Hysteresis behavior of reinforced concrete bridge piers considering strength and stiffness degradation and pinching effect

In order to effectively simulate the nonlinear hysteresis behavior of reinforced concrete (RC) bridge piers under strong earthquake excitation, an improved nonlinear hysteresis model for RC bridge piers was developed and its controlling parameters were determined considering stiffness and strength degradation and pinching effect based on classical Bouc-Wen model. The improved model can be carried out to predict the nonlinear hysteresis behavior of RC bridge piers under various failure modes using MATLAB/ Simulink program. Cyclic tests of different failure mode bridge column specimens were performed under constant axial load with lateral bending. The results did show that force-displacement relationship curves of bridge column specimens derived from theoretical analysis agree well with experimental results. The nonlinear hysteresis behavior of bridge column specimen was simulated under 2008 Wenchuan earthquake excitation and its failure modes were identical with real earthquake damage of bridge column. The improved analytical models in the paper were applied to accurately predicting the nonlinear hysteresis behavior of RC bridge columns with strength and stiffness degradations and the pinching effect subjected to strong earthquake motion

Research on the impact of entrepreneurial learning on business model design under the moderation of information cocoons

Entrepreneurial learning plays a significant role in promoting business model design． In the information age everyone will fall into the information cocoon effect． Will the information cocoons have an impact on entrepreneurs’ business model design decisions? Based on the cognitive perspective of business model research starting from the two entrepreneurial learning levels of individual learning and organizational learning this study constructs a logical relationship model that drives the business model design of start-ups through entrepreneurial learning． At the same time it is also taken into consideration that the phenomenon of information cocoons in the mass media environment exists in this process and has an impact on the business model design outcome． Through a questionnaire survey and empirical analysis of 322 entrepreneurs the research finds that in the process of entrepreneurship organizational learning matches the design of novelty-centered business models; information cocoons objectively exist in the process of business model design driven by entrepreneurial learning and it, to a certain extent limits the innovative behavior of entrepreneurs

Granulocyte colony-stimulating factor affects the distribution and clonality of TRGV and TRDV repertoire of T cells and graft-versus-host disease

<p>Abstract</p> <p>Background</p> <p>The immune modulatory effect of granulocyte colony-stimulating factor (G-CSF) on T cells resulted in an unexpected low incidence of graft-versus-host disease (GVHD) in allogeneic peripheral blood stem cell transplantation (allo-PBSCT). Recent data indicated that gamma delta⁺T cells might participate in mediating graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effect after allogeneic hematopoietic stem cell transplantation. However, whether G-CSF could influence the T cell receptors (TCR) of gamma delta⁺T cells (<it>TRGV </it>and <it>TRDV </it>repertoire) remains unclear. To further characterize this feature, we compared the distribution and clonality of <it>TRGV </it>and <it>TRDV </it>repertoire of T cells before and after G-CSF mobilization and investigated the association between the changes of TCR repertoire and GVHD in patients undergoing G-CSF mobilized allo-PBSCT.</p> <p>Methods</p> <p>The complementarity-determining region 3 (CDR3) sizes of three <it>TRGV </it>and eight <it>TRDV </it>subfamily genes were analyzed in peripheral blood mononuclear cells (PBMCs) from 20 donors before and after G-CSF mobilization, using RT-PCR and genescan technique. To determine the expression levels of <it>TRGV </it>subfamily genes, we performed quantitative analysis of <it>TRGV</it>I~III subfamilies by real-time PCR.</p> <p>Results</p> <p>The expression levels of three <it>TRGV </it>subfamilies were significantly decreased after G-CSF mobilization (<it>P </it>= 0.015, 0.009 and 0.006, respectively). The pattern of <it>TRGV </it>subfamily expression levels was <it>TRGV</it>II ><it>TRGV </it>I ><it>TRGV </it>III before mobilization, and changed to <it>TRGV </it>I ><it>TRGV </it>II ><it>TRGV </it>III after G-CSF mobilization. The expression frequencies of <it>TRGV </it>and <it>TRDV </it>subfamilies changed at different levels after G-CSF mobilization. Most <it>TRGV </it>and <it>TRDV </it>subfamilies revealed polyclonality from pre-G-CSF-mobilized and G-CSF-mobilized samples. Oligoclonality was detected in <it>TRGV </it>and <it>TRDV </it>subfamilies in 3 donors before mobilization and in another 4 donors after G-CSF mobilization, distributed in <it>TRGV</it>II, <it>TRDV</it>1, <it>TRDV</it>3 and <it>TRDV</it>6, respectively. Significant positive association was observed between the invariable clonality of <it>TRDV</it>1 gene repertoire after G-CSF mobilization and low incidence of GVHD in recipients (<it>P </it>= 0.015, <it>OR </it>= 0.047).</p> <p>Conclusions</p> <p>G-CSF mobilization not only influences the distribution and expression levels of <it>TRGV </it>and <it>TRDV </it>repertoire, but also changes the clonality of gamma delta⁺T cells. This alteration of <it>TRGV </it>and <it>TRDV </it>repertoire might play a role in mediating GVHD in G-CSF mobilized allo-PBSCT.</p

