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71.
Elke Bloem Silvia Haneklaus Ewald Schnug 《Journal of the science of food and agriculture》2007,87(8):1576-1585
Under natural conditions, the content of the bioactive compound glucotropaeolin in the vegetative tissue of Tropaeolum majus is too low to be used directly for the preparation of a mono‐drug. In the present study the influence of sulfur and nitrogen fertilization and the post‐harvest drying procedure on the glucotropaeolin content was evaluated in order to minimize losses of the active glucosinolate. In 2001, field experiments with three levels of nitrogen and sulfur fertilization were conducted on two different sites. Nitrogen fertilization had no consistent influence on the glucotropaeolin content while sulfur fertilization with 100 kg S ha?1 enhanced the glucotropaeolin content in leaves and seeds significantly by factors of 1.4–2.1 and 1.6–1.8, respectively. The results of the post‐harvest treatment showed that a gentle drying procedure at 40°C in a ventilated oven induced an increase in the glucotropaeolin content in leaves of 1.4–3.2‐fold (from 10.7–25.5 to 30.9–44.6 µmol g?1 dry weight) compared to sampling in liquid nitrogen followed by freeze‐drying of the samples. This paper delivers new insights into glucosinolate metabolism that will contribute significantly not only to warrant a high content of bioactive compounds in medicinal plants, but also to promote glucosinolate concentrations in various crops by appropriate post‐harvest treatments. Copyright © 2007 Society of Chemical Industry 相似文献
72.
The pig genetics of Duroc, Pietrain (MHS homozygote negative, PiNN), Pietrain (MHS homozygote positive, PiPP) and a F2-Duroc-Pietrain cross-breed were analyzed. The animals had comparable (P > 0.05) carcass weights, but the PiPP pigs had higher carcass yield and lean meat values (P < 0.05). Considering the meat quality characteristics, the PiPP showed a faster pH drop and higher electrical conductivity, drip loss, shear force as well as lightness and redness values (P < 0.05). The PiPP animals had less slow-twitch-oxidative (STO) and more fast-twitch-glycolytic (FTG) muscle fibers, whereas the results of the Duroc animals were converse (P < 0.05). The STO and FTG fibers of the PiPP animals were larger than those of the other genetics (P < 0.05). The analysis of the mitochondrial respiratory activity (MRA) using permeabilized longissimus muscle fibers resulted in no differences between the pig genetics before and immediately after slaughter. During chilling the MRA decreased in all pigs but to a higher extent in the PiPP pigs (P < 0.05). 相似文献
73.
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75.
Soyeon Bae Bjoern Reineking Michael Ewald Joerg Mueller 《International journal of remote sensing》2013,34(17):6469-6489
Light detection and ranging (lidar) is a useful tool for measuring three-dimensional habitat structure; hence, its use in habitat suitability models has been explored, both as a single resource and in combination with other remote-sensing techniques. Here, we evaluated the suitability of airborne lidar data in comparison with aerial photographs and field surveys for modelling the distribution of an endangered and cryptic forest species, the hazel grouse (Bonasa bonasia). The study was conducted in the Bavarian Forest National Park of southeast Germany. Subsequently, a prediction map for conservation planning was generated for a large area, which encompassed the National Park. We examined the utility of lidar data for generating a hazel grouse distribution model by using machine learning (boosted regression trees), and then compared the results to variables derived from field surveys and aerial photographs, both separately and in combination. The cross-validated discrimination ability of the model was slightly higher when using lidar data (area under the receiver operator characteristic curve (AUC), 0.79) compared to models using aerial photographs (AUC, 0.75) or field survey data (AUC, 0.78). The predictive performance consistently increased when combining the predictors from different sources, with an AUC of 0.86 being produced in the model combining all three data sources. The three data sources complemented one another, with each data source probably having an advantage at deriving one of three key aspects of the hazel grouse habitat, namely, vertically well-structured forest stands, horizontally mixed successional vegetation stages, and certain deciduous trees as food resources such as mountain ash (Sorbus aucuparia). In addition, the diverse lidar metrics might be applied to simultaneously characterize vertically and horizontally well-structured forest stands. We conclude that public available airborne lidar data are a viable source for creating habitat suitability maps for large areas and may have increased utility for detecting forest characteristics and valuable wildlife habitats. 相似文献
76.
