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Bencheng Sun,1–3,* Xiao Wang,1–2,4,* Yi Pan,1–2,4 Ya Jiao,1,2 Yongjun Qi,1–2,4 Hongmin Gong,1–2,4 Duyin Jiang1–2,41Department of Emergency, The Second Hospital of Shandong University, Jinan, Shandong Province, People’s Republic of China; 2Department of Emergency and Department of Burns and Plastic Surgery, The Second Hospital of Shandong University, Jinan, Shandong Province, People’s Republic of China; 3Department of Burn and Plastic Surgery, Linyi People’s Hospital, Linyi, Shandong Province, People’s Republic of China; 4School of Medicine, Shandong University, Jinan, Shandong Province, People’s Republic of China*These authors contributed equally to this workBackground: Malignant melanoma is the most lethal form of cutaneous tumor and has a high metastatic rate and motility capacity. Owing to the poor prognosis, it is urgent to seek an effective therapeutic regimen. Human mesenchymal stem cells (MSCs) can home to tumor cells and have been shown to play important roles in both promoting and inhibiting tumor development. Fetal dermal MSCs (FDMSCs), derived from fetal skin are a novel source of MSCs. Nevertheless, the antitumor capacity of FDMSCs on malignant melanoma is not clearly understood.Materials and methods: FDMSCs were extracted from the dorsal skin of fetal tissues. A375 melanoma cells lines were obtained from American Type Culture Collection. The effects of conditioned media from FDMSCs (CM-FDMSC) on A375 melanoma cells were tested in vivo using tumor formation assay and in vitro using cell viability, 5-ethynyl-2ʹ-deoxyuridine incorporation, flow cytometry, TdT-mediated dUTP Nick-End Labeling (TUNEL), wound healing, transwell invasion, and Western blotting.Results: CM-FDMSC inhibited A375 tumor formation in vivo. In vitro, CM-FDMSC inhibited the tumor-related activities of A375 melanoma cells, as evidenced reductions in viability, migration, and invasion. CM-FDMSC-treated A375 cells showed decreased phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), and extracellular signal-regulated kinase (ERK) phosphorylation, and up-regulation of Bcl-2-Associated X (BAX) and down-regulation of B-cell lymphoma-2 (BCL-2) expression.Conclusion: CM-FDMSC can inhibit the tumor-forming behaviors of A375 melanoma cells and inhibit PI3K/AKT and mitogen-activated protein kinase signaling to shift their BCL-2/BAX ratio toward a proapoptotic state. Identification of the bioactive components in CM-FDMSC will be important for translating these findings into novel therapies for malignant melanoma.Keywords: human fetal dermal mesenchymal stem cells, melanoma, conditioned media, apoptosis, PI3K/AKT signaling pathway, MAPK signaling pathway

China’s LAMOST telescope is the most powerful spectroscopic measurement telescope for studying large field of view and large sample astronomy. It combines the world’s leading splicing mirror technology with thin mirror technology for the first time, breaking through the inability of previous astronomical instruments to combine large clear apertures and wide The bottleneck of the field of view. In order to more accurately detect the movement between the sub-mirrors of large-aperture telescopes, it is necessary to install a precise sensor at the edge of the sub-mirror to detect the movement between the sub-mirrors, and then adjust the mirror displacement in time through the force actuator under the mirror to obtain more Good image quality. Due to the particularity of the mirror surface, there are strict requirements on the displacement measurement accuracy of the sensor. Its research focuses on the acquisition and filtering of sensor displacement signals. In order to extract useful digital signals from strong noises and improve the signal-to-noise ratio (SNR) of the digital signals output by the detection system, this paper proposes a dual-channel digital filtering algorithm combining improved four-entry wavelet and adaptive filtering. By improving the four-entry wavelet algorithm, the algorithm improves the reconstruction capability and linearity while taking into account the multi-resolution characteristics of the traditional wavelet transform algorithm, and ensures the continuity of the wavelet coefficients at the threshold; and the second channel collects the high The frequency characteristic noise signal is processed again through adaptive filtering, and finally a sensor displacement signal with a higher signal-to-noise ratio (SNR) is obtained. After the front-end algorithm development is completed, the displacement signal acquisition and processing system is realized through the ZYNQ-7000 development platform, including AD conversion, digital filtering, signal transmission and LCD screen display, etc., and the Gui interface program is written using Matlab to convert the displacement signal Real-time display and save records on the PC side. The entire experiment of the displacement sensor was carried out at the Nanjing Institute of Astronomical Optics Technology, Chinese Academy of Sciences. The results show that the digital signal-to-noise ratio (SNR) processed by the algorithm is 20.7% higher than that of the traditional wavelet algorithm. The root mean square error (RMSE) of the fitted displacement curve is reduced by 19.8% on average, and the running time was reduced by 50%. It shows that the algorithm is accurate and fast, and its entire signal processing system has important application significance for the research of displacement sensors between splicing mirrors of large astronomical telescopes.

