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High harmonics of circular polarization can be directly generated by monochromatic circularly polarized incident light owing to the high density and stable structure of crystal media. If the arrangement of multiple coplanar atoms in the unit structure of the crystal exhibits rotational symmetry, the polarization state of the high harmonics generated from the crystal follows specific selection rules that have been observed in the 2D crystal medium. In addition, the geometric symmetry of the coplanar atom distribution is related to the orientation of cubic crystals. This implies that only the polarization along a specific crystal orientation can achieve a selection of high‐harmonic polarization states. However, this is a very weak process in cubic crystals owing to the attenuation of crystal anisotropy to circularly polarized light and the dependence of the electron transition rate on the crystal orientation. In this study, plasmonic nanoantennas are designed on silicon crystal films to enhance this process. The harmonic emission is more than ten times brighter than that without nanoantennas and conformed to the selection rules for high harmonics. The research results offer a new approach for deep­ultraviolet space filtering, carrier control, and the development of compact extreme­ultraviolet light sources. [ABSTRACT FROM AUTHOR]

Three‐coil inductive power transfer (IPT) charging system can not only achieve inherent constant current (CC) to constant voltage (CV) transition but also tolerate load open‐circuit. However, due to the cross‐coupling between the auxiliary coil and the receiver coil, the output voltage in CV mode may deviate from the CV voltage significantly, which makes the design freedom of the three‐coil coupler low. By replacing the auxiliary coil with a transformer, an improved auxiliary circuit is proposed in this paper to address the cross‐coupling issue and to increase the design freedom of the loosely coupled transformer (LCT). The improved auxiliary circuit can achieve load short‐circuit and open‐circuit protection. Besides, the optimization design of LCT is easy to achieve by load impedance matching. The operating principle and parameters design of the improved auxiliary circuit are discussed. A 1 kW experimental prototype is built to verify the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

Summary: Due to the merits of convenience and flexibility, inductive power transfer (IPT) systems have become popular for energy storage devices, such as lithium‐ion batteries, which require constant current (CC) and constant voltage (CV) outputs. The conventional LCC‐LCC topology with high design freedom is widely used for battery charging. The conventional LCC‐LCC topology achieves the initial CC output and the subsequent CV output by reconfiguring its topology or hopping its operating frequency, which increases the control complexity. This paper proposes a reconstructed LCC‐LCC compensated IPT system, which can achieve the inherent CC‐to‐CV transition without extra components and control methods. Compared with the conventional LCC‐LCC topology having CC and CV outputs, the operating frequency and topology of the proposed IPT system are fixed. Besides, the battery state of charge (SOC) detection and wireless communication are not required. The analysis and parameters design of the proposed IPT system is performed. Finally, an experimental prototype of the proposed IPT system with 48 V input and 72 V/2 A output is built to validate the proposal. [ABSTRACT FROM AUTHOR]

Background: Co‐expression of multiple genes in single vectors has achieved varying degrees of success by employing two promoters and/or application of viral 2A‐peptide or the internal ribosome entry‐site (IRES). However, promoter interference, potential functional‐interruption of expressed‐proteins by 2A‐generated residual peptides or weaker translation of IRES‐mediated downstream genes has curtailed their utilization. Thus, there is the need for single vectors that robustly express multiple proteins for enhanced gene therapy applications. Methods: We engineered lentiviral‐vectors for dual‐cassette expression of green fluorescent protein and mCherry in uni‐ or bidirectional architectures using the short‐version (Es) of elongation factor 1α (EF) promoter and simian virus 40 promoter (Sv). The regulatory function of a core fragment (cC) from human cytomegalovirus promoter was investigated with cell‐lineage specificity in NIH3T3 (fibroblast) and hematopoietic cell lines U937 (monocyte/macrophage), LCL (lymphoid), DAMI (megakaryocyte) and MEL (erythroid). Results: The cC element in reverse‐orientation not only boosted upstream Es promoter to levels comparable to full‐length EF in DAMI, U937 and 3T3 cells, but also blocked the suppression of downstream Sv promoter by Es in U937 and 3T3 cells with further improved Sv activity in DAMI cells. Such lineage‐restricted up‐regulation is likely attributed to two protein‐binding domains of cC and diverse expression of related factors in different cell types for enhancer and terminator activities, but not spacing function. Conclusions: Such a newly developed dual‐cassette vector could be advantageous, particularly in hematopoietic cell‐mediated gene/cancer therapy, by allowing for independent and robust co‐expression of therapeutic gene(s) and/or a selectable gene or imaging marker in the same cells. [ABSTRACT FROM AUTHOR]

