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Head-gaze interaction is an integral mode of interaction in virtual reality (VR) applications, demonstrating high precision in fine manipulation tasks but low efficiency in large-scale object movements. To enhance the efficiency of head-gaze interaction, this study adjusted the control-display gain to compensate for the weaknesses of head-gaze interaction in a long-distance object-positioning task. We investigated the effect of the control-display gain of head-gaze interaction on movement time (MT) using a cohort of participants (n = 24) to perform experiments. The results showed that the MT first decreased as the gain increased from 1 to 1.5 and then increased afterwards. Further analysis showed that a high gain improved the interaction efficiency in the ballistic phase, but reduced the interaction efficiency in the corrective phase. To be able to obtain higher efficiency of interaction, we designed a dual-gain mode which set different gains in the ballistic and corrective phases. Evaluated using an additional experimental cohort (n = 24), our results showed that the dual-gain mode was more efficient than the mono-gain mode. Moreover, the dual-gain mode with optimal gains did not induce a more serious perception of inconsistency, confusion, nonacceptance and motion sickness, while it had a tendency to reduce the total workload compared to the interaction with normal gain. Our findings provide potential valuable design insights and guidance contributing to improving the efficiency of head-gaze interaction in virtual spaces. [ABSTRACT FROM AUTHOR]

Accurate identifying and in‐depth understanding of the defect sites in a working nanomaterial could hinge on establishing specific defect‐activity relationships. Yet, atomically precise coinage‐metal nanoclusters (NCs) possessing surface vacancy defects are scarce primarily owing to challenges in the synthesis and isolation of such defective NCs. Herein we report a mixed‐ligand strategy to synthesizing an intrinsically chiral and metal‐deficient copper hydride‐rich NC [Cu57H20(PET)36(TPP)4]+ (Cu57H20). Its total structure (including hydrides) and electronic structure are well established by combined experimental and computational results. Crystal structure reveals Cu57H20 features a cube‐like Cu8 kernel embedded in a corner‐missing metal‐ligand shell of Cu49(PET)36(TPP)4. Single Cu vacancy defect site occurs at one corner of the shell, evocative of mono‐lacunary polyoxometalates. Theoretical calculations demonstrate that the above‐mentioned point vacancy causes one surface hydride exposed as an interfacial capping μ3‐H−, which is accessible in chemical reaction, as proved by deuterated experiment. Moreover, Cu57H20 shows catalytic activity in the hydrogenation of nitroarene. The success of this work opens the way for the research on well‐defined chiral metal‐deficient Cu and other metal NCs, including exploring their application in asymmetrical catalysis. [ABSTRACT FROM AUTHOR]

Bimetallic cluster ion pairs containing a quaternary phosphonium and an ultrasmall Cu2Ag3 anionic cluster protected by thiolates: (PPh3R′′)[Cu2Ag3(SR′)6] (R′SH = cyclohexylthiol (CySH), R′′ = Ph, 1; Me, 2; Et, 3; Pr, 4; R′SH = tert-butylthiol (tBuSH) and R′′ = Ph, 5) were reported. Without any chiral source, 1 crystallizes as conglomerate crystals with homochiral packings and spontaneous resolution occurs, while four other clusters 2–5 crystallize as racemic crystals with heterochiral packings. These results indicate that racemic and homochiral crystallization in the cluster system could be controlled through fine-tuning internal achiral structural components. [ABSTRACT FROM AUTHOR]

Paleo‐Pacific subduction generated a prolonged active continental margin along the coast of the South China Block (SCB). A Triassic magmatic gap was argued to have occurred and was ascribed to flat‐slab subduction of an oceanic plateau. We study for the first time a >330‐m‐long core of typical arc volcanics dated at ca. 218 Ma from the Meiji Atoll in the southern South China Sea (SCS). Paleomagnetism suggests 4.1°± 1.5° of post‐eruption southward drift. These observations clearly support the existence of a Triassic arc in the SCB and imply that part of the arc later split off and drifted southward during the opening of the SCS in the Oligocene. Our results better constrain the lateral extent of the proposed flat‐slab subduction along the margin of the SCB. Moreover, we provide direct evidence of how the breakaway of ribbon continents operated in active continental margins, a recurrent scenario that has been invoked for Phanerozoic tectonics and continental growth throughout Asia. [ABSTRACT FROM AUTHOR]

