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The coercive field of permanent magnets decays with temperature. At non-zero temperatures, the system can overcome a finite energy barrier through thermal fluctuations. Using finite element micromagnetic simulations, we quantify this effect, which reduces coercivity in addition to the decrease of the coercive field associated with the temperature dependence of the anisotropy field, and validate the method through comparison with existing experimental data.

The rare-earth crisis, which peaked in the summer of 2011 with the prices of both light and heavy rare earths soaring to unprecedented levels, brought about the widespread realization that the long-term availability and price stability of rare earths could not be guaranteed. This triggered a rapid response from manufacturers involved in rare earths, as well as governments and national and international funding agencies. In the case of rare-earth-containing permanent magnets, three possibilities were given quick and serious consideration: (I) increased recycling of devices containing rare earths; (II) the search for new, mineable, rare-earth resources beyond those in China; and (III) the development of high-energy-product permanent magnets with little or no rare-earth content used in their manufacture. The Replacement and Original Magnet Engineering Options (ROMEO) project addresses the latter challenge using a two-pronged approach. With its basis on work packages that include materials modeling and advanced characterization, the ROMEO project is an attempt to develop a new class of novel permanent magnets that are free of rare earths. Furthermore, the project aims to minimize rare-earth content, particularly heavy-rare-earth (HRE) content, as much as possible in Nd-Fe-B-type magnets. Success has been achieved on both fronts. In terms of new, rare-earth-free magnets, a Heusler alloy database of 236,945 compounds has been narrowed down to approximately 20 new compounds. Of these compounds, Co 2 MnTi is expected to be a ferromagnet with a high Curie temperature and a high magnetic moment. Regarding the reduction in the amount of rare earths, and more specifically HREs, major progress is seen in electrophoretic deposition as a method for accurately positioning the HRE on the surface prior to its diffusion into the microstructure. This locally increases the coercivity of the rather small Nd-Fe-B-type magnet, thereby substantially reducing the dependence on the HREs Dy and Tb, two of the most critical raw materials identified by the European Commission. Overall, the ROMEO project has demonstrated that rapid progress can be achieved when experts in a specific area are brought together to focus on a particular challenge. With more than half a year of the ROMEO project remaining, further progress and additional breakthroughs can be expected.

There are several limitations to this study. Firstly, one may have difficulty in observing \"Western\" or \"Sikh\" as separate counterparts, considering that cultures and religions are not homogeneous blocks of similar values. We do not declare that the Sikh group is uninfluenced by Western traditions in Canada, but we are attempting to analyse the attitudes we observed through the eyes of individuals who have devout Sikh values.

A fully-automated pole-tip shape optimization tool, involving write head geometry construction, meshing, micromagnetic simulation and evaluation, is presented. Optimizations have been performed for three different writing schemes (centered, staggered and shingled) for an underlying bit patterned media with an areal density of 2.12 Tdots/in\\(^2\\) . Optimizations were performed for a single-phase media with 10 nm thickness and a mag spacing of 8 nm. From the computed write field and its gradient and the minimum energy barrier during writing for islands on the adjacent track, the overall write error rate is computed. The overall write errors are 0.7, 0.08, and 2.8 x 10\\(^{-5}\\) for centered writing, staggered writing, and shingled writing.

Based on a critical analysis of the experimental coercive properties, general considerations on the reversal mechanisms in RFeB magnets are recalled. By plotting together the experimental parameters obtained in various magnets, common features of the reversal processes are demonstrated. Modeling provides an almost quantitative description of coercivity in these materials and permits connecting the defect characteristic properties to reversal mechanisms.

We perform a qualitative analysis of phase locking in a double point-contact spinvalve system by solving the Landau-Lifshitz-Gilbert-Slonzewski equation using a hybrid-finite-element method. We show that the phase-locking behaviour depends on the applied field angle. Starting from a low field angle, the locking-current difference between the current through contact A and B increases with increasing angle up to a maximum of 14 mA at 30 degree and it decreases thereafter until it reaches a minimum of 1 mA at 75 degree. The tunability of the phase-lock frequency with current decreases linearly with increasing out of plane angle from 45 to 21 MHz/mA.

