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In order to meet the requirements of high-precision vehicle positioning in complex scenes, an observation noise adaptive robust GNSS/MIMU tight fusion model based on the gain matrix is proposed considering static zero speed, non-integrity, attitude, and odometer constraint models. In this model, the robust equivalent gain matrix is constructed by the IGG-Ⅲ method to weaken the influence of gross error, and the on-line adaptive update of observation noise matrix is carried out according to the change of actual observation environment, so as to improve the solution performance of filtering system and realize high-precision position, attitude and velocity measurement when GNSS signal is unlocked. A real test on a road over 600km demonstrates that, in about 100km shaded environment, the fixed rate of GNSS ambiguity resolution in the shaded road is 10% higher than that of GNSS only ambiguity resolution. For all the test, the positioning accuracy can reach the centimeter level in an open environment, better than 0.6m in the tree shaded environment, better than 1.5m in the three-dimensional traffic environment, and can still maintain a positioning accuracy of 0.1m within 10s when the satellite is unlocked in the tunnel scene. The proposal and verification of the algorithm model show that low-cost MIMU equipment can still achieve high-precision positioning when there are scene feature constraints, which can meet the problem of high-precision vehicle navigation and location in the urban complex environment.

Citrate is one of the most important metabolites determining the flavour of citrus fruit. It has been reported that nitrogen supply may have an impact on acid level of fruit. Here, the relationship between nitrogen metabolism and citrate catabolism was studied in pumelo juice sacs. Differences in metabolites, gene expression and flux distributions were analyzed in juice sacs incubated in medium with and without NH 4 +. Compared with those incubated with NH 4 +, juice sacs under nitrogen deficiency exhibited enhanced flux through phosphoenolpyruvate carboxykinase (PEPCK) and accelerated consumption of citrate, while the other two TCA cycle efflux points, through malic enzyme (ME) and glutamate dehydrogenase (GDH), were both repressed. Consistent with the estimated fluxes, the expression of PEPCK1 was upregulated under nitrogen deficiency, while that of GDH1 , GDH2 , NAD-ME1 and NADP-ME2 were all repressed. Thus, we propose that PEPCK1 contributes to citrate degradation under nitrogen limitation. • Metabolism in pomelo juice sacs was analyzed systematically and quantitatively with stoichiometric metabolic flux analysis. • Nitrogen deficiency accelerated decrease in citrate content of juice sacs. • Nitrogen deficiency enhanced reaction of PEPCK and suppressed other TCA cycle exporting reactions. • CitPEPCK1 gene expression was activated under different conditions where inorganic nitrogen is absent. [ABSTRACT FROM AUTHOR]

The paper highlights the importance of optimal design model in the design evaluation of complex sealing mechanism. Sealing mechanism of the high-speed assembly machine is taken as the research object and construct rigid-flexible coupling dynamic equation. Dynamic characteristics of the sealing mechanism are analyzed by MATLAB. The maximum dynamic stress and reducing the acceleration of the end F are regarded as the optimization object. Cam profile curve parameter and the link cross section parameter are designed as the variables to construct the optimization design model of the whole sealing mechanism, and nonlinear constraint problem is transformed into a linear constraint problem. Based on the MATLAB genetic algorithm toolbox, the optimal design model of the sealing mechanism is solved, and the optimal result is obtained. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma is the most common histological type of primary liver cancer, which represents the second leading cause of cancer-related mortality. MiR-126 was reported to be downregulated in hepatocellular carcinoma tissues, compared with its levels in noncancerous tissues. However, baseline miR-126 expression levels in hepatitis B virus-related hepatocellular carcinoma patients who did not undergo pre-operational treatment remains unknown since hepatitis B virus infection and pre-operational transcatheter arterial chemoembolization were shown to upregulate miR-126 expression. Here, we demonstrated that miR-126 is generally downregulated in a homogeneous population of pre-operational treatment-naïve hepatitis B virus-related hepatocellular carcinoma patients (84.0%, 84/100), and its expression is significantly associated with pre-operational alpha-fetoprotein levels ( p < 0.05), microvascular invasion ( p < 0.05), tumor metastasis ( p < 0.05), as well as early recurrence (12 months after surgery; p < 0.01). Furthermore, the results of our study revealed that miR-126 is negatively correlated with ADAM9 expression in hepatitis B virus-related hepatocellular carcinoma patients. Overexpression of miR-126 was shown to attenuate ADAM9 expression in hepatocellular carcinoma cells, which subsequently inhibits cell migration and invasion in vitro. In addition, Cox proportional hazards regression model analysis showed that ADAM9 levels, tumor number, microvascular invasion, and tumor metastasis rate represent independent prognostic factors for shorter recurrence-free survival. In conclusion, we demonstrated that the loss of tumor suppressor miR-126 in hepatitis B virus-related hepatocellular carcinoma cells contributes to the development of metastases through the upregulated expression of its target gene, ADAM9. MiR-126-ADAM9 pathway-based therapeutic targeting may represent a novel approach for the inhibition of hepatitis B virus-related hepatocellular carcinoma metastases.

Gastrointestinal stromal tumors (GISTs) represent the most common mesenchymal tumors of the alimentary tract. These tumors may have different clinical and biological behaviors. Malignant forms usually spread via a hematogenous route, and lymph node metastases rarely occur. Herein, we report a patient with a jejunal GIST who developed supraclavicular lymph node metastasis. We conclude that lymphatic diffusion via the mediastinal lymphatic station to the supraclavicular lymph nodes can be a potential metastatic route for GISTs., Competing Interests: Conflict-of-interest statement: There is no conflict of interest.