632 research outputs found
Storage and retrieval of continuous-variable polarization-entangled cluster states in atomic ensembles
We present a proposal for storing and retrieving a continuous-variable
quadripartite polarization-entangled cluster state, using macroscopic atomic
ensembles in a magnetic field. The Larmor precession of the atomic spins leads
to a symmetry between the atomic canonical operators. In this scheme, each of
the four spatially separated pulses passes twice through the respective
ensemble in order to map the polarization-entangled cluster state onto the
long-lived atomic ensembles. The stored state can then be retrieved by another
four read-out pulses, each crossing the respective ensemble twice. By
calculating the variances, we analyzed the fidelities of the storage and
retrieval, and our scheme is feasible under realistic experimental conditions.Comment: 6 pages, 4 figure
Phase Diagram of Rydberg atoms in a nonequilibrium optical lattice
We study the quantum nonequilibrium dynamics of ultracold three-level atoms
trapped in an optical lattice, which are excited to their Rydberg states via a
two-photon excitation with nonnegligible spontaneous emission. Rich quantum
phases including uniform phase, antiferromagnetic phase and oscillatory phase
are identified. We map out the phase diagram and find these phases can be
controlled by adjusting the ratio of intensity of the pump light to the control
light, and that of two-photon detuning to the Rydberg interaction strength.
When the two-photon detuning is blue-shifted and the latter ratio is less than
1, bistability exists among the phases. Actually, this ratio controls the
Rydberg-blockade and antiblockade effect, thus the phase transition in this
system can be considered as a possible approach to study both effects.Comment: 5 pages,5 figure
Information filtering via preferential diffusion
Recommender systems have shown great potential to address information
overload problem, namely to help users in finding interesting and relevant
objects within a huge information space. Some physical dynamics, including heat
conduction process and mass or energy diffusion on networks, have recently
found applications in personalized recommendation. Most of the previous studies
focus overwhelmingly on recommendation accuracy as the only important factor,
while overlook the significance of diversity and novelty which indeed provide
the vitality of the system. In this paper, we propose a recommendation
algorithm based on the preferential diffusion process on user-object bipartite
network. Numerical analyses on two benchmark datasets, MovieLens and Netflix,
indicate that our method outperforms the state-of-the-art methods.
Specifically, it can not only provide more accurate recommendations, but also
generate more diverse and novel recommendations by accurately recommending
unpopular objects.Comment: 12 pages, 10 figures, 2 table
Geometric quantization of Hamiltonian actions of Lie algebroids and Lie groupoids
We construct Hermitian representations of Lie algebroids and associated
unitary representations of Lie groupoids by a geometric quantization procedure.
For this purpose we introduce a new notion of Hamiltonian Lie algebroid
actions. The first step of our procedure consists of the construction of a
prequantization line bundle. Next, we discuss a version of K\"{a}hler
quantization suitable for this setting. We proceed by defining a
Marsden-Weinstein quotient for our setting and prove a ``quantization commutes
with reduction'' theorem. We explain how our geometric quantization procedure
relates to a possible orbit method for Lie groupoids. Our theory encompasses
the geometric quantization of symplectic manifolds, Hamiltonian Lie algebra
actions, actions of families of Lie groups, foliations, as well as some general
constructions from differential geometry.Comment: 40 pages, corrected version 11-01-200
Ferromagnetism in a lattice of Bose condensates
We show that an ensemble of spinor Bose-Einstein condensates confined in a
one dimensional optical lattice can undergo a ferromagnetic phase transition
and spontaneous magnetization arises due to the magnetic dipole-dipole
interaction. This phenomenon is analogous to ferromagnetism in solid state
physics, but occurs with bosons instead of fermions.Comment: 4 pages, 2 figure
Fragmented Condensate Ground State of Trapped Weakly Interacting Bosons in Two Dimensions
The ground state and its structure for a rotating, harmonically trapped
N-Boson system with a weak repulsive contact interaction are studied as the
angular momentum L increases up to 3N. We show that the ground state is
generally a fragmented condensate due to angular momentum conservation. In
response to an (arbitrarily weak) asymmetric perturbation of the trap, however,
the fragmented ground state can be transformed into a single condensate state.
