45 resultados para ADALET VE KALKINMA PARTISI (AKP)


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The Zhikong Scallop, Chlamys farreri, is one of the most Important bivalve mollusks cultured in northern China However, mass mortality of the cultured C farreri has posed a serious threat to the maricultural Industry in recent years. Acute Viral Necrobiotic Virus (AVNV) is believed as an important etiological agent causing the scallop mass mortalities To understand the mechanism behind the AVNV associated scallop disease and mortality, we assessed the physiological and immune responses of C farreri to the virus infection using oxygen consumption rate, ammonium-nitrogen excretion rate, hemocyte copper, zinc superoxide dismutase gene expression, and plasma superoxide dismutase activity and alkaline phosphatase activity as indicators Scallops challenged by AVNV at 25 C developed typical disease signs 2 days after virus injection Before the disease manifested, scallop oxygen consumption and NH4+-N excretion rates rose and then fell back. Real-time PCR revealed that the hemocyte cytosol Cu, Zn SOD gene expression was upregulated followed by recovery The plasma SOD activity, however, augmented consistently following virus injection Moreover, plasma AKP activity first lowered and then elevated gradually to the highest level at 24 h post virus injection Scallops challenged by AVNV at 17 degrees C neither developed notable disease nor showed obvious responses that could be associated with the virus infection. While the results suggested a correlation between the elevated seawater temperature and the AVNV infection associated C farreri mortalities, they also indicated that the viral infection provoked multiple physiological and immune responses in the host scallops (C) 2010 Elsevier Ltd All rights reserved

