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Bioelectronic patches hold promise for patient-comfort wound healing providing simplified clinical operation. Currently, they face paramount challenges in establishing long-term effective electronic interfaces with targeted cells and tissues due to the inconsistent energy output and high bio interface impedance. Here a new electrochemical stimulation technology is reported, using a simple wound patch, which integrates the efficient generation and delivery of stimulation. This is realized by employing a hydrogel bioelectronic interface as an active component in an integrated power source (i.e., Mg battery). The Mg battery enhances fibroblast functions (proliferation, migration, and growth factor secretion) and regulates macrophage phenotype (promoting regenerative polarization and down-regulating pro-inflammatory cytokines), by providing an electric field and the ability to control the cellular microenvironment through chemical release. This bioelectronic patch shows an effective and accelerated wound closure by guiding epithelial migration, mediating immune response, and promoting vasculogenesis. This new electrochemical-mediated therapy may provide a new avenue for user-friendly wound management as well as a platform for fundamental insights into cell stimulation.

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Two-dimensional (2D) materials are promising for resistive switching in neuromorphic and in-memory computing, as their atomic thickness substantially improve the energetic budget of the device and circuits. However, many 2D resistive switching materials struggle with complex growth methods or limited scalability. 2D tellurium exhibits striking characteristics such as simplicity in chemistry, structure, and synthesis making it suitable for various applications. This study reports the first memristor design based on nanoscaled tellurium synthesized by vapor transport deposition (VTD) at a temperature as low as 100 °C fully compatible with back-end-of-line processing. The resistive switching behavior of tellurium nanosheets is studied by conductive atomic force microscopy, providing valuable insights into its memristive functionality, supported by microscale device measurements. Selecting gold as the substrate material enhances the memristive behavior of nanoscaled tellurium in terms of reduced values of set voltage and energy consumption. In addition, formation of conductive paths leading to resistive switching behavior on the gold substrate is driven by gold-tellurium interface reconfiguration during the VTD process as revealed by energy electron loss spectroscopy analysis. These findings reveal the potential of nanoscaled tellurium as a versatile and scalable material for neuromorphic computing and underscore the influential role of gold electrodes in enhancing its memristive performance.

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Precise deposition of metal-organic framework (MOF) materials is important for fabricating high-performing MOF-based devices. Electric-field assisted drop-casting of poly(3,4-ethylenedioxythiophene)-functionalized (PEDOT) MIL-101(Cr) nanoparticles onto interdigitated electrodes allowed their precise spatioselective deposition as percolating nanoparticle chains in the interelectrode gaps. The resulting aligned materials were investigated for resistive and capacitive humidity sensing and compared with unaligned samples prepared via regular drop-casting. The spatioselective deposition of MOFs resulted in up to over 500 times improved conductivity and approximately 6 times increased responsivity during resistive humidity sensing. The aligned samples also showed good capacitive humidity sensing performance, with up to 310 times capacitance gain at 10 versus 90 % relative humidity. In contrast, the resistive behavior of the unaligned samples rendered them unsuitable for capacitive sensing. This work demonstrates that applying an alternating potential during drop-casting is a simple yet effective method to control MOF deposition for greater efficiency, conductivity, and enhanced humidity sensing performance.

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The conventional real-time screening in organs-on-chips is limited to optical tracking of pre-tagged cells and biological agents. This work introduces an efficient biofabrication protocol to integrate tunable hydrogel electrodes into 3D bioprinted-on-chips. We established our method of fabricating cell-laden hydrogel-based microfluidic chips through digital light processing-based 3D bioprinting. Our conductive ink includes poly-(3,4-ethylene-dioxythiophene)-polystyrene sulfonate (PEDOT: PSS) microparticles doped in polyethylene glycol diacrylate (PEGDA). We optimized the manufacturing process of PEDOT: PSS microparticles characterized our conductive ink for different 3D bioprinting parameters, geometries, and materials conditions. While the literature is limited to 0.5% w/v for PEDOT: PSS microparticle concentration, we increased their concentration to 5% w/v with superior biological responses. We measured the conductivity in the 3-15 m/m for a range of 0.5%-5% w/v microparticles, and we showed the effectiveness of 3D-printed electrodes for predicting cell responses when encapsulated in gelatin-methacryloyl (GelMA). Interestingly, a higher cellular activity was observed in the case of 5% w/v microparticles compared to 0.5% w/v microparticles. Electrochemical impedance spectroscopy measurements indicated significant differences in cell densities and spheroid sizes embedded in GelMA microtissues.

