鼎突多刺蚁热适应及运动行为的热依赖性

将鼎突多刺蚁(Polyrhachis vicina)分别置于15、20、25和30℃的恒温恒湿培养箱内,对其热适应及运动行为的热依赖性进行了研究。驯化2周后,采用温度梯度仪测量其热适应参数,并选用停顿频率(PF)、疾跑速度(SS)和最大持续运动距离(MDCCL)来衡量其运动能力。结果表明,驯化温度对鼎突多刺蚁的热适应和运动行为有极显著影响(P<0.01)。最适温度(PT)、临界低温(CLT)、临界高温(CHT)随驯化温度(AT)的升高而增大,最终适温为30.54℃,临界低温不低于3℃,临界高温不高于45℃;经过高温驯化的鼎突多刺蚁的运动能力显著大于经过低温驯化的个体运动能力,驯化温度与疾跑速度、最大持续运动距离呈显著的正相关,而与停顿频率呈极显著的负相关。     

热驯化和实验温度对鼎突多刺蚁运动能力的影响

以鼎突多刺蚁为实验对象,研究了热驯化和实验温度对其运动能力的影响。将成年的鼎突多刺蚁随机分成2组,分别置于20 ℃和30 ℃下驯化4周。经过驯化的动物分别在20 ℃或30 ℃观察、统计它们的运动能力指标——停顿频率、疾跑速度、最大持续运动距离。结果表明：驯化温度、实验温度以及二者的交互作用极显著影响了鼎突多刺蚁的运动速率;经过特定温度驯化的鼎突多刺蚁在该特定温度下的运动能力,相对于经过不同温度驯化而在相同温度下实验个体的运动能力有所提高。上述研究结果支持驯化有益假说。     

恒温和变温驯化对大蟾蜍蝌蚪热耐受性的影响

为了解大蟾蜍蝌蚪(Bufo gargarizans)的热适应性并验证最适性模型,将大蟾蜍蝌蚪分别在10、15、20℃和25℃4个不同恒温下及15.76-5.42℃的变温下驯养2周,利用温度梯度装置观察记录其最适温度、最高逃避温度和最高致死温度。结果表明,经过在10、15、20℃和25℃四个恒温及在15.76—5.42℃的变温下驯化,大蟾蜍蝌蚪的最适温度分别为(14.8±2.9),(17.2±3.8),(18.1±3.5),(19.6±2.5)和(15.8±2.2)℃;最高逃避温度分别为(27.6±1.9),(31.3±1.3),(32.5±0.8),(33.9±1.0)和(31.6±1.3)℃;最高致死温度分别为(32.9±1.6),(36.5±1.0),(37.9±0.9),(38.8±1.1)和(37.2±1.3)℃。驯化温度对大蟾蜍蝌蚪的最适温度、最高逃避温度和最高致死温度都有显著影响(P0.001)。驯化温度对大蟾蜍蝌蚪最适温度产生的影响比最高逃避温度和最高致死温度的小。温度的昼夜变化,都会呈现两峰或三峰分布,双峰环境实际上是具有同一标准误差的两个正常分布的混合体,这两个正常分布被一个峰间距所隔离。最适性模型预测:当呈双峰分布的温度的峰间距为17℃时,动物将出现3个适合度峰值。研究结果支持最适性模型。     

杂拟谷盗的热适应特性

为了解杂拟谷盗Tribolium confusum Jacquelin du Val的热适应特性,将杂拟谷盗分别于15,25和35℃下驯化2周后,用温度梯度仪测量在不同温度驯化下杂拟谷盗的最适温度、临界低温和临界高温。结果表明,驯化温度对杂拟谷盗最适温度、临界低温和临界高温的影响极显著(P<0.01),最适温度、临界低温、临界高温均随着驯化温度的升高而升高。最适温区的范围随着驯化温度的升高而扩大。驯化温度对杂拟谷盗最适温度的影响最大(0.317),对临界低温的影响(0.310)大于临界高温(0.255)。     

鼎突多刺蚁脑部组织切片方法初探及其脑部结构

膜翅目昆虫蚂蚁具有明显的多态现象,社会性生活中的分工亦非常明确。而作为蚁科中的鼎突多刺蚁还有着较高的药用保健价值。因此对其神经系统的研究有着重要的生物学意义。但蚂蚁脑部坚硬的外骨骼使得对其的组织学切片有一定难度。本试验即对鼎突多刺蚁的脑部组织切片方法进行了摸索和研究。     

