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Sample records for mac robertson land

  1. A Record of Holocene Paleoclimate Evolution from Robertson Bay, Victoria Land, Antarctica

    Science.gov (United States)

    Riesselman, C. R.; Truax, O.; Wilson, G. S.; Parker, R. L.; Yoo, K. C.; Lee, J. I.; Levy, R. H.; Mckay, R. M.

    2017-12-01

    Regionally representative records of how Antarctica responded to the transition from the Last Glacial Maximum into the Holocene are an essential component of understanding the processes by which the Antarctic cryosphere responds to a changing climate. Here, we present a high-resolution record of Holocene Antarctic paleoclimate evolution from a previously unstudied section of the Victoria Land margin. In 2015 the Korea Polar Research Institute collected a 571 cm sediment core, GC57, from Robertson Bay, a protected embayment west of Cape Adare and adjacent to the outlet glaciers of the Transantarctic Mountains. Using diatom assemblages, bulk sediment geochemistry, and the magnetic properties of GC57, we aim to reconstruct the response of the East Antarctic Ice Sheet to warming associated with deglaciation and the Holocene climatic optima at the interface between the Ross Sea and the Southern Ocean. Our multiproxy approach allows us to study sea ice extent, seasonality, ocean stratification and circulation, and primary productivity from the mid-Holocene (7,400 14C year BP) to the present. A sea-ice associated diatom assemblage indicative of summer sea surface temperatures below 0˚C dominates the basal section of GC57. Although diatoms are well preserved, the unit is characterized by low wt% biogenic silica (average 9%) and a high concentration of magnetic minerals, indicating that biogenic production persisted despite substantial terrigenous input into the bay. A rapid transition at 4708 14C yr BP is identified by a steep increase in wt% BSi (average 13%), a decrease in magnetic minerals, and a subtle assemblage change towards sea-ice associated diatoms with slightly warmer temperature tolerances. The novel ramped pyrolosis 14C dating methodology allows us to date the carbon fixed concurrent with deposition and generate a robust age model for GC57 with an accuracy previously difficult to achieve given the uncertainties associated with dating bulk acid insoluble

  2. Stable isotope and hydrogeochemical studies of Beaver Lake and Lake Radok, MacRobertson Land, East Antarctica

    International Nuclear Information System (INIS)

    Wand, U.; Hermichen, W.D.; Hoefling, R.; Muehle, K.

    1987-01-01

    Beaver Lake and Lake Radok, the largest known epishelf and the deepest freshwater lake on the Antarctic continent, respectively, were isotopically (δ 2 H, δ 18 O) and hydrogeochemically studied. Lake Radok is an isothermal and non-stratified, i.e. homogeneous water body, while Beaver Lake is stratified with respect to temperature, salinity and isotopic composition. The results for the latter attest to freshwater (derived from snow and glacier melt) overlying seawater. (author)

  3. Stable isotope and hydrogeochemical studies of Beaver Lake and Radok Lake, MacRobertson Land, East Antarctica

    International Nuclear Information System (INIS)

    Wand, U.; Hermichen, W.D.

    1988-01-01

    Beaver Lake and Radok Lake, the largest known epishelf lake and the deepest freshwater lake on the Antarctic continent, respectively, were isotopically (δ 2 H, δ 18 O) and hydrogeochemically studied. Radok Lake is an isothermal and nonstratified, i.e. homogeneous water body, while Beaver Lake is stratified with respect to temperature, salinity and isotopic composition. The results for the latter attest to freshwater (derived from snow and glacier melt) overlying seawater. (author)

  4. Celebrating Stephen Robertson's retirement

    NARCIS (Netherlands)

    Hiemstra, Djoerd; Tait, J.; MacFarlane, A; Belkin, N.

    2013-01-01

    Stephen Robertson retired from the Microsoft Research Lab in Cambridge during the summer of 2013 after a long career as one of the most influential, well-liked and eminent researchers in Information Retrieval throughout the world.

  5. Mac Bible

    CERN Document Server

    Spivey, Dwight

    2009-01-01

    This essential guide answers all your questions on using a Macintosh computer, whether you?re unpacking your very first Mac after switching from a PC or upgrading from an older Mac. You?ll walk through all pre-installed Mac applications, including using Mac OS X, browsing the Web using Safari, downloading music from the iTunes store, troubleshooting Mac-specific problems, organizing photos in iPhoto, organizing calendars in iCal, editing digital video in iMovie, and more.

  6. Averaging Robertson-Walker cosmologies

    International Nuclear Information System (INIS)

    Brown, Iain A.; Robbers, Georg; Behrend, Juliane

    2009-01-01

    The cosmological backreaction arises when one directly averages the Einstein equations to recover an effective Robertson-Walker cosmology, rather than assuming a background a priori. While usually discussed in the context of dark energy, strictly speaking any cosmological model should be recovered from such a procedure. We apply the scalar spatial averaging formalism for the first time to linear Robertson-Walker universes containing matter, radiation and dark energy. The formalism employed is general and incorporates systems of multiple fluids with ease, allowing us to consider quantitatively the universe from deep radiation domination up to the present day in a natural, unified manner. Employing modified Boltzmann codes we evaluate numerically the discrepancies between the assumed and the averaged behaviour arising from the quadratic terms, finding the largest deviations for an Einstein-de Sitter universe, increasing rapidly with Hubble rate to a 0.01% effect for h = 0.701. For the ΛCDM concordance model, the backreaction is of the order of Ω eff 0 ≈ 4 × 10 −6 , with those for dark energy models being within a factor of two or three. The impacts at recombination are of the order of 10 −8 and those in deep radiation domination asymptote to a constant value. While the effective equations of state of the backreactions in Einstein-de Sitter, concordance and quintessence models are generally dust-like, a backreaction with an equation of state w eff < −1/3 can be found for strongly phantom models

  7. Les Robertson, CERN's LCG project manager

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    "The LCG will provide a vital test-bed for the new Grid computing technologies that are set to revolutionise the way scientists use the world's computing resources in areas ranging from fundamental research to medical diagnosis," said Les Robertson, CERN's LCG project manager. The Grid is a new method of sharing processing power between computers in centres around the world.

  8. Windows for Intel Macs

    CERN Document Server

    Ogasawara, Todd

    2008-01-01

    Even the most devoted Mac OS X user may need to use Windows XP, or may just be curious about XP and its applications. This Short Cut is a concise guide for OS X users who need to quickly get comfortable and become productive with Windows XP basics on their Macs. It covers: Security Networking ApplicationsMac users can easily install and use Windows thanks to Boot Camp and Parallels Desktop for Mac. Boot Camp lets an Intel-based Mac install and boot Windows XP on its own hard drive partition. Parallels Desktop for Mac uses virtualization technology to run Windows XP (or other operating systems

  9. Macs for dummies

    CERN Document Server

    Baig, Edward C

    2014-01-01

    Get the most out of your Mac with this comprehensive guide Macs For Dummies, 13th Edition is the ultimate guide to your Mac, fully updated to include information about the latest updates. The book walks you through troubleshooting, syncing mobile devices, integrating Windows, and more, so you can take advantage of everything Macs have to offer. Whether you're a new user, a recent convert, or you just want to get the most out of your Mac, this book puts all the information you need in one place. Discover what makes Macs superior computing machines. Learn the basics, from mastering the Dock and

  10. Realization of Robertson-Walker spacetimes as affine hypersurfaces

    International Nuclear Information System (INIS)

    Chen Bangyen

    2007-01-01

    Due to the growing interest in embeddings of spacetimes in higher dimensional spaces, we consider a special type of embedding. We prove that Robertson-Walker spacetimes can be embedded as centroaffine hypersurfaces and graph hypersurfaces in some affine spaces in such a way that the induced relative metrics are exactly the Lorentzian metrics on the Robertson-Walker spacetimes. Such realizations allow us to view Robertson-Walker spacetimes and their submanifolds as affine submanifolds in a natural way. Consequently, our realizations make it possible to apply the tools of affine differential geometry to study Robertson-Walker spacetimes and their submanifolds

  11. Mycobacterium Avium Complex (MAC)

    Science.gov (United States)

    ... sweat, and saliva red-orange (may stain contact lenses); can interfere with birth control pills. Many drug interactions. CAN MAC BE PREVENTED? The bacteria that cause MAC are very common. It is ...

  12. Mac OS X Forensics

    Science.gov (United States)

    Craiger, Philip; Burke, Paul

    This paper describes procedures for conducting forensic examinations of Apple Macs running Mac OS X. The target disk mode is used to create a forensic duplicate of a Mac hard drive and preview it. Procedures are discussed for recovering evidence from allocated space, unallocated space, slack space and virtual memory. Furthermore, procedures are described for recovering trace evidence from Mac OS X default email, web browser and instant messaging applications, as well as evidence pertaining to commands executed from a terminal.

  13. Enterprise Mac administrators guide

    CERN Document Server

    Smith, William

    2015-01-01

    IT departments everywhere will be integrating Macs and Mac OS X into their IT infrastructure and this book will tell them how to do it. It will serve as an authoritative, useful and frequently referenced book on Mac OS X administration.

  14. Enterprise Mac Administrator's Guide

    CERN Document Server

    Edge, Charles; Hunter, Beau

    2009-01-01

    Charles Edge, Zack Smith, and Beau Hunter provide detailed explanations of the technology required for large-scale Mac OS X deployments and show you how to integrate it with other operating systems and applications. Enterprise Mac Administrator's Guide addresses the growing size and spread of Mac OS X deployments in corporations and institutions worldwide. In some cases, this is due to the growth of traditional Mac environments, but for the most part it has to do with "switcher" campaigns, where Windows and/or Linux environments are migrating to Mac OS X. However, there is a steep cu

  15. Mac Security Bible

    CERN Document Server

    Kissell, Joe

    2010-01-01

    Your essential, no-holds-barred guide to Mac security threats and solutions. Myth number one: Macs are safer than PCs. Not really, says author Joe Kissell, named one of MacTech's "25 Most Influential People" in the Mac community for 2008. In this timely guide, he not only takes you beyond the myths, he also delves into the nitty-gritty of each potential threat, helping you weigh the pros and cons of the solutions you might choose. Learn to measure risk versus inconvenience, make informed decisions, and protect your Mac computers, your privacy, and your data with this essential guide.

  16. Tachyons in Robertson-Walker Cosmology

    CERN Document Server

    Tomaschitz, R

    1998-01-01

    Superluminal signal transfer is studied in the context of a preferred cosmic frame of reference provided by the galactic background. The receding galaxies constitute a frame of absolute rest, in which the energy of tachyons (faster-than-light particles) is unambiguously defined as a positive quantity. The causality violation which arises in relativistic tachyonic theories is avoided. We define interactions of particles and tachyons in terms of elastic head-on collisions and energy-momentum conservation. To compare the theory developed with existing relativistic theories, tachyons are studied at first in a Minkowski universe, and the causality of a superluminal communication process is analyzed. Then we discuss the dynamics of tachyons in a Robertson-Walker universe with linear expansion factor and negatively curved three-space. We point out the consequences that the space expansion has on tachyons, like a finite life-time in the frame of absolute rest, and multiple images in the rest frames of moving observer...

  17. Dissipative Boltzmann-Robertson-Walker cosmologies

    International Nuclear Information System (INIS)

    Hiscock, W.A.; Salmonson, J.

    1991-01-01

    The equations governing a flat Robertson-Walker cosmological model containing a dissipative Boltzmann gas are integrated numerically. The bulk viscous stress is modeled using the Eckart and Israel-Stewart theories of dissipative relativistic fluids; the resulting cosmologies are compared and contrasted. The Eckart models are shown to always differ in a significant quantitative way from the Israel-Stewart models. It thus appears inappropriate to use the pathological (nonhyperbolic) Eckart theory for cosmological applications. For large bulk viscosities, both cosmological models approach asymptotic nonequilibrium states; in the Eckart model the total pressure is negative, while in the Israel-Stewart model the total pressure is asymptotically zero. The Eckart model also expands more rapidly than the Israel-Stewart models. These results suggest that ''bulk-viscous'' inflation may be an artifact of using a pathological fluid theory such as the Eckart theory

  18. La lutte pour la terre macédonienne : un projet grec de 1909 The fight for Macedonian land: a greek plan of 1909

    Directory of Open Access Journals (Sweden)

    Spyros Karavas

    2012-05-01

    Full Text Available Comment « sauver » la Macédoine des Bulgares ? Le consul de Grèce à Serrès, Sachtouris, voit là, en 1909, un problème autant agraire que national. À cette question qui obsède les politiques grecs de son temps, il croit trouver une solution : acheter des tchifliks qui seraient ensuite partagés entre des paysans que les propriétaires hellènes se chargeraient « d’helléniser ». Conjoncture difficile, hausse des prix, manque de volonté des financiers, son plan reste inappliqué, en revanche les Jeunes-Turcs achèteront des terres pour « turquifier »... la Macédoine.How to « save » Macedonia from Bulgarians? The Greek consul at Serres, Sachtouris, sees in that question, in 1909, a problem that is national as much as it is agrarian. To this particular question, that obsesses Greek politician of his time, he believes that he has found a solution: buy tchifliks which would be then shared among farmers that the Greek owners would then try to turn into Hellenes. Due to the difficult economic situation, the rising prices, the lack of willingness on behalf of the financial contributors, his plans was never implemented, quite the contrary, it was the Young Turks who bought land in order to turn Macedonia...into a Turkish territory.Πώς να « σωθεί » η Μακεδονία από τους Βουλγάρους ; Ο πρόξενος της Ελλάδας στις Σέρρες, Σαχτούρης, το 1909 εντοπίζει ένα πρόβλημα τόσο αγροτικό όσο και εθνικό. Σ’αυτό το ερώτημα που βασανίζει τους έλληνες πολιτικούς της εποχής, πιστεύει ότι βρήκε τη λύση : την αγορά τσιφλικιών που κατόπιν θα μοιράζονταν σε αγρότες που οι έλληνες ιδιοκτήτες τους θα « εξελλήνιζαν ». Οι δύσκολες πε

  19. Mac at Work

    CERN Document Server

    Sparks, David

    2011-01-01

    Bridge the gap between using a Mac at home and at the office. Now that you love your Mac at home, you want to use one at the office without missing a beat of productivity or professionalism. This unique guide shows you how.  You'll find best Mac business practices for handling word processing, spreadsheet and presentation creation, task and project management, and graphics. The book also explores topics such as hardware maintenance, how to synchronize with multiple computers, data backup, and communication with Windows networks.: Covers the nuts and bolts of using a Mac at work, including sync

  20. Enterprise Mac Security Mac OS X Snow Leopard Security

    CERN Document Server

    Edge, Stephen Charles; Hunter, Beau; Sullivan, Gene; LeBlanc, Dee-Ann

    2010-01-01

    A common misconception in the Mac community is that Mac's operating system is more secure than others. While this might be true in certain cases, security on the Mac is still a crucial issue. When sharing is enabled or remote control applications are installed, Mac OS X faces a variety of security threats. Enterprise Mac Security: Mac OS X Snow Leopard is a definitive, expert-driven update of the popular, slash-dotted first edition and was written in part as a companion to the SANS Institute course for Mac OS X. It contains detailed Mac OS X security information, and walkthroughs on securing s

  1. Enterprise Mac Managed Preferences

    CERN Document Server

    Marczak, Edward

    2010-01-01

    Many systems administrators on the Mac need a way to manage machine configuration after initial setup and deployment. Apple's Managed Preferences system (also known as MCX) is under-documented, often misunderstood, and sometimes outright unknown by sys admins. MCX is usually deployed in conjunction with an OS X server, but it can also be used in Windows environments or where no dedicated server exists at all. Enterprise Mac Managed Preferences is the definitive guide to Apple's Managed Client technology. With this book, you'll get the following: * An example-driven guide to Mac OS X Managed Pr

  2. Singular perturbations of empty Robertson-Walker cosmologies

    International Nuclear Information System (INIS)

    Newman, R.P.A.C.

    1979-02-01

    An investigation is presented which concerns a class of cosmological models defined by McVittie (1931): the universe is envisaged as a set of galaxies, idealised as point particles, which provide singular perturbations of Robertson-Walker cosmologies. The perturbations are considered only to first order in the gravitational coupling constant (8πG)/c 2 . Attention will only be given to such perturbations of empty Robertson-Walker cosmologies. Chapter 1 summarises the observational support for the type of model employed and for the smallness of the quantities to be used as perturbation coefficients. Chapter 2 provides the prerequisite analysis of Robertson-Walker cosmologies. Perturbations of empty Robertson-Walker cosmologies of non-vanishing cosmical constant are considered in general in Chapter 3. The structure of McVittie's singularly perturbed Robertson-Walker cosmologies are considered in detail in Chapter 4. The remaining chapters seek to investigate them further by way of their optical properties. Chapter 5 provides the necessary theory of geometric optics with particular regard to the intensity and distortion of a beam of light, and Chapter 6 applies this theory to the McVittie cosmologies. Chapter 7 sees the definition of an averaging procedure which leads to expressions for the intensity and distortion of a typical beam of light from a point source. (author)

  3. Casimir densities for a boundary in Robertson-Walker spacetime

    Energy Technology Data Exchange (ETDEWEB)

    Saharian, A.A., E-mail: saharian@ictp.i [Department of Physics, Yerevan State University, 1 Alex Manoogian Street, 0025 Yerevan (Armenia); Setare, M.R., E-mail: rezakord@ipm.i [Department of Science of Bijar, University of Kurdistan, Bijar (Iran, Islamic Republic of)

    2010-04-12

    For scalar and electromagnetic fields we evaluate the vacuum expectation value of the energy-momentum tensor induced by a curved boundary in the Robertson-Walker spacetime with negative spatial curvature. In order to generate the vacuum densities we use the conformal relation between the Robertson-Walker and Rindler spacetimes and the corresponding results for a plate moving by uniform proper acceleration through the Fulling-Rindler vacuum. For the general case of the scale factor the vacuum energy-momentum tensor is presented as the sum of the boundary free and boundary induced parts.

  4. Casimir densities for a boundary in Robertson-Walker spacetime

    International Nuclear Information System (INIS)

    Saharian, A.A.; Setare, M.R.

    2010-01-01

    For scalar and electromagnetic fields we evaluate the vacuum expectation value of the energy-momentum tensor induced by a curved boundary in the Robertson-Walker spacetime with negative spatial curvature. In order to generate the vacuum densities we use the conformal relation between the Robertson-Walker and Rindler spacetimes and the corresponding results for a plate moving by uniform proper acceleration through the Fulling-Rindler vacuum. For the general case of the scale factor the vacuum energy-momentum tensor is presented as the sum of the boundary free and boundary induced parts.

  5. States of low energy on Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Olbermann, Heiner

    2007-01-01

    We construct a new class of physical states of the free Klein-Gordon field in Robertson-Walker spacetimes. This is done by minimizing the expectation value of smeared stress-energy. We get an explicit expression for the state depending on the smearing function. We call it a state of low energy. States of low energy are an improvement of the concept of adiabatic vacua on Robertson-Walker spacetimes. The latter are approximations of the former. It is shown that states of low energy are Hadamard states

  6. Integral constraints on perturbations of Robertson-Walker cosmologies

    International Nuclear Information System (INIS)

    Ellis, G.F.R.; Jaklitsch, M.J.

    1989-01-01

    Integral constraints occur in the case of spherically symmetric inhomogeneities in Robertson-Walker universes, and (according to Traschen) in the case of general perturbations of these models. It is shown that these constraints are the same in the case of spherical symmetry, and they are interpreted as 'fitting conditions', that is, as constraints on the background Robertson-Walker model rather than on the nature of inhomogeneities. These integral constraints significantly affect the interpretation of anisotropies in the cosmic microwave background radiation. 22 refs

  7. The effects of Poynting–Robertson drag on solar sails

    Directory of Open Access Journals (Sweden)

    F.A. Abd El-Salam

    2018-06-01

    Full Text Available In the present work, the concept of solar sailing and its developing spacecraft are presented. The effects of Poynting–Robertson drag on solar sails are considered. Some analytical control laws with some mentioned input constraints for optimizing solar sails dynamics in heliocentric orbit using Lagrange’s planetary equations are obtained. Optimum force vector in a required direction is maximized by deriving optimal sail cone angle. New control laws that maximize thrust to obtain certain required maximization in some particular orbital element are obtained. Keywords: Poynting–Robertson drag, Solar sail, Control laws, Optimal sail, Cone angle

  8. The Robertson Karoo as pastural area | JGV | African Journal of ...

    African Journals Online (AJOL)

    In the Robertson Karoo eight plant communities can he distinguished. Quantitative plant surveys were conducted in all the communities. Succulents form an important component of the vegetation. The plant communities are very stable after invasion by succulents which tend to remain dominant more or less permanently.

  9. Future null infinity of Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Moreschi, O.M.

    1988-08-01

    The future null infinity for all non-contracting Robertson-Walker space time is studied systematically. A theorem is proved which establishes the expected relation between the nature of J + and the appearance or absence of cosmic event horizons. (author). 7 refs, 1 tab

  10. Quantization of Robertson-Walker geometry coupled to fermionic matter

    International Nuclear Information System (INIS)

    Christodoulakis, T.; Zanelli, J.

    1983-06-01

    A Robertson-Walker universe coupled to a spin 1/2 Dirac field is quantized following Dirac's formalism for constrained Hamiltonian systems. It is found that in nearly all cases it can be asserted that the universe avoids the collapse. (author)

  11. Infinitesimal conformal closed transformations of de Sitter and Robertson-Walker cosmological spaces

    International Nuclear Information System (INIS)

    Sakoto, Moussa

    1976-01-01

    The infinitesimal conformal closed transfromations of de Sitter and Robertson-Walker cosmological spaces are determined and an interesting property of the current lines for Robertson-Walker spaces is given [fr

  12. MAC calorimeters and applications

    International Nuclear Information System (INIS)

    MAC Collaboration.

    1982-03-01

    The MAC detector at PEP features a large solid-angle electromagnetic/hadronic calorimeter system, augmented by magnetic charged-particle tracking, muon analysis and scintillator triggering. Its implementation in the context of electron-positron annihilation physics is described, with emphasis on the utilization of calorimetry

  13. Florence Jessie Mac Williams

    Indian Academy of Sciences (India)

    CPMGIKAlBGE-340/2003-05. Resonance - January 2005. Licenced to post WPP No.6 RT Nagar Postoffice. Florence Jessie Mac Williams. (1917 - 1990). Registered with Registrar of Newspapers in India vide Regn. No. 66273/96. ISSN 0971-8044. Price per copy: Rs 40.

  14. iMac pocket genius

    CERN Document Server

    Hart-Davis, Guy

    2010-01-01

    If you want to get the very most out of your iMac, put this savvy Portable Genius guide to work. Want to make the most of the new Magic Mouse and the latest iLife apps? Set up a wireless network using your iMac's AirPort card? Watch television on your iMac, or show iMac videos and movies on your television? You'll find cool and useful Genius tips, full-color screenshots, and pages of easy-to-access shortcuts and tools that will save you time and let you enjoy your iMac to the max.

  15. MacBook for dummies

    CERN Document Server

    Chambers , Mark L

    2014-01-01

    Make friends with your MacBook the fun and easy way! Ultra-light, ultra-fast, and ultra-powerful, the MacBook is the coolest laptop in town, and longtime Mac guru Mark L. Chambers is just the guy to help you get to know your MacBook in no time. Take a closer look at the latest features, get the lowdown on OS X, unleash your creative forces with iLife, take care of business with the iWork applications, and sync it all with iCloud with the expert advice in this bestselling MacBook guide. Whether this is your first MacBook or your first laptop, period, you''ll learn to navigate the Mac desktop, c

  16. Macs For Dummies, Pocket Edition

    CERN Document Server

    Baig, Edward C

    2011-01-01

    The fun and easy way to make the most of your wonderful Mac. Simply Mac-nificent — all the cool things your Mac can do! This handy guide helps you figure out the nuts and bolts of your Mac. Navigate the Mac desktop, use the Safari Web browser to surf the Internet, e-mail photos to friends and family, create and print documents, rip audio CDs, and more. The fun begins right here!. Open the book and find: How to set up and configure your Mac; Tips for getting around on the Mac desktop; Steps for setting up an e-mail account and browsing the Internet; Details about the free programs that come wit

  17. iMac portable genius

    CERN Document Server

    Hart-Davis, Guy

    2010-01-01

    The most up-to-date coverage on the latest iMac advice, tools, and shortcuts Cool and useful tips, full-color screenshots, and savvy advice show you how to get the most out of your iMac. Fully updated to cover the iMac's latest features and capabilities, this guide is packed with indispensible information on iLife '09 and Mac OS X Snow Leopard, and shows you how to customize your iMac in a way that it will work best for you.Explores all the bells and whistles of the iMac, including the new Magic Mouse, iLife apps such as iPhoto and iMovie, and Mac OS X Snow LeopardShows yo

  18. The effects of Poynting-Robertson drag on solar sails

    Science.gov (United States)

    Abd El-Salam, F. A.

    2018-06-01

    In the present work, the concept of solar sailing and its developing spacecraft are presented. The effects of Poynting-Robertson drag on solar sails are considered. Some analytical control laws with some mentioned input constraints for optimizing solar sails dynamics in heliocentric orbit using Lagrange's planetary equations are obtained. Optimum force vector in a required direction is maximized by deriving optimal sail cone angle. New control laws that maximize thrust to obtain certain required maximization in some particular orbital element are obtained.

  19. On the existence of perturbed Robertson-Walker universes

    International Nuclear Information System (INIS)

    D'Eath, P.D.

    1976-01-01

    Solutions of the full nonlinear field equations of general relativity near the Robertson-Walker universes are examined, together with their relation to linearized perturbations. A method due to Choquet-Bruhat and Deser is used to prove existence theorems for solutions near Robertson-Walker constraint data of the constraint equations on a spacelike hypersurface. These theorems allow one to regard the matter fluctuations as independent quantities, ranging over certain function spaces. In the k=-1 case the existence theory describes perturbations which may vary within uniform bounds throughout space. When k=+1 a modification of the method leads to a theorem which clarifies some unusual features of these constraint perturbations. The k=0 existence theorem refers only to perturbations which die away at large distances. The connection between linearized constraint solutions and solutions of the full constraints is discussed. For k= +- 1 backgrounds, solutions of the linearized constraints are analyzed using transverse-traceless decompositions of symmetric tensors. Finally the time-evolution of perturbed constraint data and the validity of linearized perturbation theory for Robertson-Walker universes are considered

  20. Inverse Argyll Robertson pupil in Burkitt′s lymphoma

    Directory of Open Access Journals (Sweden)

    Kakarla V Chalam

    2008-03-01

    Full Text Available Kakarla V Chalam, Shailesh K Gupta, Vikram S BrarDepartment of Ophthalmology, University of Florida Health Science Center, Jacksonville, FL, USAAbstract: We present a case of an 18 year old white male with Burkitt’s lymphoma who was operated on for hydrocephalus and subsequently referred for evaluation of new onset diplopia. On examination, his visual acuity (VA was 20/20 in both eyes with a right superior oblique palsy. His pupillary reaction to light was intact while on near gaze there was no constriction of the pupils, bilaterally. The other two responses of the near gaze triad ie, convergence and accommodation were present. These findings were suggestive of an Inverse Argyll Robertson pupil (IARP, a rare entity in the literature. We could not find a specific cause attributable to this manifestation in this patient, though we feel it may be secondary to infiltration from Burkitt’s lymphoma and/or compression from elevated intracranial pressure of the efferent pupillary near reflex pathway.Keywords: Inverse Argyll Robertson pupil, Argyll Robertson pupil, pupillary abnormalities, Burkitt’s lymphoma

  1. iMac for dummies

    CERN Document Server

    Chambers, Mark L

    2014-01-01

    Do it all with your iMac and this bestselling For Dummies guide! You're still a little giddy from finally scoring your new iMac, and you can't wait to get started. Even if you're already in love with your iMac, it helps to have a little guidance to really get the most out of this ultimate all-in-one computer. This updated edition of iMac For Dummies is the ideal way to learn the iMac fundamentals from setting up and personalizing your machine to importing files, making FaceTime video calls, surfing the web, using your favorite programs and apps, and everything in between. Trusted Mac guru Mark

  2. Learn Excel 2011 for Mac

    CERN Document Server

    Hart-Davis, Guy

    2011-01-01

    Microsoft Excel 2011 for Mac OS X is a powerful application, but many of its most impressive features can be difficult to find. Learn Excel 2011 for Mac by Guy Hart-Davis is a practical, hands-on approach to learning all of the details of Excel 2011 in order to get work done efficiently on Mac OS X. From using formulas and functions to creating databases, from analyzing data to automating tasks, you'll learn everything you need to know to put this powerful application to use for a variety of tasks. What you'll learn * The secrets of the Excel for Mac interface! * How to create effective workbo

  3. Anisotropic evolution of 5D Friedmann-Robertson-Walker spacetime

    International Nuclear Information System (INIS)

    Middleton, Chad A.; Stanley, Ethan

    2011-01-01

    We examine the time evolution of the five-dimensional Einstein field equations subjected to a flat, anisotropic Robertson-Walker metric, where the 3D and higher-dimensional scale factors are allowed to dynamically evolve at different rates. By adopting equations of state relating the 3D and higher-dimensional pressures to the density, we obtain an exact expression relating the higher-dimensional scale factor to a function of the 3D scale factor. This relation allows us to write the Friedmann-Robertson-Walker field equations exclusively in terms of the 3D scale factor, thus yielding a set of 4D effective Friedmann-Robertson-Walker field equations. We examine the effective field equations in the general case and obtain an exact expression relating a function of the 3D scale factor to the time. This expression involves a hypergeometric function and cannot, in general, be inverted to yield an analytical expression for the 3D scale factor as a function of time. When the hypergeometric function is expanded for small and large arguments, we obtain a generalized treatment of the dynamical compactification scenario of Mohammedi [Phys. Rev. D 65, 104018 (2002)] and the 5D vacuum solution of Chodos and Detweiler [Phys. Rev. D 21, 2167 (1980)], respectively. By expanding the hypergeometric function near a branch point, we obtain the perturbative solution for the 3D scale factor in the small time regime. This solution exhibits accelerated expansion, which, remarkably, is independent of the value of the 4D equation of state parameter w. This early-time epoch of accelerated expansion arises naturally out of the anisotropic evolution of 5D spacetime when the pressure in the extra dimension is negative and offers a possible alternative to scalar field inflationary theory.

  4. Public and private space curvature in Robertson-Walker universes.

    Science.gov (United States)

    Rindler, W.

    1981-05-01

    The question is asked: what space curvature would a fundamental observer in an ideal Robertson-Walker universe obtain by direct local spatial measurements, i.e., without reference to the motion pattern of the other galaxies? The answer is that he obtains the curvatureK of his “private” space generated by all the geodesics orthogonal to his world line at the moment in question, and that ˜K is related to the usual curvatureK=k/R 2 of the “public” space of galaxies byK=K+H 2/c2, whereH is Hubble's parameter.

  5. Mac Leod's syndrome

    International Nuclear Information System (INIS)

    Schad, M.; Danesi, C.; Ricci, R.; Galluzzi, S.; Coviello, G.

    1988-01-01

    Mac Leod's syndrome is a rarely diagnosed disease; that is why an accurate differential diagnosis is needed by means of radiological imaging. This paper is aimed at discussing the differential diagnosis, with a special emphasis on the pathogenesis of the syndrome. The phenomenon of air trapping in absence of central bronchial lesions is a typical radiographic finding. Chest X-ray is performed in both inspiration and expiration. Posterior oblique tomography at 55 grade centigrade of the effected side is also performed. Diffuse bronchiolitis obliterans in infancy or early childhood ia widely accepted pathogenetic pattern. Pulmonary hypoventilation causes vasoconstriction and underdevelopment of pulmonary vessels, that are reduced in caliber. Differential diagnosis includes all the diseases resulting in pulmonary hyperlucency, i.e. pulmonary and pleural alterations, and skeletal anomalies

  6. Windowsista Mac-maailmaan

    OpenAIRE

    Sirkiä, Noora-Maria

    2010-01-01

    Nykyään yhä useampi harkitsee erilaisista syistä käyttöjärjestelmän vaihtamista tutusta Windowsista johonkin muuhun käyttöjärjestelmään. Applen Macintosh-tietokoneiden mukana tuleva Mac OS X -käyttöjärjestelmä on hyvä vaihtoehto Windowsille. Ihmiset siirtyvät siihen mm. tietoturvaseikkojen, luotettavuuden, ohjelmiston sekä Applen koneiden ja käyttöjärjestelmän ulkomuodon takia. Microsoftin tuotteista ei myöskään tarvitse luopua kokonaan, sillä monista tutuista Microsoftin ohjelmista (esim. Mi...

  7. Generalized Friedmann-Robertson-Walker metric and redundancy in the generalized Einstein equations

    International Nuclear Information System (INIS)

    Kao, W.F.; Pen, U.

    1991-01-01

    A nontrivial redundancy relation, due to the differential structure of the gravitational Bianchi identity as well as the symmetry of the Friedmann-Robertson-Walker metric, in the gravitational field equation is clarified. A generalized Friedmann-Robertson-Walker metric is introduced in order to properly define a one-dimensional reduced problem which offers an alternative approach to obtain the gravitational field equations on Friedmann-Robertson-Walker spaces

  8. iMac for dummies

    CERN Document Server

    Chambers, Mark L

    2012-01-01

    The bestselling guide to the ultimate all-in-one computer—now updated and revised throughout! If you're looking for speed, performance, and power, the iMac is the ultimate all-in-one computer. From its superior performance, powerful operating system, and amazing applications, the iMac is one awesome machine, and the fun, friendly, and approachable style of iMac For Dummies is an ideal way to get started with the basics. You'll learn the fundamentals of the iMac including setting up and customizing your iMac and the software that comes with it, importing files from your old computer, send

  9. Lagrangian formulation of the general relativistic Poynting-Robertson effect

    Science.gov (United States)

    De Falco, Vittorio; Battista, Emmanuele; Falanga, Maurizio

    2018-04-01

    We propose the Lagrangian formulation for describing the motion of a test particle in a general relativistic, stationary, and axially symmetric spacetime. The test particle is also affected by a radiation field, modeled as a coherent flux of photons traveling along the null geodesics of the background spacetime, including the general relativistic Poynting-Robertson effect. The innovative part of this work is to prove the existence of the potential linked to the dissipative action caused by the Poynting-Robertson effect in general relativity through the help of an integrating factor, depending on the energy of the system. Generally, such kinds of inverse problems involving dissipative effects might not admit a Lagrangian formulation; especially, in general relativity, there are no examples of such attempts in the literature so far. We reduce this general relativistic Lagrangian formulation to the classic case in the weak-field limit. This approach facilitates further studies in improving the treatment of the radiation field, and it contains, for example, some implications for a deeper comprehension of the gravitational waves.

  10. Gotcha! Macs lose their innocence

    CERN Multimedia

    Computer Security Team

    2012-01-01

    Still believe your Mac is secure because Microsoft PCs fall prey to viruses and worms but Macs don’t? Time to wake up! This year has seen the first major compromise of Macs worldwide*. How is yours doing?   The “Flashback” Trojan is affecting Apple’s own variant of Java and compromises Macs via so-called drive-by infections, i.e. when you visit an appropriately prepared (infected!) website - and this might not necessarily be a site with questionable contents, but could well be a popular, reputable one. Security Companies worldwide have been monitoring this particular Trojan for a while and have estimated that more than half a million Macs were compromised. Connected to a few central command and control servers, the compromised Macs were then supporting the malicious activity of the bad guys! Fortunately, the security companies have now been able to take over those command and control servers and stop their destructive drive. So, Mac users, face the f...

  11. Java and Mac OS X

    CERN Document Server

    Davis, T Gene

    2010-01-01

    Learn the guidelines of integrating Java with native Mac OS X applications with this Devloper Reference book. Java is used to create nearly every type of application that exists and is one of the most required skills of employers seeking computer programmers. Java code and its libraries can be integrated with Mac OS X features, and this book shows you how to do just that. You'll learn to write Java programs on OS X and you'll even discover how to integrate them with the Cocoa APIs.: Shows how Java programs can be integrated with any Mac OS X feature, such as NSView widgets or screen savers; Re

  12. Robertson-Walker solutions for various types of energy-momentum tensor

    International Nuclear Information System (INIS)

    Lukacs, B.

    1976-01-01

    Robertson-Walker solutions are important in general relativity as universe solutions. This paper contains a number of Robertson-Walker-type solutions for certain cases, namely, for noncharged massless scalar meson fields, viscous fluids, Hookean elastic mediums, and Kelvin-Voigt viscoelastic systems. (author)

  13. Mac Programming for Absolute Beginners

    CERN Document Server

    Wang, Wallace

    2011-01-01

    Want to learn how to program on your Mac? Not sure where to begin? Best-selling author Wallace Wang will explain how to get started with Cocoa, Objective-C, and Xcode. Whether you are an experienced Windows coder moving to the Mac, or you are completely new to programming, you'll see how the basic design of a Mac OS X program works, how Objective-C differs from other languages you may have used, and how to use the Xcode development environment. Most importantly, you'll learn how to use elements of the Cocoa framework to create windows, store data, and respond to users in your own Mac programs.

  14. Alistair William MacDonald.

    Science.gov (United States)

    Callegari, Angus

    2018-01-06

    A devoted family man and churchgoer, Alistair MacDonald was a meticulous vet with a great sense of humour. Having served in the RAF during the Second World War, he had plenty of stories to tell. British Veterinary Association.

  15. Conformal Killing vectors in Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Maartens, R.; Maharaj, S.d.

    1986-01-01

    It is well known that Robertson-Walker spacetimes admit a conformal Killingl vector normal to the spacelike homogeneous hypersurfaces. Because these spacetimes are conformally flat, there are a further eight conformal Killing vectors, which are neither normal nor tangent to the homogeneous hypersurfaces. The authors find these further conformal Killing vectors and the Lie algebra of the full G 15 of conformal motions. Conditions on the metric scale factor are determined which reduce some of the conformal Killing vectors to homothetic Killing vectors or Killing vectors, allowing one to regain in a unified way the known special geometries. The non-normal conformal Killing vectors provide a counter-example to show that conformal motions do not, in general, map a fluid flow conformally. These non-normal vectors are also used to find the general solution of the null geodesic equation and photon Liouville equation. (author)

  16. Inverse curvature flows in asymptotically Robertson Walker spaces

    Science.gov (United States)

    Kröner, Heiko

    2018-04-01

    In this paper we consider inverse curvature flows in a Lorentzian manifold N which is the topological product of the real numbers with a closed Riemannian manifold and equipped with a Lorentzian metric having a future singularity so that N is asymptotically Robertson Walker. The flow speeds are future directed and given by 1 / F where F is a homogeneous degree one curvature function of class (K*) of the principal curvatures, i.e. the n-th root of the Gauss curvature. We prove longtime existence of these flows and that the flow hypersurfaces converge to smooth functions when they are rescaled with a proper factor which results from the asymptotics of the metric.

  17. Fiverr MacGyver

    Science.gov (United States)

    Hut, Rolf; van de Giesen, Nick; Larson, Martha

    2014-05-01

    Crowdsourcing has become popular over the past years, also for scientific endeavors. There are many Citizen Science projects and crowdfunding platforms, such as Kickstarter, that are make helpful contributions to moving environmental science forward. An interesting underused source of useful crowd-derived contributions to research is the website Fiverr.com. On this platform, thousands of people, acting as small-scale freelance contractors, offer their skills in the form of services. The platform offers a chance for people to take a hobby, skill, or pastime and make it something more by reaching out to a wider audience and by receiving a payment in return for services. As is typical of other crowdsourcing platforms, the tasks are small and usually self contained. As the name Fiverr suggests, offers start at US5 to provide a particular service. Services offered range from graphic design, to messages sung or spoken with various styles or accents, to complete apps for Android or iPhone. Skill providers on the platform can accept a range of variation of definition in the tasks, some can be described in general terms, for others it is more appropriate to provide examples. Fiverr provides a central location for those offering skills and those needing services to find each other, it makes it possible to communicate and exchange files, to make payments, and it provides support for resolving disputes. In all cases, it is important to keep expectations aligned with the nature of the platform: quality can and will vary. Ultimately, the critical contribution of Fiverr is not to replace professional services or otherwise save money, but rather to provide access to a large group of people with specialized skills who are able to make a contribution on short notice. In the context of this session, it can be considered a pool of people with MacGyver skills lying in wait of a MacGyyer task to attack. There are many ways in which Fiverr tasks, which are called 'gigs', can be useful in

  18. MacBook Teach Yourself VISUALLY

    CERN Document Server

    Miser, Brad

    2010-01-01

    Like the MacBook itself, Teach Yourself VISUALLY MacBook, Second Edition is designed to be visually appealing, while providing excellent functionality at the same time. By using this book, MacBook users will be empowered to do everyday tasks quickly and easily. From such basic steps as powering on or shutting down the MacBook, working on the Mac desktop with the Dashboard and its widgets to running Windows applications, Teach Yourself VISUALLY MacBook, Second Edition covers all the vital information and provides the help and support a reader needs—in many ways it's like having a Mac Genius at

  19. Land

    NARCIS (Netherlands)

    C.A. Hunsberger (Carol); Tom P. Evans

    2012-01-01

    textabstractPressure on land resources has increased during recent years despite international goals to improve their management. The fourth Global Environment Outlook (UNEP 2007) highlighted the unprecedented land-use changes created by a burgeoning population, economic development and

  20. Vacuum quantum effect for curved boundaries in static Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Setare, M.R.; Sadeghi, J.

    2009-01-01

    The energy-momentum tensor for a massless conformally coupled scalar field in the region between two curved boundaries in k=-1 static Robertson-Walker space-time is investigated. We assume that the scalar field satisfies the Dirichlet boundary condition on the boundaries. k=-1 Robertson-Walker space is conformally related to the Rindler space, as a result we can obtain vacuum expectation values of energy-momentum tensor for conformally invariant field in Robertson-Walker space from the corresponding Rindler counterpart by the conformal transformation.

  1. Mac OS X ja tietoturva

    OpenAIRE

    Herranen, Joni

    2011-01-01

    Tämän opinnäytetyön tavoitteena on luoda kattava kokonaiskuva Mac OS X -käyttöjärjestelmän sisäänrakennetuista tietoturvaratkaisuista ja selvittää miten tietoturvaratkaisut toteuttavat tietoturvan kolmea perustavoitetta eli luottamuksellisuutta, eheyttä ja saatavuutta. Työn kohderyhmäksi on valittu edistyneemmät tietokoneenkäyttäjät, joilla ei ole aikaisempaa Mac-kokemusta. Teoriaosuudessa syvennytään aluksi Apple-yhtiöön sekä Mac OS X -järjestelmän teknisiin ominaisuuksiin. Osuuden pääta...

  2. I-MAC: an incorporation MAC for wireless sensor networks

    Science.gov (United States)

    Zhao, Jumin; Li, Yikun; Li, Dengao; Lin, Xiaojie

    2017-11-01

    This paper proposes an innovative MAC protocol called I-MAC. Protocol for wireless sensor networks, which combines the advantages of collision tolerance and collision cancellation. The protocol increases the number of antenna in wireless sensor nodes. The purpose is to monitor the occurrence of packet collisions by increasing the number of antenna in real time. The built-in identity structure is used in the frame structure in order to help the sending node to identify the location of the receiving node after a data packet collision is detected. Packets can be recovered from where the conflict occurred. In this way, we can monitor the conflict for a fixed period of time. It can improve the channel utilisation through changing the transmission probability of collision nodes and solve the problem of hidden terminal through collision feedback mechanism. We have evaluated our protocol. Our results show that the throughput of I-MAC is 5 percentage points higher than that of carrier sense multiple access/collision notification. The network utilisation of I-MAC is more than 92%.

  3. E. Graeme Robertson--dynamics in fluid and light.

    Science.gov (United States)

    Kempster, P A; Gerraty, R P; Bower, S P C

    2013-02-01

    An eponymous lecture at the Australian and New Zealand Association of Neurologists Annual Scientific Meeting commemorates E. Graeme Robertson (1903-75), and some neurologists will know that particular Australian practices in clinical neurology, so far as they exist, have origins in his career. This is a historical article on the literary record of a man who had his own sense of history--an affinity with the past as well as an awareness of future generations of readers. He wrote authoritative texts on pneumoencephalography before new technology made it obsolete, and he produced a series of books on decorative architectural cast iron in Australian cities. A talent for visual interpretation seems to have drawn him to both of these topics; a common theme is contrast between light and dark, which is expatiated in images and in clear, well-written prose in his publications. We review his medical writings, including some largely forgotten principles of cerebrospinal fluid physics that he discovered when researching pneumoencephalography. We also explore his obsession with cast iron--its architectural historical significance, his techniques for photographing it, and some of the ways that it related to his life's work as a clinical neurologist. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. On the minimal vacuum definition for spin 1 massive fields in Robertson-Walker universes

    International Nuclear Information System (INIS)

    Castagnino, M.; Laciana, C.; Chimento, L.

    1986-01-01

    A definition of quantum vacuum is introduced for spin 1, massive, neutral fields, in spatially flat Robertson-Walker universes. For this definition all relevant observables turn out to be devoid of ultraviolet divergencies. (author)

  5. Spacetime emergence of the robertson-walker universe from a matrix model.

    Science.gov (United States)

    Erdmenger, Johanna; Meyer, René; Park, Jeong-Hyuck

    2007-06-29

    Using a novel, string theory-inspired formalism based on a Hamiltonian constraint, we obtain a conformal mechanical system for the spatially flat four-dimensional Robertson-Walker Universe. Depending on parameter choices, this system describes either a relativistic particle in the Robertson-Walker background or metric fluctuations of the Robertson-Walker geometry. Moreover, we derive a tree-level M theory matrix model in this time-dependent background. Imposing the Hamiltonian constraint forces the spacetime geometry to be fuzzy near the big bang, while the classical Robertson-Walker geometry emerges as the Universe expands. From our approach, we also derive the temperature of the Universe interpolating between the radiation and matter dominated eras.

  6. Mr MacDonald's suitcase

    DEFF Research Database (Denmark)

    2017-01-01

    Undervisningsforløbet Mr. MacDonald’s suitcase beskriver læringsmålstyret undervisning i faget engelsk i 1. klasse, hvor der arbejdes med kompetenceområdet mundtlig kommunikation. Undervisningsforløbet er bygget op omkring en engelsk tøjdukke, der besøger klassen og fortæller små historier...

  7. lands

    Directory of Open Access Journals (Sweden)

    A.T. O'Geen

    2015-04-01

    Full Text Available Groundwater pumping chronically exceeds natural recharge in many agricultural regions in California. A common method of recharging groundwater — when surface water is available — is to deliberately flood an open area, allowing water to percolate into an aquifer. However, open land suitable for this type of recharge is scarce. Flooding agricultural land during fallow or dormant periods has the potential to increase groundwater recharge substantially, but this approach has not been well studied. Using data on soils, topography and crop type, we developed a spatially explicit index of the suitability for groundwater recharge of land in all agricultural regions in California. We identified 3.6 million acres of agricultural land statewide as having Excellent or Good potential for groundwater recharge. The index provides preliminary guidance about the locations where groundwater recharge on agricultural land is likely to be feasible. A variety of institutional, infrastructure and other issues must also be addressed before this practice can be implemented widely.

  8. Mac OS X Lion Server For Dummies

    CERN Document Server

    Rizzo, John

    2011-01-01

    The perfect guide to help administrators set up Apple's Mac OS X Lion Server With the overwhelming popularity of the iPhone and iPad, more Macs are appearing in corporate settings. The newest version of Mac Server is the ideal way to administer a Mac network. This friendly guide explains to both Windows and Mac administrators how to set up and configure the server, including services such as iCal Server, Podcast Producer, Wiki Server, Spotlight Server, iChat Server, File Sharing, Mail Services, and support for iPhone and iPad. It explains how to secure, administer, and troubleshoot the networ

  9. Switching to the Mac The Missing Manual

    CERN Document Server

    Pogue, David

    2010-01-01

    Is Windows giving you pause? Ready to make the leap to the Mac instead? There has never been a better time to switch from Windows to Mac, and this incomparable guide will help you make a smooth transition. New York Times columnist and Missing Manuals creator David Pogue gets you past three challenges: transferring your stuff, assembling Mac programs so you can do what you did with Windows, and learning your way around Mac OS X. Learning to use a Mac is not a piece of cake, but once you do, the rewards are oh-so-much better. No viruses, worms, or spyware. No questionable firewalls, inefficien

  10. Switching to a Mac For Dummies

    CERN Document Server

    Reinhold, Arnold

    2007-01-01

    Thinking of making the switch from your PC to a Mac? Congratulations! You're in for a great, virus-free ride. And Switching to Mac For Dummies makes it smoother than you ever imagined. From buying the Mac that's right for you to transferring your files to breaking your old Windows habits and learning to do things the (much easier) Mac way, it makes the whole process practically effortless. Whether you've been using Windows XP, Vista, or even Linux, you'll find simple, straightforward ways to make your transition go smoothly. That will leave you plenty of time to get familiar with Mac'

  11. Cognitive MAC designs for OSA networks

    CERN Document Server

    Derakhshani, Mahsa

    2014-01-01

    This SpringerBrief presents recent advances in the cognitive MAC designs for opportunistic spectrum access (OSA) networks. It covers the basic MAC functionalities and MAC enhancements of IEEE 802.11. Later chapters discuss the existing MAC protocols for OSA and classify them based on characteristic features. The authors provide new research in adaptive carrier sensing-based MAC designs tailored for OSA, which optimize spectrum utilization and ensure a peaceful coexistence of licensed and unlicensed systems. Analytically devised via optimization and game-theoretic approaches, these adaptive M

  12. Mac OS X for Astronomy

    Science.gov (United States)

    Pierfederici, F.; Pirzkal, N.; Hook, R. N.

    Mac OS X is the new Unix based version of the Macintosh operating system. It combines a high performance DisplayPDF user interface with a standard BSD UNIX subsystem and provides users with simultaneous access to a broad range of applications which were not previously available on a single system such as Microsoft Office and Adobe Photoshop, as well as legacy X11-based scientific tools and packages like IRAF, SuperMongo, MIDAS, etc. The combination of a modern GUI layered on top of a familiar UNIX environment paves the way for new, more flexible and powerful astronomical tools to be developed while assuring compatibility with already existing, older programs. In this paper, we outline the strengths of the Mac OS X platform in a scientific environment, astronomy in particular, and point to the numerous astronomical software packages available for this platform; most notably the Scisoft collection which we have compiled.

  13. Technical Report : ContikiMAC vs X-MAC performance analysis

    OpenAIRE

    Michel, Mathieu; Quoitin, Bruno

    2014-01-01

    This paper try to better understand the performance of ContikiMAC compared to X-MAC. ContikiMAC achieves a transmission by repeatedly transmitting a data packet until the reception of an ACK from the destination. While X-MAC uses a stream of small size strobes to advertise the destination of the incoming transmission. A priori, X-MAC is then less bandwidth consumptive. To better understand the efficiency of ContikiMAC, despite an intuitively more consumptive transmitting procedure, we have co...

  14. Land

    CSIR Research Space (South Africa)

    Audouin, M

    2007-01-01

    Full Text Available the factors contributing to desertification and practical measures necessary to combat desertification and mitigate the effect of drought. The priority issues reported on in this chapter are soil and veld degradation, and the loss of land for agricultural use....

  15. Teach yourself visually Mac Mini

    CERN Document Server

    Hart-Davis, Guy

    2012-01-01

    The perfect how-to guide for visual learners Apple?s Mac Mini packs a powerful punch is in a small package, including both HDMI and Thunderbolt ports plus the acclaimed OS X. But if you want to get the very most from all this power and versatility, be sure to get this practical visual guide. With full-color, step-by-step instructions as well as screenshots and illustrations on every page, it clearly shows you how to accomplish tasks rather than burying you in pages of text. Discover helpful visuals and how-tos on the OS, hardware specs, Launchpad, the App Store, multimedia capabilities (such

  16. Web Development with the Mac

    CERN Document Server

    Vegh, Aaron

    2010-01-01

    Learn Web development the Apple way and build a business. With a focus on both coding and creative development, this in-depth guide thoroughly covers what you need to know to build winning websites for clients — from what it takes to bring a business online to how to make your site interactive to how to run a freelance web business. In between, you'll master the technical tools of the trade — such as HTML, CSS, JavaScript, PHP, and Ruby on Rails — and learn how to create beautiful interfaces using Photoshop . This book covers everything a fledgling web developer working on a Mac needs to launc

  17. Revised Robertson's test theory of special relativity: space-time structure and dynamics

    International Nuclear Information System (INIS)

    Vargas, J.G.; Torr, D.G.

