2,036 research outputs found
Recombining Plasma & Gamma-ray Emission in the Mixed-morphology Supernova Remnant 3C 400.2
3C 400.2 belongs to the mixed morphology supernova remnant class, showing
center-filled X-ray and shell-like radio morphology. We present a study of 3C
400.2 with archival Suzaku and Fermi-LAT observations. We find recombining
plasma (RP) in the Suzaku spectra of north-east and south-east regions. The
spectra of these regions are well described by two-component thermal plasma
models: The hard component is in RP, while the soft component is in collisional
ionization equilibrium (CIE) conditions. The RP has enhanced abundances
indicating that the X-ray emission has an ejecta origin, while the CIE has
solar abundances associated with the interstellar material. The X-ray spectra
of north-west and south-west regions are best fitted by a two-component thermal
plasma model: an ionizing and a CIE plasma. We have detected GeV gamma-ray
emission from 3C 400.2 at the level of 5 assuming a point-like
source model with a power-law (PL) type spectrum. We have also detected a new
GeV source at the level of 13 assuming a Gaussian extension model
with a PL type spectrum in the neighborhood of the SNR. We report the analysis
results of 3C 400.2 and the new extended gamma-ray source and discuss the
nature of gamma-ray emission of 3C 400.2 in the context of existing NANTEN CO
data, DRAO HI data, and the Suzaku X-ray analysis results.Comment: Accepted to be published in the Astrophysical Journa
The Superconformal Gaugings in Three Dimensions
We show how three-dimensional superconformal theories for any number N <= 8
of supersymmetries can be obtained by taking a conformal limit of the
corresponding three-dimensional gauged supergravity models. The superconformal
theories are characterized by an embedding tensor that satisfies a linear and
quadratic constraint. We analyze these constraints and give the general
solutions for all cases. We find new N = 4,5 superconformal theories based on
the exceptional Lie superalgebras F(4), G(3) and D(2|1;\alpha). Using the
supergravity connection we discuss which massive deformations to expect. As an
example we work out the details for the case of N = 6 supersymmetry.Comment: 22 pages; v2: refs. added, minor corrections, version published in
JHE
Definition of the Ethical Values and Ethics Codes for Turkish Midwifery: A Focused Group Study in Kocaeli
Background: The independent roles of midwives have not been properly defined, and midwifery ethical values and moral codes proper to Turkish culture have not been developed. The absence of legal regulations concerning midwifery has negatively affected midwifery in the process of professionalization.
Objectives: The purpose of this study was to identify the professional values of midwifery in Turkey.
Materials and Methods: A focus group was created with the participation of nine midwives working at two state hospitals and a university hospital that provide birth service for women in Kocaeli, which is the most important industrial city in Turkey. The opinions of the midwives on the characteristics that a good midwife should possess and the professional values that a good midwife should observe were collected via in-depth interviews. The interviews were recorded. A total of three meetings were held with the participants. Finally, the notes taken by the reporter during these interviews were rearranged, and the recordings were transcribed by the researchers.
Results: The characteristics suggested by the participants were classified into three categories: professional, personal, and interpersonal. Professional competence, capacity to properly inform interested parties, trustworthiness, respect for individuals and human dignity, and empathy were the most commonly named characteristics. As for the professional values of midwifery, professional competence, trustworthiness, responsibility, maximum benefit, and protection of privacy were the most often identified. Midwives also reported that most of the difficulties they faced in the exercise of daily tasks concerned protecting the privacy of their patients as well as the integrity and prestige of the profession, achieving the maximum benefit and least harm for patients, and providing a just and equal service.
Conclusions: The professional values were mentioned by participant midwives were similar to the values proposed by international professional organizations. But there were some differences perhaps due to cultural differences
Blood transfusion improves renal oxygenation and renal function in sepsis-induced acute kidney injury in rats
Background: The effects of blood transfusion on renal microcirculation during sepsis are unknown. This study aimed to investigate the effect of blood transfusion on renal microvascular oxygenation and renal function during sepsis-induced acute kidney injury. Methods: Twenty-seven Wistar albino rats were randomized into four groups: a sham group (n = 6), a lipopolysaccharide (LPS) group (n = 7), a LPS group that received fluid resuscitation (n = 7), and a LPS group that received blood transfusion (n = 7). The mean arterial blood pressure, renal blood flow, and renal microvascular oxygenation within the kidney cortex were recorded. Acute kidney injury was assessed using the serum creatinine levels, metabolic cost, and histopathological lesions. Nitrosative stress (expression of endothelial (eNOS) and inducible nitric oxide synthase (iNOS)) within the kidney was assessed by immunohistochemistry. Hemoglobin levels, pH, serum lactate levels, and liver enzymes were measured. Results: Fluid resuscitation and blood transfusion both significantly improved the mean arterial pressure and renal blood flow after LPS infusion. Renal microvascular oxygenation, serum creatinine levels, and tubular damage significantly improved in the LPS group that received blood transfusion compared to the group that received fluids. Moreover, the renal expression of eNOS was markedly suppressed under endotoxin challenge. Blood transfusion, but not fluid resuscitation, was able to restore the renal expression of eNOS. However, there were no significant differences in lactic acidosis or liver function between the two groups. Conclusions: Blood transfusion significantly improved renal function in endotoxemic rats. The specific beneficial effect of blood transfusion on the kidney could have been mediated in part by the improvements in r
