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Surface free energy (SFE) is a property which depends on the chemical state and roughness of the surface and it is necessary to develop a reliable method to evaluate SFE value on a small area, taking into account these two different contributions. Today contact angle methods are the most used and they allow to evaluate the global mean value of SFE on areas of mm2 size. With these methods, it is not possible to evaluate the effects of roughness, surface defects, chemical contamination on SFE value. In addition, it is difficult to determine the surface free energy value on small components which have dimensions smaller than drop diameter. Nanoindentation and atomic force microscopy techniques provide alternative direct measurement methods to evaluate the SFE on small areas (on the order of μm2 or nm2) through a contact mechanism triggered by the contact of two bodies. In order to evaluate the adhesion properties, currently three models, Johnson- Kendall-Roberts, Maugis-Dugdale and Derjaguin-Muller-Toporov, use the value of pull-off force (force required to separate the indenter tip from the sample). All influences of surface morphology on SFE values are lost using these methods. In fact the adhesion value obtained refers to the energy balance between two conformal surfaces, which depends mainly on the morphology of the harder material (i.e., diamond tip). In this work we describe a new methodology for the SFE determination consisting in the modeling and quantitative evaluation of the interaction between the tip and sample surface during the approach phase in a nanoindentation test. During the test, the nanoindenter tip is attracted to the sample surface until the sample reaction forces become significant (in this case physical contact between two bodies is achieved). The SFE value is evaluated using experimental force of attraction and displacement of the nanoindenter spherical tip when it approaches the sample surface. In this method the sample surface is not altered by the tip, therefore unlike pull-off force method, it could be very useful to evaluate the actual SFE considering the effect of sample morphology (controlled roughness or pattern). [ABSTRACT FROM AUTHOR]

Strain plays an important role in the performance and reliability of AlGaN/GaN high electron mobility transistors (HEMTs). However, the impact of strain on the performance of proton irradiated GaN HEMTs is yet unknown. In this study, we investigated the effects of strain relaxation on the properties of proton irradiated AlGaN/GaN HEMTs. Controlled strain relief is achieved locally using the substrate micro-trench technique. The strain relieved devices experienced a relatively smaller increase of strain after 5 MeV proton irradiation at a fluence of 5 × 1014 cm−2 compared to the non-strain relieved devices, i.e., the pristine devices. After proton irradiation, both pristine and strain relieved devices demonstrate a reduction of drain saturation current (Ids,sat), maximum transconductance (Gm), carrier density (ns), and mobility (μn). Depending on the bias conditions the pristine devices exhibit up to 32% reduction of Ids,sat, 38% reduction of Gm, 15% reduction of ns, and 48% reduction of μn values. In contrast, the strain relieved devices show only up to 13% reduction of Ids,sat, 11% reduction of Gm, 9% reduction of ns, and 30% reduction of μn values. In addition, the locally strain relieved devices show smaller positive shift of threshold voltage compared to the pristine devices after proton irradiation. The less detrimental impact of proton irradiation on the transport properties of strain relieved devices could be attributed to reduced point defect density producing lower trap center densities, and evolution of lower operation related stresses due to lower initial residual strain. [ABSTRACT FROM AUTHOR]

The coatings of ZrN, (Zr,Ti)N, (Ti,Zr,Hf)N and (Ti,Zr,Nb)N deposited on the titanium alloy substrate were compared. The wear resistance in the pin-on-disk test together with the Al2O3 indenter and the corrosion resistance in 3.5% NaCl solution were studied. It was found that the (Zr,Nb,Ti)N coating has the best resistance to wear, but has low corrosion resistance. The (Ti,Zr,Hf)N coating, on the contrary, has the best corrosion resistance, but low resistance to wear. The ZrN coating has good corrosion resistance combined with good resistance to wear. This coating is best suited for use in friction conditions with a ceramic counterbody under the influence of seawater. An important resource for increasing the properties of coatings is increasing their adhesion to the substrate, which can be achieved in two combined ways: (1) complete removal of the original oxide layer from the surface of the substrate and (2) the use of optimal compositions of the adhesive sublayer, which have not only high adhesive properties in relation to both the substrate and the coating, but also high strength. While the introduction of Nb into the ZrN coating composition increases wear resistance and the introduction of Hf increases corrosion resistance, the ZrN coating without additives best resists wear and corrosion simultaneously. [ABSTRACT FROM AUTHOR]

