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M. C. Hastings - One of the best experts on this subject based on the ideXlab platform.
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A mathematical analysis of the peripheral auditory system mechanics in the goldfish (Carassius auratus)
Journal of the Acoustical Society of America, 2000Co-Authors: James J. Finneran, M. C. HastingsAbstract:The dynamic response of the goldfish peripheral auditory system has been analyzed using lumped-parameter mechanical and fluid system models for the swimbladder, Weberian apparatus, and saccule. The swimbladder is treated as a two degree-of-freedom mechanical system consisting of two coupled mass-spring-damper arrangements. The swimbladder is coupled to the Weberian ossicles using a phenomenological analysis of the anterior swimbladder Tunica Externa which permits both stretching and sliding. Analysis of the saccule features only a single degree of freedom, corresponding to the direction of orientation of the ciliary bundles. Inputs to the saccule consist of the transverse canal fluid motion and the motion of the animal’s head (assumed to match the local acoustic particle motion). Mechanical properties required for the system equations were estimated from published literature, direct measurements, and curve fits to experimental data for the motions of the swimbladders. The results indicate that the Weberia...
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A mathematical analysis of the peripheral auditory system mechanics in the goldfish (Carassius auratus)
Journal of the Acoustical Society of America, 2000Co-Authors: James J. Finneran, M. C. HastingsAbstract:The dynamic response of the goldfish peripheral auditory system has been analyzed using lumped-parameter mechanical and fluid system models for the swimbladder, Weberian apparatus, and saccule. The swimbladder is treated as a two degree-of-freedom mechanical system consisting of two coupled mass-spring-damper arrangements. The swimbladder is coupled to the Weberian ossicles using a phenomenological analysis of the anterior swimbladder Tunica Externa which permits both stretching and sliding. Analysis of the saccule features only a single degree of freedom, corresponding to the direction of orientation of the ciliary bundles. Inputs to the saccule consist of the transverse canal fluid motion and the motion of the animal's head (assumed to match the local acoustic particle motion). Mechanical properties required for the system equations were estimated from published literature, direct measurements, and curve fits to experimental data for the motions of the swimbladders. The results indicate that the Weberian apparatus has a significant impact on hearing ability over the entire auditory bandwidth, not just at higher frequencies, and that the saccule functions as a displacement sensor above approximately 300 Hz.
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A cohesive lumped parameter analysis of the mechanics of the goldfish peripheral auditory system
Journal of the Acoustical Society of America, 1998Co-Authors: James J. Finneran, M. C. HastingsAbstract:A mathematical analysis has been formulated to model the dynamic behavior of the goldfish peripheral auditory system, including the swimbladders, Weberian apparatus, and saccule. The two‐chambered goldfish swimbladder is treated as a two degree‐of‐freedom mechanical system consisting of two coupled mass‐spring‐damper arrangements. The swimbladder is coupled to the Weberian ossicles using a phenomenological analysis of the anterior swimbladder Tunica Externa which permits both stretching and sliding. Analysis of the saccule features only a single degree‐of‐freedom, corresponding to the direction of orientation of the ciliary bundles. Inputs to the saccule consist of the transverse canal fluid motion and the motion of the animal’s head (assumed to match the local acoustic particle motion). Mechanical properties required for the system equations were estimated from published literature and direct measurements. Results of the analysis compare favorably to experimental data for the motions of the swimbladders ...
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Dynamic model of the goldfish peripheral auditory system
Journal of the Acoustical Society of America, 1995Co-Authors: James J. Finneran, M. C. HastingsAbstract:In this study, a dynamic, lumped parameter mathematical model was developed for the peripheral auditory system of the goldfish (Carassius auratus). This model expands upon and couples existing models for the swimbladder (anterior chamber) and saccular otolith by including the swimbladder Tunica interna and Tunica Externa, along with the Weberian apparatus. The viscoelastic properties of the Tunica Externa are based on data from Alexander [J. Exp. Biol. 38, 747–757 (1961)]. Model predictions correlate well with experimental data for swimbladder resonance frequency and damping and with audiograms obtained from behavioral conditioning experiments. Model results indicate that the Weberian apparatus has a major affect on auditory sensitivity throughout the audible frequency range of the goldfish. In addition, specific phase relationships between the Weberian, direct, and indirect contributions to saccular otolith motion are observed for changing source location. [Work supported by ONR Grant No. N00014‐94‐1‐0337.]
