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Enzymes are considered safe and effective therapeutic tools for various diseases. With the increasing integration of biomedicine and nanotechnology, artificial nanozymes offer advanced controllability and functionality in medical design. However, several notable gaps, such as catalytic diversity, specificity and biosafety, still exist between nanozymes and their native counterparts. Here we report a non‐metal single‐selenium (Se)‐atom nanozyme (SeSAE), which exhibits potent nicotinamide adenine dinucleotide phosphate (NADPH) oxidase‐mimetic activity. This novel single atom nanozyme provides a safe alternative to conventional metal‐based catalysts and effectively cuts off the cellular energy and reduction equivalents through its distinctive catalytic function in tumors. In this study, we have demonstrated the substantial efficacy of SeSAE as an antitumor nanomedicine across diverse mouse models without discernible systemic adverse effects. The mechanism of the NADPH oxidase‐like activity of the non‐metal SeSAE was rationalized by density functional theory calculations. Furthermore, comprehensive elucidation of the biological functions, cell death pathways, and metabolic remodeling effects of the nanozyme was conducted, aiming to provide valuable insights into the development of single atom nanozymes with clinical translation potential. [ABSTRACT FROM AUTHOR]

Accurate traffic flow forecasting is a critical component in intelligent transportation systems. However, most of the existing traffic flow prediction algorithms only consider the prediction under normal conditions, but not the influence of weather attributes on the prediction results. This study applies a hybrid deep learning model based on multi feature fusion to predict traffic flow considering weather conditions. A comparison with other representative models validates that the proposed spatial‐temporal fusion graph convolutional network (STFGCN) can achieve better performance. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the instability for Rayleigh–Taylor problem of three‐dimensional incompressible non‐Newtonian fluids with Eills‐type. If the density profile in equilibrium‐state is heavier with increasing height, we prove that the equilibrium‐state solution is unstable under H3$$ {H}^3 $$‐norm by exploiting a bootstrap method. [ABSTRACT FROM AUTHOR]

Chemotherapy drugs, though effective against cancer, often pose challenges due to their high toxicity and adverse effects. To address these issues and prevent premature drug release, a straightforward yet smart glutathione (GSH)‐responsive drug delivery system (DDS) based on aptamer‐coated mesoporous silica has been developed. Mesoporous silica serves as the drug carrier, with the anticancer drug model doxorubicin (Dox) efficiently loaded in, sealed by coating with aptamer AS1411. The characteristics of the resulting microspheres were investigated by transmission electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis and zeta potential measurements. These analyses confirmed the successful bonding of AS1411 to the surface of the mesoporous silica. Drug‐release tests were conducted under two distinct pH conditions (pH 5.0 and 7.4), both in the presence and in the absence of GSH. The results demonstrate the remarkable ability of this DDS to respond to GSH, facilitating controlled drug release. The single coated layer on the particle serves a dual purpose by blocking pore openings and triggering an endogenous stimulus response, ensuring the precise release of pharmaceuticals during drug delivery. This GSH‐responsive DDS holds the potential to mitigate drug‐induced harm to healthy tissues, offering a new approach for cancer treatment. [ABSTRACT FROM AUTHOR]

The excitons are generally decomposed into free charges by the heterojunction due to the low dielectric constant of organic materials. Recent research indicates that owing to the low exciton binding energy, the pure Y6 film can directly and spontaneously generate free charge carriers after photoexcitation, even without the assistance of the donor/acceptor interface driving force. However, the serious bimolecular recombination and trap‐assisted recombination also limit the photovoltaic efficiency of single‐component Y6 devices. Herein, efficient exciton separation and charge collection by changing the buffer layer and using mixed solvents to control the active layer morphology of single‐component devices based on Y6 are achieved. It is found that the short‐circuit current is significantly increased by properly adjusting the proportion of face‐on and edge‐on direction of molecules. Eventually, the power conversion efficiency (PCE) of single‐component devices based on Y6 is increased from 0.15% to 1.41%. The corresponding dynamic process is revealed by ultrafast transient absorption spectroscopy and entropy effect on the exciton dissociation. Effective charge separation and collection in single‐component devices is not only critical to improving the PCE, but provides an in‐depth understanding for the further design of high‐performance multicomponent devices. [ABSTRACT FROM AUTHOR]

Oxaliplatin (OXA) has been recognized as a third‐generation platinum‐based chemotherapeutic agent with stellar therapeutic efficacy in managing colorectal cancer (CRC). Nevertheless, resistance to OXA in CRC patients hinders its effectiveness. Shikonin (SHI), a natural naphthoquinone derived from Arnebia euchroma (Royle) Johnst., features a broad pharmacological profile and minimal toxicities. To assess the synergism of SHI and OXA towards OXA‐resistant CRC cells (HCT116R), we employed in vitro and in vivo pharmacological assays. Our experiments provided evidence that SHI, either alone or in combination with OXA, considerably reduced cell proliferation, triggered apoptosis, and induced the generation of reactive oxygen species (ROS) in HCT116R cells. Furthermore, the combination of SHI and OXA dramatically curbed the extent of HCT116R‐initiated xenograft growth in mouse models. Bioinformatics, western blot, and ROS assays highlighted that the mechanisms of SHI against OXA‐resistant CRC cells may involve the induction of cellular responses to chemical stress, intrinsic apoptosis, as well as endoplasmic reticulum stress pathways mediated by ROS. Notably, the synergism of SHI+OXA was partially abrogated by an ROS inhibitor N‐acetyl cysteine. Our findings imply the potential of SHI to boost the sensitivity of OXA to CRC, offering promising benefits for clinical strategies to combat OXA resistance. [ABSTRACT FROM AUTHOR]

