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Purpose: Studies have assessed the trauma and change in hearing function from the use of otological drills on the ossicular chain, but not the effects of partial laser ablation of the incus. A study of the effectiveness of a novel middle-ear microphone for a cochlear implant, which required an incus recess for the microphone balltip, provided an opportunity to compare methods and inform a feasibility study of the microphone with patients. Methods: We used laser Doppler vibrometry with an insert earphone and probe microphone in 23 ears from 14 fresh-frozen cadavers to measure the equivalent noise level at the tympanic membrane that would have led to the same stapes velocity as the creation of the incus recess. Results: Drilling on the incus with a diamond burr created peak noise levels equivalent to 125.1–155.0 dB SPL at the tympanic membrane, whilst using the laser generated equivalent noise levels barely above the baseline level. The change in middle ear transfer function following drilling showed greater variability at high frequencies, but the change was not statistically significant in the three frequency bands tested. Conclusions: Whilst drilling resulted in substantially higher equivalent noise, we considered that the recess created by laser ablation was more likely to lead to movement of the microphone balltip, and therefore decrease performance or result in malfunction over time. For patients with greatly reduced residual hearing, the greater consistency from drilling the incus recess may outweigh the potential benefits of hearing preservation with laser ablation. [ABSTRACT FROM AUTHOR]

It is 50 years since Sieveking et al. published their pioneering research in Nature on the geochemical analysis of artefacts from Neolithic flint mines in southern Britain. In the decades since, geochemical techniques to source stone artefacts have flourished globally, with a renaissance in recent years from new instrumentation, data analysis, and machine learning techniques. Despite the interest over these latter approaches, there has been variation in the quality with which these methods have been applied. Using the case study of flint artefacts and geological samples from England, we present a robust and objective evaluation of three popular techniques, Random Forest, K-Nearest-Neighbour, and Support Vector Machines, and present a pipeline for their appropriate use. When evaluated correctly, the results establish high model classification performance, with Random Forest leading with an average accuracy of 85% (measured through F1 Scores), and with Support Vector Machines following closely. The methodology developed in this paper demonstrates the potential to significantly improve on previous approaches, particularly in removing bias, and providing greater means of evaluation than previously utilised. [ABSTRACT FROM AUTHOR]

Many passengers experience discomfort during flight because of the effect of low humidity on the skin, eyes, throat, and nose. In this physiological study, we have investigated whether flight and low humidity also affect the tympanic membrane. From previous studies, a decrease in admittance of the tympanic membrane through drying might be expected to affect the buffering capacity of the middle ear and to disrupt automatic pressure regulation. This investigation involved an observational study onboard an aircraft combined with experiments in an environmental chamber, where the humidity could be controlled but could not be made to be as low as during flight. For the flight study, there was a linear relationship between the peak compensated static admittance of the tympanic membrane and relative humidity with a constant of proportionality of 0.00315 mmho/% relative humidity. The low humidity at cruise altitude (minimum 22.7 %) was associated with a mean decrease in admittance of about 20 % compared with measures in the airport. From the chamber study, we further found that a mean decrease in relative humidity of 23.4 % led to a significant decrease in mean admittance by 0.11 mmho [ F(1,8) = 18.95, P = 0.002], a decrease of 9.4 %. The order of magnitude for the effect of humidity was similar for the flight and environmental chamber studies. We conclude that admittance changes during flight were likely to have been caused by the low humidity in the aircraft cabin and that these changes may affect the automatic pressure regulation of the middle ear during descent. [ABSTRACT FROM AUTHOR]

As the numbers of international students have grown, higher education institutions in Asia have offered a growing range of English medium instruction (EMI) degree programs. But Asian governments and higher education institutions have not thought deeply about how to ensure quality of English medium instruction degree programs. At the same time, their accreditors have not been fully aware of how to establish an external quality assurance mechanism to measure the quality of these programs. This study's main purpose is to put the quality of the EMI degree programs of Taiwan higher education institutions into the perspective of the Taiwan's institutions and one local Taiwan accreditor. With both qualitative and quantitative approaches, a survey targeting Taiwan's colleges and universities and interviews of Higher Education Evaluation & Accreditation Council of Taiwan international reviewers and Asian higher education experts are used to examine the challenges of EMI implementation in Taiwan universities and the role of local accreditors playing in reviewing the English medium instruction degree programs. [ABSTRACT FROM AUTHOR]

