149 research outputs found
A Two-Step Quantum Direct Communication Protocol Using Einstein-Podolsky-Rosen Pair Block
A protocol for quantum secure direct communication using blocks of EPR pairs
is proposed. A set of ordered EPR pairs is used as a data block for sending
secret message directly. The ordered EPR set is divided into two particle
sequences, a checking sequence and a message-coding sequence. After
transmitting the checking sequence, the two parties of communication check
eavesdropping by measuring a fraction of particles randomly chosen, with random
choice of two sets of measuring bases. After insuring the security of the
quantum channel, the sender, Alice encodes the secret message directly on the
message-coding sequence and send them to Bob. By combining the checking and
message-coding sequences together, Bob is able to read out the encoded messages
directly. The scheme is secure because an eavesdropper cannot get both
sequences simultaneously. We also discuss issues in a noisy channel.Comment: 8 pages and 2 figures. To appear in Phys Rev
Accounting for Slow J/psi from B Decay
A slow J/psi excess exists in the inclusive B -> J/psi+X spectrum, and is
indicative of some hadronic effect. From color octet nature of c cbar pair in
b-> c cbar s decay, one such possibility would be B -> J/psi+ K_g decay, where
K_g is a hybrid resonance with sbar g q constituents. We show that a K_g
resonance of ~ 2 GeV mass and suitably broad width could be behind the excess.Comment: 4 pages, 2 figures. To appear in Phys. Rev.
How do full-service carriers and low-cost carriers passengers perceived service dimensions, passengers’ satisfaction, and loyalty differently? An empirical study
Purpose: In this study, group differences between full-service carriers (FSC) and low-cost carriers (LCC) in loyalty constructs are investigated, revealing the relationship between service quality and loyalty. This work focuses on five dimensions, including tangibility, empathy, assurance, responsiveness, and reliability, constitute service quality. Design/methodology/approach: 248 questionnaires were collected in the first half of 2019. The antecedents of customer loyalty are explored, and the group differences between FSC and LCC are analyzed. For assessing the path model with the consideration of group variance, the Partial Least Squares Multiple Group Analysis (PLS-MGA) was adopted to analyze the differences of the estimated inter-group coefficient. Findings: Our findings suggest that service assurance, service empathy, and service reliability positively impact the value perceived. The impact of service empathy on customer satisfaction in FSC is significantly diverse from LCC. Several suggestions are provided to FSC and LCC on improving their services in view of passengers’ wants and interests. Originality/value: With the data collected at the HKIA, this study examined the relationships among service quality, perceived value, customer satisfaction, and customer loyalty and divided service quality into five dimensions. The findings show that assurance, empathy, and reliability of service quality positively affect the value perceived, and the effects of responsiveness and tangibility of service quality on perceived value are insignificant. Among the five aspects of service quality, assurance, reliability, responsiveness, and tangibility of the service quality are the pre-conditions of customer satisfaction. However, only the reliability of service is the antecedent of customer loyalty. Besides, the value perceived positively affects customers to be satisfactory and loyal. Furthermore, satisfaction degree also significantly influences the degree of customers’ loyalty. As to the role of airline types, the sole effect is on customers' satisfaction is service empathy, with a significant difference between FSC and LCCPeer Reviewe
A reduction of unilateral ureteral obstruction-induced renal fibrosis by a therapy combining valsartan with aliskiren
Wu WP, Chang CH, Chiu YT, Ku CL, Wen MC, Shu KH, Wu MJ. A reduction of unilateral ureteral obstruction-induced renal fibrosis by a therapy combining valsartan with aliskiren. Am J Physiol Renal Physiol 299: F929-F941, 2010. First published August 4, 2010; doi:10.1152/ajprenal.00192.2010.-The protective effect of combination therapy with valsartan and aliskiren against renal fibrosis remains to be defined. This study was undertaken to examine the protective effects of the combination of valsartan and aliskiren against renal fibrosis induced by unilateral ureteral obstruction (UUO). Combination therapy with valsartan (15 mg . kg(-1) . day(-1)) and aliskiren (10 mg . kg(-1) . day(-1)), valsartan monotherapy (30 mg . kg(-1) . day(-1)), and aliskiren monotherapy (20 mg . kg(-1) . day(-1)) all significantly ameliorated the increase in blood urea nitrogen and the degree of hydronephrosis determined by the increase in weight and length of the obstructed kidney. The dose titration study and blood pressure measurement confirmed that the combination therapy provided a greater benefit independent of the vasodilatory effect. There were no significant changes in serum levels of creatinine, sodium, and potassium in UUO rats and any treatment groups. Combination therapy also attenuated UUO-related increases in the scores of tubular dilatation, interstitial volume, interstitial collagen deposition, alpha-smooth muscle actin, the activation of ERK 1/2, the infiltration of monocytes/macrophages, the mRNA expression of snail-1, and transforming growth factor-beta 1 to a greater extent compared with aliskiren or valsartan used alone. The mRNA expression of renin and the (pro) renin receptor significantly increased after UUO. Combination therapy and monotherapy of valsartan and aliskiren had a comparable enhancing effect on the mRNA expression of renin, whereas all these treatments did not affect the expression of the (pro) renin receptor. In conclusion, a direct renin inhibitor in conjunction with an angiotensin II receptor blocker exerts increased renal protection against renal fibrosis and inflammation during obstruction over either agent alone
Effect of aristolochic acid on intracellular calcium concentration and its links with apoptosis in renal tubular cells
