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Based on the random distribution characteristic of abrasive grains for the grinding wheel circumference surface during the manufacturing process, considering the grinding parameters and deflection parameters comprehensively, a randomly deflected truncated cone shape single abrasive grain cutting simulation model was established. Then, studying its cutting mechanism: the trajectory length value by numerical method and formula method were compared, the consequence indicates that the error is extremely small, this demonstrates the accuracy of the numerical method. The calculation and analysis of the workpiece cutting surface topography and the undeformed chip shape were carried out, it shows that the cutting surface topography and the undeformed chip shape are coincident. The influence laws of each grinding process parameter on the material removal volume (MRV) and material removal rate (MRR) were investigated, the results display that the grinding method affects the changing pattern of MRV and MRR, when the grinding method was up-grinding, a high wheel speed or a small wheel diameter are able to enhance the MRR, the MRV and MRR are increments with the increasing workpiece feed speed or abrasive grain cutting depth, and the MRV and MRR decrease with the raising of the absolute value of single abrasive grain deflection angle. The situation is a similar or opposite trend in down grinding. This work can provide a theoretical reference for the selection and optimization of grinding parameters, and further lay a foundation for the research in the grinding mechanism of the grinding wheel.

Nanoscale wear can severely limit the performance of tips used in atomic force microscopy, especially in contact and lateral mode operations. Hence, we investigated the mechanical and tribological properties of a newly invented nano-spherical silicon tip produced

This study investigates the relationship between the mRNA expression of nuclear factor erythroid 2-related factor 2 (NRF2) and Tumor protein p53 (TP53) in circulating tumor cells (CTC) and sensitivity to radiotherapy in patients with esophageal cancer. To investigate the relationship between cytokines IL-6, CD8Radiosensitivity was assessed by measuring a morphological or functional change in the tumor in response to ionizing radiation. Fasting venous anticoagulated blood (EDTA anticoagulation) was drawn from patients, and the Trizol-chloroform two-step method was used for RNA extraction. Data were collected from 45 patients admitted with radiotherapy alone from January 2018 to December 2021. The expression levels of NRF2mRNA (Messenger Ribose Nucleic Acid) and TP53mRNA in CTCs were detected by reverse transcription-polymerase chain reaction (RT-PCR). Pre- and post-treatment changes in IL-6 and CD8Twenty-six cases were sensitive to radiotherapy, and 19 were resistant, for a radiotherapy sensitivity rate of 58.8%. NRF2mRNA and TP53mRNA values increased in 19 radiotherapy-resistant patients and decreased in 26 radiotherapy-sensitive patients compared with those before radiotherapy (P = 0.001, P＜0.05). The ΔCT values of NRF2mRNA and TP53mRNA before treatment were moderately correlated with prognosis (P 0.002). Inflammatory cytokine IL-6 was elevated in 22 of 45 patients after radiation, P = 0.04. NRF2 mRNA level was consistently elevated with CD8The expression of NRF2mRNA and TP53mRNA in the CTCs found in the peripheral blood of patients with esophageal squamous carcinoma was significantly associated with the sensitivity to radiotherapy. NRF2 mRNA level was consistently elevated with CD8

Allium hookeri is a rare medicinal plant with unique flavor. In this study, the first complete chloroplast (cp) genome of A. hookeri was sequenced and assembled based on the next generation sequencing. The cp genome is 153,592 bp in length, including a large single-copy (LSC) region of 82,609 bp, a small single-copy (SSC) region of 17,487 bp, and a pair of inverted repeat (IR) regions of 26,748 bp each. The genome encodes 131 genes, including 86 protein-coding genes, 39 tRNA genes, and six rRNA genes. The GC content of whole genome is 36.99%. The phylogenetic analysis based on 24 complete cp sequences revealed that A. hookeri was at the base of the phylogenetic tree, indicating an older species in the Allium genus.

