24,759 research outputs found
Influence of Light and Heavy Thresholds on SUSY Unification
In this paper we study and compare susy unification using two different
approaches in order to take into account the effect of light particle
thresholds on the evolution of gauge couplings: the step--function
approximation, on the one hand, and a mass dependent procedure, which gives a
more accurate description of the dependence of the results on the masses, on
the other. We also include the effect of heavy thresholds, when is
chosen as the unifying group. We find that the mass--dependent procedure
excludes scenarios where all susy masses are below , and favors a value
of near its upper experimental bound, contrary to the results
obtained with the step--function approximation. We underline the dependence of
the results on the procedure chosen to deal with light thresholds.Comment: 18 pages,LAEFF-93/014,REVTEX-2.1, 5 figures not included, available
upon request (include FAX number)
Study of nanocrystals dispersed in amorphous matrix
Crystalline nanoparticles of cadmium iodide where suspended in the amorphous
matrix of antimony trisulphide. Both materials are layered structured and have
large band-gaps however cadmium iodide exhibits polytypism, i.e. it exists in
various different crystalline states. Different crystalline states are marked
by wholely different dielectric constants which give rise to sharp surface
plasmon resonance (SPR) peaks in the UV-visible. The manuscript details the
variation in SPR's with heat-treatment of the films.Comment: 10 pages 8 figures submitted to PR
Nanodiamond as a vector for siRNA delivery to Ewing sarcoma cells
We investigated the ability of diamond nanoparticles (nanodiamonds, NDs) to
deliver small interfering RNA (siRNA) in Ewing sarcoma cells, in the
perspective of in vivo anti-cancer nucleic acid drug delivery. siRNA was
adsorbed onto NDs previously coated with cationic polymer. Cell uptake of NDs
has been demonstrated by taking advantage of NDs intrinsic fluorescence coming
from embedded color center defects. Cell toxicity of these coated NDs was shown
to be low. Consistent with the internalization efficacy, we have shown a
specific inhibition of EWS/Fli-1 gene expression at the mRNA and protein level
by the ND vectorized siRNA in a serum containing medium
Do Deep Inelastic Scattering Data Favor a Light Gluino
A next--to--leading order QCD analysis of deep inelastic scattering data is
performed allowing for contributions due to a light gluino. We obtain the
values of for QCD, SUSY QCD with a Majorana gluino and a
Dirac gluino respectively. The value of \alsm obtained in SUSY QCD with a
Majorana gluino best agrees with the direct measurements of
at LEP.Comment: 8 pages with 7 pages of figures, DESY 94-00
Delta Baryon Magnetic Moments From Lattice QCD
Theoretical predictions for the magnetic moments of the physical Delta
baryons are extracted from lattice QCD calculations. We utilize finite-range
regulated effective field theory that is constructed to have the correct Dirac
moment mass dependence in the region where the up and down quark masses are
heavy. Of particular interest is the chiral nonanalytic behaviour encountered
as the nucleon-pion decay channel opens. We find a Delta^++ magnetic moment (at
the Delta pole) of 4.99 \pm 0.56 \mu_N. This result is within the Particle Data
Group range of 3.7-7.5 \mu_N and compares well with the experimental result of
Bosshard et al. of 4.52 \pm 0.51 \pm 0.45 \mu_N. The interplay between the
different pion-loop contributions to the Delta^+ magnetic moment leads to the
surprising result that the proton moment may exceed that of the Delta^+,
contrary to conventional expectations.Comment: 7 pages, 7 figures, RevTex 4; Updated to include a recent
experimental resul
Two-divisibility of the coefficients of certain weakly holomorphic modular forms
We study a canonical basis for spaces of weakly holomorphic modular forms of
weights 12, 16, 18, 20, 22, and 26 on the full modular group. We prove a
relation between the Fourier coefficients of modular forms in this canonical
basis and a generalized Ramanujan tau-function, and use this to prove that
these Fourier coefficients are often highly divisible by 2.Comment: Corrected typos. To appear in the Ramanujan Journa
Impact of Preoperative Bevacizumab on Complications After Resection of Colorectal Liver Metastases: Case-Matched Control Study
