Rolling bearing fault diagnosis based on fine-grained multi-scale Kolmogorov entropy and WOA-MSVM.

In allusion to solve the issue of fault diagnosis for bearing and other rotatory machinery, a technique based on fined-grained multi-scale Kolmogorov entropy and whale optimized multi-class support vector machine (abbreviated as FGMKE-WOA-MSVM) is proposed. Firstly, vibration signals are decomposed by fine-grained multi-scale decomposition, and the Kolmogorov entropy of the sub-signals at different analysis scales is calculated as the multi-dimension feature vector, which quantitatively characterize the complexity of the signal at multi-scales. Aiming at the problem of sensitive parameters selection for multi-class support vector machine model (abbreviated as MSVM), the whale optimization algorithm (abbreviated as WOA) is introduced to optimize the penalty factor and kernel function parameter, and constructing optimal WOA-MSVM model. Finally, an instance analysis is carried out with Jiangnan University bearing datasets to verify the effectiveness and superiority of this technique. The results show that compared with different feature vectors and models such as K nearest neighbors (abbreviated as KNN) and Decision Tree (abbreviated as RF), the proposed technique is superior with fast computation speed and high diagnostic efficiency.

Contributions to the lymphatic filariasis elimination programme and post-elimination surveillance in China by NIPD-CTDR.

China was once one of the most heavily endemic for lymphatic filariasis (LF), with a heavy disease burden. Due to decades of sustained efforts, LF was eliminated from China in 2007. The historical tales in the control and elimination of LF in China and current post-elimination surveillance are reviewed and concluded. In the course of LF control and elimination, National Technical Steering Group for Filariasis Control and Research, and Collaborating Research Group on the Transmission Threshold of Filariasis, led by the National Institute of Parasitic Diseases, carried out researches, developed control measures, and applied in practical control and surveillance. The main of the results include: in theoretical study, (1) formulating the microfilaria rate below 1% as the transmission threshold of filariasis, (2) developing anti-filarial drugs and establishing animal model for drug screening, (3) studying the vectorial capacity of mosquitoes transmitted filariasis; in clinical diagnostic and therapy, (1) developing antigens for serological diagnostics, (2) studying different administration regimes for alleviating the side-response of diethylcarbamazine (DEC), (3) studying on the recurrence of acute adenolymphangitis and lymphadenitis of malayan filariasis, (4) observing lymphoedema of the lower extremity using lymphangiography; in practical control and surveillance, (1) establishing the control strategy taking elimination of infection source as the major focus, (2) formulating safe, feasible and effective DEC-mass drug administration, (3) revealing the transmission pattern of filariasis at the post-control phase, (4) establishing comprehensive active surveillance system, (5) formulating the criteria of basic elimination and elimination of filariasis. In the post-elimination surveillance phase, special monitoring and investigation in key areas were conducted for clearing way potential residual infection sources. Two schemes on LF surveillance in the post-elimination phase and caring for chronic filariasis patients were issued to maintain the diagnosis and treatment skills of filariasis all levels of disease control and prevention workers in future. Also, the Notifiable Diseases Reporting System, which included LF in 2004, plays an important role in LF post-elimination surveillance to prevent LF resurgence in China. The strategies and measures of LF control, elimination and post-elimination surveillance in China provide valuable practical experience and promote the progress of Global Programme of Elimination of Lymphatic Filariasis in worldwide.

Orientation and Microstructure Evolution of Al-Al2Cu Regular Eutectic Lamellar Bifurcating in an Abruptly Changing Velocity under Directional Solidification.

In an abruptly changing velocity under directional solidification, microstructures and the growth orientation of Al-Al2Cu eutectic lamellar were characterized. The change in solidification rate led to an interfacial instability, which results in a bifurcation of the eutectic lamella into new, refined lamellae. The growth orientation of the eutectic Al2Cu phase was also only in its (001) direction and more strongly oriented to the heat flow direction. The results suggest that the eutectic lamellar Al-Al2Cu bifurcation and the spacing adjustment may be caused by the rate determining lateral diffusion of the solutes after interfacial instability.

[Assessment of Serum IgG and Its Subclasses in Cystic Echinococcosis Patients and Its Application for Diagnosis].

