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Inter-simple sequence repeat (ISSR) analysis was used to assess eleven pairs of Undaria pinnatifida (Harv.) Suringar male and female gametophytes. After screening fifty primers, 18 ISSR primers were selected for final analysis. A total of 104 loci were obtained, of which 77 were polymorphic, among the gametophytes studied. Genetic relationships were analyzed with simple matching (S), Jaccard's (J) and Dice's (D) distance coefficients. Little genetic variations were found among the selected Undaria gametophytes, for instance, the genetic distances ranging from 0.010 to 0.125 with Dice coefficients. UPGMA dendrograms showed that 11 pairs of Undaria gametophytes were distributed into five groups. Most Undaria strains cultivated in China exhibited closely genetic relationships with the strains from Japan. However, gametophytes from Qingdao appeared as distinct clades from other Undaria strains with all three distance coefficients used. Mantel test showed that the three distance measurements generated congruent clustering patterns on the same data. Our results demonstrated the feasibility of applying ISSR markers for genetic analysis of Undaria gametophytes. (c) 2006 Elsevier B.V. All rights reserved.

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Catecholamines regulate several physiological processes in mollusks. Many pharmacological experiments have been conducted to determine the effects of adrenergic agonist and antagonist of catecholamine receptors on Meretrix meretrix metamorphosis. Results showed that adrenaline (AD) and noradrenaline (NA) had substantial effects (p < 0.05) on larval metamorphosis at concentrations ranging from 10 mu M to 100 mu M. 10 mu M beta-adrenergic receptor (AR) agonist isoproterenol showed the same inducement effect as that of NA and AD on metamorphosis, whereas the alpha-AR agonist phenylephrine had no significant effect at concentrations between 0.1 mu M and 100 mu M concentrations (p > 0.05). Furthermore, I mu M beta-AR antagonist propanolol, but not alpha-AR antagonist prazosin, depressed the larval metamorphosis induced by NA or AD. By immunocytochemistry, two cell bodies of beta-adrenergic-like receptor, C/A1, C/A2, were observed in the cerebral/apical ganglion of competent larvae. In addition, there were other immunoreactive dots near C/A1 and C/A2. The results of pharmacology and immunocytochemistry suggests that beta-adrenergic-like receptor located in the larval CNS, might play a considerable role in the larval metamorphosis of M meretrix by AD or NA. (c) 2006 Elsevier B.V. All rights reserved.

