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Objective: To investigate 38 Y-chromosome short tandem repeat (Y-STR) genetic polymorphisms in Beijing Han and analyze the genetic distance with neighboring or linguistically similar populations. Materials and Methods: In the study, we selected 531 unrelated male individuals of Beijing Han, and the results were statistically analyzed by testing with GSTAR™ 41Y reagents. Results: The allele peak heights were balanced among the Y loci, the amplified fragment ranged from 100 to 500 bps. A total of 531 haplotypes were detected in 531 samples. Eight null genotypes were observed on locus DYS448. One and three double alleles were observed on single-copy locus DYS576 and DYS19, respectively. DYS385 a/b, DYF387S1 a/b, and DYS527 a/b were more common in double copies, but 3, 13, and 11 triple alleles were detected, respectively. The gene diversity values of Y-STRs except DYS391, DYS438, and DYS645 were >0.5. Twenty-seven Y-STRs of Beijing Han population were selected for genetic distance comparison with 17 populations including Changchun Han, with Rst values ranging from 0.0002 to 0.1703. Conclusion: The 38 Y-STRs in this study have strong male lineage identification ability and have great potential for individual identification, kinship identification, Y-STR database construction, and genetic relationship research. [ABSTRACT FROM AUTHOR]

We present an electrically tunable superconducting metamaterial capable of modulating terahertz (THz) waves. The device consists of two concentric ring resonators, which exhibits the electromagnetically induced transparency-like spectral response. A relatively high modulation depth of 86.8% and a group delay of 25.4 ps were achieved at the transmission window. The experimental and simulated transmission spectra show good agreement. The hybrid coupling model could well explain the physical mechanism. The tuning of group delay of THz waves is of great significance to the applications of THz technology. [ABSTRACT FROM AUTHOR]

Uncooled Nb5N6 array detector has been designed and fabricated for 0.65 terahertz (THz) detection. The length and width of the optimized bow tie antenna in the periodic structure of 150 × 150 μm2 are 130 and 50 μm by using CST MICROWAVE STUDIO. The electric field intensity at the center point of the bow tie antenna is about 550‐factor enhancement at 0.647 THz. Furthermore, the periodic structure of the substrate is continuously optimized when the dimensions of the bow tie antenna are kept constant. It is found that the electric field intensity increases with the increase of periodic sizes. Compared with the periodic size of 150 × 150 μm2, the optimized periodic size is 200 × 230 μm2 and the electric field intensity is increased by three times. The experimental results show that the measured optical voltage responsivity of the Nb5N6 array detector with the periodic structure of 200 × 230 μm2 is about three times than that of the Nb5N6 array detector with the periodic structure of 150 × 150 μm2, which is basically consistent with the simulation results. [ABSTRACT FROM AUTHOR]

Abstract: Ni0.5Zn0.5Fe2O4 nanoparticles were synthesized by the facile citrate–gel process and the preliminary measurement for adsorption of bovine serum albumin (BSA) protein on these nanoparticles was carried out. The gel precursor and resultant nanoparticles were characterized by TG-DSC, FTIR, XRD, TEM and VSM techniques and the BSA adsorption on the nanoparticles was analyzed by UV spectrophotometer at room temperature. The results show that the single phase of spinel Ni0.5Zn0.5Fe2O4 is formed at 400°C. With increasing calcination temperature from 400 to 700°C, the average grain size increases from about 14 to 45nm and consequently, the specific saturation magnetization of Ni0.5Zn0.5Fe2O4 nanoparticles increases from about 46 to 68Am2/kg. The coercivity initially increases and then decreases with increasing calcination temperature, with a maximum value 9.2kA/m at 500°C. The as-prepared Ni0.5Zn0.5Fe2O4 nanoparticles exhibit a good adsorbing ability for BSA and the optimized adsorption is achieved for the Ni0.5Zn0.5Fe2O4 nanoparticles calcined at 500°C with grain size about 24nm. [Copyright &y& Elsevier]

Abstract: The magnetic nanocomposites of (1− x)Ni0.5Zn0.5Fe2O4/xSiO2 (x =0–0.2) were synthesized by the citrate-gel process and their absorption behavior of bovine serum albumin (BSA) was investigated by UV spectroscopy at room temperature. The gel precursor and resultant nanocomposites were characterized by FTIR, XRD, TEM and BET techniques. The results show that the single ferrite phase of Ni0.5Zn0.5Fe2O4 is formed at 400°C, with high saturation magnetization and small coercivity. A porous, amorphous silica layer is located at the ferrite nanograin boundaries, with the silica content increasing from 0 to 0.20, the average grain size of Ni0.5Zn0.5Fe2O4 calcined at 400°C reduced from about 18–8nm. Consequently, the specific surface area of the nanocomposites ascends clearly with the increase of silica content, which is largely contributed by the increase in the thickness of the porous silica layer. The Ni0.5Zn0.5Fe2O4/SiO2 nanocomposites demonstrate a better adsorption capability than the bare Ni0.5Zn0.5Fe2O4 nanoparticles for BSA. With the increase of the silica content from 0 to 0.05 and the specific surface area from about 49–57m2/g, the BSA adsorption capability of the Ni0.5Zn0.5Fe2O4/SiO2 nanocomposites calcined at 400°C improve dramatically from 22 to 49mg/g. However, with a further increase of the silica content from 0.05 to 0.2, the specific surface area increase from about 57–120m2/g, the BSA adsorption for the nanocomposites remains around 49mg/g, owing to the pores in the porous silica layer which are too small to let the BSA protein molecules in. [Copyright &y& Elsevier]

