4,908 research outputs found
Hydrography of the Andaman sea during late Winter
179-189Distributions of temperature, salinity, density and dissolved oxygen during late winter in the Andaman Sea are presented by series of vertical sections and spatial distribution charts; study of the field of motion on dynamic computations is also included. Surface temperature exceeds 28°C over most of the northern Andaman Sea. Surface salinity increases from 31.0% in the northern regions to 32.8% in the southern regions. Density distribution in the upper 50 m is primarily controlled by the salinity distribution. Below the sill depth (1300 m), the water mass is characterized by uniform values of temperature, salinity and dissolved oxygen. Geostrophic circulation in the upper layer indicates the formation of cells (100-200 km), and the upper layer dynamics seem to be governed by the fresh water discharge into the region
Modeling charge transport in Swept Charge Devices for X-ray spectroscopy
We present the formulation of an analytical model which simulates charge
transport in Swept Charge Devices (SCDs) to understand the nature of the
spectral redistribution function (SRF). We attempt to construct the
energy-dependent and position dependent SRF by modeling the photon interaction,
charge cloud generation and various loss mechanisms viz., recombination,
partial charge collection and split events. The model will help in optimizing
event selection, maximize event recovery and improve spectral modeling for
Chandrayaan-2 (slated for launch in 2014). A proto-type physical model is
developed and the algorithm along with its results are discussed in this paper.Comment: 9 pages, 7 figures, Proc. SPIE 8453, High Energy, Optical, and
Infrared Detectors for Astronomy
Assessment of insecticides and Cry2AB toxin resistance development in Karnataka population of Plutella xylostella (Linn.)
Insecticidal resistance studies against third instar larvae of DBM (Plutella xylostella L.) were carried out to know the rate of development of resistance from F1 to F3 generations in Karnataka population. The third instar larvae obtained from field were subjected to bioassay studies with tested against acephate, cypermethrin, spinosad, cartap hydrochloride and Cry2Ab toxin using leaf dip method to calculate LC50 values. The LC50 values of the insecticides were further used to quantify the resistance in P. xylostella of parental generation (F0) from Karnataka field population. The survivals from F0 generation were reared to next generation (F1). Resistance development studies was assessed from F1 to F3 generation with third instar larvae in every generation with a concentration that caused 80.00 % mortality for all the test insecticides and Cry2Ab toxin. Results revealed that ((0.17 folds) no resistance was developed against acephate in F3 generation. In case of cypermethrin 2.33 folds. Resistance studies further revealed that 1.50 folds resistance was developed against spinosad, 2.28 folds against cartap hydrochloride and Cry2Ab toxin 1.49 folds resistance was recorded in F3 generation. The rate of development of resistance from F1 to F3 generations increased in all the test insecticides and Cry toxin, except against acephate in Karnataka population. This data will be useful in the development of insecticide resistance management approach for DBM
Genetic diversity assessment using RAPD primers in insecticide resistant populations of diamondback moth Plutella xylostella (Linn.)
Genetic diversity in acephate, spinosad and Cry2Ab resistant Plutella xylostella collected from three states of India was assessed by RAPD markers. The DNA extracted from larvae was subjected to polymerase chain reaction using 10 RAPD primers. The highest number alleles (7) were produced by primer ABA-13, followed by six alleles each by primers ABA-2, 7, 8, 11, 14; five alleles each were produced by ABA-4, 9, 10, 12. UPGMA analysis clustered the acephate, spinosad and Cry2Ab treated P.xylostella populations into two groups with overall similarity level of 33%, 27% and 34% respectively. Cluster A consisted 11 samples while Cluster B consisted only F1 of acephate and spinosad treated Karnataka population. In Cry2Ab treated population Cluster B comprised 11 samples and Cluster A had out grouped singly i.e. F0 generation from Karnataka. The genetic variability between the acephate, spinosad and Cry2Ab treated populations ranged from 33 to 69%, 27 to 56% and 34 to 69% respectively. Acephate and spinosad treated F1 population and Cry2Ab treated F0 population from Karnataka were out grouped from rest of the populations
Eliminating the d=5 proton decay operators from SUSY GUTs
A general analysis is made of the question whether the d=5 proton decay
operators coming from exchange of colored Higgsinos can be completely
eliminated in a natural way in supersymmetric grand unified models. It is shown
that they can indeed be in SO(10) while at the same time naturally solving the
doublet-triplet splitting problem, having only two light Higgs doublets, and
using no more than a single adjoint Higgs field. Accomplishing all of this
requires that the vacuum expectation value of the adjoint Higgs field be
proportional to the generator I_{3R} rather than to B-L, as is usually assumed.
