[en] Objective: This study aimed to evaluate the effects of toxic heavy metal co-exposure on DNA oxidative damage in neonates from a primitive e-waste recycling region, Guiyu town, China. Methods: Our participants included 201 pregnant women: 126 from Guiyu town and 75 from Jinping district of Shantou city, where no e-waste recycling and dismantling activities existed. Structured interview questionnaires were administered to the pregnant women and umbilical cord blood (UCB) samples were collected after delivery. The UCB concentrations of lead, cadmium, chromium, and nickel were analyzed by graphite furnace atomic absorption spectrometry (GFAAS). Levels of UCB plasma 8-hydroxydeoxyguanosine (8-OHdG, a DNA oxidative damage biomarker) were determined by enzyme-linked immunosorbent assay. Results: Our results suggested that UCB lead and cadmium concentrations in neonates of Guiyu were significantly higher than those of Jinping (lead: median 110.45 ng/mL vs. 57.31 ng/mL; cadmium: median 2.50 ng/mL vs. 0.33 ng/mL, both P < 0.001). Parents' residence in Guiyu, and parents' work related to e-waste recycling were the risk factors associated with neonate's UCB lead and cadmium levels. No significant difference of UCB plasma 8-OHdG levels was found between Guiyu and the control area. After adjusting for potential confounders, cord plasma 8-OHdG concentrations (ng/mL) were positively associated with blood cadmium (β = 0.126 ng/mL, 95% CI: 0.055 to 0.198 ng/mL), chromium (β = 0.086 ng/mL, 95% CI: 0.014 to 0.158 ng/mL) and nickel (β = 0.215 ng/mL, 95% CI: 0.113 to 0.317 ng/mL) concentrations. Conclusions: The primitive e-waste recycling and dismantling activities may contribute to the elevated umbilical cord blood toxic heavy metal levels in neonates born in Guiyu. Exposures to cadmium, chromium and nickel were associated with increased oxidative DNA damage in neonates. - Highlights: • DNA oxidative damage levels (8-OHdG) in neonates from Guiyu were assessed. • Neonatal lead, cadmium, chromium, and nickel exposure levels were evaluated. • 8-OHdG levels were positively associated with heavy metal exposures in neonates. • Primitive e-waste recycling resulted in multiple heavy metal exposures in neonates. • Neonatal cadmium, chromium and nickel co-exposure resulted in DNA oxidative damage

[en] By coincidence method, the calibration technique of ZnO:Ga crystal response to single heavy charged particle was established, the waveform response to the single alpha particle was measured, the experiments data were analysed, and the time response to single proton was gained from the plasma time relationship. The results show that the rise time is 324 ps and the FWHM is 686 ps. The ZnO:Ga crystal has a good response to heavy charged particles. It is possible to develop an efficient alpha particle detector for use in a deuterium tritium neutron generator and other new radiation technology. (authors)

[en] High-resolution observations of the solar chromosphere and transition region often reveal surge-like oscillatory activities above sunspot light bridges (LBs). These oscillations are often interpreted as intermittent plasma jets produced by quasi-periodic magnetic reconnection. We have analyzed the oscillations above an LB in a sunspot using data taken by the Interface Region Imaging Spectrograph . The chromospheric 2796 Å images show surge-like activities above the entire LB at any time, forming an oscillating wall. Within the wall we often see that the core of the Mg ii k 2796.35 Å line first experiences a large blueshift, and then gradually decreases to zero shift before increasing to a redshift of comparable magnitude. Such a behavior suggests that the oscillations are highly nonlinear and likely related to shocks. In the 1400 Å passband, which samples emission mainly from the Si iv ion, the most prominent feature is a bright oscillatory front ahead of the surges. We find a positive correlation between the acceleration and maximum velocity of the moving front, which is consistent with numerical simulations of upward propagating slow-mode shock waves. The Si iv 1402.77 Å line profile is generally enhanced and broadened in the bright front, which might be caused by turbulence generated through compression or by the shocks. These results, together with the fact that the oscillation period stays almost unchanged over a long duration, lead us to propose that the surge-like oscillations above LBs are caused by shocked p-mode waves leaked from the underlying photosphere.

[en] Absorption of an photonic configuration with 2D accumulation electron gas is theoretically investigated in the first optical window of biological tissue. The configuration consists of a Bragg mirror, an ITO-dielectric heterostructure and a metal film. Our results show that the configuration can realize perfect absorption (reaches 99.98%) of specific wavelength light at matched electron density of the accumulation electron gas. Moreover, the influences of different parameters on the perfect absorption are investigated, which allows us accurately tune the absorption spectrum of the configuration. In addition, manufacture discrepancies of film thicknesses are simulated through introducing random thickness errors in the configuration. It is found that the discrepancies of film thicknesses dramatically affect the absorption spectrum of the configuration. Fortunately, this manufacture impact can be perfectly remedied by changing the electron density of the accumulation electron gas and the incident angle of light. (paper)

