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In order to solve the problems existing in traditional shaft sinking-hoists, the variable-frequency adjustable-speed system was designed for the sinking-hoists firstly. Then, taking four platform sinking-hoists as the research object, we studied strategy of synchronous controls of the sinking-hoists based on PID and model-reference adaptive control, simulated the performances of the synchronous strategy, and performed the field test. The results show that, after the reconstruction of controls parameters, the ability of anti-disturbance of the controls system have been enhanced and the motor speeds and sinking depths of the sinking-hoists have a great synchronous effect, greatly improved the predictability of the system.

Cosmic-ray data of 90 M events have been collected and used for calibration, alignment as well as detector tuning. A special tracking algorithm for the BESIII muon counter is developed and verified with Monte-Carlo simulation and then further confirmed with the cosmic-ray data. The obtained strip resolutions are in good agreement with the design values. A new alignment approach for the BESIII muon counter is confirmed with the cosmic-ray data and proposed to be used in future analysis of experimental data.

Purpose: To investigate the expression of tribbles homologue 3 (TRB3) and its regulation on endoplasmic reticulum stress (ERS)-induced photoreceptor apoptosis after retinal detachment (RD) using a rat model.Methods: RD animal model was created in Wistar rats by subretinal injection of 1% sodium hyaluronate. At various time points after RD, expression of TRB3 was detected by quantitative real-time PCR and Western blotting. TRB3 protein distribution in retina was evaluated by immunohistochemistry. RNA interference was used to inhibit TRB3 expression and subretinal injection of lentivirus TRB3 shRNA (LV-TRB3-sh) was performed. The rats were then randomly divided into four groups: normal control group, RD group, vehicle + RD group and LV-TRB3-sh + RD group. The mRNA and protein level of TRB3 as well as Caspase-12 were detected. TdT-mediated fluorescein-16-dUTP nick-end labeling (TUNEL) assay was used to detect the apoptosis of retinal cells. Retinal outer nuclear layer (ONL) thickness was measured to assess retina damage in each group.Results: TRB3 expression and TRB3-positive cell count were significantly increased after RD and peaked at day 3 after RD. The ratio of TUNEL-positive photoreceptors and expression of ERS-induced apoptosis marker Caspase-12 in LV-TRB3-sh + RD group were significantly reduced. The ONL thickness in LV-TRB3-sh + RD group was thicker than that both in RD group and vehicle + RD group.Conclusion: TRB3 expression is up-regulated in retinas after RD and knockdown of TRB3 protects photoreceptors against ERS-induced apoptosis. TRB3 may be a crucial molecule in photoreceptor apoptosis induced by ERS after RD.

