251 research outputs found
Top quark spin and interaction in charged Higgs and top quark associated production at LHC
We study the charged Higgs production at LHC via its associated production
with top quark. The kinematic cuts are optimized to suppress the background
processes so that the reconstruction of the charged Higgs and top quark is
possible. The angular distributions with respect to top quark spin are explored
to study the interaction at LHC.Comment: 10 pages,5 figures, to appear in PR
Upregulation of microRNA-25 associates with prognosis in hepatocellular carcinoma
BACKGROUND: Accumulating evidence has shown that up-regulation of microRNA-25(miR-25) is associated with the prognosis of several types of human malignant solid tumors. However, whether miR-25 expression has influence on the prognosis of hepatocellular carcinoma (HCC) is still unknown. METHODS: The differentially expressed amount of the miR-25 was validated in triplicate by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Survival rate was analyzed by log-rank test, and survival curves were plotted according to Kaplan–Meier. Multivariate analysis of the prognostic factors was performed with Cox regression model. RESULTS: The expression of miR-25 was significantly upregulated in HCC tissues when compared with adjacent normal tissues (p<0.0001). Patients who had high miR-25 expression had a shorter overall survival than patients who had low miR-25 expression (median overall survival, 31.0 months versus 42.9 months, p=0.0192). The multivariate Cox regression analysis indicated that miR-25 expression (HR=2.179; p=0.001), TNM stage (HR=1.782; p=0.014), and vein invasion (HR=1.624; p=0.020) were independent prognostic factors for overall survival. CONCLUSION: Our data suggests that the overexpression of miR-25 in HCC tissues is of predictive value on poor prognosis. VIRTUAL SLIDE: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/198961842111430
Application of Local Wave Decomposition in Seismic Signal Processing
Local wave decomposition (LWD) method plays an important role in seismic signal processing for its superiority in significantly revealing the frequency content of a seismic signal changes with time variation. The LWD method is an effective way to decompose a seismic signal into several individual components. Each component represents a harmonic signal localized in time, with slowly varying amplitudes and frequencies, potentially highlighting different geologic and stratigraphic information. Empirical mode decomposition (EMD), the synchrosqueezing transform (SST), and variational mode decomposition (VMD) are three typical LWD methods. We mainly study the application of the LWD method especially EMD, SST, and VMD in seismic signal processing including seismic signal de‐noising, edge detection of seismic images, and recovery of the target reflection near coal seams
A Search for Double-peaked narrow emission line Galaxies and AGNs in the LAMOST DR1
LAMOST has released more than two million spectra, which provide the
opportunity to search for double-peaked narrow emission line (NEL) galaxies and
AGNs. The double-peaked narrow-line profiles can be well modeled by two
velocity components, respectively blueshifted and redshifted with respect to
the systemic recession velocity. This paper presents 20 double-peaked NEL
galaxies and AGNs found from LAMOST DR1 using a search method based on
multi-gaussian fit of the narrow emission lines. Among them, 10 have already
been published by other authors, either listed as genuine double-peaked NEL
objects or as asymmetric NEL objects, the remaining 10 being first discoveries.