Pipeline flow visualization of cemented tailings backfill slurry (CTBS) improves the safety and stability of transportation. High turbidity and low resolution make it difficult for conventional methods to monitor the particle distribution state of CTBS in a short period of time. Particle tracking technology (PTT) is used to simulate and investigate the flow characteristics of CTBS pipeline, combine with theoretical analysis to construct a CTBS pipeline visualization model, elaborate the particle distribution state when CTBS flows in the pipeline, and explore the effects of pipe diameter (PD), flow velocity (FV) and tailings gradation (TG) on the particle distribution. The results show that particle tracking technology is better applied to investigate the particle transport distribution characteristics of CTBS tailings. Three concepts of particle accumulated gravity Ga, static friction angle θ and diameter dividing line are defined, and the transport pipe is divided into light wear zone, medium wear zone and heavy wear zone. The increase in pipe diameter increases the content of fine particles at the pipe wall and the thickness of the lubrication layer becomes larger, which improves the safety and stability of CTBS transport. The increased flow velocity reduces the settling phenomenon of large size particles and improves the transport efficiency, which increases the pipeline transport resistance. Under good tailings grading conditions, a wide range of tailings grading is more suitable as backfill material. The results of the study illustrate the flow characteristics of the backfill slurry in the pipeline from the particle perspective and provide a theoretical basis for pipeline transportation research. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Near infrared light organic photodetectors have attracted tremendous attention due to their tailorable response, ease of processing, compatibility with flexible substrate, room temperature operation and broad applications such as remote sensing, health monitoring, artificial vision, night vision, and so on. Recently, the great improvement obtained on the important figures of merit performances has made organic photodetectors catch up and even surpass those of inorganic photodetectors in some respects. In this review, after a brief illustration of the organic photodetectors' figures of merit performances, we summarize the research progress of panchromatic and narrowband near infrared light organic photodetectors from their working mechanism, strategies to achieve narrowband near infrared light organic photodetectors, to some practical applications. Finally, we discuss the development challenge of the near infrared light organic photodetectors. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Near infrared light organic photodetectors have attracted tremendous attention due to their tailorable response, ease of processing, compatibility with flexible substrate, room temperature operation and broad applications such as remote sensing, health monitoring, artificial vision, night vision, and so on. Recently, the great improvement obtained on the important figures of merit performances has made organic photodetectors catch up and even surpass those of inorganic photodetectors in some respects. In this review, after a brief illustration of the organic photodetectors' figures of merit performances, we summarize the research progress of panchromatic and narrowband near infrared light organic photodetectors from their working mechanism, strategies to achieve narrowband near infrared light organic photodetectors, to some practical applications. Finally, we discuss the development challenge of the near infrared light organic photodetectors. [ABSTRACT FROM AUTHOR]

Highly efficient and eco‐friendly antimicrobial agents are crucial to the development of future marine antifouling coatings. A high efficient and low bio‐toxicity bio‐based anti‐biofoulant, 2,5‐diformylfuran dioxime chelating with copper ions (E‐DFFD‐Cu), is evaluated. Its minimal bactericidal concentration and the concentration for 50% of maximal effect (EC50) are 4.95 and 7.03 µmol L−1, respectively. Excellent anti‐biofouling performance in marine environment in situ can be kept at least 90 days and with maximum release rate of copper ion of 0.01 µmol cm−2 d−1. Alkyl radical (R·) and hydrogen radical (H·) derived from E‐DFFD are enhanced via chelating copper(II) catalysis, which attracts and disrupts microbe cell membrane and pili between intimate cells, resulting in excellent anti‐biofouling effect. This provides a new perspective for developing anti‐biofoulant from anti‐biofouling mechanism in the future. [ABSTRACT FROM AUTHOR]

Investigating the effects of surrounding microenvironments and substituents on the excited‐state proton transfer (ESPT) mechanism have always been a great challenge, especially in protic solvents and solid state. In this work, a detailed theoretical study on ESPT processes of salicylic acid (SA) and its two derivatives (5ASA and 5NSA) in gas, cyclohexane, acetonitrile, ethanol (EtOH), and crystal phases is performed based on the density functional theory (DFT) and time‐dependent DFT as well as the combined quantum mechanics/molecular mechanics (QM/MM) methods. Intramolecular charge transfer‐induced aggregation‐caused quenching phenomenon of 5ASA is unveiled utilizing the hole–electron analysis. Independent gradient model analysis is implemented to reveal the spontaneous forward proton transfer (PT) behavior of 5ASA. Besides, potential energy surfaces are constructed to evaluate the dominant PT pathway in EtOH, and the related transition state structures are also obtained to accurately provide the intra‐ and inter‐PT energy barriers. Eventually, excited‐state ab initio molecular dynamics computation reaffirms that the intra‐PT reaction is predominant for SA. This theoretical work comprehensively explores the ESPT mechanism and luminescent properties of SA and its two derivatives, which provides a reference for developing efficient organic light‐emitting materials based on ESPT chromophores. [ABSTRACT FROM AUTHOR]

In organic solar cells (OSCs), the lower dielectric constant of organic semiconductor material induces a strong Coulomb attraction between electron–hole pairs, which leads to a low exciton separation efficiency, especially the charge transfer (CT) state. The CT state formed at the electron‐donor (D) and electron‐acceptor (A) interface is regarded as an unfavorable property of organic photovoltaic devices. Since the OSC works in a nonzero temperature condition, the entropy effect would be one of the main reasons to overcome the Coulomb energy barrier and must be taken into account. In this review, the present understanding of the entropy‐driven charge separation is reviewed and how factors such as the dimensionality of the organic semiconductor, energy disorder effect, the morphology of the active layer, are described, as well as how the nonequilibrium effect affects the entropy contribution in compensating the Coulomb dissociation barrier for CT exciton separation and charge generation process. The investigation of the entropy effect on exciton dissociation mechanism from both theoretical and experimental aspects is focused on, which provides pathways for understanding the underlying mechanisms of exciton separation and further enhancing the efficiency of OSCs. [ABSTRACT FROM AUTHOR]

