833 research outputs found
Combining ability studies in restorer lines of sunflower (Helianthus annuus L.)
The restorer lines are used to get fertile hybrids in hybrid seed production system of sunflower. Improve-ment of R-lines for fertility and oil content of sunflower is required to get desirable hybrids upon crossing. In the pre-sent study, 6 restorer lines were crossed in full diallele and both direct and reciprocal crosses along with parents were evaluated for their combining ability. The analysis of variance revealed higher magnitude of SCA variance than GCA variance for all the characters studied except for days to 50 per cent flowering. Among six parents, GMU -520 and R-GM-41 were best general combiner for plant height, head diameter, test weight and leaf size in the desired direction. However, GMU-520 has advantage of yield per plant and oil content. From 15 direct crosses R-GM-41 x R -GM-49 exhibited significant specific combining ability for viz., days to 50 per cent flowering (-1.08), plant height (13.69), head diameter (4.79), leaf size (0.74), yield per plant (17.14), volume weight (2.54), test weight (1.75) and oil content (0.34) followed by RCR-630 x GMU-520, R-GM-41 x EC-602060, R-GM-49 x GMU-520 and EC-602060 x GMU-520 each exhibiting good specific combining ability for majority of characters. Among reciprocal crosses R-GM -41 x RCR-8 exhibited a high reciprocal effects for head diameter (4.57), yield per plant (15.16), test weight (2.02) and leaf size (0.75)
Learning internal iliac artery ligation and pelvic ureter course through cadaveric dissections
Background: Few surgical procedures, although vital, are not learnt and mastered during postgraduate courses in Obstetrics and Gynecology. Internal iliac artery ligation and tracing course of ureter are few of such surgical procedures. Cadaveric dissection sessions organized during postgraduate courses and as CME sessions (continued medical education) have proved useful in learning such unlearnt procedures. This article shares experiences from teaching internal iliac artery ligation, pelvic ureter course tracing and principles of many other unusual gynaecological surgical procedures to Obstetrics and Gynecology specialists and postgraduate students through CME programs involving cadaveric dissection.Methods: This involved organizing and conducting four cadaveric dissection CME workshops at three different teaching institutions. The components of these CMEs were lectures with power point presentations and two-way audio-visual interactive sessions while pelvic anatomy was demonstrated on cadavers through live dissections. Each CME was concluded by tactile experience to each delegate by handling the dissected cadavers; this was made possible by limiting delegate registration to 50 at each CME.Results: The surgical skills of internal iliac artery ligation and tracing course of pelvic ureter, which are not adequately and confidently learnt in routine postgraduate tenure, could be effectively transferred through cadaveric dissection.Conclusions: Revisiting anatomy dissection halls helps in learning rare but lifesaving surgical techniques. This can be achieved by arranging cadaveric dissection CMEs for practicing specialists. Such CMEs should be organized regularly and should be integrated into postgraduate curriculum
Large Non-perturbative Effects of Small \Delta m^2_{21}/\Delta m^2_{31} and \sin \theta_{13} on Neutrino Oscillation and CP Violation in Matter
In the framework of three generations, we consider the CP violation in
neutrino oscillation with matter effects. At first, we show that the
non-perturbative effects of two small parameters, \Delta m_{21}^2/\Delta
m_{31}^2 and \sin \theta_{13}, become more than 50% in certain ranges of energy
and baseline length. This means that the non-perturbative effects should be
considered in detailed analysis in the long baseline experiments. Next, we
propose a method to include these effects in approximate formulas for
oscillation probabilities. Assuming the two natural conditions,
\theta_{23}=45^\circ and the fact that the matter density is symmetric, a set
of approximate formulas, which involve the non-perturbative effects, has been
derived in all channels.Comment: 25 pages, 4 figures, version to appear in JHE
Very Long Baseline Neutrino Oscillation Experiment for Precise Measurements of Mixing Parameters and CP Violating Effects
We analyze the prospects of a feasible, Brookhaven National Laboratory based,
very long baseline (BVLB) neutrino oscillation experiment consisting of a
conventional horn produced low energy wide band beam and a detector of 500 kT
fiducial mass with modest requirements on event recognition and resolution.
Such an experiment is intended primarily to determine CP violating effects in
the neutrino sector for 3-generation mixing. We analyze the sensitivity of such
an experiment. We conclude that this experiment will allow determination of the
CP phase and the currently unknown mixing parameter
, if , a value times
lower than the present experimental upper limit. In addition to
and , the experiment has great potential for precise measurements
of most other parameters in the neutrino mixing matrix including , , ,
and the mass ordering of neutrinos through the observation of the matter effect
in the appearance channel.Comment: 12 pages, 10 figure
Tests of the Standard Model Using Muon Polarization Asymmetries in Kaon Decays
We have examined the physics and the experimental feasibility of studying
various kaon decay processes in which the polarization of a muon in the final
state is measured. Valuable information on CP violation, the quark mixing (CKM)
matrix, and new physics can be obtained from such measurements. We have
considered muon polarization in K_L to mu+ mu- and K to pi mu+ mu- decays.
Although the effects are small, or difficult to measure because of the small
branching ratios involved, these studies could provide clean measurements of
the CKM parameters. The experimental difficulty appears comparable to the
observation of K to pi nu barnu. New sources of physics, involving non-standard
CP violation, could produce effects observable in these measurements. Limits
from new results on the neutron and electron electric dipole moment, and
epsilon-prime over epsilon in neutral kaon decays, do not eliminate certain
models that could contribute to the signal. A detailed examination of muon
polarization out of the decay plane in KMU3 and radiative KMU2 decays also
appears to be of interest. With current kaon beams and detector techniques, it
is possible to measure the T-violating polarization for KMU3 with uncertainties
approaching 0.0001. This level of sensitivity would provide an interesting
probe of new physics.Comment: 24 pages, 3 figures, To be published in the International Journal of
Modern Physics
Experiment Simulation Configurations Used in DUNE CDR
The LBNF/DUNE CDR describes the proposed physics program and experimental
design at the conceptual design phase. Volume 2, entitled The Physics Program
for DUNE at LBNF, outlines the scientific objectives and describes the physics
studies that the DUNE collaboration will perform to address these objectives.
The long-baseline physics sensitivity calculations presented in the DUNE CDR
rely upon simulation of the neutrino beam line, simulation of neutrino
interactions in the far detector, and a parameterized analysis of detector
performance and systematic uncertainty. The purpose of this posting is to
provide the results of these simulations to the community to facilitate
phenomenological studies of long-baseline oscillation at LBNF/DUNE.
Additionally, this posting includes GDML of the DUNE single-phase far detector
for use in simulations. DUNE welcomes those interested in performing this work
as members of the collaboration, but also recognizes the benefit of making
these configurations readily available to the wider community.Comment: 9 pages, 4 figures, configurations in ancillary file
Improved Measurement of the K+ to pi+ nu nubar Branching Ratio
An additional event near the upper kinematic limit for K+ to pi+ nu nubar has
been observed by Experiment E949 at Brookhaven National Laboratory. Combining
previously reported and new data, the branching ratio is B(K+ to pi+ nu nubar)=
1.47 (+1.30, - 0.89) x 10-10 based on three events observed in the pion
momentum region 211<P<229 MeV/c. At the measured central value of the branching
ratio, the additional event had a signal-to-background ratio of 0.9
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