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In response to the problems of small pressure monitoring range, low sensitivity, and high cost of existing fiber optic pressure sensors, an improved fiber optic pressure sensor is designed. A strain fiber optic grating is stuck on the cantilever beam and a temperature fiber optic grating is suspended (to make it stress free). The limit cover below the cantilever beam places the spring, corrugated pipe pressure cover, and corrugated pipe cover inside it. The inner upper plane of the limit cover contacts the upper plane of the spring, and the lower plane of the spring contacts the corrugated pipe pressure cover. When external pressure reaches the corrugated pipe through the pipeline at the bottom of the corrugated pipe, the high pressure causes it to undergo axial deformation. The deformation in turn compresses the spring. Finally, the spring undergoes deformation and transmits force to the cantilever beam, changing the stress situation of the strain grating. A spring with a larger stiffness coefficient is added to the single-layer corrugated pipe to limit its deformation when external pressure is generated, allowing the corrugated pipe and spring to jointly transmit pressure to the cantilever beam. The experimental test results show that the improved sensor has a pressure monitoring range of 0-5 MPa, which is 5 times higher than before. The sensitivity of the sensor is 0.379 98 nm/MPa, and the measurement error is within 0.02 MPa. The improved pressure sensor is validated in a water pipeline underground. The results show that compared with the measurement results of high-precision electronic pressure gauges, the pressure demodulation error of the sensor is within 0.02 MPa.

Background Postmenopausal osteoporosis (PMPO) is the most familiar type of osteoporosis, a silent bone disease. Casticin, a natural flavonoid constituent, improves osteoporosis in animal model. Nevertheless, the potential mechanism remains to be further explored. Methods A model of PMPO was established in rats treated with ovariectomy (OVX) and RAW 264.7 cells induced with receptor activator of nuclear factor kappa-B ligand (RANKL). The effect and potential mechanism of casticin on PMPO were addressed by pathological staining, measurement of bone mineral density (BMD), three-point bending test, serum biochemical detection, filamentous-actin (F-actin) ring staining, TRAcP staining, reverse transcription quantitative polymerase chain reaction, western blot and examination of oxidative stress indicators. Results The casticin treatment increased the femoral trabecular area, bone maturity, BMD, elastic modulus, maximum load, the level of calcium and estrogen with the reduced concentrations of alkaline phosphatase (ALP) and tumor necrosis factor (TNF)-α in OVX rats. An enhancement in the F-actin ring formation, TRAcP staining and the relative mRNA expression of NFATc1 and TRAP was observed in RANKL-induced RAW 264.7 cells, which was declined by the treatment of casticin. Moreover, the casticin treatment reversed the reduced the relative protein expression of Nrf2 and HO-1 and the concentrations of superoxide dismutase and glutathione peroxidase, and the increased content of malondialdehyde both in vivo and in vitro. Conclusion Casticin improved bone density, bone biomechanics, the level of calcium and estrogen, the release of pro-inflammatory factor and oxidative stress to alleviate osteoporosis, which was associated with the upregulation of Nrf2/HO-1 pathway. [ABSTRACT FROM AUTHOR]

Objective: Wear particles induce inflammation and the further osteolysis around the prosthesis, has been proven to be the main cause of aseptic hip joint loosening. In this research, we aimed to clarify whether human umbilical cord mesenchymal stem cells (HUCMSCs) could inhibit the titanium particles‐induced osteolysis and shed light upon its mechanism. Methods: The expression of chemokine (C‐C motif) ligand 2 (CCL2), chemokine (C‐C motif) ligand 3 (CCL3) and chemokine (C‐C motif) ligand 5 (CCL5) were examinjed in clinical specimens of aseptic hip prosthesis loosening patients. Local injection of lentivirus that knocked down CCL2 or CCL3 in a cranial osteolysis mice model were used to exam the effect of CCL2 and CCL3 on titanium particles‐induced osteolysis in vivo. Transwell assay was used to examine the effect of CCL2 and CCL3 on titanium particles‐induced activation of macrophage in vitro. Furthermore, the therapeutic effect of HUCMSCs, and exosomes from HUCMSCs were also examed in vivo and vitro. Immunohistochemical and real‐time PCR were used to examine the expression of relative pathways. Analysis of variance (ANOVA) and Student–Newman–Keuls post hoc t test were used to analyze the results and determine the statistical significance of the differences. Results: Results showed that titanium particles caused the osteolysis at the mice cranial in vivo and a large number of macrophages that migrated, while local injection of HUCMSCs and exosomes did inhibit the cranial osteolysis and migration. An exosome inhibitor GW4869 significantly increased the osteolysis area in the mice cranium osteolysis model, and increased the number of migrated macrophages. Immunohistochemical results suggested that the expression of CCL2, CCL3 and CD68 in the cranial in Titanium particles mice increased significantly, but was significantly reduced by HUCMSCs or exosomes. HUCMSC and exosomes down‐regulate the expression of CCL3 in vitro and in vivo. Conclusion: HUCMSCs and HUCMSC‐derived exosomes could suppress the titanium particles‐induced osteolysis in mice through inhibiting chemokine (C‐C motif) ligand 2, chemokine (C‐C motif) ligand 3. [ABSTRACT FROM AUTHOR]

