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Objective: To report a reliable method in obtaining optimal cochlear basal turn and cross-section (c/s) of internal auditory canal (IAC) supporting Cochlear implantation (CI) procedure., Materials and Methods: Computer tomography (CT) and magnetic resonance image (MRI) scans of potential CI candidates from 2018 to 2022 from the tertiary center were considered for analysis. Slicer software was used in three-dimensional (3D) segmentation of inner ear and for capturing the cochlear basal turn., Results: A total of 1932 head scans were made available for the analysis and out of which 1866 scans had normal anatomy (NA) inner ear. Incomplete partition (IP) type-I was identified in 19 ears, IP type-II in 27 ears, IP type-III in 6 ears, cochlear hypoplasia (CH) type-I in 6 ears, CH type-II in 1 ear, CH type-III in 3 ears, and CH type-IV is 3 ears, and enlarged vestibular aqueduct syndrome in 1 ear. 3D segmented inner ear helped in successfully obtaining the cochlear basal turn and the c/s of IAC in all anatomical types. Time taken to capture the cochlear basal turn with the help of 3D segmented inner ear was <1 min. Within the NA category, five cases showed scalar ossification, and its extent was identified in the cochlear basal turn., Conclusion: The identification and the extent of ossification in the scala tympani, shape of the basal turn, and the cochlear size measurement in cochlear basal turn has high clinical relevance as this helps in surgical planning and in choosing appropriate electrode length. Level of evidence: Level 2 to the best of our understanding., Competing Interests: Andras Kedves and Anandhan Dhanasingh are full‐time employees of a hearing implant organization (MED‐EL) within research and development department with no marketing activities. All the other authors declare no conflict of interest and this study was performed truly for educational purpose., (© 2023 The Authors. Laryngoscope Investigative Otolaryngology published by Wiley Periodicals LLC on behalf of The Triological Society.)

Cochlear implantation (CI) is currently the recognized and most promising method of rehabilitation of patients suffering from profound hearing loss and deafness. During the surgical stage of CI, one of the most unpleasant intraoperative features is CSF leakage from the cochlea opening. Most often it occurs in patients with malformations of the inner ear, with temporal bone fractures and with cochlear otosclerosis. The difficulty of choosing the tactics of surgical intervention in these patients is caused by the large variability of the anatomical structures of the inner ear. In the period from 2017 to 2021, 1954 patients underwent CI, of which 83 were patients with cochlea malformations (65 intraoperative CSF leakages), 14 with the temporal bones fractures (2 intraoperative CSF leakage), 12 with cochlear otosclerosis (1 CSF leakage), while 3 spontaneous intraoperative CSF leakages were noted in patients with normal cochlea anatomy and hyperpnumotized temporal bone pyramid and enlarged vestibular aqueduct. The highest risk of intraoperative CSF leakage was observed in patients with inner ear malformations (common cavity - 10, incomplete partition type III - 15) and anomalies of the internal auditory canal - 5 (dilated IAC - more than 8.5 mm in diameter). Moderate risk of intraoperative CSF leakage was typical for patients with incomplete partition type I (15 patients) and type II (25 patients).

Auditory nerve dysplasia (AND) can encompass various conditions of the auditory nerve (AN), ranging from true aplasia to hypoplasia. The purpose of this review is to discuss the prospect of cochlear implantation (CI) and subsequent auditory speech rehabilitation for AN abnormality. Studies of different authors when working with this category of children, possible results and methods of diagnostics of the AN condition are presented.

