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Radiography imaging protocols focus on particular body regions, therefore producing images of great similarity and yielding recurrent anatomical structures across patients. Exploiting this structured information could potentially ease the detection of anomalies from radiography images. To this end, we propose a Simple Space-Aware Memory Matrix for In-painting and Detecting anomalies from radiography images (abbreviated as SimSID). We formulate anomaly detection as an image reconstruction task, consisting of a space-aware memory matrix and an in-painting block in the feature space. During the training, SimSID can taxonomize the ingrained anatomical structures into recurrent visual patterns, and in the inference, it can identify anomalies (unseen/modified visual patterns) from the test image. Our SimSID surpasses the state of the arts in unsupervised anomaly detection by +8.0%, +5.0%, and +9.9% AUC scores on ZhangLab, COVIDx, and CheXpert benchmark datasets, respectively.

High-entropy alloy (HEA) catalysts exhibit enhanced hydrogen evolution reaction (HER) activity in water electrolysis, yet the understanding of their structure and active sites in reaction environments remains unclear. Here, we systematically investigated the HER activity and stability of PtPdRhRuCu/C through a combination of electrochemical measurements, in situsynchrotron radiation X-ray absorption spectroscopy (XAS) at the Cu K-edge and Pt L3-edge, and density functional theory (DFT) calculations. Uniformly sized PtPdRhRuCu HEA nanoparticles were prepared viaa facile one-step solvothermal method. In situXAS results revealed that the HEA nanoparticles maintained metallic states and a disordered arrangement of the overall structure at hydrogen evolution potential, implying the absence of the separated phases. Relying on multi-metal active sites, PtPdRhRuCu/C demonstrated a remarkably low overpotential of 23.3 mV at 10 mA cm–2in alkaline HER, which is significantly lower than the overpotential observed in commercial Pt/C (50.3 mV), and achieving a mass activity 7.9 times that of Pt/C. DFT calculations show that the synergy of each metal site optimizes the dissociation energy barrier of water molecules. This study not only demonstrates the advancement of high-entropy alloys in electrocatalysis but also provides a comprehensive understanding of the structure-activity relationship of these unique catalysts through detailed characterizations. Our findings further contribute to the rational design and application of high-entropy alloy catalysts, specifically in HER.

With the rapid development of the Internet and digital technology, the traditional and single mass communication mode of the Chinese Culture and Tourism Shows industry is constantly being weakened, the new network communication channels have promoted the production and consumption mode of the virtuous circle of cultural and tourism performance dramas. The purpose of this study is to comprehensively understand the communication status and characteristics of China's cultural and tourism performing arts dramas in the Internet space, and provide a scientific basis for the sound development of China's cultural and tourism performing arts dramas. This paper takes as research objects 144 Chinese culture and tourism shows (CCTS) played across China from October 2020 to October 2021, adopts an approach that combines big data mining with text analysis and case study and analyzes the status quo of the online communication of CCTS based on the Integrated Marketing Communications theory, to serve as a reference for the communication strategy of CCTS. The problems concerning the integrated communication of CCTS include: videos on tourism produced by non-official entities are of low quality; the authenticity of the operators behind the accounts that upload CCTS videos is hard to identify; the scope of brand promotion is not paid sufficient attention by CCTS operators. The communication strategies thus proposed to fit in the era of online communication are as follows: from the perspective of the subject of media, importance shall be attached to the celebrity effect to empower the online communication of CCTS; from the perspective of the audience, individual accounts need to be further guided to become an essential part of online communication of CCTS; from the perspective of the content, CCTS should be made in series to create a brand linkage effect; from the perspective of communication channels, importance needs to be attached to how the communication characteristics of CCTS vary among different online platforms. The research method used in this study is essentially exploratory and descriptive, so current research cannot statistically evaluate the causal relationship between the online communicative index of different Chinese Culture and Tourism Shows and box office sales.