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鼠尾藻 [Sargassum thunbergii (Mert.) O’Kunte] 是北太平洋西部特有的一种暖温性大型经济褐藻,在我国沿海地区北起辽东半岛南至雷州半岛的硇州岛,都有广泛分布。鼠尾藻在食品和医药领域的应用开发在我国有悠久历史。近年来,随着水产动物养殖业迅速发展,其应用领域得到了进一步拓展,发现鼠尾藻是海参、鲍鱼等水产动物的优质天然饵料。 受海参和鲍鱼产业发展影响,鼠尾藻的市场需求量成倍增加。目前鼠尾藻的供应全部依赖自然资源。掠夺式的采收方式导致鼠尾藻的野生资源遭到了很大破坏,种群规模和数量不断减小,生态环境也发生了变化。近年来鼠尾藻供需矛盾已经非常突出,如何保护和有效利用该海藻资源已经成为海藻科研和产业界的一个重要话题。 以往对鼠尾藻的生态学和人工育苗技术方面的比较深入的研究工作很少,许多基础科学问题研究不够,人工繁殖技术没有很好地掌握,已经不能满足产业发展需求并限制了鼠尾藻应用价值的发挥。为此,有必要系统性研究鼠尾藻原生态环境、野生状态下生长发育的年际交替规律、鼠尾藻有性生殖过程、人工育苗方法途径、鼠尾藻吸收无机营养能力、以及在调控藻际菌群能力等基础科学技术问题,带动鼠尾藻饵料规模的良性健康扩大,并进一步推动海参和鲍鱼等水产业的发展。 本文以青岛汇泉角的鼠尾藻为基本实验材料,通过野外实地周年观察并结合实验室工作,对上述问题初步进行了初步探索,主要获得如下结果: (1)在青岛地区海滨岩石地带,全年都可观察到鼠尾藻藻体,藻体的形态大小和生理发育状况随季节变化表现出很大的差别性。夏季藻体黄褐色,初生分枝伸展,有次生分枝、生殖枝和气囊的发育,而冬季的藻体黑褐色,初生分枝粗短,没有次生分枝、生殖枝和气囊的发育。6月鼠尾藻出现有性生殖器官生殖托,到7月生殖托发育成熟,7月藻体最长,平均在50厘米左右,11月可观察到有性生殖和假根产生的幼苗。假根营养繁殖再生苗是鼠尾藻种群新苗源的主体,在维持种群自然繁衍和发展中起主导作用。 (2)有性生殖过程是鼠尾藻个体发育的大事件,精卵结合产生幼苗的潜力巨大,是开展未来规模化人工育苗的希望依托。鼠尾藻初生分枝长度和外形株间差异较大,每株鼠尾藻平均大约有20个初生分枝,约一半初生分枝可发育成熟,充分发育的初生分枝可产生30-50个次生分枝,每个次生分枝上又有大约20-30个生殖枝,每个生殖枝上生殖托数量一般为1-3个,雌托长度大多在3-5mm,雄托长度在10-15mm。生殖托的成熟度由基部向顶端递减。一个雌托排卵量平均为400多粒。以此计算,每株雌性鼠尾藻在生殖季节可产生200多万个卵。 卵从生殖窝孔排出后粘附于雌托表面,雄托排精时间稍晚于雌托挂卵时间,精子游动到卵周围与之结合完成受精过程。受精卵大约在受精后1小时分裂为两个大小相近的细胞,2小时后再进行第二次分裂,其中一个细胞横裂为两个细胞:一个细胞较大,另一个细胞较小,另一个细胞的分裂面与第一次分裂垂直,等分为两个细胞,随后细胞不断分裂。在受精后48小时左右,胚苗一端产生出假根。胚苗从雌托脱落的第一周内,尽管细胞数量增加较快,但新细胞体积减小,使得胚苗的体积增加不多。从第二周开始幼苗的体积出现明显的增加。此时,无机营养盐的有效补充对鼠尾藻幼苗培养长大是十分必要的。下海后的管理是保障幼苗成活的关键,此时常常发生脱苗现象。 (3)鼠尾藻对无机氮、磷都有较强的吸收能力,鼠尾藻从海水中吸收无机氮和无机磷的能力分别为75.1mg/kg/day和36.2mg/kg/day,鼠尾藻对氮、磷吸收的质量浓度比例接近5:1。 (4)鼠尾藻具有调节藻际微生物种群的能力,鼠尾藻对弧菌和总异养菌菌群都有一定程度的抑制作用,研究发现鼠尾藻抑制弧菌的能力存在种的差异,其中对鳗弧菌65#显示的抑制作用最强,鼠尾藻的抑菌能力的强弱还与其生理状态的好坏有显著关系。 通过上述研究结果,我们认为:鼠尾藻通过有性生殖过程培育种苗在理论上具有可行性,发展潜力很大。而解决幼苗后期培养中的脱苗问题、提高苗的成活率是下一步需要研究攻克的关键技术;假根营养繁殖再生苗源是维持该藻自然种群的主要方式,也是目前开展人工养殖获得健壮苗种的重要途径,连根采收方式对鼠尾藻野生资源破坏严重;建议野生鼠尾藻在7月底到8月初(水温27℃左右)采收(此时藻体生物量接近最大、并完成生殖过程),采用剪切方式保留假根和幼小的初生枝收获,该方式还可以应用到收获人工筏式养殖的鼠尾藻中,这对保证假根的完整性,大量获得下一个栽培季节的健壮新苗有实际意义;建议进一步开发鼠尾藻吸收富营养化物质、净化养殖环境水质的能力,以及对弧菌和总异养菌的抑制能力,建立海参、鲍鱼和鼠尾藻生态互补、环境友好的养殖模式,控制病害发生,提高水产品产量和质量。