Background and Objective: The cochlear implant (CI) electrode insertion process is a key step in CI surgery. One of the aims of advances in robotic-assisted CI surgery (RACIS) is to realize better cochlear structure preservation and to precisely control insertion. The aim of this literature review is to gain insight into electrode selection for RACIS by acquiring a thorough knowledge of electrode insertion and related complications from classic CI surgery involving a manual electrode insertion process., Methods: A systematic electronic search of the literature was carried out using PubMed, Scopus, Cochrane, and Web of Science to find relevant literature on electrode tip fold over (ETFO), electrode scalar deviation (ESD), and electrode migration (EM) from both pre-shaped and straight electrode types., Results: A total of 82 studies that include 8,603 ears implanted with a CI, i.e., pre-shaped (4,869) and straight electrodes (3,734), were evaluated. The rate of ETFO (25 studies, 2,335 ears), ESD (39 studies, 3,073 ears), and EM (18 studies, 3,195 ears) was determined. An incidence rate (±95% CI) of 5.38% (4.4-6.6%) of ETFO, 28.6% (26.6-30.6%) of ESD, and 0.53% (0.2-1.1%) of EM is associated with pre-shaped electrodes, whereas with straight electrodes it was 0.51% (0.1-1.3%), 11% (9.2-13.0%), and 3.2% (2.5-3.95%), respectively. The differences between the pre-shaped and straight electrode types are highly significant ( p < 0.001). Laboratory experiments show evidence that robotic insertions of electrodes are less traumatic than manual insertions. The influence of round window (RW) vs. cochleostomy (Coch) was not assessed., Conclusion: Considering the current electrode designs available and the reported incidence of insertion complications, the use of straight electrodes in RACIS and conventional CI surgery (and manual insertion) appears to be less traumatic to intracochlear structures compared with pre-shaped electrodes. However, EM of straight electrodes should be anticipated. RACIS has the potential to reduce these complications., Competing Interests: MK is the chief surgeon and Director of Madras ENT Research Foundation Pvt. LTD., which is the organization he founded and for which he is currently working for. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Van de Heyning, Roland, Lassaletta, Agrawal, Atlas, Baumgartner, Brown, Caversaccio, Dazert, Gstoettner, Hagen, Hagr, Jablonski, Kameswaran, Kuzovkov, Leinung, Li, Loth, Magele, Mlynski, Mueller, Parnes, Radeloff, Raine, Rajan, Schmutzhard, Skarzynski, Skarzynski, Sprinzl, Staecker, Stöver, Tavora-Viera, Topsakal, Usami, Van Rompaey, Weiss, Wimmer, Zernotti and Gavilan.)

Cognitive function is a complex brain function that is important in the cognition of the reality and connecting with it. It has a complicated reflex basis, arises from external factors exposure, improves by growing up and learning till its maximum and declines in the elderly age. For several years it was believed that cognitive function drop is connected with ageing processes of the whole organism. However, the results of the latest studies show that it can be affected by many factors. Two of the most influencing factors are hearing and vestibular efficiency. Moreover, hearing and vestibular normalization can even improve the cognitive function. Unfortunately, studies, that describe the role of hearing and vestibular function in the cognitive sphere, are extremely rare. That is why further research is very important, especially in the rehabilitation tactics. For elderly patients with severe-to-profound hearing loss cochlear implantation is the optimal rehabilitation method. However, ear surgery can lead to such complication as vestibular dysfunction. That is why preoperative diagnostics and postoperative care are very important for preventing cognitive impairments.

Purpose: Magnetic resonance imaging (MRI) is often used to visualize and diagnose soft tissues. Hearing implant (HI) recipients are likely to require at least one MRI scan during their lifetime. However, the MRI scanner can interact with the implant magnet, resulting in complications for the HI recipient. This survey, which was conducted in two phases, aimed to evaluate the safety and performance of MRI scans for individuals with a HI manufactured by MED-EL (MED-EL GmbH, Innsbruck, Austria)., Methods: A survey was developed and distributed in two phases to HEARRING clinics to obtain information about the use of MRI for recipients of MED-EL devices. Phase 1 focused on how often MRI is used in diagnostic imaging of the head region of the cochlear implant (CI) recipients. Phase 2 collected safety information about MRI scans performed on HI recipients., Results: 106 of the 126 MRI scans reported in this survey were performed at a field strength of 1.5 T, on HI recipients who wore the SYNCHRONY CI or SYNCHRONY ABI. The head and spine were the most frequently imaged regions. 123 of the 126 scans were performed without any complications; two HI recipients experienced discomfort/pain. One recipient required reimplantation after an MRI was performed using a scanner that had not been approved for that implant. There was only one case that required surgical removal of the implant to reduce the imaging artefact., Conclusion: Individuals with either a SYNCHRONY CI or SYNCHRONY ABI from MED-EL can safely undergo a 1.5 T MRI when it is performed according to the manufacturer's safety policies and procedures., (© 2021. The Author(s).)

Due to unique optical/mechanical properties and significant resistance to harsh radiation environments, corundum (α-Al 2 O 3 ) is considered as a promising candidate material for windows and diagnostics in forthcoming fusion reactors. However, its properties are affected by radiation-induced (predominantly, by fast neutrons) structural defects. In this paper, we analyze thermal stability and recombination kinetics of primary Frenkel defects in anion sublattice - the F-type electronic centers and complementary oxygen interstitials in fast-neutron-irradiated corundum single crystals. Combining precisely measured thermal annealing kinetics for four types of primary radiation defects (neutral and charged Frenkel pairs) and the advanced model of chemical reactions, we have demonstrated for the first time a co-existence of the two types of interstitial defects - neutral O atoms and negatively charged O - ions (with attributed optical absorption bands peaked at energies of 6.5 eV and 5.6 eV, respectively). From detailed analysis of interrelated kinetics of four oxygen-related defects, we extracted their diffusion parameters (interstitials serve as mobile recombination partners) required for the future prediction of secondary defect-induced reactions and, eventually, material radiation tolerance., (© 2021. The Author(s).)