OBJECTIVE: To assess the diagnostic performance of hydatid cyst fluid (HCF) in detecting the anti-HCF IgG and its subclasses IgG1, IgG2 and IgG4 in serum of cystic echinococcosis patients. METHODS: ELISA was used to measure IgG and its subclasses IgG1, IgG2, and IgG4 specific for Echinococcus granulosus HCF, in the sera of 37 cystic echinococcosis (CE) patients and 29 healthy subjects in Huan County, Gansu Province. The receiver operating characteristic (ROC) curves of the four antibodies were analyzed by MedCalc software, referenced with the gold-standard B ultrasonic imaging. The diagnostic performances between the four antibodies were compared using paired z statistics based on the areas under the curve (AUC), and the best diagnostic threshold was determined for each. The sensitivity and specificity for detecting the four types of antibodies were compared using Chi-square test. RESULTS: The AUCs for IgG and its subclasses IgG1, IgG2, and IgG4 were 0.722, 0.919, 0.712, and 0.835, respectively; the AUC of IgG1 was significantly higher than those of IgG (z = 3.629, P < 0.05) and IgG2 (z = 3.292, P<0.05). The sensitivity for detecting IgG, IgGl, IgG2, and IgG4 was 54.1%, 91.9%, 67.6%, and 75.7%, respectively; the sensitivity for IgGl was significantly higher than that for IgG (χ2 = 3.84, P < 0.05), IgG2 (χ2 = 6.80, P < 0.05), and IgG4 (χ2 = 10.16, P < 0.05). The specificity for the four antibodies was 89.7%, 82.8%, 72.4%, and 89.7%, respectively, and no significant difference was found between them. In addition, the sensitivity for detecting IgG4 antibody was significantly higher in CE I-III than in CE IV-V patients. CONCLUSION: The IgG1 antibody shows the highest detection sensitivity by HCF, thus having potential value in diagnosis of cystic echinococcosis.

Confirmation of elimination of lymphatic filariasis by an IgG4 enzyme-linked immunosorbent assay with urine samples in Yongjia, Zhejiang Province and Gaoan, Jiangxi Province, People's Republic of China.

A sensitive and specific IgG4 enzyme-linked immunosorbent assay (ELISA) with urine samples has been reported. To confirm elimination of bancroftian filariasis, the ELISA was used in a study conducted in Yongjia County and Gaoan City, People's Republic of China, where filariasis elimination was declared, with 10,409 students 5-16 years of age. The antibody positive rates were 0.08% in Yongjia and 0.34% in Gaoan. All positive samples were re-examined and found to be negative. Our results show that this ELISA is practical and useful for confirmation of the elimination of filariasis. If similar results are obtained in different filariasis-endemic countries, this method may be useful in global filariasis elimination programs.

[Density fluctuation of microfilariae and the role of residual infection source in filariasis transmission after its interruption].

OBJECTIVE: To investigate the density fluctuation of microfilariae, persistence of microfilaremia and possible new infection due to residual microfilaremia in areas with filariasis transmission interrupted. METHODS: The observation site was made in a village of Jishou City, Hunan Province. Inhabitants were regularly examined by thick blood smear and the density fluctuation of residual microfilaremia in known and newly-found cases were followed up. With a consent from the cases with residual microfilaremia, no treatment was given until they naturally turned negative. Antifilarial antibody level was detected by IFAT and a test kit for filariasis-special IgG4. Culex quinquefociatus was dissected to determine the natural infection rate and density of III stage filarial larvae in transmission season. The identified cases were followed-up by interviews and physical examinations to see if clinical manifestations appeared. RESULTS: Blood examination was carried out for all inhabitants for 10 times, 4 cases with microfilaremia, including 3 cases found at the beginning of the project and one newly infected case, were discovered after the interruption of filariasis transmission in the 19-year period. Among the 4 cases followed up, one case naturally turned negative within 7 years, one case became negative in the 9th year but returned positive in the 12th year, and then naturally turned negative in the 13th year. The 3rd case turned negative in the 14th year and was again positive in the 19th and the 20th years, and became negative through diethylcarbamazine (DEC) treatment in the 21st year. The new case was found to have microfilaremia in the 16th year and kept positive for 5 years until DEC treatment. Serological tests (IFAT and special IgG4) revealed no new positive cases. The natural infection rate and larvae density in Culex quinquefasciatus decreased annually. Conclusion The persistence period of residual microfilaremia in individual cases might last for more than 20 years after filariasis transmission has been interrupted.