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Electroreductive cross-electrophile coupling has emerged as a powerful and efficient method for constructing challenging C–C or C–X bonds, providing several advantages including highly efficient electron transfer, tunable reducing potential, direct electricity-activation of substrates and good scalability. In electroreductive cross-electrophile coupling, a high loading of a transition metal catalyst is required to facilitate the transfer of electrons from the cathode to organic halides, making it unsuitable for sensitive organic halides such as chloroformates. As a result, the electroreductive XEC of readily accessible chloroformates with alkyl halides for ester synthesis remains a largely unmet challenge. In this work, catalyst-free electrochemically driven cross-electrophile esterification of alkyl halides has been developed. A wide range of 2-phenylacetic esters which represent an important class of molecules in synthetic and medicinal chemistry are accessed from simple and cheap alkyl halides and alkyl chloroformates under mild reaction conditions. Various functional groups were well tolerated, affording up to 98% yields. This protocol would contribute a lot for the further development of electrochemically driven cross-electrophile coupling. [ABSTRACT FROM AUTHOR]

Here, we present the synthesis of a novel quaternary compound, iodide carbonate Na5(CO3)2I, at 18(1) and 25.1(5) GPa in laser-heated diamond anvil cells. Single-crystal synchrotron X-ray diffraction provides accurate structural data for Na5(CO3)2I and shows that the structure of the material can be described as built of INa8 square prisms, distorted NaO6 octahedra, and trigonal planar CO32− units. Decompression experiments show that the novel iodide carbonate is recoverable in the N2 atmosphere to ambient conditions. Our ab initio calculations agree well with the experimental structural data, provide the equation of state, and shed light on the chemical bonding and electronic properties of the new compound. [ABSTRACT FROM AUTHOR]

With the increasing incidence of oral cancer in the world, it has become a hotspot to explore the pathogenesis and prevention of oral cancer. It has been proved there is a strong link between periodontal pathogens and oral cancer. However, the specific molecular and cellular pathogenic mechanisms remain to be further elucidated. Emerging evidence suggests that periodontal pathogens‐induced epithelial–mesenchymal transition (EMT) is closely related to the progression of oral cancer. Cells undergoing EMT showed increased motility, aggressiveness and stemness, which provide a pro‐tumour environment and promote malignant metastasis of oral cancer. Plenty of studies proposed periodontal pathogens promote carcinogenesis via EMT. In the current review, we discussed the association between the development of oral cancer and periodontal pathogens, and summarized various mechanisms of EMT caused by periodontal pathogens, which are supposed to play an important role in oral cancer, to provide targets for future research in the fight against oral cancer. [ABSTRACT FROM AUTHOR]

A series of isostructural Ln3O2(CN3) (Ln=La, Eu, Gd, Tb, Ho, Yb) oxoguanidinates was synthesized under high‐pressure (25–54 GPa) high‐temperature (2000–3000 K) conditions in laser‐heated diamond anvil cells. The crystal structure of this novel class of compounds was determined via synchrotron single‐crystal X‐ray diffraction (SCXRD) as well as corroborated by X‐ray absorption near edge structure (XANES) measurements and density functional theory (DFT) calculations. The Ln3O2(CN3) solids are composed of the hitherto unknown CN35− guanidinate anion—deprotonated guanidine. Changes in unit cell volumes and compressibility of Ln3O2(CN3) (Ln=La, Eu, Gd, Tb, Ho, Yb) compounds are found to be dictated by the lanthanide contraction phenomenon. Decompression experiments show that Ln3O2(CN3) compounds are recoverable to ambient conditions. The stabilization of the CN35− guanidinate anion at ambient conditions provides new opportunities in inorganic and organic synthetic chemistry. [ABSTRACT FROM AUTHOR]

Hand gesture recognition is an essential Human–Computer Interaction (HCI) mechanism for users to control smart devices. While traditional device-based methods support acceptable recognition performance, the recent advance in wireless sensing could enable device-free hand gesture recognition. However, two severe limitations are serious environmental interference and high-cost hardware, which hamper wide deployment. This paper proposes the novel system TaGesture, which employs an inaudible acoustic signal to realize device-free and training-free hand gesture recognition with a commercial speaker and microphone array. We address unique technical challenges, such as proposing a novel acoustic hand-tracking-smoothing algorithm with an Interaction Multiple Model (IMM) Kalman Filter to address the issue of localization angle ambiguity, and designing a classification algorithm to realize acoustic-based hand gesture recognition without training. Comprehensive experiments are conducted to evaluate TaGesture. Results show that it can achieve a total accuracy of 97.5% for acoustic-based hand gesture recognition, and support the furthest sensing range of up to 3 m. [ABSTRACT FROM AUTHOR]

Simple Summary: In this paper, two new genera with two new species of Dermaptera are described from the Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China. The discovery of these two new species enriches the comparatively meagre fossil record of Dermaptera, particularly from the Middle Jurassic. The description of Applanatiforceps angustus is another brick laid in the foundation of protodiplatyid diversity, and the new genus Ekpagloderma gracilentum highlights the diversity of cercal forms among Aglyptodermatinae and the remarkable homogeneity of the general morphology of groups within this clade. Two new genera and species of Dermaptera are described from the Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China: Applanatiforceps angustus gen. et sp. nov. in the archidermapteran family Protodiplatyidae, and Ekpagloderma gracilentum gen et sp. nov. in the eodermapteran family Semenoviolidae. Applanatiforceps shares the typical characters of the extinct suborder Archidermaptera (e.g., pentamerous meta tarsi, filiform and multimerous cerci) and externalized ovipositor. The family identity of the Protodiplatyidae can be further distinguished by comparing this new genus with other genera of the Protodiplatyidae. As a result of its large compound eyes, tegmina without venation, body sparsely setose, legs rather short and slender, and shape of the veinless tegmina, Ekpagloderma is classified in the subfamily Aglyptodermatinae. Ekpagloderma not only has the typical features of the Aglyptodermatinae, but also exhibits a more primitive slender segmented cerci, which is different from all other genera of Eodermaptera. In fact, the diversity of Eodermaptera as known today indicates some of the challenges in understanding the suborder and whether or not it is monophyletic as historically construed, or if the separation of Turanodermaptera is justified. [ABSTRACT FROM AUTHOR]