Let r⩾ 2 be an integer. The real number α∈ [0, 1) is a jump for rif there exists a constant c> 0 such that for any ϵ> 0 and any integer m⩾ r, there exists an integer n0(ϵ, m) satisfying any r-uniform graph with n⩾ n0(ϵ, m) vertices and density at least α+ ϵcontains a subgraph with mvertices and density at least α+ c. A result of Erdős and Simonovits (1966) and Erdős and Stone (1946) implies that every α∈ [0, 1) is a jump for r= 2. Erdős (1964) asked whether the same is true for r⩾ 3. Frankl and Rödl (1984) gave a negative answer by showing that 1−1ℓr−1is not a jump for rif r⩾ 3 and ℓ> 2r. After that, more non-jumps are found by using a method of Frankl and Rödl (1984). Motivated by an idea of Liu and Pikhurko (2023), in this paper, we show a method to construct maps f: [0, 1) → [0, 1) that preserve non-jumps, i.e., if αis a non-jump for rgiven by the method of Frankl and Rödl (1984), then f(α) is also a non-jump for r. We use these maps to study hypergraph Turán densities and answer a question posed by Grosu (2016).

The real-time segmentation results of side-scan sonar (SSS) images can realize the intelligent perception of autonomous underwater vehicles (AUVs). However, there remains a compelling challenge that the models trained with training data may not generalize well in practical applications due to the various marine conditions/working devices. This article proposes a real-time cross-domain segmentation adaptation scheme for SSS images based on adversarial training via min–max training to distribute SSS images in the output space and marginal distribution adaption to improve the segmentation performance by minimizing the measured distribution distance. To further enhance the adapted model, the multilayer feature discriminators are established to realize the fine-grained alignment. Experiments on the real-world SSS datasets demonstrate that our proposed model outperforms state-of-the-art methods and achieves the actual industrial application for AUV.

OSCA/TMEM63 channels are the largest known family of mechanosensitive channels1–3, playing critical roles in plant4–7and mammalian8,9mechanotransduction. Here we determined 44 cryogenic electron microscopy structures of OSCA/TMEM63 channels in different environments to investigate the molecular basis of OSCA/TMEM63 channel mechanosensitivity. In nanodiscs, we mimicked increased membrane tension and observed a dilated pore with membrane access in one of the OSCA1.2 subunits. In liposomes, we captured the fully open structure of OSCA1.2 in the inside-in orientation, in which the pore shows a large lateral opening to the membrane. Unusually for ion channels, structural, functional and computational evidence supports the existence of a ‘proteo-lipidic pore’ in which lipids act as a wall of the ion permeation pathway. In the less tension-sensitive homologue OSCA3.1, we identified an ‘interlocking’ lipid tightly bound in the central cleft, keeping the channel closed. Mutation of the lipid-coordinating residues induced OSCA3.1 activation, revealing a conserved open conformation of OSCA channels. Our structures provide a global picture of the OSCA channel gating cycle, uncover the importance of bound lipids and show that each subunit can open independently. This expands both our understanding of channel-mediated mechanotransduction and channel pore formation, with important mechanistic implications for the TMEM16 and TMC protein families.

Cultural symbols serve as one of the most direct and tangible representations of culture spreading, including for the dissemination of Chinese civilization. This study embarks on an exploratory analysis and comparison of the portrayal of these ‘Chinese cultural symbols’ by Chinese and international mainstream large language models. Our findings reveal that calligraphy, Confucian philosophy, the Forbidden City, Peking Opera, and the Great Wall constitute the top five Chinese cultural symbols that receive the most attention from large language models. However, the depiction of the “Chinese cultural landscape” by current large language models predominantly concentrates on elements of traditional humanities and social sciences, with a noticeable absence of China’s contemporary development and technological accomplishments. Concurrently, there are significant disparities in the representation of “Chinese cultural symbols” between domestic and international large language models. This includes issues such as the international models deficiency in providing a holistic portrayal of China’s Political Ideologies and Institutional Systems. In light of these findings, this study proposes strategic suggestions and recommendations for promoting exchanges and mutual learning among civilizations in the era of large language models.

Vasopressin V2receptors (V2R) are a promising drug target for autosomal dominant polycystic kidney disease (ADPKD). As previous research demonstrated that the residence time of V2R antagonists is critical to their efficacy in both ex vivo and in vivo models of ADPKD, we performed extensive structure–kinetic relationship (SKR) analyses on a series of benzodiazepine derivatives. We found that subtle structural modifications of the benzodiazepine derivatives dramatically changed their binding kinetics but not their affinity. Compound 18exhibited a residence time of 77 min, which was 7.7-fold longer than that of the reference compound tolvaptan (TVP). Accordingly, compound 18exhibited higher efficacy compared to TVP in an in vivo model of ADPKD. Overall, our study exemplifies a kinetics-directed medicinal chemistry effort for the development of efficacious V2R antagonists. We envision that this strategy may also have general applicability in other therapeutic areas.