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栉孔扇贝(Chlamys farreri)是我国北方重要养殖扇贝种类,在海湾扇贝和虾夷扇贝引进以前,其年产量占我国扇贝总产量的80%。但自1997 年以来,我国北方大部分养殖区连续发生养殖栉孔扇贝大批死亡事件,严重影响和损害了栉孔扇贝养殖业的发展。我国栉孔扇贝大规模死亡是多种因素综合作用的结果。大致可分为生物因素与非生物因素:非生物的因素有夏季水温过高、养殖密度过高、养殖环境退化等。生物因素有流行性病原生物的侵害和扇贝种质的退化等。其中,急性病毒性坏死症(Acute Viral Necrobiotic Disease, AVND)病毒造成栉孔扇贝大规模死亡现象的研究已经开展。本研究通过生理学、免疫学技术和手段研究栉孔扇贝对急性病毒性坏死症病毒的生理和免疫应答,以期更好的了解栉孔扇贝对这一病毒的防御机制,为扇贝病害防治提供资料。 本研究对不同温度下栉孔扇贝感染AVND 病毒后的耗氧率和排氨率进行了测定。结果显示,在17℃下,病毒组和注射生理盐水组栉孔扇贝的耗氧率逐渐升高,但两者无显著差异;方差分析显示,各组间排氨率的变化无显著差异。在25℃下,栉孔扇贝闭壳肌注射AVND 病毒和注射生理盐水组栉孔扇贝的耗氧率逐渐升高,在12 小时取得最大值,对照组则变化不大。方差分析显示,注射病毒组与注射生理盐水组和对照组之间有显著差异(P<0.05)。同时,对栉孔扇贝感染AVND 病毒的致病剂量进行了研究,在25℃水温下,栉孔扇贝肌肉注射感染AVND 病毒后,只有150 μl 组表现出明显患病症状并在第三天开始出现死亡现象,注射50、100 μl 组则无明显症状;17℃下栉孔扇贝感染AVND 病毒后无明显患病症状,表明AVND 病毒对栉孔扇贝的感染致病具有剂量和温度依赖性。 对于25℃水温下栉孔扇贝感染AVND 病毒后血清中相关免疫酶类活力变化进行了测定。栉孔扇贝感染AVND 病毒后血清中SOD 的活性逐渐升高,在48小时达到最大值,方差分析显示不同时间点之间的SOD 活性有显著差异(P<0.05),在48 小时,病毒组和生理盐水组间的SOD 活性有显著差异(P<0.05),在其它时间点无显著差异。酸性磷酸酶(ACP)的活力在感染病毒2 小时后升高,在12 小时下降,然后又升高,在48 小时达到最大值。方差分析显示不同时间点之间的ACP 活性有显著差异(P<0.05),在2 小时和48 小时,病毒组和生理盐水组间的ACP 活性有显著差异(P<0.05)。碱性磷酸酶(AKP)的活力变化趋势与ACP 相同,在24 小时达到最大值。方差分析显示不同时间点之间的AKP 活性有显著差异(P<0.05)。在2 小时、12 小时、24 小时病毒组和生理盐水组间有显著差异(P<0.05)。栉孔扇贝酚氧化酶的活性最大值在48 小时,但与生理盐水对照组之间无显著差异。溶菌酶(Lysozyme)活性在病毒组和生理盐水对照组间无显著差异,病毒组最大值在2 小时取得,对照组在24 小时取得。结果表明栉孔扇贝通过升高或调节自身免疫相关蛋白酶类合成应对AVND 病毒侵染。 采用荧光实时定量PCR 技术,对栉孔扇贝感染AVND 病毒后免疫相关基因的时空表达规律进行了研究。水温17℃下,栉孔扇贝肌肉注射感染AVND 病毒后超氧化物歧化酶(SOD)基因mRNA 的表达量逐渐上升,在注射后24 小时达到最大值,约为空白对照组的1.8 倍,方差分析显示,病毒组SOD 的表达量不同时间点之间有显著变化(P<0.05);但与生理盐水对照组相比较,病毒组SOD表达量无显著差异。在水温25℃下SOD 基因mRNA 的表达量逐渐上升,在注射后6 小时达到最大值,约为对照组的1.5 倍,空白对照组的2.2 倍。病毒组SOD的表达量不同时间点之间有显著差异(P<0.05);在感染后2、6、12、24 小时病毒组SOD 表达量比对照组有显著升高(P<0.05)。溶菌酶基因在肝胰脏中的表达升高,在6 小时达到最大值,约为生理盐水对照组的1.5 倍,空白对照组的2.7倍,在48 小时取得最小值(低于空白对照组)。病毒感染后不同时间之间溶菌酶基因表达有显著差异(P<0.05),感染后6、24 和48 小时病毒组溶菌酶基因表达比对照组有显著升高(P<0.05)。在AVND 病毒感染后6 小时,在肝胰脏、性腺、肌肉、鳃中溶菌酶mRNA 量急剧增加,分别达到了空白对照组的4.7 倍、3.8 倍、13.43 倍和25.15 倍。方差分析显示在不同组织部位的表达有显著差异(P<0.05)。表明AVND 病毒感染后栉孔扇贝免疫相关基因的表达具有时序性和组织部位特异性。

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自1997年3月至1999年2月,从青岛麦岛海珍品养殖场购买栉孔扇贝,利用普通组织学、组织化学、透射电镜、扫描电镜、电镜细胞化学和生物化学等技术,对栉孔扇贝血细胞的形态、血淋巴中参与免疫防御的酶的活力和免疫刺激剂对血淋巴中酶活力的影响进行了研究。将其血细胞分为:拟淋巴细胞、血栓细胞、中性粒细胞、嗜碱性粒细胞、嗜酸性粒细胞和巨噬细胞6类。中性粒细胞对细菌的吞噬能力最强,嗜碱性粒细胞吞噬能力较弱,嗜酸性粒细胞无吞噬能力。无颗粒细胞中只有少量较大的细胞具有吞噬能力。扫描电镜观察栉孔扇贝血细胞有圆形、椭圆形和梭形3种形状。多数血细胞容易变形形成伪足。可形成大量长的纤维状伪足的血细胞具有凝血功能。血细胞溶酶体呈强的酸性磷酸酶(ACP)阳性。碱性磷酸酶(AKP)阳性颗粒常沿细胞膜分布。生化测定,血细胞和血清中均存在ACP和AKP活性。血清中ACP和AKP的最适pH值分别为4.4和10.3,最适温度分别为35 ℃和55 ℃。血细胞质中直径分别为300~430nm 和130~200nm的大、小两种颗粒呈强的酚氧化酶(PO)阳性;次级溶酶体和小颗粒呈旨的髓过氧物酶(MPO)阳性。生化测定,血清中存在PO和MPO活性,血细胞仅有MPO活性。血清中PO和MPO的最适pH值分别为6.0和6.5,最适温度分别为45 ℃和35 ℃。血细胞中超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活力分别为312.7U和124.4U,血清中SOD和CAT活力分别为102.3U和73.8U;血细胞中CuZn-SOD和Mn-SOD的活力分别为其SOD总活力的70.3%和29.7%,血清中仅存在CuZn-SOD活性。脂多糖、硒多糖和酵母聚糖A对栉孔扇贝血清和血细胞中溶菌酶、ACP、AKP、PO、MPO、SOD和CAT7种酶的活力均有激活加强作用。

