开始成瘾的年龄的相关作用。研究结果发现:1)海洛因依赖的病人在上述测试中均表现出明显的功能损伤。2)海洛因依赖的病人对成瘾相关的刺激存在认知偏差,如,在快速序列视觉呈现测试中,他们只在中性词语和负性词语上表现出扩大了的注意瞬脱,但是在成瘾相关词语上的表现与正常被试没有显著差异。3)海洛因依赖病人的情绪反应发生了改变:他们对负性词语的唤起度评分低于中性词语和成瘾相关词语,并小于正常被试对负性词语的唤起度评分;另一方面在快速序列视觉呈现测试中,情绪刺激对海洛因依赖病人的注意瞬脱的影响程度小于正常被试的情况。4)在海洛因依赖病人中发现的认知功能的损伤和认知偏差存在性别差异,女性病人认知功能的损伤程度较男性病人更为严重,并且认知偏差也较男性病人更为明显。5)对于不同的测试,戒断时间、成瘾历史和开始成瘾的年龄有不同的影响。本部分研究较为系统的揭示了药物滥用对于认知和情绪的影响及其特点。 为了进一步研究阿片类物质滥用对认知功能和情绪反应的影响机制,我们利用脑电和功能核磁共振成像,分别研究了吗啡成瘾过程中前额叶的两个主要部分(腹侧前额叶和背外侧前额叶)的变化情况以及海洛因依赖病人的杏仁核对成瘾无关的情绪刺激的反应。结果发现吗啡对腹侧前额叶和背外侧前额叶的脑电活动都造成了一定的影响,并且对脑电γ段的影响在给药后12小时仍然存在,这可能是药物滥用造成认知功能损伤的原因。另外,海洛因依赖病人的左侧杏仁核对情绪刺激的反应小于正常被试,尤其是对正性刺激的反应。这解释了药物滥用者存在情绪异常问题的原因。本部分研究在一定程度上解释了药物滥用对认知和情绪的影响机制,并为前额叶和杏仁核在药物滥用中所起的作用提供了进一步的证据。

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Inspired by human visual cognition mechanism, this paper first presents a scene classification method based on an improved standard model feature. Compared with state-of-the-art efforts in scene classification, the newly proposed method is more robust, more selective, and of lower complexity. These advantages are demonstrated by two sets of experiments on both our own database and standard public ones. Furthermore, occlusion and disorder problems in scene classification in video surveillance are also first studied in this paper.

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Watermarking aims to hide particular information into some carrier but does not change the visual cognition of the carrier itself. Local features are good candidates to address the watermark synchronization error caused by geometric distortions and have attracted great attention for content-based image watermarking. This paper presents a novel feature point-based image watermarking scheme against geometric distortions. Scale invariant feature transform (SIFT) is first adopted to extract feature points and to generate a disk for each feature point that is invariant to translation and scaling. For each disk, orientation alignment is then performed to achieve rotation invariance. Finally, watermark is embedded in middle-frequency discrete Fourier transform (DFT) coefficients of each disk to improve the robustness against common image processing operations. Extensive experimental results and comparisons with some representative image watermarking methods confirm the excellent performance of the proposed method in robustness against various geometric distortions as well as common image processing operations.

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本文以具有典型特征的苏北淤泥质潮滩海岸作为研究区,利用1975-2003年间14景覆盖该地区的Landsat和SPOT卫星影像作为主要数据源,结合地面调查和验证工作,在遥感影像处理和地理信息系统分析技术的支持下,对区内潮滩、岸线、水边线和盐沼植被等进行遥感解译,分析苏北辐射沙脊群和沿岸地貌的空间分布特征和动态演变趋势。研究结果表明:苏北辐射沙脊群海域的潮汐水位过程的不同步现象普遍存在,限制了常规遥感数据在苏北潮滩地貌研究中的适用范围和解译精度;在人工判别的辅助下,多光谱遥感的非监督分类方法可以有效解译淤泥质潮滩的水边线;利用修改型土壤调整植被指数(MSAVI)可以较好地提取潮滩上的盐沼植被信息;苏北沿岸潮滩的快速淤长促进了盐沼植被带向海侧快速扩展,近年来持续的潮滩围垦工程则不断从陆侧侵占盐沼植被带,使盐沼植被带宽度减小乃至消失;在大规模人类活动和自然条件的共同影响下,苏北辐射沙脊群海岸的岸线发育趋于平直化,无序的潮滩围垦项目使得可垦滩地资源被过度消耗;1975~2002年间,研究区北部和南部沿岸的高潮滩整体上处于淤长状态,中部沿岸潮滩和离岸沙洲高潮滩则被大面积侵蚀;1999年以来,研究区内低潮滩部位开始形成有序排列的滩面地物,并表现出逐年大面积蔓延的趋势,可能是滩涂紫菜养殖区扩展的结果。

