Hyperspectral Estimation of Corn Fraction of Photosynthetically Active Radiation

Fraction of absorbed photosynthetically active radiation （FPAR） is one of the important variables in many vegetation productivity and biomass estimation models. Therefore, it is significant to retrieve FPAR accurately for the improvement of model precision. On the basis of the field experiment, this article analyzed the correlations between corn canopy FPAR and spectral reflectance, and reflectance derivative. Discussion about the mechanism of FPAR estimation with different empirical models is based upon corn canopy reflectance, reflectance derivative, NDVI （normalized difference vegetation index） and RVI （ratio vegetation index）. The reflectance of visible bands showed much better correlations with FPAR than near-infrared bands. The correlation between FPAR and reflectance derivative varied more frequently and greatly than that between FPAR and reflectance, and with preferable correlation only around 520, 570, 670, 805, 950, and 1 010 nm. Reflectance and reflectance derivative both had intimate correlation with FPAR at some typical single band, with the maximum R^2 of 0.791 and 0.882, respectively. In a word, reflectance derivative and vegetation index were much effective in the estimation of corn FPAR than reflectance, and the stepwise regression of multibands with reflectance derivative showed the best regression with R^2 of 0.944. Reflectance at 375 and 950 nm with absorption characteristics caused by water showed prodigious potential for FPAR precisely estimating model establishment. On the whole, vegetation index and reflectance derivative had good relationships with FPAR, and could be used for FAPR estimation. It would be effective for choosing right bands and excavating the hyperspectral data to improve FPAR estimating precision.     

Effects of Ultraviolet Radiation on Skeleton Development of Broiler Chickens

Seven hundred and twenty one-day-old AA broiler chickens were randomly allocated into two groups （male and female for half）, and put into two identical closed houses with different lighting programs. The first house was illuminated by using common incandescence light, and the second one was added with ultraviolet radiation light from the second week onwards. The birds lived in a floor with litters and free access to feed and water. Temperature, humidity and immune programs in the two houses were similar. The results showed that under ultraviolet radiation, the growth speed of skeleton increased （the shank length was significantly increased in the third week, P〈0.05; the leg muscle weight was significantly improved by 3.87%, P〈 0.05）; the skeleton quality improved （the density of skeleton mineralization was significantly increased by 6.11%, P 〈 0.01; serum calcium, phosphorus, and alkaline phosphatase activity were all improved）; and the growth performance was improved （feed conversion ratio was improved by 1.4% averagely; the uniformity of body weight, the shank length, the inclined body length and body height were significantly improved） in broiler chicken.     

Radiation response of connexin 43-transfected cells in relation to the “contact effect”

Radiation response of connexin 43-transfected cells in relation to the “contact effect”...     

In Situ Determination of Iron Distribution and Oxidation State in Broiler Duodenal Wall by Synchrotron Radiation μ-XRF and μ-XANES

Micro-X-ray fluorescence (μ-XRF) and micro-X-ray absorption near edge structure (μ-XANES) have not been widely used in animal nutrition.In situ determination of iron distribution and oxidation state in broiler duodenal wall was done by μ-XRF and μ-XANES techniques.Fifty newly hatched healthy (1-day-old) Arbor Acres commercial male broilers were used in this experiment.The chicks were fed a corn-soybean meal basal diet (96.00 mg of Fe/kg diet) from the 1st day to the 21st day,but were fed a semi-purified diet (12.50 mg of Fe/kg diet) after 21 days to deplete the body Fe stores.On the 28th day,after an overnight fast,all the birds were randomly allotted to four different Fe sources [FeSO_4,Fe-Gly (II),FeCl_3 and Fe-Gly (Ⅲ)].Three points five mL nutrient solution was injected to a broiler's duodenum by technology of in situ ligated intestinal loops and a perfusion group without Fe sources added to the media was designed to exclude the effect of endogenous Fe.Being incubated for 30 min,duodenal midpieces sections were collected for analyses by μ-XRF and μ-XANES techniques.It was found that Fe concentration for ferrous Fe sources [FeSO_4 and Fe-Gly (Ⅱ)] was significantly higher than that for ferric Fe sources [FeCl_3 and Fe-Gly (Ⅲ)] in the duodenal wall,moreover,Fe-Gly (Ⅱ) group samples had the largest amount of Fe.μ-XANES spectra of Fe for the four sources were basically the same in the duodenal wall,which indicated that despite the ferric iron supplied to duodenum,ferrous iron could also be absorbed into the duodenal wall.