Unveiling the Structural Origins of Dynamic Diversity in Pd-Based Metallic Glasses.

The ß-relaxation is one of the major dynamic behaviors in metallic glasses (MGs) and exhibits diverse features. Despite decades of efforts, the understanding of its structural origin and contribution to the overall dynamics of MG systems is still unclear. Here two palladium-based Pd─Cu─P and Pd─Ni─P MGs are reported with distinct different ß-relaxation behaviors and reveal the structural origins for the difference using the advanced X-ray photon correlation spectroscopy and absorption fine structure techniques together with the first-principles calculations. The pronounced ß-relaxation and fast atomic dynamics in the Pd─Cu─P MG mainly come from the strong mobility of Cu atoms and their locally favored structures. In contrast, the motion of Ni atoms is constrained by P atoms in the Pd─Ni─P MG, leading to the weakened ß-relaxation peak and sluggish dynamics. The correlation of atomic dynamics with microscopic structures provides a way to understand the structural origins of different dynamic behaviors as well as the nature of aging in disordered materials.

High throughput fabrication of large-area plasmonic color filters by soft-X-ray interference lithography.

Plasmonic color filters in mass production have been restricted from current fabrication technology, which impede their applications. Soft-X-ray interference lithography (XIL) has recently generated considerable interest as a newly developed technique for the production of periodic nano-structures with resolution theoretically below 4 nm. Here we ameliorate XIL by adding an order sorting aperture and designing the light path properly to achieve perfect-stitching nano-patterns and fast fabrication of large-area color filters. The fill factor of nanostructures prepared on ultrathin Ag films can largely affect the transmission minimum of plasmonic color filters. By changing the fill factor, the color can be controlled flexibly, improving the utilization efficiency of the mask in XIL simultaneously. The calculated data agree well with the experimental results. Finally, an underlying mechanism has been uncovered after systematically analyzing the localized surface plasmon polaritons (LSPPs) coupling in electric field distribution.

Angle-insensitive plasmonic color filters with randomly distributed silver nanodisks.

Plasmonic color filters inherently suffer from angular sensitiveness, which hinder them from practical applications. Here, we present a plasmonic subtractive color filter incorporating two-dimensional randomly distributed silver nanodisks on top of a glass substrate. Due to the elimination of structural periodicity, the proposed plasmonic color filter works via localized surface plasmon resonances (LSPRs) and thus enables excellent angle-insensitive (up to 60°) performance. In addition, uncoupled LSPRs between nanodisks guarantee stability and reproducibility of the color filter. Finally, a palette of colors across the visible region was obtained with the proposed color filters by simply varying the diameter of nanodisks, exhibiting a promising and robust applicability in digital imaging and sensing industries.

[Simulation Study of Dynamic Color Modulation Based on Tunable Micro/Nano-Structure Array].

With the development of nanotechnology, it has been accessible to display colors by artificial micro/nano-structure, and then the study of structure coloring has become a hot subject, opening a new space for inkless printing. In this paper, a dynamic color modulation method based on tunable micro/nano-structure array is proposed. To tune colors on the same device, a periodic micro/nano-structure array is designed with functional material inside, which could alter the height difference between up and bottom surface precisely by applying an external voltage. It is modeled, and simulated by the Finite Difference Time Domain (FDTD) method in this work. In simulations, perpendicular incident linearly polarized light source is applied, and parameters of surface height difference and period are swept. Series reflective spectra of the devices are obtained, and their corresponding colors are calculated and marked on the CIE 1931 chromaticity diagram. Simulation results demonstrate that when the period is in the range of 100-300 nm, full-color modulation could be realized by varying the height of functional material film via applied voltage, and the peak intensities of reflective spectra are at about 60%, having high energy efficiency. This method is innovative and provides a theoretical basis for the dynamic color modulation micro/nano device, which is quite promising in fields like inkless printing and display technology.

Interferon-stimulated gene 15 as a general marker for acute and chronic neuronal injuries.