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本文研究了海洋微藻在白斑综合症(white spot syndrome)暴发中的可能作用,以及阴离子表面活性剂十二烷基硫酸钠(SDS)和十二烷基苯磺酸钠(SDBS)长期暴露对紫贻贝(Mytilus galloprovincialis)生物标志物系统的影响(72 d)。 1.海洋微藻在养殖对虾白斑综合症传播中的作用研究 为了证实海洋微藻是否是养殖对虾白斑综合症的传播途径,我们首先将六种海洋微藻:球定边金藻(Isochrysis galbana)、中肋骨条藻(Skeletonema costatum)、小球藻(Chlorella sp. )、赤潮异湾藻(Heterosigma akashiwo)、锥状斯氏藻(Scrippsiella trochoidea)和盐藻(Dunaliella salina),与人工注射感染白斑病毒(white spot syndrome virus)的成体日本囊对虾共同培养,用套氏PCR方法检测共培养的微藻能否携带白斑病毒。在此基础上,进一步研究了共培养后的海洋微藻是否能感染幼体日本囊对虾。研究结果表明,除了H. akashiwo,实验海洋微藻均可携带白斑病毒,但它们携带病毒的能力有明显差异,Chlorella sp.和S. trochoidea携带白斑病毒的能力较强;但是,与白斑病毒的其他携带者(如桡足类等)不同,携带病毒的海洋微藻10天后病毒检测结果均呈阴性。共培养后小球藻组可感染幼体日本囊对虾,但幼体携带病毒的量只能通过二步PCR方法才能检测到。上述结果表明,海洋微藻在WSSV的水平传播途径中具有一定的作用。 2.表面活性剂对紫贻贝生物标志物系统的影响研究 以青岛胶州湾现场调查数据为依据,选择阴离子表面活性剂十二烷基硫酸钠(SDS)和十二烷基苯磺酸钠(SDBS)作为污染物、以近海底栖生物紫贻贝为受试生物,研究了长期暴露后紫贻贝生化指标(SOD, CAT, GSH, GPx, GST, iNOS, AKP)和遗传毒理指标(AFLP指纹图谱)的变化。实验结果发现: 经过72d不同浓度暴露后,SDBS实验组紫贻贝体内的SOD、CAT和iNOS活性均有显著下降(除CAT 0.1mg/L组外),GSH、GST和GPx在3.0mg /L SDS、SDBS组较各自对照组均有显著升高。SDBS对紫贻贝生化指标影响的显著性水平大于SDS。统计分析显示,SDBS暴露组下GST与GPx呈显著正相关关系,iNOS与SOD也表现出一定正相关,但GSH与CAT、GSH与SOD呈现显著负相关关系。SDS浓度与GST呈显著正相关,而SDBS浓度与CAT呈显著负相关。另外,实验结果发现后闭壳肌中iNOS是一个具有应用前景的阴离子表面活性剂暴露生物标志物。AFLP标记结果统计显示,在实验给定的污染物浓度下,SDBS基因毒性要大于SDS;不同的DNA指纹图谱以及遗传距离图显示不同的污染物造成的DNA损伤是不同的。结果表明,在长期暴露条件(72 d)下,一定浓度的阴离子表面活性剂可以对岗哨生物紫贻贝的SOD, CAT, GSH, GPx, GST, iNOS和AFLP指纹图谱一组指标产生显著影响。

