281 research outputs found
Counterfactuality of "counterfactual" communication
The counterfactuality of the recently proposed protocols for direct quantum
communication is analyzed. It is argued that the protocols can be
counterfactual only for one value of the transmitted bit. The protocols achieve
a reduced probability of detection of the particle in the transmission channel
by increasing the number of paths in the channel. However, this probability is
not lower than the probability of detecting a particle actually passing through
such a multi-path channel, which was found to be surprisingly small. The
relation between security and counterfactuality of the protocols is discussed.
An analysis of counterfactuality of the protocols in the framework of the
Bohmian interpretation is performed.Comment: Critical analysis of arXiv:1206.2042 and Phys. Rev. A 89, 052334.
Revised according to comments of several referees, accepted for publication
in J. Phys.
Flexible and Asymmetric Ligand in Constructing Coordinated Complexes: Synthesis, Crystal Structures and Fluorescent Characterization
Flexible and asymmetric ligand L [L = 1-((pyridin-3-yl)methyl)-1H-benzotriazole], is used as a basic backbone to construct complicated metal-organic frameworks. Two new polymers, namely, [Ag2(L)2(NO3)2]n (1) and [Ag(L)(ClO4)]n (2), were synthesized and characterized by X-ray structure analysis and fluorescent spectroscopy. The complex 1 gives an âSâ type double helical conformation, whereas complex 2 exhibits a 1D zigzag configuration. Different anions affect the silver coordination geometry and crystal packing topology
Pioglitazone Improves Mitochondrial Function in the Remnant Kidney and Protects against Renal Fibrosis in 5/6 Nephrectomized Rats
Pioglitazone is a type of peroxisome proliferator-activated receptor Îł (PPARÎł) agonist and has been demonstrated to be effective in chronic kidney diseases (CKD) treatment. However, the underlying mechanism involved in the renoprotection of pioglitazone has not been fully revealed. In the present study, the renoprotective mechanism of pioglitazone was investigated in 5/6 nephrectomized (Nx) rats and TGF-ÎČ1-exposed HK-2 cells. Pioglitazone attenuated renal injury and improved renal function, as examined by 24 h urinary protein, blood urea nitrogen and plasma creatinine in Nx rats. Renal fibrosis and enhanced expressions of profibrotic proteins TGF-ÎČ1, fibronectin and collagen I caused by Nx were significantly alleviated by pioglitazone. In addition, pioglitazone protected mitochondrial functions by stabilizing the mitochondrial membrane potential, inhibiting ROS generation, maintaining ATP production and the activities of complexes I and III, and preventing cytochrome C leakage from mitochondria. Pioglitazone also upregulated the expression levels of ATP synthase ÎČ, COX I and NDUFB8, which were downregulated in the kidney of Nx rats and TGF-ÎČ1-exposed HK-2 cells. Furthermore, pioglitazone increased fusion proteins Opa-1 and Mfn2 expressions and decreased fission protein Drp1 expression. The results imply that pioglitazone may exert the renoprotective effects through modulating mitochondrial electron transport chain and mitochondrial dynamics in CKD. Finally, these recoveries were completely or partly inhibited by GW9662, which suggests that these effects at least partly PPARÎł dependent. This study provides evidence for the pharmacological mechanism of pioglitazone in the treatment of CKD
Collective Modes and Raman Scattering in One Dimensional Electron Systems
In this paper, we review recent development in the theory of resonant
inelastic light (Raman) scattering in one-dimensional electron systems. The
particular systems we have in mind are electron doped GaAs based semiconductor
quantum wire nanostructures, although the theory can be easily modified to
apply to other one-dimensional systems. We compare the traditional
conduction-band-based non-resonant theories with the full resonant theories
including the effects of interband transitions. We find that resonance is
essential in explaining the experimental data in which the single particle
excitations have finite spectral weights comparable to the collective charge
density excitations. Using several different theoretical models (Fermi liquid
model, Luttinger liquid model, and Hubbard model) and reasonable
approximations, we further demonstrate that the ubiquitously observed strong
single particle excitations in the experimental Raman spectra cannot be
explained by the spinless multi-spinon excitations in the Luttinger liquid
description. The observability of distinct Luttinger liquid features in the
Raman scattering spectroscopy is critically discussed.Comment: A review to be published in the special issue of Solid State
Communications on one-dimensional system
A comparison of perceived uselessness between centenarians and non-centenarians in China
