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To investigate the changes of brain CT imaging in patients with cerebral cysticercosis during the period of anti-cysticercus chemotherapy.A total of 380 inpatients that were conformed to the practical diagnostic criteria of cerebral cysticercosis were enrolled in this study in the Third Affiliated Hospital of Shandong Academy of Medical Sciences from May 2010 to May 2015. All the patients were given anti-cysticercus chemotherapy (albendazole and praziquantel). All the patients received brain CT scan, and of which 210 received enhanced scan. The data of CT imaging were systematically reviewed.Before the treatment, the CT images of the patients showed single or multiple small cystic (s) with low density and small nodule-like cephalomere with high density. The re-examinations of CT showed that there were 81.58% (310/380) of the patients whose low density foci were completely absorbed, there were 16.32% (62/380) of the patients whose foci were mostly absorbed, and there were 2.11% (8/380) of the patients whose foci were calcified. Along with the prolongation of treatment time, the side effects were gradually reduced, and in the third course of treatment, the foci were absorbed or calcified in most of the patients.CT examination can diagnose the lesion site, range and classification of cerebral cysticercosis, and can evaluate the effect of the therapy according to the changes of CT imaging during the period of anti-cysticercus chemotherapy.[

Atomic clocks provide the most accurate definition for time. The precision of atomic clock has been improved by many orders of magnitude since the first atomic clock was built. However, the interatomic interaction usually suppress the precision of atomic clock. As a result, it is especially meaningful to study the interaction effect in atomic clock, which is considered to be helpful in improving the precision and accuracy of atomic clock. In order to characterize the collision effect induced clock shift, we theoretically study the collision clock shift in the Rabi spectrum, caused by the short-range interaction between two Fermi atoms in harmonic potential. Given that the short-range interatomic interaction is generally weak, and that the parameters of external lattice laser field are in the Lamb-Dicke regime, we make an approximation that the spatial wave-function of the Fermi atoms does not change, and then derive the motion equation for the internal wave-function under the external Rabi driving field. We solve the equation of motion by the perturbative method, and obtain the solution to first order, and thus derive the expression of the collision clock shift of the Rabi spectrum in terms of the interatomic interaction and the external Rabi driving laser field parameters for specific spatial wave-functions of atoms. Finally, we use the exact expression of the Green’s function in harmonic potential to obtain the averaged clock shift of collision at finite temperatures. Our results relate the atomic interaction with atomic clock shift, and provide a unified description of all partial waves of atomic interaction induced clock shift. Therefore, it becomes much more convenient to study the contributions of different partial waves to atomic clock shift. On the other hand, our results indicate that through precisely measuring the clock shift, the information about the interatomic interactions can also be obtained. In addition, our results for two interacting atoms can inspire the future study of real many-body interacting system which will be the next research topic.

Output characteristics of Yb-doped double-cladding pulsed fiber amplifiers were discussed under conditions of low and high repetition rates using the time-dependent rate equations.Because there are several different initial conditions used in the finite-difference method with different repetition rates,some methods were presented to determine the initial conditions.The relationship of the peak powers of the high repetition rates with their equivalent continuous wave powers was also discussed when the signal light was in Gaussian shape.The change of the average output power with the pump power was obtained under the conditions of the pulsed signals with low repetition rates and high repetition rates.

We demonstrate a high-repetition-rate Er-doped all fiber laser with nonlinear-polarization-rotation mode-locking. The highest repetition rate of the laser is 217 MHz. The fiber laser has a very simple and compact structure and can output a stable mode-locking pulse only by using one polarization-dependent isolator and a polarization controller. The pulse width, spectral width and signal-to-noise ratio are measured to be 69 fs, 56 nm and 76 dB respectively.

We demonstrate the first use of single layer graphene for compressing self-Q-switching pulses in semiconductor disk lasers. The gain region of the semiconductor disk laser used InGaAs quantum wells with a central wavelength of 1030 nm. Due to self saturable absorption of the quantum wells, the disk laser emitted at the self-Q-switching state with a pulse width of 13 μs. By introducing the single layer graphene as a saturable absorber into the V-shaped laser cavity, the pulse width of the self-pulse was compressed to 2 μs with a lower pump power of 300 mW. As the pump power was increased, multiple pulses with the pulse width of 1.8 μs appeared. The compression factor was about 7.2.

We present a novel architecture description language - OPNADL. The domain specific software architecture based on OPNADL is employed to guide the large-scale software development. OPNADL (object-oriented Petri nets architecture description language) is a graphical and mathematical modeling language, which can be used to describe static and dynamic semantics, and analyze the dynamic behavior of software system. The overall and individual characteristics of a system can be visually and intuitively depicted with the proposed OPNADL. Software architecture is conveniently constructed, refined and verified by OPNADL.

A saturable absorber of 3.9% modulation depth was prepared on the surface of a fiber clad with single-walled carbon nanotubes (SWCNT) using chemical corrosion method. An all-fiber Er-doped fiber laser was setup with a ring cavity, and was mode-locked successfully by evanescent field mode-locking using prepared saturable absorber of single-walled carbon nanotubes. A 147 fs mode-locking pulse is obtained near 1556 nm with a 3 dB bandwidth of 24 nm. The output power is 21 mW at a pump power of 520 mW, corresponding to a pulse energy of 0.14 nJ with a repetition rate of 150 MHz.

Support vector regression (SVR) is an effective method for the predication of chaotic time-series, which is a fundamental topic of nonlinear dynamics. Through analyzing the possible variation of support vector sets after new samples are inserted to the training set, a novel SVR algorithm is proposed; thus an online learning algorithm is set up. In connection with the specific characteristics of chaotic signals, a wavelet kernel satisfying wavelet frames is also presented. The wavelet kernel can approximate arbitrary functions, and is especially suitable for local processing; hence the generalization ability of SVR is improved. To illustrate the good performance of the online wavelet SVR, a benchmark problem, i.e. the online prediction of chaotic Mackey-Glass time-series, is considered. The simulation results indicate that the online wavelet SVR algorithm outperforms the existing algorithms in higher efficiency of learning as well as better accuracy of prediction.