    1986-01-01

    The experimental testing of the Lorentz transformations is based on a family of sets of coordinate transformations that do not comply in general with the principle of equivalence of the inertial frames. The Lorentz and Galilean sets of transformations are the only member sets of the family that satisfy this principle. In the neighborhood of regular points of space-time, all members in the family are assumed to comply with local homogeneity of space-time and isotropy of space in at least one free-falling elevator, to be denoted as Robertson's ab initio rest frame (H.P. Robertson, Rev. Mod. Phys. 21, 378 (1949)). Without any further assumptions, it is shown that Robertson's rest frame becomes a preferred frame for all member sets of the Robertson family except for, again, Galilean and Einstein's relativities. If one now assumes the validity of Maxwell-Lorentz electrodynamics in the preferred frame, a different electrodynamics spontaneously emerges for each set of transformations. The flat space-time of relativity retains its relevance, which permits an obvious generalization, in a Robertson context, of Dirac's theory of the electron and Einstein's gravitation. The family of theories thus obtained constitutes a covering theory of relativistic physics. A technique is developed to move back and forth between Einstein's relativity and the different members of the family of theories. It permits great simplifications in the analysis of relativistic experiments with relevant ''Robertson's subfamilies.'' It is shown how to adapt the Clifford algebra version of standard physics for use with the covering theory and, in particular, with the covering Dirac theory

  18. Mac OS X Tiger for Unix Geeks

    CERN Document Server

    Jepson, Brian

    2005-01-01

    If you're one of the many Unix developers drawn to Mac OS X for its Unix core, you'll find yourself in surprisingly unfamiliar territory. Unix and Mac OS X are kissing cousins, but there are enough pitfalls and minefields in going from one to another that even a Unix guru can stumble, and most guides to Mac OS X are written for Mac aficionados. For a Unix developer, approaching Tiger from the Mac side is a bit like learning Russian by reading the Russian side of a Russian-English dictionary. Fortunately, O'Reilly has been the Unix authority for over 25 years, and in Mac OS X Tiger for Unix Gee

  19. Galilean generalized Robertson-Walker spacetimes: A new family of Galilean geometrical models

    Science.gov (United States)

    de la Fuente, Daniel; Rubio, Rafael M.

    2018-02-01

    We introduce a new family of Galilean spacetimes, the Galilean generalized Robertson-Walker spacetimes. This new family is relevant in the context of a generalized Newton-Cartan theory. We study its geometrical structure and analyse the completeness of its inextensible free falling observers. This sort of spacetimes constitutes the local geometric model of a much wider family of spacetimes admitting certain conformal symmetry. Moreover, we find some sufficient geometric conditions which guarantee a global splitting of a Galilean spacetime as a Galilean generalized Robertson-Walker spacetime.

  20. Take control the Mac OS X lexicon

    CERN Document Server

    Zardetto, Sharon

    2009-01-01

    This ebook explains a little bit of everything; in fact, it's The Mac OS X (and then some) Lexicon because it's never just you and your Mac. It's you and your Mac and the Web, and your email, and that article you just read that threw 17 new acronyms at you or assumed that you knew all sorts of networking terms. Or it's you and your Mac and Finder features you've never touched, such as burn folders, smart folders, or proxy icons, and that mysterious Services submenu. This book is a great guide for Macintosh users everywhere who have trouble keeping up with the latest jargon, fo

  1. Mac protocols for cyber-physical systems

    CERN Document Server

    Xia, Feng

    2015-01-01

    This book provides a literature review of various wireless MAC protocols and techniques for achieving real-time and reliable communications in the context of cyber-physical systems (CPS). The evaluation analysis of IEEE 802.15.4 for CPS therein will give insights into configuration and optimization of critical design parameters of MAC protocols. In addition, this book also presents the design and evaluation of an adaptive MAC protocol for medical CPS, which exemplifies how to facilitate real-time and reliable communications in CPS by exploiting IEEE 802.15.4 based MAC protocols. This book wil

  2. Macs all-in-one for dummies

    CERN Document Server

    Hutsko, Joe

    2014-01-01

    Your all-in-one guide to unleashing your Mac's full potential It's a Mac world out there. But if you haven't read the instruction manual, you may be neglecting some of your computer's coolest features. Turn to Macs All-in-One For Dummies' jam-packed guide to access the incredible tools within your computer. With this fully updated reference, you will learn how to use Launchpad and Mission Control; protect your Mac; back up and restore data with Time Machine; sync across devices in iCloud; import, organize, and share photos; direct in iMovie; compose in GarageBand; and so much more. The possi

  3. Douglas MacArthur Upon Reflection

    National Research Council Canada - National Science Library

    Snitchler, Lowell

    1998-01-01

    .... This research recounts MacArthur's personality development from childhood, investigates his last military campaign, and, finally, applies the diagnosis of narcissistic personality disorder to the assembled data...

  4. Quicksilver Power Mac G4

    CERN Document Server

    2001-01-01

    A new generation with a reworked motherboard is launched on 2001 with however the same Graphite box. It also included a processor speed-bump, and brought the DVD-R "SuperDrive" to the mid-level model. The Quicksilver PowerMac was available in three configurations: The 733 MHz model, with 128 MB of RAM, a 40 GB hard drive, and a CD-RW drive, was 1,699 dollars, the 867 MHz configuration, with 128 MB of RAM, a 60 GB hard drive and a DVD-R drive, was 2,499 dollars, and the high-end dual-800 MHz model, with 256 MB of RAM, an 80 GB hard drive and a DVD-R drive, was 3,499 dollars. The 733 MHz model is the first personal computer to have a DVD burner, named SuperDrive at Apple. The design was updated on 2002 with 800 MHz, 933 MHz and dual 1 GHz configurations, becoming the first Mac to reach 1 GHz.

  5. 78 FR 23843 - Special Local Regulations; Moss Point Rockin' the Riverfront Festival; Robertson Lake & O'Leary...

    Science.gov (United States)

    2013-04-23

    ...-AA08 Special Local Regulations; Moss Point Rockin' the Riverfront Festival; Robertson Lake & O'Leary... Festival high speed boat races. Entry into, transiting or anchoring in this area is prohibited to all... Rockin' the Riverfront Festival; Robertson Lake & O'Leary Lake; Moss Point, MS. (a) Location. The...

  6. 78 FR 9866 - Special Local Regulation; Moss Point Rockin' the Riverfront Festival; Robertson Lake & O'Leary...

    Science.gov (United States)

    2013-02-12

    ... 1625-AA08 Special Local Regulation; Moss Point Rockin' the Riverfront Festival; Robertson Lake & O... Riverfront Festival high speed boat races. Entry into, transiting or anchoring in this area is prohibited to... Point Rockin' the Riverfront Festival; Robertson Lake & O'Leary Lake; Moss Point, MS. (a) Location. The...

  7. Analysis of 3gpp-MAC and two-key 3gpp-MAC

    DEFF Research Database (Denmark)

    Knudsen, Lars Ramkilde; Mitchell, C.J.

    2003-01-01

    Forgery and key-recovery attacks are described on the 3gpp-MAC scheme, proposed for inclusion in the 3gpp specification. Three main classes of attack are given, all of which operate whether or not truncation is applied to the MAC value. Attacks in the first class use a large number of 'chosen MAC...

  8. Green's functions for a scalar fields in a class of Robertson-Walker space-times

    International Nuclear Information System (INIS)

    Mankin, Romi; Ainsaar, Ain

    1997-01-01

    The retarded and advanced Green's functions for a massless non conformally-coupled scalar field in a class of Robertson-Walker space-times are calculated analytically. The results are applied to the calculation of the Hadamard fundamental solutions in some special cases. (author)

  9. On Maximal Surfaces in Certain Non-Flat 3-Dimensional Robertson-Walker Spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Alfonso, E-mail: aromero@ugr.es [Universidad de Granada, Departamento de Geometria y Topologia (Spain); Rubio, Rafael M., E-mail: rmrubio@uco.es [Universidad de Cordoba, Departamento de Matematicas, Campus de Rabanales (Spain)

    2012-09-15

    An upper bound for the integral, on a geodesic disc, of the squared length of the gradient of a distinguished function on any maximal surface in certain non-flat 3-dimensional Robertson-Walker spacetimes is obtained. As an application, a new proof of a known Calabi-Bernstein's theorem is given.

  10. Spacelike Hypersurfaces in Weighted Generalized Robertson-Walker Space-Times

    Directory of Open Access Journals (Sweden)

    Ximin Liu

    2018-01-01

    Full Text Available Applying generalized maximum principle and weak maximum principle, we obtain several uniqueness results for spacelike hypersurfaces immersed in a weighted generalized Robertson-Walker (GRW space-time under suitable geometric assumptions. Furthermore, we also study the special case when the ambient space is static and provide some results by using Bochner’s formula.

  11. George MacDonald's Estimate of Childhood

    Science.gov (United States)

    Pridmore, John

    2007-01-01

    The nineteenth-century fantasy writer George MacDonald believed that "it is better to be a child in a green field than a knight of many orders." In this paper, I shall explore the bearing of this high estimate of childhood on spiritual education. MacDonald explores the spirituality of the child in his essay "A Sketch of Individual Development" and…

  12. Comments on the article "Changing attitudes towards the care of children in hospital: a new assessment of the influence of the work of Bowlby and Robertson in the UK, 1940-1970" by Frank C.P. van der Horst and Rene van der Veer (Attachment and Human Development Vol 11, No 2, March 2009, 119-142).

    Science.gov (United States)

    Lindsay, Mary

    2009-11-01

    The authors give an impressive list of references, but these do not reflect the situation in the UK; most of those looking after children in hospital did not write about what they did or read about what others did. Children in hospital saw little or nothing of their parents, and once they had 'settled' the doctors and nurses were unaware of their distress. John Bowlby's interest in maternal deprivation led him to appoint James Robertson as his research assistant, to observe responses of young children to loss of maternal care on admission to hospital. They formulated the theoretical framework of the three stages through which the children went; protest, despair, and detachment constituting a developmental interference. Robertson was so concerned when nobody would listen that in 1952 he made the film 'A Two Year Old Goes to Hospital', which upset children's doctors and nurses. It also probably contributed to the government setting up in 1957 a Committee chaired by Sir Harry Platt to consider the Welfare of Children in Hospital. 'Going to Hospital with Mother' was made by Robertson in 1958. With Dermod MacCarthy he showed the films to the Committee, who accepted the suggestions in Robertson's Memorandum which included unrestricted visiting and mothers being admitted with their young children. The Report, known as the Platt Report, was published in 1959. Robertson could then show his films publicly, campaign in the media and encourage the pressure group NAWCH (the National Association for the Welfare of Children in Hospital) who were successful in getting many of the Committee's recommendations implemented, to the benefit of all children in hospital.

  13. Mac OS X for Unix Geeks (Leopard)

    CERN Document Server

    Rothman, Ernest E; Rosen, Rich

    2009-01-01

    If you've been lured to Mac OS X because of its Unix roots, this invaluable book serves as a bridge between Apple's Darwin OS and the more traditional Unix systems. The new edition offers a complete tour of Mac OS X's Unix shell for Leopard and Tiger, and helps you find the facilities that replace or correspond to standard Unix utilities. Learn how to compile code, link to libraries, and port Unix software to Mac OS X and much more with this concise guide.

  14. Office 2008 for Mac for dummies

    CERN Document Server

    LeVitus, Bob

    2013-01-01

    Office 2008 for Mac is here, with great new enhancements to all your favorite office productivity tools. Who better than "Dr. Mac, "Bob LeVitus, to show you how to load and use them all? From choosing the best version for your needs to managing your life with your online calendar, Office 2008 For Mac For Dummies covers what you need to know. It compares the Student/Teacher Edition, Standard Edition, and Professional Edition, then walks you through installing your preferred version and keeping it up to date. You'll find out all the things you can do with Word, Excel, PowerPoint, and Entourage,

  15. Learn Office 2011 for Mac OS X

    CERN Document Server

    Hart-Davis, Guy

    2011-01-01

    Office for Mac remains the leading productivity suite for Mac, with Apple's iWork and the free OpenOffice.org trailing far behind. And now it's being updated with a cleaner interface and more compatibility with Exchange and SharePoint. Learn Office 2011 for Mac OS X offers a practical, hands-on approach to using Office 2011 applications to create and edit documents and get work done efficiently. You'll learn how to customize Office, design, create, and share documents, manipulate data in a spreadsheet, and create lively presentations. You'll also discover how to organize your email, contacts,

  16. Separation of massive field equation of arbitrary spin in Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Zecca, A.

    2006-01-01

    The massive spin-(3/2) field equation is explicitly integrated in the Robertson-Walker space-time by the Newman Penrose formalism. The solution is obtained by extending a separation procedure previously used to solve the spin-1 equation. The separated time dependence results in two coupled equations depending on the cosmological background evolution. The separated angular equations are explicitly integrated and the eigenvalues determined. The separated radial equations are integrated in the flat space-time case. The separation method of solution is then generalized, by induction, to prove the main result, that is the separability of the massive field equations of arbitrary spin in the Robertson-Walker space-time

  17. Massive bosons interacting with gravity: No standard solutions in Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Zecca, A.

    2009-01-01

    The problem of the interaction of boson and gravitational field is formulated in the Robertson-Walker space-time. It consist the simultaneous solution of the boson and of the Einstein field equation whose source is the energy momentum tensor of the boson field. By direct verification it is shown that the problem does not admit solutions in the class of massive standard solutions, previously determined, of the boson field equation. Also there cannot be solutions, in case of massive interacting boson, that are superpositions of standard solutions. The case of massless boson field is left open. The result is essentially due to the very special form of the Einstein tensor in Robertson-Walker metric.

  18. MACS as a tool for international inspections

    International Nuclear Information System (INIS)

    Curtiss, J.A.; Indusi, J.P.

    1995-01-01

    The MACS/ACRS (Managed Access by Controlled Sensing/Access by Controlled Remote Sensing) system is a collection of communication devices, video capability, and distance-measuring equipment which can effectively substitute for the physical presence of a challenge inspector within a facility. The MACS design allows growth of the prototype, developed in response to the Chemical Weapons Convention (CWC), into a versatile device for inspection of sensitive nuclear facilities under other international arrangements, for example the proposed Fissile Material Cutoff Convention. A MACS/ACRS-type system in a standard, international-recognized configuration could resolve sensitive information and safety concerns through providing a means of achieving the goals of an inspection while excluding the inspector. We believe the technology used to develop MACS for the Defense Nuclear Agency, followed by ACRS for the Department of Energy, is universally adaptable for minimally-intrusive managed-access international inspections of sensitive sites

  19. MACS as a tool for international inspections

    Energy Technology Data Exchange (ETDEWEB)

    Curtiss, J.A.; Indusi, J.P.

    1995-08-01

    The MACS/ACRS (Managed Access by Controlled Sensing/Access by Controlled Remote Sensing) system is a collection of communication devices, video capability, and distance-measuring equipment which can effectively substitute for the physical presence of a challenge inspector within a facility. The MACS design allows growth of the prototype, developed in response to the Chemical Weapons Convention (CWC), into a versatile device for inspection of sensitive nuclear facilities under other international arrangements, for example the proposed Fissile Material Cutoff Convention. A MACS/ACRS-type system in a standard, international-recognized configuration could resolve sensitive information and safety concerns through providing a means of achieving the goals of an inspection while excluding the inspector. We believe the technology used to develop MACS for the Defense Nuclear Agency, followed by ACRS for the Department of Energy, is universally adaptable for minimally-intrusive managed-access international inspections of sensitive sites.

  20. Learn Mac OS X Snow Leopard

    CERN Document Server

    Meyers, Scott

    2009-01-01

    You're smart and savvy, but also busy. This comprehensive guide to Apple's Mac OS X 10.6, Snow Leopard, gives you everything you need to know to live a happy, productive Mac life. Learn Mac OS X Snow Leopard will have you up and connected lickity split. With a minimum of overhead and a maximum of useful information, you'll cover a lot of ground in the time it takes other books to get you plugged in. If this isn't your first experience with Mac OS X, skip right to the "What's New in Snow Leopard" sections. You may also find yourself using this book as a quick refresher course or a way

  1. MAC reduction of isoflurane by sufentanil.

    Science.gov (United States)

    Brunner, M D; Braithwaite, P; Jhaveri, R; McEwan, A I; Goodman, D K; Smith, L R; Glass, P S

    1994-01-01

    We have shown previously that a plasma fentanyl concentration of 1.67 ng ml-1 reduced the MAC of isoflurane by 50%. By comparing equal degrees of MAC reduction by sufentanil, we may determine the potency ratio of these opioids. Seventy-six patients were allocated randomly to receive predetermined infusions of sufentanil, and end-tidal concentrations of isoflurane in oxygen. Blood samples were obtained 10 min after the start of the infusion, and just before and after skin incision. Any purposeful movement by the patient was recorded. The MAC reduction of isoflurane produced by sufentanil was obtained using a logistic regression model. A sufentanil plasma concentration of 0.145 ng ml-1 (95% confidence limits 0.04, 0.26 ng ml-1) resulted in a 50% reduction in the MAC of isoflurane. At a plasma concentration greater than 0.5 ng ml-1, sufentanil exhibited a ceiling effect.

  2. Quantum field theory in flat Robertson-Walker space-time functional Schrodinger picture

    International Nuclear Information System (INIS)

    Pi, S.Y.

    1990-01-01

    Quantum field theory in Robertson-Walker space-time is intrinsically time-dependent and the functional Schrodinger picture provides a useful description. This paper discusses free and self-interacting bosonic quantum field theories: Schrodinger picture quantization, time-dependent Gaussian approximations based on variational principles describing time evolution of pure and mixed states, and renormalizability of the Schrodinger picture. The technique introduced can be used to study various dynamical questions in early universe processes

  3. Reciprocal classes of p-valently spirallike and p-valently Robertson functions

    Directory of Open Access Journals (Sweden)

    Shiraishi Hitoshi

    2011-01-01

    Full Text Available Abstract For p-valently spirallike and p-valently Robertson functions in the open unit disk U , reciprocal classes S p ( α , β , and C p ( α , β are introduced. The object of the present paper is to discuss some interesting properties for functions f(z belonging to the classes Sp(α,β and Cp(α,β . 2010 Mathematics Subject Classification Primary 30C45

  4. Solutions to the maximal spacelike hypersurface equation in generalized Robertson-Walker spacetimes

    Directory of Open Access Journals (Sweden)

    Henrique F. de Lima

    2018-03-01

    Full Text Available We apply some generalized maximum principles for establishing uniqueness and nonexistence results concerning maximal spacelike hypersurfaces immersed in a generalized Robertson-Walker (GRW spacetime, which is supposed to obey the so-called timelike convergence condition (TCC. As application, we study the uniqueness and nonexistence of entire solutions of a suitable maximal spacelike hypersurface equation in GRW spacetimes obeying the TCC.

  5. Quantum field theory in flat Robertson-Walker space-time functional Schroedinger picture

    International Nuclear Information System (INIS)

    Pi, S.Y.

    1989-01-01

    Quantum field theory in Robertson-Walker space-time is intrinsically time-dependent and the functional Schroedinger picture provides a useful description. We discuss free and self-interacting bosonic quantum field theories: Schroedinger picture quantization, time-dependent Gaussian approximations based on variational principles describing time evolution of pure and mixed states, and renormalizability of the Schroedinger picture. The techniques introduced can be used to study various dynamical questions in early universe processes. (author)

  6. Macintosh Troubleshooting Pocket Guide for Mac OS

    CERN Document Server

    Lerner, David; Corporation, Tekserve

    2009-01-01

    The Macintosh Troubleshooting Pocket Guide covers the most common user hardware and software trouble. It's not just a book for Mac OS X (although it includes tips for OS X and Jaguar), it's for anyone who owns a Mac of any type-- there are software tips going back as far as OS 6. This slim guide distills the answers to the urgent questions that Tekserve's employee's answer every week into a handy guide that fits in your back pocket or alongside your keyboard.

  7. Enhanced Sleep Mode MAC Control for EPON

    DEFF Research Database (Denmark)

    Yan, Ying; Dittmann, Lars

    2011-01-01

    This paper introduces sleep mode operations for EPON. New MAC control functions are proposed to schedule sleep periods. Traffic profiles are considered to optimize energy efficiency and network performances. Simulation results are analyzed in OPNET modeler.......This paper introduces sleep mode operations for EPON. New MAC control functions are proposed to schedule sleep periods. Traffic profiles are considered to optimize energy efficiency and network performances. Simulation results are analyzed in OPNET modeler....

  8. Wound Healing in Mac-1 Deficient Mice

    Science.gov (United States)

    2017-05-01

    Dentistry, University of Illinois at Chicago, Chicago, IL, USA. 2 Department of Defense Biotechnology High Performance Computing Software...study, we used a commercially available Mac-1 deficient strain to examine whether this deficit 5 extends to slightly smaller wounds and incisional...levels of Collagen I and Collagen III in wounds from the two strains of mice at any time point. Unwounded skin from both WT and Mac-1 -/- mice contained

  9. AeroMACS system characterization and demonstrations

    Science.gov (United States)

    Kerczewski, R. J.; Apaza, R. D.; Dimond, R. P.

    This The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past three years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

  10. The Dirac equation and the normalization of its solutions in a closed Friedmann- Robertson-Walker universe

    Energy Technology Data Exchange (ETDEWEB)

    Finster, Felix [NWF I-Mathematik, Universitaet Regensburg, D-93040 Regensburg (Germany); Reintjes, Moritz, E-mail: Felix.Finster@mathematik.uni-regensburg.d, E-mail: moritz@math.ucdavis.ed [Mathematics Department, University of California, Davis, CA 95616 (United States)

    2009-05-21

    We set up the Dirac equation in a Friedmann-Robertson-Walker geometry and separate the spatial and time variables. In the case of a closed universe, the spatial dependence is solved explicitly, giving rise to a discrete set of solutions. We compute the probability integral and analyze a spacetime normalization integral. This analysis allows us to introduce the fermionic projector in a closed Friedmann-Robertson-Walker geometry and to specify its global normalization as well as its local form.

  11. The Dirac equation and the normalization of its solutions in a closed Friedmann- Robertson-Walker universe

    International Nuclear Information System (INIS)

    Finster, Felix; Reintjes, Moritz

    2009-01-01

    We set up the Dirac equation in a Friedmann-Robertson-Walker geometry and separate the spatial and time variables. In the case of a closed universe, the spatial dependence is solved explicitly, giving rise to a discrete set of solutions. We compute the probability integral and analyze a spacetime normalization integral. This analysis allows us to introduce the fermionic projector in a closed Friedmann-Robertson-Walker geometry and to specify its global normalization as well as its local form.

  12. Mac protocols for wireless sensor network (wsn): a comparative study

    International Nuclear Information System (INIS)

    Arshad, J.; Akram, Q.; Saleem, Y.

    2014-01-01

    Data communication between nodes is carried out under Medium Access Control (MAC) protocol which is defined at data link layer. The MAC protocols are responsible to communicate and coordinate between nodes according to the defined standards in WSN (Wireless Sensor Networks). The design of a MAC protocol should also address the issues of energy efficiency and transmission efficiency. There are number of MAC protocols that exist in the literature proposed for WSN. In this paper, nine MAC protocols which includes S-MAC, T-MAC, Wise-MAC, Mu-MAC, Z-MAC, A-MAC, D-MAC, B-MAC and B-MAC+ for WSN have been explored, studied and analyzed. These nine protocols are classified in contention based and hybrid (combination of contention and schedule based) MAC protocols. The goal of this comparative study is to provide a basis for MAC protocols and to highlight different mechanisms used with respect to parameters for the evaluation of energy and transmission efficiency in WSN. This study also aims to give reader a better understanding of the concepts, processes and flow of information used in these MAC protocols for WSN. A comparison with respect to energy reservation scheme, idle listening avoidance, latency, fairness, data synchronization, and throughput maximization has been presented. It was analyzed that contention based MAC protocols are less energy efficient as compared to hybrid MAC protocols. From the analysis of contention based MAC protocols in term of energy consumption, it was being observed that protocols based on preamble sampling consume lesser energy than protocols based on static or dynamic sleep schedule. (author)

  13. MacSelfService online tutorial

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    Mac Self-Service is a functionality within the Mac Desktop Service built and maintained to empower CERN users by giving them easy access to applications and configurations through the Self-Service application. This tutorial (text attached to the event page) explains how to install Mac Self-Service and how to use it to install applications and printers. Content owner: Vincent Nicolas Bippus Presenter: Pedro Augusto de Freitas Batista Tell us what you think via e-learning.support at cern.ch More tutorials in the e-learning collection of the CERN Document Server (CDS) https://cds.cern.ch/collection/E-learning%20modules?ln=en All info about the CERN rapid e-learning project is linked from http://twiki.cern.ch/ELearning  

  14. MacBook Pro Portable Genius

    CERN Document Server

    Miser, Brad

    2011-01-01

    Tips and techniques for forward-thinking MacBook Pro users Now that you have a MacBook Pro, you need just one more accessory, your very own copy of MacBook Pro Portable Genius, Third Edition. This handy, compact book lets you in on a wealth of tips and tricks, so you get the very most out of Apple's very popular notebook. Discover the latest on the most recent release of iLife, get the skinny on the new Intel Core i7 and i5 processors in the Pro, see how to go wireless in a smart way, and much more. The book is easy to navigate, doesn't skimp on the essentials, and helps you save time and avoi

  15. A MAC Mode for Lightweight Block Ciphers

    DEFF Research Database (Denmark)

    Luykx, Atul; Preneel, Bart; Tischhauser, Elmar Wolfgang

    2016-01-01

    Lightweight cryptography strives to protect communication in constrained environments without sacrificing security. However, security often conflicts with efficiency, shown by the fact that many new lightweight block cipher designs have block sizes as low as 64 or 32 bits. Such low block sizes lead...... no effect on the security bound, allowing an order of magnitude more data to be processed per key. Furthermore, LightMAC is incredibly simple, has almost no overhead over the block cipher, and is parallelizable. As a result, LightMAC not only offers compact authentication for resource-constrained platforms...

  16. Douglas MacArthur- An Administrative Biography

    OpenAIRE

    Tehan III, William J.

    2002-01-01

    For more than a half century Douglas MacArthur was a servant of the United States. He is best remembered as a general and a soldier, especially for his leadership during World War II and the Korean War. MacArthur was also the Superintendent of West Point, Chief of Staff of the U.S. Army, Generalissimo ( Commander) of the Armed Forces and Military Advisor (Minister of Defense) to the President of the Commonwealth of the Philippines, and the Supreme Commander Allied Powers and the Military Gove...

  17. MacBook Pro Portable Genius

    CERN Document Server

    Miser, Brad

    2012-01-01

    Discover loads of tips and techniques for the newest MacBook Pro You're already ahead of the game with a MacBook Pro. Now you can get even more out the popular Apple notebook with the new edition of this handy, compact book. Crammed with savvy insights and tips on key tools and shortcuts, this book will help you increase your productivity and keep your Apple digital lifestyle on track. From desktop sharing and wireless networking to running Windows applications, this book avoids fluff, doesn't skimp on the essentials, saves you time and hassle, and shows you what you most want to know. Include

  18. Mac OS X Snow Leopard pocket guide

    CERN Document Server

    Seiblod, Chris

    2009-01-01

    Whether you're new to the Mac or a longtime user, this handy book is the quickest way to get up to speed on Snow Leopard. Packed with concise information in an easy-to-read format, Mac OS X Snow Leopard Pocket Guide covers what you need to know and is an ideal resource for problem-solving on the fly. This book goes right to the heart of Snow Leopard, with details on system preferences, built-in applications, and utilities. You'll also find configuration tips, keyboard shortcuts, guides for troubleshooting, lots of step-by-step instructions, and more. Learn about new features and changes s

  19. On the spectrum of particles created in a Robertson-Walker universe

    International Nuclear Information System (INIS)

    Azuma, T.

    1983-01-01

    Created particle spectra are calculated in Robertson-Walker universes and discussed with a special emphasis on their dependence upon the initial and final times at which a WKB-like positive frequency conditions should be imposed. It is shown that the obtained spectra are very sensitive to these times if the WKB approximation for the field equation is not valid in their neighborhood. It is also shown that the total number density of created particles remains finite if the final time is set to be finite. (author)

  20. Finite-temperature effects in the φ4-model in a Robertson-Walker universe

    International Nuclear Information System (INIS)

    Kundu, P.K.

    1987-01-01

    The computation of the one-loop trace anomaly in a massless, conformally coupled φ 4 -model displaying spontaneous symmetry breaking in a spatially flat Robertson-Walker universe investigated in a previous paper, is extended to the case in which the physical system is in a state of thermal equilibrium. It is found that due to a nonperturbative nature of this effect the anomalous trace exhibits a rather nontrivial temperature dependence and cannot be expressed as a sum of contributions from the vacuum state and an ideal black-body radiation gas

  1. Energy-momentum tensor and definition of particle states for Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Brown, M.R.; Dutton, C.R.

    1978-01-01

    A new regularization scheme is developed for calculating expectation values of the energy-momentum tensor of a quantized scalar field in Robertson-Walker space-times. Using this regularized stress tensor we consider a definition for the vacuum state of the scalar field on any initial hypersurface. Asymptotic methods are developed to investigate the structure of both the divergent and finite terms of the stress tensor when evaluated in this state. The conformal anomaly is discussed in the context of this model. It does not naturally enter into the analysis and we argue that its inclusion is unnecessary

  2. Lanczos potentials and a definition of gravitational entropy for perturbed Friedman-Lemaitre-Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Mena, Filipe C; Tod, Paul

    2007-01-01

    We give a prescription for constructing a Lanczos potential for a cosmological model which is a purely gravitational perturbation of a Friedman-Lemaitre-Robertson-Walker spacetime. For the radiation equation of state, we find the Lanczos potential explicitly via Fourier transforms. As an application, we follow up a suggestion of Penrose (1979 Singularities and time-asymmetry General Relativity: An Einstein Centenary Survey ed S W Hawking and W Israel (Cambridge: Cambridge University Press)) and propose a definition of gravitational entropy for these cosmologies. With this definition, the gravitational entropy initially is finite if and only if the initial Weyl tensor is finite

  3. Results from the MAC Vertex chamber

    International Nuclear Information System (INIS)

    Nelson, H.N.

    1987-05-01

    The design, construction, and performance characteristics of a high precision gaseous drift chamber made of thin walled proportional tubes are described. The device achieved an average spatial resolution of 45 μm in use for physics analysis with the MAC detector. The B-lifetime result obtained with this chamber is discussed

  4. The Big Mac Standard: A statistical Illustration

    OpenAIRE

    Yukinobu Kitamura; Hiroshi Fujiki

    2004-01-01

    We demonstrate a statistical procedure for selecting the most suitable empirical model to test an economic theory, using the example of the test for purchasing power parity based on the Big Mac Index. Our results show that supporting evidence for purchasing power parity, conditional on the Balassa-Samuelson effect, depends crucially on the selection of models, sample periods and economies used for estimations.

  5. MacIntyre, Managerialism and Universities

    Science.gov (United States)

    Stolz, Steven A.

    2017-01-01

    MacIntyre's earlier work and concern with social science enquiry not only exposes its limits, but also provides an insight into how its knowledge claims have been put to ideological use. He maintains that the institutional embodiment of these ideological ideas is the bureaucratic manager who has had a negative role to play in social structures…

  6. Florence Jessie Mac Williams (1917-1990)

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 1. Florence Jessie Mac Williams (1917-1990). Featured Scientist Volume 10 Issue 1 January 2005 pp 98-98. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/010/01/0098-0098. Resonance ...

  7. An Interview with Peter MacDonald.

    Science.gov (United States)

    American Indian Journal, 1979

    1979-01-01

    Peter MacDonald, Chairman of the Navajo Nation, the largest tribe in the United States speaks to such issues as energy development/management, oil companies, Navajo-Hopi relocation legislation, traditionalism, and the role of the Council of Energy Resource Tribes. (RTS)

  8. Lifetime tests for MAC vertex chamber

    International Nuclear Information System (INIS)

    Nelson, H.N.

    1986-07-01

    A vertex chamber for MAC was proposed to increase precision in the measurement of the B hadron and tau lepton lifetimes. Thin-walled aluminized mylar drift tubes were used for detector elements. A study of radiation hardness was conducted under the conditions of the proposed design using different gases and different operating conditions

  9. A class of almost equilibrium states in Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Kueskue, Muharrem

    2008-01-01

    In quantum field theory in curved spacetimes the construction of the algebra of observables of linear fields is today well understood. However, it remains a non-trivial task to construct physically meaningful states on the algebra. For instance, we are in the unsatisfactory situation that there exist no examples of states suited to describe local thermal equilibrium in a non-stationary spacetime. In this thesis, we construct a class of states for the Klein-Gordon field in Robertson-Walker spacetimes, which seem to provide the first example of thermal states in a spacetime without time translation symmetry. More precisely, in the setting of real, linear, scalar fields in Robertson-Walker spacetimes we define on the set of homogeneous, isotropic, quasi-free states a free energy functional that is based on the averaged energy density measured by an isotropic observer along his worldline. This functional is well defined and lower bounded by a suitable quantum energy inequality. Subsequently, we minimize this functional and obtain states that we interpret as 'almost equilibrium states'. It turns out that the states of low energy are the ground states of the almost equilibrium states. Finally, we prove that the almost equilibrium states satisfy the Hadamard condition, which qualifies them as physically meaningful states. (orig.)

  10. Lake Robertson hydroelectric project. Construction of a roller compacted concrete dam

    Energy Technology Data Exchange (ETDEWEB)

    Labelle, M.; Robitaille, F. [Hydro-Quebec, Montreal, PQ (Canada)

    1995-12-31

    Construction of the Lake Robertson hydroelectric project on Quebec`s Lower North Shore was discussed in detail. The dam and powerhouse, located on the HaHa River, consists of a 134 m long concrete gravity dam, and a 21 MW powerhouse with two 69 kV transmission lines and four substations. The climate, terrain, and geography of the region, all of them characterized as severe, and the logistics of construction of the dam and power lines, aggravated by the isolation and severe conditions at the site, were described. The roller compacted concrete design and construction were noted, and justification for a concrete dam over an earth-fill dam was provided. Economics, properties, and composition of the roller compacted concrete (RCC) were examined, and control test results for the RCC concrete were provided. The use of RCC for the Lake Robertson development was described as successful in terms of the quality, watertightness, and completion time. The experience gained by the participants will make it possible to offer RCC as an alternative on various other projects. 2 figs.

  11. A class of almost equilibrium states in Robertson-Walker spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Kueskue, Muharrem

    2008-11-06

    In quantum field theory in curved spacetimes the construction of the algebra of observables of linear fields is today well understood. However, it remains a non-trivial task to construct physically meaningful states on the algebra. For instance, we are in the unsatisfactory situation that there exist no examples of states suited to describe local thermal equilibrium in a non-stationary spacetime. In this thesis, we construct a class of states for the Klein-Gordon field in Robertson-Walker spacetimes, which seem to provide the first example of thermal states in a spacetime without time translation symmetry. More precisely, in the setting of real, linear, scalar fields in Robertson-Walker spacetimes we define on the set of homogeneous, isotropic, quasi-free states a free energy functional that is based on the averaged energy density measured by an isotropic observer along his worldline. This functional is well defined and lower bounded by a suitable quantum energy inequality. Subsequently, we minimize this functional and obtain states that we interpret as 'almost equilibrium states'. It turns out that the states of low energy are the ground states of the almost equilibrium states. Finally, we prove that the almost equilibrium states satisfy the Hadamard condition, which qualifies them as physically meaningful states. (orig.)

  12. MACS as a tool for international inspections

    International Nuclear Information System (INIS)

    Curtiss, J.A.; Indusi, J.P.

    1995-01-01

    General acceptance of the challenge provision in the Chemical Weapons Convention has the potential for influence in other arms control areas. While most applications of the challenge inspection may be straightforward, there may be instances where access to the site by inspectors may be problematic. The MACS system described in this paper was developed to respond to these situations. Inspection and verification may be difficult when a host is unwilling,for valid reasons, to permit physical access to a site. We proposed a system of remote sensors which may be used to demonstrate compliance with Chemical Weapons Convention (CWC) challenge inspections even ff the inspector is physically excluded from a sensitive site. The system is based upon alternative-means-of-access provisions of the CWC. The Defense Nuclear Agency (DNA) funded design and construction of a system prototype, designated as MACS for Managed Access by Controlled Sensing. Features of the MACS design allow growth of the prototype into a versatile device for international monitoring of production facilities and other sites. MACS consists of instrumentation and communication equipment allowing site personnel to conduct a facility tour and perform acceptable measurements, while physically excluding the inspector from the facility. MACS consists of a base station used by the inspector, and a mobile unit used within the facility and manipulated by the facility staff. The base station and the mobile unit are at sign ed by a communication system, currently realized as a fiber optic cable. The mobile unit is equipped with television cameras and remote-reading distance-measuring equipment (DME) for use in verifying locations and dimensions. Global Positioning System receivers on the mobile unit provide both precise location and dead reckoning, suitable for tracking the mobile unit's position while within a building when satellite signals are not available

  13. Mammalian Synthetic Biology: Time for Big MACs.

    Science.gov (United States)

    Martella, Andrea; Pollard, Steven M; Dai, Junbiao; Cai, Yizhi

    2016-10-21

    The enabling technologies of synthetic biology are opening up new opportunities for engineering and enhancement of mammalian cells. This will stimulate diverse applications in many life science sectors such as regenerative medicine, development of biosensing cell lines, therapeutic protein production, and generation of new synthetic genetic regulatory circuits. Harnessing the full potential of these new engineering-based approaches requires the design and assembly of large DNA constructs-potentially up to chromosome scale-and the effective delivery of these large DNA payloads to the host cell. Random integration of large transgenes, encoding therapeutic proteins or genetic circuits into host chromosomes, has several drawbacks such as risks of insertional mutagenesis, lack of control over transgene copy-number and position-specific effects; these can compromise the intended functioning of genetic circuits. The development of a system orthogonal to the endogenous genome is therefore beneficial. Mammalian artificial chromosomes (MACs) are functional, add-on chromosomal elements, which behave as normal chromosomes-being replicating and portioned to daughter cells at each cell division. They are deployed as useful gene expression vectors as they remain independent from the host genome. MACs are maintained as a single-copy and can accommodate multiple gene expression cassettes of, in theory, unlimited DNA size (MACs up to 10 megabases have been constructed). MACs therefore enabled control over ectopic gene expression and represent an excellent platform to rapidly prototype and characterize novel synthetic gene circuits without recourse to engineering the host genome. This review describes the obstacles synthetic biologists face when working with mammalian systems and how the development of improved MACs can overcome these-particularly given the spectacular advances in DNA synthesis and assembly that are fuelling this research area.

  14. On the analytical solutions of the system of conformable time-fractional Robertson equations with 1-D diffusion

    International Nuclear Information System (INIS)

    Iyiola, O.S.; Tasbozan, O.; Kurt, A.; Çenesiz, Y.

    2017-01-01

    In this paper, we consider the system of conformable time-fractional Robertson equations with one-dimensional diffusion having widely varying diffusion coefficients. Due to the mismatched nature of the initial and boundary conditions associated with Robertson equation, there are spurious oscillations appearing in many computational algorithms. Our goal is to obtain an approximate solutions of this system of equations using the q-homotopy analysis method (q-HAM) and examine the widely varying diffusion coefficients and the fractional order of the derivative.

  15. The Dirac equation and the normalization of its solutions in a closed Friedmann- Robertson-Walker universe

    Science.gov (United States)

    Finster, Felix; Reintjes, Moritz

    2009-05-01

    We set up the Dirac equation in a Friedmann-Robertson-Walker geometry and separate the spatial and time variables. In the case of a closed universe, the spatial dependence is solved explicitly, giving rise to a discrete set of solutions. We compute the probability integral and analyze a spacetime normalization integral. This analysis allows us to introduce the fermionic projector in a closed Friedmann-Robertson-Walker geometry and to specify its global normalization as well as its local form. First author supported in part by the Deutsche Forschungsgemeinschaft.

  16. The periplasmic membrane proximal domain of MacA acts as a switch in stimulation of ATP hydrolysis by MacB transporter.

    Science.gov (United States)

    Modali, Sita D; Zgurskaya, Helen I

    2011-08-01

    Escherichia coli MacAB-TolC is a tripartite macrolide efflux transporter driven by hydrolysis of ATP. In this complex, MacA is the periplasmic membrane fusion protein that stimulates the activity of MacB transporter and establishes the link with the outer membrane channel TolC. The molecular mechanism by which MacA stimulates MacB remains unknown. Here, we report that the periplasmic membrane proximal domain of MacA plays a critical role in functional MacA-MacB interactions and stimulation of MacB ATPase activity. Binding of MacA to MacB stabilizes the ATP-bound conformation of MacB, whereas interactions with both MacB and TolC affect the conformation of MacA. A single G353A substitution in the C-terminus of MacA inactivates MacAB-TolC function by changing the conformation of the membrane proximal domain of MacA and disrupting the proper assembly of the MacA-MacB complex. We propose that MacA acts in transport by promoting MacB transition into the closed ATP-bound conformation and in this respect, is similar to the periplasmic solute-binding proteins. © 2011 Blackwell Publishing Ltd.

  17. MacBook All-in-One For Dummies

    CERN Document Server

    Chambers, Mark L

    2011-01-01

    Get comfortable and confident with your MacBook! Combining the fun-but-straightforward content of nine minibooks, this new edition of MacBook All-in-One For Dummies delivers helpful coverage of the rich features and essential tools you need to know to use the MacBook to its fullest potential. You'll learn an array of MacBook basics while veteran author Mark Chambers walks you through setting up your MacBook, running programs, finding files with Finder, searching with Spotlight, keeping track with Address Book, enjoying music with iTunes, creating cool multimedia projects with iLife, and more.

  18. MacBook Pro portable genius

    CERN Document Server

    Gruman, Galen

    2013-01-01

    Learn the skills, tools and shortcuts you need in order to make the most of your MacBook Pro This easy-to-use, compact guide skips the fluff and gets right to the essentials so that you can maximize all the latest features of the MacBook Pro. Packed with savvy insights and tips on key tools and shortcuts, this handy book aims to help you increase your productivity and save you time and hassle. From desktop sharing and wireless networking to running Windows applications and more, this book shows you what you want to know. Includes the latest version of OS X, iCloud, FaceTime, and moreCovers al

  19. Modeling MAC layer for powerline communications networks

    Science.gov (United States)

    Hrasnica, Halid; Haidine, Abdelfatteh

    2001-02-01

    The usage of electrical power distribution networks for voice and data transmission, called Powerline Communications, becomes nowadays more and more attractive, particularly in the telecommunication access area. The most important reasons for that are the deregulation of the telecommunication market and a fact that the access networks are still property of former monopolistic companies. In this work, first we analyze a PLC network and system structure as well as a disturbance scenario in powerline networks. After that, we define a logical structure of the powerline MAC layer and propose the reservation MAC protocols for the usage in the PLC network which provides collision free data transmission. This makes possible better network utilization and realization of QoS guarantees which can make PLC networks competitive to other access technologies.

  20. Millisecond timing on PCs and Macs.

    Science.gov (United States)

    MacInnes, W J; Taylor, T L

    2001-05-01

    A real-time, object-oriented solution for displaying stimuli on Windows 95/98, MacOS and Linux platforms is presented. The program, written in C++, utilizes a special-purpose window class (GLWindow), OpenGL, and 32-bit graphics acceleration; it avoids display timing uncertainty by substituting the new window class for the default window code for each system. We report the outcome of tests for real-time capability across PC and Mac platforms running a variety of operating systems. The test program, which can be used as a shell for programming real-time experiments and testing specific processors, is available at http://www.cs.dal.ca/~macinnwj. We propose to provide researchers with a sense of the usefulness of our program, highlight the ability of many multitasking environments to achieve real time, as well as caution users about systems that may not achieve real time, even under optimal conditions.

  1. Improved b lifetime measurement from MAC

    International Nuclear Information System (INIS)

    Ford, W.T.

    1984-03-01

    Two recent publications, from the MAC and Mark II collaborations, have reported the somewhat surprising result that the lifetime of particles made up of b quarks is in the 1 to 2 picosecond range, or somewhat longer than the lifetimes of charm particles. Although the charm decays are favored transitions while those of b particles depend upon off-diagonal elements of the weak flavor mixing matrix, the smallness of the b decay rates in face of the large available phase space indicates that the off-diagonal elements are indeed very small. The possibility for complete determination of the mixing matrix was brought significantly nearer by the availability of the lifetime information; what is needed now is to reduce the uncertainty of the measurements, which was about 33% for both experiments. We describe here an extension of the b lifetime study with the MAC detector, incorporating some new data and improvements in the analysis. 12 references

  2. Installing Git under MacOS

    OpenAIRE

    Fitzpatrick, Benjamin

    2015-01-01

    Step by step guide to installing the version control software Git under the Macintosh Operating System MacOS X (and later). Includes a seqeunce of screenshots with hand drawn arrows ;-) These slides are part of the materials for an Introductory course on the R language and environment for statistial computing. Free and Open Source materials for this course hosted on GitHub: https://github.com/brfitzpatrick/Intro_to_R

  3. Visualization of integrin Mac-1 in vivo.

    Science.gov (United States)

    Lim, Kihong; Hyun, Young-Min; Lambert-Emo, Kris; Topham, David J; Kim, Minsoo

    2015-11-01

    β2 integrins play critical roles in migration of immune cells and in the interaction with other cells, pathogens, and the extracellular matrix. Among the β2 integrins, Mac-1 (Macrophage antigen-1), composed of CD11b and CD18, is mainly expressed in innate immune cells and plays a major role in cell migration and trafficking. In order to image Mac-1-expressing cells both in live cells and mouse, we generated a knock-in (KI) mouse strain expressing CD11b conjugated with monomeric yellow fluorescent protein (mYFP). Expression of CD11b-mYFP protein was confirmed by Western blot and silver staining of CD11b-immunoprecipitates and total cell lysates from the mouse splenocytes. Mac-1-mediated functions of the KI neutrophils were comparable with those in WT cells. The fluorescence intensity of CD11b-mYFP was sufficient to image CD11b expressing cells in live mice using intravital two-photon microscopy. In vitro, dynamic changes in the intracellular localization of CD11b molecules could be measured by epifluorescent microscopy. Finally, CD11b-expressing immune cells from tissue were easily detected by flow cytometry without anti-CD11b antibody staining. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Finding revelation in anthropology: Alexander Winchell, William Robertson Smith and the heretical imperative.

    Science.gov (United States)

    Livingstone, David N

    2015-09-01

    Anthropological inquiry has often been considered an agent of intellectual secularization. Not least is this so in the sphere of religion, where anthropological accounts have often been taken to represent the triumph of naturalism. This metanarrative, however, fails to recognize that naturalistic explanations could sometimes be espoused for religious purposes and in defence of confessional creeds. This essay examines two late nineteenth-century figures--Alexander Winchell in the United States and William Robertson Smith in Britain--who found in anthropological analysis resources to bolster rather than undermine faith. In both cases these individuals found themselves on the receiving end of ecclesiastical censure and were dismissed from their positions at church-governed institutions. But their motivation was to vindicate divine revelation, in Winchell's case from the physical anthropology of human origins and in Smith's from the cultural anthropology of Semitic ritual.

  5. On the integrability of Friedmann-Robertson-Walker models with conformally coupled massive scalar fields

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, L A A [Programa de Pos-Graduacao em Fisica, Universidade do Estado do Rio de Janeiro, Rua Sao Francisco Xavier 524, Maracana, Rio de Janeiro, RJ, 20550-900 (Brazil); Skea, J E F [Departamento de Fisica Teorica, Instituto de Fisica, Universidade do Estado do Rio de Janeiro, Rua Sao Francisco Xavier 524, Maracana, Rio de Janeiro, RJ, 20550-900 (Brazil); Stuchi, T J [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68528, Rio de Janeiro, RJ, 21945-970 (Brazil)], E-mail: luis@dft.if.uerj.br, E-mail: jimsk@dft.if.uerj.br, E-mail: tstuchi@if.ufrj.br

    2008-02-22

    In this paper, we use a nonintegrability theorem by Morales and Ramis to analyse the integrability of Friedmann-Robertson-Walker cosmological models with a conformally coupled massive scalar field. We answer the long-standing question of whether these models with a vanishing cosmological constant and non-self-interacting scalar field are integrable: by applying Kovacic's algorithm to the normal variational equations, we prove analytically and rigorously that these equations and, consequently, the Hamiltonians are nonintegrable. We then address the models with a self-interacting massive scalar field and cosmological constant and show that, with the exception of a set of measure zero, the models are nonintegrable. For the spatially curved cases, we prove that there are no additional integrable cases other than those identified in the previous work based on the non-rigorous Painleve analysis. In our study of the spatially flat model, we explicitly obtain a new possibly integrable case.

  6. Stability of geodesic imcompleteness for Robertson-Walker space-times

    International Nuclear Information System (INIS)

    Beem, J.K.

    1981-01-01

    Let (M,g) be a Lorentzian warped product space-time M = (a, b) X H,g = -dt 2 x fh, where -infinity -infinity and (H,h) is homogeneous, then the past incompleteness of every timelike geodesic of (M,g) is stable under small C 0 perturbations in the space Lor(M) of Lorentzian metrics for M. Also it is shown that if (H,h) is isotropic and (M,g) contains a past-inextendible, past-incomplete null geodesic, then the past incompleteness of all null geodesics is stable under small C 1 perturbations in Lor(M). Given either the isotropy or homogeneity of the Riemannian factor, the background space-time (M,g) is globally hyperbolic. The results of this paper, in particular, answer a question raised by D. Lerner for big bang Robertson-Walker cosmological models affirmatively. (author)

  7. Effects of field interactions upon particle creation in Robertson-Walker universes

    International Nuclear Information System (INIS)

    Birrell, N.D.; Davies, P.C.W.; Ford, L.H.

    1980-01-01

    Particle creation due to field interactions in an expanding Robertson-Walker universe is investigated. A model in which pseudoscalar mesons and photons are created as a result of their mutual interaction is considered, and the energy density of created particles is calculated in model universes which undergo a bounce at some maximum curvature. The free-field creation of non-conformally coupled scalar particles and of gravitons is calculated in the same space-times. It is found that if the bounce occurs at a sufficiently early time the interacting particle creation will dominate. This result may be traced to the fact that the model interaction chosen introduces a length scale which is much larger than the Planck length. (author)

  8. Comments on the Dirac field in Friedmann-Robertson-Walker spacetime

    International Nuclear Information System (INIS)

    Khanal, U.

    2006-12-01

    Some further consequences about the massive Dirac field in Friedmann-Robertson-Walker universe are drawn. The comoving momenta of the particles in a closed universe are found to be quantized in units of half-integer, half being the contribution of the spin. This suggests that a gravitationally trapped fermion will have its momentum quantized. Both the comoving particle number and energy density are found not to be conserved in any finite volume of the universe. There exists a finite current that tends to enhance the density contrast. A series solution for the temporal part is used to show this effect. The particles distribute themselves in such a way as to resemble that required for the flattened rotation curves of galaxies. Although the total energy current grows with r, it is found that the current density, through unit area, goes down after attaining a peak. (author)

  9. Vaidya--Patel solution with Robertson--Walker metric as a rotating inflationary scenario

    International Nuclear Information System (INIS)

    Groen, O.; Soleng, H.H.

    1988-01-01

    The Vaidya--Patel solution of a rotating homogeneous fluid in the presence of a Maxwellian source-free electromagnetic field is interpretated as an inflationary scenario with a gauge field with local U(1) symmetry, a vacuum energy, and a rotating perfect fluid. An explicit solution is found to be expressible in terms of known solutions representing the radiation filled Robertson--Walker universe with a cosmological term. In the case that the rotating fluid is radiation, the discussion of the model is considerably simplified. How the time scale of transition into a pseudo-de Sitter stage, as observed by an observer following the rotating fluid, is affected by vorticity is also studied

  10. Power Saving MAC Protocols for WSNs and Optimization of S-MAC Protocol

    Directory of Open Access Journals (Sweden)

    Simarpreet Kaur

    2012-11-01

    Full Text Available Low power MAC protocols have received a lot of consideration in the last few years because of their influence on the lifetime of wireless sensor networks. Since, sensors typically operate on batteries, replacement of which is often difficult. A lot of work has been done to minimize the energy expenditure and prolong the sensor lifetime through energy efficient designs, across layers. Meanwhile, the sensor network should be able to maintain a certain throughput in order to fulfill the QoS requirements of the end user, and to ensure the constancy of the network. This paper introduces different types of MAC protocols used for WSNs and proposes S‐MAC, a Medium‐Access Control protocol designed for Wireless Sensor Networks. S‐MAC uses a few innovative techniques to reduce energy consumption and support selfconfiguration. A new protocol is suggested to improve the energy efficiency, latency and throughput of existing MAC protocol for WSNs. A modification of the protocol is then proposed to eliminate the need for some nodes to stay awake longer than the other nodes which improves the energy efficiency, latency and throughput and hence increases the life span of a wireless sensor network.