Purpose The problem of port and starboard ambiguity will exist when only utilize the vector or scalar parameters. Meanwhile, the amplitude-phase error between the vector and scalar can also cause this problem. In this paper, a compound MEMS vector hydrophone which contains cilia vector microstructure and piezoelectric ceramic tube has been presented to solve the problem. Compared with traditional MEMS vector hydrophone, the compound MEMS vector hydrophone can realize the measurement of sound pressure and vibration velocity simultaneously. Design/methodology/approach A compound MEMS vector hydrophone has been presented. The unipolar directivity of the combined signal which combine the acoustic pressure and vibration velocity is used to achieve the direction of arrival (DOA). This paper introduced the working principle and the target detection mechanism of the compound vector hydrophone. The amplitude and phase error are analyzed and corrected in the standing wave tube. After that, the authors use beam-forming algorithm to estimate the DOA. Findings The experimental results in the standing wave tube and the external field verified the vector hydrophone's directional accuracy up to 1 and 5 degrees, respectively. Practical implications The research of compound vector hydrophone plays an important role in marine acoustic exploration and engineering applications. Originality/value This research provides a basis for MEMS hydrophone directivity theory. The compound vector hydrophone has been applied in the underwater location, with a huge market potential in underwater detection systems.

The previous cilia MEMS vector hydrophone were mainly aimed at monitoring the noises of remote ships due to the limitation of frequency band. Moreover, the methods of adding appendants to cilia were usually used to improve the sensitivity, which increased the difficulty of fabrication, secondary integration and the consistency of production. In this paper, based on the bionic principle of multiple cilia on fishes’ sense cells, a cilia cluster MEMS vector hydrophone(CCVH) is designed. This micro-structure not only improves the sensitivity of hydrophone without adding appendants to cilia, but also designs a suitable frequency band to monitor ships and some valuable marine species. Firstly, a mathematical model is established for theoretical analysis. Then, simulation analysis is carried out to verify the correctness of theoretical analysis, and the optimal size of cilia is found simultaneously. Secondly, the fabrication of cilia cluster MEMS vector hydrophone is more simpler because the cilia have the same properties and integrated process. Finally, test results show that the sensitivity of hydrophone has been increased by 9.6 dB, which can reach up to -183.3 dB@1600 Hz(0 dB ref.1 V/uPa) with the frequency band in the range of 20 Hz-1 kHz. Besides, the sensitivity is increased by 6 dB per octave. Concave point depth of 8-shaped directivity is beyond 30 dB, which indicates that CCVH is promising in underwater application.

The rotary table is the key component in the optimal design of roadheaders. In this study, a simulation model of the cutting part and a rotary table is established in SolidWorks, and stress analysis and strength evaluation of the structure of the rotary table are performed. To this end, finite element analysis is performed on the basis of the dynamic theory of a coupled multibody system comprising rigid and flexible bodies. Considering actual working conditions, the load file of the cutting head is calculated based on the development of the “Roadheader Machine load Calculation Program”, and the stress and strain cloud map of the cutting head running to the bottom left, middle end, and right end of the rotary table is obtained through Adams simulation. Then, the 6-order modal analysis is carried out, and the S-N curve of the turntable is finally established. In addition, the fatigue life reliability of the turntable is analyzed using the AWE fatigue module. The results show that, provided reliable working conditions, the EBZ160 type roadheader machine during the normal service life shows no risk of fatigue failure under normal working load.

In view of low sensitivity of traditional stethoscope and valuableness of existing intelligent electronic stethoscope, a T-type MEMS heart sound sensor with high sensitivity, low cost and high SNR is designed, which is combined with MEMS technology, bionic principle, piezoresistive principle and Wheatstone bridge detection principle. Firstly, working principle of T-type MEMS heart sound sensor is introduced; Secondly, theoretical model of T-type sensitive microstructure is established, and its performance is simulated and analyzed by ANSYS finite element simulation software, then the size of T-type sensitive microstructure is determined and T-type MEMS heart sound sensor is made. Finally, T-type MEMS heart sound sensor prototype is tested. The results of tests show that: sensitivity and working frequency band of T-type MEMS heart sound sensor are respectively -183dB@500 Hz and 0–1000 Hz, which have verified correctness and practicability of T-type microstructure. In addition, the acoustic properties of S1 and S2 are analyzed from time domain and frequency domain, which indicates that heart sound signals detected by T-type MEMS heart sound sensor are highly consistent with that of 3200-type electronic stethoscope of 3 M company. Moreover, SNR of T-type MEMS heart sound sensor is 7.9 dB higher than 3200-type electronic stethoscope of 3 M company. The above shows that the T-type MEMS heart sound sensor can provide a powerful basis for early accurate diagnosis of cardiovascular disease and has broad prospects in the field of heart sound detection.

