An Effective Approach of Teeth Segmentation within the 3D Cone Beam Computed Tomography Image Based on Deformable Surface Model

In order to extract the pixels of teeth from 3D Cone Beam Computed Tomography (CBCT) image, in this paper, a novel 3D segmentation approach based on deformable surface mode is developed for 3D tooth model reconstruction. Different forces are formulated to handle the segmentation problem by using different strategies. First, the proposed method estimates the deformation force of vertex model by simulating the deformation process of a bubble under the action of internal pressure and external force field. To handle the blurry boundary, a “braking force” is proposed deriving from the 3D gradient information calculated by transforming the Sobel operator into three-dimension representation. In addition, a “border reinforcement” strategy is developed for handling the cases with complicate structures. Moreover, the proposed method combines affine cell image decomposition (ACID) grid reparameterization technique to handle the unstable changes of topological structure and deformability during the deformation process. The proposed method was performed on 510 CBCT images. To validate the performance, the results were compared with those of two other well-studied methods. Experimental results show that the proposed approach had a good performance in handling the cases with complicate structures and blurry boundaries well, is effective to converge, and can successfully achieve the reconstruction task of various types of teeth in oral cavity

Enhancement Mode Ga2O3 Field Effect Transistor with Local Thinning Channel Layer

β−Ga2O3 field−effect transistors (FETs) were fabricated with and without local thinning to change the threshold voltage. A 220 nm Ga2O3 layer was mechanically exfoliated from a Cr−doped gallium oxide single crystal. Approximately 45 nm Ga2O3 was etched by inductively coupled plasma to form the local thinning. The threshold voltage of the device with etched local thinning increased from −3 V to +7 V compared to the unetched device. The effect of the local thinning was analyzed by device simulation, confirming that the local thinning structure is an effective method to enable enhancement−mode Ga2O3 FETs

Development and Validation of an HPLC-ESI/MS/MS Method for the Determination of Amoxicillin, Its Major Metabolites, and Ampicillin Residues in Chicken Tissues

A method for the simultaneous analysis of amoxicillin (AMO), amoxicillin metabolites, and ampicillin residues in edible chicken muscle, liver, and kidney samples via high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI/MS/MS) was developed and verified. The extraction and purification procedures involved the extraction of the sample using a liquid-liquid extraction method with acetonitrile to eliminate the proteins. The chicken tissue extract was then injected directly onto an HPLC column coupled to a mass spectrometer with an ESI(+) source. The HPLC-ESI/MS/MS method was validated according to specificity, sensitivity, linearity, matrix effects, precision, accuracy, decision limit, detection capability, and stability, as defined by the European Union and Food and Drug Administration. The linearity was desirable, and the determination coefficients (r2 values) ranged from 0.9968 and 0.9999. The limits of detection and limits of quantification were 0.10–2.20 μg/kg and 0.30–8.50 μg/kg, respectively. The decision limits were 57.71–61.25 μg/kg, and the detection capabilities were 65.41–72.50 μg/kg, and the recoveries of the four target analytes exceeded 75% at the limits of quantification and exceeded 83% at 25, 50, and 100 μg/kg (n = 6 at each level), confirming the reliability of this method for determining these analytes and providing a new detection technology. For real sample analysis, this experiment tested 30 chicken tissue samples, only one chicken muscle, liver, and kidney sample were contaminated with 5.20, 17.45, and 7.33 μg/kg of AMO values, respectively, while other target compounds were not detected in the 30 tested chicken tissue samples

pH-Responsive Low-Power Upconversion Based on Sandwichlike Palladiumphthalocyanine and Rhodamine B

Sandwhichlike palladiumphthalocyanine was found to possess highly efficient NIR triplet sensibilization with an increasing of ligand number, due to the triplet energy level (<i>E</i>_T) enhancing and the triplet lifetime (³τ₀) prolonging and resulting in efficient triplet–triplet energy transfer (TTT). Also, rhodamine B (RhB) was found to act as reactive triplet acceptor that emits red-to-yellow upconversion when doped with sandwhichlike complex. By tuning pH value, the three-layered phthalocyanine/RhB system presents so far the highest red-to-yellow upconversion efficiency (Φ_UC) as large as 10.5% (λ_ex = 655 nm, 1W·cm^–2), which has provided a simple approach to develop not only the new-type highly efficient NIR sensitizers but also the TTA-UC supported pH response applied in biomedicine

Structural features and optical properties of a carbazole-containing ethene as a highly emissive organic solid

info:eu-repo/semantics/publishe

High pO₂ Flux Growth and Characterization of NdNiO₃ Crystals

Single crystals of the perovskite nickelate NdNiO3 with dimensions of up to 50 μm on edge have been successfully grown using the flux method at a temperature of 400 °C and oxygen pressure of 200 bar. The crystals were investigated by a combination of techniques, including high-resolution synchrotron X-ray single-crystal and powder diffraction and physical property measurements such as magnetic susceptibility and resistivity. Resistivity measurements revealed a metal-insulator transition (MIT) at TMIT~180 K with apparent thermal hysteresis; however, no superlattice peaks or peak splitting below TMIT, which corresponds to a structural transition from Pbnm to P21/n, was observed. The successful growth of NdNiO3 crystals at relatively low temperatures and oxygen pressure provides an alternative approach for preparing single crystals of interesting perovskites such as RNiO3 (R = Sm-Lu) and parent phases of superconducting square planar nickelates

Synthesis and Electrochromic Properties of New Terpyridine–Triphenylamine Hybrid Polymers

Six metallic terpyridine-based complexes MLn (M = Ru, Fe; <i>n</i> = 1–3) with two triphenylamine sides have been designed and synthesized with the purpose of both providing four terminal active sites for the following electrochemical polymerization and prolonging the electrochromic memory time and the durability. Within the voltage range from 0 to 2 V, the obtained electro-polymerized films of polymers (p-MLn) present reversibly distinguishable color change (i.e., from orange red to yellow (or tan) for polymers p-RuLn and from purple to blue for polymers p-FeLn), strongly suggesting that the electrochromic colors could be tuned with the binding metal ion. Interestingly, the electrochromic memory ability and long-term stability (durability) have been found to depend on not only the rigidity but also the length of these triphenylamine-based ligands. It is interpreted that triphenylamine-based ligands with the rigid and short conjugation can promote intramolecular charge transfer from the triphenylamine group (D) to the metallic terpyridine (A), which certainly will effectively stabilize the oxidation state (i.e., Ru³⁺, Fe³⁺) of metallic terpyridine and remarkably enhance the memory ability and durability of electrochromic film