2,511 research outputs found
Electroweak radiative corrections to the Higgs-boson production in association with -boson pair at colliders
We present the full electroweak radiative
corrections to the Higgs-boson production in association with -boson pair
at an electron-positron linear collider(LC) in the standard model. We analyze
the dependence of the full one-loop corrections on the Higgs-boson mass
and colliding energy . We find that the corrections significantly
suppress the Born cross section, and the electroweak
radiative corrections are generally between 1.0% and -15% in our chosen
parameter space, which should be taken into consideration in the future precise
experiments.Comment: 19 pages, 7 figures, to be published on Phys. ReV.
Galaxy formation and cosmic-ray acceleration in a magnetized universe
We study the linear magneto-hydrodynamical behaviour of a Newtonian cosmology
with a viscous magnetized fluid of finite conductivity and generalise the Jeans
instability criterion. The presence of the field favors the anisotropic
collapse of the fluid, which in turn leads to further magnetic amplification
and to an enhanced current-sheet formation in the plane normal to the ambient
magnetic field. When the currents exceed a certain threshold, the resulting
electrostatic turbulence can dramatically amplify the resistivity of the medium
(anomalous resistivity). This could trigger strong electric fields and
subsequently the acceleration of ultra-high energy cosmic rays (UHECRs) during
the formation of protogalactic structures.Comment: 10 pages, ApJL in pres
From 2D conformal to 4D self-dual theories: quaternionic analyticity
It is shown that self-dual theories generalize to four dimensions both the
conformal and analytic aspects of two-dimensional conformal field theories. In
the harmonic space language there appear several ways to extend complex
analyticity (natural in two dimensions) to quaternionic analyticity (natural in
four dimensions). To be analytic, conformal transformations should be realized
on , which appears as the coset of the complexified conformal group
modulo its maximal parabolic subgroup. In this language one visualizes the
twistor correspondence of Penrose and Ward and consistently formulates the
analyticity of Fueter.Comment: 24 pages, LaTe
Polyclonal epitope mapping reveals temporal dynamics and diversity of human antibody responses to H5N1 vaccination
Novel influenza A virus (IAV) strains elicit recall immune responses to conserved epitopes, making them favorable antigenic choices for universal influenza virus vaccines. Evaluating these immunogens requires a thorough understanding of the antigenic sites targeted by the polyclonal antibody (pAb) response, which single-particle electron microscopy (EM) can sensitively detect. In this study, we employ EM polyclonal epitope mapping (EMPEM) to extensively characterize the pAb response to hemagglutinin (HA) after H5N1 immunization in humans. Cross-reactive pAbs originating from memory B cells immediately bound the stem of HA and persisted for more than a year after vaccination. In contrast, de novo pAb responses to multiple sites on the head of HA, targeting previously determined key neutralizing sites on H5 HA, expanded after the second immunization and waned quickly. Thus, EMPEM provides a robust tool for comprehensively tracking the specificity and durability of immune responses elicited by novel universal influenza vaccine candidates
Tin‐Containing Graphite for Sodium‐Ion Batteries and Hybrid Capacitors
The limited Na-storage capacity of graphite anodes for sodium-ion batteries (∼110 mAh g−1) is significantly enhanced by the incorporation of nanosized Sn (17 wt%). The composite (SntGraphite), prepared by simple annealing of graphite with SnCl2, shows a specific capacity of 223 mAh g−1 (at 50 mA g−1) combined with excellent cycle life (i. e., 96 % of capacity retention after 2,200 cycles at 1 A g−1) and initial Coulomb efficiency (90 %). The combined storage of sodium in graphite (by solvent co-intercalation) and Sn (by alloy formation) is followed by in situ X-ray diffraction and in situ electrochemical dilatometry (ECD). While the additional tin almost doubles the electrode capacity, its contribution to the electrode expansion (∼3 %) is surprisingly small. The use of SntGraphite as anode for sodium-ion hybrid capacitors with activated carbon as cathode provides a maximum energy and power density of ∼93 Wh kg−1 and 7.8 kW kg−1, with a capacity retention of ∼80 % after 8,000 cycles.Peer Reviewe
Tin-Containing Graphite for Sodium-Ion Batteries and Hybrid Capacitors
The limited Na-storage capacity of graphite anodes for sodium-ion batteries (∼110 mAh g−1) is significantly enhanced by the incorporation of nanosized Sn (17 wt%). The composite (SntGraphite), prepared by simple annealing of graphite with SnCl2, shows a specific capacity of 223 mAh g−1 (at 50 mA g−1) combined with excellent cycle life (i. e., 96 % of capacity retention after 2,200 cycles at 1 A g−1) and initial Coulomb efficiency (90 %). The combined storage of sodium in graphite (by solvent co-intercalation) and Sn (by alloy formation) is followed by in situ X-ray diffraction and in situ electrochemical dilatometry (ECD). While the additional tin almost doubles the electrode capacity, its contribution to the electrode expansion (∼3 %) is surprisingly small. The use of SntGraphite as anode for sodium-ion hybrid capacitors with activated carbon as cathode provides a maximum energy and power density of ∼93 Wh kg−1 and 7.8 kW kg−1, with a capacity retention of ∼80 % after 8,000 cycles.Peer Reviewe
