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The water-soluble substances in Goji was extracted by aqueous extraction method. Using half maximal inhibitory concentration (IC50) value of scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals as response value, the extraction process was optimized by response surface tests on the basis of single factor tests. The water-soluble antioxidant components in Goji were analyzed by ultra performance liquid chromatography coupled with quadrupole-time of flight-mass spectrometry (UPLC-QTOF-MS). The results showed that the optimal extraction conditions were as follows: solid-liquid ratio 1∶180 (g∶ml), extraction temperature 80 ℃ and time 2 h. The IC50 value of scavenging DPPH radicals of the extracting solution was 1.34 g/L under these optimized conditions. The analysis by UPLC-QTOF-MS indicated that a total of 6 substances capable of scavenging DPPH radicals were detected in the aqueous extracting solution of Goji, which were beriberic acid, betaine, kaempferol-3-O-sophorodisaccharide-7-O-glucoside, proline, L-arginine and rutin, respectively.

Abstract Background To show the femoral neck better in hip lateral view of X-ray, we design a modified hip lateral view and then investigate the value in femoral neck fractures. Methods CT images of 10 normal hip joints for 3D reconstruction were selected, the Mimics Medical 21.0 was used, and rotating the proximal femur was to find the most suitable angle for showing the femoral neck well, designed the modified lateral view according to this angle. We collected 35 healthy cases and 35 femoral neck fractures as the normal and fracture group. And two groups were all taken hip anteroposterior view, cross-table lateral view and modified lateral view, which were analyzed by two radiologists to score the anatomical structures of the articular surface, femoral head, head neck junction, femoral neck, basal region and intertrochanteric region. Friedman test was used to analyze the score of femoral neck at different angles. T test and Wilcoxon signed-rank test were to compare inter-groups. Results The modified lateral view was designed as follows: The subjects were supine, with the sagittal axis biased toward the healthy side at an angle of approximately 20° to the long axis of the examination table, the hip joint flexed at 45°, the lower extremity abducted at 40°, the centerline inclined 45° toward the head and the centerline aligned with the center of the groin. The modified lateral view showed the femoral head, head neck junction and femoral neck more clearly than the cross-table lateral view, but the cross-table lateral view showed the femoral neck basal and intertrochanteric region better. In addition, the time of taking the modified lateral view was significantly less than the cross-table lateral view (normal group: 0.789 min ± 0.223 vs 0.623 min ± 0.207, P

PURPOSEWe aimed to establish a liver function evaluation model by combining multiparametric magnetic resonance imaging (MRI) with liver volume (LV) and further verify the effectiveness of the model to evaluate liver function.METHODSThis retrospective study included 101 consecutive cirrhosis patients (69 cases for modeling group and 32 cases for validation group) who underwent gadoxetic acid-enhanced MRI. Five signal intensity parameters were obtained by measuring the signal intensities of the liver, spleen, and erector spinae before and 20 minutes after gadoxetic acid disodium enhancement. The diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) were obtained from intravoxel incoherent motion diffusion-weighted imaging. The LV parameters (Vliver, Vspleen, and Vliver/Vspleen) were obtained using 3-dimensional image generation software. The most effective parameter was selected from each of the 3 methods, and a multivariate regression model for liver function evaluation was established and validated.RESULTSIn the modeling group, relative enhancement (RE), D*, and Vliver/Vspleen showed significant differences among the different liver function groups (P < .001). Receiver operating characteristic analysis showed that these parameters had the highest area under the curve (AUC) values for distinguishing Child-Pugh A from Child-Pugh B and C groups (0.917, 0.929, and 0.885, respectively). The following liver function model was obtained by multivariate regression analysis: F(x)=3.96 − 1.243 (RE) − 0.034 (D*) − 0.080 (Vliver/Vspleen) (R2=0.811, P < .001). In the patients with cirrhosis, the F(x) of Child-Pugh A, B, and C were 1.16 ± 0.44, 1.95 ± 0.29, and 2.79 ± 0.38, respectively. In the validation group, the AUC for F(x) to distinguish Child-Pugh A from Child-Pugh B and C was 0.973.CONCLUSIONCombining multiparametric MRI with LV effectively distinguished patients with different ChildPugh grades. This model could hence be useful as a novel radiological marker to estimate the liver function.

