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Graphical abstract Six new aromatic dithiolate nickel complexes [RN(PPh 2) 2 Ni(bdt)] and [RN(PPh 2) 2 Ni(tdt)] have been synthesized and fully characterized. The nickel atom adopts a slightly distorted square-planar coordination by RN(PPh 2) 2 and dithiolate ligands. All complexes can electrocatalyze protons reduction to H 2 in the presence of FTA. Abstract Six aromatic dithiolate nickel complexes bearing N - substituted bis(diphenylphosphanyl)amine (RN(PPh 2) 2) ligands, [RN(PPh 2) 2 Ni(bdt)] (bdt = 1,2-benzenedithiolate; R = (CH 2) 3 OCH 3 (1), (CH 2) 3 SCH 3 (2), CH(CH 3)C 6 H 5 (3)) and [RN(PPh 2) 2 Ni(tdt)] (tdt = 3,4-toluenedithiolate; R = (CH 2) 3 OCH 3 (4), (CH 2) 3 SCH 3 (5), CH(CH 3)C 6 H 5 (6)), have been synthesized in moderated yields by condensations of RN(PPh 2) 2 NiCl 2 with 1,2-benzenedithiol or 3,4-toluenedithiol in the presence of Et 3 N at room temperature. All the complexes were fully characterized by elemental analysis, FTIR, NMR (1H, 13C, and 31P) spectroscopy, UV–Vis spectrum, and thermo-gravimetric analysis. The crystal structures of complexes 1 , 2 , 3 , and 5 have been investigated by single crystal X-ray diffraction. The nickel atom adopts a slightly distorted square-planar coordination by two phosphorus atoms of RN(PPh 2) 2 and two sulfur atoms of aromatic dithiolate ligands in their structures. Furthermore, the electrochemical behaviors of complexes 1 – 6 and their catalytic activities for electrochemical hydrogen evolution in CH 2 Cl 2 solution with trifluoroacetic acid (TFA) as a proton source have been studied by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

The overexpression of EGFR correlates with rapidly progressive disease, resistance to chemotherapy and poor prognosis. In certain human cancers, PI3K works synergistically with EGFR to promote proliferation, survival, invasion and metastasis. Development of dual-target drugs against EGFR and PI3K has therapeutic advantage and was an attractive approach against tumors. In this work, based on the molecular docking and previous studies, a series of 4-aminoquinazolines derivatives containing 6-sulfonamide substituted pyridyl group were rationally designed and identified as potent EGFR and PI3K dual inhibitors. The cytotoxicity experiment results showed that this series of compounds could effectively inhibit cell growth. The kinase assay demonstrated that 6c and 6i had high inhibition for EGFR and selectivity for PI3Kα distinguished from other isoforms. Further experiments showed that 6c could induce cell cycle arrest in G1 phase and apoptosis in BT549 cells. The western blot assay indicated that 6c inhibited the proliferation of BT549 cell through EGFR and PI3Kα/Akt signaling pathway. Our study suggested that compound 6c was a potential dual inhibitors of EGFR and PI3Kα. [ABSTRACT FROM AUTHOR]

Eye-gaze and head-gaze are two hands-free interaction modes in virtual reality, each of which has demonstrated different strengths. Selecting suitable interaction modes in different scenarios is important to achieve efficient interaction in virtual scenes. This study compared the movement time in an object positioning task by examining eye-gaze interaction and head-gaze interaction in various conditions. In turn, it identified the superior zones for each mode, respectively. Based on this information, we designed a combination mode - utilizing eye-gaze interaction at the acceleration phase and deceleration phase and head-gaze interaction at the correction phase - to achieve the optimal interaction mode, which has allowed us to obtain higher efficiency and subjective satisfaction. This study provides a comprehensive analysis of the characteristics of the eye-gaze and head-gaze interaction modes and provides valuable insights into selecting the appropriate interaction modes for virtual reality applications. [ABSTRACT FROM AUTHOR]

Accumulated studies in substance use disorders indicated that the mesocorticolimbic reward circuit and executive control circuit played interactive roles in the cue-reactivity and gamma oscillatory in the cortex, as well as autonomic nervous activity was associated with it. This study aimed to explore the mechanism of processing drug-related cues. Sixty methamphetamine users were recruited and exposed to the drug-related virtual reality (VR) environments. Self-reported craving was assessed and skin conductance level (SCL) and heart rate variability were used to measure the autonomic nervous reactivity. With source estimation, gamma current density was used to measure the activity of medial prefrontal cortex/orbitofrontal cortex (MPFC/OFC) and dorsolateral prefrontal cortex (DLPFC) which are responsible for the mesocorticolimbic reward circuit and the executive control circuit. The VR drug-related cue induced an increased craving and SCL compared with the neutral condition. Gamma activity in MPFC/OFC and right DLPFC were decreased after cue exposure and predicted the SCL changes. However, no association was found between self-reported craving and electrophysiological response. Cue-reactivity in cortex and ANS, as well as their association, were observed in this study. Cue-induced electrophysiological responses were related to gamma activity in the mesocorticolimbic reward circuit and the executive control circuit. [ABSTRACT FROM AUTHOR]