Adaptation of a visualized loop-mediated isothermal amplification technique for field detection of Plasmodium vivax infection
<p>Abstract</p> <p>Background</p> <p>Loop-mediated isothermal amplification (LAMP) is a high performance method for detecting DNA and holds promise for use in the molecular detection of infectious pathogens, including <it>Plasmodium </it>spp. However, in most malaria-endemic areas, which are often resource-limited, current LAMP methods are not feasible for diagnosis due to difficulties in accurately interpreting results with problems of sensitive visualization of amplified products, and the risk of contamination resulting from the high quantity of amplified DNA produced. In this study, we establish a novel visualized LAMP method in a closed-tube system, and validate it for the diagnosis of malaria under simulated field conditions.</p> <p>Methods</p> <p>A visualized LAMP method was established by the addition of a microcrystalline wax-dye capsule containing the highly sensitive DNA fluorescence dye SYBR Green I to a normal LAMP reaction prior to the initiation of the reaction. A total of 89 blood samples were collected on filter paper and processed using a simple boiling method for DNA extraction, and then tested by the visualized LAMP method for <it>Plasmodium vivax </it>infection.</p> <p>Results</p> <p>The wax capsule remained intact during isothermal amplification, and released the DNA dye to the reaction mixture only when the temperature was raised to the melting point following amplification. Soon after cooling down, the solidified wax sealed the reaction mix at the bottom of the tube, thus minimizing the risk of aerosol contamination. Compared to microscopy, the sensitivity and specificity of LAMP were 98.3% (95% confidence interval (CI): 91.1-99.7%) and 100% (95% CI: 88.3-100%), and were in close agreement with a nested polymerase chain reaction method.</p> <p>Conclusions</p> <p>This novel, cheap and quick visualized LAMP method is feasible for malaria diagnosis in resource-limited field settings.</p
Anomalous coupling effects in exclusive radiative B-meson decays
The top-quark FCNC processes will be searched for at the CERN LHC, which are
correlated with the B-meson decays. In this paper, we study the effects of
top-quark anomalous interactions in the exclusive radiative and decays. With the current experimental data of
the branching ratios, the direct CP and the isospin asymmetries, bounds on the
coupling from and
from decays are derived,
respectively. The bound on from is generally compatible with that from . However, the isospin asymmetry further
restrict the phase of , and the combined bound results
in the upper limit, , which is lower than the
CDF result. For real , the upper bound on is about of the same order as the discovery
potential of ATLAS with an integrated luminosity of . For
decays, the NP contribution is enhanced by a large CKM factor
, and the constraint on coupling is rather
restrictive, . With refined
measurements to be available at the LHCb and the future super-B factories, we
can get close correlations between and the rare
decays, which will be studied directly at the LHC ATLAS and CMS.Comment: 25 pages, 15 figures, pdflate
Relationship between quantitative CT metrics and health status and BODE in chronic obstructive pulmonary disease
Background The value of quantitative CT (QCT) to
identify chronic obstructive pulmonary disease (COPD)
phenotypes is increasingly appreciated. The authors
hypothesised that QCT-defined emphysema and airway
abnormalities relate to St George’s Respiratory
Questionnaire (SGRQ) and Body-Mass Index, Airflow
Obstruction, Dyspnea and Exercise Capacity Index
(BODE).
Methods 1200 COPDGene subjects meeting Global
Initiative for Chronic Obstructive Lung Disease (GOLD)
criteria for COPD with QCT analysis were included. Total
lung emphysema was measured using the density mask
technique with a 950 Hounsfield unit threshold. An
automated programme measured mean wall thickness
(WT), wall area percentage (WA%) and 10 mm lumenal
perimeter (pi10) in six segmental bronchi. Separate
multivariate analyses examined the relative influence of
airway measures and emphysema on SGRQ and BODE.
Results In separate models predicting SGRQ score, a 1
unit SD increase in each airway measure predicted higher
SGRQ scores (for WT, 1.90 points higher, p=0.002; for
WA%, 1.52 points higher, p=0.02; for pi10, 2.83 points
higher p<0.001). The comparable increase in SGRQ for
a 1 unit SD increase in emphysema percentage in these
models was relatively weaker, significant only in the pi10
model (for emphysema percentage, 1.45 points higher,
p=0.01). In separate models predicting BODE, a 1 unit
SD increase in each airway measure predicted higher
BODE scores (for WT, 1.07-fold increase, p<0.001; for
WA%, 1.20-fold increase, p<0.001; for pi10, 1.16-fold
increase, p<0.001). In these models, emphysema more
strongly influenced BODE (range 1.24-1.26-fold increase,
p<0.001).
Conclusion Emphysema and airway disease both relate
to clinically important parameters. The relative influence
of airway disease is greater for SGRQ; the relative
influence of emphysema is greater for BODE.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91946/1/2012 Thorax Relationship between quantitative CT metrics and health status and BODE in chronic obstructive pulmonary disease.pd
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