Sensoneural hearing loss is a polyetiological disease, which is often a secondary reflection of systemic pathology and is associated with damage of the cochlea and auditory nerve receptors. An important point in the surgical stage of cochlear implantation is the introduction of an implant active electrode into the cochleostomy spiral channel through the cochleostoma or round window. However, the issue of intra-cochlear structures surgical trauma in such surgical intervention seems to be very important, as it may reduce the success of subsequent rehabilitation. Therefore, the study of the anatomy of the round window and adjuscent areas was the objective of this work.

Objectives: This study presents the data collected through a database on the type and incidence of cochlear implant device failures and major complications and quantifies the risk of failures across time based on the Association for the Advancement of Medical Instrumentation (AAMI) CI86:2017 standard. Methods: Information on reliability of MED-EL cochlear implants was collected from the MED-EL complaint database between 2003 and2013. Explants were categorized and device reliability was calculated according to the AAMI CI86:2017 standard principles. Results: Data were collected for 11662 devices (5462 children, 6200 adults). The mean duration of follow up was 46.16 months. The total failure rate for all devices and all subjects was 2.41%. Medical related explants (MRE) were significantly worse for children than for adults with the ceramic implants, C40+ ( p  = 0.008) and PULSAR ( p  = 0.020). Device failure explants (DFE) were significantly worse for children than for adults with all four devices in the study, the C40+ ( p  < 0.001), PULSAR ( p  < 0.001), SONATA ( p  < 0.001), and CONCERTO ( p  = 0.023). The mean annual failure rate for all subjects and devices was 0.63% (1.03% for children, 0.28% for adults). The mean annual failure rate was 0.90% for the C40+; 0.57% for the PULSAR; 0.46% for the SONATA; and 0.39% for the CONCERTO. Conclusions: Compared to adults, children had significantly worse MRE and DFE due to a higher risk of head trauma and more vulnerable skull anatomy. Further, the authors conclude that the AAMI standard will ensure a more comprehensive and transparent evaluation of cochlear implant reliability in the future.

MgAl 2 O 4 spinel is important optical material for harsh radiation environment and other important applications. The kinetics of thermal annealing of the basic electron (F, F + ) and hole (V) centers in stoichiometric MgAl 2 O 4 spinel irradiated by fast neutrons and protons is analyzed in terms of diffusion-controlled bimolecular reactions. Properties of MgAl 2 O 4 single crystals and optical polycrystalline ceramics are compared. It is demonstrated that both transparent ceramics and single crystals, as well as different types of irradiation show qualitatively similar kinetics, but the effective migration energy E a and pre-exponent D 0 are strongly correlated. Such correlation is discussed in terms of the so-called Meyer-Neldel rule known in chemical kinetics of condensed matter. The results for the irradiated spinel are compared with those for sapphire, MgO and other radiation-resistant materials.

The study of the effect of cochlear implantation on cognitive function is an urgent problem, since the world is increasing the population of elderly and senile people who, as a rule, have certain hearing impairments. Age-related hearing loss is one of the most common health problems associated with aging, affecting two-thirds of people over the age of 70. However, few adults are tested for hearing loss, and even fewer are being treated. It is known that hearing loss - the most common sensory deficit-forms the prerequisites for narrowing the range of cognitive functions in the elderly and can serve as a factor accelerating the progression of cognitive changes. We analyzed the available research on the effects of hearing loss and cochlear implantation on cognitive function. It was revealed that for the most part, they had a small sample, the results were not subjected to the necessary statistical analysis, and the tests used were not adapted for hearing impaired people. After analyzing different tests for assessing cognitive function, HI-MoCA and RBANS-H tests were selected, which are adapted for hearing impaired people, which will allow to reliably assess cognitive function in the pre- and postoperative period, as well as to trace the effect of cochlear implantation on cognitive function in postoperative period.

Objective: To evaluate the hearing outcomes of cochlear implantation in different age groups by using data collected in the HEARRING registry., Methods: A multicenter study. Data of 146 patients were collected in a HEARRING registry. Patients were divided into three different age groups; ≤ 55 years old (age group 1, n = 66), 56 to 69 years old (age group 2, n = 45), and ≥ 70 years old (age group 3, n = 35). Speech in quiet (SPIQ), speech in noise (SPIN), and hearing implant sound quality index (HISQUI19) scores were evaluated for the different age groups at different test moments (preoperatively, 3, 6, 12, and 24 mo after first fitting)., Results: A statistically significant difference (p < 0.01) was found between preoperative scores and the scores on all the follow-up moments across all age groups. For SPIQ and SPIN, none of the time points showed a statistically significant age effect (p = 0.88 and p = 0.89). For HISQUI19 scores, a statistically significant age effect was found at 12 months after first fitting. The oldest age group scored significantly lower on the HISQUI19 compared with the youngest age group., Conclusion: Hearing outcomes of adult cochlear implant users of different age groups were evaluated. The SPIQ and SPIN tests showed no significant differences between the different age groups. Nevertheless, the youngest group scored significantly better on self -perceived benefit (HISQUI19) with a cochlear implant compared with the oldest age group.Further research is needed to receive more insight into cochlear implantation in the elderly and its implications on rehabilitating and supporting this expanding older population.

