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This paper aims to study the measurement accuracy of Rayleigh scattering lidar (light detection and ranging) based on a ship platform and analyze the influence of the laser beam uncertainty on the temperature inversion results. Taking the ship platform roll data as a reference, the Rayleigh scattering lidar oscillating model is simplified to a sine function, and the inversion accuracy of atmospheric temperature is analyzed under different settled observation angles and different roll angles. When the settled observation angle is 0° and the roll angle amplitudes are 10°, 20°, and 30°, the maximum deviations of the temperature within the height range of 30–80 km are 3.47 K, 13.73 K, and 22.78 K, respectively, and the average deviations are 2.35 K, 9.09 K, and 12.95 K, respectively. When the observation angle is set to 30° and the roll angle amplitudes are 10°, 20°, and 30°, the maximum deviations of the temperature within the height range of 30–80 km are 11.75 K, 27.49 K, and 53.50 K, respectively, and the average deviations are 11.05 K, 13.88 K, and 16.12 K, respectively. The results of this paper show that ship platform rolling greatly influences the measurement of atmospheric temperature, which provides a certain data reference for the construction and use of Rayleigh scattering lidar in the ship platform. [ABSTRACT FROM AUTHOR]

This study is to investigate the role of regulatory B (Breg) cells in cervical cancer. In total, 70 cases of cervical cancer, 52 cases of cervical intraepithelial neoplasia (CIN), and 40 normal controls were enrolled. The percentage of Breg cells was detected by flow cytometry. Serum levels of IL-10 were measured by ELISA. The correlation between Breg cells and the clinical characterizations of cervical cancer was analyzed. The inhibition effect of Breg cells on CD8+ T cells was tested by blocking IL-10 in vitro. The percentage of CD19+CD5+CD1d+ Breg cells and the level of IL-10 of patients with cervical cancer or CIN were significantly higher than those in the control group (P<0.05). And the postoperative levels of Breg cells and IL-10 were significantly lower than the preoperative levels (P<0.05). Breg cells and the IL-10 level were positively correlated in cervical cancer patients (r=0.516). In addition, the Breg cell percentage was closely related to the FIGO stages, lymph node metastasis, tumor differentiation, HPV infection, and the tumor metastasis of cervical cancer (P<0.05). The Breg cell percentage was negatively correlated with CD8+ T cells of cervical cancer patients (r=‐0.669). The level of IL-10 in the culture supernatant of Bregs treated with CpG was significantly higher than that of non-Bregs (P<0.05). After coculture with Bregs, the quantity of CD8+ T cells to secrete perforin and Granzyme B was significantly decreased, and this effect was reversed after blocking IL-10 by a specific antibody. Breg cells are elevated in cervical cancer and associated with disease progression and metastasis. Moreover, they can inhibit the cytotoxicity of CD8+ T cells. [ABSTRACT FROM AUTHOR]

Composite structures combine the advantages of multiple materials, which can improve the structural crashworthiness performance. This paper aims to combine the high strength of carbon fibre-reinforced plastic (CFRP), the excellent ductility of aluminium alloy (Al), and the good compressibility of polyurethane (PU) foam. Quasi-static compression and low-velocity impact tests were conducted on thin-walled tubes made of single materials and composite sandwich structures made of multi-materials, namely Al-PU-Al, Al-PU-CFRP, CFRP-PU-Al, and CFRP-PU-CFRP. The structural failure modes and crashworthiness indicators were analysed and compared under different loadings. The results showed that the CFRP thin-walled tube exhibited a progressive damage and failure mode, and the resultant force changed smoothly. The CFRP tube possessed a larger mean crushing force and specific energy absorption than the corresponding aluminium tube. Composite structures exhibited more stable deformation mode and higher energy absorption, compared with the sum of linear superposition (SLS) of individual components, due to the interaction effects among components. Among the designed four combinations, CFRP-PU-CFRP exhibited an ideal energy absorption under both quasi-static and dynamic impact, while CFRP-PU-Al produced the second highest specific energy absorption (SEA), with an increment of 42.0% compared with Al-PU-Al. With full consideration of crashworthiness performance and economic cost, CFRP-PU-Al can be recommended as an impact energy absorber for vehicles due to its lower economic cost than CFRP-PU-CFRP. [ABSTRACT FROM AUTHOR]

