Biocompatibility of cochlear implants

Ceramic, titanium and platinum guarantee a perfect bio-compatibility for cochlear implants. Moreover the long term efficacy of the electrode nerve interface is obtained thanks to a limited electric current density. Failure risks of implanted electronic are decreased by use of carefully selected components.     

A longitudinal study of the acquisition of language by two German-speaking children with cochlear implants and of their mothers' speech

The development of language in two children with cochlear implants was analyzed using longitudinal data of videorecorded mother-child interactions. Recordings were made over a period of 14 months for child A and over a period of 3 years for child B. At the beginning of data collection the children were 2;11 and 3;7 respectively. Results reveal substantial differences between the two children and their mothers. Child B was slow in acquiring grammar, with vocalizations and non-linguistic communicative behavior persisting. The child also used language in a labeling function. Child B's MLU (mean length of utterance) never exceeded 2.7 morphemes and his syntax remained rudimentary. Child A had a highly imitative style at the beginning, but then progressed to the spontaneous use of multi-word utterances very quickly, reaching an MLU of 5.6 morphemes in less than 2 years. Child A progressed to correct morphology and a fairly complex syntax. The children's mothers differed with respect to their use of exaggerated intonation patterns, repetitions and expansions, the use of labeling, questions, and directives. Results are discussed in terms of the influence of children's information processing styles and mothers' speech input.     

Asynchronous sequential stimulation. A new signal treatment for cochlear implants

Cochlear implants use a fixed or FO dependent stimulation rate, whatever the sound analysed (vowel or consonant) and its analysis procedure (fixed filters or FFT). We present a procedure which varies as a function of the nature of the input signal. This method is based on FFT analysis using a variable with analysis window. Short windows are applied on the transient part of the signal, providing poor frequency resolution but good time resolution; they accurately permit to follow the speech signal in time during its fast temporal variations. Large windows are applied on the stationary parts of the signal, providing better frequency resolution, but poor time resolution. Transient parts of the speech order this window switching; they are detected using the statistical properties of the FFT; moreover the narrow windowing is coupled with an increase of the stimulation frequency. This strategy has been implemented using the Digisonic cochlear implant software, and clinically assessed on 6 regular cochlear implant users, owing to a consonant-vowel-consonant test. This Asynchronous-Interleaved-Stimulation (AIS) strategy provides the patients with better discrimination than fixed window FFT analysis. The coding protocol are described and results presented.     

A preliminary study of the effects of crash helmet visor color on color recognition.

Asked 60 Ss to report whether a series of slide presentations contained red, yellow, green, or none of these colors. Ss viewed the slides through either a colored crash helmet visor or a clear helmet visor. Visor colors used were blue, green, orange, smoke, and yellow. Colored visors increased the number of color recognition errors, and restricted use of colored visors is advised. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

调职法律问题初探

近年来,我国用人单位与劳动者之间的调职争议频发,但有关调职的立法与研究却相对匮乏.结合具体案例,对调职的类型与法律性质进行分析是深入研究调职法律制度的前提.在此基础上对我国现有的调职立法进行评析,从而有利于更加公正、合理地解决调职法律问题.     

A biomechanical study of flexible penile implants

The prostheses used are silicone elastomer flexible penile implants. They are not hard, but flexible and capable of being elongated without traction. These implants have the advantage of resisting axial pressure which facilitates intromission, even in the absence of erection. Their flexibility also allows the penis to hang when the patient is standing. For the penis to hang normally, it must be sufficiently long (hence the value of cavernopubic release) and the intracavernous cavity must be longer than the prosthesis. The prosthesis does not alter the cavernous artery, but markedly flattens the venous plexus (lakes and efferent veins).     

