11,363 research outputs found
Linfield College: Study Abroad in France
This letter from returnee John F. Herrick explains the value of studying abroad in France
The state-of-the-art of electroencephalography and its role in manned space flight
Electroencephalography for determining competency of man during orbital space fligh
The eyes and optic paths of the catfish, ameiurus
No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49927/1/900750206_ftp.pd
Effect Of Orius insidiosus (Hemiptera: Anthocoridae) And Spinosad (Conserve®) On Western Flower Thrips, Frankliniella occidentalis (Thysanoptera: Thripidae), Populations In Transvaal Daisy Flowers
Western flower thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is a major insect pest of greenhouse-grown horticultural crops. Greenhouse producers typically apply insecticides to suppress WFT populations. However, continual reliance on insecticides can lead to the development of resistant in WFT populations. The insidious flower bug, Orius insidiosus (Say) (Hemiptera: Anthocoridae), is a commercially available predatory bug of WFT that offers an alternative to using insecticides for WFT suppression. Therefore, we investigated the efficacy of one or two O. insidiosus adults compared to spray applications of the standard insecticide, spinosad (Conserve®) in suppressing WFT adult populations in transvaal daisy (Gerbera jamesonii), cut-flowers under greenhouse conditions. Percent adult WFT mortality was significantly lower when one or two O. insidiosus adults were released into the flowers (mean range: 32 to 34%; n=747), compared to the untreated and water control (8 to 9%; n=431). The highest percent mortality of WFT adults was associated with the spinosad (Conserve®) treatment (100%; n= 203)
Experiment K-6-10. Effects of zero gravity on myofibril protein content and isomyosin distribution in rodent skeletal muscle
The purpose of this experiment was to investigate the effects of 12 days of zero gravity (0G) exposure (Cosmos 1887 Biosputnik) on the enzymatic properties, protein content, and isomyosin distribution of the myofibril fraction of the slow-twitch vastus intermedius (VI) and the fast-twitch vastus lateralis (VL) muscles of adult male rats. Measurements were obtained on three experimental groups (n=5 each group) designated as flight-group (FG), vivarium-control (VC), and synchronous-control (SC). Body weight of the FG was significantly lower than the two control groups (p less than 0.05). Compared to the two control groups, VI weight was lower by 23 percent (p less than 0.10); whereas no such reduction was observed for the VL muscle. Myofibril yields (mg protein/g of muscle) in the VI were 35 percent lower in the FG compared to the controls (p less than 0.05); whereas, no such pattern was apparent for the VL muscle. When myofibril yields were expressed on a muscle basis (mg/g x muscle weight), the loss of myofibril protein was more exaggerated and suggests that myofibril protein degradation is an early event in the muscle atrophy response to 0G. Analysis of myosin isoforms indicated that slow-myosin was the primary isoform lost in the calculated degradation of total myosin. No evidence of loss of the fast isomyosins was apparent for either muscle following space flight. Myofibril ATPase activity of the VI was increased in the FG compared to controls, which is consistent with the observation of preferential slow-myosin degradation. These data suggest that muscles containing a high percent of slow-twitch fibers undergo greater degrees of myofibril protein degradation than do muscles containing predominantly fast-twitch fibers in response to a relatively short period of 0G exposure, and the primary target appears to be the slow-myosin molecule
Breakup of meteoroids in the Venusian atmosphere and its effects on crater formation
Early results of the Magellan mission to Venus show that almost all of the observed impact craters appear to be unaffected by erosion, burial, and tectonic deformation. Therefore it is reasonable to assume that the observed paucity of small craters in the cumulative size-frequency distribution (SFD) relative to the simple power laws observed on airless planets is most likely due to atmospheric effects on the incoming meteoroids. A model was developed earlier for travel and breakup of a meteoroid in an atmosphere, but this model was never used to estimate a SFD. An attempt is made to match the cumulative SFD and the number and size distribution of multiple-floored craters and crater fields using this model
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