Effect of Glass Transition and Cross‐Linking on Rheological Properties of Gluten: Development of a Preliminary State Diagram

The glass transition temperature of gluten at different moisture levels was determined by differential scanning calorimetry and mechanical spectrometry. The dynamic moduli (G′ and G″) of gluten with 10–40% moisture were measured as a function of temperature by pressure rheometry. At 10% moisture, gluten exhibited entangled polymer flow at 92–140°C and networking reactions at higher temperatures. At higher moisture levels, gluten experienced structured flow before networking cross‐linking reactions. The onset temperature of the reaction zone was 120°C in 20% moisture gluten and 93°C at moisture levels of 30–40%. Softening of the vitrified network occurred at 184, 181, and 170°C in 20, 30, and 40% moisture gluten, respectively. A preliminary state diagram of gluten as a function of moisture and temperature was developed.     

舍饲肉牛最大收益与精料消耗最省的饲料配方模型与计算

应用优化理论研究了肉牛生产系统的最大收益饲料配方问题,并根据我国北方农区舍饲育肥牛的实际,建立了肉牛最大收益饲料配方模型。讨论了肉牛最大收益饲料配方模型的目标函数、约束条件、粗饲料约束因子以及计算输出,并建立了计算软件进行了实际计算。应用我国北方农区肉牛饲料原料,通过最大收益饲料配方模型,给出了计算结果。还讨论并给出了肉牛精料消耗最省的饲料配方模型及其计算。     

Factors affecting soil loss at plot scale and sediment yield at catchment scale in a tropical volcanic agroforestry landscape

Tropical deforestation and land use change is often perceived as the major cause of soil loss by water erosion and of sediment load in rivers that has a negative impact on the functioning of hydropower storage reservoirs. The Sumberjaya area in Sumatra, Indonesia is representative for conflicts and evictions arising from this perception. The purpose of this study as part of a Negotiation Support System approach was to assess sediment yield both at plot and catchment scale and to relate it to a variety of possible clarifying factors i.e. land use, geology, soil and topography. Sediment yield at catchment scale per unit area, was found to be 3–10 times higher than soil loss measured in erosion plots. A stepwise regression showed that the dominant factors explaining sediment yield differences at catchment scale in this volcanic landscape were a particular lithology (Old Andesites) and slope angle followed by the silt fraction of the top soil. In lithologically sensitive areas soil loss at the plot scale under monoculture coffee gardens decreases over time from on average 7–11 Mg ha^? 1 yr^? 1 to 4–6 Mg ha^? 1 yr^? 1, mainly because of the development of surface litter layers as filters and top soil compaction in the areas without litter, but remains higher than under shade coffee systems or forest. The runoff coefficient under monoculture coffee remains on average significantly higher (10–15%) than under forest (4%) or under shade coffee systems (4–7%). In lithologically stable areas soil loss remained below 1.8 Mg ha^? 1 yr^? 1 and the runoff coefficient below 2.5% under all land use types, even bare soil plots or monoculture coffee gardens. Less than 20% of the catchment area produces almost 60% of the sediment yield. The reduction of negative off-site effects on e.g. the life time of a storage reservoir would benefit greatly from an improved assessment of the lithologies in volcanic landscapes and the consideration of potential sediment source and sink areas. In lithologically sensitive areas, a shift from sun to shade coffee systems may result in reducing surface runoff and soil loss, although water erosion at the plot scale is not the main contributor to sediment yield at the catchment scale. The quantification of land use effects on dominant erosive processes such as river bank and river bed erosion, landslides and the concentrated flow erosion on footpaths and roads can contribute to more targeted efforts and relevant incentives to reduce (or live with) sediment load of the rivers.     

Winter wheat (Triticum aestivum L.) growth potential in the Slovak rural landscape

By the application of geographic information system (GIS) based on existing databases on soil characteristics, it is possible to quantify and assess categories of soil suitability important for crop cultivation. In this article we demonstrate such methods for winter wheat. The objective was to differentiate the Slovak rural landscape with respect to the possibility of effective winter wheat cultivation. The differentiation was based on soil climatic and production economic parameters. For soil categorization, correlation relationships between the site properties (soil and climatic conditions) and crop biological and agro-technical requirements were considered. The prediction was subsequently interpolated into four suitability categories: soils not suitable for wheat cultivation, less suitable soils, suitable soils, and very suitable soils. The database was developed and each area was added to it as well as the particular category of suitability for wheat cultivation. By using the GIS distribution in Slovakia, the maps of soil suitability categories for wheat cultivation were generated. In Slovakia, 29% of farmland was found to be very suitable for wheat cultivation, 25% suitable, 9% less suitable and 37% non-suitable by our calculations. These categories are characterized in detail and specified from the point of view of geographic, soil, climatic, production, economic and energetic parameters.     