Composite structures have drawn growing attention for their outstanding characteristics benefiting from the combination of multi materials. This paper aims to investigate the crushing performance of a hybrid system involving an outer thin-walled tube made of carbon fibre-reinforced plastic (CFRP), a medial polyurethane (PU) foam and an inner thin-walled tube made of aluminium alloy (Al). The elastoplastic model of Al, the continuous damage model of CFRP and the compressible foam model of PU were established with assistance of universal material tests. The finite element model of the composite structure, namely CFRP-PU-Al, was validated by the experimental study. Based upon the reliable numerical modelling, the parametric study was carried out for exploring the effects of the wall thickness, diameter and ply orientation of the outer CFRP tube, namely CFRP-O, on the crushing behaviours of the composite structure. It was found that increasing the diameter or wall thickness of CFRP-O was helpful to increase the mean crushing force and energy absorption of CFRP-PU-Al, however, the overall specific energy absorption of the composite sandwich structure was limited by the characteristics of constitutive materials. Compared with the diameter, the wall thickness had a higher impact on the energy absorption characteristics, and increasing the diameter may decrease the specific energy absorption due to the increase of the overall structural mass. In terms of the ply orientation, the composite structure with stacking sequence of [0°/45°] 3 possessed higher mean crushing force and energy absorption than the structure with stacking sequence of [0°/90°] 3 under axial compression in this study. • Composite sandwich structures made of multi-materials were designed and fabricated. • Material constitutive models were established and the finite element model was validated by experiments. • The parametric effects of CFRP thin-walled structure on the crushing performance of the composite sandwich structure were clarified. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the associations of physical activity trajectories with maternal fatigue. Pregnant women provided objectively assessed physical activity data by Pregnancy Physical Activity Questionnaire four times. Fatigue scale-14 was used to assess fatigue during pregnancy. Growth mixture modelling characterized physical activity trajectories across pregnancy. The generalized estimating equations was used to analyze the relationship between different physical activity profiles and fatigue in pregnant women. A total of 626 pregnant women were included in analysis in a teaching hospital in Nantong city. Fatigue (total, mental and physical) was not different between two groups based on total energy expenditure of PA (constantly high vs. constantly low). The pregnant women in "constantly high household PA" group had the higher fatigue compared to "constantly low household PA" (P < 0.05) and "constantly medium household PA" (P < 0.05). The pregnant women in "constantly high sport PA" group had lower fatigue compared to "constantly low sport PA" (P < 0.05). Household PA and sport PA were still an independent influencing factor for fatigue after controlling for confounding variables. Specifically, we observed that higher household PA and lower sport PA were associated with higher fatigue during pregnancy. [ABSTRACT FROM AUTHOR]

Background: To explore the value of umbilical artery cord blood glucose (UACBG) in predicting hypoglycemia in gestational diabetes mellitus (GDM) and other at-risk newborns, and to provide a cut-off UACBG value for predicting hypoglycemia occurrence. Methods: In this prospective study, we enrolled at-risk infants delivered vaginally, including neonates born to mothers with GDM, premature, macrosomic, and low birth weight. We separated the infants into GDM group and other at-risk group. All subjects underwent UACBG measurement during delivery. Neonatal peripheral blood glucose measurement was performed at 0.5 and 2 h after birth. The predictive performance of UACBG for neonatal hypoglycemia was assessed using receiver operating characteristic curve (ROC), area under curve (AUC), sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV). Results: 916 newborns were included, with 538 in GDM group and 378 in other at-risk group. 85 neonates were diagnosed hypoglycemia within 2 h after birth, including 36 belonging to GDM group and 49 to other at-risk group. For hypoglycemia prediction within 2 h, the best cut-off of UACBG was 4.150 mmol/L, yielding an AUC of 0.688 (95% CI 0.625–0.751) and a NPV of 0.933. In detail, the AUC was 0.680 in GDM group (95% CI 0.589–0.771), with the optimal cut-off of 4.150 mmol/L and a NPV of 0.950. In other at-risk group, the AUC was 0.678(95% CI 0.586–0.771), the best threshold was 3.950 mmol/L and the NPV was 0.908. No significant differences were observed between GDM group and other at-risk group in AUC at 0.5 h, 2 h and within 2 h. Conclusions: UACBG has a high NPV for predicting neonatal hypoglycemia within 2 h after birth. It was implied that individuals with cord blood glucose levels above the threshold were at lower risk for hypoglycemia. UACBG monitoring provides evidence for subsequent classified management of hypoglycemia. [ABSTRACT FROM AUTHOR]