Factors affecting auditory performance of postlinguistically deaf adults using cochlear implants

A model of auditory performance and a model of ganglion cell survival in postlinguistically deafened adult cochlear implant users are suggested to describe the effects of aetiology, duration of deafness, age at implantation, age at onset of deafness, and duration of implant use. The models were compared with published data and a composite data set including 808 implant users. Qualitative agreement with the model of auditory performance was found. Duration of deafness had a strong negative effect on performance. Age at implantation had a slight negative effect on performance, increasing after age 60 years. Age at onset of deafness had little effect on performance up to age 60. Duration of implant use had a positive effect on performance. Aetiology had a relatively weak effect on performance.     

Spatial resolution of cochlear implants: the electrical field and excitation of auditory afferents

This paper investigates the spatial resolution of electrical intracochlear stimulation in order to enable further refinement of cochlear implants. For this purpose electrical potential distributions around a conventional human intracochlear electrode (NUCLEUS-22) were measured in a tank, in cat cadaver cochleae and in living cat cochleae. Potential gradients were calculated where of importance. The values were compared to spatial tuning curves from cat primary auditory afferents in electrical mono-, bi-, and various tripolar stimulation modes. Finally, a lumped element model was developed to elucidate the single fiber data. Tank potential measurements show the principal features of the different stimulation modes but are not sufficient to explain all the features of experimental data from single fibers. Intracochlear potential measurements indicate an increase in spatial resolution in an apical direction. The single fiber data also confirm that a tripolar stimulus configuration provides significantly better spatial resolution than any other stimulation mode presently in use.     

A preliminary study on correcting the high fold of the upper eyelid

Tests for the presence of Chlamydia trachomatis were performed in 432 children, aged 4 months to 16 years at the Department of Paediatric Nephrology of the Academy of Wroc?aw, Poland. The children were hospitalised because of recurrent urinary tract infection. The presence of Chlamydia trachomatis was established in 27.5% of children by tissue culture on McCoy cells, in 22.8% when using the Chlamyset test (Orion Diagnostica) and in 8.9% when using the Chlamydiazyme test (Abbott).     

活性炭吸附金的初步研究

本文介绍美国研究活性炭从矿浆中吸附金的方法和设备,以及我们采用该方法所取得的研究成果。其中包括活性炭的种类及其用量的确定;金的吸附速率和金的平衡吸附曲线;以及炭浆法和炭浸法的比较。     

Lodestones, quackery, and science: electrical stimulation of the ear before cochlear implants

1. In whole-cell patch recording, the relative potency of the blocking action of sematilide on IK1 was found to be constant at each potential level of IK1 activation. Under more acidic condition, the degree of block was decreased. These results strongly suggested that the neutral form of sematilide may penetrate the cardiac cell membrane via hydrophobic pathway. 2. In cell-attached patches, sematilide prolonged the interburst interval and reduced the opening probabilities of the IK1 channel without affecting either the mean open time or the mean closed time within a burst.     

A preliminary study on dressing patterns and incidence of candidiasis

The incidence of candidiasis in two groups of voluntary participants wearing tight and loose fitted dresses was investigated by both microscopic and cultural techniques for a period of two months. Two-thirds of the positives by stain and culture were recovered from those wearing tight clothing (P < 0.05). The findings suggest that tight clothing can predispose the wearer to candidiasis, an organism that can cause vaginitis. (Am J Public Health 1982; 72:176-177.)     

Further experience with a straight, vertical incision for placement of cochlear implants

Experience with a straight, vertical incision for cochlear implantation in 168 patients of all ages is reported and comparison made with previous experience using a 'C' shaped incision in 173 patients with regard to complications encountered. With the straight incision the only complication was a wound infection which settled in one week; this is in contrast to the 'C' shaped incision, which was associated with a number of serious complications. The straight incision also compared favourably with the other incisions commonly used for cochlear implantation and appears to offer advantages over them.     

