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An epidemic model with two parallel infectious stages and time delays and pulse vaccination is proposed. We introduce four thresholds and further obtain the conditions that the disease will be extinct or not. Corollaries show that under condition that θ > max { θ ∗ 1 , θ ∗ 2 } the disease will fade out, and if θ < min { θ 1 ∗ , θ 2 ∗ } , the disease will be endemic. Our results indicate that a larger pulse vaccination rate will lead to the eradication of a disease. Furthermore, two thresholds ℜ ∗ 1 and ℜ ∗ 2 show that the diversity of the contagiousness affects the basic properties of these models. In addition, numerical results indicate that the probability for an infected individual to enter different infective compartments greatly affects two infective compartments. [ABSTRACT FROM AUTHOR]

In recent years, frequent urban drinking water contamination accidents have caused significant impacts on society in China. However, emergency measures are primarily realized as management policies lack systematic technologies especially for those within-network contamination accidents. The aim of this paper is to perform analysis on cases of contaminant accidents that occurred in water distribution networks and to propose a framework of emergency response technologies. The causes, impacts, and characteristic trends of urban water supply contamination accidents are analysed according to the data of eighteen typical contamination cases that have been publicly reported in China since 2003. The results show that the main problems for rapid response to those accidents are: (1) limited monitoring means; (2) lag in response, especially the lag in providing an explanation to the public; and (3) lag in recovery from the accident. To solve those problems, a framework of technological strategy for rapid response to contamination accidents including monitoring, identifying, evaluation, isolation and flushing is then proposed. Since drinking water contamination accidents are not a unique problem that only happens in China, the response policy and related technologies proposed in this paper are also applicable to other countries and regions that face the same problems. [ABSTRACT FROM AUTHOR]

ABSTRACTThe 23-valent pneumococcal polysaccharide vaccine (PPSV-23) is the only approved vaccine for pneumococcal diseases in elderly Chinese population. Though regional studies explored the PPSV-23 vaccination coverage rates and influencing factors in China, a large-scale, nation-wide epidemiological surveillance studies to understand the different factors impeding pneumococcal vaccination rate are required. Hence, this review summarized PPSV-23 coverage rate, analyzed and identified vaccination influencing factors among elderly population across China by exploring articles published in CNKI, Wanfang and PubMed databases. Pneumococcal vaccination coverage rate was found to be low at around 1.23%~42.10% in China. Co-morbidities, knowledge, attitude, perception toward pneumonia and PPSV-23, education level, socio-economic disparities, health education and local policies were some of the factors associated with vaccination willingness among elderly Chinese population. Interventions or policies like government funding, subsidies, inclusion of PPSV-23 in medical insurance, or systematic encouragement from HCPs as key strategies should be implemented to encourage vaccination.

Abstract: Objective: To understand the role of mitochondrial DNA (mtDNA) in carcinogenesis. Methods: single-step method was used to isolate the mtDNA from human lung adenocarcinoma cell line SPC-A-1. The mtDNA was analyzed by restriction fragment length polymorphism (RFLP) with 11 kinds of restriction endonuclease, which were Pvu II, Xho I, Pst I, EcoR I, BstE II, Hind III, Hpa I, Bc1 I, EcoR V, Sca I and Xba I. Restriction map of mtDNA from SPC-A-1 cell was obtained by the single and double-digestion method. Results: It was found that no variation at 32 restriction-sites could be detected in the coding region of mtDNA from SPC-A-1 cell line. But a new site was found at nucleotide 16276 (EcoR V) within the noncoding region. Conclusion: These results indicate that the primary structure of gene coding region of mtDNA isolated from SPC-A-1 cell is highly stable. While the major variation of nucleotide is probably located in the noncoding region.

Abstract:The Tongkuangyu metaporphyry copper deposit formed in the Early Proterozoic is tectonically located in the northern part of the Zhongtiao Λ‐type palaeorift depression, on the southern margin of the North China platform. The genesis of the deposit has long been a hot subject of research of geologists working on mineral deposits. By means of the protolith reconstruction and fluid inclusion and isotope studies of host rocks of the deposits, the authors hold that this deposit is the product of combined exogenic, endogenic and metamorphic processes. Its formation mainly involved the following four stages: (1) the stage of formation of Mg‐ and Fe‐rich tuffaceous variegated cupriferous sand‐shale and K‐rich biomodal volcanic rocks; (2) the early stage of formation of the metaporphyry copper deposit; (3) the stage of formation of the metaporphyry copper deposit; and (4) the stage of reworking of the metaporphyry copper deposit.

The progress in computer sciences and information technology provides more teaching modes. Recently, the microlecture has drawn extensive attentions, which could make the knowledge points clear in a shorter teaching time than traditional ways. In addition, it is not limited by time and space. This study makes some explanations and discussions on microlecture in order to apply it to higher normal education. First, the basic concept of microlecture is presented to explain the background. Afterwards, the teaching mode and advantages of microlecture are discussed. Accordingly, its potential in higher normal education can be inferred. Finally, some feasible ways are suggested to apply microlecture to the higher normal education. Conclusions are drawn based on all these analyses. And it is promising that microlecure could make contributions to the teaching reform of higher normal education.

In this paper a kind of missile Electric-Servo-Actuator system is studied, using Matlab Simulink software to electric servo system is analyzed in the modeling and simulation. The system is superior to conventional PID controller with the fast and accurate response, small overshoot, good dynamic performance and steady-state performance. The adopted (fuzzy) PID control parameter design to improve the response and signal tracking performance of the system has the guide meaning to the design of the actual system.