An ultrafast spectral imaging optical system featuring adaptive precompensation for group delay dispersion, automated tuning and collimation, rapid power stabilization, and rapid spectral imaging switching is developed. In this system, real‐time visualization ensures that the excited Gaussian beam remains focused on the nanoarray of the electron‐beam lithographed metasurface, as well as maximum gain of the nonlinear effect information. Based on the system, two surface‐lattice resonance metasurfaces under broadly tunable excitation (800–1300 nm) are investigated. The results demonstrated a 16‐fold enhancement in the third harmonic generation intensity and a 168‐fold enhancement in the second harmonic generation intensity at a 1200 nm excitation compared to the unpatterned films, with a narrow resonant bandwidth of 8 nm. This can be attributed to the frequency‐matching lattice‐enhanced localized surface plasmon resonance, which results in effective and vast excitation of plasmons that produce numerous energetic carriers. The method offers the possibility to reveal various ultrafast dynamics in nonlinear plasmonic metasurfaces. [ABSTRACT FROM AUTHOR]

Metastasis associated 1 protein (MTA1) is one of the prime facilitators of metastatic progression in all solid tumors including hepatocellular carcinoma (HCC). However, the underlying regulatory mechanism of MTA1 expression in HCC is not clear. In this study, we evaluated MTA1 transcript and protein expression in HCC and normal hepatic cell lines. The results revealed that MTA1 protein expression had a significantly increase in HCC cell line, HuH6, compared with that in normal hepatic cell line, THLE-2. Determination of protein half-life using cycloheximide (CHX) treatment did not reveal any statistically significant difference in protein turn-over rates between THLE-2 (3.3 ± 0.25 h) and HuH6 (3.6 ± 0.15 h) cell lines. MTA1 protein level was stabilized in THLE-2 cells after treatment with MG-132 to levels similar to those observed in HuH6 cells. Mass spectrometric analysis of FLAG immunoprecipitates of FLAG- MTA1 transfected THLE-2 cells after MG-132 treated revealed candidate ubiquitin ligases that were interacting with MTA1. RNAi-mediated silencing of each prospective ubiquitin ligase in THLE-2 cells indicated that knockdown of TRIM25 resulted in stabilization of MTA1 protein, indicating TRIM25 as a putative E3 ligase for MTA1. Coimmunoprecipitation of FLAG-tagged MTA1, but not IgG, in MG-132 treated and untreated THLE-2 cells cotransfected with either FLAG- MTA1 or Myc- TRIM25 revealed robust polyubiquitinated MTA1, confirming that the TRIM25 is the ubiquitin ligase for MTA1 degradation. Overexpression of TRIM25 in HuH6 and RNAi mediated silencing of TRIM25 in THLE-2 cells inhibited and increased the cell migration and invasion, respectively. Analysis of The Cancer Genome Atlas data for assessment of TRIM25 transcript level and MTA1 protein expression in 25 HCC patients confirmed an inverse correlation between the expression of TRIM25 and MTA1. Cumulatively, our data reveal a novel mechanism of post-translational to regulate MTA1 expression in normal hepatic cells, which is repressed in HCC. © 2017 IUBMB Life, 69(10):795-801, 2017 [ABSTRACT FROM AUTHOR]

In this study, we investigate the microstructure and formation of segregated silicon nanocrystals (nc-Si) from annealed Si-rich Si xN/Si yN multilayers. It is found the nc-Si are separated and arranged in every sublayer with two different grain sizes. Through XPS and Raman analysis, it is discovered that Si atoms diffuse from the Si yN sublayers with smaller nc-Si to the Si xN sublayers with larger nc-Si during annealing. Meanwhile, the grain size of Si xN sublayers increase and that of Si yN sublayers decrease, compared to single layer sample. It is suggested that the atomic diffusion with grain size change phenomenon is ascribed to coalescence-like growth followed by Ostwald ripening process, which eventually results in Si atoms transport from small Si clusters in Si yN sublayers to large Si cluster in Si xN sublayers and forms the segregated nc-Si multilayers. This work gives us better understanding of the nc-Si growth and atomic diffusion in annealed Si-rich multilayers. [ABSTRACT FROM AUTHOR]

