Atelectasis be bibasal in pattern. Chest CT or Bronchoscopy may be necessary if the cause of atelectasis is not clinically apparent. Direct signs of atelectasis include displacement of interlobar fissures and mobile structures within the thorax, overinflation of the unaffected ipsilateral lobe or contralateral lung, and opacification of the collapsed lobe. Atelectasis may be an acute or chronic condition. In acute atelectasis, the lung has recently collapsed and is primarily notable only for airlessness. In chronic atelectasis, the affected area is often characterized by a complex mixture of airlessness, infection, widening of the bronchi (bronchiectasis), destruction, and scarring (fibrosis). The atmosphere
Cold and heat adaptations in humans with aborigines having a much lower sweat rate than whites. Social adaptations enabled early modern humans to occupy environments with temperatures that were drastically different from that of Africa. (Potts 1998). Culture enabled humans to expand their range to areas that would otherwise be uninhabitable. Humans have been able to occupy areas of extreme cold through clothing, buildings, and manipulation of fire. Furnaces have further enabled the occupation of cold environments. Australian aborigines only wear genital coverings for clothes, but studies have shown that the warmth from the fires they build is enough to keep the body from fighting heat