As the largest component of carbon export from terrestrial ecosystems, ecosystem respiration (RECO), together with vegetation productivity, determines the carbon stock changes in terrestrial ecosystems, so it is crucial to reveal the response of RECO to climate change. However, the simulation of RECO is usually inaccurate due to the neglect of the lagged response of respiration to changes in water conditions. In this study, we integrated meteorological data, remote sensing data, and soil data, and introduced the indicators of the previous water conditions into the deep learning model to simulate RECO. The conclusions are as follows: (a) There is a 1–2 years' lagged response of RECO to changes in water conditions. (b) It is necessary to consider the influence of previous water conditions when simulate RECO. It not only improved the simulation accuracy of RECO, but also reflected its inter‐annual fluctuations and change trends more accurately, avoiding the underestimation of RECO inter‐annual fluctuations. (c) There is an inconsistency in carbon input and carbon output change trends which impacts the carbon sink pattern and potential of terrestrial ecosystems. The growth trend of Gross Primary Production (GPP) in global terrestrial ecosystems is greater than that of RECO, with a trend of increasing carbon sinks, especially in the northern extra‐tropics; while the carbon sink capacity of tropical regions has gradually saturated, showing that the change trend of RECO is close to that of GPP, which poses a potential risk to the sustainable carbon sink capacity of global ecosystems in the future. Plain Language Summary: Ecosystem respiration (RECO) is the largest component of carbon export from terrestrial ecosystems and determines the carbon sink potential of terrestrial ecosystems. Consider from the perspective of carbon cycle mechanism, it is reasonable to believe that RECO has the lagged response to changes in water conditions. However, most studies usually consider the water conditions in growing season only, which caused the inaccurate RECO simulations and underestimation of RECO's interannual variation. In this study, we introduced the multi‐time scale standardized precipitation evapotranspiration indexes‐which can reflect the current and previous water conditions‐into deep learning models to construct an optimal model for simulating global‐scale RECO. We revealed the optimal time scales of the lagged effect that need to be considered in RECO simulations and analyzed the global pattern of RECO tendencies and its implications on terrestrial carbon sink potential. We believe this paper to be of particular interest to the readers of your journal as our method is novel that could well reveal the spatial pattern and the interannual variations of RECO at global scale and our results have important implications for the assessment of terrestrial ecosystem carbon sink. In addition, it revealed some new rules that are interesting for the academic community. Key Points: There is a 1–2 years' lagged response of ecosystem respiration (RECO) to changes in water conditionsConsidering the previous water conditions can improve the simulation accuracy of RECO and its inter‐annual fluctuationsThere is an inconsistency in carbon input and carbon output change trends which impacts the carbon sink potential of terrestrial ecosystems [ABSTRACT FROM AUTHOR]

High‐performance organic semiconductor materials as the electroactive components of optoelectronic devices have attracted much attention and made them ideal candidates for solution‐processable, large‐area, and low‐cost flexible electronics. Especially, organic field‐effect transistors (OFETs) based on conjugated semiconductor materials have experienced stunning progress in device performance. To make these materials economically viable, comprehensive knowledge of charge transport mechanisms is required. The alignment of organic conjugated molecules in the active layer is vital to charge transport properties of devices. The present review highlights the recent progress of processing‐structure‐transport correlations that allow the precise and uniform alignment of organic conjugated molecules over large areas for multiple electronic applications, including OFETs, organic thermoelectric devices (OTEs), and organic phototransistors (OPTs). Different strategies for regulating crystallinity and macroscopic orientation of conjugated molecules are introduced to correlate the molecular packing, the device performance, and charge transport anisotropy in multiple organic electronic devices. [ABSTRACT FROM AUTHOR]

A flexible strain sensor with excellent mechanical and electrical properties was fabricated by depositing carboxylated multiwalled carbon nanotubes (CNTs) and graphene (Gr) onto thermoplastic polyurethane (TPU) nanofibrous membranes. The deposition efficiency and fastness of CNTs and Gr particles on TPU nanofibrous membranes were improved by vacuum assisted deposition and ultrasonication. Furthermore, a flexible strain sensor with excellent sensing performance was obtained by optimizing the optimal hybrid ratio between CNTs and Gr. Electromechanical experiments showed that the strain sensor had a wide working range of 172% with a high‐gauge factor of approximately 217 for TPU/5CNTs5Gr composite. Moreover, the TPU/5CNTs5Gr composite also exhibited good durability in 10,000 tensile loading‐unloading cycles, and had superior sensing performance when monitoring the bending motions of human finger, elbow and knee. [ABSTRACT FROM AUTHOR]

Spatiotemporal patterns of water stress caused by global warming has significantly affected gross primary productivity (GPP). However, its impact is hard to capture as the water stress of different timescales simultaneously influence GPP through the effects of time lag and legacy. As a result, synthetically considering the roles of water stress in the current year and previous years in GPP is very important for accurate modeling of GPP. In this study, we introduced the water stress indicators of standardized precipitation evapotranspiration index (SPEI) at different timescales, GPP observations from global flux network and the remote sensing‐based indexes to models of convolutional neural network (CNN). We built the optimal CNN model which effectively simulated the spatial patterns of GPP and detected their trends in interannual variation. The findings were as follows: (1) The CNN model with introduction of multi‐timescale SPEIs that reflect both current and previous years' water conditions improved the accuracy of modeled GPP. This result indicated that although GPP is most sensitive to current water conditions, it is also clearly affected by previous years' water conditions. (2) The optimal CNN model that considered previous years' water conditions not only aptly simulated the spatial distribution of GPP, but also showed advantages in simulating the interannual fluctuations of GPP and its response to drought. Ignoring the previous water conditions will underestimate the interannual fluctuations of GPP and the impact of drought on GPP. [ABSTRACT FROM AUTHOR]

