A professor at Northwestern University proved conclusively that worry restricts the flow of the saliva, which leads to tooth decay.
一位西北大学的教授研究得出结论，忧虑拦阻人唾液的分泌，因此导致蛀牙。
2
The lifecycle of enterprise knowledge includes the periods of pregnancy, growth, maturity and decay, and there are knowledge flow and transformation in each period.
企业知识生命周期包括孕育期、成长期、成熟期和衰退期，每个时期都存在知识流动与转换。
3
The treatment can be used to describe the effect of cross angle and density ratio on the axial velocity decay in fully developed jet flow.