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Unhomogenized and homogenized AA8006 (Al-Fe-Mn-Si) alloy sheets twin-roll cast to strip 8.5 mm thick, processed by accumulative roll-bonding (ARB) on 2 mm thick sheets up to 6 cycles were studied. The microstructure was characterized by means of scanning and transmission electron microscopy and electron backscattered diffraction (EBSD), mechanical properties were monitored by hardness measurements and tensile tests. The macroscopic texture was determined by X-ray diffraction. The initial texture of the unhomogenized sheet is rotated cubic {001} combined with recrystallization R texture {011}, while the homogenized sheet has a cubic texture {001} with remaining rolling component C {112}. One ARB cycle leads to the formation of low-angle grain boundaries (LAGB) in original coarser grains and to a low angle rotation of the subgrains bounded by LAGB. After the 3rd and 6th ARB cycle unhomogenized and homogenized sheets show a common rolling texture of cold-rolled aluminium. The thermal stability of sheets processed by 6 ARB cycles was tested by isochronal annealing for 30 min up to 450°C. The homogenized sheet starts to recrystallize at 250°C, while the fine grain structure of the unhomogenized sheet is thermally stable up to 400°C.

Evaluation of insertion of a cochlear implant electrode into the cochlea includes radiological techniques: plain X-ray of the skull, cochlear projection (based on Stenvers projection), computer tomography. These methods allow generally postoperative evaluation. During surgery the insertion of the electrode is assessed based on anatomical structures and markers placed on the electrode. The measurement of the electrode impedance is also an important tool. 60 patients implanted with the Contour cochlear implant with pre-shaped electrode were examined. Age o patients: mediana 4.25 (1.5-54.5). Examination includes intraoperative impedance measurement performed in two stages: (1) after the electrode insertion, and (2) after removal of the stylet. Measurements were done in Common Ground (CG) and Monopolar 1 (MP1) stimulation modes. Measurements recorded in two modes and in 3 different parts of the cochlea (apical, middle, basal) were compared. The average difference value (before-after) was for the CG mode: 0.45 kΩ and for the MP1 mode: 0.39 kΩ. For the CG mode the difference values were: 0.64, 0.44 and 0.28 toward apical part. For the MP1 mode the difference values were: 0.47, 0.43 and 0.27 toward apical part of the cochlea. [ABSTRACT FROM AUTHOR]

The aim of the study was to analyse the causes for cochlear implant explantations in our Cochlear Implant Program. Material and methods: The cochlear implant program in our department started in 1994 and till now we have performed 1418 cochlear implantations. This group consists of 799 children and 619 adults. The medical charts of patients were retrospectively analysed to find the cases which required explantation. Results and conclusions: Explantation was performed in 50 cases (3.5%). There were the following reasons of explantation found: 1) documented failure of the internal device (19 cases), 2) decreased performance over time (2 cases), 3) unsatisfactory placement of the electrode array (7 cases), 4) technological upgrade (1 case), 5) scalp flap complications (15 cases) and 6) intratemporal pathology (6 cases). [ABSTRACT FROM AUTHOR]

The aim of the study was to present how the Universal Neonatal Hearing Screening Program in Poland works and its influence on number of implanted small children in Poznań. The Universal Neonatal Hearing Screening Program in Poland began in the end of 2002. The main structure of the program consists of three levels. Neonate Departments are responsible for EOAE tests in all newborns in their first 2-3 days of life. On the second level at the age of 3 months children undergo OAE and ABR test. The third level is responsible for treatment of hearing-impaired children. The first hearing screened children were implanted with cochlear implants in our centre in 2005. The cochlear implant programme in Poznan started in 1994. Till now we have performed 1418 cochlear implantations. This group consists of 799 children and 619 adults. Until now 378 cochlear implants in children under 3 years of age were implanted. Between 2000-2004 only 1-9 children per year below 3 years of age were operated on. From 2005-2017 a number of children implanted below 3 increased till 16-30 per year. Poznan Cochlear implanted program was sequentially adapted to work with small children after implantation. The program enabled early audiological intervention, including early cochlear implantation and influenced educational skills. [ABSTRACT FROM AUTHOR]

The effects on the adsorption of fluoroquinolone antibiotics of long-term soil heterogeneity induced by land-use were investigated. Three different land use areas with their two organic matter (OM) pools were tested for the adsorption of three antibiotics widely detected in the environment (ciprofloxacin, norfloxacin, ofloxacin). The soils were separated into two size fractions, > 63 µm fraction and < 63 µm fractions for the fast and slow OM pools, respectively. Any effect of land use on adsorption was only observed in the slow pool in the increasing order: arable land, grassland, and forest. The composition of the soil organic matter (SOM) did influence adsorption in the slow pool, but not in the bulk soilsThis was, because: 1) the ratio of the slow pool was low, as in forest, 2) the ratio of the slow pool was high but its adsorption capacity was low due to its SOM composition, as in arable land and grassland. Soils containing a large slow SOM pool fraction with aliphatic dominance were found to be more likely to adsorb micropollutants. It is our contention that the release of contaminated water, sludge, manure or compost into the environment should only be undertaken after taking this into consideration., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Tinnitus is a sensation of ringing in the ears in the absence of any physical source in the environment. Between 9-35% of adults experience some form of tinnitus. Common causes of tinnitus include noise, head injury, ototoxic substances, as well as disorders of blood and blood vessels. Vascular causes include: head-neck tumours, turbulent blood flow, problems with blood supply and inner ear cell damage. The aspect of rheology in terms of tinnitus has not been described yet. In the present study, which comprised 12 patients aged 30 to 74 years presenting with tinnitus, rheological properties of whole blood and plasma were assessed. All the subjects underwent audiological and neurological evaluation. The Quemada model was used to describe the variability of red blood cell shape, as well as their tendency to form aggregates. On the basis of the experimental study, statistically different results of haemorheological measurements were observed in the evaluated group in comparison to a reference group.

