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The present study aimed to evaluate the performance of automated skeletal maturation assessment system for Fishman’s skeletal maturity indicators (SMI) for the use in dental fields. Skeletal maturity is particularly important in orthodontics for the determination of treatment timing and method. SMI is widely used for this purpose, as it is less time-consuming and practical in clinical use compared to other methods. Thus, the existing automated skeletal age assessment system based on Greulich and Pyle and Tanner-Whitehouse3 methods was further developed to include SMI using artificial intelligence. This hybrid SMI-modified system consists of three major steps: (1) automated detection of region of interest; (2) automated evaluation of skeletal maturity of each region; and (3) SMI stage mapping. The primary validation was carried out using a dataset of 2593 hand-wrist radiographs, and the SMI mapping algorithm was adjusted accordingly. The performance of the final system was evaluated on a test dataset of 711 hand-wrist radiographs from a different institution. The system achieved a prediction accuracy of 0.772 and mean absolute error and root mean square error of 0.27 and 0.604, respectively, indicating a clinically reliable performance. Thus, it can be used to improve clinical efficiency and reproducibility of SMI prediction.

The stability of graphene dispersions in water is of both scientific and technological significance. We studied the dispersion stability of electrochemically exfoliated graphene in an aqueous medium to minimize the strong aggregation tendency, within a short period, of graphene prepared in various electrolytes. This study focused on increasing the dispersion stability of graphene and finding the reason for its poor dispersion stability. The residual electrolyte trapped in the graphene layers was difficult to be removed from electrochemically exfoliated graphite and caused a significant aggregation. The stability and dispersion concentration can be improved by removing the trace amount of aqueous electrolyte. The aggregation mechanism of graphene in aqueous media is proposed and discussed in detail.

The electrochemical exfoliation of graphene is a very useful technique to prepare highly conductive graphene with a low defect level. However, low dispersion stability is a barrier to this process being used to prepare graphene directly in a wide range of applications. Even though the dispersion stability and concentration of graphene are important, the reasons for the lower dispersion stability and lower concentration of electrochemically exfoliated graphene have not yet been clarified. In this study, we identified that the strong electrostatic attractive interaction between charged ions from electrolytes at the interfaces of graphene layers substantially deteriorated the dispersion stability. Both the stability and the concentration of graphene dispersions were substantially enhanced upon removal of the residual electrolytes from the organic solvents used in this study.

Tumor interstitial pressure is a fundamental feature of cancer biology. Elevation in tumor pressure affects the efficacy of cancer treatment and results in the heterogenous intratumoral distribution of drugs and macromolecules. Monoclonal antibodies (mAb) play a prominent role in cancer therapy and molecular nuclear imaging. Therapy using mAb labeled with radionuclides-also known as radioimmunotherapy (RIT)-is an effective form of cancer treatment. RIT is clinically effective for the treatment of lymphoma and other blood cancers; however, its clinical use for solid tumor was limited because their high interstitial pressure prevents mAb from penetrating into the tumor. This pressure can be decreased using anti-cancer drugs or additional external therapy. In this paper, we reviewed the intratumoral pressure using direct tumor-pressure measurement strategies, such as the wick-in-needle and pressure catheter transducer method, and indirect tumor-pressure measurement strategies via magnetic resonance.

Announced as one of the top 10 research breakthroughs in 2016, perovskite solar cells (PSC) have advanced rapidly as an established photovoltaic technology. The power conversion efficiency (PCE) of PSCs has increased quickly from 3.8% to 23.7% within a period of just 7 years. This very high PCE has been achieved by using perovskite compounds with lead (Pb) as the divalent metal ion. However, for further scale-up and commercialization, the toxicity of Pb has been identified as one of the key drawbacks for this technology. Numerous avenues for development of lead-free low-toxicity perovskite absorbers have been pursued. The unclear effect of using low-toxicity materials on optimal performance with suitable characteristics has motivated the writing of this review. Results from low-toxicity perovskite solar cells utilizing partial or complete substitution of the Pb2+ cation as the absorber layer are discussed in detail. Moreover, we discuss the limitations of low-toxicity absorber materials. This review summarizes the key points of film quality control, degradation effect, Pb replacement suitability, and photovoltaic performance of reported low toxicity alternate perovskite absorbers for PSCs.

