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1.
J Prosthet Dent ; 2023 Dec 21.
Article En | MEDLINE | ID: mdl-38129258

STATEMENT OF PROBLEM: Although the emergence angle has been related to marginal bone loss, information regarding the relationship between the transmucosal configuration of a computer-aided design and computer-aided manufacturing (CAD-CAM) abutment at specific subgingival levels and the amount of marginal bone loss is lacking. PURPOSE: The purpose of this retrospective clinical study was to evaluate the influence of CAD-CAM abutment profile angles, measured at different subgingival positions, on the marginal bone loss of posterior single-tooth implant-supported restorations. MATERIAL AND METHODS: A total of 260 posterior single-tooth implant-supported restorations using CAD-CAM abutments were analyzed in 206 patients. All implants had internal conical seal connections with a platform-switched design. The following data were extracted using digital periapical radiography: emergence profile, profile angle at distance ranges of 0 to 1 mm, 1 to 2 mm, and 2 to 3 mm from the implant-abutment junction, and peri-implant marginal bone loss (MBL). The MBL was measured from the time of delivery of the restorations up to 7 years or more. A linear mixed model was applied to investigate whether there was a significant difference in MBL based on the emergence profile and time, followed by the Bonferroni correction post hoc test. A Pearson correlation analysis was used to analyze the correlation between the profile angle and MBL at each distance range. The cut-off points for each distance range were determined by using the c-index, and independent t tests were conducted based on these cut-off values to evaluate the statistical differences (α=.05 for all statistical analyses). RESULTS: The convex emergence profile exhibited greater MBL than the concave and straight profiles at each follow-up visit (P<.001). A significant correlation was found between the profile angle and MBL in the 0 to 1 mm, 1 to 2 mm distance ranges. However, no significant correlation was found between the profile angle and MBL in the 2 to 3 mm distance range (P>.05). The cut-off points were 34 degrees at the mesial and 28 degrees at the distal in the 0 to 1 mm range, and 33 and 20 degrees at the mesial and distal in the 1 to 2 mm range. CONCLUSIONS: The profile angle near the implant-abutment junction and the type of emergence profile of the CAD-CAM abutment were closely associated with MBL in implants with internal conical seal connection with a platform switch design.

2.
Micromachines (Basel) ; 13(8)2022 Aug 08.
Article En | MEDLINE | ID: mdl-36014198

Silicon displacement defects are caused by various effects. For instance, epitaxial crystalline silicon growth and ion implantation often result in defects induced by the fabrication process, whereas displacement damage is induced by terrestrial cosmic radiation. Clustered displacement damage reportedly reduces the on-state current (Ion) in ordinary MOSFETs. In the case of an extremely scaled device such as a nanosheet field-effect transistor (NS-FET), the impact of displacement defect size was analyzed on the basis of the NS dimensions related to the device characteristics. In this study, we investigated the effect of displacement defects on NS-FETs using technology computer-aided design; the simulation model included quantum transport effects. The geometrical conditions, temperatures, trap concentrations, and scattering models were considered as the variables for on-state current reduction.

3.
Healthcare (Basel) ; 9(6)2021 May 28.
Article En | MEDLINE | ID: mdl-34071674

This study aimed to investigate the effects of mindfulness-based mandala coloring made within nature on individuals with chronic widespread musculoskeletal pain (CWP). Thirty-six participants were randomly allocated. In the experimental group, identical interventions and procedures were administered for each experiment. The control group members were untreated and remained in an urban environment. Overall, the experiment showed significant improvements in tender points (f = 8.791, p = 0.006), total stress level (f = 14.570, p = 0.001), depressive symptoms (f = 15.205, p = 0.001), anger symptoms (f = 7.263, p = 0.011) and salivary cortisol (f = 10.619, p = 0.003) in the experimental group. The results reflect that MBMC within nature is effective in reducing pain, psychological stress responses, and cortisol levels in individuals with CWP. The positive results could be a product of the experimental design rather than the treatment itself. A rigorous experimental design provides better understanding of MBMC within nature.

