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目的 分析影响初治多发性骨髓瘤（NDMM）患者早期死亡（EM）的因素，建立其预测模型，以期识别EM风险。 方法 回顾性分析2009年5月至2017年1月吉林大学白求恩第一医院收治的275例NDMM患者，对6个月（EM6）、12个月（EM12）及24个月（EM24）内死亡患者初诊时基线特征进行单因素分析，并根据多因素分析结果建立EM的预测模型。 结果 本研究中EM6、EM12及EM24的发生率分别是5.5%、12.7%和30.2%；最常见的死亡原因为疾病复发/进展，在EM6、EM12及EM24中分别占60.0%、77.1%及84.3%。影响EM6的因素包括经白蛋白校正的血清钙（校正钙）>2.75 mmol/L和PLT75岁、国际分期系统（ISS） Ⅲ期、修订版国际分期系统（R-ISS） Ⅲ期、校正钙>2.75 mmol/L、血清肌酐>177 µmol/L、PLT75岁、PLT75岁：1分；PLT75岁、PLT

We present a new method of DEEM, the direct energy encircling method, for characterising the performance of fibres in most astronomical spectroscopic applications. It's a versatile platform to measure focal ratio degradation (FRD), throughput, and point spread function (PSF). The principle of DEEM and the relation between the encircled energy (EE) and the spot size were derived and simulated based on the power distribution model (PDM). We analysed the errors of DEEM and pointed out the major error source for better understanding and optimisation. The validation of DEEM has been confirmed by comparing the results with conventional method which shows that DEEM has good robustness with high accuracy in both stable and complex experiment environments. Applications on the integral field unit (IFU) show that the FRD of 50$\mu$m core fibre is substandard for the requirement which requires the output focal ratio to be slower than 4.5. The homogeneity of throughput is acceptable and higher than 85 per cent. The prototype IFU of the first generation helps to find out the imperfections to optimise the new design of the next generation based on the staggered structure with 35$\mu$m core fibres of $N.A.$=0.12, which can improve the FRD performance. The FRD dependence on wavelength and core size is revealed that higher output focal ratio occurs at shorter wavelengths for large core fibres, which is in agreement with the prediction of PDM. But the dependence of the observed data is weaker than the prediction., Comment: 39 pages, 49 figures, accepted for publication in MNRAS in Feb. 2018

Focal ratio degradation (FRD) is a major contributor to throughput and light loss in a fibre spectroscopic telescope system. We combine the guided mode theory in geometric optics and a well-known model, power distribution model (PDM), to predict and explain the FRD dependence properties. We present a robust method by modifying the energy distribution method (EDM) with \emph{f-intercept} to control the input condition. This method provides a way to determine the proper position of the fibre end on the focal plane to improve energy utilization and FRD performance, which lifts the relative throughput up to 95\% with variation of output focal ratio less than 2\%. And this method can also help to optimize the arrangement of the position of focal-plane plate to enhance the coupling efficiency in a telescope. To investigate length properties, we modified PDM by introducing a new parameter, focal distance \emph{f}, into the original model to make it available for multi-position measurement system. The results show that the modified model is robust and feasible for measuring the key parameter \emph{d}$_0$ to simulate the transmission characteristics. The output focal ratio in the experiment does not follow the prediction trend but shows an interesting phenomenon that the output focal ratio increases at first to the peak, then decreases and remains stable finally with increasing fibre length longer than 15m, which provides a reference for choosing appropriate length of fibre to improve the FRD performance for the design of the fibre system in a telescope.

阻塞性睡眠呼吸暂停低通气综合征（OSAHS）存在睡眠期间歇性低氧和睡眠片段化，可导致日间嗜睡和心脑血管损伤等不良事件，已越来越受到人们的重视。目前OSAHS的一线治疗方法为持续气道正压通气，疗效较好，但患者依从性差，尚缺乏有效的药物治疗。近年来，关于OSAHS发病机制的4个病理生理要素逐渐受到关注：代表上气道结构因素的临界闭合压（Pcrit，P）异常、低觉醒阈值（arousal threshold，A）、代表呼吸控制不稳定性的高环路增益（loop gain，L）以及上气道扩张肌功能异常（dilator muscle dysfunction，M），统称为PALM模型。本文立足PALM模型，综述相关治疗药物的研究进展。.

