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21.
Ohne Zusammenfassung 相似文献
22.
Prof. Dino Rui 《Journal of pest science》1956,29(1):1-2
Ohne Zusammenfassung 相似文献
23.
Prof. Dr. L. Schwarz 《Journal of pest science》1936,12(4):46-46
Ohne Zusammenfassung
Mit 2 Abbildungen 相似文献
24.
Prof. LUO You-qing 《中国林学(英文版)》2008,10(1):I0003-I0003
About 8.7 million hm^2 of forests in China was ravaged by plant diseases and insect pests each year, resulting in an economic loss of RMB 88 billion. Global warming, frequent abnormal weather and closer international economic and trade ties have aggravated the damage of plant diseases and insects on China＇s forests over the past few years. 相似文献
25.
Hanna Werhahn Engel F. HesselHanna Schulze MSc Herman F.A. Van den Weghe Prof Dr Ir 《Journal of Equine Veterinary Science》2011,31(7):417-425
In Germany, most competition horses are housed in single stalls and free exercise is not permitted in many cases. The reason for not allowing free exercise is mostly the risk of injury. Additionally, opinions exist that the horses’ demand for exercise is fulfilled by training and that the horses’ willingness to perform is negatively influenced by free exercise. In the present study, three turnout practices were investigated with regard to their effect on the behavior of four horses: daily training without free exercise (no turnout), 2-hour turnout (for free exercise) before training, and 2-hour turnout after training. The aim of this study was to determine any differences in the horses’ behavior between the three treatments. The horses’ behavior in the stable was observed through video recordings. The behavior during turnout was observed directly and during training was evaluated by the riders with the aid of a questionnaire. Additionally, the distance covered during turnout was measured by Global Positioning System devices. The behavior within the stall was more restless in the treatment without turnout—which became apparent in significantly more frequent changes between behaviors as compared with the treatments with turnout. The results of Global Positioning System measurement during turnout showed a significantly shorter distance covered when horses were trained before they were turned out compared with turnout before training. If the horses were turned out after training, they also showed less trotting and cantering and more dozing. The horses’ willingness to perform was not significantly different between the three treatments. 相似文献
26.
Prof. Dr. C. W. Lutz 《European Journal of Forest Research》1923,45(6):219-226
Ohne Zusammenfassung 相似文献
27.
Susan Costantini Lucia Parrillo Eliana Guerriero Dominique Melck Giovanni Colonna Maria Grazia Volpe Marina Paolucci 《Aquaculture Nutrition》2018,24(1):524-538
1H‐NMR analysis of the hepatopancreas, muscle and haemolymph of Astacus leptodactylus after feeding with polyphenol‐enriched diet is reported. 1H‐NMR spectra of lipophilic extracts showed the presence of cholesterol, fatty acid residues, phospholipids and triglycerides. 1H‐NMR spectra of aqueous extracts identified 35 metabolites in the hepatopancreas, 31 in the muscle and 22 in the haemolymph. A total of 20 metabolites (amino acids and their derivatives) were present in the hepatopancreas, the muscle and the haemolymph. A total of 10 metabolites were present in both the hepatopancreas and the muscle (five amino acids, 2‐hydroxybutyrate, choline, myo‐inositol, glycogen and uracil). 2‐Hydroxyisobutyrate and creatine were present in both the hepatopancreas and the haemolymph. Phosphorylethanolamine, phosphocholine and fumarate were present only in the hepatopancreas and isoleucine only in the muscle. Statistical analysis showed that the percentage of weight gain was statistically higher in polyphenol‐enriched diet groups compared to the control and that polyphenols had a stimulating effect on the general metabolism. No stress‐related metabolites were higher in crayfish fed with polyphenol‐enriched diet. Conversely, phosphatidylcholine, cholesterol and DHA, linked to resistance to environmental stress and diseases, were higher compared to the control diet. This study indicates that 1H‐NMR is a useful tool to study the metabolomics in relation to diet differences. 相似文献
28.