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以奥利亚罗非鱼(Oreochromis aureus)为实验对象,设计了3种不同的摄食类型,分别是鲜活饵料组、饥饿3周后饱食投喂组和人工饲料组。鲜活饵料组投喂冰冻赤子爱胜蚓,利用蚯蚓体内丰富的营养成分和活性物质,以期获得奥利亚罗非鱼良好的生长状况;饥饿后饱食组是指饥饿3周后,以人工饲料饱食投喂2周,用于研究饥饿与补偿生长获得快速生长时血液理化指标的变化情况;人工饲料组作为对照组。纯淡水条件下养殖,水温25±2℃。测定了奥利亚罗非鱼在3种摄食类型饲喂下某些血液生理生化指标变化的情况,并将指标变化情况与增重率做相关性分析,试图找出能够反映奥利亚罗非鱼生长性能的血液生理生化指标。 研究结果表明,奥利亚罗非鱼在饥饿3周后获得了补偿生长,补偿生长时的增重率和特定生长率显著高于人工饲料组(P<0.05),高于鲜活饵料组,但差别不显著;相关性分析研究表明血清总蛋白、胆固醇、四碘甲状腺原氨酸(T4)与增重率极显著相关(P<0.01),血红蛋白显著相关(P<0.05),红细胞、白细胞、碱性磷酸酶高度相关(相关系数为0.580、0.551和0.557),因此,建议血清总蛋白、胆固醇和血红蛋白可作为能够反映罗非鱼生长性能的新指标。 根据序列设计引物,PCR反应条件:变性温度:95 ℃,3 min;退火温度:57℃,20 sec;延伸温度:72℃,5 min,共36个循环,从牙鲆、黑鲪和鲈鱼中克隆出胰岛素样生长因子(IGF-Ⅰ)部分序列,首次证实了IGF-Ⅰ在3种海水鱼中的存在。 利用蛋氨酸与ZnSO4•7H2O,在pH 5.5、80℃下,反应1小时,采用蛋氨酸与硫酸锌2:1的配料比,合成出了产物蛋氨酸螯合锌,蛋氨酸螯合锌外观白色,粉状,室温下微溶于水,不溶于乙醇,并用原子吸收光谱法测定其含锌量为15%,螯合率为88.2%。

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栉孔扇贝是我国重要的海水养殖品种,自1997年以来陆续爆发的大规模死亡,不仅造成了巨大的经济损失,而且直接威胁到现有产业的生存和发展。本研究通过比较扇贝在连续刺激条件下的不同免疫反应,推测栉孔扇贝中有无免疫致敏和记忆现象,观察短期免疫刺激对扇贝再次遇到相同病原物刺激时死亡率的影响,探讨栉孔扇贝的免疫致敏作用,并对其机制进行初步探讨,以期更好地了解扇贝的免疫防御机制,为扇贝病害防治提供参考。 利用荧光实时定量PCR技术检测了扇贝受到鳗弧菌连续等量刺激后两种重要病原识别受体(PRR)基因的表达。结果显示,在受到连续两次刺激后CfPGRP-S1、LGBP基因的表达量均有不同程度的增加。其中CfPGRP-S1基因在受到第二次刺激后表达量增加的幅度高于第一次,且基因表达显著性增加的时间比第一次提前;LGBP基因在第二次刺激后,表达量显著性增加的时间也比第一次提前。同时,对同批处理的扇贝进行重要免疫指标的检测分析发现两次刺激后吞噬率变化不显著,而第二次刺激后吞噬指数的最大峰值高于第一次,并且最大峰值出现的时间比第一次提前;血淋巴中的抗菌活力和肝胰腺中SOD、MDA含量在两次刺激前后的变化不显著。在脊椎动物中,识别能力和抗菌能力的提高是免疫记忆的两个重要特点,栉孔扇贝在第二次免疫刺激后PRR识别能力的提高和吞噬作用的增强,说明扇贝中可能存在类似脊椎动物免疫记忆的免疫致敏作用。对扇贝进行两次鳗弧菌浸泡刺激,第一次为短期浸泡刺激,第二次为长期浸泡刺激。结果发现,第一次浸泡过的扇贝在遭受相同病原第二次刺激时,在一定时间段内其死亡率比未受第一次刺激的扇贝极显著降低,表明第一次的短期病原刺激增强了扇贝对第二次刺激的抵抗能力。同时比较第二次刺激过程中扇贝免疫指标的变化发现经过短期刺激扇贝的吞噬作用、ACP和AKP活性比未受过刺激的扇贝显著增强,而其他指标包括POL、SOD则差异不显著,说明增强的吞噬作用、ACP和AKP活性与扇贝的死亡率下降有关。研究结果表明栉孔扇贝中存在免疫致敏(immune priming)现象,短期刺激可以提高扇贝的免疫反应能力,增强扇贝机体对相同病原物的抵抗能力。