Three-dimensional vector hydrophone plays an important role in underwater spatial location. In order to solve the problems of monolithic integration and linearity of previous three-dimensional vector hydrophones, a three-dimensional micro-electro-mechanical system (MEMS) vector hydrophone based on the piezoresistive effect and bio-inspired principle is proposed in this paper. Different from previous three-dimensional vector hydrophone, this three-dimensional MEMS vector hydrophone is monolithically integrated. It has the characteristics of high consistency and batch production. Acoustic pressure gradients in xand y-directions are detected by the cilium, and acoustic pressure gradient in the z direction is detected by the supporting block and beams. Mathematical models of longitudinal stress on the surface of beams and the first three-order natural frequencies of the hydrophone are established. The simulation results prove the accuracy of the mathematical models. Specific structure parameters of hydrophone are determined and then the designed hydrophone is fabricated on a silicon-on-insulator (SOI) wafer. Finally, the sensitivities and directivities of designed hydrophone are tested. The sensitivities of X-channel and Z-channel are -187 dB and -163 dB (0 dB referring to 1 VμPa-1) at 400 Hz, respectively. The test results show that the hydrophone promising in spatial location.

Lansheng Zhang,1,2 Yanwei Chen,3 Hui Wang,3 Xia Zheng,2 Caihong Li,2 Zhengxiang Han3 1Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Jinan, People’s Republic of China; 2Department of Radiation Oncology, the Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, People’s Republic of China; 3Department of Oncology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, People’s Republic of China Background: The roles and related mechanism of miR-376a in breast cancer cell progression are unclear. Methods: Kaplan-Meier plotter analysis was used to analyze the correlation between miR-376a and the overall survival (OS) of breast cancer patients. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to detect miR-376a level in breast cancer cells. Cell viability, transwell migration and invasion, and cell apoptosis were constructed to investigate the effects of miR-376a on breast cancer cells. Luciferase reporter and RNA immunoprecipitation (RIP) were used to explore the targeting of miR-376a on NRP-1. Results: miR-376a expression was positively correlated with the overall survival of breast cancer patients, and significantly decreased in breast cancer cells. Functionally, miR-376a overexpression suppressed cell proliferation, migration and invasion, and promoted cells apoptosis. Additionally, miR-376a could directly target NRP-1 and exerted its effect through NRP-1. Conclusion: miR-376a could suppress breast cancer cell progression via directly targeting NRP-1. Keywords: miR-376a, NRP-1, breast cancer, Wnt/β-catenin migration

Background/Aims: Targeting cancer stem cells (CSCs) is emerging as a promising method for cancer treatment. We previously indicated that knockdown of Neuropilin 1(NRP-1) could inhibit breast cancer cell proliferation. Here, we continue exploring the roles and mechanisms of VEGF-A/NRP-1 axis in breast CSCs formation. Methods: qRT-PCR was used to detect the levels of VEGF-A and NRP-1 in breast cancer sphere cells and wild-type cells. Mammospheres formation, flow cytometry, soft agar colony and tumor formation assays were performed to evaluate the effects of VEGF-A/NRP-1 on breast cancer stemness. Further HUVECs tube formation, cell invasion assays were carried out to detect the effects of VEGF-A/NRP-1 on breast cancer spheres-induced angiogenesis. Finally, Annexin V/PI apoptosis and CCK8 assays were used to detect the effects of VEGF-A/NRP-1 on chemoresistance. Results: Overexpression of VEGF-A or NRP-1 conferred CSCs-related traits in MCF-7 cells, while knockdown of VEGF-A or NRP-1 reduced CSCs-related traits in MDA-MB-231 cells in vitro and in vivo . Notably, VEGF-A acted in a NRP-1 dependent way. Mechanistically, the VEGF-A/NRP-1 axis conferred CSCs phenotype via activating Wnt/β-catenin pathway. Conclusion: our results suggest that VEGF-A/NRP-1 axis could confer CSCs-related traits and chemoresistance.

The cilium MEMS vector hydrophone (CVH) plays an important role in detecting underwater acoustic targets, but there are still problems of low sensitivity and insufficient working bandwidth. In this paper, hollow cilium cylinder vector hydrophone (HCVH) is presented, which can improve sensitivity and working bandwidth within a certain range. Acting as the received acoustic signal structure, a hollow cylinder can not only ensure that sensitivity is improved by increasing the size of area which receives sound, but also reduce its weight to improve the stability of hydrophone. Through the theoretical analysis and the simulation, the relationship between the structure parameters and working performance of the hydrophone is obtained, and the specific size of the sensitive structure is determined. The experimental results show that the sensitivity of HCVH is increased by 8.7 dB in 20–1000 Hz, reaching up to −185.6 dB (re 1 V/µPa) at 1250 Hz. In addition, HCVH has a good directivity.

