A country reporting zero cases over a period of 14 consecutive months is believed to have interrupted transmission.

人们认为，一个国家的零病例报告连续达到14个月就属于阻断了疾病传播。

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To be declared free of dracunculiasis, a country needs to have reported zero transmission and afterwards maintained active surveillance for at least three years.

要被宣布为无麦地那龙线虫病状态，国家需要具备零病例传播报告，并在此之后的至少三年内保持积极监测。

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As this kind of microstrip hairpin filter does not require cross coupling between the non-adjacent resonators of the filter to obtain transmission zero, the design procedure of the filter is simple.

由于这种类型的微带滤波器实现传输零点不需要通过滤波器非相邻谐振器间的交叉耦合来获得，因此，设计过程非常简单。

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