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Abstract MnO2 nanowires coated with conjugated microporous polymers (CMP) are applied as triboelectric energy harvesting materials. The tribopositive performance of the CMP shells is enhanced with the assistance of MnO2 nanowires (MnO2 NW), likely due to cationic charge transfer from the tribopositive CMP layers to the surface Mn2+ and Mn3+ species of MnO2 NW. This is supported by model studies. The MnO2@CMP‐2 with sub‐10 nm thick CMP layers shows promising triboelectric output voltages up to 576 V and a maximum power density of 1.31 mW cm−2. Spring‐assisted triboelectric nanogenerators fabricated with MnO2@CMP‐2/PVP‐3 films are used as power supplies to operate electronic devices.

Abstract Background For the surgical treatment of oral cancer, it is sometimes necessary to expand intraoral access within the oral cavity. The “swing approach” that involves lip splitting of the mandible and temporary mandibular osteotomy and the “visor approach” that does not split the lower lip and mandible are mainly used. This study analyzed postoperative outcomes such as complications, recurrence rate, and survival rate by these two approaches. The goal of this study is to evaluate the surgical outcomes of patients using these two approaches, to propose effective perioperative management for oral cancer surgery, and to compare the prognosis of oral cancer patients. Materials and methods From 2005 to 2020, 29 patients who underwent surgery at the Department of Oral and Maxillofacial Surgery of Pusan National University Dental Hospital for oral cancer lesions occurred in the mandible, floor of mouth, and tongue were selected for the study. Based on the surgical approach used, a chart review was conducted on various prognostic clinical factors such as the patients’ sex and age, primary site, TNM stage, histopathologic grade, recurrence and metastasis, postoperative survival rate, adjuvant chemo-radiation therapy, satisfaction with aesthetics/function/swallowing, length of hospital stay, tracheostomy and its duration, and neck dissection and its type. Statistical analysis was conducted using SPSS 25.0 (SPSS Inc., Chicago, IL) through Fisher’s exact t-test. Result There was no statistically significant difference between two groups in terms of clinical and pathological findings, such as survival rate, the need for adjuvant therapies, and the local recurrence rate. Although better outcomes were observed in terms of function, aesthetics, and postoperative complications in the group with visor approach, there was still no statistically significant difference between two groups. However, the duration of hospital stay was shorter in the visor approach group. Conclusion There was no statistically significant difference in clinical prognostic factors between the swing approach and the visor approach. Therefore, when choosing between the two approaches for the ablation of oral cancer, it is considered to select the surgical priority approach that can be easy access based on the size and location of the lesion. The visor approach had advantages of aesthetics and healing period.

Low-light images often lack visibility and information, and traditional methods of adjusting camera sensitivity and exposure time can result in visual quality degradation. In this paper, we propose a low-light enhancement method that utilizes two novel approaches to address these issues. The first approach involves using multi-band NIR (Near Infra-red) to preserve structural components, while a transformer-based cross-attention module efficiently calculates the correlation between NIR and RGB for effective fusion. The second approach involves implementing dual-teacher knowledge distillation, where normal- and mid-light teacher networks transfer low-light enhancement knowledge to the student. Our proposed method produces better color and detail restoration results than existing methods, particularly in ultra low-light environments. We also provide our own datasets for two different low-light conditions, enabling wide evaluations and ablation studies.

Abstract Bioresorbable bioelectronics, with their natural degradation properties, hold significant potential to eliminate the need for surgical removal. Despite notable achievements, two major challenges hinder their practical application in medical settings. First, they necessitate sustainable energy solutions with biodegradable components via biosafe powering mechanisms. More importantly, reliability in their function is undermined by unpredictable device lifetimes due to the complex polymer degradation kinetics. Here, we propose an on-demand bioresorbable neurostimulator to address these issues, thus allowing for clinical operations to be manipulated using biosafe ultrasound sources. Our ultrasound-mediated transient mechanism enables (1) electrical stimulation through transcutaneous ultrasound-driven triboelectricity and (2) rapid device elimination using high-intensity ultrasound without adverse health effects. Furthermore, we perform neurophysiological analyses to show that our neurostimulator provides therapeutic benefits for both compression peripheral nerve injury and hereditary peripheral neuropathy. We anticipate that the on-demand bioresorbable neurostimulator will prove useful in the development of medical implants to treat peripheral neuropathy.

