3,687 research outputs found
Correct path-integral formulation of quantum thermal field theory in coherent-state representation
The path-integral quantization of thermal scalar, vector and spinor fields is
performed newly in the coherent-state representation. In doing this, we choose
the thermal electrodynamics and theory as examples. By this
quantization, correct expressions of the partition functions and the generating
functionals for the quantum thermal electrodynamics and theory are
obtained in the coherent-state representation. These expressions allow us to
perform analytical calculations of the partition functions and generating
functionals and therefore are useful in practical applications. Especially, the
perturbative expansions of the generating functionals are derived specifically
by virtue of the stationary-phase method. The generating functionals formulated
in the position space are re-derived from the ones given in the coherent-state
representation
JAK2V617F promotes replication fork stalling with disease-restricted impairment of the intra-S checkpoint response
Cancers result from the accumulation of genetic lesions, but the cellular consequences of driver mutations remain unclear, especially during the earliest stages of malignancy. The V617F mutation in the JAK2 non-receptor tyrosine kinase (JAK2V617F) is present as an early somatic event in most patients with myeloproliferative neoplasms (MPNs), and the study of these chronic myeloid malignancies provides an experimentally tractable approach to understanding early tumorigenesis. Introduction of exogenous JAK2V617F impairs replication fork progression and is associated with activation of the intra-S checkpoint, with both effects mediated by phosphatidylinositide 3-kinase (PI3K) signaling. Analysis of clonally derived JAK2V617F-positive erythroblasts from MPN patients also demonstrated impaired replication fork progression accompanied by increased levels of replication protein A (RPA)-containing foci. However, the associated intra-S checkpoint response was impaired in erythroblasts from polycythemia vera (PV) patients, but not in those from essential thrombocythemia (ET) patients. Moreover, inhibition of p53 in PV erythroblasts resulted in more gamma-H2Ax (γ-H2Ax)–marked double-stranded breaks compared with in like-treated ET erythroblasts, suggesting the defective intra-S checkpoint function seen in PV increases DNA damage in the context of attenuated p53 signaling. These results demonstrate oncogene-induced impairment of replication fork progression in primary cells from MPN patients, reveal unexpected disease-restricted differences in activation of the intra-S checkpoint, and have potential implications for the clonal evolution of malignancies
Plasma Magnetosphere Formation Around Oscillating Magnetized Neutron Stars
The notion of death line of rotating pulsars is applied to model of
oscillating neutron stars. It is shown that the magnetosphere of typical
non-rotating oscillating stars may not contain secondary plasma to support the
generation of radio emission in the region of open field lines of plasma
magnetosphere.Comment: Accepted for publication in Astrophysics & Space Scienc
Multivariate side-band subtraction using probabilistic event weights
A common situation in experimental physics is to have a signal which can not
be separated from a non-interfering background through the use of any cut. In
this paper, we describe a procedure for determining, on an event-by-event
basis, a quality factor (-factor) that a given event originated from the
signal distribution. This procedure generalizes the "side-band" subtraction
method to higher dimensions without requiring the data to be divided into bins.
The -factors can then be used as event weights in subsequent analysis
procedures, allowing one to more directly access the true spectrum of the
signal.Comment: 17 pages, 9 figure
Isovector and isoscalar superfluid phases in rotating nuclei
The subtle interplay between the two nuclear superfluids, isovector T=1 and
isoscalar T=0 phases, are investigated in an exactly soluble model. It is shown
that T=1 and T=0 pair-modes decouple in the exact calculations with the T=1
pair-energy being independent of the T=0 pair-strength and vice-versa. In the
rotating-field, the isoscalar correlations remain constant in contrast to the
well known quenching of isovector pairing. An increase of the isoscalar (J=1,
T=0) pair-field results in a delay of the bandcrossing frequency. This
behaviour is shown to be present only near the N=Z line and its experimental
confirmation would imply a strong signature for isoscalar pairing collectivity.