The interplay between Pleistocene climatic variability and hominin adaptations to diverse terrestrial ecosystems is a key topic in human evolutionary studies. Early and Middle Pleistocene environmental change and its relation to hominin behavioural responses has been a subject of great interest in Africa and Europe, though little information is available for other key regions of the Old World, particularly from Eastern Asia. Here we examine key Early Pleistocene sites of the Nihewan Basin, in high-latitude northern China, dating between ∼1.4 and 1.0 million years ago (Ma). We compare stone-tool assemblages from three Early Pleistocene sites in the Nihewan Basin, including detailed assessment of stone-tool refitting sequences at the ∼1.1-Ma-old site of Cenjiawan. Increased toolmaking skills and technological innovations are evident in the Nihewan Basin at the onset of the Mid-Pleistocene Climate Transition (MPT). Examination of the lithic technology of the Nihewan sites, together with an assessment of other key Palaeolithic sites of China, indicates that toolkits show increasing diversity at the outset of the MPT and in its aftermath. The overall evidence indicates the adaptive flexibility of early hominins to ecosystem changes since the MPT, though regional abandonments are also apparent in high latitudes, likely owing to cold and oscillating environmental conditions. The view presented here sharply contrasts with traditional arguments that stone-tool technologies of China are homogeneous and continuous over the course of the Early Pleistocene. [ABSTRACT FROM AUTHOR]

Silver clusters with atomic precision have garnered immense attention owing to their aesthetic structures and fascinating properties. Assembly of silver clusters involves organizing positively charged silver ions into an intricate entity in an ordered fashion. To this end, the established effective route to assemble well-ordered silver clusters uses facile template anions as structure-directing agents. The past decades have witnessed a single anion template strategy widely used to construct silver clusters. In order to overcome the nuclearity limitation from the single anion template, multiple anionic templates have been recently introduced into the controllable preparation of high-nuclearity silver clusters. In this highlight, we will summarize the recent advances in homo- and hetero-anion templated silver clusters, in which their synthetic methods, crystal structures and anionic template directing effects as well as properties will be discussed. [ABSTRACT FROM AUTHOR]

The Nihewan Basin of China preserves one of the most important successions of Paleolithic archeological sites in Eurasia. Stratified archeological sites and mammalian fossils, first reported in the 1920s, continue to be recovered in large‐scale excavation projects. Here, we review key findings from archeological excavations in the Nihewan Basin ranging from ~1.66 Ma to 11.7 ka. We place particular emphasis on changes in stone tool technology over the long term. Though Pleistocene lithic industries from East Asia are often described as simple in character, re‐evaluation of the stone tool evidence from the Nihewan Basin demonstrates significant, though periodic, innovations and variability in manufacturing techniques through time, indicating adaptive and technological flexibility on the part of hominins. Synthesis of paleoenvironmental and archeological data indicate changes in hominin occupation frequency in the Nihewan Basin, with chronological gaps suggesting that continuous presence in high, seasonal latitudes was not possible prior to the Late Pleistocene. [ABSTRACT FROM AUTHOR]

Objective: The study examines the factors determining the movement time (MT) of positioning an object in an immersive 3D virtual environment.Background: Positioning an object into a prescribed area is a fundamental operation in a 3D space. Although Fitts's law models the pointing task very well, it does not apply to a positioning task in an immersive 3D virtual environment since it does not consider the effect of object size in the positioning task.Method: Participants were asked to position a ball-shaped object into a spherical area in a virtual space using a handheld or head-tracking controller in the ray-casting technique. We varied object size (OS), movement amplitude (A), and target tolerance (TT). MT was recorded and analyzed in three phases: acceleration, deceleration, and correction.Results: In the acceleration phase, MT was inversely related to object size and positively proportional to movement amplitude. In the deceleration phase, MT was primarily determined by movement amplitude. In the correction phase, MT was affected by all three factors. We observed similar results whether participants used a handheld controller or head-tracking controller. We thus propose a three-phase model with different formulae at each phase. This model fit participants' performance very well.Conclusion: A three-phase model can successfully predict MT in the positioning task in an immersive 3D virtual environment in the acceleration, deceleration, and correction phases, separately.Application: Our model provides a quantitative framework for researchers and designers to design and evaluate 3D interfaces for the positioning task in a virtual space. [ABSTRACT FROM AUTHOR]

