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AIM: To detect an earlier improvement in mild to moderate keratoconus following corneal cross-linking (CXL) with total corneal refractive power (TCRP) using ray tracing method. METHODS: A total of 40 eyes of 30 consecutive patients who underwent CXL for progressive keratoconus were retrospectively enrolled. The following keratometric parameters provided by Pentacam HR, including maximum keratometry (Kmax), steepest keratometry (Ksteep), 3 mm zonal TCRP centered over corneal apex (TCRP(apex,zone) 3 mm), zonal mean keratometry and TCRP centered over corneal cone (Km(cone,zone) and TCRP(cone,zone) 1, 2, 3 mm) were evaluated preoperatively and 1, 3, 6, and 12mo postoperatively. Groups 1 and 2 were defined based on Kmax at postoperative 1mo as improved (the initial improvement group) or worsen (the initial deterioration group) compared to the preoperative level. RESULTS: In the overall group, only keratometric parameters based on ray tracing method displayed significant improvement early at 3mo postoperatively, in which TCRP(cone,zone) 1 mm and 2 mm exhibited the largest flattening (0.57 D and 0.53 D, respectively). In Group 1, only Kmax, Km(cone,zone) 2 mm and TCRP(cone,zone) 2 mm showed significant improvement initially at 1mo postoperatively, in which Kmax exhibited the largest improvement (1.05 D), followed by TCRP(cone,zone) 2 mm (0.82 D). In Group 2, only keratometric parameters based on ray tracing method and Km(cone,zone) 3 mm showed slight but not significant improvement early at 3mo, in which TCRP(cone,zone) 3 mm displayed the most improvement (0.19 D), followed by TCRP(cone,zone) 2 mm (0.15 D). CONCLUSION: The findings indicate that a 2 mm zonal TCRP centered over Kmax could earlier detect keratometric improvement by CXL compared to other commonly used parameters in mild to moderate keratoconic eyes.

With the rapid development of the E-commerce, the text of the products?? advertisement and recommendation is extremely vital in the case that people cannot touch the real products. Traditional product descriptions which are written manually show the same product information to all users, which do not consider that different users pay attention to different attributes. Moreover, the efficiency of manually written product descriptions cannot match the growth rate of products, so how to automatically generate personalized product descriptions has become a frontier research problem. This paper mainly studies the generation of personalized product description, takes the personalized characteristics of users into account and generates the product description text corresponding to the interest for each user. Due to the lack of personalized product description data set, the CrowdDepict model is proposed. It collects relevant corpus through public data sources such as Douban and JD, and generates personalized product description with product comments, etc. The experimental results show that the personalized product description model CrowdDepict can automatically generate the personalized product description according to the user preference, the description covers the user interest and product characteristics, and the text expression is smooth.

Wei Liu,1 Li-Na Liu,1 Cai-Wei Lin,1 Hao-Yu Wang,2 Xu-Dong Wang1 1Department of Emergency, Aerospace Center Hospital (Peking University Aerospace School of Clinical Medicine), Beijing, 100049, People’s Republic of China; 2Department of Radiology, Aerospace Center Hospital (Peking University Aerospace School of Clinical Medicine), Beijing, 100049, People’s Republic of ChinaCorrespondence: Xu-Dong WangDepartment of Emergency, Aerospace Center Hospital (Peking University Aerospace School of Clinical Medicine), No. 15 of Yuquan Street, Haidian District, Beijing, 100049, People’s Republic of ChinaTel +86 10 59971968Fax +86 10 59971199Email xudongwang59@163.comAbstract: We present the case of a 60-year-old woman who suddenly suffered a witnessed cardiac arrest and did not achieve return of spontaneous circulation despite being given 150-minute ultra-long cardiopulmonary resuscitation (CPR). During CPR, pulmonary embolism was suspected and was eventually diagnosed based on refractory pulseless electrical activity, elevated serum D-dimmer, and a markedly enlarged right ventricle chamber. After rescue thrombolytic alteplase therapy, the patient was successfully resuscitated and had a good neurological recovery.Keywords: cardiac arrest, pulmonary embolism, thrombolysis