4.
Nanotechnology ; 32(35)2021 Jun 09.
Article En | MEDLINE | ID: mdl-34038895

High energy and high flux protons are used in proton therapy and the impact of proton radiation is a major reliability concern for electronics and solar cells in low earth orbit as well as in the trapped belts. Carbon nanotubes (CNTs), due to their unique characteristics, have been considered for the construction of proton and other radiation sensors. Here, a single wall CNT based proton sensor was fabricated on FR4 substrate and its response to 150 MeV proton irradiation was studied. The change in the resistance of the nanotubes upon irradiation is exploited as the sensing mechanism and the sensor shows good sensitivity to proton radiation. Proton radiation induces dissociation of ambient oxygen, followed by the adsorption of oxygen species on the nanotube surface, which influences its electrical characteristics. Since the nanotube film is thin and the 150 MeV protons are expected to penetrate into and interact with the substrate, control experiments were conducted to study the impact on FR4 substrate without the nanotubes. The dielectric loss tangent or dissipation factor of FR4 increases after irradiation due to an increase in the cross-linking of the resin arising from the degradation of the polymer network.

5.
Sensors (Basel) ; 21(6)2021 Mar 10.
Article En | MEDLINE | ID: mdl-33801968

Field-effect transistor (FET)-based biosensors have garnered significant attention for their label-free electrical detection of charged biomolecules. Whereas conventional output parameters such as threshold voltage and channel current have been widely used for the detection and quantitation of analytes of interest, they require bulky instruments and specialized readout circuits, which often limit point-of-care testing applications. In this study, we demonstrate a simple conversion method that transforms the surface potential into an oscillating signal as an output of the FET-based biosensor. The oscillation frequency is proposed as a parameter for FET-based biosensors owing to its intrinsic advantages of simple and compact implementation of readout circuits as well as high compatibility with neuromorphic applications. An extended-gate biosensor comprising an Al2O3-deposited sensing electrode and a readout transistor is connected to a ring oscillator that generates surface potential-controlled oscillation for pH sensing. Electrical measurement of the oscillation frequency as a function of pH reveals that the oscillation frequency can be used as a sensitive and reliable output parameter in FET-based biosensors for the detection of chemical and biological species. We confirmed that the oscillation frequency is directly correlated with the threshold voltage. For signal amplification, the effects of circuit parameters on pH sensitivity are investigated using different methods, including electrical measurements, analytical calculations, and circuit simulations. An Arduino board to measure the oscillation frequency is integrated with the proposed sensor to enable portable and real-time pH measurement for point-of-care testing applications.


Biosensing Techniques , Electrodes , Transistors, Electronic
6.
Arch Plast Surg ; 48(1): 55-60, 2021 Jan.
Article En | MEDLINE | ID: mdl-33503745

BACKGROUND: In patients with congenital melanocytic nevus (CMN), single-stage removal of large lesions can be difficult because the high tension created by excising and repairing a large lesion may result in scar widening. Herein, we introduce a method to effectively excise lesions while minimizing scarring and compare its outcomes to those of existing surgical methods. METHODS: We compared patients who underwent surgery using the anchoring technique (n=42) or the conventional elliptical technique (n=36). One side of the lesion was removed via en bloc resection up to the superficial fascia. The other side of the lesion was removed via de-epithelialization. The de-epithelialized dermal flap was then fixed by suturing it to the superficial fascia on the opposite side. The length of the lesion's long axis and amount of scar widening were measured immediately after surgery and at 2, 6, and 12 months postoperatively. At 12 months, patients were assessed using the Patient and Observer Scar Assessment Scale. RESULTS: The lesion locations included the face, arms, legs, back, and abdomen. The anchoring method resulted in shorter and smaller scars than the conventional method. There were no cases of postoperative hematoma or wound dehiscence. Significant differences in postoperative scar widening were found in the arm and leg areas (P<0.05). CONCLUSIONS: The anchoring method introduced in this study can provide much better outcomes than the conventional method. The anchoring method is particularly useful for the removal of CMN around the joints or extremities, where the surgical site is subjected to high tension.

