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Separation of hydrogen isotopes (D2/H2) attracts wide interest due to its important applications, such as nuclear fusion. Kinetic quantum sieving‐induced separation over tailored nanoporous solids is a promising method; however, the dynamic separation often shows a transient feature, thus a low D2/H2 selectivity even at temperature below 50 K. Herein, we selectively enriched the accessible quantum sieving (AQS) sites in two‐dimensional carbons by chemically growing a pore‐narrowing layer. The spatial density of such AQS sites is 8.5 times higher than that of commercial carbon molecular sieves. The kinetic selectivity of D2/H2 reached 4.6 at 77 K. Column breakthrough experiments revealed that the dynamic D2/H2 separation was enhanced by such a nanopore design. Aspen simulation indicated that D2 was enriched to 93.1% within 11 pressure swing adsorption cycles with a 1% D2/99% H2 mixture as feed. [ABSTRACT FROM AUTHOR]

Objective: Explore an accurate transosseous tunnel drilling method based on three‐dimensional (3D) printing technology for acromioclavicular joint reconstruction (ACD), design a guide design, and evaluate its accuracy. Methods: Using Mimics software to reconstruct 100 cases of acromioclavicular joint computed tomography (CT) data. In design 2, the non‐collinear tunnel is superimposed on the 3D model, and a virtual drilling is performed between the clavicle and the coracoid using a triple inner gusset. Then, in the Geomagic Studio software model, an elliptical plane is calculated and extracted as a guide design for precise drilling. Then put the design and the 3D shoulder model together for 3D printing. Ten lengths were measured, and the effects of the virtual model, the actual model, and the guide rail design were compared. Results: We successfully compared 10 parameters of 3D virtual model and actual model. There was no significant difference between actual and virtual bone tunnels in 10 measurements (P > 0.05). Conclusions: The accuracy of ACD combined with 3D printing guidance design technology in the transosseous tunnel of adult shoulder is reliable. [ABSTRACT FROM AUTHOR]

Recently, novel core–shell MOF@COF hybrids display excellent performance in various fields because of their inherited advantages from their parent MOFs and/or COFs. However, it is still a grand challenge to adjust the morphology of MOFs and/or COFs for consequent performance improvement. Herein, a Ti‐MOF@TpTt hybrid coated with ultra‐thin COF nanobelt, which is different from the fibrillar‐like parent COF, is successfully synthesized through a sequential growth strategy. The as‐obtained Pd decorated Ti‐MOF@TpTt catalyst exhibits much higher photocatalytic performance than those of Ti‐MOF, TpTt‐COF, and Ti‐MOF@TpTt hybrids with fibrillar‐like COF shell for the photocatalytic cascade reactions of ammonia borane (AB) hydrolysis and nitroarenes hydrogenation. These can be attributed to its high BET surface area, core–shell structure, and type II heterojunction, which offers more accessible active sites and improves the separation efficiency of photo‐generated carriers. Finally, the possible mechanisms of the cascade reaction are also proposed to well explain the improved performance of this photocatalytic system. This work presents a constructive route for designing core–shell MOF@COF hybrids with controllable morphology adjustment of COF shell, leading to the improved photocatalytic ability to broaden the applications of MOF/COF hybrid materials. [ABSTRACT FROM AUTHOR]

Bicyclo[1.1.0]butanes (BCBs) are highly strained carbocycles that have emerged as versatile synthetic tools, particularly for the construction of functionalized small molecules. This work reports two efficient pathways for the rapid preparation of over 20 structurally diverse BCB ketones, encompassing simple alkyl and aryl derivatives, as well as unprecedented amino acid, dipeptide, bioisostere, and bifunctional linchpin reagents currently inaccessible using literature methods. Analogues are readily forged in two steps and in high yields from simple carboxylic acids or through unsymmetrical ketone synthesis beginning with a convenient carbonyl dication equivalent. The utility of this novel toolbox of strained electrophiles for the selective modification of proteinogenic nucleophiles is highlighted. [ABSTRACT FROM AUTHOR]

