目的:探讨影响205例长期维持性腹膜透析(PD)患者生存预后的因素.方法:回顾性分析205例长期维持性PD患者的病例资料,依据其预后进行分组,其中预后良好为预后良好组(n=148),预后不良的患者分为预后不良组(n=57),分析影响患者生存预后的危险因素.结果:年龄(≥70岁)、透析时间、GLU、CCI(≥5)、透析充分性(GFR、总Kt/V、残余肾Kt/V)、Hb、Alb、HDL、hs-CPR均是影响长期维持性PD患者生存预后的单因素;年龄(≥70岁)、透析时间、GLU、透析充分性、Hb、Alb及hs-CPR均是影响长期维持性PD患者生存预后的独立危险因素.结论:长期维持性PD患者生存预后不良的独立危险因素为年龄、原发病、透析时间、GLU、透析充分性、Hb、Alb及hs-CPR,临床需进行针对性、有效干预来提高患者的生存率.

工科对于动手能力培养的课程主要集中在实验课程。在新工科教学改革的大环境下，如何最大程度地发挥实验课程的作用？如何以学生为中心，发挥学生学习的主观能动性等问题是亟待工科实验授课教师解决的问题。本文介绍了对大学一年级专业选修课程《电工电子测量技术与实验》课程进行的教改，在不减少验证性实验的基础上增加了设计性实验内容；改变了评分标准，提升了学生自主学习的积极性；开放设计题目，将学生的想象力和创新思维能力融入到课程设计中。为新工科思维下，实验教学改革做了一定的探索。

混合式教学方式促进了传统的课堂教学形式和现代化的网络教学的结合，疫情下，基于SPOC和直播授课的“电工技术基础”课程的混合式教学改革值得探索。在公共基础课“电工技术基础”教学实践中，通过SPOC和直播课程结合，实施以知识体系化构建为基础，以理论与实际结合为目标，具有多维互动的教学过程、多元化的教学资源、多样化的考核方式的特点的课程教学改革实践，发挥了学生主观能动性，提高了学生的参与意识，达到了较好的教学效果。

In the present work, a chemical reaction has been performed for supramolecular gels to achieve multiple-stimuli-responsive smart soft materials. Simple chiral binaphthalene-based receptors can condense with histidine (His) to yield a Schiff base, which would help to achieve visual chiral recognition of unprotected L/D-His through gel formation along with specific selectivity toward 20 amino acids. Through intermolecular hydrogen bonds, the resultant Schiff base molecules assemble with excess His molecules to form three-dimensional (3D) networks of metastable cross-linked nanospheres and stable nanofibers in EtOH/water and MeOH/water, respectively. Significantly, this condensation reaction exhibits unique reversible and chromatic phenomena between sol-gel phase transitions in EtOH/water, which provide a way to design chemical reaction-based multivisual-change supramolecular gels for sensing and switching applications.

Solid-state photochromic switches with reversible luminescence modulation property have wide applications in optical data storage, anticounterfeiting, sensing, and bioimaging, however, it is a significant challenge to design and prepare such materials. In the present work, a novel class of chiral and helical binaphthyl-substituted spiropyrans has been synthesized and characterized. The introduction of binaphthyl can not only promote the solid-state luminescence but also achieve the interesting chiroptical switching properties for the potential applications in chiral recognition and circularly polarized luminescence. The single-crystal structures and density functional theory calculations reveal that the presence of strong electron-withdrawing nitro groups can promote photoswitch efficiency by stabilizing the electron-rich conjugated merocyanine with the lower electron cloud density and LUMO/HOMO levels. For charge transfer in excited states, π → π* transition would enhance emission, but n → π* transition and intramolecular charge transfer show the opposite effect. Therefore, these photochromic switches provide a novel paradigm in the design of multiple-responsive, chiral, and luminescent materials.

A series of binuclear cyclometalated Pt(ii) complexes with the bridge ligand of binaphthyl quinoline were synthesized and characterized. Owing to the restriction of intramolecular motions in chiral binaphthyl linkers, the complexes exhibited two unusual metal-induced chiral components and aggregation-induced red phosphorescence. The (R,R,R)/(S,S,S) enantiopure complexes that were confirmed by X-ray diffraction, circular dichroism spectra, time-dependent density functional theory calculations, and circularly polarized luminescence did not require purification by chiral high-performance liquid chromatography and could yield unique 1D M or P hierarchical helices of helices via intermolecular noncovalent interactions. Moreover, it is the first time that racemization-induced phosphorescence enhancement has been observed.