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Conductive atomic force microscopy (CAFM) analyzes electronic phenomena in materials and devices with nanoscale lateral resolution, and it is widely used by companies, research institutions, and universities. Most data published in the field of CAFM is collected in air at a relative humidity (RH) of 30-60%. However, the effect of RH in CAFM remains unclear because previous studies often made contradictory claims, plus the number of samples and locations tested is scarce. Moreover, previous studies on this topic did not apply current limitations, which can degrade the CAFM tips and generate false data. This article systematically analyzes the effect of RH in CAFM by applying ramped voltage stresses at over 17,000 locations on ten different samples (insulating, semiconducting, and conducting) under seven different RH. An ultra-reliable setup with a 110-pA current limitation during electrical stresses is employed, and excellent CAFM tip integrity after thousands of tests is demonstrated. It is found that higher RH results in increased currents due to the presence of a conductive water meniscus at the tip/sample junction, which increases the effective area for electron flow. This trend is observed in insulators and ultra-thin semiconductors; however, in thicker semiconductors the electron mean free path is high enough to mask this effect. Metallic samples show no dependence on RH. This study clarifies the effect of relative humidity in CAFM, enhances understanding of the technique, and teaches researchers how to improve the reliability of their studies in this field.

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We present a new simple approach for electrochemical synthesis of semi-condensed ambipolar perinone polymers with phthaloperine (p1) or phenanthroline (p2) skeleton from available and cheap perimidine precursors. Polymerization of perimidine derivatives varies in efficiency depending on the monomer, but overall is highly efficient, especially when electropolymerization is used. Electrooxidation is well controllable and provides a certain characteristic share of new bonds in the structure of perimidine polymers: semi-ladder bis-perimidine unit, ladder bis-perimidine unit, and protonated bis-perimidine unit. Polymer p2 obtained with higher efficiency was put through broader analysis (UV-Vis, IR, ESR and quantum-chemical calculations). As indicated, donor-acceptor structure and specific intermolecular interactions of p2 assure its electrical conductivity and complex redox activity. Although protonated bonds break π-conjugation in the structure of the macromolecule, there is also a diradical state that favors intermolecular interactions and intermolecular π-conjugation channels within bis-perimidine segments. It has been proven that there is a diradical state which appears as an intermediate state between the oxidized and reduced states of the protonated polymer unit. This work positions perimidine polymers as a versatile ambipolar multiredox p- and n-type conductor, indicating a potential for expanding perinone-based perylene-diperimidine polymers for innovative electronics and (bio)sensors.

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Prediction of water-conducting fractured zone (WCFZ) of mine overburden is the premise for reducing or eliminating water inrush hazards in undersea mining. To obtain a more robust and precise prediction of WCFZ in undersea mining, a WCFZ prediction dataset with 122 cases of fractured zones was constructed. Five machine learning algorithms (linear regression, XGBRegressor, RandomForestRegressor, LineareSVR, and KNeighborsRegressor) were employed to develop five corresponding predictive models, taking multiple factors into account.The optimal parameters for each model are obtained through ten-fold cross-validation (10CV). The model's predictive performance was validated and assessed using two metrics, namely the coefficient of determination (R2) and mean squared error (MSE). A comparison was made with the regression performance of commonly used empirical formulas. The results indicate that the constructed model outperforms reliance solely on theoretical criteria, showing a high R2 value of up to 0.925 and a low MSE value of 3.61. The proposed model was validated in a recently established mining area on Sanshan Island, China. It shows low absolute and relative errors of 0.71 m and 2.01%, respectively, between the predicted value from the model and observation result from the field, demonstrating a high level of consistency with on-site conditions. This paves a path to leveraging machine learning algorithms for predicting the height of WCFZ.

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gLiving materials can achieve unprecedented function by combining synthetic materials with the wide range of cellular functions. Of interest are situations where the critical properties of individual abiotic and biotic elements improve via their combination. For example, integrating electroactive bacteria into conjugated polyelectrolyte (CPE) hydrogels increases biocurrent production. One observes more efficient electrical charge transport within the CPE matrix in the presence of Shewanella oneidensis MR-1 and more current per cell is extracted, compared to traditional biofilms. Here, the origin of these synergistic effects are examined. Transcriptomics reveals that genes in S. oneidensis MR-1 related to bacteriophages and energy metabolism are upregulated in the composite material. Fluorescent staining and rheological measurements before and after enzymatic treatment identified the importance of extracellular biomaterials in increasing matrix cohesion. The synergy between CPE and S. oneidensis MR-1 thus arises from initially unanticipated changes in matrix composition and bacteria adaption within the synthetic environment.

