The LIGO detection of gravitational waves(GW) from merging black holes in 2015 marked the beginning of a new era in observational astronomy. The detection of an electromagnetic signal from a GW source is the critical next step to explore in detail the physics involved. The Antarctic Survey Telescopes(AST3),located at Dome A, Antarctica, is uniquely situated for rapid response time-domain astronomy with its continuous night-time coverage during the austral winter. We report optical observations of the GW source(GW 170817) in the nearby galaxy NGC 4993 using AST3. The data show a rapidly fading transient at around 1 day after the GW trigger, with the i-band magnitude declining from 17:23 ± 0:13 magnitude to 17:72 ± 0:09 magnitude in ~1:8 h. The brightness and time evolution of the optical transient associated with GW 170817 are broadly consistent with the predictions of models involving merging binary neutron stars. We infer from our data that the merging process ejected about ~10^(-2) solar mass of radioactive material at a speed of up to 30% the speed of light.
Support Vector Machines(SVM) is a powerful machine learning method developed from statistical learning theory and is currently an active field in artificial intelligent technology. SVM is sensitive to noise vectors near hyperplane since it is determined only by few support vectors. In this paper, Multi SVM decision model(MSDM) was proposed. MSDM consists of multiple SVMs and makes decision by synthetic information based on multi SVMs. MSDM is applied to heart disease diagnoses based on UCI benchmark data set. MSDM somewhat inproves the robust of decision system.
Influenza virus contains three integral membrane proteins:haemagglutinin,neuraminidase,and matrix protein(M1 and M2).Among them,M2 protein functions as an ion channel,important for virus uncoating in endosomes of virus-infected cells and essential for virus replication.In an effort to explore potential new functions of M2 in the virus life cycle,we used yeast two-hybrid system to search for M2-associated cellular proteins.One of the positive clones was identified as human Hsp40/Hdj1,a DnaJ/Hsp40 family protein.Here,we report that both BM2(M2 of influenza B virus)and A/M2(M2 of influenza A virus)interacted with Hsp40 in vitro and in vivo.The region of M2-Hsp40 interaction has been mapped to the CTD1 domain of Hsp40.Hsp40 has been reported to be a regulator of PKR signaling pathway by interacting with p58^(IPK) that is a cellular inhibitor of PKR.PKR is a crucial component of the host defense response against virus infection.We therefore attempted to understand the relationship among M2,Hsp40 and p58^(IPK) by further experimentation.The results demonstrated that both A/M2 and BM2 are able to bind to p58^(IPK)in vitro and in vivo and enhance PKR autophosphorylation probably via forming a stable complex with Hsp40 and P58^(IPK),and consequently induce cell death.These results suggest that influenza virus M2 protein is involved in p58^(IPK)mediated PKR regulation during influenza virus infection,therefore affecting infected-cell life cycle and virus replication.
Zhenhong GuanDi LiuShuofu MiJie ZhangQinong YeMing WangGeorge F.GaoJinghua Yan
Residual stress measurement is of critical significance to in-service security and the reliability of engineering components, and has been an active area of scientific interest. This paper offers a review o[ several prominent mechanical release methods for residual stress measurement and recent developments, focusing on the hole-drilling method combined with advanced optical sensing. Some promising trends for mechanical release methods are also analyzed.
In the industrial process situation, principal component analysis (PCA) is ageneral method in data reconciliation. However, PCA sometime is unfeasible to nonlinear featureanalysis and limited in application to nonlinear industrial process. Kernel PCA (KPCA) is extensionof PCA and can be used for nonlinear feature analysis. A nonlinear data reconciliation method basedon KPCA is proposed. The basic idea of this method is that firstly original data are mapped to highdimensional feature space by nonlinear function, and PCA is implemented in the feature space. Thennonlinear feature analysis is implemented and data are reconstructed by using the kernel. The datareconciliation method based on KPCA is applied to ternary distillation column. Simulation resultsshow that this method can filter the noise in measurements of nonlinear process and reconciliateddata can represent the true information of nonlinear process.
Yan Weiwu Shao HuiheDepartment of Automation,Shanghai Jiaotong University,Shanghai 200030, China
BACKGROUND Acupuncture promotes the recovery of gastrointestinal function and provides analgesia after major abdominal surgery.The effects of transcutaneous electrical acupoint stimulation(TEAS)remain unclear.AIM To explore the potential effects of TEAS on the recovery of gastrointestinal function after gastrectomy and colorectal resection.METHODS Patients scheduled for gastrectomy or colorectal resection were randomized at a 2:3:3:2 ratio to receive:(1)TEAS at maximum tolerable current for 30 min immediately prior to anesthesia induction and for the entire duration of surgery,plus two 30-min daily sessions for 3 consecutive days after surgery(perioperative TEAS group);(2)Preoperative and intraoperative TEAS only;(3)Preoperative and postoperative TEAS only;or(4)Sham stimulation.The primary outcome was the time from the end of surgery to the first bowel sound.RESULTS In total,441 patients were randomized;405 patients(58.4±10.2 years of age;247 males)received the planned surgery.The time to the first bowel sounds did not differ among the four groups(P=0.90;log-rank test).On postoperative day 1,the rest pain scores differed significantly among the four groups(P=0.04;Kruskal–Wallis test).Post hoc comparison using the Bonferroni test showed lower pain scores in the perioperative TEAS group(1.4±1.2)than in the sham sti-mulation group(1.7±1.1;P=0.04).Surgical complications did not differ among the four groups.CONCLUSION TEAS provided analgesic effects in adult patients undergoing major abdominal surgery,and it can be added to clinical practice as a means of accelerating postoperative rehabilitation of these patients.