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本文提出一种基于多传感器融合的组合导航方法,能够在小型旋翼无人机上实现低成本、高精度导航定位.该方法通过建立导航系统的机械编排模型,设计了一个17状态的扩展卡尔曼滤波器(EKF).对加速计的零偏和陀螺仪的漂移进行在线估计,实时的补偿传感器的测量误差.从而对旋翼无人机的速度、位置、角速度和姿态等参数进行精确的估计.通过对实际飞行数据仿真实验,并对比参考的导航系统,证明该方法在飞机的全包线飞行下均能够解算出可靠的导航信息。

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本文以跟踪电视系统中自适应量化器为设计背景,提出了一种新的、实时自适应的快速图象量化方法——逐极均值法,文中首先用Lloyd-Max最佳量化理论分析了这种量化方法的均方误差失真,讨沦了图象中存在孤立亮点时的处理方法。然后论述了这种量化方法应用于跟踪电视系统中的性能,即实现的简单、快速性;对照度变化的自适应性;及图象对比度增强效果。文中通过图象处理实验结果验证了这种量化方法的性能和理论分析的正确性。最后得出结论:逐极均值法量化器是一种能够代替LlodyMax最佳量化器的次佳量化器,这种量化器可以很好地满足跟踪电视系统中对自适应量化器的设计所提出的各方面性能要求;它对那些要求实现简单、实时自适应的量化器应用领域也将具有一定意义。

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九十年代以来,领导信息系Executive Information System,EIS) 日益用广泛,领导信息系的开已成业实CIMS 的一个重要目本文CIMS 境下EIS 用与研究作了一些探。文中先介EIS 的概念模型、开方法及制造EIS 发应:提出了建立数据仓库实现EIS 的数据;重点介了一个JS~CIMS 领导信息系实现

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Using the approximate high-frequency asymptotic methods to solve the scalar wave equation, we can get the eikonal equation and transport equation. Solving the eikonal equation by the method of characteristics provides a mathematical derivation of ray tracing equations. So, the ray tracing system is folly based on the approximate high-frequency asymptotic methods. If the eikonal is complex, more strictly, the eikonal is real value at the rays and complex outside rays, we can derive the Gaussian beam. This article mainly concentrates on the theory of Gaussian beam. To classical ray tracing theory, the Gaussina beam method (GBM) has many advantages. First, rays are no longer required to stop at the exact position of the receivers; thus time-consuming two-point ray tracing can be avoided. Second, the GBM yields stable results in regions of the wavefield where the standard ray theory fails (e.g., caustics, shadows zones and critical distance). Third, unlike seismograms computed by conventional ray tracing techniques, the GBM synthetic data are less influenced by minor details in the model representation. Here, I realize kinematical and dynamical system, and based on this, realize the GBM. Also, I give some mathematical examples. From these examples, we can find the importance and feasibility of the ray tracing system. Besides, I've studied about the reflection coefficient of inhomogeneous S-electromagnetic wave at the interface of conductive media. Basing on the difference of directions of phase shift constant and attenuation constant when the electromagnetic wave propagates in conductive medium, and using the boundary conditions of electromagnetic wave at the interface of conductive media, we derive the reflection coefficient of inhomogeneous S-electromagnetic wave, and draw the curves of it. The curves show that the quasi total reflection will occur when the electromagnetic wave incident from the medium with greater conductivity to the medium with smaller conductivity. There are two peak, values at the points of the critical angles of phase shift constant and attenuation constant, and the reflection coefficient is smaller than 1. This conclusion is different from that of total reflection light obviously.

