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Self-powered implantable devices have the potential to extend device operation time inside the body and reduce the necessity for high-risk repeated surgery. Without the technological innovation of in vivo energy harvesters driven by biomechanical energy, energy harvesters are insufficient and inconvenient to power titanium-packaged implantable medical devices. Here, we report on a commercial coin battery-sized high-performance inertia-driven triboelectric nanogenerator (I-TENG) based on body motion and gravity. We demonstrate that the enclosed five-stacked I-TENG converts mechanical energy into electricity at 4.9 μW/cm3 (root-mean-square output). In a preclinical test, we show that the device successfully harvests energy using real-time output voltage data monitored via Bluetooth and demonstrate the ability to charge a lithium-ion battery. Furthermore, we successfully integrate a cardiac pacemaker with the I-TENG, and confirm the ventricle pacing and sensing operation mode of the self-rechargeable cardiac pacemaker system. This proof-of-concept device may lead to the development of new self-rechargeable implantable medical devices., Self-powered implantable devices have the potential to extend device operation, though current energy harvesters are both insufficient and inconvenient. Here the authors report on a commercial coin battery-sized high-performance inertia-driven triboelectric nanogenerator based on body motion and gravity that can be used to charge a lithium-ion battery and integrated into a cardiac pacemaker.

Monolithic 3-dimensional integration (M3D) requires heat treatment techniques that should not degrade the device performance of the lower layers when applied to device fabrication in the upper layers. Deep ultraviolet (DUV) laser annealing was implemented in the crystallization of amorphous silicon and source/drain junction activation to fabricate polycrystalline silicon (poly-Si) metal-oxide-semiconductor field-effect-transistors (MOSFETs) for upper-layer devices. The poly-Si MOSFET devices were fabricated successfully on top of the bottom electronic circuit layer (isolated by a thick silicon dioxide layer). Devices on the upper and lower layers were connected through interlayer vias to form a current-starved ring oscillator. The current-to-frequency converter on the bottom layer showed a reasonable increase in frequency as the current of the poly-Si MOSFET on the upper layer increased with increasing silicon grain size, confirming that DUV laser annealing did not degrade the performance of the bottom layer devices. This opens more opportunities for using DUV laser annealing in the M3D integration.

Textile triboelectric nanogenerator (TENG) is a kind of smart textile technology that integrates traditional flexible and wearable textile materials with emerging and advanced TENG science, which not only embraces the capabilities of autonomous energy harvesting and active self-powered sensing, but also maintains original wearability and desired comfortability. With the help of the burden-free and self-sufficient wearable intelligent system, individuals can achieve convenient acquisition and efficient utilization of electric energy, which will help to promote the future development of human-oriented on-body electronics and artificial intelligence. Here, some fundamental knowledge and core elements, including the operational modes and corresponding service occasions, charge generation and transfer mechanisms, remaining challenges and potential solutions are comprehensively summarized and systematically discussed. Based on these analyses, a roadmap toward the scientific research and large-scale commercial application of textile TENGs in the next decade is highlighted at the end of the article. We believe that textile TENGs will become an indispensable part of daily clothing in the future, thus benefiting all humankind and human civilization.

This study has found that the wintertime (November–March) air quality in Seoul, Korea had been deteriorated in weekends during the period of 2016–2019. Specifically, the concentration of particulate matters (PMs) of aerodynamic diameter less than 2.5 μm (PM2.5) in weekends (Saturday–Sunday) was up to 30% higher than that in the mid-week (Wednesday–Thursday) days (probability value 2.5 on weekend could be partially explained by the differences in the concentrations of inorganic PM components including nitrate, ammonium, and sulfate between weekends and mid-week days. About 40% of the differences are attributed to the domestic sources located in the southern region to Seoul. However, domestic emission from power generations and industry sector in southern source region on weekends does not well explain the variations of the PM precursors in weekends. Therefore, a clear strategy for improving air quality on the weekend in Seoul requires steady efforts to accurately calculate regional emissions and to reveal missing emissions sources.

