681 research outputs found
Associated single photons and doubly charged scalar at linear e-e- colliders
Doubly charged scalars, predicted in many models having exotic Higgs
representations, can in general have lepton-number violating (LFV) couplings.
We show that by using an associated monoenergetic final state photon seen at a
future linear e-e- collider, we can have a clear and distinct signature for a
doubly-charged resonance. The strength of the Delta L=2 coupling can also be
probed quite effectively as a function of the recoil mass of the doubly-charged
scalar.Comment: Reference adde
PrFeO3 Photocathodes Prepared Through Spray Pyrolysis
Perovskite oxides are receiving wide interest for photocatalytic and photoelectrochemical devices, owing to their suitable band gaps for solar light absorption and stability in aqueous applications. Herein, we assess the activity of PrFeO3 photocathodes prepared by using spray pyrolysis and calcination temperatures between 500 and 700â°C. Scanning electron microscopy shows corrugated films of high surface coverage on the conductive glass substrate. The electrochemically active surface area shows slight decreases with temperature increases from 500 to 600 and 700â°C. However, transient photocurrent responses and impedance spectroscopy data showed that films calcined at higher temperatures reduced the probabilities of recombination due to trap states, resulting in faster rates of charge extraction. In this tradeâoff, a calcination temperature of 600â°C provided a maximum photocurrent of â130±4â
ÎŒAâcmâ2 at +0.43â
VRHE under simulated sunlight, with an incident photonâtoâcurrent conversion efficiency of 6.6â% at +0.61â
VRHE and 350â
nm and an onset potential of +1.4â
VRHE for cathodic photocurrent
Jacobi Crossover Ensembles of Random Matrices and Statistics of Transmission Eigenvalues
We study the transition in conductance properties of chaotic mesoscopic
cavities as time-reversal symmetry is broken. We consider the Brownian motion
model for transmission eigenvalues for both types of transitions, viz.,
orthogonal-unitary and symplectic-unitary crossovers depending on the presence
or absence of spin-rotation symmetry of the electron. In both cases the
crossover is governed by a Brownian motion parameter {\tau}, which measures the
extent of time-reversal symmetry breaking. It is shown that the results
obtained correspond to the Jacobi crossover ensembles of random matrices. We
derive the level density and the correlation functions of higher orders for the
transmission eigenvalues. We also obtain the exact expressions for the average
conductance, average shot-noise power and variance of conductance, as functions
of {\tau}, for arbitrary number of modes (channels) in the two leads connected
to the cavity. Moreover, we give the asymptotic result for the variance of
shot-noise power for both the crossovers, the exact results being too long. In
the {\tau} \rightarrow 0 and {\tau} \rightarrow \infty limits the known results
for the orthogonal (or symplectic) and unitary ensembles are reproduced. In the
weak time-reversal symmetry breaking regime our results are shown to be in
agreement with the semiclassical predictions.Comment: 24 pages, 5 figure
Splenectomy for diagnosis of lymphomas: A case series
Splenomegaly can be caused by various etiologies such as infections, congestion/ portal hypertension, auto-immune diseases, infiltrative diseases and malignancy. It requires extensive work-up of hematological, radiological and
sometimes bone marrow studies to arrive at definitive diagnosis. However, in 3-36% of cases, cause of splenomegaly remains unknown despite extensive work up; among which lymphomas (16-44%) are an important cause. Hence splenectomy and pathological examination of the spleen might be the only option in this sub-set of patients to confirm the diagnosis. Here is a series of four cases of splenomegaly of unknown etiology presented to us over a period of 3
years who underwent laparoscopic splenectomy for diagnostic purpose. All these cases were diagnosed as Non-Hodgkin's lymphoma. Thrombocytopenia, anaemia and symptoms due to mass effect that these patients had prior to
surgery were reversed. All patients were started on chemotherapy with-in 4 weeks of surgery
Conductance Distributions in Chaotic Mesoscopic Cavities
We consider the conductance distributions in chaotic mesoscopic cavities for
all three invariant classes of random matrices for the arbitrary number of
channels N1, N2 in the connecting leads. We show that the Laplace transforms of
the distributions can be expressed in terms of determinants in the unitary case
