44 research outputs found
Spatio-Temporal Patterns of Water Table and Vegetation Status of a Deserted Area
Understanding groundwater-vegetation interactions is crucial for sustaining fragile environments of desert areas such as the Horqin Sandy Land (HSL) in northern China. This study examined spatio-temporal variations in the water table and the associated vegetation status of a 9.71 km2 area that contains meadowland, sandy dunes, and intermediate transitional zones. The depth of the water table and hydrometeorologic parameters were monitored and Landsat Thematic Mapper (TM) and Moderate Resolution Imaging Spectroradiometer (MODIS) data were utilized to assess the vegetation cover. Spatio-temporal variations over the six-year study period were examined and descriptive groundwater-vegetation associations developed by overlaying a water table depth map onto a vegetation index map derived from MODIS. The results indicate that the water table depends on the local topography, localized geological settings, and human activities such as reclamation, with fluctuations occurring at annual and monthly scales as a function of precipitation and potential evapotranspiration. Locations where the water table is closer to the surface tend to have more dense and productive vegetation. The water table depth is more closely associated with vegetative density in meadowlands than in transitional zones, and only poorly associated with vegetation in sandy dunes
Cosmic test of sTGC detector prototype made in China for ATLAS experiment upgrade
Following the Higgs particle discovery, the Large Hadron Collider complex
will be upgraded in several phases allowing the luminosity to increase to . In order to adapt the ATLAS detector to the
higher luminosity environment after the upgrade, part of the ATLAS muon end-cap
system, the Small Wheel, will be replaced by the New Small Wheel. The New Small
Wheel includes two kinds of detectors: small-strip Thin Gap Chambers and
Micromegas. Shandong University, part of the ATLAS collaboration, participates
in the construction of the ATLAS New Small Wheel by developing, producing and
testing the performance of part of the small-strip Thin Gap Chambers. This
paper describes the construction and cosmic-ray testing of small-strip Thin Gap
Chambers in Shandong University
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Reforzando medidas higienicas en la producción de alimentos especializados
This publication is prepared to assist processors of specialty food, distributors, vendors, and food regulators of backgrounds and experience in finding specific information on producing safe specialty food products. This publication discusses the unique characteristics of specialty foods, identifies food safety concerns in specialty foods production, and provides examples of specific control measures for ensuring food safety of specialty food products.Published January 2013. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo
Agonist Anti-GITR Monoclonal Antibody Induces Melanoma Tumor Immunity in Mice by Altering Regulatory T Cell Stability and Intra-Tumor Accumulation
In vivo GITR ligation has previously been shown to augment T-cell-mediated anti-tumor immunity, yet the underlying mechanisms of this activity, particularly its in vivo effects on CD4+ foxp3+ regulatory T cells (Tregs), have not been fully elucidated. In order to translate this immunotherapeutic approach to the clinic it is important gain better understanding of its mechanism(s) of action. Utilizing the agonist anti-GITR monoclonal antibody DTA-1, we found that in vivo GITR ligation modulates regulatory T cells (Tregs) directly during induction of melanoma tumor immunity. As a monotherapy, DTA-1 induced regression of small established B16 melanoma tumors. Although DTA-1 did not alter systemic Treg frequencies nor abrogate the intrinsic suppressive activity of Tregs within the tumor-draining lymph node, intra-tumor Treg accumulation was significantly impaired. This resulted in a greater Teff:Treg ratio and enhanced tumor-specific CD8+ T-cell activity. The decreased intra-tumor Treg accumulation was due both to impaired infiltration, coupled with DTA-1-induced loss of foxp3 expression in intra-tumor Tregs. Histological analysis of B16 tumors grown in Foxp3-GFP mice showed that the majority of GFP+ cells had lost Foxp3 expression. These “unstable” Tregs were absent in IgG-treated tumors and in DTA-1 treated TDLN, demonstrating a tumor-specific effect. Impairment of Treg infiltration was lost if Tregs were GITR−/−, and the protective effects of DTA-1 were reduced in reconstituted RAG1−/− mice if either the Treg or Teff subset were GITR-negative and absent if both were negative. Our results demonstrate that DTA-1 modulates both Teffs and Tregs during effective tumor treatment. The data suggest that DTA-1 prevents intra-tumor Treg accumulation by altering their stability, and as a result of the loss of foxp3 expression, may modify their intra-tumor suppressive capacity. These findings provide further support for the continued development of agonist anti-GITR mAbs as an immunotherapeutic strategy for cancer
A CsI hodoscope on CSHINE for Bremsstrahlung {\gamma}-rays in Heavy Ion Reactions
Bremsstrahlung production in heavy ion reactions at Fermi energies
carries important physical information including the nuclear symmetry energy at
supra-saturation densities. In order to detect the high energy Bremsstrahlung
rays, a hodoscope consisting of 15 CsI(Tl) crystal read out by photo
multiplier tubes has been built, tested and operated in experiment. The
resolution, efficiency and linear response of the units to rays have
been studied using radioactive source and reactions. The
inherent energy resolution of is obtained.