We discuss some possible origins for double-peaked narrow-line features, as
interaction between jet and narrow line regions, interaction with companion
galaxies and black hole binaries. Spatially resolved optical imaging and/or
follow-up observations in other spectral bands are needed to further discuss
the physical mechanisms at work.Comment: 17 pages, 5figures, 4 tables, accepted by RA
Recommended from our members
A Comparison of Computational Methods for Identifying Virulence Factors
Bacterial pathogens continue to threaten public health worldwide today. Identification of bacterial virulence factors can help to find novel drug/vaccine targets against pathogenicity. It can also help to reveal the mechanisms of the related diseases at the molecular level. With the explosive growth in protein sequences generated in the postgenomic age, it is highly desired to develop computational methods for rapidly and effectively identifying virulence factors according to their sequence information alone. In this study, based on the protein-protein interaction networks from the STRING database, a novel network-based method was proposed for identifying the virulence factors in the proteomes of UPEC 536, UPEC CFT073, P. aeruginosa PAO1, L. pneumophila Philadelphia 1, C. jejuni NCTC 11168 and M. tuberculosis H37Rv. Evaluated on the same benchmark datasets derived from the aforementioned species, the identification accuracies achieved by the network-based method were around 0.9, significantly higher than those by the sequence-based methods such as BLAST, feature selection and VirulentPred. Further analysis showed that the functional associations such as the gene neighborhood and co-occurrence were the primary associations between these virulence factors in the STRING database. The high success rates indicate that the network-based method is quite promising. The novel approach holds high potential for identifying virulence factors in many other various organisms as well because it can be easily extended to identify the virulence factors in many other bacterial species, as long as the relevant significant statistical data are available for them
Twin sisters with Hashimoto’s thyroiditis and Henoch-Schönlein purpura
Not required for Clinical Vignette
Assessing the Effect of Simultaneous Combining of Transcranial Direct Current Stimulation and Transcutaneous Auricular Vagus Nerve Stimulation on the Improvement of Working Memory Performance in Healthy Individuals
A previous study found that combining transcranial direct current stimulation (tDCS) and transcutaneous auricular vagus nerve stimulation (taVNS) could evoke significantly larger activation on a range of cortical and subcortical brain regions than the numerical summation of tDCS and taVNS effects. In this study, two within-subject experiments were employed to investigate its effects on working memory (WM). In experiment 1, the WM modulatory effects of tDCS over the left dorsolateral prefrontal cortex (DLPFC), taVNS, and simultaneous joint simulation of tDCS over the left DLPFC and taVNS (SJS-L) were compared among 60 healthy subjects. They received these three interventions between the baseline test and post-test in a random manner three times. In spatial 3-back task, there was a significant interaction between time and stimulations in the accuracy rate of matching trials (mACC, p=0.018). MACCs were significantly improved by SJS (p = 0.001) and taVNS (p = 0.045), but not by tDCS (p = 0.495). Moreover, 41 subjects in the SJS group showed improvement, which was significantly larger than that in the taVNS group (29 subjects) and tDCS group (26 subjects). To further investigate the generalization effects of SJS, 72 students were recruited in experiment 2. They received tDCS over the right DLPFC, taVNS, simultaneous joint simulation of tDCS over the right DLPFC and taVNS (SJS-R), and sham stimulation in a random manner four times. No significant results were found, but there was a tendency similar to experiment 1 in the spatial 3-back task. In conclusion, combining tDCS and taVNS might be a potential non-invasive neuromodulation technique which is worthy of study in future
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
Mitochondrial Protection and Anti-aging Activity of Astragalus Polysaccharides and Their Potential Mechanism
The current study was performed to investigate mitochondrial protection and anti-aging activity of Astragalus polysaccharides (APS) and the potential underlying mechanism. Lipid peroxidation of liver and brain mitochondria was induced by Fe2+–Vit C in vitro. Thiobarbituric acid (TBA) colorimetry was used to measure the content of thiobarbituric acid reactive substances (TBARS). Mouse liver mitochondrial permeability transition (PT) was induced by calcium overload in vitro and spectrophotometry was used to measure it. The scavenging activities of APS on superoxide anion (O2•−) and hydroxyl radical (•OH), which were produced by reduced nicotinamide adenine dinucleotide (NADH)—N-Methylphenazonium methyl sulfate (PMS) and hydrogen peroxide (H2O2)–Fe2+ system respectively, were measured by 4-nitrobluetetrazolium chloride (NBT) reduction and Fenton reaction colorimetry respectively. The Na2S2O3 titration method was used to measure the scavenging activities of APS on H2O2. APS could inhibit TBARS production, protect mitochondria from PT, and scavenge O2•−, •OH and H2O2 significantly in a concentration-dependent manner respectively. The back of the neck of mice was injected subcutaneously with D-galactose to induce aging at a dose of 100 mg/kg/d for seven weeks. Moreover, the activities of catalase (CAT), surperoxide dismutase (SOD) and glutathione peroxidase (GPx) and anti-hydroxyl radical which were assayed by using commercial monitoring kits were increased significantly in vivo by APS. According to this research, APS protects mitochondria by scavenging reactive oxygen species (ROS), inhibiting mitochondrial PT and increasing the activities of antioxidases. Therefore, APS has the effect of promoting health
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