James J. Finneran - One of the best experts on this subject based on the ideXlab platform.
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A mathematical analysis of the peripheral auditory system mechanics in the goldfish (Carassius auratus)
Journal of the Acoustical Society of America, 2000Co-Authors: James J. Finneran, M. C. HastingsAbstract:The dynamic response of the goldfish peripheral auditory system has been analyzed using lumped-parameter mechanical and fluid system models for the swimbladder, Weberian apparatus, and saccule. The swimbladder is treated as a two degree-of-freedom mechanical system consisting of two coupled mass-spring-damper arrangements. The swimbladder is coupled to the Weberian ossicles using a phenomenological analysis of the anterior swimbladder Tunica Externa which permits both stretching and sliding. Analysis of the saccule features only a single degree of freedom, corresponding to the direction of orientation of the ciliary bundles. Inputs to the saccule consist of the transverse canal fluid motion and the motion of the animal’s head (assumed to match the local acoustic particle motion). Mechanical properties required for the system equations were estimated from published literature, direct measurements, and curve fits to experimental data for the motions of the swimbladders. The results indicate that the Weberia...
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A mathematical analysis of the peripheral auditory system mechanics in the goldfish (Carassius auratus)
Journal of the Acoustical Society of America, 2000Co-Authors: James J. Finneran, M. C. HastingsAbstract:The dynamic response of the goldfish peripheral auditory system has been analyzed using lumped-parameter mechanical and fluid system models for the swimbladder, Weberian apparatus, and saccule. The swimbladder is treated as a two degree-of-freedom mechanical system consisting of two coupled mass-spring-damper arrangements. The swimbladder is coupled to the Weberian ossicles using a phenomenological analysis of the anterior swimbladder Tunica Externa which permits both stretching and sliding. Analysis of the saccule features only a single degree of freedom, corresponding to the direction of orientation of the ciliary bundles. Inputs to the saccule consist of the transverse canal fluid motion and the motion of the animal's head (assumed to match the local acoustic particle motion). Mechanical properties required for the system equations were estimated from published literature, direct measurements, and curve fits to experimental data for the motions of the swimbladders. The results indicate that the Weberian apparatus has a significant impact on hearing ability over the entire auditory bandwidth, not just at higher frequencies, and that the saccule functions as a displacement sensor above approximately 300 Hz.
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A cohesive lumped parameter analysis of the mechanics of the goldfish peripheral auditory system
Journal of the Acoustical Society of America, 1998Co-Authors: James J. Finneran, M. C. HastingsAbstract:A mathematical analysis has been formulated to model the dynamic behavior of the goldfish peripheral auditory system, including the swimbladders, Weberian apparatus, and saccule. The two‐chambered goldfish swimbladder is treated as a two degree‐of‐freedom mechanical system consisting of two coupled mass‐spring‐damper arrangements. The swimbladder is coupled to the Weberian ossicles using a phenomenological analysis of the anterior swimbladder Tunica Externa which permits both stretching and sliding. Analysis of the saccule features only a single degree‐of‐freedom, corresponding to the direction of orientation of the ciliary bundles. Inputs to the saccule consist of the transverse canal fluid motion and the motion of the animal’s head (assumed to match the local acoustic particle motion). Mechanical properties required for the system equations were estimated from published literature and direct measurements. Results of the analysis compare favorably to experimental data for the motions of the swimbladders ...
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Dynamic model of the goldfish peripheral auditory system
Journal of the Acoustical Society of America, 1995Co-Authors: James J. Finneran, M. C. HastingsAbstract:In this study, a dynamic, lumped parameter mathematical model was developed for the peripheral auditory system of the goldfish (Carassius auratus). This model expands upon and couples existing models for the swimbladder (anterior chamber) and saccular otolith by including the swimbladder Tunica interna and Tunica Externa, along with the Weberian apparatus. The viscoelastic properties of the Tunica Externa are based on data from Alexander [J. Exp. Biol. 38, 747–757 (1961)]. Model predictions correlate well with experimental data for swimbladder resonance frequency and damping and with audiograms obtained from behavioral conditioning experiments. Model results indicate that the Weberian apparatus has a major affect on auditory sensitivity throughout the audible frequency range of the goldfish. In addition, specific phase relationships between the Weberian, direct, and indirect contributions to saccular otolith motion are observed for changing source location. [Work supported by ONR Grant No. N00014‐94‐1‐0337.]