To investigate the efficacy of autologous serum gel in patients with lagophthalmos combined with neurotrophic persistent corneal epithelial defects (PEDs).This is retrospective, case-series study enrolled 15 patients with lagophthalmos complicated by neurotrophic PEDs refractory to medical treatment including autologous serum eye drops. They were treated with autologous serum gel in conjunction with conservative treatment. The following information was collected from medical records: demographics, underlying diseases, and past ocular history. PEDs healing time was evaluated with visual acuity, visual analog scale (VAS) scores, esthesiometer scores, and the areas of the epithelial defects.Six men and nine women with a mean age of 63.3 ± 9.9 years were included. The most common cause of the neurotrophic PEDs and lagophthalmos in this group was postherpetic infection (46.7%) and cerebral hemorrhage (26.7%) each. Two months following treatment with autologous serum gel, there was a reduction in the area of the epithelial defects (from 19.2 ± 9.9 to 0.6 ± 1.5 mmAutologous serum gel reduces symptoms and promotes corneal epithelialization of refractory neurotrophic PEDs in patients with lagophthalmos. Therefore, it may be well tolerated and a beneficial addition in the management of neurotrophic PEDs in patients with lagophthalmos.

The conversion of ecofriendly waste energy into useable electrical energy is of significant interest for energy harvesting technologies. Piezoelectric nanogenerators based on organic/inorganic hybrid materials are a key promising technology for harvesting mechanical energy due to their high piezoelectric coefficient and good mechanical flexibility. However, the negative piezoelectric effect of the polymer component in composite devices severely undermines its overall piezoelectricity, compromising the output performance of PVDF-based piezoelectric hybrid nanogenerators. Here, to conquer this, we report a two-step poling schedule to orient the dipoles of organic and inorganic components in the same direction. The optimized nanogenerator delivers a combination of high piezoelectric coefficient, great output performance, and remarkable stability. The isotropic piezoelectricity in the composite device collaborates to output a maximum voltage of 110 V and a power density of 7.8 μW cm

This study aims to answer the following research question: Is there any difference in the effects of collective intelligence on the open innovation between before (2001–2005) and after (2011–2015) of the introduction of smartphones and crowd web services regarding electronics and mathematics? The research method of this study includes multiple regression analysis, including (1) the effect of collective intelligence on open innovation (i.e., the number of citations), (2) the effect of the amount of knowledge (i.e., the number of references) on open innovation and (3) the moderating effect of the amount of knowledge (i.e., the number of references) between collective intelligence and open innovation. The research scope of this study is Scopus published papers from two periods, namely, 2001–2005 and 2011–2015. The scope here is limited to mathematics and electronics. According to the research conducted here, if the amount of knowledge increases in an economic system, collective intelligence will increasingly motivate open innovation. The implication of this study is that there are diverse methods for collective intelligence to impact open innovation and the consequent results.

Purpose To compare quantitative visual tests, such as visual acuity, contrast sensitivity, and color vision tests in patients with primary open-angle glaucoma (POAG) patients according to three different light systems with different color-rendering index (CRI). Methods This was a cross-sectional study of 36 eyes in 36 patients with POAG. Three different light systems consisting of a 3-band fluorescent lamp (CRI 80), a white LED (CRI 75), and a quantum dot LED (CRI > 95) were used. All lights had the same illuminance of 230 lx to exclude illuminance effects. The visual testing included best-corrected visual acuity (BCVA) using an ETDRS chart, a CSV-1000E contrast test, and a color test performed by the Farnsworth Munsell 100-hue test. Results There was no significant difference in BCVA (p = 0.86). There were no significant differences in the detail contrast tests according to the three light systems (p = 0.95, p = 0.94, p = 0.94, respectively, p = 0.64). There was significant difference between the three light systems in color test (p = 0.042). The color test scores with a quantum dot LED were significantly lower than those of the white LED and 3-band fluorescent lamp (p = 0.03 and 0.047, respectively). Conclusions POAG patients did not show significant differences in visual acuity scores and contrast test scores, expressed as black and white symbols, according to the different light systems. However, POAG patients tested under a quantum dot LED (CRI > 95) could distinguish color differences better than in the other light systems.

