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排序方式: 共有160条查询结果,搜索用时 15 毫秒
1.
Azin Rekowski Monika A. Wimmer Bernd Hitzmann Bernhard Hermannseder Heike Hahn Christian Zrb 《植物养料与土壤学杂志》2020,183(2):260-270
Background: Nitrogen losses is an economic problem for wheat production and a high risk to the environment. Therefore, improved N fertilizer management is a key to increasing the N efficiency and minimizing N losses. To increase N efficiency, enhanced fertilizers such as urea combined with urease inhibitor can be used. Aims: The aim of present study was to evaluate the effects of different N forms on grain storage protein subunits in winter wheat and to examine whether the observed changes correlate with parameters of baking quality. Methods: The investigation was performed over two consecutive years at two locations in Germany. Protein subunits were analyzed by SDS‐PAGE. Results: Protein concentrations were similarly increased after fertilization with ammonium nitrate and urea + urease inhibitor. Analysis of the individual storage protein fractions indicated that both fertilizers specifically enhanced ω‐gliadins and HMW glutenins, but the effect was more pronounced in the ammonium nitrate treatment. Application of urea + urease inhibitor had greater influence on the protein composition and resulted in higher specific baking volume as well as the best fresh keeping ability, in comparison with urea treatment. Conclusion: Considering that the urea + urease inhibitor treatment resulted in almost comparable improvements of NUE and baking quality, with the additional benefit of reduced N losses in combination with easy handling, urea + urease inhibitor can be recommended as a viable alternative to both urea alone and ammonium nitrate treatments. This opens up an opportunity for the reduction of N loss in wheat production when use of urea is preferred. 相似文献
2.
Revisiting the Roles of the University in Regional Economic Development: A Triangulation of Data 下载免费PDF全文
Heike Mayer 《Growth and change》2017,48(4):787-804
There is a general understanding that university plays a crucial role in regional development under the current age of knowledge economy. At the same time, we have observed a fair number of counter‐evidentiary studies, demonstrating several regions that do not thrive despite strong research universities or other patterns of development in the absence of research universities. However, they are based on case studies of individual universities or regions, and the findings currently cannot be generalized. Another set of studies that have challenged the effect of universities at the nationwide scale and demonstrated its disproportionately small impact of universities, but their scope is limited to spin‐offs, patents, and license activities. In this article, we propose to investigate this subject more systematically by triangulating three methods: 1) national‐scale regression models with Business Dynamics Statistics and National Establishment Time Series data, 2) a regional survey of IT and life science firms in four so‐called “second tier regions,” and 3) a microeconomic firm‐level analysis based on interviews with founders of technology intensive firms. Furthermore, we test the roles of university beyond those explicit, direct measures of spin‐offs and patents by analyzing the firm formation rate and firm growth rate at the regional level, as well as the sources of growth at the company level. All results point in the same direction: The research function of the university has been overstated, and the teaching function of the university has been underappreciated. These findings provide profound implications for the policy of regional development. 相似文献
3.
Knueppel A Lange S Altmann S Sekora A Knuebel G Vogel H Lindner I Freund M Junghanss C 《Veterinary immunology and immunopathology》2012,145(1-2):233-240
Denileukin Diftitox (ONTAK®, DAB389 IL-2) is a recombinant DNA-derived fusion protein depleting cells that express high-affinity IL-2 receptor. Important cell targets are CD4+CD25+Foxp3+ regulatory T cells (Treg). Elimination of immunosuppressive Treg by Denileukin Diftitox may provide a way to modulate immune tolerance following stem cell transplantation. Here, we combined Treg depletion with a vaccination approach to induce donor-specific immune reactions. To investigate this approach we chose the mixed chimerism canine stem cell transplantation model which represents a high state of tolerance between two hematopoietic systems. The aim was therefore to induce a graft versus hematopoiesis effect thereby converting mixed to full donor chimerism. Dog leukocyte antigen identical siblings that had developed a stable mixed chimerism after non-myeloablative stem cell transplantation received a single dose of Denileukin Diftitox (18 μg/kg, i.v.) followed by several cell-lysate vaccinations. Host peripheral blood mononuclear cell lysates combined with CpG-ODN, and Montanide® ISA 51 were locally applied. In vitro studies demonstrated that canine Treg are a target of Denileukin Diftitox. The suppression of T-cell proliferation by Treg was abolished by addition of Denileukin Diftitox (10 nM). An increase of proliferation of median 300% (range: 200%–425%) was observed. No change in donor chimerism was observed after administration of Denileukin Diftitox and vaccination. This study highlights that application of Denileukin Diftitox resulted in a depletion of Treg followed by an increase of immune response in vitro. This effect could not be confirmed in vivo even if the immune system was stimulated by vaccinations. 相似文献
