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关键词： Free vibration   Buckling   Functionally graded porous beam   Numerical model   Finite element method   Functionally graded triply periodic minimal surface  

摘要： This work presents models to studies the free vibration and buckling characteristics of functionally graded porous (FGP) beam with triply periodic minimal surfaces including Primitive, Diamond, IWP, and Gyroid using Euler's beam theory. The models take into account the effect of the neutral axis dislocation during both vibration and buckling mode. The porous density is considered to be functionally graded along the vertical direction following the practical fabrication of architected structures. The effective stiffness is proposed in form of the three-degree polynomials and their coefficients are found by fitting the discrete data from three-dimensional finite element method (3D FEM) simulation of architected TPMSs with a wide range of porosity. The condition of gradient index is derived based on the power rule to make this work practical. 3D FEM simulations for FGP beam are carried out to validate against the present model in terms of natural frequency and neutral axis deviation to mid-plane with good agreements observed. It is found that three-degree polynomial is a good form to express the effective stiffness over the large range of porosity. In addition, the gradient index, beam dimension, architected material types, and base materials are found to affect significantly the free vibrational and buckling behaviors of beam.

关键词： Acidic endosome   Bafilomycin   Cadherin-related family member 3   Human airway epithelial cell   Human rhinovirus C  

摘要： Rhinovirus species C (RV-C) causes more severe asthma attacks than other rhinovirus species. However, the modulation of RV-C replication by drugs has not been well studied. Primary human nasal epithelial (HNE) cells cultured on filter membranes with air-liquid interface methods were infected with RV-C03, and the levels of RVC03 RNA collected from the airway surface liquid (ASL) of HNE cells were measured with a SYBR Green assay. Pretreatment of HNE cells with the specific vacuolar H+-ATPase inhibitor bafilomycin A1 reduced the RV-C03 RNA levels in the ASL;inflammatory cytokines, including interleukin (IL)-113, IL-6 and IL-8, in the supernatant;the mRNA expression of the RV-C receptor cadherin-related family member 3 (CDHR3) in the cells;and the number of acidic endosomes where RV-B RNA enters the cytoplasm. The levels of RV-C03 RNA in the ASL obtained from HNE cells with the CDHR3 rs6967,330 G/A genotype tended to be higher than those obtained from HNE cells with the G/G genotype. Pretreatment with the Na+/H+ exchanger inhibitor ethyl-isopropyl amiloride or either of the macrolides clarithromycin or EM900 also reduced RV-C03 RNA levels in the ASL and the number of acidic endosomes in HNE cells. In addition, significant levels of RV-A16, RV-B14 and RV-C25 RNA were detected in the ASL, and bafilomycin A1 also decreased the RV-C25 RNA levels. These findings suggest that bafilomycin A1 may reduce the release of RV-Cs and inflammatory cytokines from human airway epithelial cells. RV-Cs may be sensitive to drugs, including bafilomycin A1, that increase endosomal pH, and CDHR3 may mediate virus entry through receptor-mediated endocytosis in human airway epithelial cells.

关键词： Pectin   Cellulose   Homogalacturonan   Polysaccharides   Plant cell wall   Solid-state NMR  

摘要： Plant cell walls contain cellulose embedded in matrix polysaccharides. Understanding carbohydrate structures and interactions is critical to the production of biofuel and biomaterials using these natural resources. Here we present a solid-state NMR study of cellulose and pectin in C-13-labeled cell walls of Arabidopsis wild-type and mutant plants. Using 1D C-13 and 2D C-13-C-13 correlation experiments, we detected a highly branched arabinan structure in qua2 and tsd2 samples, two allelic mutants for a pectin methyltransferase. Both mutants show close physical association between cellulose and the backbones of pectic homogalacturonan and rhamnogalacturonanI. Relaxation and dipolar order parameters revealed enhanced microsecond dynamics due to polymer disorder in the mutants, but restricted motional amplitudes due to tighter pectin-cellulose associations. These molecular data shed light on polymer structure and packing in these two pectin mutants, helping to elucidate how pectin could influence cell wall architecture at the nanoscale, cell wall mechanics, and plant growth.

摘要： Primary bone marrow diffuse large B-cell lymphoma is an exceedingly rare form of non-Hodgkin lymphoma. It may demonstrate a leukemic presentation, and a proportion of cases have CD5 expression. The prognostic implications of this CD5-positivity remain unknown. Here, we present a 78-year-old man who presented with circulating peripheral blood lymphoma cells and a hypercellular marrow involved by diffuse large B-cell lymphoma, germinal center B-cell subtype. The patient responded favorably to six cycles of etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab (EPOCH-R) and intrathecal methotrexate. He unfortunately relapsed in several enlarged inguinal lymph nodes and succumbed to the lymphoma approximately one year after diagnosis, demonstrating the particularly aggressive clinical course of his disease.

关键词： 公路工程   沥青砼路面   水稳基层   伸缩缝  

摘要： 为探讨沥青砼路面水稳基层设置伸缩缝的要点,本文采用理论结合实践的方法,先分析了伸缩缝在沥青砼路面水稳基层中的作用,接着论述了沥青砼路面水稳基层的温度应变情况,最后提出设沥青砼路面水稳基层施工中设置伸缩缝的要点。研究结果表明,在沥青砼路面水稳基层施工中,在适当的位置设置伸缩缝,能够有效缓减热胀冷缩形成的应力变形情况,更好的保障施工质量,提升公路的耐久性和使用寿命,值得施工单位高度重视。