It is shown that such models can give realistic quark and lepton masses. We
also point out a new mechanism for solving the \mu problem in the context of
SO(10) SUSY GUTs.Comment: 24 pages in LaTeX, with 3 figure
Increased Levels of Serum Granulocyte-Macrophage Colony-Stimulating Factor Is Associated with Activated Peripheral Dendritic Cells in Type 2 Diabetes Subjects (CURES-99)
Background: Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a pro-inflammatory cytokine with
growth factor–like properties for monocytes and dendritic cells (DCs). In the present study, serum GM-CSF
levels and the activation status of DCs were studied in type 2 diabetes mellitus (T2DM) subjects.
Methods: Study subjects were recruited from the Chennai Urban Rural Epidemiology Study. Healthy controls
(n = 45) and T2DM patients (n = 45) were included in the study. Serum levels of GM-CSF, interleukin-1b, interleukin-
6, and tumor necrosis factor-a were measured. Enumeration of circulating DCs (myeloid [m] and plasmocytoid
[p]) and its surface antigen expression were quantified by flow cytometry.
Results: The serum GM-CSF levels were significantly higher among diabetes subjects compared with subjects
without diabetes and showed a positive correlation with glycated hemoglobin (r = 0.208, P = 0.018). The serum
GM-CSF levels were lower in subjects on combined insulin and oral hypoglycemic agents (OHA) treatment
(1.09 pg/mL) compared with those taking OHA alone (1.9 pg/mL). The increased GM-CSF levels were associated
with the activated phenotype of mDCs and pDCs, as determined by up-regulation of the lineage markers.
Conclusion: The activated state of mDCs and pDCs seen among diabetes subjects might be due to the increased
levels of GM-CSF and other pro-inflammatory cytokines
Lepton Flavor Violation and the Origin of the Seesaw Mechanism
The right--handed neutrino mass matrix that is central to the understanding
of small neutrino masses via the seesaw mechanism can arise either (i) from
renormalizable operators or (ii) from nonrenormalizable or super-renormalizable
operators, depending on the symmetries and the Higgs content of the theory
beyond the Standard Model. In this paper, we study lepton flavor violating
(LFV) effects in the first class of seesaw models wherein the \nu_R Majorana
masses arise from renormalizable Yukawa couplings involving a B-L = 2 Higgs
field. We present detailed predictions for \tau -> \mu + \gamma and \mu -> e +
\gamma branching ratios in these models taking the current neutrino oscillation
data into account. Focusing on minimal supergravity models, we find that for a
large range of MSSM parameters suggested by the relic abundance of neutralino
dark matter and that is consistent with Higgs boson mass and other constraints,
these radiative decays are in the range accessible to planned experiments. We
compare these predictions with lepton flavor violation in the second class of
models arising entirely from the Dirac Yukawa couplings. We study the
dependence of the ratio r \equiv B(\mu -> e+\gamma)/B(\tau ->\mu +\gamma) on
the MSSM parameters and show that measurement of r can provide crucial insight
into the origin of the seesaw mechanism.Comment: 20 pages, Revtex, 7 figure
Constraining Proton Lifetime in SO(10) with Stabilized Doublet-Triplet Splitting
We present a class of realistic unified models based on supersymmetric SO(10)
wherein issues related to natural doublet-triplet (DT) splitting are fully
resolved. Using a minimal set of low dimensional Higgs fields which includes a
single adjoint, we show that the Dimopoulos--Wilzcek mechanism for DT splitting
can be made stable in the presence of all higher order operators without having
pseudo-Goldstone bosons and flat directions. The \mu term of order TeV is found
to be naturally induced. A Z_2-assisted anomalous U(1)_A gauge symmetry plays a
crucial role in achieving these results. The threshold corrections to
alpha_3(M_Z), somewhat surprisingly, are found to be controlled by only a few
effective parameters. This leads to a very predictive scenario for proton
decay. As a novel feature, we find an interesting correlation between the d=6
(p\to e^+\pi^0) and d=5 (p\to \nu-bar K+) decay amplitudes which allows us to
derive a constrained upper limit on the inverse rate of the e^+\pi^0 mode. Our
results show that both modes should be observed with an improvement in the
current sensitivity by about a factor of five to ten.Comment: 21 pages LaTeX, 2 figures, Few explanatory sentences and three new
references added, minor typos corrected
Finger Ridge Count Correlations Among Four Tribes of Andhra Pradesh, India
The present paper reports the distribution of finger ridge count correlations among
four tribal populations from Andhra Pradesh, India viz., Dulia, Kotia, Manne Dora
and Manzai Mali, and examines the intra and inter population variation. Higher correlations
are recorded in left hands compared to right hands, but they are not significant.
The homologous fingers exhibit a stronger correlation. In all the tribes, the correlations
between right hand fingers are relatively higher among women when compared to men.
Regarding inter population variation Dulia men differ significantly from the men of
Manne Dora and the Manzai Mali tribes, and Kotia women also differ from the women
of the Manne Dora significantly. The average correlation coefficient of the present populations
is similar to other Indian populations reported earlier but lower than African
and European populations
The effects of breath-holding on pulmonary regurgitation measured by cardiovascular magnetic resonance velocity mapping
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