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Abstract Based on the infinite sum solution of the master equation corresponding to the diffusion channel we derive the law of time evolution of a two-mode squeezed vacuum state in a single-mode (say a -mode) diffusion channel. We find that the squeezing effect decreases, while two different chaotic field modes emerge. After t time period of the diffusion, the a -mode photon number is larger than b -mode photon number by t κ , where κ is the diffusion coefficient, thus by adjusting κ , photon number can controlled. Therefore, the diffusion process can be considered a quantum controlling scheme through photon addition. [ABSTRACT FROM AUTHOR]

Oligodendrocyte apoptosis mediated demyelination is a pathological change characteristic of compressed spinal cord injury (CSCI). However, the mechanism of demyelination due to oligodendrocyte apoptosis is not known. In this study, after successfully establishing a rat CSCI model using a custom-made compressor, we investigated the pathological changes, MBP expression, as well as apoptosis-related protein (p53, active caspase-3) expression to determine whether or not apoptosis and demyelination occurred after injury. To understand the possible mechanism of oligodendrocyte apoptosis, caspase-12 and cytochrome C were analyzed to explore the relationship between oligodendrocyte apoptosis and endoplasmic reticulum(ER)-mitochondria interaction. The transcription factor, E2F1, was also detected by immunofluorescence and Western blot assays. The results showed that CSCI increased the expression levels of p53, E2F1 and active caspase-3 followed by the swelling and breakdown of myelin sheaths. The number of myelinated nerve fibers also decreased with down-regulated expression of MBP. Expression levels of caspase-12 and cytochrome C were enhanced along with a reduction in the number of oligodendrocytes. After treatment of CSCI in rats with Pifithrin-μ(PFT-μ), a specific inhibitor of p53, pathomorphological changes of myelin sheath improved significantly. Expression levels of E2F1, active caspase-3, caspase-12 and cytochrome C were down-regulated, consistent with reduced the number of apoptotic oligodendrocytes. These results demonstrated that over-expression of p53 could mediate oligodendrocyte apoptosis thus resulting in demyelination in two ways; by enhancing ER-mitochondria interaction and by triggering the E2F1 mediated apoptosis pathway. [ABSTRACT FROM AUTHOR]

Abstract: Metal-binding compounds have been shown to have anticancer activity and are being evaluated clinically as anticancer agents. We have recently found that a zinc-binding compound, 5-chloro-7-iodo-8-hydroxyquinoline (clioquinol), kills cancer cells by transporting zinc into the cells. We therefore compared the action of clioquinol with two other cytotoxic zinc-binding compounds, N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) and pyrrolidine dithiocarbamate (PDTC). We demonstrate that metal-binding compounds can be subclassified based upon the reversibility of their cytotoxicity by metal supplementation and their modes of action. Understanding the mechanisms whereby metal-binding compounds affect cell behavior may aid in their optimization for clinical use. [Copyright &y& Elsevier]

• The Yidun arc had a thick crust in the south and a thin crust in the north during the Late Triassic. • Magmas derived from the northern and southern Yidun arc were different in compositions and were associated with different deposit. • Crustal thickness controlled the compositions of magmas and the types of deposit in the Yidun Arc during the Late Triassic. Modern arc-related granitic magmas have variable Sr/Y ratios and metal contents, depending on the thickness of the arc crust on the global scale. However, whether this is true of ancient arcs on a regional scale is still unclear. The Yidun Arc is a Triassic continental arc in Eastern Tibet that has magmatic and mineralization characteristics varying between the northern and southern Yidun Arcs during the Triassic. Several models have been proposed to explain these differences, however, these models are still controversial. To this end, we investigated the petrogenesis of the Late Triassic Xiuwacu intrusion, which is located between the northern and southern Yidun Arcs. The zircon U-Pb dating and Sr-Nd-Hf-O isotopes indicate that the Late Triassic Xiuwacu intrusion was emplaced at 215.6 ± 2.2 Ma and was predominately derived from partial melting of an enriched metastasized mantle combined with amphibole dominated fractionation and a small amount of crustal assimilation. Comparing the Late Triassic Xiuwacu intrusion with other volcanic rocks and intrusions in the Yidun Arc indicates that the Late Triassic Xiuwacu intrusion has a source similar to that of igneous rocks in the southern Yidun Arc. In addition, volcanic rocks and porphyries in the southern Yidun Arc have high Dy/Yb (1.8–2.6, mostly > 2.0) and Sr/Y (24–120) ratios, lack or have slightly negative Eu anomalies, and exhibit calc-alkaline trends, indicating that garnet, amphibole, and magnetite crystalized from their magma source under high pressure. The volcanic rocks in the northern Yidun Arc have low Dy/Yb (1.3–2.2, mostly < 2) and Sr/Y (4–43, mostly < 20) ratios with high negative Eu anomalies and tholeiitic trends, indicating that amphibole and feldspar crystalized predominantly from the source under relatively low pressure. These geochemical features suggest that the crust under the northern Yidun Arc is thin, the crust under the southern Yidun Arc is thick, and the thickness of the crust in the Xiuwacu area is intermediate between them. Several large scale porphyry Cu deposits formed only in the southern Yidun Arc is probably due to the crust of the southern Yidun Arc is thick. The crystallization of amphibole and magnetite reduced the magmas and led to the accumulation of Cu sulfides at the base of the thick southern Yidun Arc at an early stage. Late re-melting of these accumulated Cu sulfides produced these Cu mineralization. The distinct difference in crustal thickness between the northern and southern Yidun arcs is most likely due to the differences in the dip angle of the subducting slab during the Triassic, with these variations controlling magmatism and mineralization. [ABSTRACT FROM AUTHOR]