This study demonstrates that bond strength can be enhanced by injecting excess electrons or holes into a material by electron beam irradiation. To determine the effect of excess electrons/holes on the interatomic bond strength, fracture toughness tests were performed on single-crystal Si micropillars under various electron-beam irradiation conditions. The fracture toughness under electron beam irradiation was 4%–11% higher than that under non-irradiated conditions. In particular, an increase in strength was large in tests performed under hole-injection conditions. Furthermore, in first-principles calculations of the tensile strength of excess electrons/hole-doped Si, the ideal tensile strength monotonically decreased with an injection in excess electrons and increased monotonically with the injection of holes. This is qualitatively consistent with the experimental result that the fracture toughness increases under hole-injection conditions. [ABSTRACT FROM AUTHOR]

In recent decades, much work has been implemented in heart rate (HR) analysis using electrocardiographic (ECG) signals. We propose that algorithms developed to calculate HR based on detected R-peaks using ECG can be applied to seismocardiographic (SCG) signals, as they utilize common knowledge regarding heart rhythm and its underlying physiology. We implemented the experimental framework with methods developed for ECG signal processing and peak detection to be applied and evaluated on SCGs. Furthermore, we assessed and chose the best from all combinations of 15 peak detection and 6 preprocessing methods from the literature on the CEBS dataset available on Physionet. We then collected experimental data in the lab experiment to measure the applicability of the best-selected technique to the real-world data; the abovementioned method showed high precision for signals recorded during sitting rest (HR difference between SCG and ECG: 0.12 ± 0.35 bpm) and a moderate precision for signals recorded with interfering physical activity—reading out a book loud (HR difference between SCG and ECG: 6.45 ± 3.01 bpm) when compared to the results derived from the state-of-the-art photoplethysmographic (PPG) methods described in the literature. The study shows that computationally simple preprocessing and peak detection techniques initially developed for ECG could be utilized as the basis for HR detection on SCG, although they can be further improved. [ABSTRACT FROM AUTHOR]

Background: There are many problems of psychological burden in patients with tumor implanted in port of intravenous infusion. However, more attention is paid to its complications in the literature, and psychological problems are seldom concerned. The purpose of this study was to explore the psychological state and needs of tumor patients after implantation of an intravenous infusion port and provide valuable references for psychological interventions. Method: A semi-structured interview was conducted with 11 patients with intravenous infusion ports. Colaizzi's 7-step analysis was used to analyze the interview data. Results: According to the primary information, four themes and nine sub-themes were extracted: (1) lack of self-worth, (2) multiple emotional experiences (guilt, doubt, worry, and gain). (3) Poor self-management and self-maintenance awareness (over-reliance on medical staff, unchanged family roles, lack of related knowledge). (4) Expectations and suggestions for the future (inner expectations, suggestions for infusion ports). Conclusion: The patient's psychological state should be carefully monitored during tube implantation, to relieve the patient's tension and anxiety and improve nursing satisfaction and patient outcomes. [ABSTRACT FROM AUTHOR]

Training and expertise in regional anaesthesia have increased significantly in tandem with increased interest over the past two decades. This review outlines the most recent advances in regional anaesthesia and focuses on novel areas of interest including fascial plane blocks. Pharmacological advances in the form of the prolongation of drug duration with liposomal bupivacaine are considered. Neuromodulation in the context of regional anaesthesia is outlined as a potential future direction. The growing use of regional anaesthesia outside of the theatre environment and current thinking on managing the rebound plane after regional block regression are also discussed. Recent relevant evidence is summarised, unanswered questions are outlined, and priorities for ongoing investigation are suggested. [ABSTRACT FROM AUTHOR]

Analysis of the sliding wear and microstructural characteristics of iron based composite coatings are discussed. The feedstock, which consisted of 30% SiC and 70% FeNiCrMo, was mechanically combined using a ball milling process. A steel substrate made of ASTM-SA213-T11 was then sprayed with the prepared feedstock using the High Velocity Oxy Fuel (HVOF) process. The coating and substrate were put through a sliding test using a pin-on disc tribometer while being subjected to typical loads of 10 and 20 N at 200°C and 300°C as well as ambient conditions without lubrication. The samples were subjected to microstructures and phase studies using SEM and XRD techniques. Wear characteristics including friction coefficient, volumetric material loss, and wear rates of the coating and substrate were calculated using system-produced data. The hardness and wear resistance of the coated samples were improved owing to the coating region containing hard carbide phases such as SiC and Fe2C. [ABSTRACT FROM AUTHOR]