In the practical processes of coal mines and tunnel, rectangular roadways are widely used in the underground environment. However, the stress distribution law of the rock mass around the rectangular roadways is relatively complicated that is influenced by different parameters, such as the in situ stress, geological structure, and properties of the surrounding rock mass. It is extremely significant to conduct systematic and in-depth research regarding the stress distribution and deformation failure mechanism of the rock mass around the rectangular roadways. Based on theoretical analysis, the stress distribution law of the surrounding rock of rectangular roadway under different rock mass strength grades is studied directly through rectangular roadway in this paper. This further reveals the distribution law of secondary stress field after excavation of rectangular roadway. A coal mine intends to excavate a roadway in rock mass, and then, the rectangular roadway is simulated by FLAC3D software. Then, the strain distribution and failure types of roadway surrounding rock under different rock mass properties are obtained. The results show that the failure of rectangular roadway is mainly shear failure and tensile failure. The roof and floor of roadway are mainly tensile failure, and the side of roadway is mainly shear failure. Moreover, the stress shifting and distribution of the rock mass around rectangular roadways is a complicated dynamic variation process. The damage degree of the floor and roof of the rectangular roadway is greater than that of the two sides of the roadway. Its variation is mainly related to the strength of surrounding rock mass. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis has influenced millions of people, especially postmenopausal women, which has become a big burden to the whole world. Although the diverse roles of casticin (CAS) on different diseases were identified, whether it was implicated with osteoporosis was unknown. Methods: A rat model of osteoporosis was established through dexamethasone (DEX) treatment and a cell model reflecting the osteogenic and osteoclast induction was constructed in bone marrow stromal cells (BMSCs). The calcification at the late stage of induction was measured via Alizarin Red S staining. Western blot was applied to evaluate the levels of proteins. Results: Hematoxylin and eosin staining revealed that the number of bone trabecular in DEX‐induced osteoporosis rats was decreased, while increased doses of CAS treatment elevated the number of bone trabecular. CAS treatment alleviated DEX‐induced osteoporosis in rats. Moreover, we found that CAS inhibited the nuclear factor‐κB/mitogen‐activated protein kinase (NF‐κB/MAPK) pathway. In addition, CAS promoted osteogenic differentiation of BMSCs and reduced osteoclastogenesis of bone marrow monocytes. Finally, CAS was observed to retard the receptor activator of NFκ‐B ligand‐induced NF‐κB/MAPK pathway. Conclusion: CAS promoted osteogenic differentiation of BMSCs and improved osteoporosis in rats by regulating the NF‐κB/MAPK pathway. This might shed a light into using CAS as a drug treating osteoporosis in the future. [ABSTRACT FROM AUTHOR]

A water environment quality evaluation and pollution source analysis can quantitatively examine the relationship among water pollution, resources, and the economy, and investigate the main factors affecting water quality. This paper took COD, NH3-N, and TP of the Tuojiang River as the research objects. The water environment quality evaluation and pollution source analysis of the Tuojiang River Basin were conducted based on the grey water footprint, decoupling theoretical model, and correlation analysis method. The results showed that grey water footprint decreased, and the water environment quality improved. Among the pollution sources of the grey water footprint, TP accounted for the highest proportion. Moreover, the economic development level and the water environment were generally in a state of high-quality coordination. Farmland and stock breeding pollution accounted for the largest proportion of agricultural pollution and were thus the main source of the grey water footprint. The results of Pearson's correlation analysis indicated that the source of the pollutants were the imported pollution from the tributaries and agricultural pollution (especially stock breeding and farmland irrigation). These results showed that the quality of the water environment was improving, and the main factors affecting the water environment were stock breeding and farmland pollution in agriculture. This study presents a decision-making basis for strengthening the ecological barrier in the Yangtze River. [ABSTRACT FROM AUTHOR]

