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Open access

Ye-Feng Lu, Yan Wang, Ming-Zhu Huang, Xue-Fei Ren, Lei-Qing Gao, Dan Li, Yan-Fen Li and Yan Yang

Abstract

Objective

There is little information focusing on the nutritional issue of pediatric recipients before they receive living donor liver transplantation. This study illustrates the relationship between nutritional status and graft liver function and provides a reference regarding nutritional interventions in future studies.

Methods

We prospectively collected data from 30 pediatric living donor liver transplant recipients from January 1, 2016, to June 30, 2016. The information included demographic data, preoperative nutritional assessment, and postoperative laboratory examinations. The nutritional assessment included the serum concentration of vitamin D, bone density, trace element, and weight Z value. The laboratory examinations included white blood cell count, neutrophil percentage, hemoglobin, blood platelet, total protein, albumin, total bilirubin, direct bilirubin, alanine transaminase, aspartate aminotransferase (AST), alkaline phosphatase, gamma-glutamyl transpeptidase, creatinine, bile acid, blood glucose (Glu), prothrombin time, international normalized ratio, tacrolimus concentration, and graft-to-recipient weight ratio (GRWR). The data were collected on Days 1, 2, 3, 4, 5, 6, 7, 14, 30, and 60 after liver transplantation.

Results

The recipients consisted of 15 (50%) males and 15 (50%) females. The median age was 7 months (4–48 months). The mean height and weight were 69.07±9.98 cm and 8.09±2.63 kg, respectively. According to the univariate analysis, the gender, diagnosis, blood type, and GRWR did not significantly impact the liver function after the operation. The posttransplantation AST levels and Glu showed significant differences in terms of the nutritional status, with P<0.05. The multivariate correlation analysis showed that the serum concentrations of vitamin D and AST were midrange positively correlated, with P<0.05.

Conclusions

The nutritional status of patients with biliary atresia is relatively poor. There is a definite midrange positive correlation between nutrition and graft liver function that might play a relatively important role in the recovery of the graft.

Open access

Hui Yang, Yan Zhao, Min Li and Falin Wu

Abstract

To reduce the influence of the static unbalance on an infrared missile guidance system, a new static unbalance measure system for the gimbals axes has been developed. Considering the coupling effects caused by a mass eccentricity, the static balance condition and measure sequence for each gimbal axis are obtained. A novel static unbalance test approach is proposed after analyzing the dynamic model of the measured gimbal axis. This approach is to drive the measured gimbal axis to do sinusoidal reciprocating motion in a small angle and collect its drive currents in real time. Then the static unbalance of the measured gimbal axis can be obtained by the current multi-cycle integration. Also a measuring system using the proposed approach has been developed. A balanced simulator is used to verify the proposed approach by the load and repeatability tests. The results show the proposed approach enhances the efficiency of the static unbalance measurement, and the developed measuring system is able to achieve a high precision with a greater stability.

Open access

Lu Qingzhen, Yin Yuanchao, Yang Zhixun, Chen Jinlong, Yan Jun and Yue Qianjin

Abstract

The fatigue problem induced by wave loads and floater movements of dynamic umbilicals in deepwater is studied. The prediction method of the fatigue life is investigated by considering no-linear local stress due to contact and friction between components of the umbilical. A case study of a dynamic umbilical for 1500 meters depth in South China Sea was presented. The results showed that the more accurate result of the fatigue life was calculated by considering non-linear local stress. The fatigue life by considering local stress with the no-slip assumption was conservative. An obviously longer fatigue life was obtained by considering local stress with the full-slip assumption.

Open access

Qian Wang, Xiaomei Yang, Xiao Yan and Kaiyu Qin

Abstract

Based on real-time multi-domain communication signal analysis architecture, a high-efficiency blind carrier frequency estimation algorithm using the power spectrum symmetry of the measured modulated signal is presented. The proposed algorithm, which utilizes the moving averaged power spectrum achieved by the realtime spectrum analysis, iteratively identifies the carrier frequency in according to the power difference between the upper sideband and lower sideband, which is defined and revised by the estimated carrier frequency in each iteration. When the power difference of the two sidebands converges to the preset threshold, the carrier frequency can be obtained. For the modulation analysis, the measured signal can be coarsely compensated by the estimated result, and the residual carrier frequency error is eliminated by a following carrier synchronization loop. Compared with previous works, owing to the moving averaged power spectrum normalization and the smart iterative step variation mechanism for the two sidebands definition, the carrier frequency estimation accuracy and speed can be significantly improved without increasing the computational effort. Experimental results are included to demonstrate the outstanding performance of the proposed algorithm.