In this work, we first review the previous work done on statistical nanoindentation by different researchers, highlighting the main problems that have been found and possible proposed solutions. In the second part, we study and report the statistical nanoindentation of three model samples, in the form of a soft Al2124 matrix embedded with hard SiC particles. Three different variants were selected: (1) 25% of SiC particles with 3 μm diameter; (2) 25% of SiC particles with 0.7 μm diameter; and (3) 17% of SiC particles with 0.3 μm diameter. We propose a novel heuristic wavelet technique to filter the measurement noise from the raw nanoindentation data as an attempt to obtain a more robust statistical nanoindentation methodology. Our results have shown that, when the nanoindentation data are filtered, it is not necessary to select a priori the number of peaks (phases) to be analyzed and, in some cases, a wide number of bin-sizes can be used without affecting the results. Finally, a finite element modeling have been used to analyze the response of the nanoindenter regarding the position of the hard particle. Our model shows that it is impossible to get the whole hardness value of the hard SiC particle by the statistical nanoindentation methodology. [ABSTRACT FROM AUTHOR]

(V,Mo)N is theoretically predicted to have high hardness and fracture toughness and is a promising material for the application on protective hard coatings. However, the toughness enhancement of (V,Mo)N coatings deposited by dc-unbalanced magnetron sputtering (dc-UBMS) was not as remarkable as expected. The issue could be due to insufficient energy delivery to the plasma species in the deposition process such that nitrogen and metal atoms were not fully reacted and led to the degradation of coating quality. Since high-power pulsed magnetron sputtering (HPPMS) can provide high peak power density, the method was selected to deposit (V,Mo)N coatings in this research. The objective of this study was to investigate the effects of duty cycle and nitrogen flow rate on the microstructure and mechanical properties of (V,Mo)N coatings deposited on Si substrates by HPPMS. Four sets of (V,Mo)N coatings were deposited by HPPMS at different durations with two duty cycles, 5% and 3%, and two nitrogen flow rates, 6.0 and 12.0 SCCM. The results showed that the N/metal ratio was mainly affected by the nitrogen flow rate, ranging from 0.70 to 0.96 with increasing nitrogen flow rate. The lattice parameter of the samples linearly increased with the N/metal ratio. The x-ray diffraction (XRD) patterns revealed that all samples tended to approach (200)-preferred orientation with increasing deposition duration. The glancing incident XRD patterns indicated that the samples deposited at 6 SCCM nitrogen flow rate and 3% duty cycle have multiphases. Transmission electron microscopy analysis confirmed that phase separation from (V,Mo)N to (V-rich,Mo)N and (V,Mo-rich)N occurred in those samples. The hardness of the (V,Mo)N coatings decreased with increasing N/metal ratio, which may be related to the N-vacancy hardening effect. The sample deposited at 6 SCCM nitrogen flow rate and 3% duty cycle for 36 h showed the highest hardness of 28.4 GPa, which was possibly associated with the phase separation, and hence plastic deformation became difficult. The fracture toughness (Gc) of the (V,Mo)N coatings was evaluated using the internal energy-induced cracking method. The resultant Gc of the (V,Mo)N coatings, ranging from 36.1 to 43.7 J/m2, was higher than that of the coatings deposited by dc-UBMS in our previous study. The toughness enhancement could be caused by a higher fraction of Mo–N bonding due to the adequate reaction energy provided by the HPPMS process. [ABSTRACT FROM AUTHOR]

In this work, functionally graded material (FGM) coating that uses three powders with WC-10 wt% Co-4 wt% Cr (designated as P1), WC-12 wt% Co (designated as P2), and Ni-25 wt% Cr (designated as P3) are proposed for use over the liners of CI engines. Scanning electron microscopy and energy dispersive x-ray spectroscopy are conducted to analyze the microstructural properties, composition, and quality of the powder and the prepared coating. Results shows that the porosity of powder P3 is the highest of all three powders used in this work, and the porosity of powder P2 is smallest, whereas the porosity of powder P1 lies between P1 and P3. In addition, the hardness of the FGM coating, measured using Vicker's test, containing a combination of P1 and P2 (designated as sample 1), is higher than that of the FGM prepared with a combination of P2, P3 and P1, P3. The findings of the present work have potential implications for improving the performance and durability of CI engine liners by using an appropriate FGM coating. [ABSTRACT FROM AUTHOR]