The colloidal processing of nearly monodisperse and highly crystalline single-domain ferroelectric or ferromagnetic nanocubes is a promising route to produce superlattice structures for integration into next-generation devices, whereas controlling the local behaviour of nanocrystals is imperative for fabricating highly-ordered assemblies. The current picture of nanoscale polarization in individual nanocrystals suggests a potential presence of a significant dipolar interaction, but its role in the condensation of nanocubes is unknown. We simulate the self-assembly of colloidal dipolar nanocubes under osmotic compression and perform the microstructural characterization of their densified ensembles. Our results indicate that the long-range positional and orientational correlations of perovskite nanocubes are highly sensitive to the presence of dipoles.

Cochlear implantation is the most effective method of rehabilitation of patients with a high degree of hearing loss and deafness. This is a complex, multi-stage way of rehabilitation that includes selection of candidates for surgical intervention, a surgical stage and postoperative long-term auditory rehabilitation. In carrying out the surgical stage of cochlear implantation the round window niche area is of great interest, since the variability of its anatomical features affects the access to scala tympani. The article presents the data obtained from study of the round window niche area anatomy on cadaveric temporal bones. Variations of structures important for cochlear implantation have been determined.

Objective: To determine the time needed to remotely perform a set of intraoperative measurements during cochlear implantation surgery and to compare it to the time needed to perform the same measurements in theatre., Design: Prospective two-arm study comparing a local with a remote measurement setting. Three intraoperative measurements (Impedance Field Telemetry (IFT), evoked compound action potential (ECAP) and evoked stapedius reflex test (eSRT)) were performed with the audiologist present in the operating theatre (i.e. locally) or with the audiologist in his/her office (i.e. remotely). The time needed to complete the measurements, in total and individually, were measured and compared., Study Sample: Fifty cochlear implant recipients, aged 0.7-48 years Results: IFT, ECAP and eSRT were performed successfully in all participants. Comparing locally and remotely performed measurements, IFT did not differ significantly, ECAP threshold or slope did not differ significantly differ in any single channel and eSRT measurements did not differ significantly except for in one of six channels. Remote measurements took 8.6 min less to perform than did local measurements (10.04 vs. 18.64 min); a significant difference (p < 0.001)., Conclusions: Using a remote network connection for intraoperative objective measurements is an efficient and safe way to perform measurements during cochlear implantation surgery.

The annealing kinetics of the primary electronic F-type color centers (oxygen vacancies with trapped one or two electrons) is analyzed for three ionic materials (Al 2 O 3 , MgO, and MgF 2 ) exposed to intensive irradiation by electrons, neutrons, and heavy swift ions. Phenomenological theory of diffusion-controlled recombination of the F-type centers with much more mobile interstitial ions (complementary hole centers) allows us to extract from experimental data the migration energy of interstitials and pre-exponential factor of diffusion. The obtained migration energies are compared with available first-principles calculations. It is demonstrated that with the increase of radiation fluence both the migration energy and pre-exponent are decreasing in all three materials, irrespective of the type of irradiation. Their correlation satisfies the Meyer-Neldel rule observed earlier in glasses, liquids, and disordered materials.The origin of this effect is discussed. This study demonstrates that in the quantitative analysis of the radiation damage of real materials the dependence of the defect migration parameters on the radiation fluence plays an important role and cannot be neglected.

Objectives: To provide multidisciplinary cochlear implant teams with a current consensus statement to support hearing preservation cochlear implantation (HPCI) in children, including those children with symptomatic partial deafness (PD) where the intention is to use electric-acoustic stimulation (EAS). The main objectives are to provide guidelines on who is a candidate, how to assess these children and when to implant if Med-El Flex electrode arrays are chosen for implantation., Methods: The HEARRING group reviewed the current evidence and practice regarding the management of children to be considered for HPCI surgery emphasizing the assessment needed prior to implantation in order to demonstrate the benefits in these children over time. The consensus statement addresses following three key questions: (1) Should these children be treated? (2) How to identify these children? (3) How to manage these children?, Summary: The HEARRING group concludes that irrespective of the degree of residual hearing present, the concepts of hearing and structure preservation should be applied in every child undergoing cochlear implantation and that HPCI is a safe and reliable treatment option. Early detection and multidisciplinary assessment are key to the identification of children with symptomatic PD, these children should undergo HPCI as early as possible.

