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1.
Article in English | MEDLINE | ID: mdl-29994363

ABSTRACT

We present the results of a Local Lorentz Invariance (LLI) test performed with the 133Cs cold atom clock FO2 [1], hosted at SYRTE. Such test, relating the frequency shift between 133Cs hyperfine Zeeman substates to the Lorentz violating coefficients of the Standard Model Extension (SME), has already been realized in [2] and led to state-of-the-art constraints on several SME proton coefficients. In this second analysis we used an improved model, based on a second order Lorentz transformation and a SCRMF nuclear model, which enables us to extend the scope of the analysis from purely proton to both proton and neutron coefficients. We have also become sensitive to the isotropic coefficient ~cTT, another SME coefficient that was not constrained in [2]. The resulting limits on SME coefficients improve by up to 13 orders of magnitude the present maximal sensitivities for laboratory tests and reach the generally expected suppression scales at which signatures of Lorentz violation could appear [3].

2.
Article in English | MEDLINE | ID: mdl-29856711

ABSTRACT

We present the results of a local Lorentz invariance (LLI) test performed with the 133Cs cold atom clock FO2, hosted at SYRTE. Such a test, relating the frequency shift between 133Cs hyperfine Zeeman substates with the Lorentz violating coefficients of the standard model extension (SME), has already been realized by Wolf et al. and led to state-of-the-art constraints on several SME proton coefficients. In this second analysis, we used an improved model, based on a second-order Lorentz transformation and a self-consistent relativistic mean field nuclear model, which enables us to extend the scope of the analysis from purely proton to both proton and neutron coefficients. We have also become sensitive to the isotropic coefficient , another SME coefficient that was not constrained by Wolf et al. The resulting limits on SME coefficients improve by up to 13 orders of magnitude the present maximal sensitivities for laboratory tests and reach the generally expected suppression scales at which signatures of Lorentz violation could appear.

3.
J Laryngol Otol ; 100(4): 467-70, 1986 Apr.
Article in English | MEDLINE | ID: mdl-3958594

ABSTRACT

A 56-year-old woman presented with unilateral tinnitus and hearing loss for 18 months. A middle ear mass was detected clinically. At operation, the tumour was found to have eroded the stapes. The light and electron microscopic features of the tumour were those of a middle ear adenoma. This rare benign tumour has an excellent prognosis. Erosion of an ossicle has not been previously associated with this tumour. Benign adenomatous tumours arising from middle ear mucosa are rare (Mills and Fechner, 1984). The term adenoma of middle ear was proposed by Hyams and Michaels (1976), and their review of 20 cases emphasized the benign behaviour of these tumours. We report a case of middle ear adenoma in which ossicular erosion occurred.


Subject(s)
Adenoma/ultrastructure , Ear Neoplasms/ultrastructure , Ear, Middle/ultrastructure , Female , Humans , Microscopy, Electron , Middle Aged
4.
Aust N Z J Surg ; 54(6): 519-26, 1984 Dec.
Article in English | MEDLINE | ID: mdl-6393936

ABSTRACT

The clinical trial of a multi-channel cochlear prosthesis has been carried out on 10 profoundly-totally deaf adult patients. Speech perception tests have shown that all the patients received significant benefit from the device. They obtained improvements in understanding running speech from 47% to 550% when using the device in conjunction with lipreading compared to lipreading alone. With an open-set CID sentence test, three patients obtained scores showing an ability to understand speech without the need to lipread, and a further three patients had scores indicating they could also receive useful information without lipreading. In two patients, very limited open-set scores for electrical stimulation alone were obtained. This was most probably due to the fact that only a few channels of stimulation were possible due to cochlear disease, and they were therefore receiving information more like a single-channel device. The prosthesis has also been found to provide considerable help in hearing and recognizing everyday sounds.


Subject(s)
Cochlear Implants/instrumentation , Deafness/therapy , Adult , Aged , Clinical Trials as Topic , Female , Humans , Male , Middle Aged , Speech Discrimination Tests , Speech Perception
5.
Ann Otol Rhinol Laryngol ; 93(3 Pt 1): 204-7, 1984.
Article in English | MEDLINE | ID: mdl-6547284

ABSTRACT

An improved multiple-channel cochlear implant has been developed. The titanium container with enclosed electronics, the receiver coil, and the connector are embedded in medical-grade Silastic. The upper half of the implant has a diameter of 35 mm and a height of 4.5 mm, and the lower half a diameter of 23 mm and a height of 5 mm. The electrode array has also been designed to reduce the possibility of breakage due to repeated movements over many years. The surgery involves drilling a bed in the mastoid bone for the receiver-stimulator, and fixing the proximal electrode under the mastoid cortex. Gentle insertion of the electrode array through the round window and along the scala tympani is achieved with a specially designed microclaw .


Subject(s)
Cochlear Implants , Deafness/rehabilitation , Electrodes, Implanted , Equipment Design , Equipment Failure , Humans , Methods , Otolaryngology/instrumentation , Postoperative Period , Surgical Instruments
6.
Med J Aust ; 2(9): 430-3, 1983 Oct 29.
Article in English | MEDLINE | ID: mdl-6355794

ABSTRACT

The clinical trial of a multiple-channel cochlear prosthesis was undertaken in four patients with postlingual deafness and profound total hearing loss. The results of open-set speech tests confirmed that, using electrical stimulation alone, one patient could have a meaningful conversation without resorting to lipreading (for example, this patient uses the prosthesis to converse with her husband on the telephone). The results of closed-set speech tests also suggested that a multiple-channel stimulator is more effective than a single-channel one in conveying speech information. The cochlear prosthesis was especially effective in all four patients when it was used in conjunction with lipreading, and speech-tracking tests showed that the patients could combine the information obtained from both electrical stimulation and lipreading.


Subject(s)
Cochlear Implants , Deafness/rehabilitation , Adult , Clinical Trials as Topic , Electric Stimulation , Female , Humans , Male , Middle Aged
9.
J Laryngol Otol ; 93(7): 735-6, 1979 Jul.
Article in English | MEDLINE | ID: mdl-469402
11.
J Laryngol Otol ; 93(2): 107-9, 1979 Feb.
Article in English | MEDLINE | ID: mdl-429893

ABSTRACT

This multiple-electrode array for round window cochlear implantation is a robust, reliable system for inserting 20 mm along the scala tympani with a minimum of trauma and can provide for bipolar stimulation.


Subject(s)
Cochlea , Electrodes, Implanted , Electronics, Medical/instrumentation , Round Window, Ear , Deafness/therapy , Electric Stimulation/instrumentation , Humans
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