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The availability of ZY-3 satellite data provides additional potential for surveying, mapping, and quantitative studies. Topographic correction, which eliminates the terrain effect caused by the topographic relief, is one of the fundamental steps in data preprocessing for quantitative analysis of vegetation. In this paper, we rectified ZY-3 satellite data using five commonly used topographic correction models and investigate their impact on the regression estimation of shrub forest leaf biomass obtained from sample plots in the study area. All the corrections were assessed by means of: (1) visual inspection (2) reduction of the standard deviation (SD) at different terrain slopes (3) correlation analysis of different correction results. Best results were obtained from the Minnaert+SCS correction, based on the non-Lambertian reflection assumption. Additional analysis showed that the coefficient correlation of the biomass fitting result was improved after the Minnaert+SCS correction, as well as the fitting precision. The R2 has increased by 0.113 to reach 0.869, while the SD (standard deviation) of the biomass dropped by 21.2%. Therefore, based on the facts, we conclude that in the region with large topographic relief, the topographical correction is essential to the estimation of the biomass.

The ZiYuan-3 (ZY-3) remote sensing satellite is China's first civilian high-resolution stereo mapping satellite. Because the interior orientation parameters measured before launch are biased, the multispectral (four-band) images collected by ZY-3 exhibit low-accuracy band-to-band registration, which affects their subsequent applications. This paper presents a valid method for interior orientation determination of the ZY-3 multispectral sensor by determining the look angles of the charge-coupled device arrays for all bands. One band is chosen as the benchmark band, and its interior orientation is determined using the relevant ZY-3 image collected over the calibration field and the corresponding digital orthoimage map and digital elevation model. The remaining bands are then calibrated using the benchmark band as control data. The quality of the calibration is further enhanced by shortening the calibration period and by combining images collected over different calibration fields, which decreases the negative effects of errors in the satellite's attitude and position data. The interior orientation of the multispectral sensor in ZY-3 was determined using data sets taken over two calibration fields, namely, Dengfeng (Henan Province) and Tianjin. Evaluation experiments were performed using ZY-3 multispectral images and ground control points (GCPs) collected over several different periods and areas. The positioning accuracy of the ZY-3 multispectral images with a limited number of GCPs after calibration of the interior orientation was better than 0.3 pixels, and the band-to-band registration accuracy was up to 0.15 pixels. [ABSTRACT FROM PUBLISHER]

The present study was designed to establish transgenic Eimeria mitis (tE. mitis) expressing chicken interleukin-4 (ChIL-4) and further exploitation of tE. mitis as a novel vaccine vector to control coccidiosis. For this purpose we compared the clinico-hematological alterations induced by wild type and tE. mitis carrying ChIL- 4 in broilers birds. Wild type E. mitis (wE. mitis) oocysts were nucleofected with double cassette vector and transgenic oocysts were propagated for stable transfection. Stability of the transfected E. mitis was observed by fluorescent microscopy and PCR analysis revealed the appearance of 411bp band suggestive of presence of IL-4 into the genome of tE. mitis. Birds inoculated with transgenic EmiChIL-4 excreted fewer oocysts and fecundity potential of tE. mitis turned out to be significantly lower than that of the wild type parent strain. Moderate clinical and behavioral signs such as restlessness, diarrhea, emaciation, decreased feed intake and loss of body weight was observed in birds inoculated with wE. mitis oocysts. The erythrocyte counts, Hb conc, PCV and MCHC decreased in birds infected with wE. mitis as compared to those infected with tE. mitis. The total leukocyte count including heterophils, eosinophil and basophils increased while lymphocytes were decreased in birds inoculated with wE. mitis as compared to birds in control group and those infected with tE.mitis. It was concluded that tE. mitis incorporated with ChIL-4 functions well as an adjuvant, conferring reduced fertility and compromised pathogenicity of tE. mitis. This discrimination, may be applied as a potential vaccine vector to control coccidiosis as well as pathogens from which antigens are expressed by tE. mitis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Advancements have been made in the genetic manipulation of apicomplexan parasites. Both the in vitro transient and in vivo stable transfection of Eimeria tenella have been developed successfully. Herein, we report the transient and stable transfection of Eimeria mitis. METHODS AND FINDINGS: Sporozoites of E. mitis transfected with enhanced yellow fluorescent protein (EYFP) expression plasmid were inoculated into chickens via the cloacal route. The recovered fluorescent oocysts were sorted by fluorescence activated cell sorting (FACS) and then passaged 6 generations successively in chickens. The resulting population was analyzed by genome walking and Western blot. The endogenous development of the transgenic E. mitis was observed and its reproduction potential was tested. The stable transfection of E. mitis was developed. Genome walking confirmed the random integration of plasmid DNA into the genome; while Western blot analysis demonstrated the expression of foreign proteins. Constitutive expression of EYFP was observed in all stages of merogony, gametogony and sporogony. The peak of the transgenic oocyst output was delayed by 24 h and the total oocyst reproduction was reduced by 7-fold when compared to the parental strain. CONCLUSION: Stable transfection of E. mitis was successfully developed. The expression of foreign antigens in the transgenic parasites will facilitate the development of transgenic E. mitis as a vaccine vector.