Introduction: Surgical treatment of deafness by cochlear implants is used for more than 40 years, and during this period permanently, gradual and significant expansion of indications for this surgery has been observed., Material and Methods: In our Department in the years 1994-2018 1480 cochlear implantations were performed, both in adults (647) and in children (883). In this study current indications and the rules for eligibility of patients based on 25 years of experience are presented., Results: Indications for cochlear implantation in adults are: 1) bilateral postlingual deafness, 2) bilateral sensorineural hearing loss - in pure tone audiometry &gt; 70 dB HL (average 500-4000 Hz) and in speech audiometry in hearing aids understanding &lt; 50% of words for the intensity of the stimulus 65 dB, in the absence of the benefits of hearing aids, 3) bilateral profound hearing loss for high frequency with good hearing for low frequency, in the absence of the benefits of hearing aids, 4) some cases of asymmetric hearing loss with intensive tinnitus in the deaf ear. An indication in children is bilateral sensorineural hearing loss &gt; 80dB HL confirmed by hearing tests, after about 6 months of rehabilitation with the use of hearing aids., Discussion: Although cochlear implantation is used for more than 40 years, the indications for this treatment underlies constant modifications. They concern the age of eligible patients, implantation in patients with partially preserved hearing, as well as treatment for patients with difficult anatomical conditions. In many countries, bilateral implantations are commonly performed, and more and more centers recommend this treatment in the case of unilateral deafness or asymmetric hearing loss, especially with the accompanying tinnitus in the deaf ear.

Introduction: Profound hearing loss significantly affects the quality of life of deaf people as well as their families. Observation of the benefit from the use of cochlear implants in deaf patients allows to assess the success of treatment with this method and its impact on the quality of life of these patients. The aim of this study was to determine the quality of life in patient after the cochlear implantation in the material of Department of Phoniatrics and Audiology of the Medical University in Poznań., Material and Methods: The study involved implanted patients who voluntarily joined to the project entitled &quot;Observational study of the implanted patient (Cochlear-IROS)&quot;. It has a prospective character, it is an international and long-term study, covering the observation of patients up to three years after implantation. Standardized HUI and SSQ questionnaires were used. 70 patients were included in the analysis, the mean age at the time of the cochlear implantation was 47.6 years. In the research group there were 33 men and 37 women. In the whole group, the patients&apos; age at implantation was at least 18 years, max. 80 years., Results: The results of the SSQ questionnaire, which deals with the self-assessment of hearing ability in everyday situations, indicate that in the subjective assessment of patients one year after surgery the speech hearing improved by 77%, spatial hearing by 84%, and the quality of hearing by 49%. The general quality of life before the first connection of the sound processor according to the HUI questionnaire, the patients rated at 0.49 (0-1 scale, where 0 - corresponds to the death condition and 1 - full health). After one year from the implantation, this rating increased to 0.56., Conclusions: The implantation of the cochlear implant significantly increases the patient&apos;s quality of life, its physical and emotional functioning. Statistically significant better self-assessment of patients mainly concerned hearing speech and spatial hearing - especially after 1 year of connecting the speech processor.

Objective: To present qualification criteria, surgery, and results of cochlear implantation via the middle fossa approach., Study Design: A retrospective analysis of medical charts of patients., Setting: Cochlear implant program in academic medical center., Patients: Six adults after middle ear surgery due to chronic otitis media with bilateral deafness or profound hearing loss., Intervention: Analysis aimed to identify patients qualified for cochlear implantation via middle fossa approach and to present surgery and result., Main Outcome Measure: Qualification criteria, details of surgery and surgical, functional and audiological results., Results: Surgery was completed in four patients and in the remaining two it was stopped because of adhesions and bleeding from the dura. In three patients, there were no postoperative complications and in one individual intracranial hematoma occurred. Postoperative computed tomography showed the intracochlear position of the electrode in all the implanted patients. All of the patients use their implant for 14 to 16 hours daily. One year after the implantation, they had hearing thresholds in the sound-free field of between 25 and 45 dB sound pressure level, number recognition scores between 80 and 100% and monosyllabic words recognition between 30 and 90%., Conclusion: Successful cochlear implantation via middle fossa approach results in satisfactory hearing, bringing deaf people into a hearing environment. However, this approach is technically difficult and provides the risk of intracranial complications. In our opinion this approach should be used in special cases only (e.g., postmeningitis or otosclerotis patients with obliteration of basal turn of cochlea). In analysed group it should not be considered the primary solution.