  11. Development of high yielding Soybean variety MACS 450 by using Kalitur mutant-MACS 111

    International Nuclear Information System (INIS)

    Raut, V.M.; Taware, S.P.; Halvankar, G.B.; Varghese, Philips

    2000-01-01

    A mutant variety -MACS 111 developed by treating seeds of indigenous black seeded 'Kalitur' variety with gamma irradiation + Ethyleneimine was used in development of high yielding varieties. MACS 450 a promising high yielding variety was selected from Bragg x MACS 111 cross by pedigree selection method. This variety gave the highest average seed yield in station trials (3422 kg/ha), coordinated breeding trials (2361 kg/ha) and varieties cum plant population trial (2215 kg/ha). On the basis of its performance in these trials it was released for commercial cultivation in Southern India. On all India basis, it also recorded the highest seed yield of 4076 kg/ha and 3582 kg/ha in Front line Demonstrations conducted on the farmers' field during 1998 and 1999 respectively. (author)

  12. One of the First Portable Macs

    CERN Multimedia

    1989-01-01

    It was one of the first portable macs released. The Portable had many new advances in mobile computing : The display was crispy clear, and looked beautiful when used in daylight ; The Portable came with a Lead-acid gel/cell battery that could run a anywhere from 6 -12 hours ; It supported to internal hard drives, and an external one. The reaction to the laptop was weak because it was slow, it had no capacity for expansion, it weighed heavily, its price was expensive. It has been stayed 1 year and half on the market.

  13. The periplasmic membrane proximal domain of MacA acts as a switch in stimulation of ATP hydrolysis by MacB transporter

    OpenAIRE

    Modali, Sita D.; Zgurskaya, Helen I.

    2011-01-01

    Escherichia coli MacAB-TolC is a tri-partite macrolide efflux transporter driven by hydrolysis of ATP. In this complex, MacA is the periplasmic membrane fusion protein that stimulates the activity of MacB transporter and establishes the link with the outer membrane channel TolC. The molecular mechanism by which MacA stimulates MacB remains unknown. Here, we report that the periplasmic membrane proximal domain of MacA plays a critical role in functional MacA-MacB interactions and stimulation o...

  14. Turning the Big Mac Index into the Medical MAC Index | Wilson ...

    African Journals Online (AJOL)

    Objective: The purpose of this study was to create a global medical earnings index, called the Medical MAC Index, to enable a comparison of what medical specialists earn in the countries included in the study. Design: The study gathered data on the earnings of specialist anaesthetists employed in state hospitals with five ...

  15. QL-MAC : a Q-learning based MAC for wireless sensor networks

    NARCIS (Netherlands)

    Galzarano, S.; Liotta, A.; Fortino, G.; Aversa, R.; Kolodziej, J.; Zhang, J.; Amato, F.; Fortino, G.

    2013-01-01

    WSNs are becoming an increasingly attractive technology thanks to the significant benefits they can offer to a wide range of application domains. Extending the system lifetime while preserving good network performance is one of the main challenges in WSNs. In this paper, a novel MAC protocol

  16. Essential Mac OS X panther server administration integrating Mac OS X server into heterogeneous networks

    CERN Document Server

    Bartosh, Michael

    2004-01-01

    If you've ever wondered how to safely manipulate Mac OS X Panther Server's many underlying configuration files or needed to explain AFP permission mapping--this book's for you. From the command line to Apple's graphical tools, the book provides insight into this powerful server software. Topics covered include installation, deployment, server management, web application services, data gathering, and more

  17. Mac OS X Snow Leopard Server For Dummies

    CERN Document Server

    Rizzo, John

    2009-01-01

    Making Everything Easier!. Mac OS® X Snow Leopard Server for Dummies. Learn to::;. Set up and configure a Mac network with Snow Leopard Server;. Administer, secure, and troubleshoot the network;. Incorporate a Mac subnet into a Windows Active Directory® domain;. Take advantage of Unix® power and security. John Rizzo. Want to set up and administer a network even if you don't have an IT department? Read on!. Like everything Mac, Snow Leopard Server was designed to be easy to set up and use. Still, there are so many options and features that this book will save you heaps of time and effort. It wa

  18. A Mobile Automated Characterization System (MACS) for indoor floor characterization

    International Nuclear Information System (INIS)

    Richardson, B.S.; Haley, D.C.; Dudar, A.M.; Ward, C.R.

    1995-01-01

    The Savannah River Technology Center (SRTC) and Oak Ridge National Laboratory are developing an advanced Mobile Automated Characterization System (MACS) to characterize indoor contaminated floors. MACS is based upon Semi-Intelligent Mobile Observing Navigator (SIMON), an earlier floor characterization system developed at SRTC. MACS will feature enhanced navigation systems, operator interface, and an interface to simplify integration of additional sensors. The enhanced navigation system will provide the capability to survey large open areas much more accurately than is now possible with SIMON, which is better suited for hallways and corridors that provide the means for recalibrating position and heading. MACS operator interface is designed to facilitate MACS's use as a tool for health physicists, thus eliminating the need for additional training in the robot's control language. Initial implementation of MACS will use radiation detectors. Additional sensors, such as PCB sensors currently being developed, will be integrated on MACS in the future. Initial use of MACS will be focused toward obtaining comparative results with manual methods. Surveys will be conducted both manually and with MACS to compare relative costs and data quality. While clear cost benefits anticipated, data quality benefits should be even more significant

  19. Corrected entropy of Friedmann-Robertson-Walker universe in tunneling method

    International Nuclear Information System (INIS)

    Zhu, Tao; Ren, Ji-Rong; Li, Ming-Fan

    2009-01-01

    In this paper, we study the thermodynamic quantities of Friedmann-Robertson-Walker (FRW) universe by using the tunneling formalism beyond semiclassical approximation developed by Banerjee and Majhi [25]. For this we first calculate the corrected Hawking-like temperature on apparent horizon by considering both scalar particle and fermion tunneling. With this corrected Hawking-like temperature, the explicit expressions of the corrected entropy of apparent horizon for various gravity theories including Einstein gravity, Gauss-Bonnet gravity, Lovelock gravity, f(R) gravity and scalar-tensor gravity, are computed. Our results show that the corrected entropy formula for different gravity theories can be written into a general expression (4.39) of a same form. It is also shown that this expression is also valid for black holes. This might imply that the expression for the corrected entropy derived from tunneling method is independent of gravity theory, spacetime and dimension of the spacetime. Moreover, it is concluded that the basic thermodynamical property that the corrected entropy on apparent horizon is a state function is satisfied by the FRW universe

  20. Dispersion, Topological Scattering, and Self-Interference in Multiply Connected Robertson-Walker Cosmologies

    CERN Document Server

    Tomaschitz, R

    1994-01-01

    We investigate scattering effects in open Robertson-Walker cosmologies whose spacelike slices are multiply connected hyperbolic manifolds. We work out an example in which the 3-space is infinite and has the topology of a solid torus. The world-lines in these cosmologies are unstable, and classical probability densities evolving under the horospherical geodesic flow show dispersion, as do the densities of scalar wave packets. The rate of dispersion depends crucially on the expansion factor, and we calculate the time evolution of their widths. We find that the cosmic expansion can confine dispersion: The diameter of the domain of chaoticity in the 3-manifold provides the natural, time-dependent length unit in an infinite, multiply connected universe. In a toroidal 3-space manifold this diameter is just the length of the limit cycle. On this scale we find that the densities take a finite limit width in the late stage of the expansion. In the early stage classical densities and conformally coupled fields approach...

  1. A measure on the set of compact Friedmann-Lemaitre-Robertson-Walker models

    International Nuclear Information System (INIS)

    Roukema, Boudewijn F; Blanloeil, Vincent

    2010-01-01

    Compact, flat Friedmann-Lemaitre-Robertson-Walker (FLRW) models have recently regained interest as a good fit to the observed cosmic microwave background temperature fluctuations. However, it is generally thought that a globally, exactly flat FLRW model is theoretically improbable. Here, in order to obtain a probability space on the set F of compact, comoving, 3-spatial sections of FLRW models, a physically motivated hypothesis is proposed, using the density parameter Ω as a derived rather than fundamental parameter. We assume that the processes that select the 3-manifold also select a global mass-energy and a Hubble parameter. The requirement that the local and global values of Ω are equal implies a range in Ω that consists of a single real value for any 3-manifold. Thus, the obvious measure over F is the discrete measure. Hence, if the global mass-energy and Hubble parameter are a function of 3-manifold choice among compact FLRW models, then probability spaces parametrized by Ω do not, in general, give a zero probability of a flat model. Alternatively, parametrization by a spatial size parameter, the injectivity radius r inj , suggests the Lebesgue measure. In this case, the probability space over the injectivity radius implies that flat models occur almost surely (a.s.), in the sense of probability theory, and non-flat models a.s. do not occur.

  2. A measure on the set of compact Friedmann-Lemaitre-Robertson-Walker models

    Energy Technology Data Exchange (ETDEWEB)

    Roukema, Boudewijn F [Torun Centre for Astronomy, Nicolaus Copernicus University, ul. Gagarina 11, 87-100 Torun (Poland); Blanloeil, Vincent [IRMA, Departement de Mathematiques, Universite de Strasbourg, 7 rue Rene Descartes, 67084 Strasbourg, Cedex (France)

    2010-12-21

    Compact, flat Friedmann-Lemaitre-Robertson-Walker (FLRW) models have recently regained interest as a good fit to the observed cosmic microwave background temperature fluctuations. However, it is generally thought that a globally, exactly flat FLRW model is theoretically improbable. Here, in order to obtain a probability space on the set F of compact, comoving, 3-spatial sections of FLRW models, a physically motivated hypothesis is proposed, using the density parameter {Omega} as a derived rather than fundamental parameter. We assume that the processes that select the 3-manifold also select a global mass-energy and a Hubble parameter. The requirement that the local and global values of {Omega} are equal implies a range in {Omega} that consists of a single real value for any 3-manifold. Thus, the obvious measure over F is the discrete measure. Hence, if the global mass-energy and Hubble parameter are a function of 3-manifold choice among compact FLRW models, then probability spaces parametrized by {Omega} do not, in general, give a zero probability of a flat model. Alternatively, parametrization by a spatial size parameter, the injectivity radius r{sub inj}, suggests the Lebesgue measure. In this case, the probability space over the injectivity radius implies that flat models occur almost surely (a.s.), in the sense of probability theory, and non-flat models a.s. do not occur.

  3. A determination of the absolute radiant energy of a Robertson-Berger meter sunburn unit

    Science.gov (United States)

    DeLuisi, John J.; Harris, Joyce M.

    Data from a Robertson-Berger (RB) sunburn meter were compared with concurrent measurements obtained with an ultraviolet double monochromator (DM), and the absolute energy of one sunburn unit measured by the RB-meter was determined. It was found that at a solar zenith angle of 30° one sunburn unit (SU) is equivalent to 35 ± 4 mJ cm -2, and at a solar zenith angle of 69°, one SU is equivalent to 20 ± 2 mJ cm -2 (relative to a wavelength of 297 nm), where the rate of change is non-linear. The deviation is due to the different response functions of the RB-meter and the DM system used to simulate the response of human skin to the incident u.v. solar spectrum. The average growth rate of the deviation with increasing solar zenith angle was found to be 1.2% per degree between solar zenith angles 30 and 50° and 2.3% per degree between solar zenith angles 50 and 70°. The deviations of response with solar zenith angle were found to be consistent with reported RB-meter characteristics.

  4. Evolution in fluctuating environments: decomposing selection into additive components of the Robertson-Price equation.

    Science.gov (United States)

    Engen, Steinar; Saether, Bernt-Erik

    2014-03-01

    We analyze the stochastic components of the Robertson-Price equation for the evolution of quantitative characters that enables decomposition of the selection differential into components due to demographic and environmental stochasticity. We show how these two types of stochasticity affect the evolution of multivariate quantitative characters by defining demographic and environmental variances as components of individual fitness. The exact covariance formula for selection is decomposed into three components, the deterministic mean value, as well as stochastic demographic and environmental components. We show that demographic and environmental stochasticity generate random genetic drift and fluctuating selection, respectively. This provides a common theoretical framework for linking ecological and evolutionary processes. Demographic stochasticity can cause random variation in selection differentials independent of fluctuating selection caused by environmental variation. We use this model of selection to illustrate that the effect on the expected selection differential of random variation in individual fitness is dependent on population size, and that the strength of fluctuating selection is affected by how environmental variation affects the covariance in Malthusian fitness between individuals with different phenotypes. Thus, our approach enables us to partition out the effects of fluctuating selection from the effects of selection due to random variation in individual fitness caused by demographic stochasticity. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  5. Approximate KMS states for scalar and spinor fields in Friedmann-Robertson-Walker spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Dappiaggi, Claudio; Hack, Thomas-Paul [Hamburg Univ. (Germany). II. Inst. fuer Theoretische Physik; Pinamonti, Nicola [Roma ' ' Tor Vergata' ' Univ. (Italy). Dipt. di Matematica

    2010-09-15

    We construct and discuss Hadamard states for both scalar and Dirac spinor fields in a large class of spatially flat Friedmann-Robertson-Walker spacetimes characterised by an initial phase either of exponential or of power-law expansion. The states we obtain can be interpreted as being in thermal equilibrium at the time when the scale factor a has a specific value a = a{sub 0}. In the case a{sub 0} = 0, these states fulfil a strict KMS condition on the boundary of the spacetime, which is either a cosmological horizon, or a Big Bang hypersurface. Furthermore, in the conformally invariant case, they are conformal KMS states on the full spacetime. However, they provide a natural notion of an approximate KMS state also in the remaining cases, especially for massive fields. On the technical side, our results are based on a bulk-to-boundary reconstruction technique already successfully applied in the scalar case and here proven to be suitable also for spinor fields. The potential applications of the states we find range over a broad spectrum, but they appear to be suited to discuss in particular thermal phenomena such as the cosmic neutrino background or the quantum state of dark matter. (orig.)

  6. Approximate KMS states for scalar and spinor fields in Friedmann-Robertson-Walker spacetimes

    International Nuclear Information System (INIS)

    Dappiaggi, Claudio; Hack, Thomas-Paul; Pinamonti, Nicola

    2010-09-01

    We construct and discuss Hadamard states for both scalar and Dirac spinor fields in a large class of spatially flat Friedmann-Robertson-Walker spacetimes characterised by an initial phase either of exponential or of power-law expansion. The states we obtain can be interpreted as being in thermal equilibrium at the time when the scale factor a has a specific value a = a 0 . In the case a 0 = 0, these states fulfil a strict KMS condition on the boundary of the spacetime, which is either a cosmological horizon, or a Big Bang hypersurface. Furthermore, in the conformally invariant case, they are conformal KMS states on the full spacetime. However, they provide a natural notion of an approximate KMS state also in the remaining cases, especially for massive fields. On the technical side, our results are based on a bulk-to-boundary reconstruction technique already successfully applied in the scalar case and here proven to be suitable also for spinor fields. The potential applications of the states we find range over a broad spectrum, but they appear to be suited to discuss in particular thermal phenomena such as the cosmic neutrino background or the quantum state of dark matter. (orig.)

  7. Effect of electromagnetic fields on the creation of scalar particles in a flat Robertson-Walker space-time

    International Nuclear Information System (INIS)

    Haouat, S.; Chekireb, R.

    2012-01-01

    The influence of electromagnetic fields on the creation of scalar particles from vacuum in a flat Robertson-Walker space-time is studied. The Klein-Gordon equation with varying electric field and constant magnetic one is solved. The Bogoliubov transformation method is applied to calculate the pair creation probability and the number density of created particles. It is shown that the electric field amplifies the creation of scalar particles while the magnetic field minimizes it. (orig.)

  8. Global bifurcation of solutions of the mean curvature spacelike equation in certain Friedmann-Lemaître-Robertson-Walker spacetimes

    Science.gov (United States)

    Dai, Guowei; Romero, Alfonso; Torres, Pedro J.

    2018-06-01

    We study the existence of spacelike graphs for the prescribed mean curvature equation in the Friedmann-Lemaître-Robertson-Walker (FLRW) spacetime. By using a conformal change of variable, this problem is translated into an equivalent problem in the Lorentz-Minkowski spacetime. Then, by using Rabinowitz's global bifurcation method, we obtain the existence and multiplicity of positive solutions for this equation with 0-Dirichlet boundary condition on a ball. Moreover, the global structure of the positive solution set is studied.

  9. Steven MacCall: Winner of LJ's 2010 Teaching Award

    Science.gov (United States)

    Berry, John N., III

    2010-01-01

    This article profiles Steven L. MacCall, winner of "Library Journal's" 2010 Teaching Award. An associate professor at the School of Library and Information Studies (SLIS) at the University of Alabama, Tuscaloosa, MacCall was nominated by Kathie Popadin, known as "Kpop" to the members of her cohort in the online MLIS program at SLIS. Sixteen of…

  10. Paradox applications integration ATP's for MAC and mass balance programs

    International Nuclear Information System (INIS)

    Russell, V.K.; Mullaney, J.E.

    1994-01-01

    The K Basins Materials Accounting (MAC) and Material Balance (MBA) database system were set up to run under one common applications program. This Acceptance Test Plan (ATP) describes how the code was to be tested to verify its correctness. The scope of the tests is minimal, since both MAC and MBA have already been tested in detail as stand-alone programs

  11. Lifetime tests for MAC vertex chamber

    International Nuclear Information System (INIS)

    Nelson, H.

    1986-01-01

    A vertex chamber for MAC was proposed in fall 1983 to increase precision in the measurement of the B hadron and tau lepton lifetimes. The chamber had to be placed within the existing central drift chamber, making access for repairs difficult and costly. Therefore for detector elements thin-walled aluminized mylar drift tubes (straws) were used because of their simplicity and robustness. The diameter of the drift tubes was 6.9 mm. The radial extent of the proposed chamber was from 3 cm to 10 cm, the inner wall of the central drift. It was clear that radiation levels, from synchrotron x-rays and overfocussed electrons, were potentially high. Since the drift distance is short in the straws, it was desirable to operate them at the highest possible gas gain, to achieve the best spatial resolution. There was a likelihood of drawing large currents in the chamber and thus causing radiation damage. Therefore a study of radiation hardness under the conditions of their proposed design was undertaken. In tests, argon-hydrocarbon mixtures consistently became unusable at ∼0.05 C/cm collected charge, due to anode buildup. Argon-CO 2 mixtures, while underquenched, were operational to 0.25 C/cm, at which point loss of cathode material became intolerable. Argon-xenon-CO 2 proved to be quenched as well as argon-hydrocarbons, but was limited by cathode damage. The MAC vertex chamber has operated at a distance of 4.6 cm from the e + e - interaction point at PEP for two years and has shown no aging effects

  12. Vacuum fluctuations and topological Casimir effect in Friedmann-Robertson-Walker cosmologies with compact dimensions

    International Nuclear Information System (INIS)

    Saharian, A.A.; Mkhitaryan, A.L.

    2010-01-01

    We investigate the Wightman function, the vacuum expectation values of the field squared and the energy-momentum tensor for a massless scalar field with general curvature coupling parameter in spatially flat Friedmann-Robertson-Walker universes with an arbitrary number of toroidally compactified dimensions. The topological parts in the expectation values are explicitly extracted and in this way the renormalization is reduced to that for the model with trivial topology. In the limit when the comoving lengths of the compact dimensions are very short compared to the Hubble length, the topological parts coincide with those for a conformal coupling and they are related to the corresponding quantities in the flat spacetime by standard conformal transformation. This limit corresponds to the adiabatic approximation. In the opposite limit of large comoving lengths of the compact dimensions, in dependence of the curvature coupling parameter, two regimes are realized with monotonic or oscillatory behavior of the vacuum expectation values. In the monotonic regime and for non-conformally and non-minimally coupled fields the vacuum stresses are isotropic and the equation of state for the topological parts in the energy density and pressures is of barotropic type. For conformal and minimal couplings the leading terms in the corresponding asymptotic expansions vanish and the vacuum stresses, in general, are anisotropic, though the equation of state remains of barotropic type. In the oscillatory regime, the amplitude of the oscillations for the topological part in the expectation value of the field squared can be either decreasing or increasing with time, whereas for the energy-momentum tensor the oscillations are damping. The limits of validity of the adiabatic approximation are discussed. (orig.)

  13. TreeMAC: Localized TDMA MAC protocol for real-time high-data-rate sensor networks

    Science.gov (United States)

    Song, W.-Z.; Huang, R.; Shirazi, B.; Husent, R.L.

    2009-01-01

    Earlier sensor network MAC protocols focus on energy conservation in low-duty cycle applications, while some recent applications involve real-time high-data-rate signals. This motivates us to design an innovative localized TDMA MAC protocol to achieve high throughput and low congestion in data collection sensor networks, besides energy conservation. TreeMAC divides a time cycle into frames and frame into slots. Parent determines children's frame assigmnent based on their relative bandwidth demand, and each node calculates its own slot assignment based on its hop-count to the sink. This innovative 2-dimensional frame-slot assignment algorithm has the following nice theory properties. Firstly, given any node, at any time slot, there is at most one active sender in its neighborhood (includ ing itself). Secondly, the packet scheduling with TreelMAC is bufferless, which therefore minimizes the probability of network congestion. Thirdly, the data throughput to gateway is at least 1/3 of the optimum assuming reliable links. Our experiments on a 24 node test bed demonstrate that TreeMAC protocol significantly improves network throughput and energy efficiency, by comparing to the TinyOS's default CSMA MAC protocol and a recent TDMA MAC protocol Funneling-MAC[8]. ?? 2009 IEEE.

  14. GENETIC FINGERPRINTING OF MYCOBACTERIUM AVIUM COMPLEX (MAC) ORGANISMS ISOLATED FROM HOSPITAL PATIENTS AND THE ENVIRONMENT

    Science.gov (United States)

    A particularly pathogenic group of mycobacteria belong to the Mycobacterium avium complex (MAC), which includes M. avium and M. intracellulare. MAC organisms cause disease in children, the elderly, and immuno-compromised individuals. A critical step in preventing MAC infections...

  15. Increased NMDA receptor inhibition at an increased Sevoflurane MAC

    Directory of Open Access Journals (Sweden)

    Brosnan Robert J

    2012-06-01

    Full Text Available Abstract Background Sevoflurane potently enhances glycine receptor currents and more modestly decreases NMDA receptor currents, each of which may contribute to immobility. This modest NMDA receptor antagonism by sevoflurane at a minimum alveolar concentration (MAC could be reciprocally related to large potentiation of other inhibitory ion channels. If so, then reduced glycine receptor potency should increase NMDA receptor antagonism by sevoflurane at MAC. Methods Indwelling lumbar subarachnoid catheters were surgically placed in 14 anesthetized rats. Rats were anesthetized with sevoflurane the next day, and a pre-infusion sevoflurane MAC was measured in duplicate using a tail clamp method. Artificial CSF (aCSF containing either 0 or 4 mg/mL strychnine was then infused intrathecally at 4 μL/min, and the post-infusion baseline sevoflurane MAC was measured. Finally, aCSF containing strychnine (either 0 or 4 mg/mL plus 0.4 mg/mL dizocilpine (MK-801 was administered intrathecally at 4 μL/min, and the post-dizocilpine sevoflurane MAC was measured. Results Pre-infusion sevoflurane MAC was 2.26%. Intrathecal aCSF alone did not affect MAC, but intrathecal strychnine significantly increased sevoflurane requirement. Addition of dizocilpine significantly decreased MAC in all rats, but this decrease was two times larger in rats without intrathecal strychnine compared to rats with intrathecal strychnine, a statistically significant (P  Conclusions Glycine receptor antagonism increases NMDA receptor antagonism by sevoflurane at MAC. The magnitude of anesthetic effects on a given ion channel may therefore depend on the magnitude of its effects on other receptors that modulate neuronal excitability.

  16. MacRuby Ruby and Cocoa on OS X

    CERN Document Server

    Aimonetti, Matt

    2011-01-01

    Want to build native Mac OS X applications with a sleek, developer-friendly alternative to Objective-C? MacRuby is an ideal choice. This in-depth guide shows you how Apple's implementation of Ruby gives you access to all the features available to Objective-C programmers. You'll get clear, detailed explanations of MacRuby, including quick programming techniques such as prototyping. Perfect for programmers at any level, this book is packed with code samples and complete project examples. If you use Ruby, you can tap your skills to take advantage of Interface Builder, Cocoa libraries, the Objec

  17. iMac G3 Blueberry 350MHz

    CERN Multimedia

    2000-01-01

    The iMac G3 is an all-in-one personal computer, encompassing both the monitor and the computer in one package. It allowed to revitalize the Apple brand that was in decline and close to financial ruin. Originally released in striking bondi blue and later a range of other translucent plastic envelopes in bright colors. The iMac comes with a keyboard and mouse matching the color of the case. The iMac G3 was sold from 1998 to 2003 and has been updated many times.

  18. Multichannel MAC Layer In Mobile Ad—Hoc Network

    Science.gov (United States)

    Logesh, K.; Rao, Samba Siva

    2010-11-01

    This paper we presented the design objectives and technical challenges in Multichannel MAC protocols in Mobile Ad-hoc Network. In IEEE 802.11 a/b/g standards allow use of multiple channels, only a single channel is popularly used, due to the lack of efficient protocols that enable use of Multiple Channels. Even though complex environments in ad hoc networks require a combined control of physical (PHY) and medium access control (MAC) layers resources in order to optimize performance. And also we discuss the characteristics of cross-layer frame and give a multichannel MAC approach.

  19. The MacNuclide nuclear data environment

    International Nuclear Information System (INIS)

    Stone, C.A.

    1992-01-01

    Advance in technology have produced intriguing tools that can be applied to problems in nuclear science. Information management in nuclear science is an example of how technology is not quickly exploited. The U.S. Department of Energy supports an extensive program to evaluate published nuclear properties and store them in an electronic data base. Much of the evaluation effort has focused on producing the journal Nuclear Data Sheets and the publication Table of Isotopes. Although the electronic data base can itself be a valuable source of information, the software used to access is was designed using decades-old technologies. The authors of this paper have developed a novel data-base management system for nuclear properties. The application is known as MacNuclide. It is a nuclear data-base environment that uses the highly interactive and intuitive windowing environmentsof desk-top computers. The environment is designed around that image of the chart of nuclides. Questions are posed to the data base by placing constraints on properties and defining collections of nuclides to be used in data-base seraches. Results are displayed either as a simple list of nuclides that meet the imposed constraints or as a color chart of nuclides

  20. Infecting Windows, Linux & Mac in one go

    CERN Multimedia

    Computer Security Team

    2012-01-01

    Still love bashing on Windows as you believe it is an insecure operating system? Hold on a second! Just recently, a vulnerability has been published for Java 7.   It affects Windows/Linux PCs and Macs, Internet Explorer, Safari and Firefox. In fact, it affects all computers that have enabled the Java 7 plug-in in their browser (Java 6 and earlier is not affected). Once you visit a malicious website (and there are plenty already out in the wild), your computer is infected… That's "Game Over" for you.      And this is not the first time. For a while now, attackers have not been targeting the operating system itself, but rather aiming at vulnerabilities inherent in e.g. your Acrobat Reader, Adobe Flash or Java programmes. All these are standard plug-ins added into your favourite web browser which make your web-surfing comfortable (or impossible when you un-install them). A single compromised web-site, however, is sufficient to prob...

  1. Competition at the Wireless Sensor Network MAC Layer: Low Power Probing interfering with X-MAC

    International Nuclear Information System (INIS)

    Zacharias, Sven; Newe, Thomas

    2011-01-01

    Wireless Sensor Networks (WSNs) combine sensors with computer networks and enable very dense, in-situ and live measurements of data over a large area. Since this emerging technology has the potential to be embedded almost everywhere for numberless applications, interference between different networks can become a serious issue. For most WSNs, it is assumed today that the network medium access is non-competitive. On the basis of X-MAC interfered by Low Power Probing, this paper shows the danger and the effects of different sensor networks communicating on a single wireless channel of the 2.4 GHz band, which is used by the IEEE 802.15.4 standard.

  2. Competition at the Wireless Sensor Network MAC Layer: Low Power Probing interfering with X-MAC

    Energy Technology Data Exchange (ETDEWEB)

    Zacharias, Sven; Newe, Thomas, E-mail: Sven.Zacharias@ul.ie [University of Limerick (Ireland)

    2011-08-17

    Wireless Sensor Networks (WSNs) combine sensors with computer networks and enable very dense, in-situ and live measurements of data over a large area. Since this emerging technology has the potential to be embedded almost everywhere for numberless applications, interference between different networks can become a serious issue. For most WSNs, it is assumed today that the network medium access is non-competitive. On the basis of X-MAC interfered by Low Power Probing, this paper shows the danger and the effects of different sensor networks communicating on a single wireless channel of the 2.4 GHz band, which is used by the IEEE 802.15.4 standard.

  3. Competition at the Wireless Sensor Network MAC Layer: Low Power Probing interfering with X-MAC

    Science.gov (United States)

    Zacharias, Sven; Newe, Thomas

    2011-08-01

    Wireless Sensor Networks (WSNs) combine sensors with computer networks and enable very dense, in-situ and live measurements of data over a large area. Since this emerging technology has the potential to be embedded almost everywhere for numberless applications, interference between different networks can become a serious issue. For most WSNs, it is assumed today that the network medium access is non-competitive. On the basis of X-MAC interfered by Low Power Probing, this paper shows the danger and the effects of different sensor networks communicating on a single wireless channel of the 2.4 GHz band, which is used by the IEEE 802.15.4 standard.

  4. On defects of the volume and curvature of the Robertson-Walker metric and construction of cosmological models

    International Nuclear Information System (INIS)

    Gackstatter, F.

    1987-01-01

    For the Robertson-Walker metric (RWM) normal coordinates are constructed and the Riemann curvature tensor is determined. Then results on the defects of the volume and curvature, derived formerly, are applied to the RWM and to cosmological models. Finally cosmological models are constructed, they describe different states of the development of the cosmos: p ∼ 0, 1/3u, 2/3u, in a unified form. A Laurent expansion of the density of energy u and pressure p is used to solve the Friedmann equations. (author)

  5. Comment on 'Quantization of Friedmann-Robertson-Walker spacetimes in the presence of a negative cosmological constant and radiation'

    International Nuclear Information System (INIS)

    Amore, Paolo; Aranda, Alfredo; Cervantes, Mayra; Diaz-Cruz, J. L.; Fernandez, Francisco M.

    2007-01-01

    The quantization of the Friedmann-Robertson-Walker spacetime in the presence of a negative cosmological constant was used in a recent paper to conclude that there are solutions that avoid singularities (big bang-big crunch) at the quantum level. We show that a proper study of their model does not indicate that it prevents the occurrence of singularities at the quantum level, in fact the quantum probability of such event is larger than the classical one. Our numerical simulations based on the powerful variational sinc collocation method (VSCM) also show that the precision of the results of that paper is much lower than the 20 significant digits reported by the authors

  6. MAC mini acceptance test procedure, software Version 3.0

    International Nuclear Information System (INIS)

    Russell, V.K.

    1994-01-01

    The K Basins Materials Accounting (MAC) programs had some major improvements made to it to organize the main-tables by Location, Canister, and Material. This ATP describes how the code was to be tested to verify its correctness

  7. Mechatronical Aided Concept (MAC) in Intelligent Transport Vehicles Design

    OpenAIRE

    Pavel Pavlasek

    2003-01-01

    This article deals with the principles of synergy effect of mechatronical aided concept (MAC) to the design of intelligent transport vehicles products applying CA technologies and virtual reality design methods. Also includes presentation of intelligent railway vehicle development.

  8. Mac OS X : Tiger edition the missing manual

    CERN Document Server

    Pogue, David

    2005-01-01

    You can set your watch to it: As soon as Apple comes out with another version of Mac OS X, David Pogue hits the streets with another meticulous Missing Manual to cover it with a wealth of detail. The new Mac OS X 10.4, better known as Tiger, is faster than its predecessors, but nothing's too fast for Pogue and Mac OS X: The Missing Manual. There are many reasons why this is the most popular computer book of all time. With its hallmark objectivity, the Tiger Edition thoroughly explores the latest features to grace the Mac OS. Which ones work well and which do not? What should you look for? Th

  9. MAC layer security issues in wireless mesh networks

    Science.gov (United States)

    Reddy, K. Ganesh; Thilagam, P. Santhi

    2016-03-01

    Wireless Mesh Networks (WMNs) have emerged as a promising technology for a broad range of applications due to their self-organizing, self-configuring and self-healing capability, in addition to their low cost and easy maintenance. Securing WMNs is more challenging and complex issue due to their inherent characteristics such as shared wireless medium, multi-hop and inter-network communication, highly dynamic network topology and decentralized architecture. These vulnerable features expose the WMNs to several types of attacks in MAC layer. The existing MAC layer standards and implementations are inadequate to secure these features and fail to provide comprehensive security solutions to protect both backbone and client mesh. Hence, there is a need for developing efficient, scalable and integrated security solutions for WMNs. In this paper, we classify the MAC layer attacks and analyze the existing countermeasures. Based on attacks classification and countermeasures analysis, we derive the research directions to enhance the MAC layer security for WMNs.

  10. Nora Tully MacAlvay--Her Life in the Theatre.

    Science.gov (United States)

    Webb, Dorothy

    1996-01-01

    Recounts the life and times of a pioneer children's theater playwright and fiction author, Nora Tully MacAlvay (1900-86). Points out that her interest in children's theater and children's literature was lifelong and intense. (PA)

  11. MacMillan Pier Transportation Center Feasibility Study.

    Science.gov (United States)

    2006-06-01

    The MacMillan Pier Transportation Center Feasibility Study examines two potential sites (landside and waterside) for a transportation center that provides a range of tourist and traveler information. It would serve as a gateway for Provincetown and t...

  12. After MacIntyre : Kaasaegsest vooruseetikast / Meego Remmel

    Index Scriptorium Estoniae

    Remmel, Meego

    2006-01-01

    Alasdair MacIntyre panus 20. sajandi eetikasse. Tema käsitlus vooruseetikast ja vooruseetilisest perspektiivist, mida on võimalik näha komplekselt, vaadeldes voorust, praktikat, narratiivi ja traditsiooni mõisteid

  13. Big Mac arvestab raha ostujõudu / Harli Uljas

    Index Scriptorium Estoniae

    Uljas, Harli

    2005-01-01

    The Economist võrdleb maailma valuutade suhestamiseks Big Mac'i burgeri hindu 120 riigis, kuna see meetod võimaldab saada ülevaate riikide elanikkonna tegelikust ostujõust. Tabel: Hamburgeri standard

  14. Aeronautical Mobile Airport Communications System (AeroMACS)

    Science.gov (United States)

    Budinger, James M.; Hall, Edward

    2011-01-01

    To help increase the capacity and efficiency of the nation s airports, a secure wideband wireless communications system is proposed for use on the airport surface. This paper provides an overview of the research and development process for the Aeronautical Mobile Airport Communications System (AeroMACS). AeroMACS is based on a specific commercial profile of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard known as Wireless Worldwide Interoperability for Microwave Access or WiMAX (WiMax Forum). The paper includes background on the need for global interoperability in air/ground data communications, describes potential AeroMACS applications, addresses allocated frequency spectrum constraints, summarizes the international standardization process, and provides findings and recommendations from the world s first AeroMACS prototype implemented in Cleveland, Ohio, USA.

  15. A Mac Protocol Implementation for Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Jamila Bhar

    2015-01-01

    Full Text Available IEEE 802.15.4 is an important standard for Low Rate Wireless Personal Area Network (LRWPAN. The IEEE 802.15.4 presents a flexible MAC protocol that provides good efficiency for data transmission by adapting its parameters according to characteristics of different applications. In this research work, some restrictions of this standard are explained and an improvement of traffic efficiency by optimizing MAC layer is proposed. Implementation details for several blocks of communication system are carefully modeled. The protocol implementation is done using VHDL language. The analysis gives a full understanding of the behavior of the MAC protocol with regard to backoff delay, data loss probability, congestion probability, slot effectiveness, and traffic distribution for terminals. Two ideas are proposed and tested to improve efficiency of CSMA/CA mechanism for IEEE 802.15.4 MAC Layer. Primarily, we dynamically adjust the backoff exponent (BE according to queue level of each node. Secondly, we vary the number of consecutive clear channel assessment (CCA for packet transmission. We demonstrate also that slot compensation provided by the enhanced MAC protocol can greatly avoid unused slots. The results show the significant improvements expected by our approach among the IEEE 802.15.4 MAC standards. Synthesis results show also hardware performances of our proposed architecture.

  16. CHARGED DUST GRAIN DYNAMICS SUBJECT TO SOLAR WIND, POYNTING–ROBERTSON DRAG, AND THE INTERPLANETARY MAGNETIC FIELD

    Energy Technology Data Exchange (ETDEWEB)

    Lhotka, Christoph; Bourdin, Philippe; Narita, Yasuhito, E-mail: christoph.lhotka@oeaw.ac.at, E-mail: philippe.bourdin@oeaw.ac.at, E-mail: yasuhito.narita@oeaw.ac.at [Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, A-8042 Graz (Austria)

    2016-09-01

    We investigate the combined effect of solar wind, Poynting–Robertson drag, and the frozen-in interplanetary magnetic field on the motion of charged dust grains in our solar system. For this reason, we derive a secular theory of motion by the means of an averaging method and validate it with numerical simulations of the unaveraged equations of motions. The theory predicts that the secular motion of charged particles is mainly affected by the z -component of the solar magnetic axis, or the normal component of the interplanetary magnetic field. The normal component of the interplanetary magnetic field leads to an increase or decrease of semimajor axis depending on its functional form and sign of charge of the dust grain. It is generally accepted that the combined effects of solar wind and photon absorption and re-emmision (Poynting–Robertson drag) lead to a decrease in semimajor axis on secular timescales. On the contrary, we demonstrate that the interplanetary magnetic field may counteract these drag forces under certain circumstances. We derive a simple relation between the parameters of the magnetic field, the physical properties of the dust grain, as well as the shape and orientation of the orbital ellipse of the particle, which is a necessary conditions for the stabilization in semimajor axis.

  17. Connectivity-Based Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs

    Directory of Open Access Journals (Sweden)

    Woo-Yong Choi

    2009-01-01

    Full Text Available We propose the efficient reliable multicast MAC protocol based on the connectivity information among the recipients. Enhancing the BMMM (Batch Mode Multicast MAC protocol, the reliable multicast MAC protocol significantly reduces the RAK (Request for ACK frame transmissions in a reasonable computational time and enhances the MAC performance. By the analytical performance analysis, the throughputs of the BMMM protocol and our proposed MAC protocol are derived. Numerical examples show that our proposed MAC protocol increases the reliable multicast MAC performance for IEEE 802.11 wireless LANs.

  18. Human radiation studies: Remembering the early years: Oral history of physician James S. Robertson, M.D., Ph.D., conducted January 20, 1995

    International Nuclear Information System (INIS)

    1995-09-01

    This report is a transcript of in interview of Dr. James S. Robertson by representatives of the DOE Office of Human Radiation Experiments. Dr. Robertson was chosen for this interview because of his research at Brookhaven National Laboratory, especially on Boron Neutron Capture Therapy (BNCT); his work at the United States Naval Defense Laboratory; and his work at the Atomic Energy Commission. After a brief biographical sketch Dr. Robertson discusses research on human subjects at Berkeley, his contributions to the beginnings of Neutron Capture Therapy at Brookhaven, his participation with the Brookhaven Human Use Committee, his involvement in the study of the effects of Castle Bravo event on the Marshallese, and his work with the Naval Radiological Defense Laboratory

  19. The University of Toronto's lasting contribution to war surgery: how Maj. L. Bruce Robertson fundamentally transformed thinking toward blood transfusion during the First World War.

    Science.gov (United States)

    Tien, Abigail; Beckett, Andrew; Pannell, Dylan

    2017-06-01

    During the Great War, Canadian military surgeons produced some of the greatest innovations to improve survival on the battlefield. Arguably, the most important was bringing blood transfusion practice close to the edge of the battlefield to resuscitate the many casualties dying of hemorrhagic shock. Dr. L. Bruce Robertson of the Canadian Army Medical Corps was the pioneering surgeon from the University of Toronto who was able to demonstrate the benefit of blood transfusions near the front line and counter the belief that saline was the resuscitation fluid of choice in military medicine. Robertson would go on to survive the Great War, but would be taken early in life by influenza. Despite his life and career being cut short, Robertson's work is still carried on today by many military medical organizations who strive to bring blood to the wounded in austere and dangerous settings. This article has an Appendix, available at canjsurg.ca.

  20. Human radiation studies: Remembering the early years: Oral history of physician James S. Robertson, M.D., Ph.D., conducted January 20, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This report is a transcript of in interview of Dr. James S. Robertson by representatives of the DOE Office of Human Radiation Experiments. Dr. Robertson was chosen for this interview because of his research at Brookhaven National Laboratory, especially on Boron Neutron Capture Therapy (BNCT); his work at the United States Naval Defense Laboratory; and his work at the Atomic Energy Commission. After a brief biographical sketch Dr. Robertson discusses research on human subjects at Berkeley, his contributions to the beginnings of Neutron Capture Therapy at Brookhaven, his participation with the Brookhaven Human Use Committee, his involvement in the study of the effects of Castle Bravo event on the Marshallese, and his work with the Naval Radiological Defense Laboratory.

  1. Learning Unix for Mac OS X Tiger Unlock the Power of Unix

    CERN Document Server

    Taylor, Dave

    2005-01-01

    Thoroughly revised and updated for Mac OS X Tiger, this new edition introduces Mac users to the Terminal application and shows you how to navigate the command interface, explore hundreds of Unix applications that come with the Mac, and, most importantly, how to take advantage of both the Mac and Unix interfaces. If you want to master the command-line, this gentle guide to using Unix on Mac OS X Tiger is well worth its cover price

  2. Victor Bérard et la Macédoine

    Directory of Open Access Journals (Sweden)

    Ivan Savev

    2011-01-01

    Full Text Available Un helléniste convaincu, Victor Bérard, en vient, au début du XXe siècle à soutenir l’existence de « Macédoniens » et le slogan « la Macédoine aux Macédoniens”.Le Congrès de Berlin en 1878 avait laissé la Macédoine aux mains des Ottomans. La Grèce, la Serbie et la Bulgarie, parvenues à ses limites et prévoyant le retrait futur des Ottomans peaufinent les arguments linguistiques et historiques qui justifieront leurs revendications territoriales. Victor Bérard, un helléniste respecté et bon connaisseur de la région sud balkanique, effectue des enquêtes en Macédoine en 1896 et 1903 qu’il publie à Paris.Cette étude montre comment, dans le contexte de la propagande nationaliste des prétendants à la possession de la Macédoine, Victor Bérard en vient progressivement à affirmer qu’il existe une population autochtone, les Macédoniens. Il soutient leur programme pour la constitution d’une fédération ou confédération avec le slogan « la Macédoine aux Macédoniens » ce qui fait toute l’actualité de ses ouvrages.In 1878, the Congress of Berlin had left Macedonia in the hands of the Ottomans. Greece, Serbia and Bulgaria had reached its limits. Anticipating the Ottoman retreat, they polish language and historical arguments that will justify their territorial claims. Victor Bérard, a respected Hellenist and a good expert of the southern Balkans, is doing researches in Macedonia in 1896 and 1903. These will be later published in Paris.This study shows how, in the context of the nationalist propaganda build-up made by the candidates for the possession of Macedonia, Victor Bérard comes progressively to assert the existence of a native population: the Macedonians. He supports their program for the forming of a federation or confederation which slogan would be “Macedonia to Macedonians”. This makes his works very topical.

  3. Design and FPGA implementation for MAC layer of Ethernet PON

    Science.gov (United States)

    Zhu, Zengxi; Lin, Rujian; Chen, Jian; Ye, Jiajun; Chen, Xinqiao

    2004-04-01

    Ethernet passive optical network (EPON), which represents the convergence of low-cost, high-bandwidth and supporting multiple services, appears to be one of the best candidates for the next-generation access network. The work of standardizing EPON as a solution for access network is still underway in the IEEE802.3ah Ethernet in the first mile (EFM) task force. The final release is expected in 2004. Up to now, there has been no standard application specific integrated circuit (ASIC) chip available which fulfills the functions of media access control (MAC) layer of EPON. The MAC layer in EPON system has many functions, such as point-to-point emulation (P2PE), Ethernet MAC functionality, multi-point control protocol (MPCP), network operation, administration and maintenance (OAM) and link security. To implement those functions mentioned above, an embedded real-time operating system (RTOS) and a flexible programmable logic device (PLD) with an embedded processor are used. The software and hardware functions in MAC layer are realized through programming embedded microprocessor and field programmable gate array(FPGA). Finally, some experimental results are given in this paper. The method stated here can provide a valuable reference for developing EPON MAC layer ASIC.

  4. Dolphin natures, human virtues: MacIntyre and ethical naturalism.

    Science.gov (United States)

    Glackin, Shane Nicholas

    2008-09-01

    Can biological facts explain human morality? Aristotelian 'virtue' ethics has traditionally assumed so. In recent years Alasdair MacIntyre has reintroduced a form of Aristotle's 'metaphysical biology' into his ethics. He argues that the ethological study of dependence and rationality in other species--dolphins in particular--sheds light on how those same traits in the typical lives of humans give rise to the moral virtues. However, some goal-oriented dolphin behaviour appears both dependent and rational in the precise manner which impresses MacIntyre, yet anything but ethically 'virtuous'. More damningly, dolphin ethologists consistently refuse to evaluate such behaviour in the manner MacIntyre claims is appropriate to moral judgement. In light of this, I argue that virtues--insofar as they name a biological or ethological category--do not name a morally significant one.

  5. Office for iPad and Mac for dummies

    CERN Document Server

    Weverka, Peter

    2015-01-01

    The easy way to work with Office on your iPad or Mac Are you a Mac user who isn't accustomed to working with Microsoft Office? Consider this friendly guide your go-to reference! Written in plain English and packed with easy-to-follow, step-by-step instructions, Office for iPad and Mac For Dummies walks you through every facet of Office, from installing the software and opening files to working with Word, Excel, PowerPoint, and Outlook-and beyond. Plus, you'll discover how to manage files, share content and collaborate online through social media, and find help when you need it. Two things a

  6. Performance analysis and improvement of WPAN MAC for home networks.

    Science.gov (United States)

    Mehta, Saurabh; Kwak, Kyung Sup

    2010-01-01

    The wireless personal area network (WPAN) is an emerging wireless technology for future short range indoor and outdoor communication applications. The IEEE 802.15.3 medium access control (MAC) is proposed to coordinate the access to the wireless medium among the competing devices, especially for short range and high data rate applications in home networks. In this paper we use analytical modeling to study the performance analysis of WPAN (IEEE 802.15.3) MAC in terms of throughput, efficient bandwidth utilization, and delay with various ACK policies under error channel condition. This allows us to introduce a K-Dly-ACK-AGG policy, payload size adjustment mechanism, and Improved Backoff algorithm to improve the performance of the WPAN MAC. Performance evaluation results demonstrate the impact of our improvements on network capacity. Moreover, these results can be very useful to WPAN application designers and protocol architects to easily and correctly implement WPAN for home networking.

  7. Performance Analysis and Improvement of WPAN MAC for Home Networks

    Directory of Open Access Journals (Sweden)

    Saurabh Mehta

    2010-03-01

    Full Text Available The wireless personal area network (WPAN is an emerging wireless technology for future short range indoor and outdoor communication applications. The IEEE 802.15.3 medium access control (MAC is proposed to coordinate the access to the wireless medium among the competing devices, especially for short range and high data rate applications in home networks. In this paper we use analytical modeling to study the performance analysis of WPAN (IEEE 802.15.3 MAC in terms of throughput, efficient bandwidth utilization, and delay with various ACK policies under error channel condition. This allows us to introduce a K-Dly-ACK-AGG policy, payload size adjustment mechanism, and Improved Backoff algorithm to improve the performance of the WPAN MAC. Performance evaluation results demonstrate the impact of our improvements on network capacity. Moreover, these results can be very useful to WPAN application designers and protocol architects to easily and correctly implement WPAN for home networking.

  8. Activity Modelling and Comparative Evaluation of WSN MAC Security Attacks

    DEFF Research Database (Denmark)

    Pawar, Pranav M.; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2012-01-01

    and initiate security attacks that disturb the normal functioning of the network in a severe manner. Such attacks affect the performance of the network by increasing the energy consumption, by reducing throughput and by inducing long delays. Of all existing WSN attacks, MAC layer attacks are considered...... the most harmful as they directly affect the available resources and thus the nodes’ energy consumption. The first endeavour of this paper is to model the activities of MAC layer security attacks to understand the flow of activities taking place when mounting the attack and when actually executing it....... The second aim of the paper is to simulate these attacks on hybrid MAC mechanisms, which shows the performance degradation of aWSN under the considered attacks. The modelling and implementation of the security attacks give an actual view of the network which can be useful in further investigating secure...

  9. SACRB-MAC: A High-Capacity MAC Protocol for Cognitive Radio Sensor Networks in Smart Grid.

    Science.gov (United States)

    Yang, Zhutian; Shi, Zhenguo; Jin, Chunlin

    2016-03-31

    The Cognitive Radio Sensor Network (CRSN) is considered as a viable solution to enhance various aspects of the electric power grid and to realize a smart grid. However, several challenges for CRSNs are generated due to the harsh wireless environment in a smart grid. As a result, throughput and reliability become critical issues. On the other hand, the spectrum aggregation technique is expected to play an important role in CRSNs in a smart grid. By using spectrum aggregation, the throughput of CRSNs can be improved efficiently, so as to address the unique challenges of CRSNs in a smart grid. In this regard, we proposed Spectrum Aggregation Cognitive Receiver-Based MAC (SACRB-MAC), which employs the spectrum aggregation technique to improve the throughput performance of CRSNs in a smart grid. Moreover, SACRB-MAC is a receiver-based MAC protocol, which can provide a good reliability performance. Analytical and simulation results demonstrate that SACRB-MAC is a promising solution for CRSNs in a smart grid.

  10. Analog model of a Friedmann-Robertson-Walker universe in Bose-Einstein condensates: Application of the classical field method

    International Nuclear Information System (INIS)

    Jain, Piyush; Weinfurtner, Silke; Visser, Matt; Gardiner, C. W.

    2007-01-01

    Analog models of gravity have been motivated by the possibility of investigating phenomena not readily accessible in their cosmological counterparts. In this paper, we investigate the analog of cosmological particle creation in a Friedmann-Robertson-Walker universe by numerically simulating a Bose-Einstein condensate with a time-dependent scattering length. In particular, we focus on a two-dimensional homogeneous condensate using the classical field method via the truncated Wigner approximation. We show that for various forms of the scaling function the particle production is consistent with the underlying theory in the long wavelength limit. In this context, we further discuss the implications of modified dispersion relations that arise from the microscopic theory of a weakly interacting Bose gas

  11. Solution of radial spin-1 field equation in Robertson-Walker space-time via Heun's equation

    International Nuclear Information System (INIS)

    Zecca, A.

    2010-01-01

    The spin-1 field equation is considered in Robertson-Walker spacetime. The problem of the solution of the separated radial equations, previously discussed in the flat space-time case, is solved also for both the closed and open curvature case. The radial equation is reduced to Heun's differential equation that recently has been widely reconsidered. It is shown that the solution of the present Heun equation does not fall into the class of polynomial-like or hypergeometric functions. Heun's operator results also non-factorisable. The properties follow from application of general theorems and power series expansion. In the positive curvature case of the universe a discrete energy spectrum of the system is found. The result follows by requiring a polynomial-like behaviour of at least one component of the spinor field. Developments and applications of the theory suggest further study of the solution of Heun's equation.

  12. Generalized Robertson-Walker Space-Time Admitting Evolving Null Horizons Related to a Black Hole Event Horizon.

    Science.gov (United States)

    Duggal, K L

    2016-01-01

    A new technique is used to study a family of time-dependent null horizons, called " Evolving Null Horizons " (ENHs), of generalized Robertson-Walker (GRW) space-time [Formula: see text] such that the metric [Formula: see text] satisfies a kinematic condition. This work is different from our early papers on the same issue where we used (1 + n )-splitting space-time but only some special subcases of GRW space-time have this formalism. Also, in contrast to previous work, we have proved that each member of ENHs is totally umbilical in [Formula: see text]. Finally, we show that there exists an ENH which is always a null horizon evolving into a black hole event horizon and suggest some open problems.

  13. Vehicle Health Management Communications Requirements for AeroMACS

    Science.gov (United States)

    Kerczewski, Robert J.; Clements, Donna J.; Apaza, Rafael D.

    2012-01-01

    As the development of standards for the aeronautical mobile airport communications system (AeroMACS) progresses, the process of identifying and quantifying appropriate uses for the system is progressing. In addition to defining important elements of AeroMACS standards, indentifying the systems uses impacts AeroMACS bandwidth requirements. Although an initial 59 MHz spectrum allocation for AeroMACS was established in 2007, the allocation may be inadequate; studies have indicated that 100 MHz or more of spectrum may be required to support airport surface communications. Hence additional spectrum allocations have been proposed. Vehicle health management (VHM) systems, which can produce large volumes of vehicle health data, were not considered in the original bandwidth requirements analyses, and are therefore of interest in supporting proposals for additional AeroMACS spectrum. VHM systems are an emerging development in air vehicle safety, and preliminary estimates of the amount of data that will be produced and transmitted off an aircraft, both in flight and on the ground, have been prepared based on estimates of data produced by on-board vehicle health sensors and initial concepts of data processing approaches. This allowed an initial estimate of VHM data transmission requirements for the airport surface. More recently, vehicle-level systems designed to process and analyze VHM data and draw conclusions on the current state of vehicle health have been undergoing testing and evaluation. These systems make use of vehicle system data that is mostly different from VHM data considered previously for airport surface transmission, and produce processed system outputs that will be also need to be archived, thus generating additional data load for AeroMACS. This paper provides an analysis of airport surface data transmission requirements resulting from the vehicle level reasoning systems, within the context of overall VHM data requirements.

