骨骼从生理学上讲是在成骨细胞所介导的骨形成和破骨细胞介导的骨吸收之间达到动态平衡的一个状态。以上两个过程均受到细胞因子和生长因子的精确调控。近年来,由骨保护素(osteoprotegerin,OPG)、核因子-κB受体活化因子配体(receptor a...骨骼从生理学上讲是在成骨细胞所介导的骨形成和破骨细胞介导的骨吸收之间达到动态平衡的一个状态。以上两个过程均受到细胞因子和生长因子的精确调控。近年来,由骨保护素(osteoprotegerin,OPG)、核因子-κB受体活化因子配体(receptor activator of NF-κB ligand,RANKL)、核因子-κB受体活化因子(receptor activator of NF-κB,RANK)3个隶属于肿瘤坏死因子家族的细胞因子组成OPG/RANKL/RANK系统的发现,使得在骨骼生理研究领域取得了重大突破。随着对OPG/RANKL/RANK系统研究的不断深入,发现该系统可为口腔医学领域中的多个学科提供有益的思路。本文就OPG/RANKL/RANK系统及其在口腔颌面组织中表达的相关研究进展作一综述。展开更多
核因子-κB受体活化因子配体(receptor activator of Nuclear factor-kappa B Ligand,RANKL)、核因子-κB受体活化因子(receptor activator of nuclear factor-kappa B,RANK)、骨保护素(osteoprotegerin,OPG)作为肿瘤坏死因子家族的成员...核因子-κB受体活化因子配体(receptor activator of Nuclear factor-kappa B Ligand,RANKL)、核因子-κB受体活化因子(receptor activator of nuclear factor-kappa B,RANK)、骨保护素(osteoprotegerin,OPG)作为肿瘤坏死因子家族的成员,通过RANKL/RANK/OPG信号通路调节破骨细胞发生及成熟,调控骨代谢,其表达水平直接影响骨质代谢与重塑,现被广泛研究。RANKL/RANK/OPG通路在口腔颌面部形成及改建过程中发挥了关键作用,直接或间接反映出口腔骨破坏类疾病的发生与发展状态。该通路的失衡往往伴随RANKL的增加和(或)OPG的减少,RANKL/OPG的比值影响破骨细胞的成熟及功能,但部分疾病中相关因子的表达水平存在争议,且尚无能应用于临床疾病诊疗的阈值。本文就RANKL/RANK/OPG信号通路调节机制及其在牙周炎、种植、牙齿发育、正畸、颌面部骨缺损修复与再生等口腔相关领域的研究现状进行综述,以进一步探讨口腔中骨代谢及骨破坏类疾病的调节机制,并评价相关因子作为生物标志物的诊断和预后潜力,以期指导临床诊疗及探寻可能的免疫调节靶点。展开更多
Based on vibration analysis, single-layered graphene sheet （SLGS） with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysuppo...Based on vibration analysis, single-layered graphene sheet （SLGS） with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysupported configuration. Based on the nonlocal plate the- ory which incorporates size effects into the classical theory, closed-form expressions lot the frequencies and relative fre- quency shills of SLGS-based mass sensor are derived using the Galerkin method. The suggested model is justified by a good agreement between the results given by the present model and available data in literature. The effects of tem- perature difference, nonlocal parameter, the location of the nanoparticle and the number of nanoparticles on the relative frequency shift of the mass sensor are also elucidated. The obtained results show that the sensitivity of the SLGS- based mass sensor increases with increasing temperature difference.展开更多
Quantum chemical calculations on some possible equilibrium geometries of C24O2 isomers derived from C24 （D6） and C24O have been performed using density functional theory （DFT） method. The geometric and electronic ...Quantum chemical calculations on some possible equilibrium geometries of C24O2 isomers derived from C24 （D6） and C24O have been performed using density functional theory （DFT） method. The geometric and electronic structures as well as the relative energies and thermal stabilities of various C24O2 isomers at the ground state have been calculated at the B3LYP/6-31G（d） level of theory. And the 1,4,2,5-C24O2 isomer was found to be the most stable geometry where two oxygen atoms were added to the longest carbon-carbon bonds in the same pentagon from a thermodynamic point of view. Based on the optimized neutral geometries, the vertical ionization potential and vertical electron affinity have been obtained. Meanwhile, the vibrational frequencies, IR spectrum, and 13C chemical shifts of various C24O2 isomers have been calculated and analyzed.展开更多
Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Expo...Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Exposure to the magnetic field caused a reliable shift in the peak (longer) wave-length of ~10 nm for fluorescence emissions and a ~20% increase (~100 counts) in fluorescence intensity. Spectral analyses verified a shift of 5 and 10 nm, equivalent to ~1.5 × 10-20 J “periodicity” across the measured wavelengths, which could reflect a change in the an intrinsic energy as predicted by Del Giudice and Preparata and could correspond to two lengths of O-H bonds. Wrapping the water sample containers during exposure with copper foil, aluminum foil, or plastic altered these fluorescent profiles. The most conspicuous effect was the elimination of a ~280 nm peak in the UV-VIS emission spectra only for samples wrapped with copper foil but not aluminum or plastic. These results suggest that weak magnetic fields produce alterations in the water-ionic complexes sufficient to be reliably measured by spectrophotometry. Because the effect was most pronounced when the spring water was exposed in darkness and was not disturbed the role of thixotropic phenomena and Del Giudice entrapment of magnetic fields within coherent domains of Pollack virtual exclusion zones (EZ) may have set the conditions for subsequent release of the energy as photons.展开更多