By making use of the host-guest interactions between the host molecule tris- o-phenylenedioxycyclotriphosphazene (TPP) and the rod-coil block copolymer (BCP) poly(ethylene oxide)- block-poly(octyl 4′-octyloxy-2-vinylbiphenyl-4-carboxylate) (PEO- b-PVBP), the supramolecular rod-rod block copolymer P(EO@TPP)- b-PVBP was constructed. It consists of a crystalline segment P(EO@TPP) with a hexagonal crystalline structure and a columnar nematic liquid-crystalline segment (PVBP). As the PVBP segments arrange themselves as columnar nematic phases, the crystalline structure of the inclusion complex P(EO@TPP), which has a smaller diameter, is destroyed. The self-assembled nanostructure is thus clearly affected by the interplay between the two blocks. On the basis of wide- and small-angle X-ray scattering analysis, we conclude that the supramolecular rod-rod BCP can self-assemble into a cylinder-in-cylinder double hexagonal structure. [ABSTRACT FROM AUTHOR]

Five different kinds of monofunctionalized hexa- peri-hexabenzocoronenes (HBCs) are synthesized by loading dialkyl-diphenylacetylenes and asymmetric diphenylacetylene derivatives at the same time. This method shortens the synthetic route by half, with four fewer steps compared with the commonly used approach. In addition, this method is more economic and environmentally friendly. The self-assembling properties of the molecules are greatly influenced by the substituted alkyl side chains. From the short linear hexyl chain (C6) to the longer n-dodecyl (C12) chain and then to the branched alkyl chain (C10,6), the transition temperature from the crystalline phase to the liquid crystalline (LC) phase and that from the LC phase to the isotropic (Iso) state both decrease. Furthermore, the ester group far away from the aromatic core and its length are also important variables to control the phase behaviors of the molecules. The typical long-range ordered hexagonal lattice (Colh phase) is found for all the monofunctionalized molecules in their LC states. [ABSTRACT FROM AUTHOR]

Resistance to trastuzumab and concomitantly distal metastasis are leading causes of mortality in HER2-positive breast cancers, the molecular basis of which remains largely unknown. Here, we generated trastuzumab-resistant breast cancer cells with increased tumorigenicity and invasiveness compared with parental cells, and observed robust epithelial-mesenchymal transition (EMT) and consistently elevated TGF-β signaling in these cells. MiR-200c, which was the most significantly downregulated miRNA in trastuzumab-resistant cells, restored trastuzumab sensitivity and suppressed invasion of breast cancer cells by concurrently targeting ZNF217, a transcriptional activator of TGF-β, and ZEB1, a known mediator of TGF-β signaling. Given the reported backward inhibition of miR-200c by ZEB1, ZNF217 also exerts a feedback suppression of miR-200c via TGF-β/ZEB1 signaling. Restoration of miR-200c, silencing of ZEB1 or ZNF217 or blockade of TGF-β signaling increased trastuzumab sensitivity and suppressed invasiveness of breast cancer cells. Therefore, our study unraveled nested regulatory circuits of miR-200c/ZEB1 and miR-200c/ZNF217/TGF-β/ZEB1 in synergistically promoting trastuzumab resistance and metastasis of breast cancer cells. These findings provide novel insights into the common role of EMT and related molecular machinery in mediating the malignant phenotypes of breast cancers. [ABSTRACT FROM AUTHOR]

In the title compound, C(19)H(19)NO(13), one of the two fused furan-ose rings adopts an envelope conformation whereas the other displays a twisted conformation. The crystal structure is stabilized by inter-molecular C-H⋯π inter-actions between a methine H atom and the triacetoxy-phenyl ring of an adjacent mol-ecule, and by weak non-classical inter-molecular C-H⋯O hydrogen bonds.