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The low sensitivity of liquid-state nuclear magnetic resonance (NMR) can be overcome by hyperpolarizing nuclear spins by dissolution dynamic nuclear polarization (dDNP). It consists of transferring the near-unity polarization of unpaired electron spins of stable radicals to the nuclear spins of interest at liquid helium temperatures, below 2 K, before melting the sample in view of hyperpolarized liquid-state magnetic resonance experiments. Reaching such a temperature is challenging and requires complex instrumentation, which impedes the deployment of dDNP. Here, we propose organic conductive polymers such as polyaniline (PANI) as a new class of polarizing matrices and report 1H polarizations of up to 5%. We also show that 13C spins of a host solution impregnated in porous conductive polymers can be hyperpolarized by relayed DNP. Such conductive polymers can be synthesized as chiral and display current induced spin selectivity leading to electron spins hyperpolarization close to unity without the need for low temperatures nor high magnetic fields. Our results show the feasibility of solid-state DNP in conductive polymers that are known to exhibit chirality-induced spin selectivity.

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With rapid advancements in health and human-computer interaction, wearable electronic skins (e-skins) designed for application on the human body provide a platform for real-time detection of physiological signals. Wearable strain sensors, integral functional units within e-skins, can be integrated with Internet of Things (IoT) technology to broaden the applications for human body monitoring. A significant challenge lies in the reliance of most existing wearable strain sensors on rigid external power supplies, limiting their practical flexibility. In this study, we present an innovative strategy to fabricate glutaraldehyde (GA)-poly(vinyl alcohol) (PVA)/cellulose nanocrystals (CNC)/Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) conductive hydrogels through multiple hydrogen bonding systems. Combining the advantageous rheological properties of the precursor solution and the high specific surface area after freeze-thaw cycling, we have created a self-powered sensing system prepared by large-area printing using direct ink writing (DIW) printing. The resulting conductive hydrogel exhibits commendable mechanical properties (411 KPa), impressive stretchability (580 %), and robust self-healing capabilities (>98.3 %). The strain sensor, derived from the conductive hydrogel, demonstrates a gauge factor (GF) of 2.5 within a stretching range of 0-580 %. Additionally, the resultant supercapacitor displays a peak energy density of 0.131 mWh/cm3 at a power density of 3.6 mW/cm3. Benefiting from its elevated strain response and remarkable power density features, this self-powered strain sensing system enables the real-time monitoring of human joint motion. The incorporation of a 5G transmission module enhances its capabilities for remote data monitoring, thereby contributing to the progress of wireless tracking technologies for self-powered electronic skin.

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OBJECTIVE: This prospective study assessed the efficacy of the Cochlear™ Osia® 2 System compared to the previous Baha® Attract System in patients with mixed or conductive hearing loss (MHL/CHL). METHODS: In this prospective case-control study, 10 patients (2 men and 8 women) with MHL/CHL were implanted with the Osia® 2 System. Their audiological outcomes were compared with 13 patients (2 men and 11 women) who had previously been implanted with the transcutaneous Baha® Attract system. We compared the complications and compliance of the two groups. Also, in the Osia 2 System group, subjective satisfaction was assessed using the Korean version of the International Outcome Inventory for Hearing Aids (K-IOI-HA) questionnaire and the Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaire. RESULTS: Complications such as poor magnetization, pain & infection, and abnormal noise were more common in the Baha Attract group, although not statistically significant. Also, the Osia 2 group exhibited better compliance. Subjective satisfaction was assessed using the K-IOI-HA and APHAB questionnaires with the Osia 2 group, revealing significantly improved scores in ease of communication, reverberation, background noise, and higher K-IOI-HA scores post-implantation. Postoperative-aided thresholds with both systems were significantly lower than preoperative-unaided thresholds, with the Osia 2 System demonstrating notably high satisfaction levels. Although both systems showed similar preoperative and postoperative word-recognition scores, the Osia 2 System provided greater audiological gain, especially at 2 kHz and 4 kHz frequencies. Additionally, the functional gain of both systems was comparable across all frequencies. CONCLUSIONS: The Osia 2 System demonstrated high subjective satisfaction and improved audiological outcomes compared to the Baha Attract system in patients with conductive or mixed hearing loss. Its superior audiological gain, particularly at critical frequencies, along with better compliance, suggests it as a favorable option for this patient population.

