154 research outputs found
Visualizing the elongated vortices in -Ga nanostrips
We study the magnetic response of superconducting -Ga via low
temperature scanning tunneling microscopy and spectroscopy. The magnetic vortex
cores rely substantially on the Ga geometry, and exhibit an unexpectedly-large
axial elongation with aspect ratio up to 40 in rectangular Ga nano-strips
(width 100 nm). This is in stark contrast with the isotropic circular
vortex core in a larger round-shaped Ga island. We suggest that the unusual
elongated vortices in Ga nanostrips originate from geometric confinement effect
probably via the strong repulsive interaction between the vortices and Meissner
screening currents at the sample edge. Our finding provides novel conceptual
insights into the geometrical confinement effect on magnetic vortices and forms
the basis for the technological applications of superconductors.Comment: published in Phys. Rev. B as a Rapid Communicatio
Experimental study of THGEM detector with mini-rim
The gas gain and energy resolution of single and double THGEM detectors
(5{\times}5cm2 effective area) with mini-rims (rim is less than 10{\mu}m) were
studied. The maximum gain can reach 5{\times}103 and 2{\times}105 for single
and double THGEM respectively, while the energy resolution of 5.9 keV X-ray
varied from 18% to 28% for both single and double THGEM detectors of different
hole sizes and thicknesses.All the experiments were investigated in mixture of
noble gases(argon,neon) and small content of other gases(iso-butane,methane) at
atmospheric pressure.Comment: 4pages,6figures, it has been submitted to Chinese Physics
Screening and Identification of B-Cell Epitopes in the P61 Protein of Nocardia brasiliensis
The P61 protein is an immunodominant antigen of Nocardia brasiliensis that is observed in the sera from patients infected with the bacterium. However, the B-cell epitopes of N. brasiliensis are still unresolved. To identify the antigenic determinants of P61, we screened seven monoclonal antibodies (mAbs) against P61 protein that was expressed in the Escherichia coli system. A series of truncated peptides of P61 were then generated and the mAbs were used to screen these peptides by Western blot analyses. Three B-cell epitopes were recognized by the P61 specific mAbs: 461-FEYWTKVDPEIGKRIEEG-478, 427-LVREVFNDAQRDRLVSNVVGGVQEPV. LSRVFEYWTKVDPEIGKRIEEGVRAG-482, and 447-HVLGGVQEPVLSRVFEY WTKVDPEI GKRIEEGVRAGLD-484. The latter two epitopes were further identified by N. brasiliensis-infected mouse serum. These results facilitate future investigations of serodiagnostic methods to identify Nocardia infections
Marsdenia tenacissima enhances immune response of tumor infiltrating T lymphocytes to colorectal cancer
IntroductionTumor-infiltrating T lymphocytes in the tumor microenvironment are critical factors influencing the prognosis and chemotherapy outcomes. As a Chinese herbal medicine, Marsdenia tenacissima extract (MTE) has been widely used to treat cancer in China. Its immunoregulatory effects on tumor-associated macrophages is well known, but whether it regulates tumor-infiltrating T-cell functions remains unclear.MethodWe collected 17 tumor samples from MTE-administered colorectal cancer patients, 13 of which showed upregulation of CD3+/CD8+ tumor-infiltrating T cells. Further in vitro and in vivo experiments were performed to investigate the regulatory effects of MTE on tumor-infiltrating T cells and immune escape of tumors.ResultsUnder single and co-culture conditions, MTE inhibited TGF-β1 and PD-L1 expression in the colorectal cancer (CRC) cell lines HCT116 and LoVo. In Jurkat cells, MTE inhibited FOXP3 and IL-10 expression, increased IL-2 expression, but had no effect on PD-1 expression. These findings were confirmed in vitro using subcutaneous and colitis-associated CRC mouse models. MTE also increased the density of CD3+/CD8+ tumor-infiltrating T cells and exhibited considerable tumor-suppressive effects in these two tumor mouse models.ConclusionsOur findings suggested that MTE inhibits the immune escape of cancer cells, a precipitating factor increasing the immune response of T lymphocytes
The LAMOST Survey of Background Quasars in the Vicinity of the Andromeda and Triangulum Galaxies -- II. Results from the Commissioning Observations and the Pilot Surveys
We present new quasars discovered in the vicinity of the Andromeda and
Triangulum galaxies with the LAMOST during the 2010 and 2011 observational
seasons. Quasar candidates are selected based on the available SDSS, KPNO 4 m
telescope, XSTPS optical, and WISE near infrared photometric data. We present
509 new quasars discovered in a stripe of ~135 sq. deg from M31 to M33 along
the Giant Stellar Stream in the 2011 pilot survey datasets, and also 17 new
quasars discovered in an area of ~100 sq. deg that covers the central region
and the southeastern halo of M31 in the 2010 commissioning datasets. These 526
new quasars have i magnitudes ranging from 15.5 to 20.0, redshifts from 0.1 to
3.2. They represent a significant increase of the number of identified quasars
in the vicinity of M31 and M33. There are now 26, 62 and 139 known quasars in
this region of the sky with i magnitudes brighter than 17.0, 17.5 and 18.0
respectively, of which 5, 20 and 75 are newly-discovered. These bright quasars
provide an invaluable collection with which to probe the kinematics and
chemistry of the ISM/IGM in the Local Group of galaxies. A total of 93 quasars
are now known with locations within 2.5 deg of M31, of which 73 are newly
discovered. Tens of quasars are now known to be located behind the Giant
Stellar Stream, and hundreds behind the extended halo and its associated
substructures of M31. The much enlarged sample of known quasars in the vicinity
of M31 and M33 can potentially be utilized to construct a perfect astrometric
reference frame to measure the minute PMs of M31 and M33, along with the PMs of
substructures associated with the Local Group of galaxies. Those PMs are some
of the most fundamental properties of the Local Group.Comment: 26 pages, 6 figures, AJ accepte
Charge-changing cross section measurements of 300 MeV/nucleon Si on carbon and data analysis
Charge-changing cross section () measurements via the
transmission method have made important progress recently aiming to determine
the charge radii of exotic nuclei. In this work, we report a new
measurement of 304(9) MeV/nucleon Si on carbon at
the second Radioactive Ion Beam Line in Lanzhou (RIBLL2) and describe the data
analysis procedure in detail. This procedure is essential to evaluate the
systematic uncertainty in the transmission method. The determined
of 1125(11) mb is found to be consistent with the
existing data at similar energies. The present work will serve as a reference
in the determinations at RIBLL2.Comment: 9 pages, 13 figures, to be published in Chinese Physics
Genomic and oncogenic preference of HBV integration in hepatocellular carcinoma
Hepatitis B virus (HBV) can integrate into the human genome, contributing to genomic instability and hepatocarcinogenesis. Here by conducting high-throughput viral integration detection and RNA sequencing, we identify 4,225 HBV integration events in tumour and adjacent non-tumour samples from 426 patients with HCC. We show that HBV is prone to integrate into rare fragile sites and functional genomic regions including CpG islands. We observe a distinct pattern in the preferential sites of HBV integration between tumour and non-tumour tissues. HBV insertional sites are significantly enriched in the proximity of telomeres in tumours. Recurrent HBV target genes are identified with few that overlap. The overall HBV integration frequency is much higher in tumour genomes of males than in females, with a significant enrichment of integration into chromosome 17. Furthermore, a cirrhosis-dependent HBV integration pattern is observed, affecting distinct targeted genes. Our data suggest that HBV integration has a high potential to drive oncogenic transformation
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