7.
Materials (Basel) ; 14(2)2021 Jan 09.
Article En | MEDLINE | ID: mdl-33435423

Supercapacitors prepared by printing allow a simple manufacturing process, easy customization, high material efficiency and wide substrate compatibility. While printable active layers have been widely studied, printable electrolytes have not been thoroughly investigated despite their importance. A printable electrolyte should not only have high ionic conductivity, but also proper viscosity, small particle size and chemical stability. Here, gel-polymer electrolytes (GPE) that are compatible with printing were developed and their electrochemical performance was analyzed. Five GPE formulations based on various polymer-conductive substance combinations were investigated. Among them, GPE made of polyvinylidene difluoride (PVDF) polymer matrix and LiClO4 conductive substance exhibited the best electrochemical performance, with a gravimetric capacitance of 176.4 F/g and areal capacitance of 152.7 mF/cm2 at a potential scan rate of 10 mV/s. The in-depth study of the in-plane solid-state supercapacitors based on various printed GPEs suggests that printable electrolytes provide desirable attributes for high-performance printed energy devices such as supercapacitors, batteries, fuel cells and dye-sensitized solar cells.

8.
Nanoscale Adv ; 3(6): 1725-1729, 2021 Mar 23.
Article En | MEDLINE | ID: mdl-36132552

A nanoscale field emission vacuum channel gated diode structure is proposed and a tungsten cathode with an umbrella-like geometry and sharp vertical edge is fabricated. The edge of the suspended cathode becomes the field emission surface. Unlike in the traditional transistor with the gate typically located between the source and the drain, the bottom silicon plate becomes the gate here and the anode terminal is located between the umbrella cathode and the gate. The fabricated devices show excellent diode characteristics and the gated diode structure is attractive for extremely low gate leakage.

9.
ACS Sens ; 5(4): 1028-1032, 2020 04 24.
Article En | MEDLINE | ID: mdl-32200620

An all three-dimensional (3D)-printed flexible ZnO ultraviolet (UV) photodetector is demonstrated, where the 3D-printing method is used not only for the electrode and photosensitive material but also for creating a substrate. An ultraflat and flexible substrate capable of serving as the backbone layer is developed using a water-dissolvable polymer layer for surface planarization. A two-layered printing followed by surface treatment is demonstrated for the substrate preparation. As mechanical support but flexible, a thick and sparse thermoplastic polyurethane layer is printed. On its surface, a thin and dense poly(vinyl alcohol) (PVA) is then printed. A precise control of PVA reflow using a microwater droplet results in a flexible and extremely uniform substrate. A Cu-Ag nanowire network is directly 3D printed on the flexible substrate for the conducting layer, followed by ZnO for the photosensitive material. Unlike the planar two-dimensional printing that provides thin films, 3D printing allows the electrode to have a step height, which can be made like a dam to accommodate a thick film of ZnO. Photosensitivity as a function of various ZnO thickness values was investigated to establish an optimal thickness for UV response. The device was also tested in natural sunlight along with stability and reliability.


Zinc Oxide/chemistry , Printing, Three-Dimensional , Ultraviolet Rays
11.
Adv Healthc Mater ; 9(4): e1901575, 2020 02.
Article En | MEDLINE | ID: mdl-31945277

Thermotherapy is an effective method for pain relief, recovery from injury, and general healthcare. The ordinary heat pad used for thermotherapy at home is not usually tailored to the individual but supplied in a few different pre-fixed sizes and shapes for mass marketing. A customized wearable heat pad often requires expert support. Herein, an instant, custom-fit, and on-demand heat pad for thermotherapy is demonstrated. The heater is directly printed using silver nanoparticle ink on an off-the-shelf medical grade tape by inkjet technology. By coating the tape with silica nanoparticles as ink-absorbing layer and chloride ions as chemical sintering agent, stable heater patterns are printed without the need for subsequent high temperature sintering process. A 3D scanner is used to acquire body information, and a customized heater is produced using the information. The printed heat pad is attached to the shoulder and the effect of thermotherapy is verified objectively through electroencephalography and subjectively through survey. This printed heat pad produced by simple and low-cost fabrication provides wearable medical devices for personal thermotherapy.


