1,343 research outputs found
Analytical solution of the geodesic equation in Kerr-(anti) de Sitter space-times
The complete analytical solutions of the geodesic equations in Kerr-de Sitter
and Kerr-anti-de Sitter space-times are presented. They are expressed in terms
of Weierstrass elliptic p, zeta, and sigma functions as well as hyperelliptic
Kleinian sigma functions restricted to the one-dimensional theta-divisor. We
analyze the dependency of timelike geodesics on the parameters of the
space-time metric and the test-particle and compare the results with the
situation in Kerr space-time with vanishing cosmological constant. Furthermore,
we systematically can find all last stable spherical and circular orbits and
derive the expressions of the deflection angle of flyby orbits, the orbital
frequencies of bound orbits, the periastron shift, and the Lense-Thirring
effect.Comment: 18 pages, 11 figure
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Neoadjuvant sipuleucel-T induces both Th1 activation and immune regulation in localized prostate cancer.
Sipuleucel-T is the only FDA-approved immunotherapy for metastatic castration-resistant prostate cancer. The mechanism by which this treatment improves survival is not fully understood. We have previously shown that this treatment can induce the recruitment of CD4 and CD8 T cells to the tumor microenvironment. In this study, we examined the functional state of these T cells through gene expression profiling. We found that the magnitude of T cell signatures correlated with the frequency of T cells as measured by immunohistochemistry. Sipuleucel-T treatment was associated with increased expression of Th1-associated genes, but not Th2-, Th17 - or Treg-associated genes. Post-treatment tumor tissues with high CD8+T cell infiltration was associated with high levels of CXCL10 expression. On in situ hybridization, CXCL10+ cells colocalized with CD8+T cells in post-treatment prostatectomy tumor tissue. Neoadjuvant sipuleucel-T was also associated with upregulation of immune inhibitory checkpoints, including CTLA4 and TIGIT, and downregulation of the immune activation marker, dipeptidylpeptidase, DPP4. Treatment-associated declines in serum PSA were correlated with induction of Th1 response. In contrast, rises in serum PSA while on treatment were associated with the induction of multiple immune checkpoints, including CTLA4, CEACAM6 and TIGIT. This could represent adaptive immune resistance mechanisms induced by treatment. Taken together, neoadjuvant sipuleucel-T can induce both a Th1 response and negative immune regulation in the prostate cancer microenvironment
An X-ray Spectroscopic Study of the Hot Interstellar Medium Toward the Galactic Bulge
We present a detailed spectroscopic study of the hot gas toward the Galactic
bulge along the 4U 1820-303 sight line by a combination analysis of emission
and absorption spectra. In addition to the absorption lines of OVII Kalpha,
OVII Kbeta, OVIII Kalpha and NeIX Kalpha by Chandra LTGS as shown by previous
works, Suzaku detected clearly the emission lines of OVII, OVIII, NeIX and NeX
from the vicinity. We used simplified plasma models with constant temperature
and density. Evaluation of the background and foreground emission was performed
carefully, including stellar X-ray contribution based on the recent X-ray
observational results and stellar distribution simulator. If we assume that one
plasma component exists in front of 4U1820-303 and the other one at the back,
the obtained temperatures are T= 1.7 +/- 0.2 MK for the front-side plasma and
T=3.9(+0.4-0.3) MK for the backside. This scheme is consistent with a hot and
thick ISM disk as suggested by the extragalactic source observations and an
X-ray bulge around the Galactic center.Comment: 14 pages, 15 figures, accepted to be published in PASJ (Replace
figure files to fix latex problem
Characterizing Planetary Orbits and the Trajectories of Light
Exact analytic expressions for planetary orbits and light trajectories in the
Schwarzschild geometry are presented. A new parameter space is used to
characterize all possible planetary orbits. Different regions in this parameter
space can be associated with different characteristics of the orbits. The
boundaries for these regions are clearly defined. Observational data can be
directly associated with points in the regions. A possible extension of these
considerations with an additional parameter for the case of Kerr geometry is
briefly discussed.Comment: 49 pages total with 11 tables and 10 figure
Symmetry, bifurcation and stacking of the central configurations of the planar 1+4 body problem
In this work we are interested in the central configurations of the planar
1+4 body problem where the satellites have different infinitesimal masses and
two of them are diametrically opposite in a circle. We can think this problem
as a stacked central configuration too. We show that the configuration are
necessarily symmetric and the other sattelites has the same mass. Moreover we
proved that the number of central configuration in this case is in general one,
two or three and in the special case where the satellites diametrically
opposite have the same mass we proved that the number of central configuration
is one or two saying the exact value of the ratio of the masses that provides
this bifurcation.Comment: 9 pages, 2 figures. arXiv admin note: text overlap with
arXiv:1103.627
燒炭自殺在東亞國家的流行散佈: 趨勢分析
The Abstract Book can be viewed at: http://www.sop.org.tw/book/download/Summary2013.pdfConference Theme: Focusing on Mental Health, Life Care and Social Network in the ElderlyObjective: Suicides by carbon monoxide poisoning resulting from burning barbecue charcoal reached epidemic levels in Hong Kong and Taiwan within 5 years in the early 2000s.
