317 research outputs found
Validity of quasi-degenerate neutrino mass models and their predictions on baryogenesis
Quasi-degenerate neutrino mass models (QDN) which can explain the current
data on neutrino masses and mixings,are studied. In the first part, we study
the effect of CP-phases on QDN mass matrix obeying symmetry in
normal hierarchical (QD-NH) and inverted hierarchical (QD-IH) patterns.The
numerical predictions are consistent with observed data on solar mixing angle,
absolute neutrino mass parameter consistent with neutrinoless double beta decay
mass parameter and sum of three absolute neutrino masses from cosmological
bound.The neutrino mass matrix is parameterized using only two unknown
parameters. The second part deals with the estimation of observed baryon
asymmetry of the universe. The prediction is nearly consistent with observation
with flavoured thermal leptogenesis scenario. QD-NH model appears to be more
favourable than those of QD-IH models.The present analysis shows that the three
absolute neutrino masses may exhibit quasi-degenerate pattern in nature. They
are far from discrimination at the moment.Comment: 17 pages, no figure, poster presentation in the 25th International
Conference on neutrino physics and Astrophysics, Kyoto, Japan, July,201
Higgs sector and R-parity breaking couplings in models with broken U(1)_B-L gauge symmetry
Four different supersymmetric models based on SU(2)_L X U(1)_R X U(1)_B-L and
SU(2)_L X SU(2)_R X U(1)_B-L gauge symmetry groups are studied. U(1)_B-L
symmetry is broken spontaneously by a vacuum expectation value (VEV) of a
sneutrino field. The right-handed gauge bosons may obtain their mass solely by
sneutrino VEV. The physical charged lepton and neutrino are mixtures of
gauginos, higgsinos and lepton interaction eigenstates. Explicit formulae for
masses and mixings in the physical lepton fields are found. The spontaneous
symmetry breaking mechanism fixes the trilinear R-parity breaking couplings.
Only some special R-parity breaking trilinear couplings are allowed. There is a
potentially large trilinear lepton number breaking coupling - which is unique
to left-right models - that is proportional to the SU(2)_R gauge coupling g_R.
The couplings are parametrized by few mixing angles, making the spontaneous
R-parity breaking a natural ``unification framework'' for R-parity breaking
couplings in SUSYLR models.Comment: 19 pages, no figures, uses REVTeX. To be published in PR
Nutrigenomics: future for sustenance
Nutrigenomics deals with the effect of foods and food constituents on gene expression. It is a new concept in disease prevention and cure. Nutrigenomics conveys how nutrients influence our body to express genes, whereas nutrigenetics refers to how our body responds to nutrients. The various bioactive food components can alter the gene expression mechanisms. But our actual knowledge is so insufficient that the only use of such information may help to satisfy our imagination. If science could arrive at some more precise facts, that would have vast applications in medicine
Evaluating Multiway Multilingual NMT in the Turkic Languages
Despite the increasing number of large and comprehensive machine translation (MT) systems, evaluation of these methods in various languages has been restrained by the lack of high-quality parallel corpora as well as engagement with the people that speak these languages. In this study, we present an evaluation of state-of-the-art approaches to training and evaluating MT systems in 22 languages from the Turkic language family, most of which being extremely under-explored. First, we adopt the TIL Corpus with a few key improvements to the training and the evaluation sets. Then, we train 26 bilingual baselines as well as a multi-way neural MT (MNMT) model using the corpus and perform an extensive analysis using automatic metrics as well as human evaluations. We find that the MNMT model outperforms almost all bilingual baselines in the out-of-domain test sets and finetuning the model on a downstream task of a single pair also results in a huge performance boost in both low- and high-resource scenarios. Our attentive analysis of evaluation criteria for MT models in Turkic languages also points to the necessity for further research in this direction. We release the corpus splits, test sets as well as models to the public.Peer reviewe
b -> s gamma in the left-right supersymmetric model
The rare decay is studied in the left-right supersymmetric
model. We give explicit expressions for all the amplitudes associated with the
supersymmetric contributions coming from gluinos, charginos and neutralinos in
the model to one-loop level. The branching ratio is enhanced significantly