The aim of this study was to compare the antioxidant activity, chemical composition, flavor and bioactive compounds between Korean and imported velvet antlers (VAs)-derived extracts. The Korean (KVA), Russian (RVA) and New Zealand (NZVA) VAs (n=24 each, dry form) purchased from a local supplier were used in the investigation. After extracting with water (750 g VA with 6,000 mL water) for 20 h at 95°C, the VA extracts (VAE) were then used for analysis of antioxidant activity, amino acids (AAs), flavor and bioactive compounds. Compared to the RVA and NZVA, the KVA extract showed significantly higher 2,2-diphenyl 1 picrylhydrazyl (DPPH) and 2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radicals scavenging activities (p

Purpose There are unmet needs associated with the current treatment strategies for relapsed/refractory diffuse large B-cell lymphoma (DLBCL) due to the poor treatment outcomes of these strategies. Roflumilast, a selective phosphodiesterase-4 inhibitor used for treating chronic obstructive pulmonary disease, is effective against B-cell malignancy via phosphoinositide 3-kinase (PI3K)–activity suppression. We analyzed the effects of roflumilast combined with ESHAP (etoposide, cisplatin, methylprednisolone, and cytarabine) chemotherapy in experimental and clinical settings.Materials and Methods An in vitro study using lymphoma cell lines and a pilot study on relapsed/refractory DLBCL patients were conducted to investigate the effects and mechanism of the combination of roflumilast and chemotherapy. The complete response (CR), overall response rate (ORR), and 1-year progression-free survival (PFS) were analyzed.Results We found that roflumilast is efficient when combined with other chemotherapy drugs, especially cytarabine. Synergistic effects between these two drugs influence the translation of mammalian target of rapamycin and myeloid cell leukemia 1, resulting in apoptosis and inhibition of B-cell lymphoma proliferation. In clinical setting, the roflumilast group showed better rates of CR (46.2% vs. 34.6%), ORR (76.9% vs. 53.8%), and 1-year PFS (50.0% vs. 25.9%) compared with the control group, though not statistically significant. The roflumilast group showed a higher incidence of asthenia and gastrointestinal adverse events. However, grade 3 or 4 adverse events were similar in both groups.Conclusion We found that roflumilast, when combined with ESHAP chemotherapy, for relapsed/refractory DLBCL was clinically active and well tolerated. This combined treatment was able to suppress PI3K activity, which is correlated with the degree of clinical response.

With the development of smart factories, deep learning, which automatically extracts features and diagnoses faults, has become an important approach for fault diagnosis. In this article, a novel interturn short-circuit fault (ISCF) diagnosis approach using an attention-based recurrent neural network is proposed. An encoder–decoder architecture using an attention mechanism diagnoses the ISCF by estimating a fault indicator that directly reflects the severity of the fault, using currents and rotational speed signals as inputs. The attention mechanism helps the decoding process in accurate diagnosis and solves the long-term dependence problem of the encoder–decoder structure. The proposed algorithm uses only three-phase current and rotational speed as the inputs to evaluate the severity of the ISCF and enable early stage diagnosis of ISCF. The diagnosis of ISCF is achieved in various operating points and fault conditions, and no additional sensors, such as voltage and vibration sensors, are required. Experimental results for various operating and fault conditions demonstrate that the proposed method effectively diagnoses ISCFs.

This study was conducted to check the sterilization efficacy of microwave plasma (MWP) against the watermelon seeds infected with Acidovorax citrulli 11-251. Watermelon seeds were artificially vacuum inoculated to produce A. citrulli 11-251 infected seeds. Aac ImmunoStrip and scanning electron microscope (SEM) results suggests that, seeds (coat and endosperm) were infected under the concentration of 1×107/30 min. MWP sterlization process was carried out at 50 W (3 min, 5 min, and 10 min), 80 W (3 min, 5 min, and 10 min), and 100 W (3 min, 5 min, and 10 min). According to the results, MWP sterilized the artificially inoculated seed coats by 95.96% at 80 W/10 min and seed endosperms by 100% at 100 W/10 min respectively. Although, seeds were sterlized by MWP, germination rate of seeds were low as compared to non treated (negative control) seeds. Moreover, cell membrane of A. citrulli 11-251 was damaged while observed in SEM after sterilized with MWP. Further studies regarding the appropriate sterilization condition by MWP against A. citrulli infected seeds for germination will be conducted in our next study.