High-entropy transition-metal oxides are potentially interesting cathode materials for lithium-ion batteries, among which high-entropy layered oxides are considered highly promising because there exist two-dimensional ion transport channels that may, in principle, enable fast ion transport. However, high-entropy layered oxides reported to date exhibit fast capacity fading in initial cycles and thus are hardly of any practical value. Here, we investigate the structural and property changes of a five-element layered oxide, LiNi0.2Co0.2Mn0.2Fe0.2Al0.2O2, using electrochemical and physical characterization techniques. It is revealed that the M3O4phase formed at the surface of LiNi0.2Co0.2Mn0.2Fe0.2Al0.2O2due to the migration of metal ions from octahedral sites of the transition-metal layer to tetrahedral 8a and octahedral sites of the lithium layer hinders the intercalation of lithium ion, which leads to the low initial Coulombic efficiency and fast decay of reversible capacity. This mechanism could be generally applicable to other high-entropy layered oxides with different elemental compositions.

O3-Type layered oxides are widely studied as cathodes for sodium-ion batteries (SIBs) due to their high theoretical capacities. However, their rate capability and durability are limited by tortuous Na+diffusion channels and complicated phase evolution during Na+extraction/insertion. Here we report our findings in unravelling the mechanism for dramatically enhancing the stability and rate capability of O3-NaNi0.5Mn0.5–xSbxO2(NaNMS) by substitutional Sb doping, which can alter the coordination environment and chemical bonds of the transition metal (TM) ions in the structure, resulting in a more stable structure with wider Na+transport channels. Furthermore, NaNMS nanoparticles are obtained by surface energy regulation during grain growth. The synergistic effect of Sb doping and nanostructuring greatly reduces the ionic migration energy barrier while increasing the reversibility of the structural evolution during repeated Na+extraction/insertion. An optimized NaNMS-1 electrode delivers a reversible capacity of 212.3 mAh g–1at 0.2 C and 74.5 mAh g–1at 50 C with minimal capacity loss after 100 cycles at a low temperature of −20 °C. Such electrochemical performance is superior to most of the reported layered oxide cathodes used in rechargeable SIBs.

ABSTRACTLake ice phenology (LIP) is an essential indicator of climate change and helps with understanding of the regional characteristics of climate change impacts. Ground observation records and remote sensing retrieval products of lake ice phenology are abundant for Europe, North America, and the Tibetan Plateau, but there is a lack of data for inner Eurasia. In this work, enhanced-resolution passive microwave satellite data (PMW) were used to investigate the Northern Hemisphere Lake Ice Phenology (PMW LIP). The Freeze Onset (FO), Complete Ice Cover (CIC), Melt Onset (MO), and Complete Ice Free (CIF) dates were derived for 753 lakes, including 409 lakes for which ice phenology retrievals were available for the period 1978 to 2020 and 344 lakes for which these were available for 2002 to 2020. Verification of the PMW LIP using ground records gave correlation coefficients of 0.93 and 0.84 for CIC and CIF, respectively, and the corresponding values of the RMSE were 11.84 and 10.07 days. The lake ice phenology in this dataset was significantly correlated (P<0.001) with that obtained from Moderate Resolution Imaging Spectroradiometer (MODIS) data – the average correlation coefficient was 0.90 and the average RMSE was 7.87 days. The minimum RMSE was 4.39 days for CIF. The PMW is not affected by the weather or the amount of sunlight and thus provides more reliable data about the freezing and thawing process information than MODIS observations. The PMW LIP dataset provides the basic freeze–thaw data that is required for research into lake ice and the impact of climate change in the cold regions of the Northern Hemisphere. The dataset is available at http://www.doi.org/10.11922/sciencedb.j00076.00081.