Ternary architecture is a promising strategy to further boost the performance of organic solar cells (OSCs). Reducing the bandgap of the active layer materials not only widens the absorption wavelength range and enhances the short‐circuit current (Jsc) of the OSC, but also decreases the open‐circuit voltage (Voc) of the device, leading to a trade‐off situation for the optimization of the material system. Herein, a small‐molecule donor BTID‐2F, featuring a narrower bandgap than that of PM6, is introduced into a PM6:Y6 based system. The redshift in external quantum efficiency indicates the narrower bandgap and better aggregation in the ternary blends than those of binary ones. Interestingly, lower energy disorder and energy loss are also attained for the ternary devices, leading to higher Voc. Furthermore, owing to the suppressed recombination and morphological optimization, a simultaneous enhancement in the Jsc and fill factor boosts the power conversion efficiency (PCE) of ternary OSC to 17.9% compared to 16.62% for the binary device. Likewise, replacing the acceptor with the L8‐BO molecule further improves the ternary PCE to 18.52%. This work indicates an emerging approach for fabricating high‐performance ternary OSCs with a decreased bandgap and increased Voc. [ABSTRACT FROM AUTHOR]

The crystal orientation of small molecules is one of the key parameters for developing high‐performance small molecule based organic field‐effect transistors. However, achieving a high degree of backbone alignment still remains a challenge, due to the sensitive nature of small molecules to processing conditions. Herein, the thin films of three conjugated small molecules, named as ZR1, ZR2‐C3, and Y6 are prepared by epitaxial‐crystallization on a highly oriented polyethylene (PE) substrate, resulting in the significant enhancement in charge transport properties. The maximum mobilities for aligned edge‐on molecules in the films enhance by up to 9.91 × 10−2 and 8.97 × 10−2 cm2 V−1s−1 for ZR1 and ZR2‐C3 films with conducting channel along small molecule backbones, which are 35‐ and 37‐fold that of the values evaluated in perpendicular to molecular backbones and nearly 23‐and 19‐fold beyond the values measured from unaligned films. Furthermore, the electron and hole mobilities of the small molecule Y6 with face‐on nature increase by nearly fourfold the values measured in perpendicular to the backbone direction and from unaligned films. This work demonstrates the epitaxial crystallization of thin films on oriented PE, offers a critical understanding of small molecules with different orientations and an effective approach for tuning charge transport toward high‐performance organic electronic applications. [ABSTRACT FROM AUTHOR]

Akt signaling has been associated with adult neurogenesis in the hippocampal dentate gyrus (DG). We reported cognitive dysfunction in Akt3 knockout (Akt3‐KO) mice with the down‐regulation of mTOR activation. However, little is known about the effects of Akt3 signaling on hippocampal neurogenesis. Herein, we show that progenitor cells, neuroblasts, and mature newborn neurons in hippocampal DG expressed Akt3 protein. The Akt3 phosphorylation in hippocampal DG was increased after voluntary wheel running for 7 days in wild‐type mice (running WT mice), but not in Akt3‐KO mice (running Akt3‐KO mice). Subsequently, we observed that the proliferation of progenitor cells was suppressed in Akt3‐KO mice and the mTOR inhibitor rapamycin‐treated mice, whereas enhanced in running WT mice rather than running Akt3‐KO mice. Neurite growth of neuroblasts was impaired in Akt3‐KO mice and rapamycin‐treated mice. In contrast, neither differentiation of progenitor cells nor migrating of newly generated neurons was altered in Akt3‐KO mice or running WT mice. The levels of p70S6K and 4EBP1 phosphorylation were declined in Akt3‐KO mice and elevated in running WT mice depending on mTOR activation. Furthermore, telomerase activity, telomere length, and expression of telomerase reverse transcriptase (TERT) were decreased in Akt3‐KO mice but increased in running WT mice rather than running Akt3‐KO mice, which required the mTOR activation. The study provides in vivo evidence that Akt3‐mTOR signaling plays an important role in the proliferation of progenitor cells and neurite growth through positive regulated TERT expression and activation of p70S6K and 4EBP1. [ABSTRACT FROM AUTHOR]

