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Titanium nitride (TiN) is a metal-like refractory material that can be used as a substitution for metals in many applications. In this paper, we report the use of an ultra-thin TiN film in the Salisbury screen structure to spectral selectively absorb visible light for forming an optical color filter. The ultra-thin TiN film functions as a partial reflector as well as a protection capping layer in the structure. Spectral selective perfect absorption color filters with TiN-ZnO-Al multilayer films were fabricated and characterized.
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Rosmarinic acid (RosA) is a water-soluble polyphenol, which can be isolated from many herbs such as orthosiphon diffuses and rosmarinus officinalis. Previous studies have shown that RosA possesses various biological properties. In this study, we investigate the anti-osteoarthritic effects of RosA in rat articular chondrocytes. Chondrocytes were pre-treated with RosA, followed by the stimulation of IL-1ß. Real-time PCR and Western blot were performed to detect the expression of matrix metalloproteinase (MMP)-1, MMP-3 and MMP-13. Nitric oxide and PGE2 production were measured by Griess reagent and enzyme-linked immunosorbent assay (ELISA). The expression of mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) was also investigated by Western blot analysis. We found that RosA down-regulated the MMPs expression as well as nitric oxide and PGE2 production in IL-1ß-induced chondrocytes. In addition, RosA inhibited p38 and JNK phosphorylation as well as p65 translocation. The results suggest that RosA may be considered a possible agent in the treatment of OA.
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Condrócitos/metabolismo , Cinamatos/farmacologia , Depsídeos/farmacologia , Dinoprostona/metabolismo , Regulação para Baixo/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Óxido Nítrico/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrócitos/enzimologia , Ciclo-Oxigenase 2/metabolismo , Ativação Enzimática/efeitos dos fármacos , Interleucina-1beta/farmacologia , Metaloproteinases da Matriz/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação/efeitos dos fármacos , Ratos Sprague-Dawley , Via de Sinalização Wnt/efeitos dos fármacos , Ácido RosmarínicoRESUMO
To explore a new surgical approach for chin augmentation using a prosthesis with 3 intraoral vertical incisions whereby placement of the prosthesis is more convenient and accurate, with fewer postoperative complications. Following the anatomic characteristics of the chin, a bilateral mucosal vertical incision and a median observation incision are made. The V-shaped mark on the upper side of the prosthesis can be seen through the observation incision after it is placed from the lateral incision into the predesigned compartment. The incision can be sutured if there is no bleeding in the operation area. Surgery performed in all 19 patients with mild microgenia with 6 to 12 months of follow-up resulted in satisfactory chin and face shape without any complications. The application of this novel method can correct McCarthy type I microgenia with more accurate positioning, less possibility of bilateral sideways and/or up/down movement, and fewer complications.
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Queixo/cirurgia , Mentoplastia/métodos , Adolescente , Adulto , Queixo/anormalidades , Estética , Feminino , Mentoplastia/efeitos adversos , Humanos , Masculino , Complicações Pós-Operatórias , Próteses e Implantes , Adulto JovemRESUMO
OBJECTIVE: To evaluate the influence of polymorphisms in nucleotide excision repair (NER) and homologous recombination repair (HRR) pathways on the development of osteosarcoma patients. METHODS: Genotypes of ERCC1 rs11615 and rs3212986, ERCC2 rs1799793 and rs13181, NBN rs709816 and rs1805794, RAD51 rs1801320, rs1801321 and rs12593359, and XRCC3 rs861539 were conducted by Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP) assay. RESULTS: Total 148 osteosarcoma patients and 296 control subjects were collected from Taizhou First People's Hospital. Conditional logistic regression analyses found that individuals carrying with GA+AA genotype of ERCC2 rs1799793 and GC+CC genotype of NBN rs1805794 were significantly associated with increased risk of osteosarcoma, and the ORs(95%CI) were 1.58(1.03-2.41) and 2.66(1.73-4.08), respectively. We found that GA+AA genotype of ERCC2 rs1799793 or GC+CC genotype of NBN rs1805794 were associated with an increased risk of osteosarcoma in females, with ORs(95%CI) of 2.42(1.20-4.87) and 2.01(1.07-4.23), respectively. CONCLUSION: Our results suggest that ERCC2 rs1799793 and NBN rs1805794 polymorphisms were associated with an increased risk for osteosarcoma, which suggests that NER and HRR pathways modulate the risk of developing osteosarcoma.
