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Objective: To evaluate the effect of comprehensive schistosomiasis control measures based on infection source control in Hanchuan City (marshland and lake endemic regions)., Methods: The data of comprehensive schistosomiasis control in Hanchuan City from 2004 to 2013 were collected, and the change trends of the Oncomelania hupensis snail status and the infection situation of human and livestock were analyzed to evaluate the control effect., Results: After the implementation of the comprehensive measures, the infection rates of residents and cattle decreased from 6.38% and 8.11% in 2004 to 0.16% and 0 in 2013 respectively. There were no acute schistosomiasis patients since 2007, no new infection cases since 2011, and no infected snails since 2012. Compared with 2004, the occurrence rate of frames with living snails and the average density of living snails decreased by 56.78% and 68.35%, respectively, but the snail area and susceptible area increased by 0.62% and 7.10%, respectively. In 2013, all the 367 endemic villages in 26 townships reached the criteria of transmission controlled., Conclusions: The comprehensive schistosomiasis control measures based on infection source control can control the schistosomiasis transmission effectively in marshland and lake endemic regions. When consolidating the achievement, the snail area in inner embankment should be compressed to prevent the schistosome re-infection in human and livestock.

Objective: To compare the schistosomiasis control effects of the comprehensive control measures based on infectious resources control and the conventional control measures, so as to provide the evidence for improving prevention and control strategies., Methods: In the Hanbei River basin, the comprehensive control measures based on infectious resources control (conventional measures plus grazing prohibition in the marshland, machine instead of cattle, and marshland development, and so on) were carned out, and in the Nanzhi River basin, the conventional control measures were performed. The schistosomiasis epidemic data were collected, analyzed and compared from 2004 to 2011., Results: In 2004, the infection rate of the populations and cattle in Nanzhi River basin was lower than that in the Hanbei River basin. From 2004 to 2011, the Oncomelania hupensis snail frame occurrence rate and the average density of living snails in the Nanzhi River basin was lower than that in the non-ploughing marshland and preventing wave woods of the Hanbei River basin, and there were schistosome infected snails in the Nanzhi River basin. From 2008 to 2010, there were no infected snails in the non-ploughing marshland of the Hanbei River basin. From 2007, the cattle have been eliminated in the Hanbei River basin. From 2007 to 2011, there were no infected snails in the preventing wave woods of the Hanbei River, but there were schistosome infected cattle found by stool examinations every year in the Nanzhi River basin. From 2004 to 2011, the infection rates of population presented downward trends in the two river basins, but the downward trend was more significant in the Hanbei River basin than in the Nanzhi River basin., Conclusion: The conventional control measures and comprehensive control measures based on infectious resources control are both effective, but the latter is more effective.

Objective: To evaluate the effect of a novel plant molluscicide "Luo-wei" (Tea-seed distilled saponins, TDS) against Oncomelania hupensis in the field of lake areas in Hanchuan City, Hubei Province., Methods: Immersing experiment and spraying experiment were carried out in 5 ditches and a beach land respectively in Hanchuan City, Hubei Province to compare the molluscicidal effects among 4% TDS, 50% wettable powder of niclosamide ethanolamine salt (WPN), and 26% suspension concentrate of metaldehyde and niclosamide (MNSC) by different dosages and time. The chi2 test or Fish's exact test was used to examine the differences of snail death rates among them., Results: After 72 h of immersing experiment, the snail death rates in the 2.5 g/m3 TDS group, 3.0 g/m3 TDS group, 2.0 g/m3 WPN group and 2.0 g/m3 MNSC group were 99.33%, 100%, 100%, and 100%, respectively, and there was no significant difference among them (P > 0.05). By the end of 15 d after the spraying experiments, the snail death rates were 91.86% in the 2.0 g/m2 MNSC group, 90.26% in the 5.0 g/m2 TDS group, 87.45% in the 2 g/m2 WPN group, and 86.10% in the 3 g/m2 TDS group. The differences between the 5.0 g/m2 TDS group and 2.0 g/m2 MNSC group, as well as the 3.0 g/m2 TDS group and the 2.0 g/m2 WPN group had no statistical significance (both P > 0.05)., Conclusions: The molluscicidal effect of TDS is similar to that of WPN or MNSC. The recommended dosage of TDS is 2.5 g/m3 for immersing or 5 g/ m2 for spraying in the field.