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Studies on reproduction, hatchery management, and culture of Manila clams Ruditapes philippinarum were carried out in an attempt to optimize their culture conditions and techniques. Results from these studies led to the development of a three-phase culture method for Manila clam farming in northern China. The key components of the new method were: 1) early spawning and over-wintering indoors (greenhouse); 2) optimized larval culture conditions and techniques; 3) juvenile rearing in shallow, fertilized nursery ponds; 4) optimized stocking size and density and substrate for mudflat grow out. Broodstock were maturated indoors for a month from early April to early May. Primarily because of higher water temperatures in the greenhouse the clams spawned more than one month earlier than in the natural environment. From May to July, juveniles were reared for 1-2 months indoors to a size of 2.0-3.0 mm in shell length before being moved to outdoor, pre-disinfected, nursery ponds. Juveniles were then reared in the nursery ponds for one month to about 1.0 cm before being transferred to the mudflat for grow out. Juvenile clams in nursery ponds grew considerably faster than in the natural environment probably because of higher temperatures and more abundant natural food. During grow out, the clams were reared for 4-7 months until they reached a market size (3.0-3.3 cm). Juveniles produced after August were over-wintered in the greenhouse in which the water temperature was about 3 degrees C higher than that of the outdoor environment. Juveniles grew at an average rate of > 20 mu m day(-1), while in the natural environment no growth was observed during winter because of low temperatures. Juveniles in the greenhouse grew to 2-3 mm by the following March before being moved into outdoor nursery ponds. The three-phase culture method not only shortened the production period from spawn to market size from 24-36 months to about 10-14 months, but also prolonged the spawning season from 2 to 7 months, resulting in increased production of seed and market-size clams. Compared with the traditional method, the new method could increase the yield of market-size clams by 10-11 times, and increase the profit per ha mudflat by as much as 124 times and the profit per kg market-size clams produced by 13 times. (c) 2006 Elsevier B.V. All rights reserved.

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通过对青藏高原祁连山东段高寒小嵩草草甸主要植物种群物候特性的观测研究,采用聚类分析和主分量排序法将小嵩草草甸26种植物种群划分为不同的物候类群.利用相关系数排序法指出了影响不同物候期的主要生态因子依次是温度、降水量和日照时数.研究结果对物候资料积累、分析以及放牧管理具有指导意义.

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对海北定位站分布的金露梅灌丛草甸、矮嵩草草甸、藏嵩草沼泽化草甸3种高寒植被类型群落结构、感热(H)和潜热(LE)通量比较观测表明,3种植被类型年地上净初级生产力表现出矮嵩草草甸(318.600 g/m~2)>藏嵩草沼泽化草甸(258.341 g/m~2)>金露梅灌丛草甸(217.6 g/m~2).植物种类组成有矮嵩草草甸(54种)>金露梅灌丛草甸(47种)>沼泽草甸(24种).3种植被类型区近地表大气能量交换过程中,LE和H的月际变化明显,而且随植被类型的不同月际变化差异显著.3种不同植被类型在年内均表现出H+L E>0,表明在青海海北高寒草甸地区,太阳辐射强烈,近地层湍流输送明显,地表为-热源.3类型高寒草甸植被的年地上净生产量基本与波文比(β)呈现正效应,与LE+H呈现明显的反效应.植物种类组成基本与LE+H有反效应,与β呈明显的正效应.

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目的对蓼科(Polygonaceae)植物唐古特大黄(Rheum tanguticum Maxim、ex Balf.)染色体核型进行研究。方法采用常规压片方法,并结合显微摄影对染色体进行检测分析。结果唐古特大黄体细胞染色体数目为2n=22;核型公式为K(2n)=22=20m+2sm,核型为“1A”型。结论唐古特大黄染色体的核型属于较原始的类型。

