327 research outputs found
Habitat suitability and threat analysis of Greater One-horned Rhinoceros Rhinoceros unicornis Linnaeus, 1758 (Mammalia: Perissodactyla: Rhinocerotidae) in Rautahat District, Nepal
The Greater One-horned Rhinoceros Rhinoceros unicornis has been listed as a Vulnerable species on IUCN Red List, Appendix I of CITES, and a protected animal under the National Parks and Wildlife Conservation Act 2029 B.S., 1973. In Nepal, it was found only in Chitwan, Bardia, Shuklaphanta and Parsa national parks, but it has recently been also reported from the forests of Rautahat. The main objectives of the study were to assess habitat suitability and threats for rhinoceros in Rautahat at an elevation range of approximately 300-1,000 m. Remote sensing data and geospatial modeling techniques were used to assess habitat suitability of rhinoceros. Vegetation assessment was carried out for tree, shrubs, and herbs of plot size 10m à 10m, 5m à 5m, 1m à 1m respectively for habitat suitability. Threat analysis was carried out using purposive sampling among local people and their perceptions were collected on the movement of rhinoceros and threats. The integration of nine explanatory variables showed that about 0.06%, 29.18%, 20.45%, and 50.31% of the study area was found to be most suitable, suitable, moderately suitable and unsuitable habitat respectively for rhinoceros. Out of 30 respondents, 37%, 23%, 20%, and 20% identified the main threat to rhinoceros to be unmanaged habitat, poaching, human-wildlife conflict and environmental factors, respectively. This study recommends parts of the Rautahat District to be extended as the habitat of rhinoceros and starting of immediate conservation initiatives in the area. © Rimal et al. 2018.Peer reviewe
Alcohol brand use of youth-appealing advertising and consumption by youth and adults
Background: Youth exposure to alcohol marketing has been shown to be an important contributor to the problem of underage drinking in the U.S. More work is needed on identifying and minimizing content with particular appeal to youth. Design and Methods: We tested the association between the youth-appeal of marketing content of televised alcohol advertisements and the brand-specific alcohol consumption of both underage youth and adults. We used existing data from three sources: a brand-specific alcohol consumption survey among underage youth (N=1032), a brand-specific alcohol consumption survey among adults (N ~13,000), and an analysis of content appealing to youth (CAY) in a sample of televised alcohol advertisements (n=96) aired during the youth survey. The association between CAY scores for the 96 alcohol ads and youth (age 13-20) versus adult (age 21+) consumption of those adsâ brands was tested through bivariate and multivariate models. Results: Brand CAY scores were (a) positively associated with brand-specific youth consumption after controlling for adult brand consumption; (b) positively associated with a ratio of youth-toadult brand-specific consumption; and (c) not associated with adult brand consumption. Conclusions: Alcohol brands with youth-appealing advertising are consumed more often by youth than adults, indicating that these ads may be more persuasive to relatively younger audiences, and that youth are not simply mirroring adult consumption patterns in their choice of brands. Future research should consider the content of alcohol advertising when testing marketing effects on youth drinking, and surveillance efforts might focus on brands popular among youth
A comparison of forward and backward pp pair knockout in 3He(e,e'pp)n
Measuring nucleon-nucleon Short Range Correlations (SRC) has been a goal of
the nuclear physics community for many years. They are an important part of the
nuclear wavefunction, accounting for almost all of the high-momentum strength.
They are closely related to the EMC effect. While their overall probability has
been measured, measuring their momentum distributions is more difficult. In
order to determine the best configuration for studying SRC momentum
distributions, we measured the He reaction, looking at events
with high momentum protons ( GeV/c) and a low momentum neutron
( GeV/c). We examined two angular configurations: either both protons
emitted forward or one proton emitted forward and one backward (with respect to
the momentum transfer, ). The measured relative momentum distribution
of the events with one forward and one backward proton was much closer to the
calculated initial-state relative momentum distribution, indicating that
this is the preferred configuration for measuring SRC.Comment: 8 pages, 9 figures, submitted to Phys Rev C. Version 2 incorporates
minor corrections in response to referee comment
Reducing model bias in a deep learning classifier using domain adversarial neural networks in the MINERvA experiment
We present a simulation-based study using deep convolutional neural networks
(DCNNs) to identify neutrino interaction vertices in the MINERvA passive
targets region, and illustrate the application of domain adversarial neural
networks (DANNs) in this context. DANNs are designed to be trained in one
domain (simulated data) but tested in a second domain (physics data) and
utilize unlabeled data from the second domain so that during training only
features which are unable to discriminate between the domains are promoted.
