•Superplasticity of TiAl alloy sheet with bimodal grain size distribution at the lowest temperature of 800 ℃ is realised.•Maximum elongation of ~360% is obtained at 900 ℃ with an initial strain rate ...of 2.0 × 10-4 s-1.•In-situ XRD verifies that there is no order-disorder transformation of β phase during superplastic deformation.•The coordination of dynamic recrystallization and grain-boundary sliding is the main mechanism of superplastic behaviour.
The superplasticity of Ti-43Al-9V-0.2Y alloy sheet hot-rolled at 1100 °C was systematically investigated in the temperature range of 750−900 °C under an initial strain rate of 10−4 s−1. A bimodal γ grain-distribution microstructure of TiAl alloy sheet, with abundant nano-scale or sub-micron γ laths embedded inside β matrix, exhibits an impressive superplastic behaviour. This inhomogeneous microstructure shows low-temperature superplasticity with a strain-rate sensitivity exponent of m = 0.27 at 800 °C, which is the lowest temperature of superplastic deformation for TiAl alloys attained so far. The maximum elongation reaches ~360% at 900 °C with an initial strain rate of 2.0 × 10−4 s−1. To elucidate the softening mechanism of the disordered β phase during superplastic deformation, the changes of phase composition were investigated up to 1000 °C using in situ high-temperature X-ray diffraction (XRD) in this study. The results indicate that β phase does not undergo the transformation from an ordered L20 structure to a disordered A2 structure and cannot coordinate superplastic deformation as a lubricant. Based on the microstructural evolution and occurrence of both γ and β dynamic recrystallization (DR) after tensile tests as characterized with electron backscatter diffraction (EBSD), the superplastic deformation mechanism can be explained by the combination of DR and grain boundary slipping (GBS). In the early stage of superplastic deformation, DR is an important coordination mechanism as associated with the reduced cavitation and dislocation density with increasing tensile temperature. Sufficient DR can relieve stress concentration arising from dislocation piling-up at grain boundaries through the fragmentation from the original coarse structures into the fine equiaxed ones due to recrystallization, which further effectively suppresses apparent grain growth during superplastic deformation. At the late stage of superplastic deformation, these equiaxed grains make GBS prevalent, which can effectively avoid intergranular cracking and is conducive to the further improvement in elongation. This study advances the understanding of the superplastic deformation mechanism of intermetallic TiAl alloy.
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Objective
To explore the impact of ferritin level on the disassociation of glycated hemoglobin A1c (HbA1c) and mean plasma glucose (MPG).
Reseach Design and Methods
We used a 2012‐2013 ...cross‐sectional survey conducted in Pinggu district, Beijing including 3095 Chinese participants aged 25‐75 years. We categorized their glycemic status by interviewing for diagnosed diabetes and by measuring HbA1c, fasting plasma glucose (FPG), and 2‐hours post‐load plasma glucose (2‐hours PPG). We fitted a multivariable regression model to explore the impact of ferritin on the association of HbA1c or glycated albumin (GA) and mean plasma glucose.
Results
A total of 5.65% of participants were diagnosed as diabetes using HbA1c criteria, and 9.79% using oral glucose tolerance test criteria. Compared with males, females had significantly lower hemoglobin levels (159.82 ± 11.56 vs 135.93 ± 12.62) and lower ferritin levels (113.00 68.55, 185.50 vs 33.40 12.40, 70.13). Linear regression analysis performed in different groups classified by different diagnose criterion indicated that the correlation between MPG and HbA1c differs in different tertiles of ferritin (lowest vs middle vs highest: R2 = 0.507 vs 0.645 vs 0.687 in female; R2 = 0.415 vs 0.715 vs 0.615 in male), and the association between MPG and HbA1c diminished in the lowest tertile of ferritin.
Conclusions
Ferritin level might affect the association between glucose and HbA1c, which should be taken into account when using HbA1c as a diagnosis criterion for diabetes and prediabetes.