The template selection is essential in the application of digital micromirror spectrometer. The best theoretical coding H-matrix is not widely used due to acyclic, complex coding and difficult achievement. The noise ratio of best practical S-matrix for improvement is slightly inferior to matrix H. So we designed a new type complementary S-matrix. Through studying its noise improvement theory, the algorithm is proved to have the advantages of both H-matrix and S-matrix. The experiments proved that the SNR can be increased 2.05 times than S-template.

A MOEMS micro-mirror spectrometer, which uses micro-mirror as a light switch so that spectrum can be detected by a single detector, has the advantages of transforming DC into AC, applying Hadamard transform optics without additional template, high pixel resolution and low cost. In this spectrometer, the vital problem is the conflict between the scales of slit and the light intensity. Hence, in order to improve the resolution of this spectrometer, the present paper gives the analysis of the new effects caused by micro structure, and optimal values of the key factors. Firstly, the effects of diffraction limitation, spatial sample rate and curved slit image on the resolution of the spectrum were proposed. Then, the results were simulated; the key values were tested on the micro mirror spectrometer. Finally, taking all these three effects into account, this micro system was optimized. With a scale of 70 mm x 130 mm, decreasing the height of the image at the plane of micro mirror can not diminish the influence of curved slit image in the spectrum; under the demand of spatial sample rate, the resolution must be twice over the pixel resolution; only if the width of the slit is 1.818 microm and the pixel resolution is 2.2786 microm can the spectrometer have the best performance.

A new type micro Hadamard transform (HT) near-infrared (NIR) spectrometer is proposed in the present paper. It has a MOEMS (Micro-Opto-Electro-Mechanical Systems) blazed grating HT mask. It has merits of compactness, agility of dynamic mask generation and high scan speed. The structure and theory of this spectrometer are analyzed. The 63-order Hadamard-S matrix and mask are designed. The mask is dynamically generated by program of MOEMS blazed gratings. The spectrum is in agreement with that measured by Shimadzu spectrometer in experiments. It has a wavelength range between 900 and 1 700 nm, spectral resolution of 19 nm, single scan time of 2.4 s, SNR of 44.67:1, optical path of 70 mm x 130 mm, and weight under 1 kg. It can meet the requirement of real time detection and portable application.

Projection display devices are undergoing a period of multi-development, and with the maturation of MEMS technology, which leads to MEMS-based light modulators for display applications, have become one of the research focuses. The structure of MEMS-based grating moving light modulator (GMLM) is composed of the reflection plate, address electrode and four cantilevers, and movable grating plate, which is supported by four crab-cantilevers placed around, and is actuated like a piston by electrostatic force. The piston-type motion of grating can be used to modulate the phase of incident light. The micro-distance between the upper surface of movable grating and underlying reflector is a key parameter and is important to GMLM performance. Traditional measurement method such as step-machine would destroy the device; while a high accuracy and non-contact measurement machine called KYKO White Light Interferometer is expensive. In the present paper, the GMLM optical principle using scalar diffraction theory was in details analyzed. A novel non-contact wavelength scanning spectrum analysis method was put forward to measure the distance between the upper surface of movable grating and underlying reflector. The U-4100 spectrophotometer was adopted to gain spectrum information; while the spectrum analysis method using peak wavelength position was introduced to calculate the micro distance. The measurement result is consistent to theoretical result. The micro-distance is 1.131 3 microm using such non-contact wavelength scanning spectrum analysis method, while it is 1.240 0 microm with WYKO White Light Interferometer. The relative error was lower than 1%, compared with the results measured by WYKO White Light Interferometer, and the method has good repetition ability and is cheap with RMB50 Yuan each time. Furthermore, measuring pull-in voltage, resonance frequency and micro distance in MEMS-based diffraction and interference devices was proposed completely based on such non-contact wavelength scanning spectrum analysis method.