Real-time nowcasting is an assessment of current economic conditions from timely released economic series (such as monthly macroeconomic data) before the direct measure (such as quarterly GDP figure) is disseminated. Dynamic factor models (DFMs) are widely used in econometrics to bridge series with different frequencies and achieve a reduction in dimensionality. However, most of the research using DFMs often assumes the number of factors is known. A Bayesian approach is developed to identify the unknown number of factors and estimate the latent dynamic factors of DFMs accurately in a real-time nowcasting framework. The proposed method can deal with unbalanced data, which is typical of a real-time nowcasting analysis. Furthermore, the particle Gibbs with backward simulation algorithm is considered to obtain estimated stochastic volatility (SV) in monthly series efficiently. The validity of the method is demonstrated through simulation studies and an empirical study of nowcasting US’s quarterly GDP growth using monthly data series of several categories in the US market. Both the simulation and empirical studies indicate that the proposed Bayesian approach is a viable option to conduct real-time nowcasting for the US’s quarterly GDP.

High-entropy layered oxide (HEO) cathodes have become a focal point of research in sodium-ion batteries. Herein, we identify two guidelines that are vital for the design and fabrication of HEO O3-type cathodes: enhanced energy storage capacity and robust cathode architecture. To achieve these benchmarks, precise methods are required to adjust the energy levels of the transition metals and maintain ionic radius discrepancies within 15%. We have synthesized and examined various HEO O3-type cathode composites. Specifically, the O3-Na[FeCoNiTi]1/6Mn1/4Zn1/12O2(O3-FCNTMZ1/12) has demonstrated an impressive reversible capacity of 127.3 mAh g−1, with exceptional long-cycle stability and superb rate capabilities. Notably, the O3-FCNTMZ1/12cathode exhibits superior Na storage performance at low temperatures. At −20 °C, it maintains 109.6 and 91.1 mAh g−1at 0.1 and 1 C, respectively, with an impressive 88% capacity retention after 1000 cycles at 1 C. In situX-ray diffraction analysis reveals a subtle phase transition from O3 to P3, with only a 3% volume expansion. Moreover, ex situX-ray absorption spectroscopy confirms minimal fluctuation in the TM-O and TM-TM distances, remaining under 9.9%. These well-defined criteria offer a clear strategy for designing and developing the O3-FCNTMZ1/12cathode, facilitating high-performance sodium-ion batteries, especially for demanding low-temperature applications.

The development of low-cost and high-safety cathode materials is critically important to sodium-ion battery (Na-ion) research. Here we report a carbon nanotube (CNT)-percolating Na2Fe(SO4)2cathode (NFS-CNT) prepared via a rationally designed mechano-chemical method. The material synthesis mechanism is elucidated for the first time by in situ X-ray diffraction and thermogravimetric analysis. It is discovered that Na2Fe(SO4)·4H2O is formed as an intermediate phase during the mechano-chemical process, which is dehydrated to produce the Na2Fe(SO4)2cathode material upon a mild thermal treatment. The NFS-CNT composite cathode achieves an ultra-long cycle-life of over 13,000 cycles at 10 C at room temperature and over 6000 cycles at 55 °C, demonstrating its exceptional durability. The superior cycling performance is attributed to the small lattice change during Na-ion extraction/insertion and the percolating CNT network. Furthermore, the NFS/CNT cathode exhibits stable cycle performance in Na-ion full cells (93.4 % retention after 700 cycles) and a significantly lower heat release (∼ 229.2 J g−1) at the fully charged state compared to a wide range of Na-ion and Li-ion cathodes. materials. demonstrating its high thermal stability and safety. This work provides a promising path towards developing low-cost, high-performance Na-ion batteries.

Multiple ex-situ monitors were applied to investigate the role of Pt/Ti2C catalysts in accelerating the conversion of polysulfides at different states during discharge/charge process.

Multimetallic nanoparticles are an important class of catalysts with significant technological potential. In this work, trimetallic PtPdCu nanoparticles synthesized via a facile one-pot colloidal method were loaded on Al2O3. A two-step treatment, including ligand exchange and low-temperature annealing, was applied subsequently to remove the stabilizing ligands. We studied the effects of annealing temperature on the physicochemical properties of the supported PtPdCu nanoparticles and their catalytic activities for nitrobenzene hydrogenation. It is found that varying the annealing temperature of PtPdCu/Al2O3catalysts not only effectively removes the surfactant, but also modulates the metal–support interaction between the metal nanoparticles and the support in terms of coverage of Al2O3on metal nanoparticles, which further tunes the catalytic activity for nitrobenzene hydrogenation. The partially Al2O3-encapsulated PtPdCu exhibits better catalytic activity for hydrogenation of nitrobenzene to aniline over the fully Al2O3-encapsulated and surfactant-covered PtPdCu catalyst.