In the present paper, the mooring system of an offshore aquaculture platform is designed and optimized, applying a shallow water mooring system design methodology which combines the Non-dominated Sorting Genetic Algorithm-II (NSGA-II) and the cable–platform coupled model. One mooring design is first given using the proposed methodology. Two reference mooring systems are modified based on an NSGA-II design, and AIP criteria and expertise. The hydrodynamic performance of the offshore aquaculture platform with these three mooring systems is compared via use of a potential flow time–domain numerical simulation. A physical model-scale experiment is carried out to validate the numerical coupled model. Both numerical and experimental results confirm the effectiveness of present model. The comparative analysis shows that the mooring system designed using NSGA-II can provide a relative radical solution compared to the other two mooring designs when considering a limited budget.

The present work presents numerical research on the wake flows behind a propeller operating under three advance coefficients. Large eddy simulations are adopted to obtain the viscous flow information behind the propeller. In particular, the study highlights the comparison of the evolution characteristics and the flow physics within the propeller wakes with three advance coefficients. The predicted global force and moment coefficients and phase-average statistics of streamwise velocity agree well with the available experimental data. Compared to all other flow structures in the wake, the tip vortices are found to play the most significant role according to the results. During the pairing process of adjacent tip vortices, the tip vortices diffuse circumferentially, leading to enhanced mutual-induction effects. When the advance coefficient is low, the wake becomes distorted, and the pairing process takes place in the middle region of the flow field. As a result of their unstable motion, the four tip vortices generated by the propeller cannot be distinguished individually in the far field. Instead, they break down into smaller vortices and tend to distribute themselves uniformly in the azimuthal direction. The increase in the advance coefficient delays the pairing process. This study offers valuable insights for the design and optimization of marine propellers.

Soil acidification often occurs when the concentration of ammonium (NH4+) in soil rises, such as that observed in farmland. Both soil acidification and excess NH4+ have serious adverse effects on crop growth and food production. However, we still do not know which of these two inhibitors has a greater impact on the growth of crops, and the degree of their inhibitory effect on crop growth have not been accurately evaluated. 31 wheat cultivars originating in various areas of China were planted under 5 mM sole NH4+ (ammonium nitrogen, AN) or nitrate nitrogen in combined with two pH levels resembling acidified conditions (5.0 and 6.5). The results showed that the shoots and roots biomass were severely reduced by AN in both and these reduction effects were strengthened by a low medium pH. The concentration of free NH4+ and amino acids, the glutamine synthetase activity were significantly higher, but the total soluble sugar content was reduced under NH4+ conditions, and the glutamine synthetase activity was reduced by a low medium pH. Cultivar variance was responsible for the largest proportion of the total variance in plant dry weight, leaf area, nodal root number, total root length and root volume; the nitrogen (N) form explains most of the variation in N and C metabolism; the effects of pH were the greatest for plant height and root average diameter. So, soil acidification and excess NH4+ would cause different degrees of inhibition effects on different plant tissues. The findings are expected to be useful for applying effective strategies for reducing NH4+ stress in the field.

This study aims at developing a framework for assessing and tracking structural conditions by combining computer vision-based three-dimensional (3D) reconstruction and vibration measurement. Starting from a finite element (FE) model with unknown geometric and material properties, the framework seeks to obtain the accurate representation of the structure by applying a sequence of two types of operations: (1) image collection, 3D reconstruction, and the extraction of localized geometric properties, and (2) vibration measurement, operational modal analysis, and extraction of global stiffness properties. The first step, termed the computer vision step, is based on the alignment of the approximate initial finite element model to the 3D reconstruction, from which the area and second moment of area associated with each element of the model are retrieved by slicing the reconstructed mesh. The second step, termed the vibration measurement step, performs system identification using vibration measurement data, followed by the Bayesian model updating to calibrate the element stiffness. Every time one of those operations is performed, the new information is merged into all the information obtained previously. The framework is validated using a laboratory-scale bamboo cantilever beam. The experimental validation showed the potential of the proposed framework for effectively assessing and tracking localized structural conditions by heterogeneous sources of information.