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BACKGROUND: Osteosarcoma (OS) is a highly invasive primary malignancy of the bone that is common in children and adolescents. MicroRNAs (miRNAs) are novel diagnostic and predictive biomarkers for cancers. The miRNA miR-3195 is aberrantly expressed in multiple types of tumors. However, the expression levels and biological functions of miR-3195 in OS remain unclear. METHODS: Two Gene Expression Omnibus (GEO) datasets (GSE69470 and GSE16088) were used to analyze differentially expressed miRNAs and mRNAs in osteosarcoma cell lines and OS tissues. Quantitative RT-PCR was used to detect the expression levels of miR-3195 and the SRY-box transcription factor 4 (SOX4) mRNA in OS tissues and cell lines. The relationship between miR-3195 and the 3'-upstream region (3'-UTR) in the SOX4 mRNA (predicted through bioinformatics) was analyzed using Pearson's correlation analysis and confirmed by a dual-luciferase reporter gene experiment. Cell counting kit-8 assays, colony formation assays, flow cytometry, wound healing assays, transwell assays, and western blotting were performed to explore the effects of miR-3195 levels on SOX4 affected OS cell biological behavior. RESULTS: Our results revealed that miR-3195 was the most down-regulated miRNA and SOX4 was the most up-regulated mRNA by Bioinformatic analysis. It was further confirmed miR-3195 had low expression, and SOX4 had high expression levels in clinical OS tissue samples; the expression levels of both genes were negatively correlated with each other in OS tissues. Overexpression of miR-3195 in OS cell lines significantly inhibited cell proliferation, migration, and invasiveness, while promoting apoptosis; all these effects were reversed by increasing SOX4 expression levels. We also found that miR-3195 could directly bind with the SOX4 gene and down-regulate SOX4 expression. CONCLUSIONS: miR-3195 can modulate proliferation, migration, invasiveness, and apoptosis in OS cells by regulating the SOX4 gene. Thus, the miR-3195/SOX4 signaling may be a novel therapeutic target in OS treatment.
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Neoplasias Ósseas , MicroRNAs , Osteossarcoma , Adolescente , Criança , Humanos , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/metabolismo , Osteossarcoma/patologia , RNA Mensageiro/genética , Fatores de Transcrição SOXC/genéticaRESUMO
IN THE TITLE COMPOUND [SYSTEMATIC NAME: 1(2),1(5)-dibromo-5(2),5(5)-dimethoxy-2,7-dithia-1,5(1,4)-dibenzenaoctaphane], C(18)H(18)Br(2)O(2)S(2), the dihedral angle between the aromatic rings is 0.6â (2)° and their centroid separation is 3.251â (2)â Å, indicating that a trans-annular π-π interaction occurs. The dimeth-oxy and dibromo substituents are located at crossed positions because of the electronic and the steric nature of the substituents.
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We study the Landau-level spectrum of a monolayer black phosphorus under an exponentially decaying magnetic field along one spatial dimension. The results show that unlike the case in a constant magnetic field, the number of Landau levels in the inhomogeneous magnetic field is finite, and the Landau-level structure of the system is strongly dependent on the inhomogeneity of the magnetic field. In particular, the crossing of some Landau levels apparently occurs, and the accidental degeneracy points between the levels for the conduction and valence bands are highly anisotropic due to the anisotropic effective masses in monolayer black phosphorus. The above unique characteristics of the Landau-level structure in an exponentially decaying magnetic field could be directly confirmed by the magneto-absorption and transport measurements.
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We study the tunnel magnetoresistance (TMR) and spin transport in ferromagnetic graphene junctions composed of ferromagnetic graphene (FG) and normal graphene (NG) layers. It is found that the TMR in the FG/NG/FG junction oscillates from positive to negative values with respect to the chemical potential adjusted by the gate voltage in the barrier region when the Fermi level is low enough. Particularly, the conventionally defined TMR in the FG/FG/FG junction oscillates periodically from a positive to negative value with increasing the barrier height at any Fermi level. The spin polarization of the current through the FG/FG/FG junction also has an oscillating behavior with increasing barrier height, whose oscillating amplitude can be modulated by the exchange splitting in the ferromagnetic graphene.
