We show that all subvarieties of left regular bands are closed in the variety of all bands. We also show that all subvarieties of left seminormal bands are saturated in the variety of all bands which shows that, in the category of all bands, any epi from a left seminormal band is surjective.

中文翻译：

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Epimorphisms, dominions 和品种的乐队

我们表明左规则带的所有子变体在所有带的种类中都是封闭的。我们还表明，左半正规带的所有子变体在所有带的种类中都饱和，这表明，在所有带的类别中，来自左半正规带的任何外延都是满射的。