  14. Mapping of MAC Address with Moving WiFi Scanner

    Directory of Open Access Journals (Sweden)

    Arief Hidayat

    2017-10-01

    Full Text Available Recently, Wifi is one of the most useful technologies that can be used for detecting and counting MAC Address. This paper described using of WiFi scanner which carried out seven times circulated the bus. The method used WiFi and GPS are to counting MAC address as raw data from the pedestrian smartphone, bus passenger or WiFi devices near from the bus as long as the bus going around the route. There are seven processes to make map WiFi data.

  15. MacVEE - the intimate Macintosh-VME system

    International Nuclear Information System (INIS)

    Taylor, B.G.

    1986-01-01

    The marriage of a mass-produced personal computer with the versatile VMEbus and CAMAC systems creates a cost-effective solution to many laboratory small system requirements. This paper describes MacVEE (Microcomputer Applied to the Control of VME Electronic Equipment), a novel system in which an Apple Macintosh computer is equipped with a special interface which allows it direct memory-mapped access to single or multiple VME and CAMAC crates interconnected by a ribbon cable bus. The bus is driven by an electronics plinth called MacPlinth, which attaches to the computer and becomes an integral part of it. (Auth.)

  16. MacIntyre's Moral Theory and Moral Relativism

    OpenAIRE

    Ali Abedi Renani

    2017-01-01

    In this paper, I seek to explain the similarity and disparity between MacIntyre’s moral theory and moral relativism. I will argue that MacIntyre’s moral theory can escape the charge of moral relativism because both his earlier social and his later metaphysical approaches appeal to some criteria, the human telos or universal human qualities respectively. The notion of telos is wider than the notion of function which is defined in social contexts. If there is a context-transcending notion of te...

  17. Muusikamaailm : Ateena konkurss tuleb esinduslik. Kaks raamatut juubilar-lauljatest. David Robertson lahkub Pariisist. Jean-Pierre Rampal surnud / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2000-01-01

    Septembris Ateenas toimuvast D. Mitropoulose nim. rahvusvahelisest noorte dirigentide konkursist. Saksamaal ilmus kaks raamatut nimekatelt lauljatelt ئ D. Fischer-Dieskau "Zeit eines Lebens. Auf Fährtensuche" ja J. King'i "Nun sollt Ihr mich befragen". D. Robertson lahkub Ensemble InterContemporaini kunstilise juhi kohalt, dirigendi edasisest tegevuskavast. J.-P. Rampal'i muusikuteest

  18. ‘Dirty work’, but someone has to do it: Howard P. Robertson and the refereeing practices of Physical Review in the 1930s

    Science.gov (United States)

    Lalli, Roberto

    2016-01-01

    In the 1930s the mathematical physicist Howard P. Robertson was the main referee of the journal Physical Review for papers concerning general relativity and related subjects. The rich correspondence between Robertson and the editors of the journal enables a historical investigation of the refereeing process of Physical Review at the time that it was becoming one of the most influential physics periodicals in the world. By focusing on this case study, the paper investigates two complementary aspects of the evolution of the refereeing process: first, the historical evolution of the refereeing practices in connection with broader contextual changes, and second, the attempts to define the activity of the referee, including the epistemic virtues required and the journal's functions according to the participants' categories. By exploring the tension between Robertson's idealized picture about how the referee should behave and the desire to promote his intellectual agenda, I show that the evaluation criteria that Robertson employed were contextually dependent and I argue that, in the 1930s, through his reports the referee had an enormous power in defining what direction future research should take. PMID:27386715

  19. Directional Medium Access Control (MAC Protocols in Wireless Ad Hoc and Sensor Networks: A Survey

    Directory of Open Access Journals (Sweden)

    David Tung Chong Wong

    2015-06-01

    Full Text Available This survey paper presents the state-of-the-art directional medium access control (MAC protocols in wireless ad hoc and sensor networks (WAHSNs. The key benefits of directional antennas over omni-directional antennas are longer communication range, less multipath interference, more spatial reuse, more secure communications, higher throughput and reduced latency. However, directional antennas lead to single-/multi-channel directional hidden/exposed terminals, deafness and neighborhood, head-of-line blocking, and MAC-layer capture which need to be overcome. Addressing these problems and benefits for directional antennas to MAC protocols leads to many classes of directional MAC protocols in WAHSNs. These classes of directional MAC protocols presented in this survey paper include single-channel, multi-channel, cooperative and cognitive directional MACs. Single-channel directional MAC protocols can be classified as contention-based or non-contention-based or hybrid-based, while multi-channel directional MAC protocols commonly use a common control channel for control packets/tones and one or more data channels for directional data transmissions. Cooperative directional MAC protocols improve throughput in WAHSNs via directional multi-rate/single-relay/multiple-relay/two frequency channels/polarization, while cognitive directional MAC protocols leverage on conventional directional MAC protocols with new twists to address dynamic spectrum access. All of these directional MAC protocols are the pillars for the design of future directional MAC protocols in WAHSNs.

  20. Link-layer Jamming Attacks on S-MAC

    NARCIS (Netherlands)

    Law, Y.W.; Hartel, Pieter H.; den Hartog, Jeremy; Havinga, Paul J.M.

    2004-01-01

    We argue that among denial-of-service (DoS) attacks, link-layer jamming is a more attractive option to attackers than radio jamming is. By exploiting the semantics of the link-layer protocol (aka MAC protocol), an attacker can achieve better efficiency than blindly jamming the radio signals alone.

  1. Link-layer jamming attacks on S-MAC

    NARCIS (Netherlands)

    Law, Y.W.; Hartel, Pieter H.; den Hartog, Jeremy; Havinga, Paul J.M.

    We argue that among denial-of-service (DoS) attacks, link-layer jamming is a more attractive option to attackers than radio jamming is. By exploiting the semantics of the link-layer protocol (aka MAC protocol), an attacker can achieve better efficiency than blindly jamming the radio signals alone.

  2. Traffic Adaptive MAC Protocols in Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Farhan Masud

    2017-01-01

    Full Text Available In Wireless Body Area Networks (WBANs, every healthcare application that is based on physical sensors is responsible for monitoring the vital signs data of patient. WBANs applications consist of heterogeneous and dynamic traffic loads. Routine patient’s observation is described as low-load traffic while an alarming situation that is unpredictable by nature is referred to as high-load traffic. This paper offers a thematic review of traffic adaptive Medium Access Control (MAC protocols in WBANs. First, we have categorized them based on their goals, methods, and metrics of evaluation. The Zigbee standard IEEE 802.15.4 and the baseline MAC IEEE 802.15.6 are also reviewed in terms of traffic adaptive approaches. Furthermore, a comparative analysis of the protocols is made and their performances are analyzed in terms of delay, packet delivery ratio (PDR, and energy consumption. The literature shows that no review work has been done on traffic adaptive MAC protocols in WBANs. This review work, therefore, could add enhancement to traffic adaptive MAC protocols and will stimulate a better way of solving the traffic adaptivity problem.

  3. God, Sport Philosophy, Kinesiology: A MacIntyrean Examination

    Science.gov (United States)

    Twietmeyer, Gregg

    2015-01-01

    Sport philosophy is in crisis. This subdiscipline of kinesiology garners little to no respect and few tenure track lines in kinesiology departments. Why is this the case? Why isn't philosophy held in greater esteem? Is it possible that philosopher Alasdair MacIntyre's (2009) diagnosis found in "God, Philosophy, Universities" could…

  4. Florence Jessie MacWilliams (1917-1990)

    Indian Academy of Sciences (India)

    famous mathematician Oscar Zariski, well known for his work in algebraic geometry, at. Johns Hopkins University, following him to Harvard University to study with him for a year. There was a break in her studies for many years following her marriage in 1941 to. W al ter Mac Williams, an engineer, and the birth and raising of ...

  5. Evaluation of the MacDonald scabbler for highway use.

    Science.gov (United States)

    1975-01-01

    The MacDonald Scabbler is a small, hand held machine suitable for use in cleaning and roughening concrete surfaces, It weighs 308 pounds (140 kg), has 11 cutting heads, and, as a power source, requires a compressor capable of delivering 365 cubic foo...

  6. Integrated, Kerberized Login on MacOS X

    Science.gov (United States)

    Hotz, Henry B.

    2006-01-01

    Context for this information. MacOS X login process and available hooks. Authorization Services configuration. Authorization Services plug-in s. Kerberos plug-in s. Other bugs and recommendations. Authorization Services Called by loginwindow, screen saver and fast user switching. It calls Directory Services, Login Hook, and Login Items (System Preferences).

  7. Increasing the permeability of Escherichia coli using MAC13243

    DEFF Research Database (Denmark)

    Muheim, Claudio; Götzke, Hansjörg; Eriksson, Anna U.

    2017-01-01

    molecules that make the outer membrane of Escherichia coli more permeable. We identified MAC13243, an inhibitor of the periplasmic chaperone LolA that traffics lipoproteins from the inner to the outer membrane. We observed that cells were (1) more permeable to the fluorescent probe 1-N...

  8. Mechatronical Aided Concept (MAC in Intelligent Transport Vehicles Design

    Directory of Open Access Journals (Sweden)

    Pavel Pavlasek

    2003-01-01

    Full Text Available This article deals with the principles of synergy effect of mechatronical aided concept (MAC to the design of intelligent transport vehicles products applying CA technologies and virtual reality design methods. Also includes presentation of intelligent railway vehicle development.

  9. MAC mini acceptance test procedures, software Version 3.3

    International Nuclear Information System (INIS)

    Russell, V.K.

    1994-01-01

    The K Basins Materials Accounting (MAC) programs had some improvements made to it to to change slightly the access authorized users had to the modification of critical data. This ATP describes how the code was to be tested to verify its correctness

  10. TR-MAC: an energy-efficient MAC protocol for wireless sensor networks exploiting noise-based transmitted reference modulation

    NARCIS (Netherlands)

    Morshed, S.; Dimitrova, D.C.; Brogle, M.; Braun, T.; Heijenk, Gerhard J.

    Energy-constrained behavior of sensor nodes is one of the most important criteria for successful deployment of wireless sensor net- works. The medium access control (MAC) protocol determines the time a sensor node transceiver spends listening or transmitting, and hence the energy consumption of the

  11. Library Signage: Applications for the Apple Macintosh and MacPaint.

    Science.gov (United States)

    Diskin, Jill A.; FitzGerald, Patricia

    1984-01-01

    Describes specific applications of the Macintosh computer at Carnegie-Mellon University Libraries, where MacPaint was used as a flexible, easy to use, and powerful tool to produce informational, instructional, and promotional signage. Profiles of system hardware and software, an evaluation of the computer program MacPaint, and MacPaint signage…

  12. Design of an autonomous decentralized MAC protocol for wireless sensor networks

    NARCIS (Netherlands)

    van Hoesel, L.F.W.; Dal Pont, L.; Havinga, Paul J.M.

    In this document the design of a MAC protocol for wireless sensor networks is discussed. The autonomous decentralized TDMA based MAC protocol minimizes power consumtion by efficiency implementing unicast/omnicast, scheduled rendezvous times and wakeup calls. The MAC protocol is an ongoing research

  13. Teaching a Classic for All Ages: Fairy Tales and Stories of George MacDonald.

    Science.gov (United States)

    Sadler, Glenn Edward

    1995-01-01

    Discusses the life and writings of George MacDonald (1824-1905). Suggests that the most striking feature of MacDonald's children's books is his sensitivity toward spiritual values and the power of change within the lives of his characters. Appends a list of questions to stimulate student response to MacDonald's writings. (RS)

  14. McMAC: Towards a MAC Protocol with Multi-Constrained QoS Provisioning for Diverse Traffic in Wireless Body Area Networks

    OpenAIRE

    Monowar, Muhammad; Hassan, Mohammad; Bajaber, Fuad; Al-Hussein, Musaed; Alamri, Atif

    2012-01-01

    The emergence of heterogeneous applications with diverse requirements for resource-constrained Wireless Body Area Networks (WBANs) poses significant challenges for provisioning Quality of Service (QoS) with multi-constraints (delay and reliability) while preserving energy efficiency. To address such challenges, this paper proposes McMAC, a MAC protocol with multi-constrained QoS provisioning for diverse traffic classes in WBANs. McMAC classifies traffic based on their multi-constrained QoS de...

  15. Una lectura interpretativa de Tras la virtud, de Alasdair MacIntyre - An Interpretive Reading of After Virtue, by Alasdair MacIntyre

    Directory of Open Access Journals (Sweden)

    Fernando Fernández-Llebrez

    2010-12-01

    Full Text Available This article centers on the thought of Alasdair MacIntyre, whose most prominente work, After Virtue, is considered a classic of political science. In contrast with other reviews, this article will examine After Virtue within the broader context of MacIntyre’s thinking and publications. An overview of MacIntyre’s literary corpus and the evolution of his thinking will shed light on the volume examined and trace certain ideas that are characteristic of this Scottish political philosopher. Matters that remained unsettled in After Virtue have become over time more defined in MacIntyre’s thinking, such as the influence exerted upon him by Thomas Aquinas.

  16. Mac OS X Snow Leopard for Power Users Advanced Capabilities and Techniques

    CERN Document Server

    Granneman, Scott

    2010-01-01

    Mac OS X Snow Leopard for Power Users: Advanced Capabilities and Techniques is for Mac OS X users who want to go beyond the obvious, the standard, and the easy. If want to dig deeper into Mac OS X and maximize your skills and productivity using the world's slickest and most elegant operating system, then this is the book for you. Written by Scott Granneman, an experienced teacher, developer, and consultant, Mac OS X for Power Users helps you push Mac OS X to the max, unveiling advanced techniques and options that you may have not known even existed. Create custom workflows and apps with Automa

  17. Environmental monitoring of the Robertson Reservoir (1990-2005) : evolution of the mercury levels in the flesh of fish

    International Nuclear Information System (INIS)

    Therrien, J.

    2006-04-01

    This paper provided details of an environmental monitoring analysis of the stomach contents and mercury levels in the flesh of main fish species in the Robertson Reservoir. The report noted that smelt species were dominant in the reservoir and in the adjoining Ivry Lake, while benthos were dominant the brackish waters of Lake Monger. Sticklebacks were found in the stomachs of the examined fish, while the diet of brook trout was comprised mainly of benthos in lakes and reservoirs. Arctic char mainly ate benthos in the reservoir. Landlocked salmon mainly ate fish in the reservoirs and lakes. Smelt was the primary diet of Arctic char until 2003. After 2003, Arctic char fed mainly on sticklebacks. It was observed that average mercury levels of fish of a standardized length increased by a factor of 2.7 to 4.9 after the impoundment of the reservoir. However, average mercury levels stopped increasing for dwarf Arctic char in 2003. Levels of mercury in brook trout have not increased since 1999. A significant decrease in mercury levels of rainbow smelt were observed. Average mercury levels of fish in the brackish waters of Lake Monger were lower than levels observed in most other freshwater lakes in the region. It was concluded that the number of monthly meals recommended by the fish consumption guide produced in 2001 for the Gros Mecatina region are still appropriate for the reservoir

  18. Temperature differences within the detector of the Robertson-Berger sunburn meter, model 500, compared to global radiation

    Science.gov (United States)

    Kjeldstad, Berit; Grandum, Oddbjorn

    1993-11-01

    The Robertson-Berger sunburn meter, model 500, has no temperature compensation, and the effect of temperature on the instrument response has been investigated and discussed in several reports. It is recommended to control the temperature of the detector or at least measure it. The temperature sensor is recommended to be positioned within the detector unit. We have measured the temperature at three different positions in the detector: At the edge of the green filter where the phosphor layer is placed; at the glass tube covering the cathode; and, finally, the air temperature inside the instrument. These measurements have been performed outdoors since July 1991, with corresponding measurements of the global and direct solar radiation. There was no difference between the temperature of the glasstube covering the cathode and the air inside the instrument, at any radiation level. However, there was a difference between the green filter and the two others. The difference is linearly dependent on the amount of global radiation. The temperature difference, (Delta) T (temperature between the green filter and the air inside the sensor), increased 0.8 degree(s)C when the global irradiation increased by 100 W/m2. At maximum global radiation in Trondheim (latitude 63.4 degree(s)N) (Delta) T was approximately 5 - 6 K when the global radiation was about 700 W/m2. This was valid for temperatures between 7 degree(s)C and 30 degree(s)C. Only clear days were evaluated.

  19. Affordability of cataract surgery using the Big Mac prices

    OpenAIRE

    Van C. Lansingh; Marissa J. Carter; Kristen A. Eckert; Kevin L. Winthrop; João M. Furtado; Serge Resnikoff

    2015-01-01

    Purpose: One barrier to cataract surgery is its high price in some countries. This study aims to understand to what extent the price of cataract surgery is over- or undervalued and whether it varies in relation to GDP using The Economist newspaper Big Mac Index (BMcI) methodology, which measures the purchasing power parity between different currencies. Methods: Peer-reviewed articles containing information on cataract surgery prices were searched from 1993 to June 2012 in databases. Ophtha...

  20. ITER management advisory committee (MAC) meeting in Naka

    International Nuclear Information System (INIS)

    Yoshikawa, M.

    2000-01-01

    The ITER Management Advisory Committee (MAC) Meeting was held on 28 June 2000 in Moskow, Russia. The main topics were the consideration of the report by the director on the ITER EDA status, the review of the work program, the review of the joint fund, the review of a schedule of ITER meetings and initial discussion and consideration on the disposition of R and D hardware and facilities and other dispositions relating to the termination of the EDA

  1. Detomidine reduces isoflurane anesthetic requirement (MAC) in horses.

    Science.gov (United States)

    Steffey, Eugene P; Pascoe, Peter J

    2002-10-01

    To quantitate the dose- and time-related magnitude of the anesthetic sparing effect of, and selected physiological responses to detomidine during isoflurane anesthesia in horses. Randomized cross-over study. Three, healthy, young adult horses weighing 485 ± 14 kg. Horses were anesthetized on two occasions to determine the minimum alveolar concentration (MAC) of isoflurane in O 2 and then to measure the anesthetic sparing effect (time-related MAC reduction) following IV detomidine (0.03 and 0.06 mg kg -1 ). Selected common measures of cardiopulmonary function, blood glucose and urinary output were also recorded. Isoflurane MAC was 1.44 ± 0.07% (mean ± SEM). This was reduced by 42.8 ± 5.4% and 44.8 ± 3.0% at 83 ± 23 and 125 ± 36 minutes, respectively, following 0.03 and 0.06 mg kg -1 , detomidine. The MAC reduction was detomidine dose- and time-dependent. There was a tendency for mild cardiovascular and respiratory depression, especially following the higher detomidine dose. Detomidine increased both blood glucose and urine flow; the magnitude of these changes was time- and dose-dependent CONCLUSIONS: Detomidine reduces anesthetic requirement for isoflurane and increases blood glucose concentration and urine flow in horses. These changes were dose- and time-related. The results imply potent anesthetic sparing actions by detomidine. The detomidine-related increased urine flow should be considered in designing anesthetic protocols for individual horses. Copyright © 2002 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

  2. Performance of MAC protocols in beaconing Mobile Adhoc Multibroadcast Networks

    OpenAIRE

    Rico García, Cristina; Lehner, Andreas; Robertson, Patrick; Strang, Thomas

    2010-01-01

    The investigation of infrastructureless safety applications in dierent transportation systems is a hot research topic. The nodes in thevnetwork are designed to advertise to the rest of the nodes informationabout the current traffic situation by means of short beacon messages containing speed, direction, positions and other relevant safety information. The scheduling should be organized by the MAC layer so that the transmitted messages arrive successfully as soon as possible at the recei...

  3. LHC@home online tutorial for Mac users - recording

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    A step-by-step online tutorial about LHC@home for Mac users by Alexandre Racine. It contains detailed instructions on how-to-join this volunteer computing project.  There are 3 screen capture videos with the real installation process accelerated attached to the event page. This 5' video is linked from http://lhcathome.web.cern.ch/join-us Also from the CDS e-learning category.

  4. MacWilliams Identity for M-Spotty Weight Enumerator

    Science.gov (United States)

    Suzuki, Kazuyoshi; Fujiwara, Eiji

    M-spotty byte error control codes are very effective for correcting/detecting errors in semiconductor memory systems that employ recent high-density RAM chips with wide I/O data (e.g., 8, 16, or 32bits). In this case, the width of the I/O data is one byte. A spotty byte error is defined as random t-bit errors within a byte of length b bits, where 1 le t ≤ b. Then, an error is called an m-spotty byte error if at least one spotty byte error is present in a byte. M-spotty byte error control codes are characterized by the m-spotty distance, which includes the Hamming distance as a special case for t =1 or t = b. The MacWilliams identity provides the relationship between the weight distribution of a code and that of its dual code. The present paper presents the MacWilliams identity for the m-spotty weight enumerator of m-spotty byte error control codes. In addition, the present paper clarifies that the indicated identity includes the MacWilliams identity for the Hamming weight enumerator as a special case.

  5. MacA, a periplasmic membrane fusion protein of the macrolide transporter MacAB-TolC, binds lipopolysaccharide core specifically and with high affinity.

    Science.gov (United States)

    Lu, Shuo; Zgurskaya, Helen I

    2013-11-01

    The Escherichia coli MacAB-TolC transporter has been implicated in efflux of macrolide antibiotics and secretion of enterotoxin STII. In this study, we found that purified MacA, a periplasmic membrane fusion protein, contains one tightly bound rough core lipopolysaccharide (R-LPS) molecule per MacA molecule. R-LPS was bound specifically to MacA protein with affinity exceeding that of polymyxin B. Sequence analyses showed that MacA contains two high-density clusters of positively charged amino acid residues located in the cytoplasmic N-terminal domain and the periplasmic C-terminal domain. Substitutions in the C-terminal cluster reducing the positive-charge density completely abolished binding of R-LPS. At the same time, these substitutions significantly reduced the functionality of MacA in the protection of E. coli against macrolides in vivo and in the in vitro MacB ATPase stimulation assays. Taken together, our results suggest that R-LPS or a similar glycolipid is a physiological substrate of MacAB-TolC.

  6. TMAC: Timestamp-Ordered MAC Protocol for Wireless Mesh Networks

    KAUST Repository

    Nawab, Faisal

    2011-05-01

    Wireless Mesh Networks (WMNs) have emerged to meet a need for a self-organized and self-configured multi-hop wireless network infrastructure. Low cost infrastructure and ease of deployment have made WMNs an attractive technology for last mile access. However, 802.11 based WMNs are subject to serious fairness issues. With backlogged TCP traffic, nodes which are two or more hops away from the gateway are subject to starvation, while the one-hop away node saturates the channel with its own local traffic. We study the interactions of TCP and IEEE 802.11 MAC in WMNs to aid us in understanding and overcoming the unfairness problem. We propose a Markov chain to capture the behavior of TCP sessions, particularly the impact on network throughput performance due to the effect of queue utilization and packet relaying. A closed form solution is derived to numerically derive the throughput. Based on the developed model, we propose a distributed MAC protocol called Timestamp-ordered MAC (TMAC), aiming to alleviate the unfairness problem in WMNs via a manipulative per-node scheduling mechanism which takes advantage of the age of each packet as a priority metric. Simulation is conducted to validate our model and to illustrate the fairness characteristics of TMAC. Our results show that TMAC achieves excellent resource allocation fairness while maintaining above 90% of maximum link capacity in parking lot and large grid topologies. Our work illuminates the factors affecting TCP fairness in WMNs. Our theoretical and empirical findings can be used in future research to develop more fairness-aware protocols for WMNs.

  7. Intelligent Cooperative MAC Protocol for Balancing Energy Consumption

    Science.gov (United States)

    Wu, S.; Liu, K.; Huang, B.; Liu, F.

    To extend the lifetime of wireless sensor networks, we proposed an intelligent balanced energy consumption cooperative MAC protocol (IBEC-CMAC) based on the multi-node cooperative transmission model. The protocol has priority to access high-quality channels for reducing energy consumption of each transmission. It can also balance the energy consumption among cooperative nodes by using high residual energy nodes instead of excessively consuming some node's energy. Simulation results show that IBEC-CMAC can obtain longer network lifetime and higher energy utilization than direct transmission.

  8. Mac configuration management at the Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Marcus, Allan B [Los Alamos National Laboratory

    2010-01-01

    The Los Alamos National Laboratory (LANL) had a need for central configuration management of non-Windows computers. LANL has three to five thousand Macs and an equal number of Linux based systems. The primary goal was to be able to inventory all non-windows systems and patch Mc OS X systems. LANL examined a number of commercial and open source solutions and ultimately selected Puppet. This paper will discuss why we chose Puppet, how we implemented it, and some lessons we learned along the way.

  9. An Optimized Virtual Scheme for Reducing Collisions in MAC Layer

    OpenAIRE

    M. Sivakumar; S. Saravanan

    2015-01-01

    The main function of Medium Access Control (MAC) is to share the channel efficiently between all nodes. In the real-time scenario, there will be certain amount of wastage in bandwidth due to back-off periods. More bandwidth will be wasted in idle state if the back-off period is very high and collision may occur if the back-off period is small. So, an optimization is needed for this problem. The main objective of the work is to reduce delay due to back-off period thereby reducing collision and...

  10. MAC/FAC: A Model of Similarity-Based Retrieval

    Science.gov (United States)

    1994-10-01

    Grapes (0.28) 327 Sour Grapes, analog The Taming of the Shrew (0.22), Merry Wives 251 (0.18), S[11 stories], Sour Grapes (-0.19) Sour Grapes, literal... The Institute for the 0 1 Learning Sciences Northwestern University CD• 00 MAC/FAC: A MODEL OF SIMILARITY-BASED RETRIEVAL Kenneth D. Forbus Dedre...Gentner Keith Law Technical Report #59 • October 1994 94-35188 wit Establisthed in 1989 with the support of Andersen Consulting Form Approved REPORT

  11. ETEEM- Extended Traffic Aware Energy Efficient MAC Scheme for WSNs

    OpenAIRE

    Younas Khan; Sheeraz Ahmed; Fakhri Alam Khan; Imran Ahmad; Saqib Shahid Rahim; M. Irfan Khattak

    2016-01-01

    Idle listening issue arises when a sensor node listens to medium despite the absence of data which results in consumption of energy. ETEEM is a variant of Traffic Aware Energy Efficient MAC protocol (TEEM) which focuses on energy optimization due to reduced idle listening time and much lesser overhead on energy sources. It uses a novel scheme for using idle listening time of sensor nodes. The nodes are only active for small amount of time and most of the time, will be in sleep mode when no da...

  12. Planeamiento Estratégico para Rímac Seguros

    OpenAIRE

    Alvitez Muñoz, Julio César; Esquivel Porras, César Augusto; Slocovich Salcedo, Erick Rodolfo

    2005-01-01

    El presente trabajo desarrolla una propuesta de valor en el ámbito del mercado de seguros de vida para ser implementada en Rímac Seguros, permitiendo asegurar a la empresa la sostenibilidad de su liderazgo a través del incremento de su participación en el mercado y la fidelización de sus clientes. Las condiciones en las que se desarrolla la industria de seguros en el mundo y en el Perú en particular, como la séptima en volumen de primas a nivel latinoamericano ofrece un mercado reducido ba...

  13. Power-Controlled MAC Protocols with Dynamic Neighbor Prediction for Ad hoc Networks

    Institute of Scientific and Technical Information of China (English)

    LI Meng; ZHANG Lin; XIAO Yong-kang; SHAN Xiu-ming

    2004-01-01

    Energy and bandwidth are the scarce resources in ad hoc networks because most of the mobile nodes are battery-supplied and share the exclusive wireless medium. Integrating the power control into MAC protocol is a promising technique to fully exploit these precious resources of ad hoc wireless networks. In this paper, a new intelligent power-controlled Medium Access Control (MAC) (iMAC) protocol with dynamic neighbor prediction is proposed. Through the elaborate design of the distributed transmit-receive strategy of mobile nodes, iMAC greatly outperforms the prevailing IEEE 802.11 MAC protocols in not only energy conservation but also network throughput. Using the Dynamic Neighbor Prediction (DNP), iMAC performs well in mobile scenes. To the best of our knowledge, iMAC is the first protocol that considers the performance deterioration of power-controlled MAC protocols in mobile scenes and then proposes a solution. Simulation results indicate that DNP is important and necessary for power-controlled MAC protocols in mobile ad hoc networks.

  14. A Fair Cooperative MAC Protocol in IEEE 802.11 WLAN

    Directory of Open Access Journals (Sweden)

    Seyed Davoud Mousavi

    2018-05-01

    Full Text Available Cooperative communication techniques have recently enabled wireless technologies to overcome their challenges. The main objective of these techniques is to improve resource allocation. In this paper, we propose a new protocol in medium access control (MAC of the IEEE 802.11 standard. In our new protocol, which is called Fair Cooperative MAC (FC-MAC, every relay node participates in cooperation proportionally to its provided cooperation gain. This technique improves network resource allocation by exploiting the potential capacity of all relay candidates. Simulation results demonstrate that the FC-MAC protocol presents better performance in terms of throughput, fairness, and network lifetime.

  15. Learning Microsoft Excel 2011 for Mac video training DVD

    CERN Document Server

    Vaccaro, Guy

    2011-01-01

    In this video tutorial for Microsoft Excel 2011 For Mac, expert author Guy Vaccaro teaches you to effectively utilize the features and functions of Excel through project based learning. You will complete various projects, and along they way learn to leverage the power of the most important features Excel 2011 has to offer the Mac user. Starting your training course with the creation of a spreadsheet to record and monitor sales data, you will learn the basics of what you can do with a spreadsheet. You will then move on to creating a Profit and Loss report, learning formulas along the way. Moving to score sheets for a sports day, you will discover conditional based formatting, lookups, and more. You then create a functional expense claim form, advancing your Excel expertise. Moving on to a sales contact management sheet, you will discover how you can manipulate text, and even create mail merges from Excel. Finally, you will utilize all your knowledge thus far to create a sales report, including charts, pivot ta...

  16. Autonomous Power Control MAC Protocol for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Battery energy limitation has become a performance bottleneck for mobile ad hoc networks. IEEE 802.11 has been adopted as the current standard MAC protocol for ad hoc networks. However, it was developed without considering energy efficiency. To solve this problem, many modifications on IEEE 802.11 to incorporate power control have been proposed in the literature. The main idea of these power control schemes is to use a maximum possible power level for transmitting RTS/CTS and the lowest acceptable power for sending DATA/ACK. However, these schemes may degrade network throughput and reduce the overall energy efficiency of the network. This paper proposes autonomous power control MAC protocol (APCMP, which allows mobile nodes dynamically adjusting power level for transmitting DATA/ACK according to the distances between the transmitter and its neighbors. In addition, the power level for transmitting RTS/CTS is also adjustable according to the power level for DATA/ACK packets. In this paper, the performance of APCMP protocol is evaluated by simulation and is compared with that of other protocols.

  17. Is Kyoto Fatally Flawed? An Analysis with MacGEM

    International Nuclear Information System (INIS)

    Eyckmans, J.; Van Regemorter, D.; Van Steenberghe, V.

    2002-06-01

    In this paper we present some numerical simulations with the MacGEM model to evaluate the consequences of the recent Marrakesh agreements and the defection of the USA for the Kyoto Protocol. MacGEM is a global marginal abatement cost model for carbon emissions from fossil fuel use based on the GEM-E3-World general equilibrium. Nonparticipation of the USA causes the equilibrium carbon price in Annex B countries to fall by approximately 50% since an important share of permit demand falls out. Carbon sinks enhancement activities enable Parties to fulfil their reduction commitment at lower compliance costs and cause the equilibrium permit price to decrease by 40%. Finally, it is shown that the former Soviet Union and central European countries have substantial monopoly power in the Kyoto carbon permit market. We conclude that the recent accords have eroded completely the Kyoto Protocol's emission targets but that they have the merit to have saved the international climate change negotiation framework

  18. C-MAC compared with direct laryngoscopy for intubation in patients with cervical spine immobilization: A manikin trial.

    Science.gov (United States)

    Smereka, Jacek; Ladny, Jerzy R; Naylor, Amanda; Ruetzler, Kurt; Szarpak, Lukasz

    2017-08-01

    The aim of this study was to compare C-MAC videolaryngoscopy with direct laryngoscopy for intubation in simulated cervical spine immobilization conditions. The study was designed as a prospective randomized crossover manikin trial. 70 paramedics with immobilization (Scenario A); manual inline cervical immobilization (Scenario B); cervical immobilization using cervical extraction collar (Scenario C). Scenario A: Nearly all participants performed successful intubations with both MAC and C-MAC on the first attempt (95.7% MAC vs. 100% C-MAC), with similar intubation times (16.5s MAC vs. 18s C-MAC). Scenario B: The results with C-MAC were significantly better than those with MAC (pimmobilization. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Petrology and U-PB geochronology of the Robertson River Igneous Suite, Blue Ridge province, Virginia - Evidence for multistage magmatism associated witn an early episode of Laurentian rifting

    Science.gov (United States)

    Tollo, R.P.; Aleinikoff, J.N.

    1996-01-01

    The Late Neoproterozoic (735-702 Ma) Robertson River Igneous Suite includes at least eight plutons ranging in composition from syenogranite to alkali feldspar granite to alkali feldspar syenite. These plutons intruded Mesoproterozoic (1.2-1.0 Ga) gneissic basement of the Blue Ridge anticlinorium in northern and central Virginia during an early episode of Laurentian rifting. Robertson River plutons range in composition from metaluminous to peralkaline and, relative to other granite types, exhibit compositional characteristics of A-type granitoids including (1) marked enrichment in Nb, Zr, Y, REE (except Eu), and Ga, (2) high Ga/Al and FeO(total)/MgO, and (3) depletion of Ba and Sr. High Ga/Al ratios are particularly diagnostic of the suite and serve as an effective discriminant between originally metaluminous and peralkaline bulk compositions, providing a useful proxy for widely used indicators based on major elements that are prone to remobilization. U-Pb isotopic analyses of zircons indicate that the suite was emplaced in two pulses, occurring at 735 to 722 and 706 to 702 Ma. Metaluminous magmas were emplaced during both pulses, formed most of the main batholith, and fractionated as independent, time-correlative groups. Peralkaline magmas were emplaced only during the final pulse, formed a volcanic center that erupted unknown quantities of rhyolite, and experienced a style of fractionation similar to the metaluminous types. Differences in Ce/Nb, Y/Nb, and Yb/Ta ratios suggest that the metaluminous and peralkaline magmas were derived from different sources. The Robertson River Igneous Suite is part of a regional group of Late Neoproterozoic (760-700 Ma) plutons including at least 20 other A-type granitoid bodies exposed throughout the Laurentian terrane of Virginia and northwestern North Carolina. Like the Robertson River, most of the other granitoids are metaluminous in composition, typically form multi-intrusive, elongate plutons, and are not geographically

  20. Accuracy of the MacArthur competence assessment tool for clinical research (MacCAT-CR) for measuring children's competence to consent to clinical research.

    Science.gov (United States)

    Hein, Irma M; Troost, Pieter W; Lindeboom, Robert; Benninga, Marc A; Zwaan, C Michel; van Goudoever, Johannes B; Lindauer, Ramón J L

    2014-12-01

    An objective assessment of children's competence to consent to research participation is currently not possible. Age limits for asking children's consent vary considerably between countries, and, to our knowledge, the correlation between competence and children's age has never been systematically investigated. To test a standardized competence assessment instrument for children by modifying the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR), to investigate its reliability and validity, and to examine the correlation of its assessment with age and estimate cutoff ages. This prospective study included children and adolescents aged 6 to 18 years in the inpatient and outpatient departments of allergology, gastroenterology, oncology, ophthalmology, and pulmonology from January 1, 2012, through January 1, 2014. Participants were eligible for clinical research studies, including observational studies and randomized clinical trials. Competence judgments by experts aware of the 4 relevant criteria-understanding, appreciation, reasoning, and choice-were used to establish the reference standard. The index test was the MacCAT-CR, which used a semistructured interview format. Interrater reliability, validity, and dimensionality of the MacCAT-CR and estimated cutoff ages for competence. Of 209 eligible patients, we included 161 (mean age, 10.6 years; 47.2% male). Good reproducibility of MacCAT-CR total and subscale scores was observed (intraclass correlation coefficient range, 0.68-0.92). We confirmed unidimensionality of the MacCAT-CR. By the reference standard, we judged 54 children (33.5%) to be incompetent; by the MacCAT-CR, 61 children (37.9%). Criterion-related validity of MacCAT-CR scores was supported by high overall accuracy in correctly classifying children as competent against the reference standard (area under the receiver operating characteristics curve, 0.78). Age was a good predictor of competence on the MacCAT-CR (area under the receiver

  1. Antimoulting Activity of Eremanthus erythropappus (DC. MacLeisch

    Directory of Open Access Journals (Sweden)

    Danielle Barbosa

    2012-06-01

    Resumo. Os extratos e metabólitos secundários de plantas podem agir como agentes tóxicos e inibidores do da alimentação e do desenvolvimento em insetos. Neste estudo foi utilizado Oncopeltus fasciatus (Dallas (Hemiptera como modelo experimental a fim de avaliar as atividades do extrato etanólico bruto e frações obtidos das flores ou caules de Eremanthus erythropappus (DC. MacLeisch (Asteraceae, na mortalidade e sobre o desenvolvimento do inseto. A fração butanólica obtida do extrato etanólico mostrou toxidade sobre as ninfas de O. fasciatus, bem como atividade de inibição do crescimento. Os resultados sugerem que a fração butanólica de E. erythropappus possui substâncias ativas sobre a fisiologia, crescimento e desenvolvimento de insetos.

  2. The Virtues of Scientific Practice: MacIntyre,

    Science.gov (United States)

    Hicks, Daniel J; Stapleford, Thomas A

    2016-09-01

    “Practice” has become a ubiquitous term in the history of science, and yet historians have not always reflected on its philosophical import and in particular on its potential connections with ethics. This essay draws on the work of the virtue ethicist Alasdair MacIntyre to develop a theory of “communal practices” and explore how such an approach can inform the history of science, including allegations about the corruption of science by wealth or power, consideration of scientific ethics or “moral economies,” the role of values in science, the ethical distinctiveness (or not) of scientific vocations, and the relationship between history of science and the practice of science itself.

  3. Rocket measurements of electron density irregularities during MAC/SINE

    Science.gov (United States)

    Ulwick, J. C.

    1989-01-01

    Four Super Arcas rockets were launched at the Andoya Rocket Range, Norway, as part of the MAC/SINE campaign to measure electron density irregularities with high spatial resolution in the cold summer polar mesosphere. They were launched as part of two salvos: the turbulent/gravity wave salvo (3 rockets) and the EISCAT/SOUSY radar salvo (one rocket). In both salvos meteorological rockets, measuring temperature and winds, were also launched and the SOUSY radar, located near the launch site, measured mesospheric turbulence. Electron density irregularities and strong gradients were measured by the rocket probes in the region of most intense backscatter observed by the radar. The electron density profiles (8 to 4 on ascent and 4 on descent) show very different characteristics in the peak scattering region and show marked spatial and temporal variability. These data are intercompared and discussed.

  4. MACS low-background doubly focusing neutron monochromator

    CERN Document Server

    Smee, S A; Scharfstein, G A; Qiu, Y; Brand, P C; Anand, D K; Broholm, C L

    2002-01-01

    A novel doubly focusing neutron monochromator has been developed as part of the Multi-Analyzer Crystal Spectrometer (MACS) at the NIST Center for Neutron Research. The instrument utilizes a unique vertical focusing element that enables active vertical and horizontal focusing with a large, 357-crystal (1428 cm sup 2), array. The design significantly reduces the amount of structural material in the beam path as compared to similar instruments. Optical measurements verify the excellent focal performance of the device. Analytical and Monte Carlo simulations predict that, when mounted at the NIST cold-neutron source, the device should produce a monochromatic beam (DELTA E=0.2 meV) with flux phi>10 sup 8 n/cm sup 2 s. (orig.)

  5. On PHY and MAC Performance in Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Higgins Henry

    2009-01-01

    Full Text Available Abstract This paper presents an empirical investigation on the performance of body implant communication using radio frequency (RF technology. In body implant communication, the electrical properties of the body influence the signal propagation in several ways. We use a Perspex body model (30 cm diameter, 80 cm height and 0.5 cm thickness filled with a liquid that mimics the electrical properties of the basic body tissues. This model is used to observe the effects of body tissue on the RF communication. We observe best performance at 3cm depth inside the liquid. We further present a simulation study of several low-power MAC protocols for an on-body sensor network and discuss the derived results. Also, the traditional preamble-based TMDA protocol is extended towards a beacon-based TDMA protocol in order to avoid preamble collision and to ensure low-power communication.

  6. On PHY and MAC Performance in Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sana Ullah

    2009-01-01

    Full Text Available This paper presents an empirical investigation on the performance of body implant communication using radio frequency (RF technology. In body implant communication, the electrical properties of the body influence the signal propagation in several ways. We use a Perspex body model (30 cm diameter, 80 cm height and 0.5 cm thickness filled with a liquid that mimics the electrical properties of the basic body tissues. This model is used to observe the effects of body tissue on the RF communication. We observe best performance at 3cm depth inside the liquid. We further present a simulation study of several low-power MAC protocols for an on-body sensor network and discuss the derived results. Also, the traditional preamble-based TMDA protocol is extended towards a beacon-based TDMA protocol in order to avoid preamble collision and to ensure low-power communication.

  7. 76 FR 71797 - Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Investments and...

    Science.gov (United States)

    2011-11-18

    ... diligence procedures that are required for investments, but we do not intend to change the fundamental... Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Investments and Liquidity... Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Investments and Liquidity Management AGENCY...

  8. A MacWilliams Identity for Convolutional Codes: The General Case

    OpenAIRE

    Gluesing-Luerssen, Heide; Schneider, Gert

    2008-01-01

    A MacWilliams Identity for convolutional codes will be established. It makes use of the weight adjacency matrices of the code and its dual, based on state space realizations (the controller canonical form) of the codes in question. The MacWilliams Identity applies to various notions of duality appearing in the literature on convolutional coding theory.

  9. A MacWilliams Identity for Convolutional Codes : The General Case

    NARCIS (Netherlands)

    Gluesing-Luerssen, Heide; Schneider, Gert

    A MacWilliams Identity for convolutional codes will be established. It makes use of the weight adjacency matrices of the code and its dual, based on state space realizations (the controller canonical form) of the codes in question. The MacWilliams Identity applies to various notions of duality

  10. Poincaré-MacMillan Equations of Motion for a Nonlinear Nonholonomic Dynamical System

    Science.gov (United States)

    Amjad, Hussain; Syed Tauseef, Mohyud-Din; Ahmet, Yildirim

    2012-03-01

    MacMillan's equations are extended to Poincaré's formalism, and MacMillan's equations for nonlinear nonholonomic systems are obtained in terms of Poincaré parameters. The equivalence of the results obtained here with other forms of equations of motion is demonstrated. An illustrative example of the theory is provided as well.

  11. Public Relations as "Practice": Applying the Theory of Alasdair MacIntyre.

    Science.gov (United States)

    Leeper, Roy V.; Leeper, Kathie A.

    2001-01-01

    Considers how public relation's search for a unifying theory may be fulfilled through application of Alasdair MacIntyre's concept of a "practice," a very specific and value-laden concept. Explores what it would mean to be a public relations practice in MacIntyre's concept of the term and argues that such an approach to public relations…

  12. 78 FR 5320 - Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Capital Planning

    Science.gov (United States)

    2013-01-25

    ... the business planning period a required discussion of how factors might impact Farmer Mac's current... discussion of any expected changes to Farmer Mac's business plan that are likely to have a material impact on... conditions that cause increases in delinquency rates caused by any variety of factors (e.g., widespread...

  13. Geochemistry and petrography of the MacAlpine Hills lunar meteorites

    Science.gov (United States)

    Lindstrom, Marilyn M.; Mckay, David S.; Wentworth, Susan J.; Martinez, Rene R.; Mittlefehldt, David W.; Wang, Ming-Sheng; Lipschutz, Michael E.

    1991-01-01

    MacAlpine Hills 88104 and 88105, anorthositic lunar meteorites recovered form the same area in Antartica, are characterized. Petrographic studies show that MAC88104/5 is a polymict breccia dominated by impact melt clasts. It is better classified as a fragmental breccia than a regolith breccia. The bulk composition is ferroan and highly aluminous (Al2O3-28 percent).

  14. Optimization and Verification of the TR-MAC Protocol for Wireless Sensor Networks

    NARCIS (Netherlands)

    Morshed, S.; Heijenk, Geert

    2015-01-01

    Energy-efficiency is an important requirement in the design of communication protocols for wireless sensor networks (WSN). TR-MAC is an energy-efficient medium access control (MAC) layer protocol for low power WSN that exploits transmitted-reference (TR) modulation in the physical layer. The

  15. THE EFFECT OF TEMPERATURE ON THE GROWTH OF MYCOBACTERIUM AVIUM COMPLEX (MAC) ORGANISMS

    Science.gov (United States)

    MAC organisms are able to grow, persist, and colonize in water distribution systems and may amplify in hospital hot water systems. This study examined the response of MAC organisms (M. avium, M. intracellulare, and MX) to a range of temperatures commonly associated with drinking...

  16. Scheduled MAC in Beacon Overlay Networks for Underwater Localization and Time-Synchronization

    NARCIS (Netherlands)

    van Kleunen, W.A.P.; Meratnia, Nirvana; Havinga, Paul J.M.

    2011-01-01

    In this article we introduce a MAC protocol designed for underwater localization and time-synchronisation. The MAC protocol assumes a network of static reference nodes and allows blind nodes to be localized by listening-only to the beacon messages. Such a system is known to be very scalable. We show

  17. Trust women to choose: a response to John a Robertson's 'Egg freezing and Egg banking: empowerment and alienation in assisted reproduction'.

    Science.gov (United States)

    Goold, Imogen

    2017-12-01

    In 'Egg Freezing and Egg Banking: Empowerment and Alienation in Assisted Reproduction', John A Robertson responds to the American Society of Reproductive Medicine's statement that oocyte preservation should no longer be considered an experimental treatment. He explores the implications of this development, focusing on the potentially empowering impact of oocyte preservation as a means for women to preserve their fertility. He also engages with concerns about the possibility that such a development may raise issues of alienation. He highlights some of the potential problems that may emerge as women gain the capacity to store and either donate or sell any eggs they do not need for their own reproductive purposes. Much of his paper is valuable and considered, but in places, his views rest on assumptions about women's attitudes to their fertility, understanding of the technology, and relationship with their gametes that are open to dispute. This paper teases out some of these assumptions and puts pressure on them by drawing on the growing body of data about what women actually do think and feel about fertility issues. It focuses on two of his main concerns-that social egg freezing may give women a false sense of security and that women may be harmed if a market in eggs leads to their alienation from their gametes. Via this response to Robertson, I aim to redress the tendency often seen in discussions around women, infertility, aging, and empowerment to unquestioningly accept what I argue are stereotypes and assumptions about women's views and capacity to reason.

  18. Identifying The Purchasing Power Parity of Indonesia Rupiah (IDR based on BIG MAC Index

    Directory of Open Access Journals (Sweden)

    Tongam Sihol Nababan

    2016-12-01

    Full Text Available The aim of this study is to identify : (1 profile of exchange rate and purchasing power parity of IDR against US $ based on Big Mac Index compared to the exchange rate of other countries, and (2 the position of the Big Mac Affordability of  Indonesia compared to other ASEAN countries. The results showed that based on Big Mac index during the period April 1998 up to January 2015, IDR exchange rate tends to be undervalued against the USA dollar. The cause of the currency tends to be in a position of undervalued due to the components of non-tradable have not been included in Big Mac index. The index of Big Mac Affordability indicates that there is a great disparity of income between Singapore and five other ASEAN countries. The purchasing power of the real income of the people in Singapore is nearly five times the real income of the people in Indonesia.

  19. Impact of MAC Delay on AUV Localization: Underwater Localization Based on Hyperbolic Frequency Modulation Signal.

    Science.gov (United States)

    Kim, Sungryul; Yoo, Younghwan

    2018-01-26

    Medium Access Control (MAC) delay which occurs between the anchor node's transmissions is one of the error sources in underwater localization. In particular, in AUV localization, the MAC delay significantly degrades the ranging accuracy. The Cramer-Rao Low Bound (CRLB) definition theoretically proves that the MAC delay significantly degrades the localization performance. This paper proposes underwater localization combined with multiple access technology to decouple the localization performance from the MAC delay. Towards this goal, we adopt hyperbolic frequency modulation (HFM) signal that provides multiplexing based on its good property, high-temporal correlation. Owing to the multiplexing ability of the HFM signal, the anchor nodes can transmit packets without MAC delay, i.e., simultaneous transmission is possible. In addition, the simulation results show that the simultaneous transmission is not an optional communication scheme, but essential for the localization of mobile object in underwater.

  20. Interference Analysis Status and Plans for Aeronautical Mobile Airport Communications System (AeroMACS)

    Science.gov (United States)

    Kerczewski, Robert J.; Wilson, Jeffrey D.

    2010-01-01

    Interference issues related to the operation of an aeronautical mobile airport communications system (AeroMACS) in the C-Band (specifically 5091-5150 MHz) is being investigated. The issue of primary interest is co-channel interference from AeroMACS into mobile-satellite system (MSS) feeder uplinks. The effort is focusing on establishing practical limits on AeroMACS transmissions from airports so that the threshold of interference into MSS is not exceeded. The analyses are being performed with the software package Visualyse Professional, developed by Transfinite Systems Limited. Results with omni-directional antennas and plans to extend the models to represent AeroMACS more accurately will be presented. These models should enable realistic analyses of emerging AeroMACS designs to be developed from NASA Test Bed, RTCA 223, and European results.

  1. Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs with Extended Service Range

    Science.gov (United States)

    Choi, Woo-Yong

    2011-11-01

    In this paper, we propose the efficient reliable multicast MAC protocol by which the AP (Access Point) can transmit reliably its multicast data frames to the recipients in the AP's one-hop or two-hop transmission range. The AP uses the STAs (Stations) that are directly associated with itself as the relays for the data delivery to the remote recipients that cannot be reached directly from itself. Based on the connectivity information among the recipients, the reliable multicast MAC protocol optimizes the number of the RAK (Request for ACK) frame transmissions in a reasonable computational time. Numerical examples show that our proposed MAC protocol significantly enhances the MAC performance compared with the BMMM (Batch Mode Multicast MAC) protocol that is extended to support the recipients that are in the AP's one-hop or two-hop transmission range in IEEE 802.11 wireless LANs.

  2. Functional characterization of the copper transcription factor AfMac1 from Aspergillus fumigatus.

    Science.gov (United States)

    Park, Yong-Sung; Kim, Tae-Hyoung; Yun, Cheol-Won

    2017-07-03

    Although copper functions as a cofactor in many physiological processes, copper overload leads to harmful effects in living cells. Thus, copper homeostasis is tightly regulated. However, detailed copper metabolic pathways have not yet been identified in filamentous fungi. In this report, we investigated the copper transcription factor AfMac1 ( A spergillus f umigatus Mac1 homolog) and identified its regulatory mechanism in A. fumigatus AfMac1 has domains homologous to the DNA-binding and copper-binding domains of Mac1 from Saccharomyces cerevisiae , and AfMac1 efficiently complemented Mac1 in S. cerevisiae Expression of Afmac1 resulted in CTR1 up-regulation, and mutation of the DNA-binding domain of Afmac1 failed to activate CTR1 expression in S. cerevisiae The Afmac1 deletion strain of A. fumigatus failed to grow in copper-limited media, and its growth was restored by introducing ctrC We found that AfMac1 specifically bound to the promoter region of ctrC based on EMSA. The AfMac1-binding motif 5'-TGTGCTCA-3' was identified from the promoter region of ctrC , and the addition of mutant ctrC lacking the AfMac1-binding motif failed to up-regulate ctrC in A. fumigatus Furthermore, deletion of Afmac1 significantly reduced strain virulence and activated conidial killing activity by neutrophils and macrophages. Taken together, these results suggest that AfMac1 is a copper transcription factor that regulates cellular copper homeostasis in A. fumigatus . © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  3. Antibiotic Resistance Mediated by the MacB ABC Transporter Family: A Structural and Functional Perspective

    Directory of Open Access Journals (Sweden)

    Nicholas P. Greene

    2018-05-01

    Full Text Available The MacB ABC transporter forms a tripartite efflux pump with the MacA adaptor protein and TolC outer membrane exit duct to expel antibiotics and export virulence factors from Gram-negative bacteria. Here, we review recent structural and functional data on MacB and its homologs. MacB has a fold that is distinct from other structurally characterized ABC transporters and uses a unique molecular mechanism termed mechanotransmission. Unlike other bacterial ABC transporters, MacB does not transport substrates across the inner membrane in which it is based, but instead couples cytoplasmic ATP hydrolysis with transmembrane conformational changes that are used to perform work in the extra-cytoplasmic space. In the MacAB-TolC tripartite pump, mechanotransmission drives efflux of antibiotics and export of a protein toxin from the periplasmic space via the TolC exit duct. Homologous tripartite systems from pathogenic bacteria similarly export protein-like signaling molecules, virulence factors and siderophores. In addition, many MacB-like ABC transporters do not form tripartite pumps, but instead operate in diverse cellular processes including antibiotic sensing, cell division and lipoprotein trafficking.

