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Here a base‐mediated formal [2+4] annulation of 3‐hydroxyoxindoles with 1,2‐bis(bromomethyl)benzene have been accomplished, affording spirooxindole‐fused oxacycles in good yields. This protocol features great functional group tolerance in mild reaction conditions. Gram‐scale synthesis and further transformation have also been demonstrated. [ABSTRACT FROM AUTHOR]

Odontogenic infections can spread to the respiratory tract. Despite the known role of Tannerella forsythia as the primary pathogen in periodontitis, the association between T. forsythia infection and risk of pneumonia or lung abscess remains unknown. In this report, we present a case of lung abscess caused by T. forsythia infection. The pathogen was detected by metagenomic next‐generation sequencing (mNGS) in the bronchoalveolar lavage fluid of the patient. The clinical characteristics and possible mechanisms of the infection are discussed. T. forsythia is a conditional pathogen that can cause lung abscess in the presence of helper bacteria and reduced host immune status. The course of treatment should be personalized and might be longer than 3 months. [ABSTRACT FROM AUTHOR]

In this article, a lightweight, untethered wearable adhesive glove (total weight 72 g) is developed to empower the human hand with adhesive gripping. A textile glove comprises ionogels with embedded flexible heaters and a wireless electronic control module. The thermoresponsive ionogel with switchable adhesion achieves a switching ratio of 4.9 after heating 4.4 s under 4 V voltage, enabling on‐demand object pickup and release. As demonstration examples, the wearable adhesive glove is shown to grasp multiple objects with single‐finger adhesion and manipulate card with two‐finger adhesion. It is shown in the experiments that the wearable adhesive glove can expand the gripping modes and enhance the gripping ability of the human hand by giving it a new degree of freedom of adhesion. [ABSTRACT FROM AUTHOR]

Light hydrocarbon (C2~C3) adsorption treatment in order to achieve exhaust emission standards of volatile organic compounds (VOCs) is very important and urgent in oil refining and oil storage enterprises. As an important adsorbent, metal‐organic frameworks (MOFs) with large specific surface area and good designability show excellent adsorption properties for light hydrocarbon. In this paper, by replacing the nitrate commonly used in the synthesis of MOFs with alkali metal, and adding a certain proportion of competing carboxylic acid into the reaction system, Cu‐BTC with improved pore structure and adsorption performance of light hydrocarbon was prepared at room temperature. More impressively, 10 L and 100 L scale‐up synthesis of Cu‐BTC were carried out by this method, which remained high light hydrocarbon adsorption capacities, showing great application prospect in the field of VOCs treatment. [ABSTRACT FROM AUTHOR]

To address the problems of traditional two‐level nested arrays (TTNA) with low degrees of freedom and high mutual coupling, a generalised two‐level nested MIMO radar array with high degrees of freedom and low mutual coupling for the direction of arrival (DOA) estimation is proposed. First, two coprime expansion factors are introduced in the TTNA to mitigate mutual coupling among array elements and enhance its degrees of freedom. Secondly, the range of consecutive lags and the total number of virtual array elements are derived in closed form under the structures of 'sum–difference co‐array'. Finally, utilising the atomic norm minimisation theory, the authors address the issue of discrete holes caused by different coprime expansion factors through filling in virtual arrays at discontinuities. Furthermore, a convex optimisation model to recover equivalent received signals from these filled virtual arrays is established, which is combined with a multiple signal classification algorithm for DOA estimation. Simulation results validate the rationality of the array structure and demonstrate the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

Photovoltaic technology with low weight, high specific power in cold environments, and compatibility with flexible fabrication is highly desired for near‐space vehicles and polar region applications. Herein, we demonstrate efficient low‐temperature flexible perovskite solar cells by improving the interfacial contact between electron‐transport layer (ETL) and perovskite layer. We find that the adsorbed oxygen active sites and oxygen vacancies of flexible tin oxide (SnO2) ETL layer can be effectively decreased by incorporating a trace amount of titanium tetrachloride (TiCl4). The effective defects elimination at the interfacial increases the electron mobility of flexible SnO2 layer, regulates band alignment at the perovskite/SnO2 interface, induces larger perovskite crystal growth, and improves charge collection efficiency in a complete solar cell. Correspondingly, the improved interfacial contact transforms into high‐performance solar cells under one‐sun illumination (AM 1.5G) with efficiencies up to 23.7 % at 218 K, which might open up a new era of application of this emerging flexible photovoltaic technology to low‐temperature environments such as near‐space and polar regions. [ABSTRACT FROM AUTHOR]