An all-small-molecule (ASM) ternary solar cell has been constructed by using a donor of H11 and two acceptors (IDIC and IDIC-4F) with similar backbone. The third component of IDIC plays an important role in optimizing the morphology and forming 3D charge pathways for high-efficiency charge transport and photovoltaic performance.

Supplemental Digital Content is available in the text.

Landfilling waste textiles causes a waste of resources. Copper is the main metal in waste textiles, and it is one of the widely used pyrolysis catalysts. This research investigated the role of copper during the pyrolysis process of waste cotton textiles, including the promoting effect on hydrogen generation and its immobilization in biochar. The pyrolysis experiment was conducted on waste pure cotton textiles impregnated with different concentrations of copper nitrate solutions. The experimental results showed that the addition of copper increased the hydrogen concentration by 121%, while the pyrolysis process reduced the copper leaching rate by 57.5%. Hydrogen concentration increased by 123% as the temperature increased, but the high temperature would affect the immobilization of copper. Hydrogen production and copper immobilization could be improved simultaneously around 700 ℃. The gas evolution was monitored by TG-MS and the biochar was characterized by XRD, FTIR, and XPS. The results indicated that the complexation of oxygen−containing functional groups and the generation of metallic copper decreased the leaching of copper, the heterostructure of copper on the surface of biochar catalyzed the secondary cleavage of organic fraction, increasing the production of hydrogen. The mechanism of hydrogen generation involved the decomposition of cellulose, the cleavage of organic macromolecules, and the secondary reaction of small molecule gases.

The dysregulated intracellular cAMP in the kidneys drives cystogenesis and progression in autosomal dominant polycystic kidney disease (ADPKD). Mounting evidence supports that vasopressin V2receptor (V2R) antagonism effectively reduces cAMP levels, validating this receptor as a therapeutic target. Tolvaptan, an FDA-approved V2R antagonist, shows limitations in its clinical efficacy for ADPKD treatment. Therefore, the pursuit of better-in-class V2R antagonists with an improved efficacy remains pressing. Herein, we synthesized a set of peptide V2R antagonists. Peptide 33exhibited a high binding affinity for the V2R (Ki= 6.1 ± 1.5 nM) and an extended residence time of 20 ± 1 min, 2-fold that of tolvaptan. This prolonged interaction translated into sustained suppression of cAMP production in washout experiments. Furthermore, peptide 33exhibited improved efficacies over tolvaptan in both ex vivo and in vivo models of ADPKD, underscoring its potential as a promising lead compound for the treatment of ADPKD.

Mechanosensitive channels sense mechanical forces in cell membranes and underlie many biological sensing processes1–3. However, how exactly they sense mechanical force remains under investigation4. The bacterial mechanosensitive channel of small conductance, MscS, is one of the most extensively studied mechanosensitive channels4–8, but how it is regulated by membrane tension remains unclear, even though the structures are known for its open and closed states9–11. Here we used cryo-electron microscopy to determine the structure of MscS in different membrane environments, including one that mimics a membrane under tension. We present the structures of MscS in the subconducting and desensitized states, and demonstrate that the conformation of MscS in a lipid bilayer in the open state is dynamic. Several associated lipids have distinct roles in MscS mechanosensation. Pore lipids are necessary to prevent ion conduction in the closed state. Gatekeeper lipids stabilize the closed conformation and dissociate with membrane tension, allowing the channel to open. Pocket lipids in a solvent-exposed pocket between subunits are pulled out under sustained tension, allowing the channel to transition to the subconducting state and then to the desensitized state. Our results provide a mechanistic underpinning and expand on the ‘force-from-lipids’ model for MscS mechanosensation4,11.

