910 research outputs found
To cap it all off, again:dynamic capping and recapping of coding and non-coding RNAs to control transcript fate and biological activity
Detecting and Studying Higgs Bosons at a Photon-Photon Collider
We examine the potential for detecting and studying Higgs bosons at a
photon-photon collider facility associated with a future linear collider. Our
study incorporates realistic \gam\gam luminosity spectra based on the most
probable available laser technology. Results include detector simulations. We
study the cases of: a) a SM-like Higgs boson; b) the heavy MSSM Higgs bosons;
c) a Higgs boson with no couplings from a general two Higgs doublet
model.Comment: 52 pages, 26 figures, revised version with new appendi
Accuracy and variability of acoustic measures of voicing onset
Five commonly used methods for determining the onset of voicing of syllable-initial stop consonants were compared. The speech and glottal activity of 16 native speakers of Cantonese with normal voice quality were investigated during the production of consonant vowel (CV) syllables in Cantonese. Syllables consisted of the initial consonants /ph/, /th/, /kh/, /p/, /t/, and /k/ followed by the vowel /a/. All syllables had a high level tone, and were all real words in Cantonese. Measurements of voicing onset were made based on the onset of periodicity in the acoustic waveform, and on spectrographic measures of the onset of a voicing bar (f0), the onset of the first formant (F1), second formant (F2), and third formant (F3). These measurements were then compared against the onset of glottal opening as determined by electroglottography. Both accuracy and variability of each measure were calculated. Results suggest that the presence of aspiration in a syllable decreased the accuracy and increased the variability of spectrogram-based measurements, but did not strongly affect measurements made from the acoustic waveform. Overall, the acoustic waveform provided the most accurate estimate of voicing onset; measurements made from the amplitude waveform were also the least variable of the five measures. These results can be explained as a consequence of differences in spectral tilt of the voicing source in breathy versus modal phonation. ©2003 Acoustical Society of America.published_or_final_versio
CP--violating Chargino Contributions to the Higgs Coupling to Photon Pairs in the Decoupling Regime of Higgs Sector
In most supersymmetric theories, charginos belong to
the class of the lightest supersymmetric particles and the couplings of Higgs
bosons to charginos are in general complex so that the CP--violating chargino
contributions to the loop--induced coupling of the lightest Higgs boson to
photon pairs can be sizable even in the decoupling limit of large pseudoscalar
mass with only the lightest Higgs boson kinematically accessible at
future high energy colliders. We introduce a specific benchmark scenario of CP
violation consistent with the electric dipole moment constraints and with a
commonly accepted baryogenesis mechanism in the minimal supersymmetric Standard
Model. Based on the benchmark scenario of CP violation, we demonstrate that the
fusion of the lightest Higgs boson in linearly polarized photon--photon
collisions can allow us to confirm the existence of the CP--violating chargino
contributions {\it even in the decoupling regime of the Higgs sector} for
nearly degenerate SU(2) gaugino and higgsino mass parameters of about the
electroweak scale.Comment: 1+13 pages, 3 eps figure
Sensory sociological phenomenology, somatic learning and 'lived' temperature in competitive pool swimming
In this article, we address an existing lacuna in the sociology of the senses, by employing sociological phenomenology to illuminate the under-researched sense of temperature, as lived by a social group for whom water temperature is particularly salient: competitive pool swimmers. The research contributes to a developing âsensory sociologyâ that highlights the importance of the socio-cultural framing of the senses and âsensory workâ, but where there remains a dearth of sociological exploration into senses extending beyond the âclassic fiveâ sensorium. Drawing on data from a three-year ethnographic study of competitive swimmers in the UK, our analysis explores the rich sensuousities of swimming, and highlights the role of temperature as fundamentally affecting the affordances offered by the aquatic environment. The article contributes original theoretical perspectives to the sociology of the senses and of sport in addressing the ways in which social actors in the aquatic environment interact, both intersubjectively and intercorporeally, as thermal beings
Chitosan particles agglomerated scaffolds for cartilage and osteochondral tissue engineering approaches with adipose tissue derived stem cells
It is well accepted that natural tissue regeneration is unlikely to occur if the cells are not supplied with an extracellular matrix (ECM) substitute. With this goal, several different methodologies have been used to produce a variety of 3D scaffolds as artificial ECM substitutes suitable for bone and cartilage tissue engineering. Furthermore, osteochondral tissue engineering presents new challenges since the combination of scaffolding and co-culture requirements from both bone and cartilage applications is required in order to achieve a successful osteochondral construct.
