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BACKGROUND Since the use of human umbilical cord Wharton's Jelly derived mesenchymal stromal cells (hWJ-MSCs) to treat sarcopenia has not been explored, we studied the effects of hWJ-MSCs in aged male C57BL/6J mice with sarcopenia induced by hindlimb suspension, and explored the potential mechanism. MATERIAL AND METHODS Hindlimb suspension was used to induce sarcopenia in 24-month-old C57BL/6J mice and green fluorescent protein-tagged hWJ-MSCs and controls were transplanted into mice via tail vein or local intramuscular injection. After hWJ-MSC transplantation, changes in whole body muscle strength and endurance, gastrocnemius muscle weight and myofiber cross-sectional area (CSA) were studied. Proliferation of skeletal muscle stem cell, apoptosis, and chronic inflammation were also investigated. RESULTS We demonstrated that whole body muscle strength and endurance, gastrocnemius muscle mass, and CSA were significantly increased in hWJ-MSC-transplanted mice than in controls (P

Fine-tuning pre-trained models have achieved impressive performance on standard natural language processing benchmarks. However, the resultant model generalizability remains poorly understood. We do not know, for example, how excellent performance can lead to the perfection of generalization models. In this study, we analyze a fine-tuned BERT model from different perspectives using relation extraction. We also characterize the differences in generalization techniques according to our proposed improvements. From empirical experimentation, we find that BERT suffers a bottleneck in terms of robustness by way of randomizations, adversarial and counterfactual tests, and biases (i.e., selection and semantic). These findings highlight opportunities for future improvements. Our open-sourced testbed DiagnoseRE is available in https://github.com/zjunlp/DiagnoseRE.

Objectives A targeted surgical approach which accurately determines axillary status after neoadjuvant chemotherapy (NAC) may allow appropriate de-escalation of surgical treatment. It is postulated that the combined use of a particular marker clip, ULTRACOR®TWIRL™ (Bard, Inc.), and specific ultrasound settings for its identification, may overcome the challenges of pre-operative localisation with size diminution of nodes following NAC. Hence, this feasibility study was performed. Methods Three patients with locally advanced breast cancer (LABC), who had the Twirl marker clip placed in biopsy-proven metastatic axillary lymph nodes and completed treatment were included in this preliminary study. Preoperative sonographic identification of the clip and associated node was done on the day of surgery, confirmed by eliciting the ‘twinkle’ artifact, followed by hookwire localisation and resection. The ‘twinkle’ artifact was demonstrated within each specimen after resection. Results All three patients who completed treatment for LABC had successful identification and resection of clipped node aided by the ‘twinkle artifact’. Conclusion The ‘twinkle’ artifact is a novel and useful aid in identifying the Twirl™ clip marking a lymph node in the post-NAC setting, with the potential to be used intraoperatively.

Natural language processing covers a wide variety of tasks with token-level or sentence-level understandings. In this paper, we provide a simple insight that most tasks can be represented in a single universal extraction format. We introduce a prototype model and provide an open-source and extensible toolkit called OpenUE for various extraction tasks. OpenUE allows developers to train custom models to extract information from the text and supports quick model validation for researchers. Besides, OpenUE provides various functional modules to maintain sufficient modularity and extensibility. Except for the toolkit, we also deploy an online demo with restful APIs to support real-time extraction without training and deploying. Additionally, the online system can extract information in various tasks, including relational triple extraction, slot & intent detection, event extraction, and so on. We release the source code, datasets, and pre-trained models to promote future researches in http://github.com/zjunlp/openue.

The InGaN/GaN multi-quantum-wells (MQWs) solar cells employing the surficial GaN nanostructure as light traps were investigated. The performance of the InGaN/GaN MQWs solar cell with nano holes surface shows an obvious advantage over that with nano poles, much less than the planar one. From the measurements of EQE and photoluminescence spectra, the enhancement of photoelectric response contributes to the device performances. Because the effective light absorption is increased, the conversion efficiency significantly improves from 1.02% (planar surface) up to 2.235% (nano holes surface). Although the performance is still low, it is exactly an effective method to enhance the conversion efficiency via introducing nanostructures on the surface of the InGaN/GaN MQWs cells.

In this work, we report a method that the Si substrate is pre-treated in the atmosphere of high temperature AlN before the depositon of Al to improve the quality of GaN-on-Si, which is studied by few people. Compared to the untreated sample, the pre-treated one exhibits smoother surface morphology with a root mean square roughness (RMS) value of 0.580 nm and the full width at half maximum (FWHM) of GaN (102) plane also decreases from 1484 arcsec to 1303 arcsec. Moreover, we give an explanation for the extra shoulder peaks in the photoluminescence (PL) spectrum. This enhancement of quality and surface morphology of GaN can be attributed to the improvement of surface flatness of Si substrate, which contributes to the conversion of AlN to two-dimensional growth mode, leading to a smoother surface of GaN. And the reason for the improvement of Si substrate is also investigated in this work.