  4. Antibiotic Resistance Mediated by the MacB ABC Transporter Family: A Structural and Functional Perspective

    Science.gov (United States)

    Greene, Nicholas P.; Kaplan, Elise; Crow, Allister; Koronakis, Vassilis

    2018-01-01

    The MacB ABC transporter forms a tripartite efflux pump with the MacA adaptor protein and TolC outer membrane exit duct to expel antibiotics and export virulence factors from Gram-negative bacteria. Here, we review recent structural and functional data on MacB and its homologs. MacB has a fold that is distinct from other structurally characterized ABC transporters and uses a unique molecular mechanism termed mechanotransmission. Unlike other bacterial ABC transporters, MacB does not transport substrates across the inner membrane in which it is based, but instead couples cytoplasmic ATP hydrolysis with transmembrane conformational changes that are used to perform work in the extra-cytoplasmic space. In the MacAB-TolC tripartite pump, mechanotransmission drives efflux of antibiotics and export of a protein toxin from the periplasmic space via the TolC exit duct. Homologous tripartite systems from pathogenic bacteria similarly export protein-like signaling molecules, virulence factors and siderophores. In addition, many MacB-like ABC transporters do not form tripartite pumps, but instead operate in diverse cellular processes including antibiotic sensing, cell division and lipoprotein trafficking. PMID:29892271

  5. A Cross-Layer Duty Cycle MAC Protocol Supporting a Pipeline Feature for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Young-Chon Kim

    2011-05-01

    Full Text Available Although the conventional duty cycle MAC protocols for Wireless Sensor Networks (WSNs such as RMAC perform well in terms of saving energy and reducing end-to-end delivery latency, they were designed independently and require an extra routing protocol in the network layer to provide path information for the MAC layer. In this paper, we propose a new cross-layer duty cycle MAC protocol with data forwarding supporting a pipeline feature (P-MAC for WSNs. P-MAC first divides the whole network into many grades around the sink. Each node identifies its grade according to its logical hop distance to the sink and simultaneously establishes a sleep/wakeup schedule using the grade information. Those nodes in the same grade keep the same schedule, which is staggered with the schedule of the nodes in the adjacent grade. Then a variation of the RTS/CTS handshake mechanism is used to forward data continuously in a pipeline fashion from the higher grade to the lower grade nodes and finally to the sink. No extra routing overhead is needed, thus increasing the network scalability while maintaining the superiority of duty-cycling. The simulation results in OPNET show that P-MAC has better performance than S-MAC and RMAC in terms of packet delivery latency and energy efficiency.

  6. A Priority-Based Adaptive MAC Protocol for Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Sabin Bhandari

    2016-03-01

    Full Text Available In wireless body area networks (WBANs, various sensors and actuators are placed on/inside the human body and connected wirelessly. WBANs have specific requirements for healthcare and medical applications, hence, standard protocols like the IEEE 802.15.4 cannot fulfill all the requirements. Consequently, many medium access control (MAC protocols, mostly derived from the IEEE 802.15.4 superframe structure, have been studied. Nevertheless, they do not support a differentiated quality of service (QoS for the various forms of traffic coexisting in a WBAN. In particular, a QoS-aware MAC protocol is essential for WBANs operating in the unlicensed Industrial, Scientific, and Medical (ISM bands, because different wireless services like Bluetooth, WiFi, and Zigbee may coexist there and cause severe interference. In this paper, we propose a priority-based adaptive MAC (PA-MAC protocol for WBANs in unlicensed bands, which allocates time slots dynamically, based on the traffic priority. Further, multiple channels are effectively utilized to reduce access delays in a WBAN, in the presence of coexisting systems. Our performance evaluation results show that the proposed PA-MAC outperforms the IEEE 802.15.4 MAC and the conventional priority-based MAC in terms of the average transmission time, throughput, energy consumption, and data collision ratio.

  7. A Priority-Based Adaptive MAC Protocol for Wireless Body Area Networks.

    Science.gov (United States)

    Bhandari, Sabin; Moh, Sangman

    2016-03-18

    In wireless body area networks (WBANs), various sensors and actuators are placed on/inside the human body and connected wirelessly. WBANs have specific requirements for healthcare and medical applications, hence, standard protocols like the IEEE 802.15.4 cannot fulfill all the requirements. Consequently, many medium access control (MAC) protocols, mostly derived from the IEEE 802.15.4 superframe structure, have been studied. Nevertheless, they do not support a differentiated quality of service (QoS) for the various forms of traffic coexisting in a WBAN. In particular, a QoS-aware MAC protocol is essential for WBANs operating in the unlicensed Industrial, Scientific, and Medical (ISM) bands, because different wireless services like Bluetooth, WiFi, and Zigbee may coexist there and cause severe interference. In this paper, we propose a priority-based adaptive MAC (PA-MAC) protocol for WBANs in unlicensed bands, which allocates time slots dynamically, based on the traffic priority. Further, multiple channels are effectively utilized to reduce access delays in a WBAN, in the presence of coexisting systems. Our performance evaluation results show that the proposed PA-MAC outperforms the IEEE 802.15.4 MAC and the conventional priority-based MAC in terms of the average transmission time, throughput, energy consumption, and data collision ratio.

  8. McMAC: towards a MAC protocol with multi-constrained QoS provisioning for diverse traffic in Wireless Body Area Networks.

    Science.gov (United States)

    Monowar, Muhammad Mostafa; Hassan, Mohammad Mehedi; Bajaber, Fuad; Al-Hussein, Musaed; Alamri, Atif

    2012-11-12

    The emergence of heterogeneous applications with diverse requirements for resource-constrained Wireless Body Area Networks (WBANs) poses significant challenges for provisioning Quality of Service (QoS) with multi-constraints (delay and reliability) while preserving energy efficiency. To address such challenges, this paper proposes McMAC,a MAC protocol with multi-constrained QoS provisioning for diverse traffic classes in WBANs. McMAC classifies traffic based on their multi-constrained QoS demands and introduces a novel superframe structure based on the "transmit-whenever-appropriate"principle, which allows diverse periods for diverse traffic classes according to their respective QoS requirements. Furthermore, a novel emergency packet handling mechanism is proposedto ensure packet delivery with the least possible delay and the highest reliability. McMAC is also modeled analytically, and extensive simulations were performed to evaluate its performance. The results reveal that McMAC achieves the desired delay and reliability guarantee according to the requirements of a particular traffic class while achieving energy efficiency.

  9. MAC Version 3.2, MBA Version 1.3 acceptance test summary report

    International Nuclear Information System (INIS)

    Russell, V.K.

    1994-01-01

    The K Basins Materials Accounting (MAC) and Materials Balance (MBA) programs had the Paradox Conversion to 4.0 ATP run to check out the systems. This report describes the results of the test and provides the signoff sheets associated with the testing. The test primarily concentrated on verifying that MAC and MBA software would run properly in the Paradox 4.0 environment. Changes in the MAC and MBA programs were basically limited to superficial items needed to accommodate the enhanced method of execution

  10. Learn AppleScript The Comprehensive Guide to Scripting and Automation on MAC OS X

    CERN Document Server

    Rosenthal, Hanaan

    2009-01-01

    AppleScript is an English-like, easy-to-understand scripting language built into every Mac. AppleScript can automate hundreds of AppleScriptable applications, performing tasks both large and small, complex and simple. Learn AppleScript: The Comprehensive Guide to Scripting and Automation on Mac OS X, Third Edition has been completely updated for Mac OS X Snow Leopard. It's all here, with an emphasis on practical information that will help you solve any automation problem-from the most mundane repetitive tasks to highly integrated workflows of complex systems. * Friendly enough for beginners, d

  11. Are hamburgers harmless? : the Big Mac Index in the twenty-first century

    OpenAIRE

    Soo, Kwok Tong

    2016-01-01

    We make use of The Economist’s Big Mac Index (BMI) to investigate the Law of One Price (LOP) and whether the BMI can be used to predict future exchange rate and price changes. Deviations from Big Mac parity decay quickly, in approximately 1 year. The BMI is a better predictor of relative price changes than of exchange rate changes, and performs best when predicting a depreciation of a currency relative to the US dollar. Convergence to Big Mac parity occurs more rapidly for currencies with som...

  12. Identifying The Purchasing Power Parity of Indonesia Rupiah (IDR) based on BIG MAC Index

    OpenAIRE

    Tongam Sihol Nababan

    2016-01-01

    The aim of this study is to identify : (1) profile of exchange rate and purchasing power parity of IDR against US $ based on Big Mac Index compared to the exchange rate of other countries, and (2) the position of the Big Mac Affordability of Indonesia compared to other ASEAN countries. The results showed that based on Big Mac index during the period April 1998 up to January 2015, IDR exchange rate tends to be undervalued against the USA dollar. The cause of the currency tends to be in a posi...

  13. MAC Protocol for Ad Hoc Networks Using a Genetic Algorithm

    Science.gov (United States)

    Elizarraras, Omar; Panduro, Marco; Méndez, Aldo L.

    2014-01-01

    The problem of obtaining the transmission rate in an ad hoc network consists in adjusting the power of each node to ensure the signal to interference ratio (SIR) and the energy required to transmit from one node to another is obtained at the same time. Therefore, an optimal transmission rate for each node in a medium access control (MAC) protocol based on CSMA-CDMA (carrier sense multiple access-code division multiple access) for ad hoc networks can be obtained using evolutionary optimization. This work proposes a genetic algorithm for the transmission rate election considering a perfect power control, and our proposition achieves improvement of 10% compared with the scheme that handles the handshaking phase to adjust the transmission rate. Furthermore, this paper proposes a genetic algorithm that solves the problem of power combining, interference, data rate, and energy ensuring the signal to interference ratio in an ad hoc network. The result of the proposed genetic algorithm has a better performance (15%) compared to the CSMA-CDMA protocol without optimizing. Therefore, we show by simulation the effectiveness of the proposed protocol in terms of the throughput. PMID:25140339

  14. MAC Protocol for Ad Hoc Networks Using a Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Omar Elizarraras

    2014-01-01

    Full Text Available The problem of obtaining the transmission rate in an ad hoc network consists in adjusting the power of each node to ensure the signal to interference ratio (SIR and the energy required to transmit from one node to another is obtained at the same time. Therefore, an optimal transmission rate for each node in a medium access control (MAC protocol based on CSMA-CDMA (carrier sense multiple access-code division multiple access for ad hoc networks can be obtained using evolutionary optimization. This work proposes a genetic algorithm for the transmission rate election considering a perfect power control, and our proposition achieves improvement of 10% compared with the scheme that handles the handshaking phase to adjust the transmission rate. Furthermore, this paper proposes a genetic algorithm that solves the problem of power combining, interference, data rate, and energy ensuring the signal to interference ratio in an ad hoc network. The result of the proposed genetic algorithm has a better performance (15% compared to the CSMA-CDMA protocol without optimizing. Therefore, we show by simulation the effectiveness of the proposed protocol in terms of the throughput.

  15. Emergency Handling for MAC Protocol in Human Body Communication

    Directory of Open Access Journals (Sweden)

    Kwon Youngmi

    2011-01-01

    Full Text Available The human body communication (HBC is a technology that enables short range data communication using the human body as a medium, like an electrical wire. Thus it removes the need for a traditional antenna. HBC may be used as a type of data communication in body area network (BAN, while the devices are being in contact with body. One of important issues in BAN is an emergency alarm because it may be closely related to human life. For emergency data communication, the most critical factor is the time constraint. IEEE 802.15.6 specifies that the emergency alarm for the BAN must be notified in less than 1 sec and must provide prioritization mechanisms for emergency traffic and notification. As one type of BAN, the HBC must follow this recommendation, too. Existing emergency handling methods in BAN are based on the carrier sensing capability on radio frequencies to detect the status of channels. However, PHY protocol in HBC does not provide the carrier sensing. So the previous methods are not well suitable for HBC directly. Additionally, in the environment that the emergency rate is very low, the allocation of dedicated slot(s for emergency in each superframe is very wasteful. In this work, we proposed specific emergency handling operation for human body communication's medium access control (HBC-MAC protocol to meet the emergency requirements for BAN. We also showed the optimal number of emergency slots for the various combinations of beacon intervals and emergency rates.

  16. Bit Level Synchronized MAC Protocol for Multireader RFID Networks

    Directory of Open Access Journals (Sweden)

    Namboodiri Vinod

    2010-01-01

    Full Text Available The operation of multiple RFID readers in close proximity results in interference between the readers. This issue is termed the reader collision problem and cannot always be solved by assigning them to different frequency channels due to technical and regulatory limitations. The typical solution is to separate the operation of such readers across time. This sequential operation, however, results in a long delay to identify all tags. We present a bit level synchronized (BLSync MAC protocol for multi-reader RFID networks that allows multiple readers to operate simultaneously on the same frequency channel. The BLSync protocol solves the reader collision problem by allowing all readers to transmit the same query at the same time. We analyze the performance of using the BLSync protocol and demonstrate benefits of 40%–50% in terms of tag reading delay for most settings. The benefits of BLSync, first demonstrated through analysis, are then validated and quantified through simulations on realistic reader-tag layouts.

  17. LAMAN: Load Adaptable MAC for Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Realp Marc

    2005-01-01

    Full Text Available In mobile ad hoc radio networks, mechanisms on how to access the radio channel are extremely important in order to improve network efficiency. In this paper, the load adaptable medium access control for ad hoc networks (LAMAN protocol is described. LAMAN is a novel decentralized multipacket MAC protocol designed following a cross-layer approach. Basically, this protocol is a hybrid CDMA-TDMA-based protocol that aims at throughput maximization in multipacket communication environments by efficiently combining contention and conflict-free protocol components. Such combination of components is used to adapt the nodes' access priority to changes on the traffic load while, at the same time, accounting for the multipacket reception (MPR capability of the receivers. A theoretical analysis of the system is developed presenting closed expressions of network throughput and packet delay. By simulations the validity of our analysis is shown and the performances of a LAMAN-based system and an Aloha-CDMA-based one are compared.

  18. Trust women to choose: a response to John a Robertson's ‘Egg freezing and Egg banking: empowerment and alienation in assisted reproduction’†

    Science.gov (United States)

    2017-01-01

    Abstract In ‘Egg Freezing and Egg Banking: Empowerment and Alienation in Assisted Reproduction’, John A Robertson responds to the American Society of Reproductive Medicine's statement that oocyte preservation should no longer be considered an experimental treatment. He explores the implications of this development, focusing on the potentially empowering impact of oocyte preservation as a means for women to preserve their fertility. He also engages with concerns about the possibility that such a development may raise issues of alienation. He highlights some of the potential problems that may emerge as women gain the capacity to store and either donate or sell any eggs they do not need for their own reproductive purposes. Much of his paper is valuable and considered, but in places, his views rest on assumptions about women's attitudes to their fertility, understanding of the technology, and relationship with their gametes that are open to dispute. This paper teases out some of these assumptions and puts pressure on them by drawing on the growing body of data about what women actually do think and feel about fertility issues. It focuses on two of his main concerns—that social egg freezing may give women a false sense of security and that women may be harmed if a market in eggs leads to their alienation from their gametes. Via this response to Robertson, I aim to redress the tendency often seen in discussions around women, infertility, aging, and empowerment to unquestioningly accept what I argue are stereotypes and assumptions about women's views and capacity to reason. PMID:29868183

  19. Land Cover

    Data.gov (United States)

    Kansas Data Access and Support Center — The Land Cover database depicts 10 general land cover classes for the State of Kansas. The database was compiled from a digital classification of Landsat Thematic...

  20. Mulighedernes land?

    DEFF Research Database (Denmark)

    Munck Petersen, Rikke

    2001-01-01

    Kommentar om arbejde med det åbne land i forlængelse af konfencen "Mulighedernes land" og vigtigheden af at landskabsarkitekter går aktivt ind i debatten og arbejdet med landskabets forandring i Danmark.......Kommentar om arbejde med det åbne land i forlængelse af konfencen "Mulighedernes land" og vigtigheden af at landskabsarkitekter går aktivt ind i debatten og arbejdet med landskabets forandring i Danmark....

  1. Behavioral Modeling of WSN MAC Layer Security Attacks: A Sequential UML Approach

    DEFF Research Database (Denmark)

    Pawar, Pranav M.; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2012-01-01

    is the vulnerability to security attacks/threats. The performance and behavior of a WSN are vastly affected by such attacks. In order to be able to better address the vulnerabilities of WSNs in terms of security, it is important to understand the behavior of the attacks. This paper addresses the behavioral modeling...... of medium access control (MAC) security attacks in WSNs. The MAC layer is responsible for energy consumption, delay and channel utilization of the network and attacks on this layer can introduce significant degradation of the individual sensor nodes due to energy drain and in performance due to delays....... The behavioral modeling of attacks will be beneficial for designing efficient and secure MAC layer protocols. The security attacks are modeled using a sequential diagram approach of Unified Modeling Language (UML). Further, a new attack definition, specific to hybrid MAC mechanisms, is proposed....

  2. Experimental Evaluation of Simulation Abstractions for Wireless Sensor Network MAC Protocols

    Directory of Open Access Journals (Sweden)

    G. P. Halkes

    2010-01-01

    Full Text Available The evaluation of MAC protocols for Wireless Sensor Networks (WSNs is often performed through simulation. These simulations necessarily abstract away from reality in many ways. However, the impact of these abstractions on the results of the simulations has received only limited attention. Moreover, many studies on the accuracy of simulation have studied either the physical layer and per link effects or routing protocol effects. To the best of our knowledge, no other work has focused on the study of the simulation abstractions with respect to MAC protocol performance. In this paper, we present the results of an experimental study of two often used abstractions in the simulation of WSN MAC protocols. We show that a simple SNR-based reception model can provide quite accurate results for metrics commonly used to evaluate MAC protocols. Furthermore, we provide an analysis of what the main sources of deviation are and thereby how the simulations can be improved to provide even better results.

  3. A new architecture and MAC protocol for fully flexible hybrid WDM/TDM PON

    NARCIS (Netherlands)

    Das, G.; Lannoo, B.; Jung, H.D.; Koonen, A.M.J.; Colle, D.; Pickavet, M.; Demeester, P.

    2009-01-01

    In this paper we propose a novel architecture and MAC protocol for a scalable, cost effective WDM / TDM PON providing fully flexible dynamic bandwidth allocation for upstream and downstream data transmission.

  4. Evaluation of video transmission of MAC protocols in wireless sensor network

    Science.gov (United States)

    Maulidin, Mahmuddin, M.; Kamaruddin, L. M.; Elsaikh, Mohamed

    2016-08-01

    Wireless Sensor Network (WSN) is a wireless network which consists of sensor nodes scattered in a particular area which are used to monitor physical or environment condition. Each node in WSN is also scattered in sensor field, so an appropriate scheme of MAC protocol should have to develop communication link for data transferring. Video transmission is one of the important applications for the future that can be transmitted with low aspect in side of cost and also power consumption. In this paper, comparison of five different MAC WSN protocol for video transmission namely IEEE 802.11 standard, IEEE 802.15.4 standard, CSMA/CA, Berkeley-MAC, and Lightweight-MAC protocol are studied. Simulation experiment has been conducted in OMNeT++ with INET network simulator software to evaluate the performance. Obtained results indicate that IEEE 802.11 works better than other protocol in term of packet delivery, throughput, and latency.

  5. Corrections to "Connectivity-Based Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs"

    Directory of Open Access Journals (Sweden)

    Choi Woo-Yong

    2010-01-01

    Full Text Available We have found the errors in the throughput formulae presented in our paper "Connectivity-based reliable multicast MAC protocol for IEEE 802.11 wireless LANs". We provide the corrected formulae and numerical results.

  6. Analysis of an Adaptive P-Persistent MAC Scheme for WLAN Providing Delay Fairness

    Science.gov (United States)

    Yen, Chih-Ming; Chang, Chung-Ju; Chen, Yih-Shen; Huang, Ching Yao

    The paper proposes and analyzes an adaptive p-persistent-based (APP) medium access control (MAC) scheme for IEEE 802.11 WLAN. The APP MAC scheme intends to support delay fairness for every station in each access, denoting small delay variance. It differentiates permission probabilities of transmission for stations which are incurred with various packet delays. This permission probability is designed as a function of the numbers of retransmissions and re-backoffs so that stations with larger packet delay are endowed with higher permission probability. Also, the scheme is analyzed by a Markov-chain analysis, where the collision probability, the system throughput, and the average delay are successfully obtained. Numerical results show that the proposed APP MAC scheme can attain lower mean delay and higher mean throughput. In the mean time, simulation results are given to justify the validity of the analysis, and also show that the APP MAC scheme can achieve more delay fairness than conventional algorithms.

  7. 78 FR 26711 - Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Liquidity...

    Science.gov (United States)

    2013-05-08

    ... Funding and Fiscal Affairs; Farmer Mac Liquidity Management ACTION: Proposed rule; reopening of comment... proposed rule that would amend its liquidity management regulations for the Federal Agricultural Mortgage... comment on the proposed liquidity regulations. [[Page 26712

  8. A Critique of MacIntyrean Morality From a Kantian Perspective

    OpenAIRE

    Krishna Mani Pathak

    2014-01-01

    This article is a critical examination of MacIntyre’s notion of morality in reference to Kant’s deontological moral theory. The examination shows that MacIntyre (a) criticizes Kant’s moral theory to defend virtue ethics or neo-Aristotelian ethics with a weak notion of morality; (b) favors the idea of local morality, which does not leave any room for moral assessment and reciprocity in an intercultural domain; and (c) f...

  9. Strategy, Operational Art and MacArthur in the Southwest Pacific 1944

    Science.gov (United States)

    2016-05-26

    Guinea Campaign.11 It studies the campaign exclusively from the February 1944 through October 1944. The choice in dates argues that the campaign...the Pacific. King continued to maintain that MacArthur’s line of operation in SWPA, toward the Philippines to the exclusion of the central Pacific...with Nimitz allowed MacArthur the rare luxury of aircraft carriers providing a protective bubble over both the Morotai and Palaus operations. Escort

  10. Are Rural Costs of Living Lower? Evidence from a Big Mac Index Approach

    OpenAIRE

    Scott Loveridge; Dusan Paredes

    2015-01-01

    Rural leaders can point to low housing costs as a reason that their area should be competitive for business attraction. To what extent do rural housing costs offset transportation and other locational disadvantages in costs structures? The US lacks information to systematically answer the question. We adapt a strategy employed by The Economist in exploring purchasing power parity: the Big Mac Index. We gather information on Big Mac prices with a random sample of restaurants across the contigu...

  11. Profile of a leader. Alena Jean MacMaster: administrator, educator, professional activist and community advocate.

    Science.gov (United States)

    Gautreau, G; Winans, P

    1999-01-01

    This paper profiles Alena Jean MacMaster, an extraordinary nurse leader, activist, visionary and humanitarian from New Brunswick. Her determination and drive were instrumental in fostering the development and progression of health care, nursing education and nursing services at the local, provincial, federal and international levels. "First, loyalty to the institution in which you serve. The patient is the most important person in the entire institution," was Miss MacMaster's guiding principle throughout her career.

  12. MAC Version 3.3, MBA Version 1.3 acceptance test summary report

    International Nuclear Information System (INIS)

    Russell, V.K.

    1994-01-01

    The K Basins Materials Accounting (MAC) and Materials Balance (MBA) programs had the Paradox Code Cleanup ATP run to check out the systems. This report describes the results of the test and provides the signoff sheets associated with the testing. The Acceptance Test results indicate that the MAC and MBA systems are ready for operation using the cleaned up code. The final codes were removed to the production space on the customer server on April 15th

  13. A Full-Duplex MAC Tailored for 5G Wireless Networks

    Directory of Open Access Journals (Sweden)

    Lucas de Melo Guimarães

    2018-01-01

    Full Text Available The increasing demands for high-data rate traffic stimulated the development of the fifth-generation (5G mobile networks. The envisioned 5G network is expected to meet its challenge by devising means to further improve spectrum usage. Many alternatives to enhance spectrum usage are being researched, such as massive MIMO, operation in mmWave frequency, cognitive radio, and the employment of full-duplex antennas. Efficient utilization of the potential of any of these technologies faces a set of challenges related to medium access control (MAC schemes. This work focuses on MAC schemes tailored for full-duplex antennas, since they are expected to play a major role in the foreseeable 5G networks. In this context, this paper presents a MAC layer technique to improve total transmission time when full-duplex antennas are employed. Several evaluations in different scenarios are conducted to assess the proposed MAC scheme. Numerical results show that the proposed scheme provides gains up to 156% when compared to a state-of-the-art full-duplex antenna MAC protocol. Compared to traditional half-duplex antenna MAC protocols, the proposed scheme yields gain up to 412%.

  14. Functional Implications of an Intermeshing Cogwheel-like Interaction between TolC and MacA in the Action of Macrolide-specific Efflux Pump MacAB-TolC*

    Science.gov (United States)

    Xu, Yongbin; Song, Saemee; Moeller, Arne; Kim, Nahee; Piao, Shunfu; Sim, Se-Hoon; Kang, Mooseok; Yu, Wookyung; Cho, Hyun-Soo; Chang, Iksoo; Lee, Kangseok; Ha, Nam-Chul

    2011-01-01

    Macrolide-specific efflux pump MacAB-TolC has been identified in diverse Gram-negative bacteria including Escherichia coli. The inner membrane transporter MacB requires the outer membrane factor TolC and the periplasmic adaptor protein MacA to form a functional tripartite complex. In this study, we used a chimeric protein containing the tip region of the TolC α-barrel to investigate the role of the TolC α-barrel tip region with regard to its interaction with MacA. The chimeric protein formed a stable complex with MacA, and the complex formation was abolished by substitution at the functionally essential residues located at the MacA α-helical tip region. Electron microscopic study delineated that this complex was made by tip-to-tip interaction between the tip regions of the α-barrels of TolC and MacA, which correlated well with the TolC and MacA complex calculated by molecular dynamics. Taken together, our results demonstrate that the MacA hexamer interacts with TolC in a tip-to-tip manner, and implies the manner by which MacA induces opening of the TolC channel. PMID:21325274

  15. Functional implications of an intermeshing cogwheel-like interaction between TolC and MacA in the action of macrolide-specific efflux pump MacAB-TolC.

    Science.gov (United States)

    Xu, Yongbin; Song, Saemee; Moeller, Arne; Kim, Nahee; Piao, Shunfu; Sim, Se-Hoon; Kang, Mooseok; Yu, Wookyung; Cho, Hyun-Soo; Chang, Iksoo; Lee, Kangseok; Ha, Nam-Chul

    2011-04-15

    Macrolide-specific efflux pump MacAB-TolC has been identified in diverse gram-negative bacteria including Escherichia coli. The inner membrane transporter MacB requires the outer membrane factor TolC and the periplasmic adaptor protein MacA to form a functional tripartite complex. In this study, we used a chimeric protein containing the tip region of the TolC α-barrel to investigate the role of the TolC α-barrel tip region with regard to its interaction with MacA. The chimeric protein formed a stable complex with MacA, and the complex formation was abolished by substitution at the functionally essential residues located at the MacA α-helical tip region. Electron microscopic study delineated that this complex was made by tip-to-tip interaction between the tip regions of the α-barrels of TolC and MacA, which correlated well with the TolC and MacA complex calculated by molecular dynamics. Taken together, our results demonstrate that the MacA hexamer interacts with TolC in a tip-to-tip manner, and implies the manner by which MacA induces opening of the TolC channel.

  16. McMAC: Towards a MAC Protocol with Multi-Constrained QoS Provisioning for Diverse Traffic in Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Mostafa Monowar

    2012-11-01

    Full Text Available The emergence of heterogeneous applications with diverse requirements forresource-constrained Wireless Body Area Networks (WBANs poses significant challengesfor provisioning Quality of Service (QoS with multi-constraints (delay and reliability whilepreserving energy efficiency. To address such challenges, this paper proposes McMAC,a MAC protocol with multi-constrained QoS provisioning for diverse traffic classes inWBANs. McMAC classifies traffic based on their multi-constrained QoS demands andintroduces a novel superframe structure based on the "transmit-whenever-appropriate"principle, which allows diverse periods for diverse traffic classes according to their respectiveQoS requirements. Furthermore, a novel emergency packet handling mechanism is proposedto ensure packet delivery with the least possible delay and the highest reliability. McMACis also modeled analytically, and extensive simulations were performed to evaluate itsperformance. The results reveal that McMAC achieves the desired delay and reliabilityguarantee according to the requirements of a particular traffic class while achieving energyefficiency.

  17. MacDonald Dam reconstruction : using roller-compacted concrete

    Energy Technology Data Exchange (ETDEWEB)

    O' Neil, E. [AMEC Earth and Environmental Ltd., Sydney, NS (Canada)

    2007-04-01

    Located in Nova Scotia, the MacDonald Dam was commissioned in 1928. The dam consists of a 122 metre-long, 16 metre-high concrete structure comprised of an intake structure, stoplog openings, and a 34 metre-long free-overflow spillway. A 488 metre-long power canal was added as an upgrade in the 1950s. This paper provided details of the roller-compact concrete (RCC) used in the dam's recent rehabilitation following a dam failure analysis in 2003 by Nova Scotia Power Inc. RCC was chosen to help keep the dam's construction project on schedule. The layout and cross-section of the spillway was selected with consideration given to the RCC placing operation. A lift thickness of 0.20 m was selected. A formed ogee crest consisting of conventional reinforced concrete was constructed on top of the RCC. The downstream steps of the spillway were also covered with cast-in-place concrete. A low level sluice was designed to resist the weight of the wet RCC. The design compressive strength of the RCC was 20 MPa. The forms used to support the cast-in-place facing concrete on the upstream face of the dam were constructed full height and were braced back to the downstream face of the existing concrete structure prior to the start of RCC placement. Formwork inserts were placed in the facing concrete as construction progressed. Crack inducers were pre-placed on the forms. Aggregates from a local source were transported to a pug mill as the RCC construction progressed. The RCC was spread into 0.20 m lifts using a small bull-dozer, and the facing concrete was vibrated into the lift below. RCC lifts were compacted using a 9 tonne vibratory drum roller. The RCC placing operation was completed over a period of 10 days. Following the completion of the RCC portion of the dam, the remainder of the cast-in-place concrete was completed. It was concluded that the RCC provided a durable, low-maintenance structure that was completed at a lower price and in a shorter time-frame than

  18. MacDUST - a powder diffraction package developed for the ''ADONE'' high resolution diffraction station

    International Nuclear Information System (INIS)

    Burattini, E.; Cappuccio, G.; Maistrelli, P.; Simeoni, S.

    1993-01-01

    A High Resolution Powder Diffraction Station (PO.DI.STA.) was installed at the beginning of 1991 on the ADONE-Wiggler magnet beam line. The station and the first powder diffraction spectra, collected with synchrotron radiation, were presented at the EPDIC-1 Conference. More details can also be found in. For this station, a very sophisticated software package ''MacDUST'' has been developed on an Apple Macintosh computer, using the Microsoft QuickBASIC compiler. It allows very easy and comfortable operations by means of a graphical user interface environment, typical of the Macintosh system. The package consists of five major programs. The main program, MacDIFF, performs all the graphic operations on the experimental data, including zooming, overlapping, cursor scanning and editing of patterns, control of output operations to printers and HPGL plotters. It also includes several analysis routines for data smoothing, a first derivative peak search algorithm, two background subtraction routines and two profile fitting programs: one based on the simplex method and the other on the Marquardt modification of a least-square algorithm. MacPDF and MacRIC are both dedicated to phase identification. The first program is an archive manager for searching, displaying and printing phase records; MacRIC is a graphic aided search-match program based on the Hanawalt algorithm. Mac3-DIM is a plot program, useful, e.g., for representing kinetics three dimensionally. MacRIET is a Macintosh version of the well known Rietveld refinement program. This version, besides conventional structure refinements, also allows the determination of micro structural parameters, i.e. micro strain and crystallite size. The program can also be used to simulate a pattern, once the structure of the compound is known. Taking advantage of the very intuitive Macintosh graphic user interface, through dialog and alert boxes, the program allows straightforward introduction and modification of the structure

  19. An energy-efficient MAC protocol using dynamic queue management for delay-tolerant mobile sensor networks.

    Science.gov (United States)

    Li, Jie; Li, Qiyue; Qu, Yugui; Zhao, Baohua

    2011-01-01

    Conventional MAC protocols for wireless sensor network perform poorly when faced with a delay-tolerant mobile network environment. Characterized by a highly dynamic and sparse topology, poor network connectivity as well as data delay-tolerance, delay-tolerant mobile sensor networks exacerbate the severe power constraints and memory limitations of nodes. This paper proposes an energy-efficient MAC protocol using dynamic queue management (EQ-MAC) for power saving and data queue management. Via data transfers initiated by the target sink and the use of a dynamic queue management strategy based on priority, EQ-MAC effectively avoids untargeted transfers, increases the chance of successful data transmission, and makes useful data reach the target terminal in a timely manner. Experimental results show that EQ-MAC has high energy efficiency in comparison with a conventional MAC protocol. It also achieves a 46% decrease in packet drop probability, 79% increase in system throughput, and 25% decrease in mean packet delay.

  20. Outside-In Signal Transmission by Conformational Changes in Integrin Mac-11

    Science.gov (United States)

    Lefort, Craig T.; Hyun, Young-Min; Schultz, Joanne B.; Law, Foon-Yee; Waugh, Richard E.; Knauf, Philip A.; Kim, Minsoo

    2010-01-01

    Intracellular signals associated with or triggered by integrin ligation can control cell survival, differentiation, proliferation, and migration. Despite accumulating evidence that conformational changes regulate integrin affinity to its ligands, how integrin structure regulates signal transmission from the outside to the inside of the cell remains elusive. Using fluorescence resonance energy transfer, we addressed whether conformational changes in integrin Mac-1 are sufficient to transmit outside-in signals in human neutrophils. Mac-1 conformational activation induced by ligand occupancy or activating Ab binding, but not integrin clustering, triggered similar patterns of intracellular protein tyrosine phosphorylation, including Akt phosphorylation, and inhibited spontaneous neutrophil apoptosis, indicating that global conformational changes are critical for Mac-1-dependent outside-in signal transduction. In neutrophils and myeloid K562 cells, ligand ICAM-1 or activating Ab binding promoted switchblade-like extension of the Mac-1 extracellular domain and separation of the αM and β2 subunit cytoplasmic tails, two structural hallmarks of integrin activation. These data suggest the primacy of global conformational changes in the generation of Mac-1 outside-in signals. PMID:19864611

  1. Eliminating the Heart from the Curcumin Molecule: Monocarbonyl Curcumin Mimics (MACs)

    Science.gov (United States)

    Shetty, Dinesh; Kim, Yong Joon; Shim, Hyunsuk; Snyder, James P.

    2015-01-01

    Curcumin is a natural product with several thousand years of heritage. Its traditional Asian application to human ailments has been subjected in recent decades to worldwide pharmacological, biochemical and clinical investigations. Curcumin’s Achilles heel lies in its poor aqueous solubility and rapid degradation at pH ~ 7.4. Researchers have sought to unlock curcumin’s assets by chemical manipulation. One class of molecules under scrutiny are the monocarbonyl analogs of curcumin (MACs). A thousand plus such agents have been created and tested primarily against cancer and inflammation. The outcome is clear. In vitro, MACs furnish a 10–20 fold potency gain vs. curcumin for numerous cancer cell lines and cellular proteins. Similarly, MACs have successfully demonstrated better pharmacokinetic (PK) profiles in mice and greater tumor regression in cancer xenografts in vivo than curcumin. The compounds reveal limited toxicity as measured by murine weight gain and histopathological assessment. To our knowledge, MAC members have not yet been monitored in larger animals or humans. However, Phase 1 clinical trials are certainly on the horizon. The present review focuses on the large and evolving body of work in cancer and inflammation, but also covers MAC structural diversity and early discovery for treatment of bacteria, tuberculosis, Alzheimer’s disease and malaria. PMID:25547726

  2. Crystallization and preliminary X-ray crystallographic analysis of MacA from Actinobacillus actinomycetemcomitans

    International Nuclear Information System (INIS)

    Piao, Shunfu; Xu, Yongbin; Ha, Nam-Chul

    2008-01-01

    A periplasmic membrane-fusion protein MacA from Actinobacillus actinomycetemcomitans, an essential component of the multidrug efflux pump in Gram-negative bacteria, was crystallized. Periplasmic membrane-fusion proteins (MFPs) are an essential component of the multidrug efflux pump in Gram-negative bacteria. They play a crucial role in bridging the outer membrane porin TolC and two distinct types of inner membrane transporters. The MFP MacA bridges the inner membrane ABC-type multidrug transporter MacB and the outer membrane porin TolC. MacA from the pathogenic bacterium Actinobacillus actinomycetemcomitans was expressed in Escherichia coli B834 (DE3) and the recombinant protein was purified using Ni–NTA affinity, Q anion-exchange and gel-filtration chromatography. The purified MacA protein was crystallized using the vapour-diffusion method. A MAD diffraction data set was collected to a resolution of 3.0 Å at 100 K. The crystal belongs to space group P622, with unit-cell parameters a = b = 109.2, c = 255.4 Å, α = β = 90, γ = 120°, and contains one molecule in the asymmetric unit

  3. A Power-Optimized Cooperative MAC Protocol for Lifetime Extension in Wireless Sensor Networks.

    Science.gov (United States)

    Liu, Kai; Wu, Shan; Huang, Bo; Liu, Feng; Xu, Zhen

    2016-10-01

    In wireless sensor networks, in order to satisfy the requirement of long working time of energy-limited nodes, we need to design an energy-efficient and lifetime-extended medium access control (MAC) protocol. In this paper, a node cooperation mechanism that one or multiple nodes with higher channel gain and sufficient residual energy help a sender relay its data packets to its recipient is employed to achieve this objective. We first propose a transmission power optimization algorithm to prolong network lifetime by optimizing the transmission powers of the sender and its cooperative nodes to maximize their minimum residual energy after their data packet transmissions. Based on it, we propose a corresponding power-optimized cooperative MAC protocol. A cooperative node contention mechanism is designed to ensure that the sender can effectively select a group of cooperative nodes with the lowest energy consumption and the best channel quality for cooperative transmissions, thus further improving the energy efficiency. Simulation results show that compared to typical MAC protocol with direct transmissions and energy-efficient cooperative MAC protocol, the proposed cooperative MAC protocol can efficiently improve the energy efficiency and extend the network lifetime.

  4. Efficient MAC Protocol for Hybrid Wireless Network with Heterogeneous Sensor Nodes

    Directory of Open Access Journals (Sweden)

    Md. Nasre Alam

    2016-01-01

    Full Text Available Although several Directional Medium Access Control (DMAC protocols have been designed for use with homogeneous networks, it can take a substantial amount of time to change sensor nodes that are equipped with an omnidirectional antenna for sensor nodes with a directional antenna. Thus, we require a novel MAC protocol for use with an intermediate wireless network that consists of heterogeneous sensor nodes equipped with either an omnidirectional antenna or a directional antenna. The MAC protocols that have been designed for use in homogeneous networks are not suitable for use in a hybrid network due to deaf, hidden, and exposed nodes. Therefore, we propose a MAC protocol that exploits the characteristics of a directional antenna and can also work efficiently with omnidirectional nodes in a hybrid network. In order to address the deaf, hidden, and exposed node problems, we define RTS/CTS for the neighbor (RTSN/CTSN and Neighbor Information (NIP packets. The performance of the proposed MAC protocol is evaluated through a numerical analysis using a Markov model. In addition, the analytical results of the MAC protocol are verified through an OPNET simulation.

  5. Eliminating the Heart from the Curcumin Molecule: Monocarbonyl Curcumin Mimics (MACs

    Directory of Open Access Journals (Sweden)

    Dinesh Shetty

    2014-12-01

    Full Text Available Curcumin is a natural product with several thousand years of heritage. Its traditional Asian application to human ailments has been subjected in recent decades to worldwide pharmacological, biochemical and clinical investigations. Curcumin’s Achilles heel lies in its poor aqueous solubility and rapid degradation at pH ~ 7.4. Researchers have sought to unlock curcumin’s assets by chemical manipulation. One class of molecules under scrutiny are the monocarbonyl analogs of curcumin (MACs. A thousand plus such agents have been created and tested primarily against cancer and inflammation. The outcome is clear. In vitro, MACs furnish a 10–20 fold potency gain vs. curcumin for numerous cancer cell lines and cellular proteins. Similarly, MACs have successfully demonstrated better pharmacokinetic (PK profiles in mice and greater tumor regression in cancer xenografts in vivo than curcumin. The compounds reveal limited toxicity as measured by murine weight gain and histopathological assessment. To our knowledge, MAC members have not yet been monitored in larger animals or humans. However, Phase 1 clinical trials are certainly on the horizon. The present review focuses on the large and evolving body of work in cancer and inflammation, but also covers MAC structural diversity and early discovery for treatment of bacteria, tuberculosis, Alzheimer’s disease and malaria.

  6. Crystallization and preliminary X-ray crystallographic analysis of MacA from Actinobacillus actinomycetemcomitans

    Energy Technology Data Exchange (ETDEWEB)

    Piao, Shunfu; Xu, Yongbin; Ha, Nam-Chul, E-mail: hnc@pusan.ac.kr [College of Pharmacy and Research Institute for Drug Development, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of)

    2008-05-01

    A periplasmic membrane-fusion protein MacA from Actinobacillus actinomycetemcomitans, an essential component of the multidrug efflux pump in Gram-negative bacteria, was crystallized. Periplasmic membrane-fusion proteins (MFPs) are an essential component of the multidrug efflux pump in Gram-negative bacteria. They play a crucial role in bridging the outer membrane porin TolC and two distinct types of inner membrane transporters. The MFP MacA bridges the inner membrane ABC-type multidrug transporter MacB and the outer membrane porin TolC. MacA from the pathogenic bacterium Actinobacillus actinomycetemcomitans was expressed in Escherichia coli B834 (DE3) and the recombinant protein was purified using Ni–NTA affinity, Q anion-exchange and gel-filtration chromatography. The purified MacA protein was crystallized using the vapour-diffusion method. A MAD diffraction data set was collected to a resolution of 3.0 Å at 100 K. The crystal belongs to space group P622, with unit-cell parameters a = b = 109.2, c = 255.4 Å, α = β = 90, γ = 120°, and contains one molecule in the asymmetric unit.

  7. MAP, MAC, and vortex-rings configurations in the Weinberg-Salam model

    Science.gov (United States)

    Teh, Rosy; Ng, Ban-Loong; Wong, Khai-Ming

    2015-11-01

    We report on the presence of new axially symmetric monopoles, antimonopoles and vortex-rings solutions of the SU(2)×U(1) Weinberg-Salam model of electromagnetic and weak interactions. When the ϕ-winding number n = 1, and 2, the configurations are monopole-antimonopole pair (MAP) and monopole-antimonopole chain (MAC) with poles of alternating sign magnetic charge arranged along the z-axis. Vortex-rings start to appear from the MAP and MAC configurations when the winding number n = 3. The MAP configurations possess zero net magnetic charge whereas the MAC configurations possess net magnetic charge of 4 πn / e. In the MAP configurations, the monopole-antimonopole pair is bounded by the Z0 field flux string and there is an electromagnetic current loop encircling it. The monopole and antimonopole possess magnetic charges ± 4πn/e sin2θW respectively. In the MAC configurations there is no string connecting the monopole and the adjacent antimonopole and they possess magnetic charges ± 4 πn/e respectively. The MAC configurations possess infinite total energy and zero magnetic dipole moment whereas the MAP configurations which are actually sphalerons possess finite total energy and magnetic dipole moment. The configurations were investigated for varying values of Higgs self-coupling constant 0 ≤ λ ≤ 40 at Weinberg angle θW = π/4.

  8. Detection of constitutive heterodimerization of the integrin Mac-1 subunits by fluorescence resonance energy transfer in living cells

    International Nuclear Information System (INIS)

    Fu Guo; Yang Huayan; Wang Chen; Zhang Feng; You Zhendong; Wang Guiying; He Cheng; Chen Yizhang; Xu Zhihan

    2006-01-01

    Macrophage differentiation antigen associated with complement three receptor function (Mac-1) belongs to β 2 subfamily of integrins that mediate important cell-cell and cell-extracellular matrix interactions. Biochemical studies have indicated that Mac-1 is a constitutive heterodimer in vitro. Here, we detected the heterodimerization of Mac-1 subunits in living cells by means of two fluorescence resonance energy transfer (FRET) techniques (fluorescence microscopy and fluorescence spectroscopy) and our results demonstrated that there is constitutive heterodimerization of the Mac-1 subunits and this constitutive heterodimerization of the Mac-1 subunits is cell-type independent. Through FRET imaging, we found that heterodimers of Mac-1 mainly localized in plasma membrane, perinuclear, and Golgi area in living cells. Furthermore, through analysis of the estimated physical distances between cyan fluorescent protein (CFP) and yellow fluorescent protein (YFP) fused to Mac-1 subunits, we suggested that the conformation of Mac-1 subunits is not affected by the fusion of CFP or YFP and inferred that Mac-1 subunits take different conformation when expressed in Chinese hamster ovary (CHO) and human embryonic kidney (HEK) 293T cells, respectively

  9. Cosmology of a Friedmann-Lamaître-Robertson-Walker 3-brane, late-time cosmic acceleration, and the cosmic coincidence.

    Science.gov (United States)

    Doolin, Ciaran; Neupane, Ishwaree P

    2013-04-05

    A late epoch cosmic acceleration may be naturally entangled with cosmic coincidence--the observation that at the onset of acceleration the vacuum energy density fraction nearly coincides with the matter density fraction. In this Letter we show that this is indeed the case with the cosmology of a Friedmann-Lamaître-Robertson-Walker (FLRW) 3-brane in a five-dimensional anti-de Sitter spacetime. We derive the four-dimensional effective action on a FLRW 3-brane, from which we obtain a mass-reduction formula, namely, M(P)(2) = ρ(b)/|Λ(5)|, where M(P) is the effective (normalized) Planck mass, Λ(5) is the five-dimensional cosmological constant, and ρ(b) is the sum of the 3-brane tension V and the matter density ρ. Although the range of variation in ρ(b) is strongly constrained, the big bang nucleosynthesis bound on the time variation of the effective Newton constant G(N) = (8πM(P)(2))(-1) is satisfied when the ratio V/ρ ≳ O(10(2)) on cosmological scales. The same bound leads to an effective equation of state close to -1 at late epochs in accordance with astrophysical and cosmological observations.

  10. MAC-layer protocol for TCP fairness in Wireless Mesh Networks

    KAUST Repository

    Nawab, Faisal

    2012-08-01

    In this paper we study the interactions of TCP and IEEE 802.11 MAC in Wireless Mesh Networks (WMNs). We use a Markov chain to capture the behavior of TCP sessions, particularly the impact on network throughput performance due to the effect of queue utilization and packet relaying. A closed form solution is derived to numerically determine the throughput. Based on the developed model, we propose a distributed MAC protocol to alleviate the unfairness problem in WMNs. Our protocol uses the age of packet as a priority metric for packet scheduling. Simulation is conducted to validate our model and to illustrate the fairness characteristics of our proposed MAC protocol. We conclude that we can achieve fairness with only little impact on network capacity.

  11. Microcrystallography, high-pressure cryocooling and BioSAXS at MacCHESS

    Energy Technology Data Exchange (ETDEWEB)

    Englich, Ulrich, E-mail: ue22@cornell.edu; Kriksunov, Irina A. [MacCHESS (Macromolecular Diffraction Facility at CHESS), Cornell University, Ithaca, NY 14853 (United States); Cerione, Richard A. [MacCHESS (Macromolecular Diffraction Facility at CHESS), Cornell University, Ithaca, NY 14853 (United States); Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853 (United States); Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853 (United States); Cook, Michael J.; Gillilan, Richard [MacCHESS (Macromolecular Diffraction Facility at CHESS), Cornell University, Ithaca, NY 14853 (United States); Gruner, Sol M. [Field of Biophysics, Cornell University, Ithaca, NY 14853 (United States); Physics Department, Cornell University, Ithaca, NY 14853 (United States); Huang, Qingqui; Kim, Chae Un; Miller, William; Nielsen, Soren; Schuller, David; Smith, Scott; Szebenyi, Doletha M. E. [MacCHESS (Macromolecular Diffraction Facility at CHESS), Cornell University, Ithaca, NY 14853 (United States)

    2011-01-01

    Three research initiatives pursued by the Macromolecular Diffraction Facility at the Cornell High Energy Synchrotron Source (MacCHESS) are presented. The Macromolecular Diffraction Facility at the Cornell High Energy Synchrotron Source (MacCHESS) is a national research resource supported by the National Center for Research Resources of the US National Institutes of Health. MacCHESS is pursuing several research initiatives designed to benefit both CHESS users and the wider structural biology community. Three initiatives are presented in further detail: microcrystallography, which aims to improve the collection of diffraction data from crystals a few micrometers across, or small well diffracting regions of inhomogeneous crystals, so as to obtain high-resolution structures; pressure cryocooling, which can stabilize transient structures and reduce lattice damage during the cooling process; and BioSAXS (small-angle X-ray scattering on biological solutions), which can extract molecular shape and other structural information from macromolecules in solution.

  12. Learn Objective-C on the Mac for OS X and iOS

    CERN Document Server

    Knaster, Scott; Malik, Waqar

    2012-01-01

    Learn to write apps for some of today's hottest technologies, including the iPhone and iPad (using iOS), as well as the Mac (using OS X). It starts with Objective-C, the base language on which the native iOS software development kit (SDK) and the OS X are based. Learn Objective-C on the Mac: For OS X and iOS, Second Edition updates a best selling book and is an extensive, newly updated guide to Objective-C. Objective-C is a powerful, object-oriented extension of C, making this update the perfect follow-up to Dave Mark's bestselling Learn C on the Mac. Whether you're an experienced C programmer

  13. Side channel analysis of some hash based MACs:A response to SHA-3 requirements

    DEFF Research Database (Denmark)

    The forthcoming NIST's Advanced Hash Standard (AHS) competition to select SHA-3 hash function requires that each candidate hash function submission must have at least one construction to support FIPS 198 HMAC application. As part of its evaluation, NIST is aiming to select either a candidate hash...... function which is more resistant to known side channel attacks (SCA) when plugged into HMAC, or that has an alternative MAC mode which is more resistant to known SCA than the other submitted alternatives. In response to this, we perform differential power analysis (DPA) on the possible smart card...... implementations of some of the recently proposed MAC alternatives to NMAC (a fully analyzed variant of HMAC) and HMAC algorithms and NMAC/HMAC versions of some recently proposed hash and compression function modes. We show that the recently proposed BNMAC and KMDP MAC schemes are even weaker than NMAC...

  14. Macular telangiectasia type 2 (MacTel) in a 34-year-old patient.

    Science.gov (United States)

    Nicolai, Heleen; Wirix, Mieke; Spielberg, Leigh; Leys, Anita

    2014-09-23

    We report macular telangiectasia type 2 (MacTel) in a 34-year-old man, the youngest patient so far published with MacTel type 2. The patient presented with metamorphopsia and impaired reading ability. Diagnosis was based on bilateral abnormal macular autofluorescence, perifoveal telangiectasia with fluorescein angiographic hyperfluorescence without cystoid oedema, a small foveal avascular zone, asymmetric configuration of the foveal pit, disruptions in the inner segment/outer segment layer and hyper-reflective haze and spots in the outer nuclear layer. Although MacTel usually manifests with a slowly progressive decrease in visual acuity in the fifth to seventh decades of life, younger patients may occasionally be diagnosed with the disease. Awareness of subtle signs of the condition is essential for early diagnosis. 2014 BMJ Publishing Group Ltd.

  15. A network architecture for precision formation flying using the IEEE 802.11 MAC Protocol

    Science.gov (United States)

    Clare, Loren P.; Gao, Jay L.; Jennings, Esther H.; Okino, Clayton

    2005-01-01

    Precision Formation Flying missions involve the tracking and maintenance of spacecraft in a desired geometric formation. The strong coupling of spacecraft in formation flying control requires inter-spacecraft communication to exchange information. In this paper, we present a network architecture that supports PFF control, from the initial random deployment phase to the final formation. We show that a suitable MAC layer for the application protocol is IEEE's 802.11 MAC protocol. IEEE 802.11 MAC has two modes of operations: DCF and PCF. We show that DCF is suitable for the initial deployment phase while switching to PCF when the spacecraft are in formation improves jitter and throughput. We also consider the effect of routing on protocol performance and suggest when it is profitable to turn off route discovery to achieve better network performance.