Open access

Xuesong Fu, Yan Yang, QuanYang Ma, Xiaodong Peng and Tiancai Xu

Abstract

Mg-0.5Si-xSn (x=0.95, 2.9, 5.02wt.%) alloys were cast and extruded at 593K (320 oC) with an extrusion ratio of 25. The microstructure and mechanical properties of as-cast and extruded test alloys were investigated by OM, SEM, XRD and tensile tests. The experimental results indicate that the microstructure of the Mg-0.5Si-xSn alloys consists of primary α-Mg dendrites and an interdendritic eutectic containing α-Mg, Mg2Si and Mg2Sn. There is no coarse primary Mg2Si phase in the test alloys due to low Si content. With the increase in the Sn content, the Mg2Si phase was refined. The shape of Mg2Si phase was changed from branch to short bar, and the size of them were reduced. The ultimate tensile strength and yield strength of Mg-0.52Si-2.9Sn alloy at the temperature of 473K (200 oC) reach 133MPa and 112MPa respectively. Refined eutectic Mg2Si phase and dispersed Mg2Sn phase with good elevated temperature stability are beneficial to improve the elevated temperature performance of the alloys. However, with the excess addition of Sn, large block-like Mg2Sn appears around the grain boundary leading to lower mechanical properties.

Open access

Yan Yang and Yichao Chen

Abstract

The thickness of a graph is the minimum number of planar spanning subgraphs into which the graph can be decomposed. It is a measurement of the closeness to the planarity of a graph, and it also has important applications to VLSI design, but it has been known for only few graphs. We obtain the thickness of vertex-amalgamation and bar-amalgamation of graphs, the lower and upper bounds for the thickness of edge-amalgamation and 2-vertex-amalgamation of graphs, respectively. We also study the thickness of Cartesian product of graphs, and by using operations on graphs, we derive the thickness of the Cartesian product KnPm for most values of m and n.

Open access

Guodong Zha, Bochu Wang, Junyu Liu, Jie Yan, Liqing Zhu and Xingyan Yang

Abstract

The gravity-induced mechanical touch stimulus can affect plant root architecture. Mechanical touch responses of plant roots are an important aspect of plant root growth and development. Previous studies have reported that Arabidopsis TCH1-3 genes are involved in mechano-related events, how-ever, the physiological functions of TCH1-3 genes in Arabidopsis root mechanoresponses remain unclear. In the present study, we applied an inclined hard agar plate method to produce mechanical touch stimulus, and provided evidence that altered mechanical environment could influence root growth. Furthermore, tch1-3 Arabidopsis mutants were investigated on inclined agar surfaces to explore the functions of TCH1-3 genes on Arabidopsis root mechanoresponses. The results showed that two tch2 mutants, cml24-2 and cml24-4, exhibited significantly reduced root length, biased skewing, and decreased density of lateral root. In addition, primary root length and density of lateral root of tch3 (cml12-2) was significantly decreased on inclined agar surfaces. This study indicates that the tch2 and tch3 mutants are hypersensitive to mechanical touch stimulus, and TCH2 (CML24-2 and CML24-4) and TCH3 (CML12-2) genes may participate in the mechanical touch response of Arabidopsis roots.

Open access

Li-Feng Yang, Jing-Ying Liu and Yan-Hui Liu

Abstract

Objective

The aim of this study was to explore whether positive emotion mediates the relationship between job burnout and turnover intentions among Chinese nurses.

Methods

A cross-sectional survey was conducted in the present study. Full-time registered nurses (n = 150) from Grade A hospitals in Tianjin were surveyed. Pearson correlation, hierarchical regression analyses, and the Sobel test were used in the study.

Results

The results illustrated that positive emotion mediated the relationship between burnout and nurses’ turnover intention.

Conclusions

Nursing administrators should pay more attention to the benefits of positive emotions on working motivation. It is helpful to relieve burnout in the working process so that nurses are willing to remain in their current employment.

Open access

Hongfeng Lv, Weiping Yan, Xiaobo Yang, Jiechao Li and Jieying Zhu

A kind of multi-channel capillary electrophoresis (CE) chip signal detection system based on CCD was developed. The output signal of the CCD sensor was processed by a series of pre-processing circuits and ADC, and then it was collected by the Field Programmable Gate Array (FPGA) chip which communicated with a host computer. The core in FPGA was designed to control the signal flow of the CCD and transfer the data to PC based on a Nios II embedded soft-processor. The application of PC was used to store the data and demonstrate the curve. The measurement of the fluorescent signals for different concentration Rhodamine B dyes is presented and the comparison with other detection systems is also discussed.