Acute laryngitis and acute inflammatory diseases of either infectious or non-infectious causes have similarities with herpes zoster of the vagus nerve (VHZ). We present a case which was initially diagnosis wtih acute laryngitis but finally diagnosed as VHZ. A 41-year-old male presented with an ongoing fever, throat pain and right otalgia lasting for two days with worsening symptoms despite nonsteroidal anti-inflammatory drug medication. Initially, he was treated conservatively as acute laryngitis was suspected. However, VHZ was subsequently diagnosed in this patient after considering unilateral auricular and laryngeal vesicles which were followed by ipsilateral vocal fold paresis. An antiherpetic agent and prednisolone were administered upon the presentation of vocal fold paresis. Axonotmesis was discovered by laryngeal electromyography one week after the appearance of vocal fold paresis. All symptoms subsided after one month. These results highlight the importance of understanding vagus nerve function in developing a differential diagnosis for laryngitis and VHZ.

Noncontact-mode-operating triboelectric nanogenerators (TENGs), which directly avoid physical contact, are fascinating self-powered systems aimed at long-life operation and minimizing rubbing frict...

In 2017, Talaromyces variabilis was isolated during a survey of fungal diversity in field soils in Korea. This isolate was described based on its morphological and molecular characteristics and it was identified molecularly using the partial 18S-ITS1-5.8S-ITS2-28S rDNA region and calmodulin (CaM)-encoding gene sequence data. Thus, this study reported morphological and multigene sequence characterization of T. variabilis.

Background and purpose: Pyogenic spinal infection (PSI) has recently been on the rise due to aging and increasing degenerative spinal disease related procedures. PSI requires long-term antibiotic treatment and is followed by sustained functional disability even after successful treatment. This study aimed to analyze the clinical factors associated with medical burden and functional status of PSI. Methods: This retrospective study involved patients with non-postoperative PSI of thoraco-lumbo-sacral area in a single tertiary hospital. The length/cost of hospitalization with an antibiotic therapy and severity of back pain using the short form 36 (SF-36) were defined as the medical burden and functional status, respectively. We analyzed the clinical factors associated with medical burden and functional status. Results: We enrolled 142 patients (91 males and 51 females). The length and cost of hospitalization were 55.56 ± 27.09 (7–172) days and $14,070.17 ± 9289.39 (1611.87–48,722.35), respectively. A recurrence rate of 7.7% (11/142) and significant improvement of SF-36 at six months after completion of antibiotic treatment were noted (p < 0.05). Procedure-related (OR 2.702), C-reactive protein (CRP; OR 1.062), bacteremia (OR 4.966), additional surgical treatment (OR 6.524), recurrence (OR 12.453), and paraspinal abscess (OR 5.965) for above-average length of hospitalization were observed; female (OR 4.438), CRP (OR 1.071), bacteremia (OR 4.647), additional surgical treatment (OR 6.737), recurrence (OR 22.543), and extent of lesion (OR 1.431) for above-average cost of hospitalization; leg weakness (OR 15.966), white blood cell (WBC; OR 1.116), Charlson’s comorbidity index (CCI, OR 1.485), and identification of causative bacteria (OR 2.913) for below-average initial SF-36 were observed; leg weakness (OR 7.975) and WBC (OR 1.094) for below-average 6-month SF-36 were the statistically significant clinical factors in the multivariable logistic regression analysis (p < 0.05). Conclusion: Recurrence and leg weakness were identified as the most important clinical factors for medical burden and functional status in PSI, respectively. We think that it is necessary to actively suppress recurrence and manage neurological deficits for decreasing medical burden and achieving favorable functional outcome in the treatment of PSI.