In this work, a simple and one-step solvothermal method has been developed for directly growing three-dimensional flower-like cobalt sulfide (CoS) on the fluorine-doped tin oxide coated glass substrate (FTO) for the counter electrode in the dye sensitized solar cell. The electroctalytic activity of the CoS@FTO towards the I3− to I− reduction exhibited almost similar electrocatalytic properties to the Pt-based counter electrode. The dye-sensitized solar cell (DSSC) assembled with CoS@FTO counter electrode attained almost similar photovoltaic performance (5.64%) to that of the DSSC with Pt@FTO counter electrode (5.9%) under 1 sun illumination. The adhesion stability of the CoS deposited at FTO was also studied using strong adhesive tape test, and the results show that after the strong adhesive tape test, the CoS@FTO retained almost 95% of the coating. The similar and comparative performance of the CoS@FTO to the Pt@FTO may be due to the high surface area originating from the 3D flower-like morphology, and the excellent electrocatalytic activity of the CoS.

Thin film of metallic Cu nanoparticles was synthesized by a one-pot chemical reduction method at ambient temperature. Cu(II) acetate monohydrate and hydrazine monohydrate were used as precursor and reducing agent without additional surfactants to form uniform layer of Cu nanoparticle layer on a glass substrate (Cu/G). The XRD and the effectiveness of the electrocatalytic and catalytic properties of the Cu/G have been applied for an amperometric detection of glucose and for the chemical reduction of 4-nitrophenol. The former exhibited the detection limit as low as 2.47 μM with a linear range of 0.01–0.2 mM, while the latter showed the efficient catalytic activity with a high rate constant of 0.503/min. The current method suggested in this work might be useful for the fabrication of glass-based Cu nanoparticles electrodes for industrial and biomedical applications.

Compared with solid scintillators, liquid scintillators have limited capability in dosimetry and radiography due to their relatively low light yields. Here, we report a new generation of highly efficient and low-cost liquid scintillators constructed by surface hybridisation of colloidal metal halide perovskite CsPbA3 (A: Cl, Br, I) nanocrystals (NCs) with organic molecules (2,5-diphenyloxazole). The hybrid liquid scintillators, compared to state-of-the-art CsI and Gd2O2S, demonstrate markedly highly competitive radioluminescence quantum yields under X-ray irradiation typically employed in diagnosis and treatment. Experimental and theoretical analyses suggest that the enhanced quantum yield is associated with X-ray photon-induced charge transfer from the organic molecules to the NCs. High-resolution X-ray imaging is demonstrated using a hybrid CsPbBr3 NC-based liquid scintillator. The novel X-ray scintillation mechanism in our hybrid scintillators could be extended to enhance the quantum yield of various types of scintillators, enabling low-dose radiation detection in various fields, including fundamental science and imaging., Optics: Hybrid liquid scintillator with enhanced light output A hybrid liquid scintillator could be used in low-dose radiation detectors for use in imaging applications and scientific research. Highly sensitive X-ray detection is increasingly being used in industrial and military applications and for fundamental scientific research. Although liquid scintillators are more resilient to damage from exposure to intense radiation than crystalline or plastic scintillators, they have relatively low density and low radioluminescence quantum yields, both of which are critical for achieving high resolution and contrast in X-ray imaging. Now, a team of Korean researchers led by Hyunsik Im from Dongguk University has created a liquid scintillator detector made from colloidal perovskite metal halide nanocrystals and organic molecules with a significantly enhanced quantum yield. The novel device could see use in a wide range of X-ray technologies that require high-performance detectors and imagers.

In this study, nickel hydroxide nanoparticles (NPs) decorated with nitrogen doped multiwalled carbon nanotubes (N-MWCNT) hybrid composite was synthesized by thermal reduction process in the presence of cetyl ammonium bromide (CTAB) and urea. The as-synthesized Ni(OH)2@N-MWCNT hybrid composite was characterized by FTIR, Raman, XRD, BET, BJH and FE-TEM analyses. These prepared porous carbon hybrid composite materials possessed high specific surface area and sheet like morphology useful for active electrode materials. The maximum specific capacitance of Ni(OH)2@N-MWCNT hybrid nanocomposite in the two electrode system showed 350 Fg−1 at 0.5 A/g,energy density ~43.75 Wkg−1 and corresponds to power density 1500 W kg−1 with excellent capacity retention after 5000 cycles. The results suggest that the prepared two-dimensional hybrid composite is a promising electrode material for electrochemical energy storage applications.