The mode of the introduction of the active electrode of a cochlear implant into the cochlea remains a key issue as far as cochlear implantation is concerned. Especially much attention has recently been given to the relationship between the anatomical features of the basal region of the cochlea (the so-called 'fish hook') and the possibility to approach it. We have undertaken the attempt to optimize the approach to the tympanic canal (scala tympanica) of the cochlea with a view to reducing to a minimum the risk of an injury to the cochlear structures in the course of cochlear implantation. A total of 35 cadaveric temporal bones were examined to measure the fine structures of the hook region and evaluate the risk of their damages associated with various approaches to the tympanic canal.

One of the many parameters that can affect cochlear implant (CI) users' performance is the site of presentation of electrical stimulation, from the CI, to the auditory nerve. Evoked compound action potential (ECAP) measurements are commonly used to verify nerve function by stimulating one electrode contact in the cochlea and recording the resulting action potentials on the other contacts of the electrode array. The present study aimed to determine if the ECAP amplitude differs between the apical, middle, and basal region of the cochlea, if double peak potentials were more likely in the apex than the basal region of the cochlea, and if there were differences in the ECAP threshold and recovery function across the cochlea. ECAP measurements were performed in the apical, middle, and basal region of the cochlea at fixed sites of stimulation with varying recording electrodes. One hundred and forty one adult subjects with severe to profound sensorineural hearing loss fitted with a Standard or FLEX SOFT electrode were included in this study. ECAP responses were captured using MAESTRO System Software (MED-EL). The ECAP amplitude, threshold, and slope were determined using amplitude growth sequences. The 50% recovery rate was assessed using independent single sequences that have two stimulation pulses (a masker and a probe pulse) separated by a variable inter-pulse interval. For all recordings, ECAP peaks were annotated semi-automatically. ECAP amplitudes were greater upon stimulation of the apical region compared to the basal region of the cochlea. ECAP slopes were steeper in the apical region compared to the basal region of the cochlea and ECAP thresholds were lower in the middle region compared to the basal region of the cochlea. The incidence of double peaks was greater upon stimulation of the apical region compared to the basal region of the cochlea. This data indicates that the site and intensity of cochlear stimulation affect ECAP properties.

The objective of the present study was to determine the thresholds of electrically evoked short-latent auditory potentials by the mathematical method and to elucidate the relationship between these parameters and the subjective maximally comfortable levels in the patients undergoing cochlear implantation. The electrically evoked short-latent auditory potentials were recorded in two groups of patients with different stimulation frequency (17 and 43 Hz). The use of the mathematical method of linear regression of the amplitude (peak V) growth function for determining the thresholds of electrically evoked short-latent auditory potentials has a number of advantages over visual detection of the threshold level. To increase the reliability of the data obtained, low stimulation frequencies need to be used when recording electrically evoked short-latent auditory potentials (17 Hz). The calculated thresholds of electrically evoked short-latent auditory potentials can be used to estimate the subjective maximally comfortable levels for the adjustment of the speech processors when it is impossible to register electrically induced stapedial reflexes and electrically induced total action potentials of the auditory nerve in the patients having cochlear implants.

Conclusion The study demonstrates the medium-term stability and safety of the CONCERTO PIN cochlear implant. The use of the CONCERTO PIN proved to be suitable for the use of a surgical technique without the need for suture fixation and resulted in short surgery duration and a low medium-term complication rate. Objective The primary aim was to provide data on medium-term safety and stability of the CONCERTO PIN cochlear implant in adults and children, and to collect feedback on the surgical technique used, which involved no drilling and no suture fixation. The secondary aim was to analyze surgery duration. Methods Implantation was performed using minimally invasive surgery. During surgery, data on the surgical procedure was collected by the attending surgeons or a designee. Safety and stability of the CONCERTO PIN were assessed at first fitting (1 month after implantation) and 6 months after first fitting. Results Ninety-nine patients were implanted with a CONCERTO PIN implant and one patient with a CONCERTO implant. The CONCERTO PIN implants implanted during this study were immobilized by pins and a tight periosteal pocket. The mean (± SD) surgery duration was 27:52 (± 9:19) min.

