346 research outputs found
Broadband converging plasmon resonance at a conical nanotip
We propose an analytical theory which predicts that Converging
Plasmon Resonance (CPR) at conical nanotips exhibits a red-shifted and
continuous band of resonant frequencies and suggests potential application
of conical nanotips in various fields, such as plasmonic solar cells,
photothermal therapy, tip-enhanced Raman and other spectroscopies. The
CPR modes exhibit superior confinement and ten times broader scattering
bandwidth over the entire solar spectrum than smooth nano-structures. The
theory also explicitly connects the optimal angles and resonant optical
frequencies to the material permittivities, with a specific optimum half
angle that depends only on the real permittivity for high-permittivity and
low-loss materials
Cross-correlations mediated by Majorana bound states
We consider the correlated parallel transport through two quantum dots which
are tunnel-coupled to the ends of a semiconductor nanowire where the Majorana
bound states (MBSs) may emerge under proper conditions. In terms of the
cross-correlation of currents, we reveal unusual behaviors originated from the
nonlocal MBSs, including such as the distinct symmetry and antisymmetry of the
spectral density in response to the dot-level modulations, and the vanished
cross correlation occurred when any of the dot-levels is in resonance with the
Majorana zero mode
TransNFCM: Translation-Based Neural Fashion Compatibility Modeling
Identifying mix-and-match relationships between fashion items is an urgent
task in a fashion e-commerce recommender system. It will significantly enhance
user experience and satisfaction. However, due to the challenges of inferring
the rich yet complicated set of compatibility patterns in a large e-commerce
corpus of fashion items, this task is still underexplored. Inspired by the
recent advances in multi-relational knowledge representation learning and deep
neural networks, this paper proposes a novel Translation-based Neural Fashion
Compatibility Modeling (TransNFCM) framework, which jointly optimizes fashion
item embeddings and category-specific complementary relations in a unified
space via an end-to-end learning manner. TransNFCM places items in a unified
embedding space where a category-specific relation (category-comp-category) is
modeled as a vector translation operating on the embeddings of compatible items
from the corresponding categories. By this way, we not only capture the
specific notion of compatibility conditioned on a specific pair of
complementary categories, but also preserve the global notion of compatibility.
We also design a deep fashion item encoder which exploits the complementary
characteristic of visual and textual features to represent the fashion
products. To the best of our knowledge, this is the first work that uses
category-specific complementary relations to model the category-aware
compatibility between items in a translation-based embedding space. Extensive
experiments demonstrate the effectiveness of TransNFCM over the
state-of-the-arts on two real-world datasets.Comment: Accepted in AAAI 2019 conferenc
Demonstrating nonlocality induced teleportation through Majorana bound states in a semiconductor nanowire
It was predicted by Tewari [Phys. Rev. Lett. {\bf 100}, 027001 (2008)] that a
teleportationlike electron transfer phenomenon is one of the novel consequences
of the existence of Majorana fermion, because of the inherently nonlocal
nature. In this work we consider a concrete realization and measurement scheme
for this interesting behavior, based on a setup consisting of a pair of quantum
dots which are tunnel-coupled to a semiconductor nanowire and are jointly
measured by two point-contact detectors. We analyze the teleportation dynamics
in the presence of measurement backaction and discuss how the teleportation
events can be identified from the current trajectories of strong response
detectors.Comment: 5 pages, 3 figure
The Hedgehog pathway: role in cell differentiation, polarity and proliferation.
Hedgehog (Hh) is first described as a genetic mutation that has "spiked" phenotype in the cuticles of Drosophila in later 1970s. Since then, Hh signaling has been implicated in regulation of differentiation, proliferation, tissue polarity, stem cell population and carcinogenesis. The first link of Hh signaling to cancer was established through discovery of genetic mutations of Hh receptor gene PTCH1 being responsible for Gorlin syndrome in 1996. It was later shown that Hh signaling is associated with many types of cancer, including skin, leukemia, lung, brain and gastrointestinal cancers. Another important milestone for the Hh research field is the FDA approval for the clinical use of Hh inhibitor Erivedge/Vismodegib for treatment of locally advanced and metastatic basal cell carcinomas. However, recent clinical trials of Hh signaling inhibitors in pancreatic, colon and ovarian cancer all failed, indicating a real need for further understanding of Hh signaling in cancer. In this review, we will summarize recent progress in the Hh signaling mechanism and its role in human cancer
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