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Abstract Developing highly active materials that efficiently utilize solar spectra is crucial for photocatalysis, but still remains a challenge. Here, we report a new donor-acceptor (D-A) covalent organic framework (COF) with a wide absorption range from 200 nm to 900 nm (ultraviolet-visible-near infrared light). We find that the thiophene functional group is accurately introduced into the electron acceptor units of TpDPP-Py (TpDPP: 5,5’-(2,5-bis(2-ethylhexyl)−3,6-dioxo-2,3,5,6-tetrahydropyrrolo [3,4-c]pyrrole-1,4-diyl)bis(thiophene-2-carbaldehyde), Py: 1,3,6,8-tetrakis(4-aminophenyl)pyrene) COFs not only significantly extends its spectral absorption capacity but also endows them with two-photon and three-photon absorption effects, greatly enhancing the utilization rate of sunlight. The selective coupling of benzylamine as the target reactant is used to assess the photocatalytic activity of TpDPP-Py COFs, showing high photocatalytic conversion of 99% and selectivity of 98% in 20 min. Additionally, the TpDPP-Py COFs also exhibit the universality of photocatalytic selective coupling of other imine derivatives with ~100% conversion efficiency. Overall, this work brings a significant strategy for developing COFs with a wide absorption range to enhance photocatalytic activity.

Illicium simonsii Maxim (1888) is a medicinal species of the genus Illicium in the Illiciaceae family. It is commonly used to cure gastro-frigid vomiting, cystic hernia, gas pains in the chest, and scabies as folk medicine. To utilize its resources efficiently, the complete chloroplast genome of I. simonsii was sequenced, assembled, and annotated by using high-throughput sequencing data. The complete chloroplast genome was 143,038 bp in length, with a large single-copy region (LSC) of 101,094 bp, a short single-copy region (SSC) of 20,070 bp, and a pair of inverted repeats (IRs) of 21,874 bp. A total of 113 genes were annotated, including 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. The phylogenetic tree exhibited that I. simonsii and Illicium burmanicum form a sister group, and were nested in the monophyletic clade of the Illicium genus.

Abstract Three-dimensional (3D) printing, otherwise known as additive manufacturing in a non-technical context, is becoming increasingly popular in the field of dentistry. As an essential step in the 3D printing process, postwashing with organic solvents can damage the printed resin polymer and possibly pose a risk to human health. The development of water-washable dental resins means that water can be used as a washing agent. However, the effects of washing agents and washing times on the mechanical and biocompatibility properties of water-washable resins remain unclear. This study investigated the impact of different washing agents (water, detergent, and alcohol) and washing time points (5, 10, 20, and 30 min) on the flexural strength, Vickers hardness, surface characterization, degree of conversion, biocompatibility, and monomer elution of 3D printed samples. Using water for long-term washing better preserved the mechanical properties, caused a smooth surface, and improved the degree of conversion, with 20 min of washing with water achieving the same biological performance as organic solvents. Water is an applicable agent option for washing the 3D printing water-washable temporary crown and bridge resin in the postwashing process. This advancement facilitates the development of other water-washable intraoral resins and the optimization of clinical standard washing guidelines.

Abstract Stretchable neuromorphic optoelectronics present tantalizing opportunities for intelligent vision applications that necessitate high spatial resolution and multimodal interaction. Existing neuromorphic devices are either stretchable but not reconcilable with multifunctionality, or discrete but with low-end neurological function and limited flexibility. Herein, we propose a defect-tunable viscoelastic perovskite film that is assembled into strain-insensitive quasi-continuous microsphere morphologies for intrinsically stretchable neuromorphic vision-adaptive transistors. The resulting device achieves trichromatic photoadaptation and a rapid adaptive speed (

Abstract Challenges associated with stretchable optoelectronic devices, such as pixel size, power consumption and stability, severely brock their realization in high-resolution digital imaging. Herein, we develop a universal detachable interface technique that allows uniform, damage-free and reproducible integration of micropatterned stretchable electrodes for pixel-dense intrinsically stretchable organic transistor arrays. Benefiting from the ideal heterocontact and short channel length (2 μm) in our transistors, switching current ratio exceeding 106, device density of 41,000 transistors/cm2, operational voltage down to 5 V and excellent stability are simultaneously achieved. The resultant stretchable transistor-based image sensors exhibit ultrasensitive X-ray detection and high-resolution imaging capability. A megapixel image is demonstrated, which is unprecedented for stretchable direct-conversion X-ray detectors. These results forge a bright future for the stretchable photonic integration toward next-generation visualization equipment.

