title: Morphology of human sweat ducts observed by optical coherence tomography and their frequency of resonance in the terahertz frequency region.
abstract: It is crucial to understand the various biological effects induced by terahertz (THz) electromagnetic waves with the rapid development of electronic and photonic devices operating in the THz frequency region. The presence of sweat glands plays an important role in THz wave interactions with human skin. We investigated the morphological features of sweat ducts using optical coherence tomography (OCT) to further understand such phenomena. We observed remarkable features of the ducts, such as their clear helical structure. The intersubject and intrasubject variations in the diameter of sweat ducts were considerably smaller than the variations in other structural parameters, such as length and number of turns. Based on the sweat duct dimensions and THz dielectric properties of skin measured using terahertz time-domain spectroscopy (THz-TDS), we calculated the resonating frequency of the sweat duct under the assumption of it functioning as a helical antenna. Here, we show that the resonance frequency in the axial mode of operation lies in the THz wave region with a centre frequency of 0.44 ± 0.07 THz. We expect that these findings will further our understanding of the various health consequences of the interaction of THz waves with human beings.
authors.affiliation: Nagoya University, Furo-cho, Chikusa Ku, Nagoya 464-8603, Japan.
authors.forename: Saroj R
authors.initials: SR
authors.lastname: Tripathi
authors.affiliation: Nagoya University, Furo-cho, Chikusa Ku, Nagoya 464-8603, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Miyata
authors.affiliation: The Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel.
authors.forename: Paul Ben
authors.initials: PB
authors.lastname: Ishai
authors.affiliation: 1] Nagoya University, Furo-cho, Chikusa Ku, Nagoya 464-8603, Japan [2] RIKEN, 519-1399 Aramakiaoba, Aoba, Sendai 980-0845, Japan.
authors.forename: Kodo
authors.initials: K
authors.lastname: Kawase
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D012867:Skin; D013545:Sweat Glands; D055069:Terahertz Imaging; D041623:Tomography, Optical Coherence