Increased concentration of airborne particulate matter (PM) in the atmosphere alters the degree of polarization of skylight which is used by honeybees for navigation during their foraging trips. However, little has empirically shown whether poor air quality indeed affects foraging performance (foraging trip duration) of honeybee. Here, we show apparent increases in the average duration of honeybee foraging during and after a heavy air pollution event compared with that of the pre‐event period. The average foraging duration of honeybees during the event increased by 32 min compared with the pre‐event conditions, indicating that 71% more time was spent on foraging. Moreover, the average foraging duration measured after the event did not recover to its pre‐event level. We further investigated whether an optical property (Depolarization Ratio, DR) of dominant PM in the atmosphere and level of air pollution (fine PM mass concentration) affect foraging trip duration. The result demonstrates the DR and fine PM mass concentration have significant effects on honeybee foraging trip duration. Foraging trip duration increases with decreasing DR while it increases with increasing fine PM mass concentration. In addition, the effects of fine PM mass concentration are synergistic with overcast skies. Our study implies that poor air quality could pose a new threat to bee foraging., The average foraging duration of honeybees during the event increased by 32 min compared with the pre‐event conditions, indicating that 71% more time is spent on foraging.

Although mechanical thrombectomy is a powerful predictor of stroke outcome, it induces vessel wall injury in the acute phase. This study aimed to analyze the degree and the condition of recovery of wall injury after the acute phase via angiography and histopathological analysis of autopsied canine models. Digital subtraction angiography (DSA) and embolization with autologous thrombus were performed in six canines. The model of arterial occlusion was effective in all target vessels. Mechanical thrombectomy was performed in completely occluded vessels using stent retriever. Follow-up angiographic and histopathologic evaluations were performed 1 month later. Complete recanalization using stent retriever was achieved in four cases. Slight residual vessel narrowing after recanalization and moderate narrowing was observed in one case each. Histopathological analysis showed that inflammation, hemorrhage, and device-induced medial injury were not observed in any of the cases. Severe intimal proliferation (grade 4), marked diffuse thrombosis (grade 4), and weak vascular endothelial cell loss (grade 1) were observed in one case and weak endovascular proliferation was observed in one case. Although successful complete recanalization was achieved with a single mechanical thrombectomy attempt and no change was observed in the follow-up DSA, special attention should be paid to postoperative follow-up, as device-induced intimal proliferation, diffuse thrombosis, and endothelial cell loss may remain after 1 month.

In this paper, we report on a new dielectric, a C60-containing block polyimide (PI-b-C60). This was realized by introducing C60 as pendent groups into a polymer backbone. When this dielectric was used in a non-contact mode triboelectric nanogenerator (TENG), it achieved high output power and reliable operation. Compared with perfluoroalkoxy alkane film-based TENGs, the TENG based on PI-b-C60 generated 4.3 times higher output power and a superior charge density of over 300 μC m−2 with a 3 times slower charge decay rate. These results are most likely due to the excellent charge-retention characteristics induced by the most negative electrostatic potential of C60 within the backbone, and these characteristics were confirmed by surface potential measurements. Furthermore, in the course of our work, two non-contact mode applications, a keyless electronic door lock system and a speed sensor with a tone wheel for a car, were developed. Without an ion injection process being needed, very sensitive and reliable operations of the speed sensor were successfully demonstrated, even under very humid conditions (∼99% RH).

This work introduces, for the first time, the energy harvesting performance of conjugated microporous polymers (CMPs) as tribo-positive materials for triboelectric nanogenerators (TENGs). Various nano or submicron CMP particles (CMP-X) were prepared by the Sonogashira coupling of 1,3,5-triethynylbenzene with 1,4-diiodoarenes. Optimized CMP-X nanoparticles in a polyurethane (PU) matrix showed excellent triboelectrification performance, displaying peak-to-peak voltages of up to 411 V and a maximum power density of 0.80 mW cm−2. Moreover, an optimized 5.0% CMP-H@PU-based TENG could be utilized as a power source for the charging of an electrolytic capacitor and for the operation of 100 LEDs.