Hyperthermia, Induced , Metal Nanoparticles , Wearable Electronic Devices , Printing, Three-Dimensional , Silver
12.
Aesthetic Plast Surg ; 43(6): 1547-1552, 2019 12.
Article En | MEDLINE | ID: mdl-31468136

BACKGROUND: The differences between Caucasian and East Asian faces could lead to different age-related bony changes. We analyzed computed tomography (CT) scan images of East Asians to find objective differences in midface rejuvenation strategy between East Asians and Caucasians. METHODS: We reviewed 54 East Asian individuals' charts and facial CT images ranging in age-group: Group A (21-30 years), Group B (41-50 years), and Group C (61-70 years). No patients had congenital or acquired facial deformity and history of facial trauma. The anteroposterior length of the orbital roof and floor (LOR, LOF) and the angle of the anterior wall of the maxilla were recorded on parasagittal images through the midline of the orbit. RESULTS: The LORs at their midpoints showed significant differences between Groups A and B (p < 0.01). The LOFs were also significantly different between Groups A and B (p < 0.001). The difference in the angle between the anterior maxillary wall and the orbital floor was not significant between Groups A and B. The lengths between Groups B and C showed no significant differences. CONCLUSION: Our study demonstrated that the aging process in East Asians differs considerably from that in Caucasians, with characteristic significant changes in LOF and LOR. Since the aging process is different, the strategies to cope with aging should also differ. Volume restoration of the inferior orbital rim in the midface is one of the most important rejuvenation methods in East Asians. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Maxilla/diagnostic imaging , Orbit/diagnostic imaging , Rhytidoplasty/methods , Tomography, X-Ray Computed , Adult , Age Factors , Aged , Aging , Asian People , Cheek/diagnostic imaging , Asia, Eastern , Female , Humans , Male , Middle Aged , Rejuvenation , White People , Young Adult
13.
ACS Sens ; 4(4): 1097-1102, 2019 04 26.
Article En | MEDLINE | ID: mdl-30848593

A single walled carbon nanotube (SWCNT) based γ ray detector is demonstrated without a conventional scintillation mechanism. The change in the conductance of a two terminal SWCNT resistor in response to γ ray exposure is exploited as a sensing mechanism. Radiation-induced ambient oxygen dissociation and subsequent adsorption of oxygen species on the SWCNT surface alter its electrical properties. The responses to the total dose and dose rate are investigated along with the sensing mechanism. The detector showed good sensitivity to γ ray and a capability to distinguish radiation dose rates ranging from 2.4 to 16.4 R/min.


Gamma Rays , Nanotubes, Carbon/chemistry , Radiometry/methods , Adsorption , Electrochemical Techniques/instrumentation , Electrochemical Techniques/methods , Microcomputers , Ozone/chemistry , Radiometry/instrumentation
14.
Arch Craniofac Surg ; 20(2): 109-111, 2019 Apr.
Article En | MEDLINE | ID: mdl-30703866

Intravascular papillary endothelial hyperplasia or Masson's hemangioma is a rare vascular tumor. The reactive proliferation of endothelial cells in this disease mimics other benign or malignant vascular proliferation such as angiosarcoma or Kaposi's sarcoma. It is important to make an accurate distinction to avoid confusion with these malignant tumors. This would facilitate a proper diagnosis, which is essential so that the patient is not subjected to unnecessarily aggressive or inappropriate treatment.