An excellent hydrophone should have higher sensitivity in its working frequency-band to provide signal with better quality for direction of arrival (DOA). Aiming at the centralized distribution of radiation noise from ships generally below 1 K H z , a Dumbbell-shaped ciliary MEMS vector hydrophone (DCVH) with better sensitivity below 1 K H z is designed in this paper. When detecting the submarine sound signal, Dumbbell-shaped ciliary can obtain the area of receiving sound waves larger than common ciliary structure in the same mass, increase the center of gravity position and increase the moment of force, so as to improve the high sensitivity of hydrophone under the premise of meeting the working frequency-band. In addition, the use of resin as the material for making cilia can bring better performance to hydrophone. Through theoretical analysis and simulation verification by COMSOL5.4, the design is feasible. Finally, DCVH is verified by hydrophone test calibration system, with the sensitivity of - 186.1 d B ( 1 K H z , 0 d B = 1 V / μ P a ), 10.8 d B higher than bionic ciliary MEMS vector hydrophone (CVH), the working frequency-band of 20 H z - 1 K H z , the excellent “8″ character directivity, and concave point depth exceeding 30 d B , which is consistent with theory and simulation results and meets the design requirements.

Because underground load spectra measured work is seldom researched, a large capacity data recorder, also called as “black box”, that can be used underground for a long time and storage machine working condition data has been invented and used. Combined the actual measured data with cutting motor current and voltage and other roadheader parameters, the value of torque that cutting head suffered can be calculated and, the one-dimensional load spectrum in time domain can be drawn. By analyzing, it is found that there may be a static component. Moreover, two-dimension load spectrum based on rain flow count method can be drawn and then it is used to conclude the value of the static load and the range of dynamic load.

In this paper, a bat-shape electronic stethoscope based on MEMS technology is presented. The detector microstructure in bat-shape electronic stethoscope is designed by combining theoretical analysis and finite element method. Visual heart sound signal processing includes circuit and upper computer design. The frequency of the clinical heart sound signal is mostly in the range of 20–600 Hz. The sensitivity of the microstructure, its work-bandwidth and the SNR of the system are the key points of this design. And the final test results showed that the sensitivity of the sensor is −180.7 dB@500 Hz and SNR is 38 dB (17 dB higher than the 3 M electronic stethoscope). Based on theoretical analysis and test results, the bat-shape MEMS electronic stethoscope designed in this paper features small size, high sensitivity, high SNR and easy processing, and has broad prospects in the field of heart sound detection.

A new heterodimer, rynchopeterine F (1), a new natural product, rynchopeterine G (2), and eleven known phenolics were isolated from Blap rynchopetera Fairmaire, a kind of medicinal insect utilized by the Yi and Bai Nationality in Yunnan Province of China. Their structures were established on the basis of extensive spectroscopic analyses (1D and 2D NMR, HR-MS) along with calculated electronic circular dichroism method. Rynchopeterine F was a unusual heterodimer of a 3,4-dihudroxy phenylethanol unit fused to a 3,4-dihudroxy phenylacetyl group through two ester bonds with lactic acid, and rynchopeterine G was a 3,4-dihudroxy phenylethanyl monoester succinate. Attributed to the adjacent dihydroxyl grops, compounds 1 and 2 exhibited significant anti-radical activity with an IC50 value of 3.52 and 7.83 μg/mL for DPPH radical-scavenging, similar with that of the positive controls, vitamin C, 6.92 μg/mL and rutin, 8.28 μg/mL.

For piezo-resistive sensors have outstanding low-frequency response, micro-electro-mechanical system (MEMS) piezo-resistive vector hydrophones play an important role in low-frequency sound waves measurements. However, their signal-noise ratio (SNR) can be decreased by vibration noise. The conventional solution is to suspend the hydrophone elastically, which can reduce the influence of vibration with frequencies higher than the natural frequency of the elastic element used for suspension. However, this approach has little effect on reducing low-frequency vibration noise. To overcome this problem, a novel hydrophone structure with a large-volume supporting block is proposed in this study. When the hydrophone is subject to vibration, the actions of the supporting block and cilium on the piezo-resistors counteract each other. Therefore, the proposed hydrophone can effectively reduce output voltages caused by vibration. Mathematical models of this new hydrophone are established to verify the feasibility of the method. Simulations are performed and found to be in accordance with the mathematical models. The experimental results clearly demonstrate that the proposed hydrophone can dramatically reduce vibration noise without reducing sensitivity to sound.