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We propose an Aharonov-Bohm interferometer with a quantum dot molecule embedded in one arm and study the spin-dependent transport due to the interplay of the Fano and Rashba effects. It is found that the Fano resonances of the molecular states exhibit opposite directions of asymmetric tails with one being from peak to dip and the other from dip to peak. The Rashba spin-orbit interaction induces a spin-dependent phase, making the two Fano dips overlap for one spin component of conductance and the two Fano peaks overlap for the other spin component. Both the direction and magnitude of the spin polarization of the conductance are easily controlled and manipulated through the Rashba parameter and interdot coupling strength. In addition, spin accumulations with opposite signs can be generated in the two quantum dots.
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BACKGROUND: The revision rate of articular surface replacement (ASR) implants continues to rise in China because of metal debris. However, there are few reports on the clinical results of ASR implants with prolonged follow-up time in China. This study investigated the clinical outcomes and the risk factors of revision surgery in patients with ASR implants. METHODS: In total, 74 patients (74 hips) who underwent primary total hip arthroplasty (THA) with ASR implants over the past 4 to 10 years were retrospectively analyzed. Relevant clinical, radiographic, and biochemical data were examined. RESULTS: The average follow-up time was 88.46 (range 23-114) months, and the ASR implants of 18 hips (24.3%) were revised. Patients who received revision surgery had worse joint function with significantly lower Harris Hip Score and Western Ontario and McMaster Universities index than non-revision patients (61.11 ± 6.68 vs 85.30 ± 9.16, p < 0.001; 61.00 ± 3.83 vs 79.04 ± 14.49, p < 0.001; respectively). Higher acetabular abduction angle and serum Co and Cr concentration were significantly relevant to worse joint function as measured by HSS (p = 0.018, 0.009, 0.043, respectively). ROC curve analysis was applied to categorize the optimal cutoff values of acetabular abduction angle and serum Cr and Co concentration for revision surgery, which were settled as 47.80°, 98.44 µg/L, and 6.95 µg/L, respectively. Overall survival of the prostheses with high acetabular abduction angle (> 47.80°, HR = 70.145, 95% CI 1.558-3158.213, p = 0.029), high serum Cr concentration (98.44 µg/L, HR = 58.956, 95% CI 1.294-2685.203, p = 0.036), and high serum Co concentration (> 6.95 µg/L, HR = 179.511, 95% CI 2.360-13656.941, p = 0.019) decreased significantly than the lower groups. CONCLUSIONS: Evaluation of the DePuy ASR XL articulation demonstrated increased rates of revision following a longer follow-up period. High acetabular abduction angle and serum Cr and Co concentration correlated with worse clinical outcomes and high revision rate. Therefore, we advocate that patients with DePuy ASR XL implants be followed up more closely than those with other implants, especially with high acetabular abduction angle and serum Cr or Co concentration.
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Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/tendências , Prótese de Quadril/tendências , Adulto , Idoso , Artroplastia de Quadril/normas , China/epidemiologia , Feminino , Seguimentos , Prótese de Quadril/normas , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
The surface passivation of Ge(100) and Ge(111) anodes in Ge-air batteries with different doping types and concentrations is analyzed by density function theory (DFT) calculations. Compared with Ge(111) anodes, the surface passivation is restrained on Ge(100) anodes as they have larger binding energies with GeO2 layers. Meanwhile, doping would hinder the formation of a GeO2 layer on Ge anodes, especially for p-type doping, like B. The dissimilarities of the electrostatic potential differences and projected local density of states between the p-type Ge(100)/GeO2 and Ge(111)/GeO2 also reveal the origins of their distinct performances in Ge-air batteries. Furthermore, the I-V curves show that the Ge(100)/GeO2/Ge(100) device has a higher current than the Ge(111)/GeO2/Ge(111) device. This work would help to fundamentally comprehend the different electrochemical properties of Ge-air batteries with different orientations and doping and provide guidelines for the design of Ge anodes in Ge-air batteries.
