相关实验视频
Updated: Jul 3, 2025

07:16
Thermal Limits Determination for Zooplankton Using a Heat Block
Published on: November 18, 2022
1.4K
重置热极限:10岁白鱼显示明显但可逆的热可塑性
Theresa A Weber1, Angelina M Dichiera2, Colin J Brauner1
1Department of Zoology, The University of British Columbia, Vancouver, British Columbia, Canada.
Journal of thermal biology
|February 10, 2024
概括
临灭绝的白在温暖的适应后表现出更高的耐热性,但这种能力甚至在返回较低温度后也可能带来持久的代谢成本.
科学领域:
- 生理生态生态学 生理生态学
- 保护生物学 保护生物学
- 水生生态毒理学 水生生态毒理学
背景情况:
- 湿热植物经常通过暴露于热量来提高热耐受性.
- 人们对鱼类回归较低温度后温暖适应的持久影响知之甚少.
- 热应激可以不成比例地影响受威胁和危物种.
研究的目的:
- 研究温暖适应对临灭绝的白 (Acipenser transmontanus) 热耐受性和压力反应的持久影响.
- 评估长寿,危鱼类的热可塑性和潜在的长期成本.
主要方法:
- 在未成年白鱼中多次测量临界热最大值 (CTmax).
- 监测的生理压力指标:血红素,血红蛋白,血皮质醇.
- 在控制温度下在适应和适应后的时间内评估了脏和肝脏的体质指数.
主要成果:
- 温暖适应的鱼在耐热性 (∼3.1°C) 中显著增加.
- 在返回较低的温度后,热耐受性下降,但与对照组相比仍然很高 (≤1.9°C低).
- 温暖的适应导致肝脏大小持续减少45%,表明能量使用和新陈代谢发生了变化.
结论:
- 临灭绝的白表现出了显著的热适应能力.
- 温暖的适应可能会给人带来持续的代谢成本,以减少肝脏大小为标志,即使在重新适应较低温度后也是如此.
- 需要进一步的研究来了解这种物种中热可塑性的长期能量权衡.
相关概念视频
Responses to Heat and Cold Stress
13.5K
Every organism has an optimum temperature range within which healthy growth and physiological functioning can occur. At the ends of this range, there will be a minimum and maximum temperature that interrupt biological processes.
13.5K
Thermal Stress
2.4K
If the temperature of an object is changed while it is prevented from expanding or contracting, the object is subjected to stress. The stress is compressive if the object expands in the absence of constraint and tensile if it contracts. This stress resulting from temperature change is known as thermal stress. It can be quite large and can cause damage. To avoid this stress, engineers may design components so they can expand and contract freely. For instance, on highways, gaps are deliberately...
2.4K
Plastic Behavior
197
A material's elastic behavior is characterized by the disappearance of stress once the load is removed, allowing the material to return to its original state. However, when stress surpasses the yield point, yielding commences, marking the onset of plastic deformation or permanent set. This change from elastic to plastic behavior is influenced by the peak stress value and the duration before the load is removed. An intriguing observation occurs when a specimen is loaded, unloaded, and...
197
Thermal Expansion
4.4K
The expansion of alcohol in a thermometer is one of many commonly encountered examples of thermal expansion, which is the change in size or volume of a given system as its temperature changes. The most visible example is the expansion of hot air. When air is heated, it expands and becomes less dense than the surrounding air, which then exerts an upward force on the hot air to, for example, make steam and smoke rise, and hot air balloons float. The same behavior happens in all liquids and gases,...
4.4K
Thermal Strain
1.0K
Thermal strain is a concept that arises when we consider how temperature changes affect structures. Unlike the conventional assumption that structures remain constant under load, real-world scenarios often involve temperature fluctuations that can significantly impact these structures. Consider a homogeneous rod with a uniform cross-section resting freely on a flat horizontal surface. If the rod's temperature increases, the rod elongates. This elongation is proportional to the temperature...
1.0K
Thermal expansion and Thermal stress: Problem Solving
1.2K
San Francisco's Golden Gate Bridge is exposed to temperatures ranging from -15 °C to 40 °C. At its coldest, the main span of the bridge is 1275 m long. Assuming that the bridge is made entirely of steel, what is the change in its length between these temperatures?
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in...
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in...
1.2K