Larval and adult food preferences of the poinsettia thrips <Emphasis Type="Italic">Echinothrips americanus</Emphasis> Morgan, 1913 (Thysanoptera: Thripidae)

Numerous occurrence of Echinothrips americanus Morgan, 1913, a relatively newly established pest in European greenhouses, on a wide spectrum of cultivated plants throughout Slovakia has encouraged us to present current data on its food ecology. Analysing 1,650 plant species, the poinsettia thrips was found on 106 species (48 families) including 19 showing sporadic, 75 moderate and 17 high infestation. Larvae were detected on 25 plant taxa from 13 families, most of them being new hosts. Mature clusters of Acalypha hispida, showing moderate to high infestation level and carrying both larvae and adults, were selected for more detailed statistical evaluation. Preference of adults for upper and lower leaf surface tends to be without statistical significance, the larvae on the contrary were strongly related to the lower side (Pearson’s χ² = 13.3552, P = 0.0013). Concerning the age, increased occurrence was apparent on younger leaves for both larvae and adults. For larvae the nonparametric test gives the statistical difference between three age categories of leaves with the following values: Kruskal–Wallis χ² = 6.6384, P = 0.03618. The statistical significance of age seems to be more crucial for younger shoots, as proved by the statistics for both larvae (Kruskal–Wallis χ² = 8.4852, P = 0.0144) and adults (Kruskal–Wallis χ² = 7.1049, P = 0.0287). Different food preferences of larvae and adults may result in specific approach when applying an effective biological or chemical control. Narrower tolerance of larvae could make them more manageable target in plant protection instead of efforts to control the whole thrips population.     

The effects of the stress of long-term physical and psychological training on the red blood cell picture in dogs

The effect of the physical and psychical load of long-continued training on the components of the red blood picture was studied in thirty clinically healthy dogs of two age categories. The values of erythrocytes were found to be increased whereas those of haemoglobin, haematocrit and other components (MCV, MCH, BI, MCHC) were depressed. The effects are discussed of training, adaptation process, parasympathicotonic form of overload, and qualitative nutrition deficiency as a reflection of the studied training load as exerted on certain insufficiency of the desired formation of the red blood picture, and thereby of a possible adverse impact on the performance of the trained dog.     

东方对虾饲料不同蛋白源的比较

本试验以鱼粉(F),豆饼(S)和棉籽饼(C)作为东方对虾饲料的主要蛋白源。为适应实际生产的需要,还设计了以混合蛋白源(M)组成的饲料。每种蛋白源的饲料设计了两个粗蛋白水平:前期46%和后期44%。用8种饲料(M-46,F-46,S-46,C-46,M-44,F-44,S-44和C-44)饲喂初重为6.1 g 的东方对虾,观察不同蛋白源对试验对虾的成活率、生长性能和饲料转化率的影响。本试验还以 Cr_2O_3为指示剂,测定东方对虾对不同蛋白源的粗蛋白和主要氨基酸的消化率。为期42 d 的试验结果表明,不同蛋白源对所观察指标有显著影响。     

Selected biochemical values of clinically healthy dogs

Twenty-six parameters of clinical biochemical properties were determined in 72 clinically healthy German Shepherd dogs. The standard values were determined for total protein, protein spectrum, albuminoglobulin quotient, enzymic activities for AST, ALT, LD, LD-1, and ALP, for sodium, potassium, magnesium, calcium, inorganic phosphorus, and chlorides, complete prameters of the acid-base balance of the blood, and the values of glucose, urea, lactic acid, and creatinin. For determining these standards, dogs were selected at the age of 6.5 months to 7 years. All the statistically processed results are obtained from a number of animals which would secure 95% reliability and accuracy of the results, which would allow for sufficient generalization. Differences concerning the influence of age were not demonstrated in any of the determined biochemical values. The results are regarded as representative standards which can be used for clinical and laboratory diagnostics and prognostics in veterinary cynology and for clinical physiology of the German Shepherd dog breed.     

Associations between anti-Fasciola hepatica antibody levels in bulk-tank milk samples and production parameters in dairy herds

Our primary objective was to determine the relationships between Fasciola-specific antibody levels in bulk-tank milk and measures of productivity to estimate economic losses that are associated with Fasciola infections. A bulk-tank milk sample was collected in March 2004 from 1105 dairy herds in Flanders and the antibody levels against Fasciola hepatica (ODRf) and Ostertagia ostertagi (ODRo) were determined. The association of ODRf with four production parameters (milk yield, milk-protein %, milk-fat % and inter-calving interval) was assessed by multivariable linear-regression models. Production data were available for 463 out of the 1105 herds sampled. An increase in ODRf from the 25% quantile (0.428) to the 75% quantile (1.064) was associated with a decrease in the annual average milk yield of 0.7kg/(cowday) (P=0.002), with a decrease in the average milk-fat % of 0.06% (P<0.001) and with an increase of the mean inter-calving interval of 4.7 days (P=0.03). No significant relationship was found with the average milk-protein %. When the relationships of ODRf and ODRo with milk yield were tested simultaneously, we saw an additive rather than synergistic effect of concurrent infections.