Pascal Jungbluth - One of the best experts on this subject based on the ideXlab platform.
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Postoperative brachial artery entrapment associated with pediatric supracondylar fracture of the humerus: a case report
Journal of Medical Case Reports, 2017Co-Authors: David Latz, Jan Grassmann, Erik Schiffner, Sebastian Gehrmann, Mansur Duran, Joachim Windolf, Pascal JungbluthAbstract:Background Severely displaced supracondylar fractures of the humerus in children are frequently associated with complications including neurovascular injuries, non-union, or compartment syndrome. In the current literature, no report exists about postoperative brachial artery entrapment in combination with an inconspicuous preoperative neurovascular examination. Case presentation We present a case of a 6-year-old white boy with a pulseless radial and ulnar artery after open reduction and internal fixation of a severely displaced supracondylar fracture of his right humerus (Gartland type III) using four K-wires. Remarkably, the preoperative neurovascular examination was inconspicuous. Doppler ultrasound of his brachial artery revealed no pulse when his elbow was in flexion and a faint pulse when it was in full extension 10 hours postoperatively. Revision surgery was performed immediately. On intraoperative examination, a kinking of his brachial artery caused by an entrapment of the Tunica Externa in the reduced fracture was seen and the artery was released by microsurgical arteriolysis immediately. At the final follow-up examination, positive palpable pulse with good capillary filling and, according to Flynn’s criteria, an excellent recovery of elbow function was observed 3 months postoperatively. Conclusions This case demonstrates a rare complication of postoperative artery entrapment with inconspicuous preoperative neurovascular examination. It strongly emphasizes the need for a standardized postoperative neurovascular assessment with fully flexed as well as fully extended elbow.
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Postoperative brachial artery entrapment associated with pediatric supracondylar fracture of the humerus: a case report.
Journal of Medical Case Reports, 2017Co-Authors: David Latz, Jan Grassmann, Erik Schiffner, Sebastian Gehrmann, Mansur Duran, Joachim Windolf, Pascal JungbluthAbstract:Severely displaced supracondylar fractures of the humerus in children are frequently associated with complications including neurovascular injuries, non-union, or compartment syndrome. In the current literature, no report exists about postoperative brachial artery entrapment in combination with an inconspicuous preoperative neurovascular examination. We present a case of a 6-year-old white boy with a pulseless radial and ulnar artery after open reduction and internal fixation of a severely displaced supracondylar fracture of his right humerus (Gartland type III) using four K-wires. Remarkably, the preoperative neurovascular examination was inconspicuous. Doppler ultrasound of his brachial artery revealed no pulse when his elbow was in flexion and a faint pulse when it was in full extension 10 hours postoperatively. Revision surgery was performed immediately. On intraoperative examination, a kinking of his brachial artery caused by an entrapment of the Tunica Externa in the reduced fracture was seen and the artery was released by microsurgical arteriolysis immediately. At the final follow-up examination, positive palpable pulse with good capillary filling and, according to Flynn’s criteria, an excellent recovery of elbow function was observed 3 months postoperatively. This case demonstrates a rare complication of postoperative artery entrapment with inconspicuous preoperative neurovascular examination. It strongly emphasizes the need for a standardized postoperative neurovascular assessment with fully flexed as well as fully extended elbow.
David Latz - One of the best experts on this subject based on the ideXlab platform.
