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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]

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]

Important research by Rosowski et al. [Twenty-Seventh Meeting of the Association for Research in Otolaryngology, 2004, p. 275] has led to a standard practice by the American Society for Testing Materials [West Conshohocken: ASTM International; 2014] to assess normal function of temporal bones used in the development of novel middle ear actuators and sensors. Rosowki et al. [Audiol Neurotol. 2007; 12(4): 265-76] have since suggested that the original criteria are too restrictive and have proposed modified criteria. We show that both the original and modified criteria are inappropriate for assessing individual temporal bones. Moreover, we suggest that both the original and modified Rosowski criteria should be applied with caution when assessing whether mean data from a study are within physiological norms because the multiple comparisons resulting from verification at each frequency will lead to very liberal rejection. The standard practice, however, has led to the collection of more extensive and consistent data. We suggest that it is now opportune to use these data to further modify the Rosowski criteria. [ABSTRACT FROM AUTHOR]

Objectives: Globally, less than 1% of people who could benefit from a cochlear implant have one and the problem is particularly acute in lower-income countries. Here we give a narrative review of the economic and logistic feasibility of cochlear implant programmes in lower-income countries and discuss future developments that would enable better healthcare. We review the incidence and aetiology of hearing loss in low- and middle-income countries, screening for hearing loss, implantation criteria, issues concerning imaging and surgery, and the professional expertise required. We also review the cost of cochlear implantation and ongoing costs. Findings: The cost effectiveness of cochlear implants in lower-income countries is more limited by the cost of the device than the cost of surgery, but there are also large ongoing costs that will deter many potential users. Conclusions: We conclude that the main barriers to the future uptake of cochlear implants are likely to be logistical rather than technical and cochlear implant provision should be considered as part of a wider programme to improve the health of those with hearing loss. [ABSTRACT FROM AUTHOR]

Totally implantable cochlear implants may be able to address many of the problems cochlear implant users have around cosmetic appearances, discomfort, and restriction of activities. The major technological challenges that need to be solved to develop a totally implantable device relate to implanted microphone performance. Previous attempts at implanting microphones for cochlear implants have not performed as well as conventional cochlear implant microphones, and in addition have struggled with extraneous body or surface contact noise. Microphones can be implanted under the skin or act as sensors in the middle ear; however, evidence from middle ear implants suggest body and contact noise can be overcome by converting ossicular chain movements into digital signals. This article reviews implantable microphone systems and discusses the technology behind them. [ABSTRACT FROM PUBLISHER]

Since the 1950s, the Council of Europe has established conventions and information networks to enhance student mobility and qualification recognition in Europe. In contrast, Asia did not take this issue into consideration until 1983, when the UNESCO Regional Convention on the Recognition of Studies, Diplomas and Degrees in Higher Education in Asia and the Pacific (the ‘1983 Convention’) was adopted. The recognition of a joint degree when the schools are in two different countries is even more challenging than for a conventional degree, because they do not belong to any single national higher education system. The first purpose of this study is to describe the current situation in the recognition of foreign qualifications in higher education institutions in Europe and Asia. Next, schemes, procedures and challenges for recognizing a joint degree will be analyzed. The role of recognition bodies and quality assurance agencies in qualification recognition will be discussed at the end of the paper. [ABSTRACT FROM AUTHOR]

An essay is presented concerning whether the promise of informed consent in medical law meets the standard envisioned by U.S. jurist Benjamin Cardozo in 1914 regarding the right of individuals to determine medical treatment and participation in medical research. It discusses the study known as SUPPORT conducted by the University of Alabama-Birmingham (UAB) and the related case Fain v. Smith, and also examines the disclosure duties of researchers.