We study the squeezing-enhanced superposition of coherent states, which are generated by operating a squeezing operator with two parameters on the superposition of coherent states with a different relative phase. The aim of this study is to discuss the nonclassical properties of these novel states by their quantum statistical and squeezing properties. The results show that the squeezing parameter r and relative phase θ play key roles in these states. It is clear to see that these new quantum states have stronger squeezing, antibunching effect, sub-Poissonian distributions behavior when compared to the normal squeezing superposition of coherent states. [ABSTRACT FROM AUTHOR]

Inspired by the dynamical Casimir effect, we construct a new time evolution operator (NTEO). We study the time evolution of the coherent state (TECS) via the NTEO by the technique of integration within an ordered product (IWOP) of operators. We investigate the quantum statistical properties of it, both analytically and numerically, by evaluating its Q-function, second-order correlation function, photon-number distribution and Wigner function. Furthermore, the fidelity between the TECS and the classical coherent state is also given. It is interesting to find that smaller modulation depth can lead to more chance of sub-Poissonian statistics in some cases. It is also shown that the new time evolution operator not only has squeezing effect, but also has rotating effect. [ABSTRACT FROM AUTHOR]

Eight previously undescribed sesquiterpene lactones (1 – 8), together with six known ones (9 – 14) were isolated from the aerial parts of Tithonia diversifolia (Hemsl.) A. Gray. The absolute configurations of these compounds were elucidated using HRMS, NMR spectroscopy, optical rotation measurements, X-ray crystallography, and ECD. Among them, sesquiterpene lactones 2 – 4 share a unique carbon skeleton with a rare C-3/C-4 ring-opened structure. Compounds 1 and 8 showed moderate inhibitory effects toward CT26 murine colon carcinoma cells by promoting lipid ROS production, highlighting their potential as ferroptosis inducers. [Display omitted] • Eight undescribed sesquiterpene lactones were isolated from Tithonia diversifolia. • 2 – 4 were 3,4-seco-sesquiterpene lactones. • 1 and 8 could promote lipid ROS production, acting as new ferroptosis inducers. [ABSTRACT FROM AUTHOR]

The newly-discovered Tongchanggou Mo–Cu porphyry–skarn deposit is located in the southern Yidun Terrane, SE Tibet, with more than 142.5 metric ton resources (0.3 metric ton @ 0.3% Mo, and 34 kt @ 0.8% Cu) hosted in Permian to Triassic strata and Late Cretaceous granodiorite porphyry. Re–Os isotope analyses of molybdenite separates from skarn, granodiorite porphyry and the massive molybdenite orebody yield model ages ranging from 86.8 to 85.2 Ma. LA-ICP-MS U–Pb dating of zircons from the ore-related granodiorite porphyry give 206 Pb/ 238 U ages ranging from 87.4 to 84.2 Ma with a weighted mean 206 Pb/ 238 U age of 84.8 ± 0.3 Ma, indicating a temporal link between granitic magmatism and Mo–Cu mineralization. Geochemically, the ore-related granodiorite porphyries are metaluminous and have an adakite-like signature with relatively low MgO (1.32–1.58 wt%), Cr (5.6–12.9 ppm), Ni (3.79–10.81 ppm), Mg # (43–52) values, and high Sr (304–844 ppm), Sr/Y (21.2–50.8) and La/Yb ratios (37.0–60.1). They also display negative zircon ε Hf (t) values (− 7.4 to − 1.3) and negative whole-rock ε Nd (t) values (− 5.3 to − 4.2), as well as an older Hf–Nd model age, indicating that their magmas were derived from a thickened ancient lower crust within the garnet–amphibolite facies. Partial melting of ancient lower crust generated felsic magmas with high concentrations of Mo that accumulated within the ancient crustal components. Whereas, the copper mineralization is correlated to the remelting of residual sulfide cumulates in subduction-modified lower crust. The Late Cretaceous porphyry Mo–Cu metallogenesis in the southern Yidun Terrane is considered to be related to the transtensional faulting that triggered asthenospheric upwelling beneath the former sulfide-cumulated arc crust. [ABSTRACT FROM AUTHOR]