15.
BMC Complement Altern Med ; 19(1): 15, 2019 Jan 10.
Article En | MEDLINE | ID: mdl-30630473

BACKGROUND: Asian traditional herbal remedies are typically a concoction of a major and several complementary herbs. While balancing out any adverse effect of the major herb, the complementary herbs could dilute the efficacy of the major herb, resulting in a suboptimal therapeutic effect of an herbal remedy. Here, we formulated Chung-Sang (CS) by collating five major herbs, which are used against inflammatory diseases, and tested whether an experimental formula composed of only major herbs is effective in suppressing inflammation without significant side effects. METHODS: The 50% ethanol extract of CS (eCS) was fingerprinted by HPLC. Cytotoxicity to RAW 264.7 cells was determined by an MTT assay and a flow cytometer. Nuclear NF-κB and Nrf2 were analyzed by western blot. Ubiquitinated Nrf2 was similarly analyzed following immunoprecipitation of Nrf2. Acute lung inflammation and sepsis were induced in C57BL/6 mice. The effects of eCS on lung disease were measured by HE staining of lung sections, a differential cell counting of bronchoalveolar lavage fluid, a myeloperoxidase (MPO) assay, a real-time qPCR, and Kaplan-Meier survival of mice. RESULTS: eCS neither elicited cytotoxicity nor reactive oxygen species. While not suppressing NF-κB, eCS activated Nrf2, reduced the ubiquitination of Nrf2, and consequently induced the expression of Nrf2-dependent genes. In an acute lung inflammation mouse model, an intratracheal (i.t.) eCS suppressed neutrophil infiltration, the expression of inflammatory cytokine genes, and MPO activity. In a sepsis mouse model, a single i.t. eCS was sufficient to significantly decrease mouse mortality. CONCLUSIONS: eCS could suppress severe lung inflammation in mice. This effect seemed to associate with eCS activating Nrf2. Our findings suggest that herbal remedies consisting of only major herbs are worth considering.


Anti-Inflammatory Agents/administration & dosage , NF-E2-Related Factor 2/immunology , Plant Extracts/administration & dosage , Pneumonia/drug therapy , Animals , Anti-Inflammatory Agents/isolation & purification , Drug Compounding , Humans , Lung/drug effects , Lung/immunology , Mice , Mice, Inbred C57BL , NF-E2-Related Factor 2/genetics , NF-kappa B/genetics , NF-kappa B/immunology , Neutrophil Infiltration/drug effects , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Pneumonia/genetics , Pneumonia/immunology , RAW 264.7 Cells
16.
Nanoscale Adv ; 1(8): 2990-2998, 2019 Aug 06.
Article En | MEDLINE | ID: mdl-36133608

A method to electrically induce memristor performance from inkjet-printed silver (Ag) nanoparticles is presented, which is effective on a specifically designed hourglass-shaped Ag metal device. Joule heating-induced oxidation in the bottleneck region, when applying a high current to the device, results in a metal-electrolyte-metal structure produced from just a single metal ink for the memristor operation. This electrically induced memristor shows a nonuniform dispersion of the Ag nanoparticles within the oxide electrolyte layer, depending on the bias polarity adopted during the initial metal rupture process. A versatile and useful range of controllable memristor behaviors, from volatile threshold switching to nonvolatile unipolar as well as bipolar resistive switching, are observed based on the reversible rejuvenation and rupture of the Ag nanofilaments according to the Ag cation migration within the oxide electrolyte. The interplay between the electric field induced redox reaction and thermal diffusion of the Ag nanoparticles constitutes the primary reason for the different switching behaviors, further supported by thermo-field simulation results. The bipolar switching memristor demonstrates reliable endurance even under harsh DC switching conditions with low power consumption compared with its unipolar switching operation. The observed range of controllable switching behavior can be exploited for future low power flexible memory, as a selector in crossbar memory architecture, synaptic learning, and others.