The uplift history of south-eastern Tibet is crucial to understanding processes driving the tectonic evolution of the Tibetan Plateau and surrounding areas. Underpinning existing palaeoaltimetric studies has been regional mapping based in large part on biostratigraphy that assumes a Neogene modernization of the highly diverse, but threatened, Asian biota. Here, with new radiometric dating and newly collected plant-fossil archives, we quantify the surface height of part of the south-eastern margin of Tibet in the latest Eocene (∼34 Ma) to be ∼3 km and rising, possibly attaining its present elevation (3.9 km) in the early Oligocene. We also find that the Eocene–Oligocene transition in south-eastern Tibet witnessed leaf-size diminution and a floral composition change from sub-tropical/warm temperate to cool temperate, likely reflective of both uplift and secular climate change, and that, by the latest Eocene, floral modernization on Tibet had already taken place, implying modernization was deeply rooted in the Palaeogene. [ABSTRACT FROM AUTHOR]

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]

Donggutuo (DGT) is one of the richest archaeological localities in the Nihewan Basin of North China, thereby providing key information about the technological behaviours of early hominins in eastern Asia. Although DGT has been subject of multiple excavations and technological studies over the past several decades, few detailed studies on the lithic assemblages have been published. Here we summarize and describe the DGT lithic assemblages, examining stone tool reduction methods and technological skills. DGT dates to ca. 1.1 Ma, close to the onset of the mid-Pleistocene climate transition (MPT), indicating that occupations at DGT coincided with increased environmental instability. During this time interval, the DGT knappers began to apply innovative flaking methods, using free hand hard hammer percussion (FHHP) to manufacture pre-determined core shapes, small flakes and finely retouched tools, while occasionally using the bipolar technique, in contrast to the earlier and nearby Nihewan site of Xiaochangliang (XCL). Evidence for some degree of planning and predetermination in lithic reduction at DGT parallels technological developments in African Oldowan sites, suggesting that innovations in early industries may be situational, sometimes corresponding with adaptations to changes in environments and local conditions. [ABSTRACT FROM AUTHOR]

ABSTRACT The Lesser Khingan Mountains of north-eastern China are heavily forested, making archaeological site identification difficult owing to poor ground surface visibility. Nevertheless, several prehistoric archaeological site discoveries have been made in recent years and a limited number of excavations have been initiated. One of the most important sites to emerge is Taoshan, which has yielded stratified stone tool assemblages dating from the Last Glacial Maximum (LGM) to the mid-Holocene. Pollen profiles indicate significant changes in vegetation, fluctuating from steppe conditions during the LGM to forested conditions in the Bølling-Allerød interstadial (B-A) and the mid-Holocene. The stone tool assemblages from Taoshan were primarily produced from varieties of volcanic tuff, rhyolite, hornfels and agate. Geological prospecting and petrological analyses were performed to document procurement sources and changes in raw material exploitation strategies. During the LGM, the predominant raw material was vitric tuff, available from a source ca. 5-10 km from Taoshan. In the B-A and mid-Holocene layers, emphasis was on the exploitation of raw materials in gravel bars, although stone tool reduction techniques and raw material preferences changed considerably during this time interval. Diachronic changes in raw materials and exploitation strategies correspond to changes in vegetation and human adaptations. [ABSTRACT FROM AUTHOR]

Three diiron and tetrairon azadithiolate complexes as models for the active site of [FeFe] hydrogenase were prepared. Reaction of complex Fe2(SCH2OH)2(CO)6 and NH2CH2CH2CH2OCH3 resulted in the diiron azadithiolate hexcarbonyl complex Fe2[(SCH2)2- NCH2CH2CH2OCH3](CO)6 (1) in moderate yield. Furthermore, treatment of complex 1 with mono phosphine ligand PPh3 and diphosphine ligand PH2PCH2CH2PPH2 in the presence of decarbonylation reagent Me3NO·2H2O yielded the phosphine-substituted azadithiolate complexes Fe2[(SCH2)2NCH2CH2CH2OCH3]CO)5(PPh3) (2) and {Fe2[(SCH2)2NCH2CH2CH2OCH3](CO)5}2(PH2PCH2CH2PPH2) (3) respectively. The new complexes 1-3 were fully characterized by elemental analysis, IR, ¹H, 13C, 31P NMR spectroscopy and X-ray crystallography. It is worthy to note that the crystallographic studies show the unusual difference of the methoxypropanyl substituent on the N atom of complexes 1 and 2, largely because of the affection of phosphine ligand PPh3. In addition, complex 1 was found to be a catalyst for H2 production under electrochemical condition. [ABSTRACT FROM AUTHOR]

