Optical bistability and multistability via quantum coherence in chiral molecules.

The optical bistability (OB) and multistability (OM) in chiral molecules are investigated by placing the sample into a unidirectional ring cavity. Because of broken mirror symmetry of the effective potential, the chiral molecules have a cyclic three-level Δ-configuration structure, in which one- and two-photon transitions can coexist. We find that the OB is achievable in this system on exact one-, two- and three-photon resonance conditions but absent in the three-level Λ-type system under the two-photon resonance. Moreover, the OM and the switching between OB and OM are also realized by choosing parameters properly. Interestingly, the left- and right-handed chiral molecules exhibit different bistable and multistable behaviors. It is shown that the threshold intensity of OB is strongly dependent on the percentage of the two enantiomers in the mixture. This provides an effective approach to probe molecular chirality and to determine enantiomer excess, which may find potential application in organic chemistry, pharmacology, biochemistry, etc..

In vivo assessment of the effect of taxifolin glycoside on atopic dermatitis-like skin lesions using biomedical tools in NC/Nga mice.

BACKGROUND: Noninvasive methods of assessment are widely used in clinical trials. However, such methods have not been established in atopic dermatitis (AD), which is a chronic inflammatory skin disease. AIM: To demonstrate, using biomedical tools, the benefits of a new substance, taxifolin glycoside (TAX), in an AD model, the NC/Nga mouse. METHODS: We evaluated the efficacy of topical TAX for AD by measuring clinical skin severity score, cytokine expression and serum IgE level, and by using biomedical measures (vapometry and corneometry). Topical TAX was applied to AD-induced NC/Nga mice for 3 weeks. The anti-inflammatory effects of this compound were demonstrated noninvasively using biomedical tools and immunological assays. RESULTS: Our method of AD assessment using biomedical tools is more objective and accurate than visual inspection. The results obtained using the biomedical tools were identical to those obtained using immunological assays. CONCLUSIONS: In vivo biomedical tools are useful for diagnosing and monitoring treatment effects in AD.

Vascular endothelial growth factor -634 G/C polymorphism and risk of cancer: an updated meta-analysis.

The association between vascular endothelial growth factor (VEGF) gene polymorphisms and risk of cancer has been investigated in several studies published previously; however, the individual results are inconclusive. Therefore, we performed a meta-analysis to establish evidence for an association between the VEGF -634 G/C polymorphism and risk of cancer. We searched PubMed, Medline, and Korean Studies Information Service System databases and identified 29 case-control studies, containing data of 25,324 individuals, for this meta-analysis. The odds ratio (OR) and 95% confidence interval (95%CI) were used to determine the strength of the association. Overall, no significant association was detected in the allele model (G allele vs C allele, OR = 0.98, 95%CI = 0.93-1.03), dominant model (G/G+G/C vs C/C, OR = 1.00, 95%CI = 0.90-1.11), or recessive model (G/G vs G/C+C/C, OR = 0.96, 95%CI = 0.89-1.03). The meta-analysis results suggest that the VEGF -634 G/C polymorphism may not be related to the development of cancer. However, additional studies with larger sample size are required in order to provide supporting evidence.

Test of genuine multipartite nonlocality without inequalities.

In this Letter we propose a set of conditions on the joint probabilities as a test of genuine multipartite nonlocality without inequality. Our test is failed by all nonsignaling local models in which even nonlocal correlations among some observables (not all) are allowed as long as these correlations respect the nonsignaling principle. A pass of our test by a state therefore indicates that this state cannot be simulated by any nonsignaling local models; i.e., the state exhibits genuine multipartite nonlocality. It turns out that all entangled symmetric n-qubit (n≥3) states pass our test and therefore are n-way nonlocal. Also we construct two Bell-type inequalities from our proposed test whose violations indicate genuine multipartite nonlocal correlations.

Severity of acute and chronic urticaria correlates with D-dimer level, but not C-reactive protein or total IgE.

