甲磺酸左氧氟沙星的药代动力学研究

用微生物法测定了ＭＳＡＬＶＬＸ在狗体内的药代动力学过程符合二室模型。４、８和１６ｍｇ／ｋｇ口服给药的Ｃｍａｘ分别为１．７３、２．８９和８．２８ｍｇ／Ｌ,ＡＵＣ值分别为１５．４３、３１．９５和７０．２ｍｇｈ／Ｌ,ＭＲＴ分别为６．９６、７．５８和６６２８ｈ。大鼠口服２０ｍｇ／ｋｇ的Ｃｍａｘ为２．８６ｍｇ／Ｌ,ｔ１／２β为２．２ｈ,ＡＵＣ为７．４ｍｇｈ／Ｌ,ＭＲＴ为３ｈ。大鼠口服后７２ｈ的尿中排泄率为４２％,而７２ｈ胆汁排泄率为３８．２％。     

Investigation of Structural,Physical, and Attenuation Parameters of Glass: TeO2-Bi2O3-B2O3-TiO2-RE2O3 (RE: La,Ce, Sm,Er, and Yb), and Applications Thereof

A novel series of glass, consisting of B₂O₃, Bi₂O₃, TeO₂, and TiO₂ (BBTT) containing rare earth oxide RE₂O₃, where RE is La, Ce, Sm, Er, and Yb, was prepared. We investigated the structural, optical, and gamma attenuation properties of the resultant glass. The optical energy bands, the linear refractive indices, the molar refractions, the metallization criteria, and the optical basicity were all determined for the prepared glass. Furthermore, physical parameters such as the density, the molar volume, the oxygen molar volume, and the oxygen packing density of the prepared glass, were computed. Both the values of density and optical energy of the prepared glass increased in the order of La₂O₃, Ce₂O₃, Sm₂O₃, Er₂O₃, and then Yb₂O₃. In addition, the glass doped with Yb₂O₃ had the lowest refractive index, electronic polarizability, and optical basicity values compared with the other prepared glass. The structures of the prepared glass were investigated by the deconvolution of infrared spectroscopy, which determined that TeO₄, TeO₃, BO₄, BO₃, BiO₆, and TiO₄ units had formed. Furthermore, the structural changes in glass are related to the ratio of the intensity of TeO₄/TeO₃, depending on the type of rare earth. It is also clarified that the resultant glass samples are good attenuators against low-energy radiation, especially those that modified by Yb₂O₃, which exhibited superior shielding efficiency at energies of 622, 1170, and 1330 keV. The optical and gamma ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optical fibers, laser solid material, and optical shielding protection.     

基于蒙特卡洛的中美药典含量均匀度检查法的比较研究

目的 利用蒙特卡洛方法比较研究中国药典和美国药典的含量均匀度检查法,并提出改进思路。方法 以含量均匀度检查法准确率为性能指标,采用蒙特卡洛方法模拟药品质量的变化,并进行模拟抽样检查,比较中美药典含量均匀度检查法的性能;通过中心复合实验设计,考察中美药典含量均匀度检查法的检查参数对准确率的影响。结果 在不同均值和标准差情况下,中美药典的检查准确率无显著差异;中心复合实验设计的结果表明,中美药典含量均匀度检查法的参数均可进一步优化,从而提高检查准确率。结论 中美药典含量均匀度检查法的准确率基本一致,提出了优化含量均匀度检查参数的新思路。     