Activation of interferon (IFN) signaling in the central nervous system (CNS) is usually associated with inflammation. However, a robust activation of type I IFN-stimulated genes (ISGs) at pre-symptomatic stages occurs in the spinal cord of SOD1(G93A) mice, an amyotrophic lateral sclerosis (ALS) animal model, without obvious signs of inflammation. To determine if the same signaling pathway is elevated in other types of neuronal injuries, we examined the protein expression levels of an IFN-stimulated gene, ISG15, in mouse models of acute and chronic neuronal injuries. We found that ISG15 protein was dramatically increased in the brains of mice subjected to global ischemia and traumatic brain injury, and in transgenic mice overexpressing HIV gp120 protein. These results suggest that activation of ISGs is a shared feature of neuronal injuries and that ISG15 may be a suitable biomarker for detecting neuronal injuries in the CNS.

[Study of the Raman-AFM system for simultaneous measurements of Raman spectrum and micro/nano-structures].

This paper proposes a novel technique of Raman-atomic force microscopy (AFM) combining micro region Raman spectroscopy and AFM imaging. An in-situ probe unit which can simultaneously realize the detection of Raman spectrum and the measurement of AFM image was designed, and a related Raman-AFM system was constructed. Using this system, some experiments were carried out to acquire micro region Raman spectra and AFM images of ZnO nano-particle and TiO2 film. The results show that the Raman spectra of both samples are in agreement with theoretical vaues, and the AFM images represent their micro/nano-structures quite well. These researches prove the feasibility of the Raman-AFM technique which has the potential of being widely applied in the fields of Raman spectroscopy and micro/nano-technology.

Safety and Efficacy of the Metabolic Profiling of the BIMRT Utilizing 18F FDG PET-CT.

AIM: This study aims to evaluate the safety and efficacy of fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) guided intensity-modulated radiation therapy (IMRT) for patients with peritoneal metastases. PATIENTS AND METHODS: A total of 55 patients with peritoneal metastases were treated with 18F-FDG-PET/CT-guided IMRT (BIMRT) from January 2012 to January 2019. They were prescribed with a fraction of the median dose of 2 Gy to a total dose of 50.4 Gy. The multivariate analysis was used the Cox proportional hazard model and the Kaplan-Meier plot was used to perform local control rate (LCR), progression-free survival (PFS), and overall survival (OS) analysis. RESULTS: The 1-year, 2-year, and 3-year LCR were 72.7%, 36.4%, and 9.1%, respectively; the 1-year, 2-year, and 3-year PFS were 69.1%, 30.9%, and 7.3%, respectively, and the median PFS time was 18 months. The 1-year, 3-year and 5-year OS were 70.9%, 28.7%, and 4.2%, respectively. Based on the multivariate analysis using the Cox proportional hazard model, the Karnofsky performance status (KPS) score and radiotherapy joint chemotherapy (RJC) method were independent prognostic-related indicators (P < 0.0001). CONCLUSION: BIMRT may be a safe and effective treatment for patients with peritoneal metastases, especially for patients who cannot undergo surgery. In addition, the results indicated that the patient's KPS score and RJC method were independent prognostic-related indicators for patients survival time.

The Potential Role of PKA/CREB Signaling Pathway Concerned with Gastrodin Administration on Methamphetamine-Induced Conditioned Place Preference Rats and SH-SY5Y Cell Line.