  16. LFA-1 and Mac-1 integrins bind to the serine/threonine-rich domain of thrombomodulin

    Energy Technology Data Exchange (ETDEWEB)

    Kawamoto, Eiji [Department of Molecular Pathobiology and Cell Adhesion Biology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507 (Japan); Emergency and Critical Care Center, Mie University Hospital, 2-174 Edobashi, Tsu 514-8507 (Japan); Okamoto, Takayuki, E-mail: okamotot@doc.medic.mie-u.ac.jp [Department of Molecular Pathobiology and Cell Adhesion Biology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507 (Japan); Takagi, Yoshimi [Department of Molecular Pathobiology and Cell Adhesion Biology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507 (Japan); Honda, Goichi [Medical Affairs Department, Asahi Kasei Pharma Corporation, 1-105 Kanda Jinbo-cho, Chiyoda-ku, Tokyo 101-8101 (Japan); Suzuki, Koji [Faculty of Pharmaceutical Science, Suzuka University of Medical Science, 3500-3, Minamitamagaki-cho, Suzuka, Mie 513-8679 (Japan); Imai, Hiroshi [Emergency and Critical Care Center, Mie University Hospital, 2-174 Edobashi, Tsu 514-8507 (Japan); Shimaoka, Motomu, E-mail: shimaoka@doc.medic.mie-u.ac.jp [Department of Molecular Pathobiology and Cell Adhesion Biology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507 (Japan)

    2016-05-13

    LFA-1 (αLβ2) and Mac-1 (αMβ2) integrins regulate leukocyte trafficking in health and disease by binding primarily to IgSF ligand ICAM-1 and ICAM-2 on endothelial cells. Here we have shown that the anti-coagulant molecule thrombomodulin (TM), found on the surface of endothelial cells, functions as a potentially new ligand for leukocyte integrins. We generated a recombinant extracellular domain of human TM and Fc fusion protein (TM-domains 123-Fc), and showed that pheripheral blood mononuclear cells (PBMCs) bind to TM-domains 123-Fc dependent upon integrin activation. We then demonstrated that αL integrin-blocking mAb, αM integrin-blocking mAb, and β2 integrin-blocking mAb inhibited the binding of PBMCs to TM-domains 123-Fc. Furthermore, we show that the serine/threonine-rich domain (domain 3) of TM is required for the interaction with the LFA-1 (αLβ2) and Mac-1 (αMβ2) integrins to occur on PBMCs. These results demonstrate that the LFA-1 and Mac-1 integrins on leukocytes bind to TM, thereby establishing the molecular and structural basis underlying LFA-1 and Mac-1 integrin interaction with TM on endothelial cells. In fact, integrin-TM interactions might be involved in the dynamic regulation of leukocyte adhesion with endothelial cells. - Highlights: • LFA-1 and Mac-1 integrins bind to the anti-coagulant molecule thrombomodulin. • The serine/threonine-rich domain of thrombomodulin is essential to interact with the LFA-1 and Mac-1 integrins on PBMCs. • Integrin-TM interactions might be involved in the dynamic regulation of leukocyte adhesion with endothelial cells.

  17. Conformational stability analyses of alpha subunit I domain of LFA-1 and Mac-1.

    Directory of Open Access Journals (Sweden)

    Debin Mao

    Full Text Available β₂ integrin of lymphocyte function-associated antigen-1 (LFA-1 or macrophage-1 antigen (Mac-1 binds to their common ligand of intercellular adhesion molecule-1 (ICAM-1 and mediates leukocyte-endothelial cell (EC adhesions in inflammation cascade. Although the two integrins are known to have distinct functions, the corresponding micro-structural bases remain unclear. Here (steered-molecular dynamics simulations were employed to elucidate the conformational stability of α subunit I domains of LFA-1 and Mac-1 in different affinity states and relevant I domain-ICAM-1 interaction features. Compared with low affinity (LA Mac-1, the LA LFA-1 I domain was unstable in the presence or absence of ICAM-1 ligand, stemming from diverse orientations of its α₇-helix with different motifs of zipper-like hydrophobic junction between α₁- and α₇-helices. Meanwhile, spontaneous transition of LFA-1 I domain from LA state to intermediate affinity (IA state was first visualized. All the LA, IA, and high affinity (HA states of LFA-1 I domain and HA Mac-1 I domain were able to bind to ICAM-1 ligand effectively, while LA Mac-1 I domain was unfavorable for binding ligand presumably due to the specific orientation of S144 side-chain that capped the MIDAS ion. These results furthered our understanding in correlating the structural bases with their functions of LFA-1 and Mac-1 integrins from the viewpoint of I domain conformational stability and of the characteristics of I domain-ICAM-1 interactions.

  18. High-contrast MacNeille-PBS-based LCOS projection systems

    Science.gov (United States)

    Chen, Jianmin; Robinson, Michael G.; Sharp, Gary D.

    2005-04-01

    Contrast limits are investigated for MacNeille PBS based LCOS projection systems that use retarder stack filters (RSF). The two contributing factors are considered separately; namely the color management system and the panel port. To enhance performance of the former, skew ray compensated RSFs are introduced. For the latter, a general methodology is presented to optimize contrast by compensating the LCOS panel. It is shown that the orientation of the LCOS panel and compensator, relative to the MacNeille PBS, is critical. The significant impact of AR coating performance on system contrast is also revealed. A high contrast architecture will be presented by way of example.

  19. The MacNew Heart Disease health-related quality of life instrument: A summary

    Directory of Open Access Journals (Sweden)

    Guyatt Gordon

    2004-01-01

    Full Text Available Abstract Background The measurement of health, the effects of disease, and the impact of health care include not only an indication of changes in disease frequency and severity but also an estimate of patients' perception of health status before and after treatment. One of the more important developments in health care in the past decade may be the recognition that the patient's perspective is as legitimate and valid as the clinician's in monitoring health care outcomes. This has lead to the development of instruments to quantify the patients' perception of their health status before and after treatment. Methods We review evidence supporting the measurement properties of the MacNew Heart Disease Health-related Quality of Life [MacNew] Questionnaire which was designed to evaluate how daily activities and physical, emotional, and social functioning are affected by coronary heart disease and its treatment. Results Reliability was demonstrated by using internal consistency and the intraclass correlation coefficients for the three domains in the Dutch, English, Farsi, German, and Spanish versions of the MacNew. With internal consistency and intraclass correlation coefficients =>0.73, reliability is high. Validity of the MacNew was examined with factor analysis and three core underlying factors, physical, emotional, and social, were identified, explaining 63.0 – 66.5% of the observed variance and replicated in the translations with psychometric data. Construct validity of the MacNew was further demonstrated by extensive substantiation of the logical relationships, defined a priori, between items and other comparison tools. The MacNew is responsive and sensitive to changes in HRQL following various interventions for patients with heart disease with 11 of 13 effect size statistics >0.80. Taking an average of 10 minutes or less to complete, the respondent-burden for the MacNew is low and its acceptability is demonstrated by response rates of over 90

  20. A DUAL RESERVATION CDMA-BASED MAC PROTOCOL WITH POWER CONTROL FOR AD HOC NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Jia Min; Chen Huimin; Yuan Yuhua

    2007-01-01

    This paper proposes a new multi-channel Medium Access Control (MAC) protocol named as Dual Reservation Code Division Multiple Access (CDMA) based MAC protocol with Power Control (DRCPC). The code channel is divided into common channel, broadcast channel and several data channels. And dynamic power control mechanism is implemented to reduce near-far interference. Compared with IEEE 802.11 Distributed Coordination Function (DCF) protocol, the results show that the proposed mechanism improves the average throughput and limits the transmission delay efficiently.

  1. Learn Xcode Tools for Mac OS X and iPhone Development

    CERN Document Server

    Piper, I

    2010-01-01

    This book will give you a thorough grounding in the principal and supporting tools and technologies that make up the Xcode Developer Tools suite. Apple has provided a comprehensive collection of developer tools, and this is the first book to examine the complete Apple programming environment for both Mac OS X and iPhone. * Comprehensive coverage of all the Xcode developer tools * Additional coverage of useful third-party development tools* Not just a survey of features, but a serious examination of the complete development process for Mac OS X and iPhone applications What you'll learn* The boo

  2. Burgernomics: a big MacT guide to purchasing power parity

    OpenAIRE

    Michael R. Pakko; Patricia S. Pollard

    2003-01-01

    The theory of purchasing power parity (PPP) has long been a staple of international economic analysis. Recent years have seen the rise in popularity of a tongue-in-cheek, fast-food version of PPP: The Big Mac™ index. In this article, Michael Pakko and Patricia Pollard describe how comparisons of Big Mac prices around the world contain the ingredients necessary to demonstrate the fundamental principles of PPP. They show that the Big Mac index does nearly as well as more comprehensive measures ...

  3. Using The Economist’s Big Mac Index for Instruction

    OpenAIRE

    Stegelin, Forrest E.

    2012-01-01

    The Economist first launched the concept of the Big Mac Index in 1986 as a guide to whether currencies were at their correct exchange rate; it is not intended to be a precise predictor of currency movements around the globe, but simply a way to make exchange-rate theory and discussions a bit more digestible. First used as a humorous illustration, the term “burgernomics†was coined and the Big Mac index became an annual occurrence. It is based upon one of the oldest concepts in internationa...

  4. Survey is based on Synchronized and Asynchronized Approach of MAC Protocols in WSN

    Directory of Open Access Journals (Sweden)

    Soni Chaurasia

    2010-07-01

    Full Text Available A wireless network is made of spatially distributed autonomous devices. These devices are called sensors. The sensor is used for monitoring physical or environmental conditions. The potential application of wireless sensor network is environmental monitoring, healthcare applications and tactical systems. In this paper focus is on the MAC protocol for WSN. Wireless sensor network is deployed for wide range to send and receive data with the help of medium. Here literature survey of MAC protocol based on the synchronized and asynchronized approach is described which is used to meet different objective like access a medium, statistical channel allocation, spectrum utilization

  5. CoCoMac 2.0 and the future of tract-tracing databases

    OpenAIRE

    Rembrandt eBakker; Rembrandt eBakker; Rembrandt eBakker; Thomas eWachtler; Markus eDiesmann; Markus eDiesmann; Markus eDiesmann

    2012-01-01

    The CoCoMac database contains the results of published axonal tract-tracing studies in the macaque brain. The combined data are used to construct the macaque macro-connectome. We discuss the redevelopment of CoCoMac and compare it to six connectome-related projects: two resources that provide online access to raw tracing data in rodents, a connectome viewer for advanced 3d graphics, a partial but highly detailed rat connectome, a brain data management system that generates custom connectivity...

  6. The Mac'OS X command line Unix under the hood

    CERN Document Server

    McElhearn, Kirk

    2006-01-01

    The Mac command line offers a faster, easier way to accomplish many tasks. It''s also the medium for many commands that aren''t accessible using the GUI. The Mac OS X Command Line is a clear, concise, tutorial-style introduction to all the major functionality provided by the command line. It''s also packed with information the experienced users need, including little-known shortcuts and several chapters devoted to advanced topics. This is a book to get you started, but also a book you won't soon outgrow.

  7. A Critique of MacIntyrean Morality From a Kantian Perspective

    Directory of Open Access Journals (Sweden)

    Krishna Mani Pathak

    2014-04-01

    Full Text Available This article is a critical examination of MacIntyre’s notion of morality in reference to Kant’s deontological moral theory. The examination shows that MacIntyre (a criticizes Kant’s moral theory to defend virtue ethics or neo-Aristotelian ethics with a weak notion of morality; (b favors the idea of local morality, which does not leave any room for moral assessment and reciprocity in an intercultural domain; and (c fails to provide good arguments for his moral historicism and against Kant’s moral universalism.

  8. Federal Lands

    Data.gov (United States)

    Department of Homeland Security — This map layer consists of federally owned or administered lands of theUnited States, Puerto Rico, and the U.S. Virgin Islands. Only areas of 640 acres or more are...

  9. Land Research

    Science.gov (United States)

    EPA is working to develop methods and guidance to manage and clean up contaminated land, groundwater and nutrient pollution as well as develop innovative approaches to managing materials and waste including energy recovery.

  10. A hybrid path-oriented code assignment CDMA-based MAC protocol for underwater acoustic sensor networks.

    Science.gov (United States)

    Chen, Huifang; Fan, Guangyu; Xie, Lei; Cui, Jun-Hong

    2013-11-04

    Due to the characteristics of underwater acoustic channel, media access control (MAC) protocols designed for underwater acoustic sensor networks (UWASNs) are quite different from those for terrestrial wireless sensor networks. Moreover, in a sink-oriented network with event information generation in a sensor field and message forwarding to the sink hop-by-hop, the sensors near the sink have to transmit more packets than those far from the sink, and then a funneling effect occurs, which leads to packet congestion, collisions and losses, especially in UWASNs with long propagation delays. An improved CDMA-based MAC protocol, named path-oriented code assignment (POCA) CDMA MAC (POCA-CDMA-MAC), is proposed for UWASNs in this paper. In the proposed MAC protocol, both the round-robin method and CDMA technology are adopted to make the sink receive packets from multiple paths simultaneously. Since the number of paths for information gathering is much less than that of nodes, the length of the spreading code used in the POCA-CDMA-MAC protocol is shorter greatly than that used in the CDMA-based protocols with transmitter-oriented code assignment (TOCA) or receiver-oriented code assignment (ROCA). Simulation results show that the proposed POCA-CDMA-MAC protocol achieves a higher network throughput and a lower end-to-end delay compared to other CDMA-based MAC protocols.

  11. A Hybrid Path-Oriented Code Assignment CDMA-Based MAC Protocol for Underwater Acoustic Sensor Networks

    Directory of Open Access Journals (Sweden)

    Huifang Chen

    2013-11-01

    Full Text Available Due to the characteristics of underwater acoustic channel, media access control (MAC protocols designed for underwater acoustic sensor networks (UWASNs are quite different from those for terrestrial wireless sensor networks. Moreover, in a sink-oriented network with event information generation in a sensor field and message forwarding to the sink hop-by-hop, the sensors near the sink have to transmit more packets than those far from the sink, and then a funneling effect occurs, which leads to packet congestion, collisions and losses, especially in UWASNs with long propagation delays. An improved CDMA-based MAC protocol, named path-oriented code assignment (POCA CDMA MAC (POCA-CDMA-MAC, is proposed for UWASNs in this paper. In the proposed MAC protocol, both the round-robin method and CDMA technology are adopted to make the sink receive packets from multiple paths simultaneously. Since the number of paths for information gathering is much less than that of nodes, the length of the spreading code used in the POCA-CDMA-MAC protocol is shorter greatly than that used in the CDMA-based protocols with transmitter-oriented code assignment (TOCA or receiver-oriented code assignment (ROCA. Simulation results show that the proposed POCA-CDMA-MAC protocol achieves a higher network throughput and a lower end-to-end delay compared to other CDMA-based MAC protocols.

  12. Education for Personal Life: John MacMurray on Why Learning to Be Human Requires Emotional Discipline

    Science.gov (United States)

    MacAllister, James

    2014-01-01

    In this article I discuss the philosophy of John MacMurray, and in particular, his little-examined writings on discipline and emotion education. It is argued that discipline is a vital element in the emotion education MacMurray thought central to learning to be human, because for him it takes concerted effort to overcome the human tendency toward…

  13. Medicinal, Aromatic and Cosmetic (MAC) plants for community health and bio-cultural diversity conservation in Bali, Indonesia

    NARCIS (Netherlands)

    Leurs, Liesbeth Nathalie

    2010-01-01

    The general aim of this ethno-botanical study is to document, describe and analyse the Balinese community members’ knowledge, belief and practices with regard to medicinal, aromatic and cosmetic (MAC) plants in relation to community health and bio-cultural diversity conservation of MAC plants. This

  14. An Application of MacLaury's Vantage Theory to Abstract Categories: Identity and the Process of Categorisation

    Science.gov (United States)

    Fabiszak, Malgorzata

    2010-01-01

    This paper is an application of Robert E. MacLaury's Vantage Theory (VT) to the analysis of real life spoken discourse. It utilizes Dennis R. Preston's (1994) modification of MacLaury's VT. It elucidates how cognitive processes of coordinate selection and combination contribute to the on-line construction of category membership in the abstract…

  15. Mobile Device Management horizons for CERN Managed iOS and Mac Self-Service

    CERN Multimedia

    CERN. Geneva; MUSZKOWSKI, Maciek; BIPPUS, Vincent Nicolas

    2015-01-01

    Overview of the MDM (Mobile Device Mamagement) market in the context of the CERN needs and a discussion of technical capabilities of a range of MDM products, followed by a presentation of two new functionalities implemented using an MDM: Self-service Kiosk for Mac and delegated-management solution for professional tablets.

  16. A Survey of MAC Protocols for Cognitive Radio Body Area Networks.

    Science.gov (United States)

    Bhandari, Sabin; Moh, Sangman

    2015-04-20

    The advancement in electronics, wireless communications and integrated circuits has enabled the development of small low-power sensors and actuators that can be placed on, in or around the human body. A wireless body area network (WBAN) can be effectively used to deliver the sensory data to a central server, where it can be monitored, stored and analyzed. For more than a decade, cognitive radio (CR) technology has been widely adopted in wireless networks, as it utilizes the available spectra of licensed, as well as unlicensed bands. A cognitive radio body area network (CRBAN) is a CR-enabled WBAN. Unlike other wireless networks, CRBANs have specific requirements, such as being able to automatically sense their environments and to utilize unused, licensed spectra without interfering with licensed users, but existing protocols cannot fulfill them. In particular, the medium access control (MAC) layer plays a key role in cognitive radio functions, such as channel sensing, resource allocation, spectrum mobility and spectrum sharing. To address various application-specific requirements in CRBANs, several MAC protocols have been proposed in the literature. In this paper, we survey MAC protocols for CRBANs. We then compare the different MAC protocols with one another and discuss challenging open issues in the relevant research.

  17. Modeling a content-aware LTE MAC downlink scheduler with heterogeneous traffic

    DEFF Research Database (Denmark)

    Artuso, Matteo; Christiansen, Henrik Lehrmann

    2013-01-01

    The scheduling policy adopted in the LTE (Long Term Evolution) MAC layer is the most valuable degree of freedom left from the 3GPP (3rd Generation Partnership Project) consortium to the industry and the research community . This paper presents an OPNET model of the downlink scheduling in a one...

  18. Energy Efficient MAC Scheme for Wireless Sensor Networks with High-Dimensional Data Aggregate

    Directory of Open Access Journals (Sweden)

    Seokhoon Kim

    2015-01-01

    Full Text Available This paper presents a novel and sustainable medium access control (MAC scheme for wireless sensor network (WSN systems that process high-dimensional aggregated data. Based on a preamble signal and buffer threshold analysis, it maximizes the energy efficiency of the wireless sensor devices which have limited energy resources. The proposed group management MAC (GM-MAC approach not only sets the buffer threshold value of a sensor device to be reciprocal to the preamble signal but also sets a transmittable group value to each sensor device by using the preamble signal of the sink node. The primary difference between the previous and the proposed approach is that existing state-of-the-art schemes use duty cycle and sleep mode to save energy consumption of individual sensor devices, whereas the proposed scheme employs the group management MAC scheme for sensor devices to maximize the overall energy efficiency of the whole WSN systems by minimizing the energy consumption of sensor devices located near the sink node. Performance evaluations show that the proposed scheme outperforms the previous schemes in terms of active time of sensor devices, transmission delay, control overhead, and energy consumption. Therefore, the proposed scheme is suitable for sensor devices in a variety of wireless sensor networking environments with high-dimensional data aggregate.

  19. Experimental Evaluation of Simulation Abstractions for Wireless Sensor Network MAC Protocols

    NARCIS (Netherlands)

    Halkes, G.P.; Langendoen, K.G.

    2010-01-01

    The evaluation ofMAC protocols forWireless Sensor Networks (WSNs) is often performed through simulation. These simulations necessarily abstract away from reality inmany ways. However, the impact of these abstractions on the results of the simulations has received only limited attention. Moreover,

  20. Debating Inclusion in Synecdoche, New York: A Response to Gresham and MacMillan.

    Science.gov (United States)

    Ferguson, Dianne L.; Ferguson, Philip M.

    1997-01-01

    A comprehensive review of the debate over the inclusion of children with disabilities in educational programs needs to explore research and issues beyond those considered by F. Gresham and D. MacMillan. Some of those issues are reviewed, focusing on a shift away from the medical deficit model. (SLD)

  1. The baby has not come: obstructed labour | MacKeith | South Sudan ...

    African Journals Online (AJOL)

    The baby has not come: obstructed labour. Nancy MacKeith, Wal Bichiok Wur. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's ...

  2. 76 FR 35138 - Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Risk-Based...

    Science.gov (United States)

    2011-06-16

    ... Funding and Fiscal Affairs; Farmer Mac Risk-Based Capital Stress Test, Version 5.0 AGENCY: Farm Credit... credit rating agency) in regulations addressing the Risk-Based Capital Stress Test (RBCST or stress test...) (repealing and replacing Pub. L. 110-234). B. Risk-Based Capital and Credit Ratings Under our rules, Farmer...

  3. Elevated levels of homocysteine increase IL-6 production in monocytic Mono Mac 6 cells

    NARCIS (Netherlands)

    van Aken, B. E.; Jansen, J.; van Deventer, S. J.; Reitsma, P. H.

    2000-01-01

    Hyperhomocysteinemia is a risk factor for atherosclerosis and thrombosis. The aim of this study was to analyze if exposure of monocytic cells to increased levels of homocysteine (HCY) induces the accumulation of inflammatory mediators. Interleukin (IL)-6 production by monocytic cell line Mono Mac 6

  4. Knowledge, Power, and Social Policy: John M. MacEachran and Alberta's 1928 Sexual Sterilization Act

    Science.gov (United States)

    Puplampu, Korbla P.

    2008-01-01

    This article examines how academic knowledge and power have shaped the discourse on human classification and how political authorities use academic knowledge producers to legitimize public policy. Specifically, the article draws on the role of John M. MacEachran, a former academic at the University of Alberta, in the implementation of the Alberta…

  5. 78 FR 65541 - Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Liquidity...

    Science.gov (United States)

    2013-11-01

    ... attention issues and concerns that they believe warrant further or heightened FCA scrutiny. The second...; Divide the 90-day liquidity reserve into three tiers so Farmer Mac has a sufficient amount of cash and... that can be traded at fair value and an explicit public backstop.'' From the FCA's perspective, whether...

  6. Muusikamaailm : James Levine 25 aastat Metis. Taveneri ja MacMillani millenniumiteosed. Avafestival Sydneys / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2000-01-01

    J. Harbisoni ooperi "The Great Gatsby" esmalavastusega tähistab New Yorgi Metropolitan Opera oma 25-aastast koostööd J. Levine'iga. J. Taveneri uudisteosest "The Fall and Resurrection", J. MacMillani millenniumiteose "Magnificat" maailmaesiettekandest. 5.-26. jaan. toimuvast Sydney muusikafestivalist

  7. Multiple-Antenna Interference Cancellation for WLAN with MAC Interference Avoidance in Open Access Networks

    Directory of Open Access Journals (Sweden)

    Alexandr M. Kuzminskiy

    2007-10-01

    Full Text Available The potential of multiantenna interference cancellation receiver algorithms for increasing the uplink throughput in WLAN systems such as 802.11 is investigated. The medium access control (MAC in such systems is based on carrier sensing multiple-access with collision avoidance (CSMA/CA, which itself is a powerful tool for the mitigation of intrasystem interference. However, due to the spatial dependence of received signal strengths, it is possible for the collision avoidance mechanism to fail, resulting in packet collisions at the receiver and a reduction in system throughput. The CSMA/CA MAC protocol can be complemented in such scenarios by interference cancellation (IC algorithms at the physical (PHY layer. The corresponding gains in throughput are a result of the complex interplay between the PHY and MAC layers. It is shown that semiblind interference cancellation techniques are essential for mitigating the impact of interference bursts, in particular since these are typically asynchronous with respect to the desired signal burst. Semiblind IC algorithms based on second- and higher-order statistics are compared to the conventional no-IC and training-based IC techniques in an open access network (OAN scenario involving home and visiting users. It is found that the semiblind IC algorithms significantly outperform the other techniques due to the bursty and asynchronous nature of the interference caused by the MAC interference avoidance scheme.

  8. Multiple-Antenna Interference Cancellation for WLAN with MAC Interference Avoidance in Open Access Networks

    Directory of Open Access Journals (Sweden)

    Kuzminskiy Alexandr M

    2007-01-01

    Full Text Available The potential of multiantenna interference cancellation receiver algorithms for increasing the uplink throughput in WLAN systems such as 802.11 is investigated. The medium access control (MAC in such systems is based on carrier sensing multiple-access with collision avoidance (CSMA/CA, which itself is a powerful tool for the mitigation of intrasystem interference. However, due to the spatial dependence of received signal strengths, it is possible for the collision avoidance mechanism to fail, resulting in packet collisions at the receiver and a reduction in system throughput. The CSMA/CA MAC protocol can be complemented in such scenarios by interference cancellation (IC algorithms at the physical (PHY layer. The corresponding gains in throughput are a result of the complex interplay between the PHY and MAC layers. It is shown that semiblind interference cancellation techniques are essential for mitigating the impact of interference bursts, in particular since these are typically asynchronous with respect to the desired signal burst. Semiblind IC algorithms based on second- and higher-order statistics are compared to the conventional no-IC and training-based IC techniques in an open access network (OAN scenario involving home and visiting users. It is found that the semiblind IC algorithms significantly outperform the other techniques due to the bursty and asynchronous nature of the interference caused by the MAC interference avoidance scheme.

  9. TMAC: Timestamp-Ordered MAC for CSMA/CA Wireless Mesh Networks

    KAUST Repository

    Nawab, Faisal Saud Yousef; Jamshaid, Kamran; Shihada, Basem; Ho, Pin-Han

    2011-01-01

    We propose TMAC, a timestamp-ordered MAC protocol for Wireless Mesh Networks (WMNs). TMAC extends CSMA/CA by scheduling data packets based on their age. Prior to transmitting a data packet, a transmitter broadcasts a request control message appended

  10. MAC-layer protocol for TCP fairness in Wireless Mesh Networks

    KAUST Repository

    Nawab, Faisal; Jamshaid, Kamran; Shihada, Basem; Ho, Pin-Han

    2012-01-01

    In this paper we study the interactions of TCP and IEEE 802.11 MAC in Wireless Mesh Networks (WMNs). We use a Markov chain to capture the behavior of TCP sessions, particularly the impact on network throughput performance due to the effect of queue

  11. Endotoxin testing of proteins for parenteral administration using the Mono Mac 6 assay

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, E W; Christensen, J D

    2000-01-01

    Pharmaceutical products containing proteins cause problems in testing for endotoxin and pyrogens. Many proteins interfere with the LAL test and the proteins are immunogenic in rabbits. The monocytic cell line Mono Mac 6 is an alternative assay for detection of endotoxin and other pyrogens....

  12. Implantable Body Sensor Network MAC Protocols Using Wake-up Radio – Evaluation in Animal Tissue

    NARCIS (Netherlands)

    Karuppiah Ramachandran, Vignesh Raja; van der Zwaag, B.J.; Meratnia, Nirvana; Havinga, Paul J.M.

    Applications of implantable sensor networks in the health-care industry have increased tremendously over the last decade. There are different types of medium access control (MAC) protocols that are designed for implantable body sensor networks, using different physical layer technologies such as

  13. Not the Sum of Its Parts: A Critical Review of the MacDonald Triad.

    Science.gov (United States)

    Parfitt, Charlotte Hannah; Alleyne, Emma

    2018-01-01

    The MacDonald triad posits that animal cruelty, fire setting, and bed wetting in childhood is indicative of later aggressive and violent behavior in adults. Researchers refer to this phenomenon as a precursor to later antisocial behaviors including serial and sexual murder; while practitioners cite the triad in clinical formulations and risk assessments. However, there is yet to be a critical review and consolidation of the literature that establishes whether there is empirical support. This article explores the validity of the triad. We conducted a narrative review of the relevant studies examining the MacDonald triad and its individual constituents. There is evidence that any one of the triad behaviors could predict future violent offending, but it is very rare to find all three behaviors together as predictors. Thus, the empirical research on the MacDonald triad does not fully substantiate its premise. Rather, it would appear that the triad, or its individual constituents, is better used as an indicator of dysfunctional home environments, or poor coping skills in children. Future research is needed with robust and rigorous methodologies (e.g., adequate control groups, longitudinal designs) to fully establish the MacDonald triad's validity. Finally, further consideration is needed as to whether the triad behaviors are more indicative of other problematic outcomes (e.g., maladaptive coping to life stressors).

  14. The Big Mac and Teaching about Japan. Footnotes. Volume 8, Number 5

    Science.gov (United States)

    Ellington, Lucien

    2003-01-01

    The Big Mac can be effective tool in helping students achieve a better understanding of Japan. It can defeat Orientalist stereotypes about the Japanese--and also challenge young people who might have oversimplified notions of what exactly occurs when U.S. fast food chains take root in another culture. Many deride McDonald's as a villain…

  15. Detecting DIF in Polytomous Items Using MACS, IRT and Ordinal Logistic Regression

    Science.gov (United States)

    Elosua, Paula; Wells, Craig

    2013-01-01

    The purpose of the present study was to compare the Type I error rate and power of two model-based procedures, the mean and covariance structure model (MACS) and the item response theory (IRT), and an observed-score based procedure, ordinal logistic regression, for detecting differential item functioning (DIF) in polytomous items. A simulation…

  16. Ultrasonication of pyrogenic microorganisms improves the detection of pyrogens in the Mono Mac 6 assay

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, E W; Christensen, J D

    2000-01-01

    The monocytic cell line Mono Mac 6 is sensitive to pyrogens. When exposed to pyrogens secretion of interleukin-6 is induced. However, some eukaryotic pyrogenic microorganisms are not detectable. The aim of this study is to introduce a pretreatment of samples to expand the detection range of the a...

  17. Dependence of AeroMACS Interference on Airport Radiation Pattern Characteristics

    Science.gov (United States)

    Wilson, Jeffrey D.

    2012-01-01

    AeroMACS (Aeronautical Mobile Airport Communications System), which is based upon the IEEE 802.16e mobile wireless standard, is expected to be implemented in the 5091 to 5150 MHz frequency band. As this band is also occupied by Mobile Satellite Service (MSS) feeder uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference are under analysis in order to enable the definition of standards that assure that such interference will be avoided. In this study, the cumulative interference power distribution at low earth orbit from AeroMACS transmitters at the 497 major airports in the contiguous United States was simulated with the Visualyse Professional software. The dependence of the interference power on the number of antenna beams per airport, gain patterns, and beam direction orientations was simulated. As a function of these parameters, the simulation results are presented in terms of the limitations on transmitter power required to maintain the cumulative interference power under the established threshold.

  18. 78 FR 65145 - Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Capital Planning

    Science.gov (United States)

    2013-10-31

    ... capital adequacy and capital planning. \\4\\ Bank for International Settlements, Basel Committee on Banking....60--Corporate Business Planning The Farm Credit Council commented that our reference to ``goals and.... 652.60 to read as follows: Sec. 652.60 Corporate business planning. (a) Farmer Mac's board of...

  19. Detecting and Preventing Beacon Replay Attacks in Receiver-Initiated MAC Protocols for Energy Efficient WSNs

    DEFF Research Database (Denmark)

    Di Mauro, Alessio; Fafoutis, Xenofon; Mödersheim, Sebastian Alexander

    2013-01-01

    In receiver-initiated MAC protocols for Wireless Sensor Networks (WSNs), communication is initiated by the receiver of the data through beacons containing the receiver's identity. In this paper, we consider the case of a network intruder that captures and replays such beacons towards legitimate...

  20. Nuclear power history calculation for subcritical systems using Euler-MacLaurin formula

    International Nuclear Information System (INIS)

    Henrice Junior, Edson; Goncalves, Alessandro da Cruz

    2013-01-01

    This paper presents an efficient method for calculating the reactivity using inverse point kinetic equation for subcritical systems by applying the Euler-MacLaurin summation formula to calculate the nuclear power history. In accordance with the accuracy of the numerical results, this method does not require a large number of points for calculation, providing accurate results with low computational cost. (author)

  1. Scalable Video Streaming Adaptive to Time-Varying IEEE 802.11 MAC Parameters

    Science.gov (United States)

    Lee, Kyung-Jun; Suh, Doug-Young; Park, Gwang-Hoon; Huh, Jae-Doo

    This letter proposes a QoS control method for video streaming service over wireless networks. Based on statistical analysis, the time-varying MAC parameters highly related to channel condition are selected to predict available bitrate. Adaptive bitrate control of scalably-encoded video guarantees continuity in streaming service even if the channel condition changes abruptly.

  2. Dynamic Channel Slot Allocation Scheme and Performance Analysis of Cyclic Quorum Multichannel MAC Protocol

    Directory of Open Access Journals (Sweden)

    Xing Hu

    2017-01-01

    Full Text Available In high diversity node situation, multichannel MAC protocol can improve the frequency efficiency, owing to fewer collisions compared with single-channel MAC protocol. And the performance of cyclic quorum-based multichannel (CQM MAC protocol is outstanding. Based on cyclic quorum system and channel slot allocation, it can avoid the bottleneck that others suffered from and can be easily realized with only one transceiver. To obtain the accurate performance of CQM MAC protocol, a Markov chain model, which combines the channel-hopping strategy of CQM protocol and IEEE 802.11 distributed coordination function (DCF, is proposed. The results of numerical analysis show that the optimal performance of CQM protocol can be obtained in saturation bound situation. And then we obtain the saturation bound of CQM system by bird swarm algorithm. In addition, to improve the performance of CQM protocol in unsaturation situation, a dynamic channel slot allocation of CQM (DCQM protocol is proposed, based on wavelet neural network. Finally, the performance of CQM protocol and DCQM protocol is simulated by Qualnet platform. And the simulation results show that the analytic and simulation results match very well; the DCQM performs better in unsaturation situation.

  3. A Very Low Power MAC (VLPM Protocol for Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Kyung Sup Kwak

    2011-03-01

    Full Text Available Wireless Body Area Networks (WBANs consist of a limited number of battery operated nodes that are used to monitor the vital signs of a patient over long periods of time without restricting the patient’s movements. They are an easy and fast way to diagnose the patient’s status and to consult the doctor. Device as well as network lifetime are among the most important factors in a WBAN. Prolonging the lifetime of the WBAN strongly depends on controlling the energy consumption of sensor nodes. To achieve energy efficiency, low duty cycle MAC protocols are used, but for medical applications, especially in the case of pacemakers where data have time-limited relevance, these protocols increase latency which is highly undesirable and leads to system instability. In this paper, we propose a low power MAC protocol (VLPM based on existing wakeup radio approaches which reduce energy consumption as well as improving the response time of a node. We categorize the traffic into uplink and downlink traffic. The nodes are equipped with both a low power wake-up transmitter and receiver. The low power wake-up receiver monitors the activity on channel all the time with a very low power and keeps the MCU (Micro Controller Unit along with main radio in sleep mode. When a node [BN or BNC (BAN Coordinator] wants to communicate with another node, it uses the low-power radio to send a wakeup packet, which will prompt the receiver to power up its primary radio to listen for the message that follows shortly. The wake-up packet contains the desired node’s ID along with some other information to let the targeted node to wake-up and take part in communication and let all other nodes to go to sleep mode quickly. The VLPM protocol is proposed for applications having low traffic conditions. For high traffic rates, optimization is needed. Analytical results show that the proposed protocol outperforms both synchronized and unsynchronized MAC protocols like T-MAC, SCP-MAC, B-MAC

  4. Land use

    International Nuclear Information System (INIS)

    Rickard, W.H.; Rogers, L.E.

    1977-01-01

    Justification for large land holdings at the Hanford Reservation has centered around a need for security and also as a buffer zone in the event of accidents. In recent years the importance of these large land holdings have become nationally recognized as highly desirable locations for ecological research concerning the function and structure of terrestrial ecosystems and as places to investigate the response of terrestrial ecosystems to long-term man-imposed environmental stresses. Carefully selected and protected land areas exist on the 110 square mile Arid Land Ecology Reserve (ALE) at Hanford. The projects described here provide supporting research for several applied projects that deal with environmental impact and land restoration. Information gained from this research has wide use and applicability to all kinds of energy technologies centered in the semi-arid shrub-steppe region of the northwestern United States. Ecological information reported includes: biotic characterization, including description of major habitats and endangered or threatened species; performances of native plant species, including determination of growth habits, nutrient requirements, and productivity; and, mineral cycling, including particularly the estimation of availability and behavior of airborne deposits to green plants

  5. MacA is a second cytochrome c peroxidase of Geobacter sulfurreducens.

    Science.gov (United States)

    Seidel, Julian; Hoffmann, Maren; Ellis, Katie E; Seidel, Antonia; Spatzal, Thomas; Gerhardt, Stefan; Elliott, Sean J; Einsle, Oliver

    2012-04-03

    The metal-reducing δ-proteobacterium Geobacter sulfurreducens produces a large number of c-type cytochromes, many of which have been implicated in the transfer of electrons to insoluble metal oxides. Among these, the dihemic MacA was assigned a central role. Here we have produced G. sulfurreducens MacA by recombinant expression in Escherichia coli and have solved its three-dimensional structure in three different oxidation states. Sequence comparisons group MacA into the family of diheme cytochrome c peroxidases, and the protein indeed showed hydrogen peroxide reductase activity with ABTS(-2) as an electron donor. The observed K(M) was 38.5 ± 3.7 μM H(2)O(2) and v(max) was 0.78 ± 0.03 μmol of H(2)O(2)·min(-1)·mg(-1), resulting in a turnover number k(cat) = 0.46 · s(-1). In contrast, no Fe(III) reductase activity was observed. MacA was found to display electrochemical properties similar to other bacterial diheme peroxidases, in addition to the ability to electrochemically mediate electron transfer to the soluble cytochrome PpcA. Differences in activity between CcpA and MacA can be rationalized with structural variations in one of the three loop regions, loop 2, that undergoes conformational changes during reductive activation of the enzyme. This loop is adjacent to the active site heme and forms an open loop structure rather than a more rigid helix as in CcpA. For the activation of the protein, the loop has to displace the distal ligand to the active site heme, H93, in loop 1. A H93G variant showed an unexpected formation of a helix in loop 2 and disorder in loop 1, while a M297H variant that altered the properties of the electron transfer heme abolished reductive activation.

  6. Manual Ability Classification System (MACS: reliability between therapists and parents in Brazil

    Directory of Open Access Journals (Sweden)

    Daniela B. R. Silva

    2015-02-01

    Full Text Available BACKGROUND: The Manual Ability Classification System (MACS has been widely used to describe the manual ability of children with cerebral palsy (CP; however its reliability has not been verified in Brazil. OBJECTIVE: To establish the inter- and intra-rater reliability of the Portuguese-Brazil version of the MACS by comparing the classifications given by therapists and parents of children with CP. METHOD: Data were obtained from 90 children with CP between the ages of 4 and 18 years, who were treated at the neurology and rehabilitation clinics of a Brazilian hospital. Therapists (an occupational therapist and a student classified manual ability (MACS through direct observation and information provided by parents. Therapists and parents used the Portuguese-Brazil version of the MACS. Intra- and inter-rater reliability was obtained using unweighted Kappa coefficient (k and intra-class correlation coefficient (ICC. The Chi-square test was used to identify the predominance of disagreements in the classification of parents and therapists. RESULTS: An almost perfect agreement resulted among therapists [K=0.90 (95% CI 0.83-0.97; ICC=0.97 (95%CI 0.96-0.98], as well as with intra-rater (therapists, with Kappa ranging between 0.83 and 0.95 and ICC between 0.96 and 0.99 for the evaluator with more and less experience in rehabilitation, respectively. The agreement between therapists and parents was fair [K=0.36 (95% CI 0.22-0.50; ICC=0.79 (95% CI 0.70-0.86]. CONCLUSIONS: The Portuguese version of the MACS is a reliable instrument to be used jointly by parents and therapists.

  7. Assessment of manual material handling using Iranian MMH regulations and comparison with NIOSH equation and MAC method in one of the metal casting industries in Tehran, 2011

    Directory of Open Access Journals (Sweden)

    2013-08-01

    Result: Results showed an acceptable agreement between Iranian regulation and MAC method as well as Iranian regulation and NIOSH equation. However, no acceptable agreement was observed between MAC method and NIOSH equation.

  8. Living Lands

    DEFF Research Database (Denmark)

    Christensen, Suna Møller

    2015-01-01

    , hunters attended to questions like safe-journeying on ice or the role of natural surroundings in children’s education, in ways revealing a relational perception of ‘nature’ and dissolving culture-nature dualisms. Hunters’ experiences in living the land afforded children a dwelling position from which...... to grow with the features of the land. Framed this way, ‘nature’ was regarded as part of the social world. I suggest that learning among Arctic hunters is social and twofold. First, we can learn how human-environment relations influence individual life trajectories. Secondly, ‘nature’ as part...

  9. THE ISOLATION AND IDENTIFICATION OF MYCOBACTERIUM AVIUM COMPLEX (MAC) RECOVERED FROM LOS ANGELES POTABLE WATER, A POSSIBLE SOURCE OF INFECTION IN AIDS PATIENTS

    Science.gov (United States)

    Los Angeles water was investigated as a possible source of Mycobacterium avium complex (MAC) infection in patients with AIDS. MAC consists of M.avium (MA), M. intracellulare (MI) and Mycobacterium X (MX)(positive for MAC by DNA probe but not MA or MI). The study included 13 reser...

  10. [Spanish validation of the MacArthur Competence Assessment Tool for Treatment interview to assess patients competence to consent treatment].

    Science.gov (United States)

    Alvarez Marrodán, Ignacio; Baón Pérez, Beatriz; Navío Acosta, Mercedes; López-Antón, Raul; Lobo Escolar, Elena; Ventura Faci, Tirso

    2014-09-09

    To validate the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) Spanish version, which assesses the mental capacity of patients to consent treatment, by examining 4 areas (Understanding, Appreciation, Reasoning and Expressing a choice). 160 subjects (80 Internal Medicine inpatients, 40 Psychiatric inpatients and 40 healthy controls). MacCAT-T, Mini-Mental Status Examination (MMSE). Feasibility study, reliability and validity calculations (against to gold standard of clinical expert). Mean duration of the MacCAT-T interview was 18min. Inter-rater reliability: Intraclass correlation coefficient for Understanding=0.98, Appreciation=0.97, Reasoning=0.98, Expressing a choice=0.91. Internal consistency (Cronbach's alpha): Understanding=0.87, for Appreciation=0.76, for Reasoning=0.86. Patients considered to be incapable (gold standard) scored lower in all the MacCAT-T areas. Poor performance on the MacCAT-T was related to cognitive impairment assessed by MMSE. Spanish version of the MacCAT-T is feasible, reliable, and valid for assessing the capacity of patients to consent treatment. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  11. Matrix-assisted cocrystallization (MAC) simultaneous production and formulation of pharmaceutical cocrystals by hot-melt extrusion.

    Science.gov (United States)

    Boksa, Kevin; Otte, Andrew; Pinal, Rodolfo

    2014-09-01

    A novel method for the simultaneous production and formulation of pharmaceutical cocrystals, matrix-assisted cocrystallization (MAC), is presented. Hot-melt extrusion (HME) is used to create cocrystals by coprocessing the drug and coformer in the presence of a matrix material. Carbamazepine (CBZ), nicotinamide (NCT), and Soluplus were used as a model drug, coformer, and matrix, respectively. The MAC product containing 80:20 (w/w) cocrystal:matrix was characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy, and powder X-ray diffraction. A partial least squares (PLS) regression model was developed for quantifying the efficiency of cocrystal formation. The MAC product was estimated to be 78% (w/w) cocrystal (theoretical 80%), with approximately 0.3% mixture of free (unreacted) CBZ and NCT, and 21.6% Soluplus (theoretical 20%) with the PLS model. A physical mixture (PM) of a reference cocrystal (RCC), prepared by precipitation from solution, and Soluplus resulted in faster dissolution relative to the pure RCC. However, the MAC product with the exact same composition resulted in considerably faster dissolution and higher maximum concentration (∼five-fold) than those of the PM. The MAC product consists of high-quality cocrystals embedded in a matrix. The processing aspect of MAC plays a major role on the faster dissolution observed. The MAC approach offers a scalable process, suitable for the continuous manufacturing and formulation of pharmaceutical cocrystals. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  12. Short-term hydro generation scheduling of Three Gorges–Gezhouba cascaded hydropower plants using hybrid MACS-ADE approach

    International Nuclear Information System (INIS)

    Mo, Li; Lu, Peng; Wang, Chao; Zhou, Jianzhong

    2013-01-01

    Highlights: • MACS and ADE algorithms are hybridized as MACS-ADE method for solving STHGS problem. • An adaptive mutation is integrated into the proposed algorithm to avoid premature convergence. • MACS and ADE are run in parallel in search of better solution. • Several effective heuristic strategies are designed for dealing with various constraints of STHGS problem. - Abstract: Short-term hydro generation scheduling (STHGS) aims at determining optimal hydro generation scheduling to obtain minimum water consumption for one day or week while meeting various system constraints. In this paper, the STHGS problem is decomposed into two sub-problems: (i) unit commitment (UC) sub-problem; (ii) economic load dispatch (ELD) sub-problem. Then, we present a hybrid algorithm based on multi ant colony system (MACS) and differential evolution (DE) for solving the STHGS problem. First, MACS is used for dealing with UC sub-problem. A set of cooperating ant colonies cooperate to choose the unit state over the scheduled time horizon. Then, the adaptive differential evolution (ADE) is used to solve ELD sub-problem. MACS and ADE are run in parallel with adjusting their solutions in search of a better solution. Meanwhile, local and global pheromone updating rules in MACS and adaptive dynamic parameter adjusting strategy in DE are applied for enhancing the search ability of MACS-ADE. Finally, the proposed method is implemented to solve STHGS problem of Three Gorges–Gezhouba cascaded hydropower plants to verify the feasibility and effectiveness. Compared with other established methods, the simulation results reveal that the proposed MACS-ADE approach has the best convergence property, computational efficiency with less water consumption

  13. What are the key drivers of MAC curves? A partial-equilibrium modelling approach for the UK

    International Nuclear Information System (INIS)

    Kesicki, Fabian

    2013-01-01

    Marginal abatement cost (MAC) curves are widely used for the assessment of costs related to CO 2 emissions reduction in environmental economics, as well as domestic and international climate policy. Several meta-analyses and model comparisons have previously been performed that aim to identify the causes for the wide range of MAC curves. Most of these concentrate on general equilibrium models with a focus on aspects such as specific model type and technology learning, while other important aspects remain almost unconsidered, including the availability of abatement technologies and level of discount rates. This paper addresses the influence of several key parameters on MAC curves for the United Kingdom and the year 2030. A technology-rich energy system model, UK MARKAL, is used to derive the MAC curves. The results of this study show that MAC curves are robust even to extreme fossil fuel price changes, while uncertainty around the choice of the discount rate, the availability of key abatement technologies and the demand level were singled out as the most important influencing factors. By using a different model type and studying a wider range of influencing factors, this paper contributes to the debate on the sensitivity of MAC curves. - Highlights: ► A partial-equilibrium model is employed to test key sensitivities of MAC curves. ► MAC curves are found to be robust to wide-ranging changes in fossil fuel prices. ► Most influencing factors are the discount rate, availability of key technologies. ► Further important uncertainty in MAC curves is related to demand changes

  14. The wave equation in Friedmann-Robertson-Walker space-times and asymptotics of the intensity and distance relationship of a localised source

    Science.gov (United States)

    Starko, Darij; Craig, Walter

    2018-04-01

    Variations in redshift measurements of Type 1a supernovae and intensity observations from large sky surveys are an indicator of a component of acceleration in the rate of expansion of space-time. A key factor in the measurements is the intensity-distance relation for Maxwell's equations in Friedmann-Robertson-Walker (FRW) space-times. In view of future measurements of the decay of other fields on astronomical time and spatial scales, we determine the asymptotic behavior of the intensity-distance relationship for the solution of the wave equation in space-times with an FRW metric. This builds on previous work done on initial value problems for the wave equation in FRW space-time [Abbasi, B. and Craig, W., Proc. R. Soc. London, Ser. A 470, 20140361 (2014)]. In this paper, we focus on the precise intensity decay rates of the special cases for curvature k = 0 and k = -1, as well as giving a general derivation of the wave solution for -∞ 0} where t0 represents the time of an initial emission source, relative to the Big Bang singularity at t = 0. The initial data [g(x), h(x)] are assumed to be compactly supported; supp(g, h) ⊆ BR(0) and terms in the expression for the fundamental solution for the wave equation with the slowest decay rate are retained. The intensities calculated for coordinate time {t : t > 0} contain correction terms proportional to the ratio of t0 and the time differences ρ = t - t0. For the case of general curvature k, these expressions for the intensity reduce by scaling to the same form as for k = -1, from which we deduce the general formula. We note that for typical astronomical events such as Type 1a supernovae, the first order correction term for all curvatures -∞ < k < 0 is on the order of 10-4 smaller than the zeroth order term. These correction terms are small but may be significant in applications to alternative observations of cosmological space-time expansion rates.

  15. The Big Mac Index: A Shortcut To Inflation And Exchange Rate Dynamics? Price Tracking And Predictive Properties

    OpenAIRE

    Luis San Vicente Portes; Vidya Atal

    2014-01-01

    The Economist magazine has been publishing the Big Mac Index using it as a rule of thumb to determine the over- or under-valuation of international currencies based on the theory of Purchasing Power Parity since 1986. According to the theory, using the Big Mac as a tradable single-good basket, the Dollar-value of the hamburger should be equalized around the world due to arbitrage. The popularity and following of the Big Mac Index led the authors to the following two questions: 1) How effectiv...

  16. Annie Marion MacLean: “the mother of contemporary etnography” and pioneer in sociology distance learning

    Directory of Open Access Journals (Sweden)

    Silvia García Dauder

    2008-05-01

    Full Text Available The article introduces Anne Marion MacLean into the United States' scientific sociology at its very origins (1892, when the Department of Sociology of the Chicago University was created. It also puts MacLean in a network called "Women's School of Chicago", and the forgotten contributions of these social sciences' pioneers, submitted to the American Journal of Sociology, are analyzed. Two MacLean's key contributions are highlighted: the correspondence courses in teaching sociology and her research by means of participant observation in workplaces focusing on women's work.

  17. Review of Sustainable Energy -- Without the Hot Air by David MacKay (2009

    Directory of Open Access Journals (Sweden)

    Kira Hamman

    2016-07-01

    Full Text Available David MacKay. Sustainable Energy: Without the hot air. (Cambridge, England: UIT Cambridge Ltd., 2009. 384 pp. ISBN 978-0954452933 (also available as a free e-book. Physicist David MacKay transforms what has historically been a debate fraught with skepticism and hysteria into an informed conversation. He does this by providing clear, accurate quantitative information on energy production and consumption in a form that allows comparison and invites thoughtful analysis. By recalibrating power into kilowatt-hours per day per person, he makes the numbers meaningful on an individual level. He then meticulously estimates the productive capacity of various renewable energy sources, explores alternative energy solutions, and ends with an array of concrete plans to get the planet off fossil fuels for good.

  18. Application of the implicit MacCormack scheme to the parabolized Navier-Stokes equations

    Science.gov (United States)

    Lawrence, J. L.; Tannehill, J. C.; Chaussee, D. S.

    1984-01-01

    MacCormack's implicit finite-difference scheme was used to solve the two-dimensional parabolized Navier-Stokes (PNS) equations. This method for solving the PNS equations does not require the inversion of block tridiagonal systems of algebraic equations and permits the original explicit MacCormack scheme to be employed in those regions where implicit treatment is not needed. The advantages and disadvantages of the present adaptation are discussed in relation to those of the conventional Beam-Warming scheme for a flat plate boundary layer test case. Comparisons are made for accuracy, stability, computer time, computer storage, and ease of implementation. The present method was also applied to a second test case of hypersonic laminar flow over a 15% compression corner. The computed results compare favorably with experiment and a numerical solution of the complete Navier-Stokes equations.

  19. Objective-C for Absolute Beginners iPhone and Mac Programming Made Easy

    CERN Document Server

    Bennett, Gary; Fisher, Mitchell

    2010-01-01

    It seems as if everyone is writing applications for Apple's iPhone and iPad, but how do they all do it? It's best to learn Objective-C, the native language of both the iOS and Mac OS X, but where to begin? Right here, even if you've never programmed before! Objective-C for Absolute Beginners will teach you how to write software for your Mac, iPhone,or iPad using Objective-C, an elegant and powerful language with a rich set of developer tools. Using a hands-on approach, you'll learn to think in programming terms, how to use Objective-C to build program logic, and how to write your own applicati

  20. Obtaining porous silicon suitable for sensor technology using MacEtch nonelectrolytic etching

    Directory of Open Access Journals (Sweden)

    Iatsunskyi I. R.

    2013-12-01

    Full Text Available The author suggests to use the etching method MacEtch (metal-assisted chemical etching for production of micro- and nanostructures of porous silicon. The paper presents research results on the morphology structures obtained at different parameters of deposition and etching processes. The research has shown that, depending on the parameters of deposition of silver particles and silicon wafers etching, the obtained surface morphology may be different. There may be both individual crater-like pores and developed porous or macroporous surface. These results indicate that the MacEtch etching is a promising method for obtaining micro-porous silicon nanostructures suitable for effective use in gas sensors and biological object sensors.

  1. A comparative study of upwind and MacCormack schemes for CAA benchmark problems

    Science.gov (United States)

    Viswanathan, K.; Sankar, L. N.

