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BackgroundTo investigate the effect of albumin infusion in cirrhotic patients admitted for acute gastrointestinal bleeding.MethodsMedical records of cirrhotic patients who admitted due to acute gastrointestinal bleeding through January 2009 to December 2018 were systemically reviewed. Clinical data and the total amount of albumin and red blood cell used during hospitalization were recorded. For patients with rebleeding, the amount of albumin and red blood cell used before rebleeding was also documented. The primary outcome was the occurrence of rebleeding and the second outcome was in-hospital mortality. Univariate and multivariate logistic analysis were performed to identify risk factors associated with rebleeding and in-hospital mortality.ResultsA total of 2239 cirrhotic patients were included in the analysis. There were 245 episodes of in-patient rebleeding occurred, while 135 patients died. Overall, more red blood cells and albumin were prescribed to patients who suffered rebleeding. In terms of the amount before rebleeding, the red blood cell was higher in patients with rebleeding, but the albumin infusion were similar. In the multivariate model, the albumin infusion was an independent risk factor associated with rebleeding (adjusted OR for ≤40g, 0.385 [0.252-0.588], p40g, 0.295 [0.169-0.514], p40g, 0.389 [0.180-0.838], p=0.016).ConclusionsAlbumin infusion could reduce risk of in-hospital rebleeding. Moreover, more than 40g albumin infusion decrease numbers of mortality in cirrhosis admitted for acute gastrointestinal bleeding.

Background To investigate the effect of albumin infusion on cirrhotic patients admitted for acute gastrointestinal bleeding. Methods Medical records of cirrhotic patients who admitted due to acute gastrointestinal bleeding through January 2009 to December 2018 were reviewed. Clinical data and the total amount of albumin and red blood cell used during hospitalization were recorded. For patients with rebleeding, the amount of albumin and red blood cell used before rebleeding was also documented. The primary outcome was the occurrence of rebleeding, and the second outcome was in-hospital mortality. Univariate and multivariate logistic analysis was performed to identify risk factors associated with rebleeding and in-hospital mortality. Results A total of 1503 cirrhotic patients were included in the analysis. There were 146 episodes of in-patient rebleeding occurred, while 81 patients died. Overall, more red blood cells and albumin were prescribed to patients who suffered rebleeding. In terms of the amount before rebleeding, the red blood cell was higher in patients with rebleeding, but the albumin infusion was similar. In the multivariate model, the albumin infusion before rebleeding was an independent risk factor associated with rebleeding (adjusted OR for ≤40 g vs 0 g, 0.469 [0.269–0.793], p = 0.006; adjusted OR for > 40 g vs 0 g, 0.272 [0.115–0.576], p = 0.001). In Child-Pugh C class patients, the use of albumin more than 40 g during hospitalization associated with a lower risk of in-patient mortality (adjusted OR for > 40 g vs 0 g, 0.136 [0.019–0.741], p = 0.031). Conclusions Albumin infusion was associated with a lower risk of rebleeding and in-hospital deaths in cirrhosis admitted for acute gastrointestinal bleeding.

The hot deformation behaviors of Cr5 steel were investigated. The hot compression tests were conducted in the temperature range of 900−1150 °C under strain rates of 0.01, 0.1 and 1 s−1. The constitutive equation and material constants (Q, n, α lnA) are obtained according to the hyperbolic sine function and Zener-Hollomon parameter. Besides, dynamic recrystallization (DRX) grain size model and critical strain model are acquired. The processing maps with the strain of 0.1, 0.3 and 0.5 are obtained on the basis of dynamic materials model. It has been observed that DRX occurs at high temperature and low strain rate. According to the processing map, the safety region exists in the temperature range of 920−1150 °C with strain rate of 0.01−0.20 s−1.

The dynamic recrystallization behavior of high strength steel during hot deformation was investigated. The hot compression test was conducted in the temperature range of 950-1150 °C under strain rates of 0.1, 1 and 5 s-1. It is observed that dynamic recrystallization (DRX) is the main flow softening mechanism and the flow stress increases with decreasing temperature and increasing strain rate. The relationship between material constants (Q, n, α and lnA) and strain is identified by the sixth order polynomial fit. The constitutive model is developed to predict the flow stress of the material incorporating the strain softening effect and verified. Moreover, the critical characteristics of DRX are extracted from the stress-strain curves under different deformation conditions by linear regression. The dynamic recrystallization volume fraction decreases with increasing strain rate at a constant temperature or decreasing deformation temperature under a constant strain rate. The kinetics of DRX increases with increasing deformation temperature or strain rate.

Concentration of 4 heavy metals (Cu, Pb, Zn, Cd) and petroleum hydrocarbon in the surface sediments collected from Chenglingji, Dongting Lake, were quantitatively analyzed. Distribution characteristics and possible sources of the heavy metals and petroleum hydrocarbon were discussed. Methods of single-factor index and geoaccumulation index were adopted to evaluate the potential ecological risks of heavy metal. The results showed that Cd was seriously polluted and in a strong ecological risk level; Cu, Pb and Zn pollution was mild in Chenglingji Port, Dongting Lake. Petroleum hydrocarbon content of nearshore sediment was low exclude of area near Chenglingji Port, which significantly exceeded the standard value. And the content of petroleum hydrocarbon decreased with the distance far away from the harbor.

