127 research outputs found
The Beam Dynamics And Beam Related Uncertainties In Fermilab Muon G-2 Experiment
The anomaly of the muon magnetic moment, aμ ≡ (g-2)/2, has played an important role in constraining physics beyond the Standard Model for many years. Currently, the Standard Model prediction for aμ is accurate to 0.42 parts per million (ppm). The most recent muon g-2 experiment was done at Brookhaven National Laboratory (BNL) and determined aμ to 0.54 ppm, with a central value that differs from the Standard Model prediction by 3.3-3.6 standard deviations and provides a strong hint of new physics. The Fermilab Muon g-2 Experiment has a goal to measure aμ to unprecedented precision: 0.14 ppm, which could provide an unambiguous answer to the question whether there are new particles and forces that exist in nature. To achieve this goal, several items have been identified to lower the systematic uncertainties. In this work, we focus on the beam dynamics and beam associated uncertainties, which are important and must be better understood. We will discuss the electrostatic quadrupole system, particularly the hardware-related quad plate alignment and the quad extension and readout system. We will review the beam dynamics in the muon storage ring, present discussions on the beam related systematic errors, simulate the 3D electric fields of the electrostatic quadrupoles and examine the beam resonances. We will use a fast rotation analysis to study the muon radial momentum distribution, which provides the key input for evaluating the electric field correction to the measured aμ
Semi-leptonic Decay of Lambda-b in the Standard Model and with New Physics
Heavy quark decays provide a very advantageous investigation to test the
Standard Model (SM). Recently, promising experiments with \textit{b} quark, as
well as the analysis of the huge data sets produced at the B factories, have
led to an increasing study and sensitive measurements of relative \textit{b}
quark decays. In this thesis, I calculate various observables in the
semi-leptonic decay process
both in the SM and in the presence of New Physics (NP) operators with different
Lorentz structures. The results are relevant for the coming measurement of this
semi-leptonic decay at LHC \textit{b} experiment in CERN, and also provide
theoretical predictions to refine the physics beyond the SM.Comment: 38 page, 7 figures. arXiv admin note: text overlap with
arXiv:1502.0723
CGoDial: A Large-Scale Benchmark for Chinese Goal-oriented Dialog Evaluation
Practical dialog systems need to deal with various knowledge sources, noisy
user expressions, and the shortage of annotated data. To better solve the above
problems, we propose CGoDial, new challenging and comprehensive Chinese
benchmark for multi-domain Goal-oriented Dialog evaluation. It contains 96,763
dialog sessions and 574,949 dialog turns totally, covering three datasets with
different knowledge sources: 1) a slot-based dialog (SBD) dataset with
table-formed knowledge, 2) a flow-based dialog (FBD) dataset with tree-formed
knowledge, and a retrieval-based dialog (RBD) dataset with candidate-formed
knowledge. To bridge the gap between academic benchmarks and spoken dialog
scenarios, we either collect data from real conversations or add spoken
features to existing datasets via crowd-sourcing. The proposed experimental
settings include the combinations of training with either the entire training
set or a few-shot training set, and testing with either the standard test set
or a hard test subset, which can assess model capabilities in terms of general
prediction, fast adaptability and reliable robustness.Comment: EMNLP 202
UR4NNV: Neural Network Verification, Under-approximation Reachability Works!