    1995-01-01

    In this study, upwind schemes and MacCormack schemes are evaluated as to their suitability for aeroacoustic applications. The governing equations are cast in a curvilinear coordinate system and discretized using finite volume concepts. A flux splitting procedure is used for the upwind schemes, where the signals crossing the cell faces are grouped into two categories: signals that bring information from outside into the cell, and signals that leave the cell. These signals may be computed in several ways, with the desired spatial and temporal accuracy achieved by choosing appropriate interpolating polynomials. The classical MacCormack schemes employed here are fourth order accurate in time and space. Results for categories 1, 4, and 6 of the workshop's benchmark problems are presented. Comparisons are also made with the exact solutions, where available. The main conclusions of this study are finally presented.

  2. An FEC Adaptive Multicast MAC Protocol for Providing Reliability in WLANs

    Science.gov (United States)

    Basalamah, Anas; Sato, Takuro

    For wireless multicast applications like multimedia conferencing, voice over IP and video/audio streaming, a reliable transmission of packets within short delivery delay is needed. Moreover, reliability is crucial to the performance of error intolerant applications like file transfer, distributed computing, chat and whiteboard sharing. Forward Error Correction (FEC) is frequently used in wireless multicast to enhance Packet Error Rate (PER) performance, but cannot assure full reliability unless coupled with Automatic Repeat Request forming what is knows as Hybrid-ARQ. While reliable FEC can be deployed at different levels of the protocol stack, it cannot be deployed on the MAC layer of the unreliable IEEE802.11 WLAN due to its inability to exchange ACKs with multiple recipients. In this paper, we propose a Multicast MAC protocol that enhances WLAN reliability by using Adaptive FEC and study it's performance through mathematical analysis and simulation. Our results show that our protocol can deliver high reliability and throughput performance.

  3. A Reconfigurable Design and Architecture of the Ethernet and HomePNA3.0 MAC

    Science.gov (United States)

    Khalilydermany, M.; Hosseinghadiry, M.

    In this paper a reconfigurable architecture for Ethernet and HomePNA MAC is presented. By using this new architecture, Ethernet and HomePNA reconfigurable network card can be produced. This architecture has been implemented using VHDL language and after that synthesized on a chip. The differences between HomePNA (synchronized and unsynchronized mode) and Ethernet in collision detection mechanism and priority access to media have caused the need to separate architectures for Ethernet and HomePNA, but by using similarities of them, both the Ethernet and the HomePNA can be implemented in a single chip with a little extra hardware. The number of logical elements of the proposed architecture is increased by 19% in compare to when only an Ethernet MAC is implemented

  4. Global Mobile Satellite Service Interference Analysis for the AeroMACS

    Science.gov (United States)

    Wilson, Jeffrey D.; Apaza, Rafael D.; Hall, Ward; Phillips, Brent

    2013-01-01

    The AeroMACS (Aeronautical Mobile Airport Communications System), which is based on the IEEE 802.16-2009 mobile wireless standard, is envisioned as the wireless network which will cover all areas of airport surfaces for next generation air transportation. It is expected to be implemented in the 5091-5150 MHz frequency band which is also occupied by mobile satellite service uplinks. Thus the AeroMACS must be designed to avoid interference with this incumbent service. Simulations using Visualyse software were performed utilizing a global database of 6207 airports. Variations in base station and subscriber antenna distribution and gain pattern were examined. Based on these simulations, recommendations for global airport base station and subscriber antenna power transmission limitations are provided.

  5. A Novel Video Data-Source Authentication Model Based on Digital Watermarking and MAC in Multicast

    Institute of Scientific and Technical Information of China (English)

    ZHAO Anjun; LU Xiangli; GUO Lei

    2006-01-01

    A novel video data authentication model based on digital video watermarking and MAC (message authentication code) in multicast protocol is proposed in this paper. The digital watermarking which composes of the MAC of the significant video content, the key and instant authentication data is embedded into the insignificant video component by the MLUT (modified look-up table) video watermarking technology. We explain a method that does not require storage of each data packet for a time, thus making receiver not vulnerable to DOS (denial of service) attack. So the video packets can be authenticated instantly without large volume buffer in the receivers. TESLA(timed efficient stream loss-tolerant authentication) does not explain how to select the suitable value for d, which is an important parameter in multicast source authentication. So we give a method to calculate the key disclosure delay (number of intervals). Simulation results show that the proposed algorithms improve the performance of data source authentication in multicast.

  6. Le meurtre du prêtre comme violence inaugurale (Bulgarie 1872, Macédoine 1900)

    OpenAIRE

    Lory, Bernard

    2010-01-01

    Quand la violence révolutionnaire se retourne-t-elle contre la communauté qu'elle prétend promouvoir ? Enquêtant sur les premiers Bulgares exécutés par le Comité Central Révolutionnaire Bulgare et les premiers Macédoniens exécutés par l'Organisation Révolutionnaire Intérieure Macédonienne, cet article analyse deux épisodes qui présentent des analogies frappantes. En 1872, le diacre Paisij est assassiné à Orhanie dans des circonstances troublantes, puisque ce meurtre a été annoncé par deux rêv...

  7. Mario Sironi nas chamadas Coleções Matarazzo do MAC USP

    Directory of Open Access Journals (Sweden)

    Andrea Ronqui

    Full Text Available O acervo de arte moderna italiana do MAC-USP pode ser considerado a maior coleção desse gênero fora da Itália e vem sendo objeto de estudo nos últimos anos. Das 71 obras italianas, seis são de autoria de Mario Sironi. Este artigo propõe uma apresentação do percurso do artista, com breve análise de sua evolução pictórica, a partir dos estudos já existentes, a fim de situar as obras sironianas do acervo do MAC no contexto de sua produção.

  8. Persistent RCSMA: A MAC Protocol for a Distributed Cooperative ARQ Scheme in Wireless Networks

    Directory of Open Access Journals (Sweden)

    J. Alonso-Zárate

    2008-05-01

    Full Text Available The persistent relay carrier sensing multiple access (PRCSMA protocol is presented in this paper as a novel medium access control (MAC protocol that allows for the execution of a distributed cooperative automatic retransmission request (ARQ scheme in IEEE 802.11 wireless networks. The underlying idea of the PRCSMA protocol is to modify the basic rules of the IEEE 802.11 MAC protocol to execute a distributed cooperative ARQ scheme in wireless networks in order to enhance their performance and to extend coverage. A closed formulation of the distributed cooperative ARQ average packet transmission delay in a saturated network is derived in the paper. The analytical equations are then used to evaluate the performance of the protocol under different network configurations. Both the accuracy of the analysis and the performance evaluation of the protocol are supported and validated through computer simulations.

  9. Make your own video with QuickTime on the Mac

    CERN Document Server

    CERN. Geneva

    2016-01-01

    A step-by-step video tutorial on how to do a screen recording using QuickTime player on a Mac. QuickTime is a multimedia framework, which is natively installed on most Mac computers. This tutorial explains how to do a screen recording using Quicktime and how to export the video. A pdf document on the subject is available as material from the indico event page. Tell us what you think via e-learning.support at cern.ch More tutorials in the e-learning collection of the CERN Document Server (CDS) http://cds.cern.ch/collection/E-learning%20modules?ln=en All info about the CERN rapid e-learning project is linked from http://twiki.cern.ch/ELearning  

  10. Multiple lupus-associated ITGAM variants alter Mac-1 functions on neutrophils.

    Science.gov (United States)

    Zhou, Yebin; Wu, Jianming; Kucik, Dennis F; White, Nathan B; Redden, David T; Szalai, Alexander J; Bullard, Daniel C; Edberg, Jeffrey C

    2013-11-01

    Multiple studies have demonstrated that single-nucleotide polymorphisms (SNPs) in the ITGAM locus (including the nonsynonymous SNPs rs1143679, rs1143678, and rs1143683) are associated with systemic lupus erythematosus (SLE). ITGAM encodes the protein CD11b, a subunit of the β2 integrin Mac-1. The purpose of this study was to determine the effects of ITGAM genetic variation on the biologic functions of neutrophil Mac-1. Neutrophils from ITGAM-genotyped and -sequenced healthy donors were isolated for functional studies. The phagocytic capacity of neutrophil ITGAM variants was probed with complement-coated erythrocytes, serum-treated zymosan, heat-treated zymosan, and IgG-coated erythrocytes. The adhesion capacity of ITGAM variants, in adhering to either purified intercellular adhesion molecule 1 or tumor necrosis factor α-stimulated endothelial cells, was assessed in a flow chamber. Expression levels of total CD11b and activation of CD11b were assessed by flow cytometry. Mac-1-mediated neutrophil phagocytosis, determined in cultures with 2 different complement-coated particles, was significantly reduced in individuals with nonsynonymous variant alleles of ITGAM. This reduction in phagocytosis was related to variation at either rs1143679 (in the β-propeller region) or rs1143678/rs1143683 (highly linked SNPs in the cytoplasmic/calf-1 regions). Phagocytosis mediated by Fcγ receptors was also significantly reduced in donors with variant ITGAM alleles. Similarly, firm adhesion of neutrophils was significantly reduced in individuals with variant ITGAM alleles. These functional alterations were not attributable to differences in total receptor expression or activation. The nonsynonymous ITGAM variants rs1143679 and rs1143678/rs113683 contribute to altered Mac-1 function on neutrophils. These results underscore the need to consider multiple nonsynonymous SNPs when assessing the functional consequences of ITGAM variation on immune cell processes and the risk of SLE

  11. Does PPP hold for Big Mac price or consumer price index? Evidence from panel cointegration

    OpenAIRE

    Chien-Fu Chen; Chung-Hua Shen; Chien-An Wang

    2007-01-01

    This paper examines the validity of purchasing power parity (PPP) using CPI and Big Mac prices. The benchmark model, i.e., the OLS method, which does not take nonstationarity into account, rejects the hypothesis of PPP regardless of prices used. We next use the panel cointegration method to consider the nonstationary nature of variables. Estimated results for CPI are mixed. The PPP is rejected when the nominal exchange rate is employed as the dependent variable but is not rejected when the pr...

  12. Metabolome and fecal microbiota in monozygotic twin pairs discordant for weight: a Big Mac challenge

    OpenAIRE

    Bondia-Pons, Isabel; Maukonen, Johanna; Mattila, Ismo; Rissanen, Aila; Saarela, Maria; Kaprio, Jaakko; Hakkarainen, Antti; Lundbom, Jesper; Lundbom, Nina; Hy?tyl?inen, Tuulia; Pietil?inen, Kirsi H.; Ore?i?, Matej

    2014-01-01

    Postprandial responses to food are complex, involving both genetic and environmental factors. We studied postprandial responses to a Big Mac meal challenge in monozygotic co-twins highly discordant for body weight. This unique design allows assessment of the contribution of obesity, independent of genetic liability. Comprehensive metabolic profiling using 3 analytical platforms was applied to fasting and postprandial serum samples from 16 healthy monozygotic twin pairs discordant for weight (...

  13. Microfabricated inserts for magic angle coil spinning (MACS wireless NMR spectroscopy.

    Directory of Open Access Journals (Sweden)

    Vlad Badilita

    Full Text Available This article describes the development and testing of the first automatically microfabricated probes to be used in conjunction with the magic angle coil spinning (MACS NMR technique. NMR spectroscopy is a versatile technique for a large range of applications, but its intrinsically low sensitivity poses significant difficulties in analyzing mass- and volume-limited samples. The combination of microfabrication technology and MACS addresses several well-known NMR issues in a concerted manner for the first time: (i reproducible wafer-scale fabrication of the first-in-kind on-chip LC microresonator for inductive coupling of the NMR signal and reliable exploitation of MACS capabilities; (ii improving the sensitivity and the spectral resolution by simultaneous spinning the detection microcoil together with the sample at the "magic angle" of 54.74° with respect to the direction of the magnetic field (magic angle spinning - MAS, accompanied by the wireless signal transmission between the microcoil and the primary circuit of the NMR spectrometer; (iii given the high spinning rates (tens of kHz involved in the MAS methodology, the microfabricated inserts exhibit a clear kinematic advantage over their previously demonstrated counterparts due to the inherent capability to produce small radius cylindrical geometries, thus tremendously reducing the mechanical stress and tearing forces on the sample. In order to demonstrate the versatility of the microfabrication technology, we have designed MACS probes for various Larmor frequencies (194, 500 and 700 MHz testing several samples such as water, Drosophila pupae, adamantane solid and LiCl at different magic angle spinning speeds.

  14. Pulmonary symptoms and diagnoses are associated with HIV in the MACS and WIHS cohorts.

    Science.gov (United States)

    Gingo, Matthew R; Balasubramani, Goundappa K; Rice, Thomas B; Kingsley, Lawrence; Kleerup, Eric C; Detels, Roger; Seaberg, Eric C; Greenblatt, Ruth M; Holman, Susan; Huang, Laurence; Sutton, Sarah H; Bertolet, Marnie; Morris, Alison

    2014-04-30

    Several lung diseases are increasingly recognized as comorbidities with HIV; however, few data exist related to the spectrum of respiratory symptoms, diagnostic testing, and diagnoses in the current HIV era. The objective of the study is to determine the impact of HIV on prevalence and incidence of respiratory disease in the current era of effective antiretroviral treatment. A pulmonary-specific questionnaire was administered yearly for three years to participants in the Multicenter AIDS Cohort Study (MACS) and Women's Interagency HIV Study (WIHS). Adjusted prevalence ratios for respiratory symptoms, testing, or diagnoses and adjusted incidence rate ratios for diagnoses in HIV-infected compared to HIV-uninfected participants were determined. Risk factors for outcomes in HIV-infected individuals were modeled. Baseline pulmonary questionnaires were completed by 907 HIV-infected and 989 HIV-uninfected participants in the MACS cohort and by 1405 HIV-infected and 571 HIV-uninfected participants in the WIHS cohort. In MACS, dyspnea, cough, wheezing, sleep apnea, and incident chronic obstructive pulmonary disease (COPD) were more common in HIV-infected participants. In WIHS, wheezing and sleep apnea were more common in HIV-infected participants. Smoking (MACS and WIHS) and greater body mass index (WIHS) were associated with more respiratory symptoms and diagnoses. While sputum studies, bronchoscopies, and chest computed tomography scans were more likely to be performed in HIV-infected participants, pulmonary function tests were no more common in HIV-infected individuals. Respiratory symptoms in HIV-infected individuals were associated with history of pneumonia, cardiovascular disease, or use of HAART. A diagnosis of asthma or COPD was associated with previous pneumonia. In these two cohorts, HIV is an independent risk factor for several respiratory symptoms and pulmonary diseases including COPD and sleep apnea. Despite a higher prevalence of chronic respiratory symptoms

  15. Environmental Assessment for Construction of Radial Arm Spill Gates MacDill Air Force Base, Florida

    Science.gov (United States)

    2012-05-01

    chromates . A detailed tracking and accounting system is in place to identify potentially hazardous materials and to ensure that MacDill AFB organizations...compressed gases, pesticides, herbicides, nitrates, and chromates . A detailed tracking and accounting system is in place to identify potentially...County, Florida Before the undersigned authority personally appeared C. Pugh, who on oath says that she is the Advertising Billing Analyst of The

  16. Optimization of hybrid token-CDMA MAC system using cross-layer information

    CSIR Research Space (South Africa)

    Liu, I-S

    2007-08-01

    Full Text Available The hybrid MAC scheme is capable to implement in either ad hoc or wireless mesh networks (WMN). For WMN configuration, stations are served as access networks utilizing non-mobile relaying nodes to provide wireless backbone services for nomadic users... University and a PhD degree from University of Cambridge, United Kingdom. His research interests are in the general areas of adaptive signal processing, digital and wireless communications and data networks. Co-author: Professor Hong-Jun Xu...

  17. Patients with MAC Lung Disease Have a Low Visceral Fat Area and Low Nutrient Intake

    Directory of Open Access Journals (Sweden)

    Kentaro Wakamatsu

    2015-01-01

    Full Text Available Objective. This study aimed to examine the nutritional status and nutrient intake of patients with MAC lung disease with a focus on visceral fat area. Patients and Methods. Among 116 patients of our hospital with nontuberculous mycobacteriosis who were registered between May 2010 and August 2011, 103 patients with MAC lung disease were included in this study. In all patients, nutritional status and nutrient intake were prospectively examined. Results. Patients were 23 men and 80 women (mean age, 72.3±10.9 years. BMI (kg/m2 at the time of registration was 20.4±2.7 in men and 19.2±2.9 in women. Visceral fat area (cm2 was significantly lower in women (35.7±26.6 than in men (57.5±47.4 (p=0.0111. The comparison with general healthy adults according to age revealed a markedly reduced visceral fat area among patients with MAC lung disease. With respect to nutrient intake, energy adequacy (86.1±15.7%, protein adequacy (82.4±18.2%, lipid adequacy (78.1±21.8%, and carbohydrate adequacy (89.6±19.2% ratios were all low at the time of registration. BMI was significantly correlated with protein adequacy (p=0.0397 and lipid adequacy (p=0.0214 ratios, while no association was found between visceral fat area and nutrient intake. Conclusion. Patients with MAC lung disease had a low visceral fat area and low nutrient intake.

  18. Four Unknown Prison Poems by H. C. Bosman | MacKenzie ...

    African Journals Online (AJOL)

    Four Unknown Prison Poems by H. C. Bosman. C MacKenzie. Abstract. No Abstract. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/eia.v40i2.1 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors ...

  19. Enhancing MAC performance of DCF protocol for IEEE 802.11 wireless LANs

    Science.gov (United States)

    Choi, Woo-Yong

    2017-01-01

    The DCF (Distributed Coordination Function) is the basic MAC (Medium Access Control) protocol of IEEE 802.11 wireless LANs and compatible with various IEEE 802.11 PHY extensions. The performance of the DCF degrades exponentially as the number of nodes participating in the DCF transmission procedure increases. To deal with this problem, we propose a simple, however efficient modification of the DCF by which the performance of the DCF is greatly enhanced.

  20. The Long-Run Value of Currencies: A Big Mac Perspective

    OpenAIRE

    Yihui Lan

    2001-01-01

    Purchasing Power Parity (PPP), the link between exchange rates and prices, is a fundamental building block of international finance, one which has been attracting increasing research interest during the past three decades. The Big Mac Index (BMI), invented by 'The Economist' magazine in 1986, has played a major role in popularising PPP and bringing its practical implications to the attention of financial markets. The aim of this paper is to derive long-run equilibrium values of currencies usi...

  1. Stochastic simulation of climate change impacts on ice road operations, MacKenzie River, Northwest Territories

    International Nuclear Information System (INIS)

    Woo, Mingko; Lonergan, S.

    1990-01-01

    Winter roads constitute an important part of the transportation network in the MacKenzie Delta, the Yellowknife area, and between the MacKenzie Highway and the Canol Road. Climatic changes in the MacKenzie Valley will alter the probabilities of ice cover thickness and duration, impacting on the periods when ice road river crossings are viable. Stochastic models were developed to generate air temperature and precipitation data to analyze climate impacts on when ice road crossing of the MacKenzie River at Norman Wells is feasible. The data were employed to simulate river ice growth and decay. Several general circulation models were employed to determine the impacts of climatic change on the ice regime. For precipitation simulation, the occurrence of wet or dry days was determined from Markov chain transition probabilities. In general, the Goddard Institute of Space Studies (GISS) model predicted the largest increase in monthly precipitation and the Oregon State University (OSU) model predicted the least changes. The various scenarios indicated that the duration for vehicular traffic over ice will be significantly reduced, compared to present day Norman Wells ice crossing operation. For 20 tonne vehicles, the current duration for safe crossing averages 169±14.6 days per year, while for the OSU scenario it will be reduced to 148±14.7 days, is further reduced to 127±24.9 days for the GISS scenario, and drops to 122±21.7 days for the GFDL (General Fluid Dynamics Laboratory) scenario. 5 refs., 1 fig

  2. An Efficient and QoS Supported Multichannel MAC Protocol for Vehicular Ad Hoc Networks.

    Science.gov (United States)

    Song, Caixia; Tan, Guozhen; Yu, Chao

    2017-10-09

    Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety (transport efficiency and infotainment) applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. Different types of applications require different levels Quality-of-Service (QoS) support. Recently, transport efficiency and infotainment applications (e.g., electronic map download and Internet access) have received more and more attention, and this kind of applications is expected to become a big market driver in a near future. In this paper, we propose an Efficient and QoS supported Multichannel Medium Access Control (EQM-MAC) protocol for VANETs in a highway environment. The EQM-MAC protocol utilizes the service channel resources for non-safety message transmissions during the whole synchronization interval, and it dynamically adjusts minimum contention window size for different non-safety services according to the traffic conditions. Theoretical model analysis and extensive simulation results show that the EQM-MAC protocol can support QoS services, while ensuring the high saturation throughput and low transmission delay for non-safety applications.

  3. An Efficient and QoS Supported Multichannel MAC Protocol for Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Caixia Song

    2017-10-01

    Full Text Available Vehicular Ad Hoc Networks (VANETs employ multichannel to provide a variety of safety and non-safety (transport efficiency and infotainment applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. Different types of applications require different levels Quality-of-Service (QoS support. Recently, transport efficiency and infotainment applications (e.g., electronic map download and Internet access have received more and more attention, and this kind of applications is expected to become a big market driver in a near future. In this paper, we propose an Efficient and QoS supported Multichannel Medium Access Control (EQM-MAC protocol for VANETs in a highway environment. The EQM-MAC protocol utilizes the service channel resources for non-safety message transmissions during the whole synchronization interval, and it dynamically adjusts minimum contention window size for different non-safety services according to the traffic conditions. Theoretical model analysis and extensive simulation results show that the EQM-MAC protocol can support QoS services, while ensuring the high saturation throughput and low transmission delay for non-safety applications.

  4. ASAP: A MAC Protocol for Dense and Time-Constrained RFID Systems

    Directory of Open Access Journals (Sweden)

    Kyounghwan Lee

    2007-08-01

    Full Text Available We introduce a novel medium access control (MAC protocol for radio frequency identification (RFID systems which exploits the statistical information collected at the reader. The protocol, termed adaptive slotted ALOHA protocol (ASAP, is motivated by the need to significantly improve the total read time performance of the currently suggested MAC protocols for RFID systems. In order to accomplish this task, ASAP estimates the dynamic tag population and adapts the frame size in the subsequent round via a simple policy that maximizes an appropriately defined efficiency function. We demonstrate that ASAP provides significant improvement in total read time performance over the current RFID MAC protocols. We next extend the design to accomplish reliable performance of ASAP in realistic scenarios such as the existence of constraints on frame size, and mobile RFID systems where tags move at constant velocity in the reader's field. We also consider the case where tags may fail to respond because of a physical breakdown or a temporary malfunction, and show the robustness in those scenarios as well.

  5. CoCoMac 2.0 and the future of tract-tracing databases

    Directory of Open Access Journals (Sweden)

    Rembrandt eBakker

    2012-12-01

    Full Text Available The CoCoMac database contains the results of published axonal tract-tracing studies in the macaque brain. The combined data are used to construct the macaque macro-connectome. We discuss the redevelopment of CoCoMac and compare it to six connectome-related projects: two resources that provide online access to raw tracing data in rodents, a connectome viewer for advanced 3d graphics, a partial but highly detailed rat connectome, a brain data management system that generates custom connectivity matrices, and a software package that covers the complete pipeline from connectivity data to large scale brain simulations.The 2nd edition of CoCoMac features many enhancements over the original. For example, a search wizard is provided for full access to all tables. Connectivity matrices are computed on demand in a user selected nomenclature. An online data entry system is available as a preview, and is to become a generic solution for community-driven manual data entry.We end with the question whether tract-tracing will remain the gold standard to uncover the wiring of brains, thereby mentioning developments in human connectome construction, tracer substances, polarized light imaging and serial block face scanning electron microscopy.

  6. CoCoMac 2.0 and the future of tract-tracing databases.

    Science.gov (United States)

    Bakker, Rembrandt; Wachtler, Thomas; Diesmann, Markus

    2012-01-01

    The CoCoMac database contains the results of several hundred published axonal tract-tracing studies in the macaque monkey brain. The combined results are used for constructing the macaque macro-connectome. Here we discuss the redevelopment of CoCoMac and compare it to six connectome-related projects: two online resources that provide full access to raw tracing data in rodents, a connectome viewer for advanced 3D graphics, a partial but highly detailed rat connectome, a brain data management system that generates custom connectivity matrices, and a software package that covers the complete pipeline from connectivity data to large-scale brain simulations. The second edition of CoCoMac features many enhancements over the original. For example, a search wizard is provided for full access to all tables and their nested dependencies. Connectivity matrices can be computed on demand in a user-selected nomenclature. A new data entry system is available as a preview, and is to become a generic solution for community-driven data entry in manually collated databases. We conclude with the question whether neuronal tracing will remain the gold standard to uncover the wiring of brains, thereby highlighting developments in human connectome construction, tracer substances, polarized light imaging, and serial block-face scanning electron microscopy.

  7. The MacGyver effect: alive and well in health services research?

    Directory of Open Access Journals (Sweden)

    Moriarty Helen J

    2011-09-01

    Full Text Available Abstract Background In a manner similar to the television action hero MacGyver, health services researchers need to respond to the pressure of unpredictable demands and constrained time frames. The results are often both innovative and functional, with the creation of outputs that could not have been anticipated in the initial planning and design of the research. Discussion In the conduct of health services research many challenges to robust research processes are generated as a result of the interface between academic research, health policy and implementation agendas. Within a complex and rapidly evolving environment the task of the health services researcher is, therefore, to juggle sometimes contradictory pressures to produce valid results. Summary This paper identifies the MacGyver-type dilemmas which arise in health services research, wherein innovation may be called for, to maintain the intended scientific method and rigour. These 'MacGyver drivers' are framed as opposing issues from the perspective of both academic and public policy communities. The ideas expressed in this paper are illustrated by four examples from research projects positioned at the interface between public policy strategy and academia.

  8. IDMA-Based MAC Protocol for Satellite Networks with Consideration on Channel Quality

    Directory of Open Access Journals (Sweden)

    Gongliang Liu

    2014-01-01

    Full Text Available In order to overcome the shortcomings of existing medium access control (MAC protocols based on TDMA or CDMA in satellite networks, interleave division multiple access (IDMA technique is introduced into satellite communication networks. Therefore, a novel wide-band IDMA MAC protocol based on channel quality is proposed in this paper, consisting of a dynamic power allocation algorithm, a rate adaptation algorithm, and a call admission control (CAC scheme. Firstly, the power allocation algorithm combining the technique of IDMA SINR-evolution and channel quality prediction is developed to guarantee high power efficiency even in terrible channel conditions. Secondly, the effective rate adaptation algorithm, based on accurate channel information per timeslot and by the means of rate degradation, can be realized. What is more, based on channel quality prediction, the CAC scheme, combining the new power allocation algorithm, rate scheduling, and buffering strategies together, is proposed for the emerging IDMA systems, which can support a variety of traffic types, and offering quality of service (QoS requirements corresponding to different priority levels. Simulation results show that the new wide-band IDMA MAC protocol can make accurate estimation of available resource considering the effect of multiuser detection (MUD and QoS requirements of multimedia traffic, leading to low outage probability as well as high overall system throughput.

  9. A Selective-Awakening MAC Protocol for Energy-Efficient Data Forwarding in Linear Sensor Networks

    Directory of Open Access Journals (Sweden)

    Iclia Villordo-Jimenez

    2018-01-01

    Full Text Available We introduce the Selective-Awakening MAC (SA-MAC protocol which is a synchronized duty-cycled protocol with pipelined scheduling for Linear Sensor Networks (LSNs. In the proposed protocol, nodes selectively awake depending on node density and traffic load conditions and on the state of the buffers of the receiving nodes. In order to characterize the performance of the proposed protocol, we present a Discrete-Time Markov Chain-based analysis that is validated through extensive discrete-event simulations. Our results show that SA-MAC significantly outperforms previous proposals in terms of energy consumption, throughput, and packet loss probability. This is particularly true under high node density and high traffic load conditions, which are expected to be common scenarios in the context of IoT applications. We also present an analysis by grade (i.e., the number of hops to the sink, which is located at one end of the LSN that reveals that LSNs exhibit heterogeneous performance depending on the nodes’ grade. Such results can be used as a design guideline for future LSN implementations.

  10. PaleoMac: A Macintosh™ application for treating paleomagnetic data and making plate reconstructions

    Science.gov (United States)

    Cogné, J. P.

    2003-01-01

    This brief note provides an overview of a new Macintosh™ application, PaleoMac, (MacOS 8.0 or later, 15Mb RAM required) which permits rapid processing of paleomagnetic data, from the demagnetization data acquired in the laboratory, to the treatment of paleomagnetic poles, plate reconstructions, finite rotation computations on a sphere, and characterization of relative plate motions. Capabilities of PaleoMac include (1) high interactivity between the user and data displayed on screen which provides a fast and easy way to handle, add and remove data or contours, perform computations on subsets of points, change projections, sizes, etc.; (2) performance of all standard principal component analysis and statistical processing on a sphere [, 1953] etc.); (3) output of high quality plots, compatible with graphic programs such as Adobe Illustrator, and output of numerical results as ASCII files. Beyond its usefulness in treating paleomagnetic data, its ability to handle plate motion computations should be of large interest to the Earth science community.

  11. Strategies for Optimal MAC Parameters Tuning in IEEE 802.15.6 Wearable Wireless Sensor Networks.

    Science.gov (United States)

    Alam, Muhammad Mahtab; Ben Hamida, Elyes

    2015-09-01

    Wireless body area networks (WBAN) has penetrated immensely in revolutionizing the classical heath-care system. Recently, number of WBAN applications has emerged which introduce potential limits to existing solutions. In particular, IEEE 802.15.6 standard has provided great flexibility, provisions and capabilities to deal emerging applications. In this paper, we investigate the application-specific throughput analysis by fine-tuning the physical (PHY) and medium access control (MAC) parameters of the IEEE 802.15.6 standard. Based on PHY characterizations in narrow band, at the MAC layer, carrier sense multiple access collision avoidance (CSMA/CA) and scheduled access protocols are extensively analyzed. It is concluded that, IEEE 802.15.6 standard can satisfy most of the WBANs applications throughput requirements by maximum achieving 680 Kbps. However, those emerging applications which require high quality audio or video transmissions, standard is not able to meet their constraints. Moreover, delay, energy efficiency and successful packet reception are considered as key performance metrics for comparing the MAC protocols. CSMA/CA protocol provides the best results to meet the delay constraints of medical and non-medical WBAN applications. Whereas, the scheduled access approach, performs very well both in energy efficiency and packet reception ratio.

  12. Performance Analysis of a Cluster-Based MAC Protocol for Wireless Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Jesús Alonso-Zárate

    2010-01-01

    Full Text Available An analytical model to evaluate the non-saturated performance of the Distributed Queuing Medium Access Control Protocol for Ad Hoc Networks (DQMANs in single-hop networks is presented in this paper. DQMAN is comprised of a spontaneous, temporary, and dynamic clustering mechanism integrated with a near-optimum distributed queuing Medium Access Control (MAC protocol. Clustering is executed in a distributed manner using a mechanism inspired by the Distributed Coordination Function (DCF of the IEEE 802.11. Once a station seizes the channel, it becomes the temporary clusterhead of a spontaneous cluster and it coordinates the peer-to-peer communications between the clustermembers. Within each cluster, a near-optimum distributed queuing MAC protocol is executed. The theoretical performance analysis of DQMAN in single-hop networks under non-saturation conditions is presented in this paper. The approach integrates the analysis of the clustering mechanism into the MAC layer model. Up to the knowledge of the authors, this approach is novel in the literature. In addition, the performance of an ad hoc network using DQMAN is compared to that obtained when using the DCF of the IEEE 802.11, as a benchmark reference.

  13. An Enhanced Reservation-Based MAC Protocol for IEEE 802.15.4 Networks

    Science.gov (United States)

    Afonso, José A.; Silva, Helder D.; Macedo, Pedro; Rocha, Luis A.

    2011-01-01

    The IEEE 802.15.4 Medium Access Control (MAC) protocol is an enabling standard for wireless sensor networks. In order to support applications requiring dedicated bandwidth or bounded delay, it provides a reservation-based scheme named Guaranteed Time Slot (GTS). However, the GTS scheme presents some drawbacks, such as inefficient bandwidth utilization and support to a maximum of only seven devices. This paper presents eLPRT (enhanced Low Power Real Time), a new reservation-based MAC protocol that introduces several performance enhancing features in comparison to the GTS scheme. This MAC protocol builds on top of LPRT (Low Power Real Time) and includes various mechanisms designed to increase data transmission reliability against channel errors, improve bandwidth utilization and increase the number of supported devices. A motion capture system based on inertial and magnetic sensors has been used to validate the protocol. The effectiveness of the performance enhancements introduced by each of the new features is demonstrated through the provision of both simulation and experimental results. PMID:22163826

  14. Intelligent Local Avoided Collision (iLAC) MAC Protocol for Very High Speed Wireless Network

    Science.gov (United States)

    Hieu, Dinh Chi; Masuda, Akeo; Rabarijaona, Verotiana Hanitriniala; Shimamoto, Shigeru

    Future wireless communication systems aim at very high data rates. As the medium access control (MAC) protocol plays the central role in determining the overall performance of the wireless system, designing a suitable MAC protocol is critical to fully exploit the benefit of high speed transmission that the physical layer (PHY) offers. In the latest 802.11n standard [2], the problem of long overhead has been addressed adequately but the issue of excessive colliding transmissions, especially in congested situation, remains untouched. The procedure of setting the backoff value is the heart of the 802.11 distributed coordination function (DCF) to avoid collision in which each station makes its own decision on how to avoid collision in the next transmission. However, collision avoidance is a problem that can not be solved by a single station. In this paper, we introduce a new MAC protocol called Intelligent Local Avoided Collision (iLAC) that redefines individual rationality in choosing the backoff counter value to avoid a colliding transmission. The distinguishing feature of iLAC is that it fundamentally changes this decision making process from collision avoidance to collaborative collision prevention. As a result, stations can avoid colliding transmissions with much greater precision. Analytical solution confirms the validity of this proposal and simulation results show that the proposed algorithm outperforms the conventional algorithms by a large margin.

  15. CoCoMac 2.0 and the future of tract-tracing databases

    Science.gov (United States)

    Bakker, Rembrandt; Wachtler, Thomas; Diesmann, Markus

    2012-01-01

    The CoCoMac database contains the results of several hundred published axonal tract-tracing studies in the macaque monkey brain. The combined results are used for constructing the macaque macro-connectome. Here we discuss the redevelopment of CoCoMac and compare it to six connectome-related projects: two online resources that provide full access to raw tracing data in rodents, a connectome viewer for advanced 3D graphics, a partial but highly detailed rat connectome, a brain data management system that generates custom connectivity matrices, and a software package that covers the complete pipeline from connectivity data to large-scale brain simulations. The second edition of CoCoMac features many enhancements over the original. For example, a search wizard is provided for full access to all tables and their nested dependencies. Connectivity matrices can be computed on demand in a user-selected nomenclature. A new data entry system is available as a preview, and is to become a generic solution for community-driven data entry in manually collated databases. We conclude with the question whether neuronal tracing will remain the gold standard to uncover the wiring of brains, thereby highlighting developments in human connectome construction, tracer substances, polarized light imaging, and serial block-face scanning electron microscopy. PMID:23293600

  16. Detection of Legionella, L. pneumophila and Mycobacterium Avium Complex (MAC) along Potable Water Distribution Pipelines

    Science.gov (United States)

    Whiley, Harriet; Keegan, Alexandra; Fallowfield, Howard; Bentham, Richard

    2014-01-01

    Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the other chloramine disinfection. Samples were collected four times over the year to provide seasonal variation and the chlorine or chloramine residual was measured during collection. Legionella spp., L. pneumophila and MAC were detected in both distribution systems throughout the year and were all detected at a maximum concentration of 103 copies/mL in the chlorine disinfected system and 106, 103 and 104 copies/mL respectively in the chloramine disinfected system. The concentrations of these opportunistic pathogens were primarily controlled throughout the distribution network through the maintenance of disinfection residuals. At a dead-end and when the disinfection residual was not maintained significant (p < 0.05) increases in concentration were observed when compared to the concentration measured closest to the processing plant in the same pipeline and sampling period. Total coliforms were not present in any water sample collected. This study demonstrates the ability of Legionella spp., L. pneumophila and MAC to survive the potable water disinfection process and highlights the need for greater measures to control these organisms along the distribution pipeline and at point of use. PMID:25046636

  17. Detection of Spoofed MAC Addresses in 802.11 Wireless Networks

    Science.gov (United States)

    Tao, Kai; Li, Jing; Sampalli, Srinivas

    Medium Access Control (MAC) address spoofing is considered as an important first step in a hacker's attempt to launch a variety of attacks on 802.11 wireless networks. Unfortunately, MAC address spoofing is hard to detect. Most current spoofing detection systems mainly use the sequence number (SN) tracking technique, which has drawbacks. Firstly, it may lead to an increase in the number of false positives. Secondly, such techniques cannot be used in systems with wireless cards that do not follow standard 802.11 sequence number patterns. Thirdly, attackers can forge sequence numbers, thereby causing the attacks to go undetected. We present a new architecture called WISE GUARD (Wireless Security Guard) for detection of MAC address spoofing on 802.11 wireless LANs. It integrates three detection techniques - SN tracking, Operating System (OS) fingerprinting & tracking and Received Signal Strength (RSS) fingerprinting & tracking. It also includes the fingerprinting of Access Point (AP) parameters as an extension to the OS fingerprinting for detection of AP address spoofing. We have implemented WISE GUARD on a test bed using off-the-shelf wireless devices and open source drivers. Experimental results show that the new design enhances the detection effectiveness and reduces the number of false positives in comparison with current approaches.

  18. Cross Layer PHY-MAC Protocol for Wireless Static and Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Chris Blondia

    2008-11-01

    Full Text Available Multihop mobile wireless networks have drawn a lot of attention in recent years thanks to their wide applicability in civil and military environments. Since the existing IEEE 802.11 distributed coordination function (DCF standard does not provide satisfactory access to the wireless medium in multihop mobile networks, we have designed a cross-layer protocol, (CroSs-layer noise aware power driven MAC (SNAPdMac, which consists of two parts. The protocol first concentrates on the flexible adjustment of the upper and lower bounds of the contention window (CW to lower the number of collisions. In addition, it uses a power control scheme, triggered by the medium access control (MAC layer, to limit the waste of energy and also to decrease the number of collisions. Thanks to a noticeable energy conservation and decrease of the number of collisions, it prolongs significantly the lifetime of the network and delays the death of the first node while increasing both the throughput performance and the sending bit rate/throughput fairness among contending flows.

  19. Magnetically assisted chemical separation (MACS) process: Preparation and optimization of particles for removal of transuranic elements

    International Nuclear Information System (INIS)

    Nunez, L.; Kaminski, M.; Bradley, C.; Buchholz, B.A.; Aase, S.B.; Tuazon, H.E.; Vandegrift, G.F.; Landsberger, S.

    1995-05-01

    The Magnetically Assisted Chemical Separation (MACS) process combines the selectivity afforded by solvent extractants with magnetic separation by using specially coated magnetic particles to provide a more efficient chemical separation of transuranic (TRU) elements, other radionuclides, and heavy metals from waste streams. Development of the MACS process uses chemical and physical techniques to elucidate the properties of particle coatings and the extent of radiolytic and chemical damage to the particles, and to optimize the stages of loading, extraction, and particle regeneration. This report describes the development of a separation process for TRU elements from various high-level waste streams. Polymer-coated ferromagnetic particles with an adsorbed layer of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) diluted with tributyl phosphate (TBP) were evaluated for use in the separation and recovery of americium and plutonium from nuclear waste solutions. Due to their chemical nature, these extractants selectively complex americium and plutonium contaminants onto the particles, which can then be recovered from the solution by using a magnet. The partition coefficients were larger than those expected based on liquid[liquid extractions, and the extraction proceeded with rapid kinetics. Extractants were stripped from the particles with alcohols and 400-fold volume reductions were achieved. Particles were more sensitive to acid hydrolysis than to radiolysis. Overall, the optimization of a suitable NMCS particle for TRU separation was achieved under simulant conditions, and a MACS unit is currently being designed for an in-lab demonstration

  20. Detection of Legionella, L. pneumophila and Mycobacterium avium complex (MAC) along potable water distribution pipelines.

    Science.gov (United States)

    Whiley, Harriet; Keegan, Alexandra; Fallowfield, Howard; Bentham, Richard

    2014-07-18

    Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the other chloramine disinfection. Samples were collected four times over the year to provide seasonal variation and the chlorine or chloramine residual was measured during collection. Legionella spp., L. pneumophila and MAC were detected in both distribution systems throughout the year and were all detected at a maximum concentration of 103 copies/mL in the chlorine disinfected system and 106, 103 and 104 copies/mL respectively in the chloramine disinfected system. The concentrations of these opportunistic pathogens were primarily controlled throughout the distribution network through the maintenance of disinfection residuals. At a dead-end and when the disinfection residual was not maintained significant (p pipeline and sampling period. Total coliforms were not present in any water sample collected. This study demonstrates the ability of Legionella spp., L. pneumophila and MAC to survive the potable water disinfection process and highlights the need for greater measures to control these organisms along the distribution pipeline and at point of use.

  1. Heroic Measures for an American Hero: Attempting to Save the Life of General Douglas MacArthur.

    Science.gov (United States)

    Pappas, Theodore N

    2017-12-01

    General Douglas MacArthur was a towering public figure on an international stage for the first half of the 20th century. He was healthy throughout his life but developed a series of medical problems when he entered his 80s. This article reviews the General's medical care during two separate life-threatening medical crises that required surgical intervention. The first episode occurred in 1960 when MacArthur presented with renal failure due to an obstructed prostate. Four years later after his 84th birthday, MacArthur developed bile duct obstruction from common duct stones. He underwent an uncomplicated cholecystectomy and common duct exploration but developed variceal bleeding requiring an emergent splenorenal shunt. His terminal event was precipitated by strangulated bowel in long-ignored very large inguinal hernias. MacArthur died, despite state-of-the-art surgical intervention, due to renal failure and hepatic coma.

  2. Deformation, Failure, and Fatigue Life of SiC/Ti-15-3 Laminates Accurately Predicted by MAC/GMC

    Science.gov (United States)

    Bednarcyk, Brett A.; Arnold, Steven M.

    2002-01-01

    NASA Glenn Research Center's Micromechanics Analysis Code with Generalized Method of Cells (MAC/GMC) (ref.1) has been extended to enable fully coupled macro-micro deformation, failure, and fatigue life predictions for advanced metal matrix, ceramic matrix, and polymer matrix composites. Because of the multiaxial nature of the code's underlying micromechanics model, GMC--which allows the incorporation of complex local inelastic constitutive models--MAC/GMC finds its most important application in metal matrix composites, like the SiC/Ti-15-3 composite examined here. Furthermore, since GMC predicts the microscale fields within each constituent of the composite material, submodels for local effects such as fiber breakage, interfacial debonding, and matrix fatigue damage can and have been built into MAC/GMC. The present application of MAC/GMC highlights the combination of these features, which has enabled the accurate modeling of the deformation, failure, and life of titanium matrix composites.

  3. Current evidence for the use of C-MAC videolaryngoscope in adult airway management: a review of the literature

    Directory of Open Access Journals (Sweden)

    Xue FS

    2017-07-01

    Full Text Available Fu-Shan Xue, Hui-Xian Li, Ya-Yang Liu, Gui-Zhen Yang Department of Anesthesiology, Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People’s Republic of China Abstract: The C-MAC videolaryngoscope is the first Macintosh-typed videolaryngoscope. Since the advent of its original version video Macintosh system in 1999, this device has been modified several times. A unique feature of C-MAC device is its ability to provide the 2 options of direct and video laryngoscopy with the same device. The available evidence shows that in patients with normal airways, C-MAC videolaryngoscope compared with direct laryngoscopy can provide comparable or better laryngeal views and exerts less force on maxillary incisors, but does not offer conclusive benefits with regard to intubation time, intubation success, number of intubation attempts, the use of adjuncts, and hemodynamic responses to intubation. In patients with predicted or known difficult airways, C-MAC videolaryngoscope can achieve a better laryngeal view, a higher intubation success rate and a shorter intubation time than direct laryngoscopy. Furthermore, the option to perform direct and video laryngoscopy with the same device makes C-MAC videolaryngoscope exceptionally useful for emergency intubation. In addition, the C-MAC videolaryngoscope is a very good tool for tracheal intubation teaching. However, tracheal intubation with C-MAC videolaryngoscope may occasionally fail and introduction of C-MAC videolaryngoscope in clinical practice must be accompanied by formal training programs in normal and difficult airway managements. Keywords: videolaryngoscopy, direct laryngoscopy, airway management, tracheal intubation, patient safety

  4. An Energy-Efficient MAC Protocol Using Dynamic Queue Management for Delay-Tolerant Mobile Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yugui Qu

    2011-02-01

    Full Text Available Conventional MAC protocols for wireless sensor network perform poorly when faced with a delay-tolerant mobile network environment. Characterized by a highly dynamic and sparse topology, poor network connectivity as well as data delay-tolerance, delay-tolerant mobile sensor networks exacerbate the severe power constraints and memory limitations of nodes. This paper proposes an energy-efficient MAC protocol using dynamic queue management (EQ-MAC for power saving and data queue management. Via data transfers initiated by the target sink and the use of a dynamic queue management strategy based on priority, EQ-MAC effectively avoids untargeted transfers, increases the chance of successful data transmission, and makes useful data reach the target terminal in a timely manner. Experimental results show that EQ-MAC has high energy efficiency in comparison with a conventional MAC protocol. It also achieves a 46% decrease in packet drop probability, 79% increase in system throughput, and 25% decrease in mean packet delay.

  5. TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role in monocyte adhesion to vascular endothelium.

    Directory of Open Access Journals (Sweden)

    Seung Jin Lee

    Full Text Available Toll-like receptor 4 (TLR4 is known to mediate monocyte adhesion to endothelial cells, however, its role on the expression of monocyte adhesion molecules is unclear. In the present study, we investigated the role of TLR4 on the expression of monocyte adhesion molecules, and determined the functional role of TLR4-induced adhesion molecules on monocyte adhesion to endothelial cells. When THP-1 monocytes were stimulated with Kdo2-Lipid A (KLA, a specific TLR4 agonist, Mac-1 expression was markedly increased in association with an increased adhesion of monocytes to endothelial cells. These were attenuated by anti-Mac-1 antibody, suggesting a functional role of TLR4-induced Mac-1 on monocyte adhesion to endothelial cells. In monocytes treated with MK886, a 5-lipoxygenase (LO inhibitor, both Mac-1 expression and monocyte adhesion to endothelial cells induced by KLA were markedly attenuated. Moreover, KLA increased the expression of mRNA and protein of 5-LO, suggesting a pivotal role of 5-LO on these processes. In in vivo studies, KLA increased monocyte adhesion to aortic endothelium of wild-type (WT mice, which was attenuated in WT mice treated with anti-Mac-1 antibody as well as in TLR4-deficient mice. Taken together, TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role on monocyte adhesion to vascular endothelium, leading to increased foam cell formation in the development of atherosclerosis.

  6. La République de Macédoine dans la presse française

    Directory of Open Access Journals (Sweden)

    Toni Glamcevski

    2011-12-01

    Full Text Available Les médias français s'intéressent à la République de Macédoine quand la Grèce refuse de la reconnaître, mais souvent adoptent des positions progrecques.Malgré son nom illustre, la Macédoine est un pays très mal connu en France. Jusqu’en 1991, très peu de gens connaissaient l’existence de la République de Macédoine. Les médias français commencent à s’intéresser au pays lors du blocus de sa reconnaissance par la Grèce (1991. De nombreux articles, commentaires, interviews tentent alors d’éclaircir la situation du pays, mais il y a eu très peu d’interventions de la part des intellectuels et « experts ». Cette communication montre les grandes lignes des articles parus en France dans la période entre 1991 et 2009. Mais la presse française, en assimilant le peuple macédonien au terme « Slaves », voulait sans doute pendant le conflit du Kosovo et le conflit de 2001, éclaircir la situation, mais l’utilisation de ce terme est aussi comprise comme une tentative de négation de l’existence du peuple macédonien. Le nom de la République de Macédoine bloque le pays dans son passé, c'est aux Macédoniens de définir leur identité, pas à leurs voisins ni aux membres de l'UE.In spite of its famous name, Macedonia is not well-known in France. Till 1991, very few persons even knew the existence of a Republic of Macedonia. The French Medias began to get interested in it with the Greek blocus of Macedonia. A lot of papers, comments, interviews tried then to explain the main lines of the country's situation but with a very light participation of experts or intellectuals. One can find in this paper the main lines of the French press on Macedonia from spring 1999 to September 2001. The French papers, as a whole, assimilating the “Macedonian” people to “Slaves”, perhaps to make a clear difference when explaining the situation during the Kossovo crisis or later, during the crisis inside Macedonia, contributed

  7. Mac-1 (CD11b/CD18) is essential for Fc receptor-mediated neutrophil cytotoxicity and immunologic synapse formation.

    Science.gov (United States)

    van Spriel, A B; Leusen, J H; van Egmond, M; Dijkman, H B; Assmann, K J; Mayadas, T N; van de Winkel, J G

    2001-04-15

    Receptors for human immunoglobulin (Ig)G and IgA initiate potent cytolysis of antibody (Ab)-coated targets by polymorphonuclear leukocytes (PMNs). Mac-1 (complement receptor type 3, CD11b/CD18) has previously been implicated in receptor cooperation with Fc receptors (FcRs). The role of Mac-1 in FcR-mediated lysis of tumor cells was characterized by studying normal human PMNs, Mac-1-deficient mouse PMNs, and mouse PMNs transgenic for human FcR. All PMNs efficiently phagocytosed Ab-coated particles. However, antibody-dependent cellular cytotoxicity (ADCC) was abrogated in Mac-1(-/-) PMNs and in human PMNs blocked with anti-Mac-1 monoclonal Ab (mAb). Mac-1(-/-) PMNs were unable to spread on Ab-opsonized target cells and other Ab-coated surfaces. Confocal laser scanning and electron microscopy revealed a striking difference in immunologic synapse formation between Mac-1(-/-) and wild-type PMNs. Also, respiratory burst activity could be measured outside membrane-enclosed compartments by using Mac-1(-/-) PMNs bound to Ab-coated tumor cells, in contrast to wild-type PMNs. In summary, these data document an absolute requirement of Mac-1 for FcR-mediated PMN cytotoxicity toward tumor targets. Mac-1(-/-) PMNs exhibit defective spreading on Ab-coated targets, impaired formation of immunologic synapses, and absent tumor cytolysis.

  8. Climate change, land use and land surveyors

    OpenAIRE

    van der Molen, P.; Mitchell, D.

    2016-01-01

    Research reveals that the land sector is a major emitter of greenhouse gases. But the land sector has also potential to reduce emissions. Different from other emission sectors like energy and transport, the land sector (in particular the rural area including forests) has the potential to also remove greenhouse gases from the atmosphere through sequestration and storage. This requires land use, land use change and forestry to be managed with respect to climate change goals. Carbon storage has ...

  9. MacMS: A Mass Spectrometer Simulator: Abstract of Issue 9906M

    Science.gov (United States)

    Bigger, Stephen W.; Craig, Robert A.

    1999-10-01

    MacMS is a program for Mac-OS compatible computers that simulates a magnetic sector mass spectrometer (1-4) designed to operate in the mass-to-charge (m/z) ratio range of 1-200 amu. MacMS has two operational modules. The first module (see Figure 1) is called the "Path" module and enables the user to quantitatively examine the trajectory of an ion of given m/z ratio in the electric and magnetic fields of the simulated "instrument". By systematically measuring a series of trajectories of different ions under different electric and magnetic field conditions, the user can determine how the resolution of the "instrument" is affected by these experimentally variable parameters. The user can thus choose suitable instrumental conditions for scanning a given m/z ratio range with good separation between the peaks. The second module (see Figure 2) is called as the "Spectrometer" module and enables the user to record, under any chosen instrumental conditions, the mass spectrum of (i) the instrumental background, (ii) neon, (iii) methane, or (iv) the parent ion of carbon tetrachloride. Both voltage scanning and magnetic scanning are possible (5). A hard copy of any mass spectrum that has been recorded can also be obtained. MacMS can read ASCII data files containing mass spectral information of compounds other than those that are "built-in" to the simulator. The appropriate format for creating such data files is described in the program documentation. There are a number of instructional exercises that can be conducted using the mass spectral information contained within the simulator. These are included in the program documentation. For example, the intensities of the 20Ne+, 21Ne+, and 22Ne+ species can be determined from hard copies of mass spectra of neon that are obtained under different instrumental sensitivities. The relative abundances of the three isotopes of neon can thus be calculated and compared with the literature values (6). The simulator also includes adjustable

  10. Application of the MacCormack scheme to overland flow routing for high-spatial resolution distributed hydrological model

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Liang, Xu; Xu, Yi; Hernández, Felipe; Li, Lianxia

    2018-03-01

    Although process-based distributed hydrological models (PDHMs) are evolving rapidly over the last few decades, their extensive applications are still challenged by the computational expenses. This study attempted, for the first time, to apply the numerically efficient MacCormack algorithm to overland flow routing in a representative high-spatial resolution PDHM, i.e., the distributed hydrology-soil-vegetation model (DHSVM), in order to improve its computational efficiency. The analytical verification indicates that both the semi and full versions of the MacCormack schemes exhibit robust numerical stability and are more computationally efficient than the conventional explicit linear scheme. The full-version outperforms the semi-version in terms of simulation accuracy when a same time step is adopted. The semi-MacCormack scheme was implemented into DHSVM (version 3.1.2) to solve the kinematic wave equations for overland flow routing. The performance and practicality of the enhanced DHSVM-MacCormack model was assessed by performing two groups of modeling experiments in the Mercer Creek watershed, a small urban catchment near Bellevue, Washington. The experiments show that DHSVM-MacCormack can considerably improve the computational efficiency without compromising the simulation accuracy of the original DHSVM model. More specifically, with the same computational environment and model settings, the computational time required by DHSVM-MacCormack can be reduced to several dozen minutes for a simulation period of three months (in contrast with one day and a half by the original DHSVM model) without noticeable sacrifice of the accuracy. The MacCormack scheme proves to be applicable to overland flow routing in DHSVM, which implies that it can be coupled into other PHDMs for watershed routing to either significantly improve their computational efficiency or to make the kinematic wave routing for high resolution modeling computational feasible.