Nelly Schmitt Frédéric Marin Jérôme Thomas Laurent Plasseraud Marina Demoy‐Schneider 《Aquaculture Research》2018,49(2):692-700
French Polynesia is renowned for the production of Tahitian black pearl. These gems are obtained by grafting a nucleus into the gonad of a receiving oyster together with a graft, i.e. a small section of mantle tissue of a donor oyster. This procedure initiates the formation of a pearl sack around the nucleus, and subsequently, the deposition of concentric layers of nacre. The nucleus plays a key‐role in pearl formation and its characteristics influence markedly the quality of the final product. As it is manufactured from mollusc shells, it contains a small percentage of organics. In the present paper, we used a set of biochemical techniques to characterize and compare the organic matrices from two types of nuclei that are currently used in French Polynesia: that from the freshwater mussel Amblema sp., and that from the pearl oyster Pinctada sp. To this end, we extracted the matrices from nuclei and performed FT‐IR, monodimensional electrophoresis, and enzyme‐linked immuno‐sorbent assay (ELISA). Our data show that the matrix associated with Amblema nuclei has a very different biochemical signature from that of Pinctada nuclei, a fact that may explain the improved tolerance of grafted oysters to nuclei of Pinctada origin. In the absence of complex physical methods of investigation, simple immunological techniques and FT‐IR performed on the extracted organic matrix are extremely reliable and effective for discriminating nuclei from these two sources. We assert that such techniques can be used as a diagnostic test to track unambiguously the biological origin of nuclei to avoid fraud. 相似文献
29.
Marina V. Mavromatis Mauricio Solano Michael Y. Thelen 《Veterinary radiology & ultrasound》2018,59(4):381-386
There are clear differences in the normal radiographic appearance of the abdominal organs between a left lateral vs. a right lateral view. While a few veterinary academic institutions have transitioned to a three‐view abdominal radiographic study protocol, obtaining only two views of the canine abdomen remains the current standard in veterinary medicine. In this combined retrospective and prospective, case‐controlled study, 48 canine patients presenting with signs of acute abdomen were recruited. Four board‐certified veterinary radiologists and four general practice veterinarians with greater than 3 years of experience in small animal practice were asked to determine if 10 predetermined findings were present within the set of images and if surgery was recommended based on those findings. Image readers were unaware of the clinical history. Three‐view studies did not yield statistically significantly greater accuracy than two‐view studies when evaluating all readers together. No statistically significant associations between the availability of the third view and increased accuracy or confidence were found in evaluations of general practitioners specifically. Evaluation of three‐view radiographic examination, as compared to two‐view examination, did not have perceived or statistically significantly increased diagnostic utility. Based on our findings, there is no statistically increased utility to justify a standard three‐view abdominal radiographic examination over a two‐view study for canines presenting with signs of acute abdomen. 相似文献
30.
Vesna Zupanc Gerhard Kammerer Helena Gr
man Igor &#x;antavec Rozalija Cveji&#x; Marina Pintar 《Land Degradation u0026amp; Development》2016,27(2):406-415
Hydropower plants on the lower river Sava, Slovenia, were developed without sealing the underground upstream. As a consequence, without the countermeasures of elevating and recultivating, the agricultural land on the river banks would be inundated because of the water‐table increase of the river. To remedy this, the fields were elevated and recultivated. The goal of this study was to assess soil quality and production potential after land raising and recultivation and to answer the question whether it is possible to recover soil quality and crop yield after large‐scale mass manipulation, such as land raising. After recultivation and after the second year of land reuse for the two cultures grass–clover mixture and corn on two sites, Middle Pijavsko and Lower Pijavsko, soil physical and chemical characteristics and crop yields were evaluated. Mixing of topsoil with the second horizon during removal and during backfill with filling material resulted in uneven soil fertility, plant growth and decreased yield. Driving on the refilled second layer with heavy machinery caused soil compaction in the Middle Pijavsko in spite of favourable soil texture (loam, 38·7% sand). On the areas with very high sand content (over 55%) and low clay content (10%), soil compaction was not as severe or persistent. Recultivation measures restored the agricultural land almost to the production potential prior to powerplant construction. Immediate intensive land use (corn) showed less favourable effect on soil characteristics. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献