摘要
目的
探讨铁蛋白水平如何影响糖化血红蛋白(HbA1c)与平均血糖的关系
研究设计与方法
我们使用了2012‐2013年在北京市平谷区进行的横断面调查; 这项调查纳入了3095名年龄在25‐75岁的中国受试者。根据了解既往确诊糖尿病史和测量HbA1c、空腹血糖与负荷后两小时血糖对受试者的血糖状况进行分类。通过拟合的多变量回顾模型; 分析铁蛋白水平如何影响平均血糖与HbA1c、糖化白蛋白的关系。
结果
根据HbA1c标准; 共有5.65%的受试者被诊断为糖尿病; 而根据口服糖耐量试验标准则有9.79%被诊断为糖尿病。相比于男性; 女性受试者的血红蛋白水平显著更低(159.82±11.56 vs. 135.93±12.62 g/L); 铁蛋白水平也更低(113.00 68.55, 185.50 vs. 33.40 μg/L 12.40, 70.13)。在根据不同诊断标准划分的不同组别中进行的线性回归显示; 平均血糖值和HbA1c之间的相关性在铁蛋白值三分位组中有所不同(最低、中间与最高:女性R2 = 0.507 vs 0.645 vs 0.687； 男性R2 = 0.415 vs 0.715 vs 0.615)。平均血糖值和HbA1c之间的相关性在铁蛋白最低三分位组中最低。
结论
铁蛋白水平可能会影响血糖与HbA1c之间的相关性; 在将HbA1c用作糖尿病和糖尿病前期的诊断标准时应予以考虑。
Highlights
The current study demonstrated that ferritin level could affect the relationship between HbA1c and mean plasma glucose.
Prevalence rate of diabetes based on HbA1c is lower than that of glucose‐based diabetes, which is true across all ferritin levels.
The design of a vehicle suspension, which is truly a multi-degree of freedom mechanism, is really challenging. This paper primarily focuses on Kinematics and Dynamic analysis of the system in ADAMS. ...A specific module of chassis platform is developed to analyze suspension ride comfort on adaptability to different vehicle with ADAMS/Car. The work intention is to make a parametric ADAMS model and then link it to a Knowledge Based Engineering application to facilitate designer to quickly carry out designing iterations in order to reduce development time. The Knowledge Based Engineering software is made using object oriented language called ‘Object Definition Language’ which is developed using VC++ software languages. The module not only carry through parametric modeling of front and rear suspension and other subsystems of chassis quickly and compactly, but also can carry on the analysis and optimization of various factors those have crucial impact on ride comfort. The module offers two test-bend, vehicle virtual simulation test stand and four-post test rig. Finally, the module is applied to analyze two kinds of cars which used chassis platform: front and rear frequency determination, pulse inspiration simulation and Broad simulation. The results show that the chassis platform being adopted by two kinds of cars meet the ride comfort requirements.
Duret hemorrhage after lumbar drainage Yuan, Xunhui; Zhao, Hongyan; Zhao, Cuiling ...
The Journal of craniofacial surgery,
07/2014, Letnik:
25, Številka:
4
Journal Article
Recenzirano
Lumbar drainage (LD) is considered as a simple and effective procedure for the treatment of intracerebral hemorrhage with ventricular involvement. However, cerebrospinal fluid overdrainage and ...hypovolemia due to LD could induce severe fatal complications, which include transtentorial herniation and infratentorial hemorrhage. Here, we describe a 63-year-old man with transtentorial herniations and Duret hemorrhage attributable to LD after the operation of thalamic hematoma removal. This is probably the first reported case of severe complications of LD. Thus, complications related to transtentorial herniations and Duret hemorrhage should be kept in mind while performing LD.
A novel type of carboxylated multiwalled carbon nanotube modified electrode（c-MWCNTs/GCE） was constructed and the electrochemical properties of phenacetin（PHE） at it were studied. In a buffer ...solution of 0.1 mol/L HAc-NaAc（pH=5.3）, PHE exhibited a couple of quasi-reversible redox peaks and an anodic peak in the poten- tial range of 0.2--1.2 V at c-MWCNTs/GCE. The peak current was proportional to the concentration of PHE in the range of 4.0× 10^-6_ 1.0 × 10^-4 mol/L with a detection limit of 1.0× 10^-6 mol/L（S/N=3）. The c-MWCNTs/GCE showed excellent repeatability and stability and the electrochemical reaction mechanism of PHE was proposed. This method was used to determine the content of PHE in medical tablets and the recovery was determined to be 96.5%--104.2% by means of a standard addition method.