In this paper, we study the time evolution of the coherent state in a degenerate parametric amplifier by the technique of integration within an ordered product (IWOP) of operators. We investigate some interesting and important physical properties of this state, such as the quantum statistical properties and squeezing effects, both analytically and numerically. Furthermore, the fidelity between this state and the Schrödinger cat state is also given. It is interesting to find that this quantum state has not only squeezing effect, but also rotating effect by appropriately choosing the related parameters. [ABSTRACT FROM AUTHOR]

We solve the master equation with a damped harmonic oscillator and squeezed bath to obtain density operators’ infinite operator–sum representation via a new approach, i.e., by virtue of the new thermo-entangled state representation that has a fictitious mode as a counterpart mode of the system mode. The corresponding Kraus operators from the point of view of quantum channel are also derived. [ABSTRACT FROM AUTHOR]

We propose a new approach for constructing generalized entangled state representation of continuum variables, i.e., we introduce some normally ordered Gaussian-form operators, representing the completeness relation (integration of unity), and the resolution of unity leads to projection operator of entangled state vector whose explicit form in Fock space can be derived. The technique of integration within an ordered product (IWOP) of operators is essential in our discussions. For examples, we derive the entangled state representation for two particles with different masses and a kind of multipartite entangled state representation. [ABSTRACT FROM AUTHOR]

We derive some new generating function formulas of Jacobi polynomials in the context of quantum optics theory, i.e., by virtue of the photon subtracted and photon added two-mode squeezed states. [ABSTRACT FROM AUTHOR]

Abstract: The spectroscopic properties of the Dy3+:LiLa(MoO4)2 crystal prepared by the Czochralski method, have been investigated so as to assess its potentialities for direct yellow laser operation upon excitation with blue–violet or near UV laser diodes. Optical absorption, excitation, emission and fluorescence decay measurements have been performed at room temperature. An intense yellow emission band with favorably high yellow-to-blue luminescence intensity ratio has been observed in the visible region, and relevant parameters for laser applications have been determined in accordance with the Judd–Ofelt theory and Füchtbauer–Ladenburg formula. Based on analysis of Dy3+ concentration dependence of fluorescence lifetime, the energy transfer among Dy3+ ions by the dipole–dipole interaction has been found to be responsible for the fluorescence self-quenching of the 4F9/2 upper laser level at higher dopant concentration. The prospect of the Dy3+:LiLa(MoO4)2 crystal for the realization of efficient yellow laser systems has been discussed. [Copyright &y& Elsevier]

Abstract: The spectroscopic properties of Dy3+:LiGd(MoO4)2 crystal have been investigated with aim to assess the feasibility of laser operation in the yellow region. On the basis of the analysis of polarized absorption spectra in the framework of the Judd–Ofelt theory, the main spectroscopic characteristics relevant for laser applications have been determined. An intense yellow emission band corresponding to the 4F9/2 → 6H13/2 transition around 575nm has been observed in the visible region. The emission cross-sections for the 4F9/2 → 6H13/2 transition have been calculated using the Füchtbauer–Ladenburg formula. The fluorescence and radiative lifetimes of the 4F9/2 manifold are equal to 139.0μs and 199.1μs, respectively, and the quantum efficiency is 69.8%. [Copyright &y& Elsevier]

Abstract: One-dimensional semiconductor materials Bi2Te3 nanotubes were synthesized via an ultrasonic-assisted hydrothermal method at 180°C for 48h. The products were characterized by XRD, SEM, EDS, TEM, and HRTEM. The results indicate the size of as-prepared Bi2Te3 nanotubes is about 500–1000nm in length and 50–100nm in diameter. Bi2Te3 nanotubes grow spirally along the (001) direction, whose angle with the tube axis is about 20°. The probable formation model of Bi2Te3 nanotubes is proposed based on the experimental results. The synthetic approach could be used to synthesize other one-dimensional nanomaterials. [Copyright &y& Elsevier]