In this study, a dual-band low-noise amplifier (LNA) was implemented by applying a transformer-based neutralization technology to the W-band. Incorporating the neutralization technique was difficult owing to performance degradation in the W-band. However, circuit performance was enhanced thanks to the layout optimization of transformer-based neutralization networks, and the improved operation was confirmed in the W-band. The neutralization technique was implemented in four stages with a 0.1-μm gallium arsenide (GaAs) pseudomorphic high-electron-mobility-transistor monolithic microwave integrated circuit LNA. The LNA showed small signal gains of 20.3 dB and 21.7 dB and noise figures of 5.0 dB and 6.4 dB (at 84 GHz and 96 GHz, respectively) while consuming 46 mW from a 1-V supply.

Radio frequency (RF) hyperthermia focuses on raising the target area temperature to a value exceeding 45°C. Collagen is stimulated when the temperature rises to 45°C at the dermal layer, resulting in skin tightening. However, most studies on RF hyperthermia have focused on tumor ablation or using electrodes to radiate an electromagnetic field, which is highly inefficient. This study proposed a non-invasive RF hyperthermia skin-tightening system with a compact metamaterial-filled waveguide aperture antenna. The proposed RF system increased the temperature by 11.6°C and 35.3°C with 20 and 80 W of 2.45 GHz RF power, respectively, within 60 s and exhibited a very focused effective area. Furthermore, a metamaterial was proposed to reduce the size of the waveguide aperture antenna and focus the electromagnetic field in the near-field region. The proposed metamaterial-filled waveguide aperture antenna was compact, measuring 10 mm × 17.4 mm, with a peak gain of 2.2 dB at 2.45 GHz. The measured hyperthermia performance indicated that the proposed RF system exhibited better power- and time-efficient hyperthermia performance than other RF hyperthermia systems in the cosmetic skin lifting commercial market. The proposed RF hyperthermia systems will be applied into a new generation of beauty cosmetic devices.

Human deep core temperature is a vital health condition parameter. Human body temperature change begins from the deep core followed by change in skin temperature. Measuring deep core temperature is the first action for rapid detection of health condition. Infrared thermometer can measure temperature; however, the only measures the skin temperature. The use of microwave radiometer for measuring deep core temperature has garnered attention. The antenna, an important component of the microwave radiometer, has rarely been focused upon in studies on measurement of deep core temperature. This study proposed compact dual-band on-body near field antenna with a reflector for measuring deep core temperature using a microwave radiometer. The proposed antenna size is 13 mm $\boldsymbol {\times }\,\,13$ mm with a 20 mm $\boldsymbol {\times }\,\,20$ mm reflector 3 mm above the radiator. The proposed antenna was simulated and designed on a full 3D body model and simplified flat phantom and measured on real human wrist. It achieved sufficient bandwidth and volume loss density can be used in microwave radiometers for measuring deep core temperature.

This paper presents a highly integrated radio frequency (RF) CMOS receiver module for monitoring the core body temperature thermometer, which operates in the dual band 1.35 and 2.75 GHz ranges. The RF receiver IC, such as a Dicke radiometer, includes the full receiver circuits, RF switch and modulator, and duty calibrating circuit using a 65 nm CMOS process. With the proposed duty cycle modulation, accurate temperature sensing is achievable even with a receiver gain mismatch and fluctuation. The measured temperature ranges from 22 to 47.3°C, and the measured voltage slope is 2.97 mV/ms • °C, and the temperature error is less than 0.9°C in 1.35 GHz band. The radiometric RF CMOS IC has a size of $1.6\times2.3$ mm2 and the current consumption of 52 mW. Unlike the general skin temperature measurement of existing infrared (IR) sensors, the RF microwave core body thermometer equipped with an RF receiver IC that measures core body temperature inside a human body will be used in various fields as a digital healthcare and medical device.

The LPS-induced inflammation model is widely used for studying inflammatory processes due to its cost-effectiveness, reproducibility, and faithful representation of key hallmarks. While researchers often validate this model using clinical cytokine markers, a comprehensive understanding of gene regulatory mechanisms requires extending investigation beyond these hallmarks. Our study leveraged multiple whole-blood bulk RNA-seq datasets to rigorously compare the transcriptional profiles of the well-established LPS-induced inflammation model with those of several human diseases characterized by systemic inflammation. Beyond conventional inflammation-associated systems, we explored additional systems indirectly associated with inflammatory responses (i.e., ISR, RAAS, and UPR) using a customized core inflammatory gene list. Our cross-condition-validation approach spanned four distinct conditions: systemic lupus erythematosus (SLE) patients, dengue infection, candidemia infection, and staphylococcus aureus exposure. This analysis approach, utilizing the core gene list aimed to assess the model’s suitability for understanding the gene regulatory mechanisms underlying inflammatory processes triggered by diverse factors. Our analysis resulted in elevated expressions of innate immune-associated genes, coinciding with suppressed expressions of adaptive immune-associated genes. Also, upregulation of genes associated with cellular stresses and mitochondrial innate immune responses underscored oxidative stress as a central driver of the corresponding inflammatory processes in both the LPS-induced and other inflammatory contexts.