Fibroblast growth factor receptor 3 (FGFR3), highly conserved in both humans and murine, is one of key tyrosine kinase receptors for FGF. FGFR3 is expressed in different tissues, including cartilage, ...brain, kidney, and intestine at different development stages. Conventional knockout of Fgfr3 alleles leads to short life span, and overgrowth of bone. In clinic, human FGFR3 mutations are responsible for three different types of chondrodysplasia syndromes including achondroplasia (ACH), hypochondroplasia (HCH) and thanatophoric dysplasia (TD). For better understanding of the roles of FGFR3 in different tissues at different stages of development and in pathological conditions, we generated Fgfr3 conditional knockout mice in which loxp sites flank exons 9-10 in the Fgfr3 allele. We also demonstrated that Cre-mediated recombination using Col2a1-Cre, a Cre line expressed in chondrocyte during bone development, results in specific deletion of the gene in tissues containing cartilage. This animal model will be useful to study distinct roles of FGFR3 in different tissues at different ages.
Based on the person-organization fit theory, this research aims to investigate how socially responsible HRM (SRHRM) positively affects employees’ organizational citizenship behaviors toward the ...environment (OCBE) by increasing person-organization fit. This study also captures the moderating effect of the perceived role of ethics and social responsibility (RESR) in influencing the indirect effect of SRHRM on OCBE via person-organization fit. Data were collected from 302 employees in a state-owned chain hotel in Shanghai, China. The results indicated that SRHRM indirectly influenced employee’s engagement in OCBE through person-organization fit. The positive relationship between SRHRM and person-organization fit and the indirect effect of SRHRM on OCBE via person-organization fit were more significant when employees hold high rather than low levels of RESR. Research implications and prospects were also explored in this study.
In the present study, hygroscopicity of the choline chloride-urea (ChCl-2Urea) ionic liquid (IL) was confirmed through Karl-Fisher titration examination, indicating that the water content in the ...hydrated ChCl-2Urea IL was exposure-time dependent and could be tailored by simple heating treatment. The impact of the absorbed water on the properties of ChCl-2Urea IL, including viscosity, electrical conductivity, electrochemical window and chemical structure was investigated. The results show that water was able to dramatically reduce the viscosity and improve the conductivity, however, a broad electrochemical window could be persisted when the water content was below ~6 wt.%. These characteristics were beneficial for producing dense and compact coatings. Nickel (Ni) coatings plating from hydrated ChCl-2Urea IL, which was selected as an example to show the effect of water on the electroplating, displayed that a compact and corrosion-resistant Ni coating was plated from ChCl-2Urea IL containing 6 wt.% water doped with 400 mg/L NA at a moderate temperature. As verified by FTIR analysis, the intrinsic reason could be ascribed that water was likely linked with urea through strong hydrogen bond so that the water decomposition was suppressed during plating. Present study may provide a reference to prepare some similar water-stable ILs for plating.
In this work, we find that the peroxidase-like activity of MoS2 nanoparticles (NPs) is dependent on the surface charge. Negatively charged sodium dodecyl sulfate modified MoS2 nanoparticles (SDS–MoS2 ...NPs) possess highly-efficient peroxidase-like activity. MoS2 NPs with intrinsic peroxidase-like activity were synthesized through a simple one-pot hydrothermal route. The peroxidase-like activities of different surfactants modified MoS2 NPs were discussed. Compared with bare MoS2 NPs and positively charged cetyltrimethyl ammonium bromide modified MoS2 NPs, SDS–MoS2 NPs have the best peroxidase-like activity. SDS–MoS2 NPs can efficiently catalyze the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of H2O2 to generate a blue product. On basis of this, we have successfully established a novel platform for colorimetric detection of H2O2, and the detection limit is 0.32μM. Furthermore, the SDS–MoS2 NPs based platform can also be used for high sensitivity and selectivity detection of glucose with a wide linear range of 5.0–500μM by controlling the generation of H2O2 in the presence of glucose oxidase.
Sodium dodecyl sulphate modified MoS2 nanoparticles show highly-efficient peroxidase-like activity and can be used for the colorimetric detection of H2O2 and glucose. Display omitted
•Surface charge could affect the peroxidase-like activity of MoS2 NPs.•SDS–MoS2 NPs possess highly-efficient peroxidase-like activity.•Catalytic kinetics of SDS–MoS2 NPs show a ping–pong mechanism.•Colorimetric detection of H2O2 and glucose was realized.
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