The development of metal‐halide perovskite nanocrystals (NCs) that yield bright and stable emission is of great importance. Previous reported perovskite NCs are mostly based on APbX3‐type family fabricated via ligand‐ or surfactant‐assisted chemical approaches. However, realizing bright and stable emission remains a challenge because of desorption of ligands/surfactants during long‐term operation. Herein, Ruddlesden–Popper (RP)‐type (A)2(MA)n‐1PbnBr3n+1 NCs with size less than Bohr radius stabilized in mesoporous silica scaffold, which are prepared in situ via physical approach at low temperature are introduced. The RP NCs in mesoporous silica exhibit the formation of spatially and electronically separated quantum wells, efficient energy funneling between different n phases for bright emission (photoluminescence quantum yields of ≈99%), high irradiation stability (T70 = 110 days), and long‐term stability (T90 = 110 days). These RP NCs have broad potential for bright light‐emitting diodes, high‐resolution PL imaging, and waterproof inks. Importantly, for the first time, stretchable perovskite X‐ray scintillator is demonstrated with excellent X‐ray imaging with resolution greater than 14 line pairs mm−1. These findings offer a paradigm to motivate future research toward stable and efficient perovskite optoelectronics. [ABSTRACT FROM AUTHOR]

A series of Cu−Mn−(La)−Zr catalysts with molecular ratios of 6 : 3 : (0.35) : 1 was synthesized by sol‐gel (CMLZ−S), co‐precipitation (CML−CP, CMLZ−CP) and hydrothermal (CMLZ−H) methods, respectively. The effects of the Mn and La on the activity of catalysts were investigated. It was found that the addition of La promoted the formation of the medium basic sites. Mn acted as an electronic promotor that transfer electrons through redox reactions, causing other metals to exhibit different valence states, thus promoting the adsorption and activation of H2 and CO2. At a certain temperature, methanol selectivity decreased in the order of CMLZ−H>CMLZ−S>CMLZ−CP>CMZ−CP. The selectivity of methanol is correlated with the distribution of basic sites. For the CMLZ−H catalyst, the highest percentage of moderate basic sites facilitated the activation of CO2, resulting in the highest selectivity of methanol. The CO2 conversion was correlated with the Cu specific surface area. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa L.) plants are most sensitive to chilling injury at booting, where cold affects a substantial decline in the seed‐setting rate (SSR). 6‐Benzyladenine (6‐BA) alleviates cold stress in seedlings; however, little is known about the effects of 6‐BA on alleviating cold stress at booting. Plants of early japonica rice cultivars Kenjiandao6 (K6) and Kongyu131 (K131) were sprayed with 6‐BA at concentrations of 0, 0.2, 2, 20, 200, and 500 mg L−1 at booting and were then subjected to cold water stress (16 °C) for 5 d. The optimal 6‐BA concentration was found to be 20 mg L−1. 6‐Benzyladenine treatment improved the peroxidase (POD) activity in two cultivars and superoxide dismutase activity in K6, delayed chlorophyll degradation, maintained the K, P, and N contents in the two cultivars and the soluble protein content in K6, and suppressed the accumulation of malondialdehyde (MDA) under cold stress. 6‐Benzyladenine increased the N and P contents and POD activity to greater degree in K6 than in K131. 6‐Benzyladenine increased yield in K131, mainly by improving the SSR in the distal and middle parts of the panicle, and the number of filled grains (NFG) from the middle and basal parts of the panicle. However, 6‐BA increased yield in K6 mainly by improving the SSR and the NFG per panicle. Exogenous 6‐BA is effective for maintaining rice physiology and yield under cold stress at booting. The less cold‐tolerant cultivar K6 was more sensitive to the effects of 6‐BA and displayed better results than did the more cold‐tolerant cultivar K131. Core Ideas: The optimal 6‐benzyladenine concentration was found to be 20 mg L−1 under cold stress in early japonica rice at booting.6‐Benzyladenine at 20 mg L−1 effectively reduced the physiological and metabolic damage in rice due to cold stress at booting.6‐Benzyladenine increased the cold resistance of 'Kongyu131' mainly by improving the peroxidase activity, chlorophyll, N, P, and K contents.6‐Benzyladenine enhanced a resistance of 'Kenjiandao6' mainly by improving superoxide dismutase and peroxidase activities, soluble protein, chlorophyll, N, P, and K content.The effect of 6‐benzyladenine was higher in the less cold tolerant variety Kenjiandao6 than in Kongyu131 under cold stress. [ABSTRACT FROM AUTHOR]

