6,124 research outputs found
Detach and Adapt: Learning Cross-Domain Disentangled Deep Representation
While representation learning aims to derive interpretable features for
describing visual data, representation disentanglement further results in such
features so that particular image attributes can be identified and manipulated.
However, one cannot easily address this task without observing ground truth
annotation for the training data. To address this problem, we propose a novel
deep learning model of Cross-Domain Representation Disentangler (CDRD). By
observing fully annotated source-domain data and unlabeled target-domain data
of interest, our model bridges the information across data domains and
transfers the attribute information accordingly. Thus, cross-domain joint
feature disentanglement and adaptation can be jointly performed. In the
experiments, we provide qualitative results to verify our disentanglement
capability. Moreover, we further confirm that our model can be applied for
solving classification tasks of unsupervised domain adaptation, and performs
favorably against state-of-the-art image disentanglement and translation
methods.Comment: CVPR 2018 Spotligh
Singularity problem in f(R) model with non-minimal coupling
We consider the non-minimal coupling between matter and the geometry in the
f(R) theory. In the new theory which we established, a new scalar has
been defined and we give it a certain stability condition. We intend to take a
closer look at the dark energy oscillating behavior in the de-Sitter universe
and the matter era, from which we derive the oscillating frequency, and the
oscillating condition. More importantly, we present the condition of coupling
form that the singularity can be solved. We discuss several specific coupling
forms, and find logarithmic coupling with an oscillating period in the matter era , can improve singularity in the early
universe. The result of numerical calculation verifies our theoretic
calculation about the oscillating frequency. Considering two toy models, we
find the cosmic evolution in the coupling model is nearly the same as that in
the normal f(R) theory when . We also discuss the local tests of the
non-minimal coupling f(R) model, and show the constraint on the coupling form.Comment: 13 pages, 4 figure
Regulation of neuregulin-mediated acetylcholine receptor synthesis by protein tyrosine phosphatase SHP2
Synapse-specific expression of the nicotinic acetylcholine receptor (AChR) is believed to be mediated by neuregulin, an epidermal growth factor-like trophic factor released by somatic motoneurons at the neuromuscular junction (NMJ). Neuregulin stimulates ErbB2, ErbB3, and ErbB4, members of the ErbB family of receptor tyrosine kinases. SHP2 is a cytoplasmic protein tyrosine phosphatase containing two Src homology 2 domains near its N terminus, and has been shown to be a positive mediator of mitogenic responses to various growth factors. We found that SHP2 interacted with ErbB2 and ErbB3 after neuregulin stimulation of muscle cells. Expression of SHP2 in C2C12 mouse muscle cells attenuated the neuregulin-induced expression of an AChR epsilon-promoter reporter gene, whereas a catalytically inactive SHP2 mutant or a mutant lacking the N-terminal Src homology 2 (SH2) domain enhanced reporter expression, suggesting that SHP2 negatively regulates the neuregulin signaling pathway. In fibroblast cells that express a mutant SHP2 with a targeted deletion of the N-terminal SH2 domain, neuregulin-mediated activation of the Ras/Raf/extracellular signal-regulated kinase cascade was enhanced. Furthermore, we found that SHP2 immunoreactivity colocalized with the staining of alpha-bungarotoxin, a marker of the NMJ. These results demonstrate a negative role of SHP2 in the neuregulin signal that leads to AChR gene expression at the NMJ
2D perovskite stabilized phase-pure formamidinium perovskite solar cells.
Compositional engineering has been used to overcome difficulties in fabricating high-quality phase-pure formamidinium perovskite films together with its ambient instability. However, this comes alongside an undesirable increase in bandgap that sacrifices the device photocurrent. Here we report the fabrication of phase-pure formamidinium-lead tri-iodide perovskite films with excellent optoelectronic quality and stability. Incorporation of 1.67 mol% of 2D phenylethylammonium lead iodide into the precursor solution enables the formation of phase-pure formamidinium perovskite with an order of magnitude enhanced photoluminescence lifetime. The 2D perovskite spontaneously forms at grain boundaries to protect the formamidinium perovskite from moisture and suppress ion migration. A stabilized power conversion efficiency (PCE) of 20.64% (certified stabilized PCE of 19.77%) is achieved with a short-circuit current density exceeding 24 mA cm-2 and an open-circuit voltage of 1.130 V, corresponding to a loss-in-potential of 0.35 V, and significantly enhanced operational stability
First asymmetric synthesis of piperidine alkaloid (-)-morusimic acid D
The first asymmetric synthesis of (-)-morusimic acid D, a 2,3-trans-2,6-cis-2-methyl-6-substituted piperidin-3-ol containing alkaloid is reported. The key steps are the reductive alkylation of N,O-diprotected 3-hydroxyglutarimide, a stepwise reductive alkylation, and an asymmetric aldol-type reaction using a modified Evans chiral auxiliary
Qubitization of Bosons
A binary mapping from Fock space of bosonic state to qubits is given. Based
on the binary mapping, we construte an algorithm of qubitization of bosons with
complexity O(log(N)). As an example, the algorithm of qubitization of bosons in
matrix product state to simulate real time dynamics of Yukawa coupling is
realized. The calculation error bar is estimated by random sampling method.
This proposal may be achieved in superconductivity noisy intermediate--scale
quantum computer not far future.Comment: 7 pages, 4 figure
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