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The influence of transplanting on height, root neck diameter, and grading was investigated for Carpinus betulus, Quercus robur, and Euonymus europaeus on three sites with different climate and soil properties. Additionally, plant growth was characterized by the shoot-to-root ratio, height-to-root neck diameter, and proportions of coarse and fine roots. The significance of the growth parameters as criteria for survival is discussed. Transplanting influenced shoot growth more than root growth. The growth of the plants was highly site-dependent. Transplanting increased growth most on the site with the best conditions for water and N supply. Transplanting had no effect on grading for the site with the worst water supply. 相似文献
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Conraths FJ Köhler H Werner O Beer M Depner KR Geue L Kaden V Staubach C Pötzsch C Schares G Mettenleiter TC 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(9-10):354-364
The Friedrich-Loeffler-Institut, founded in 1910 by Friedrich Loeffler, the discoverer of the first animal virus, foot-and-mouth disease virus, is the oldest virological research facility in the world. Beyond viruses, its area of competence has significantly expanded since its foundation and now also covers bacterial, parasitic and prion diseases of livestock, poultry and aquatic animals. Presently located at four sites within Germany (Insel Riems, Jena,Tübingen,Wusterhausen) the tasks of the institute as delineated in the Animal Disease Act encompass research on infectious animal diseases including zoonoses, import/export examinations, epidemiological studies in case of outbreaks of notifiable animal diseases, acting as reference laboratory for notifiable animal diseases and nationwide quality management of diagnosis of notifiable animal diseases. It is obliged to publish and maintain up-to-date diagnostic regimes for notifiable animal diseases, and it publishes a yearly report on animal health in Germany. With the increasing importance of infectious diseases of animals, in particular those potentially harmful to man (zoonoses), the Friedrich-Loeffler-Institut will be moving into new facilities including laboratories and animal facilities up to the highest biosafety level at its main site Insel Riems on the occasion of its 100th anniversary. 相似文献
8.
Rendulic S Jagtap P Rosinus A Eppinger M Baar C Lanz C Keller H Lambert C Evans KJ Goesmann A Meyer F Sockett RE Schuster SC 《Science (New York, N.Y.)》2004,303(5658):689-692
Predatory bacteria remain molecularly enigmatic, despite their presence in many microbial communities. Here we report the complete genome of Bdellovibrio bacteriovorus HD100, a predatory Gram-negative bacterium that invades and consumes other Gram-negative bacteria. Its surprisingly large genome shows no evidence of recent gene transfer from its prey. A plethora of paralogous gene families coding for enzymes, such as hydrolases and transporters, are used throughout the life cycle of B. bacteriovorus for prey entry, prey killing, and the uptake of complex molecules. 相似文献
9.
Pakull Birte Eusemann Pascal Wojacki Janine Ahnert Diana Liesebach Heike 《European Journal of Forest Research》2021,140(6):1543-1557
European Journal of Forest Research - In Germany, Douglas fir (Pseudotsuga menziesii Franco) is seen as a valuable species for future cultivation in times of climate change. Local seed production... 相似文献
10.
Dissolved and colloidal phosphorus fluxes in forest ecosystems—an almost blind spot in ecosystem research 下载免费PDF全文
Roland Bol Dorit Julich Dominik Brödlin Jan Siemens Klaus Kaiser Michaela Anna Dippold Sandra Spielvogel Thomas Zilla Daniela Mewes Friedhelm von Blanckenburg Heike Puhlmann Stefan Holzmann Markus Weiler Wulf Amelung Friederike Lang Yakov Kuzyakov Karl‐Heinz Feger Nina Gottselig Erwin Klumpp Anna Missong Carola Winkelmann David Uhlig Jakob Sohrt Klaus von Wilpert Bei Wu Frank Hagedorn 《植物养料与土壤学杂志》2016,179(4):425-438
Understanding and quantification of phosphorus (P) fluxes are key requirements for predictions of future forest ecosystems changes as well as for transferring lessons learned from natural ecosystems to croplands and plantations. This review summarizes and evaluates the recent knowledge on mechanisms, magnitude, and relevance by which dissolved and colloidal inorganic and organic P forms can be translocated within or exported from forest ecosystems. Attention is paid to hydrological pathways of P losses at the soil profile and landscape scales, and the subsequent influence of P on aquatic ecosystems. New (unpublished) data from the German Priority Program 1685 “Ecosystem Nutrition: Forest Strategies for limited Phosphorus Resources” were added to provide up‐to‐date flux‐based information. Nitrogen (N) additions increase the release of water‐transportable P forms. Most P found in percolates and pore waters belongs to the so‐called dissolved organic P (DOP) fractions, rich in orthophosphate‐monoesters and also containing some orthophosphate‐diesters. Total solution P concentrations range from ca. 1 to 400 µg P L?1, with large variations among forest stands. Recent sophisticated analyses revealed that large portions of the DOP in forest stream water can comprise natural nanoparticles and fine colloids which under extreme conditions may account for 40–100% of the P losses. Their translocation within preferential flow passes may be rapid, mediated by storm events. The potential total P loss through leaching into subsoils and with streams was found to be less than 50 mg P m?2 a?1, suggesting effects on ecosystems at centennial to millennium scale. All current data are based on selected snapshots only. Quantitative measurements of P fluxes in temperate forest systems are nearly absent in the literature, probably due to main research focus on the C and N cycles. Therefore, we lack complete ecosystem‐based assessments of dissolved and colloidal P fluxes within and from temperate forest systems. 相似文献