1,874 research outputs found
Spacetime structure of 5D hypercylindrical vacuum solutions with tension
We investigate geometrical properties of 5D cylindrical vacuum solutions with
a transverse spherical symmetry. The metric is uniform along the fifth
direction and characterized by tension and mass densities. The solutions are
classified by the tension-to-mass ratio. One particular example is the
well-known Schwarzschild black string which has a curvature singularity
enclosed by a horizon. We focus mainly on geometry of other solutions which
possess a naked singularity. The light signal emitted by an object approaching
the singularity reaches a distant observer with finite time, but is infinitely
red-shifted.Comment: revtex4, 5 pages, 2 figures. To appear in the proceedings of the 10th
Asia Pacific Physics Conference (APPC10), Pohang, Korea, 21-24 Aug. 2007.
Submitted to J. Korean Phys. Soc. Penrose diagram has been adde
Apoptotic properties of polysaccharide isolated from fruiting bodies of medicinal mushroom Fomes fomentarius in human lung carcinoma cell line
AbstractMushrooms are known to complement chemotherapy and radiation therapy by countering the side effects of cancer. Recently, there has been great interest in isolation of novel bioactive compounds from mushrooms due to their numerous health beneficial effects. Chemically water-extractable polysaccharide (MFKF-AP1β), with a molecular weight of 12kDa, was isolated from fruiting bodies of mushroom Fomes fomentarius. In this research, we investigated the anti-tumor effects of MFKF-AP1β on human lung carcinoma A549 cells. Results showed that MFKF-AP1β markedly inhibited A549 cell growth in a dose-dependent manner based on the amount of lactate dehydrogenase (LDH) released and morphological alterations. In addition, MFKF-AP1β induced cellular apoptosis by causing single-stranded DNA breakage, as evidenced by apoptosis assay. Furthermore, MFKF-AP1β (25–100μg/ml) significantly induced single-stranded DNA breakage in A549 cells, as shown by comet assay.Taken together, our results demonstrate that MFKF-AP1β has strong anti-tumor effects mediated through induction of apoptosis. Therefore, MFKF-AP1β could be useful in lung chemotherapy
Simple and Reliable Position Sense Assessment Under Different External Torques: Toward Developing a Post-Stroke Proprioception Evaluation Device
Evaluation of position sense post-stroke is essential for rehabilitation. Position sense may be an output of a process needing position information, external torque, and the sense of effort. Even for healthy individuals, it is unclear whether external torque affects position sense. Thus, evaluation of position sense under different external torques in clinical settings is strongly needed. However, simple devices for measuring position sense under different external torques in clinical settings are lacking. Technologically advanced devices that may evaluate the elbow position sense under different torques were reported to be infeasible clinically because of device complexity and the need for technical experts when analyzing data. To address the unmet need, in this study, a simple and light elbow position sense measurement device was developed that allows clinicians to measure elbow position sense under different external torques in the form of position matching error objectively without any technical difficulties. The feasibility of the device, including intra-session intra-rater reliability and test-retest reliability over two consecutive days, was verified to be clinically applicable using tests with 25 healthy subjects. Thanks to its ease of use, high reliability, and ease of data analysis, it is expected that the device can help to evaluate the position sense post-stroke comprehensively
Computer use at work is associated with self-reported depressive and anxiety disorder
Adjusted OR* of DAD considering the combined effect of computer use and occupational group, education, and job status. (DOC 61 kb
Supplementation of H1N1pdm09 Split Vaccine with Heterologous Tandem Repeat M2e5x Virus-like Particles Confers Improved Cross-Protection in Ferrets
Current influenza vaccines induce strain-specific immunity to the highly variable hemagglutinin (HA) protein. It is therefore a high priority to develop vaccines that induce broadly cross-protective immunity to different strains of influenza. Since influenza A M2 proteins are highly conserved among different strains, five tandem repeats of the extracellular peptide of M2 in a membrane-anchored form on virus- like particles (VLPs) have been suggested to be a promising candidate for universal influenza vaccine. In this study, ferrets were intramuscularly immunized with 2009 H1N1 split HA vaccine (“Split”) alone, influenza split vaccine supplemented with M2e5x VLP (“Split+M2e5x”), M2e5x VLP alone (“M2e5x”), or mock immunized. Vaccine efficacy was measured serologically and by protection against a sero- logically distinct viral challenge. Ferrets immunized with Split+M2e5x induced HA strain specific and conserved M2e immunity. Supplementation of M2e5x VLP to split vaccination significantly increased the immunogenicity of split vaccine compared to split alone. The Split+M2e5x ferret group showed evidence of cross-reactive protection, including faster recovery from weight loss, and reduced inflammation, as inferred from changes in peripheral leukocyte subsets, compared to mock-immunized animals. In addi- tion, ferrets immunized with Split+M2e5x shed lower viral nasal-wash titers than the other groups. Ferrets immunized with M2e5x alone also show some protective effects, while those immunized with split vaccine alone induced no protective effects compared to mock-immunized ferrets. These stud- ies suggest that supplementation of split vaccine with M2e5x-VLP may provide broader and improved cross-protection than split vaccine alone
Percutaneous Endoscopic Removal of Extruded Centering Pin in Lumbar Artificial Disc Causing Postoperative Radiculopathy: A Case Report
