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This work firstly established a one-to-one correspondence between a matrix and a natural number with Godel coding, by which it could judge two matrixes equality. Secondly, the work presented a secure protocol for computing matrix eigenvalues. Lastly, it proved the two protocols to be secure by simulation paradigm. Besides in the field of data outsourcing services, they have practical value with lower computational complexity and communication complexity. [ABSTRACT FROM AUTHOR]

Reports of decreasing PM 2.5 concentrations in some developed countries and regions, as well as the trends of annual average concentrations of PM 2.5 in the 74 key cities of China from 2013 to 2016 were analyzed. The cities were categorized based on PM 2.5 concentration ranges and the regions where they are located. The average annual declining rates of PM 2.5 concentration were calculated for these categories. Based on previous PM 2.5 rates, we proposed different scenarios of decreasing PM 2.5 concentration in Chinese cities for the future decades. Future PM 2.5 concentration was calculated for each of the Chinese cities, and the milestones for 31 provinces and key areas were analyzed. The results showed that the annual average concentration of PM 2.5 in China could meet the national air quality standard by 2025 and drop below 30 μg·m -3 in 2030 under both scenarios. The PM 2.5 concentration in Beijing-Tianjin-Hebei and surrounding areas could meet the standards in 2030, and the Yangtze River Delta area in 2025. It will be difficult for Beijing, Tianjin, Hebei, and Henan to meet the standard in 2030. Even in the scenario where measures were intensified in the key areas, the cities failed to meet the PM 2.5 concentration standards. In Beijing-Tianjin-Hebei and surrounding areas, the values were close to 40% of the target by 2030. To accelerate the reduction of PM 2.5 concentration, extreme efforts will be needed in the highly polluted areas.

Y chromosomal short tandem repeat (Y-STR) typing is the most commonly used genetic technique in forensic studies. However, there may be a limit to the application of Y-STR in forensic science as Y-STR loci are subject to loss or variation caused by the higher chromosomal structures' spontaneous mutation rate. Located in the long arm of the Y chromosome, azoospermia factor (AZF) have been shown to participate in spermatogenesis and its deletion could cause infertility. However, little is known about the Y-STR dropout pattern in individuals with Y chromosome microdeletions. In this study, 85 infertile males with Y chromosome interstitial deletion were identified and special Y-STR allele dropout patterns were analyzed by employing a Y-STR Commercial Kit and a Y chromosome Deletion Kit. Results demonstrate that AZF a region deletion are related to DYS439-DYS389I-DYS389II alleles dropout, while AZF b region or c region deletions correlate to DYS448 allele dropout. Null DYS385-DYS392-DYS448 alleles were observed in AZF b+c+d region deletion individuals. While null DYS390-Y-GATA-H4-DYS385-DYS392-DYS448 alleles were observed in AZF a+b+c+d large region deletion individuals. Our data suggest that Y chromosome microdeletions may indicate specific Y-STR locus dropout patterns.

Objectives: To study the rat brain trauma injury model and investigate the rules of transformation of expression of synaptophysin and its relationship between histology and radiology alternation after brain trauma injury., Methods: 24 SD male rats aged three months were randomly divided into 4 groups,including a control group of 6 rats.The experimental group rats were received operation to build free falling brain trauma injury model.The rat were analyzed at 2,4,8 weeks after injury.The experimental group rat were killed after CT scan and functional evaluation,histological changes were measured through HE staining.Synaptophysin were observed by using immunofluorescence method and Western blot., Results: After brain injury the functional evaluation of rat showed dysneuria.Edema and necrosis in neurons and local congestion at 24 h after injury,necrosis and solubility liquefaction at 2 weeks after injury,and histological defects at 4 weeks and 8 weeks after injury,were observed in HE staining in experimental group.The significant cerebral low density shadows at 24 h after injury,lightened in 2 weeks after injury,and disappeared at 4 weeks and 8 weeks after injury,left only the bone defects in CT images.Expression of synaptophysin in brain tissue was decreased from 2 weeks after injury and it was mild increased at 8 weeks after injury evaluated by immunofluorescence method and Western blot., Conclusions: The functional evaluation,histological and CT scan result indicate that we have built the rat brain trauma injury model successfully.The damage of synapse was correlated with histological and radiological result.The expression of synaptophysin was decreased form acute stage and gradually increased until 8 weeks after injury.This study can be applied as control in research of nerve regeneration after brain trauma injury.