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Analytic treatment and Monte Carlo simulations are used to study the effective potential between two spheres in a suspension of rods whose ends can adhere to the surface of the spheres. When only one end of each rod is adhesive the effective potential changes from being attractive to repulsive with enhancing the adherence, but when both ends of each rod are adhesive the effective potential is not a monotonic function of the distance between the two spheres for strong adherence. As the adhesive strength is fixed, the range of the effective potential will increase with increasing the length of the rods. When the adhesive range is much smaller than the diameter of the spheres, its influence on single end adhesion is approximately linear and on two end adhesion is about quadratic. Our results are qualitatively consistent with a recent experimental work.
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One-atom-thick silicene is a silicon-based hexagonal-lattice material with buckled structure, where an electron fuses multiple degrees of freedom including spin, sublattice pseudospin and valley. We here demonstrate that a valley-selective spin filter (VSSF) that supports single-valley and single-spin transport can be realized in a silicene field effect transistor constructed of an npn junction, where an antiferromagnetic exchange field and a perpendicular electric field are applied in the p-doped region. The nontrivial VSSF property benefits from an electrically controllable state of spin-polarized single-valley Dirac cone. By reversing the electric field direction, the device can operate as a spin-reversed but valley-unreversed filter due to the dependence of band gap on spin and valley. Further, we find that all the possible spin-valley configurations of VSSF can be achieved just by tuning the electric field. Our findings pave the way to the realization of completely independent electrical control of spin and valley in silicene circuits.
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Based on the three-order-parameter model, we investigate the orientational order transition of striped patterns in microphase structures of diblock copolymer-homopolymer mixtures in the presence of periodic oscillatory particles. Under suitable conditions, although the macrophase separation of a system is almost isotropic, the microphase separation of the system will be significantly perturbed by the oscillatory field, and composition fluctuations are suppressed anisotropically. The isotropy of the microphase will be broken up. By changing the oscillatory amplitude and frequency, we observe the orientational order transition of a striped microphase structure from the isotropic state to a state parallel to the oscillatory direction, and from the parallel state to a state perpendicular to the oscillatory direction. We examine, in detail, the microstructure and orientational order parameter as well as the domain size in the process of orientational order transition under the oscillatory field. We study also how the microphase structure changes with the composition ratio of homopolymers and copolymers in mixtures. The results suggest that our model system may provide a simple way to realize orientational order transition of soft materials.
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Motivated by the fact that a population of competing agents never set up a true stationary distribution, we propose a theory of evolution kinetics for complex adaptive systems. The formula derived for the survival probability is used to describe different phases in the population evolution when the prize-to-fine ratio as well as time changes. A kinetic phase diagram is obtained to show the phase boundaries for the self-segregating region, the intermediate region, and the clustering region. The kinetic evolutionary equations of strategy distribution are also established and used to give the root-mean-square separation of strategy distribution. It is revealed that the rootstock of the phase transitions is ascribed to the cooperation and competition among agents with different gene values for a limited resource.
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Adaptação Fisiológica/fisiologia , Evolução Biológica , Comportamento Competitivo , Teoria dos Jogos , Modelos Biológicos , Modelos Estatísticos , Dinâmica Populacional , Animais , Simulação por Computador , Ecossistema , Humanos , Cinética , Transição de Fase , Crescimento Demográfico , Seleção Genética , Análise de Sobrevida , Taxa de SobrevidaRESUMO
We study the unequal kinetic temperatures in two-dimensional binary granular mixtures heated by vertical vibrations under gravity by molecular dynamics simulations. By introducing several variable parameters describing particle and composition properties of mixtures, the coexistence of two different kinetic temperatures for the two components is exhibited. In dilute situations, our numerical results confirm the overall experimental measurements by Feitosa and Menon recently [Phys. Rev. Lett. 88, 198301 (2002)]. For example, the temperature ratio along the vertical direction is constant in the bulk of a system, and is insensitive to external driving or relative concentration of the two components, but mainly influenced by their masses. However, outside of the dilute situations, especially as the number density becomes high enough where the spatial and momentum correlations become salient, the ratio profiles show some different characteristics. Generally, the plateau shape along the vertical direction is broken, and instead, a saddlelike shape appears. Furthermore, the physical implications are discussed.