In this Letter, we propose and demonstrate a new type of planar double-slot antenna for a N b 5 N 6 microbolometer terahertz (THz) detector. The calculated results show that the planar antenna possessed high coupling efficiency, and the THz signals were obviously focused on the antenna center place. The new planar antenna was integrated with N b 5 N 6 microbolometer THz detectors using micro-fabrication technology. The measured results showed that the maximum optical voltage responsivity ( R o ) of the detectors reached up to 113 V/W at 0.643 THz, and the corresponding noise equivalent power was 44pW/√Hz. In addition, the performance of double-slot antennas applied into array detectors in a tunable Fabry-Perot cavity was investigated. The measured results of the N b 5 N 6 THz detector remained almost unchanged when the distance between the chip substrate and the copper plate was altered. This indicated that this planar double-slot antenna, which possessed the advantages of high coupling efficiency and easy integration, has great application prospects in a THz detector.

Cell-penetrating peptides (CPPs) have been considered as a powerful tool to improve the intracellular and nuclear delivery efficiency of nanocarriers. However, their clinical application is limited because of their nonspecific targeting function, short half-life, and severe system toxicity. Herein, we have developed a polymeric nanocarrier with a tumor acidity-activatable arginine-rich (R9) peptide for targeted drug delivery. The nanocarrier is fabricated with a R9-conjugated amphiphilic diblock polymer of poly(ethylene glycol) (PEG) and poly(hexyl ethylene phosphate) (PHEP), and then further coated with tumor acidity-activatable polyanionic polyphosphoester through electrostatic interaction in order to block the nonspecific targeting function of the R9 peptide. In the slightly acidic tumor extracellular environment (∼pH 6.5), tumor acidity-activatable polyanionic polyphosphoester would be deshielded from the nanoparticles, resulting in the re-exposure of the R9 peptide to enhance tumor cellular uptake. As a result, intracellular concentration of payload in 4T1 tumor cells significantly increased at pH 6.5. And, we further demonstrate that such a delivery system remarkably promoted the anti-tumor efficiency of chemotherapeutic drugs in tumor-bearing mice, offering great potential for drug delivery and cancer therapy.

Room-temperature thermal detection at a wavelength of 2 µm in the short-wave infrared range (1.7-3 µm) was demonstrated for the first time using a Nb 5 N 6 microbolometer. The photothermal responses of two types of Nb 5 N 6 microbolometers were evaluated. By suspending Nb 5 N 6 microwires in the air above the substrate, a reduction in thermal conductance of the device by a factor of 39 was achieved. The measured optical voltage responsivity R O of the Nb 5 N 6 microbolometer reached the value of 61.5 V/W. A noise equivalent power of 8.5 × 10 -11 W/√Hz (at 1 kHz) and a detectivity D* = 2.0 × 10 7 cm√Hz /W with a typical response time as small as 0.17 ms was obtained at a wavelength of 2 µm for a 10 × 30-µm 2 device. The performance could be improved further by optimizing the design and operating parameters. This study revealed a simple low-cost technique to develop a large-scale focal plane array in silicon for infrared detection.

Fabricating resonant cavities with conventional methods to improve the coupling efficiency of a detector in the terahertz (THz) region is difficult for the wavelength is too long. Here, we propose a solution by using the substrate cavity effect given that the substrate wavelength and thickness of the preparation device are in the same order. The planar dipole antenna-coupled Nb 5 N 6 microbolometers with different substrate thicknesses were fabricated. The interference effect of the substrate cavity on the optical voltage response of the detector is analyzed experimentally and theoretically. The experimental results show that the optical response of the detector is determined by the length of the substrate cavity. Thus, the THz devices with different detection frequencies can be designed by changing the substrate cavity length. Furthermore, on the basis of this substrate cavity effect, an asymmetric coupled Fabry-Pérot (FP) cavity is constituted by simply placing a movable metallic planar mirror at the backside of the Si substrate. The incident THz radiation on the Nb 5 N 6 microbolometer can be effectively manipulated by changing the substrate-mirror distance to modulate the phase relation between the reflect wave and the incident wave. The distinct radiation control can be observed, and the experiments can be well explained by numerically analyzing the responsivity dynamics that highlights the role of the FP cavity effect during radiation. All of the results discussed here can be extended to a broad range of frequency and other type of THz detectors.