Cooperative Effect of miR-141-3p and miR-145-5p in the Regulation of Targets in Clear Cell Renal Cell Carcinoma
Background Due to the poor prognosis for advanced renal cell carcinoma (RCC),
there is an urgent need for new therapeutic targets and for prognostic markers
to identify high risk tumors. MicroRNAs (miRNAs) are frequently dysregulated
in tumors, play a crucial role during carcinogenesis and therefore might be
promising new biomarkers. In previous studies, we identified miR-141-3p and
miR-145-5p to be downregulated in clear cell RCC (ccRCC). Our objective was to
investigate the functional association of these miRNAs, focusing on the
cooperative regulation of new specific targets and their role in ccRCC
progression. Methods The effect of miR-141-3p and miR-145-5p on cell migration
was examined by overexpression in 786-O cells. New targets of both miRNAs were
identified by miRWalk, validated in 786-O and ACHN cells and additionally
characterized in ccRCC tissue on mRNA and protein level. Results In functional
analysis, a tumor suppressive effect of miR-141-3p and miR-145-5p by
decreasing migration and invasion of RCC cells could be shown. Furthermore,
co-overexpression of the miRNAs seemed to result in an increased inhibition of
cell migration. Both miRNAs were recognized as post-transcriptional regulators
of the targets EAPP, HS6ST2, LOX, TGFB2 and VRK2. Additionally, they showed a
cooperative effect again as demonstrated by a significantly increased
inhibition of HS6ST2 and LOX expression after simultaneous overexpression of
both miRNAs. In ccRCC tissue, LOX mRNA expression was strongly increased
compared to normal tissue, allowing also to distinguish between non-metastatic
and already metastasized primary tumors. Finally, in subsequent tissue
microarray analysis LOX protein expression showed a prognostic relevance for
the overall survival of ccRCC patients. Conclusion These results illustrate a
jointly strengthening effect of the dysregulated miR-141-3p and miR-145-5p in
various tumor associated processes. Focusing on the cooperative effect of
miRNAs provides new opportunities for the development of therapeutic
strategies and offers novel prognostic and diagnostic capabilities
Holography in 4D (Super) Higher Spin Theories and a Test via Cubic Scalar Couplings
The correspondences proposed previously between higher spin gauge theories
and free singleton field theories were recently extended into a more complete
picture by Klebanov and Polyakov in the case of the minimal bosonic theory in
D=4 to include the strongly coupled fixed point of the 3d O(N) vector model.
Here we propose an N=1 supersymmetric version of this picture. We also
elaborate on the role of parity in constraining the bulk interactions, and in
distinguishing two minimal bosonic models obtained as two different consistent
truncations of the minimal N=1 model that retain the scalar or the
pseudo-scalar field. We refer to these models as the Type A and Type B models,
respectively, and conjecture that the latter is holographically dual to the 3d
Gross-Neveu model. In the case of the Type A model, we show the vanishing of
the three-scalar amplitude with regular boundary conditions. This agrees with
the O(N) vector model computation of Petkou, thereby providing a non-trivial
test of the Klebanov-Polyakov conjecture.Comment: 30p
Macroscopic invisibility cloaking of visible light
Invisibility cloaks, which used to be confined to the realm of fiction, have now been turned into a scientific reality thanks to the enabling theoretical tools of transformation optics and conformal mapping. Inspired by those theoretical works, the experimental realization of electromagnetic invisibility cloaks has been reported at various electromagnetic frequencies. All the invisibility cloaks demonstrated thus far, however, have relied on nano- or micro-fabricated artificial composite materials with spatially varying electromagnetic properties, which limit the size of the cloaked region to a few wavelengths. Here, we report the first realization of a macroscopic volumetric invisibility cloak constructed from natural birefringent crystals. The cloak operates at visible frequencies and is capable of hiding, for a specific light polarization, three-dimensional objects of the scale of centimetres and millimetres. Our work opens avenues for future applications with macroscopic cloaking devices
Witten-Nester Energy in Topologically Massive Gravity
We formulate topologically massive supergravity with cosmological constant in
the first order formalism, and construct the Noether supercurrent and
superpotential associated with its local supersymmetry. Using these results, we
construct in ordinary topologically massive gravity the Witten-Nester integral
for conserved charges containing spinors which satisfy a generalized version of
Witten equation on the initial value surface. We show that the Witten-Nester
charge, represented as an integral over the boundary of the initial value
surface produces the Abbott-Deser-Tekin energy for asymptotically anti de
Sitter spacetimes. We consider all values of the Chern-Simons coupling
constant, including the critical value known as the chiral point, and study the
cases of standard Brown-Henneaux boundary conditions, as well as their weaker
version that allow a slower fall-off. Studying the Witten-Nester energy as a
bulk integral over the initial value surface instead, we find a bound on the
energy, and through it the sufficient condition for the positivity of the
energy. In particular, we find that spacetimes of Petrov type N that admit
globally well defined solutions of the generalized Witten equation have
positive energy.Comment: 43 page
On Critical Massive (Super)Gravity in adS3
We review the status of three-dimensional "general massive gravity" (GMG) in
its linearization about an anti-de Sitter (adS) vacuum, focusing on critical
points in parameter space that yield generalizations of "chiral gravity". We
then show how these results extend to N=1 super-GMG, expanded about a
supersymmetric adS vacuum, and also to the most general `curvature-squared' N=1
supergravity model.Comment: 10 pages, Proceedings of ERE 2010, Granada, 6-10 september 2010;
reference adde
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