Reconstruction method has been established through Geant 4 simulations,
reproducing the experimental results where comparison can be made. Using the
reconstruction method developed, the whole efficiency of the hodoscope is about
against the emissions at the target position,
exhibiting insignificant dependence on the energy of incident rays
above 20 MeV. The hodoscope is operated in the experiment of Kr +
Sn at 25 MeV/u, and a full energy spectrum up to 80 MeV has
been obtained.Comment: 9 pages, 19 figure
Probing high-momentum component in nucleon momentum distribution by neutron-proton bremsstrahlung {\gamma}-rays in heavy ion reactions
The high momentum tail (HMT) of nucleons, as a signature of the short-range
correlations in nuclei, has been investigated by the high-energy bremsstrahlung
rays produced in Kr + Sn at 25 MeV/u. The energetic
photons are measured by a CsI(Tl) hodoscope mounted on the spectrometer CSHINE.
The energy spectrum above 30 MeV can be reproduced by the IBUU model
calculations incorporating the photon production channel from process in
which the HMTs of nucleons is considered. A non-zero HMT ratio of about
is favored by the data. The effect of the capture channel is
demonstrated
Revisit to the yield ratio of triton and He as an indicator of neutron-rich neck emission
The neutron rich neck zone created in heavy ion reaction is experimentally
probed by the production of the isobars. The energy spectra and angular
distributions of triton and He are measured with the CSHINE detector in
Kr +Pb reactions at 25 MeV/u. While the energy spectrum of
He is harder than that of triton, known as "He-puzzle", the yield
ratio presents a robust rising trend with the polar angle in
laboratory. Using the fission fragments to reconstruct the fission plane, the
enhancement of out-plane is confirmed in comparison to the
in-plane ratios. Transport model simulations reproduce qualitatively the
experimental trends, but the quantitative agreement is not achieved. The
results demonstrate that a neutron rich neck zone is formed in the reactions.
Further studies are called for to understand the clustering and the isospin
dynamics related to neck formation
Aspect of Clusters Correlation at Light Nuclei Excited State
The correlation of was probed via measuring the transverse
momentum and width of one , for the first time,
which represents the spatial and dynamical essentialities of the initial
coupling state in Be nucleus. The weighted interaction vertex of
3 reflected by the magnitudes of their relative momentums and relative
emission angles proves the isosceles triangle configuration for 3 at
the high excited energy analogous Hoyle states.Comment: 8 pages, 9 figure
Variation of Tensor Force due to Nuclear Medium Effect
The enhancement of =3(0) state with isospin excited
by the tensor force in the free Li nucleus has been observed, for the
first time, relative to a shrinkable excitation in the Li cluster
component inside its host nucleus. Comparatively, the excitation of
=0(1) state with isospin for these two Li
formations take on an approximately equal excitation strength. The mechanism of
such tensor force effect was proposed due to the intensive nuclear medium role
on isospin =0 state.Comment: 6 pages, 4 figure
Multi-alpha Boson Gas state in Fusion Evaporation Reaction and Three-body Force
The experimental evidence for the Boson gas state in the
C+CMg fusion evaporation reaction is
presented. By measuring the emission spectrum with multiplicity 2 and
3, we provide insight into the existence of a three-body force among
particles. The observed spectrum exhibited distinct tails corresponding to
particles emitted in pairs and triplets consistent well with the
model-calculations of AV18-UX and chiral effective field theory of NV2-3-la*,
indicating the formation of clusters with three-body force in the
Boson gas state.Comment: 7 pages, 6 figure