BACKGROUND: Although various scoring systems for measuring urticaria severity have been introduced, most rely on subjective criteria. Therefore, additional objective criteria such as laboratory markers would be helpful adjuncts in making this assessment. AIM: To evaluate the usefulness of three laboratory markers [D-dimer, C-reactive protein (CRP), and total IgE] in assessing disease severity of both acute urticaria (AU) and chronic urticaria (CU). METHODS: We conducted a retrospective analysis of 94 patients with urticaria. Correlations between the aforementioned laboratory markers and the Urticaria Activity Score (UAS) were calculated. RESULTS: A substantial proportion of patients with urticaria (acute 43.5%; chronic 39.6%) had an increased D-dimer level. Additionally, there was a significant correlation between D-dimer level and UAS (AU r = 0.60, P < 0.001; CU r = 0.37, P < 0.05). However, there was no significant correlation between UAS and either CRP or total IgE. CONCLUSIONS: D-dimer level could be used as a marker of disease severity for both AU and CU. However, CRP and total IgE are not as reliable in predicting disease severity.

Detecting and estimating continuous-variable entanglement by local orthogonal observables.

Entanglement detection and estimation are fundamental problems in quantum information science. Compared with discrete-variable states, for which lots of efficient entanglement detection criteria and lower bounds of entanglement measures have been proposed, the continuous-variable entanglement is much less understood. Here we shall present a family of entanglement witnesses based on continuous-variable local orthogonal observables (CVLOOs) to detect and estimate entanglement of Gaussian and non-Gaussian states, especially for bound entangled states. By choosing an optimal set of CVLOOs, our entanglement witness is equivalent to the realignment criterion and can be used to detect bound entanglement of a class of 2+2 mode Gaussian states. Via our entanglement witness, lower bounds of two typical entanglement measures for arbitrary two-mode continuous-variable states are provided.

Intrinsic dynamical fluctuation assisted symmetry breaking in adiabatic following.

Classical adiabatic invariants in actual adiabatic processes possess intrinsic dynamical fluctuations. The magnitude of such intrinsic fluctuations is often thought to be negligible. This widely believed physical picture is contested here. For adiabatic following of a moving stable fixed-point solution facing a pitchfork bifurcation, we show that intrinsic dynamical fluctuations in an adiabatic process can assist in a deterministic selection between two symmetry-connected fixed-point solutions, with the outcome independent of the duration of the adiabatic process. Using a classical model Hamiltonian also relevant to a two-mode quantum system, we further demonstrate the formation of an adiabatic hysteresis loop in purely Hamiltonian mechanics and the generation of a Berry phase via changing one single-valued parameter only.

Greenberger-Horne-Zeilinger paradoxes from qudit graph states.

One fascinating way of revealing quantum nonlocality is the all-versus-nothing test due to Greenberger, Horne, and Zeilinger (GHZ) known as the GHZ paradox. So far genuine multipartite and multilevel GHZ paradoxes are known to exist only in systems containing an odd number of particles. Here we shall construct GHZ paradoxes for an arbitrary number (greater than 3) of particles with the help of qudit graph states on a special kind of graphs, called GHZ graphs. Furthermore, based on the GHZ paradox arising from a GHZ graph, we derive a Bell inequality with two d-outcome observables for each observer, whose maximal violation attained by the corresponding graph state, and a Kochen-Specker inequality testing the quantum contextuality in a state-independent fashion.

Strongly interacting photons in asymmetric quantum well via resonant tunneling.

We propose an asymmetric quantum well structure to realize strong interaction between two slow optical pulses. The essential idea is the combination of the advantages of inverted-Y type scheme and resonant tunneling. We analytically demonstrate that giant cross-Kerr nonlinearity can be achieved with vanishing absorptions. Owing to resonant tunneling, the contributions of the probe and signal cross-Kerr nonlinearities to total nonlinear phase shift vary from destructive to constrictive, leading to nonlinear phase shift on order of π at low light level. In this structure, the scheme is inherent symmetric for the probe and signal pulses. Consequently, the condition of group velocity matching can be fulfilled with appropriate initial electron distribution.