Light-mediated remote control of stem cell fate, such as proliferation, differentiation, and migration, can bring a significant impact on stem cell biology and regenerative medicine. Current UV/vis-mediated control approaches are limited in terms of nonspecific absorption, poor tissue penetration, and phototoxicity. Upconversion nanoparticle (UCNP)-based near-infrared (NIR)-mediated control systems have gained increasing attention for vast applications with minimal nonspecific absorption, good penetration depth, and minimal phototoxicity from NIR excitations. Specifically, 808 nm NIR-responsive upconversion nanomaterials have shown clear advantages for biomedical applications owing to diminished heating effects and better tissue penetration. Herein, a novel 808 nm NIR-mediated control method for stem cell differentiation has been developed using multishell UCNPs, which are optimized for upconverting 808 nm NIR light to UV emission. The locally generated UV emissions further toggle photoswitching polymer capping ligands to achieve spatiotemporally controlled small-molecule release. More specifically, with 808 nm NIR excitation, stem cell differentiation factors can be released to guide neural stem cell (NSC) differentiation in a highly controlled manner. Given the challenges in stem cell behavior control, the developed 808 nm NIR-responsive UCNP-based approach to control stem cell differentiation can represent a new tool for studying single-molecule roles in stem cell and developmental biology.

Although much is known about the interaction of fibrinogen with αIIbβ3, much less is known about the interaction of platelets with cross-linked fibrin. Fibrinogen residue Lys406 plays a vital role in the interaction of fibrinogen with αIIbβ3, but because it participates in fibrin cross-linking, it is not available for interacting with αIIbβ3. We studied the adhesion of platelets and HEK cells expressing normal and constitutively active αIIbβ3 to both immobilized fibrinogen and D-dimer, a proteolytic fragment of cross-linked fibrin, as well as platelet-mediated clot retraction. Nonactivated platelets and HEK cells expressing normal αIIbβ3 adhered to fibrinogen but not D-dimer, whereas activated platelets as well as HEK cells expressing activated αIIbβ3 both bound to D-dimer. Small-molecule antagonists of the αIIbβ3 RGD (Arg-Gly-Asp) binding pocket inhibited adhesion to D-dimer, and an Asp119Ala mutation that disrupts the β3 metal ion–dependent adhesion site inhibited αIIbβ3-mediated adhesion to D-dimer. D-dimer and a polyclonal antibody against D-dimer inhibited clot retraction. The monoclonal antibody (mAb) 10E5, directed at αIIb and a potent inhibitor of platelet interactions with fibrinogen, did not inhibit the interaction of activated platelets with D-dimer or clot retraction, whereas the mAb 7E3, directed at β3, inhibited both phenomena. We conclude that activated, but not nonactivated, αIIbβ3 mediates interactions between platelets and D-dimer, and by extrapolation, to cross-linked fibrin. Although the interaction of αIIbβ3 with D-dimer differs from that with fibrinogen, it probably involves contributions from regions on β3 that are close to, or that are affected by, changes in the RGD binding pocket.

Although much is known about the interaction of fibrinogen with αIIbβ3, much less is known about the interaction of platelets with cross-linked fibrin. Fibrinogen residue Lys406 plays a vital role in the interaction of fibrinogen with αIIbβ3, but because it participates in fibrin cross-linking, it is not available for interacting with αIIbβ3. We studied the adhesion of platelets and HEK cells expressing normal and constitutively active αIIbβ3 to both immobilized fibrinogen and D-dimer, a proteolytic fragment of cross-linked fibrin, as well as platelet-mediated clot retraction. Nonactivated platelets and HEK cells expressing normal αIIbβ3 adhered to fibrinogen but not D-dimer, whereas activated platelets as well as HEK cells expressing activated αIIbβ3 both bound to D-dimer. Small-molecule antagonists of the αIIbβ3 RGD (Arg-Gly-Asp) binding pocket inhibited adhesion to D-dimer, and an Asp119Ala mutation that disrupts the β3 metal ion–dependent adhesion site inhibited αIIbβ3-mediated adhesion to D-dimer. D-dimer and a polyclonal antibody against D-dimer inhibited clot retraction. The monoclonal antibody (mAb) 10E5, directed at αIIb and a potent inhibitor of platelet interactions with fibrinogen, did not inhibit the interaction of activated platelets with D-dimer or clot retraction, whereas the mAb 7E3, directed at β3, inhibited both phenomena. We conclude that activated, but not nonactivated, αIIbβ3 mediates interactions between platelets and D-dimer, and by extrapolation, to cross-linked fibrin. Although the interaction of αIIbβ3 with D-dimer differs from that with fibrinogen, it probably involves contributions from regions on β3 that are close to, or that are affected by, changes in the RGD binding pocket.

Supplemental Digital Content is available in the text.