Assuntos

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Background: Congenital cholesteatoma is defined as a white mass behind an intact eardrum without a history of otitis media or previous otologic procedures. Congenital cholesteatoma is a relatively rare disease that accounts for about 2% to 5% of all cholesteatomas. However, the actual incidence rate of congenital cholesteatoma may be underestimated. Conductive hearing loss is the most common presenting symptom. The current study aims to describe the clinical characteristics and management of patients with congenital cholesteatoma and promote awareness of the disease in unilateral or asymmetric conductive hearing loss patients. Methods: In this study, we report a case series of 3 patients including 1 child, 1 adolescent, and 1 young adult, managed in our department between June and August 2023, and present a summary of the literature. Results: Congenital cholesteatoma is primarily a pediatric disease, but it has also been reported in adults. Two cases presented with unilateral secretory otitis media, and 1 case presented with asymmetric unilateral conductive hearing loss. Two patients of Potsic stage III congenital middle ear cholesteatomas underwent transcanal endoscopic ear surgery, and 1 patient of Potsic stage IV underwent conventional microscopic approach canal wall-up mastoidectomy combined with endoscopy. Conclusions: In children or young adults with persistent unilateral or asymmetric conductive hearing loss, congenital middle ear cholesteatoma should be considered. Congenital cholesteatoma cannot be ruled out in children with unilateral secretory otitis media.

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Refractory diabetic wounds are a devastating and rapidly growing clinical problem, which is associated with high incidence rates, mortality, and recurrence rates. Therapeutic angiogenesis in wound tissues is essential to the healing of diabetic wounds. However, the presence of excessive oxidative stress in diabetic wounds hinders angiogenesis, and conventional anti-oxidative approaches are inefficient to compensate for the systematically impaired angiogenesis. Here, a multifunctional supramolecular hyaluronic acid hydrogel dressing for diabetic wounds is successfully designed and constructed (GHPM). The GHPM hydrogel features outstanding properties, including excellent tissue adhesion, antibacterial ability, conductivity, and antioxidant properties. Based on the dynamic crosslinking structure, the GHPM hydrogel also presents adequate injectable and self-healing capabilities, which play a vital role in covering irregular or deep wounds. Additionally, diabetic wounds treated with GHPM hydrogel showed a significant acceleration of wound closure by preventing wound infection, reducing oxidative stress, and accelerating collagen deposition. More interestingly, the combination of electrical stimulation and GHPM hydrogel can effectively promote angiogenesis and neurogenesis, further accelerating diabetic wound healing in an all-around way. This advanced collaborative strategy opens a new avenue in treating diabetic wounds.

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The increasing demand for advanced biomaterials in nerve tissue engineering presents numerous challenges due to the complexity of nerve tissues and the need for materials that can accurately replicate their intricate structure and function. In response, this study introduces a novel injectable hydrogel that is thermosensitive, self-healing, and conductive, offering promising potential for heart and nerve tissue engineering applications. The hydrogel is based on collagen and hyaluronic acid functionalized with 3-aminopropyl-triethoxysilane (APTES)-grafted oxidized bacterial cellulose and gold nanoparticles (~50 nm). Rheological analysis reveals a substantial enhancement in the elastic modulus of the collagen-hyaluronic acid matrix with the incorporation of bacterial cellulose/gold nanoparticles, improving by an order of magnitude at 1 % strain. This improvement comes with a slight decrease in gelation temperature, from 36 °C to 32 °C. Besides thermo-sensitivity, the nanocomposite hydrogel exhibits a remarkable self-sealing response (about 80 % effectiveness) due to reversible physical crosslinking. Electrical spatial resistance measurements on human embryonic stem cell-derived cardiomyocytes-loaded hydrogels yield a value of ~0.1 S/m, which is suitable for electrical stimulation. In vitro extracellular field potential measurements also affirm the hydrogel's potential as an injectable scaffold for heart tissue engineering, i.e., the electrically stimulated human stem cells exhibit 47 beats per minute with a cell discharge (depletion) of 5.47 µv. A rapid gel formation in the physiological temperature (about 2 min) and high H9C2 cytotoxicity (viability of >90 % after 72 h incubation) is attainable. The developed collagen-based nanocomposite hydrogel offers an injectable, thermosensitive, and self-healing biomaterial platform for nerve or myocardium regeneration.