OCT测量视网膜神经纤维层厚度及视盘参数在青光眼早期诊断中的应用及意义

目的探讨光学相干断层扫描仪(optical coherence tomography,OCT)测量视网膜神经纤维层(retinal nerve fiber layer,RNFL)厚度及视盘参数在青光眼早期诊断中的应用及意义。方法青光眼患者120例(192眼)分为早期青光眼组42例(66眼)、中期青光眼组46例(76眼)和晚期青光眼组32例(50眼),另设正常对照组50例(82眼),均采用Topcon 3D OCT检测RNFL厚度和视盘参数,计算各个参数的受试者工作特征曲线下面积(are aunder the receiver operating characteristi ccurve,AROC),并对检测结果进行比较分析。结果正常对照组、早期青光眼组、中期青光眼组和晚期青光眼组的平均RNFL厚度分别为(112.31±9.34)μm、(105.45±6.74)μm、(82.19±7.28)μm、(52.48±7.85)μm;与正常对照组比较,各青光眼组的RNFL厚度差异均有显著统计学意义(均为P<0.01);各青光眼组之间两两比较差异也均有显著统计学意义(均为P<0.01)。与正常对照组相比,各青光眼组的视盘面积无明显变化,差异均无统计学意义(均为P>0.05),而视杯面积、视杯容积、杯盘比、水平杯盘比和垂直杯盘比均显著增加,差异均有显著统计学意义(均为P<0.01);盘沿面积和盘沿容积均显著降低,差异均有显著统计学意义(均为P<0.01);各青光眼组间除视盘面积外,各参数差异也均有显著统计学意义(均为P<0.01)。在正常对照组与早期青光眼组和全部青光眼组之间,对于RNFL厚度来说,平均RNFL厚度的AROC值最大;对于视盘参数来说,杯盘比的AROC值最大。结论 RNFL厚度和视盘参数是早期诊断青光眼的敏感指标,OCT检测RNFL厚度和视盘参数有助于青光眼的早期诊断。     

Mechanical Properties and Failure Behavior of Dry and Water-Saturated Foliated Phyllite under Uniaxial Compression

Phyllite is widely distributed in nature, and it deserves to be studied considering rock engineering applications. In this study, uniaxial compression tests were conducted on foliated phyllite with different foliation angles under dry and water-saturated conditions. The impacts of water content and foliation angle on the stress–strain curves and basic mechanical properties of the Phyllite were analyzed. The experimental results indicate that the peak stress and peak strain decrease first and then increase with increasing foliation angle as a U-shape or V-shape, and the phyllite specimens are weakened significantly by the presence of water. Moreover, an approach with acoustic emission, digital image correlation, and scanning electron microscopic is employed to observe and analyze the macroscopic and mesoscopic failure process. The results show that tensile microcracks dominate during the progressive failure of phyllite, and their initiation, propagation, and coalescence are the main reasons for the failure of the phyllite specimens. The water acts on biotite and clay minerals that are main components of phyllite, and it contributes to the initiation, propagation, and coalescence of numerous microcracks. Finally, four failure modes are classified as followed: (a) for the specimens with small foliation angles α = 0° or 30° (Saturated), both shear sliding and tensile-split across the foliation planes; (b) for the specimens with low to medium foliation angles α = 30° (Dry) or 45°(Saturated), shear sliding dominates the foliation planes; (c) for the specimens with medium to high foliation angles α = 45° (Dry) or 60°, shear sliding dominates the foliation planes; (d) for the specimens with high foliation angles α = 90°, tensile-split dominates the foliation planes.     

Constituent Parameter Identification of Braided Composite Based on Sensitivity Analysis

Mechanical properties of the constituent material of fiber-reinforced braided composites will inevitably change after the manufacturing process. An approach to constituent parameters’ identification of braided composites was proposed to obtain the basic information of composites for structural analysis. Identification of the constituent parameters was transformed as an optimization problem, which was solved by adopting the sensitivity analysis method, iteratively minimizing the discrepancies between the numerically calculated displacement field and the measured displacement field. The sensitivity matrix of displacements with respect to the constituent parameters was directly derived based on the constitutive material model for the first time. Considering that the large magnitude differences between parameters will lead to an ill-posed problem of the sensitivity matrix, the identification was susceptible to noise from the experimental data, the relative sensitivity was adopted, and a condition number-based response point selection was applied to improve the robustness of the parameter identification. A 2.5-dimensional braided composite was employed to illustrate the constituent parameter identification method by comparing with the finite difference method. In addition, the influence of selected measuring points and measuring errors on the proposed method were discussed. The results showed that the proposed method can be used to identify the constituent parameters efficiently and accurately. When the measured displacements are polluted by noise, the condition number of the sensitivity matrix is an effective indicator of preceding information to enhance the identification accuracy.     