The Korean traditional hot sauce gochujang has been reported to have biological activities. Different kinds of gochujang products were prepared based on combinations of a fungal rice koji with two kinds of bacterial soybean mejus. Diets that included gochujang products were fed to rats and anti-obesity effects were investigated. Gochujang products reduced body weight gains, epididymal fat weights, and triglyceride levels in the serum and the liver. Effects were exerted by the diet that included the non-fermented gochujang mixture, increased using a fungal rice koji, and further enhanced using a bacterial soybean meju. Dietary effects were apparently induced via inhibition of the lipogenic enzymes fatty acid synthase, malic enzyme, and lipoprotein lipase by gochujang products in epididymal adipose tissues, and inhibition of glucose-6-phosphate dehydrogenase in the liver. High levels of capsaicin and genistein in gochujang products are considered to contribute to anti-obesity effects.

Hypoglycemic and hypolipidemic effects of ramie leaf ethanol extract (RLE) on C75BL/KsJ-db/db mice were determined. The db/db mice were divided into diabetic control group (C), two experimental groups orally treated with low dose (200 mg/k, RLEL) and high dose (400 mg/kg, RLEH) of RLE. After 6 weeks, fasting blood glucose, serum insulin, and glycosylated hemoglobin levels decreased in RLE groups compared to those in the control group. The glucose levels in the oral glucose tolerance test and area under the curve for glucose in the RLE groups were also significantly lower than those in the control group (p

In dye-sensitized solar cells, highly ordered TiO2 nanotube arrays as a photoelectrode have higher charge collection efficiencies than a nanoparticle-based structure due to their faster charge percolation and slower recombination of electrons. Highly ordered TiO2 nanotube arrays were grown by anodic oxidation of 0.5-mm-thick titanium foil. To increase the conversion efficiency of dye-sensitized solar cells with TiO2 nanotube arrays, the surface of the TiO2 nanotube arrays was modified by zinc oxide thin films. The ZnO thin film was formed by atomic layer deposition. The thin film was conformal on the inner and outer walls of TiO2 nanotube arrays. ZnO thin film improved the short circuit current (Jsc) and open circuit voltage (Voc) due to increasing specific surface area from particulates of ZnO thin film and increasing the surface charge induced from the isoelectric point. The power conversion efficiency of dye-sensitized solar cells with ZnO thin film on 4.5-μm-thick TiO2 nanotube arrays was 1.43%. Microstructure and phase were observed by scanning electron microscopy, x-ray diffractometry, and transmission electron microscopy.

This study compared the quality characteristics between meat ball products in domestic market. Five types of meat ball products(T1, T2, T3, T4 and T5) were purchased in domestic market. In terms of the chemical composition, meat ball products ranged 53.92~63.45% in moisture contents. In terms of quality characteristics, T2 showed a significantly higher pH value and cooking loss than the others (p

The current study was carried out to determine the effects of Kohlrabi (Brassica oleracea var. gongylodes) on proliferation and differentiation of pig preadipocytes and 3T3-L1 cells. Pig preadipocytes were isolated from the backfat of the new-born pigs. Twenty-four hours after seeding, the cells were washed with DMEM/F-12 (designated day 0). To measure the cell proliferation, the cells were treated with 25 ng/ml and 100 ng/ml ethanol extracts of Kohlrabi (peel and flesh) for two days (day 0 ~ 2). To measure differentiation, the cells were treated with Kohlrabi for two days (day 0 ~ 2) and cell differentiation was measured on day 6. Twenty-five ng/ml and 100 ng/ml of Kohlrabi peel decreased proliferation of pig preadipocytes by 4.59% and 17.7%, respectively, compared with the control and Kohlrabi flesh by 11.4% and 19.2%, respectively. However, Kohlrabi did not inhibit cell differentiation. To measure the effects of Kohlrabi on proliferation and differentiation of 3T3-L1 cells, the cells were treated with Kohlrabi for two days in culture, like pig preadipocytes. Kohlrabi (both peel and flesh) did not show any effects on cell proliferation and differentiation. In summary, the results of the current study showed that Kohlrabi decreased proliferation of pig preadipocytes, but no inhibitory effects on differentiation of the cells. Kohlrabi had no effects on proliferation and differentiation of 3T3-L1 cells.

