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41.
Ground spiders on a cultivated field near Groβenzersdorf (Lower Austria) in the winter months 322 adult spiders caught with pitfall traps on a field near Groβenzersdorf in the period 3. X 1973–5. III 1974 showed: Erigonidae, Linyphiidae,Pachygnatha (Tetragnathinadae) are dominating. 19 spp. have been recognized, most of them being already known as eurochronous or diplochronous respectively. The whole spider fauna resembles very mmuch the situation found in mid-Germany (Leipzig) byGeiler (1963). 相似文献
42.
Spatial structure of wood composites in relation to processing and performance characteristics 总被引:1,自引:0,他引:1
Summary A rationale is presented for developing a mathematical model which describes a randomly packed, short-fibre-type wood composite. The model will utilize probability theory to insure random packing both in terms of flake position and orientation. Knowledge about the spatial relationship between wood elements will be used, in future, to predict a number of physical parameters associated with the composite structure. This will be accomplished by first developing a single-layer-flake model and subsequently proceeding to a multi-layer mat structure.Financial support for this work from NSERC/Canada through a strategic research grant is gratefully acknowledged 相似文献
43.
An immersion technique for studying wood wettability 总被引:1,自引:1,他引:1
Summary The wetting properties of wood were studied by a modification of the Wilhelmy technique. This method involved continuously monitoring the force exerted on a wood specimen as it was immersed at a controlled rate into a liquid. Wettability was expressed in terms of the area under the force-immersion curve and was referred to in this study as wettability index. The applicability of the technique was demonstrated for padauk and white spruce wood specimens heated for various time periods. The wettability of these woods in both distilled water and sodium hydroxide solutions decreased with increasing heating time. Sodium hydroxide solution yielded higher wettability index values, indicating that it was a better wetting agent than distilled water. The pH of the sodium hydroxide solution had a strong influence on magnitude of the wettability index. The possibility of using the technique for examining wood surface inactivation in relation to bonding with different adhesives is discussed.The authors gratefully acknowledge the assistance of Dr. W. G. Warren and his staff for the statistical analyses and curve fitting. Dr. Casilla also expresses his gratitude to the National Research Council of Canada and to the Canadian Forestry Service, Department of the Environment, for a postdoctoral fellowship 相似文献
44.
Hans Steiner 《Journal of pest science》1968,41(9):129-131
Zusammenfassung Nach einer neueren Definition der integrierten Sch?dlingsbek?mpfung werden die Voraussetzungen genannt, die zur praktischen
Anwendung dieses Verfahrens notwendig sind. Die Feststellung und Benützung wirtschaftlicher Schadensschwellen ist dabei besonders
wichtig. Ferner wird auf die Bedeutung der richtigen Wahl chemischer Pflanzenschutzmittel hingewiesen, solange selektive Pr?parate
noch nicht entwickelt und biologische Bek?mpfungsverfahren noch nicht praxisreif sind. Nicht eine pl?tzliche Umstellung von
der konventionellen zur integrierten Sch?dlingsbek?mpfung ist erstrebenswert, sondern ein schrittweises Vorgehen, das den
jeweiligen M?glichkeiten angepa?t werden mu?. Damit k?nnen auch jetzt schon beachtliche Erfolge erzielt werden.
Summary A new definition of the integrated control concept is given and the perequisites for practical application are mentioned. Knowledge and use of economic injury levels is of vital importance in this respect. Furthermore, the importance of the choice of pesticides to be used is stressed, as selective materials are not available yet, and purely biological control can not yet be applied in practice. A change from the conventional chemical pest control system into an integrated pest control system has to be realized step by step according to increasing knowledge and experience. With this integrated control system remarkable results have been obtained.
Résumé Après avoir établi une définition de la lutte integrée, l'auteur indique les conditions à remplir pour l'application pratique de cette méthode. La détermination et l'emploi de seuils de tolérance économiques est particulièrement important. En outre l'importance du choix judicieux des produits antiparasitaires chimiques est soulignée, compte tenu du fait des produits sélectifs ne sont pas encore développés et des procédés de lutte biologique pas encore m?rs pour la pratique. Un changement rapide de la lutte conventionelle à la lutte integrée n'est pas désirable, mais plut?t une évolution progressive qui soit adapté au fur et à mesure aux possibilités du moment. Ainsi, des succés considérables peuvent déjà être obtenus à brève échéance.相似文献
45.
Hyperlipidaemia refers to an increased concentration of lipids in the blood. Hyperlipidaemia is common in dogs and has recently emerged as an important clinical condition that requires a systematic diagnostic approach and appropriate treatment. Hyperlipidaemia can be either primary or secondary to other diseases. Secondary hyperlipidaemia is the most common form in dogs, and it can be a result of endocrine disorders, pancreatitis, cholestasis, protein‐losing nephropathy, obesity, as well as other conditions and the use of certain drugs. Primary hyperlipidaemia is less common in the general canine population but it can be very common within certain breeds. Hypertriglyceridaemia of Miniature Schnauzers is the most common form of primary hyperlipidaemia in dogs but other breeds are also affected. Possible complications of hyperlipidaemia in dogs include pancreatitis, liver disease, atherosclerosis, ocular disease and seizures. Management of primary hyperlipidaemia in dogs is achieved by administration of ultra low‐fat diets with or without the administration of lipid lowering drugs such as omega‐3 fatty acids, fibrates, niacin and statins. 相似文献
46.