Triboelectric nanogenerators (TENGs) have been widely investigated to harness mechanical energy that is driven by repetitive human motion. Conventional human motion-driven TENGs are mostly based on contact–separation (CS) mode, but their energy harvesting performance is limited due to the high crest factor (the ratio of the peak to the RMS value of output voltage). Here, we demonstrate a new rolling type triboelectric nanogenerator (RL-TENG), exhibiting the lower crest factor than CS mode TENGs, using a metal layer and graphene nanoplatelets-doped PDMS. These additions helped improve the dielectric constant and the charge storage capacity of the TENG, which led to a high electrical output while minimizing surface damage. As compared to a pristine TENG, our device, a RL-TENG, generated an open-circuit peak voltage of 75.2 V, which was almost 15 times higher than that of the pristine device, and a short-circuit peak current of 7.36μA, which was 12 times higher. With a dual-side double-belt TENG (DB-TENG), these values were improved to 164 V and 10μA. Lastly, our device was used in a real-life application, to harvest mechanical energy from the movement of the human elbow while walking, and was able to produce a high voltage output of up to 821 V. These results show that the DB-TENG can be used for high-efficiency harvesting of energy from human motion.

Deep core temperature is the most basic and important information about health conditions. Non-contact infrared thermometers are widely used for human body temperature measurement. However, infrared thermometers are not suitable for deep core temperature measurement. To overcome this limitation, measuring deep core temperature with a microwave radiometer is gaining attention. In this study, we propose a dual-band on-body near-field antenna for measuring deep core temperature with a microwave radiometer application. The proposed antenna has a compact size of 20 mm $\times30$ mm $\times1.52$ mm. The negative (−) radiator is located at the top of the substrate and the positive (+) radiator is located at the bottom of the substrate. The dual-band is proposed for high temperature resolution and is achieved by a meander slot on the radiator. The antenna is fabricated on a high dielectric substrate and the stubs are proposed to reduce the size of the proposed antenna so that it can be used on various human body parts.

This paper presents experimental and numerical analysis results regarding the effects of an incomplete penetration defect on the fatigue lives of socket welded pipes. For the experiment, four-point bending fatigue tests with various defect geometries (defect depth and circumferential length) were performed, and test results are presented in terms of stress-life data. The results showed that for circumferentially short defects, the fatigue life tends to increase with increasing crack depth, but for longer defects, the trend becomes the opposite. Finite element analysis showed that for short defects, the maximum principal stress decreases with increases in crack depth. For a longer defect, the opposite trend was found. Furthermore, the maximum principal stress tends to increase with an increase in defect length regardless of the defect depth.

Air-transmitted pathogens are a recognized threat to public health. Here, the authors develop a self-powered, rapid disinfection method toward air-transmitted microbes using the localized electric field to damage the outer structures of microbes driven by a triboelectric nanogenerator.

(1) Background: The accurate diagnosis of periodontal disease typically involves complex clinical and radiologic examination. However, recent studies have demonstrated the potential of deep learning in improving diagnostic accuracy and reliability through the development of computer-aided detection and diagnosis algorithms for dental problems using various radiographic sources. This study focuses on the use of panoramic radiographs, which are preferred due to their ability to assess the entire dentition with a single radiation dose. The objective is to evaluate whether panoramic radiographs are a reliable source for the detection of periodontal bone loss using deep learning, and to assess its potential for practical use on a large dataset. (2) Methods: A total of 4083 anonymized digital panoramic radiographs were collected using a Proline XC machine (Planmeca Co., Helsinki, Finland) in accordance with the research ethics protocol. These images were used to train the Faster R-CNN object detection method for detecting periodontally compromised teeth on panoramic radiographs. (3) Results: This study demonstrated a high level of consistency and reproducibility among examiners, with overall inter- and intra-examiner correlation coefficient (ICC) values of 0.94. The Area Under the Curve (AUC) for detecting periodontally compromised and healthy teeth was 0.88 each, and the overall AUC for the entire jaw, including edentulous regions, was 0.91. (4) Conclusions: The regional grouping of teeth exhibited reliable detection performance for periodontal bone loss using a large dataset, indicating the possibility of automating the diagnosis of periodontitis using panoramic radiographs.