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Postoperative brachial artery entrapment associated with pediatric supracondylar fracture of the humerus: a case report
Journal of Medical Case Reports, 2017Co-Authors: David Latz, Jan Grassmann, Erik Schiffner, Sebastian Gehrmann, Mansur Duran, Joachim Windolf, Pascal JungbluthAbstract:Background Severely displaced supracondylar fractures of the humerus in children are frequently associated with complications including neurovascular injuries, non-union, or compartment syndrome. In the current literature, no report exists about postoperative brachial artery entrapment in combination with an inconspicuous preoperative neurovascular examination. Case presentation We present a case of a 6-year-old white boy with a pulseless radial and ulnar artery after open reduction and internal fixation of a severely displaced supracondylar fracture of his right humerus (Gartland type III) using four K-wires. Remarkably, the preoperative neurovascular examination was inconspicuous. Doppler ultrasound of his brachial artery revealed no pulse when his elbow was in flexion and a faint pulse when it was in full extension 10 hours postoperatively. Revision surgery was performed immediately. On intraoperative examination, a kinking of his brachial artery caused by an entrapment of the Tunica Externa in the reduced fracture was seen and the artery was released by microsurgical arteriolysis immediately. At the final follow-up examination, positive palpable pulse with good capillary filling and, according to Flynn’s criteria, an excellent recovery of elbow function was observed 3 months postoperatively. Conclusions This case demonstrates a rare complication of postoperative artery entrapment with inconspicuous preoperative neurovascular examination. It strongly emphasizes the need for a standardized postoperative neurovascular assessment with fully flexed as well as fully extended elbow.
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Postoperative brachial artery entrapment associated with pediatric supracondylar fracture of the humerus: a case report.
Journal of Medical Case Reports, 2017Co-Authors: David Latz, Jan Grassmann, Erik Schiffner, Sebastian Gehrmann, Mansur Duran, Joachim Windolf, Pascal JungbluthAbstract:Severely displaced supracondylar fractures of the humerus in children are frequently associated with complications including neurovascular injuries, non-union, or compartment syndrome. In the current literature, no report exists about postoperative brachial artery entrapment in combination with an inconspicuous preoperative neurovascular examination. We present a case of a 6-year-old white boy with a pulseless radial and ulnar artery after open reduction and internal fixation of a severely displaced supracondylar fracture of his right humerus (Gartland type III) using four K-wires. Remarkably, the preoperative neurovascular examination was inconspicuous. Doppler ultrasound of his brachial artery revealed no pulse when his elbow was in flexion and a faint pulse when it was in full extension 10 hours postoperatively. Revision surgery was performed immediately. On intraoperative examination, a kinking of his brachial artery caused by an entrapment of the Tunica Externa in the reduced fracture was seen and the artery was released by microsurgical arteriolysis immediately. At the final follow-up examination, positive palpable pulse with good capillary filling and, according to Flynn’s criteria, an excellent recovery of elbow function was observed 3 months postoperatively. This case demonstrates a rare complication of postoperative artery entrapment with inconspicuous preoperative neurovascular examination. It strongly emphasizes the need for a standardized postoperative neurovascular assessment with fully flexed as well as fully extended elbow.
Gao Lian-ru - One of the best experts on this subject based on the ideXlab platform.
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Isolation and identification of mesenchymal stem cells from human umbilical cord Wharton's Jelly
China Journal of Modern Medicine, 2020Co-Authors: Gao Lian-ruAbstract:【Objectives】To explore methods for isolation of mesenchymal stem cells derived from human umbilical cord wharton's jelly and to identify the isolated cells which are able to differentiate into osteogenic and adipogenic tissues.【Methods】After removal of umbilical arteries,vein and Tunica Externa of umbilical cord,the remaining tissue was wharton's jelly.To obtain adherent cells,wharton's jelly of umbilical cord was cut into pieces and digested with 0.2% collagenase of type Ⅱ.The mesenchymal stem cells of umbilical cord were passaged.Phenotypes were detected with flow cytometry with surface antigens CD44,CD90,CD105,CD73,CD34,CD45,HLA-DR,HLA-ABC and osteogenic and adipogenic tissues were identified by differentiation.【Results】Wharton's jelly of human umbilical cord had abundant stem cells.The isolation of these cells had been proved easily when collagenase was used to detach the cells from Wharton's jelly.Flow cytometry analyses revealed that the stem cells from Wharton's jelly represented a nonhematopoietic cell popution.However they expressed amounts of MSCs markers,such as CD44,CD90,CD105,CD73,meanwhile positive expression of HLA-ABC was found in the stem cells,but not CD34,CD45,HLA-DR.Immunohistochemistry showed that the MSCs strongly expressed alkaline phosphatase and Von Kossa positive.【Conclusions】Mesenchymal stem cells can be successfully isolated from human umbilical cord Wharton's jelly.The stem cells derived from Wharton's jelly of human umbilical cord may be a novel alternative source of human MSCs for experimental and clinical applications.
