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81.
Pheromone‐based mating disruption of lepidopteran pests (Tortricidae) of pome fruits using hand‐applied dispensing systems has become standard management practice for many producers in western North America. Sprayable microencapsulated (MEC) pheromone formulations that enable the application of pheromone controls with other orchard sprays and assist in the development of multispecies mating‐disruption systems are currently under development. Responses of male Choristoneura rosaceana (Harris) and Pandemis limitata (Robinson) (Lepidoptera: Tortricidae) to calling females in clean air, and air treated with their major pheromone component (Z)‐11‐tetradecenyl acetate (Z11‐14:OAc), released from a 3M sprayable pheromone formulation containing proprietary 3M Phase I microcapsules, applied at doses of 1, 10, and 100 mg of active ingredient (ai) m?2 to the upwind end of a flight tunnel (equivalent to field rates of 10, 100, and 1000 g ai ha?1) were compared in laboratory flight tunnels. In both species, disorientation was found to be dose‐dependent, because relative to male orientation to calling females in clean air, the orientation of male P. limitata was disrupted 23.3, 46.3, and 71.3%, and orientation by male C. rosaceana was disrupted 31.6, 37.7, and 45.8% by treatment doses of 1, 10, and 100 mg m?2, respectively. Latency of male responses to calling females in a background of Z11‐14:OAc relative to responses in clean air was also dose‐dependent. Albeit short, the disruption lasted 26, 74, and 218 h in P. limitata and 30, 54, and 174 h in C. rosaceana at each application rate, respectively. Disruption by pheromone treatment was greater in P. limitata than in C. rosaceana. This difference may be correlated with species’ differences in the pheromone release rates of females. Mechanisms of disruption invoked by this 3M MEC pheromone formulation are discussed in relation to issues of its longevity and observed differences in the effects against the two species. It appears possible to evaluate relative activity of MEC pheromones in a laboratory setting which may aid in development of new formulations for mating disruption.  相似文献   
82.
Marmor  M.S.  Martin  C.E. 《Photosynthetica》1998,35(4):589-596
Tomato seeds exposed to space conditions for nearly six years on board the Long Duration Exposure Facility (LDEF) satellite were subsequently germinated and the resultant seedlings grown on earth under controlled conditions for analysis. Photosynthesis, biomass, and water relations were compared between mature plants grown from earth-based control seeds and space-exposed seeds under both well-watered and drought-stressed conditions. No consistent significant differences in photosynthesis and water relations were observed in the two sets of plants at any level of drought stress. Fruit production, however, though limited and variable, was significantly greater in plants grown from space-exposed seeds than in plants grown from earth-based seeds. Overall, exposure of seeds to space had only minor effects on the physiology and growth of plants grown from such seed.  相似文献   
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In the emergency treatment of a patient with multiple severe injuries who is brought to a physician''s office from the scene of an accident, the physician must make sure that a way for air to reach the lungs is open, must treat or prevent shock, stop hemorrhage and apply temporary splints to fractures of the extremity.The possibility that the tip of the tongue is blocking the pharynx and that blood or other fluid is clogging the airway must be considered. Fluids should be administered intravenously to prevent shock and gauze pads should be held firmly in place to control bleeding.  相似文献   
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Abstract — Morphological characters from sabethine mosquitoes were coded from larvae, pupae and adults, and life-stage partitions were evaluated to determine the contribution of each to the topology of a combined cladogram. Initial tests failed to find congruence between characters partitioned by life stage. However, when components from the combined analysis were tested using reduced taxon sets, a high degree of concordance between partitions was observed. A procedure for assessing individual life-stage contribution is employed, in which exhaustive searches are used to explore all possible arrangements for each of the selected components. Seven of the 10 components examined were able to recover the combined topology with a reduced taxon set. Congruent arrangements of taxa were typically observed for two or more life stages, although partitioned data were less resolved and frequently included aberrant topologies (those not supported by other partitioned or combined reduced taxon tree sets). In addition, none of the partitioned data sets gave robust results for all tests, suggesting that studies which emphasize character data from single life stages may support misleading arrangements of taxa. One component on the combined cladogram was not supported by any of the life-stage partitions when analysed separately. These results are complementary to “total evidence” approach, and demonstrate that partitions of data are useful for examining suits of characters which may cause some components of the “total  相似文献   
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Farming is among the three most hazardous occupations in modern society and perhaps also held a similar position during the medieval period. The goal of this study was to determine if there is a significant difference in frequencies and patterns of longbone fracture trauma observed between rural and urban activity bases that distinguish farming as a particularly dangerous occupation during the medieval period. The longbones of 170 individuals excavated from Raunds, a rural medieval British site (10th–12th centuries AD) were examined for fractures and compared to data collected from four contemporary British medieval sites, one rural and three urban. The fracture frequency for the Raunds individuals (19.4%) was significantly different from the urban sites (4.7–5.5%). Female fractures were characterized by injury to the forearm, while the males were predisposed to diverse fracture locations. Clinical research provided a source of documented farm-related trauma from North America and Europe where the crops and animals raised, the manual chores performed, and the equipment used in traditional or small-scale farms have changed little in form or function since the medieval period. Nonmechanized causes of injury contribute to approximately 40% of all modern farm-related injuries and are attributed to falls from lofts and ladders, animal assaults and bites, and falls from moving vehicles. These hazardous situations were also present in the medieval period and may explain some of the fracture trauma from the rural sites. A high fracture frequency for both medieval males and females is significantly associated with farming subsistence when compared to craft-orientated urban dwellers. Am J Phys Anthropol 109:229–243, 1999. © 1999 Wiley-Liss, Inc.  相似文献   
90.
Some populations in Washington's Puget Sound area consume much more seafood than the general population. Mean consumption rates are 61?g/person/day for the Tulalip and Squaxin Island Tribes and 117.2?g/person/day for Asian and Pacific Islanders (API). There is concern about possible health risks from seafood PCB exposure for these groups, but exposure evaluation is difficult due to inadequacies of environmental data. Available seafood PCB data were matched to results from recent seafood consumption surveys. To rate quality of matches and identify data gaps, a ranking system based on species specificity, data quality, and location compatibility was developed. Sensitivity of total PCB and congenerspecific PCB testing (for use in TCDD toxic equivalency approaches) necessary for cancer risk assessment was explored and included in the ranking scheme. For the Squaxin Tribe, appropriate total PCB data for risk assessment were available for 58% of seafood consumed, which is dominated by local salmon. For API, appropriate total PCB data were identified for only 4% of seafood consumed, which is dominated by commercial shellfish. Insufficient sensitivity of commercial seafood PCB analysis and overall lack of sufficiently sensitive PCB congener analysis are major gaps in ability to characterize PCB exposure and risk for these groups.  相似文献   
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