We present a case of postoperative radiculopathy caused by extrusion of centering pin marker in lumbar artificial disc treated by percutaneous endoscopic procedure. A 39-year-old man was presented with intermittent electric shock like left leg pain along S1 dermatome. He received lumbar total disc replacement (TDR) on L5-S1 for his degenerative disc disease (DDD) six years before the revisit to the clinic. X-ray and CT revealed extruded pin from the core of the implant compressing the thecal sac and left S1 root. The position and mobility of the implant were seen intact in follow-up X-rays. The marker pin was removed by percutaneous endoscopic interlaminar technique. The patient’s preoperative leg pain was completely resolved after the procedure
Mechanisms of Cross-protection by Influenza Virus M2-based Vaccines
Current influenza virus vaccines are based on strain-specific surface glycoprotein hemagglutinin (HA) antigens and effective only when the predicted vaccine strains and circulating viruses are well-matched. The current strategy of influenza vaccination does not prevent the pandemic outbreaks and protection efficacy is reduced or ineffective if mutant strains emerge. It is of high priority to develop effective vaccines and vaccination strategies conferring a broad range of cross protection. The extracellular domain of M2 (M2e) is highly conserved among human influenza A viruses and has been utilized to develop new vaccines inducing cross protection against different subtypes of influenza A virus. However, immune mechanisms of cross protection by M2e-based vaccines still remain to be fully elucidated. Here, we review immune correlates and mechanisms conferring cross protection by M2e-based vaccines. Molecular and cellular immune components that are known to be involved in M2 immune-mediated protection include antibodies, B cells, T cells, alveolar macrophages, Fc receptors, complements, and natural killer cells. Better understanding of protective mechanisms by immune responses induced by M2e vaccination will help facilitate development of broadly cross protective vaccines against influenza A virus
Do Quiescent and Active Galaxies Have Different M_(BH)-σ* Relations?
To investigate the validity of the assumption that quiescent galaxies and active galaxies follow the same black hole mass (M_BH)-stellar velocity dispersion (σ*) relation, as required for the calibration of M_BH estimators for broad line active galactic nuclei (AGNs), we determine and compare the M_BH-σ* relations, respectively, for quiescent and active galaxies. For the quiescent galaxy sample, composed of 72 dynamical M_BH measurements, we update σ* for 28 galaxies using homogeneous H-band measurements that are corrected for galaxy rotation. For active galaxies, we collect 25 reverberation-mapped AGNs and improve σ* measurement for two objects. Combining the two samples, we determine the virial factor f, first by scaling the active galaxy sample to the M_BH-σ* relation of quiescent galaxies, and second by simultaneously fitting the quiescent and active galaxy samples, as f=5.1^(+1.5)_(-1.1) and f=5.9^(+2.1)_(-1.5), respectively. The M_BH-σ* relation of active galaxies appears to be shallower than that of quiescent galaxies. However, the discrepancy is caused by a difference in the accessible M_BH distribution at given σ*, primarily due to the difficulty of measuring reliable stellar velocity dispersion for the host galaxies of luminous AGNs. Accounting for the selection effects, we find that active and quiescent galaxies are consistent with following intrinsically the same M_BH-σ* relation
Calibrating Stellar Velocity Dispersions Based on Spatially Resolved H-band Spectra for Improving the M_(BH)-σ_* Relation
To calibrate stellar velocity dispersion measurements from optical and near-IR stellar lines, and to improve the black hole mass (M_(BH))-stellar velocity dispersion (σ_*) relation, we measure σ_* based on high-quality H-band spectra for a sample of 31 nearby galaxies, for which dynamical M_(BH) is available in the literature. By comparing velocity dispersions measured from stellar lines in the H-band with those measured from optical stellar lines, we find no significant difference, suggesting that optical and near-IR stellar lines represent the same kinematics and that dust effect is negligible for early-type galaxies. Based on the spatially resolved rotation and velocity dispersion measurements along the major axis of each galaxy, we find that a rotating stellar disk is present for 80% of galaxies in the sample. For galaxies with a rotation component, σ_* measured from a single aperture spectrum can vary by up to ~20%, depending on the size of the adopted extraction aperture. To correct for the rotational broadening, we derive luminosity-weighted σ_* within the effective radius of each galaxy, providing uniformly measured velocity dispersions to improve the M_(BH)-σ_* relation
Development of a Solid-Phase Colorimetric Assay for the Screening of Transglutaminase Activities
A solid-phase colorimetric assay method for transglutaminase activities
has been developed. The principle of the assay is to monitor cross-linking activities between
casein bound to microtiter plates and free biotinylated casein by the sample.
Quantitation of immobilized biotin-labeled casein formation through the enzymatic reaction
was conducted by avidin or streptavidin conjugated enzymes. For this purpose,
the efficiency of four different reporter enzymes (streptavidin or avidin conjugated alkaline
phosphatase, streptavidin or avidin conjugated horseradish peroxidase) was
compared, especially focusing on the sensitivity and specificity of the respective
methods. The newly developed assay method was applied to the procedure of
transglutaminase C purification from human erythrocytes and proven to have good correlation
with conventional C14 putrescine method (r = 0.85, p(0.05). Moreover, since
this new method can detect enzymatic activity without use of radioisotope and can process
a number of samples simultaneously, it is possible to screen a mass population for
transglutaminase deficiency, such as factor XIII, in routine clinical laboratories
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