For reconstructive surgeons, critically skeletal damage represents a major challenge. Growing evidence indicate that bone repair is dynamically regulated by the mesenchymal stem cell (MSC)‐macrophage interaction. Mechanical strain plays a fundamental role in bone repair and regeneration by influencing MSCs differentiation. Recently, a few findings indicate that macrophages may be mechanically sensitive and their phenotype can be regulated, in part, by mechanical cues. However, how macrophages subjected mechanical stretch influence the osteogenic differentiation of MSCs remain unclear. Thus, the purpose of this study is to explore the effect of macrophages stimulated with mechanical stretch on MSCs osteogenesis. By using a coculture system, we discover that macrophages efficiently induce osteogenic differentiation of MSCs under specific stretch conditions. A synergy mechanism between M2 polarization and YAP/BMP2 axis are identified through molecular and genetic analyses. Macrophages are activated by cyclic stretch and polarized to M2 phenotype that produce anti‐inflammatory cytokines such as IL‐10 and TGF‐β to regulate the local inflammatory microenvironment. Furthermore, mechanical stretch induces YAP activation and nuclear translocation, subsequently regulates downstream BMP2 expression to facilitate MSCs osteogenesis. These findings not only advance our understanding of the complex influence among the mechanical strain, macrophage inflammatory response as well as the osteogenic differentiation of MSCs, but also reveal a control system from mechanical signals to chemical response then to cell behaviors during bone repair and regeneration. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: The on‐demand building copolymer structures, from sequence to architecture, is crucial in understanding the relation between polymer structure and property, meanwhile motivating the innovation of polymer hierarchy. However, the challenge is conspicuous for complicated polymer structures from inherently intricate polymerization. In this work, copolymers with tailored grafting density and distributions were achieved using successive latent monomer and grafting‐from strategies. The hydroxyl group functionalized furan/maleimide adduct (FMOH) was selected as the latent monomer for RAFT polymerization of an array of copolymers with tailored localization of hydroxyl group along the main chain. The hydroxyl group further initiated the ring opening polymerization (ROP) of L‐lactide or ε‐caprolactone, resulting in a library of multicomponent copolymers via grafting‐from strategy. The initiating efficiency reached to ~100% with variable molecular weight (21300—58600 Da) and narrow distributions (ÐM < 1.25), indicating that such graft copolymers possessed controlled density and distribution of side chains as its linear template. The investigation on thermal properties of the well‐defined graft copolymers implied that the precise tailoring over copolymer structures at the molecule level could lead to tunable chemical/physical properties. This work bridged polymer from sequence to architecture, unveiled a new method in creating graft copolymers with programmable structures and provided the insight into the structure/property relationship. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: The on‐demand building copolymer structures, from sequence to architecture, is crucial in understanding the relation between polymer structure and property, meanwhile motivating the innovation of polymer hierarchy. However, the challenge is conspicuous for complicated polymer structures from inherently intricate polymerization. In this work, copolymers with tailored grafting density and distributions were achieved using successive latent monomer and grafting‐from strategies. The hydroxyl group functionalized furan/maleimide adduct (FMOH) was selected as the latent monomer for RAFT polymerization of an array of copolymers with tailored localization of hydroxyl group along the main chain. The hydroxyl group further initiated the ring opening polymerization (ROP) of L‐lactide or ε‐caprolactone, resulting in a library of multicomponent copolymers via grafting‐from strategy. The initiating efficiency reached to ~100% with variable molecular weight (21300—58600 Da) and narrow distributions (ÐM < 1.25), indicating that such graft copolymers possessed controlled density and distribution of side chains as its linear template. The investigation on thermal properties of the well‐defined graft copolymers implied that the precise tailoring over copolymer structures at the molecule level could lead to tunable chemical/physical properties. This work bridged polymer from sequence to architecture, unveiled a new method in creating graft copolymers with programmable structures and provided the insight into the structure/property relationship. [ABSTRACT FROM AUTHOR]

Agronomy journals form a core part of the process of scholarly communication and scientific research in the agronomic field. Determining the key features of high‐impact agronomic journals will be a central component for identifying the disciplinary development in the field of agronomy. In this study, we conducted a bibliometric study to fill this knowledge gap based on 64,703 articles published in 18 main agronomy journals since 1948 derived from the Scopus database. Our main findings were that (a) over 20% of publications in Advances in Agronomy and Agricultural and Forest Meteorology received more than 50 citations; (b) authors from the United States, China, the United Kingdom, Germany, and Australia published the most articles in these journals, comprising 22.4, 11.5, 10.7, 8.7, and 8.0% of the total number of publications, respectively; and (c) journals published in a given country had a greater number of papers published by authors of that country than by authors of other countries. Furthermore, three clusters for these 18 journals were identified that included the topics of agronomy, interactions between agronomy and soil sciences, and interactions between agronomy and plant sciences. The results of this study provide valuable insights regarding the current state of and future development trends in agronomic journals. [ABSTRACT FROM AUTHOR]

Potassium (K) cations are spontaneously formed upon thermal deposition of low‐coverage K onto an ultrathin CuO monolayer grown on Cu(110) and they were explored by low‐temperature scanning tunneling microscopy (STM) and X‐ray photoemission spectroscopy. The formed K cations are highly immobile and thermally stable. The local work function around an individual K cation decreases by 1.5±0.3 eV, and a charging zone underneath it is established within about 1.0 nm. The cationic and neutral states of the K atom are switchable upon application of an STM bias voltage pulse, which is simultaneously accompanied by an adsorption site relocation. [ABSTRACT FROM AUTHOR]

Dopaminergic (DAergic) neurons of the midbrain ventral tegmental area (VTA) are known to regulate the hypothalamic‐pituitary‐adrenal (HPA) axis but have no direct projections to the paraventricular nucleus (PVN) of the hypothalamus. This study investigated whether VTA DAergic afferents modulate glutamatergic transmission‐dependent GABAergic neurons in dorsolateral bed nucleus of stria terminalis (dlBNST) to affect the activity of the HPA‐axis. Herein, we demonstrate that systemic administration of the neurotoxicant 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) or the VTA‐injection of 1‐methyl‐4‐phenylpyridinium ion (MPP+) in male mice (MPTP‐mice and MPP+mice) caused a decline of tyrosine hydroxylase positive (TH+) cells in VTA with a reduction in TH+fibers in the dlBNST. MPTP‐mice and MPP+mice displayed a clear increase in serum levels of corticosterone (CORT) and adrenocorticotropic hormone, corticotropin‐releasing hormone (CRH) expression, and CRH neuron activity in PVN. The presynaptic glutamate release, glutamatergic synaptic transmission and induction of long‐term potentiation in dlBNST of MPTP‐mice were suppressed, and these effects were rescued by a D1‐like DAergic receptor (D1R) agonist and mimicked in control dlBNST by blockade of D1R. MPTP‐mice exhibited low expression of glutamic acid decarboxylase and dysfunction of the excitatory‐dependent GABAergic circuit in dlBNST, and these effects were recovered by the administration of D1R agonist. Furthermore, either dlBNST‐injection of D1R agonist or PVN‐injection of GABAA receptor (GABAAR) agonist could correct the increased secretion and expression of CRH in MPTP‐mice. The results indicate that the DAergic afferents from VTA enhance excitatory‐dependent activation of GABAergic neurons in dlBNST, which suppress the activity of the HPA‐axis. [ABSTRACT FROM AUTHOR]