Objective : Osteonecrosis of the femoral head (ONFH) is a common condition that is encountered in clinical practice, and yet, little is known about its characteristics and manifestations in the brain. Therefore, in this study, we aimed to use resting-state functional magnetic resonance imaging (rs-fMRI) to investigate the spatial patterns of spontaneous brain activity in the brain of ONFH patients. Methods : The study included ONFH patients and healthy controls. The pattern of intrinsic brain activity was measured by examining the amplitude of low-frequency fluctuations (ALFF) of blood oxygen level-dependent signals using rs-fMRI. Meanwhile, we also used Harris hip scores to evaluate the functional performance of ONFH patients and healthy controls. Result : Ten ONFH patients and 10 health controls were investigated. We found global ALFF differences between the two groups throughout the occipital, parietal, frontal, prefrontal, and temporal cortices. In the ONFH patients, altered brain activity was found in the brain regions in the sensorimotor network, pain-related network, and emotion and cognition network. The results of the correlation investigations also demonstrated that the regions with ALFF changes had significant correlations with the functional performance of the patients evaluated by Harris hip scores. Conclusions : Our study has revealed the abnormal pattern of brain activity in ONFH patients, and our findings could be used to aid in understanding the mechanisms behind the gait abnormality and intractable pain associated with ONFH at the central level. [ABSTRACT FROM AUTHOR]

The induction of pluripotent stem cells (iPSCs) by defined factors is poorly understood stepwise. Here, we show that histone H3 lysine 9 (H3K9) methylation is the primary epigenetic determinant for the intermediate pre-iPSC state, and its removal leads to fully reprogrammed iPSCs. We generated a panel of stable pre-iPSCs that exhibit pluripotent properties but do not activate the core pluripotency network, although they remain sensitive to vitamin C for conversion into iPSCs. Bone morphogenetic proteins (BMPs) were subsequently identified in serum as critical signaling molecules in arresting reprogramming at the pre-iPSC state. Mechanistically, we identified H3K9 methyltransferases as downstream targets of BMPs and showed that they function with their corresponding demethylases as the on/off switch for the pre-iPSC fate by regulating H3K9 methylation status at the core pluripotency loci. Our results not only establish pre-iPSCs as an epigenetically stable signpost along the reprogramming road map, but they also provide mechanistic insights into the epigenetic reprogramming of cell fate. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (T2DM) is a metabolic disease accompanied by a series of diseases such as diabetic nephropathy. The drug pair (HS) of Astragalus Radix (HQ) and Dioscoreae Rhizoma (SY) was designed by Dr. Shi Jinmo to improve the treatment of T2DM. However, the exact mechanism involved requires further clarification. In this work, 1H-NMR–based metabonomics and network pharmacology were adopted. Metabolic profiling indicated that the metabolic perturbation was reduced after HS treatment. The results found 21 biomarkers. According to the network pharmacology, we found that the regulation of T2DM was primarily associated with 18 active compounds in HS. These active compounds mainly had an effect on 135 targets. Subsequently, combining network pharmacology and metabonomics, we found four target proteins, which indicated that HS has potential hypoglycemic effects through regulating monoamine oxidases B (MAOB), acetyl-CoA carboxylase 1 (ACACA), carbonic anhydrase 2 (CA2), and catalase (CAT). In conclusion, the result showed that these four targets might be the most relevant targets for the treatment of T2DM with HS. This study clarified the mechanism of HS in the treatment of T2DM and also confirmed the feasibility of combining metabonomics and network pharmacology to study the mechanisms of traditional Chinese medicine (TCM). In the future, this approach may be a potentially powerful tool to discovery active components of traditional Chinese medicines and elucidate their mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, poly(methyl methacrylate) (PMMA)/organically modified montmorillonite (O-MMT) composite microfibers were firstly prepared by emulsion polymerization combined with electrospinning, and then coated by nanosize titanium dioxide (TiO2) using RF magnetron sputter technique. The modified surfaces of PMMA/O-MMT composite microfibers were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), UV–vis spectroscopy and drop shape analyzer. Finally, the photocatalytic properties of TiO2 coated PMMA/O-MMT composite microfiber membranes were evaluated by degradation of methylene blue(MB) under UV illumination. The experimental results revealed that anatase-TiO2 and rutile-TiO2 nanoparticles were well spread and physically deposited on the surface of PMMA/O-MMT microfibers, and the wettability of the PMMA/O-MMT composite microfibers was improved after surface modification by sputter coating. Furthermore, the PMMA/O-MMT microfibers membrane coated with TiO2 performed well in photocatalytic degradation of MB. [Copyright &y& Elsevier]

As a direct band gap photocatalyst, BiOF has attracted considerable attention in photocatalytic field due to its unique layered structures. However, it is highly challenging to prepare BiOF with excellent photocatalytic performance. In this paper, a facile and efficient PVA-assisted hydrothermal preparation of BiOF was reported. The samples were characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (DRS), Brunauer-Emmett-Teller method (BET), surface photovoltage (SPV) spectroscopy and particle size analyzer. The photocatalytic activity of PVA-BiOF was evaluated by decolorization of methyl orange (MO) aqueous solution. The results reveal that photocatalytic activity of PVA-BiOF is ten times of that of the reference BiOF. The enhancement photocatalytic performance of PVA-BiOF can be attributed to the enhanced surface area and the accelerated formation of O 2 − . [ABSTRACT FROM AUTHOR]