4,621 research outputs found
Video retrieval based on deep convolutional neural network
Recently, with the enormous growth of online videos, fast video retrieval
research has received increasing attention. As an extension of image hashing
techniques, traditional video hashing methods mainly depend on hand-crafted
features and transform the real-valued features into binary hash codes. As
videos provide far more diverse and complex visual information than images,
extracting features from videos is much more challenging than that from images.
Therefore, high-level semantic features to represent videos are needed rather
than low-level hand-crafted methods. In this paper, a deep convolutional neural
network is proposed to extract high-level semantic features and a binary hash
function is then integrated into this framework to achieve an end-to-end
optimization. Particularly, our approach also combines triplet loss function
which preserves the relative similarity and difference of videos and
classification loss function as the optimization objective. Experiments have
been performed on two public datasets and the results demonstrate the
superiority of our proposed method compared with other state-of-the-art video
retrieval methods
Behavior of hybrid FRP-concrete-steel tubular columns : experimental and theoretical studies
2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Mathieu twining characters for K3
The analogue of the McKay-Thompson series for the proposed Mathieu group
action on the elliptic genus of K3 is analysed. The corresponding NS-sector
twining characters have good modular properties and satisfy remarkable
replication identities. These observations provide strong support for the
conjecture that the elliptic genus of K3 carries indeed an action of the
Mathieu group M24.Comment: 19 page
Predictor Model of Root Caries in Older Adults: Reporting of Evidence to the Translational Evidence Mechanism
Compared to younger adults, older adults are at greater risk for root caries. A model of root caries may assist dentists in predicting disease outcomes. OBJECTIVES: Using the Iowa 65+ Oral Health Survey, analysis was done to model the patterns of the root caries development in older adults
Experimental modulation of capsule size in Cryptococcus neoformans
Experimental modulation of capsule size is an important technique for the study of the virulence of the encapsulated pathogen Cryptococcus neoformans. In this paper, we summarize the techniques available for experimental modulation of capsule size in this yeast and describe improved methods to induce capsule size changes. The response of the yeast to the various stimuli is highly dependent on the cryptococcal strain. A high CO(2) atmosphere and a low iron concentration have been used classically to increase capsule size. Unfortunately, these stimuli are not reliable for inducing capsular enlargement in all strains. Recently we have identified new and simpler conditions for inducing capsule enlargement that consistently elicited this effect. Specifically, we noted that mammalian serum or diluted Sabouraud broth in MOPS buffer pH 7.3 efficiently induced capsule growth. Media that slowed the growth rate of the yeast correlated with an increase in capsule size. Finally, we summarize the most commonly used media that induce capsule growth in C. neoformans
Co3O4 Nanocrystals on Graphene as a Synergistic Catalyst for Oxygen Reduction Reaction
Catalysts for oxygen reduction and evolution reactions are at the heart of
key renewable energy technologies including fuel cells and water splitting.
Despite tremendous efforts, developing oxygen electrode catalysts with high
activity at low costs remains a grand challenge. Here, we report a hybrid
material of Co3O4 nanocrystals grown on reduced graphene oxide (GO) as a
high-performance bi-functional catalyst for oxygen reduction reaction (ORR) and
oxygen evolution reaction (OER). While Co3O4 or graphene oxide alone has little
catalytic activity, their hybrid exhibits an unexpected, surprisingly high ORR
activity that is further enhanced by nitrogen-doping of graphene. The
Co3O4/N-doped graphene hybrid exhibits similar catalytic activity but superior
stability to Pt in alkaline solutions. The same hybrid is also highly active
for OER, making it a high performance non-precious metal based bi-catalyst for
both ORR and OER. The unusual catalytic activity arises from synergetic
chemical coupling effects between Co3O4 and graphene.Comment: published in Nature Material
Basal Forebrain Mediated Increase in Brain CRF is Associated with Increased Cholinergic Tone and Depression
Major depression is a devastating disease that generates significant suffering and cost.