ABSTRACTGround-level ozone concentration has demonstrated a noteworthy increasing trend in easternChina over the past 20 years, exerting inescapable influence on atmospheric chemistry, climate change, and air pollution. To support epidemiological research and prevent further environmental pollution, it is imperative to monitor the spatio-temporal distribution of ground-level ozone pollution. Geostationary satellites prove a promising approach to make up for the limitation of ground-based measurement and polar-orbiting observation by acquiring regional atmospheric measurements of high spatio-temporal resolution, yet inevitably exists spatial discontinuity caused by the cloud cover. This study established an effective model to produce spatially continuous estimation of hourly 5 km ground-level ozone (O3) concentrations covered most of China by firstly integrating hourly Himawari-8 SWR product from 1 March 2018 to 28 February 2019. The R2values of established model of all available samples for direct fitting, 20-fold cluster-based CV, 10-fold site-based CV, and 10-fold sample-based CV reaches 0.95, 0.69, 0.87 and 0.89, respectively, implying superior universality and spatial scalability. The R2values of seasonal site-based CV range from 0.78 (Winter) to 0.86 (Autumn), and that of hourly site-based CV ranges from 0.73 (0900 BST) to 0.86 (1300 BST). In addition, this study displayed the spatial distribution of the estimated ground-level ozone from the temporal scales of quarter, week, and day. Summer (87.1 ± 28.2 μg/m3) proves to be the most polluted season, and the least polluted season is winter (59.4 ± 16.1 μg/m3). 1400 BST appears to be the most polluted hour (87.4 ± 26.6 μg/m3) and 0900 BST is the least polluted hour (59.1 ± 16.8 μg/m3). Remarkable “weekend effect of ozone” has been detected in northeast Hebei and Sichuan Basin and Yangtze River valley.

Lithium‐ion batteries with spinel Li4Ti5O12materials as anode, which can offer fast charge times, high power output, superior safety, and long life, are considered to be a competitive choice for grid‐scale energy storage systems (ESS). Herein, a 10 Ah lithium–titanate battery with lithium cobalt oxide–lithium nickel cobalt manganese oxide dual‐phase cathode is developed and its application in 100 kWh‐level ESS is investigated. The 10 Ah single battery demonstrates a specific capacity of 79 Wh kg−1with a high‐capacity retention rate of 91.8% after 1000 cycles at 55 °C and >80% capacity retention at 15 Ccell. The 125 kWh ESS shows an energy efficiency of 97.82% and 89.97% at 0.2 and 1.5 CSystem, respectively. Self‐discharge and constant power tests indicate that the battery system is stable, thus suitable for storing intermittent power from renewable sources such as solar and wind. The system's ability of smoothing the fluctuated power is confirmed by coordinating with a wind power system. This work describes a kW‐leveling energy storage system assembled using lithium‐ion batteries with Li4Ti5O12as anode and LiCoO2/LiNixCoyMn1‐x−yO2as mixed cathode. It systematically investigates the electrochemical performances of the system and demonstrates that the system is stable and suitable for use with intermittent power sources such as wind power.

Herein, a practical Cu-catalyzed selenodifluoromethylation protocol was developed, using readily available diselenides as the selenium source under external-oxidant-free conditions. Various structurally diverse 4-seleno-substituted α,α-difluoro-γ-lactams were obtained in moderate to excellent yields. Easy scaleup and the potential for product derivatization make this method attractive for the preparation of other valuable fIuorinated γ-lactams. Mechanistic studies suggest that the catalytic system may involve a radical pathway.

Spinel Li4Ti5O12(LTO) has been considered as an anode for next generation lithium ion batteries. It has the advantages of negligible structural variation and high lithium intercalation plateaus. In addition, its negligible structural variation during lithium ion intercalation/deintercalation also provides a longer lifespan when applied as an anode. However, an inherently insulating property has currently limited its use in high-rate applications. Different from existing attempts, we demonstrate a facile method to improve the rate performance of Li4Ti5O12electrodes by introducing CFxduring the electrode preparation process. A series of Li4Ti5O12electrodes was fabricated with varied the additional ratio of CFxthat exhibited excellent rate performance even at a rate of 20 C. The best additive ratio was found to be 2.5% CFxby mass, which produced electrodes with a reversible capacity of 164 and 102 mAh g−1at the rates of 1 and 20 C, respectively.