Abstract Nanoclusters with atomically precise structures and discrete energy levels are considered as nanoscale semiconductors for artificial intelligence. However, nanocluster electronic engineering and optoelectronic behavior have remained obscure and unexplored. Hence, we create nanocluster photoreceptors inspired by mantis shrimp visual systems to satisfy the needs of compact but multi-task vision hardware and explore the photo-induced electronic transport. Wafer-scale arrayed photoreceptors are constructed by a nanocluster-conjugated molecule heterostructure. Nanoclusters perform as an in-sensor charge reservoir to tune the conductance levels of artificial photoreceptors by a light valve mechanism. A ligand-assisted charge transfer process takes place at nanocluster interface and it features an integration of spectral-dependent visual adaptation and circular polarization recognition. This approach is further employed for developing concisely structured, multi-task, and compact artificial visual systems and provides valuable guidelines for nanocluster neuromorphic devices.

Abstract Metal-nitrogen-carbon catalysts with hierarchically dispersed porosity are deemed as efficient geometry for oxygen reduction reaction (ORR). However, catalytic performance determined by individual and interacting sites originating from structural heterogeneity is particularly elusive and yet remains to be understood. Here, an efficient hierarchically porous Fe single atom catalyst (Fe SAs-HP) is prepared with Fe atoms densely resided at micropores and mesopores. Fe SAs-HP exhibits robust ORR performance with half-wave potential of 0.94 V and turnover frequency of 5.99 e−1s−1site−1 at 0.80 V. Theoretical simulations unravel a structural heterogeneity induced optimization, where mesoporous Fe-N4 acts as real active centers as a result of long-range electron regulation by adjacent microporous sites, facilitating O2 activation and desorption of key intermediate *OH. Multilevel operando characterization results identify active Fe sites undergo a dynamic evolution from basic Fe-N4 to active Fe-N3 under working conditions. Our findings reveal the structural origin of enhanced intrinsic activity for hierarchically porous Fe-N4 sites.

Control of the interfacial microstructures and mechanical properties of aluminum/steel joints after welding is crucial to prolonging the service lives of such structures. In this study, the influence of post-welding heat treatment (PWHT) on aluminum/steel laser-arc weld-brazing joints was investigated, with particular focus on the evolution mechanisms of the interfacial microstructures and regulation of the mechanical properties. Transmission electron microscopy (TEM) and electron backscatter diffraction (EBSD) results confirmed the presence of the monoclinic Fe4Al13 and hexagonal Al8Fe2Si phases at the aluminum/steel interface. Upon increasing the heat-treatment temperature, micro-characteristics of the intermetallic compound (IMC) passed through three different stages (weak elemental diffusion–reaction–drastic change) depending on the temperature employed; these stages differed from the PWHT phenomenon observed for the aluminum/steel solid-state welded joints. EBSD analyses revealed decreases in the grain size and textural strength of the IMC layer following PWHT at 180 °C/1 h, while the Fe4Al13 phase gradually transformed into Al8Fe2Si phase during PWHT at 520 °C/1 h, ultimately leading to an increase in the grain size and a higher textural strength. Additionally, PWHT effectively eliminated the residual tensile stress in aluminum/steel joints and improved the softening of the heat-affected zone (HAZ). Upon PWHT at 180 °C/1 h, the synergistic effects of the elimination of residual stress, an enhanced softening in the HAZ, and changes in the IMC layer, led to improved joint properties. Furthermore, the maximum tensile strengths of the joints with and without reinforcement increased to 221.9 MPa (from 209.8 MPa) and 165.3 MPa (from 148.1 MPa), respectively.

AbstractZiziphus mairei Dode 1908 (Rhamnaceae) is a rare and endangered perennial plant in Yunnan, China. In this study, we sequenced, assembled, and annotated the complete chloroplast genome of Z. mairei. The complete chloroplast genome was a closed circular molecule of 161,546 bp with a typical tetrad structure, containing a large single-copy (LSC) region of 89,252 bp, a small single-copy (SSC) region of 19,364 bp, and a pair of inverted repeat (IR) regions of 26,465 bp. A total of 128 genes have been annotated, including 83 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The GC content is 36.7%. Phylogenetic analysis revealed that Z. mairei is closely related to Z. hajarensis, Z. jujuba, and Z. jujuba var. spinosa. Our results provide useful genetic resources for further studies on the conservation and evolution of Z. mairei.

