2,633 research outputs found
Spectral Normalized Dual Contrastive Regularization for Image-to-Image Translation
Existing image-to-image (I2I) translation methods achieve state-of-the-art
performance by incorporating the patch-wise contrastive learning into
Generative Adversarial Networks. However, patch-wise contrastive learning only
focuses on the local content similarity but neglects the global structure
constraint, which affects the quality of the generated images. In this paper,
we propose a new unpaired I2I translation framework based on dual contrastive
regularization and spectral normalization, namely SN-DCR. To maintain
consistency of the global structure and texture, we design the dual contrastive
regularization using different deep feature spaces respectively. In order to
improve the global structure information of the generated images, we formulate
a semantically contrastive loss to make the global semantic structure of the
generated images similar to the real images from the target domain in the
semantic feature space. We use Gram Matrices to extract the style of texture
from images. Similarly, we design style contrastive loss to improve the global
texture information of the generated images. Moreover, to enhance the stability
of model, we employ the spectral normalized convolutional network in the design
of our generator. We conduct the comprehensive experiments to evaluate the
effectiveness of SN-DCR, and the results prove that our method achieves SOTA in
multiple tasks
Multi-crop Contrastive Learning for Unsupervised Image-to-Image Translation
Recently, image-to-image translation methods based on contrastive learning
achieved state-of-the-art results in many tasks. However, the negatives are
sampled from the input feature spaces in the previous work, which makes the
negatives lack diversity. Moreover, in the latent space of the embedings,the
previous methods ignore domain consistency between the generated image and the
real images of target domain. In this paper, we propose a novel contrastive
learning framework for unpaired image-to-image translation, called MCCUT. We
utilize the multi-crop views to generate the negatives via the center-crop and
the random-crop, which can improve the diversity of negatives and meanwhile
increase the quality of negatives. To constrain the embedings in the deep
feature space,, we formulate a new domain consistency loss function, which
encourages the generated images to be close to the real images in the embedding
space of same domain. Furthermore, we present a dual coordinate channel
attention network by embedding positional information into SENet, which called
DCSE module. We employ the DCSE module in the design of generator, which makes
the generator pays more attention to channels with greater weight. In many
image-to-image translation tasks, our method achieves state-of-the-art results,
and the advantages of our method have been proved through extensive comparison
experiments and ablation research
N′-(5-ethoxycarbonyl-3,4-dimethyl-pyrrol-2-yl-methylidene)-4-hydroxybenzohydrazide monohydrate, C17H21N3O5
Abstract
C17H21N3O5, monoclinic, P21/n (no. 14), a = 9.2278(16) Å, b = 15.093(3) Å, c = 12.698(2) Å, β = 105.195(12)°, V = 1706.7(5) Å3, Z = 4, R
gt(F) = 0.0553, wR
ref(F
2) = 0.1662, T = 296 K
2-Chloro-5-chloroÂmethÂyl-1,3-thiaÂzole
In the title compound, C4H3Cl2NS, the chloroÂmethyl C and 2-position Cl atoms lie close to the mean plane of the thiaÂzole ring [deviations = 0.0568 (2) and 0.0092 (1) Å, respectively]. No classical hydrogen bonds are found in the crystal structure
Identification of metabolites of gardenin A in rat liver microsomes using ultra-high performance liquid chromatography coupled with linear ion-trap Orbitrap mass spectrometry
Purpose: To identify the metabolites of gardenin A (GA) in rat liver microsomes (RLMs) using ultra-high performance liquid chromatography coupled with linear ion-trap Orbitrap mass spectrometry (UHPLCLTQ- Orbitrap).Methods: The sample was prepared by incubating GA (100 μg/mL) with RLMs (0.5 mg/mL) for 8 h. Then 5 μL of the sample was injected into UHPLC-LTQ- orbitrap mass spectrometer. The metabolites of GA were tentatively identified based on accurate mass measurements, fragmentation patterns, chromatographic retention times, and bibliography data.Results: A total of 12 metabolites were detected and identified. Based on their structures, the main reactions in the metabolism of GA are de-methoxylation and de-methylation.Conclusion: This is the first report on in vitro metabolites of GA. These results are considered very helpful for better comprehension of the metabolism of GA and its pharmacological effects.Keywords: Gardenin A, Metabolites, UHPLC-LTQ-Orbitrap, Rat Liver microsome
Cosmological Constraints on the Modified Entropic Force Model
Very recently, Verlinde considered a theory in which space is emergent
through a holographic scenario, and proposed that gravity can be explained as
an entropic force caused by changes in the information associated with the
positions of material bodies. Then, motivated by the Debye model in
thermodynamics which is very successful in very low temperatures, Gao modified
the entropic force scenario. The modified entropic force (MEF) model is in fact
a modified gravity model, and the universe can be accelerated without dark
energy. In the present work, we consider the cosmological constraints on the
MEF model, and successfully constrain the model parameters to a narrow range.