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报道了西藏鱼类染色体多样性的研究结果。黑斑原■的染色体数目2n = 48 ,核型公式为20 m + 12sm + 10 st + 6 t;同时还存在2n = 42 与2 n = 44 两种类型,并据此认为黑斑原■不应是■科鱼类中的最特化种。西藏高原鳅、尖裸鲤、拉萨裸裂尻鱼、异齿裂腹鱼和拉萨裂腹鱼的染色体数目与核型公式分别为2n = 50 = 14 m + 4sm + 22 st + 10 t,2n = 86 = 24 m + 12 sm + 22 st + 18 t,2n = 94 = 22 m + 8 sm + 46 st + 18 t ,2n = 106 = 24 m + 26 sm +30 st + 26 t ,2n = 112 = 26 m + 24 sm + 28 st + 34 t ,在数目和核型或图像上有别于前人的报道。首次报道小眼高原鳅、高原裸鲤的染色体数目、核型及巨须裂腹鱼的核型公式,依次为2n = 50 = 16 m + 12 sm + 12 st + 10 t,2n = 94 =24 m + 14 sm + 22 sm + 34 t,2n = 102 = 20 m + 28 sm + 22 st + 16 t 。佩枯湖裸鲤的染色体数目2n = 66,是裂腹鱼类中最少的。双须叶须鱼染色体的数目则极多,2n = 424~432,甚为罕见,两者都有待进一步研究。 西藏鱼类的染色体多样性十分丰富, 表现出裂腹鱼类、鳅科和■科鱼类各属、种之间的差别以及种内不同居群甚至同一个体的细胞之间的差异。该特点可能与鱼类物种形成所处的不稳定环境有关。在探讨鱼类分类地位和演化关系时, 染色体组型有一定的可信度, 但只有当一个类群或属或种的染色体组型完全稳定时才可作为依据予以采用。

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A sensitive and efficient method for simultaneous determination of glutamic acid (Glu), gamma-amino-butyric acid (GABA), dopamine (DA), 5-hydroxytryptamine (5-HT) and 5-hydroxyindole acetic acid (5-HIAA) in rat endbrains was developed by high-performance liquid chromatography (HPLC) with fluorescence detection and on-line mass spectrometric identification following derivatization with 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC). Different parameters which influenced derivatization and separation were optimized. The complete separation of five neurotransmitter (NT) derivatives was performed on a reversed-phase Hypersil BDS-C-18 column with a gradient elution. The rapid structure identification of five neurotransmitter derivatives was carried out by on-line mass spectrometry with electrospray ionization (ESI) source in positive ion mode, and the BCEOC-labeled derivatives were characterized by easy-to-interpret mass spectra. Stability of derivatives, repeatability, precision and accuracy were evaluated and the results were excellent for efficient HPLC analysis. The quantitative linear range of five neurotransmitters were 2.441-2 x 10(4) nM, and limits of detection were in the range of 0.398-1.258 nM (S/N = 3:1). The changes of their concentrations in endbrains of three rat groups were also studied using this HPLC fluorescence detection method. The results indicated that exhausting exercise could obviously influence the concentrations of neurotransmitters in rat endbrains. The established method exhibited excellent validity, high sensitivity and convenience, and provided a new technique for simultaneous analysis of monoamine and amino acid neurotransmitters in rat brain. (C) 2008 Elsevier B.V. All rights reserved.

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针对目前基于Internet的遥操作机器人系统普遍完成任务简单,复杂度低,影响力有限的状况,本文将遥操作技术和Internet技术应用于具有高动态性、高协作性和高对抗性的机器人足球系统中,建立了基于Internet的遥操作机器人足球系统的体系结构,提供了该系统的软件设计方法,并针对网络通信设计了应用UDP协议进行连接和数据传输的方法.实际建立的基于Internet的3对3遥操作机器人足球系统验证了系统设计方法的可行性和有效性.通过实验验证了应用UDP协议进行连接和数据传输相对于应用TCP协议的优越性.