This study investigated the influence of Cd (25 µM) on Zn accumulation in a hyperaccumulating (HE) and a non-hyperaccumulating (NHE) ecotype of Sedum alfredii Hance at short-term supply of replete (Zn5, 5 µM) and excess (Zn400, 400 µM) Zn. Cd inhibited Zn accumulation in both ecotypes, especially under Zn400, in organs with active metal sequestration, i.e. roots of NHE and shoots of HE. Direct biochemical Cd/Zn competition at the metal-protein interaction and changes in transporter gene expression contributed to the observed accumulation patterns in the roots. Specifically, in HE, Cd stimulated SaZIP4 and SaPCR2 under Zn5, but downregulated SaIRT1 and SaZIP4 under Zn400. However, Cd downregulated related transporter genes, except for SaNRAMP1, in NHE, irrespective of Zn. Cadmium stimulated casparian strip (CSs) development in NHE, as part of the defense response, while it had a subtle effect on the (CS) in HE. Moreover, Cd delayed the initiation of the suberin lamellae (SL) in HE, but stimulated SL deposition in NHE under both Zn5 or Zn400. Changes in suberization were mainly ascribed to suberin-biosynthesis-related genes and hormonal signaling. Altogether, Cd regulated Zn accumulation mainly via symplasmic and transmembrane transport in HE, while Cd inhibited both symplasmic and apoplasmic Zn transport in NHE.

Public use and sharing of vector data while preserving its confidentiality is a critical challenge in geographic information security. Geometric accuracy reduction processing is commonly employed to process high-precision vector data containing a large amount of sensitive information into publicly available lower-precision data, which can balance the confidentiality and publicity of vector data. However, current research struggles to satisfy the security, controllability, and availability of processed data simultaneously. To address this issue, we propose a novel ellipsoid spatial mapping-based method for reducing the geometric accuracy of vector data. This method involves designing a model that utilizes Earth ellipsoid and spatial mapping techniques to safeguard vector data with irreversible offsets. We also develop offset variation functions for the x- and y-directions based on the model and predefined parameters, ensuring the availability and controllability of the processed data. Experimental results indicate that our method satisfies controllable accuracy reduction requirements, preserves the significant majority of shape and topology of the original data, and provides faster processing speeds compared to other methods. Our method ensures that processed data complies with confidentiality regulations, promoting the broader application of vector data.

Abstract Intrinsically stretchable semiconducting polymers are promising candidates for developing wearable electronics, but remain underdeveloped because the correlation between the microstructural evolution during stretching and the resultant charge transport is not clearly understood. In this study, we clarify the impact of molecular orientation on the dynamic performance of stretched semiconducting polymers, controlling molecular orientations via solvent-dependent spin-coating. We found that strain-enhanced electrical performance is feasible by quelling disorders within the face-on-packed aggregates. Strain facilitates 3D ordering in face-on-packed films, but increase the π-π orientation disorders and lamellar dislocation in the edge-on analogue, which contribute inversely to the charge transport. Consequently, the face-on samples maintain strain-resistant energetic disorder and a 1.5× increase in on-current, achieving a 10-times-higher retention than the edge-on analogue upon 100% strain. Furthermore, we developed a reliable way for measuring the photoelectrical stretchability of semiconducting polymer. This study contributes to developing high-performance stretchable semiconducting polymers.

Abstract A series of new π‐conjugated macrocycles (AzoM‐n‐E, n = 1–3) incorporating azobenzene units have been synthesized by a facile strategy in one‐pot reaction. The resultant azobenzene‐embedded macrocycles feature intrinsic photoresponsive behaviors and intriguing supramolecular assembling properties. The smallest macrocycle AzoM‐1‐E with a rigid planar conjugated backbone structure is used to prepare the single crystal transistors, showing reversible optical tunability. The moderate size macrocycle AzoM‐2‐E assembles into a dimer in the form of interpenetration through π‐π stacking between azobenzene units. The largest macrocycle AzoM‐3‐E with enhanced flexibility can adaptively assemble with various types of electron‐deficient guests accompanied by distortion of azobenzene. Typically, AzoM‐3‐E assembles with the planar F4‐TCNQ to form a tetragonal geometry by C‐F···π and π‐π interactions, while the assembly with ellipsoidal C70 via π‐π interactions induces AzoM‐3‐E to form a boat‐shaped geometry. This work will shed new light on the development of functional conjugated macrocycles in organic electronics.