Recently, formal verification of deep neural networks (DNNs) has garnered
considerable attention, and over-approximation based methods have become
popular due to their effectiveness and efficiency. However, these strategies
face challenges in addressing the "unknown dilemma" concerning whether the
exact output region or the introduced approximation error violates the property
in question. To address this, this paper introduces the UR4NNV verification
framework, which utilizes under-approximation reachability analysis for DNN
verification for the first time. UR4NNV focuses on DNNs with Rectified Linear
Unit (ReLU) activations and employs a binary tree branch-based
under-approximation algorithm. In each epoch, UR4NNV under-approximates a
sub-polytope of the reachable set and verifies this polytope against the given
property. Through a trial-and-error approach, UR4NNV effectively falsifies DNN
properties while providing confidence levels when reaching verification epoch
bounds and failing falsifying properties. Experimental comparisons with
existing verification methods demonstrate the effectiveness and efficiency of
UR4NNV, significantly reducing the impact of the "unknown dilemma".Comment: 11 pages, 4 figure
Hydrogen-Rich Saline Attenuates Brain Injury Induced by Cardiopulmonary Bypass and Inhibits Microvascular Endothelial Cell Apoptosis Via the PI3K/Akt/GSK3β Signaling Pathway in Rats
Extracting low energy signals from raw LArTPC waveforms using deep learning techniques -- A proof of concept
We investigate the feasibility of using deep learning techniques, in the form
of a one-dimensional convolutional neural network (1D-CNN), for the extraction
of signals from the raw waveforms produced by the individual channels of liquid
argon time projection chamber (LArTPC) detectors. A minimal generic LArTPC
detector model is developed to generate realistic noise and signal waveforms
used to train and test the 1D-CNN, and evaluate its performance on low-level
signals. We demonstrate that our approach overcomes the inherent shortcomings
of traditional cut-based methods by extending sensitivity to signals with ADC
values below their imposed thresholds. This approach exhibits great promise in
enhancing the capabilities of future generation neutrino experiments like DUNE
to carry out their low-energy neutrino physics programs
Effect of vitamin C on intestinal flora disorders in Cr(VI)-contaminated mice
BackgroundHexavalent chromium [Cr(VI)] exposure can cause structural disruption of intestinal flora and functional impairment. Vitamin C (VC) is one of the essential micronutrients, which plays an important role in promoting the growth of intestinal probiotics, improving the intestinal barrier, and maintaining the homeostasis of intestinal flora. However, the regulatory effect of VC on the intestinal flora disorders caused by Cr(VI) exposure remains to be investigated. ObjectiveTo investigate the effect of VC on intestinal flora disruption in mice due to Cr(VI) exposure. MethodsThirty-two SPF-grade C57BL/6 mice were acclimatized and fed for 3 d and randomly divided into control (Con), VC, potassium dichromate [K2Cr2O7, Cr(VI)], and VC+K2Cr2O7 [VC+Cr(VI)] groups. At 8:00 a.m. on day 4, the Con group (double-distilled water given by gavage and injected intraperitoneally), the VC group (VC given by gavage and double-distilled water injected intraperitoneally), the Cr(VI) group (double-distilled water given by gavage and K2Cr2O7 solution injected intraperitoneally), and the VC+Cr(VI) group (VC given by gavage and K2Cr2O7 solution injected intraperitoneally) were treated. The dose of VC was 200 mg·kg−1, and the dose of K2Cr2O7 was 1.25 mg·kg−1. The mice were treated for 45 consecutive days and then executed, the contents of the colon were sampled in sterile freezing tubes, and three replicates were collected from each group. After labeling, the samples were immediately put into liquid nitrogen for rapid freezing. After all the samples were collected, they were transferred to a -80 ℃ ultra-low temperature refrigerator for storage. Samples of colon contents were analyzed for intestinal flora structure by high-throughput sequencing and bioinformatics software. ResultsThe Cr(VI) exposure resulted in reduced body weight gain values in mice compared to the Con group. Pathological changes occurred in the ileal tissue of mice, with significant inflammatory cell infiltration in the Cr(VI) group and reduced inflammatory cell infiltration in the VC+Cr(VI) group. The number of operational taxonomic units (OTUs) of intestinal flora was altered in the Cr(VI) group of mice. In the α diversity analysis, the mean Sobs index in the Cr(VI) group was 240.333±67.796, the Chao index was 258.173±64.813, and the Ace index was 259.481±66.891, which were significantly lower than those in the Con group (P<0.05), the PD whole tree index in the Cr(VI) group was 27.863±2.399, which was significantly higher than that in the Con group (P<0.05), and the VC intervention significantly reversed the changes of the above indexes due to Cr(VI) exposure (P<0.05). In the β diversity analysis, the principal coordinates analysis (PCoA) results showed a significant separation between the Cr(VI) group and the Con group, and after the VC intervention, there was a retraction of the separation trend and the difference was reduced. The multi-sample similarity dendrogram results showed that the control and the VC groups clustered together first, then with the VC+Cr(VI) group, and finally with the Cr(VI) group. The abundances of Bacteroidetes, Saccharibacteria, and Tenericutes in the intestine of mice in the Cr(VI) group were decreased, and the abundance of Firmicutes was increased; the abundances of Lactobacillus, Alistipes, Bacteroides, and Ruminiclostridium were also increased. Included among these, Bacteroides showed a significantly higher abundance compared to the control mice (P<0.05). Changes in the abundances of phyla and genera of the above mentioned gut microorganisms were reversed after the VC intervention. ConclusionCr(VI) exposure can lead to intestinal damage and disorganization of the intestinal flora structure in mice, while VC intervention can ameliorate the above changes to a certain extent and normalize the intestinal flora structure
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