Eustachian tube dysfunction (ETD) is a commonly diagnosed disorder of Eustachian tube opening and closure, which may be associated with severe symptoms and middle ear disease. Currently the diagnosis of obstructive and patulous forms of ETD is primarily based on non-specific symptoms or examination findings, rather than measurement of the underlying function of the Eustachian tube. This has proved problematic when selecting patients for treatment, and when designing trial inclusion criteria and outcomes. This study aims to determine the correlation and diagnostic value of various tests of ET opening and patient reported outcome measures (PROMs), in order to generate a recommended diagnostic pathway for ETD. Index tests included two PROMs and 14 tests of ET opening (nine for obstructive, five for patulous ETD). In the absence of an accepted reference standard two methods were adopted to establish index test accuracy: expert panel diagnosis and latent class analysis. Index test results were assessed with Pearson correlation and principle component analysis, and test accuracy was determined. Logistic regression models assessed the predictive value of grouped test results. The expert panel diagnosis and PROMs results correlated with each other, but not with ET function measured by tests of ET opening. All index tests were found to be feasible in clinic, and acceptable to patients. PROMs had very poor specificity, and no diagnostic value. Combining the results of tests of ET function appeared beneficial. The latent class model suggested tympanometry, sonotubometry and tubomanometry have the best diagnostic performance for obstructive ETD, and these are included in a proposed diagnostic pathway. ETD should be diagnosed on the basis of clinical assessment and tests of ET opening, as PROMs have no diagnostic value. Currently diagnostic uncertainty exists for some patients who appear to have intermittent ETD clinically, but have negative index test results.

Extrusion of electrodes outside the cochlea and tip fold overs may lead to suboptimal outcomes in cochlear implant (CI) recipients. Intraoperative measures such as Trans-Impedance Matrix (TIM) measurements may enable clinicians to identify electrode malposition and direct surgeons to correctly place the electrode array during surgery. To assess the current literature on the effectiveness of TIM measurements in identifying extracochlear electrodes and tip fold overs. A scoping review of studies on TIM-based measurements were carried out using the Databases-Medline/PubMed, AMED, EMBASE, CINAHL and the Cochrane Library following PRISMA guidelines. Eleven full texts articles met the inclusion criteria. Only human studies pertaining to TIM as a tool used in CI were included in the review. Further, patient characteristics, electrode design, and TIM measurement outcomes were reported. TIM measurements were available for 550 implanted ears with the subjects age ranged between 9 months to 89 years. Abnormal TIM measurements were reported for 6.55% (36). Tip fold over was detected in 3.64% (20) of the cases, extracochlear electrodes in 1.45% (8), and 1.45% (8) were reported as buckling. Slim-modiolar electrode array designs were more common (54.71%) than pre-curved (23.34%) or lateral wall (21.95%) electrode array. Abnormal cochlear anatomy was reported for five ears (0.89%), with normal cochlear anatomy for all other patients. TIM measurement is a promising tool for the intraoperative detection of electrode malposition. TIM measurement has a potential to replace intraoperative imaging in future. Though, TIM measurement is in its early stages of clinical utility, intuitive normative data sets coupled with standardised criteria for detection of abnormal electrode positioning would enhance its sensitivity.

Cochlear implants (CI) with off-the-ear (OTE) and behind-the-ear (BTE) speech processors differ in user experience and audiological performance, impacting speech perception, comfort, and satisfaction. This systematic review explores audiological outcomes (speech perception in quiet and noise) and non-audiological factors (device handling, comfort, cosmetics, overall satisfaction) of OTE and BTE speech processors in CI recipients. We conducted a systematic review following PRISMA-S guidelines, examining Medline, Embase, Cochrane Library, Scopus, and ProQuest Dissertations and Theses. Data encompassed recipient characteristics, processor usage, speech perception, and non-audiological factors. Studies were assessed for quality and risk of bias by using Newcastle-Ottawa Scale (NOS). Nine studies involving 204 CI recipients, with a mean age of 49.01 years and 6.62 years of processor use, were included. Audiological results indicated comparable performance in quiet environments, with a slight preference for OTE in noisy conditions. For non-audiological factors, OTE processors excelled in comfort, handling, and aesthetics, leading to higher satisfaction. More data on medical complications and long-term implications is needed. OTE processors may offer comparable performance to BTE processors in certain conditions, though not universally across all audiological outcomes. Interpretation depends on settings, processor generation, and testing paradigms. However, non-audiological factors might favour OTE. Understanding current literature may guide professionals in selecting suitable processors for CI recipients.

Complex walking tasks such as turning or walking with head movements are frequently used to assess dysfunction in an individual’s vestibular, nervous and musculoskeletal systems. Compared to other methods, wearable inertial measurement units (IMUs) allow quantitative analysis of these tasks in less restricted settings, allowing for a more scalable clinical measurement tool with better ecological validity. This study investigates the use of ear-worn IMUs to identify gait events during complex walking tasks, having collected data on 68 participants with a diverse range of ages and movement-related conditions. The performance of an existing gait event detection algorithm was compared with a new one designed to be more robust to lateral head movements. Our analysis suggests that while both algorithms achieve high initial contact sensitivity across all walking tasks, our new algorithm attains higher terminal contact sensitivity for turning and walking with horizontal head turns, resulting in more accurate estimates of stance and swing times. This provides scope to enable more detailed assessment of complex walking tasks during clinical testing and in daily life settings.