Those most vulnerable to heat stress are the elderly.

上了年纪的人最容易因受热而生病。

《牛津词典》

Imagine the situation in cities, where water scarcity combines with heat stress and air pollution to impair the health of millions, increasing the burden on health services that are already strained.

再想一想城市的情况，那里由于缺水，加上热应力和空气污染，会损害数百万人的健康，从而加重已经疲惫的卫生服务机构的负担。

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Rising sea levels, increasing salinization of water tables, and heat stress in association with air pollution are just some of the consequences of great concern in this part of the world.

海平面不断上升，潜水层日益盐化，以及与空气污染有关的热应力只是这个区域极令人担忧的一部分后果。

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The causes of heat stress include wearing heavy clothing, physical work or exercise, hot weather and high humidity.

VOA: special.2011.08.09

Experiments carried out by the scientists showed that a 2C rise in temperatures caused heat stress in the trees, shutting down the plants' photosynthesis.

BBC: NEWS | Science/Nature | Climate threat has plants quivering

They will bring some of their 12 cows to the county fair this year but leave a mother and her calf behind because of the stress of the heat.

MSN: Drought may mean fewer, smaller animals at fairs - US news | NBC News

The likely reason is that many of those dying in the heat are already seriously ill and even without heat stress would have died within the next 2 or 3 weeks.

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