The heating section of an annealing furnace is a plant that raises the temperature of steel strips to the desired target temperature to ensure that the strips achieve the desired material properties. Model predictive control (MPC) has been used to increase the temperature in previously published studies, because it reflects the geometrical and material characteristics of the strip. An accurate temperature predictive model for the annealing furnace is required for the optimization of the MPC. For a large and complex annealing furnace, nonlinear models from existing studies are computationally expensive. Therefore, we propose identification method of a linear low-order model, and then apply it to the MPC. In addition, we introduce parameter estimation and an adaptive observer for the estimation to address difficulties in identifying unknown parameters. To verify the identified model and adaptive observer-based MPC, control results from the tracking of target temperature are shown and analyzed through a simulation with conditions close to the actual operation conditions. Furthermore, the simulation results of the proposed method are compared with those of the PI controller and nonlinear MPC. The proposed method solves the problems caused by the massive computational complexity and absence of sensors. The proposed method allows for the accurate control of the temperature using MPC in various types of annealing furnaces.

Here, we demonstrate a dynamic perovskite device capable of converting mechanical energy into direct current (DC) electrical energy, combining two concepts: carrier generation from the triboelectric effect and carrier separation through band energy level difference. By analyzing and comparing different perovskite (FAPbI3, MAPbI3, MAPbBr3, PEA2PbI4, etc.) and charge transport layer (CTL) materials (spiro-MeOTAD, PTAA, TiO2, SnO2, etc.), the key rules for determining DC output and performances are identified: (1) a suitable band alignment (band position and bandgap) between perovskite and CTL can separate the carrier transfer; (2) a large difference in work function between two layers leads to high electrical potential difference; and (3) a high carrier concentration can enhance the DC power-generating performances. Furthermore, it is found that the light illumination acts as a stimulus to current output to a large extent, which is due to the coupling effect from triboelectric and photovoltaic effects. This study provides a set of key rules to explain the mechanism and to further improve the performance of the dynamic perovskite/CTL heterojunction.

Background: Endoscopic removal of large and thick-stalked pedunculated colonic polyps, often leads to massive hemorrhage. Several techniques to minimize this complication have not been widely adopted due to some caveats. In order to prevent postpolypectomy bleeding, we invented a novel technique to dissect long-stalked pedunculated colonic polyps using endoscopic band ligation (EBL) by laterally approaching the stalk. Methods: In this prospective single-center study, 17 pedunculated polyps in 15 patients were removed between April 2012 and January 2016. We targeted pedunculated polyps with a long stalk length (>10 mm) and a large head (>10 mm) located in the distal colon. After identifying lesions with a colonoscope, we reapproached the middle part of the stalk of the targeted polyp with an EBL-equipped gastroscope to ligate it. Snare polypectomy was performed just above the ligation site of the stalk. Results: EBL-assisted polypectomy removed all of the lesions successfully, which were confirmed pathologically. There was little technical difficulty associated with the endoscopic procedures, regardless of polyp size and stalk thickness, except for one case with a very large polyp that impeded the visualization of the ligation site. We observed a positive correlation between procedure time and the diameter of the head (spearman ρ = 0.52, P = 0.034). After dissection of the polyp, the EBL bands remained fastened to the dissected stalks in all cases. There was no complication associated with polypectomy for 1 month. Conclusion: EBL-assisted polypectomy is an easy, safe, and effective technique to remove long-stalked pedunculated colonic polyps without postpolypectomy bleeding.

This study aimed to investigate the effects of Judo athletes’ psychological function on sports coping skills through self-management: the moderated mediating effect of tension. A total of 124 participants (66 males and 58 females) were included, comprising high school students, college students, and judo team players (age 16 to 30, 20.51 ± 3.17) in the Republic of Korea. The psychological function was measured using the Profile of Mood Test, Athletes’ Self-Management Questionnaire, and Athletic Coping Skills Inventory-28. The results of the analysis of the moderating effect of the athlete’s self-management behavior showed that tension had a moderating effect on the relationship between the athlete’s self-management behavior and sports coping skills. The mediating effect analysis revealed a mediating effect of self-management behavior on the relationship between player vitality and sports coping skills. It was also confirmed that tension had a moderating effect on athletes’ self-management behavior and sports coping skills. Therefore, it was confirmed that the higher the self-management, the more moderated the mediating effect on sports coping skills. In conclusion, it was confirmed that psychological function affects sports coping skills, and thereby, the mediating effect of the athlete’s self-management behavior is regulated by tension. In future research, it will be necessary to study the sports coping ability and performance of judo athletes according to tension control.