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1.
Fortes Maira Salomão Lopes-Mori Fabiana Maria Ruiz Caldart Eloiza Teles Constantino Caroline Evers Fernanda Pagliari Sthefany de Almeida Jonatas Campos Barros Luiz Daniel Freire Roberta Lemos Garcia João Luis Headley Selwyn Arlington Navarro Italmar Teodorico 《Tropical animal health and production》2018,50(2):413-419
Tropical Animal Health and Production - This study investigated the prevalence of caprine toxoplasmosis in goat herds from Southern Brazil by the indirect immunofluorescence assay (IFA), and... 相似文献
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Moore DA Truscott ML St Clair L Klingborg DJ 《Journal of veterinary medical education》2007,34(2):112-121
Assuming leadership roles in veterinary student governance or club activities could be considered an added stressor for students because of the impact on time available for personal and academic activities. The study reported here evaluated the effects of participation in a leadership program and leadership activity across two classes of veterinary students on measures of stress, using the Derogatis Stress Profile (DSP), and on veterinary school academic performance, measured as annual grade-point average (GPA) over a three-year period. Program participants and their classmates completed the DSP three times across the first three years of veterinary school. On average, participating students reported self-declared stress levels that were higher and measured DSP stress levels that were lower than those of the general population. Students were more likely to assume elected or appointed leadership roles while in their first three years of the veterinary degree program if they participated in the optional leadership program and demonstrated lower stress in several dimensions. Some increased stress, as measured in some of the DSP stress dimensions, had a small but statistically significant influence on professional school GPA. The study determined that the most important predictors of students' cumulative GPA across the three-year period were the GPA from the last 45 credits of pre-veterinary coursework and their quantitative GRE scores. The results of the study indicate that neither participation in the leadership program nor taking on leadership roles within veterinary school appeared to influence veterinary school academic performance or to increase stress. 相似文献
4.
Sabine Augustin Jan Evers Hans-Peter Dietrich Johannes Eichhorn Thomas Haussmann Regina Icke Ansgar Isenberg Wolfgang Lux Monica Musio Hans Pretzsch Winfried Riek Thomas Rötzer Bernd Schultze Andreas Schulze Jörg Schröder Walter Seidling Nicole Wellbrock Klaus von Wilpert Barbara Wolff 《European Journal of Forest Research》2005,124(4):251-260
In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and
other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system
in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse
effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary
air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring
was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and
feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal
Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives
of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification
and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading
to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected
level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis
(crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative,
as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the
extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
相似文献
Sabine AugustinEmail: |
5.
A polymerase chain reaction (PCR)-based method was developed for the detection of phytoplasma in insect feeding medium (sucrose). A correlation was established between the transmissibility of Flavescence dorée phytoplasma in the experimental leafhopper vector Euscelidius variegatus and its detection by PCR in the insect feeding medium. However, phytoplasma were detected in the insects' bodies 3 weeks before they began to transmit. Hence, PCR assays of the sucrose medium reflected phytoplasma vectoring ability probably by detecting it in the insect saliva, whereas detection of phytoplasma in the insect's body did not identify it as a vector. The assay was applied to two field-collected leafhoppers suspected of being phytoplasma vectors in Israel (Orosius albicinctus and Anaceratagallia laevis). The presence of phytoplasma in the body of specimens of the latter species was assayed by PCR in 1999. Phytoplasmas were detected in insects' bodies throughout the year, with no specific seasonal pattern. In the saliva, however, no phytoplasma could be detected in the autumn. This seasonal pattern supported the validity of the feeding-medium tests and their correlation to the insect's ability to transmit phytoplasma. Transmission assays indicated, to our knowledge for the first time, that O. albicinctus and A. laevis are vectors of phytoplasma in Israel. A simple PCR-based assay is thus provided, circumventing the need for tedious biological assays and enabling epidemiological studies of phytoplasma transmissibility on a large scale. 相似文献
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F. H. Evers 《European Journal of Forest Research》1971,90(1):363-369
Zusammenfassung Im Frühjahr 1971 wurden in 50–70j?hrigen Fichtenbest?nden entlang der Bundesautobahn Stuttgart-Karlsruhe im Streckenabschnitt
Heimsheim umfangreichere Sch?den durch Auftausalze festgestellt. Nadelverf?rbungen und Ausf?lle ergaben sich nicht nur im
Spritzwasserbereich entlang der Bestandesr?nder, sondern auch bis zu 100 m ins Bestandesinnere, wenn salz-(NaCl-) haltige
Schmelzw?sser über natürliche oder künstlich angelegte Abflu\systeme in die Best?nde gelangten. Die gesch?digten Fichten wiesen
über 3‰ bis rund 7‰ Chlorid in den Nadeln auf. Bei den 70–100 m im Bestandesinnern stehenden B?umen konnten ebenfalls hohe
Cl-Konzentrationen in den Nadeln festgestellt werden, was darauf hinweist, da? die Sch?digung über den Wurzelbereich erfolgt
sein mu?te. Auch im Boden waren stark erh?hte NaCl-Konzentrationen festzustellen.