Knowledge about the Early and Middle Pleistocene hominin record of China is steadily increasing owing to the on-going implementation of palaeoanthropological surveys and excavations. Yet, relatively little attention has been paid to the effects of climate variability on hominin populations in China and its influence on archaeological site distributions and hominin behaviours. The Mid-Pleistocene climate transition (MPT), dating to between ∼1.2–0.7 Ma in Eastern Asia, is characterized by significant changes in the length and intensity of glacial-interglacial cycles and in monsoon intensity and terrestrial conditions, which have been implicated in influencing the occupation history of basins within China. Here, the MPT is examined relative to archaeological site distributions across China to determine potential long-term geographic and behavioural effects on hominin populations before, during and after this critical period. Changes in the geographic distribution of hominins are demonstrated across the MPT, with significant shifts in the number of sites in high and low latitudes, likely as a response to changing ecosystems. Technological innovations, including the development of Large Cutting Tools, occur in the MPT and afterwards, possibly a response to the formation of open habitats in South China. Geographic and behavioural shifts in the hominin record challenge traditional views about the long-term, conservative nature of the biological and cultural evolution of hominins in Eastern Asia, and instead demonstrate dynamic responses of populations to ecosystem changes across the Early and Middle Pleistocene. • An up-to-date review of the Early and Middle Pleistocene hominin record of China. • Hominin site distributions changed across the Mid-Pleistocene climate transition (MPT). • Technological innovations occurred in the MPT and afterwards. • The shifts across the MPT indicate that early hominins were effected by, and responded to ecosystem changes. [ABSTRACT FROM AUTHOR]

Five heteroleptic maleonitriledithiolate nickel complexes bearing bis(diphenyl-phosphanyl)amine ligands, RN(PPh 2) 2 Ni(mnt), have been synthesized and structurally characterized. The coordination geometry around the nickel atom is a slightly distorted square-planar configuration. All complexes can electrocatalyze reduction of protons to hydrogen in the presence of trifluoroacetic acid in MeCN. • The nickel atom in the crystal structure of the complexes adopts a slightly distorted square-planar coordination environment. • The complexes are stable under acidic and electrochemical conditions. • The complexes can be used as low-cost robust molecular eletrocatalysts for hydrogen evolution. • ECEC mechanism for electrocatalytic hydrogen evolution has been proposed. Five neutral heteroleptic maleonitriledithiolate nickel complexes [RN(PPh 2) 2 Ni(mnt)] bearing bis(diphenylphosphanyl)amine ligands (where mnt2− = maleonitriledithiolate; R = CH 3 O(CH 2) 3 (1), CH 3 S(CH 2) 3 (2), (S)-CH 3 CHPh (3), (CH 3) 2 CH(CH 2) 2 (4), and p- CH 3 C 6 H 4 (5)) have been synthesized and fully characterized by elemental analysis, FTIR, NMR (1H, 13C, and 31P) spectroscopy, UV–Vis spectrum, single crystal X-ray diffraction, thermogravimetric analysis, and density functional theory (DFT) calculation. The nickel atom in 1 , 2 , 4 , and 5 ⋅1.5CH 2 Cl 2 adopts a slightly distorted square-planar coordination environment with two phosphorus atoms of RN(PPh 2) 2 and two sulfur atoms of mnt2−, respectively, while the nickel atom in 3 exhibits a pseudo square pyramid with HP 2 S 2 chromophore. Furthermore, the electrochemical properties for 1 – 5 were also investigated by cyclic voltammetry. With the addition of 120 mM trifluoroacetic acid (TFA) to 1 – 5 in MeCN, the turnover frequency (TOF) values are estimated to be 368.59–585.17 s−1 with the corresponding overpotential (η) values of 0.59–0.73 V. The electrochemical studies indicate that all complexes can be used as low-cost robust molecular eletrocatalysts for the reduction protons to hydrogen in the presence of TFA and a possible ECEC mechanism for electrocatalytic hydrogen evolution has been also proposed. [ABSTRACT FROM AUTHOR]