The effect of cement/sand ratio of the original mortar, type of the activators and addition of slag powder on alkali activated recycled cement mortar powder (AARCMP) pastes were studied. The results show that the cement hydrates in recycled cement mortar can be activated by alkali to reconstruct new cementitious substances. Water glass is more effective as an activator than NaOH. Recycled cement mortar with higher original cement/sand ratio yields higher strengths, and addition of slag powder can remarkably increase the strengths of the materials. AARCMP paste with the 28 day flexural and compressive strengths of 7·5 and 45·4 MPa respectively was prepared by replacing 30% slag powder for the recycled mortar powder. Scanning electron microscopy revealed that there is a great difference between the microstructures of the hardened paste of AARCMP and that of ordinary Portland cement.

The effects of curing temperature on alkali activated slag cement (AAS) were investigated. The results indicate that the impact of the curing temperature is much more significant on the setting time of AAS than that of ordinary Portland cement. Curing at below normal temperature (∼7°C) greatly prolongs both the initial and final setting times, and also remarkably reduces the early age strength of AAS, whereas it will not lead to significant reduction in late age strengths. Scanning electron microscopy revealed significant difference in microstructures of AAS pastes cured for 28 days, and the compactness of the paste structure increases greatly with the increasing of the curing temperature.

We present a multiple time windows beamformer (MTWB) method of solving the inverse problem of magnetic field and non-invasively imaging the cardiac electrical excitation conduction using the magnetocardiac signals acquired by a 61-channel superconducting quantum interference device (SQUID). The MTWB constructs spatial filters for each location in source space, one for each component of the source moment based on the distributed source model, and estimates the cardiac equivalent current sources. The output of spatial filters is the source strength estimated in three-dimensional space and the weight matrix calculated with magnetocardiac signals in multiple time windows. A signal subspace projection technique is used to suppress noise. Then, the characteristics of cardiac electrical excitation conduction among two healthy subjects and two coronary vessel stenosis (CVS) patients are extracted from reconstructed current sources with maximum strength at each instant during QRS complex and ST-T segment, and a series of two-dimensional cardiac electrical excitation conduction maps (EECM) are obtained. It is demonstrated that two healthy subjects are of similar and the stronger electrical activities than those of two CVS patients. This technique can be used as an effective tool for the diagnosis of heart diseases.

The polynomial-fit method is applied to remove the uneven background of a satellite when it is near a bright primary object. Detailed analysis of this method is given. Some useful conclusions are drawn from the results of simulated data.

This paper reports on our observing campaign of faint satellites performed at the National Time Service Center and Sheshan station of SHAO from 1994 up to today. In the past few years due to benefit from using a large size CCD and the publication of the modern catalogues (UCAC2), a series of observations of faint satellites were obtained by us. Moreover the work of improving the orbit of Phoebe via numerical fit to the observations over a century is also presented.

Astrometric positions of the Neptunian Satellite Triton are given for the opposition of Neptune for the years 1996, 2003, 2005 and 2006. The 943 observed positions were obtained at the Cassegrain focus of a 156-cm reflector. In our reduction, the up-to-date catalogue of stars UCAC2 was chosen to ensure a proper astrometric calibration. Our observed positions are compared to theoretical positions provided from JPL and IMCCE ephemerides. The observed minus calculated residuals have s.d. values of the order of 0.04 arcsec.

In 2003-2004, we obtained 115 new observations of Phoebe, the 9th Saturnian faint satellite (visual magnitude of about 16.5). We used a large CCD detector (2048 x 2048 pixels) mounted on the 1.56 m astrometric reflector at the Sheshan Station, near Shanghai. In our reduction, an up-to-date catalogue of stars, UCAC2 (Zacharias et al. 2004), was chosen to ensure a proper astrometric calibration. A comparison of our observations to three recently available, high quality ephemerides, including the JPL SAT185 by Jacobson (2004b), has shown that most of our observed positions of Phoebe present an accuracy of some tens of mas, which appears to be a very high level for such a faint satellite.