Reasonable evaluation of evapotranspiration (ET) is crucial for optimizing agricultural water resource management. In the study, we utilized the Data Mining Sharpener (DMS) model; the Landsat thermal infrared images were sharpened from a spatial resolution of 100 m to 30 m. We then used the Surface Energy Balance System (SEBS) to estimate daily ET during the winter wheat growing season in the People's Victory Irrigation District in Henan, China. It was concluded that the spatiotemporal patterns of land surface temperature and daily evapotranspiration remained consistent before and after sharpening. Results showed that the R2 value between the ET of 30 m spatial resolution and the value by eddy covariance method reached 0.814, with an RMSE of 0.516 mm and an MAE of 0.245 mm. All of these were higher than those of 100 m spatial resolution (R2 was 0.802, the RMSE was 0.534 mm, and the MAE was 0.253 mm). Furthermore, the daily ET image with a 30 m spatial resolution exhibited clear texture and distinct boundaries, without any noticeable mosaic effects. The changes in surface temperature and ET were more consistent in complex subsurface environments. The daily evapotranspiration of winter wheat was significantly higher in areas with intricate drainage systems compared to other regions. During the early growth stage, daily evapotranspiration decreased steadily until the overwintering stage. After the greening and jointing stages, it began to increase and peaked during the sizing period. The correlation between net solar radiation and temperature with ET was significant, while relative humidity and soil moisture were negatively correlated with ET. Throughout the growth period, net solar radiation had the greatest effect on ET. [ABSTRACT FROM AUTHOR]

Duplications of Methyl CpG binding protein 2 (MECP2) -containing segments lead to the MECP2 duplication syndrome, in which severe autistic symptoms were identified. Whether adult neurogenesis may play a role in pathogenesis of autism and the role of MECP2 on state determination of adult neural stem cells (NSCs) remain largely unclear. Using a MECP2 transgenic (TG) mouse model for the MECP2 duplication syndrome, we found that adult hippocampal quiescent NSCs were significantly accumulated in TG mice comparing to wild type (WT) mice, the neural progenitor cells (NPCs) were reduced and the neuroblasts were increased in adult hippocampi of MECP2 TG mice. Interestingly, we found that parvalbumin (PV) positive interneurons were significantly decreased in MECP2 TG mice, which were critical for determining fates of adult hippocampal NSCs between the quiescence and activation. In summary, we found that MeCP2 plays a critical role in regulating fate determination of adult NSCs. These evidences further suggest that abnormal development of NSCs may play a role in the pathogenesis of the MECP2 duplication syndrome. [ABSTRACT FROM AUTHOR]

During a woman's reproductive period, the endometrial tissue is shed and regenerated every month to prepare for pregnancy or for the next cycle. The aim of the present study was to isolate, culture and characterize human endometrial cells (ECs) derived from menstrual blood (MB) and the endometrium (E). MB-derived ECs (MB-ECs) were isolated from women's MB. E-derived ECs (E-ECs) were isolated from women's endometrial tissues. The present study investigated the epithelial cell marker cytokeratin 18 (CK18) in MB-ECs and E-ECs. Cell proliferation analyses indicated that E-ECs (population doubling time, 20.85 h) grew faster than MB-ECs (population doubling time, 22.05 h; P<0.05). Cell migration ability was found to be significantly greater for MB-ECs than for E-ECs at 48 h (P<0.01). MB-ECs incubated with TGF-β1 (3 ng/ml) exhibited significantly decreased CK18 mRNA expression (P<0.01), and significantly increased vimentin (Vim) mRNA (P<0.05) and protein (P<0.01) expression at 6 and 12 h, respectively. E-EC incubation with TGF-β1 (3 ng/ml) significantly decreased CK18 mRNA expression (P<0.01) at 12 h and significantly increased Vim mRNA (P<0.01) and protein expression (P<0.05) at 6 h. The present results indicated that MB-ECs and E-ECs were biologically different, and that epithelial-mesenchymal transdifferentiation could be induced by TGF-β1 treatment. [ABSTRACT FROM AUTHOR]