Xiaochangliang (XCL), located in the Nihewan Basin of North China, is a key archaeological locality for understanding the behavioural evolution of early humans. XCL dates to ca. 1.36 Ma, making it one of the earliest sites in Northeast Asia. Although XCL represents the first excavation of an Early Pleistocene site in the Nihewan Basin, identified and excavated in the 1970’s, the lithic assemblages have never been published in full detail. Here we describe the lithic assemblages from XCL, providing information on stone tool reduction techniques and the influence of raw materials on artefact manufacture. The XCL hominins used both bipolar and freehand reduction techniques to manufacture small flakes, some of which show retouch. Bipolar reduction methods at XCL were used more frequently than previously recognized. Comparison of XCL with other Early Pleistocene sites in the Nihewan Basin indicates the variable use of bipolar and freehand reduction methods, thereby indicating a flexible approach in the utilization of raw materials. The stone tools from XCL and the Nihewan sites are classifiable as Mode I lithic assemblages, readily distinguished from bifacial industries manufactured by hominins in Eastern Asia by ca. 800 ka. [ABSTRACT FROM AUTHOR]

Six new O‐alkyldithiophosphate nickel complexes with dcpf ligand, [(dcpf)Ni(S2P{O}OR)] (dcpf = 1,1′‐bis (dicyclohexylphosphino)ferrocene, R = CH3 (1), CH3CH2 (2), Ph (3), 4‐MeC6H4 (4), PhCH2 (5) and PhCH2CH2 (6)), have been synthesized by the treatment of dcpf with ((RO)2PS2)2Ni in satisfactory yields. These complexes were characterized by elemental analysis, spectroscopy (FTIR, UV–vis, 1H, 13C, and 31P NMR), thermogravimetric analysis and single crystal X‐ray diffraction. The nickel atom in 1, 2·CH2Cl2, 3·CH2Cl2, 4·2CH2Cl2·THF, and 2(5)·hexane adopts a slightly distorted square‐planar coordination environment finished by two phosphorus atoms of dcpf ligand and two sulfur atoms of O‐alkyldithiophosphate ligand. Furthermore, the electrochemical properties for complexes 1–6 were also investigated by cyclic voltammetry. With the addition of 120 mM trifluoroacetic acid (TFA), the turnover frequency (TOF) values for 1–6 are estimated to be 1243.83, 1046.54, 1331.71, 2545.29, 1899.03, and 1191.37 s−1, with the overpotential (η) values of 0.62, 0.58, 0.71, 0.67, 0.60, and 0.56 V, respectively. The result of electrochemical studies indicates that all complexes can be used as efficient molecular eletrocatalysts for the reduction of protons to hydrogen in the presence of TFA in MeCN. [ABSTRACT FROM AUTHOR]

The fluvio-lacustrine sequences in the Nihewan Basin, northern China provide an important source of Paleolithic settlements and therefore early human occupation in the eastern Old World. Here we present electron spin resonance (ESR) chronology for the Majuangou (MJG-III, MJG-II and MJG-I) and Banshan (BS) Paleolithic sites in this basin by the quartz Ti-Li center ESR dating. Results show that the ages of MJG-III and MJG-II could be estimated to be ~1.70 Ma (millions of years ago); of MJG-I, ~1.40 Ma; and BS, ~1.35 Ma. This ESR chronology is consistent with the previous magnetochronology, thus providing strong support for the earliest human presence at the high northern latitudes of Northeast Asia. [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]

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]

Organized flaking techniques to obtain predetermined stone tools have been traced back to the early Acheulean (also known as mode 2) in Africa and are seen as indicative of the emergence of advanced technical abilities and in-depth planning skills among early humans. Here, we report one of the earliest known examples of prepared core technology in the archaeological record, at the Cenjiawan (CJW) site in the Nihewan basin of China, dated 1.1 Mya. The operational schemes reconstructed from the CJW refit sets, together with shaping patterns observed in the retouched tools, suggest that Nihewan basin toolmakers had the technical abilities of mode 2 hominins, and developed different survival strategies to adapt to local raw materials and environments. This finding predates the previously earliest known prepared core technology from Eurasia by 0.3 My, and the earliest known mode 2 sites in East Asia by a similar amount of time, thus suggesting that hominins with advanced technologies may have migrated into high latitude East Asia as early as 1.1 Mya., Competing Interests: Competing interests statement:The authors declare no competing interest.