Anatomically grounded estimation of hindlimb muscle sizes in Archosauria

In vertebrates, active movement is driven by muscle forces acting on bones, either directly or through tendinous insertions. There has been much debate over how muscle size and force are reflected by the muscular attachment areas (AAs). Here we investigate the relationship between the physiological cross‐sectional area (PCSA), a proxy for the force production of the muscle, and the AA of hindlimb muscles in Nile crocodiles and five bird species. The limbs were held in a fixed position whilst blunt dissection was carried out to isolate the individual muscles. AAs were digitised using a point digitiser, before the muscle was removed from the bone. Muscles were then further dissected and fibre architecture was measured, and PCSA calculated. The raw measures, as well as the ratio of PCSA to AA, were studied and compared for intra‐observer error as well as intra‐ and interspecies differences. We found large variations in the ratio between AAs and PCSA both within and across species, but muscle fascicle lengths are conserved within individual species, whether this was Nile crocodiles or tinamou. Whilst a discriminant analysis was able to separate crocodylian and avian muscle data, the ratios for AA to cross‐sectional area for all species and most muscles can be represented by a single equation. The remaining muscles have specific equations to represent their scaling, but equations often have a relatively high success at predicting the ratio of muscle AA to PCSA. We then digitised the muscle AAs of Coelophysis bauri, a dinosaur, to estimate the PCSAs and therefore maximal isometric muscle forces. The results are somewhat consistent with other methods for estimating force production, and suggest that, at least for some archosaurian muscles, that it is possible to use muscle AA to estimate muscle sizes. This method is complementary to other methods such as digital volumetric modelling.     

Size-Dependent Persistent Luminescence of YAGG:Cr3+ Nanophosphors

In the current work, YAGG:Cr³⁺ nanophosphors were synthesized by the Pechini method and then annealed at different temperatures in the range 800–1300 °C. The structure and morphology of the samples were characterized by X-ray Powder Diffraction (XRPD). The lattice parameters and average crystalline sizes as site occupation by Al³⁺ and Ga³⁺ ions were calculated from the Rietveld refinement data. To investigate the effect of crystalline size of the materials on their optical properties: excitation and emission spectra were recorded and analyzed. Finally, the effect of crystalline size on the probability of carrier recombination leading to PersL was determined experimentally with thermoluminescence analyses. The T_max-T_stop method was applied to determine the trap type and particle size (calcination temperature) effect on their redistribution. A correlation between structural changes and trap redistribution was found. In particular, the extinction of high-temperature TL maximum with increasing annealing temperatures is observed, while low-temperature TL maximum increases and reaches a maximum when the lattice parameter reaches saturation.     

Research on Hyperparameter Optimization of Concrete Slump Prediction Model Based on Response Surface Method

In this paper, eight variables of cement, blast furnace slag, fly ash, water, superplasticizer, coarse aggregate, fine aggregate and flow are used as network input and slump is used as network output to construct a back-propagation (BP) neural network. On this basis, the learning rate, momentum factor, number of hidden nodes and number of iterations are used as hyperparameters to construct 2-layer and 3-layer neural networks respectively. Finally, the response surface method (RSM) is used to optimize the parameters of the network model obtained previously. The results show that the network model with parameters obtained by the response surface method (RSM) has a better coefficient of determination for the test set than the model before optimization, and the optimized model has higher prediction accuracy. At the same time, the model is used to evaluate the influencing factors of each variable on slump. The results show that flow, water, coarse aggregate and fine aggregate are the four main influencing factors, and the maximum influencing factor of flow is 0.875. This also provides a new idea for quickly and effectively adjusting the parameters of the neural network model to improve the prediction accuracy of concrete slump.     

不同电针参数效应研究进展及思考

总结不同电针刺激参数：频率、波形、电针强度、刺激时间及其不同组合产生效应的研究进展,并对今后的电针参数效应研究进行展望。