Others and ours studies have established the promoting roles of NRP-1 (neuropilin-1) in breast cancer, however, the underlying mechanisms by which NRP-1 is regulated are still confused. Here, bioinformatics analysis indicated that RNA binding protein PUM2 could bind to NRP-1 mRNA. Clinical samples showed that PUM2 expression was significantly increased in breast cancer tissues, negatively correlated with the overall survival and relapse-free survival of breast cancer patients, and positively correlated with NRP-1 expression. Meanwhile, PUM2 expression was remarkably increased in non-adherent spheroids. in vitro experiments demonstrated that PUM2 knockdown attenuated the stemness of breast cancer cells, evident by the decrease of spheroid formation capacity, ALDH1 activity and stemness marker expression. Mechanistically, RNA immunoprecipitation (RIP) and luciferase reporter analysis indicated that PUM2 competitively bound to NRP 3'UTR with miR-376a, which had been previously confirmed by us to suppress the stemness of breast cancer cells, and increased NRP-1 mRNA stability and expression. Furthermore, ectopic expression of NRP-1 or miR-376a knockdown rescued the inhibitory effects of NRP-1 knockdown on the stemness of breast cancer cells. Thus, our results suggest that PUM2 could facilitate the stemness of breast cancer cells by competitively binding to NRP-1 3'UTR with miR-376a.

Patrinia heterophylla Bunge, a traditional Chinese herb, has long been used for therapy of many kinds of diseases, including cancer. Its extract or pure compound has displayed anti-proliferative effect on cancer cells as well. However, the underlying mechanism(s) by which P. heterophylla Bunge exhibited anti-tumor activity in vivo remains to be further elucidated. Herein, we investigated the effect of total flavonoid from P. heterophylla Bunge, named as PHBF, on mice bearing cervical cancer. As a result, the oral administration of PHBF (250 and 500 mg/kg BW) had significant inhibitory effect on tumor volume and weight. In addition, PHBF treatment increased thymus index of tumor-bearing mice in a dose-dependent manner ( P+ and CD8+ T lymphocytes in peripheral blood mononuclear cells (PBMC) of tumor-bearing mice. Furthermore, we observed that the serum level of interferon gamma (IFN-γ) and interleukin-2 (IL-2) was significant higher in mice treated with PHBF than those of control group, implicating that PHBF could function as an immunomodulatory agent. Taken together, these data suggested that PHBF harbored anti-tumor properties against cervical cancer and up-regulated immune response, therefore paving a path to develop as a potential therapeutic and preventive agent for cervical treatment.

Rationale: Using magnetic resonance imaging (MRI), we diagnosed pneumoconiosis by identifying the content and distribution of hydrogen protons in the water molecules in different tissues and lesions. Patient concerns: 25 cases of CWP patients with progressive massive fibrosis (PMF) lesions. Diagnoses: Patients were correctly diagnosed, with one case each of Phase I and II pneumoconiosis and 23 cases of Phase III pneumoconiosis. Interventions: None. Outcomes: Through MRI, 39 PMF pneumoconiosis lesions exhibited equal, low or equally low, and uneven signals on T2WI and fat suppression (SPIR) (38/39, 37/39). Lessons: MRI has good specificity to identify the characteristics of PMF lesions of CWP, as well as has high application value for the differential diagnosis of lung cancer and other lung tumor-like lesions.

Maps of pollen data have long been unavailable for continental Asia despite their importance for paleoecological and paleoclimatic studies. Pollen data from 65 Holocene sites have allowed the mapping of eight pollen taxa and seven time slices for Northeast China. These pollen maps show significant vegetation changes during the last 10,000 years in the current forest regions of Northeast China, with the early Holocene characterized by widely distributed Betula trees, the mid-Holocene by the development of temperate deciduous forest mainly consisting of Quercus and Ulmus trees, and the late Holocene by the marked increase in the abundance of Pinus trees and the development of temperate mixed conifer and deciduous forest. An unexpected finding from the pollen mapping research is the south-to-north propagation of the mid-to-late-Holocene forest decline, which may have been caused by the persistent human activities and the gradually northward expansion of agriculture during the last 5000 years. It is thus evident that caution has to be taken when reconstructing the mid-to-late-Holocene climates from pollen records in some regions of Northeast China. The classic paleoclimate reconstruction for the southern part of the study area and possibly for North and Northwest China needs to be re-evaluated.