泽陆蛙和饰纹姬蛙蝌蚪不同热驯化下选择体温和热耐受性

用泽陆蛙（Fejervarya limnocharis）蝌蚪和饰纹姬蛙（Microhyla ornata）蝌蚪做研究模型,检测热驯化（20 、25 和30 C）对选择体温（Tsel）、低温耐受性（CTMin）和高温耐受性（CTMax）的影响。结果显示,两种蝌蚪的Tsel既不受驯化温度的影响,也不存在种间差异;泽陆蛙蝌蚪的CTMin显著小于饰纹姬蛙蝌蚪,而CTMax和VTR则显著大于饰纹姬蛙蝌蚪;CTMin和CTMax随驯化温度的升高而升高,VTR则随驯化温度的升高而减小。研究结果表明,热驯化显著影响两种蝌蚪的CTMin、CTMax和VTR,而对两种蝌蚪的体温调定点无显著影响;这些热生物学特征对两种蝌蚪有效适应环境温度变化、利用资源、减少种间竞争具有重要的生态学意义。     

雄性山地麻晰选择体温、热耐受性及温度对食物同化和运动表现的影响

研究了捕自安徽宿州的成年雄性山地麻蜥（Eremias brenchleyi）选择体温、热耐受性、温度对食物同化和运动表现的影响。结果显示：①选择体温、临界高温和临界低温的平均值分别为33.7、43.6和3.3℃。②环境温度在26－38℃时,对山地麻蜥食物通过时间、摄食量、表观消化系数（ADC）、同化效率（AE）和运动表现有显著的影响;在26－30℃时食物通过时间随温度升高而缩短,通过30℃则随温度升高而延长;在26和28℃时,摄食量、ADC和AE均小于更高温度的对应值。③体温在19－34℃,蜥蜴的疾跑速随体温上升而加快,31和34℃时最快,超过34℃后随体温升高而减慢;31和34℃时的持续运动距离最长,超过36℃后随体温升高而显著缩短,但体温19－36℃蜥蜴的持续运动距离无显著差异;19－34℃蜥蜴的路道停顿次数较少,无显著差异,超过34℃后显著增加。     

中华花龟幼体热耐受性、体温昼夜变化和运动表现的热依赖性

为研究中华花龟(Ocadia sinensis)幼体的热耐受性和运动表现热依赖性，设计了具有和缺乏温度梯度两种热环境，研究幼龟体温的昼夜变化。高、低温耐受性分别用临界高温和临界低温表示，体温为泄殖腔温度，水温和气温分别是幼龟所处位置的水温和1cm高气温。临界高温和临界低温分别为41．9℃和1．8℃。在有温度梯度的热环境中，体温、水温和气温平均值有显著的昼夜差异，水温和体温的日平均值无显著差异，两者均大于气温的日平均值。在缺乏温度梯度的热环境中，体温、气温和水温平均值亦有显著的昼夜差异，但气温、水温和体温的日平均温度无显著差异。温度梯度是幼龟进行体温调节不可或缺的条件，选择体温有显著的昼夜变化，最大值和最小值分别为29．2℃和25．4℃。在02：00—06：00时间段内，幼龟选择体温明显较低，其它测定时刻的选择体温无显著差异。幼龟各测定时刻的平均体温与平均气温和水温均呈正相关。处于温度梯度中幼龟特定气温的体温比处于缺乏温度梯度中的幼龟高3．7℃，这种差异是前者利用温度梯度进行体温调节的结果；处于不同热环境中幼龟特定水温的体温无显著差异。体温显著影响幼龟的运动表现。18—39℃体温范围内，疾跑速随体温增加而增加，36℃和39℃体温的幼龟疾跑速最大；体温达到41℃时，疾跑速显著下降。体温较高的幼龟的最大持续运动距离大于体温较低的幼龟。偏相关分析显示，疾跑速与最大持续运动距离和停顿次数呈显著的正相关，停顿次数与最大持续运动距离呈负相关。     

南方鲇幼鱼的热耐受特征

为了研究不同驯化温度对南方鲇（Silurus meridionalis Chen）幼鱼热耐受性特征的影响,在水温为10 ℃、20 ℃和30 ℃的条件下,对南方鲇幼鱼（（16.9±0.3）g）进行2周的驯化,以1 ℃·h^-1的变温速率连续观测实验鱼的耐受温度,各驯化温度下的最大临界温度（CT_max）、最大致死温度（LT_max）、最小临界温度（CT_min）和最小致死温度(LT_min）分别为3413 ℃、3822 ℃、39.41 ℃;34.84 ℃、38.63 ℃、39.53 ℃;4.88 ℃、5.90 ℃、9.80 ℃;4.12 ℃、5.03 ℃、8.29 ℃。结果表明：最大临界温度和最大致死温度随驯化温度的升高而增大,最小临界温度和最小致死温度随驯化温度的降低而减小;经计算,南方鲇幼鱼在各驯化温度下的温度耐受幅分别为29.25 ℃、32.32 ℃和29.61 ℃;在10 ℃～20 ℃的驯化温度范围内高、低温驯化反应率分别为0.41和0.12,而在20 ℃～30 ℃驯化温度范围内高、低温驯化反应率分别为0.10和0.39;热耐受区域面积为617.5 ℃²;证明南方鲇幼鱼的热耐受性明显有赖于驯化温度。     