Abstract Background Self-perceived uselessness is associated with poorer health in older adults. However, it is unclear whether there is a difference in self-perceived uselessness between centenarians and non-centenarians, and if so, which factors contributed to the difference. Methods We used four waves of a nationwide longitudinal dataset from 2005 to 2014 in China to investigate these research goals. We first performed multinomial logit regression models to examine the risk of the high or moderate frequency of self-perceived uselessness relative to the low frequency among centenarians (5778 persons) in comparison with non-centenarians aged 65â99 (20,846 persons). We then conducted a cohort analysis for those born in 1906â1913, examining differences in self-perceived uselessness between those centenarians and those died between ages 91 and 99 during 2005â2014. Results Compared to persons aged 65â79, centenarians had 84% (relative risk ratio (RRR)â=â1.84, 95% CI:1.69â2.01) and 35% (RRRâ=â1.35, 95% CI: 1.25â1.46) higher risk to have the high frequency and the moderate frequency of feeling useless versus low frequency, respectively, when only demographic factors were controlled for. However, centenarians had 31% (RRRâ=â0.69, 95% CI: 0.54â0.88), 43% (RRRâ=â0.57, 95% CI: 0.49â0.68), and 25% (RRRâ=â0.75, 95% CI: 0.67â0.83) lower risk, respectively, to have the high frequency of self-perceived uselessness relative to the low frequency when a wide set of study covariates were controlled for. In the case of the moderate versus the low frequency of self-perceived uselessness, the corresponding figures were 18% (RRRâ=â0.82, 95% CI: 0.66â1.02), 22% (RRRâ=â0.78, 95%CI: 0.67â0.90), and 13% (RRRâ=â0.87, 95% CI: 0.79â0.96), respectively. The cohort analysis further indicates that those who became centenarians were 36â39% less likely than those died at ages 91â94 to report the high and the moderate frequencies of self-perceived uselessness versus the low frequency; no difference was found between centenarians and those died at ages 95â99. In both period and cohort analyses, behavioral and health-related factors affected the perception substantially. Conclusions Overall, centenarians were less likely to perceive themselves as useless compared to non-centenarians of younger birth cohorts when a wide set of covariates were considered and non-centenarians of the same birth cohort. How centenarians manage to do so remains an open question. Our findings may help improve our understanding about the longevity secrets of centenarians
Characterization of amoxicillinâ and clavulanic acidâspecific T cells in patients with amoxicillinâclavulanateâinduced liver injury
Drugâinduced liver injury (DILI) frequently has a delayed onset with several human leukocyte antigen (HLA) genotypes affecting susceptibility, indicating a potential role for the adaptive immune system in the disease. The aim of this study was to investigate whether drugâresponsive T lymphocytes are detectable in patients who developed DILI with the combination, antimicrobial amoxicillinâclavulanate. Lymphocytes from 6 of 7 patients were found to proliferate and/or secrete interferonâgamma (IFNâÎł) when cultured with amoxicillin and/or clavulanic acid. Amoxicillin (nâ=â105) and clavulanic acid (nâ=â16) responsive CD4+ and CD8+ Tâcell clones expressing CCR, chemokine (CâC motif) receptor 4, CCR9, and chemokine (CâXâC motif) receptor 3 were generated from patients with and without HLA risk alleles; no crossâreactivity was observed between the two drug antigens. Amoxicillin clones were found to secrete a heterogeneous panel of mediators, including IFNâÎł, interleukinâ22 and cytolytic molecules. In contrast, cytokine secretion by the clavulanic acid clones was more restricted. CD4+ and CD8+ clones were major histocompatability complex class II and I restricted, respectively, with the drug antigen being presented to CD4+ clones in the context of HLAâDR molecules. Several pieces of evidence indicate that the clones were activated by a hapten mechanism: First, professional antigenâpresenting cells (APCs) were required for optimal activation; second, pulsing APCs for 4â16 hours activated the clones; and third, inhibition of processing abrogated the proliferative response and cytokine release. Conclusion: Both amoxicillinâ and clavulanic acidâspecific T cells participate in the liver injury that develops in certain patients exposed to amoxicillinâclavulanate. (Hepatology 2015;62:887â899
The impact of human EGFR kinase domain mutations on lung tumorigenesis and in vivo sensitivity to EGFR-targeted therapies
SummaryTo understand the role of human epidermal growth factor receptor (hEGFR) kinase domain mutations in lung tumorigenesis and response to EGFR-targeted therapies, we generated bitransgenic mice with inducible expression in type II pneumocytes of two common hEGFR mutants seen in human lung cancer. Both bitransgenic lines developed lung adenocarcinoma after sustained hEGFR mutant expression, confirming their oncogenic potential. Maintenance of these lung tumors was dependent on continued expression of the EGFR mutants. Treatment with small molecule inhibitors (erlotinib or HKI-272) as well as prolonged treatment with a humanized anti-hEGFR antibody (cetuximab) led to dramatic tumor regression. These data suggest that persistent EGFR signaling is required for tumor maintenance in human lung adenocarcinomas expressing EGFR mutants
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