: Pediatric primary chronic headache disorders are often associated with sensitivities to light (photosensitivity) and sound (phonosensitivity) that may trigger or worsen headache pain. These sensory sensitivities may result in changes to activity participation or environmental modifications to avoid visual and auditory stimuli. Over time, avoidance behaviors can inadvertently increase functional disability, suggesting the importance of their thorough consideration.
View Article and Find Full Text PDFSea urchins (echinoids) are common model organisms for research in developmental biology and for their unusual transition from a bilaterally organized larva into a post-metamorphic adult with pentaradial body symmetry. The adult also has a calcareous endoskeleton with a multimetameric pattern of continuously added elements, among them the namesake of this phylum, spines. Nearly all echinoids have both large primary spines, and an associated set of smaller secondary spines.
View Article and Find Full Text PDFAnimals of the phylum Echinodermata are characterized by a pentaradially symmetric endoskeleton in adults. Echinoids also have endoskeletal spines ranging in length from several millimeters (sand dollars e.g.
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