After controlling for the main effects of diagnosis and Cerebrospinal Fluid Corticotropin-Releasing Factor (CSF CRF), the interaction between CSF CRF and major depression disorder diagnosis was a significant predictor of basal forebrain cholinergic nuclei volume, but not of hippocampal volume.
By investigating both markers concurrently in participants with and without depression, we describe the extent to which the interaction between CSF CRF levels and depression diagnosis is associated with the volume of the forebrain cholinergic nuclei and of the hippocampus.
These results contribute to our understanding of the role of brain’s stress axis in depression
Characterization of High-Fat, Diet-Induced, Non-alcoholic Steatohepatitis with Fibrosis in Rats
An ideal animal model is necessary for a clear understanding of the etiology, pathogenesis, and mechanisms of human non-alcoholic steatohepatitis (NASH) and for facilitating the design of effective therapy for this condition. We aimed to establish a rat model of NASH with fibrosis by using a high-fat diet (HFD). Male Sprague–Dawley (SD) rats were fed a HFD consisting of 88 g normal diet, 10 g lard oil, and 2 g cholesterol. Control rats were fed normal diet. Rats were killed at 4, 8, 12, 16, 24, 36, and 48 weeks after HFD exposure. Body weight, liver weight, and epididymal fat weight were measured. Serum levels of fasting glucose, triglyceride, cholesterol, alanine aminotransferase (ALT), free fatty acids (FFA), insulin, and tumor necrosis factor-alpha (TNF-α) were determined. Hepatic histology was examined by H&E stain. Hepatic fibrosis was assessed by VG stain and immunohistochemical staining for transforming growth factor beta 1 (TGF-β1), and alpha-smooth-muscle actin (α-SMA). The liver weight and liver index increased from week 4, when hepatic steatosis was also observed. By week 8, the body weight and epididymal fat weight started increasing, which was associated with increased serum levels of FFA, cholesterol, and TNF-α, as well as development of simple fatty liver. The serum ALT level increased from week 12. Steatohepatitis occurred from weeks 12 through 48. Apparent hepatic perisinosodial fibrosis did not occur until week 24, and progressed from week 36 to 48 with insulin resistance. Therefore, this novel model may be potentially useful in NASH study
Lifshitz-like space-time from intersecting branes in string/M theory
We construct 1/4 BPS, threshold F-D bound states (with )
of type II string theories by applying S- and T-dualities to the D1-D5 system
of type IIB string theory. These are different from the known 1/2 BPS,
non-threshold F-D bound states. The near horizon limits of these solutions
yield Lifshitz-like space-times with varying dynamical critical exponent
, for , along with the hyperscaling violation exponent
, showing how Lifshitz-like space-time can be
obtained from string theory. The dilatons are in general non-constant (except
for ). We discuss the holographic RG flows and the phase structures of
these solutions. For , we do not get a Lifshitz-like space-time, but the
near horizon limit in this case leads to an AdS space.Comment: 20 pages, no figure, v2: proper identification of hyperscaling
violation exponent has been made, abstract and the text has been changed
accordingly, note added, v3: minor changes, refs added, version to appear in
JHE
Resonances in and
A partial wave analysis is presented of and
from a sample of 58M events in the BES II detector. The
is observed clearly in both sets of data, and parameters of the
Flatt\' e formula are determined accurately: (stat)
(syst) MeV/c, MeV/c, . The data also exhibit a strong peak
centred at MeV/c. It may be fitted with and a
dominant signal made from interfering with a smaller
component. There is evidence that the signal is
resonant, from interference with . There is also a state in with MeV/c and
MeV/c; spin 0 is preferred over spin 2. This state, , is
distinct from . The data contain a strong peak due to
. A shoulder on its upper side may be fitted by interference
between and .Comment: 17 pages, 6 figures, 1 table. Submitted to Phys. Lett.
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