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991.
Takahiro Kochi Yoki Nakamura Simeng Ma Kazue Hisaoka-Nakashima Dengli Wang Keyue Liu Hidenori Wake Masahiro Nishibori Masahiro Irifune Norimitsu Morioka 《Molecules (Basel, Switzerland)》2021,26(7)
Persistent pain following orofacial surgery is not uncommon. High mobility group box 1 (HMGB1), an alarmin, is released by peripheral immune cells following nerve injury and could be related to pain associated with trigeminal nerve injury. Distal infraorbital nerve chronic constriction injury (dIoN-CCI) evokes pain-related behaviors including increased facial grooming and hyper-responsiveness to acetone (cutaneous cooling) after dIoN-CCI surgery in mice. In addition, dIoN-CCI mice developed conditioned place preference to mirogabalin, suggesting increased neuropathic pain-related aversion. Treatment of the infraorbital nerve with neutralizing antibody HMGB1 (anti-HMGB1 nAb) before dIoN-CCI prevented both facial grooming and hyper-responsiveness to cooling. Pretreatment with anti-HMGB1 nAb also blocked immune cell activation associated with trigeminal nerve injury including the accumulation of macrophage around the injured IoN and increased microglia activation in the ipsilateral spinal trigeminal nucleus caudalis. The current findings demonstrated that blocking of HMGB1 prior to nerve injury prevents the onset of pain-related behaviors, possibly through blocking the activation of immune cells associated with the nerve injury, both within the CNS and on peripheral nerves. The current findings further suggest that blocking HMGB1 before tissue injury could be a novel strategy to prevent the induction of chronic pain following orofacial surgeries. 相似文献
992.
Layer transfer of single-crystalline SiC based on layer splitting and wafer bonding on an alternate substrate is a viable approach to fabricate SiC power devices at a lower cost. Dependence of implantation-induced surface blistering and exfoliation of thin layers, on the implantation parameters and subsequent annealing conditions, for large area exfoliation of 4H-SiC have been studied. We report the optimization of the annealing process (one-step or two-step) and annealing parameters like temperature and time to achieve large area exfoliation of SiC. Using the Föppl-von Karman (FvK) theory, the pressure inside the blister cavities and implantation-induced stress inside the damage region have been studied. We deduce that pressure inside the blister depends primarily on the blister size. HRXRD analysis has been used to determine the strain relaxation behavior as a function of annealing conditions. Raman spectroscopy and STEM measurements revealed the formation of defects inside the material due to ion implantation. AFM, Nomarski, and SEM were used to measure the size and depth details of the blisters as a function of annealing temperature and time. We have successfully exfoliated large area (up to 500 μm) in a two-step annealing process. The results reported in this paper are useful for SiC layer transfer on an arbitrary substrate by the Smart Cut process. 相似文献
993.
Guangyu Dong Haifeng Lu Zhijun Wu Robert Dibble Liguang Li 《Proceedings of the Combustion Institute》2019,37(4):4865-4873
Ion current sensing has the potential to become a promising combustion diagnostic technique for mass productive engines. In this paper, the effect of electric fields on ion current signals measured from a series of methane/air flames in a constant volume combustion chamber (CVCC) is investigated both experimentally and numerically. Based on simultaneous flame Schlieren imaging and ion current measurement, the relation between the flame/electrodes contact area and the ion current signal waveform is explored under different electric field configurations. A CFD model, which incorporates flame plasma hydrodynamics, neutral/charged species reaction kinetics and ion-electric field interactions, is constructed. The effect of the electric field on the ion distribution and the charged species flux are analyzed, and the signal amplitude and timing are well predicted under the equivalence ratio range of Ф?=?0.7–1.1. Besides, the behavior of electrons, which is normally neglected in previous studies, is also analyzed in this work. The results show that it will affect the signal as well. The electron produced in the flame front zone can hardly diffuse into the pre-flame zone (<?350?K) even its mobility is 3-4 order higher than those of the positive ions. Therefore, the anode of the ion probe, which placed in the pre-flame zone, cannot detect the ion current signal until it contacts the flame front. 相似文献
994.
995.
