2,099 research outputs found
Unraveling Proton Strangeness: Robust Determination of the Strangeness Sigma Term with High Statistical Significance
This study delves into the contribution of the strange quark within the
proton, which influences several fundamental proton properties. By establishing
a robust relationship between the proton's quantum anomalous energy and the
sigma term, we successfully extract the strangeness sigma term ()
with a precise value of MeV. Additionally, we present novel
results for the proton trace anomalous energy, observing a value of
. Our analysis integrates the most recent data from the Hall C and
GlueX collaborations, warranting a strong endorsement for the existence of a
non-zero strangeness component inside the proton, with a remarkable statistical
significance of . Furthermore, we investigate the possibility of
scheme-independence in the extraction results and examine the uniformity of
sigma terms obtained from the datasets provided by the two collaborations. Our
analysis reveals compatibility between the extraction results of the respective
experiments.Comment: 5 pages, 3 figures, 2 table
Mechanical structures inside proton with configurational entropy language
The structure of the proton remains a significant challenge within the field
of Quantum Chromodynamics, with the origin of its spin and mass still lacking a
satisfactory explanation. In this study, we utilize the gravitational form
factor of the proton as the foundation for constructing the configurational
entropy of the proton energy system. Employing this approach, we are able to
determine key mechanical quantities such as the proton's mass radius and
pressure distribution. Our analysis yields the root-mean-square mass radius of
fm and scalar radius of fm for proton, which are found to be in excellent
agreement with recent measurements from the Hall-C collaboration group at
Jefferson Lab. Additionally, we examine the radial distribution of pressure and
shear force within the proton.Comment: 6 pages, 3 figures and 1 tabl
Exploring Short-Range Correlations in Symmetric Nuclei: Insights into Contacts and Entanglement Entropy
The Short-Range Correlations between nucleons in nuclei is regarded as a
complex system. We investigate the relationship between the orbital
entanglement entropy of SRCs in nuclear structures and Tan contact
, and find that the orbital entanglement entropies and Tan contacts
corresponding to proton-proton SRC pairs and neutron-proton SRC pairs in nuclei
demonstrate a scaling relation. More specifically, the proportionality of
entanglement entropy between proton-proton pairs and neutron-proton pairs is
directly related to the ratio of nuclear contacts within the atomic nucleus,
demonstrating an approximate ratio of 2.0. Our research suggests that this
scaling relationship should hold true for all symmetric nuclei, furthermore, we
offer a possible explanation for this phenomenon.Comment: 8 pages, 5 figures, 1 table, accepted by PL
Trace Anomaly of Proton Mass with Vector Meson Near-Thresholds Photoproduction Data
Trace anomalous contribution to proton mass is particularly important in
understanding the QCD mass structure. The value and the scale-dependent of the
trace anomalous energy of the strong interaction are still not clear in
combination of theories and experiments. In this paper, we explore the
near-threshold photoproduction data of and J/ to study the quantum
anomalous energy in QCD and its scale-dependence. The vector-meson-dominance
model and the van der Waals interaction between the vector meson and the proton
are used. We find that the quantum anomalous energy to the proton mass is
scale-dependent and it can be described as with
GeV. The empirical result is consistent with the LQCD
calculation at GeV. Finally, the corresponding evolution equation
for trace anomaly part is given by our calculation.Comment: 6 pages, 4 figures, Corrected spelling mistake
4,8-Dimethoxyfuro[2,3-b]quinoline (γ-fagarine)
The title molecule, C13H11NO3, a natural compound extracted from Phellodendron chinense, exhibits a near planar framework: the mean deviations from the furo[2,3-b]quinoline ring system and from the whole molecule (not including the H atoms) are 0.006 and 0.062 Å, respectively
Central catecholamine depletion inhibits peripheral lymphocyte proliferation and splenocyte cytokine production
Evidence demonstrating that immune response is under the control of central nervous system has been accumulated during the past two decades. Central catecholamines have been proved to play a pivotal role in modulation of humoral and cellular immunity both in vitro and in vivo. However, the modulation of central catecholamine depletion on peripheral cellular immune response remains somewhat unclear. Therefore, we designed a set of experiments to analyse the influence of central catecholamine depletion by i.c.v. 6-OHDA injection on peripheral cellular immune functions. Two, four and seven days after the injection in rats, they were sacrificed and spleen and blood samples were collected to measure the lymphocyte proliferation, cytokine production and IL-2 mRNA expression. Brain and spleen samples were obtained for catecholamine determination as well. Our data demonstrate that two, four and seven days after i.c.v. 6-OHDA treatment, dopamine, norepinephrine and epinephrine levels in the hypothalamus and in the cortex are significantly reduced. Additionally, norepinephrine and epinephrine concentrations in the spleen are significantly decreased four days after the injection. In contrast, the serotonin levels in the brain and in the spleen are not changed seven days after the central 6-OHDA treatment. More importantly, Con A-induced lymphocyte proliferation and splenocyte cytokine production at both protein (IL-2 and IFN-?) and mRNA (IL-2) levels are significantly reduced seven days after i.c.v. 6-OHDA injection. These results confirm the important role of central catecholamines in modulating peripheral cellular immune response. Although the precise mechanism of how central catecholamine depletion alters peripheral cellular immunity is still not clear, the fact that a significant reduction in splenic catecholamine contents is observed four days after i.c.v. 6-OHDA treatment suggests that peripheral sympathetic nervous system plays a role in these effects
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