不同麻醉剂量灌喂对南方鲇幼鱼代谢的影响

绝大多数的鱼类餐后代谢即特殊动力作用(SDA)研究都是以实验条件下能够主动摄食的鱼类为对象,近年来麻醉灌喂方法越来越多地用于不主动摄食鱼类的相关研究,而目前专门评价麻醉灌喂方法的文献资料却不多见.本研究为了考察麻醉灌喂对南方鲇(Silurus meridionalis Chen)幼鱼SDA的影响,采用4、7、10 g/L的不同剂量麻醉剂间氨基苯甲酸乙酯甲磺酸盐(MS-222)处理,以主动摄食组为对照,均灌喂10 %南方鲇幼鱼体重的泥鳅(Misgurus anguillicanndotus),连续48 h(1次/2 h)测定各组实验鱼的耗氧率.结果显示,各实验组的SDA参数之间,除10 g/L麻醉灌喂组的摄食代谢峰值比率与对照组存在显著差异外(p＜0.05),其它参数如静止代谢率、SDA时间、峰值达到时间、摄食代谢峰值、SDA总能量和SDA系数各实验组之间均无显著差异(p＞0.05).上述结果表明,麻醉和灌喂操作对南方鲇幼鱼的SDA过程无明显影响,该方法不仅适用于南方鲇摄食代谢的研究,还将有助于获取不主动摄食鱼类的相关资料.     

摄食对肉食性乌鳢和草食性鳊幼鱼运动及行为特征的影响

为考查食性和摄食对鱼类运动和行为的影响及两者交互作用,以肉食性鱼类乌鳢(Channa argus)幼鱼和草食性鱼类鳊(Parabramis pekinensis)幼鱼为研究对象,在(25±1)℃的条件下分别测定了实验鱼的自发运动、快速启动能力和隐匿行为的相关指标。结果显示,乌鳢和鳊自发运动速度分别为(9.64±0.67),(8.40±0.26)cm·s-1,用于运动的时间分别为(15.15±3.69)%,(13.39±3.50)%,均无显著差异;快速启动的最大线速度分别为(1.64±0.18),(1.99±0.17)mm·ms-1,最大加速度分别为(0.21±0.03),(0.31±0.03)mm·ms-2,鳊显著高于乌鳢(p0.05);进入隐匿场所时间比分别为(2.81±0.91)%,(0.15±0.12)%,乌鳢显著高于鳊(p0.05);摄食对乌鳢和鳊的自发运动水平和快速启动能力均无显著影响,仅导致乌鳢进入隐匿场所时间比显著下降(p0.05)。研究结果提示,乌鳢和鳊幼鱼均具有较低的自发运动水平、较高的快速启动能力和较低隐匿行为,这一方面与乌鳢幼鱼的捕食方式和生活环境相适应,另一方面也与鳊幼鱼的觅食和避敌方式有关。     

摄食水平对叉尾斗鱼特殊动力作用的影响

【目的】考察摄食水平对野外条件下生存的叉尾斗鱼(Macropodusopercularis)特殊动力作用(Specificdynamicaction，SDA)的影响。【方法】在水温(26.9±0.6)℃且水体溶氧量大于7.0mg·L-1的条件下，用混合红线虫为饵料饲喂叉尾斗鱼，并以空腹的叉尾斗鱼作为摄食水平为0的假摄食组；用鱼类呼吸代谢测定仪测定不同摄食水平条件下（即饲喂量分别约为鱼体质量的1.5%，3.5%，4.5%和6.5%）叉尾斗鱼的耗氧率，计算SDA的相关参数。【结果】1)在不同摄食水平条件下，叉尾斗鱼的耗氧率随着摄食后时间延长均呈现先快速上升后下降的变化趋势。2)随着摄食水平的提升，叉尾斗鱼的SDA时间逐渐延长，SDA总量逐渐上升，摄食水平对这两个参数的影响均具有统计学意义(p＜0.05)。3)摄食水平对摄食代谢峰值、摄食代谢峰值比率和峰值到达时间的影响均无统计学意义。【结论】叉尾斗鱼SDA时间随摄食水平的增加而明显延长，但摄食代谢峰值无明显变化；这一特征暗示该鱼种通过增加消化时间来进行食物消化。相对较短的峰值到达时间和SDA时间则暗示了叉尾斗鱼具有较快的消化速率，有利于该鱼种在短时间内再次摄食以获取更多的食物资源。     

力竭运动训练对锦鲫幼鱼无氧代谢能力的影响 (动物科学)