State-independent proof of Kochen-Specker theorem with 13 rays.

Quantum contextuality, as proved by Kochen and Specker, and also by Bell, should manifest itself in any state in any system with more than two distinguishable states and recently has been experimentally verified. However, for the simplest system capable of exhibiting contextuality, a qutrit, the quantum contextuality is verified only state dependently in experiment because too many (at least 31) observables are involved in all the known state-independent tests. Here we report an experimentally testable inequality involving only 13 observables that is satisfied by all noncontextual realistic models while being violated by all qutrit states. Thus our inequality facilitates a state-independent test of the quantum contextuality for an indivisible quantum system. We also provide a record-breaking state-independent proof of the Kochen-Specker theorem with 13 directions determined by 26 points on the surface of a magic cube.

All entangled pure states violate a single Bell's inequality.

We show that a single Bell's inequality with two dichotomic observables for each observer, which originates from Hardy's nonlocality proof without inequalities, is violated by all entangled pure states of a given number of particles, each of which may have a different number of energy levels. Thus Gisin's theorem is proved in its most general form from which it follows that for pure states Bell's nonlocality and quantum entanglement are equivalent.

Fault-tolerant Greenberger-Horne-Zeilinger paradox based on non-Abelian anyons.

We propose a scheme to test the Greenberger-Horne-Zeilinger paradox based on braidings of non-Abelian anyons, which are exotic quasiparticle excitations of topological states of matter. Because topological ordered states are robust against local perturbations, this scheme is in some sense "fault-tolerant" and might close the detection inefficiency loophole problem in previous experimental tests of the Greenberger-Horne-Zeilinger paradox. In turn, the construction of the Greenberger-Horne-Zeilinger paradox reveals the nonlocal property of non-Abelian anyons. Our results indicate that the non-Abelian fractional statistics is a pure quantum effect and cannot be described by local realistic theories. Finally, we present a possible experimental implementation of the scheme based on the anyonic interferometry technologies.

Geometric entangling gates in decoherence-free subspaces with minimal requirements.

We introduce a new strongly driven dispersive atom-cavity interaction and develop a new scheme for implementing the nontrivial entangling gates for two logical qubits in decoherence-free subspaces (DFSs). Our scheme combines the robust advantages of DFS and the geometric phase. Moreover, only two neighboring physical qubits, which encode a logical qubit, are required to undergo the collective dephasing in our scheme.

Congenital Bednar's tumour.

Bednar's tumour (BT) is a rare variant of dermatofibrosarcoma protuberans (DFSP). In addition to the typical histological findings of DFSP, melanin-containing dendritic cells are found in BT. Its occurrence at birth is very rare and there have been only two case reports of congenital BT in the English literature. A 12-year-old boy presented with a single, dome-shaped erythematous nodule, 25 x 15 mm in size, on the lower back. The lesion was present as a depressed patch at birth. Subsequently the lesion grew gradually to a dome-shaped mass. Histopathological examination found a dense infiltration of spindle cells arranged in a storiform pattern in the dermis, with pigmented cells admixed with the spindle cells. Cell mitosis and atypia were rarely seen. On immunohistochemical study, the tumour cells were positive for CD34 and melanin-containing cells were positive for S-100. A diagnosis of BT was made and the mass was removed by wide local excision. There was no evidence of recurrence at follow-up 8 months later.

Receptor guided 3D-QSAR: a useful approach for designing of IGF-1R inhibitors.

Research by other investigators has established that insulin-like growth factor-1 receptor (IGF-1R) is a key oncological target, and that derivatives of 1, 3-disubstituted-imidazo[1,5-alpha] pyrazine are potent IGF-1R inhibitors. In this paper, we report on our three-dimensional quantitative structure activity relationship (3D-QSAR) studies for this series of compounds. We validated the 3D-QSAR models by the comparison of two major alignment schemes, namely, ligand-based (LB) and receptor-guided (RG) alignment schemes. The latter scheme yielded better 3D-QSAR models for both comparative molecular field analysis (CoMFA) (q(2) = 0.35, r(2) = 0.95) and comparative molecular similarity indices analysis (CoMSIA) (q(2) = 0.51, r(2) = 0.86). We submit that this might arise from the more accurate inhibitor alignment that results from using the structural information of the active site. We conclude that the receptor-guided 3D-QSAR may be helpful to design more potent IGF-1R inhibitors, as well as to understand their binding affinity with the receptor.