Sebastian Martin Peter Kaufmann Mario Botsch Martin Wicke Markus Gross 《Computer Graphics Forum》2008,27(5):1521-1529
Finite element simulations in computer graphics are typically based on tetrahedral or hexahedral elements, which enables simple and efficient implementations, but in turn requires complicated remeshing in case of topological changes or adaptive refinement. We propose a flexible finite element method for arbitrary polyhedral elements, thereby effectively avoiding the need for remeshing. Our polyhedral finite elements are based on harmonic basis functions, which satisfy all necessary conditions for FEM simulations and seamlessly generalize both linear tetrahedral and trilinear hexahedral elements. We discretize harmonic basis functions using the method of fundamental solutions, which enables their flexible computation and efficient evaluation. The versatility of our approach is demonstrated on cutting and adaptive refinement within a simulation framework for corotated linear elasticity. 相似文献
77.
Effect of water activity on growth and enterotoxin D production of Staphylococcus aureus 总被引:1,自引:0,他引:1
Four enterotoxin D-producing strains of Staphylococcus aureus, were cultured at 37 degrees C in brain heart infusion broth adjusted to various water activity (aw) levels by means of NaCl. For high cell inocula growth of all strains and enterotoxin D production were observed within 6 days at aw levels down to 0.86. 相似文献
78.
Can calcium chloride injection facilitate the ageing-derived improvement in the quality of meat from culled dairy cows? 总被引:1,自引:0,他引:1
This study investigated whether the positive effects of ageing on tenderness of meat from culled dairy cows can be facilitated by CaCl2. Injections of 250 mM CaCl2 solution (10% wt/wt) were performed on Longissimus dorsi samples from 32 7-yrs old cows. Samples were vacuum packaged and aged for 0, 1, 3, 5 and 7 days. Ageing alone produced lighter and less red meat with lower shear force, higher myofibrillar fragmentation and tenderness scores but also elevated lipid oxidation. For most traits investigated, CaCl2-injected meat exhibited similar ageing effects, but drip loss increased with age. The CaCl2-injected meat had a lower shear force and myofibrillar fragmentation increased more rapidly, but drip loss, off-flavour scores, colour stability and oxidative stability were inferior to untreated meat. Overall, it was found possible to accelerate tenderisation of such meat with CaCl2, but only at the cost of adverse effects in some other quality traits. 相似文献
79.
Sustainable bioenergy systems are, by definition, embedded in social, economic, and environmental contexts and depend on support of many stakeholders with different perspectives. The resulting complexity constitutes a major barrier to the implementation of bioenergy projects. The goal of this paper is to evaluate the potential of Multi Criteria Analysis (MCA) to facilitate the design and implementation of sustainable bioenergy projects. Four MCA tools (Super Decisions, DecideIT, Decision Lab, NAIADE) are reviewed for their suitability to assess sustainability of bioenergy systems with a special focus on multi-stakeholder inclusion. The MCA tools are applied using data from a multi-stakeholder bioenergy case study in Uganda. Although contributing to only a part of a comprehensive decision process, MCA can assist in overcoming implementation barriers by (i) structuring the problem, (ii) assisting in the identification of the least robust and/or most uncertain components in bioenergy systems and (iii) integrating stakeholders into the decision process. Applying the four MCA tools to a Ugandan case study resulted in a large variability in outcomes. However, social criteria were consistently identified by all tools as being decisive in making a bioelectricity project viable. 相似文献
80.
Andreas Pichler Sandra Traint Thomas Hebesberger Peter Stiaszny Ewald A. Werner 《国际钢铁研究》2007,78(3):216-223
Despite the extensive research and development work done in the field of high strength thin sheet multiphase steel grades, in the past, there are still two main challenges to be tackled, particularly for steel grades with tensile strength levels above 780 MPa. First a challenging optimisation and improvement of the overall processing in the steel plant is still necessary. This includes modified and improved layouts of processing lines. Further, due to the limited application and lacking feedback an overall customer oriented development and optimization is still necessary. Therefore, in a first step, this work reports on the alloy concepts and phase transformations in the annealing lines required for the adjustment of the microstructure of DP and TRIP grades. Then, the most critical processing steps are mentioned and in particular the demanded processing parameters in the annealing lines and the resulting layouts are highlighted. In a further part, three selected items of a costumer oriented development and optimisation of DP and TRIP steel grades are discussed. These include the improvement of the flange‐ability and bendability and efforts oriented towards the reduction of the banded structure in DP and TRIP steel grades. Finally, the improvement of the fracture appearance of spot welded joints of TRIP steels is highlighted and alloy concepts with a balance between weldability and formability are introduced. 相似文献