To investigate the effects of gastrodin (GAS) on methamphetamine (MA)-induced conditioned place preference (CPP) in rats and explore its potential mechanisms. MA (10 mg/kg) was initially injected intraperitoneally (i.p.) in rats, after which they were administered either MA or saline alternately from day 4 to 13 (D4-13) for 10 days, followed by treatment with GAS (10 or 20 mg/kg, i.p.) on D15-21 for 7 days. The rats underwent CPP testing after MA and GAS treatment. In vitro, SH-SY5Y cells were exposed to MA (2.0 mM) for 24 h, followed by treatment with GAS (2.0 or 4.0 mM) for 24 h. The expression levels of PKA, P-PKA, CREB, and P-CREB proteins in the prefrontal cortex, nucleus accumbens, and ventral tegmental area of MA-induced CPP rats and in SH-SY5Y cells were detected by Western blot analysis. The MA-induced CPP rat model was successfully established. The administration of MA stimulated a significant alteration in behavior, as measured by the CPP protocol. After treatment with GAS, the amount of time rats spent in the MA-paired chamber was significantly reduced. Results also showed that MA increased the expression levels of PKA, P-PKA, CREB, and p-CREB proteins in the prefrontal cortex, nucleus accumbens, and ventral tegmental area of CPP rats and in SH-SY5Y cells (p < 0.05). GAS attenuated the effect of MA-induced CPP in rats and decreased the expression levels of proteins in vivo and in vitro. Our study suggests that GAS can attenuate the effects of MA-induced CPP in rats by regulating the PKA/CREB signaling pathway.

[Development of photothermal microactuator based on spectral analysis of photothermal expansion material].

The spectral characteristic of materials is the key factor of the photothermal microactuator's performance. The present article introduces the operating principle, and analyzes the relationship between the material spectral characteristic and its expansion. As the photothermal microactuator is an innovative microactuator based on photothermal expansion that absorbs the laser energy and converts it into internal energy to realize the microdrive, the optimal photothermal expansion material with proper absorption spectrum characteristic matching the spectrum of light driving source needs to be found. The reflection and absorption spectra of four types of polymeric material, including PVC, HDPE, LDPE and PET, were obtained by using the single integrating sphere method. The results indicate that the reflection spectrum of the dyed high-density polyethylene (HDPE) is of double-peak structure in visible band, and there is strong absorption within the range of 600-690 nm, which means it would match the light driving source quite well in the broad spectral range. Therefore, HDPE was chosen as the photothermal expansion material. In order to check out the feasibility and performance of the photothermal microactuactor based on HDPE, a prototyping microactuator 1 500 mm in length and 30 mm in thickness was manufactured by using an excimer laser micromachining system. With a laser diode (10 mW/650 nm) as the external power source to activate the microactuator, performance measurement experiments were carried out by using a self-produced video movement measurement system with a CCD-coupled microscope. The experiment results demonstrate that the deflection of the microactuator reaches 18.7 mm at 10 mW of laser power, showing that the characteristics of spectral absorption and light-heat transition are quite well at 650 nm. This novel photothermal microactuator has simple structure, adjustable displacement output, and more mobility, and can be controlled remotely, so it will be quite useful for applications in the fields of micro-optical-electro-mechanical systems (MOEMS).

[Study of in-situ measurement system for porous alumina film based on AFM and reflectometric interference spectroscopy].

An in-situ measurement system for porous alumina (PA) film based on atomic force microscope (AFM) in liquid and reflectometric interference spectroscopy (RIFS) was developed. The present article briefly discusses the principle and structure of the system, and introduces its unique characteristic. The system consists of probe unit, XY scanner, Z-piezo feedback system, computer and software, fiber optic spectrometer, anodization control circuitry etc. When a white light beam illuminates the surface of the film, the reflective light beams at the front and back side of the layer are coherent, and lead to periodical amplifications and extinction in the reflective spectrum with the information of the optical thickness of the film. A fiber optic spectrometer was applied in the system which input the refractive spectrum into the computer by which the optical thickness of the film was calculated. Meanwhile according to the surface topography of PA films by AFM in liquid, the effective refractive index was calculated based on Maxwell-Garnett theory and coherent potential approximation (CPA). So the thickness of PA films could be gained at last. To checkout the feasibility and stability of the system, the real-time scanning and thickness measurement experiments were done during anodization of Al sheets in oxalic acid aqueous solution. In the experiment, the authors used 25 mm diameter aluminum (Al) sheets with 99.999% purity and 0.4 mm thickness as the anode, and graphite rod as the cathode. The pretreatment-cleaned Al sheets were anodized in an aqueous solution of 0.5 mol x L(-1) oxalic acid at the constant temperature (20 +/- 0.2) degrees C with 20 mA x cm(-2) anodization electronic current density. Real-time AFM images of PA film were successfully obtained during anodization. The pore-ratios of Al sheet were 7.81% and 13.83% at oxidizing time 150 min and 180 min respectively. Correspondingly, the effective indexes were calculated to be 1.62 and 1.60, respectively. Combining the reflective spectrum gained by the fiber optic spectrometer, the wave number differences between the two adjacent extrema were 57.69 mm(-1) and 50.00 mm(-1). Based on reflectometric interference spectroscopy, the thickness of PA films was found to be 5.35 and 6.25 microm with oxidizing time 150 min and 180 min respectively. The system has characteristics of convenient manipulation, non-destructive and high-resolution in-situ measurement. And the surface morphology, pore-ratio and effective refractive index can also be gained at the same time.