Contact-dependent growth inhibition (CDI) is a widespread mechanism of bacterial competition. CDI+ bacteria deliver the toxic C-terminal region of contact-dependent inhibition A proteins (CdiA-CT) into neighboring target bacteria and produce CDI immunity proteins (CdiI) to protect against self-inhibition. The CdiA-CTEC536 deployed by uropathogenic Escherichia coli 536 (EC536) is a bacterial toxin 28 (Ntox28) domain that only exhibits ribonuclease activity when bound to the cysteine biosynthetic enzyme O-acetylserine sulfhydrylase A (CysK). Here, we present crystal structures of the CysK/CdiA-CTEC536 binary complex and the neutralized ternary complex of CysK/CdiA-CT/CdiIEC536. CdiA-CTEC536 inserts its C-terminal Gly-Tyr-Gly-Ile peptide tail into the active-site cleft of CysK to anchor the interaction. Remarkably, E. coli serine O-acetyltransferase uses a similar Gly-Asp-Gly-Ile motif to form the "cysteine synthase" complex with CysK. The cysteine synthase complex is found throughout bacteria, protozoa, and plants, indicating that CdiA-CTEC536 exploits a highly conserved protein-protein interaction to promote its toxicity. CysK significantly increases CdiA-CTEC536 thermostability and is required for toxin interaction with tRNA substrates. These observations suggest that CysK stabilizes the toxin fold, thereby organizing the nuclease active site for substrate recognition and catalysis. By contrast, Ntox28 domains from Gram-positive bacteria lack C-terminal Gly-Tyr-Gly-Ile motifs, suggesting that they do not interact with CysK. We show that the Ntox28 domain from Ruminococcus lactaris is significantly more thermostable than CdiA-CTEC536, and its intrinsic tRNA-binding properties support CysK-independent nuclease activity. The striking differences between related Ntox28 domains suggest that CDI toxins may be under evolutionary pressure to maintain low global stability. [ABSTRACT FROM AUTHOR]

Tertiary education institutions are currently learning to integrate and balance the needs of varying stakeholders, including local students, national governments, and the global market. These three dimensions combine into the concept of a ‘glonacal’ – global + national + local – region of higher education. At the same time, quality assurance influences higher education in terms of policy decisions and processes, putting more emphasis on teaching as a core function of universities, and leading to an increased bureaucratization and heavier administrative workload. Yet, there is little evidence of the consequences of the glonacal approach for the quality of teaching and learning within universities and colleges. The main purpose of this paper is to assess the impact of the glonacal quality assurance system of Asian higher education through a case study of the effects of three program accreditations on higher education institutions in Taiwan (Higher Education Evaluation & Accreditation Council of Taiwan [HEEACT], Association to Advance Collegiate Schools of Business International [AACSB International] and Institute of Engineering Education Taiwan [IEET]). [ABSTRACT FROM PUBLISHER]

The article describes an activity program for physics education by construction and use of an inexpensive hand-held pneumatic lift to demonstrate relation of air pressure and air pressure difference to force and area.

In an interconnected world, higher education systems, the institutions that comprise them, educational policy makers, quality assurance agencies are all supposed to interact simultaneously in a global, national, and local, or glonacal, context. Like some other Asian nations, Taiwan has been developing its glonacal quality assurance framework. At the same time, it attempted to give more institutional autonomy to universities by awarding them a self-accreditation status. The main purpose of the paper is to examine transformation of QA systems in Taiwan's higher education under the glonacal context and to analyze the new development of self-accreditation. [ABSTRACT FROM AUTHOR]

Volcanic tremor is an important precursor to explosive eruptions and is ubiquitous across most silicic volcanic systems. Oscillations can persist for days and occur in a remarkably narrow frequency band (i.e. 0.5–7 Hz). The recently proposed magma-wagging model of Jellinek & Bercovici provides a basic explanation for the emergence and frequency evolution of tremor that is consistent with observations of many active silicic and andesitic volcanic systems. This model builds on work suggesting that the magma column rising in the volcanic conduit is surrounded by a permeable vesicular annulus of sheared bubbles. The magma-wagging model stipulates that the magma column rattles within the spring like foam of the annulus, and predicts oscillations at the range of observed tremor frequencies for a wide variety of volcanic environments. However, the viscous resistance of the magma column attenuates the oscillations and thus a forcing mechanism is required. Here we provide further development of the magma-wagging model and demonstrate that it implicitly has the requisite forcing to excite wagging behaviour. In particular, the extended model allows for gas flux through the annulus, which interacts with the wagging displacements and induces a Bernoulli effect that amplifies the oscillations. This effect leads to an instability involving growing oscillations at the lower end of the tremor frequency spectrum, and that drives the system against viscous damping of the wagging magma column. The fully non-linear model displays tremor oscillations associated with pulses in gas flux, analogous to observations of audible ‘chugging’. These oscillations also occur in clusters or envelopes that are consistent with observations of sporadic tremor envelopes. The wagging model further accurately predicts that seismic signals on opposite sides of a volcano are out of phase by approximately half a wagging or tremor period. Finally, peaks in gas flux occur at the end of the growing instability several tens of seconds after the largest tremors, which is consistent with observations of a 30- to 50-s lag between major tremor activity and maximum gas release. The extended magma-wagging model, thus, predicts tremor frequency and its evolution before and during an eruption, as well as a driving mechanism to keep the tremor excited for long periods. [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]

