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1.
Corn milling byproducts are expected to increase dramatically in supply as the ethanol industry expands. Distillers grains, corn gluten feed, or a combination of both byproducts offer many feeding options when included in feedlot rations. These byproduct feeds may effectively improve cattle performance and operation profitability. When these byproducts are fed in feedlot diets, adjustments to grain processing method and roughage level may improve cattle performance. Innovative storage methods for wet byproducts and the use of dried byproducts offer small operations flexibility when using byproducts. As new byproducts are developed by ethanol plants, they should be evaluated with performance data to determine their product-specific feeding values.  相似文献   
2.
Within the sensitive soils of the River Oder Basin (E Brandenburg, Germany), chloride‐tracer transport was studied with respect to soil‐surface conditions of the well structured clayey topsoil (disturbed vs. undisturbed) and irrigation mode (flooding vs. sprinkling). The spatial variation of chloride and dye distribution was sampled in a regular grid within different soil depths. Different methods were used for the analysis of spatial heterogeneity: a heterogeneity index HI derived from fitting parameters of the cumulative distribution function, semivariogram analyses to identify the spatial representativity of observations and to classify the spatial variation, and Spearman's rank correlations to examine the spatial similarity of tracer distribution across different soil depths. Soil aggregation was obvious throughout the soil profile, and macropores and fractures were preferred flow paths for the tracer. Flood irrigation resulted in more “uniform” distribution than sprinkling did. However, preferential flow was identified for all treatments, where, once established below the surface layer, flow paths led to heterogeneity indices manifesting nonuniform flow and reduced lateral mixing between macropores and soil matrix. Within the flooded plot, spatial structure of chloride concentration was moderate unlike the strongly structured variation within the sprinkled plots. For purposes to generalize and to assess regional risk of the water and solute transport within the topsoil of the River Oder Basin, spatial autocorrelation ranges of about 15 cm should be considered and included into concepts of soil protection and land‐use management, soil‐sampling strategies, or modeling approaches.  相似文献   
3.
Mammals developed an immune system able to functionally polarize into so-called type 1 or type 2 immune pathways, to resolve infections with intracellular and extracellular pathogens, respectively. In the well-studied avian immune system of the chicken, however, no evidence for polarized immunity could be found, as yet. To investigate whether these two major arms of mammalian immunity, regulated by a T helper (Th)1/Th2 cytokine balance, evolved similarly in birds, chickens were exposed to a prevalent intracellular (viral) or extracellular (helminth) infection. By using semi-quantitative RT-PCR analysis we provide evidence that polarization of Th1/Th2 type immunity extends beyond mammalian species, and, therefore, has been evolutionary conserved for more than 300 million years, when the lineages of mammalian and avian vertebrates are assumed to have segregated.  相似文献   
4.
The soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is a major pest of soybeans (Glycine max L. Merrill) in the central and southern United States. Soybean cyst nematode causes stunted top growth, root pruning and symptoms of mineral element deficiency in soybeans. The objective of this study was to determine the effect of two selections of SCN (I selected on PI209332 and IV selected on PI 89772) on macronutrient uptake, translocation, and tissue concentrations of soybean and to determine the elemental composition of cysts isolated from roots. Soybeans were grown in plastic tubes in the greenhouse where the middle one‐third of the Hodge fine sand (Typic Udipsamment) contained 0, 25,000, or 50,000 SCN eggs. After 35 days, plants were harvested and tissue nutrient element concentrations were determined. Plants infested with both SCN selections were smaller and had much less root volume than controls. Dry weight of each plant tissue decreased as SCN population was increased. Root concentration of potassium (K) and magnesium (Mg) was decreased, whereas root calcium (Ca) and phosphorus (P) concentrations were increased with SCN treatments. Leaf Mg and Ca concentrations increased with SCN treatment. Magnesium uptake per unit root volume was decreased, but Mg translocation (% of total plant content in aerial portion) was increased with SCN treatment. Calcium uptake per unit of root volume was increased, but translocation was unchanged by SCN treatment. The Ca and P concentration of cysts isolated from the soybean roots was high. This high concentration of Ca in cysts is interesting based on the greater root Ca concentration and uptake per unit of root volume in SCN infested plants. Since total uptake and root concentrations of both K and Mg were decreased by SCN treatment, infested soybeans might require very high levels of K and Mg fertilization. These results indicate that K and Mg fertility should be followed closely in SCM‐infested soybean fields.  相似文献   
5.