Interregional correlations of glucose metabolism between the basal ganglia and different cortical areas: an ultra-high resolution PET/MRI fusion study using 18F-FDG.

Basal ganglia have complex functional connections with the cerebral cortex and are involved in motor control, executive functions of the forebrain, such as the planning of movement, and cognitive behaviors based on their connections. The aim of this study was to provide detailed functional correlation patterns between the basal ganglia and cerebral cortex by conducting an interregional correlation analysis of the 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) data based on precise structural information. Fifteen participants were scanned with 7-Tesla magnetic resonance imaging (MRI) and high resolution research tomography (HRRT)-PET fusion system using 18F-FDG. For detailed interregional correlation analysis, 24 subregions of the basal ganglia including pre-commissural dorsal caudate, post-commissural caudate, pre-commissural dorsal putamen, post-commissural putamen, internal globus pallidus, and external globus pallidus and 80 cerebral regions were selected as regions of interest on the MRI image and their glucose metabolism were calculated from the PET images. Pearson's product-moment correlation analysis was conducted for the interregional correlation analysis of the basal ganglia. Functional correlation patterns between the basal ganglia and cerebral cortex were not only consistent with the findings of previous studies, but also showed new functional correlation between the dorsal striatum (i.e., caudate nucleus and putamen) and insula. In this study, we established the detailed basal ganglia subregional functional correlation patterns using 18F-FDG PET/MRI fusion imaging. Our methods and results could potentially be an important resource for investigating basal ganglia dysfunction as well as for conducting functional studies in the context of movement and psychiatric disorders.

Synthesis and biological evaluation of 1beta-methylcarbapenems having cyclic thiourea moieties and their related compounds.

The synthesis of a new series of 1beta-methylcarbapenems having cyclic thiourea moieties is described. Their in vitro antibacterial activities against both Gram-positive and Gram-negative bacteria were tested and the effect of substituent on the pyrrolidine ring was investigated. A particular compound (IIId) having piperazine thiourea moiety showed the most potent antibacterial activity.

Synthesis and in vitro activity of a series 1beta-methylcarbapenem derivatives.

The synthesis of a new series of 1beta-methylcarbapenems having pyrrolidine and piperidine moieties is described. Their in vitro antibacterial activities against both Gram-positive and Gram-negative bacteria were tested and the effect of substituent on the pyrrolidine ring was investigated. A particular compound (IIIb) having hydroxypyrrolidine moiety showed the most potent antibacterial activity.

Effect of weak measurement on entanglement distribution over noisy channels.

Being able to implement effective entanglement distribution in noisy environments is a key step towards practical quantum communication, and long-term efforts have been made on the development of it. Recently, it has been found that the null-result weak measurement (NRWM) can be used to enhance probabilistically the entanglement of a single copy of amplitude-damped entangled state. This paper investigates remote distributions of bipartite and multipartite entangled states in the amplitudedamping environment by combining NRWMs and entanglement distillation protocols (EDPs). We show that the NRWM has no positive effect on the distribution of bipartite maximally entangled states and multipartite Greenberger-Horne-Zeilinger states, although it is able to increase the amount of entanglement of each source state (noisy entangled state) of EDPs with a certain probability. However, we find that the NRWM would contribute to remote distributions of multipartite W states. We demonstrate that the NRWM can not only reduce the fidelity thresholds for distillability of decohered W states, but also raise the distillation efficiencies of W states. Our results suggest a new idea for quantifying the ability of a local filtering operation in protecting entanglement from decoherence.