两种情况中，客户端的请求都可能被路由到透明的，或者未知的代理服务器(例如，一个数据中心的代理服务器或者远程服务器前端的一个反向代理服务器)。

In both cases, the client requests may be routed through transparent, or unknown, proxy servers (for example, a proxy server in a data center or a reverse proxy server in front of the remote server).

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对青少年而言，这个过程似乎从大脑后部开始，再移向前端。因此，至关重要的控制中心——前额叶皮层——就成了最后才被涉及的区域。

In teenagers, it seems that this process starts in the back of the brain and moves forward, so that the prefrontal cortex, that vital center of control, is the last to be trimmed.

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全新的动力装置以齿轮传动结构为特点，此结构允许前端风扇转速比中心部分慢3倍，优化了发动机各部分的速度。

The all-new powerplant features a geared architecture allowing the front fan to spin three times slower than the core, thus optimising the speed of each section of the engine.

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