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优化问题是机器人在动态非结构环境下进行决策的关键问题之一。但是,优化算法通常具有较高的计算时间复杂度,尤其是在包括多种动力学约束的情况下,这限制了其在实时系统中的应用。受到人类智能发育过程及最新神经科学研究发现的启示,本文提出一种基于智能发育机制的场景驱动控制结构,对人的知识积累和应用知识的过程进行模拟,研究了与该控制结构相关的关键技术,包括智能发育算法、在线训练、知识的积累和检索方法等,并将这种控制结构应用于机械臂和机器人跟踪动态目标的行为优化问题之中。 首先,分析了现有人工智能方法在解决实时决策问题上的不足之处,提出用于解决机器人系统进行实时决策的基于智能发育机制的场景驱动控制结构(MDCDCA)。不同于通常的基于模型的控制,该控制结构通过在知识库中检索当前的状态,找到最相近的知识作为决策结果。如果检索出的知识不满足规定的判据条件,将激活常规的优化算法,优化结果同时作为在线训练数据对知识库进行训练。这种控制结构不同于通常的离线训练方法,它可以从空白的知识库开始,在线发育知识。 其次,研究了MDCDCA控制结构的核心部分:智能发育模块。提出采用增强分级判别回归算法(IHDR)作为智能发育引擎。IHDR能够有效地实现从状态空间(X)到行为空间(Y)的映射。研究了IHDR涉及的相关技术,如:X和Y 空间的定义方法,知识的存储、积累、更新、以及检索等。根据其不足之处,介绍了改进的IHDR算法,以提高其实时性和健壮性。 第三,研究了将MDCDCA控制结构应用于7自由度机械臂动态目标跟踪,并将遗传算法作为MDCDCA的在线训练引擎。不同于最短时间规划,提出将施加在每个关节的力矩与其最大力矩的比值作为遗传进化过程的评价函数。因此,优化结果产生一个“最小疼痛感”轨迹。这类似于人手臂的运动轨迹,更加适合于像服务机器人这种与人相互协作的机器人系统。仿真结果表明了经过遗传算法训练的MDCDCA可以有效地完成轨迹规划任务,并满足系统的实时性要求。 最后,将在线遗传算法训练的MDCDCA方法应用于移动机器人在三维动态空间的路径规划,该问题单纯采用遗传算法在实时性上难以得到保证,仿真及对比结果表明所提出方法的实时特性,也表明所提出方法可用于具有类似特性的实时系统。

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对额仁陶勒盖银矿床中石英的稀土元素、包裹体测温、包裹体成分、同位素、化学成分及红外光谱学特征等进行了研究,认为额仁陶勒盖银矿床属于浅成中温热液成因,早期成矿流体为岩浆热液,晚期成矿流体天水居主导地位,矿床形成于弱酸性-弱碱性条件下及还原环境中。石英的红外光谱学特征、石英的化学成分及形态是该银矿床重要的找矿矿物学标志。

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用基于Urey模型的量子化学从头计算.揭示Fe在FeCN6^3-和FeCN6^4-中的不同“自旋态”对同位素分馏行为的巨大影响.说明了只考虑“价态”的做法是不正确的,修正了关于“重同位素倾向于富集在高价化合物中”的这个广泛被接受的基本原理。并首次指出在压力导致自旋态变化的地质过程中,必定存在同位素分馏反常的复杂状况,是值得进一步研究的方向

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内蒙古盂恩陶勒盖矿床产于由黑云母斜长花岗岩和白云母斜长花岗岩组成的海西期盂恩花岗岩基的中心部位,矿体受东西向断裂控制。呈脉状。矿床主要有用组分为Pb,Zn,Cu,Ag,含Sn富In,Ga,Cd等分散元素,为一典型的多元素共生的多金属矿床。矿石铅同位素组成与赋矿的海西期花岗岩和矿区外围燕山期花岗岩的长石及全岩铅同位素组成明显不同,显示出矿石铅既不是由这两期岩浆活动提供的,也不是来自这两期花岗岩的改造,矿石铅与不同期次岩浆岩铅的对比显示,矿石铅来源于地幔岩浆分异,矿区深部可能存在地幔来源的岩浆岩。

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在滇黔相邻地区,二叠纪宣威组下部发育一层硅质页岩和碳质页岩。页岩层位稳定、分布广泛,与下伏 峨眉山玄武岩组上部凝灰岩层呈假整合接触关系。用迭代法恢复硅质页岩的Rb-Sr同位索古混合线,得到硅 质页岩的年龄为(255 4-12)Ma。这个年龄不仅支持地层古地磁研究结果,而且符合地层年代学研究结果,表明 Rb-Sr同位索古混合线年代学方法在中生代地层能够适用。这个年龄与普遍认为的峨眉山玄武岩主喷发期258 Ma从时代关系上相符,而且有效地约束了峨眉山玄武岩喷发的上限。