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IQ Structure, Psycholinguistic and Visual-motor Abilities Study on Children Learning Disability TONG Fang Directed by professor Zhu Liqi (Developmental and educational psychology) ABSTRACT Objective To comprehensive analyze the IQ structures, and relationships among IQ, psychometric characteristics and visual-motor integration on children disability. At same time, to probe into the family factors that influenced IQ, psycholinguistic abilities and behavior of LD children. Method (1) Downloading the papers on children learning disability from www.cqvip.com and www.wanfangdata.com, in which, the articles were collected by key words from 1985 to 2005. To conduct meta-analysis on IQ construction, compare the case group and the control group, including full IQ, verbal and practice IQ. (2) Designed with model compared and self-compared, 59 diagnosed learning disability children, tested themes with WISC, ITPA and Berry’s VMI. WISC included 10 items, 5 of which subtotal to verbal and practice IQ respectively. IPTA included 10 items, too, 5 process of which subtotal to auditory and visual perception. The first 3 items shared representation level, the other 2 of that shared automatic level.VMI had one score. Analyzed factors and levels with description and Pearson Correlation. To probe to linguistic internal alternately functions of LD children, and compare the scores of groups in different IQ. (3) Analyzed the perspective questionnaire filled by parents. Early development facts compared with model groups. Factors relationships analyzed with Kendall correlation, KOM and Bartlett’s test of sphericity, Promax Rotation. Results: (1) There have been 319 papers related with LD, in which 36 with IQ and 14 valid reports have been analyzed by Meta. FIQ’s 95%CI (confidence interval) is 2.418 ~ 0.172, VIQ between the difficulty and non- difficulty group. C-WISC-R reports were 10 papers, of which, 95%CI of FIQ is 2.424 ~ 0.676, of VIQ is 2.314 ~ 1.196, of PIQ is 2.176 ~ 0.176. The VIQ comparing the PIQ, 95%CI is 1.1 ~ -0.07 in difficulty group and 0.5 ~ -0.0046 in non-difficult group. Nevertheless, in the other 4 tests, FIQ’s 95%CI is 2.00 ~ -0.818 between LD and NLD. (2) Children psycholinguistic abilities had strong relation with Berry’s VMI test excluding auditory reception, and with perceptive factor of intelligence excluding verbal expression. Auditory reception and visual closure had strong relation with FIQ and PIQ. Grammatic closure, visual association and manual expression had strong relation with concept factor. The representational and automatic levels are depended on integration of auditory and visual procession. Lower verbal expression (VE) let to lower expression process and low scores on representational level. Lower visual sequential memory (VSM) let to lower memory process and influenced automatic level. Groups compared by IQ 90 show that LD children with under IQ 90 had lower scores on items of IPTA than with up IQ 90 excluded verbal expression. It was proved that IQ administrated the linguistic ability. Nevertheless, general abilities deficiency didn’t show influencing on the types of the perceptive delay. There was mutual function among linguistic ability on LD children. Auditory and visual level are overlapped each other. Not only show higher Decoding and lower Encoding on Auditory perception, lower Decoding and higher Encoding on Visual perception, in representation, but also higher Sequential remember, lower Closure on Audition, and lower Sequential member, higher Closure on Vision, in Automation. Nevertheless, there was no different between Representational and Automatic level, which may be the relationship of parallel or evolution. (3) Major family factors were father’s education, occupation. Lower auditory perception related to unconcerned, lower visual perception related to premature delivery and written slowly. Threatened–abortion, childbirth-suffocated were known as influencing children’s IQ and later linguistic abilities. It wasn’t shown that dosage relationship with the types of perceptive delay. Conclusion: (1) The FIQ, VIQ and PIQ of Children with LD is lower than that of NLD group. There is no significantly different between VIQ and PIQ in LD and NLD groups. (2) The objectives of ITPA and WISC tests are differently. The psycholinguistic abilities had strong relation with perceptive factor and VMI. Some facts of IPTA related with FIQ. IQ had strong administration on linguistic abilities. There was mutual function among linguistic internal abilities. (3) Family facts on IQ and psycholinguistic abilities were Father’s education, abnormal pregnant and abortion. It would be pre-show development delay in early period.