Gef?hrdet durch abflie?endes, salzhaltiges Schmelzwasser sind besonders Fichtenbest?nde auf feinlehmreichen und tonigen B?den
in Mulden-und leichten Hanglagen, auch an Hangfü?en steilerer Lagen. Die Bedrohung w?chst in submontanen und montanen Gebieten.
Aus der Baden-Württembergischen Forstlichen Versuchs- und Forschungsanstalt, Sektion Pflanzenern?hrung und Düngung 相似文献
Summary In spring of 1971, rather extensive injuries were noted in 50–70 year old Norway spruce stands along the Stuttgart-Karlsruhe-Autobahn near Heimsheim. These damages are attributed to the infiltration of rock salt. Discolouring of needles and destruction of the trees not only occured along the border of the stands within spraying range, but was also observed up to 100 meters inside the stands where melted snow and ice containing salt had reached the stands through natural or artifical drainage systems. Needles of the damaged spruces contained from over 3‰ to approximately 7‰ of chlorine. Since needles of trees at 70 to 100 meters inside the stands also contained high concentrations of chlorine it must be concluded that the damage has been inflicted through the root system. High concentrations of NaCl were also found in the soil. Melted snow and ice containing salt is particularly dangerous when draining into spruce stands on loamy or clayey soil in hollows or on slight slopes, as well as at the bottom of steeper slopes. Danger increases in mountains and submountains areas.
Aus der Baden-Württembergischen Forstlichen Versuchs- und Forschungsanstalt, Sektion Pflanzenern?hrung und Düngung 相似文献
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9.
Chang-Hua Fang Bruno Clair Joseph Gril Tancrède Alméras 《Wood Science and Technology》2007,41(8):659-671
Transverse drying shrinkage was measured at microscopic and mesoscopic levels in poplar wood characterised by an increasing
growth strain (GS), from normal to tension wood. Results show that: (a) the drying shrinkage, measured as a relative thickness
decrease, was significantly higher for G-layer (GL) than for the other layers (OL), GL shrinkage was not significantly correlated
with GS, and OL shrinkage was negatively correlated with GS. (b) In gelatinous fibre (G-fibre), lumen size increased during
drying and this increase was positively related with GS, but in normal wood fibre, lumen size decreased during drying. These
findings suggest that GL shrank outwards (i.e., its internal perimeter increases), so that its shrinkage weakly affected the
total cell shrinkage and the mesoscopic shrinkage was controlled by the OL shrinkage which shrank inwards (i.e., its external
perimeter decreases). (c) Measurements done on 7 × 7 mm2 thin sections evidenced a negative correlation between transverse
shrinkage and GS, significant in T direction but weak in R direction. These observations at both levels allow to discuss the
contribution of GL to the mesoscopic shrinkage of tension wood. 相似文献
10.
U. Ammer G. Einsele W. Arnold O. Klee R. Agerer G. Agster U. Babel J. Behringer W. Böcking F. -H. Evers W. Fleck H. Günzl K. -F. Hofmann H. Janz J. Körner I. Kottke V. Kracht A. Krebs K. Kunzweiler W. -D. Langbein H. -U. Moosmauer S. Müller E. Nickel S. Pfeiffer R. Rausch H. Schmidt-Witte O. Schwarz R. Stegmayer 《European Journal of Forest Research》1983,102(1):282-324
Ohne Zusammenfassung
(Prof. Agerer seit 1982 am Institut für Systematische Botanik, München).
(Weilimdorf)
(zuvor t?tig bei der FVA Stuttgart, siehe oben)
(Hohenheim) 相似文献