Objective. To compare the efficacy and safety of combination of Aidi injection and chemotherapy and chemotherapy alone in treatment of breast cancer. Methods. The related control and randomized studies till August 1st, 2020, were retrieved in the database including PubMed, Embase, Cochrane Library, CNKI, CBM, Wang-Fang, and VIP. Primary outcomes were response rate (RR) and performance status (KPS) improvement rate; secondary outcomes were rate of adverse drug reactions (ADR) including myelosuppression, digestive tract reaction, liver dysfunction, and cardiac toxicity. Review Manager 5.3 was used in the present analysis. Results. In total, 20 studies (18 articles) were included in the present analysis. RR (OR 1.76 (1.32, 2.35); p=0.0001) and KPS improvement rate (OR: 2.68 (1.34, 6.46); p=0.007) in Aidi injection plus chemotherapy group were significantly higher than those of chemotherapy alone group. Addition of Aidi injection significantly reduced the rate of myelosuppression, digestive tract reaction, leukocyte decrease, II-IV cardiac function abnormality, atrial dysrhythmia, ventricular arrhythmia, ST segment T wave inversion, and abnormal ECG (all p

Checking of the micro-displacement between the segmented mirrors of the large aperture telescope is the foundation of the Active Optical System to adjust the system to gain the optimum observing effect. In this paper, the signal processing system of a new type of area-alterable differential capacitive micro-displacement sensor used in the active optical system was designed, including both the hardware and software of it. The hardware consists of the high performance instrument amplifier, the lock-in demodulator, Analog to Digital converter, FPGA and the microprocessor. The software includes the MCU codes and FPGA-based modules such as the excitation pulse generation, system control and implementation of the signal processing algorithms. On the basis of the EDA simulation and test of the circuit modules, the schematic and PCB layout were designed and the experimental setup was assembled. Then the codes of FPGA and Microprocessor were designed and debugged. In the end, the system was tested on the platform of the micro-displacement experiment. Results showed that the general design scheme is feasible although the precision of the system is needed to be improved.

In the Active Optical System, the precise measurement of the micro-displacement is the important evidence for the adjustment of the segmented mirrors and has great influence upon the full playing of the system’s optical performance. In this paper, both the median and adaptive filters are designed and simulated based on MatLab platform to remove the noises in the received signal of the micro-displacement sensor which has the features of low frequency, small amplitude and being susceptible to interference. The algorithms are also verified in the real micro-displacement measuring system. The results show that both of these two algorithms are effective and contribute to improve the system’s performance.

The relationship between capital structure and product market competition is a field got much concern from economic scholars recently, but research works got so far seem to neglect their bidirectional relationship. Considering this deficiency, I take Chinese A-stock listed companies as research objects, and use a systemic equation model to test the bidirectional relationship between companies' capital structure and their product market competition intensity. The test results indicate that both debt ratio and product market competition intensity have statistically significant negative effects on each other.

Traditional financial theories considered firms' financing strategy only from the perspective of debts' tax shield benefits and their financial distress costs, and overlooked the effects of high debt ratios on firms' sustainable development. High debt ratios not only affects firms' investing behavior and market competition behavior, but also affects the trading behavior of their stakeholders such as customers, suppliers, employees, creditors and shareholders. These could further affect firms' future development and survival. Based on the above considerations, firms should reduce their debt ratios accordingly to achieve more sustainable development when making their financing strategy.