Key points: Goal‐directed arm movements can be adjusted at short latency to target shifts.We tested whether similar adjustments are present during walking on a treadmill with shifting stepping targets.Participants responded at short latency with an adequate gain to small shifts of the stepping targets.Movements of the feet during walking are controlled in a similar way to goal‐directed arm movements if balance is not violated. It is well‐known that goal‐directed hand movements can be adjusted to small changes in target location with a latency of about 100 ms. We tested whether people make similar fast adjustments when a target location for foot placement changes slightly as they walk over a flat surface. Participants walked at 3 km/h on a treadmill on which stepping stones were projected. The stones were 50 cm apart in the walking direction. Every 5–8 steps, a stepping stone was unexpectedly displaced by 2.5 cm in the medio‐lateral direction. The displacement took place during the first half of the swing phase. We found fast adjustments of the foot trajectory, with a latency of about 155 ms, initiated by changes in muscle activation 123 ms after the perturbation. The responses corrected for about 80% of the perturbation. We conclude that goal‐directed movements of the foot are controlled in a similar way to those of the hand, thus also giving very fast adjustments. Key points: Goal‐directed arm movements can be adjusted at short latency to target shifts.We tested whether similar adjustments are present during walking on a treadmill with shifting stepping targets.Participants responded at short latency with an adequate gain to small shifts of the stepping targets.Movements of the feet during walking are controlled in a similar way to goal‐directed arm movements if balance is not violated. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA) is widely used in household applications. High‐dose exposure to PFOA has been associated with increased risks of infertility and premature ovarian insufficiency in woman. PFOA can alter hepatic gene expression by activating peroxisome proliferator‐activated receptor α (PPARα). The present study investigated whether exposure to PFOA via PPARα activation alters the synthesis of hepatic fibroblast growth factor 21 (FGF21) to disturb female neuroendocrine and reproductive function. In the present study, we show that the oral administration of PFOA (2 or 5 mg kg‐1) in adult female mice (PFOA mice) caused prolonged dioestrous, a reduction in the number of corpora lutea and decreased levels of hypothalamic gonadotrophin‐releasing hormone, serum progesterone and luteinising hormone (LH). Exposure to PFOA decreased the expression of vasopressin in the suprachiasmatic nucleus (SCN) and kisspeptin in the anteroventral periventricular nucleus (AVPV) with deficits in preovulation or oestrogen‐induced LH surge. PFOA via activation of PPARα increased dose‐dependently hepatic FGF21 expression, leading to elevated serum and hypothalamic FGF21 concentrations. Treatment of PFOA mice with the PPARα antagonist GW6471 or the FGF21 inhibitor PD173074 rescued SCN vasopressin and AVPV‐kisspeptin expression. Either administration of GW6471 and PD173074 or treatment with vasopressin and the G protein coupled receptor 54 agonist kisspeptin‐10 in PFOA‐mice was able to recover the regular oestrous cycle, ovulation ability, LH surge production and reproductive hormone levels. The present study provides in vivo evidence that exposure to PFOA (≥2 mg kg‐1) in mice causes down‐regulation of the kisspeptin‐reproductive endocrine system by enhancing PPARα‐mediated hepatic FGF21 expression. The liver‐brain reproductive endocrine disorder caused by PFOA exposure may lead to prolonged dioestrous and ovulation failure. [ABSTRACT FROM AUTHOR]

An important challenge facing rice production in China is to solve the problem of declining freshwater supply without affecting grain yield and quality. The purpose of this study was to investigate the effects of cultivation methods on the grain‐filling and chalk grains of Zhonghan 3 (Japonica) upland rice and Wuxiangjing 99–8 (Japonica) paddy rice. Both cultivars were cultivated in fields under three cultivation methods: continuous flooding (CF) as a control, bare dry cultivation (BC), and plastic film mulching dry cultivation (PFMC). Compared with CF, the yield of the upland rice decreased significantly, and the yield of paddy rice did not differ significantly under PFMC. The yields of both cultivars decreased significantly under BC. Superior and inferior grains of the two cultivars under PFMC had a greater mean grain‐filling rate (G) and a shorter active grain‐filling time (D). Under PFMC, the two cultivars had a higher export translocation rate of the matter from the stem and sheath and a slower decrease of the chlorophyll content in the flag leaves and nitrogen content in the plants after heading. Upland rice had a higher grain weight, and paddy rice had a lower grain weight compared to CF. The chalkiness of the two cultivars was significantly lower under dry cultivation than under CF. The correlation analysis showed that the percentage of chalky grains was negatively correlated with G and positively correlated with D, indicating that dry cultivation could improve the grain‐filling rate and appearance quality of the two cultivars. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) require a bulk heterojunction of a donor and an acceptor for efficient charge generation, whereas other types of solar cells normally use the p‐i‐n device structure. Herein, a comparative investigation of the p‐i‐n‐structured OSCs is conducted based on single‐donor‐component BTID‐0F and the bulkheterojuction OSCs with different donor:acceptor blend ratios using BTID‐0F as the donor and PC71BM as the acceptor. The highest power conversion efficiency (PCE) of 1.61% is obtained for single‐donor‐based OSCs. The impact of PC71BM weight ratio in BTID‐0F:PC71BM‐based OSCs upon blend morphology, material energetics, photogenerated charge dynamic process, and photovoltaic device performance is investigated, and the highest PCE reaches 8.47%. Results indicate that even when the acceptor sites are highly diluted and the acceptor phase is discontinuous, electron transport can occur with a reasonable electron mobility. The PCE of 1.61% is the highest PCE reported for p‐i‐n structure OSCs based on a single‐donor component, which is helpful to understand the mechanism of charge generation in organic materials and thus obtainhigh‐efficient OSCs using the p‐i‐n structure. [ABSTRACT FROM AUTHOR]