[Measurement of fruit maturity based on laser-induced photoluminescence spectrum].

Grounding on the concepts of biophotonics measurement, the authors first used a red semiconductor laser (655 nm) to irradiate fruits. Compared with other kinds of illuminating sources, the red semiconductor laser is less expensive and takes little space. The laser-induced photoluminescence spectrums could be detected by coupling fibre-optics probe when the fruits are illuminated by laser. And the spectrum has a distinct peak of relative intensity around the 685 nm wavelength that varies with the degree of fruit maturity. Sugar content measurement was used to prove the laser-induced photoluminescence measurement. The authors tested the sugar content of the fruit specimens, and found that the relative peak value of the fruits' laser-induced photoluminescence spectrum decreases with the increase in their sugar content. The authors used partial least-squares (PLS) regression to perform an analysis of the relationship between the laser-induced photoluminescence intensity and the sugar content, fitting a curve of the two parameters. The correlation coefficient r of the fitted value and the actual value is 98.92% for red-inside plum and 97.31% for nectarine. So the authors could generalize that there is an approximate linear relationship between the peak value of laser-induced photoluminescence intensity and the sugar content of fruits, and we could use the maturity measurement based on this concept to decide the fruit ripeness. The authors designed the analytic program for this laser-induced photoluminescence spectrum measurement system, which mainly realizes two functions: generating the standard ripe spectrum of a certain kind of fruit from a quantity of their spectra, and, according to this standard spectrum, determining the maturity degree of an unknown spectrum, and at the same time, displaying the unknown laser-induced photoluminescence spectrum. Incorporating this analytic program with the optical spectrometer, it becomes conceivable to test the fruit maturity very conveniently and quickly. The measurement system of fruit maturity based on laser-induced photoluminescence spectrum has also been used to test various fruits. This measurement is nondestructive and inexpensive, and does not require complicated equipment, a feature of great importance in real-time measurement of fruit maturity.

Intermediate Temperature Brittleness in Metallic Glasses.

All metallic glasses (MGs), irrespective of their compositions, become brittle in the intermediate temperature range of 0.6-0.7 Tg However, most materials are expected to carry higher strains during deformation with increasing temperature. This behavior of MGs is explained by describing the competition between shear banding and diffusive relaxation processes, and is reminiscent of the "intermediate temperature ductility minimum" observed in polycrystalline metals.

[Study of nanostructures and reflective spectra of porous alumina films].

Several chips of porous alumina films with different nanostructures and scales were prepared by using the method of anodic oxidation. An atomic force microscope (AFM) was employed to image the surfaces of alumina films, and the corresponding reflective spectra of them were acquired with a spectrometer. The experiments show that the alumina films with average pore diameters of 26 and 39 nm feature particular reflective spectra, each consisting of a periodic distribution of peaks and valleys within the wavelength range from 500 nm to 1000 nm. The density or the number of peaks and valleys was determined by the scales of nanostructures. The present paper discussed the relationship between the scale of nanostructures and the distribution of reflective spectra. Some satisfying explanations for them were presented.