Conclusion: Bone conduction implants are useful in patients with conductive and mixed hearing loss for whom conventional surgery or hearing aids are no longer an option. They may also be used in patients affected by single-sided deafness., Objectives: To establish a consensus on the quality standards required for centers willing to create a bone conduction implant program., Method: To ensure a consistently high level of service and to provide patients with the best possible solution the members of the HEARRING network have established a set of quality standards for bone conduction implants. These standards constitute a realistic minimum attainable by all implant clinics and should be employed alongside current best practice guidelines., Results: Fifteen items are thoroughly analyzed. They include team structure, accommodation and clinical facilities, selection criteria, evaluation process, complete preoperative and surgical information, postoperative fitting and assessment, follow-up, device failure, clinical management, transfer of care and patient complaints.

In the description of charge screening in the electrostatic self-assembly of nanoparticles (molecules) embedded into a polar solvent, the static screening effects (a contribution associated with the rapid spatial redistribution of small and highly mobile ions of a solvent) are traditionally treated phenomenologically, using the Yukawa short-range potential for describing the interaction between these particles. However, this model has a limited range of applicability being valid only for infinitely diluted systems and high salt concentrations. During a slow self-assembling process with nanoparticle formation, very dense structural elements (aggregates) are formed, in which the distances between the nanoparticles could become comparable to the Debye radius in the Yukawa potential. For such structural elements dynamic screening effects (the contribution of nanoparticles themselves to the screening potential) become important. In this paper, using a novel integrated approach (nonlinear integro-differential kinetic equations for the correlation functions of particles), we have obtained the self-consistent solution in the 3d case and compared roles of both static (equilibrium) and dynamic (nonequilibrium) charge screening effects in different situations. This paper is a continuation of our recent study [Phys. Chem. Chem. Phys., 2014, 16, 13974], where the polar solvent effects were now taken into account.

A study of 3d electrostatic self-assembly (SA) in systems of charged nanoparticles (NPs) is one of the most difficult theoretical problems. In particular, the limiting case of negligible or very low polar media (e.g. salt) concentration, where the long-range NP interactions cannot be reduced to commonly used effective short-range (Yukawa) potentials, remains unstudied. Moreover, the present study has demonstrated that unlike the Debye-Hückel theory, a complete screening of the charges in SA kinetics (dynamic SA) is not always possible. Generally speaking, one has to take into account implicitly how each NP interacts with all other NPs (the true long-range interactions). Traditional theoretical methods allow us to monitor such electrostatic 3d system kinetics only for very short times, which is far from sufficient for understanding the dynamic SA. In this paper, combining an integrated analytical approach (the non-linear integro-differential kinetic equation for correlation functions) and reverse Monte Carlo in the 3d case, we have obtained a self-consistent solution of this challenging problem. We demonstrate, in particular, the existence of critical points and critical phenomena in the non-equilibrium kinetics in a 3d system of oppositely charged mobile NPs.

Conclusion: Remote programming is safe and is well received by health-care professionals and cochlear implant (CI) users. It can be adopted into clinic routine as an alternative to face-to-face programming., Objectives: Telemedicine allows a patient to be treated anywhere in the world. Although it is a growing field, little research has been published on its application to CI programming. We examined hearing professionals' and CI users' subjective reactions to the remote programming experience, including the quality of the programming and the use of the relevant technology., Methods: Remote CI programming was performed in Italy, Sweden, and Russia. Programming sessions had three participants: a CI user, a local host, and a remote expert. After the session, each CI user, local host, and remote expert each completed a questionnaire on their experience., Results: In all, 33 remote programming sessions were carried out, resulting in 99 completed questionnaires. The overwhelming majority of study participants responded positively to all aspects of remote programming. CI users were satisfied with the results in 96.9% of the programming sessions; 100% of participants would use remote programming again. Although technical problems were encountered, they did not cause the sessions to be considerably longer than face-to-face sessions.

Conclusion: The comprehensive Hearing Preservation classification system presented in this paper is suitable for use for all cochlear implant users with measurable pre-operative residual hearing. If adopted as a universal reporting standard, as it was designed to be, it should prove highly beneficial by enabling future studies to quickly and easily compare the results of previous studies and meta-analyze their data., Objectives: To develop a comprehensive Hearing Preservation classification system suitable for use for all cochlear implant users with measurable pre-operative residual hearing., Methods: The HEARRING group discussed and reviewed a number of different propositions of a HP classification systems and reviewed critical appraisals to develop a qualitative system in accordance with the prerequisites., Results: The Hearing Preservation Classification System proposed herein fulfills the following necessary criteria: 1) classification is independent from users' initial hearing, 2) it is appropriate for all cochlear implant users with measurable pre-operative residual hearing, 3) it covers the whole range of pure tone average from 0 to 120 dB; 4) it is easy to use and easy to understand.