将锦鲫(Carassius auratus)幼鱼20尾随机平均分成训练组和对照组,在25℃水温下每天饱足投喂1次;其中训练组实验鱼持续2周进行强度为每天2次的力竭运动训练;随后分别测量实验鱼力竭运动后的耗氧率并计算过量耗氧(EPOC);待力竭运动恢复8 h后再分别取样测量肌乳酸、肝乳酸的含量和肌肉中乳酸脱氢酶(LDH)、柠檬酸合成酶(CS)的活性。研究发现,力竭运动训练组与对照组的EPOC分别为(166.2±7.2)、(108.0±6.2)mg.kg-1,训练组显著高于对照组(p<0.05);肌乳酸含量分别是(17.4±0.8)、(25.4±1.7)μmol.g-1,训练组显著低于对照组(p<0.05);训练组实验鱼的肝乳酸含量、LDH和CS的活性与对照组之间均无显著差异。研究表明力竭运动训练有助于提高锦鲫幼鱼的无氧代谢能力;无氧代谢能力的提高可能与乳酸清除速率加快有关。     

不同溶氧水平下锦鲫的运动和代谢适应对策

为考查广氧性鱼类锦鲫(Carassius auratus)在不同水体溶氧(DO)水平下的运动和能量代谢适应对策,在25 ℃对水体DO分别为0.5、1、2、4 mg·L-1以及接近100%饱和溶氧浓度的8 mg·L-1水平下锦鲫幼鱼静止代谢率(RMR)、活跃代谢率(AMR)、临界游泳速度(Ucrit)及不同游泳速度下的单位位移能量消耗(COT)进行了测定.研究发现锦鲫的Ucrit和AMR均随着DO的下降而呈下降趋势,各处理组均有显著差异(p<0.05),两者在低DO端即4～1 mg·L-1下降更为剧烈,且AMR下降速率明显大于Ucrit;RMR在DO从8～1 mg·L-1时没有显著变化,但1 mg·L-1以下随DO的下降线性下降(p<0.05);各实验处理组锦鲫随游泳速度的上升代谢率上升;低DO实验组(0.5、1和2 mg·L-1实验组)各游泳速度下COT无显著差异,而高DO实验组(4和8 mg·L-1实验组)COT随游泳速度的上升而显著上升,消除RMR影响后各实验组单位位移净能量消耗(COTnet)随游泳速度上升均显著上升(p<0.05);在较低的游泳速度下,较低的DO实验组往往比同一游泳速度下的较高DO实验组锦鲫有更高的能量利用效率(低COT值,p<0.05),但随着游泳速度上升不再有该趋势.研究提示锦鲫在不同DO水平下采取不同的运动和能量代谢对策以适应不同环境溶氧条件.     

不同时间间隔重复力竭运动对南方鲇幼鱼耗氧率的影响

考察我国特有暖水性伏击取食鱼类南方鲇(Silurus meridionalis Chen)的重复运动能力,检验力竭运动后的恢复状态是否对下一次力竭运动代谢恢复过程产生影响.实验仪器采用自制流水式呼吸仪(专利号ZL 200520010481.0);南方鲇幼鱼选用体重为17.64～48.21 g,n=40;在(25.0±1.0)℃条件下,测定了不同时间间隔即10 min重复3次、30 min重复2次和24 h重复2次条件下,重复力竭性运动(驱赶至力竭)后南方鲇幼鱼的耗氧率(Vo2)恢复过程.研究发现在本实验条件下,南方鲇幼鱼静止耗氧率(Vo2rest)为(2.39±0.13)～(2.83±0.31)mg·min-1·kg-1,耗氧率峰值(Vo2peak)为(8.36±0.26)～(10.39±0.44)mg·min-1 ·kg-1,运动后过量耗氧(EPOC)总量为(66.31±6.37)～(88.89±4.61)mg·kg-1.力竭运动后20～30 min耗氧率可达一稳定状态,经24 h恢复回落到运动前水平.无论间隔时间长短,各处理组第二次力竭运动均导致恢复速率的显著增加(p<0.05),但耗氧峰值和恢复过程的过量耗氧没有显著变化.研究提示力竭性运动能诱导出南方鲇幼鱼的最大耗氧率.     

水流刺激对宽鳍鱲幼鱼的游泳和代谢的影响

为考查水流刺激对宽鳍鱲(Zacco platypus)幼鱼游泳能力和代谢的影响,将60尾实验鱼随机均分为处理组(流水组)和对照组(静水组);然后在相同的条件下饲养6周,分别于(20±1.0)℃条件下进行临界游泳速度(Ucrit)、静止代谢率(RMR)和活跃代谢率(AMR)的测定,并计算不同游泳速度下的代谢率(MR)、单位位移耗能(COT)和最适游泳速度(Uopt)。结果显示,对照组和处理组的RMR分别为(153.72±7.41)、(197.85±8.00)mgO2·kg-1·h-1,对照组显著低于处理组(p0.05);对照组和处理组的Ucrit分别为(62.90±2.84)、(75.50±4.27)cm·s-1,对照组亦显著低于处理组(p0.05);对照组和处理组的AMR没有显著差异;给定游泳速度下对照组的MR显著高于处理组(p0.05);在较低游泳速度下对照组的COT亦显著高于处理组(p0.05),但这种差异随着游泳速度的上升显著降低(p0.05);对照组和处理组的Uopt分别为54.00、44.00cm·s-1。研究结果表明,持续水流刺激显著提高了实验鱼的游泳能力,与之上升的游泳效率相关,但代价是维持能量消耗的增加。     