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That relapse still exists even after prolonged withdrawal is a difficult issue in the medical cure of drug addiction. Neuro-adaptation induced by prolonged exposure to addictive drugs is the neural mechanisms of both compulsive drug seeking and relapse.Neuro-adaptation caused by addictive drugs increases the individuals’ response to drugs and on the other hand, it reduces the response to natural reward in withdrawn individuals.There must be common neural mechanisms between the co-existing phenomena, and there must also be unique neural mechanisms in the drugs.To reveal the neuro-adaptation arising in the process from random, controllable drug-use to uncontrollable compulsive drug seeking is of great significance both theoretically and practically.Based on the above hypothesis, in order to reveal the function of alpha adrenergic receptor in compulsive drug-seeking motivation during the process of drug addiction, using sensitization of morphine-induced psychomotor activity as behavioral model, through the method of behavioral pharmacology, the neural mechanisms of alpha adrenergic receptor’s involvement in the process of addiction has been studied.The adjustment function caused by alpha receptors in medial prefrontal cortex and nucleus accumbens to morphine-induced psychomotor activity has been compared in the period of first use of drugs and in repetitive-use period. Furthermore, the effect on novelty seeking caused by alpha-receptors in relevant brain areas has also been compared. Major results are as follow: 1 After prolonged morphine exposure, rats’ response to morphine-induced psychomotor activity is strengthened and response to novel object induced reward weakened. 2 Injection of prazosin in medial prefrontal cortex will block morphine-induced psychomotor activity of naïve rats, however, it will not block that of morphine-withdrawn rats, but it will block the novelty seeking behavior of morphine-withdrawn rats. 3 Injection of clonidine in medial prefrontal cortex will block morphine-induced psychomotor effect of both naïve rats and morphine-withdrawn rats, and will block the novelty seeking behavior of morphine-withdrawn rats. 4 Injection of prazosin in nucleus accumbens will not affect the morphine-induced psychomotor effect of either naïve rats or morphine-withdrawn rats, nor will it affect the novelty seeking behavior of morphine-withdrawn rats. 5 Injection of clonidine in nucleus accumbens will block morphine-induced psychomotor effect of naïve rats, however, it will not block that of morphine-withdrawn rats, nor will it affect the novelty seeking behavior of morphine-withdrawn rats. These results show: 1 The weakening of the function of alpha1 receptors in medial prefrontal cortex and alpha2 receptors in nucleus accumbens caused by repetitive exposure to morphine is probably the cause of compulsive drug-seeking activity. 2 Blocking alpha1 receptors in medial prefrontal cortex accelerates the loss of interest in natural reward after morphine withdrawal. 3 Blocking alpha2 receptors in medial prefrontal cortex not only restrains drug-seeking motivation, but also blocks the individual’s seeking motivation for novelty stimulus, which suggests that, while selecting medicine for curing addiction, it should be considered to reduce the influence on natural reward as much as possible and to avoid major side-effect.

