Previous analysis on the lateral stability of hovering insects, which reported a destabilizing roll moment due to a lateral gust, has relied on the results of a single wing without considering a presence of the contralateral wing (wing-wing interaction). Here, we investigated the presence of the contralateral wing on the aerodynamic and flight dynamic characteristics of a hovering hawkmoth under a lateral gust. By employing a dynamically scaled-up mechanical model and a servo-driven towing system installed in a water tank, we found that the presence of the contralateral wing plays a significant role in the lateral static stability. The contralateral wing mitigated an excessive aerodynamic force on the wing at the leeward side, thereby providing a negative roll moment to the body. Digital particle image velocimetry revealed an attenuated vortical system of the leading-edge vortex. An excessive effective angle of attack in the single wing case, which was caused by the root vortex of previous half stroke, was reduced by a downwash of the contralateral wing. The contralateral wing also relocated a neutral point in close proximity to the wing hinge points above the actual center of gravity, providing a practical static margin to a hovering hawkmoth.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6874597 | PMC |
http://dx.doi.org/10.1038/s41598-019-53625-0 | DOI Listing |
Clin Oral Investig
December 2024
Department of Prosthetic Dentistry, Medical Faculty, Heidelberg University, Heidelberg, Germany.
Objectives: To prospectively evaluate the wear of posterior zirconia resin-bonded fixed partial dentures (RBFPDs) with polished occlusal surfaces and their natural enamel antagonists compared to contralateral controls in an enamel-enamel contact over 5 years.
Materials And Methods: In six patients with either an inlay- or wing-retained RBFPD made of monolithic 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP), wear was evaluated indirectly using baseline and annual polyvinyl siloxane impressions. Resulting gypsum models were digitized and aligned by unchanged surface areas.
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
November 2024
ENT institute and Department of Otolaryngology, Eye & ENT Hospital, Fudan University, Shanghai200031, China Research Units of New Technologies of Endoscopic Surgery in Skull Base Tumor, Shanghai200031, China.
To investigate the distribution and primary drainage sites of the venous drainage system in the pedicled nasal septal mucosal flap, as well as to examine protective measures for the venous system of the nasal septal mucosal flap and its application in repairing the nasal skull base through the anatomical study of the nasal septum mucosal venous system in cadavers. Gross anatomy dissections were performed on 13 sides perfused fresh frozen cadaveric head specimens. The nasal septum mucosal flap was separated along the perichondrium and subperiosteum, then passed across the vomer, anterior wall of sphenoid sinus, clivus, and towards the anterior edge of vertical plate of palatine bone.
View Article and Find Full Text PDFEur Arch Otorhinolaryngol
January 2025
School of Biomedical Engineering and Imaging Sciences, King's College London, London, UK.
Purpose: To compare the calibre of the cochlear (CN), superior vestibular (SVN) and inferior vestibular (IVN) nerves on magnetic resonance imaging (MRI), both between Ménière's Disease (MD) ears and clinical controls, and between inner ears with and without endolymphatic hydrops (EH) on MRI.
Methods: A retrospective case-control study evaluated patients undergoing MRI for suspected hydropic ear disease from 9/2017 to 8/2022. The CN, SVN, IVN and facial nerve (FN) diameters and cross-sectional areas (CSA) were measured on T2-weighted sequences whilst EH was evaluated on delayed post-gadolinium MRI.
Neurosurg Rev
July 2024
Department of Neurological Surgery, Pauline Braathen Neurological Center, Cleveland Clinic Florida, Weston, FL, USA.
Purpose: The past two decades have witnessed the rise of keyhole microscopic minimally invasive surgeries, including the transciliary supraorbital approach (TCA) and transpalpebral approach (TPA), commonly known as the transorbital approach. This study aims to elucidate the nuances, specific indications, and advantages of each approach.
Methods: A series of dissections were conducted on five formalin-fixed, alcohol-preserved cadaver heads.
Neurosurg Focus
April 2024
Departments of1Neurological Surgery and.
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