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A Bernal-stacked hexagonal boron-nitride (h-BN) bilayer is a two-dimensional polar crystal. Within the tight-binding approximation, we investigate the band structure of a gated h-BN bilayer by analyzing the density of states and the behavior of the charge transfer. We find that the bandgaps of the h-BN bilayer vary asymmetrically under two opposite biases due to asymmetric changes of the interlayer and intralayer polarities. We also find that the bias-driven net charge transfer between layers can be up to 0.2 electron per unit cell. Under the bias along one direction, the system exhibits quantum phase transitions from a semiconductor to a semimetal and then to a semiconductor again, whereas under the reverse bias, the system is always semiconducting. Besides, asymmetric Landau levels under opposite biases arise in the presence of a magnetic field. Moreover, dispersive edge states are found to exist in the bulk bandgap for an h-BN bilayer nanoribbon under the bias along one direction, which does not happen when the bias is reversed. All these properties of h-BN bilayers are measurable in transport experiments.
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Compostos de Boro/química , Elétrons , Nanoestruturas/química , Teoria Quântica , Campos Magnéticos , Transição de Fase , Semicondutores , Propriedades de SuperfícieRESUMO
The spatially separated electron-hole pair condensation and Coulomb drag effect are studied theoretically in a graphene double layer. The main research results are presented as follows: we derive a critical average spacing of particles for the pair condensation to start at zero temperature, which is determined by the permittivity and thickness of the dielectric film between the two sheets of the graphene double layer; we obtain the phase diagram of condensates by introducing the ground-state fidelity, which accurately differentiates the Bose-Einstein condensate, Bardeen-Cooper-Schrieffer state, and their crossover; we confirm that the superfluid portion decreases the drag conductivity for a given gate voltage at finite temperatures; we find there exists a minimum drag conductivity by increasing the gate voltage, which results from the combined effect of the longitudinal conductivity in each graphene layer and superfluid density. The last result is especially useful for detecting the pair condensation experimentally.
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To show the specific behavior of Dirac fermions in a quasi-periodic structure, we investigate the electronic properties in a deterministic Thue-Morse graphene superlattice. Our main findings include the following. (i) Unlike conventional Schrödinger electrons, quasi-periodic features such as the striking self-similarity and trifurcation in the transmission spectrum can be manifested only at oblique incidence. (ii) In the vicinity of the usual Dirac point, extra Dirac points emerge; their locations are dependent merely on the second generation of the Thue-Morse structure and the number is double that in the periodic graphene superlattice. (iii) A classification is given about the wavefunctions in the Thue-Morse structure which are transformed from the critical states into extended ones at the Dirac points. (iv) The electrons can transmit perfectly at the extra Dirac points, and such a collimation supplies a convenient way to experimentally detect the numbers and the locations of the extra Dirac points. These exotic electronic properties in the aperiodic graphene superlattices may facilitate some applications in graphene-based electronics.
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Two dithia[3.3]paracyclophane-bridged bimetallic ruthenium acetylide complexes 2 and 3, in which the upper deck of the cyclophanes were assembled with naphthalenyl and anthracenyl rings, have been designed and synthesized. X-ray crystal structures of 2 and 3 show that there are effective transannular ππ interactions between the two rings in the cyclophane unit. Electrochemistry studies revealed that the successive introduction of naphthalenyl and anthracenyl rings reduced the thermodynamic stability of the corresponding mixed-valence states of 2 and 3. Radical cations and dications of complexes 2 and 3 were generated after the addition of 1.0 or 2.0 equivalents of ferrocenium hexafluorophosphate ([FcH][PF6]). The ν(C≡C) of radicals 2+ and 3+ shift 86 nm and 88 nm in contrast to 2 and 3, respectively. UV-Vis-NIR spectra of 2+ and 3+ exhibited three enveloped transitions in the NIR (10,0004000 cm(−1)) range. DFT studies showed that the compositions of the FMOs of 2 and 3 are more naphthalenyl and anthracenyl in character than the upper deck of complex 1. Spectroscopy and DFT studies indicated that the influence of transannular ππ interactions on the electronic transitions is more pronounced than in complex 1.