Abstract Polymer nanowire (NW) organic field-effect transistors (OFETs) integrated on highly aligned large-area flexible substrates are candidate structures for the development of high-performance flexible electronics. This work presents a universal technique, coaxial focused electrohydrodynamic jet (CFEJ) printing technology, to fabricate highly aligned 90-nm-diameter polymer arrays. This method allows for the preparation of uniformly shaped and precisely positioned nanowires directly on flexible substrates without transfer, thus ensuring their electrical properties. Using indacenodithiophene-co-benzothiadiazole (IDT-BT) and poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8-BT) as example materials, 5 cm2 arrays were prepared with only minute size variations, which is extremely difficult to do using previously reported methods. According to 2D-GIXRD analysis, the molecules inside the nanowires mainly adopted face-on π-stacking crystallite arrangements. This is quite different from the mixed arrangement of thin films. Nanowire-based OFETs exhibited a high average hole mobility of 1.1 cm2 V−1 s−1 and good device uniformity, indicating the applicability of CFEJ printing as a potential batch manufacturing and integration process for high-performance, scalable polymer nanowire-based OFET circuits. This technique can be used to fabricate various polymer arrays, enabling the use of organic polymer semiconductors in large-area, high-performance electronic devices and providing a new path for the fabrication of flexible displays and wearable electronics in the future.

Primula vialii Delavay ex Franch. (1905) is an alpine species with an ornamental value. In this study, we sequenced, assembled, and annotated the chloroplast genome of P. vialii. The results showed that it was a double-stranded, closed circular DNA with 154,897 bp in length, comprising a small single-copy (SSC) region of 17,766 bp, a large single-copy (LSC) region of 85,379 bp and a pair of inverted repeat (IR) regions of 25,876 bp. A total of 113 unique genes were annotated, including 79 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. The phylogenetic analysis revealed that P. vialii is closely related to Primula flaccida. The cp genomic data will be useful for systematics and evolutionary studies of Primula.

Laser–MIG hybrid welding–brazing was used to weld 304 stainless steel and 6061-T6 aluminum alloy with a thickness of 2 mm. The microstructure, morphology, chemical composition and corrosion behavior of the samples after high-temperature oxidation were investigated. The results reveal that the 304/6061 dissimilar joint had a thicker intermetallic compound layer (7–8 μm) during high-temperature oxidation (HTO) treatment than the sample without HTO treatment (2–3 μm). The oxide film thickness of the 6061 side of the weld joint treated by HTO (2401 nm) increased compared to the samples (181.1 nm) without HTO treatment. Unlike other metals treated by high-temperature oxidation, the high-temperature treatment process in this paper can reduce the corrosion resistance of the base metal and dissimilar joints, and the sequence of the corrosion current density was weld (HTO) >weld>6061 (HTO) >6061>304 (HTO) >304.

Cardiac ventricular arrhythmia triggered by acute myocardial infarction (AMI) is a major cause of sudden cardiac death. We have reported previously that an increased serum level of circular RNA CDR1as is a potential biomarker of AMI. However, the possible role of CDR1as in post-infarct arrhythmia remains unclear. This study in MI mice investigated the effects and underlying mechanism of CDR1as in ventricular arrhythmias associated with MI. We showed that knockdown of CDR1as abbreviated the duration of the abnormally prolonged QRS complex and QTc intervals and decreased susceptibility to ventricular arrhythmias. Optical mapping demonstrated knockdown of CDR1as also reduced post-infarct arrhythmia by increasing the conduction velocity and decreasing dispersion of repolarization. Mechanistically, CDR1as led to the depletion of NAD+ and caused mitochondrial dysfunction by directly targeting the NAMPT protein and repressing its expression. Moreover, CDR1as aggravated dysregulation of the NaV1.5 and Kir6.2 channels in cardiomyocytes, a change which was alleviated by the replenishment of NAD+. These findings suggest that anti-CDR1as is a potential therapeutic approach for ischemic arrhythmias.