Introduction: Surgical procedures, even under local anesthesia, can induce significant stress and anxiety in patients. Innovative approaches to alleviate anxiety are crucial for improving patient outcomes. Sedatives and anxiolytics may alleviate this discomfort, but they can also subject patients to undesirable side effects, diminishing their overall effectiveness, and, finally, delaying discharge. We present the first case series of a patients underwent inguinal hernia surgical repair under local anesthesia using VRH (HypnoVR) to avoid use of sedatives and anxiolytics., Methods: 12 consecutive patients were enrolled to undergo elective monolateral inguinal hernia repair surgery via an open approach using HypnoVR, at Colorectal Surgery Unit of Fondazione Policlinico Universitario Campus Bio-Medico di Roma. Vital signs (heart rate, SpO2, blood pressure) were detected for all patients before surgery, during local anesthesia, during the whole intervention and after surgery., Results: No intraoperative or postoperative complications have been recorded and only one postoperative complication occurred (seroma), which not required invasive treatment but only drug administration. All patient's vital parameters were recorded during all operative and perioperative phasis. No use of intraoperative analgesic, sedative or anxiolytic were needed. All patients were discharged no later than 3 h after surgery., Conclusion: Virtual Reality Hypnosis is a promising tool for anxiety management in surgical settings. Our series highlights the positive impact of HypnoVR in reduction and management of surgical patient anxiety and discomfort, allowing to perform inguinal hernia repair using only local anesthesia, with good patients' satisfaction., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Cardio-mechanical monitoring techniques, such as Seismocardiography (SCG) and Gyrocardiography (GCG), have received an ever-growing interest in recent years as potential alternatives to Electrocardiography (ECG) for heart rate monitoring. Wearable SCG and GCG devices based on lightweight accelerometers and gyroscopes are particularly appealing for continuous, long-term monitoring of heart rate and its variability (HRV). Heartbeat detection in cardio-mechanical signals is usually performed with the support of a concurrent ECG lead, which, however, limits their applicability in standalone cardio-mechanical monitoring applications. The complex and variable morphology of SCG and GCG signals makes the ECG-free heartbeat detection task quite challenging; therefore, only a few methods have been proposed. Very recently, a template matching method based on normalized cross-correlation (NCC) has been demonstrated to provide very accurate detection of heartbeats and estimation of inter-beat intervals in SCG and GCG signals of pathological subjects. In this study, the accuracy of HRV indices obtained with this template matching method is evaluated by comparison with ECG. Tests were performed on two public datasets of SCG and GCG signals from healthy and pathological subjects. Linear regression, correlation, and Bland-Altman analyses were carried out to evaluate the agreement of 24 HRV indices obtained from SCG and GCG signals with those obtained from ECG signals, simultaneously acquired from the same subjects. The results of this study show that the NCC-based template matching method allowed estimating HRV indices from SCG and GCG signals of healthy subjects with acceptable accuracy. On healthy subjects, the relative errors on time-domain indices ranged from 0.25% to 15%, on frequency-domain indices ranged from 10% to 20%, and on non-linear indices were within 8%. The estimates obtained on signals from pathological subjects were affected by larger errors. Overall, GCG provided slightly better performances as compared to SCG, both on healthy and pathological subjects. These findings provide, for the first time, clear evidence that monitoring HRV via SCG and GCG sensors without concurrent ECG is feasible with the NCC-based template matching method for heartbeat detection. [ABSTRACT FROM AUTHOR]

Background: The immediate postoperative period after total hip arthroplasty can be associated with significant pain. Therefore, this study aimed to evaluate the effect of pericapsular nerve block on pain management and functional recovery after total hip arthroplasty. Methods: This prospective, randomized, double-blinded, placebo-controlled trial was conducted on 489 adult patients scheduled for total hip arthroplasty, ASA 1–2, operated under spinal analgesia. Participants were assigned to receive either a pericapsular nerve group (PENG) block with 20 mL of 0.5% ropivacaine or a sham block. Results: The primary outcome measure was the postoperative NRS score in motion. The secondary outcomes were cumulative opioid consumption, the time to the first opioid, and functional recovery. Demographic characteristics were similar in both groups. Intraoperative pain scores were significantly lower in patients who received the PENG block than in the control group (p < 0.0001). Also, the time to the first opioid was considerably longer in the PENG group (p < 0.0001). Additionally, 24% of PENG patients did not require opioids (p < 0.0001). Conclusions: The pericapsular nerve group showed significantly decreased opioid consumption and improved functional recovery. Pericapsular nerve group block improved pain management and postoperative functional recovery following total hip arthroplasty. [ABSTRACT FROM AUTHOR]