We manifest this intrinsic instability by calculating the conditional
probability distributions, which show patterns analogous to the boson density
distributions predicted by mean-field theory.Comment: 4 pages, 4 ps figure
Photonic band gaps and defect states induced by excitations of Bose-Einstein condensates in optical lattices
We study the interaction of a Bose-Einstein condensate, which is confined in
an optical lattice, with a largely detuned light field propagating through the
condensate. If the condensate is in its ground state it acts as a periodic
dielectric and gives rise to photonic band gaps at optical frequencies. The
band structure of the combined system of condensed lattice-atoms and photons is
studied by using the concept of polaritons. If elementary excitations of the
condensate are present, they will produce defect states inside the photonic
band gaps. The frequency of localized defect states is calculated using the
Koster-Slater model.Comment: 10 pages, 1 figure, RevTe
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Abstract 4955: Somatic mutation frequency in prostate cancer patients of different ancestries and age of onset
Abstract:
Background::
Prostate cancer (PCa) varies significantly in outcomes based on age of onset and genetic ancestry. Early-onset PCa (EoPCa), diagnosed in men under 55, exhibits aggressive behavior, poor differentiation, and resistance to hormonal therapies, resulting in worse outcomes compared to late-onset PCa (LoPCa). African American (AA) men face more aggressive disease and higher incidence rates than White men with European heritage (EA), even after accounting for socioeconomic factors. Investigating somatic mutations in PCa is essential to understanding disease progression, as the biology of EoPCa remains poorly defined. Comparing mutational frequencies in AA and EA men with EoPCa and LoPCa provides key insights into these disparities and informs targeted interventions.
Methods::
We analyzed the mutational status of EoPCa and LoPCa in AA and EA patients. We isolated DNA in tumor tissue from FFPE prostatectomy tissues using Qiagen’s FFPE DNA Purification Plus Kit. DNA samples from three patients in each cohort (AA LoPCa, AA EoPCa, EA LoPCa, EA EoPCa) were investigated for 81 somatic mutations across 13 genes using real-time PCR. Mutational analysis was performed with Qiagen’s qBiomarker Prostate Cancer Gene Panel, an assay designed to detect PCa specific sequence alterations. DNA and qBiomarker Probe Master Mix were prepared following the manufacturer’s protocol. Relative fold gene expression was calculated using the 2-∆∆Ct (delta-delta Ct) method, with DNA from normal epithelial prostate tissue serving as the control. Values exceeding a threshold of 4 were considered indicative of mutations.
Results::
The analysis of somatic mutation frequencies, with their position and substitution, revealed notable differences across race and the combined factors of race and age of onset. Our analysis revealed higher mutation rates in AA patients for CTNNB1 98 C>T (83.3% AA vs. 66.7% in EA) and KRAS 34 G>A (66.7% AA vs. 33.3% in EA), mutations not previously reported as elevated in AA PCa. When examining race and age of onset together, distinct patterns emerged. Among LoPCa patients, the TP53 827 C>T mutation was found in 100% of AA patients compared to 66.7% of EA patients, while the HRAS 35 G>T mutation was present in 33.3% of AA patients but absent in EA patients. In EoPCa, AA patients exhibited higher frequencies of the CTNNB1 101 G>T mutation (33.3% AA vs. 0% in EA) and KRAS 35 G>C mutation (33.3% AA vs. 0% in EA).
Conclusion::
These mutations, previously unexamined in the context of race and age of onset, highlight disparities in the mutational landscape of PCa.
Citation Format::
Tara S. Jennings, Anton N. Nguyen, Weiping Chu, Dan Mercola, Farah Rahmatpanah. Somatic mutation frequency in prostate cancer patients of different ancestries and age of onset [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 4955
Erythropoietin: A potent inducer of peripheral immuno/inflammatory modulation in autoimmune EAE
Background: Beneficial effects of short-term erythropoietin (EPO) theraphy have been demonstrated in several animal models of acute neurologic injury, including experimental autoimmune encephalomyelitis(EAE)-the animal model of multiple sclerosis. We have found that EPO treatment substantially reduces the acute clinical paralysis seen EAE mice and this improvements is accompanied by a large reduction in the mononuclear cell infiltration and downregulation of glial MHC class II expression within the inflamed CNS. Other reports have recently indicated that peripherally generated anti-inflammatory CD4 +Foxp3 3 regulatory T cells (Tregs) and the IL17-producing CD4+ T helper cell (Th17) subpopulations play key antagonistic roles in EAE pathogenesis. However, no information regardind the effects of EPO theraphy on the behavior of the general mononuclear-lymphocyte population, Tregs or Th17 cells in EAE has emerged. Methods and Findings: We first determined in vivo that EPO theraphy markedly suppressed MOG specific T cell proliferation and sharply reduced the number of reactive dendritic cells (CD11c positive) in EAE lumph modes during both inductive and later symptomatic phases of MOG 35-55 induced EAE. We then determined the effect in vivo of EPO on numbers of peripheral Treg cells and Th17 cells. We found that EPO treatment modulated immune balance in both the periphery and the inflamed spinal cord by promoting a large expansion in Treg cells, inhibiting Th17 polarization and abrogating proliferation of the antigen presenting dendritic cell population. Finally we utilized tissue culture assays to show that exposure to EPO in vitro similarly downregulated MOG-specific T cell proliferation and also greatly suppressed T cell production of pro-inflammatory cytokines. Conclusions: Taken together, our findings reveal an important new locus whereby EPO induces substantial long-term tissue protection in the host through signalling to several critical subsets of immune cells that reside in the peripheral lymphatic system.published_or_final_versio
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