We also discuss many other issues of the MEF model. In particular, we clearly
reveal the implicit root to accelerate the universe in the MEF model.Comment: 16 pages, 7 figures, revtex4; v2: discussions added, Phys. Lett. B in
press; v3: published versio
Silencing of c-Ski augments TGF-b1-induced epithelial-mesenchymal transition in cardiomyocyte H9C2 cells
Background: The shRNA lentiviral vector was constructed to silence c-Ski expression in cardiac mus-Â
cle cells, with the aim of exploring the role of c-Ski in transforming growth factor b1 (TGF-b1)-induced epithelial-mesenchymal transitions (EMT) in H9C2 cells. Methods: Real-time polymerase chain reaction (RT-PCR) and western blot were used to detect c-Ski ex- pression at protein and messenger ribonucleic acid (mRNA) levels in 5 different cell lines. Then, lentiviral vector was constructed to silence or overexpress c-Ski in H9C2 cells. MTT and/or soft agar assay and tran- swell assay were used to detect cell proliferation and migration, respectively. The expression levels of c-Ski under different concentrations of TGF-b1 stimulation were detected by RT-qPCR and immunocytochemi- cal analysis. In the presence or absence of TGF-b1 stimulation, the proteins’ expression levels of a-SMA, FN and E-cadherin, which are closely correlated with the process of EMT, were measured by western blot after c-Ski silencing or overexpression. Meanwhile, the effect of c-Ski on Samd3 phosphorylation with TGF-b1 stimulation was investigated.Â
Results: There is a high expression of c-Ski at protein and mRNA levels in H9C2 cell line, which first demonstrated the presence of c-Ski expression in H9C2 cells. Overexpression of c-Ski significantly increased H9C2 cell proliferation. The ability of c-Ski gene silencing to suppress cell proliferation was gradually enhanced, and inhibition efficiency was the highest after 6 to 7 d of transfection. Moreover, H9C2 cells with c-Ski knockdown gained significantly aggressive invasive potential when compared with the control group. TGF-b1 stimulation could dose-independently reduce c-Ski expression in H9C2 cells and lead to obvious down-regulated expression of E-cadherin. Interestingly, c-Ski could restore E-cadherin expression while suppressing a-SMA and/or FN expression stimulated by TGF-b1. How- ever, shRNA-induced c-Ski knockdown aggravated only the TGF-b1-induced EMT. Moreover, c-Ski- -shRNA also promoted the phosphorylation of Samd3 induced by TGF-b1.Â
Conclusions: c-Ski expression in cardiac muscle cells could be down-regulated by TGF-b1. Silencing of c-Ski gene was accompanied by down-regulation of E-cadherin, up-regulation of a-SMA and/or FN and Smad3 phosphorylation induced by TGF-b1, promoting EMT process. Therefore, c-Ski may be closely associated with TGF-b1-induced EMT and play an important role in cardiac fibrosis develop- ment and progression.
Isospin dependence of projectile-like fragment production at intermediate energies
The cross sections of fragments produced in 140 MeV Ca + Be
and Ni + Be reactions are calculated by the statistical
abration-ablation(SAA) model and compared to the experimental results measured
at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State
University. The fragment isotopic and isotonic cross section distributions of
Ca and Ca, Ni and Ni, Ca and Ni, and
Ca and Ni are compared and the isospin dependence of the
projectile fragmentation is studied. It is found that the isospin dependence
decreases and disappears in the central collisions. The shapes of the fragment
isotopic and isotonic cross section distributions are found to be very similar
for symmetric projectile nuclei. The shapes of the fragment isotopic and
isotonic distributions of different asymmetric projectiles produced in
peripheral reactions are found very similar. The similarity of the
distributions are related to the similar proton and neutron density
distributions inside the nucleus in framework of the SAA model.Comment: 7 pages, 4 figures; to be published in Phys Rev
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