BIM技术在国际铁路建设项目管理中的应用推广演化博弈研究

BIM技术的应用可有效提高国际铁路建设项目的效益。通过构建业主、承包商双方演化博弈模型,研究双方BIM技术推广与应用行为演化机理、探究双方达到最优稳定状态的条件,并通过仿真模拟研究双方的演化路径和影响系统演化的因素。结果表明,推广与使用成本、激励与补贴、声誉收益与损失等因素影响双方的行为选择。最终,根据研究结果对业主与承包商提出了相应建议。

Sequential reactant water management by complementary multisite catalysts for surpassing platinum hydrogen evolution activity

Alkaline hydrogen evolution reaction(HER)offers a near-zero-emission approach to advance hydrogen energy.However,the activity limited by the multiple reaction steps involving H_(2)O molecules transfer,absorption,and activation still unqualified the thresholds of economic viability.Herein,we proposed a multisite complementary strategy that incorporates hydrophilic Mo and electrophilic V into Ni-based catalysts to divide the distinct steps on atomically dispersive sites and thus realize sequential regulation of the HER process.The Isotopic labeled in situ Raman spectroscopy describes 4-coordinated hydrogen bonded H_(2)O to be free H_(2)O passing the inner Helmholtz plane in the vicinity of the catalysts under the action of hydrophilic Mo sites.Furthermore,potential-dependent electrochemical impedance spectroscopy(EIS)reveals that electrophilic V sites with abundant 3d empty orbitals could activate the lone-pair electrons in the free H_(2)O molecules to produce more protic hydrogen,and dimerize into H_(2) at the Ni sites.By the sequential management of reactive H_(2)O molecules,NiMoV oxides multisite catalysts surpass Pt/C hydrogen evolution activity(49 mV@10 mA∙cm^(-2) over 140 h).Profoundly,this study provides a tangible model to deepen the comprehension of the catalyst–electrolyte interface and create efficient catalysts for diverse reactions.

TMEM181:a key mediator of cytolethal distending toxin required for Wnt signaling activity

Wnt signaling pathway plays critical roles in a variety of embryonic developmental processes and also controls homeostatic selfrenewal in a number of adult tissues(Flaherty and Dawn,2008;Nusse and Clevers,2017).At the cell membrane,Wnt ligands bind to the seven transmembrane receptors of Frizzled family and the co-receptors to activate intracellular signaling pathway,including theβ-catenin-dependent canonical Wnt signaling pathway,the noncanonical planar cell polarity(PCP)pathway and the Wnt/calcium pathway(Flaherty and Dawn,2008).In mammals,WNT4,WNT5A.

Essential role of Msx1 in regulating anterior-posterior patterning of the secondary palate in mice

Development of the secondary palate displays molecular heterogeneity along the anterior-posterior axis;however, the underlying molecular mechanism remains largely unknown. MSX1 is an anteriorly expressed transcription repressor required for palate development. Here, we investigate the role of Msx1 in regional patterning of the secondary palate. The Wnt1-Cre-mediated expression of Msx1(Rosa Msx1^(Wnt1-Cre))throughout the palatal mesenchyme leads to cleft palate in mice, associated with aberrant cell proliferation and cell death. Osteogenic patterning of the hard palate in Rosa Msx1^(Wnt1-Cre)mice is severely impaired, as revealed by a marked reduction in palatine bone formation and decreased expression of the osteogenic regulator Sp7. Overexpression and knockout of Msx1 in mice show that the transcription repressor promotes the expression of the anterior palate-specific Alx1 but represses the expression of the medialposterior palate genes Barx1, Meox2, and Tbx22. Furthermore, Tbx22 constitutes a direct Msx1 target gene in the secondary palate, suggesting that Msx1 can directly repress the expression of medial-posterior specific genes. Finally, we determine that Sp7 is downstream of Tbx22 in palatal mesenchymal cells,suggesting that a Msx1/Tbx22/Sp7 axis participates in the regulation of palate development. Our findings unveil a novel role for Msx1 in regulating the anterior-posterior growth and patterning of the secondary palate.

Coordinatively unsaturated cobalt single-atom nanozymes for visual pesticides detection by smartphone-based platform

By adjusting the coordination environment of single-atom catalysts,the enzyme-like activity can be finely tuned for highly sensitive biosensing.Herein,we demonstrated that coordinatively unsaturated cobalt-nitrogen sites doped within porous carbon(SA-CoN_(3))could serve as highly efficient oxidase mimic.Compared with the typical planar four-coordination structure(SA-CoN_(4)),the as-obtained single-atom Co nanozymes anchored by three nitrogen atoms are found to display much higher oxidase-like catalytic efficiency.Combined theoretical and experimental analysis revealed that the coordinatively unsaturated Co sites could facilitate adsorption and activation of O_(2) molecule and thus improve their oxidase-like activity.Based on the enhanced oxidase-like activity of SA-CoN_(3),a paper/smartphone sensor for organophosphorus pesticides(OPs)was successfully constructed and used to quantify glyphosate in environmental and food samples with a low detection limit of 0.66μM.This work not only highlights the important role of coordination unsaturation of SA nanozymes for promoting oxidase-like activity,but also provides an easy and cost-effective way to conduct effective quantification of OPs in the field.