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71.
The synthesis of N-arylamidines and N-arylimidates of substituted acetic acids is described. Those amidines and imidates possessing a phosphorus ester as substituent showed insecticidal and high acaricidal properties. By contrast, their precursors were ineffective. 相似文献
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73.
Zusammenfassung Birnengitterrost breitet sich in nicht kommerziell genutzten Anlagen zunehmend aus, vor allem dort, wo Pflanzenschutzmaßnahmen unterbleiben. In unserer Untersuchung wurde nach alternativen Lösungen gesucht, den Befall zu minimieren. Dazu wurden Pyrus-Arten und -Hybriden ohne Pflanzenschutz angezogen und der natürliche Befall bewertet. Die Arten Pyrus korzhinskyi, P. betulifolia, P. cordata und die Hybride P. salicifolia Pendula zeigten den geringsten Befall. Sie könnten als Züchtungsausgangsmaterial eingesetzt werden. Ebenso scheint eine Prüfung als Park- oder Landschaftsgehölz sinnvoll. 相似文献
74.
Wittek T Fürll M Constable PD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(4):574-580
Left displaced abomasum (LDA) and abomasal volvulus (AV) occur most commonly in postparturient dairy cows. Our main hypothesis was that endotoxemia occurred more frequently in the peripheral blood of cows with LDA or AV than in healthy cows because increased luminal pressure in AV or LDA, or the presence of a hemorrhagic strangulating obstruction in AV, may have injured the abomasal mucosa, thereby facilitating translocation of luminal endotoxin into the circulation. Therefore, our main objective was to compare the prevalence and magnitude of endotoxemia in healthy postparturient cows with the prevalence and magnitude of endotoxemia in cows with AV and LDA. We examined 60 adult dairy cows in early lactation that were diagnosed with AV (n = 15) or LDA (n = 15) or were healthy on physical examination (control group, n = 30). Jugular venous blood was obtained from cows in all 3 groups, and right gastroepiploic venous blood was obtained during surgical correction of AV and LDA immediately after repositioning of the abomasum. Platelet-rich plasma endotoxin concentrations were measured with a chromogenic limulus amoebocyte lysate assay. Endotoxin was detected in jugular vein plasma in 50% (15/30) of control cows; however, the prevalence of endotoxemia was significantly lower (P < .05) in cows with AV (7%, 1/15) or LDA (20%, 3/15). Endotoxin was detected simultaneously in right gastroepiploic and jugular vein plasma in only 1 cow with LDA and 0 cows with AV. Contrary to our hypothesis, we conclude that endotoxemia is infrequently present in postparturient dairy cows with AV or LDA. 相似文献
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Past,current and future drivers for the development of decision support systems in forest management
The potential for development in decision support for forest management is set by decision theory, available technology and methods. Demands for decision support are emerging from contemporary challenges and problems of forest management which act as stimuli for the science community. Objectives and approaches in forest management as well as technologies have been changing throughout history. Accordingly, the demand for tools to support planning and decision-making has evolved. In this contribution, the authors review the historic development of decision support systems (DSS) for forest management and discuss past, current and future drivers. Based on evidence from scientific literature, case studies in the frame of the Forest Management Decision Support Systems (FORSYS) action, as well as experiences of the authors some hypotheses about the future of DSS are drawn. It is shown that in the past, the drivers evolving from forest management as well as decision support technologies have influenced the way of how models and methods have been applied as well as how DSS architectures have been designed. It is concluded that in the future, the challenges for DSS development will increase, as the complexity of decision-making processes and the related models will compete with the user demands which ask for simplicity. 相似文献
77.
Fleitmann D Burns SJ Mudelsee M Neff U Kramers J Mangini A Matter A 《Science (New York, N.Y.)》2003,300(5626):1737-1739
A high-resolution oxygen-isotope record from a thorium-uranium-dated stalagmite from southern Oman reflects variations in the amount of monsoon precipitation for the periods from 10.3 to 2.7 and 1.4 to 0.4 thousand years before the present (ky B.P.). Between 10.3 and 8 ky B.P., decadal to centennial variations in monsoon precipitation are in phase with temperature fluctuations recorded in Greenland ice cores, indicating that early Holocene monsoon intensity is largely controlled by glacial boundary conditions. After approximately 8 ky B.P., monsoon precipitation decreases gradually in response to changing Northern Hemisphere summer solar insolation, with decadal to multidecadal variations in monsoon precipitation being linked to solar activity. 相似文献
78.
Lisa A. Weber Christina Puff Jutta Kalbitz Manfred Kietzmann Karsten Feige Konstanze Bosse Karl Rohn Jessika‐M. V. Cavalleri 《Journal of veterinary pharmacology and therapeutics》2021,44(1):47-57
The naturally occurring betulinic acid (BA) and its derivative NVX‐207 show anticancer effects against equine malignant melanoma (EMM) cells and a potent permeation in isolated equine skin in vitro. The aim of the study was to determine the in vivo concentration profiles of BA and NVX‐207 in equine skin and assess the compounds’ local and systemic tolerability with the intent of developing a topical therapy against EMM. Eight horses were treated percutaneously in a crossover design with 1% BA, 1% NVX‐207 or a placebo in a respective vehicle twice a day for seven consecutive days with a seven‐day washout period between each formulation. Horses were treated at the neck and underneath the tail. Concentration profiles of the compounds were assessed by high‐performance liquid chromatography in the cervical skin. Clinical and histopathological examinations and blood analyses were performed. Higher concentrations of NVX‐207 were found in the skin compared to BA. Good systemic tolerability and only mild local adverse effects were observed in all three groups. This study substantiates the topical application of BA and NVX‐207 in further clinical trials with horses suffering from EMM; however, penetration and permeation of the compounds may be altered in skin affected by tumors. 相似文献
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80.
Stefan Gth Helmut Meuser Carl-Andreas Abitz Gerd Wessolek Manfred Renger 《植物养料与土壤学杂志》1989,152(2):143-149
Potassium (K) delivery to the roots of cereal plants in soils is determined by both soil and plant factors, root growth and root length density in particular, being of major importance. In Part A of this paper an evaluative framework is shown for sandy and loamy-silty soils for determination of root length density based on available field capacity, soil depth in 10 cm steps and the climatic water balance. A good correlation (r2 = 0.86) was found when the root length densities were determined at ear emergence. With the help of correction functions root length densities can be subsequently estimated for the other phenological stages (stem elongation, flowering and yellow ripeness). The method described is suited for determining root length densities in water and nutrient transport simulation models. In Part B exchange resins were used to simulate the K delivery from the soil to the root. Measurements were made for different soils and water contents. The depletion zone near the exchange resin was 6 mm thick after 4 days. This corresponds to results obtained from root measurements. Comparisons between a sandy and a loamy-silty soil show, that K delivery by diffusion for equal concentrations depends primarily on soil moisture and pore tortuosity. This leads to the conclusion, that soil physical properties must be taken into consideration when evaluating chemical soil analysis and recommendating fertilizer applications. 相似文献