黑翅土白蚁触角感器的扫描电镜观察

【目的】通过黑翅土白蚁Odontotermes fomosanus(Shiraki)幼蚁、工蚁、兵蚁触角感器种类、数量及分布的研究,分析不同龄幼蚁、工蚁和兵蚁的触角感器特征,为进一步研究触角感器发育特点及不同个体的行为分化机制提供参考。【方法】通过扫描电镜观察触角形态,分析触角节数、感器种类、数量及分布特征。【结果】工蚁、兵蚁、幼蚁个体触角长度差异显著,触角长度顺序:工蚁>兵蚁>3龄幼蚁>2龄幼蚁>1龄幼蚁;触角感器共有9种类型,分别为短毛形感器、长毛形感器、短刺形感器、长刺形感器、锥状B?hm氏鬃毛、球状钟形感器、刺突状钟形感器、球状钟形感器与刺突状钟形感器中间型、长刺具泡状感器。工蚁、兵蚁缺少长刺具泡状感器。幼蚁触角感器种类和数量随龄数而增加,1龄幼蚁具7种感器,缺少球状钟形感器和球状钟形感器与刺突状钟形感器中间型2种类型;2龄幼蚁具有8种感器,缺球状钟形感器;3龄幼蚁具有全部9种类型感器。【结论】黑翅土白蚁幼蚁、工蚁、兵蚁触角节数和感器显著差异,可作为幼蚁龄数以及非生殖品级判别的形态指标,应用于白蚁非生殖品级行为多型等相关研究。     

Non-equilibrium molecular dynamics study on radial thermal conductivity and thermal rectification of graphene

In the present study, the radial thermal rectification and thermal conductivity of the graphene were investigated by non-equilibrium molecular dynamics simulation and then corrected by quantum correction to make it closer to the fact. The Optimised three-body Tersoff potential is employed in order to simulate the interactions between the carbon atoms in the graphene sheet. A circular region in the centre and the one at the graphene edge are selected as hot and cold bath to generate radial temperature gradient. It is observed that the heat current passes through radially inward direction than outward with the same temperature gradient and hence there is a radial thermal rectification in graphene. Also, temperature distribution and heat flux are theoretically introduced as a function of distance from the graphene centre and then it is confirmed by the molecular dynamics simulation data. Finally, the influence of temperature gradient and size of graphene on radial thermal rectification and the impact of size on the radial thermal conductivity is investigated.     

Evaluating thermal resource partitioning

Summary The field thermal biology of sympatric Anolis cooki and A. cristatellus were evaluated in January and in August in desert scrub forest at Playa de Tamarindo near Guanica, Puerto Rico. Data on randomly positioned copper models of lizards, each equipped with a built-in thermocouple, established null hypotheses about basking frequency and operative temperatures (T _e) against which the behavior and body temperatures (T _b) of live lizards were evaluated. Both species exhibited non-random hourly basking rates (more marked in cristatellus than in cooki), and cristatellus was virtually inactive during the warm mid-day hours. The relationship between lizards' T _b and randomly sampled T _e differed between the species: cristatellus's mean T _b was 2° to 3° C lower than randomly sampled mean T _e in both months, whereas cooki's mean T _b was slightly higher than mean T _e in January and slightly lower in August. Although cooki's mean T _b was higher than that of cristatellus in both months, the T _b's of the two species overlapped substantially over an annual cycle. Given the similarities in their field active T _b and the low thermal heterogeneity among microsites at Playa de Tamarindo, these species appear not to partition the thermal environment there in a coarse-grained way. Instead, the relatively small differences in their field active T _b probably result from small differences in their use of similar microhabitats within their mutually exclusive territories. Thermal resource partitioning by territorial animals is unlikely unless thermal heterogeneity is coarse-grained in relation to territory size.     

A comparison of the thermal stability and substrate binding constants of prolyl-tRNA synthetase from Phaseolus aureus and Delonix regia

Pro-tRNA synthetase from P. aureus and D. regia was protected against thermal denaturation by various substrates; the kinetics of this protection was investigated. The affinity of substrates for each synthetase was studied by a thermal inactivation technique. In the presence of ATP, Pro and several Pro-analogues were bound to each enzyme more efficiently than when ATP was absent. The efficiency of imino acid analogue binding, relative to that of Pro, was greater when ATP was absent. Pyrrolidine and 3-pyrroline were able to bind to the enzyme only in the presence of ATP. The ratio of the ATP/Pro binding constants for the Delonix enzyme was greater than that for the Phaseolus enzyme. Values for several thermodynamic parameters involved in substrate binding were determined for each synthetase. The results are discussed in relation to the order of substrate binding and the known differences in substrate specificity between the enzymes from P. aureus and D. regia.     