We report findings related to a solid-state thin film supercapacitors (TFSCs) fabricated with ruthenium oxide electrodes and hydrogen doped tantalum oxide electrolyte in order to investigate a feasibility for solid oxide thin film electrolyte in all solid state micropower sources with hydrogen conducting electrolyte. The TFSCs in this study has a cell structure of RuO2/Ta2O5/RuO2/Pt. Radio frequency, off-axis r.f. sputtering deposition of a Ta2O5 thin film was performed on the bottom amorphous RuO2 electrode which was deposited by an on-axis direct current reactive sputtering, within hydrogen atmosphere to enhance the concentration of mobile proton (H+) ions. Scanning electron microscopy (SEM) measurements reveal that the RuO2/Ta2O5/RuO2 hetero-interfaces have no inter-diffusion problems. Room temperature charge–discharge measurements with constant current clearly reveal typical supercapacitor behavior. Also, owing to the fast diffusion of H+ ions within the Ta2O5 lattice without any structural deterioration, the capacitance per volume of RuO2/Ta2O5/RuO2/Pt TFSCs was maintained to be constant during above 800 cycles. This result indicated that the solid oxide thin film has possibility as the solid proton conducting electrolyte for all solid state micropower sources.

The purpose of this study was to evaluate tibiofemoral kinematics after double-bundle anterior cruciate ligament (ACL) reconstructions and compare them with those of successful single-bundle reconstructions and contralateral normal knees using open MR images. We obtained MR images based on the flexion angle without weight-bearing, from 20 patients with successful unilateral single-bundle (10 patients) and double-bundle (10 patients) ACL reconstructions with tibialis anterior allografts and a minimum 1-year follow-up. The MR images of the contralateral uninjured knees were used as normal controls. Sagittal images of the mid-medial and mid-lateral sections of the tibiofemoral compartments were used to measure the translation of the femoral condyles relative to the tibia. The mean translations of the medial femoral condyles on the tibial plateaus during knee joint motion showed no significant differences among normal, single-bundle, and double-bundle ACL reconstructed knees (all p>0.05). The mean translations of the lateral femoral condyles showed a significant difference between normal and single-bundle reconstructed knees, or between single-bundle and double-bundle reconstructed knees (p

Tributyltin chloride (TBTC) at concentrations of 0.5-1.0 microM inhibits dopamine biosynthesis in PC12 cells. In this study, the effects of TBTC on L-3,4-dihydroxyphenylalanine (L-DOPA)-induced cytotoxicity in PC12 cells were investigated. TBTC at concentrations up to 1.0 microM neither affected cell viability, nor induced apoptosis after 24 or 48 h in PC12 cells. However, TBTC at concentrations higher than 2.0 microM caused cytotoxicity through an apoptotic process. In addition, exposure of PC12 cells to non-cytotoxic (0.5 and 1.0 microM) or cytotoxic (2.0 microM) concentrations of TBTC in combination with L-DOPA (20, 50 and 100 microM) resulted in a significant increase in cell loss and the percentage of apoptotic cells after 24 or 48 h compared with TBTC or L-DOPA alone. The enhancing effects of TBTC on L-DOPA-induced cytotoxicity were concentration- and treatment time-dependent. These data demonstrate that TBTC enhances L-DOPA-induced cytotoxicity in PC 12 cells.

Nitrogen fixation is essential for the synthesis of many important chemicals (e.g., fertilizers, explosives) and basic building blocks for all forms of life (e.g., nucleotides for DNA and RNA, amino acids for proteins). However, direct nitrogen fixation is challenging as nitrogen (N₂) does not easily react with other chemicals. By dry ball-milling graphite with N₂, we have discovered a simple, but versatile, scalable and eco-friendly, approach to direct fixation of N₂ at the edges of graphene nanoplatelets (GnPs). The mechanochemical cracking of graphitic C--C bonds generated active carbon species that react directly with N₂ to form five- and six-membered aromatic rings at the broken edges, leading to solution-processable edge-nitrogenated graphene nanoplatelets (NGnPs) with superb catalytic performance in both dye-sensitized solar cells and fuel cells to replace conventional Pt-based catalysts for energy conversion.

The communication energy consumption in a data-gathering tree depends on the number of descendants to the node of concern as well as the link quality between communicating nodes. In this paper, we examine the network lifetime of several localized tree construction schemes by incorporating the communication overhead due to imperfect link quality. Our study is conducted based on empirical data obtained from a real-world deployment, which is further supported by mathematical analysis. For the case of a sparse node density, a large network size and a low link threshold, we show that the link-quality-based scheme provides the longer network lifetime than the minimum hop routing schemes. We present a lower bound on the number of nodes per hop and the link quality threshold of the radio range, which work together to result in a superior localized scheme for longer network lifetime.