  11. National study of microphthalmia, anophthalmia, and coloboma (MAC) in Scotland: investigation of genetic aetiology

    Science.gov (United States)

    Morrison, D; FitzPatrick, D; Hanson, I; Williamson, K; van Heyningen, V; Fleck, B; Jones, I; Chalmers, J; Campbell, H

    2002-01-01

    We report an epidemiological and genetic study attempting complete ascertainment of subjects with microphthalmia, anophthalmia, and coloboma (MAC) born in Scotland during a 16 year period beginning on 1 January 1981. A total of 198 cases were confirmed giving a minimum live birth prevalence of 19 per 100 000. One hundred and twenty-two MAC cases (61.6%) from 115 different families were clinically examined and detailed pregnancy, medical, and family histories obtained. A simple, rational, and apparently robust classification of the eye phenotype was developed based on the presence or absence of a defect in closure of the optic (choroidal) fissure. A total of 85/122 (69.7%) of cases had optic fissure closure defects (OFCD), 12/122 (9.8%) had non-OFCD, and 25/122 (20.5%) had defects that were unclassifiable owing to the severity of the corneal or anterior chamber abnormality. Segregation analysis assuming single and multiple incomplete ascertainment, respectively, returned a sib recurrence risk of 6% and 10% in the whole group and 8.1% and 13.3% in the OFCD subgroup. Significant recurrence risks were found in both unilateral and bilateral disease. In four families, one parent had an OFCD, two of which were new diagnoses in asymptomatic subjects. All recurrences in first degree relatives occurred in the OFCD group with a single first cousin recurrence seen in the non-OFCD group. A total of 84/122 of the MAC cases were screened for mutations in the coding regions of PAX6, CHX10, and SIX3. No pathogenic mutations were identified in the OFCD cases. A single PAX6 homeodomain missense mutation was identified in a subject with partial aniridia that had been initially misclassified as coloboma. PMID:11826019

  12. Determination of the optimal stylet strategy for the C-MAC videolaryngoscope.

    LENUS (Irish Health Repository)

    McElwain, J

    2010-04-01

    The C-MAC videolaryngoscope is a novel intubation device that incorporates a camera system at the end of its blade, thereby facilitating obtaining a view of the glottis without alignment of the oral, pharyngeal and tracheal axes. It retains the traditional Macintosh blade shape and can be used as a direct or indirect laryngoscope. We wished to determine the optimal stylet strategy for use with the C-MAC. Ten anaesthetists were allowed up to three attempts to intubate the trachea in one easy and three progressively more difficult laryngoscopy scenarios in a SimMan manikin with four tracheal tube stylet strategies: no stylet; stylet; directional stylet (Parker Flex-It); and hockey-stick stylet. The use of a stylet conferred no advantage in the easy laryngoscopy scenario. In the difficult scenarios, the directional and hockey-stick stylets performed best. In the most difficult scenario, the median (IQR [range]) duration of the successful intubation attempt was lowest with the hockey-stick stylet; 18 s (15-22 [12-43]) s, highest with the unstyletted tracheal tube; 60 s (60-60 [60, 60]) s and styletted tracheal tube 60 s (29-60 [18-60]) s, and intermediate with the directional stylet 21 s (15-60 [8-60]) s. The use of a stylet alone does not confer benefit in the setting of easy laryngoscopy. However, in more difficult laryngoscopy scenarios, the C-MAC videolaryngoscope performs best when used with a stylet that angulates the distal tracheal tube. The hockey-stick stylet configuration performed best in the scenarios tested.

  13. Estimation of Physiological Cost Index as an Energy Expenditure Index using MacGregor’s Equation

    Directory of Open Access Journals (Sweden)

    Binaya SJB Rana

    2015-09-01

    Full Text Available Introduction: Physical activity and energy expenditure can be quantified by measuring heart rate, oxygen uptake and respiratory quotient. The Physiological Cost Index (PCI proposed by MacGregor is a simple and straightforward method to estimate the energy expenditure index. Here, we aim to estimate the energy expenditure among young Asian population using MacGregor’s equation. Methods: A total of 50 young randomly selected healthy females performed 50m, 100m and 150m walking test at their self-selected preferred speed. The physiological cost index values for 100 m walk at speeds slower and faster than the preferred speed were also obtained. The physiological cost index during exercise was calculated using MacGregor’s equation considering heart rate and speed of walking over the varying distances. Results: The PCI values on three different distances are consistent during self selected preferred speed. The PCI estimation on second and third tests for all three distances walked consistently reproducible. However for each distance walked, the first test the PCI was significantly higher than the second and third test values. The PCI values increased significantly when subjects walked either slower (p = 0.02 or faster (p = 0.001 than their normal preferred speed. Conclusion: The physiological cost index values were similar for varying distances walks. The PCI was the least at the preferred speed of walking and increased when the subjects either walked slower or faster than the preferred speed. The first estimation was higher than subsequent estimations. Keywords: energy expenditure index; exercise; physiological cost index. | PubMed

  14. Quiebra de Fannie Mae y Freddie Mac desde la experiencia latinoamericana

    Directory of Open Access Journals (Sweden)

    Wesley Marshall

    2008-09-01

    Full Text Available Conforme al deterioro de la posición financiera de los bancos semi públicos, Fannie Mae y Freddie Mac, durante los últimos meses, el debate sobre su viabilidad actual y su futuro en el sistema financiero estadounidense se ha intensificado. Si bien el debate ha abarcado diversas posiciones dentro de círculos financieros y académicos, en los Estados Unidos, no se han tomado en cuenta las experiencias históricas de la banca pública latinoamericana durante la crisis financiera, y que al parecer ambas compartan muchos elementos con la dinámica que está detrás del debate actual sobre Fannie Mae and Freddie Mac. En América Latina, tales momentos han ofrecido la oportunidad para transferir activos financieros del sector privado de decreciente valor a la banca pública, y también para la reducción drástica de la actividad de la banca pública, permitiendo así la expansión de actores del sector privado a costa de la banca pública. Tales experiencias son de relevancia particular al futuro de Fannie Mae and Freddie Mac, dado que los mismos grupos que gestionaron estas crisis son los mismos que actualmente están administrando la crisis financiera de los Estados Unidos. Como se argumentará, las mismas estrategias usadas en América Latina para minimizar el papel del Estado en el sector financiero actualmente están siendo empleadas en los Estados Unidos.

  15. Adaptive MAC-layer protocol for multiservice digital access via tree and branch communication networks

    Science.gov (United States)

    Sriram, Kotikalapudi; Li, Chia-Chang; Magill, Peter; Whitaker, Norman A.; Dail, James E.; Dajer, Miguel A.; Siller, Curtis A.

    1995-11-01

    Described here is an adaptive MAC-layer protocol that supports multiservice (STM and ATM) applications in the context of subscriber access to tree and branch (e.g., fiber-coaxial cable) networks. The protocol adapts to changing demands for a mix of circuit and cell mode applications, and efficiently allocates upstream and downstream bandwidth to a variety of bursty and isochronous traffic sources. In the case of a hybrid fiber-coaxial (HFC) network the protocol resides in customer premises equipment and a common head-end controller. A medium-access control (MAC) processor provides for dividing the time domain for a given digital bitstream into successive frames, each with multiple STM and ATM time slots. Within the STM region of a frame, variable length time slots are allocated to calls (e.g., telephony, video telephony) requiring different amounts of bandwidth. A contention access signaling channel is also provided in this region for call control and set-up requests. Within the ATM region fixed-length time slots accommodate one individual ATM cell. These ATM time slots may be reserved for a user for the duration of a call or burst of successive ATM cells, or shared via a contention process. At least one contention time slot is available for signaling messages related to ATM call control and set-up requests. Further, the fixed-length ATM time slots may be reserved by a user for the duration of a call, or shared through a contention process. This paper describes the MAC-layer protocol, its relation to circuit- and ATM- amenable applications, and its performance with respect to signaling throughput and latency, and bandwidth efficiency for several service scenarios.

  16. La question macédonienne pendant la guerre civile grecque

    Directory of Open Access Journals (Sweden)

    Christina Alexopoulos

    2012-05-01

    Full Text Available Le traitement de la question macédonienne durant la guerre civile grecque interroge la mémoire du conflit entre oubli, déni et instrumentalisation politique. Le Parti communiste grec essaya de concilier la politique nationale avec la géopolitique internationale, en tenant compte des revendications macédoniennes et de la stratégie de Tito. L’engagement des Macédoniens slavophones de Grèce à la résistance communiste et à la guerre civile exprima une lutte identitaire et sociale. La propagande gouvernementale transforma la question macédonienne en « preuve suprême » d’une   trahison nationale » des communistes devant « le danger slave » et occulta le collaborationnisme dont les milices nationalistes se rendirent coupables. Malgré la démocratisation du pays et le travail de l’historiographie contemporaine, le traitement actuel de la question dans les discours politiques et journalistiques montre la vivacité du nationalisme d’antan au sein de la société civile.Treating the Macedonian question during Greek civil war means dealing with the memory of the conflict, somewhere between oblivion, denial and political instrumentation. The Greek Communist Party tried to reconcile national politics with international geopolitics in its consideration of the Macedonian demands and Tito’s strategy. On the other hand the engagement of slavophone Macedonians of Greece, in the communist resistance and the civil war, expressed a social struggle and an identity conflict. The governmental propaganda transformed the Macedonian question into the “ultimate proof” of the communists committing “national treason” with regard to the “Slavic danger” and did its best to hide the collaborationism, of which, the nationalist militia was guilty of. Despite the return of Democracy in the country, the way the question is actually being treated in politics and by the media is revelatory of the nationalism reigning in the past and still

  17. Towards a simple characterization of the Chern-Schwartz-MacPherson class

    OpenAIRE

    Fullwood, James; Wang, Dongxu

    2016-01-01

    For a large class of possibly singular complete intersections we prove a formula for their Chern-Schwartz-MacPherson classes in terms of a single blowup along a scheme supported on the singular loci of such varieties. In the hypersurface case our formula recovers a formula of Aluffi proven in 1996. As our formula is in no way tailored to the complete intersection hypothesis, we conjecture that it holds for all closed subschemes of a smooth variety. If in fact true, such a formula would provid...

  18. Dependence and Vulnerability in the moral philosophy of Alasdair MacIntyre

    Directory of Open Access Journals (Sweden)

    Javier de la Torre Díaz

    2017-10-01

    Full Text Available We are all dependent persons and from this limitation and human condition we can find some deep insights to better understand vulnerability as a principle of bioethics. This article introduces the concept of dependence as outlined by the Scottish philosopher, settled in the United States since 1971, Alasdair MacIntyre in his work Dependent Rational Animals. From this work, we want to rehabilitate the importance of dependency in the life of every living being and we want to propose some basic ideas so as to gain a better understanding of the principle of vulnerability.

  19. Dove sta andando l'analisi musicale? Riflessioni sul VII EuroMac

    Directory of Open Access Journals (Sweden)

    Mario Baroni

    2014-01-01

    Full Text Available Come tutti i lettori della Rivista ormai sapranno, si è svolto a Roma dal 29 settembre al 2 ottobre di quest’anno, presso il Conservatorio di S. Cecilia, il settimo convegno europeo di analisi musicale (VII European Music Analysis Conference ossia VII EuroMac. Nel convegno, organizzato dal GATM e diretto da Giorgio Sanguinetti, sono state presentate 197 relazioni e svolti otto laboratori. Tutti i materiali sono stati riassunti in un volume (Programme and Abstract Book, Iter Edizioni di Subiaco curato da Egidio Pozzi e Antonio Cascelli.

  20. The Making Assessment Count (MAC consortium maximising assessment and feedback design by working together

    Directory of Open Access Journals (Sweden)

    Mark JP Kerrigan

    2011-02-01

    Full Text Available The Making Assessment Count (MAC project started at the University of Westminster in 2008. It sought to align staff and student expectations of feedback and support greater use of feed-forward approaches. A baseline analysis of staff views in the School of Life Sciences suggested that students did not make strategic use of the feedback they received. A similar analysis of the student position revealed that as a group they felt that the feedback provided to them was often insufficiently helpful. To address this dichotomy, a MAC process was developed in the School of Life Sciences and trialled with a cohort of about 350 first year undergraduate students. The process was based on a student-centred, three-stage model of feedback: Subject specific, Operational, and Strategic (SOS model. The student uses the subject tutor's feedback on an assignment to complete an online self-review questionnaire delivered by a simple tool. The student answers are processed by a web application called e-Reflect to generate a further feedback report. Contained within this report are personalised graphical representations of performance, time management, satisfaction and other operational feedback designed to help the student reflect on their approach to preparation and completion of future work. The student then writes in an online learning journal, which is shared with their personal tutor to support the personal tutorial process and the student's own development plan (PDP. Since the initial development and implementation of the MAC process within Life Sciences at Westminster, a consortium of universities has worked together to maximise the benefits of the project outcomes and collaboratively explore how the SOS model and e-Reflect can be exploited in different institutional and subject contexts. This paper presents and discusses an evaluation of the use of the MAC process within Life Sciences at Westminster from both staff and student perspective. In addition, the

  1. MAC-Level Communication Time Modeling and Analysis for Real-Time WSNs

    Directory of Open Access Journals (Sweden)

    STANGACIU, V.

    2016-02-01

    Full Text Available Low-level communication protocols and their timing behavior are essential to developing wireless sensor networks (WSNs able to provide the support and operating guarantees required by many current real-time applications. Nevertheless, this aspect still remains an issue in the state-of-the-art. In this paper we provide a detailed analysis of a recently proposed MAC-level communication timing model and demonstrate its usability in designing real-time protocols. The results of a large set of measurements are also presented and discussed here, in direct relation to the main time parameters of the analyzed model.

  2. Lightweight MAC-Spoof Detection Exploiting Received Signal Power and Median Filtering

    DEFF Research Database (Denmark)

    Papini, Davide

    2011-01-01

    this kind of attack based on signal power monitoring. The main contribution of our work is the introduction of a median l- ter that enables the detection of the attack by looking at the variance of the signal power. We take into account two types of references for the samples, time and number of frames......IEEE 802.11 networks are subject to MAC-spoof attacks. An attacker can easily steal the identity of a legitimate station, even Access Points, thus enabling him to take full control over network basic mech- anisms or even access restricted resources. In this paper we propose a method to detect...

  3. Performance analysis for a QoS-aware hybrid token-CDMA MAC protocol

    CSIR Research Space (South Africa)

    Liu, YS

    2007-09-01

    Full Text Available ) 20000 Bad state duration ( i badτ ) 3.2 ms Bad state ibadPEP 1.0 Good state igoodPEP Holtzman’s approximation WTRP Channel bit rate 1.28 Mbps Signal to Noise Rato (SNR) 8 dB .... INTRODUCTION d hoc and wireless mesh networks (WMNs) [1] are commonly known to implement IEEE 802.11 related schemes as their medium access control (MAC) protocols. It is known from [2,3] that with the 802.11 based scheme; the performance is degraded...

  4. A Camac-VME-MacIntosh data acquisition system for nuclear experiments

    International Nuclear Information System (INIS)

    Anzalone, A.; Giustolisi, F.

    1989-01-01

    A multiprocessor system for data acquisition and analysis in low energy nuclear physics has been realized at the Laboratorio Nazionale del Sud. the system is built around Camac, VME-bus and MacIntosh PC. A multiprocessor software has been developed, using RTF, Macsys and Cern cross-software. The execution of several programs which run on several VME-CPU's and on an external PC, is coordinated by a mail box protocol. No operating system is used on the VME-CPU's

  5. The Big Mac Index 21 Years On: An Evaluation of Burgereconomics

    OpenAIRE

    Kenneth W. Clements; Yihui Lan; Shi Pei Seah

    2007-01-01

    The Big Mac Index, introduced by The Economist magazine 21 years ago, claims to provide the “true value” of a large number of currencies. This paper assesses the economic value of this index. We show that (i) the index suffers from a substantial bias; (ii) once the bias is allowed for, the index tracks exchange rates reasonably well over the medium to longer term in accordance with relative purchasing power parity theory; (iii) the index is at least as good as the industry standard, the rando...

  6. SBMAC: Smart Blocking MAC Mechanism for Variable UW-ASN (Underwater Acoustic Sensor Network Environment

    Directory of Open Access Journals (Sweden)

    Soo-Hyun Park

    2010-01-01

    Full Text Available In this paper, several MAC scheduling methods applicable to an underwater environment are proposed. Besides, a new marine communication system model was proposed to improve the reliability of the proposed SBMAC method. The scheme minimizes transmission of control frames except for data transmission and various transmission methods and ACK methods can be used together. Simulation models are set indices and analysis of the underwater environment is established to conduct reliable simulations. Consequently, the performance improvement of the proposed method is verified with respect to delay time, data transmission rate, memory utilization, energy efficiency, etc.

  7. Swyer- James -MacLeod syndrome presenting as hemoptysis in an adult

    Directory of Open Access Journals (Sweden)

    Santosh Kumar

    2012-01-01

    Full Text Available Swyer-James/MacLeod syndrome is an uncommon disease with characteristic radiological feature of unilateral hyperlucency due to loss of pulmonary vasculature and air trapping. Typically, this disorder is diagnosed in childhood during evaluations for recurrent respiratory infections. Here, we report a case in a 30-year-old adult female who presented with dyspnoea, cough with expectoration and recurrent hemoptysis due to associated bronchiectasis. This case highlights the importance of computed tomography in the diagnostic workup of recurrent hemoptysis in pulmonary tuberculosis epidemic countries like India

  8. 7 years of MacGyver sessions at EGU and AGU: what happened?

    Science.gov (United States)

    Hut, Rolf; Selker, John; Weijs, Steven; Luxemburg, Wim; Wickert, Andy; Blume, Theresa; Bamburger, Jan; Stoof, Cathelijne; Tauro, Flavia

    2016-04-01

    The session that this poster is in, the: "Self-made sensors and unintended use of measurement equipment", also known as the "MacGyver-session" has had 7 years of scientists contributing their self made devices, hacks and solutions with the hydrological community. In 2009, the first session was held at the AGU fall meeting and since 2011 a session is also organised at the EGU General Assembly. On this poster, and in the accompanying review paper, we will present an overview of the work presented in the last 7 years, cataloging the work of the inventive scientists who have contributed to these successful, and above all: fun, sessions.

  9. Mini-mac - escala de ajustamento mental para o câncer: estrutura fatorial Mini-mac - the mental adjustment to cancer scale: factorial structure

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Gandini

    2008-03-01

    Full Text Available Trata-se de estudo da estrutura fatorial da escala Mini-MAC, que mede o ajustamento mental dos pacientes ao câncer. Após análise semântica, a escala foi aplicada em 283 pacientes de um hospital universitário com diferentes tipos e estádios da doença que possuíam idade média de 54 anos. Confirmada a fatorabilidade da amostra (KMO = 0,88, os dados foram submetidos à análise dos componentes principais, rotação oblíqua, dada a interdependência entre os fatores. Foram mantidos sete fatores com valores próprios maiores que 1,0. Apenas dois fatores possuíam índices de fidedignidade satisfatórios ("Preocupação Ansiógena" com "Alpha de Cronbach" de 0,87 e "Desamparo/Desesperança" com "Alpha" de 0,74, reunindo 13 itens com cargas fatoriais maiores ou iguais a 0,40 e explicavam 30% da variância total. Os resultados revelaram a boa qualidade psicométrica do instrumento. As diferenças entre a estrutura fatorial do instrumento original e a deste estudo podem ser atribuídas às diferenças culturais e educacionais entre as amostras.Se trata de estudio de la estructura factorial de la escala Mini-MAC, que mide el ajuste mental de los pacientes al cáncer. Tras el análisis semántico, la escala fue aplicada en 283 pacientes de un hospital universitario con distintos tipos y estadios de la enfermedad - pacientes esos, que poseían edad media de 54 años. Confirmada la factorabilidad de la muestra (KMO = 0,88, los datos fueron sometidos al análisis de los componentes principales, rotación oblicua, dada a la interdependencia entre los factores. Fueron mantenidos siete factores con valores propios mayores que 1,0. Sólo dos factores poseían índices de fidedignidad satisfactorios ("Preocupación Ansiogénica" con "Alpha de Cronbach" de 0,87 y "Desamparo/Desesperanza" con "Alpha" de 0,74, reuniendo 13 ítemes con cargas factoriales mayores o iguales a 0,40 y explicaban 30% de la varianza total. Los resultados revelaron la buena calidad

  10. GSR-TDMA: A Geometric Spatial Reuse-Time Division Multiple Access MAC Protocol for Multihop Underwater Acoustic Sensor Networks

    Directory of Open Access Journals (Sweden)

    Changho Yun

    2016-01-01

    Full Text Available The nonnegligible propagation delay of acoustic signals causes spatiotemporal uncertainty that occasionally enables simultaneous, collision-free packet transmission among underwater nodes (UNs. These transmissions can be handled by efficiently managing the channel access of the UNs in the data-link layer. To this end, Geometric Spatial Reuse-TDMA (GSR-TDMA, a new TDMA-based MAC protocol, is designed for use in centralized, multihop underwater acoustic sensor networks (UASNs, and in this case all UNs are periodically scheduled after determining a geometric map according to the information on their location. The scheduling strategy increases the number of UNs that send packets coincidentally via two subscheduling configurations (i.e., interhop and intrahop scheduling. Extensive simulations are used to investigate the reception success rate (RSR and the multihop delay (MHD of GSR-TDMA, and the results are compared to those of previous approaches, including C-MAC and HSR-TDMA. GSR-TDMA outperforms C-MAC; the RSR of GSR-TDMA is 15% higher than that of C-MAC, and the MHD of GSR-TDMA is 30% lower than that of C-MAC at the most. In addition, GSR-TDMA provides even better performance improvements over HSR-TDMA; the RSR of GSR-TDMA is 50% higher than that of HSR-TDMA, and the MHD of GSR-TDMA is an order of 102 lower than that of HSR-TDMA at the most.

  11. MacCormack's technique-based pressure reconstruction approach for PIV data in compressible flows with shocks

    Science.gov (United States)

    Liu, Shun; Xu, Jinglei; Yu, Kaikai

    2017-06-01

    This paper proposes an improved approach for extraction of pressure fields from velocity data, such as obtained by particle image velocimetry (PIV), especially for steady compressible flows with strong shocks. The principle of this approach is derived from Navier-Stokes equations, assuming adiabatic condition and neglecting viscosity of flow field boundaries measured by PIV. The computing method is based on MacCormack's technique in computational fluid dynamics. Thus, this approach is called the MacCormack method. Moreover, the MacCormack method is compared with several approaches proposed in previous literature, including the isentropic method, the spatial integration and the Poisson method. The effects of velocity error level and PIV spatial resolution on these approaches are also quantified by using artificial velocity data containing shock waves. The results demonstrate that the MacCormack method has higher reconstruction accuracy than other approaches, and its advantages become more remarkable with shock strengthening. Furthermore, the performance of the MacCormack method is also validated by using synthetic PIV images with an oblique shock wave, confirming the feasibility and advantage of this approach in real PIV experiments. This work is highly significant for the studies on aerospace engineering, especially the outer flow fields of supersonic aircraft and the internal flow fields of ramjets.

  12. A feedback-retransmission based asynchronous frequency hopping MAC protocol for military aeronautical ad hoc networks

    Directory of Open Access Journals (Sweden)

    Jinhui TANG

    2018-05-01

    Full Text Available Attacking time-sensitive targets has rigid demands for the timeliness and reliability of information transmission, while typical Media Access Control (MAC designed for this application works well only in very light-load scenarios; as a consequence, the performances of system throughput and channel utilization are degraded. For this problem, a feedback-retransmission based asynchronous FRequency hopping Media Access (FRMA control protocol is proposed. Burst communication, asynchronous Frequency Hopping (FH, channel coding, and feedback retransmission are utilized in FRMA. With the mechanism of asynchronous FH, immediate packet transmission and multi-packet reception can be realized, and thus the timeliness is improved. Furthermore, reliability can be achieved via channel coding and feedback retransmission. With theories of queuing theory, Markov model, packets collision model, and discrete Laplace transformation, the formulas of packet success probability, system throughput, average packet end-to-end delay, and delay distribution are obtained. The approximation accuracy of theoretical derivation is verified by experimental results. Within a light-load network, the proposed FRMA has the ability of millisecond delay and 99% reliability as well as outperforms the non-feedback-retransmission based asynchronous frequency hopping media access control protocol. Keywords: Ad hoc networks, Aeronautical communications, Frequency hopping, Media Access Control (MAC, Time-sensitive

  13. The use of the MacCormack scheme in computational hydraulics

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, R. [Universidad Central de Venezuela, Inst. de Mecanica de Fluidos, Caracas (Venezuela); Zhang, H.; Kahawita, R. [Ecole Polytechnique, Dept. of Civil Engineering, Montreal, Quebec (Canada)

    1985-07-01

    This manuscript describes the development of a numerical model that solves shallow water problems based upon an enhanced version of the MacCormack explicit scheme (MS). The MS has been successfully applied to solve numerous problems in gas dynamics. However, the standard application of the MS to solve the shallow water equations can cause in certain test cases non-linear instabilities and non-symmetrical results that eventually destroy the solution. By examining the calculation 'cell' one can show that the MS is not symmetric in space, which explains why it cannot be used directly in the treatment of hydraulic problems most of which possess irregular boundaries thereby resulting in a flow with no 'preferred direction'. This is contrary to what is usually encountered in aerodynamics. The enhanced MacCormack scheme is obtained by a simple modification to the original formulation resulting in a symmetric scheme. The scheme has been applied to the computation of the flowfield in a real life situation with satisfactory results. (author)

  14. The use of the MacCormack scheme in computational hydraulics

    International Nuclear Information System (INIS)

    Garcia, R.; Zhang, H.; Kahawita, R.

    1985-01-01

    This manuscript describes the development of a numerical model that solves shallow water problems based upon an enhanced version of the MacCormack explicit scheme (MS). The MS has been successfully applied to solve numerous problems in gas dynamics. However, the standard application of the MS to solve the shallow water equations can cause in certain test cases non-linear instabilities and non-symmetrical results that eventually destroy the solution. By examining the calculation 'cell' one can show that the MS is not symmetric in space, which explains why it cannot be used directly in the treatment of hydraulic problems most of which possess irregular boundaries thereby resulting in a flow with no 'preferred direction'. This is contrary to what is usually encountered in aerodynamics. The enhanced MacCormack scheme is obtained by a simple modification to the original formulation resulting in a symmetric scheme. The scheme has been applied to the computation of the flowfield in a real life situation with satisfactory results. (author)

  15. A Service Differentiated MAC Protocol for OFDM/TDMA Wireless Systems

    Institute of Scientific and Technical Information of China (English)

    WANG Ying; ZHANG Ping

    2005-01-01

    This paper proposes a Service Differentiated-Dynamic Slotted Multiple Access (SD-DSMA) protocol with QoS guarantee. The Media Access Control (MAC) frame format is variable according to the traffic of uplink and downlink and the traffic of control and data. In addition, the services are divided into two categories, Guaranteed Bandwidth (GB) and Best Effort (BE). Uplink control message slots are designed for the GB users to reduce contention. Taking into consideration the techniques in physical layer, a two-Dimensional Radio Resource Allocation (2-D RRA) method is proposed. The 2-D RRA is an efficient way to allocate radio resources for multi-cell, multi-user OFDM/TDMA system as it takes into consideration both the channel condition and the co-channel interference. The piggyback mechanism and fair scheduling algorithm are adopted for GB services, and the max C/I scheduling algorithm is used for BE services. The simulation results show that the proposed MAC protocol has better performance in terms of delay, probability of successful access request.

  16. Low Duty-Cycling MAC Protocol for Low Data-Rate Medical Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Chongqing Zhang

    2017-05-01

    Full Text Available Wireless body area networks (WBANs are severely energy constrained, and how to improve the energy efficiency so as to prolong the network lifetime as long as possible is one of the most important goals of WBAN research. Low data-rate WBANs are promising to cut down the energy consumption and extend the network lifetime. Considering the characteristics and demands of low data-rate WBANs, a low duty-cycling medium access control (MAC protocol is specially designed for this kind of WBAN in this paper. Longer superframes are exploited to cut down the energy consumed on the transmissions and receptions of redundant beacon frames. Insertion time slots are embedded into the inactive part of a superframe to deliver the frames and satisfy the quality of service (QoS requirements. The number of the data subsections in an insertion time slot can be adaptively adjusted so as to accommodate low data-rate WBANs with different traffic. Simulation results show that the proposed MAC protocol performs well under the condition of low data-rate monitoring traffic.

  17. MAC-Layer Active Dropping for Real-Time Video Streaming in 4G Access Networks

    KAUST Repository

    She, James

    2010-12-01

    This paper introduces a MAC-layer active dropping scheme to achieve effective resource utilization, which can satisfy the application-layer delay for real-time video streaming in time division multiple access based 4G broadband wireless access networks. When a video frame is not likely to be reconstructed within the application-layer delay bound at a receiver for the minimum decoding requirement, the MAC-layer protocol data units of such video frame will be proactively dropped before the transmission. An analytical model is developed to evaluate how confident a video frame can be delivered within its application-layer delay bound by jointly considering the effects of time-varying wireless channel, minimum decoding requirement of each video frame, data retransmission, and playback buffer. Extensive simulations with video traces are conducted to prove the effectiveness of the proposed scheme. When compared to conventional cross-layer schemes using prioritized-transmission/retransmission, the proposed scheme is practically implementable for more effective resource utilization, avoiding delay propagation, and achieving better video qualities under certain conditions.

  18. Performance Analysis of Modified Accelerative Preallocation MAC Protocol for Passive Star-Coupled WDMA Networks

    Science.gov (United States)

    Yun, Changho; Kim, Kiseon

    2006-04-01

    For the passive star-coupled wavelength-division multiple-access (WDMA) network, a modified accelerative preallocation WDMA (MAP-WDMA) media access control (MAC) protocol is proposed, which is based on AP-WDMA. To show the advantages of MAP-WDMA as an adequate MAC protocol for the network over AP-WDMA, the channel utilization, the channel-access delay, and the latency of MAP-WDMA are investigated and compared with those of AP-WDMA under various data traffic patterns, including uniform, quasi-uniform type, disconnected type, mesh type, and ring type data traffics, as well as the assumption that a given number of network stations is equal to that of channels, in other words, without channel sharing. As a result, the channel utilization of MAP-WDMA can be competitive with respect to that of AP-WDMA at the expense of insignificantly higher latency. Namely, if the number of network stations is small, MAP-WDMA provides better channel utilization for uniform, quasi-uniform-type, and disconnected-type data traffics at all data traffic loads, as well as for mesh and ring-type data traffics at low data traffic loads. Otherwise, MAP-WDMA only outperforms AP-WDMA for the first three data traffics at higher data traffic loads. In the aspect of channel-access delay, MAP-WDMA gives better performance than AP-WDMA, regardless of data traffic patterns and the number of network stations.

  19. The rise of empirical research in medical ethics: a MacIntyrean critique and proposal.

    Science.gov (United States)

    Lawrence, Ryan E; Curlin, Farr A

    2011-04-01

    Hume's is/ought distinction has long limited the role of empirical research in ethics, saying that data about what something is cannot yield conclusions about the way things ought to be. However, interest in empirical research in ethics has been growing despite this countervailing principle. We attribute some of this increased interest to a conceptual breakdown of the is/ought distinction. MacIntyre, in reviewing the history of the is/ought distinction, argues that is and ought are not strictly separate realms but exist in a close relationship that is clarified by adopting a teleological orientation. We propose that, instead of recovering a teleological orientation, society tends to generate its own goals via democratic methods like those described by Rousseau or adopt agnosticism about teleology such as described by Richard Rorty. In both latter scenarios, the distinction between is and ought is obscured, and the role for empirical research grows, but for controversial reasons. MacIntyre warns that the is/ought distinction should remain, but reminds ethicists to make careful arguments about when and why it is legitimate to move from is to ought.

  20. Stochastic generation of MAC waves and implications for convection in Earth's core

    Science.gov (United States)

    Buffett, Bruce; Knezek, Nicholas

    2018-03-01

    Convection in Earth's core can sustain magnetic-Archemedes-Coriolis (MAC) waves through a variety of mechanisms. Buoyancy and Lorentz forces are viable sources for wave motion, together with the effects of magnetic induction. We develop a quantitative description for zonal MAC waves and assess the source mechanisms using a numerical dynamo model. The largest sources at conditions accessible to the dynamo model are due to buoyancy forces and magnetic induction. However, when these sources are extrapolated to conditions expected in Earth's core, the Lorentz force emerges as the dominant generation mechanism. This source is expected to produce wave velocities of roughly 2 km yr-1 when the internal magnetic field is characterized by a dimensionless Elsasser number of roughly Λ ≈ 10 and the root-mean-square convective velocity defines a magnetic Reynolds number of Rm ≈ 103. Our preferred model has a radially varying stratification and a constant (radial) background magnetic field. It predicts a broad power spectrum for the wave velocity with most power distributed across periods from 30 to 100 yr.

  1. Noncooperative 802.11 MAC Layer Fingerprinting and Tracking of Mobile Devices

    Directory of Open Access Journals (Sweden)

    Pieter Robyns

    2017-01-01

    Full Text Available We present two novel noncooperative MAC layer fingerprinting and tracking techniques for Wi-Fi (802.11 enabled mobile devices. Our first technique demonstrates how a per-bit entropy analysis of a single captured frame allows an adversary to construct a fingerprint of the transmitter that is 80.0 to 67.6 percent unique for 50 to 100 observed devices and 33.0 to 15.1 percent unique for 1,000 to 10,000 observed devices. We show how existing mitigation strategies such as MAC address randomization can be circumvented using only this fingerprint and temporal information. Our second technique leverages peer-to-peer 802.11u Generic Advertisement Service (GAS requests and 802.11e Block Acknowledgement (BA requests to instigate transmissions on demand from devices that support these protocols. We validate these techniques using two datasets, one of which was recorded at a music festival containing 28,048 unique devices and the other at our research lab containing 138 unique devices. Finally, we discuss a number of countermeasures that can be put in place by mobile device vendors in order to prevent noncooperative tracking through the discussed techniques.

  2. Intra Cluster Light properties in the CLASH-VLT cluster MACS J1206.2-0847

    CERN Document Server

    Presotto, V; Nonino, M; Mercurio, A; Grillo, C; Rosati, P; Biviano, A; Annunziatella, M; Balestra, I; Cui, W; Sartoris, B; Lemze, D; Ascaso, B; Moustakas, J; Ford, H; Fritz, A; Czoske, O; Ettori, S; Kuchner, U; Lombardi, M; Maier, C; Medezinski, E; Molino, A; Scodeggio, M; Strazzullo, V; Tozzi, P; Ziegler, B; Bartelmann, M; Benitez, N; Bradley, L; Brescia, M; Broadhurst, T; Coe, D; Donahue, M; Gobat, R; Graves, G; Kelson, D; Koekemoer, A; Melchior, P; Meneghetti, M; Merten, J; Moustakas, L; Munari, E; Postman, M; Regős, E; Seitz, S; Umetsu, K; Zheng, W; Zitrin, A

    2014-01-01

    We aim at constraining the assembly history of clusters by studying the intra cluster light (ICL) properties, estimating its contribution to the fraction of baryons in stars, f*, and understanding possible systematics/bias using different ICL detection techniques. We developed an automated method, GALtoICL, based on the software GALAPAGOS to obtain a refined version of typical BCG+ICL maps. We applied this method to our test case MACS J1206.2-0847, a massive cluster located at z=0.44, that is part of the CLASH sample. Using deep multi-band SUBARU images, we extracted the surface brightness (SB) profile of the BCG+ICL and we studied the ICL morphology, color, and contribution to f* out to R500. We repeated the same analysis using a different definition of the ICL, SBlimit method, i.e. a SB cut-off level, to compare the results. The most peculiar feature of the ICL in MACS1206 is its asymmetric radial distribution, with an excess in the SE direction and extending towards the 2nd brightest cluster galaxy which i...

  3. Land Cover - Minnesota Land Cover Classification System

    Data.gov (United States)

    Minnesota Department of Natural Resources — Land cover data set based on the Minnesota Land Cover Classification System (MLCCS) coding scheme. This data was produced using a combination of aerial photograph...

  4. Climate change, land use and land surveyors

    NARCIS (Netherlands)

    van der Molen, P.; Mitchell, D.

    2016-01-01

    Research reveals that the land sector is a major emitter of greenhouse gases. But the land sector has also potential to reduce emissions. Different from other emission sectors like energy and transport, the land sector (in particular the rural area including forests) has the potential to also remove

  5. A hybrid MAC protocol design for energy-efficient very-high-throughput millimeter wave, wireless sensor communication networks

    Science.gov (United States)

    Jian, Wei; Estevez, Claudio; Chowdhury, Arshad; Jia, Zhensheng; Wang, Jianxin; Yu, Jianguo; Chang, Gee-Kung

    2010-12-01

    This paper presents an energy-efficient Medium Access Control (MAC) protocol for very-high-throughput millimeter-wave (mm-wave) wireless sensor communication networks (VHT-MSCNs) based on hybrid multiple access techniques of frequency division multiplexing access (FDMA) and time division multiplexing access (TDMA). An energy-efficient Superframe for wireless sensor communication network employing directional mm-wave wireless access technologies is proposed for systems that require very high throughput, such as high definition video signals, for sensing, processing, transmitting, and actuating functions. Energy consumption modeling for each network element and comparisons among various multi-access technologies in term of power and MAC layer operations are investigated for evaluating the energy-efficient improvement of proposed MAC protocol.

  6. Latency-Optimized and Energy-Efficient MAC Protocol for Underwater Acoustic Sensor Networks: A Cross-Layer Approach

    Directory of Open Access Journals (Sweden)

    Cheng Xiuzhen

    2010-01-01

    Full Text Available Considering the energy constraint for fixed sensor nodes and the unacceptable long propagation delay, especially for latency sensitive applications of underwater acoustic sensor networks, we propose a MAC protocol that is latency-optimized and energy-efficient scheme and combines the physical layer and the MAC layer to shorten transmission delay. On physical layer, we apply convolution coding and interleaver for transmitted information. Moreover, dynamic code rate is exploited at the receiver side to accelerate data reception rate. On MAC layer, unfixed frame length scheme is applied to reduce transmission delay, and to ensure the data successful transmission rate at the same time. Furthermore, we propose a network topology: an underwater acoustic sensor network with mobile agent. Through fully utilizing the supper capabilities on computation and mobility of autonomous underwater vehicles, the energy consumption for fixed sensor nodes can be extremely reduced, so that the lifetime of networks is extended.

  7. Morphological variation and taxonomic interpretation in the moss genus Bryum in Antarctica

    OpenAIRE

    Seppelt,Rodney D.; Kanda,Hiroshi

    1986-01-01

    The potential for morphological variation in Antarctic species of Bryum is evaluated and related to problems associated with taxonomic interpretation based on specimens from the Soya Coast, Mac. Robertson Coast, Vestfold Hills and Knox Coast. B. argenteum HEDW. Has been positively determined for Continental Antarctica from six localities on the Soya Coast and from Ross Island, southern Victoria Land. Specimens from the Vestfold Hills and Knox Coast considered with some reservation as this spe...

  8. +Psychometric evaluation of the MacDQoL individualised measure of the impact of macular degeneration on quality of life

    Directory of Open Access Journals (Sweden)

    ffytche Timothy

    2005-04-01

    Full Text Available Abstract Background The MacDQoL is an individualised measure of the impact of macular degeneration (MD on quality of life (QoL. There is preliminary evidence of its psychometric properties and sensitivity to severity of MD. The aim of this study was to carry out further psychometric evaluation with a larger sample and investigate the measure's sensitivity to MD severity. Methods Patients with MD (n = 156: 99 women, 57 men, mean age 79 ± 13 years, recruited from eye clinics (one NHS, one private completed the MacDQoL by telephone interview and later underwent a clinic vision assessment including near and distance visual acuity (VA, comfortable near VA, contrast sensitivity, colour recognition, recovery from glare and presence or absence of distortion or scotoma in the central 10° of the visual field. Results The completion rate for the MacDQoL items was 99.8%. Of the 26 items, three were dropped from the measure due to redundancy. A fourth was retained in the questionnaire but excluded when computing the scale score. Principal components analysis and Cronbach's alpha (0.944 supported combining the remaining 22 items in a single scale. Lower MacDQoL scores, indicating more negative impact of MD on QoL, were associated with poorer distance VA (better eye r = -0.431 p Conclusion The MacDQoL 22-item scale has excellent internal consistency reliability and a single-factor structure. The measure is acceptable to respondents and the generic QoL item, MD-specific QoL item and average weighted impact score are related to several measures of vision. The MacDQoL demonstrates that MD has considerable negative impact on many aspects of QoL, particularly independence, leisure activities, dealing with personal affairs and mobility. The measure may be valuable for use in clinical trials and routine clinical care.

  9. Potential of Wake-Up Radio-Based MAC Protocols for Implantable Body Sensor Networks (IBSN—A Survey

    Directory of Open Access Journals (Sweden)

    Vignesh Raja Karuppiah Ramachandran

    2016-11-01

    Full Text Available With the advent of nano-technology, medical sensors and devices are becoming highly miniaturized. Consequently, the number of sensors and medical devices being implanted to accurately monitor and diagnose a disease is increasing. By measuring the symptoms and controlling a medical device as close as possible to the source, these implantable devices are able to save lives. A wireless link between medical sensors and implantable medical devices is essential in the case of closed-loop medical devices, in which symptoms of the diseases are monitored by sensors that are not placed in close proximity of the therapeutic device. Medium Access Control (MAC is crucial to make it possible for several medical devices to communicate using a shared wireless medium in such a way that minimum delay, maximum throughput, and increased network life-time are guaranteed. To guarantee this Quality of Service (QoS, the MAC protocols control the main sources of limited resource wastage, namely the idle-listening, packet collisions, over-hearing, and packet loss. Traditional MAC protocols designed for body sensor networks are not directly applicable to Implantable Body Sensor Networks (IBSN because of the dynamic nature of the radio channel within the human body and the strict QoS requirements of IBSN applications. Although numerous MAC protocols are available in the literature, the majority of them are designed for Body Sensor Network (BSN and Wireless Sensor Network (WSN. To the best of our knowledge, there is so far no research paper that explores the impact of these MAC protocols specifically for IBSN. MAC protocols designed for implantable devices are still in their infancy and one of their most challenging objectives is to be ultra-low-power. One of the technological solutions to achieve this objective so is to integrate the concept of Wake-up radio (WuR into the MAC design. In this survey, we present a taxonomy of MAC protocols based on their use of Wu

  10. Low Latency MAC Protocol in Wireless Sensor Networks Using Timing Offset

    Science.gov (United States)

    Choi, Seung Sik

    This paper proposes a low latency MAC protocol that can be used in sensor networks. To extend the lifetime of sensor nodes, the conventional solution is to synchronize active/sleep periods of all sensor nodes. However, due to these synchronized sensor nodes, packets in the intermediate nodes must wait until the next node wakes up before it can forward a packet. This induces a large delay in sensor nodes. To solve this latency problem, a clustered sensor network which uses two types of sensor nodes and layered architecture is considered. Clustered heads in each cluster are synchronized with different timing offsets to reduce the sleep delay. Using this concept, the latency problem can be solved and more efficient power usage can be obtained.

  11. Upwind MacCormack Euler solver with non-equilibrium chemistry

    Science.gov (United States)

    Sherer, Scott E.; Scott, James N.

    1993-01-01

    A computer code, designated UMPIRE, is currently under development to solve the Euler equations in two dimensions with non-equilibrium chemistry. UMPIRE employs an explicit MacCormack algorithm with dissipation introduced via Roe's flux-difference split upwind method. The code also has the capability to employ a point-implicit methodology for flows where stiffness is introduced through the chemical source term. A technique consisting of diagonal sweeps across the computational domain from each corner is presented, which is used to reduce storage and execution requirements. Results depicting one dimensional shock tube flow for both calorically perfect gas and thermally perfect, dissociating nitrogen are presented to verify current capabilities of the program. Also, computational results from a chemical reactor vessel with no fluid dynamic effects are presented to check the chemistry capability and to verify the point implicit strategy.

  12. Fast Oblivious AES A Dedicated application of the MiniMac protocol

    DEFF Research Database (Denmark)

    Zakarias, Rasmus Winther; Damgård, Ivan Bjerre

    2015-01-01

    We present an actively secure multi-partycomputation of the Advanced Encryption Standard (AES). To the best of our knowledge it is the fastest of its kind to date. We start from an efficient actively secure evaluation of general binary circuits that was implemented by the authors of [DLT14......]. They presented an optimized implementation of the so-called MiniMac protocol [DZ13] that runs in the pre-processing model, and applied this to a binary AES circuit. In this paper we de- scribe how to dedicate the pre-processing to the structure of AES, which improves significantly the throughput and latency...... of previous actively secure implementations. We get a latency of about 6 ms and amortised time about 0.4 ms per AES block, which seems completely adequate for practical applications such as verification of 1-time passwords....

  13. Encuesta de parásitos intestinales en 615 escolares del Rímac

    Directory of Open Access Journals (Sweden)

    Luis Gonzales-Mugaburu

    1956-12-01

    Full Text Available El examen microscópico de una sola muestra de heces de cada uno de 615 escolares del Rímac, ha mostrado: 1. El elevado porcentaje de protozoarios intestinales encontrados, sugiere una alta contaminación fecal. 2. La alta frecuencia de H. nana 166 (27.0% constituye un problema al que hay que prestar atención. 3. El hallazgo de Strongyloides stercoralis y Ancylostoma o Necator sólo en sujetos que habían estado algún tiempo en la Selva del Perú, sugiere una vez más, que dichos parásitos no son transmitidos en esta parte de la Costa. 4. La presencia de tres casos de Isospora belli nos indica que esta coccidia es más frecuente de lo que se suponía.

  14. Bounds on absolutely maximally entangled states from shadow inequalities, and the quantum MacWilliams identity

    Science.gov (United States)

    Huber, Felix; Eltschka, Christopher; Siewert, Jens; Gühne, Otfried

    2018-04-01

    A pure multipartite quantum state is called absolutely maximally entangled (AME), if all reductions obtained by tracing out at least half of its parties are maximally mixed. Maximal entanglement is then present across every bipartition. The existence of such states is in many cases unclear. With the help of the weight enumerator machinery known from quantum error correction and the shadow inequalities, we obtain new bounds on the existence of AME states in dimensions larger than two. To complete the treatment on the weight enumerator machinery, the quantum MacWilliams identity is derived in the Bloch representation. Finally, we consider AME states whose subsystems have different local dimensions, and present an example for a 2×3×3×3 system that shows maximal entanglement across every bipartition.

  15. Altruistic Backoff: Collision Avoidance for Receiver-Initiated MAC Protocols for Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon; Orfanidis, Charalampos; Dragoni, Nicola

    2014-01-01

    In receiver-initiated medium access control (MAC) protocols for wireless sensor networks, communication is initiated by the receiver node which transmits beacons indicating its availability to receive data. In the case of multiple senders having traffic for a given receiver, such beacons form...... points where collisions are likely to happen. In this paper, we present altruistic backoff (AB), a novel collision avoidance mechanism that aims to avoid collisions before the transmission of a beacon. As a result of an early backoff, senders spend less time in idle listening waiting for a beacon, thus...... saving significant amounts of energy. We present an implementation of AB for Texas Instruments' eZ430-rf2500 sensor nodes and we evaluate its performance with simulations and experiments....

  16. El discurso funerario de Lucas Macías en Al filo del agua

    Directory of Open Access Journals (Sweden)

    Norma Esther García Meza

    2009-07-01

    Full Text Available En la provincia mexicana, los velorios y los enterramientos entretejen rituales y diversas prácticas, como el repaso detallado de las causas de la muerte y valoraciones sobre la vida del difunto, convirtiéndose en eventos de socialización donde el lenguaje tiene un lugar destacado. Animados por las bebidas propias de la región donde ocurren, los asistentes hablan del difunto, de sus deudos y discuten asuntos éticos y filosóficos asociados a la vida y la muerte. Uno de estos discursos es recreado artísticamente en la novela de Yáñez en la figura de Lucas Macías.

  17. Village in the Jungle: The Eighth Annual Doireann MacDermott Lecture

    Directory of Open Access Journals (Sweden)

    Baden Offord

    2011-03-01

    Full Text Available This paper is a slightly edited version of a keynote lecture, delivered at the Aula Magna of the University of Barcelona as The Eighth Annual Doireann MacDermott Lecture, organized by the university’s Australian Studies Centre in December 2007. Offord’s essay takes us from Leonard Woolf’s creative and ethical intervention in Britain’s colonial project, forged through a transformative vision of the ‘spirit of place’ in his novel The Village in the Jungle (1931, to the Australian specifics of colonialism and its aftermath. Highly critical of the dominant power structures in Australian society that keep sustaining the Enlightenment discourse of an unfinished colonial project, Offord delineates alternative strategies so as to deal with identity and belonging, arguing for a notion/nation of ‘cultural citizenship’, no longer based on exclusions.

  18. An Empirical Study and some Improvements of the MiniMac Protocol for Secure Computation

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Lauritsen, Rasmus; Toft, Tomas

    2014-01-01

    Recent developments in Multi-party Computation (MPC) has resulted in very efficient protocols for dishonest majority in the preprocessing model. In particular, two very promising protocols for Boolean circuits have been proposed by Nielsen et al. (nicknamed TinyOT) and by Damg˚ard and Zakarias...... suggest a modification of MiniMac that achieves increased parallelism at no extra communication cost. This gives an asymptotic improvement of the original protocol as well as an 8-fold speed-up of our implementation. We compare the resulting protocol to TinyOT for the case of secure computation in parallel...... of a large number of AES encryptions and find that it performs better than results reported so far on TinyOT, on the same hardware.p...

  19. Endospores of B subtilis are pyrogenic and activate Mono Mac 6 cells

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, Erik W; Christensen, Jens D

    2003-01-01

    interleukin-6. Lipopolysaccharides (LPS) dose-dependently induce interleukin-6 release, but the curve differs from that of LTA both in shape and offset. The interleukin-6 secretion induced by LPS, LTA and B. subtilis bacteria can be blocked by 73-85% by an antibody directed against CD14, whereas the antibody......The monocytic cell line Mono Mac 6 is sensitive to pyrogens and interleukin-6 secretion is induced after exposure to pyrogens. The aim of this study is to examine the pyrogenic activity and the interleukin-6-inducing capacity of the Gram-positive B. subtilis bacteria, endospores and isolated cell...... in a sandwich immunoassay. B. subtilis bacteria and endospores induce interleukin-6 in a dose-dependent manner. Endospores are less potent than bacteria. Lipoteichoic acid (LTA) isolated from B. subtilis induces interleukin-6 in a dose-dependent manner, whereas muramyl dipeptide (MDP) is unable to induce...

  20. ABNORMAL RETURN TRADING VOLUME ACTIVITY PADA PERISTIWA AMBRUKNYA FANNIE MAE DAN FREDDIE MAC

    Directory of Open Access Journals (Sweden)

    Dyah Ani Pangastuti

    2017-03-01

    Full Text Available The global economic crisis was a disaster for all nations in the world due to itsimpact once seemed to hamper the economy of a nation. This research studied the eventsthat would see if there was an effect of global economic crisis preceded by the U.S. Financialcrisis was triggered by the collapse of Fannie Mae and Freddie Mac in the property business(subprime mortgages on September 7th, 2008. This study used samples that had been pub-licly traded company listed on the Indonesia Stock Exchange and entered into the sequenceof LQ-45 in the year of 2008. Hypothesis testing used was t-test on the average abnormalreturn and average trading volume of activity. Test results for the average abnormal returnshowed there were no significant differences before and after the Subprime Mortgage. Thetest results for the average trading volume of activity indicated the presence of a significantdifference before and after the Subprime Mortgage.