Reactive signaling molecules participate in varieties of biochemical reactions, and methods to detect their mutual existence and crosstalk are in urgent demand. A benzothiadiazole‐based handle was designed to fluorescently respond to the co‐existence of H2S and H2O2 under pseudo‐physiological conditions on a basis of a thiyl‐radical‐mediated mechanism that accounts for the rapid and efficient domino‐like reaction processes. Then the handle motif was attached to a rhodamine moiety by means of an ethynylene linkage, and achieved a significant H2S–H2O2 mutual response in the mitochondria of living cells. Theoretical calculations supported that a through bond energy transfer mechanism contributes to the drastic fluorescence response. [ABSTRACT FROM AUTHOR]

Background: Annexin 1 (ANXA1) expression is associated with the malignant tumor phenotype, making it an attractive therapeutic target. However, little is known about the regulation of ANXA1 in non‐small cell lung cancer (NSCLC). Methods: We investigated the biological roles of ANXA1 in tumor growth, migration, and invasion, and explored the possibility of ANXA1 as a potential therapeutic target for the treatment of NSCLC. Results: Our findings revealed that ANXA1 enhanced nuclear factor (NF)‐κB activation in NSCLC cells by interaction with inhibitor of NF‐κB kinase complex subunit, IKKγ. We also found that NF‐κB could negatively regulate microRNA (miR)‐26a, and miR‐26a was regulated through the ANXA1–NF‐κB regulatory pathway. NF‐κB activation negatively regulated by miR‐26a was confirmed in NSCLC. Conclusion: Together, these results provide evidence of the mechanisms of the ANXA1–NF‐κB–miR‐26a regulatory pathway in the invasion and migration in NSCLC. [ABSTRACT FROM AUTHOR]

Abstract: Three novel copolymers based on zigzag naphthodithiophene (zNDT) with different aromatic rings as π bridges and different core side substitutions are designed and synthesized (PzNDT‐T‐1,3‐bis(4‐(2‐ethylhexyl)‐thiophen‐2‐yl)‐5,7‐bis(2‐ethylhexyl)benzo[1,2‐c:4,5‐c′]‐dithiophene‐4,8‐dione (BDD), PzNDT‐TT‐BDD, and PzNDTP‐T‐BDD, respectively). The 2D conjugation structure and molecular planarity of the polymers can be effectively altered through the modification of conjugated side chains and π‐bridges. These alterations contribute to the variation in energy levels, light absorption capacity, and morphology compatibility of the polymers. When blended with the nonfullerene acceptor (2,2′‐[(4,4,9,9‐tetrahexyl‐4,9‐dihydro‐sindaceno[1,2‐b:5,6‐b′]dithiophene‐2,7‐diyl)bis[methylidyne(3‐oxo‐1H‐indene‐2,1(3H)‐diylidene)]]bis‐propanedinitrile) (IDIC), PzNDT‐T‐BDD exhibits the highest power conversion efficiency (PCE) of 9.72% among the three polymers. This result can be attributed to its superior crystallinity and more obvious face‐on orientation in blending film. PzNDT‐TT‐BDD and PzNDTP‐T‐BDD present PCE values of 8.20% and 4.62%, respectively. The alteration of polymer structure, particularly the modification of conjugated side chains and π‐bridges, is an effective strategy for designing NDT‐based polymers with high photovoltaic performance and potential applications in fullerene‐free solar cells. [ABSTRACT FROM AUTHOR]

ABSTRACT: Two novel bio‐based diamines are synthesized through introduction of renewable 2,5‐furandicarboxylic acid (2,5‐FDCA), and the corresponding aromatic polyimides (PIs) are then prepared by these diamines with commercially available aromatic dianhydrides via two‐step polycondensation. The partially bio‐based PIs possess high glass transition temperatures (Tgs) in the range from 266 to 364 °C, high thermal stability of 5% weight loss temperatures (T5%s) over 420 °C in nitrogen and outstanding mechanical properties with tensile strengths of 79–138 MPa, tensile moduli of 2.5–5.4 GPa, and elongations at break of 3.0–12.3%. Some colorless PI films (PI‐1‐b and PI‐1‐c) with the transmittances at 450 nm over 85% are prepared. The overall properties of 2,5‐FDCA‐based PIs are comparable with petroleum‐based PI derived from isophthalic acid, displaying the potential for development of innovative bio‐based materials. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1058–1066 [ABSTRACT FROM AUTHOR]

Abstract: Acceptor–donor–acceptor (A–D–A) is an effective molecular design strategy for organic small molecules. In this work, we reported a simple A–D–A small molecule (TBDT‐2HT‐ID), with thiophene‐substituted benzodithiophene (TBDT) as a core, 1H‐indene‐1,3(2H)‐dione (ID) as end‐capped acceptor, and linked by the π‐bridge of 3,6‐dihexylthieno[3,2‐b]thiophene. UV and CV results showed that the molecule exhibited good absorption in the range of 300–700 nm but a very low HOMO energy level (−5.47 eV). Grazing incidence X‐ray diffraction (GIXRD) results demonstrate it has good crystallinity and adopts an edge‐on molecular packing, and consequently its hole mobility could reach 1×10−3 cm2 V‐1S−1. Based on PC71BM as acceptor, TBDT‐2HT‐ID had an excellent power conversion efficiency with 7.4 % without any post‐treatment, and a very high Voc of 1.07 V, which would be one of the highest Voc reported so far. [ABSTRACT FROM AUTHOR]