The structural stability and durability of a sensing device at high‐temperatures (HT) have important effects on its functionality and reliability. This becomes more critical in the devices that work based on the surface acoustic waves (SAW). In this study, the thermomechanical and creep behaviors of the metallization systems, RuAl, MoLa, and Mo suggested for the electrodes of HT‐SAW sensors are investigated. Several experiments are designed to obtain the state and the value of stress in the films deposited on a Si [100] substrate caused by the fabrication process and the operational conditions. Results show that after the film deposition, the intrinsic compressive stress in the MoLa film is significantly lower than the other films. However, after annealing the samples, the lowest residual stress is reached in the Mo. Linear stress variations during the thermal cycling of the annealed samples are obtained for all metallizations. To study the durability of the films at HT, the creep behavior of the samples is investigated by keeping them at a temperature of 600 °C for 10 h. The creep rate and its constitutive equation for the films are obtained. It is observed that the creep rate of MoLa and Mo films is much lower than RuAl. [ABSTRACT FROM AUTHOR]

Thermal spraying is a broad terminology for a coating process in which materials are deposited in a spray of finely distributed liquefied or semi-liquefied particulates to build layered deposition coatings. Duplex and composite coatings can be utilized in the thermal spray technique to enhance the tribological properties of a broad range of engineering materials while saving money; service life extension, maintenance expenses, and replacement costs are lower than for single-layered coatings. As a result, this paper critically analyses various pre-processing surface treatments for substrates, commonly used thermal spray processing methods, and various post-processing surface treatments for thermally sprayed substrate materials. This paper also includes a description of several characterization methodologies as well as some comprehensive prospective applications for engineering components with challenges and scopes. Thus, this paper provides a fundamental understanding of surface treatments to researchers who use thermal spray coating techniques. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are beneficial in various applications such as gas separation, catalysis, wastewater treatment, and dye removal. The current study proposes a novel approach to the use of the zeolitic imidazolate framework (ZIF-67), a subfamily of MOFs, in cement composites. ZIF-67 nanoparticles were synthesized in the laboratory and analyzed using X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscope (TEM). ZIF-67 nanocrystals were incorporated in the cement matrix at a concentration of 0.3%, 0.4%, 0.5%, and 0.6% by weight of cement. The influence of ZIF-67 nanoparticles on the workability, mechanical strength, and microstructure was thoroughly investigated. The workability of cement paste was hindered by the addition of ZIF-67. The compressive strength of ZIF-67 cement composites was enhanced by 27.81% at 3 days and 20.36% at 28 days. This was attributed to the densification of microstructure. The optimum content of ZIF-67 in cement composites among the selected concentrations was determined to be 0.6% by weight of cement. The microstructure images revealed the pore-filling mechanism of ZIF-67 in cement composition as well as in providing additional nuclei sites for the hydration products. It was concluded that ZIF-67 nanoparticles act as a nonreactive filler in cement composites. There exists a huge potential for use of ZIFs in cement composites, which is yet to be explored. [ABSTRACT FROM AUTHOR]

This work studied the effect of alkali activated slag-fly ash (AASFA) material on the adhesive interface mechanical properties and chloride permeability of repaired ordinary concrete. The splitting tensile strength and chloride diffusion coefficient of the bonding surface repaired using three methods were compared: direct repair of ordinary concrete (method I), surface agents of cementitious slurry and alkaline activated slag-fly ash slurry followed by repair with ordinary concrete (method II), and direct repair with alkaline activated slag-fly ash concrete (method III). The microstructure including pore size distribution and micro-morphology of adhesive interface were investigated systematically. The results showed that the effect of direct repairing with AASFA concrete was the best among the three repairing methods. In this case, the reasonable modulus of the alkali activator was 1.3, and the adoptable slag content was 50%. The splitting tensile strength of the new-to-old concrete prepared by method II increased first with the increase in slag content and then decreased. There was a good linear correlation between the pore tortuosity and the chloride diffusion coefficient, and the chloride penetration resistance was mainly affected by pore tortuosity. For AASFA as the repairing material, the bonding strength of new-to-old concrete was not only dominated by pore structure but also affected by chemical reaction. The large amount of C-(A)-S-H gel generated at the adhesive interface not only filled the pores of the bonding surface but also provided additional bonding strength. [ABSTRACT FROM AUTHOR]

