SCOPE: Scalable Composite Optimization for Learning on Spark

Many machine learning models, such as logistic regression~(LR) and support vector machine~(SVM), can be formulated as composite optimization problems. Recently, many distributed stochastic optimization~(DSO) methods have been proposed to solve the large-scale composite optimization problems, which have shown better performance than traditional batch methods. However, most of these DSO methods are not scalable enough. In this paper, we propose a novel DSO method, called \underline{s}calable \underline{c}omposite \underline{op}timization for l\underline{e}arning~({SCOPE}), and implement it on the fault-tolerant distributed platform \mbox{Spark}. SCOPE is both computation-efficient and communication-efficient. Theoretical analysis shows that SCOPE is convergent with linear convergence rate when the objective function is convex. Furthermore, empirical results on real datasets show that SCOPE can outperform other state-of-the-art distributed learning methods on Spark, including both batch learning methods and DSO methods

Optically-Nonactive Assorted Helices Array with Interchangeable Magnetic/Electric Resonance

We report here the designing of optically-nonactive metamaterial by assembling metallic helices with different chirality. With linearly polarized incident light, pure electric or magnetic resonance can be selectively realized, which leads to negative permittivity or negative permeability accordingly. Further, we show that pure electric or magnetic resonance can be interchanged at the same frequency band by merely changing the polarization of incident light for 90 degrees. This design demonstrates a unique approach to construct metamaterial.Comment: 15 pages, 4 figure

Awake anesthesia for resection of gliomas located in eloquent brain

Intraoperative awake anesthesia is a safe and reliable method performed in glioma surgery in brain eloquent areas, for the purpose of a maximum resection of the lesions and protection of brain function. Plasma target⁃controlled infusion (TCI) is used in the course of opening cranium and closing cranium to maintain optimal sedation, which is supplemented by excellent scalp nerve block for analgesia, and a laryngeal mask is used to secure the patient's airway. During cerebral function monitoring and lesion excision, appropriately modifying the plasma concentration of propofol TCI can make the patient achieve optimal sedation. DOI：10.3969/j.issn.1672⁃6731.2012.06.00

Anticoagulant effect of low molecular weight heparin on central venous catheters in haemodialysis patients

Purpose: To analyse the effect of low molecular weight heparin on venous catheters in haemodialysis patients.Methods: This study included 140 eligible patients who were randomly and evenly divided into two groups, viz, a study group that received low molecular weight heparin and a control group that received conventional heparin. The clinical effects and incidence of complications were compared for the two groups.Results: No significant difference in general characteristics or the incidence of tube occlusion was detected between the two groups. The mean blood flow volume of the study and control groups were 223.50 ± 19.10 and 222.70 ± 18.70 mL/min, respectively (t = 0.940, p > 0.05), and the incidences of complications (long-term vascular secondary changes and bleeding tendency within 1 year after tube in dwelling) were lower in the study group than in the control group. After haemodialysis, the activated partial thromboplastin time and prothrombin time were shortened in the study group compared with the control group, whereas the platelet level was higher in the study group (146 ± 33 × 109/L) than in the control group (95 ± 36 × 109/L).Conclusion: The use of low molecular weight heparin as an anticoagulant solution for patients undergoing haemodialysis with central venous catheters (CVCs) is less likely to induce haemodialysisassociated complications and has fewer effects on coagulation function than conventional heparin. Thus, low molecular weight heparin seems to be more suitable as an anticoagulant solution in patients with venous catheters.Keywords: Low molecular weight heparin, Haemodialysis, Central venous catheter, Vascular acces