Abstract: Activated carbon (AC) has been widely used in the catalysis field because of its low cost, scalable production, high specific surface area, and abundant exposed edge. Because of the amorphous structure, traditional AC is unstable in presence of O2 at high temperature, which hinders the application of AC catalysts in oxidative dehydrogenation (ODH) of alkanes. Here, partially graphitic AC decorated with few‐layer graphene is facilely fabricated by simple high‐temperature calcination. The graphitic transformation significantly enhances the antioxidation property, long‐term stability of AC during the ODH reaction, and especially dramatically increases the graphitic edge areas in which the active ketonic carbonyl groups are selectively formed in ODH reactions. A high reactivity with 41.5 % selectivity and 13.2 % yield to C4 alkenes were obtained at 450 °C over the optimized catalyst, which is superior to all the previously reported carbon catalysts and shows a great potential for industrial application. [ABSTRACT FROM AUTHOR]

Abstract: Pt nanoparticles (NPs) immobilized on a core–shell hybrid carbon support allow the efficient direct dehydrogenation of n‐butane at low temperatures. The hybrid carbon support is composed of a nanodiamond core and a reinforced ultrathin graphene shell (ND@G), which improves the stability of the anchored Pt NPs against sintering under the reaction conditions. The as‐prepared Pt/ND@G catalyst demonstrates excellent catalytic performance (≈25 % conversion with >95 % selectivity toward olefins) at 450 °C for over 10 h as a result of strong metal–support interactions. The catalyst can also be fully regenerated by postoxidative thermal treatment. [ABSTRACT FROM AUTHOR]

One of the challenges to realize large-scale water splitting is the sluggish kinetics of the anode reaction. Nowadays, metal phosphates are widely used as high-efficiency catalysts for the oxygen evolution reaction (OER). In this work, we studied common phosphoric acid salts including orthophosphate, pyrophosphate, and tripolyphosphate in a bimetallic catalyst to explore the effect of the anion in phosphate-based OER electrocatalysts. Co−Fe-Pi, Co−Fe-Pyro, and Co−Fe-Pyro were successfully synthesized through a simple and convenient co-precipitation method. Among them, Co−Fe-Pyro exhibits the best electrocatalytic activity, with a low overpotential of 276 mV at a current density of 10 mA cm−2, a small Tafel slope of 32 mV dec−1, and a durable stability of about 90 % after 30000 s at 1.62 V vs. RHE in 1 M KOH. XRD reveals the amorphous structure of the materials and XPS confirms the formation of Co−Fe-Pyro. SEM and TEM present the nanosheets with a porous structure on the surface of Co−Fe-Pyro. The distribution and ratio of the elements in Co−Fe-Pyro are confirmed by using EDS and ICP-AES. Therefore, this work promotes a new thought regarding the anion structure in the phosphate-based electrocatalysts. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is one of the most common neurodegenerative diseases. Recent epidemiological studies suggest that echinacoside (ECH), a phenylethanoid glycoside found in Cistanche deserticola, has a protective effect against the development of PD. However, the detailed mechanisms of how ECH suppresses neuronal death have not been fully elucidated. In this study, we confirmed that ECH protects nigrostriatal neurons against 6-hydroxydopamine (6-OHDA)-induced endoplasmic reticulum stress (ERS) in vivo and in vitro. ECH rescued cell viability in damaged cells and decreased 6-OHDA-induced reactive oxygen species accumulation in vitro. It also rescued tyrosine hydroxylase and dopamine transporter expression in the striatum, and decreased α-synuclein aggregation following 6-OHDA treatment in vivo. The validated mechanism of ECH activity was the reduction in the 6-OHDA-induced accumulation of seipin (Berardinelli-Seip congenital lipodystrophy 2). Seipin has been shown to be a key molecule related to motor neuron disease and was tightly associated with ERS in a series of in vivo studies. ECH attenuated seipinopathy by promoting seipin degradation via ubiquitination. ERS was relieved by ECH through the Grp94/Bip-ATF4-CHOP signal pathway. [ABSTRACT FROM AUTHOR]

Bulk heterojunction (BHJ) morphologies are vital to the device performance of organic solar cells (OSCs), including phase separation in lateral and vertical directions. However, the morphology developed from the blend solution is not easily predicted and controlled, especially in the vertical direction, because the BHJ morphology is kinetically frozen during the rapid solvent evaporation process. Here, a simple approach to control BHJ morphologies with optimized phase distribution for small molecule:[6,6]-phenyl-C71-butyric acid methyl ester (PC71 BM) blends by enhancing the substrate temperature during the spin-coating process. Three molecules with various fluorine atoms in the end acceptor units are selected. The relationship among molecular structures, substrate temperature effects on the morphology, and device performances are symmetrically investigated. Low temperature induces a multiple-sublayer-like architecture with significantly varied distributions of composition, morphology, and localized state energy, while high processing temperature induces more uniform film. The short-circuit current, open-circuit voltage, and fill factor of the devices are tuned with synergic improvement of efficiency toward over 10% and 11% for conventional and inverted devices. This work reveals the origination of vertical phase segregation, and provides a facile strategy to optimize the hierarchical phase separation for enhancing the performance of OSCs. [ABSTRACT FROM AUTHOR]

Iron-cobalt phosphomolybdate (FeCoPM12) nanoparticles, which are highly efficient catalytic materials for the oxygen evolution reaction (OER), were fabricated through a coprecipitation route. Compared with iron-cobalt hydroxide and state-of-the-art RuO2 electrocatalysts, the as-prepared FeCoPM12 sample exhibited robust OER catalytic activity with a low overpotential of 258 mV at a current density of 10 mA cm−2 and a small Tafel slope of 33 mV dec−1. Moreover, the as-synthesized sample presented preferable stability and after 10 h at 1.52 V the current density degraded by merely 8.3 %. This is ascribed to the high electrochemical stability and small porous structure of FeCoPM12, which provide effective electron transmission and improve the catalytic performance for OER in alkaline media. [ABSTRACT FROM AUTHOR]