Background: Patient education information material (PEIM) is an essential component of patient education programs in increasing patients' ability to cope with their diseases. Therefore, it is essential to consider the criteria that will be used to prepare and evaluate these resources. Objective: This paper aims to identify these criteria and recognize the tools or methods used to evaluate them. Methods: National and international databases and indexing banks, including PubMed, Scopus, Web of Science, ProQuest, the Cochrane Library, Magiran, SID and ISC, were searched for this review. Original or review articles, theses, short surveys, and conference papers published between January 1990 and June 2022 were included. Results: Overall, 4688 documents were retrieved, of which 298 documents met the inclusion criteria. The criteria were grouped into 24 overarching criteria. The most frequently used criteria were readability, quality, suitability, comprehensibility and understandability. Conclusion: This review has provided empirical evidence to identify criteria, tools, techniques or methods for developing or evaluating a PEIM. The authors suggest that developing a comprehensive tool based on these findings is critical for evaluating the overall efficiency of PEIM using effective criteria. [ABSTRACT FROM AUTHOR]

Heart rate variability (HRV) is the physiological variation in the intervals between consecutive heartbeats that reflects the activity of the autonomic nervous system. This parameter is traditionally evaluated based on electrocardiograms (ECG signals). Seismocardiography (SCG) and/or gyrocardiography (GCG) are used to monitor cardiac mechanical activity; therefore, they may be used in HRV analysis and the evaluation of valvular heart diseases (VHDs) simultaneously. The purpose of this study was to compare the time domain, frequency domain and nonlinear HRV indices obtained from electrocardiograms, seismocardiograms (SCG signals) and gyrocardiograms (GCG signals) in healthy volunteers and patients with valvular heart diseases. An analysis of the time domain, frequency domain and nonlinear heart rate variability was conducted on electrocardiograms and gyrocardiograms registered from 29 healthy male volunteers and 30 patients with valvular heart diseases admitted to the Columbia University Medical Center (New York City, NY, USA). The results of the HRV analysis show a strong linear correlation with the HRV indices calculated from the ECG, SCG and GCG signals and prove the feasibility and reliability of HRV analysis despite the influence of VHDs on the SCG and GCG waveforms. [ABSTRACT FROM AUTHOR]

Surgery for vestibular schwannoma includes various techniques such as the middle cranial fossa, suboccipital, translabyrinthine, and retrolabyrinthine approaches. The retrolabyrinthine approach does not impair the labyrinth and allows postoperative hearing preservation. Previously, we reported an endoscope-assisted retrolabyrinthine approach under reinforced continuous intraoperative monitoring for preservation of hearing and facial nerve function. However, the hearing preservation rate was relatively low in patients with long-wave V latency in the auditory brainstem response or poor otoacoustic emission response under this approach. Thus, the hearing preservation rate in such patients remains to be improved. To overcome this limitation, we modified the previous approach. In 26 of the 33 consecutive cases (79%) over the last three years, preservation of hearing equivalent to that before surgery or improved hearing was achieved. Postoperative deafness was observed in only two of the 33 cases (6%). According to previous reports, the rate of hearing preservation using the retrolabyrinthine approach is approximately 30–50%. Therefore, we have achieved a higher hearing preservation rate than that previously reported using the endoscopy-assisted retrolabyrinthine approach under reinforced continuous intraoperative monitoring. These improvements in our department are considered to be helpful for hearing preservation. [ABSTRACT FROM AUTHOR]

The sensitivity of a low-noise superconducting transition edge sensor (TES) is determined by the thermal conductance of the support structure that connects the active elements of the device to the heat bath. Low-noise devices require conductances in the range 0.1 to 10 pW K − 1 and so have to rely on diffusive phonon scattering in long, narrow, amorphous SiN x legs. We show that it is possible to manufacture and operate TESs having short, ballistic low-dimensional legs (cross section 0.5 × 0.2 μ m) that contain multi-element phononic interferometers and ring resonators. These legs transport heat in effectively just 5 elastic modes at the TES's operating temperature (< 150 mK), which is close to the quantised limit of 4. The phononic filters then reduce the thermal flux further by frequency-domain filtering. For example, a micromachined 3-element ring resonator reduced the flux to 19% of a straight-legged ballistic device operating at the quantised limit and 38% of a straight-legged diffusive reference device. This work opens the way to manufacturing TESs where performance is determined entirely by filtered, few-mode, ballistic thermal transport in short, low-heat capacity legs, free from the artifacts of two level systems. [ABSTRACT FROM AUTHOR]