The purpose of the present study was to develop a method for the objective registration of the stapedial reflex at the contralateral ear during cochlear implantation surgery on the affected one. The excessive pressure in the middle ear (up to 500 daPa) was compensated by the administration of an additional air volume (1 liter) into the AA220 impedance meter pneumatic circuit. A syringe was used to measure variations of pressure in the new pneumatic circuit. Eight of the 12 patients demonstrated coincident visual and objective reflex thresholds. In the remaining 4 patients, the visually apparent stapedial reflex thresholds proved higher than those obtained objectively by the standard procedure of impedancemetry. It is concluded that the objective registration of the stapedial reflex excludes the effect of subjective factors interfering with its estimation and provides the possibility for comparative intra- and postoperative studies using one and the same instrument.

We performed kinetic Monte Carlo simulations on a model of a polymerization process in the presence of a periodic oscillatory flow to explore the role of mixing in polymerization reactors. Application of an oscillatory flow field helps overcome the diffusive limitations that develop during a polymerization process due to an increase in the molecular weights of polymer chains, thereby giving rise to high rates of polymerization. A systematic increase in the flow strength results in a "dynamic" coil-stretch transition, leading to an elongation of polymer chains. Reactive ends of stretched (polymer) chains react more frequently than the reactive ends of coiled chains, which are screened by other monomers of the same chain. There exists a critical flow strength for the efficiency of polymerization processes. The kinetic Monte Carlo simulation scheme developed here exhibit great promise for the study of dynamic properties of polymer systems.

The kinetics of pattern formation and phase separation in a system of two types of oppositely charged molecules with competing short- and long-range interactions on surfaces/interfaces is studied combining three methods: a microscopic formalism of the joint correlation functions, reverse Monte Carlo, and nonequilibrium charge-screening factors. The molecular ordering occurs on the background of the Ostwald ripening and thus is strongly nonequilibrium. We have demonstrated how initial random distribution of molecules is changed for loose similar-molecule aggregates, with further reorganization into dense macroscopic domains of oppositely charged molecules. Pattern formation process is characterized by the correlation length which monotonically increases in time.

The kinetics of mesoscopic pattern formation is studied for a reversible A+B⇌0 reaction between mobile oppositely charged molecules at the interface. Using formalism of the joint correlation functions, non-equilibrium charge screening and reverse Monte Carlo methods, it is shown that labyrinth-like percolation structure induced by (even moderate-rate) reaction is principally non-steady-state one and is associated with permanently growing segregation of dissimilar reactants and aggregation of similar reactants into mesoscopic size domains. A role of short-range and long-range reactant interactions in pattern formation is discussed., (© 2011 American Institute of Physics)

The effects of non-equilibrium charge screening in mixtures of oppositely charged interacting molecules on surfaces are analyzed in a closed system. The dynamics of charge screening and the strong deviation from the standard Debye-Hückel theory are demonstrated via a new formalism based on computing radial distribution functions suited for analyzing both short-range and long-range spacial ordering effects. At long distances the inhomogeneous molecular distribution is limited by diffusion, whereas at short distances (of the order of several coordination spheres) by a balance of short-range (Lennard-Jones) and long-range (Coulomb) interactions. The non-equilibrium charge screening effects in transient pattern formation are further quantified. It is demonstrated that the use of screened potentials, in the spirit of the Debye-Hückel theory, leads to qualitatively incorrect results.

The concept of remote long-term support of the patients with cochlear implants is suggested to cope with the problem of the increasingly growing number of patients with cochlear pathology. The authors deem it necessary to provide intraoperative support and postoperative follow-up technologies for the patients living far from the cochlear implantation centres. A scheme for the remote selection of patients and their intraoperative monitoring is proposed with the use of implant telemetry, electrical stapedial reflex (eSRT) testing, auditory response telemetry (ART), and surgical on-line counseling. Remote follow-up and rehabilitation should include cochlear implant tuning, speech therapy, and on-line workshops for the patients and/or specialists. The choice and the use of software and hardware for this purpose are discussed. The concept of remote long-term support turned out to be an efficacious, reliable, time-saving, and cost-effective tool for providing high-tech medical aid to patients with ENT diseases in the Krasnoyarsk kray (territory).

A microscopic formalism based on computing many-particle densities is applied to the analysis of the diffusion-controlled kinetics of pattern formation in oppositely charged molecules on surfaces or adsorbed at interfaces with competing long-range Coulomb and short-range Lennard-Jones interactions. Particular attention is paid to the proper molecular treatment of energetic interactions driving pattern formation in inhomogeneous systems. The reverse Monte Carlo method is used to visualize the spatial molecular distribution based on the calculated radial distribution functions (joint correlation functions). We show the formation of charge domains for certain combinations of temperature and dynamical interaction parameters. The charge segregation evolves into quasicrystalline clusters of charges, due to the competing long- and short-range interactions. The clusters initially co-exist with a gas phase of charges that eventually add to the clusters, generating "fingers" or line of charges of the same sign, very different than the nanopatterns expected by molecular dynamics in systems with competing interactions in two dimensions, such as strain or dipolar versus van der Waals interactions.