To assist our Kansas breeding program, we have developed nondestructive methods to test new lines of wheat for resistance to premature germination. The high sensitivity of subsurface imaging, compared with visual detection, α-amylase determination, or viscosity testing, permits germination detection at early stages. This report is concerned with detection reliability via chemical imaging of intact wheat kernels at early stages of germination by using an InGaAs focal plane detector array in the 1100–1700 nm range. Ninety kernels from each of six different cultivars, including HRW and HWW wheat, were exposed to moist conditions for 6, 12, 24, 36, and 48 h. Images of each 90 kernel group were examined, and images of those kernels exposed to moisture for 36 h were compared with images of kernels treated for 3 h as a control. Images of each were classified as sprouted or unsprouted. Criteria for classification included images of log 1/R at select wavelengths or images of select factors resulting from principle component analysis (PCA) treatment of reflectance intensity data from each pixel. Sprouted kernels determined by PCA factors 1 and 4 from 90 kernels tested in a 36-h moisture exposure numbered 87, 85, 80, 74, 70, 48 for six cultivars tested. Cultivar KS-2174 was shown to be distinctly more resistant to germination than the other cultivars. When KS-2174 was compared with Betty wheat, for all exposure times, Betty had approximately 45% more germinated kernels.  相似文献   
6.
We measured the lateral distribution of Br in a well-structured soil (clayey, kaolinitic, thermic Typic Kanhapludults) over a period of 40 days following a leaching event with Br-tagged water (Event-1) and the subsequent vertical transport of solute that occurred following a second leaching event (Event-2). The objectives were to determine the time required for solutes to become uniformly distributed laterally after Event-1, and the effect that degree of spatial distribution had on the subsequent vertical movement induced by Event-2. Six field plots, 1.2 by 1.2 m, were exposed to Event-1. Three of the plots were sampled 1, 5, or 40 days later. The three remaining plots were exposed to Event-2 either 1, 5, or 40 days following Event-1 and they were sampled the day following Event-2. A total of 319 samples were taken from a 38.5 by 38.5 cm area in the center of each plot at each of five depths ranging from 5 to 60 cm. Bromide was practically uniformly distributed in the surface layer immediately following Event-1, as indicated by a coefficient of variation (CV) of 25% among the 319 samples, but became progressively more non-uniformly distributed as depth increased. At 60 cm, the CV had increased to 240%. The longer we delayed sampling following Event-1, the more uniform was the lateral distribution of Br. During the 40 days following Event-1, Br became practically uniformly distributed across all layers, and the center of mass moved from 8 to 16 cm below the surface. Event-2 caused Br to move deeper within the soil profile when it occurred the day following Event-1 than when it occurred later, but because drainage occurred during the 40-day delay, the center of Br mass was located 26–27 cm below the surface after Event-2 regardless of the delay time.  相似文献   
7.
8.
Alfalfa plants, Moapa variety, were grown in nutrient solution containing isopropylring-[14C] carbanilate (43.8 μCi/liter propham). After 8 days, 41.2% of the radioactivity initially added to the nutrient culture was recovered; 10.9% of this was from shoots, 3.4% from roots and 26.9% from nutrient medium. Nonextracted residues accounted for 23% of the radioactivity in shoots and 62% of that in roots. The parent herbicide constituted 53 and 38% of the radioactivity extracted from shoots and roots, respectively. The balance of extracted 14C was polar metabolites which were purified and subjected to enzymatic and acid hydrolysis. Four aglycones were isolated, three of which were purified by thin-layer chromatography and characterized by mass spectrometry. The principal aglycones were: isopropyl-2-hydroxycarbanilate, isopropyl-4-hydroxycarbanilate, and 1-hydroxy-2-propylcarbanilate. The fourth aglycone was not identified.  相似文献   
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10.
The objective of this study was to evaluate protein composition and its effects on flour quality and physical dough test parameters using waxy wheat near‐isogenic lines. Partial waxy (single and double nulls) and waxy (null at all three waxy loci, Wx‐A1, Wx‐B1, and Wx‐D1) lines of N11 set (bread wheat) and Svevo (durum) were investigated. For protein composition, waxy wheats in this study had relatively lower albumins‐globulins than the hard winter wheat control. In the bread wheats (N11), dough strength as measured by mixograph peak dough development time (MDDT) (r = 0.75) and maximum resistance (Rmax) (r = 0.70) was significantly correlated with unextractable polymeric protein (UPP), whereas in durum wheats, moderate correlation was observed (r = 0.73 and 0.59, respectively). This may be due to the presence of high molecular weight glutenin subunits (HMW‐GS) Dx2+Dy12 at the Glu‐D1 locus instead of Dx5+Dy10, which are associated with dough strength. Significant correlation of initial loaf volume (ILV) to flour polymeric protein (FPP) (r = 0.75) and flour protein (FP) (r = 0.63) was found in bread wheats, whereas in durum wheats, a weak correlation of ILV was observed with FP (r = 0.09) and FPP (r =0.51). Significant correlation of ILV with FPP in bread wheats and with % polymeric protein (PPP) (r = 0.75) in durum lines indicates that this aspect of end‐use functionality is influenced by FPP and PPP, respectively, in these waxy wheat lines. High ILV was observed with 100% waxy wheat flour alone and was not affected by 50% blending with bread wheat flour. However, dark color and poor crumb structure was observed with 100% waxy flour, which was unacceptable to consumers. As the amylopectin content of the starch increases, loaf expansion increases but the crumb structure becomes increasingly unstable and collapses.  相似文献   
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