gravity filtration process

Teen years are a critical time because the mammary glands are undergoing rapid growth during that period, said Catherine Berkey, a biostatistician at Harvard Medical School.

青春期是尤其要注意的阶段，因为此时乳腺正出于一个快速发育的阶段，哈佛大学医学院生物统计学家凯瑟琳解释道。

Spending hours on the Internet likely contributes to weight gain by taking time away from physical activity, according to Berkey's team.

依照伯克利研究小组的说法，花数小时的时间上网导致体重增加的原因是因为体力活动的时间减少了。

Berkey warned that the behaviours may unnoticed as causes of gradual weight gain.

伯基警告说,该行为可能被遗漏的原因循序渐进的体重增加.

the effects over 1 year were modest, berkey's team points out.

伯克利的研究小组指出1年的时间效应不是很显著。