Methods: We used data for suicides by gases other than domestic gas in Hong Kong, Japan, South Korea (1995-2010), Taiwan (1995-2011), and Singapore (1996-2011) to systematically investigate the spread of this method in East Asia. Graphical and joinpoint regression analyses were used to examine suicide trends and Poisson regression analysis to
study sex- and age-specific patterns.
Results: In 1995/1996, charcoal-burning suicides accounted for < 1% of all suicides in all study countries, except around 5% in Japan, but they increased to account for 14%, 28%, 13%, 4.3%, and 3.4% of all suicides in Hong Kong, Taiwan, Japan, South Korea, and Singapore respectively in 2010. Rises were first seen in Hong Kong in 1999, followed by Singapore in 2000, Taiwan in 2001, Japan in 2003, and South Korea in 2008. There was some evidence for an impact on overall suicide trends in Hong Kong, Taiwan, and Japan (females), but not in Japan (males), South Korea, and Singapore. Rates of change did not differ by sex/age group in Taiwan and Hong Kong but were greatest in young people in Japan and middleaged men and young women in South Korea.
Conclusion: Variations in the timing, scale and sex/age pattern of the epidemic appear to be influenced by the media reporting of charcoal-burning suicide, whilst other factors such as the characteristics of the first or first few cases, language and ulture, familiarity and accessibility with the method, and socio-economic conditions may also play a role. Strategies to limit the epidemic spread of new suicide methods include surveillance to enable the early identification of the emergence of such methods, responsible media reporting and restrictions on Internet sites giving technical information about the method
Orbits in the Field of a Gravitating Magnetic Monopole
Orbits of test particles and light rays are an important tool to study the
properties of space-time metrics. Here we systematically study the properties
of the gravitational field of a globally regular magnetic monopole in terms of
the geodesics of test particles and light. The gravitational field depends on
two dimensionless parameters, defined as ratios of the characteristic mass
scales present. For critical values of these parameters the resulting metric
coefficients develop a singular behavior, which has profound influence on the
properties of the resulting space-time and which is clearly reflected in the
orbits of the test particles and light rays.Comment: 24 pages, 15 figures. Accepted for publication in GR
Geodesic equations and algebro-geometric methods
For an investigation of the physical properties of gravitational fields the
observation of massive test particles and light is very useful. The
characteristic features of a given space-time may be decoded by studying the
complete set of all possible geodesic motions. Such a thorough analysis can be
accomplished most effectively by using analytical methods to solve the geodesic
equation. In this contribution, the use of elliptic functions and their
generalizations for solving the geodesic equation in a wide range of well known
space-times, which are part of the general Pleba\'nski-Demia\'nski family of
solutions, will be presented. In addition, the definition and calculation of
observable effects like the perihelion shift will be presented and further
applications of the presented methods will be outlined.Comment: 8 pages, no figures; based on presentation at the conference
"Relativity and Gravitation: 100 Years after Einstein in Prague," Prague,
2012. Relativity and Gravitation, volume 157 of Springer Proceedings in
Physics, p 91. Springer International Publishing, 201
The complete set of solutions of the geodesic equations in the space-time of a Schwarzschild black hole pierced by a cosmic string
We study the geodesic equations in the space-time of a Schwarzschild black
hole pierced by an infinitely thin cosmic string and give the complete set of
analytical solutions of these equations for massive and massless particles,
respectively. The solutions of the geodesic equations can be classified
according to the particle's energy and angular momentum, the ratio between the
component of the angular momentum aligned with the axis of the string and the
total angular momentum, the deficit angle of the space-time and as well the
horizon radius (or mass) of the black hole. For bound orbits of massive test
particles we calculate the perihelion shift, we discuss light deflection and
comment on the Newtonian limit.Comment: 21 pages; section 3 shortened, references added; accepted for
publication in Phys. Rev.
Characterization of metal-insulator-semicomductor capacitors with insulating nitride films grown on 4H-SiC
ArticleJAPANESE JOURNAL OF APPLIED PHYSICS. 47(1):676-678(2008)journal articl
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