and Pfaffians in the orthogonal and symplectic cases. The inverse Laplace
transforms then give the exact distributions. This formalism is particularly
useful for small values of N = min (N1, N2), and thus is of direct experimental
relevance. We also obtain the conductance distributions for orthogonal-unitary
and symplectic-unitary crossover ensembles.Comment: 19 pages, 4 figure
Field-induced canting of magnetic moments in GdCo5 at finite temperature : first-principles calculations and high-field measurements
We present calculations and experimental measurements of the temperature-dependent magnetization of a single crystal of GdCo5 in magnetic fields of order 60 T. At zero temperature the calculations, based on density-functional theory in the disordered-local-moment picture, predict a field-induced transition from an antiferromagnetic to a canted alignment of Gd and Co moments at 46.1 T. At higher temperatures the calculations find this critical field to increase along with the zerofield magnetization. The experimental measurements observe this transition to occur between 44â48 T at 1.4 K. Up to temperatures of at least 100 K, the experiments continue to observe the transition; however, at variance with the calculations, no strong temperature dependence of the critical field is apparent. We assign this difference to the inaccurate description of the zero-field magnetization of the calculations at low temperatures, due to the use of classical statistical mechanics. Correcting for this effect, we recover a consistent description of the high-field magnetization of GdCo5 from theory and experiment
Anomalous anticrossing of neutral exciton states in GaAs/AlGaAs quantum dots
International audienceWe study the effects of heavy hole-light hole (HH-LH) mixing on fine-structure and polarization properties of neutral excitons ( X-0) confined in single GaAs/AlGaAs quantum dots (QDs) under the application of anisotropic biaxial stress. In the large HH-LH mixing regime, these properties are substantially different from the usually observed properties in the case of small or no mixing. By varying the applied stress, the mixing in the initially strain-free QDs changes from similar to 0 to similar to 70% and an anomalous anticrossing of the X-0 bright states is observed. The latter is attributed to stress-induced rotation of the in-plane principal axis of the QD confinement potential. We show that the analysis of free-excitonic emission of bulk GaAs surrounding the QDs not only allows estimation of the stress and mixing in the QDs, but also provides the quantum-confinement-induced HH-LH splitting of the as-grown QDs
Not Available
Not AvailablePhytic acid (PA) is an important antinutritional
component in maize that affects the availability
of major micro-nutrients like di- and multivalent
mineral cations like iron (Fe) and zinc (Zn).
The long-term consumption of maize as a staple food
crop leads to micronutrient malnutrition especially
iron and zinc deficiency in the human population. In
addition, it also acts as a storehouse of a major part of
mineral phosphorous (P), approximately 80% of the
total P stored as phytate P is not available to monogastric
animals like humans and poultry birds, and it gets excreted as such, leading to one of the major
environmental pollution called eutrophication. Of the
various low phytic acid (lpa) mutants, lpa2-2 generated
through mutagenesis reduces PA by 30%. BML 6
and BML 45, the parents of the popular maize hybrid
DHM 121 with high PA were selected to introgress
lpa2-2 through marker-assisted backcross breeding
(MABB). The percent recurrent parental genome
(RPG) in the selected BC2F2
plants ranged from 88.68
to 91.04% and 90.09â91.51% in the genetic background
of BML 6 and BML 45, respectively. Based
on the highest percentage of RPG, best five BC2F2
plants, viz., #3190, #3283, #3230, #3263 and #3292
with RPG 88.68â91.04% in the genetic background of
BML 6 and #3720, #3776, #3717, #3828 and #3832
with RPG 90.09â91.51% in the genetic background
of BML 45 were advanced to BC2F3.
The newly
developed near-isogenic lines (NILs) possessed low
phytate content (2.37 mg/g in BML 6 and 2.40 mg/g
in BML 45) compared to 3.59 mg/g and 3.16 mg/g in
recurrent parents BML 6 and BML 45, respectively
thereby reducing the phytate by an average of 34 and
24 per cent, respectively. These newly developed
progenies were similar to their recurrent parents for
various morphological traits. These inbreds assume
great significance in alleviating Fe and Zn deficiencies
in worldwide.Not Availabl
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