Clarion cochlear implant: short-term effects on voice parameters

The effect of acetylcholine on the neurointermediate lobe beta-endorphin secretion was studied in the neonatal and in the adult rat in vitro. Acetylcholine stimulated beta-endorphin secretion from the 2-day- and 5-day-old neurointermediate lobe, the effect was dose dependent and more pronounced in the presence of the cholinesterase inhibitor eserine. The 10-day-, the 21-day-old and the adult rat neurointermediate lobes did not respond to acetylcholine, even in the presence of eserine. Basal beta-endorphin secretion was elevated by the D2 receptor antagonist sulpiride, but acetylcholine was without effect in the 10-day-old and in the adult neurointermediate lobe even after dopamine receptor blockade. The beta-endorphin stimulatory response to acetylcholine was diminished by the M1 muscarinic receptor antagonist pirenzepine and blocked by the M3 > M1 antagonist 4-diamino-phenyl-piperidine (4-DAMP). The selective M2 antagonist methoctramine and nicotine had no effect. These data indicate that the neurointermediate lobe beta-endorphin secretion is under special muscarinic cholinergic regulation for a relatively short time after birth. The disappearance of this stimulatory cholinergic effect in later life might be due to changes in the intracellular secretory machinery in the IL and/or to the uncoupling of the cholinergic receptors from the intracellular signal transduction system(s) responsible for the stimulated secretion in the rat melanotrope cells.     

Everyday problems and stress faced by parents of children with cochlear implants.

Objectives: To explore everyday problems associated with parenting children who undergo cochlear implantation (CI), to investigate parents' interpersonal relationships as a resource for collaborative problem solving, and to examine links among parents' everyday problems, stress, and life satisfaction. Method: 31 parents of deaf children with CI responded to open-ended questions regarding types of everyday problems encountered within the specific context of parenting those children. Parents also completed the Parental Stress Index/Short Form and the Life Satisfaction Scale. Results: Problems were categorized in 9 domains: implant drawbacks, communication difficulties, child's behavior and character, socialization, habilitation demands and parenting role, financial difficulties, services, educating others and/or advocacy, and academic concerns. Professionals, spouses, and other parents of deaf children were frequently nominated partners for collaborative everyday problem solving and coping. Significant correlations emerged among parents' everyday problems, stress, and life satisfaction. Conclusions: Findings enhance understanding regarding the contextual specificity of everyday problems associated with raising deaf children with CI, beyond that obtained from a general measure of parental stress. This, in turn, can guide habilitation teams in working with families of implanted children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychological and emotional effects of the use of oral baclofen: a preliminary study

Spasticity is a common problem following spinal cord injury. The drug of choice to control spasms is baclofen. There would appear to be no reported studies which have evaluated the psychological and emotional effect of this drug. This preliminary study investigated a number of such effects, including depression, anxiety and general mood state. First, we examined 10 subjects before and during the administration of baclofen. They were then compared to a control group of 12 subjects. A second cohort of 12 subjects taking baclofen were compared to a control group of nine subjects at a specific time after injury. Results indicated that whilst some significant differences were found, suggesting an increase in fatigue with use of baclofen, no major adverse psychological effects were noted. The implications of these results were discussed and suggestions for further research were highlighted.     

Positron emission tomography of auditory sensation in deaf patients and patients with cochlear implants

The present study investigated the function of the auditory cortices in severely hearing-impaired or deaf patients and cochlear implant patients before and after auditory stimulation. Positron emission computed tomography (PET), which can detect brain activity by providing quantitative measurements of the metabolic rates of oxygen and glucose, was used. In patients with residual hearing, the activity of the auditory cortex measured by PET was almost normal. Among the totally deaf patients, the longer the duration of deafness, the lower the brain activity in the auditory cortex measured by PET. Patients who had been deaf for a long period showed remarkably reduced metabolic rates in the auditory cortices. However, following implantation of the cochlear device, the metabolic activity returned to near-normal levels. These findings suggest that activation of the speech comprehension mechanism of the higher brain system can be initiated by sound signals from the implant devices.