Objective: To explore the effects of 30 Gy of (60)Co γ-rays on apoptosis and reactive oxygen species (ROS) levels in minipig parotid cells as a possible mechanism for radiation-induced parotid injury.Study Design: Experimental study.Setting: Department of Radiotherapy, First Affiliated Hospital, Guangxi Medical University, Nanning, China.Subjects and Methods: Forty male minipigs were divided into control and irradiated groups. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling was used for detecting apoptosis in the parotid cells, immunohistochemistry, and western blots were used to test expression of the B-cell lymphoma 2 (Bcl-2) and BCL2-associated X (Bax) proteins, and reverse transcription polymerase chain reaction was used to analyze the expression of Bcl-2, Bax, p53, and caspase-3 messenger ribonucleic acid. An enzyme-linked immunosorbent assay was used to detect ROS levels in the parotid tissue.Results: At each time point, the apoptotic rates in the irradiated group were higher than those in the control group. Furthermore, the ROS and expression levels of Bax, p53, and caspase-3 messenger ribonucleic acid and proteins gradually increased and were higher than those in the control group. Conversely, the expression of Bcl-2 was decreased in the irradiated group (P < .05).Conclusions: Ionizing radiation induces the production of ROS and promotes changes in the expression of several apoptotic proteins, which increases apoptosis and likely contributes to the mechanism of radiation-induced parotid injury. [ABSTRACT FROM AUTHOR]

Eighteen polymorphic microsatellite loci from the giant mottled eel ( Anguilla marmorata) were identified and their characteristics were described. These markers were tested in two wild populations from China ( n = 20) and Australia ( n = 20) respectively. The number of alleles ranged from 9 to 14 with an average of 11.28 per locus. The mean expected heterozygosity ( HE) was 0.8696 in the population from China, 0.8823 in the population from Australia. No locus deviates significantly from Hardy–Weinberg proportions ( P < 0.05). [ABSTRACT FROM AUTHOR]

The preparation of a series of novel homopolymers and copolymers containing bisazobenzene chromophores with side‐on structure in the side chains via atom transfer radical polymerization (ATRP) were presented. UV–vis spectra of the thin films of these polymers under irradiation of 488 nm Ar+ laser suggested that the photoisomerization of the bisazobenzene chromophores happened mainly on one of the two azo groups in the bisazobenzene chromophores with similar probability due to their side‐on structure. Good photoalignment behaviors of these polymers were proved by photoinduced birefringence measurements because side‐on structure permitted the two azo groups in the bisazobenzene chromophores both participated in the trans–cis–trans photoisomerization cycles equally to induce the whole chromophore reorientation. Furthermore, the reorientation axis located at the middle of chromophore decreased the sweep volume during photoalignment. The impetus for this study was to evaluate the photoisomerization and photoalignment process of side‐on bisazobenzene‐containing polymers and to find possible applications in the photosensitive devices. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3460–3472, 2007 [ABSTRACT FROM AUTHOR]

ABSTRACT Two isomeric homoleptic Ir(III) complexes with pyridinopyridazine derivative ligands were prepared first. Due to its stronger intramolecular hydrogen bonding and intermolecular interactions, complex IrPPM has a higher decomposition temperature (5% weight loss) of 387°C than IrPPP (354°C). They have similar UV–Vis absorption and photoluminescence spectra in CH2Cl2 solution with photoluminescence peaks around 635–636 nm. However, the emission peak of IrPPM in neat powder obviously red‐shifted to 652 nm, and that of IrPPP blue‐shifted to 626 nm. Simultaneously, complex IrPPM has a lower photoluminescence quantum yield of 0.3 than IrPPP (0.5). Efficient saturated red OLED devices are developed with Commission Internationale de L'Eclairage color coordinates of (0.67, 0.32) and (0.66, 0.32), respectively. The maximum external quantum efficiencies of both devices exceed 11%. These results demonstrate the great potential of pyridinopyridazine derivatives for developing new iridium complexes for OLED applications. [ABSTRACT FROM AUTHOR]

Metal-coated fiber Bragg grating (MFBG) sensor was proposed to measure high-temperature and high-pressure condition. Metal-coated layer of FBG improved bonding performance between metal material substrate and sensor protected as well as prolonged the lifespan of the FBG sensor. By optimized and designed thin-wall copper cylinder structure and soldered MFBG on this, we had measured high-temperature and high-pressure environments. This sensor can measure the pressure range from 0 to 40 MPa. Its correlative coefficient reached 99.95% and its sensitivity was 0.0493 nm/MPa, which was about 19 times than normal Fiber Bragg Grating. Using a thermostat, a good linearity of temperature characteristic of this structure was obtained and its correlative coefficient reached 99.904%. Temperature had been measured range from 50 to 240°C. Considering FBG intrinsic advantage, it has been applied in harsh environments such as oil-well. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1138–1140, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23319 [ABSTRACT FROM AUTHOR]