Hypericum perforatum is among the most commonly used herbal remedies and supplements. The aerial plant parts are often used to treat depression. Due to the lack of genomic information of H. perforatum, the gene networks regulating secondary metabolite synthesis remain unclear. Here, we present a high‐quality genome for H. perforatum with a 2.3‐Mb scaffold N50. The draft assembly covers 91.9% of the predicted genome and represents the fourth sequenced genus in the order Malpighiales. Comparing this sequence with model or related species revealed that Populus trichocarpa and Hevea brasiliensis could be grouped into one branch, while H. perforatum and Linum usitatissimum are grouped in another branch. Combined with transcriptome data, 40 key genes related to melatonin, hyperforin, and hypericin synthesis were screened and analyzed. Five N‐acetylserotonin O‐methyltransferases (HpASMT1‐HpASMT5) were cloned and functionally characterized. Purified HpASMT3 protein converted N‐acetylserotonin into melatonin with a Vmax of about 1.35 pkat/mg protein. HpASMT1 and HpASMT3 overexpression in Arabidopsis mutants caused 1.5‐2‐fold higher melatonin content than in mutant and wild‐type plants. The endogenous reactive oxygen species (ROS) in transgenic plants was significantly lower than ROS in mutant and wild‐type plants, suggesting higher drought tolerance. The obtained genomic data offer new resources for further study on the evolution of Hypericaceae family, but also provide a basis for further study of melatonin biosynthetic pathways in other plants. [ABSTRACT FROM AUTHOR]

Heterojunction engineering is a fundamental strategy to develop efficient electrocatalysts for the oxygen reduction reaction by tuning electronic properties through interfacial cooperation. In this study, a heterojunction electrocatalyst consisting of bimetallic carbide Co3ZnC and cobalt encapsulated within N‐doped carbon nanotubes (Co3ZnC/Co@NCNTs) is synthesized by a facile two‐step ion exchange‐thermolysis pathway. Co3ZnC/Co@NCNTs effectively promotes interfacial charge transport between the different components with optimizes adsorption and desorption of intermediate products at the heterointerface. In situ‐grown N‐doped carbon nanotubes (NCNTs) not only improve the electrical conductivity but also suppress the oxidation of transition metal nanoparticles in alkaline media. Moreover, the abundant nitrogen types (pyridinic N, Co−Nx, and graphitic nitrogen) in the carbon skeleton provide more active sites for oxygen adsorption. Benefitting from this optimized structure, Co3ZnC/Co@NCNTs hybrid not only demonstrates excellent oxygen reduction activity, with a half‐wave potential of 0.83 V and fast mass transport with limited current density of 6.23 mA cm−2, but also exhibits superior stability and methanol tolerance, which surpass those of commercial Pt/C catalysts. This work provides an effective heterostructure for interfacial electronic modulation to improve electrocatalytic performance. [ABSTRACT FROM AUTHOR]

The area of forest established through afforestation/reforestation has been increasing on a global scale, which is particularly important as these planted forests attenuate climate change by sequestering carbon. However, the determinants of soil organic carbon (SOC) sequestration and their contribution to the ecosystem carbon sink of planted forests remain uncertain. By using globally distributed data extracted from 154 peer‐reviewed publications and a total of 355 sampling points, we investigated above‐ground biomass carbon (ABC) sequestration and SOC sequestration across three different climatic zones (tropical, warm temperate, and cold temperate) through correlation analysis, regression models, and structural equation modeling (SEM). We found that the proportion of SOC sequestration in the ecosystem C sequestration averaged 14.1% globally, being the highest (27.0%) in the warm temperate and the lowest (10.7%) in the tropical climatic zones. The proportion was mainly affected by latitude. The sink rate of ABC (RABC) in tropical climates (2.48 Mg C ha−1 year−1) and the sink rate of SOC (RSOC) in warm temperate climates (0.96 Mg C ha−1 year−1) were higher than other climatic zones. The main determinants of RSOC were the number of frost‐free days, latitude, mean annual precipitation (MAP), and SOC density (SOCD) at the initial observation; however, these variables depended on the climatic zone. According to the SEM, frost‐free period, mean annual temperature (MAT) and MAP are the dominant driving factors affecting RSOC in Chinese plantations. MAT has a positive effect on RSOC, and global warming may increase RSOC of temperate plantations in China. Our findings highlight the determinants of SOC sequestration and quantitatively reveal the substantial global contribution of SOC sequestration to ecosystem carbon sink provided by planted forests. Our results help managers identify and control key factors to increase carbon sequestration in forest ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: To gain in‐depth insights into the relevant exposed crystal planes for the photocatalytic performance of perovskite‐structured oxides, SrSnO3 nanocrystals with different microstructures were synthesized and their photocatalytic activity for the degradation of simulated dye was investigated. The as‐obtained orthorhombic SrSnO3 nanorods with exposed {001} crystal planes showed higher photocatalytic activity for decomposing methylene blue than that of SrSnO3 nanoribbons with exposed {111} crystal planes. The surface atomic configurations revealed that the quantity of SnO2 overlayer on the {001} crystal facets is slightly greater than that on {111} crystal planes, which results in exposed {001} crystal facets of the SrSnO3 nanorods that can exhibit better activity in the photocatalytic process, due to fewer lattice defects, which act as traps for photogenerated charge carriers to decrease the recombination of photoexcited electrons and holes. This originated from narrowing of the crystal face distance and slight variation of the unit cell parameters; the crystallographic axis became shorter and the value of lattice strain became smaller. As a result, SrSnO3 nanocrystals exhibited different surface behavior under post‐treatment conditions and exhibited variation in the photocatalytic properties. The findings reported herein highlight the importance of probing the properties of surface facets in the evaluation of the photocatalytic performance of ternary metal oxides. [ABSTRACT FROM AUTHOR]

