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The introduction of K+ into a RbNa3(Li3SiO4)4:Eu2+ phosphor to partially or completely replace Rb+ allows the emission spectrum to be modulated from blue (λ = 473 nm, FWHM = 22.5 nm) to a narrow cyan band (λ = 485 nm, FWHM = 21.1 nm).

Advances in (spectroscopic) characterization of the unusual electronic structures of open-shell cobalt complexes bearing redox-active ligands, combined with detailed mapping of their reactivity, have uncovered several new catalytic radical-type protocols that make efficient use of the synergistic properties of redox-active ligands, redox-active substrates, and the metal to which they coordinate. In this perspective, we discuss the tools available to study, induce, and control catalytic radical-type reactions with redox-active ligands and/or substrates, contemplating recent developments in the field, including some noteworthy tools, methods, and reactions developed in our own group. The main topics covered are (i) tools to characterize redox-active ligands; (ii) novel synthetic applications of catalytic reactions that make use of redox-active carbene and nitrene substrates at open-shell cobalt-porphyrins; (iii) development of catalytic reactions that take advantage of purely ligand- and substrate-based redox processes, coupled to cobalt-centered spin-changing events in a synergistic manner; and (iv) utilization of redox-active ligands to influence the spin state of the metal. Redox-active ligands have emerged as useful tools to generate and control reactive metal-coordinated radicals, which give access to new synthetic methodologies and intricate (electronic) structures, some of which are yet to be exposed.

A novel photothermal molecular switch based on the reversible cyclization of 1H-2-benzo[c]oxocins to dihydro-4H-cyclobuta[c]isochromenes has been developed. The switching mechanism involves a light-triggered ring-contraction of 8 membered 1H-2-benzo[c]oxocins to 4,6-fused O heterocyclic dihydro-4H-cyclobuta[c]isochromene ring systems, with reversion back to the 1H-2-benzo[c]oxocin state accessible through heating. Both processes are unidirectional and proceed with good efficiency, with switching properties—including reversibility and half-life time—easily adjusted via structural functionalization. Our new molecular switching platform exhibits independence from solvent polarity, originating from it’s neutral-charge switching mechanism, a property highly sought after for biological applications. The photoinduced ring-contraction involves a [2+2] conjugated-diene cyclization that obeys the Woodward–Hoffmann rules. In contrast, the reverse process initiates via a thermal ring-opening (T > 60oC) to produce the anti-Woodward–Hoffmann product, proposed to proceed via an ortho-quinodimethane (o-QDM) intermediate. The proposed switching mechanisms are supported by experimental observations and density functional theory (DFT) calculations. Other transformations of 1H-2-benzo[c]oxocins were found upon altering reaction conditions: prolonged heating the 1H-2-benzo[c]oxocins at significantly elevated temperature (72 h at 120°C), with the resulting dihydronaphthalenes formed via the o QDM intermediate. These reactions also proceed with good chemoselectivities, providing new synthetic protocols for motifs found in several bioactive molecules, but are otherwise difficult to access.

The gender gap, which is thought to mediate students’ future career trajectory, remains an issue in science education communities over the past decades. Although many factors can contribute to the gender gap in science, textbooks are one of important factors considering their empowering role in shaping students’ attitudes toward gender and projecting their own gender roles in science. How gender is represented in visual matters in biological science textbooks is rarely charted. This study intended to explore the extent to which the illustrations in six biological science textbooks for secondary schools advocate an egalitarian gender ideology by mapping the ratio of female-to-male and enquiring how males and females were rendered through the three dimensions of representational, compositional and interactive meaning of social semiotic theory. The findings reveal that the textbooks appear to be gender neutral at face value since the social semiotic analysis of the individuals in the illustrations suggests that males and females are portrayed impartially. However, the textbooks persist in a sexist ideology through the way in which the quantitative inequality of the two sexes, successful role models and research activities as well as the subtle and nuanced strategies employed by the textbooks to downplay successful female role models and to portray women in more assistant and subordinate roles in professional activities. The gendered message delivered in the textbooks has the potential to disempower female students’ career aspiration and influence their perceptions of their roles in science in relation to their gender.

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Cyclic arginine-glycine-aspartic (RGD) peptides that specifically bind to integrin α

The design and synthesis of metal–organic framework/graphene oxide (MOF/GO) composites are vital for their applications in energy, adsorption, sensing, supercapacitors, and catalysis. How to achiev...