MINERvA is a neutrino-nucleus scattering experiment using the NuMI beamline at
Fermilab. -dependent cross sections are an important part of the physics
program, and these measurements require vertex finding in complicated events.
To illustrate the impact of the DANN we used a modified set of simulation in
place of physics data during the training of the DANN and then used the label
of the modified simulation during the evaluation of the DANN. We find that deep
learning based methods offer significant advantages over our prior track-based
reconstruction for the task of vertex finding, and that DANNs are able to
improve the performance of deep networks by leveraging available unlabeled data
and by mitigating network performance degradation rooted in biases in the
physics models used for training.Comment: 41 page
Measurement of Total and Differential Cross Sections of Neutrino and Antineutrino Coherent Production on Carbon
Neutrino induced coherent charged pion production on nuclei,
, is a rare inelastic interaction in
which the four-momentum squared transfered to the nucleus is nearly zero,
leaving it intact. We identify such events in the scintillator of MINERvA by
reconstructing |t| from the final state pion and muon momenta and by removing
events with evidence of energetic nuclear recoil or production of other final
state particles. We measure the total neutrino and antineutrino cross sections
as a function of neutrino energy between 2 and 20 GeV and measure flux
integrated differential cross sections as a function of , and
. The dependence and equality of the neutrino and
anti-neutrino cross-sections at finite provide a confirmation of Adler's
PCAC hypothesis
Measurement of Exclusive Electroproduction Structure Functions and their Relationship to Transversity GPDs
Exclusive electroproduction at a beam energy of 5.75 GeV has been
measured with the Jefferson Lab CLAS spectrometer. Differential cross sections
were measured at more than 1800 kinematic values in , , , and
, in the range from 1.0 to 4.6 GeV,\ up to 2 GeV,
and from 0.1 to 0.58. Structure functions and were extracted as functions of for each of
17 combinations of and . The data were compared directly with two
handbag-based calculations including both longitudinal and transversity GPDs.
Inclusion of only longitudinal GPDs very strongly underestimates and fails to account for and ,
while inclusion of transversity GPDs brings the calculations into substantially
better agreement with the data. There is very strong sensitivity to the
relative contributions of nucleon helicity flip and helicity non-flip
processes. The results confirm that exclusive electroproduction offers
direct experimental access to the transversity GPDs.Comment: 6 pages, 2 figure
Cross sections for the ÎłpâK*+Î and ÎłpâK*+ÎŁ0 reactions measured at CLAS
The first high-statistics cross sections for the reactions ÎłpâK*+Î and ÎłpâK*+ÎŁ0 were measured using the CLAS detector at photon energies between threshold and 3.9 GeV at the Thomas Jefferson National Accelerator Facility. Differential cross sections are presented over the full range of the center-of-mass angles, and then fitted to Legendre polynomials to extract the total cross section. Results for the K*+Î final state are compared with two different calculations in an isobar and a Regge model, respectively. Theoretical calculations significantly underestimate the K*+Î total cross sections between 2.1 and 2.6 GeV, but are in better agreement with present data at higher photon energies
First evidence of coherent meson production in neutrino-nucleus scattering
Neutrino-induced charged-current coherent kaon production,
, is a rare, inelastic electroweak process
that brings a on shell and leaves the target nucleus intact in its ground
state. This process is significantly lower in rate than neutrino-induced
charged-current coherent pion production, because of Cabibbo suppression and a
kinematic suppression due to the larger kaon mass. We search for such events in
the scintillator tracker of MINERvA by observing the final state ,
and no other detector activity, and by using the kinematics of the final state
particles to reconstruct the small momentum transfer to the nucleus, which is a
model-independent characteristic of coherent scattering. We find the first
experimental evidence for the process at significance.Comment: added ancillary file with information about the six kaon candidate
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