In this paper, an innovative processing route based on a chitosan particles aggregation
methodology for the production of cartilage and osteochondral tissue engineering
scaffolds is reported. An extensive characterization is presented including a morphological evaluation using Micro-Computed Tomography (ÎŒCT) and 3D virtual models built with an image processing software. Mechanical and water uptake characterizations were also carried out, evidencing the potential of the developed scaffolds for the proposed applications. Cytotoxicity tests show that the developed chitosan particles agglomerated scaffolds do not exert toxic effects on cells. Furthermore, osteochondral bilayered scaffolds could also be developed. Preliminary seeding of mesenchymal stem cells isolated from
human adipose tissue was performed aiming at developing solutions for chondrogenic and
osteogenic differentiation for osteochondral tissue engineering applications.Fundação para a CiĂȘncia e a Tecnologia (FCT)European NoE EXPERTISSUES
(NMP3-CT-2004-500283)European STREP Project HIPPOCRATES
(NMP3-CT-2003-505758
Physics Opportunities of e+e- Linear Colliders
We describe the anticipated experimental program of an e+e- linear collider
in the energy range 500 GeV -- 1.5 TeV. We begin with a description of current
collider designs and the expected experimental environment. We then discuss
precision studies of the W boson and top quark. Finally, we review the range of
models proposed to explain the physics of electroweak symmetry breaking and
show, for each case, the central role that the linear collider experiments will
play in elucidating this physics. (to appear in Annual Reviews of Nuclear and
Particle Science)Comment: 93 pages, latex + 23 figures; typos corrections + 1 reference adde
Radio Galaxy Zoo: host galaxies and radio morphologies derived from visual inspection
We present results from the first 12 months of operation of Radio Galaxy Zoo, which upon completion will enable visual inspection of over 170000 radio sources to determine the host galaxy of the radio emission and the radio morphology. Radio Galaxy Zoo uses 1.4âGHz radio images from both the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) and the Australia Telescope Large Area Survey (ATLAS) in combination with mid-infrared images at 3.4âÎŒm from the Wide-field Infrared Survey Explorer (WISE) and at 3.6âÎŒm from the Spitzer Space Telescope. We present the early analysis of the WISE mid-infrared colours of the host galaxies. For images in which there is >75âperâcent consensus among the Radio Galaxy Zoo cross-identifications, the project participants are as effective as the science experts at identifying the host galaxies. The majority of the identified host galaxies reside in the mid-infrared colour space dominated by elliptical galaxies, quasi-stellar objects and luminous infrared radio galaxies. We also find a distinct population of Radio Galaxy Zoo host galaxies residing in a redder mid-infrared colour space consisting of star-forming galaxies and/or dust-enhanced non-star-forming galaxies consistent with a scenario of merger-driven active galactic nuclei (AGN) formation. The completion of the full Radio Galaxy Zoo project will measure the relative populations of these hosts as a function of radio morphology and power while providing an avenue for the identification of rare and extreme radio structures. Currently, we are investigating candidates for radio galaxies with extreme morphologies, such as giant radio galaxies, late-type host galaxies with extended radio emission and hybrid morphology radio source
MSSM Higgs-Boson Production at Hadron Colliders with Explicit CP Violation
Gluon fusion is the main production mechanism for Higgs bosons with masses up
to several hundred GeV in collisions at the CERN Large Hadron Collider. We
investigate the effects of the CP-violating phases on the fusion process
including both the sfermion-loop contributions and the one-loop induced
CP-violating scalar-pseudoscalar mixing in the minimal supersymmetric standard
model. With a universal trilinear parameter assumed, every physical observable
involves only the sum of the phases of the universal trilinear parameter
and the higgsino mass parameter . The phase affects the lightest
Higgs-boson production rate significantly through the neutral Higgs-boson
mixing and, for the masses around the lightest stop-pair threshold, it also
changes the production rate of the heavy Higgs bosons significantly through
both the stop and sbottom loops and the neutral Higgs-boson mixing.Comment: 28 pages, 8 figures. Some references and comments added. Typos
corrected. To appear in Phys. Rev.
The Search for Higgs particles at high-energy colliders: Past, Present and Future
I briefly review the Higgs sector in the Standard Model and its minimal
Supersymmetric extension, the MSSM. After summarizing the properties of the
Higgs bosons and the present experimental constraints, I will discuss the
prospects for discovering these particle at the upgraded Tevatron, the LHC and
a high-energy linear collider. The possibility of studying the
properties of the Higgs particles will be then summarized.Comment: 28 pages, latex, 15 figures, talk at WHEPP VII, Allahabad, Indi
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