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Conductive hydrogels have received much attention in the field of flexible wearable sensors due to their outstanding flexibility, conductivity, sensitivity and excellent compatibility. However, most conductive hydrogels mainly focus on strain sensors to detect human motion and lack other features such as temperature response. Herein, we prepared a strain and temperature dual responsive ionic conductive hydrogel (PPPNV) with an interpenetrating network structure by introducing a covalent crosslinked network of N-isopropylacrylamide (NIPAAm) and 1-vinyl-3-butylimidazolium bromide (VBIMBr) into the skeleton of the hydrogel composed of polyvinylalcohol (PVA) and polyvinylpyrrolidone (PVP). The PPPNV hydrogel exhibited excellent anti-freezing properties (-37.34 °C) and water retention with high stretchability (∼930 %) and excellent adhesion. As a wearable strain sensor, the PPPNV hydrogel has good responsiveness and stability to a wide range of deformations and exhibits high strain sensitivity (GF=2.6) as well as fast response time. It can detect large and subtle body movements with good signal stability. As wearable temperature sensors, PPPNV hydrogels can detect human physiological signals and respond to temperature changes, and the volumetric phase transition temperature (VPTT) can be easily controlled by adjusting the molar ratio of NIPAAm to VBIMBr. In addition, a bilayer temperature-sensitive hydrogel was prepared with the temperature responsive hydrogel by two-step synthesis, which shows great promising applications in temperature actuators.

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OBJECTIVE: A new, active transcutaneous bone conduction device (BCD) was FDA-approved in 2019 in the USA. This systematic review sought to evaluate early outcomes associated with Osia implantation. METHODS: A systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Four databases were reviewed: PubMed, Scopus, Cochrane CENTRAL, and CINAHL. Studies were included if they described audiometric, surgical characteristics/complications, or adverse events associated with the Osia BCD. Exclusion criteria: non-English language studies, animal investigations, reviews/meta-analyses, case reports, database studies. RESULTS: Eighteen studies with 336 patients were included. Mean age at implantation was 37.9 years. About 79.5% of patients had MHL/CHL and 19.5% had SSD/SHL. Mean operative time was 71.6 minutes. Mean PTA gain from unaided conditions was 35.4 dB. Mean functional gain at high frequency (6 kHz and above) from aided conditions was 16.1 dB. Mean improvement in speech recognition thresholds was 19.1 dB from unaided conditions. Adverse events (all types) were reported in 20.1% of cases. Across all studies, the postoperative infection rate was 5%. About 2% of patients reported magnet retention issues. About 1.65% of cases were complicated by hematomas. CONCLUSIONS: Under systematic literature review, the Osia BCD has been associated with low complication rates, relatively short operative times, and good audiometric and speech outcomes, notably high frequency gain >6 kHz. More advanced audiometric outcome reporting remains limited and audiometric data and patient reported outcome measures were reported heterogeneously.

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OBJECTIVE: To summarize current knowledge on the indications, surgical strategies, and auditory outcomes of revision stapes surgery (RSS) for otosclerosis. DATA SOURCES: The search was conducted in PubMed, Scopus, and Web of Science online databases, including papers published since 2000. REVIEW METHODS: The study was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. We considered original series describing RSS for otosclerosis, reporting postoperative hearing outcomes according to the American Academy of Otolaryngology-Head and Neck Surgery guidelines for conductive hearing loss (CHL) for at least 30 consecutive cases. The quality of included studies was assessed with the Joanna Briggs Institute checklist. Pooled proportion and odds ratio (OR) meta-analysis were conducted using random effect models. RESULTS: Nineteen studies were included, for a total of 2602 patients (2735 ears) and 2359 postoperative hearing results. RSS was mostly performed for recurrent CHL with air-bone gap (ABG)>20 dB. Multiple concomitant causes were often present, with prosthesis placement defect and incus necrosis as the most common causes. The pooled proportion of postoperative ABG<10 dB and ABG<20 dB was 57.2% (95% confidence interval [CI]: 52.8%-61.4%) and 79% (95% CI: 76.0%-81.8%), respectively. Dead ears were 1.2% (95% CI: 0.7%-2.1%). Compared to primary surgery, RSS had a significantly lower rate of ABG<10 dB (OR = 0.36, 95% CI: 0.24%-0.54%; P < .001). Both revision incudostapedotomy with/without incus reconstruction and malleovestibulopexy are viable options with nonsignificant differences in ABG closure rates (P = .182). CONCLUSION: RSS is challenging and requires the surgeon to carefully evaluate all potential causes of previous failure and tailor the intervention according to intraoperative findings. In most cases, ABG closure within 20 dB can be achieved with a relatively low risk of dead ears.