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Research on naïve physics investigates children’s intuitive understanding of physical objects, phenomena and processes. Children, and also many adults, were found to have a misconception of inertia, called impetus theory. In order to investigate the development of this naïve concept and the mechanism underlying it, four age groups (5-year-olds, 2nd graders, 5th graders, and 8th graders) were included in this research. Modified experimental tasks were used to explore the effects of daily experience, perceptual cues and general information-processing ability on children’s understanding of inertia. The results of this research are: 1) Five- to thirteen-year-olds’ understanding of inertia problems which were constituted by two ogjects moving at the same spped undergoes an L-shaped developmental trend; Children’s performance became worse as they got older, and their performance in the experiment did not necessarily ascend with the improvement of their cognitive abilities. 2) The L-shaped developmental curve suggests that children in different ages used different strategies to solve inertia problems: Five- to eight-year-olds only used heuristic strategy, while eleven- to thirteen-year-olds solved problems by analyzing the details of inertia motion. 3) The different performance between familiar and unfamiliar problems showed that older children were not able to spontaneously transfer their knowledge and experience from daily action and observation of inertia to unfamiliar, abstract inertia problems. 4) Five- to eight-year-olds showed straight and fragmented pattern, while more eleven- to thirteen-year-olds showed standard impetus theory and revised impetus theory pattern, which showed that younger children were influenced by perceptual cues and their understanding of inertia was fragmented, while older children had coherent impetus theory. 5) When the perceptual cues were controlled, even 40 percent 5 years olds showed the information-processing ability to analyze the distance, speed and time of two objects traveling in two different directions at the same time, demonstrating that they have achieved a necessary level to theorize their naïve concept of inertia.

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Research on naïve biology investigates children spontaneous understanding of biology objects, phenomena and function. Previous researches focus mostly on biology phenomena. Little has done on organism’s function, such as eating food. Many research in this field found that children were unable to categorize food by nutrition criterion, but rely on physical cues. In order to investigate the development of children’s naïve understanding of food and to find if they can classify food by nutrition criterion, three age groups (5-year-olds, 7-year-olds, and 9-year-olds) were included in this study. Varies experimental tasks were also used to explore the children’s understanding of food and its function. The results showed as the followings: 1) A few 5-year- old children can classify food by nutrition criterion when they take the spontaneous classification task. However, more and more children can realize what make a kind of food different from another can be the nutrition it contains. 2) Kindergarteners can find the relation between food and its output. When they become older, more and more children can explain the relation by consistent theory. It can be said that 9-year-old children have already have a profound understanding of nutrition. They gradually developed naive theory of biology on nutrition level. 3) Even kindergarteners can understand the concept of “food balance”. However, with development there was a significant age increase in food balance choice. 4) Children’s knowledge of food balance grows with age, but urban and rural educational background influence cognitive performance.

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Research on children's naive concepts has previously tended to focus on the domains of physics and psychology, but more recently attention has turned to conceptual development in biology as a core domain of knowledge. Because of its familiarity, illness has been a popular topic for researchers in this domain. However, they have only studied the children’s understanding of its causes. Other aspects of illness, such as treatment and prognosis, have received little attention. This research addresses the development of 5- to 9-year-old children’s understanding of the causes of illness and their probabilities via open-ended and forced choice interviews. The results of this research are: 1) Most of the 5- to 7-year-old children used behavioral causes to explain illness, and the 9-year-old children primarily used biological causes to interpret illness. With age, more and more children selected psychological causes to explain illness. 2) Pre-school children did not over-generalize contagions to non-contagious illnesses. They used behavioral and biological causes to explain contagious illnesses. For non-contagious illnesses, they chose only behavioral causes. 3) Most of the children used only one kind of cause to explain illness. 4) Some preschool-aged children viewed outcomes of familiar causes of illness as probabilistic. With age, more and more could make uncertain predictions of illness. 5) The children’s understanding of the causes’ probabilities appeared to be based on naïve biology. 5- to 9-year-old children often made probabilistic predictions by analyzing a single cause of illness. 6) Children coming from higher educational backgrounds outperformed their counterparts coming from lower educational backgrounds with respect to understanding illness. 7) Specific knowledge acquired could generally improved the preschoolers’ understanding of causes of illness and their probabilities.