The variation of microstructure of Ti-IF steel of extra deep drawing grade, which having a 83%cold-rolled deformation under simulated batch annealing process at temperature ranging from 480°C to 750°C, was studied by using optical microscopy, X-ray diffraction (XRD) and metallographic micro-hardness tester. The evolution of texture during the recrystallization process was analyzed by Orientation Density Function (ODF). The results show that, the recrystallization temperature of experimental steel is 620-630°C, and the recrystallization process can be accomplished within 1h at660°C. Four major textures after cold rolling are observed as follows,{001}, {111}, {111} and {112}, respectively. At the early stage of recrystallization annealing, texture evolves from {111} toγ-{111}, which is quite beneficial to achieve high deep drawing performance,the texture {001} and {112} change marginally. as the annealing temperature rises up to 720°C, texture {001} and {112} change into fiber textureγ-{111}. After annealing,{111} and {111} textures become the two main types.

Based on hot metal pretreatment (HMPT)-basic oxygen furnace (BOF)-Rheinstahl Heraeus (RH)-compact strip production (CSP) process, parameters controlling on cold rolling deep drawing substrate SPHE were investigated during smelting and rolling process by composition design and technology control. The influence of parameters on chemical compositions, mechanical properties and microstructure was revealed by scanning electron microscope (SEM). The results show that, 1) main chemical components in SPHE are w(C)≤40×10−6, w(Si)≤ 0.01%, w(S)≤0.009%, w(N)≤20×10−6, w(O)≤ 25×10−6; 2) main mechanical properties of the SPHE are σs=274 MPa, σb=334 MPa, A=48.9%; 3) main performances of deep drawing quality (DDQ) grade steel produced by SPHE are as follows, transversely σs=167 MPa, σb=298 MPa, n=0.219, r=2.46; vertically σs=166 MPa, σb=298 MPa, n=0.226, r=2.39; in 45° direction σs=171 MPa, σb=308 MPa, n=0.214, r=2.26; 4) microstructure of DDQ is ferrite, average grain size is Grade 7.5, and inclusion size is 3–10 μm.

Although mesenchymal stem cells (MSCs) have been increasingly trialed to treat a variety of diseases, the underlying mechanisms remain still elusive. In this study, human umbilical cord (UC)-derived MSCs were stimulated by hypoxia, and the membrane microvesicles (MVs) in the supernatants were collected by ultracentrifugation, observed under an electron microscope, and the origin was identified with the flow cytometric technique. The results showed that upon hypoxic stimulus, MSCs released a large quantity of MVs of ∼100 nm in diameter. The MVs were phenotypically similar to the parent MSCs, except that the majority of them were negative for the receptor of platelet-derived growth factor. DiI-labeling assay revealed that MSC-MVs could be internalized into human UC endothelial cells (UC-ECs) within 8 h after they were added into the culture medium. Carboxyfluorescein succinimidyl ester-labeling technique and MTT test showed that MSC-MVs promoted the proliferation of UC-ECs in a dose-dependent manner. Further, MVs could enhance in vitro capillary network formation of UC-ECs in a Matrigel matrix. In a rat hindlimb ischemia model, both MSCs and MSC-MVs were shown to improve significantly the blood flow recovery compared with the control medium (P

An adaptive genetic algorithm was proposed to optimization bound in order to speed up the convergence of Gaussian mean shift. In practical question, as it's difficult to give a critical value definitely. According to the engine nonlinear of the corresponding oil and performance parameters, in gradient genetic algorithm, BP algorithm of local search is introduced. The adaptive value of chromosomes group gets quickly improved with the search in one coding field getting avoided due to the utilization of knowledge of chromosomes in problem-domain. The crossover and mutation operations are added so that chromosomes will not fall into the local minimum point in neighborhood. The experimental results prove that the convergence speed of the proposed method is non-linear and the use of gradient genetic algorithm is a fast algorithm that can support the global optimization of chromosomes in a group of process of iteration.

Oxidation Kinetics of SPHC was analyzed by TGA, and the curve of oxidation weight gain with different temperature was acquired. It is found that, when the oxidation temperature is between 500°C and 600°C, all the curves are linear; when the oxidation temperature is above 700°C, the curves are close to parabolic. At the temperature of 900°C, the oxidation weight gain increases dramatically. The TGA results indicate that the activation energy of SPHC steel is 146.19 kJ/mol at the temperature of 500°C~900°C, and an oxidation kinetic model was set up for variable temperature. Based on the temperature change during rolling process, numerical simulation of oxide scales evolution was carried out for SPHC steel, and the simulation result agreed well with measured ones. It can provide a basis for estimating the scale growth and controlling the temperature on site.

High temperature mechanical properties of 50Cr5MoV roll steel was investigated by Gleeble 1500 thermal simulator testing machine. The morphology, composition and microstructure of fracture surface were observed and analyzed by OM, SEM and EDS. The results are indicative of that, there are two brittle temperature zones of 50Cr5MoV roll steel at the temperature of 600°C~950°Cand 1300°C~1450°C, respectively. The section shrinkage rate is less than 60%. The fracture mode changes from mixed ones dominated by intergranular to toughness transgranular one with the increase of temperature at the range of 650”C~1300°C. The fracture is along the solid--liquid phase at the range of 1300°C~melting point. It is crucial to formulate the 50Cr5MoV casting technology, to prevent the cracks and improve the quality of 50Cr5MoV roll steel.