Background: Chemotherapy may increase postoperative morbidity and mortality after liver surgery. Especially bevacizumab, a monoclonal antibody against vascular endothelial growth factor (VEGF), could have a detrimental effect. To assess the impact of neoadjuvant bevacizumab on clinical outcome after hepatectomy for colorectal liver metastases (CRLMs) this case-matched control study was initiated. Methods: The multicentric data collection was performed in the Swiss HPB Center of the University Hospital Zurich (CH), the Department of Digestive Surgery and Transplantation Strasbourg (F), and the Division of Hepato-biliary-pancreatic surgery of "Josep Tureta” Hospital Girona (E). Consecutive patients operated onbetween July 2005 and December 2007 due to CRLMs who received neoadjuvant chemotherapy were assessed. Patients were divided in two groups: group A had neoadjuvant chemotherapy with bevacicumab, and group B had it without bevacizumab. Results: No differences in overall morbidity (56 vs. 40% in the bevacizumab and control groups, respectively, p=0.23) or mortality could be documented. Similarly, the incidence of severe postoperative complications was not statistically different between the bevacizumab and control groups (31 and 18%, respectively, p=0.31). Wound complications were comparable (11% in the bevacizumab group compared and 9% in the control group, p=1.00). However, bevacizumab was associated with a significantly decreased incidence of postoperative hepatic insufficiency (7 vs. 20%, p=0.03). Conclusions: No impact on the incidence or severity of complications by bevacizumab could be shown. Bevacizumab may even reduce the incidence of liver failure after liver surger
The Supersymmetric Particle Spectrum
We examine the spectrum of supersymmetric particles predicted by grand
unified theoretical (GUT) models where the electroweak symmetry breaking is
accomplished radiatively. We evolve the soft supersymmetry breaking parameters
according to the renormalization group equations (RGE). The minimization of the
Higgs potential is conveniently described by means of tadpole diagrams. We
present complete one-loop expressions for these minimization conditions,
including contributions from the matter and the gauge sectors. We concentrate
on the low fixed point region (that provides a natural explanation
of a large top quark mass) for which we find solutions to the RGE satisfying
both experimental bounds and fine-tuning criteria. We also find that the
constraint from the consideration of the lightest supersymmetric particle as
the dark matter of the universe is accommodated in much of parameter space
where the lightest neutralino is predominantly gaugino. The supersymmetric mass
spectrum displays correlations that are model-independent over much of the GUT
parameter space.Comment: 62 pages + 10 PS figures included (uuencoded), MAD/PH/80
Recommended from our members
ADC Nonlinearity Correction for the Majorana Demonstrator
Imperfections in analog-to-digital conversion (ADC) cannot be ignored when signal digitization requirements demand both wide dynamic range and high resolution, as is the case for the Majorana Demonstrator 76Ge neutrinoless double-beta decay search. Enabling the experiment's high-resolution spectral analysis and efficient pulse shape discrimination required careful measurement and correction of ADC nonlinearities. A simple measurement protocol was developed that did not require sophisticated equipment or lengthy data-taking campaigns. A slope-dependent hysteresis was observed and characterized. A correction applied to digitized waveforms prior to signal processing reduced the differential and integral nonlinearities by an order of magnitude, eliminating these as dominant contributions to the systematic energy uncertainty at the double-beta decay Q value
Treatment outcomes of new tuberculosis patients hospitalized in Kampala, Uganda: a prospective cohort study.
BACKGROUND: In most resource limited settings, new tuberculosis (TB) patients are usually treated as outpatients. We sought to investigate the reasons for hospitalisation and the predictors of poor treatment outcomes and mortality in a cohort of hospitalized new TB patients in Kampala, Uganda. METHODS AND FINDINGS: Ninety-six new TB patients hospitalised between 2003 and 2006 were enrolled and followed for two years. Thirty two were HIV-uninfected and 64 were HIV-infected. Among the HIV-uninfected, the commonest reasons for hospitalization were low Karnofsky score (47%) and need for diagnostic evaluation (25%). HIV-infected patients were commonly hospitalized due to low Karnofsky score (72%), concurrent illness (16%) and diagnostic evaluation (14%). Eleven HIV uninfected patients died (mortality rate 19.7 per 100 person-years) while 41 deaths occurred among the HIV-infected patients (mortality rate 46.9 per 100 person years). In all patients an unsuccessful treatment outcome (treatment failure, death during the treatment period or an unknown outcome) was associated with duration of TB symptoms, with the odds of an unsuccessful outcome decreasing with increasing duration. Among HIV-infected patients, an unsuccessful treatment outcome was also associated with male sex (P = 0.004) and age (P = 0.034). Low Karnofsky score (aHR = 8.93, 95% CI 1.88 - 42.40, P = 0.001) was the only factor significantly associated with mortality among the HIV-uninfected. Mortality among the HIV-infected was associated with the composite variable of CD4 and ART use, with patients with baseline CD4 below 200 cells/µL who were not on ART at a greater risk of death than those who were on ART, and low Karnofsky score (aHR = 2.02, 95% CI 1.02 - 4.01, P = 0.045). CONCLUSION: Poor health status is a common cause of hospitalisation for new TB patients. Mortality in this study was very high and associated with advanced HIV Disease and no use of ART
- …