The equilibrium geometries, energies, harmonic vibrational frequencies, and nucleus independent chemical shifts （NICS） of the new type sandwich structures [As4MAs4]^n- （M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt; n ...The equilibrium geometries, energies, harmonic vibrational frequencies, and nucleus independent chemical shifts （NICS） of the new type sandwich structures [As4MAs4]^n- （M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt; n = 0, 1 or 2） are investigated at the B3LYP level. All the [As4MAs4]^n- species adopt staggered （D4d） conformations as their stable structures and eclipsed （D4h） conformations as their transition states, and once the sandwich complexes are formed, the As4^2- square properties remain unchanged. The NICS calculation confirms that the complexes of Fe, Co, and Ni are aromatic with negative NICS values, and those of Ru, Rh, and lx exhibit slight aromaticity, while those of Pd, Os, and Pt show slight antiaromaticity.展开更多
The theory of chemical shift effect of substituent was applied to the assignment of the 13 C NMR spectra of the ethylene/propylene and ethylene/octene 1 copolymers. Using the parameters derived above a...The theory of chemical shift effect of substituent was applied to the assignment of the 13 C NMR spectra of the ethylene/propylene and ethylene/octene 1 copolymers. Using the parameters derived above and the DEPT technique, we then entirely assigned the 13 C NMR spectra of the ethylene/propylene/octene 1 terpolymers synthesized in the presence of the same heterogeneous supported Ziegler Natta catalyst, TiCl 4/MgCl 2/ i Bu 3Al. The present paper also covers the terpolymer composition and the monomer sequence distributions of a series of ethylene/propylene/octene 1 terpolymers.展开更多
Based on the structure of chute - feed and autoleveHer, an analysis of their working principle and the verification of their practical production results have been carried out. Finally, the future investigation direet...Based on the structure of chute - feed and autoleveHer, an analysis of their working principle and the verification of their practical production results have been carried out. Finally, the future investigation direetiom of chute - feed and card autuleveller are put forward.展开更多
For a backward shift invariant subspace N in H^2（Г^2）, the operators Sz and Sw on N are defined by Sz = PNTz｜N and Sw, = PNTw｜N, where PN is the orthogonal projection from L^2（Г^2） onto N. We give a characteri...For a backward shift invariant subspace N in H^2（Г^2）, the operators Sz and Sw on N are defined by Sz = PNTz｜N and Sw, = PNTw｜N, where PN is the orthogonal projection from L^2（Г^2） onto N. We give a characterization of N satisfying rank [Sz, Sw^＊] = 1.展开更多
文摘骨骼从生理学上讲是在成骨细胞所介导的骨形成和破骨细胞介导的骨吸收之间达到动态平衡的一个状态。以上两个过程均受到细胞因子和生长因子的精确调控。近年来,由骨保护素(osteoprotegerin,OPG)、核因子-κB受体活化因子配体(receptor activator of NF-κB ligand,RANKL)、核因子-κB受体活化因子(receptor activator of NF-κB,RANK)3个隶属于肿瘤坏死因子家族的细胞因子组成OPG/RANKL/RANK系统的发现,使得在骨骼生理研究领域取得了重大突破。随着对OPG/RANKL/RANK系统研究的不断深入,发现该系统可为口腔医学领域中的多个学科提供有益的思路。本文就OPG/RANKL/RANK系统及其在口腔颌面组织中表达的相关研究进展作一综述。
文摘核因子-κB受体活化因子配体(receptor activator of Nuclear factor-kappa B Ligand,RANKL)、核因子-κB受体活化因子(receptor activator of nuclear factor-kappa B,RANK)、骨保护素(osteoprotegerin,OPG)作为肿瘤坏死因子家族的成员,通过RANKL/RANK/OPG信号通路调节破骨细胞发生及成熟,调控骨代谢,其表达水平直接影响骨质代谢与重塑,现被广泛研究。RANKL/RANK/OPG通路在口腔颌面部形成及改建过程中发挥了关键作用,直接或间接反映出口腔骨破坏类疾病的发生与发展状态。该通路的失衡往往伴随RANKL的增加和(或)OPG的减少,RANKL/OPG的比值影响破骨细胞的成熟及功能,但部分疾病中相关因子的表达水平存在争议,且尚无能应用于临床疾病诊疗的阈值。本文就RANKL/RANK/OPG信号通路调节机制及其在牙周炎、种植、牙齿发育、正畸、颌面部骨缺损修复与再生等口腔相关领域的研究现状进行综述,以进一步探讨口腔中骨代谢及骨破坏类疾病的调节机制,并评价相关因子作为生物标志物的诊断和预后潜力,以期指导临床诊疗及探寻可能的免疫调节靶点。
文摘Based on vibration analysis, single-layered graphene sheet （SLGS） with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysupported configuration. Based on the nonlocal plate the- ory which incorporates size effects into the classical theory, closed-form expressions lot the frequencies and relative fre- quency shills of SLGS-based mass sensor are derived using the Galerkin method. The suggested model is justified by a good agreement between the results given by the present model and available data in literature. The effects of tem- perature difference, nonlocal parameter, the location of the nanoparticle and the number of nanoparticles on the relative frequency shift of the mass sensor are also elucidated. The obtained results show that the sensitivity of the SLGS- based mass sensor increases with increasing temperature difference.