Contact-dependent growth inhibition (CDI) systems encode polymorphic toxin/immunity proteins that mediate competition between neighboring bacterial cells. We present crystal structures of CDI toxin/immunity complexes from Escherichia coli EC869 and Burkholderia pseudomallei 1026b. Despite sharing little sequence identity, the toxin domains are structurally similar and have homology to endonucleases. The EC869 toxin is a Zn2+-dependent DNase capable of completely degrading the genomes of target cells, whereas the Bp1026b toxin cleaves the aminoacyl acceptor stems of tRNA molecules. Each immunity protein binds and inactivates its cognate toxin in a unique manner. The EC869 toxin/immunity complex is stabilized through an unusual β-augmentation interaction. In contrast, the Bp1026b immunity protein exploits shape and charge complementarity to occlude the toxin active site. These structures represent the initial glimpse into the CDI toxin/immunity network, illustrating how sequence-diverse toxins adopt convergent folds yet retain distinct binding interactions with cognate immunity proteins. Moreover, we present visual demonstration of CDI toxin delivery into a target cell. [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]

Since the start of the twenty-first century, university rankings have become internationalized. Global rankings have a variety of uses, levels of popularity and rationales and they are here to stay. An examination of the results of the current global ranking reveals that well-reputed world-class universities are amongst the top ranked ones. A major concern for university administrators in many parts of the world is how to use the global rankings wisely in their mid-term and long-term strategic planning for building their institutions into world-class universities. Four major global rankings have been developed: the Academic Ranking of World Universities, the World University Rankings, the Webometrics Ranking of World Universities and the Performance Ranking of Scientific Papers for World Universities. The main purpose of this paper is to explore the most influential indicators in these global university rankings that will affect the rank mobility of an institution. Based on an analysis of correlation coefficients and K-means clustering, a model of strategic institutional planning for building a world-class university is proposed. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis must import iron from its host for survival, and its siderophore-dependent iron acquisition pathways are well established. Here we demonstrate a newly characterized pathway, whereby M. tuberculosis can use free heme and heme from hemoglobin as an iron source. Significantly, we identified the genomic region, Rv0202c-Rv0207c, responsible for the passage of heme iron across the mycobacterial membrane. Key players of this heme uptake system were characterized including a secreted protein and two transmembrane proteins, all three specific to mycobacteria. Furthermore, the crystal structure of the key heme carrier protein Rv0203 was found to have a unique fold. The discovery of a unique mycobacterial heme acquisition pathway opens new avenues of exploration into mycobacterial therapeutics. [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 Ewing’s sarcoma (EWS) protein is a ubiquitously expressed RNA chaperone. The EWS protein localizes predominantly to the nucleus. Previous reports have suggested that the EWS protein is capable of dimerizing. However, to date this has not been confirmed. Here, using a novel panel of recombinant proteins, we have performed an in vitro biomolecular interaction analysis of the EWS protein. We have demonstrated that all three arginine-glycine-glycine (RGG) motifs are capable of binding directly to the survival motor neuron protein, a Tudor domain containing EWS binding partner. We have also confirmed EWS is capable of self-associating, and we have mapped this binding domain to the RGG motifs. We have also found that self-association may be required for EWS nuclear import. This is the first direct evidence of RGG domains being involved in self-association and has implications on all RGG-containing proteins. [ABSTRACT FROM PUBLISHER]

The article discusses the importance of using physically reasonable values in electrostatics. Topics covered include the problems in physical situations in electrostatics, an example of a simple mechanics problem, suggestions for the application of the principle in electrostatics and the need for teachers to be careful in choosing magnitudes of values.

This article aims at identifying a threshold number of drinks per day beyond which there is a high risk of developing alcoholic behavior that would enable physicians to more confidently support the use of alcohol for cardiovascular risk prevention. In a randomly selected, population-based sample of 2,042 adults 45 years or older, we graded alcohol drinking behavior using the Self-Administered Alcoholism Screening Test, quantified alcohol amount by questionnaire, and assessed the prevalence of cardiovascular disease (coronary, peripheral, or cerebrovascular disease) by medical record review. Although optimal alcohol use (≤2 drinks/day) was associated with reduced odds of cardiovascular disease, 43% of alcoholics and 82% of problem drinkers reported alcohol use in the optimal range as well. The association of alcohol use in the optimal range with alcohol-related behavioral problems supports the reluctance in physicians from recommending alcohol use for cardiovascular benefit, not withstanding the underreporting of alcohol use by alcoholics. [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]