17.
J Nanosci Nanotechnol ; 19(3): 1626-1629, 2019 Mar 01.
Article En | MEDLINE | ID: mdl-30469234

Here in, properties of samarium-doped indium-tin-oxide (ITO:Sm) films deposited by DC-magnetron sputtering, and organic light-emitting devices (OLEDs) using an ITO:Sm film as an anode were investigated. The electrical resistivity of the ITO:Sm films increased with Sm doping. The work function of each ITO:Sm film (5.2-5.7 eV) was higher than that of an ITO film (4.8 eV). The crystal structure of the ITO:Sm films was In2O3-type when the doping ratio of Sm in the film was up to 5 at.%, and the structure was amorphous in more strongly samarium-doped films. The properties of the OLEDs were varied by the doping ratio of samarium in the ITO:Sm electrodes. The OLEDs with the ITO:Sm electrode exhibited higher efficiency than that of an ITO-based control device at the same current density.

18.
J Comput Assist Tomogr ; 43(1): 119-127, 2019.
Article En | MEDLINE | ID: mdl-30052618

OBJECTIVE: The aim of this study was to describe magnetic resonance imaging findings of newly categorized ovarian seromucinous tumors. METHODS: We retrospectively reviewed the images of 29 patients with seromucinous tumor for the following factors: size, configuration, signal intensity (SI), and accompanying ovarian endometriosis. RESULTS: Thirty-two tumors (17 benign, 7 borderline, 8 carcinoma) were found on computed tomography or magnetic resonance imaging. Their mean size was 11.4 cm. Benign tumors appeared as unilocular or multilocular cystic masses. Borderline tumors and carcinomas appeared as complex cystic-solid masses. T2-weighted SI of the solid portion was hyperintense in borderline tumors and intermediate in carcinomas. Endometriosis was present in 18 tumors, and hemorrhage (on images) in 20. CONCLUSIONS: The imaging features of seromucinous tumors varied by tumor type. More than half of tumors were accompanied by endometriosis. High T2-weighted SI of the solid portion could be a specific feature of borderline tumors. It is hard to differentiate seromucinous carcinomas from other endometriosis-related carcinomas.


Magnetic Resonance Imaging/methods , Neoplasms, Cystic, Mucinous, and Serous/diagnostic imaging , Ovarian Neoplasms/diagnostic imaging , Adult , Diagnosis, Differential , Female , Humans , Middle Aged , Ovary/diagnostic imaging , Retrospective Studies
19.
ACS Appl Mater Interfaces ; 10(46): 40198-40202, 2018 Nov 21.
Article En | MEDLINE | ID: mdl-30394726

A fabric-compatible UV sensor is presented using a cellulose-based thread coated with single-wall carbon nanotube ink. Two-terminal resistive responses of the thread were measured upon exposure to UV, and the effects of intensity, wavelength, and on/off cycling were studied. The sensor was tested in the field under direct sunlight, demonstrating practical usability for a wearable/flexible UV sensor system. The results here confirm the potential for an inexpensive wearable sensor in contrast to the conventional rigid and bulky solid-state detectors.

20.
Arch Plast Surg ; 45(6): 572-577, 2018 Nov.
Article En | MEDLINE | ID: mdl-30466238

BACKGROUND: Mandibular contouring surgery to produce a more slender and small face has become popular, especially in East Asia. Narrowing genioplasty should be simultaneously performed with mandibular angle resection to achieve satisfactory results. In Korea, T-genioplasty has been frequently performed for chin narrowing. The authors developed a new, safe, and reliable method, termed M-genioplasty, that can provide a more slender and attractive lower face. METHODS: From June 2013 to December 2017, 36 patients underwent M-genioplasty with mandibular angle resection for lower facial contouring. Horizontal and vertical osteotomies were performed obliquely. The resected bone segments were wedge-shaped. The remaining two bone segments were rotated and approximated centrally. The lateral mandible bony stepoff was trimmed off for mandibular angle resection. RESULTS: In all patients, the facial contour sufficiently improved, and most patients were satisfied with the outcome. No severe complications took place during postoperative follow-up. CONCLUSIONS: M-genioplasty can provide more mandibular angle resection and can create a more acute chin angle without bone resorption than other methods, including T-genioplasty. M-genioplasty with mandibular angle resection is a safer, more accurate, and more reliable method for lower facial contouring.

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