An InGaN/GaN solar cell including a dual multiple quantum wells (MQWs) structure is investigated. It shows an obvious advantage over the conventional InGaN/GaN cell, which only contains a single MQWs structure. Because the short current density ( ${J} _{\mathrm { {sc}}})$ increases, the 1 sun power conversion efficiency significantly improves from 0.62% (single MQWs cell) to 1.02% (dual MQWs cell). From the measurement of EQE and PL spectra, the enhancement of effective photoelectric response within the solar spectrum mainly contributes to the high device performance, due to the introduced upper MQWs of higher In content.

A nanomembrane with optical nanocavity structure was investigated employing finite difference time domain method in this paper. The nanomembrane with a typical thickness less than a few hundred nanometers can promote optical absorption sharply by introducing nanocavity structure. Geometrical parameters of the structure have a profound impact on the optical absorption of nanomembrane, which was studied in this paper. It was found that the nanocavity structure can enhance the absorption of visible light with different wavelengths by adjusting the thickness of different layers.

AlGaN/AlN/GaN heterojunctions were irradiated by 3 MeV protons with different fluences. Hall and C-V measurements showed that the density and mobility of 2DEG for heterojunctions decreased after proton irradiation. The crystal quality and optical properties of AlGaN/GaN heterojunctions were characterized by the variations of the micro-Raman scattering spectra, XRD and photo luminescence (PL) spectra with proton fluence. It has been obtained that the strain and dislocation of GaN and AlGaN were not affected by the proton injected. The proton irradiation caused the increase of structural defects in HT-AlN buffer layer, which lead to the red shift of ${{\rm A}_1}$ (LO) mode. The higher tails of XRD rocking curve indicated the introduction of point defects by irradiation. The full-width at half-maximum (FWHM) of ${\rm E}_2^{\rm high}$ phonon mode broadened, which was consistent with change of FWHM of PL near-band-edge emission (BE). The spectra of yellow band normalized to the intensity of BE demonstrated a great increase of Ga vacancies related defects, which may be the main reason for the degradation of optical properties.

The concept of multi-constrained analysis of the cutting process is presented for the first time in the paper. The paper adopts a method to solve an important problem which is how to judge the influence of constrains during the cutting process. The research results are applied for HSS drills for cutting stainless steel. On the basis of the multi-constrained analysis combined with methods of simulations and standard experiments, the optimum methods are provided for structure, coating and cutting parameters of cutting tools. For geometric structure of tools, optimization is to increase thickness of cutting and rake angle. Coating optimization strategy is choosing high temperature hardness and low thermal conductivity coating. Optimization of cutting parameter is to adjust feed fate, then select proper cutting speed. The conclusion of paper is helpful for the cutting optimization.

Due to a variety of electrical equipment using, the grid power quality severely polluted. For current harmonic signal is generated in hoist converter, the methods is proposed based on Hilbert-Huang Transform (HHT) to detect current harmonic signal and improved Active Power Filter (APF). The simulation mode is established by MATLAB/Simulink software about shunt APF+SPWM inverter hybrid active filter device for harmonic motion detection and suppression simulation. The results show that the harmonic of hoist converter can be detected by this design method real-time and the harmonic can also be suppressed validly.

Gas monitoring is considered as the most important mean in the safe production of coalmine. Time delay inevitably exists in the current gas monitoring technology widely used today. This research uses Support vector machine to forecast gas concentration. ZigBee wireless network protocol is adopted so that a wireless gas monitoring network with concentration predicting function is obtained. In this way the present time delay in Gas concentration monitoring will be improved and the scope of monitoring will be expanded at the same time

A supervisory control and data acquisition system is designed for wind farms, including the local controller and remote monitoring terminal. The data of the sensors collected by the lower-computer is transmitted to the host computer monitor terminal through the GPRS wireless network after preliminary treatment. In the host computer, the data is processed and displayed by the virtual instrument. The remote monitoring terminal can also send commands to control the actuators in the wind farm. Wavelet de-noising principle is used to process the data collected, improving the reliability and stability of the system.

Along with the tension of global energy and the improvement of environmental awareness, more and more Research institute begin examining how to change low-concentration gas into treasure. So we design the intelligent controller with ARM920T as its main control chip, set up an intelligent controller with two inputs, which will dilute the concentration from 4%-8% to 3.8% and the transmission can be carried out under constant pressure. We have made simulation toward the system by using Simulink in MATLAB and Fuzzy toolbox. The results show that the control effect turns out to be fine and has reached the performance indicators of power supply control system of low-concentration gas. This program will be proved to be an ideal intelligent control plan.

To reduce the frequent occurrence accidents of mining areas, a set of monitoring system of monitoring the operational status of mining equipment is designed. The information of electromechanical equipment are collected by the on-off sensors with anti-interference, which are converted to the standard RS485 interface signal though the MCU（Microprogrammed Control Unit）, and transmission to the monitoring platform by the bus transfer. The monitoring system is convenient and saves the cable, which can monitor the operational status of the field devices with accurate and real-time.