The magnetic transition process in double-layer perovskite manganites is rather different from that in the counterpart compound with standard perovskite structure. In this paper, the magnetic phases below room temperature as well as the order of magnetic phase transition in terbium (Tb) doped La4/3Sr5/3Mn2O7 are studied by analyzing the magnetization curves, including thermal hysteresis, magnetic entropy change and its universal curve. The electrical conductivities with and without applied magnetic field are also discussed. Both the undoped and the doped samples (La1-xTbx)4/3Sr5/3Mn2O7 (x=0, 0.025) are prepared through the conventional solid-state reaction of mixed La2O3, Tb2O3, MnCO3 and SrCO3 whose purities are all higher than 99.9%. The mixture is calcined twice at 1000℃ for 12 h. Subsequently, the compactly compressed tablet of the calcined mixture is sintered in air at 1350℃ for 24 h. The data of X-ray diffraction show that the crystallographic structures of both samples are in the Sr3Ti2O7-type tetragonal phase with the space group I4/mmm. The refinement result indicates that the smaller radius of doped Tb3+ reduces all three lattice parameters as well as the c/a ratio, which is attributed to the preferential occupation of Tb3+ on the R site in rocksalt layer instead of the P site in perovskite layer. The temperature and field dependence of magnetization M(T, H), are recorded using the vibrating sample magnetometer of physical property measurement system (Quantum Design). Upon reducing the temperature, both samples exhibit two magnetic phase transitions from the paramagnetic phase at high temperature to the two-dimensional shortrange-ordered ferromagnetic state at the intermediate temperature, and finally the three-dimensional long-range-ordered antiferromagnetic state at low temperature. The zero-field-cooling and field-cooling curves display the characteristics of spin-glass behavior which may be due to the competition between B-site ferromagnetic and antiferromagnetic interactions associated with the randomly distributed A-site ions. The magnetic entropy changes of the samples are obtained through analyzing the magnetization data. The maximal magnetic entropy changes under 7 T magnetic field of the two samples are -4.60 J/(kgK) and -4.18 J/(kgK), respectively. The doped Tb ions reduce the transition temperatures, Tc2D and Tc3D, as well as the maximal value of magnetic entropy change, and increases the transition temperature range. The re-scaling curves of magnetic entropy change at different magnetic fields do not fall into a universal one, rather disperse in a wide interval, which suggests that the system undergoes a weak first-order transition at Tc3D. This conclusion is supported by the thermal hysteresis observed in the magnetization data. In addition, the electrical resistivity of the doped sample can be explained by using the small polaron model, which is different from three-dimensional variable-range hopping mechanism of undoped sample. On reducing temperature, the doped sample undergoes metal-insulator transition at temperature TP about 115 K, which is different from the undoped sample that shows the shoulder-shaped MI transition peaks. Under finite fields, the magnetoresistance value of intrinsic nature is about 56% near Tc3D.

The 2010 World Exposition in Shanghai China (Expo) was the largest mass gathering in world history, attracting a record 72 million visitors. More than 190 countries participated in the Expo, along with more than 50 international organizations. The 2010 Expo was six months in duration (May 1 through October 30, 2010), and the size of the venue site comprised 5.28 square kilometers. Great challenges were imposed on the public health system in Shanghai due to the high number and density of visitors, long duration of the event, and other risk factors such as high temperatures, typhoon, etc.As the major metropolitan public health agency in Shanghai, the Shanghai Municipal Center for Disease Control and Prevention (SCDC) implemented a series of actions in preparing for, and responding to, the potential health impact of the world's largest mass gathering to date, which included partnerships for capacity building, enhancement of internal organizational structure, risk assessment, strengthened surveillance, disaster planning and exercises, laboratory management, vaccination campaign, health education, health intervention, risk communication and mass media surveillance, and technical support for health inspection. The clear-cut organizational structures and job responsibilities, as well as comprehensive operational and scientific preparations, were key elements to ensure the success of the 2010 World Exposition.YiH, Zheng'anY, FanW, XiangG, ChenD, YongchaoH, XiaodongS, HaoP, MahanyM, KeimM. Public health preparedness for the world's largest mass gathering: 2010 World Exposition in Shanghai, China. Prehosp Disaster Med. 2012;27(6):1-6.

Based on the acoustic radiation theory of a dipole source, the influence of the transducer reception pattern is studied for magnetoacoustic tomography with magnetic induction (MAT-MI). Numerical studies are conducted to simulate acoustic pressures, waveforms, and reconstructed images with unidirectional, omnidirectional, and strong directional transducers. With the analyses of equivalent and projection sources, the influences of the model dimension and the layer effect are qualitatively analyzed to evaluate the performance of MAT-MI. Three-dimensional simulation studies show that the strong directional transducer with a large radius can reduce the influences of equivalent sources, projection sources, and the layer effect effectively, resulting in enhanced pressure and improved image contrast, which is beneficial for boundary pressure extraction in conductivity reconstruction. The reconstructed conductivity contrast images present the conductivity boundaries as stripes with different contrasts and polarities, representing the values and directions of the conductivity changes of the scanned layer. The favorable results provide solid evidence for transducer selection and suggest potential practical applications of MAT-MI in biomedical imaging.