虎纹蛙选择体温和热耐受性在个体发育过程中的变化

体温是影响变温动物表现的最重要生理学变量。检测了国家二级保护动物虎纹蛙的雌性亚成体、雄性亚成体、幼体和蝌蚪这4个发育阶段的选择体温和热耐受性。单因子方差分析表明,虎纹蛙选择体温、耐受低温、耐受高温和温度耐受范围的组间差异均显著,幼体的选择体温(24.13℃)显著低于雌性亚成体(28.06℃)、雄性亚成体(29.27℃)和蝌蚪(28.23℃),雌性亚成体、雄性亚成体和蝌蚪之间差异不显著;幼体的耐受低温(13.85℃)显著高于雌性亚成体(11.27℃)、雄性亚成体(10.84℃)和蝌蚪(10.74℃),雌性亚成体、雄性亚成体和蝌蚪之间差异不显著;幼体具有显著低的耐受高温(35.48℃)、蝌蚪具有显著高的耐受高温(43.31℃),雌性亚成体(39.55℃)和雄性亚成体(39.02℃)的耐受高温差异不显著;幼体(21.62℃)具有显著小的温度耐受范围、蝌蚪(32.58℃)具有显著大的温度耐受范围,雌性亚成体(28.28℃)和雄性亚成体(28.18℃)的温度耐受范围差异不显著。虎纹蛙幼体和亚成体体温和水温之间在降温速度和升温速度的相关关系均显著。用回归剩余值去除水温变化速度对体温变化的影响,双因子方差分析(降温和升温速度为重复检验设置)表明,幼体的体温变化速度显著大于亚成体,两性亚成体间差异不显著;温度变化类型(降温和升温)和两因子的交互作用对体温变化的影响不显著。基本热生态位分离和体温调节能力的发育限制是形成上述现象的最可能的原因。     

Maximum thermal tolerance trades off with chronic tolerance of high temperature in contrasting thermal populations of Radix balthica

Thermal adaptation theory predicts that thermal specialists evolve in environments with low temporal and high spatial thermal variation, whereas thermal generalists are favored in environments with high temporal and low spatial variation. The thermal environment of many organisms is predicted to change with globally increasing temperatures and thermal specialists are presumably at higher risk than thermal generalists. Here we investigated critical thermal maximum (CT_max) and preferred temperature (T_p) in populations of the common pond snail (Radix balthica) originating from a small‐scale system of geothermal springs in northern Iceland, where stable cold (ca. 7°C) and warm (ca. 23°C) habitats are connected with habitats following the seasonal thermal variation. Irrespective of thermal origin, we found a common T_p for all populations, corresponding to the common temperature optimum (T_opt) for fitness‐related traits in these populations. Warm‐origin snails had lowest CT_max. As our previous studies have found higher chronic temperature tolerance in the warm populations, we suggest that there is a trade‐off between high temperature tolerance and performance in other fitness components, including tolerance to chronic thermal stress. T_p and CT_max were positively correlated in warm‐origin snails, suggesting a need to maintain a minimum “warming tolerance” (difference in CT_max and habitat temperature) in warm environments. Our results highlight the importance of high mean temperature in shaping thermal performance curves.     

Critical thermal maxima and minima of Macrobrachium rosenbergii (Decapoda: Palaemonidae)

1. Critical thermal maxima (CTMax) and minima (CTMin) were determined for postlarvae and juveniles of Macrobrachium rosenbergii acclimated at 20, 23, 26, 29 and 32±1°C. 2. At each acclimation temperature the CTMax and CTMin for postlarvae were 37.3, 38.3, 39.0, 41.0, 41.6°C and 10.0, 11.0, 13.0, 14.8, 16.8°C respectively and for juveniles 36.5, 38.4, 39.2, 41.5, 42.0 and 10.5, 11.3, 13.3, 14.6, 16.4°C respectively. 3. We found no indication of significant differences (P>0.05) in the CTMax and CTMin of the prawn postlarvae and juveniles. 4. The zone of thermal tolerance base on the CTMax and CTMin boundaries for postlarvae was 821.2°C² and 816.9°C² for juveniles, showing a high degree of eurythermality. To cultivate this species it should be done in no less than 16°C (CTMin) and below 42°C.