The solutions of the exact model are also discussed in the
Hartree-Fock-Bogoliubov approximation.Comment: 5 pages, 4 figures, submitted to PR
Rapid analysis of pyrethroid insecticides in aquaculture seawater samples via membrane-assisted solvent extraction coupled with gas chromatography-electron capture detection
A simple, efficient, and environmentally friendly membrane-assisted solvent extraction (MASE) method for the extraction and preconcentration of six pyrethroid insecticides from aquaculture seawater samples followed by gas chromatography-electron capture detection (GC-ECD) was successfully proposed. The operating conditions for MASE, such as the extraction solvent, solvent volume, NaCl concentration, stirring rate, extraction time, and temperature, were optimized. Compared to conventional Florisil-solid phase extraction (SPE), higher extraction recoveries (85.9% to 105.9%) of three spiked levels of the six pyrethroid pesticides in aquaculture seawater were obtained using MASE, and the RSD values were lower than 7.9%. The limits of detection (LOD, signal-to-noise ratio (S/N)=3) and quantification (LOQ, S/N = 10) were in the range of 0.037–0.166 and 0.12–0.55 µg L-1, respectively. The results demonstrate the excellent applicability of the MASE method in analyzing the six pyrethroid pesticides in aqueous samples. The proposed method exhibited a high potential for routine monitoring analysis of pyrethroid insecticides in seawater samples
STAT1 activation in association with JAK2 exon 12 mutations
La inclusión de la perspectiva de género en la actividad jurisdiccional es una demanda sostenida de los colectivos feministas y de mujeres, dado que las sentencias tienen un poder performativo y envían un mensaje a la sociedad: “[…] tienen un poder individual y colectivo que impactan en la vida de las personas y conforman la identidad del poder judicial como un actor imprescindible en la construcción de un Estado democrático de derecho” (Suprema Corte de Justicia de la Nación, 2013:7). La incorporación de la perspectiva de género viene a garantizar la igualdad de posiciones (Kessler, 2014) entre mujeres y varones como una meta, trascendiendo la mera igualdad de oportunidades que hasta el presente se ha demostrado insuficiente para que las mujeres consigamos una ciudadanía plena. Al momento de incorporar la perspectiva de género en las sentencias, quienes juzgan deben tener presente en primer lugar, el impacto diferenciado de las normas en base al sexo de las personas. En segundo lugar, la interpretación y aplicación de las leyes en relación con (y en base a) estereotipos de género. Si, por ejemplo, quienes imparten justicia no tienen presentes los estereotipos de género vigentes detrás de las violaciones a los derechos humanos de las mujeres, si no los detectan ni cuestionan, entonces los reproducen. Tal como sostiene Scott (1996) el género es una categoría imprescindible para el análisis social. En tercer lugar, al momento del juzgamiento, se deben tener en cuenta las exclusiones legitimadas por la ley por pensar el mundo en términos binarios y androcéntricos; en cuarto lugar, la distribución no equitativa de recursos y poder que opera entre varones y mujeres en el marco de una organización social patriarcal, y, por último, el trato diferenciado por género legitimado por las propias leyes.Eje 3: Tramas violentas y espacios de exclusión.Instituto de Cultura Jurídic
Application of semidefinite programming to maximize the spectral gap produced by node removal
The smallest positive eigenvalue of the Laplacian of a network is called the
spectral gap and characterizes various dynamics on networks. We propose
mathematical programming methods to maximize the spectral gap of a given
network by removing a fixed number of nodes. We formulate relaxed versions of
the original problem using semidefinite programming and apply them to example
networks.Comment: 1 figure. Short paper presented in CompleNet, Berlin, March 13-15
(2013
The orbifold cohomology of moduli of genus 3 curves
In this work we study the additive orbifold cohomology of the moduli stack of
smooth genus g curves. We show that this problem reduces to investigating the
rational cohomology of moduli spaces of cyclic covers of curves where the genus
of the covering curve is g. Then we work out the case of genus g=3.
Furthermore, we determine the part of the orbifold cohomology of the
Deligne-Mumford compactification of the moduli space of genus 3 curves that
comes from the Zariski closure of the inertia stack of M_3.Comment: 29 pages, 2 figures. Minor changes, to appear in Manuscripta Mat
Study of f_0(980) and f_0(1500) from B_s \to f_0(980)\pi, f_0(1500)\pi Decays
In this paper, we analyze the scalar mesons and from
the decays within Perturbative
QCD approach. From the leading order calculations, we find that (a) in the
allowed mixing angle ranges, the branching ratio of is about , which is smaller than
that of (the difference is a few times even one
order); (b) the decay is better to distinguish
between the lowest lying state or the first excited state for ,
because the branching ratios for two scenarios have about one-order difference
in most of the mixing angle ranges; and (c) the direct CP asymmetries of for two scenarios also exists great difference. In
scenario II, the variation range of the value according to the mixing angle is very small, except for
the values corresponding to the mixing angles being near or
, while the variation range of in scenario I is very large. Compared with the future data for
the decay , it is ease to determine the nature
of the scalar meson .Comment: 16 pages, 3 figures, Revte
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