To realize a soft-switching inverter with the advantages of a simple structure, high efficiency, low-voltage stress, and easy to control, a novel parallel resonant dc-link inverter with the function of pulse current regeneration is proposed in this paper. All switches in the inverter main circuit can achieve zero-voltage switching (ZVS) turn-on and ZVS turn-off. In addition, all switches in the auxiliary commutation circuit (ACC) can achieve soft switching. The power in the ACC is small. Freewheeling diodes in the inverter turn off under zero current condition, which can reduce the reverse recovery loss of freewheeling diodes. In addition, the bulk capacitors are avoided in the circuit and there is no neutral point potential variation problem. At the same time, the zero-voltage duration is independent of the load current, and the time of transition can be selected freely. According to the equivalent circuits in different operation modes under the proposed modulation strategy, the operation principle, soft-switching implementation condition, and parameter design procedure of the proposed inverter are analyzed successively in this paper. Finally, a 10 kW, 10 kHz soft-switching inverter prototype with insulated gate bipolar transistor based switches is built. Experimental results are given to demonstrate the validity and features of the soft-switching inverter. [ABSTRACT FROM AUTHOR]

The DSSAT model, integrated the calibrated Hargreaves ET model and dynamic crop coefficient, was run with the generated weather data by SDSM4.2 and CanESM2 to predict the potential yield and crop water requirement (ETC) of winter wheat in the Huang-Huai-Hai Plain in China under RCP4.5 and RCP8.5 scenarios. The results showed that the spatial distribution of potential yield in the future under RCP4.5 and RCP8.5 were similar, characterized by an increasing trend from the northwest inland to the southeast coast. The spatial distribution of ETC decreased gradually from the Shandong Peninsula to the surrounding area, and the minimum ETC was observed in the southern part of Huang-Huai-Hai Plain. The potential yield, ETC, and effective precipitation during winter wheat growing seasons might increase in the future under RCP4.5, while irrigation water requirements (IWR) would decrease. Under RCP8.5, the effective precipitation during the wheat growing seasons decreased first and then increased. However, the potential yield, ETC, and IWR of winter wheat increased first and then decreased. This study can provide some scientific evidence to mitigate the negative effects of climate change on agricultural production and water use in the Huang-Huai-Hai Plain. [ABSTRACT FROM AUTHOR]

Fos-related antigen-1 (FRA-1) is a member of activator protein-1 (AP-1) transcription factor superfamily, and FRA-1 is highly expressed in colon cancer, breast cancer, gastric cancer, lung cancer, bladder cancer, and other tumors. The expression level of FRA-1 is closely related to the processes of tumor cell proliferation, apoptosis, transformation, migration, and invasion, which is a potential therapeutic target and prognostic factor for many tumors. Clarifying the detailed mechanism of action of FRA-1 could provide the theoretical basis for tumor diagnosis, treatment, and prognosis, and is of great significance for the study of tumor etiology and pathogenesis. In this paper, the expression levels and influencing factors of FRA-1 in various tumor tissues and cells are summarized, as well as the effect of FRA-1 expression level on the biological behavior of tumor cells and the signal transduction mechanism. At the same time, the signal transduction mechanism of FRA-1 in inflammation was expounded. In addition, the related metabolites, drugs and non-coding RNA that affect the expression and function of FRA-1 were summarized. Finally, it illustrates that FRA-1 may be taken as a key factor for tumor prognosis and a potential therapeutic target. This review provides a theoretical basis for the systematic understanding of the relationship between FRA-1 and tumors, its function, and possible mechanism. [Display omitted] • FRA-1 is closely related to the processes of tumor cell proliferation, apoptosis, transformation, migration, and invasion. • FRA-1 plays a key role in regulating inflammatory reaction, and interleukin signal transduction related gene expression. • FRA-1 can promote the proliferation or apoptosis of cancer cells by regulating PI3K/AKT and other signaling pathways. • Some drugs, non-coding RNA and other small molecules can regulate the expression and function of FRA-1. [ABSTRACT FROM AUTHOR]

In this study the principal component analysis (PCA) and geographically weighted regression (GWR) are combined to estimate the spatial distribution of water requirement of the winter wheat in North China while the effect of the macro- and micro-topographic as well as the meteorological factors on the crop water requirement is taking into account. The spatial distribution characteristic of the water requirement of the winter wheat in North China and its formation are analyzed based on the spatial variation of the main affecting factors and the regression coefficients. The findings reveal that the collinearity can be effectively removed when PCA is applied to process all of the affecting factors. The regression coefficients of GWR displayed a strong variability in space, which can better explain the spatial differences of the effect of the affecting factors on the crop water requirement. The evaluation index of the proposed method in this study is more efficient than the widely used Kriging method. Besides, it could clearly show the effect of those affecting factors in different spatial locations on the crop water requirement and provide more detailed information on the region where those factors suddenly change. To sum up, it is of great reference significance for the estimation of the regional crop water requirement. [ABSTRACT FROM AUTHOR]