1,231 research outputs found
Towards Efficient Path Query on Social Network with Hybrid RDF Management
The scalability and exibility of Resource Description Framework(RDF) model
make it ideally suited for representing online social networks(OSN). One basic
operation in OSN is to find chains of relations,such as k-Hop friends. Property
path query in SPARQL can express this type of operation, but its implementation
suffers from performance problem considering the ever growing data size and
complexity of OSN.In this paper, we present a main memory/disk based hybrid RDF
data management framework for efficient property path query. In this hybrid
framework, we realize an efficient in-memory algebra operator for property path
query using graph traversal, and estimate the cost of this operator to
cooperate with existing cost-based optimization. Experiments on benchmark and
real dataset demonstrated that our approach can achieve a good tradeoff between
data load expense and online query performance
Positron Source Simulations for ILC 1 TeV Upgrade
The generation and capture of polarized positrons at a source with a
superconducting helical undulator having 4.3 cm period and 500 GeV electron
drive beam have been simulated. The positron polarization has been calculated
for the different undulator K values (up to K = 2.5). Without applying a photon
collimator, the maximal polarization of positrons is about 25% for 231 meters
active magnet length of undulator with K = 0.7. Using an undulator with K = 2.5
and a collimator with an aperture radius of 0.9 mm results in increase of
positron polarization to 54%. The energy deposition, temperature rise and
stress induced by high intense photon beam in the rotated titanium-alloy target
have been estimated. The maximal thermal stress in the target is about 224 MPa
for the source with photon collimation to achieve a positron polarization of
54%.Comment: 8 pages, 9 figures, 1 tabl
Heteroepitaxial growth of ZnO branches selectively on TiO2 nanorod tips with improved light harvesting performance
A seeded heteroepitaxial growth of ZnO nanorods selectively on TiO2 nanorod tips was achieved by restricting crystal growth on highly hydrophobic TiO2 nanorod film surfaces. Intriguing light harvesting performance and efficient charge transport efficiency has been found, which suggest potential applications in photovoltaics and optoelectronics
Integrable deformations of the Bogoyavlenskij-Itoh Lotka-Volterra systems
We construct a family of integrable deformations of the Bogoyavlenskij-Itoh
systems and construct a Lax operator with spectral parameter for it. Our
approach is based on the construction of a family of compatible Poisson
structures for the undeformed system, whose Casimirs are shown to yield a
generating function for the integrals in involution of the deformed systems. We
show how these deformations are related to the Veselov-Shabat systems.Comment: 23 pages, 14 reference
Dipeptidyl Peptidase 10 (DPP10789): A Voltage Gated Potassium Channel Associated Protein Is Abnormally Expressed in Alzheimer’s and Other Neurodegenerative Diseases
Copyright © 2014 Tong Chen et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.The neuropathological features associated with Alzheimer’s disease (AD) include the presence of extracellular amyloid- peptidecontaining
plaques and intracellular tau positive neurofibrillary tangles and the loss of synapses and neurons in defined regions of
the brain. Dipeptidyl peptidase 10 (DPP10) is a protein that facilitates Kv4 channel surface expression and neuronal excitability. This
study aims to explore DPP10789 protein distribution in human brains and its contribution to the neurofibrillary pathology of AD
and other tauopathies. Immunohistochemical analysis revealed predominant neuronal staining of DPP10789 in control brains, and
the CA1 region of the hippocampus contained strong reactivity in the distal dendrites of the pyramidal cells. In AD brains, robust
DPP10789 reactivity was detected in neurofibrillary tangles and plaque-associated dystrophic neurites, most of which colocalized
with the doubly phosphorylated Ser-202/Thr-205 tau epitope. DPP10789 positive neurofibrillary tangles and plaque-associated
dystrophic neurites also appeared in other neurodegenerative diseases such as frontotemporal lobar degeneration, diffuse Lewy
body disease, and progressive supranuclear palsy. Occasional DPP10789 positive neurofibrillary tangles and neurites were seen in
some aged control brains.Western blot analysis showed both full length and truncatedDPP10789 fragments with the later increasing
significantly in AD brains compared to control brains. Our results suggest that DPP10789 is involved in the pathology of AD and
other neurodegenerative diseases
Identification of a novel regulatory mechanism involved in inhibition of transcription of suvivin mRNA in breast cancer cells via p21cip–mediated regulation
Purpose: To evaluate the effect of p21Cip1 on survivin transcription levels in breast carcinoma, and to investigate the potential mechanisms.Methods: Epirubicin, a p21Cip1 activator, was used to treat MCF7 cells. Under the action of normal biological functions of p53, pEGFP-C2-p21 was transfected into MCF7 cells by lipofectamine and positive clones were screened out with G418. The expression levels of p21cip1, p53 and survivin mRNA were quantitated by real-time fluorescent polymerase chain reaction (RQ-PCR). MTT assay was utilized to measure cellular viability and proliferation after transfection. Flow cytometry was employed to determine the cell cycle. Hoechst 33342 staining was carried out to assess cell apoptosis. Lastly, several transcription factor sites located at the promoter region of survivin gene, such as, sp1 site, E2F site and p300/CBP, were measured by p21 overexpression using RT-PCR.Results: Following epirubicin treatment, within 24 h, the expression levels of endogenous p21cip1 and p53 were up-regulated, whereas that of survivin was down-regulated. After transfection treatment, p21 inhibited the proliferation of MCF7 cells on days 3 and 4, and MCF7 cells overexpressed p21 mRNA, whereas the level of survivin mRNA in MCF7-p21 groups was markedly down-regulated relative to control group, but overexpression of p21 was not sufficient to cause changes in p53 gene expression. The overexpressed p21 resulted in G1/G0 phase arrest based on cell cycle analysis, but apoptosis was not induced. In addition, co-transcription factors E2F-1, sp1 and p300/CBP mRNA levels decreased significantly compared with normal p21 expression groups.Conclusion: P21cip1 may down-regulate the expression of survivin gene partially by inhibiting the expression level of HAT.Keywords: Cyclin-dependent kinase inhibitor 1, Phosphoprotein p53, Survivin, Breast carcinoma, G1/G0 phase arrest, Epirubicin, Lipofectamin
- …