The benefits and harms of dual antiplatelet therapy (DAPT) continuation with aspirin and clopidogrel beyond 1 year after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation for high ischemic or bleeding risk patients remain unclear. All consecutive patients undergoing PCI were prospectively included in the Fuwai PCI Registry from January 2013 to December 2013. We evaluated 7521 patients who were at high risk for thrombotic or hemorrhagic complications and were events free at 1 year after the index procedure. “TWILIGHT-like” patients with high risk of bleeding or ischemic events were defined by clinical and angiographic criteria. The primary ischemic outcome was major adverse cardiac and cerebrovascular events [MACCE] (a composite of all-cause death, myocardial infarction, or stroke). Median follow-up duration was 2.4 years. The risk of MACCE was significantly lower in DAPT>1-year group (n = 5252) than DAPT≤1-year group (n = 2269) (1.5% vs. 3.8%; hazard ratio [HR]: 0.37; 95% confidence interval [CI]: 0.27–0.50; P < .001). This difference was largely driven by a lower risk of all-cause death. In contrast, the risk of Bleeding Academic Research Consortium (BARC) type 2, 3 or 5 bleeding was statistically similar between the two groups (1.0% vs. 1.1%; HR: 0.80; 95% CI: 0.50–1.28; P = .346). Results were consistent after multivariable regression and propensity-score matching. Prolonged DAPT beyond 1 year after DES implantation resulted in a significantly lower rate of atherothrombotic events, including a mortality benefit, with no higher risk of clinically relevant bleeding in “TWILIGHT-like” patients who were at high-risk for ischemic or bleeding events.

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Although the limit cycle have been studied for more than 100 years, the existence of its Lyapunov function is still poorly understood. By considering a common limit cycle system, a puzzle related to the existence of Lyapunov functions for Limit cycle system is proposed and studied in this paper: The divergence is not equal to zero, while the trajectory can be infinite loop on limit cycle. It will be discussed from three aspects. Firstly, the definition of Lyapunov function is concerned, and a new version of definition is given which is equivalent to the usual one and better adapts to the properties of Lyapunov function. Secondly, two criteria(divergence and dissipation power) are discussed from the perspective of dissipation, and it reaches that they are not consistent in representing the dissipation. Thirdly, by studying the motion of charged massless particle in electromagnetic field, it obtains that the limit cycle is an isopotential line on which the charged particles can move infinitely. Such discussions above may provide an understanding on the puzzle about the existence of Lyapunov functions for limit cycle system., 21 pages,2 figures

A rigorous proof of a theorem on the coexistence of smooth Lyapunov function and smooth planar dynamical system with one arbitrary limit cycle is given, combining with a novel decomposition of the dynamical system from the perspective of mechanics. We base on this dynamic structure incorporating several efforts of this dynamic structure on fixed points, limit cycles and chaos, as well as on relevant known results, such as Schoenflies theorem, Riemann mapping theorem, boundary correspondence theorem and differential geometry theory, to prove this coexistence. We divide our procedure into three steps. We first introduce a new definition of Lyapunov function for these three types of attractors. Next, we prove a lemma that arbitrary simple closed curve in plane is diffeomorphic to the unit circle. Then, the strict construction of smooth Lyapunov function of the system with circle as limit cycle is given by the definition of a potential function. And then, a theorem is hence obtained: The smooth Lyapunov function always exists for the smooth planar dynamical system with one arbitrary limit cycle. Finally, by discussing the two criteria for system dissipation(divergence and dissipation power), we find they are not equal, and explain the meaning of dissipation in an infinitely repeated motion of limit cycle., Comment: 19 pages, 8 figures, regular paper