Propeller wake fields in an open-water configuration were compared between two loading circumstances using large-eddy simulation (LES) with a computational domain of 48 million grids and an overset mesh technique. To validate the results of the numerical simulation, available experimental data are compared, which indicates that the grid systems are suitable for the present study. The results indicate that the present LES simulations describe the inertial frequency range well for both high and low-loading conditions. Under high-loading conditions, the interlaced spirals and secondary vortices that connect adjacent tip vortices amplify the effects of mutual inductance, ultimately triggering the breakdown of the propeller wake systems. At a great distance from the propeller, the vortex system loses all coherence and turns into a collection of smaller vortices that are equally scattered across the wake. In contrast, under light-loading conditions, the wake vortex system exhibits strong coherence and has a relatively simple topology. The elliptic instability and pairing processes are only observed at a far distance from the propeller. The convection velocity transferring tip vortices downstream is larger under the light-loading condition, which leads to the larger pitch of the helicoidal vortices. The larger pitch weakens the mutual inductance or interaction effects among tip vortices, which delays the instability behaviors of the whole vortex system. The results and implications of this study serve as a guide for the development and improvement of next-generation propellers that function optimally when operating behind aquaculture vessels.

Soil acidification often occurs when the concentration of ammonium (NH4+) in soil rises, such as that observed in farmland. Both soil acidification and excess NH4+ have serious adverse effects on crop growth and food production. However, we still do not know which of these two inhibitors has a greater impact on the growth of crops, and the degree of their inhibitory effect on crop growth have not been accurately evaluated. 31 wheat cultivars originating in various areas of China were planted under 5 mM sole NH4+ (ammonium nitrogen, AN) or nitrate nitrogen in combined with two pH levels resembling acidified conditions (5.0 and 6.5). The results showed that the shoots and roots biomass were severely reduced by AN in both and these reduction effects were strengthened by a low medium pH. The concentration of free NH4+ and amino acids, the glutamine synthetase activity were significantly higher, but the total soluble sugar content was reduced under NH4+ conditions, and the glutamine synthetase activity was reduced by a low medium pH. Cultivar variance was responsible for the largest proportion of the total variance in plant dry weight, leaf area, nodal root number, total root length and root volume; the nitrogen (N) form explains most of the variation in N and C metabolism; the effects of pH were the greatest for plant height and root average diameter. So, soil acidification and excess NH4+ would cause different degrees of inhibition effects on different plant tissues. The findings are expected to be useful for applying effective strategies for reducing NH4+ stress in the field. [ABSTRACT FROM AUTHOR]

Two novel routes to synthesize C1 nitrogen iminocyclitol structures starting from D-mannosamine hydrochloride and a modification of fructose's microbial oxidation product are proposed. High-throughput screening of the generated libraries with human N-acetyl-beta-hexosaminidases produced only moderate inhibitory activities.

Objectives: To reveal the change of renal cortical blood perfusion in primary glomerular disease (PGD) and renal aging by flow-sensitive alternating inversion recovery (FAIR) arterial spin labeling (ASL) technique. Patients and Methods: Renal cortical perfusion was estimated in 24 PGD patients and 30 healthy volunteers using FAIR-ASL in this case-control study. MRI examination was repeated after one week in six randomly selected healthy volunteers. In PGD patients, we regard estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m² as mild PGD and eGFR < 60 mL/min/1.73 m² as moderate-late PGD. The correlations between ASL perfusion values and eGFR in healthy volunteers, mild and moderate-late PGD patients were assessed. Results: In healthy volunteers, the perfusion values between the twice ASL scanning with one week-interval showed an excellent agreement by Bland-Altman analysis. The mean perfusion value of the bilateral kidneys decreased with age increase (25 - 72 years) (r = -0.496, P = 0.012). There were significant differences in ASL perfusion values among healthy volunteers, mild and moderate-late PGD patients (P < 0.0001). Perfusion values correlated strongly with eGFR in all PGD patients (r = 0.868, P < 0.0001), but not in healthy volunteers (r = 0.156, P = 0.405). The correlation coefficient of perfusion values with eGFR in mild and moderate-late PGD patients were 0.749 (P = 0.008) and 0.809 (P = 0.010), respectively. Conclusion: FAIR-ASL technique represents a feasible approach to monitor the renal perfusion variations in PGD patients. It is a noninvasive technique to discover the early abnormality of renal function, and assess the degree of renal aging. [ABSTRACT FROM AUTHOR]

A versatile chemical approach for displaying target compounds on the bacterial cell wall is described. Such a method allows a large variety of molecular specimens to be displayed thus leading to a wide range of applications such as in the discovery of novel drugs/vaccines utilizing lactic acid bacteria.