2,257 research outputs found

    Effect Of Orius insidiosus (Hemiptera: Anthocoridae) And Spinosad (ConserveÂź) On Western Flower Thrips, Frankliniella occidentalis (Thysanoptera: Thripidae), Populations In Transvaal Daisy Flowers

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    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 (ConserveÂź) 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 (ConserveÂź) treatment (100%; n= 203)

    Transcriptional inhibition of type I collagen gene expression in scleroderma fibroblasts by the antineoplastic drug ecteinascidin 743.

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    We previously showed that COL1A1 expression is up-regulated at the transcriptional level in systemic sclerosis (SSc) fibroblasts and that the CCAAT-binding factor (CBF) is involved in this increased expression. Ecteinascidin 743 (ET-743) is a chemotherapeutic agent that binds with sequence specificity to the minor groove of DNA and inhibits CBF-mediated transcriptional activation of numerous genes. Therefore, we examined the effects of ET-743 on the increased COL1A1 expression in SSc fibroblasts. The drug caused a potent and dose-dependent inhibition of type I collagen biosynthesis, which reached 70-90% at 700 pM without affecting cell viability. The same drug concentration caused 60-80% reduction in COL1A1 mRNA levels. The stability of the corresponding transcripts was not affected. In vitro nuclear transcription assays demonstrated a 54% down-regulation of COL1A1 transcription. Transient transfections with COL1A1 promoter constructs containing the specific CBF binding sequence into SSc cells previously treated with 700 pM ET-743 failed to show an effect on COL1A1 promoter activity. Furthermore, ET-743 did not affect the binding of CBF or Sp1 transcription factors to their cognate COL1A1 elements. However, treatment with 700 pM ET-743 of stably transfected NIH 3T3 cells expressing a human type II procollagen gene under the control of the human COL1A1 promoter caused a greater than 50% reduction in the production of type II procollagen and a similar decrease in the corresponding type II procollagen transcripts. These results indicate that ET-743 is a potent inhibitor of COL1A1 transcription. However, this effect cannot be explained by a direct effect on CBF binding to the COL1A1 promoter. Although the exact mechanisms responsible for the transcriptional inhibition of COL1A1 by ET-743 are not apparent, our observations suggest that the drug may be an effective agent to decrease collagen overproduction in SSc and other fibrotic diseases

    Etching silicon by SF₆ in a continuous and pulsed power helicon reactor

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    The etch rate of silicon by SF₆ in a helicon reactor has been measured along with simultaneous actinometric measurements of the concentration of atomic fluorine in the gas phase for a variety of gas flow rates resulting in pressures in the mTorr range. A bias rf power was applied to the substrate to investigate the effect of ion energy on the etch rate. The etch rate was found to be proportional to the fluorine concentration and independent of the bias for the higher gas flow rates. However, at lower flow rates, the situation was more complicated and no simple model can explain the measurements.Measurements of the etch rate were also made in the afterglow of a repetitively pulsed discharge so that the directed ion energy would be reduced to the thermal motion after the rapid collapse of the plasma potential. A simple model was developed to explain the temporal etching phenomena in terms of the lifetime of the atomic fluorine

    INVENTORY ACCURACY OF MAINTENANCE ASSISTANCE MODULES (MAMS) ON SHIPS UTILIZING THE ORGANIZATIONAL MAINTENANCE MANAGEMENT SYSTEM – NEXT GENERATION (OMMS-NG)

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    Proper inventory management is crucial to the success of a naval warship’s completion of mission tasking and maintenance operational readiness. All U.S. naval warships require a predetermined inventory of Maintenance Assistance Modules (MAMs) to test and identify broken parts within a weapons or engineering system when failures occur. Once a part is identified as broken, shipboard personnel order that part through the Navy Supply system and return the MAMs to their appropriate inventory location. These are high-value assets that require 100% inventory validity. Fleet Logistics Center San Diego has raised concerns due to declining inventory accuracy results of MAM inventories. This study contains an analysis of the differences in inventory management procedures between a variety of naval assets, ascertains the most efficient practice of inventory management, and presents possible explanations for the loss of these high-value assets. The authors have determined that there is a disparity between a ship’s inventory validities and Type Commander’s (TYCOM’s) inventory validities due to an inadequate inventory management system and insufficient guidance in procedures and policies for managing MAMs.Lieutenant Commander, United States NavyLieutenant Commander, United States NavyLieutenant Commander, United States NavyApproved for public release. Distribution is unlimited

    Intermanifold similarities in partial photoionization cross sections of helium

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    Using the eigenchannel R-matrix method we calculate partial photoionization cross sections from the ground state of the helium atom for incident photon energies up to the N=9 manifold. The wide energy range covered by our calculations permits a thorough investigation of general patterns in the cross sections which were first discussed by Menzel and co-workers [Phys. Rev. A {\bf 54}, 2080 (1996)]. The existence of these patterns can easily be understood in terms of propensity rules for autoionization. As the photon energy is increased the regular patterns are locally interrupted by perturber states until they fade out indicating the progressive break-down of the propensity rules and the underlying approximate quantum numbers. We demonstrate that the destructive influence of isolated perturbers can be compensated with an energy-dependent quantum defect.Comment: 10 pages, 10 figures, replacement with some typos correcte

    The Effects of an Acute Bout of Self-Myofascial Release on the Physiological Parameters of Running

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    International Journal of Exercise Science 13(3): 113-122, 2020. This study examined changes in the physiological parameters of running performance when self-myofascial release (SMR) was used prior to a submaximal run. A total of 16 male recreational runners, between the ages of 27 and 50 years old volunteered for the study. Participants had to complete a running event measuring a 10K or longer in the past 12 months and obtained a O2peakvalue of 45 mL·kg-lmin-1to be included in the study. Participants took part in two 40 min treadmill runs at 75% of their O2peak, one session with the use of SMR and the other with 20 min of seated rest prior to the run. Measurements of heart rate, blood lactate concentrations, ventilatory efficiency E/ O2), RPE, and running velocity were assessed. There was no statistically significant interaction or treatment effect for these variables when SMR was used prior to a 40 min treadmill run(p\u3e .05; heart rate: d = .01, E/ O2: d= .07, RPE: d= .07). Although no positive effects on running performance were found, the lack of negative effects suggests the use of SMR prior to running does not hinder performance

    Modularity map of the network of human cell differentiation

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    Cell differentiation in multicellular organisms is a complex process whose mechanism can be understood by a reductionist approach, in which the individual processes that control the generation of different cell types are identified. Alternatively, a large scale approach in search of different organizational features of the growth stages promises to reveal its modular global structure with the goal of discovering previously unknown relations between cell types. Here we sort and analyze a large set of scattered data to construct the network of human cell differentiation (NHCD) based on cell types (nodes) and differentiation steps (links) from the fertilized egg to a crying baby. We discover a dynamical law of critical branching, which reveals a fractal regularity in the modular organization of the network, and allows us to observe the network at different scales. The emerging picture clearly identifies clusters of cell types following a hierarchical organization, ranging from sub-modules to super-modules of specialized tissues and organs on varying scales. This discovery will allow one to treat the development of a particular cell function in the context of the complex network of human development as a whole. Our results point to an integrated large-scale view of the network of cell types systematically revealing ties between previously unrelated domains in organ functions.Comment: 32 pages, 7 figure
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