1,347 research outputs found
Some aspects of global Lambda polarization in heavy-ion collisions
Large orbital angular momentum can be generated in non-central heavy-ion
collisions, and part of it is expected to be converted into final particle's
polarization due to the spin-orbit coupling. Within the framework of A
Multi-Phase Transport (AMPT) model, we studied the vorticity-induced
polarization of hyperons at the midrapidity region in
Au-Au collisions at energies GeV. Our results show
that the global polarization decreases with the collisional energies and is
consistent with the recent STAR measurements. This behavior can be understood
by less asymmetry of participant matter in the midrapidity region due to faster
expansion of fireball at higher energies. As another evidence, we discuss how
much the angular momentum is deposited in different rapidity region. The result
supports our asymmetry argument.Comment: 6 pages, 4 figures, CPOD 2017 proceedin
CONSTRUCTION OF SHARED TEACHING RESOURCE PLATFORM JOINTLY BUILT BY SCHOOLS AND ENTERPRISES FROM THE PERSPECTIVE OF POSITIVE PSYCHOLOGY
QuantumFed: A Federated Learning Framework for Collaborative Quantum Training
With the fast development of quantum computing and deep learning, quantum
neural networks have attracted great attention recently. By leveraging the
power of quantum computing, deep neural networks can potentially overcome
computational power limitations in classic machine learning. However, when
multiple quantum machines wish to train a global model using the local data on
each machine, it may be very difficult to copy the data into one machine and
train the model. Therefore, a collaborative quantum neural network framework is
necessary. In this article, we borrow the core idea of federated learning to
propose QuantumFed, a quantum federated learning framework to have multiple
quantum nodes with local quantum data train a mode together. Our experiments
show the feasibility and robustness of our framework
CONSTRUCTION OF SHARED TEACHING RESOURCE PLATFORM JOINTLY BUILT BY SCHOOLS AND ENTERPRISES FROM THE PERSPECTIVE OF POSITIVE PSYCHOLOGY
Influence of non-steroidal anti-inflammatory drugs on the inflammatory sonographic features in erosive hand osteoarthritis : an intervention study
Objective The aim was to examine whether inflammatory US features in erosive hand OA patients change when discontinuing intake of NSAIDs before US examination in a non-randomized study.
Methods Patients (n = 99) were allocated to the NSAIDs or control group according to their intake at baseline. US was performed at baseline (T0) and 2 weeks after discontinuation of NSAIDs (T1). Inflammatory features (i.e. synovial proliferation, effusion and power Doppler signal) were scored using a semi-quantitative scale (from zero to three). Pain levels were scored on a numerical rating scale. Binomial mixed models were fitted for US features, and odds ratios of having a US score of at least two vs at most one for synovial proliferation and effusion, and zero vs at least one for power Doppler were calculated.
Results At baseline, both groups [NSAIDs group (n = 47) vs control group (n = 52)] were comparable for numerical rating scale pain, disease duration, number of radiographically affected joints, BMI and US baseline data, but not for age (P = 0.005). At T1, more synovial proliferation and power Doppler signal was seen compared with T0 in the NSAIDs group (P = 0.018 and 0.031, respectively). However, the interaction term time*NSAIDs was not found to be significant for any variable. The numerical rating scale pain at T1 was higher compared with baseline, although statistically non-significant.
Conclusion No significant changes in inflammatory US features were seen in patients with erosive hand OA after withdrawal of NSAIDs for 2 weeks. This study suggests that an NSAID-free period is not necessary before assessing inflammatory disease activity in erosive hand OA
An improved approach for the segmentation of starch granules in microscopic images
<p>Abstract</p> <p>Background</p> <p>Starches are the main storage polysaccharides in plants and are distributed widely throughout plants including seeds, roots, tubers, leaves, stems and so on. Currently, microscopic observation is one of the most important ways to investigate and analyze the structure of starches. The position, shape, and size of the starch granules are the main measurements for quantitative analysis. In order to obtain these measurements, segmentation of starch granules from the background is very important. However, automatic segmentation of starch granules is still a challenging task because of the limitation of imaging condition and the complex scenarios of overlapping granules.</p> <p>Results</p> <p>We propose a novel method to segment starch granules in microscopic images. In the proposed method, we first separate starch granules from background using automatic thresholding and then roughly segment the image using watershed algorithm. In order to reduce the oversegmentation in watershed algorithm, we use the roundness of each segment, and analyze the gradient vector field to find the critical points so as to identify oversegments. After oversegments are found, we extract the features, such as the position and intensity of the oversegments, and use fuzzy c-means clustering to merge the oversegments to the objects with similar features. Experimental results demonstrate that the proposed method can alleviate oversegmentation of watershed segmentation algorithm successfully.</p> <p>Conclusions</p> <p>We present a new scheme for starch granules segmentation. The proposed scheme aims to alleviate the oversegmentation in watershed algorithm. We use the shape information and critical points of gradient vector flow (GVF) of starch granules to identify oversegments, and use fuzzy c-mean clustering based on prior knowledge to merge these oversegments to the objects. Experimental results on twenty microscopic starch images demonstrate the effectiveness of the proposed scheme.</p
Division of labor, skill complementarity, and heterophily in socioeconomic networks
Constituents of complex systems interact with each other and self-organize to
form complex networks. Empirical results show that the link formation process
of many real networks follows either the global principle of popularity or the
local principle of similarity or a tradeoff between the two. In particular, it
has been shown that in social networks individuals exhibit significant
homophily when choosing their collaborators. We demonstrate, however, that in
populations in which there is a division of labor, skill complementarity is an
important factor in the formation of socioeconomic networks and an individual's
choice of collaborators is strongly affected by heterophily. We analyze 124
evolving virtual worlds of a popular "massively multiplayer online role-playing
game" (MMORPG) in which people belong to three different professions and are
allowed to work and interact with each other in a somewhat realistic manner. We
find evidence of heterophily in the formation of collaboration networks, where
people prefer to forge social ties with people who have professions different
from their own. We then construct an economic model to quantify the heterophily
by assuming that individuals in socioeconomic systems choose collaborators that
are of maximum utility. The results of model calibration confirm the presence
of heterophily. Both empirical analysis and model calibration show that the
heterophilous feature is persistent along the evolution of virtual worlds. We
also find that the degree of complementarity in virtual societies is positively
correlated with their economic output. Our work sheds new light on the
scientific research utility of virtual worlds for studying human behaviors in
complex socioeconomic systems.Comment: 14 Latex pages + 3 figure
Fragments of asthenosphere incorporated in the lithospheric mantle underneath the Subei Basin, eastern China: Constraints from geothermobarometric results and water contents of peridotite xenoliths in Cenozoic basalts
Anhydrous, medium/coarse-grained spinel bearing mantle xenoliths from the Subei Basin, Eastern China have mineral arrangements that reflect low energy geometry. Because of clinopyroxene modal contents, they are grouped into cpx-rich lherzolites (cpx ≥ 14percentage), lherzolites (8 5My, based on modelled H2O solid-solid diffusion rate) the occurrence of the last melting episode. Keywords: Water contents, Fertile mantle, Melting models, Water diffusion, Asthenosphere/lithospher
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