SATB2 shows different profiles between appendiceal adenocarcinomas ex goblet cell carcinoids and appendiceal/colorectal conventional adenocarcinomas: An immunohistochemical study with comparison to CDX2

Background: Special AT-rich sequence-binding protein 2 (SATB2) is a novel marker for colorectal adenocarcinomas but little is known about its expression in appendiceal adenocarcinomas. We aim to investigate SATB2 in these tumors and colorectal adenocarcinomas with comparison to CDX2. Methods: Immunohistochemical stains for SATB2 and CDX2 were performed in 49 appendiceal adenocarcinomas (23 conventional, 26 adenocarcinoma ex goblet cell carcinoids (AdexGCCs)) and 57 colorectal adenocarcinomas. Their expression was correlated with tumor differentiation and growth patterns. Results: SATB2 staining was positive in 26/26 (100%) appendiceal AdexGCCs and 15/23 (65%) appendiceal conventional adenocarcinomas (P = 0.001). Their mean percentage of SATB2-positive cells was 93% and 34%, respectively (P \u3c 0.0001). CDX2 staining was seen in 26/26 (100%) AdexGCCs and 22/23 (96%) appendiceal conventional adenocarcinomas (P = 0.4694). SATB2 and CDX2 showed similar staining in AdexGCCs but CDX2 labeled more tumor cells than SATB2 in conventional adenocarcinomas (mean 84% vs. 34%, P \u3c 0.0001). SATB2 and CDX2 staining was seen in 82% (47/57) and 96% (55/57) colorectal adenocarcinomas, respectively (P = 0.01). The mean percentage of cells positive for SATB2 and CDX2 was 48% and 91%, respectively (P \u3c 0.00001). Decreased SATB2 immunoreactivity was associated with non-glandular differentiation particularly signet ring cells in colorectal (P = 0.001) and appendiceal conventional adenocarcinomas (P = 0.04) but not in appendiceal AdexGCCs. Conclusions: SATB2 is a highly sensitive marker for appendiceal AdexGCCs with similar sensitivity as CDX2. In colorectal and appendiceal conventional adenocarcinomas, SATB2 is not as sensitive as CDX2 and its immunoreactivity is dependent on tumor differentiation

Plasma-enabled catalytic steam reforming of toluene as a biomass tar surrogate: Understanding the synergistic effect of plasma catalysis

In this study, steam reforming of toluene was carried out in a dielectric barrier discharge (DBD) plasma reactor combined with Ni/γ-Al2O3 catalysts. The effect of reaction temperature, calcination temperature of catalysts, and relative permittivity of packing materials, on the reaction performance and synergistic effect of plasma catalysis was investigated. The results showed that toluene conversion decreased initially and then increased with increasing temperature, due to a decreasing average reduced electric field and increasing catalytic activity at higher temperatures. At 450 °C, the process achieved a high toluene conversion of 87.1%, a total gas yield of 72.6%, and an energy efficiency of 18.2 g/kWh, demonstrating the potential of this approach for sustainable hydrogen production. Catalysts prepared at lower calcination temperatures or with higher relative permittivity packing materials perform better, owing to the larger Ni surface area available for catalytic reactions and the higher surface discharge facilitating the occurrence of surface reactions. In addition, the synergistic capacity in terms of toluene conversion and gas production exhibited a positive relationship with the metal surface area of catalysts and the relative permittivity of packing materials, while the relationship between reaction temperature and toluene conversion was negative