Manfred Sager 《Monatshefte für Chemie / Chemical Monthly》1987,118(1):25-29
A rapid method for the determination of fluorine in various matrices of geochemical and environmental interest is described. After fusion with NaOH, the sample is dissolved by means of tiron (= pyrocatechol-3,5-disulfonic acid, disodium salt), which acts both as buffer substance and as superior masking agent for cations exhibiting strong complexes with fluoride, e.g. Al, Fe, Ti etc. The final determination is done by means of the fluoride sensitive electrode without further separation.The applicability of the method has been checked for various silicates, bauxite, phosphates, soils, coal and plant material. A detection limit of 10 µg/g can be achieved, which is sufficient in many cases. The overall precision is better than ±10%.Dedicated to Prof. Dr.K. L. Komarek on occasion of his 60th birthday. 相似文献
996.
I. E. Tyschenko L. Rebohle R. A. Yankov W. Skorupa A. Misiuk G. A. Kachurin 《Journal of luminescence》1998,80(1-4):229-233
We have studied the influence of the hydrostatic pressure during annealing on the intensity of the visible photoluminescence (PL) from thermally grown SiO2 films irradiated with Si+ ions. Post-implantation anneals have been carried out in an Ar ambient at temperatures Ta of 400°C and 450°C for 10 h and 1130°C for 5 h at hydrostatic pressures of 1 bar–15 kbar. It has been found that the intensity of the 360, 460 and 600 nm PL peaks increases with rising hydrostatic pressure during low-temperature annealing. The intensity of the short-wavelength PL under conditions of hydrostatic pressure continues to rise even at Ta=1130°C. Increasing Ta leads to a shift in the PL spectra towards the ultraviolet range. The results obtained have been interpreted in terms of enhanced, pressure-mediated formation of ≡Si–Si≡ centres and small Si clusters within metastable regions of the ion-implanted SiO2. 相似文献
997.
Summary A group of 17 β-carbolines was studied in HPLC and TLC systems in order to predict their partition coefficients (log P values).
On account of the basic or acid character of some of these compounds, an ion pairing system gave the best results. Both HPLC
and TLC data were comparable for log P prediction but severe pH conditions required the use of TLC plates. Retention data
are quantitatively related to lipophilicity (expressed as the Hansch constant) and polarity (as the inductive constant) of
the solute molecule. 相似文献
998.
We discuss the origins and the effects of mobility fluctuations of rigid, globular macromolecules on a solution's electrophoretic light scattering spectrum. Assuming a dilute solution, a modified van Hove self-correlation function is calculated via van Kampen's time-ordered cumulant method and the results are compared with less rigorous approaches. The consequences of generalizing to dynamic external fields are briefly considered. 相似文献
999.
由Nd:YAG激光器三倍频,输出波长为λ=355 nm(28 169 cm~(-1))的激光光解NO_2分子产生的氧原子,通过共振增强多光子电离(REMPI resonance enhanced multiphoto ionization)及飞行时间(TOF time of flight)质谱技术,获得了自旋-轨道精细能级分辨的氧原子O(2 p~3P_J~″=2,1,0)离子谱.氧离子信号强度与UV电离激光能量(λ≈226 nm)之间的关系能用三次方曲线很好拟合,它表明光解产物氧原子是通过(2+1)多光子吸收过程而被电离的.由离子信号得到的氧原子基态三个自旋-轨道支能级布居比f_1=I(~3P_1)/I(~3P_2)与fo=I(~3P_0)/I(~3P_2)分别为0.54±0.09和0.20±0.04,并且在不同的光解激光能量下其布居比保持不变.这一比值与统计分布计算的值为0.6和0.2一致(即统计分布~3P_2:~3P_1:~3P_0=1:0.6:0.2).这是由于样品(NO_2)在较低的压力下(1.33×10~(-4)Pa)和极短的光解-电离时间范围内(10~(-8)s),产物O(~3P_J~″)支能级间几乎不可能发生碰撞能量转移,因此,氧原子三个自旋-轨道角动量分裂能级布居O(~3P_J~″=2,1,0)是统计分布的. 相似文献
1000.
Molecular mobility of oxygen, O2, and nitrogen, N2, in Carbon Molecular Sieves, CMS, was investigated using the Frequency Response, FR, technique to identify mass-transfer mechanisms and related kinetic time constants. The FR data showed that O2 mobility in four types of CMS was dominantly controlled by surmounting surface-barrier resistances, whereas the mobility of both O2 and N2 in pellets of a fifth CMS type obeyed the Fickian diffusion model. Temperature and pressure dependences of surface-barrier penetration time constants were obtained for O2 and N2 in several of those CMS materials. The kinetic time constants of surface-barrier penetration were related to Langmuir-type rate constants, which indicates that kinetic behavior of O2 therein could also be interpreted in terms of a Langmuir-kinetics equation. 相似文献