饥饿和摄食状态下大黄鱼幼鱼的能量收支

在25±1℃的室温下,测定了在不同摄食水平(1.2%,2.5%m/m)下大黄鱼幼鱼SDA的三个主要参数:SDA总耗能分别为263.4 J/g和467.7 J/g;SDA持续时间分别为8 h和14 h;峰值分别为2.85 mgO2/g.h和3.23 mgO2/g.h.得到了在饱食状态下的能量收支方程:100C=64.5R+20.7G+10.6F+4.2U.饥饿状态下大黄鱼幼鱼排泄能与温度成线性关系,代谢能与温度之间为二次函数关系.同时对饱食状态和饥饿状态下的能量收支进行了比较.     

消化活动与短期饥饿对不同摄食习性鱼类最大代谢的影响

为考察不同摄食习性鱼类在消化活动期间及短期饥饿后最大代谢的变化情况，在24 ℃条件下，测定南方鲇(Silurus meridionalis)、锦鲫(Carassius auratus)、丁鱥(Tinca tinca)和鲢(Hypophthalmichthys molitrix)的幼鱼在消化活动期间及短期饥饿后的最大代谢率(maximum metabolic rate，MMR)。研究结果显示：1) 在种间水平上，积极摄食的锦鲫在消化活动时的MMR比其他鱼类在消化活动时的MMR更高，数据差异具有统计学意义(p<0.05)；伏击取食的南方鲇在短期饥饿后的MMR比其他摄食习性鱼类在短期饥饿后的MMR更低，数据差异具有统计学意义(p<0.05)。2) 在种内水平上，锦鲫在消化活动时的MMR与对照组相比有统计学意义上的提升(p<0.05)，南方鲇、丁鱥和鲢在消化活动时的MMR与对照组相比变化不明显；短期饥饿后的南方鲇MMR与对照组相比有统计学意义上的下降(p<0.05)，锦鲫、丁鱥、鲢在短期饥饿后的MMR与对照组相比变化不明显。积极摄食的锦鲫心-鳃系统能力强，能够快速消化食物，因此在消化活动时MMR明显上升；伏击取食的南方鲇因采取典型的消化优先模式，故消化活动期间MMR有所降低；丁鱥和鲢单次摄食量少，因而摄食后MMR上升不明显。在经历短期饥饿后，4种鱼类均下调自身生理功能以降低能量消耗。     

急性降温对青鱼幼鱼游泳能力的影响

为了研究急性降温对鱼类的行为及代谢的影响,本实验设置25℃→25℃,25℃→15℃,15℃→15℃(驯化温度→实验温度)3个温度组,采用自制鱼类能量游泳装置测定了青鱼(体长8.87±0.75cm,体重11.86±3.60g)临界游泳速度(Ucrit)、耗氧率(MO2)以及疲劳后的恢复耗氧率.研究结果表明:青鱼在3个温度组Ucrit分别是11.32±0.29BL/s、8.04±0.38BL/s和7.73±0.25BL/s,急性降温(25℃→15℃)组的Ucrit是15℃→15℃组的96.2%,降低了3.8%,差异性不显著(P0.05),急性降温在短时间内抑制青鱼幼鱼游泳速度,影响不显著;MO2随着流速的增加而增大,耗氧率与流速关系分别为25℃→25℃:MO2=49.138U+365.990,R2=0.995;15℃→15℃:MO2=42.886U+315.002,R2=0.972;25℃→15℃:MO2=37.265U+259.987,R2=0.973;随着温度升高,耗氧率增大,急性降温对鱼类的耗氧率有抑制作用;疲劳后继续测定耗氧状况,90min内恢复耗氧率均呈先降低后逐渐趋于平稳,恢复耗氧率分别为25℃→25℃:73.14 mgO2/kg,25℃→15℃:102.47mgO2/kg,15℃→15℃,89.38mgO2/kg.研究表明:急性降温对青鱼幼鱼游泳特性具有显著的影响,并且对其行为产生胁迫作用,研究有利于为鱼道的建设提供数据资料,对鱼类的保护具有重要的意义.     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to