Carotid atherosclerosis is associated with many serious cardiovascular diseases; hence, it is necessary to identify factors related to its occurrence in order to develop preventive and therapeutic strategies. This study was conducted to identify risk factors associated with carotid atherosclerosis among the population residing in Northeast China. This epidemiological survey was conducted in a representative group of relatively healthy community residents. All participants answered questions about their medical histories and underwent physical examination, blood biochemical analysis, and ultrasonography examinations of their necks and abdomens. The prevalence rates of carotid atherosclerosis under different factors and conditions were then analyzed. The results of this study showed that age, gender, and diabetes significantly affected the prevalence of carotid atherosclerosis in this Northeast Chinese population. In addition, gender-based subgroup analysis revealed additional factors correlated with the prevalence of carotid atherosclerosis in men or women, although their correlations were not significant in the overall population. While high serum TC and LDL-C levels were risk factors for carotid atherosclerosis in men, it showed no clear correlation with the prevalence of carotid atherosclerosis in women. In contrast, the prevalence of carotid atherosclerosis in female participants with high serum TG level, hypertension, obesity and nonalcoholic fatty liver disease were higher than that of the control population, a trend not observed in male participants. Older age, male sex, and diabetes were independently associated with increased risk of carotid atherosclerosis in Northeast China. These findings could lead to improved screening for carotid atherosclerosis for better disease management.

The design of mechanism is used to calculate node reliability of incredible P2P network. The mechanism through matrix shows the trust relationship between nodes in the network, through matrix operation realizes the trust transfer process fast, and through a trusted server provides calculation service of trust degree for nodes in P2P network.

To create a professional e-commerce logistics business is gradually being attention by the e-commerce enterprises, an effective reverse logistics can not only reduce logistics costs, increase revenue, it is important to be able to achieve a better quality customer service. This paper focuses on e-commerce environment, from the characteristics of reverse logistics, e-commerce environment, described the reverse logistics process, and discusses the use of RFID technology to build reverse logistics system design.

It is not easy to solve the problem, which is solving business chain in the communication process sensitive data in XML security issues for XML signature, on the security of XML based on the study. This paper proposes XML-based data communications encryption technology model that enables the sender to encrypt and the overall signature, XML-based communication to achieve data security.

[Objective] In order to use knowledge management to improve the core competence of supply chain; [Methods] By forming a model to improve the core competence of supply chain; [process] By studying knowledge management and its system, the present paper confirms the specific knowledge characteristics of supply chain and its core competence, analyzes the mechanism and influential factors of knowledge mobility in supply chain and establishes a knowledge and value chain based model of improving the core competence of supply chain.

Objective: An intrusion detection system was constructed on the basis of the characteristics of BP neural network model. Methods: According to the capture engine of the text, all network data stream flowed through the systematic monitoring network segment will be captured, feature extraction module analyze and process the captured network data flow, you can extract complete and accurate eigenvector on behalf of this data stream, and this eigenvector will be presented to the neural network classification engine, as the input vector of a neural network Results: The neural network classification engine analyzes and processes this eigenvector, and thus distinguishes whether it is the intrusive action.

For TCP/IP Agreement has certain security bugs, the hacker catches the opportunity to attack the Network. On the basis of the analysis of the TCP/IP Agreement's vulnerability, the article has further analyzed the vulnerability of the Transport Layer Agreement, and discussed the security and the promotion method of TCP/IP Agreement's transport layer.

To prevent file transmission in the electronic military affair system from being damaged. Methods: security mechanisms of Web service based on J2EE platform, system security based on RSA algorithm, and the basic principle of digital signature. Procedure: to explain definition, characteristics and structure of the electronic military affair system, and to analyze its design process and security. Conclusion: identity authentication mechanism can be established based on digital signature scheme to ensure integrality and anti-negativity of file transmission in the electronic military training system.

In the study of computer-aided design of an antiaircraft gun system, by using Visual C++6.0 in the second development of Autocad 2010, it solves the technical difficulties in applying ARX application program in the process of compiling, debugging and connecting, which provides technological solutions for the digital control of old-style mechanical and electrical simulation antiaircraft weapon system.

With the development of the compressive sensing theory, the image reconstruction from the projections viewed in limited angles is one of the hot problems in the research of computed tomography technology. This paper develops an iterative algorithm for image reconstruction, which can fit most cases. This method gives an image reconstruction flow with the difference image vector, which is based on the concept that the difference image vector between the reconstructed and the reference image is sparse enough. Then the l1-norm minimization method is used to reconstruct the difference vector to recover the image for flat subjects in limited angles. The algorithm has been tested with a thin planar phantom and a real object in limited-view projection data. Moreover, all the studies showed the satisfactory results in accuracy at a rather high reconstruction speed.