compared to the standard model and minimal supersymmetric standard model values
by contributions from the right-handed gaugino and squark sector. We give
numerical results coming from the leading order contributions. If the only
source of flavor violation comes from the CKM matrix, we constrain the scalar
fermion-gaugino sector. If intergenerational mixings are allowed in the squark
mass matrix, we constrain such supersymmetric sources of flavor violation. The
decay sets constraints on the parameters of the model and
provides distinguishing signs from other supersymmetric scenarios.Comment: 12 figure
Simple supersymmetric solution to the strong CP problem
It is shown that the minimal supersymmetric left-right model can provide a
natural solution to the strong {\it CP} problem without the need for an axion,
nor any additional symmetries beyond supersymmetry and parity.Comment: Plain Latex. 10 pages, including two figures which are part of the
Latex file. Shortened version, to appear in Phys. Rev. Lett. 7
Advanced heart failure in adult congenital heart disease: the role of renal dysfunction in management and outcomes
Aims Previous studies in adult congenital heart disease (CHD) have demonstrated a link between renal dysfunction and mortality. However, the prognostic significance of renal dysfunction in CHD and decompensated heart failure (HF) remains unclear. We sought to assess the association between renal dysfunction and outcomes in adults with CHD presenting to our centre with acute HF between 2010 and 2021. Methods and results This retrospective analysis focused on the association between renal dysfunction, pre-existing and on admission, and outcomes during and after the index hospitalization. Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate <60 mL/min/1.73 m2. Cox regression analysis was used to identify the predictors of death post-discharge. In total, 176 HF admissions were included (mean age 47.7 ± 14.5 years, 43.2% females). One-half of patients had a CHD of great complexity, 22.2% had a systemic right ventricle, and 18.8% had Eisenmenger syndrome. Chronic kidney disease was present in one-quarter of patients. The median length of intravenous diuretic therapy was 7 (4–12) days, with a maximum dose of 120 (80–160) mg furosemide equivalents/day, and 15.3% required inotropic support. The in-hospital mortality rate was 4.5%. The 1- and 5-year survival rates free of transplant or ventricular assist device (VAD) post-discharge were 75.4% [95% confidence interval (CI): 69.2–82.3%] and 43.3% (95% CI: 36–52%), respectively. On multivariable Cox analysis, CKD was the strongest predictor of mortality or transplantation/VAD. Highly complex CHD and inpatient requirement of inotropes also remained predictive of an adverse outcome. Conclusion Adult patients with CHD admitted with acute HF are a high-risk cohort. CKD is common and triples the risk of death/transplantation/VAD. An expert multidisciplinary approach is essential for optimizing outcomes
Infrared Imaging of SDSS Quasars: Implications for the Quasar K correction
We have imaged 45 quasars from the Sloan Digital Sky Survey (SDSS) with
redshifts 1.85 < z < 4.26 in JHKs with the KPNO SQIID imager. By combining
these data with optical magnitudes from the SDSS we have computed the restframe
optical spectral indices of this sample and investigate their relation to
quasar redshift. We find a mean spectral index of = -0.55+/-0.42 with
a large spread in values. We also find possible evolution of the form alpha_o =
(0.148+/-0.068)z - (0.964+/-0.200)$ in the luminosity range -28.0 < M_i <
-26.5. Such evolution suggests changes in the accretion process in quasars with
time and is shown to have an effect on computed quasar luminosity functions.Comment: 20 pages, 10 figures, 3 tables, accepted to the Astronomical Journa
Solution to the Strong CP Problem: Supersymmetry with Parity
There is a natural solution to the strong CP problem in the Minimal
Supersymmetric Standard Model if it arises from a parity symmetric theory which
is spontaneously broken to MSSM at Planck, GUT or intermediate scales. The
strong CP phase is zero at the tree level and is not induced to two loops. The
SUSY phase problems are also solved. The universal soft SUSY breaking
parameters A, B, \mu, m_{1/2} are all automatically real and the only
additional CP violation effects of the low-energy MSSM are characterized by a
Hermitian squark mass matrix whose phases depend on the CKM phase. Cases with
non-universal boundary conditions are also considered.Comment: Typo in an equation corrected. Results unchanged. 8 pages, Late
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