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Generally, the potential reactive "olefin pairs" in the molecular crystals satisfying Schmidt's criteria could undergo topological [2+2] cycloaddition. In this study, another factor that affects the photodimerization reactivity of chalcone analogues was found. The cyclic chalcone analogues of (E)‐2‐(2,4‐dichlorobenzylidene)‐2,3‐dihydro‐1H‐inden‐1‐one (BIO), (E)‐2‐(naphthalen‐2‐ylmethylene)‐2,3‐dihydro‐1H‐inden‐1‐one (NIO), (Z)‐2‐(2,4‐dichlorobenzylidene)benzofuran‐3(2H)‐one (BFO), and (Z)‐2‐(2,4‐dichlorobenzylidene)benzo[b]thiophen‐3(2H)‐one (BTO) have been synthesized. While the geometrical parameters for the molecular packing of the above four compounds did not exceed Schmidt's criteria, [2+2] cycloaddition did not occur in the crystals of BIO and BTO. The single crystal structures and Hirshfeld surface analyses revealed that interactions of C=O⋅⋅⋅H (CH2) existed between adjacent molecules in the crystal of BIO. Therefore, the carbonyl and methylene groups linked with one carbon atom in carbon‐carbon double bond were tightly confined in the lattice, acting as a tweezer to inhibit free movement of the double bond and suppressing [2+2] cycloaddition. In the crystal of BTO, similar interactions of Cl⋅⋅⋅S and C=O⋅⋅⋅H (C6H4) prevented free movement of the double bond. In contrast, the intermolecular interaction of C=O⋅⋅⋅H only exists around the carbonyl group in the crystals of BFO and NIO, leaving the C=C double bonds to move freely and allowing the occurrence of [2+2] cycloaddition. Driven by photodimerization, the needle‐like crystals of BFO and NIO displayed evident photo‐induced bending behavior. This work demonstrates that the intermolecular interactions around carbon‐carbon double bond affect the [2+2] cycloaddition reactivity except for Schmidt's criteria. These findings provide valuable insights into the design of photomechanical molecular crystalline materials. [ABSTRACT FROM AUTHOR]

Developing an efficient catalyst for formic acid (FA) dehydrogenation is a promising strategy for safe hydrogen storage and transportation. Herein, we successfully developed trimetallic NiAuPd heterogeneous catalysts through a galvanic replacement reaction and a subsequent chemical reduction process to boost hydrogen generation from FA decomposition at room temperature by coupling Fermi level engineering with plasmonic effect. We demonstrated that Ni worked as an electron reservoir to donate electrons to Au and Pd driven by Fermi level equilibrium whereas plasmonic Au served as an optical absorber to generate energetic hot electrons and a charge‐redistribution mediator. Ni and Au worked cooperatively to promote the charge heterogeneity of surface‐active Pd sites, leading to enhanced chemisorption of formate‐related intermediates and eventually outstanding activity (342 mmol g−1 h−1) compared with bimetallic counterpart. This work offers excellent insight into the rational design of efficient catalysts for practical hydrogen energy exploitation. [ABSTRACT FROM AUTHOR]

Evaluating the therapeutic response and survival of lung cancer patients receiving first‐line chemotherapy has always been difficult. Limited biomarkers for evaluation exist and as a result histology represents an empiric tool to guide therapeutic decision making. In this study, molecular signatures associated with response and long‐term survival of lung cancer patients receiving first‐line chemotherapy are discovered. Whole‐exome sequencing is performed on pretherapeutic tissue samples of 186 patients [145 non‐small cell lung cancer (NSCLC) and 41 small cell lung cancer (SCLC)]. On the basis of genomic alteration characteristics, NSCLC patients can be classified into four subtypes (C1–C4). The long‐term survival is similar among different subtypes. SCLC patients are also divided into four subtypes and significant difference in their progression free survival is revealed (P < 0.001). NSCLC patients can be divided into three subtypes (S1–S3) based on TMB. A trend of worse survival associated with higher TMB in subtype S3 than in S1+S2 is found. In contrast, no significant correlations between molecular subtype and therapeutic response are observed. In conclusion, this study identifies several molecular signatures associated with response and survival to first‐line chemotherapy in lung cancer. [ABSTRACT FROM AUTHOR]

The microstructures and optical properties of Ce,Mg:Lu3Al5O12 scintillator ceramics are investigated with particular focus on the effect of postannealing in air from 1000 to 1450°C. The formation of Al2O3 clusters after annealing above 1300°C is evidenced by scanning electron microscopy. The presence of this secondary phase is tentatively explained by the occurrence of Ce and Mg evaporation, proved by inductive coupled plasma optical emission spectrometry measurements, followed by defect diffusion and clustering during high temperature annealing. Meanwhile, optical investigations including absorption, X‐ray induced luminescence, light yield, scintillation decay, and thermoluminescence prove the positive role of post‐annealing that leads to a brighter and faster scintillation emission. This behavior is associated to the removal of oxygen vacancies occurring during such treatments. In parallel, the partial conversion of Ce3+ ions into Ce4+ is also observed as a consequence of annealings and the role of Ce4+ ions in the scintillation process is discussed. [ABSTRACT FROM AUTHOR]