721 research outputs found
Unforeseen high temperature and humidity stability of FeCl intercalated few layer graphene
We present the first systematic study of the stability of the structure and
electrical properties of FeCl intercalated few-layer graphene to high
levels of humidity and high temperature. Complementary experimental techniques
such as electrical transport, high resolution transmission electron microscopy
and Raman spectroscopy conclusively demonstrate the unforeseen stability of
this transparent conductor to a relative humidity up to at room
temperature for 25 days, to a temperature up to 150\,^\circC in atmosphere
and up to a temperature as high as 620\,^\circC in vacuum, that is more than
twice higher than the temperature at which the intercalation is conducted. The
stability of FeCl intercalated few-layer graphene together with its unique
values of low square resistance and high optical transparency, makes this
material an attractive transparent conductor in future flexible electronic
applications.Comment: Scientific Reports, volume 5, article no. 760
Analyses of two and three pion Bose-Einstein Correlations using Coulomb wave functions
Using effective formulas we analyze the Bose-Einstein correlations (BEC) data
corrected for Coulomb interactions provided by STAR Collaboration and the
quasi-corrected data (raw data with acceptance correction etc) on 2\pi and 3\pi
BEC by using Coulomb wave function with coherence parameter included. The
corresponding magnitudes of the interaction regions turn out to be almost the
same: R_{Coul}(2\pi) \simeq \frac 32R_{Coul}(3\pi). R_{Coul} means the size of
interaction region obtained in terms of Coulomb wave function. This approximate
relation is also confirmed by the core-halo model. Moreover, the genuine 3rd
order term of BEC has also been investigated in this framework and its
magnitude has been estimated both in the fully corrected data and in the
quasi-corrected data.Comment: 12 pages, 5 figure
What information can we obtain from the yield ratio in heavy-ion collisions ?
The recently reported data on the yield ratio in central
rapidity region of heavy-ion collisions are analyzed by theoretical formula
which accounts for Coulomb interaction between central charged fragment (CCF)
consisting of nearly stopped nucleons with effective charge
Z_{\mbox{\scriptsize eff}} and charged pions produced in the same region of
the phase space. The Coulomb wave function method is used instead of the usual
Gamow factor in order to account for the finite production range of pions,
. For Gaussian shape of the pion production sources it results in a
quasi-scaling in and Z_{\mbox{\scriptsize eff}} which makes
determination of parameters and Z_{\mbox{\scriptsize eff}} from the
existing experimental data difficult. Only sufficiently accurate data taken in
the extreme small - region, where this
quasi-scaling is broken, could be used for this purpose.Comment: 7 pages, Latex type, 8 figure
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Some experimental considerations of the QCD Group
For experimental investigation of quantum chromodynamics, the preferred machine question is dominated by such issues as how much luminosity is needed and which machine is practical (to get approved, build fast, run reliably, etc.). It is concluded that pile-up problems for localized E/sub T/ triggers are not serious. For high luminosity QCD studies a philosophy is envisaged which is predominantly calorimetric and ignores the low p/sub t/ activity. It is suggested that consideration be given to the concept of a jet spectrometer for jet fragmentation with momentum measurement. (LEW
Quasiscaling in the analysis of the yield ratio : Mathematical structure and estimation of source size
Recently we have found that integral of the squared Coulomb wave function
describing systemcomposed of charged pion and central charged fragment
protons, , times pion source function (of
the size ), \intdr |\psi_r(r)|^2 \rho(r), shows a quasiscaling
behavior. This is approximately invariant under the following transformation:
; . We called
such behavior quasiscaling. We examine this quasiscaling
behavior in detail. In particular we provide a semi-analytical examination of
this behavior and confirm it for the exponential pionic source functions in
addition to the Gaussian ones and for the production of K mesons as well. When
combined with the results of the HBT, a result of the yield ratio allows us to
estimate the size of the central charged fragment (CCF) to be for Pb+Pb collisions at energy 158 GeV/nucleon. From our
estimation, the baryon number density [1/fm^3] is
obtained.Comment: 7 pages, RevTex, 6figure
The multiple sclerosis risk sharing scheme monitoring study - early results and lessons for the future
Background: Risk sharing schemes represent an innovative and important approach to the problems of rationing and achieving cost-effectiveness in high cost or controversial health interventions. This study aimed to assess the feasibility of risk sharing schemes, looking at long term clinical outcomes, to determine the price at which high cost treatments would be acceptable to the NHS.
Methods: This case study of the first NHS risk sharing scheme, a long term prospective cohort study of beta interferon and glatiramer acetate in multiple sclerosis ( MS) patients in 71 specialist MS centres in UK NHS hospitals, recruited adults with relapsing forms of MS, meeting Association of British Neurologists (ABN) criteria for disease modifying therapy. Outcome measures were: success of recruitment and follow up over the first three years, analysis of baseline and initial follow up data and the prospect of estimating the long term cost-effectiveness of these treatments.
Results: Centres consented 5560 patients. Of the 4240 patients who had been in the study for a least one year, annual review data were available for 3730 (88.0%). Of the patients who had been in the study for at least two years and three years, subsequent annual review data were available for 2055 (78.5%) and 265 (71.8%) patients respectively. Baseline characteristics and a small but statistically significant progression of disease were similar to those reported in previous pivotal studies.
Conclusion: Successful recruitment, follow up and early data analysis suggest that risk sharing schemes should be able to deliver their objectives. However, important issues of analysis, and political and commercial conflicts of interest still need to be addressed
Two-kaon correlations in central Pb + Pb collisions at 158 A GeV/c
Two-particle interferometry of positive kaons is studied in Pb + Pb
collisions at mean transverse momenta and 0.91 GeV/c. A
three-dimensional analysis was applied to the lower data, while a
two-dimensional analysis was used for the higher data. We find that the
source size parameters are consistent with the scaling curve observed in
pion correlation measurements in the same collisions, and that the duration
time of kaon emission is consistent with zero within the experimental
sensitivity.Comment: 4 pages incl. 1 table and 3 fig's; RevTeX; accepted for publication
in PR
Non-Invasive Cytology Brush PCR Diagnostic Testing in Mucosal Leishmaniasis: Superior Performance to Conventional Biopsy with Histopathology
Traditional methods of diagnosing mucosal leishmaniasis (ML), such as biopsy with histopathology, are insensitive and require collection of an invasive diagnostic specimen. species identification was performed by PCR-based assays of positive specimens. (n = 3).Use of commercial grade cytology brush PCR for diagnosis of ML is sensitive, rapid, well tolerated, and carries none of the risks of invasive diagnostic procedures such as biopsy. Further optimization is required for adequate species identification. Further evaluation of this method in field and other settings is warranted
Leading particle effect, inelasticity and the connection between average multiplicities in {\bf } and {\bf } processes
The Regge-Mueller formalism is used to describe the inclusive spectrum of the
proton in collisions. From such a description the energy dependences of
both average inelasticity and leading proton multiplicity are calculated. These
quantities are then used to establish the connection between the average
charged particle multiplicities measured in {\bf } and {\bf } processes. The description obtained for the leading proton cross section
implies that Feynman scaling is strongly violated only at the extreme values of
, that is at the central region () and at the diffraction
region (), while it is approximately observed in the
intermediate region of the spectrum.Comment: 20 pages, 10 figures, to be published in Physical Review
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