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根据心理物理学、神经生理学、认知神经学等学科在视觉认知领域的部分研究成果,结合机器视觉、图像处理领域在图像增强方面已经提出的一些方法,提出了结合先验知识的多窗口结构下的分块中值滤波方法,在每一个窗口内单独进行处理与分析,突出了视觉处理目的,减少了运算量, 节省数据存储空间,达到了令人满意的滤波效果,能够在原始图像比较复杂的情况下,较好地对其进行预处理,可以改善、提高后期图像处理过程,如图像分割、图像分析的正确性和有效性。

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:本文从信息时代对人们认识上的影响,讨论了信息时代对生产、对统一的世界市场、对社会的影响。列举了世界经济进入新的繁荣期的特征。讨论了世界生产的形成和发展,市场竞争的三准则,市场竞争的各个历史阶段及全球化敏捷制造体系迅速发展的原因。分析了二十一世纪制造业面临的形势。详细地讨论了我国国有大中型企业的主要问题:1.产品问题;2.企业结构不合理;3.管理问题;4.质量问题;5.工艺手段和装备落后;6.历史包袱沉重等。提出了利用世界全球化生产体系发展的大好形势的三条对策:1.利用敏捷制造原理对企业进行重组;2.加速产品设计队伍的重建,增强新产品的设计能力;3.利用现代化手段实现现代化管理。

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本文初步探讨了遥控机器人监控的基本概念,得出这样一种认识:监控方式是机器人向智能化发展的一个恰当模式,监控系统是由人的高级智能与机器人的低级智能构成的系统.监控是系统中这两种智能相互作用的过程,人的智能应当能够在机器智能的不同级别上输入,我们研制了一个遥控机器人监控操作器的实验系统,通过实例和实验作了说明.

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Groundwater basin is important for water supply in northern China. The paper took the Jingsheng Basin in Lingshi County, Shanxi Province as a case to study the basin groundwater system by numerical modeling. The hydrogeological characteristics were analysed basing on the field investigation, and a three-dimensional groundwater flow model was established to describe the groundwater flow system in the Jingsheng groundwater basin. The boundary of the model was determined by using geophysics and GIS data, and the lumped parameter model of runoff was used to depict the transform between the surface water and groundwater, and the groundwater dating data was used to calibrate the model. All these methods were used to improve the model. The Software Visual MODFLOW 2000 was applied to set up the numerical groundwater flow model. The groundwater flow pattern in the average year, the high-water year and the low-water year were simulated respectively by the model. Some new cognition to the groundwater movement in Jingsheng Basin was obtained in the paper. The difficult problems were resolved when using the conventional and theoretical analysis to forecast and appraise the exploitation of the groundwater, and supplies the instructional technology base for the reasonable exploitation and optimization collocation. The numerical model will improve evaluation of the basin groundwater resources.

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Luo Ning ( Mineralogy, Petrology, Deposit Mineralogy) Directed by Fu Liyun With the increase of the level of exploration and development, North China field, as one of the maturing fields in the east, has gradually turned their prospecting targets to frontiers such as deep zones, lithologic hydrocarbon reservoirs, low permeable layers, special lithostromes, etc, which propose new challenges to mating technique of exploration engineering. In it, the special lithostrome of clay carbonate in Shu-Lu cave in Middle Flank exploration area locates in Es_3 generating rock. The area distribution is large, formation thickness is over 100 meters, the oil accumulation condition is excellent, prognostic reserves is over 80,000,000 tons, but how to effectively stimulate the special low permeable and fractured reservoir has become the bottle neck problem of stimulation and stable yields. In this thesis, through comprehensive evaluation and analysis of lithology, lithomechanics, hydrocarbon reservoir characteristics, the characteristics of fluid flow through porous medium and the stimulation measures in the past, we acquire new cognition of clay carbonate reservoirs, in addition, the research and application of first hydraulic fracturing has gained positive effect and formed commensurable comprehensive reservoir evaluation technique and mating engineering technique of hydraulic fracturing. The main cognitions and achievements are as follows: 1.Study of geological information such as lithololy analysis and nuclear magnetic logging, etc, indicates that clay carbonate formation of Shu-Lu cave is anisotropic, low permeable with high shale content, whose accumulation space gives priority to microcracks. 2.The analysis of lithomechanics of clay carbonate indicates that the hardness is moderate, Young’s modulus is between that of sandstone and limestone, clay carbonate presents plastic property and its breakdown pressure is high because of the deep buried depth. 3.The analysis of the drillstem test curves indicates that the flow and build-up pressure curve of clay carbonate of Shu-Lu cave mainly has three types: formation contamination block-up type, low permeable type, formation energy accumulation slowness type; the reservoir characteristics presents double porosity media, radial compounding, uniform flow vertical fracture, isotropy, moniliform reservoir type. The target well Jingu 3 belongs to moniliform reservoir type. 4.Through recognition and re-evaluation of the treatment effect and technologic limitations of acidizing, acid fracturing and gelled acidizing in the past, based on the sufficient survey and study of hydraulic fracturing home and abroad, combined with comprehensive formation study of target well, we launched the study of the optimization of hydraulic fracturing technique, forming the principal clue and commensurable mating technology aimed at clay carbonate formation, whose targets are preventing leak off, preventing sand bridge, preventing embedment, controlling fracture height, forming long fracture. 5. Recognition of stimulation effect evaluation.

