Fungal nail infections can be caused by three different types of fungus, alone or in combination. 1  Dermatophytes are a type of fungus that can grow on the skin, hair, and nails. 2  They don't invade the deeper tissues of the body. 3  The most common dermatophyte, Trichophyton rubrum, causes most cases of athlete's foot.
Negative Airflow. Negative airflow is the opposite of postive airflow its having more exhaust fans then intake fans, this is good because its always taking new air into the case, but then you have more dust because the intake is mostly coming from gaps in the case and then causing trapped air.
The air sacs permit a unidirectional flow of air through the lungs. Unidirectional flow means that air moving through bird lungs is largely 'fresh' air & has a higher oxygen content. In contrast, air flow is 'bidirectional' in mammals, moving back & forth into & out of the lungs.he air sacs permit a unidirectional flow of air through the lungs. Unidirectional flow means that air moving through bird lungs is largely 'fresh' air & has a higher oxygen content. In contrast, air flow is 'bidirectional' in mammals, moving back & forth into & out of the lungs.