Accurate identifying and in-depth understanding of the defect sites in a working nanomaterial could hinge on establishing specific defect-activity relationships. Yet, atomically precise coinage-metal nanoclusters (NCs) possessing surface vacancy defects are scarce primarily owing to challenges in the synthesis and isolation of such defective NCs. Herein we report a mixed-ligand strategy to synthesizing an intrinsically chiral and metal-deficient copper hydride-rich NC [Cu 57 H 20 (PET) 36 (TPP) 4 ] + (Cu 57 H 20 ). Its total structure (including hydrides) and electronic structure are well established by combined experimental and computational results. Crystal structure reveals Cu 57 H 20 features a cube-like Cu 8 kernel embedded in a corner-missing metal-ligand shell of Cu 49 (PET) 36 (TPP) 4 . Single Cu vacancy defect site occurs at one corner of the shell, evocative of mono-lacunary polyoxometalates. Theoretical calculations demonstrate that the above-mentioned point vacancy causes one surface hydride exposed as an interfacial capping μ 3 -H - , which is accessible in chemical reaction, as proved by deuterated experiment. Moreover, Cu 57 H 20 shows catalytic activity in the hydrogenation of nitroarene. The success of this work opens the way for the research on well-defined chiral metal-deficient Cu and other metal NCs, including exploring their application in asymmetrical catalysis., (© 2023 Wiley-VCH GmbH.)

The interplay between Pleistocene climatic variability and hominin adaptations to diverse terrestrial ecosystems is a key topic in human evolutionary studies. Early and Middle Pleistocene environmental change and its relation to hominin behavioural responses has been a subject of great interest in Africa and Europe, though little information is available for other key regions of the Old World, particularly from Eastern Asia. Here we examine key Early Pleistocene sites of the Nihewan Basin, in high-latitude northern China, dating between ∼1.4 and 1.0 million years ago (Ma). We compare stone-tool assemblages from three Early Pleistocene sites in the Nihewan Basin, including detailed assessment of stone-tool refitting sequences at the ∼1.1-Ma-old site of Cenjiawan. Increased toolmaking skills and technological innovations are evident in the Nihewan Basin at the onset of the Mid-Pleistocene Climate Transition (MPT). Examination of the lithic technology of the Nihewan sites, together with an assessment of other key Palaeolithic sites of China, indicates that toolkits show increasing diversity at the outset of the MPT and in its aftermath. The overall evidence indicates the adaptive flexibility of early hominins to ecosystem changes since the MPT, though regional abandonments are also apparent in high latitudes, likely owing to cold and oscillating environmental conditions. The view presented here sharply contrasts with traditional arguments that stone-tool technologies of China are homogeneous and continuous over the course of the Early Pleistocene., (© The Author(s) 2020. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

The abnormal activation of PI3K signaling pathway leads to the occurrence of various cancers. The PI3Kα is frequently mutated and overexpressed in many human cancers. Therefore, the PI3Kα was considered as a promising target in therapeutic treatment of cancer. In this study, two series of compounds containing 2H-benzo[b][1,4]oxazin-3(4H)-one and 2H-benzo[b][1,4]oxazine scaffold were synthesized and evaluated antiproliferative activities against three cancer cell lines, including HCT-116, MDA-MB-231 and SNU638. Compound 7f with the most potent antiproliferative activity was selected for further evaluation on normal cells and PI3K kinase. Studies indicated that compound 7f could decrease the phospho-Akt (T308) in a dose-dependent manner. Four key hydrogen bonding interactions were found in the docking of 7f with PI3K enzyme. All the results suggested that 7f was a potent PI3Kα inhibitor., (Copyright © 2018. Published by Elsevier Ltd.)