ABSTRACT During formation of appressoria produced from conidia and ascospores of Venturia inaequalis, a dark brown ring structure was detected at the base of appressoria. This melanized appressorial ring structure (MARS) was attached to the leaf surface like a sealing ring and formed the fungus-plant interface; it is believed to be required for pathogen penetration of the cuticle. Neither germ tubes nor infection structures beneath the cuticle were found to be visibly melanized. MARS were formed not only on apple leaves but also on leaves of nonhost plants and artificial surfaces differing in hydrophobicity; the formation of appressoria and MARS was confined to hard surfaces. The melanin nature of the ring was confirmed by using melanin biosynthesis inhibitors. Applications prior to inoculation largely inhibited the melanization and reduced infection rate by 45 to 80%; curative applications were not effective. Transmission electron microscopy verified a localized melanization of the cell wall around the penetration pore, and melanin was incorporated into all layers of the fungal cell wall. Appressoria without MARS were not able to infect the plant, suggesting that this structure can be considered to be a pathogenicity factor in V. inaequalis. 相似文献
47.
48.
49.
R Kasimanickam S Schroeder M Assay V Kasimanickam DA Moore JM Gay WD Whittier 《Reproduction in domestic animals》2014,49(5):775-782
The objectives were (i) to evaluate the effect of temperament, determined by modified 2‐point chute exit and gait score, on artificial insemination (AI) pregnancy rates in beef heifers following fixed time AI and (ii) to determine the effect of temperament on cortisol, substance‐P, prolactin and progesterone at initiation of synchronization and at the time of AI. Angus beef heifers (n = 967) at eight locations were included in this study. At the initiation of synchronization (Day 0 = initiation of synchronization), all heifers received a body condition score (BCS), and temperament score (0 = calm; slow exit and walk or 1 = excitable; fast exit or jump or trot or run). Blood samples were collected from a sub‐population of heifers (n = 86) at both synchronization initiation and the time of AI to determine the differences in serum progesterone, cortisol, prolactin and substance‐P concentrations between temperament groups. Heifers were synchronized with 5‐day CO‐Synch+ controlled internal drug release (CIDR) protocol and were inseminated at 56 h after CIDR removal. Heifers were examined for pregnancy by ultrasound 70 days after AI to determine AI pregnancy. Controlling for synchronization treatment (p = 0.03), facility design (p = 0.05), and cattle handling facility design by temperament score interaction (p = 0.02), the AI pregnancy differed between heifers with excitable and calm temperament (51.9% vs 60.3%; p = 0.01). The alley‐way with acute bends and turns, and long straight alley‐way had lower AI pregnancy rate than did the semicircular alley‐way (53.5%, 56.3% and 67.0% respectively; p = 0.05). The serum hormone concentrations differed significantly between different types of cattle handling facility (p < 0.05). The cattle handling facility design by temperament group interactions significantly influenced progesterone (p = 0.01), cortisol (p = 0.01), prolactin (p = 0.02) and substance‐P (p = 0.04) both at the initiation of synchronization and at the time of AI. Inter‐ and intra‐rater agreement for temperament scoring were moderate and good (Kappa = 0.596 ± 0.07 and 0.797 ± 0.11) respectively. The predictive value for calm and pregnant to AI was 0.87, and excited and non‐pregnant to AI was 0.76. In conclusion, the modified 2‐point temperament scoring method can be used to identify heifers with excitable temperament. Heifers with excitable temperament had lower AI pregnancy. Further, cattle handling facility design influenced the temperament and AI pregnancy. 相似文献
50.
JI Yun HJ Park MH Park MS Kim JH Choi E Lee SP Gong JM Lim ST Lee 《Reproduction in domestic animals》2014,49(5):705-710
Recently, isolation and in vitro culture of putative spermatogonial stem cells (SSCs) in the domestic cat have been conducted. However, the cellular niche conditions that facilitate the establishment and long‐term maintenance of feline SSCs (FSSCs) have not been described. Therefore, we investigated the type of feeder cells used to stimulate colony formation and growth of FSSCs among the various factors in the FSSC niche. Spermatogonial stem cells isolated from feline testes were cultured on mitotically inactivated testicular stromal cells (TSCs) derived from cats, dogs and mice, and mouse embryonic fibroblasts (MEFs). The formation and growth of colonies derived from SSCs cultured on each type of feeder cell were identified at passage 0, and the morphology, alkaline phosphatase (AP) activity and expression of SSC‐specific genes in surviving colonies were investigated at passage 4. Among these diverse feeder cells, TSCs from cat showed the greatest colony formation, growth and maintenance of FSSCs, and SSC colonies cultured by passage 4 showed a typical dome‐shaped morphology, AP activity and expression of SSC‐specific genes (NANOG, OCT4, SOX2 and CD9). Accordingly, these results demonstrate that feline TSCs could be used as feeder cells to support the establishment and maintenance of SSCs from domestic cats. 相似文献