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Abstract As vaccine adjuvants, polyacrylate materials can induce a specific immune response in the body and have been widely studied in recent years due to their advantages, such as their safety, effectiveness, and low required dosage. In this study, a series of polyacrylates with hydrophobic physical crosslinking and chemical crosslinking were prepared using precipitation polymerization, and their structures were characterized by nuclear magnetic resonance spectroscopy and Fourier‐transform infrared spectroscopy. The optimal reaction conditions were determined according to the effect of reaction time, azodiisobutyronitrile, Span 60, allyl pentaerythritol, and octadecyl methacrylate (OMA) contents on the viscosity of the polyacrylate microgel, combined with the effects of allyl pentaerythritol and OMA contents on the subcutaneous immune safety of the polyacrylate microgel in BALB/c mice. The polyacrylate microgels with different OMA contents showed good biological safety. In addition, in vivo immunity experiments were carried out in mice to analyze the adjuvant properties of ovalbumin as a model antigen. Based on the titer results of the IgG1 and IgG2a antibodies, with 1 wt % OMA content, the polyacrylate microgel vaccine could optimally induce the body to produce an immune response type dominated by Th2‐type humoral immune response and supplemented by Th1‐type cellular immune response.

This study deals with modeling and simulation of the transient behavior of an Industrial Power Plant Gas Turbine (IPGT). The data used for model setup and validation were taken experimentally during the start-up procedure of a single-shaft heavy duty gas turbine. Two different models are developed and compared by using both a physics-based and a black-box approach, and are implemented by using the matlab© tools including Simulink and Neural Network toolbox, respectively. The Simulink model was constructed based on the thermodynamic and energy balance equations in matlab environment. The nonlinear autoregressive with exogenous inputs NARX model was set up by using the same data sets and subsequently applied to each of the data sets separately. The results showed that both Simulink and NARX models are capable of satisfactory prediction, if it is considered that the data used for model training and validation is experimental data taken during gas turbine normal operation by using its standard instrumentation. [ABSTRACT FROM AUTHOR]

Background: CD28 expression is correlated withm alignancy development in long-term survivors after liver transplantation. Immune cell activation is mediated by the interaction of CD28 with CD4 and CD8. Objectives: In this study, we attempted to investigate the expression level and prognostic value of CD28 in hepatocellular carcinoma (HCC). Methods: A total of 54HCC patients with complete clinical information were examined. The expression level of CD28 in HCC tissues was detected by immunohistochemistry. The correlations of CD28 expression with clinical characteristics, CD4+/CD8+ T-cells, and prognosis in HCC were analyzed. The expression profile of CD28 and survival time of HCC patients were retrieved from the TCGA database, followed by survival analysis. Results: The positive expression rate of CD28 in HCC tissues was 70.73%. The CD28 expression was significantly higher in the positive expression group (area: 659174.9 670060, IOD: 123348.3 106348.6) than in the negative expression group (area: 8405.7 9983.3, IOD: 1959.6 2117.7) (P < 0.01). The CD4+ and CD8+ cell counts were 526.13 258.17 cells/ L and 383.93 223.39 cells/ L, respectively. The expression level of CD28was significantly related to the degree of differentiation and the number of CD4+ and CD8+ T-cells (P < 0.05). The survival time of patients was longer in the positive CD28 expression group than in the negative expression group. Based on the CD28 expression profiles of 406 HCC patients retrieved from the TCGA database, patients with high CD28 expression showed a better prognosis than those with low expression (P < 0.05). Conclusions: CD28may play a vital role in the occurrence, development, and prognosis of HCC by interacting with CD4+ and CD8+ T-cells. Thus, CD28 could be suggested as the immune checkpoint target for HCC treatment. [ABSTRACT FROM AUTHOR]

This paper introduces the equations of motion of modular 2D snake robots moving in vertical plane employing Series Elastic Actuators (SEAs). The kinematics of such 2D modular snake robot is presented in an efficient matrix form and Euler-Lagrange equations are constructed to model the robot. Moreover, using a spring-damper contact model, external contact forces, necessary for modeling pedal wave motion (undulation in the vertical plane) are taken into account, which unlike existing methods can be used to model the effect of multiple contact points. Using such a contact model, pedal wave motion of the robot is simulated and the torque signal measured by the elastic element from the simulation and experimentation are used to show the validity of the model. Moreover, pedal wave locomotion of such robot on uneven terrain is also modeled and an adaptive controller based on torque feedback in gait parameter's space with optimized control gain is proposed. The simulation and experimentation results showed the efficacy of the proposed controller as the robot successfully climbed over a stair-type obstacle without any prior knowledge about its location with at least 24.8% higher speed compared with non-adaptive motion. [ABSTRACT FROM AUTHOR]

Eukaryotic mRNAs are appended at the 5′ end, with the 7-methylguanosine cap linked by a 5′-5′-triphosphate bridge to the first transcribed nucleoside (m7GpppX). Initiation of cap-dependent translation of mRNA requires direct interaction between the cap structure and the eukaryotic translation initiation factor eIF4E. Biophysical studies of the association between eIF4E and various cap analogs have demonstrated that m7GTP binds to the protein ca. -5.0 kcal/mol more favorably than unmethylated GTP. In this work, a thermodynamic analysis of the binding process between eIF4E and several cap analogs has been conducted using Monte Carlo (MC) simulations in conjunction with free energy perturbation (FEP) calculations. To address the role of the 7-methyl group in the eIF4E/m7GpppX cap interaction, binding free energies have been computed for m7GTP, GTP, protonated GTP at N(7), the 7-methyldeazaguanosine 5′-triphosphate (m7DTP), and 7-deazaguanosine 5′-triphosphate (DTP) cap analogs. The MC/FEP simulations for the GTP→m7DTP transformation demonstrate that half of the binding free energy gain of m7GTP with respect to GTP can be attributed to favorable van der Waals interactions with Trp166 and reduced desolvation penalty due to the N(7) methyl group. The methyl group both eliminates the desolvation penalty of the N(7) atom upon binding and creates a larger cavity within the solvent that further facilitates the desolvation step. Analysis of the pair m7GTP-m7DTP suggests that the remaining gain in affinity is related to the positive charge created on the guanine moiety due to the N(7) methylation. The charge provides favorable cation-π interactions with Trp56 and Trp102 and decreases the negative molecular charge, which helps the transfer from the solvent, a more polar environment, to the protein. [ABSTRACT FROM AUTHOR]