Objective To analyze the pathogenic bacteria distribution and drug resistance in patients with chronic obstructive pulmonary disease(COPD) and lower respiratory tract infections and provide references for the clinical diagnosis and treatment.Methods The sensitivity and drug resistance of pathogenic bacteria were analyzed and summarized by reviewing the analysis results of 1,237 strains of pathogenic bacteria isolated from the sputum samples of the COPD patients with lower respiratory tract infections treated in West China Hospital of Sichuan University from November of 2014 to October of 2016 and 1,453 strains of pathogenic bacteria isolated from the sputum samples of the non-COPD patients with lower respiratory tract infections at the corresponding period.Results Among the 1,237 strains of pathogenic bacteria isolated from the patients with COPD and lower respiratory tract infections, 80.7% of them are gram-negative bacteria, 15.4% are gram-positive bacteria and 3.9% are fungi.The common bacteria in the gram-negative bacteria were pseudomonas aeruginosa, klebsiellar pneumoniae, acinetobacter baumannii, stenotrophomonas maltophilia and escherichia coli, which accounted for 25.6%, 20.0%, 17.0%, 6.2% and 5.5% respectively.The common bacteria in gram-positive bacteria were Staphylococcus aureus and Streptococcus pneumoniae, which accounted for 7.7% and 6.2% respectively.Candida albicans is the most common in fungi.Gram-negative bacteria showed moderate susceptibility to Amikacin,Cefepime, Imipenem, Ceftazidime, Piperacillin/Tazobactam and Levofloxacin, and they showed high frequency of drug resistance to Ampicillin, Ampicillin/Sulbactam, Cefazolin, Cefotetan, Trimethoprime/Sulfamethxazole and Ceftriaxone.The staphylococcus aureus in Gram-positive bacteria showed high susceptibility to Linezolid, Tigecycline, Vancomycin, levofloxacin, rifampicin, moxifloxacin, Oxacillin, and Quinupristin/Dalfopristin, and they showed high frequency of drug resistance to chlorine lincomycin, Erythromycin and penicillin G.Streptococcus pneumoniae showed high susceptibility to amoxicillin, Ertapenem, levofloxacin, ofloxacin, penicillin(other), telithromycin, vancomycin, chloramphenicol, Linezolid, and moxifloxacin, and they showed high frequency of drug resistance to erythromycin, penicillin(oral) and Tetracycline.Conclusion The Gram-negative bacteria are the main pathogens in the sputum samples isolated from the patients with COPD and lower respiratory infections, and the pathogenic bacteria distribution of those patients is different from that of the non-COPD patients with lower respiratory infections.The pathogenic bacteria has high rate of drug resistance to antibiotics, so antibiotics should be selected more rationally by identifying the pathogens clearly in the process of treatment.

Objective To analyze the bloodstream infections caused by vancomycin‐resistant Enterococcus (VRE)in West China Hospital and examine the risk factors of such infections for best control of VRE infections .Methods Case‐control method was used to compare the bloodstream infections due to VRE with those caused by vancomycin‐susceptible Enterococcus(VSE)from August 2010 to August 2014 in West China Hospital .The data were compared by T‐test ,Chi‐square test (univariate analysis) and logistic regression analysis (multivariate analysis) using SPSS 19 .0 software .Results A total of 31 VRE strains were isolated from bloodstream infections in the study period ,including 5 (16 .1 % ) strains of vancomycin‐resistant Enterococcus faecalis and 26 (83 .9 % )strains of vancomycin‐resistant Enterococcus faecium .In the past four years ,the prevalence of vancomycin‐resistant E . f aecalis in bloodstream infections was 1 .5% ,1 .6% ,1 .8% ,and 1 .2% ;while the prevalence of vancomycin‐resistant E . f aecium in bloodstream infections was 3 .8% ,4 .4% ,5 .8% ,and 7 .1% .Such VRE bloodstream infection was mainly found in Intensive Care Unit (ICU)(13 ,41 .9% )and Department of Neurosurgery (4 ,12 .9% ) .More than 90% of the isolates were resistant to ampicillin and erythromycin .But less than 20% of the strains were resistant to quinupristin‐dalfopristin and linezolid . Univariate analysis indicated that prolonged hospital stay , ICU admission , venous catheter ,prior carbapenem exposure , prior vancomycin/norvancomycin exposure were associated with VRE bloodstream infections .Logistic regression analysis confirmed that venous catheter was an independent risk factor of VRE bloodstream infections .Conclusions Venous catheter is an independent risk factor for VRE bloodstream infections . Infection control measures should be strengthened to prevent the outbreak of VRE‐related bloodstream infections .

The sliding mode variable structure control for spherical 2-DOF robots was proposed on the basis of kinematical and dynamical models.The mechanism and dynamic model for spherical 2-DOF robot were described.The exponential reaching law for determining additional compensation torque was introduced,and then the control algorithm of spherical 2-DOF robots was established.The influence of applied force,mass,moment of inertia and control parameters on the control accuracy and stability of spherical 2-DOF robots was studied.The example of simulation control for spherical 2-DOF robots was undertaken and the result showed that the method is effective.The oscillation of system can be avoided,and then stability and good robustness of system can be kept and the high accuracy of system can be obtained by choosing appropriate parameters.

Analytical dynamic model for planar adjustable seven-bar mechanisms is established based on kinematic analysis,Kane dynamic equation,numeric-symbolic approach and parallel calculation.The influence of lengths and inertia parameters of links on driving force/torque are also studied.The closed vector approach is applied in the kinematical analysis of planar adjustable seven-bar mechanisms and expressions of velocity and acceleration of links are obtained.Then the numeric-symbolic expressions of the analytical dynamic model are derived in which lengths and inertia parameters of links as well as generalized coordinates are expressed as symbols,the other variables as numeral,and a parallel algorithm is also proposed.The procedures of dynamic modeling and real-time code optimization can be performed off-line and parallel calculation structure is adopted,therefore on-line calculation time can be reduced greatly,which is of advantage to real-time control of mechanisms.The examples of dynamic simulation showed that the method is effective.

针对虚拟轴机床位置精度高、钢度大、机械结构简单等特点,提出了基于BP神经网络的实时误差补偿控制策略.应用BP神经网络对虚拟轴机床的运动学反解进行学习,利用训练好的神经网络对虚拟轴机床进行误差补偿;给出三坐标虚拟轴机床误差补偿的仿真结果.表明这种补偿控制方案十分有效,补偿后能较大地减小机床的位置误差.