文摘Quantum chemical calculations on some possible equilibrium geometries of C24O2 isomers derived from C24 （D6） and C24O have been performed using density functional theory （DFT） method. The geometric and electronic structures as well as the relative energies and thermal stabilities of various C24O2 isomers at the ground state have been calculated at the B3LYP/6-31G（d） level of theory. And the 1,4,2,5-C24O2 isomer was found to be the most stable geometry where two oxygen atoms were added to the longest carbon-carbon bonds in the same pentagon from a thermodynamic point of view. Based on the optimized neutral geometries, the vertical ionization potential and vertical electron affinity have been obtained. Meanwhile, the vibrational frequencies, IR spectrum, and 13C chemical shifts of various C24O2 isomers have been calculated and analyzed.
文摘Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Exposure to the magnetic field caused a reliable shift in the peak (longer) wave-length of ~10 nm for fluorescence emissions and a ~20% increase (~100 counts) in fluorescence intensity. Spectral analyses verified a shift of 5 and 10 nm, equivalent to ~1.5 × 10-20 J “periodicity” across the measured wavelengths, which could reflect a change in the an intrinsic energy as predicted by Del Giudice and Preparata and could correspond to two lengths of O-H bonds. Wrapping the water sample containers during exposure with copper foil, aluminum foil, or plastic altered these fluorescent profiles. The most conspicuous effect was the elimination of a ~280 nm peak in the UV-VIS emission spectra only for samples wrapped with copper foil but not aluminum or plastic. These results suggest that weak magnetic fields produce alterations in the water-ionic complexes sufficient to be reliably measured by spectrophotometry. Because the effect was most pronounced when the spring water was exposed in darkness and was not disturbed the role of thixotropic phenomena and Del Giudice entrapment of magnetic fields within coherent domains of Pollack virtual exclusion zones (EZ) may have set the conditions for subsequent release of the energy as photons.
文摘The equilibrium geometries, energies, harmonic vibrational frequencies, and nucleus independent chemical shifts （NICS） of the new type sandwich structures [As4MAs4]^n- （M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt; n = 0, 1 or 2） are investigated at the B3LYP level. All the [As4MAs4]^n- species adopt staggered （D4d） conformations as their stable structures and eclipsed （D4h） conformations as their transition states, and once the sandwich complexes are formed, the As4^2- square properties remain unchanged. The NICS calculation confirms that the complexes of Fe, Co, and Ni are aromatic with negative NICS values, and those of Ru, Rh, and lx exhibit slight aromaticity, while those of Pd, Os, and Pt show slight antiaromaticity.
基金Supported by the Foundation of Educational Ministry of China.
文摘The theory of chemical shift effect of substituent was applied to the assignment of the 13 C NMR spectra of the ethylene/propylene and ethylene/octene 1 copolymers. Using the parameters derived above and the DEPT technique, we then entirely assigned the 13 C NMR spectra of the ethylene/propylene/octene 1 terpolymers synthesized in the presence of the same heterogeneous supported Ziegler Natta catalyst, TiCl 4/MgCl 2/ i Bu 3Al. The present paper also covers the terpolymer composition and the monomer sequence distributions of a series of ethylene/propylene/octene 1 terpolymers.
文摘Based on the structure of chute - feed and autoleveHer, an analysis of their working principle and the verification of their practical production results have been carried out. Finally, the future investigation direetiom of chute - feed and card autuleveller are put forward.
基金supported by Grant-in-Aid for Scientific Research (No. 16340037)Japan Society for the Promotion of Science
文摘For a backward shift invariant subspace N in H^2（Г^2）, the operators Sz and Sw on N are defined by Sz = PNTz｜N and Sw, = PNTw｜N, where PN is the orthogonal projection from L^2（Г^2） onto N. We give a characterization of N satisfying rank [Sz, Sw^＊] = 1.