The purpose of this study is to analyze the potential and merits of narrative-based virtual fieldwork in preservice geography teacher education. Virtual fieldwork can effectively complement, implement, and foster fieldwork. In addition, narrative is closely related to fieldwork. To proceed with the research, this study developed a travel geography class for PGTs (primary geography teachers) that included narrative-based fieldwork assignments. This study deduced four themes to illuminate the potential of narrative-based virtual fieldwork (NVF) by using a phenomenographic analysis of the reflective journals written by the participating preservice geography teachers who completed their NVF assignments. The results of this study suggested that the NVF possibly involves the PGTs’ engagement in, procedural and contextual understanding of, and teaching knowledge of virtual fieldwork thanks to its specific characteristic of integrating narrative and virtual fieldwork. The results of this study provide concrete discussions on the potential and merits of NVF in PGTE.

Abstract The triboelectric effect is a ubiquitous phenomenon in which the surfaces of two materials are easily charged during the contact‐separation process. Despite the widespread consequences and applications, the charging mechanisms are not sufficiently understood. Here, the authors report that, in the presence of a strain gradient, the charge transfer is a result of competition between flexoelectricity and triboelectricity, which could enhance charge transfer during triboelectric measurements when the charge transfers of both effects are in the same direction. When they are in the opposite directions, the direction and amount of charge transfer could be modulated by the competition between flexoelectric and triboelectric effects, which leads to a distinctive phenomenon, that is, the charge transfer is reversed with varying forces. The subsequent results on the electrical power output signals from the triboelectrification support the proposed mechanism. Therefore, the present study emphasizes the key role of the flexoelectric effect through experimental approaches, and suggests that both the amount and direction of charge transfer can be modulated by manipulating the mixed triboelectric and flexoelectric effects. This finding may provide important information on the triboelectric effect and can be further extended to serve as a guideline for material selection during a nanopatterned device design.

Purpose The standard method used to diagnose central precocious puberty (CPP) is the gonadotropin releasing hormone stimulation test (GnRHST). However, this test is inconvenient for children because it is time-consuming and requires multiple samples. This study aimed to determine the reliability of morning unstimulated luteinizing hormone (mLH) level when screening for CPP, with an emphasis on the influence of diurnal variation. Methods This study included 160 girls with signs of early puberty (SMR 2) under 8 years of age. They were classified as CPP or non-CPP based on their standard GnRHST. The auxological, biochemical, and hormonal characteristics of subjects were retrospectively evaluated. The prognostic value of single morning unstimulated gonadotropin level was examined for use in CPP screening. Results Of 160 patients, 121 (75.6%) presented with CPP, and 39 (24.4%) were determined to be prepubertal. The mLH/mFSH (morning unstimulated follicular stimulating hormone) ratio showed significant differences between the 2 groups (P

Summary: Water treatment based on advanced oxidation processes (AOPs) supplies clean water to rural areas lacking electric power supply and/or during natural disasters and pandemics. Considering the abundance of solar energy in the ambient environment, the solar-driven AOPs show an interesting potential to driving the water purification process. Involving the energy harvester (EH) that harvests mechanical or thermal energy into electricity to the solar-driven AOPs can achieve sustainable and self-powered water purification. Herein, we summarize the recent progress in the application of solar-induced hybrid EHs that harvest solar and mechanical/thermal energy simultaneously to drive AOP water treatment. A detailed discussion of the solar-induced hybrid EHs enabling AOP water treatment based on the mechanisms of piezo-, tribo-, pyro-, and thermo-assisted photocatalysis is provided. In addition, this paper explores future opportunities and strategies of the solar-induced hybrid EHs to drive the AOP water treatment in actual situations with unstable and fluctuating environmental conditions.

In this study, we propose a miniaturized bandpass filter (BPF) developed by combining an approximate circular (36-gon) winding inductor, a circinate capacitor, and five air-bridge structures fabricated on a gallium arsenide (GaAs) substrate using an integrated passive device (IPD) technology. We introduced air-bridge structures into the outer metal wire to improve the capacitance per unit volume while utilizing a miniaturized chip with dimensions 1538 μm × 800 μm (0.029 λ0 × 0.015 λ0) for the BPF. The pattern was designed and optimized by simulating different dimensional parameters, and the group delay and current density are presented. The equivalent circuit was modeled to analysis various parasitic effect. Additionally, we described the GaAs-based micro-nano scale fabrication process to elucidate the proposed IPD technology and the physical structure of the BPF. Measurements were conducted with a center frequency of 1.53 GHz (insertion loss of 0.53 dB) and a 3-dB fractional bandwidth (FBW) of 70.59%. The transmission zero was located at 4.16 GHz with restraint of 35.86 dB. Owing to the benefits from its miniaturized chip size and high performance, the proposed GaAs-based IPD BPF was verified as an excellent device for various S-band applications, such as satellite communication, keyless vehicle locks, wireless headphones, and radar.