[en] In this paper, properties on pulsed radiation detections of ZnO:Ga crystal grew by a magnetron sputtering method were studied. The time response to pulsed laser, pulsed hard X rays and single α particles, the energy response to pulsed hard X ray, the scintillation efficiency to γ rays, the response to pulsed proton, and the relations of the light intensity varied with the proton energy were measured and analyzed in detail. Results show that the ZnO:Ga crystal has potential applications in the regime of pulse radiation detection .(authors)

[en] Objection: To analyze the imaging appearances of cholesterol pneumonia. Methods We retrospectively analyzed the X-ray and CT findings of 3 patients with cholesterol pneumonia confirmed pathologically and reviewed correlative literature. Results: Lesions similar to mass were found in X-ray and CT imaging of three cases. Two of them appeared cavity with fluid-level and one showed multiple ring enhancement after CT contrast. The course of disease was very. long and it had no respond to antibiotic therapy. Amounts of foam cells rich in cholesterol crystal were detected in pathological examination. Conclusions: Cholesterol pneumonia is a rare chronic pulmonary idiopathic disease, and the radiological findings can do some help to its diagnosis. (authors)

[en] Two-dimensional electron gases (2DEGs) were demonstrated in indium–tin–oxide (ITO)-coated lithium niobate (LN) slabs by monitoring the very first reflection (VFR). Being dictated by light–matter interaction within the half-a-wavelength range, two-fold enhancement of the VFR was observed at one incidence angle, while two-and-half-fold reduction was obtained at another angle, when illuminating a Z-cut ITO–LN slab with two laser beams at 532 nm from the same side. In terms of exponential gain coefficient, such VFR enhancement/reduction corresponds to a range from −7.416 × 10⁴ cm⁻¹ to +4.68 × 10⁴ cm⁻¹, three orders of magnitude higher than that expected from the conventional photorefractive (PR) theory. The nanometer-thick 2DEG and the coupling role played by the evanescent field of the surface plasmon polaritons (SPPs) impose a much looser coherency requirement for the interacting light beams, which was verified by the solid energy coupling observed while rotating the polarization state of one laser beam. As much as 18.4 mW of the side diffraction mode associated with the light track formed on the slab surface, which sheds some light on the dramatic coupling dynamics. All these findings above were far beyond the reach of conventional PR theory, yet well consistent with the physical picture of 2DEG-supported SPPs and their interactions at the ITO–LN interface, offering a good opportunity to conceive and design future photonic/electronic devices for optical modulators. (paper)

[en] The experiment of ZnO:Ga crystal to pulsed proton was performed. The time response to protons and relationship between the luminescence intensity of crystal and the proton energy were obtained. The phenomena and results were analysed. The results show that the crystal has a good response to proton beam,and can be used to detect pulsed neutrons in recoil proton system with fast photodevice. (authors)

[en] An electrochemical sensor based on dual functional Cu²⁺-modified metal–organic framework nanoparticles (Cu²⁺-NMOFs) for sensitive detection of bacterial lipopolysaccharide (LPS) is reported. Cu²⁺-NMOFs were prepared and characterized by SEM, EDS, XRD, and XPS. In this LPS sensor, LPS firstly immobilized in gold nanoparticles/reduced graphene oxide by C18 alkane thiol chains, since the LPS can interact with the C18 alkyl chains by strong intermolecular interactions. Then the Cu²⁺-NMOFs were captured by the anionic groups of the carbohydrate portions of LPS molecules and played a vital role of recognition unit. More importantly, the Cu²⁺-NMOFs can catalyze dopamine oxidation to generate aminochrome, resulting in a strong electrochemical oxidation signal. The electrochemical sensor based on dual functional Cu²⁺-NMOFs was investigated by differential pulse voltammetry, and the stripping peak currents of dopamine oxidized to aminochrome were used to monitor the level of LPS. The developed method demonstrated a wide linear range from 0.0015 to 750 ng/mL with a limit of detection of 6.1 × 10⁻⁴ ng/mL. The fabricated sensor was applied to detect LPS in mouse blood serum and satisfactory results were achieved. Compared to other detection schemes by using the LPS-binding proteins, peptides, and aptamer, the proposed LPS determination based on the catalytic peroxidase-mimicking NMOFs has some advantages such as good reproducibility, low detection limit, and excellent specificity.

[en] Propagation properties of terahertz (THz) waves in a bounded atmospheric-pressure microplasma (AMP) are analyzed in this study. A modified Epstein profile model is used to simulate the electron density distribution caused by the plasma sheaths. By introducing the dielectric constant of a Drude-Lorentz model and using the method of dividing the plasma into a series of subslabs with uniform electron density, the coefficients of power reflection, transmission, and absorption are derived for a bounded microplasma structure. The effects of size of microplasma, electron density profile, and collision frequency on the propagation of THz waves are analyzed numerically. The results indicate that the propagation of THz waves in AMPs depend greatly on the above three parameters. It is demonstrated that the THz wave can play an important role in AMPs diagnostics; meanwhile, the AMP can be used as a novel potential tool to control THz wave propagation.