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Oil and gas exploration of marine strata in China's Pre-Cenozoic residual basins is regarded as a worldwide puzzle because of existent problems and cruxes. Objectively speaking, the subsurface geologic structure is complicated, and the surface conditions of some areas are tough. On the other hand, there are still many problems to be solved in oil and gas exploration technologies of Pre-Cenozoic marine fades, and theoretic cognition about petroleum geology is not profound yet. Therefore, it is principal to explore integrated geophysical research ways of Pre-Cenozoic residual basins. Seismic prospecting and geophysical integrated interpretation technologies aimed at middle Paleozoic marine facies with deeper burial and complicated geologic conditions have not formed due to bad quality of deep strata data. Pre-Cenozoic strata, and especially extension, thickness and internal structure of Paleozoic strata can not be recognized from seismic profiles, so it is hard to systematically cognize structural features and oil-gas resources prospect of Pre-Cenozoic basins. To further investigation of fabric and structural features, basin prototype, formation and evolution pattern of Pre-Cenozoic basins, and also their control over formation, migration and aggregation of oil and gas, will play a guiding and promotive role in developing new surveying areas, selecting advantageous zones and predicting oil-gas resources.This paper follows the modem macrocontrol theory of "Region constrains local, deep strata controls shallow ones", and uses the integrated geophysical method of "One guide, two hinges, three combinations and multi feedbacks'*. Based on several years of geological and geophysical results of the Shengli Oilfield, and 14 newly-joint regional seismic profiles, deep structure and oil-gas bearing capacity of the Jiyang area are discussed and new cognitions are drawn as below.Seismic identification marks Tr, Tg, Tgl and Tg2 are established for importantPre-Cenozoic geological interfaces, and promoted to the whole Jiyang area.Through area-wide tracking and clogging of important seismic reflection marker,the isochronic framework of pre-Tertiary basin is set up in the Jiyang area for the firsttime, which is vital for basin research.Integrated with geological and geophysical research results, the Jiyang area isdivided into four first-order tectonic sequences- basement, lower tectonic layer,upper tectonic layer, and top tectonic layer. The basement and lower tectonic sequence which are related to Pre-Cenozoic are studied with emphasis.Through the research of regional seismic profiles, the point of view is given thatthe Kongdian Formation of Jiyang is structural transition period. The top-bottomunconformable interface of the Kongdian Formation is found out for the first time,and the basin model is determined primarily, which lay a basis for prototype basinresearch of the Jiyang Kongdian Formation.The distribution status of Middle-Paleozoic is delineated in the Jiyang area.The maximum thickness of Paleozoic lies in the top of the south declivity of half-graben. The thickness gets thinner towards the center of Mesozoic and Cenozoic half-graben basin, and even disappears. Structural action in the west-north affects the distribution of Paleozoic residual strata.6. The features of second-order tectonic sequence of the Jiyang depression isstudied and its evolution history of is rebuilt.Combined with the 5-stage evolution history of the China continent and structure evolution features of the Jiyang area, the structure sedimentary process since Paleozoic is divided into 5 periods - basement forming , Indosinian orogenic, Yanshan negative reversal, Himalayan extension and Neogene subsidence period.Combined with the research results of gravity, magnetic surveying and regionalprofiles, this paper brings forward the idea for the first time that the western boundaryof the Jiyang depression is the Ningjin-Yangpan fracture zone, and forms aside-column assemblage with the Wudi fracture zone.The opinion that under Middle-Cenozoic basins in the middle Jiyang area theremight superimpose an old residual basin is given for the first time. And if it is provedto be true, a new exploration space will be pioneered for Jiyang and even north China.There exists many types of tectonic-stratigraphic traps formed under piezotropy,extension and compound action in Pre-Cenozoic Jiyang. Therein all kinds of burialhills are the most important oil-gas trap type of Pre-Cenozoic, which should besurveyed layeredly according to the layout of oil sources.As such a new challenging project and field, the paper systematically analyses different geophysical responses of the Jiyang area, frames the deep structure of the area, and preliminarily recognizes the Pre-Cenozoic residual basins. It breaks through to a certain extent in both theory and practice, and is expected to provide new geophysical and geotectonic clues for deep exploration in Shengli.