It is preliminary estimated that the proved geological reserves of original low-oil-saturation reservoirs (OLOSRs) of 54 blocks in China are more than 820 million tons. As same as the high water-cut stage of a reservoir after water flooding, the initial water cut of OLOSRS is higher than 80%. The industrial application of EOR technology could efficiently enhance oil recovery rate from 8.4% to 20.1% of reservoirs after water flooding. The suitable measurements of EOR to the OLOSRs probably have a profound impact on achieving higher oilfield reserves and production. In this paper, the main characteristics and reserves potential of OLOSRs have been studied by investigations and laboratory experiments. The relationship between initial oil saturation and displacement efficiency is also analyzed. The feasibility of EOR technologies for different OLOSRs is discussed. The results show that the OLOSRs could be divided into two categories (primary and secondary) by origin of low oil saturation. The two categories contain abundant reserves in China’s major oilfields, but their occurrence states of crude oil are quite different. If the average oil saturation of the OLOSR is defined at 40%, there are 13.1%–54.2% crude oil that could be recovered by using the existing EOR technology, especially in the primary OLOSRs with low permeability and the secondary OLOSRs with high permeability. Keywords: Low oil saturation, Transition zones, Occurrence state, Oil displacement efficiency, Gas flooding, Surfactant flooding

The carbohydrate-active enzyme (CAZyme) genes of Trametes contribute to polysaccharide degradation. However, the comprehensive analysis of the composition of CAZymes and the biosynthetic gene clusters (BGCs) of Trametes remain unclear. Here, we conducted comparative analysis, detected the CAZyme genes, and predicted the BGCs for nine Trametes strains. Among the 82,053 homologous clusters obtained for Trametes, we identified 8518 core genes, 60,441 accessory genes, and 13,094 specific genes. A large proportion of CAZyme genes were cataloged into glycoside hydrolases, glycosyltransferases, and carbohydrate esterases. The predicted BGCs of Trametes were divided into six strategies, and the nine Trametes strains harbored 47.78 BGCs on average. Our study revealed that Trametes exhibits an open pan-genome structure. These findings provide insights into the genetic diversity and explored the synthetic biology of secondary metabolite production for Trametes.

Growing evidence has demonstrated that in tumor progression, circular RNAs (circRNAs) play important roles. However, the roles of circRNAs in nasopharyngeal carcinoma (NPC) have not been fully elucidated. In this study, it was demonstrated that that hsa_circ_0033074 (circSERPINA3) expression was found to be significantly upregulated in NPC tissues and cell lines. CircSERPINA3 inhibition significantly attenuated the invasion and proliferation abilities of NPC cells. The mechanism by which circSERPINA3 interacted with miR-944 was identified and MDM2 was demonstrated to function as a target gene of miR-944. Rescue experiments showed that miR-944 inhibitors or MDM2 overexpression reserved the effects of circSERPINA3 knockdown on NPC progression. Therefore, our study uncovered the circSERPINA3/miR-944/MDM2 axis in NPC, which may be a potential NPC therapeutic target.

Communication when submitting patches (CSP) is critical in software development, because ineffective communication wastes the time of developers and reviewers, and is even harmful to future product release and maintenance. In distributed software development, CSP is usually in the form of computer-mediated communication (CMC), which is a crucial topic concerned by the CSCW community. However, what to say and how to say in communication including CSP has been rarely studied. To bridge this knowledge gap and provide relevant guidance for developers to conduct CSP, in this study, we conducted an empirical study on the Linux kernel. We found four themes involving 17 expression elements that characterize what to express when submitting patches and three themes of contextual factors that determine how these elements are applied. Considering both expression elements and context, combined with an online survey, we obtained 17 practices for communication. Among them, four practices, such as "provide sufficient reasons" and "provide a trade-off" are the most important but difficult practices, for which we provide specific instructions. We also found that the "individual factors" plays a special role in communication, which may lead to potential problems even in accepted patches. Based on these findings, we discuss the recommendations for different practitioners, including patch submitters, reviewers, and tool designers, and the implications for open source software (OSS) communities and the CSCW researchers.

With the continuous development of the internet, software development (especially global open-source development) is facing critical challenges, such as individual differences in developers distributed worldwide, the increasing difficulty of group collaboration, and the complex ecosystems formed by extensive social participation. These problems exhibit strong sociological characteristics in regard to the activity of software development. This study proposes the concept of software digital sociology that involves mining abundant software-activity data to investigate individual learning, group collaboration, and sustainable ecosystems. We discuss the primary investigation of the critical issues associated with the open-source supply chain and suggest that software digital sociology can inspire software-development researchers to understand the key challenges posed by extensive (computer-mediated) social participation to promote exploration of solutions using a different paradigm.

The metallo-radical activation of ortho-allylcarbonyl-aryl N-arylsulfonylhydrazones with the paramagnetic cobalt(II) porphyrin catalyst [CoII(TPP)] (TPP = tetraphenylporphyrin) provides an efficient and powerful method for the synthesis of novel 8-membered heterocyclic enol ethers. The synthetic protocol is versatile and practical and enables the synthesis of a wide range of unique 1H-2-benzoxocins in high yields. The catalytic cyclization reactions proceed with excellent chemoselectivities, have a high functional group tolerance, and provide several opportunities for the synthesis of new bioactive compounds. The reactions are shown to proceed via cobalt(III)-carbene radical intermediates, which are involved in intramolecular hydrogen transfer (HAT) from the allylic position to the carbene radical, followed by a near-barrierless radical rebound step in the coordination sphere of cobalt. The proposed mechanism is supported by experimental observations, density functional theory (DFT) calculations, and spin trapping experiments.