Hexagonal Co(OH)2 nanoplates with a diameter of 1.28 ± 0.08 mm and a thickness of 52 ± 14 nm were prepared, showing facile generation of static electricity in a plastic container. Based on this observation, Co(OH)2 nanoplates were incorporated into polymer matrixes such as polyvinylpyrrolidone (PVP) and polyurethane (PU). The resultant PVP– Co(OH)2 (PVP–Co) and PU–Co(OH)2 (PU–Co) films bearing an optimal amount (0.1 wt%) of Co(OH)2 nanoplates showed dramatically-enhanced triboelectric performance, compared with pristine polymer films. While PVP and PU films exhibited output peak-to-peak voltages (Vp–p) of 249 and 423 V and output peak-to-peak currents (Ip–p) of 23 and 60 mA, respectively, with a pushing force of 2 kg f, the PVP–Co0.1 and PU–Co0.1 films showed Vp–p of 407 and 612 V with Ip–p of 41 and 85 mA, respectively. Triboelectric devices fabricated with PVP–Co0.1 and PU–Co0.1 films showed the maximum power densities of 0.38 and 1.22 mW cm−2, respectively, and worked as power sources to charge a capacitor and to operate LEDs and a calculator. We suggest that the enhanced triboelectric performance of PVP– Co0.1 and PU–Co0.1 is attributable to the facile oxidation of Co2+ to Co3+ in Co(OH)2 nanoplates. [ABSTRACT FROM AUTHOR]

An intraosseous hemangioma of the frontal bone is typically removed via a coronal incision. This procedure, while effective, can be lengthy and may result in complications such as a prominent scar and hair loss. An alternative approach involves a direct incision in the forehead, which leaves a less noticeable scar and allows a quicker recovery. However, in this specific case, the patient declined both coronal surgery and surgery through a direct forehead incision due to cosmetic concerns. Therefore, we proposed an anterior hairline incision. A 35-year-old woman presented with a firm, non-mobile, palpable mass on her right forehead. Preoperative non-contrast computed tomography revealed a heterogeneous osteolytic lesion. We performed an excisional biopsy through the anterior hairline. Postoperative non-contrast computed tomography was conducted 2 and 6 months after surgery. The wound was clean and free of complications, and there was no local recurrence. Partial resection can reduce scarring for patients who are concerned about cosmetic outcomes. However, the potential for recurrence remains a significant concern. We present this case of an anterior hairline incision for a hemangioma located in the forehead, evaluated using serial computed tomography for both preoperative and postoperative imaging. Abbreviation: CT, computed tomography. [ABSTRACT FROM AUTHOR]

Purpose: No consensus exits regarding preoperative skin antisepsis for upper extremity surgery. We aimed to determine whether the use of povidone-iodine only (single regimen) instead of povidone-iodine and alcohol-chlorhexidine (triple regimen) resulted in an increased rate of surgical site infection (SSI), and to detect any associated factors that increased the infection risk. Methods: A cross-sectional, retrospective review of medical records was conducted for patients who underwent upper extremity surgery from March 2020 to February 2021. Either the single or triple regimen was used for preoperative skin antisepsis. The rate of SSI was compared based on a marked elevation of C-reactive protein (CRP) at 2 weeks after surgery, superficial SSI, and deep SSI. Logistic regression analysis was performed to identify factors associated with SSI among the evaluated parameters. Results: Among 175 patients (male, 81 and female, 94), the single regimen was used in 78 patients (44.6%) and the triple regimen in 97 patients (55.4%). The single regimen (odds ratio [OR], 2.425; 95% confidence interval [CI], 1.040--5.655) and a surgical procedure using a metal implant (OR, 3.602; 95% CI, 1.184--10.953) were significantly associated with a marked CRP elevation at 2 weeks. However, there was no difference in SSI rates between the single and triple regimens. Diabetes mellitus (OR, 6.636; 95% CI, 1.259-34.969) was the only factor significantly associated with superficial SSI through logistic regression analysis. Conclusion: Our study suggests that the single regimen resulted in a longer CRP elevation than the triple regimen, but was similarly effective in preventing SSI for upper extremity surgery. [ABSTRACT FROM AUTHOR]