1,790 research outputs found
Analytical result on the supercurrent through a superconductor/quantum-dot/superconductor junction
We present an analytical result for the supercurrent across a
superconductor/quantum-dot/superconductor junction. By converting the current
integration into a special contour integral, we can express the current as a
sum of the residues of poles. These poles are real and give a natural
definition of the Andreev bound states. We also use the exact result to explain
some features of the supercurrent transport behavior.Comment: 8 pages, 2 figure
Photon-assisted Fano Resonance and Corresponding Shot-Noise in a Quantum Dot
We have studied the Fano resonance in photon-assisted transport in a quantum
dot and calculated both the coherent current and spectral density of shot
noise. It is predicted, for the first time, that the shape of Fano profile will
also appear in satellite peaks. It is found that the variations of Fano
profiles with the strengths of nonresonant transmissions are not synchronous in
absorption and emission sidebands. The effect of interference on
photon-assisted pumped current has been also investigated. We further predict
the current and spectral density of shot noise as a function of the phase,
which exhibits an intrinsic property of resonant and nonresonant channels in
the structures.Comment: 4 pages, 5 figure
Rapid identification of allergenic and pathogenic molds in environmental air by an oligonucleotide array
<p>Abstract</p> <p>Background</p> <p>Airborne fungi play an important role in causing allergy and infections in susceptible people. Identification of these fungi, based on morphological characteristics, is time-consuming, expertise-demanding, and could be inaccurate.</p> <p>Methods</p> <p>We developed an oligonucleotide array that could accurately identify 21 important airborne fungi (13 genera) that may cause adverse health problems. The method consisted of PCR amplification of the internal transcribed spacer (ITS) regions, hybridization of the PCR products to a panel of oligonucleotide probes immobilized on a nylon membrane, and detection of the hybridization signals with alkaline phosphatase-conjugated antibodies.</p> <p>Results</p> <p>A collection of 72 target and 66 nontarget reference strains were analyzed by the array. Both the sensitivity and specificity of the array were 100%, and the detection limit was 10 pg of genomic DNA per assay. Furthermore, 70 fungal isolates recovered from air samples were identified by the array and the identification results were confirmed by sequencing of the ITS and D1/D2 domain of the large-subunit RNA gene. The sensitivity and specificity of the array for identification of the air isolates was 100% (26/26) and 97.7% (43/44), respectively.</p> <p>Conclusions</p> <p>Identification of airborne fungi by the array was cheap and accurate. The current array may contribute to decipher the relationship between airborne fungi and adverse health effect.</p
Remaining As A Leader or Not? Technology Spillover Answers
Much has been discussed about the advantages and disadvantages of being a first mover. However, discussion regarding the incentives encouraging a firm to remain as leader is absent in most studies. This paper aims to fill this gap and provide theoretical and empirical evidences vis-à-vis the incentives of remaining as a leader, by comparing profits between leader and follower when taking technology spillover and technological efficiency into consideration. The findings show that in regard to effective technological efficiency: (i) under the condition of a weak (strong) technology spillover, retaining the position of leader firm is (not) a dominant strategy because of higher (lower) profits than a follower; (ii) the half-shared technology spillover leads to an equal profit between firms, and implies a critical time of action for the leader firm to break the evenly-matched status by reconsidering first mover advantages; (iii) an empirical study on a data set of 352 high-tech and non-high-tech SMEs in manufacturing industry from 1999 until 2006 lends strong support to these results and may also provide useful clues for technology managers or practitioners to make better policies to benefit their market competitiveness
Single Image Texture Translation for Data Augmentation
Recent advances in image synthesis enables one to translate images by
learning the mapping between a source domain and a target domain. Existing
methods tend to learn the distributions by training a model on a variety of
datasets, with results evaluated largely in a subjective manner. Relatively few
works in this area, however, study the potential use of semantic image
translation methods for image recognition tasks. In this paper, we explore the
use of Single Image Texture Translation (SITT) for data augmentation. We first
propose a lightweight model for translating texture to images based on a single
input of source texture, allowing for fast training and testing. Based on SITT,
we then explore the use of augmented data in long-tailed and few-shot image
classification tasks. We find the proposed method is capable of translating
input data into a target domain, leading to consistent improved image
recognition performance. Finally, we examine how SITT and related image
translation methods can provide a basis for a data-efficient, augmentation
engineering approach to model training
Electron dephasing in homogeneous and inhomogeneous indium tin oxide thin films
The electron dephasing processes in two-dimensional homogeneous and
inhomogeneous indium tin oxide thin films have been investigated in a wide
temperature range 0.3--90 K. We found that the small-energy-transfer
electron-electron (-) scattering process dominated the dephasing from a
few K to several tens K. At higher temperatures, a crossover to the
large-energy-transfer - scattering process was observed. Below about 1--2
K, the dephasing time revealed a very weak temperature
dependence, which intriguingly scaled approximately with the inverse of the
electron diffusion constant , i.e., . Theoretical implications of our results are discussed. The reason
why the electron-phonon relaxation rate is negligibly weak in this
low-carrier-concentration material is presented.Comment: 10 pages, 7 figure
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