In order to improve the accuracy and stability of the rebuilt spectrums, it is necessary that stability analysis and nicety measuring of the maximum optical path difference of interferograms in the photo-elastic modulator Fourier transform spectrometers(PEM-FTS). The maximum optical difference of interferograms is uncertain parameter, and it is relate to the resonant state, characteristic of frequency-thermal drift and driving voltage of PEM. Therefore, based on the principle of photo-elastic modulator Fourier transform interferometer, the model of the freguency-thermal drift is built, and the variety of the maximum optical path difference is analyzed; A measuring method of the maximum optical path difference is put forward, which is zero-crossing counting of laser's interference signal when the driving signal of PEM is as the standard. In the method the dual channel high-speed comparator and FPGA are used to transform sine wave to square wave, to realize zero-crossing trigger counting and errors compensation. On the condition that the 670. 8 nm laser is as the power source to produce the reference interferograms by the PEM interferometer, the 77. 471 µm maximum optical path difference could be measured by the zero-crossing counting the measuring errors is less than 0. 167 nm, the rebuilt spectral peak wavelength errors of the infrared blackbody is less than 2 nm. the result is content with PEM-FTS.

In order to enhance the spectrum resolution of current photo-elastic modulator-based Fourier transform spectrometer, a multi-reflected photo-elastic modulator-based interferometer structure was proposed in the present paper. Through coating reflecting film alternatingly on the photo-elastic crystal and light oblique incidence, and allowing the incident ray to have the multi-reflection in the crystal and exit from the other side of the crystal, the authors increased the light propagation distance in the crystal and enhanced the optical path difference at last. Based on this, the function of interference-spectrum retrieval was established, the optical system matched to the multi-reflected PEM-based interferometer was designed, and finally, the experimental system of multi-reflected PEM-based Fourier transform spectroscopy for telemetry was established. The principle of verification tests by using 671 nm laser and xenon lamp shows that the interferogram was clear and stable, and the feasibility of the principle of the system was verified. The expected result shows that the spectrum resolution of the designed PEM-FTs with multi-reflection achieved 13 cm(-1), and its luminous flux just didn't reduce too much, which ensured the SNR. Through spectral inversion of the interference fringes, the technical feasibility of the spectrum system developed was verified. This work established the basic condition of prototype fabrication, radiation precise calibration, spectral calibration and instrument signal-to-noise ratio test and so on.

In order to achieve the incoming laser's accurate position, it is necessary to improve the detected laser's direction resolution. The InGaAs focal plane array detector with the type of FPA-320 x 256-C was selected as the core component of the diffraction grating laser warning device. The detection theory of laser wavelength and direction based on diffraction grating was introduced. The drive circuit was designed through the analysis of the detector's performance and parameters. Under the FPGA' s timing control, the detector's analog output was sampled by the high-speed AD. The data was cached to FPGA's extended SRAM, and then transferred to a PC through USB. Labview on a PC collects the raw data for processing and displaying. The imaging experiments were completed with the above method. With the wavelength of 1550 nm and 980 nm laser from different directions the diffraction images were detected. Through analysis the location of the zero order and one order can be determined. According to the grating diffraction theory, the wavelength and the direction of the two-dimensional angle can be calculated. It indicates that the wavelength error is less than 10 nm, and the angle error is less than 1 degrees.

For temperature drift in hypervelocity photoelectric modulation interferometer, a control model of temperature compensation is presented including voltage and phase compensation. First, according to the similar and modeling theory, an equivalent circuit model of mechanical properties of hypervelocity photoelectric modulation interferometer was established, the impact of temperature drift on its resonance frequency was analyzed, a mathematical model was set up, which contains drive voltage, frequency and resonance frequency, and the control method was determined for high optical path difference to get steady. Then, a digital method including voltage and phase compensation is given for optical path difference deviation control, which merges the DPLL and program of voltage and phase compensation. Finally, the control method was tested through experiment system. A test between drive control system including voltage and phase compensation and traditional drive control system was executed, using a laser doppler vibrometer to record the amount of change in optical path difference within 3 hours. Results show that the optical path difference deviation caused by temperature drift in long term is reduced by about 50%.