3,937 research outputs found

    Oviposition Preference of the Mimosa Webworm, Homadaula anisocentra (Lepidoptera: Plutellidae)

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    In the field, the mimosa webworm, Homadaula anisocentra Meyrick (Lepidoptera: Plutellidae), oviposits preferentially on branches or on leaf rachises or petioles of uninfested ornamental honeylocust, Gleditsia triacanthos L. On infested trees, oviposition occurs almost entirely on larval webbing. In the laboratory, uninfested mature leaves of both honeylocust and mimosa, Albizzia julibrissin Durazzini, are preferred over uninfested young leaves as oviposition sites. The addition of larval webbing to leaves of any age or to nonhost substrate induces oviposition preferentially on the webbin

    Library Web Development: A Decade in Review

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    Objective: This poster examines how academic medical libraries have presented their web sites over the past decade: 1) How have advances in web technologies influenced the “look and feel” of the web site? 2) What other developments contributed to the evolution of medical library web sites? 3) How has the librarian\u27s role in web development changed in the last ten years? Method: Reviewing the history of the web and developments in new technology, we will note significant turning points in the design of our own library web site and that of other institutions of a similar size and mission. Using data and images from the Way Back Machine at www.archive.org we will plot how changes in technology effect: what information is presented, page layout and usability. We will examine how changes in librarianship and the “information explosion” have helped the medical library web site progress. Results: From examining our own web site history we have determined that we were slow to implement new design technologies. Many of the technologies that were initially incorporated into the web page design improved on graphical elements at first. Improvements on layout, searching and form design soon followed. In 2000 a new underlining database structure (Cold Fusion) was added to the web site that allowed staff to better manage the large number of e-resources the Library provided. Once a full time position dedicated to web management was created our web site was able to focus on layout and usability. Conclusion: From looking at other web sites of similar size we have determined that many Libraries web sites progressed first as an “online directory” providing basic information, to a page that started to offer services such as request forms and links to an OPAC and/or Medline, to finally a dynamic page with electronic books, journals and databases. Many institutions offer customized pages for individual users. Additional research is recommended

    Decay estimates for variable coefficient wave equations in exterior domains

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    In this article we consider variable coefficient, time dependent wave equations in exterior domains. We prove localized energy estimates if the domain is star-shaped and global in time Strichartz estimates if the domain is strictly convex.Comment: 15 pages. In the new version, some typos are fixed and a minor correction was made to the proof of Lemma 1

    Spatial Filter Approach to Evaluating the Role of Convection on the Evolution of a Mesoscale Vortex

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    A new spatial filter is proposed that exploits a spectral gap in power between the convective scale and the system (‘‘vortex’’) scale during tropical cyclone (TC) genesis simulations. Using this spatial separation, this study analyzes idealized three-dimensional numerical simulations of deep moist convection in the presence of a symmetric midlevel vortex to quantify and understand the energy cascade between the objectively defined convective scale and system scale during the early stages of tropical cyclogenesis. The simulations neglect surface momentum, heat, and moisture fluxes to focus on generation and enhancement of vorticity within the interior to more completely close off the energy budget and to be consistent for comparison with prior benchmark studies of modeled TC genesis. The primary contribution to system-scale intensification comes from the convergence of convective-scale vorticity that is supplied by vortical hot towers (VHTs). They contribute more than the convergence of system-scale vorticity to the spinup of vorticity in these simulations by an order of magnitude. Analysis of the change of circulation with time shows an initial strengthening of the surface vortex, closely followed by a growth of the mid- to upper-level circulation. This evolution precludes any possibility of a stratiform precipitation–induced top-down mechanism as the primary contributor to system-scale spinup in this simulation. Instead, an upscale cascade of rotational kinetic energy during vortex mergers is responsible for spinup of the simulated mesoscale vortex. The spatial filter employed herein offers an alternative approach to the traditional symmetry–asymmetry paradigm, acknowledges the highly asymmetric evolution of the systemscale vortex itself, and may prove useful to future studies on TC genesis

    Ultrasound-mediated transdermal drug delivery: Mechanisms, scope, and emerging trends

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    The use of ultrasound for the delivery of drugs to, or through, the skin is commonly known as sonophoresis or phonophoresis. The use of therapeutic and high frequencies of ultrasound (≄ 0.7 MHz) for sonophoresis (HFS) dates back to as early as the 1950s, while low-frequency sonophoresis (LFS, 20–100 kHz) has only been investigated significantly during the past two decades. Although HFS and LFS are similar because they both utilize ultrasound to increase the skin penetration of permeants, the mechanisms associated with each physical enhancer are different. Specifically, the location of cavitation and the extent to which each process can increase skin permeability are quite dissimilar. Although the applications of both technologies are different, they each have strengths that could allow them to improve current methods of local, regional, and systemic drug delivery. In this review, we will discuss the mechanisms associated with both HFS and LFS, specifically concentrating on the key mechanistic differences between these two skin treatment methods. Background on the relevant physics associated with ultrasound transmitted through aqueous media will also be discussed, along with implications of these phenomena on sonophoresis. Finally, a thorough review of the literature is included, dating back to the first published reports of sonophoresis, including a discussion of emerging trends in the field.National Institutes of Health (U.S.) (Grant EB-00351)Massachusetts Institute of Technology. Institute for Soldier Nanotechnologies (Grant DAAD-19-02-D-002

    Interferometric Studies of the extreme binary, Ï”\epsilon Aurigae: Pre-eclipse Observations

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    We report new and archival K-band interferometric uniform disk diameters obtained with the Palomar Testbed Interferometer for the eclipsing binary star Ï”\epsilon Aurigae, in advance of the start of its eclipse in 2009. The observations were inteded to test whether low amplitude variations in the system are connected with the F supergiant star (primary), or with the intersystem material connecting the star with the enormous dark disk (secondary) inferred to cause the eclipses. Cepheid-like radial pulsations of the F star are not detected, nor do we find evidence for proposed 6% per decade shrinkage of the F star. The measured 2.27 +/- 0.11 milli-arcsecond K band diameter is consistent with a 300 times solar radius F supergiant star at the Hipparcos distance of 625 pc. These results provide an improved context for observations during the 2009-2011 eclipse.Comment: Accepted for Ap.J. Letters, Oct. 200

    Characterising the vertical separation of shale-gas source rocks and aquifers across England and Wales (UK)

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    Shale gas is considered by many to have the potential to provide the UK with greater energy security, economic growth and jobs. However, development of a shale gas industry is highly contentious due to environmental concerns including the risk of groundwater pollution. Evidence suggests that the vertical separation between exploited shale units and aquifers is an important factor in the risk to groundwater from shale gas exploitation. A methodology is presented to assess the vertical separation between different pairs of aquifers and shales that are present across England and Wales. The application of the method is then demonstrated for two of these pairs—the Cretaceous Chalk Group aquifer and the Upper Jurassic Kimmeridge Clay Formation, and the Triassic sandstone aquifer and the Carboniferous Bowland Shale Formation. Challenges in defining what might be considered criteria for ‘safe separation’ between a shale gas formation and an overlying aquifer are discussed, in particular with respect to uncertainties in geological properties, aquifer extents and determination of socially acceptable risk levels. Modelled vertical separations suggest that the risk of aquifer contamination from shale exploration will vary greatly between shale–aquifer pairs and between regions and this will need to be considered carefully as part of the risk assessment and management for any shale gas development
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