In order to help students make well-informed choices, reliable college ranking systems with comparable information about higher education institutions worldwide have been welcomed by many students. Because traditional college rankings had many methodological problems, a new type of user-based ranking, called 'personalized college ranking' started to develop in many nations in the late 1990s. In 2008, Higher Education Evaluation and Accreditation Council of Taiwan (HEEACT), launched a ranking project called 'College Navigator in Taiwan' which developed the first Asian student-based college search engine to provide local and international students with transparent information on Taiwan's higher education institutions. The main objective of this paper, therefore, is to compare the rational, strategies and pathways for establishing personalized college rankings. In order to analyze the gap between students' preferences and university presidents' concerns over ranking indicators, HEEACT's 'College Navigator in Taiwan' is adopted as a case study at the end of paper. [ABSTRACT FROM AUTHOR]

The childhood disorder spinal muscular atrophy (SMA) is caused by reduced expression of the survival motor neuron (SMN) protein. SMN is a multifunctional protein that has been implicated in the production, processing and transport of RNA and ribonucleoproteins (RNPs). Within the nucleus, SMN is predominantly targeted to Cajal bodies (CB), which are involved in the maturation and processing of several subclasses of RNPs. Here, we show that the SMN exon 2b-encoded domain (SMN2b) is independently sufficient to mediate CB targeting, but that the resulting bodies are less dynamic than those containing full-length SMN protein. We also show that while two SMN proteins harbouring SMA-causing point mutations (A2G and S262I) are efficiently targeted to CBs, they also display reduced nuclear movement. [ABSTRACT FROM AUTHOR]

The legend of Figure 8: "Learning curve shows F1 score for train and test data against number of observations in training data." now reads: "Box Plot of F1 Scores for each model, showing good equality of variances." ( B b b ) Learning curve shows F1 score for train and test data against number of observations in training data." now reads: "Learning curve shows F1 score for train and test data against number of observations in training data." The legend of Figure 9: "Evaluation of data ( B a b ) Scatter plot showing F1 scores for models built on features selected by recursive feature elimination. [Extracted from the article]

The deliberate addition of Gaussian noise to cochlear implant signals has previously been proposed to enhance the time coding of signals by the cochlear nerve. Potentially, the addition of an inaudible level of noise could also have secondary benefits: it could lower the threshold to the information-bearing signal, and by desynchronization of nerve discharges, it could increase the level at which the information-bearing signal becomes uncomfortable. Both these effects would lead to an increased dynamic range, which might be expected to enhance speech comprehension and make the choice of cochlear implant compression parameters less critical (as with a wider dynamic range, small changes in the parameters would have less effect on loudness). The hypothesized secondary effects were investigated with eight users of the Clarion cochlear implant; the stimulation was analogue and monopolar. For presentations in noise, noise at 95% of the threshold level was applied simultaneously and independently to all the electrodes. The noise was found in two-alternative forced-choice (2AFC) experiments to decrease the threshold to sinusoidal stimuli (100 Hz, 1 kHz, 5 kHz) by about 2.0 dB and increase the dynamic range by 0.7 dB. Furthermore, in 2AFC loudness balance experiments, noise was found to decrease the loudness of moderate to intense stimuli. This suggests that loudness is partially coded by the degree of phase-locking of cochlear nerve fibers. The overall gain in dynamic range was modest, and more complex noise strategies, for example, using inhibition between the noise sources, may be required to get a clinically useful benefit. [ABSTRACT FROM AUTHOR]

In this paper we determine the nonabelian tensor square of the free 2-Engel group of rank 3 and of the Burnside group on 3 generators of exponent 3. Both tensor squares are nilpotent groups of class 2. The calculatory method used is based on the concept of a crossed pairing. Some of the expansion formulas and verifications occuring in this context require extensive calculations. A computer program written in the GAP language assisted in completing these symbolic computations. [ABSTRACT FROM AUTHOR]