Aristolochic acid (AA) has been demonstrated to play a causal role in Chinese herbs nephropathy. However, the detailed mechanism for AA to induce apoptosis of renal tubular cells remains obscure. In this study, we show that AA evokes a rapid rise in the intracellular Ca2+ concentration of renal tubular cells through release of intracellular endoplasmic reticulum Ca2+ stores and influx of extracellular Ca2+, which in turn causes endoplasmic reticulum stress and mitochondria stress, resulting in activation of caspases and finally apoptosis. Ca2+ antagonists, including calbindin-D-28k (an intracellular Ca2+ buffering protein) and BAPTA-AM (a cell-permeable Ca2+ chelator), are capable of ameliorating endoplasmic reticulum stress and mitochondria stress, and thereby enhance the resistance of the cells to AA. Moreover, we show that overexpression of the anti-apoptotic protein Bcl-2 in combination with BAPTA-AM treatment can provide renal tubular cells with almost full protection against AA-induced cytotoxicity. In conclusion, our results demonstrate an impact of AA to intracellular Ca2+ concentration and its link with AA-induced cytotoxicity
Manganites at Quarter Filling: Role of Jahn-Teller Interactions
We have analyzed different correlation functions in a realistic spin-orbital
model for half-doped manganites. Using a finite-temperature diagonalization
technique the CE phase was found in the charge-ordered phase in the case of
small antiferromagnetic interactions between electrons. It is shown
that a key ingredient responsible for stabilization of the CE-type spin and
orbital-ordered state is the cooperative Jahn-Teller (JT) interaction between
next-nearest Mn neighbors mediated by the breathing mode distortion of
Mn octahedra and displacements of Mn ions. The topological phase
factor in the Mn-Mn hopping leading to gap formation in one-dimensional models
for the CE phase as well as the nearest neighbor JT coupling are not able to
produce the zigzag chains typical for the CE phase in our model.Comment: 16 pages with 16 figures, contains a more detailed parameter estimate
based on the structural data by Radaelli et al. (accepted for publication in
Phys. Rev. B
Hepatocyte Nuclear Factor 4-Alpha Is Essential for the Active Epigenetic State at Enhancers in Mouse Liver
Theory and Applications of Non-Relativistic and Relativistic Turbulent Reconnection
Realistic astrophysical environments are turbulent due to the extremely high
Reynolds numbers. Therefore, the theories of reconnection intended for
describing astrophysical reconnection should not ignore the effects of
turbulence on magnetic reconnection. Turbulence is known to change the nature
of many physical processes dramatically and in this review we claim that
magnetic reconnection is not an exception. We stress that not only
astrophysical turbulence is ubiquitous, but also magnetic reconnection itself
induces turbulence. Thus turbulence must be accounted for in any realistic
astrophysical reconnection setup. We argue that due to the similarities of MHD
turbulence in relativistic and non-relativistic cases the theory of magnetic
reconnection developed for the non-relativistic case can be extended to the
relativistic case and we provide numerical simulations that support this
conjecture. We also provide quantitative comparisons of the theoretical
predictions and results of numerical experiments, including the situations when
turbulent reconnection is self-driven, i.e. the turbulence in the system is
generated by the reconnection process itself. We show how turbulent
reconnection entails the violation of magnetic flux freezing, the conclusion
that has really far reaching consequences for many realistically turbulent
astrophysical environments. In addition, we consider observational testing of
turbulent reconnection as well as numerous implications of the theory. The
former includes the Sun and solar wind reconnection, while the latter include
the process of reconnection diffusion induced by turbulent reconnection, the
acceleration of energetic particles, bursts of turbulent reconnection related
to black hole sources as well as gamma ray bursts. Finally, we explain why
turbulent reconnection cannot be explained by turbulent resistivity or derived
through the mean field approach.Comment: 66 pages, 24 figures, a chapter of the book "Magnetic Reconnection -
Concepts and Applications", editors W. Gonzalez, E. N. Parke
FGF receptor genes and breast cancer susceptibility: results from the Breast Cancer Association Consortium
Background:Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium.
Methods:Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression.
Results:Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95 confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2.
Conclusion:Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2. © 2014 Cancer Research UK
Various correlations in a Heisenberg XXZ spin chain both in thermal equilibrium and under the intrinsic decoherence
In this paper we discuss various correlations measured by the concurrence
(C), classical correlation (CC), quantum discord (QD), and geometric measure of
discord (GMD) in a two-qubit Heisenberg XXZ spin chain in the presence of
external magnetic field and Dzyaloshinskii-Moriya (DM) anisotropic
antisymmetric interaction. Based on the analytically derived expressions for
the correlations for the cases of thermal equilibrium and the inclusion of
intrinsic decoherence, we discuss and compare the effects of various system
parameters on the correlations in different cases. The results show that the
anisotropy Jz is considerably crucial for the correlations in thermal
equilibrium at zero temperature limit but ineffective under the consideration
of the intrinsic decoherence, and these quantities decrease as temperature T
rises on the whole. Besides, J turned out to be constructive, but B be
detrimental in the manipulation and control of various quantities both in
thermal equilibrium and under the intrinsic decoherence which can be avoided by
tuning other system parameters, while D is constructive in thermal equilibrium,
but destructive in the case of intrinsic decoherence in general. In addition,
for the initial state , all
the correlations except the CC, exhibit a damping oscillation to a stable value
larger than zero following the time, while for the initial state , all the correlations monotonously
decrease, but CC still remains maximum. Moreover, there is not a definite
ordering of these quantities in thermal equilibrium, whereas there is a
descending order of the CC, C, GMD and QD under the intrinsic decoherence with
a nonnull B when the initial state is .Comment: 8 pages, 7 figure
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