The effect of 3-MeV proton irradiation on InGaN/GaN multiple quantum wells (MQWs) solar cells was investigated. The irradiation degradation of the photoluminescence characteristics of the InGaN film was also measured, indicating its potential to be used in space solar cells. With the proton fluence increasing from 0 to 1 × 10 14 /cm 2 , the conversion efficiency (η) of the InGaN/GaN MQWs cell declined from 0.61% to 0.14%.

Nitrogen-doped ZnO (ZnO:N) thin films with multi-buffer-layers, Mg0.1Zn0.9O / ZnO super-lattice structure, were grown on sapphire (0 0 0 1) by plasma-activated laser molecular beam epitaxy (L-MBE) using an atomic nitrogen source. High resolution X-ray diffraction (HR-XRD) measurement demonstrated that all the ZnO:N samples are (0 0 0 2) oriented and the residual strain along c-axial are effectively controlled. Room temperature (RT) Hall measurements indicate that the 200 °C sample shows a p-type behavior with a mobility of 4.08 cm2/V s and a carrier density of 1.47 × 1 0 17 cm−3. The 300 °C sample shows a weak p-type behavior with a mobility of 0.75 cm2/V s and a carrier density of 4.40 × 1 0 16 cm−3. However, the 200 °C sample is not stable and reverted back to n-type conductivity in about 5 days. The X-ray photoelectron spectra (XPS) of N1s display two peaks at 404 eV and 396 eV which are related to (N2)Oand NO, respectively. The 10 K low temperature photoluminescence (PL) spectra of the 200 °C sample exhibits an acceptor bound exciton peak at 3.351 eV and a donor–acceptor pair (DAP) peak at 3.228 eV, associated with NO acting as acceptors.

A back-illuminated vertical-structure ZnO ultraviolet (UV) detector was fabricated using an indium-tin oxide (ITO) electrode. Ordered ITO and ZnO films were grown on a quartz substrate by radiofrequency sputtering. At 5 V bias, the dark current was 640 μA and the photocurrent was 16.8 mA under UV illumination (365 nm, 10 μW), indicating a high responsivity of 1616 A/W. The response time measurements showed a rise time of 71.2 ns and a decay time of 377 μs. The ZnO detector performed well and can be used in a focal-plane array for UV image detection.

A high-performance metal-semiconductor-metal (MSM) ultraviolet photodetector was fabricated based on a ZnO film with Al interdigitated (IDT) electrodes. A c-axis-oriented ZnO film was grown on a SiO2/Si (100) substrate at room temperature by a reactive radiofrequency (RF) sputtering technique and then annealed at 900°C in pure O2 ambient for 1 h. The fabricated ZnO ultraviolet (UV) detector demonstrated a high responsivity of 2069 A/W when biased at 5 V, which could be attributed to the influence of the annealing process in pure O2 ambient. The response time measurement showed a rise time (10–90%) of 45.1 ns and a decay time (1 − 1/e) of 541 μs.

Flexible fixturing is a necessary aspect of flexible manufacturing systems (FMS) and computer-integrated manufacturing systems (CIMS). Modular fixtures are mostly used in industry for job and small batch production. Computer-aided fixture design (CAFD) has become a research focus in implementing FMS and CIMS. Fixture configuration design is an important issue in the domain of CAFD. A review of the current research in CAFD indicates that one major problem impeding the automated generation of fixture configuration design is the negligence of study on fixture structures. This paper investigates fundamental structures of dowel-pin based modular fixtures and fixturing characteristics of commonly used modular fixture elements. A modular fixture element assembly relationship graph (MFEARG) is designed to represent combination relationships between fixture elements. Based on MFEARG, algorithms are developed to search all suitable fixturing unit candidates and mount them into appropriate positions on the baseplate with an interference check. A prototype system for automated design of dowel-pin modular fixture configurations is presented in this paper. Fixture design examples are given at the end of the paper.

This paper presents a set of feature parameters characterizing tool wear and fracture in turning and endmilling processes which are extracted from the acoustic emission (AE) and vibration signals through frequency analysis and multistep extraction analysis. A tool wear and fracture fusion model is made on the relevance analysis trend analysis and the least square regression. Based on the recognition algorithm of selfsimilar analysis the value of tool wear can be calibrated. Using the abovementioned research results a realtime tool monitoring system is developed for turning and endmilling processes with higher rate of success fewer prediction errors and faster response time

ZnO thin films were grown on SiO 2 /Si substrates by radio-frequency magnetron sputtering. Based on the ZnO film, a photoconductive metal-semiconductor-metal ultraviolet detector was fabricated by a liftoff technique. Its I-V characteristics were observed at 365 nm, and a fast response was observed by illumination with a KrF excimer laser.