Abstract: Photoresponsive materials have tremendous potential applications in many fields. However, it is still a challenge to realize such materials, especially in isolated micro‐ or nanostructured form, with precisely controlled photomechanics for creating arbitrary deformations in a reversible way. Based on the coupling of photoinduced mass immigration with polymer networks, a general concept is proposed for producing nanostructured materials capable of reversibly creating arbitrary deformations. It is found for these type of materials the molecule alignment in the formation of a polymer network is not necessary to generate large anisotropic strain and stress. Importantly, the photoinduced mass immigration in a polymer network can provide unprecedented freedom in rapid exceptional spatiotemporal control over the molecule alignment profile and thus mechanical response within the network, enabling polymer formation of arbitrary deformations. Moreover, the inscribed molecule alignment profile is erasable and the fabricated materials can serve as a reconfigurable platform to present different mechanical behaviors. [ABSTRACT FROM AUTHOR]

A microfluidic assembly approach was developed for efficiently producing hydrogel spheres with reactive multidomains that can be employed as an advantageous platform to create spherical porous networks in a facile manner with well-defined multicompartments and spatiotemporally controlled functions. This strategy allows for not only large scale fabrication of various robust hydrogel microspheres with controlled size and porosity, but also the domains embedded in hydrogel network could be introduced in a modular manner. Additionally, the number of different domains and their ratio could be widely variable on demand. More importantly, the reactive groups distributed in individual domains could be used as anchor sites to further incorporate functional units in an orthogonal fashion, leading to well-defined multicompartment systems. The strategy provides a new and efficient route to construct well-defined functional multicompartment systems with great flexibility and extendibility. [ABSTRACT FROM AUTHOR]

Asymmetric Janus materials are of wide-spread interest due to their unique anisotropic and directional features. In our work, through a simple combination of nanosphere lithography at the solution interface and dopamine chemistry, a new approach for the facile synthesis of large, asymmetric, free-standing, 2D photonic Janus films with a highly tunable Janus balance and multiple functionalities is developed. Herein we rationally exploit the unique properties (reducibility, self-adhesive nature, and post-modification ability) of the polydopamine (PDA) layer and the good deformation and dissolution ability of polystyrene (PS). The precisely controllable chemical compositions on the PDA layer and the multi-variable morphologies from the PS part offer us a great chance to tune the Janus balance of the film in different dimensions. As a demonstration of the resultant Janus films for potential applications, femtoliter cup arrays are achieved after the removal of PS, which are used for confined crystallization. Good surface-enhanced Raman scattering (SERS) enhancement of the Ag-metallic Janus film is shown, which confirms this excellent platform for creating new functional materials. Our study not only bridges dopamine chemistry with 2D photonic crystals but also opens up new avenues for artificially designed Janus nanoarchitectures with multi­ple functions. [ABSTRACT FROM AUTHOR]

In this work, based on colloidal lithography, a strategy is developed to produce a new type of hybrid plasmonic–photonic system comprising a periodic array of nanoholes in a photoreconfigurable polymer layer deposited on a gold surface. By controlling the experimental conditions, the geometric parameters of the nanoholes can be easily adjusted; hence, the optical properties of the systems are widely tunable. Importantly, the shape and topology of the round nanohole arrays can be easily reconfigured with proper photoirradiation, providing a means to modulate the optical properties and produce new functionalities, as exemplified by the formation of arrays with anisotropic or gradient structural features. Moreover, rubbing dielectric spheres into the formed nanoholes can further tune the topological structures of the dielectric components in the hybrid system, leading to a dramatic modification of the spatial energy distributions and inducing the formation of uniform electromagnetic fields confined near the embedded sphere surfaces, which are more beneficial for practical applications. All the results indicate that the combined use of the unique properties of both a photoreconfigurable polymer and colloidal lithography opens a new avenue with great potential for efficient and large‐area fabrication of hybrid plasmonic–photonic systems with a high degree of optical tunability. [ABSTRACT FROM AUTHOR]

The article presents a study conducted by Wang Shiqiang and colleagues which examines the aqueous ternary system containing lithium, potassium, and sulfate ions in geochemical behavior of brine and mineral system. It mentions the methods and the result of the experiment which show that the equilibrium states can be achieved from 10-15 days of continuous stirring.