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Smart hydrogels have recently garnered significant attention in the fields of actuators, human-machine interaction, and soft robotics. However, when constructing large-scale actuated systems, they usually exhibit limited actuation forces (≈2 kPa) and actuation speeds. Drawing inspiration from hairspring energy conversion mechanism, an elasticity-plasticity-controllable composite hydrogel (PCTA) with robust contraction capabilities is developed. By precisely manipulating intermolecular and intramolecular hydrogen-bonding interactions, the material's elasticity and plasticity can be programmed to facilitate efficient energy storage and release. The proposed mechanism enables rapid generation of high contraction forces (900 kPa) at ultra-high working densities (0.96 MJ m-3). Molecular dynamics simulations reveal that modifications in the number and nature of hydrogen bonds lead to a distinct elastic-plastic transition in hydrogels. Furthermore, the conductive PCTA hydrogel exhibits multimodal sensing capabilities including stretchable strain sensing with a wide sensing range (1-200%), fast response time (180 ms), and excellent linearity of the output signal. Moreover, it demonstrates exceptional temperature and humidity sensing capabilities with high detection accuracy. The strong actuation power and real-time sensory feedback from the composite hydrogels are expected to inspire novel flexible driving materials and intelligent sensing systems.

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Conductive hearing loss caused by external or middle ear problems prevents the transmission of sound waves from the external auditory canal to the cochlea, and it is a common condition, especially in pediatric patients aged 1-5 years. The most common etiological factors are otitis media and cerumen during childhood. In some patients, external and middle ear functions and structures may be normal bilaterally despite the air-bone gap on the audiogram. This condition, which is often a missed diagnosis in children, is defined as a pseudo-conductive hearing loss (PCHL) caused by third window syndromes (TWSs) such as semicircular canal dehiscence, inner ear malformations with third window effect, and perilymphatic fistula. In this review of the literature, the authors emphasize the pitfalls of pediatric audio-vestibular evaluation on TWSs as well as the key aspects of this evaluation for the differential diagnosis of PCHL brought on by TWSs. This literature review will provide audiologists and otologists with early diagnostic guidance for TWSs in pediatric patients.

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The addition of iron-based conductive materials has been extensively validated as a highly effective approach to augment methane generation from anaerobic digestion (AD) process. In this work, it was additionally discovered that Fe3O4 notably suppressed the production of hazardous H2S gas during sludge AD. As the addition of Fe3O4 increased from 0 to 20 g/L, the accumulative H2S yields decreased by 89.2 % while the content of element sulfur and acid volatile sulfide (AVS) respectively increased by 55.0 % and 30.4 %. Mechanism analyses showed that the added Fe3O4 facilitated sludge conductive capacity, and boosted the efficiency of extracellular electron transfer, which accelerated the bioprocess of sulfide oxidation. Although Fe3O4 can chemically oxidize sulfide to elemental sulfur, microbial oxidation plays a major role in reducing H2S accumulation. Moreover, the released iron ions reacted with soluble sulfide, which promoted the chemical equilibrium of sulfide species from H2S to metal sulfide. Microbial analysis showed that some SRBs (i.e., Desulfomicrobium and Defluviicoccus) and SOB (i.e., Sulfuritalea) changed into keystone taxa (i.e., connectors and module hubs) in the reactor with Fe3O4 addition, showing that the functions of sulfate reduction and sulfur oxidation may play important roles in Fe3O4-present system. Fe3O4 presence also increased the content of functional genes encoding sulfide quinone reductase and flavocytochrome c sulfidedehydrogenase (e.g., Sqr and Fcc) that could oxidize sulfide to sulfur. The impact of other iron-based conductive material (i.e., zero-valent iron) was also verified, and the results showed that it could also significantly reduce H2S production. These findings provide new insights into the effect of iron-based conductive materials on anaerobic process, especially sulfur conversion.