Evaluation of nano-frictional and mechanical properties of a novel Langmuir-Blodgett monolayer/self-assembly monolayer composite structure

A novel stearic acid (SA)/3-aminopropyltrethoxysilane (APS) composite structure was fabricated using the combined method of the Langmuir-Blodgett technique and self-assembly monolayer (SAM) technique. Its frictional, adhesive properties and interface contact types between the atomic force microscope tip and the samples were evaluated based on Amonton's laws and the general Carpick's transition equation, respectively. The results showed that the tip-sample contacts corresponded to the Johnson-Kendall-Robert/Derjaguin-Muller-Toporov (DMT) transition model for SiO2, APS-SAMs, and the unheated SA-APS composite structure, and for the heated SA-APS bilayer to the DMT model. Frictional forces for the four samples were linearly dependent on external loads at higher loads, and at lower loads they were significantly affected by adhesive forces. Frictional and scratching tests showed that the heated SA-APS composite structure exhibited the best lubricating properties and adhesion resistance ability, and its wear resistance capacity was greatly improved due to the binding-mode conversion from hydrogen bonds to covalent bonds. Thus, this kind of composite bilayer might be promising for applications in the lubrication of nano/microelectromechanical systems. I.Comment: 8 pages, 8 figure

The effect of modified observation-teaching-discussion pedagogy combined with microteaching on the critical thinking ability of nursing interns in China: a quasi-experimental study

AimThe aim of this study is to investigate the effect of modified observation-teaching-discussion pedagogy combined with microteaching on improving the critical thinking ability of nursing interns in China.MethodsTwo hundred baccalaureate nursing students practicing in the department of neurosurgery were divided into two groups chronologically, with 100 students per group. The control group received traditional clinical mentoring while their counterparts in the intervention group received mentoring by modified observation teaching discussion pedagogy combined with microteaching. Then, we compared the two groups with respect to theoretical knowledge and nursing operation skills. The Critical Thinking Ability Scale was used to evaluate the critical thinking ability of the two groups of nursing students. Data were analyzed with SPSS 22.0 software.ResultsFollowing the internship, the scores of nurses in the intervention group were significantly higher than those in the control group for theoretical knowledge, technical skills and critical thinking ability (p < 0.05 for all).ConclusionThe application of modified observation-teaching-discussion pedagogy in combination with microteaching promoted the knowledge, technical skills and critical thinking ability of nursing students in clinical practice

A Role for Phosphodiesterase 3B in Acquisition of Brown Fat Characteristics by White Adipose Tissue in Male Mice.

Obesity is linked to various diseases, including insulin resistance, diabetes, and cardiovascular disorders. The idea of inducing white adipose tissue (WAT) to assume characteristics of brown adipose tissue (BAT), and thus gearing it to fat-burning instead of storage, is receiving serious consideration as potential treatment for obesity and related disorders. Phosphodiesterase 3B (PDE3B) links insulin- and cAMP-signaling networks in tissues associated with energy metabolism, including WAT. We utilized C57BL/6 PDE3B knockout (KO) mice to elucidate mechanisms involved in the formation of BAT in epididymal WAT (EWAT) depots. Examination of gene expression profiles in PDE3B KO EWAT revealed increased expression of several genes that block white and promote brown adipogenesis, such as C-terminal binding protein (Ctbp), bone morphogenetic protein 7 (Bmp7) and PR domain containing 16 (Prdm16), but a clear BAT-like phenotype was not completely induced. However, acute treatment of PDE3B KO mice with the β3-adrenergic agonist, CL316243, markedly increased expression of cyclooxygenase-2 (COX-2), which catalyzes prostaglandin synthesis and is thought to be important in formation of BAT in WAT, and of elongation of very long chain fatty acids 3 (Elovl3), which is linked to BAT recruitment upon cold exposure, causing a clear shift toward fat-burning and induction of BAT in KO EWAT. These data provide insight into mechanisms of BAT formation in mouse EWAT, suggesting that, in C57BL/6 background, an increase in cAMP, caused by ablation of PDE3B and administration of CL316243, may promote differentiation of prostaglandin-responsive progenitor cells in the EWAT stromal vascular fraction into functional brown adipocytes

Inhibition of NOX1 mitigates blood pressure increases in elastin insufficiency

Elastin (ELN) insufficiency leads to the cardiovascular hallmarks of the contiguous gene deletion disorder, Williams-Beuren syndrome, including hypertension and vascular stiffness. Previous studies showed that Williams-Beuren syndrome deletions, which extended to include th

Berry Curvature and Bulk-Boundary Correspondence from Transport Measurement for Photonic Chern Bands

Berry curvature is a fundamental element to characterize topological quantum physics, while a full measurement of Berry curvature in momentum space was not reported for topological states. Here we achieve two-dimensional Berry curvature reconstruction in a photonic quantum anomalous Hall system via Hall transport measurement of a momentum-resolved wave packet. Integrating measured Berry curvature over the two-dimensional Brillouin zone, we obtain Chern numbers corresponding to -1 and 0. Further, we identify bulk-boundary correspondence by measuring topology-linked chiral edge states at the boundary. The full topological characterization of photonic Chern bands from Berry curvature, Chern number, and edge transport measurements enables our photonic system to serve as a versatile platform for further in-depth study of novel topological physics