We discuss an alternative to the traditional gas-phase coupling approach in order to explain synchronized global oscillations in CO oxidation on Pt(110). We use a microscopic model which includes structural Pt surface reconstruction via front propagation, and large diffusion rates for CO. The synchronization mechanism is associated with the formation of a Turing-like structure of the substrate. By using large parallel microscopic simulations we derive scaling laws which allow us to extrapolate to realistic diffusion rates, pattern size, and oscillation periods.

We show the existence of internal stochastic resonance in a microscopic stochastic model for the oscillating A+1 / 2B(2) reaction on a square lattice. This stochastic resonance arises directly from the elementary reaction steps of the system without any external input. The lattice gas model is investigated by means of Monte Carlo simulations. It shows oscillation phenomena and mesoscopic pattern formation. Stochastic resonance arises when homogeneous nucleation of the individual lattice site states is considered. This nucleation is modeled as a weak noise process. As a result, synchronization of the kinetic oscillations is obtained. We show that all characteristics known from the research on stochastic resonance are obtained in our model. We also show that the model explains easily several phenomena observed in the experiment. Internal stochastic resonance may thus be an internal regulation mechanism of extreme adaptability.

The A+B-->0 reaction model with a surface reconstruction is analyzed. It is compared with another similar model for the A+1/2B2-->0 reaction [V. N. Kuzovkov et al., J. Chem. Phys. 108, 5571 (1998)], which mimics the CO oxidation reaction on the Pt surfaces. The effect of monomer B adsorption instead of dimer B2 is examined. It is shown that qualitative system features such as reactant concentration oscillations are independent of this substitution.

A microscopic kinetic model for the alpha <==> beta [e.g., hex <==> 1x1 for Pt(100) and 1x2 <==> 1x1 for Pt(110)] surface reconstruction is investigated by means of the mean field approximation and Monte Carlo simulations. It considers homogeneous phase nucleation that induces small surface phase defects. These defects can grow or decline via phase border propagation in dependence on the chemical coverage by an adsorbate A (CO). An asymmetry in the adsorbate surface diffusion from one surface phase to the other gives rise to two critical coverages that determine the intervals of stability of the homogeneous alpha phase, the dynamically stable heterogeneous state, and the homogeneous beta phase. Both surfaces show a very similar qualitative behavior regarding the phase transitions that are of second order in both cases. As a result the experimentally observed nonlinear island growth rate and the critical coverages can be explained at a quantitative level.

We reply to the Comment by Zhdanov [preceding paper, Phys. Rev. E 65, blacksquare, square, filled (2002)] on our recent paper [G. Zvejnieks and V. N. Kuzovkov, Phys. Rev. E 63, 051104 (2001)]. We demonstrate that our quite different viewpoints result, in fact, entirely from nonunique definitions of the master equation, which has nothing to do with neglecting important physical principles, as Zhdanov claims.

The microscopic one-parameter kinetic model of the oscillatory A+B-->2 B reaction (Lotka model) is studied using direct Monte Carlo simulations and analytical methods. Percolation is proposed as the mechanism of global oscillations that are not limited to any finite size of a system. An analytical estimate of the oscillation frequency is derived and compared to computer simulations. We also observe the transition from synchronized oscillations to specific f(-2) noise in two dimensions which was previously reported for self-organized critical models.

The standard Lotka-type model, which was introduced for the first time by Mai et al. [J. Phys. A 30, 4171 (1997)] for a simplified description of autocatalytic surface reactions, is generalized here for a case of mobile and energetically interacting reactants. The mathematical formalism is proposed for determining the dependence of transition rates on the interaction energy (and temperature) for the general mathematical model, and the Lotka-type model, in particular. By means of Monte Carlo computer simulations, we have studied the impact of diffusion (with and without energetic interactions between reactants) on oscillatory properties of the A+B-->2B reaction. The diffusion leads to a desynchronization of oscillations and a subsequent decrease of oscillation amplitude. The energetic interaction between reactants has a dual effect depending on the type of mobile reactants. In the limiting case of mobile reactants B the repulsion results in a decrease of amplitudes. However, these amplitudes increase if reactants A are mobile and repulse each other. A simplified interpretation of the obtained results is given.

In a recent article Zhdanov studied the oscillating NO+H2 reaction on the Pt(100) single-crystal surface [V. P. Zhdanov, Phys. Rev. E 59, 6292 (1999)]. We have scrutinized his model and found fundamental errors in the chemical modeling, in the modeling of the surface reconstruction and in the simulation procedure itself.