These constrictions arise from particular structures that compress the esophagus. Supraglottal pressure, with no constrictions or articulations, is equal to about atmospheric pressure. These are estuaries with shallow sill constrictions. There are segments of dilatations with trapped uncoagulated blood between the constrictions before complete occlusion. The arterial constrictions in moyamoya disease are unlike the constrictions in atherosclerosis. They are hollow and often have irregular constrictions. Typically, these constrictions are fully reversed by rapidly acting nitroglycerin. Relatively severe constrictions may require regular maintenance for decades to combat erosion. These became very distorted above the constrictions of the gorges. Delacroix found it significantly harder to sketch Arabic women, due to religious constrictions. These five constrictions are the result of the action of an impurity called "anava mala". The seeds pods are flattened and curved with constrictions between the seeds. Constrictions made by the lips are called labials. The gaster is large and without constrictions. Urban housing in India balances space constrictions and is aimed to serve the working class.