We design and simulate a new type of hollow-core antiresonant fiber with the polygon jacketing layer. Through numerical calculations, the confinement loss is approximately 0.003 dB/km at 1.45 μm and the bandwidth is ∼ 410 nm @ CL < 0.1 dB/km. We found that more nested tubes can be connected to the jacketing layer to avoid the generation of more cladding nodes. The nested tube cladding with the small size of air holes can effectively suppress the coupling between the fiber cladding and core modes even at extreme bending conditions. Ultra-low bending loss is achieved, and the bending loss is lower than ∼ 0.05 dB/km @ bend radius Rb = 3 cm at 1.50 μm.

Secure retrieval of remote sensing images in an outsourced cloud environment garners considerable attention. Since the cloud service provider (CSP) is considered as a semitrusted third party that may return incorrect retrieval results to save computational resources or defraud retrieval fees for profit, it becomes a critical challenge to achieve secure and verifiable remote sensing image retrieval. This article presents a secure retrieval and blockchain-assisted verifiable scheme for encrypted remote sensing images in the cloud environment. In response to the characteristic that geographical objects in remote sensing images with clear category attributes, we design a remote sensing image retrieval method to facilitate secure and efficient retrieval. In addition, we propose a verifiable method combined with blockchain and Merkle trees for checking the integrity and correctness of the storage and retrieval services provided by CSP, which can replace the traditional third-party auditor. The security analysis and experimental evaluation demonstrate the security, verifiability, and feasibility of the proposed scheme, achieving secure remote sensing image retrieval while preventing malicious behavior of CSP.

Abstract We study dynamic processes through which the scalar hair of black holes is generated or detached in a theory with a scalar field non-minimally coupled to Gauss-Bonnet and Ricci scalar invariants. We concentrate on the nonlinear temporal evolution of a far-from-equilibrium gravitational system. In our simulations, we choose the initial spacetime to be either a bald Schwarzschild or a scalarized spherically symmetric black hole. Succeeding continuous accretion of the scalar field onto the original black hole, the final fate of the system displays intriguing features, which depend on the initial configurations, strengths of the perturbation, and specific metric parameters. In addition to the scalarization process through which the bald black hole addresses scalar hair, we observe the dynamical descalarization, which removes scalar hair from an original hairy hole after continuous scalar field accretion. We examine the temporal evolution of the scalar field, the metrics, and the Misner-Sharp mass of the spacetime and exhibit rich phase structures through nonlinear dynamical processes.

2D and 3D conductive MOFs have performed well in the fields of energy and catalysis. Here, authors synthesise a 1D conductive MOF in which DDA ligands are connected by double Cu ions, forming nanoribbon layers with π-d conjugated nanoribbon planes and out-of-plane π-π stacking, which facilitates charge transport along two dimensions.

Primula odontocalyx (Franch.) Pax (1905) is a perennial herb of the genus Primula in Primulaceae with heterostyly and ornamental value. Here, the chloroplast genome of P. odontocalyx was sequenced, assembled, and annotated. The complete chloroplast genome was a closed-circular molecule of 151,738 bp in length, containing a large single-copy region (LSC) of 83,817 bp, a small single-copy region (SSC) of 17,529 bp, and two inverted repeat (IR) regions of 25,196 bp. A total of 115 unique genes were annotated in the whole cp genome, including 81 protein-coding genes, 4 rRNA genes, and 30 tRNA genes. Phylogenetic analysis confirmed the close relationship between P. odontocalyx and Primula moupinensis, and both species belong to Sect. Petiolares Pax.

Wearable and skin-like X-ray detectors need intrinsic flexibility and high sensitivity. Here Guo et al. develop a stretchable n-type polymer semiconductor with aligned nanofiber networks which achieve photosensitivity of 1.52×10^4 μC Gyair^-1 cm^−2 and low detection limit of 37.7 nGyair s^-1.

Abstract Although the effects of electron‐deficient group substitution on isoindigo on the corresponding conjugated polymers are extensively studied, the modification of isoindigo core with electron‐rich groups has not been investigated. It is envisioned that the introduction of the methoxy group on isoindigo will not only tune the highest occupied molecular orbital (HOMO) energy level of the corresponding polymers but also introduce O···S “conformation lock” to increase the coplanarity of the polymers, which should facilitate hole transport. Herein, the syntheses of two methoxylated isoindigos and the investigations on the charge transport behaviors of their copolymers with bisthiophene (2T) and bisthiazole (2Tz) are reported. It is found that the substitution positions have a drastic influence on the UV–vis absorption and electrochemical properties for both monomers and polymers. Theoretical calculations and single crystal structure analysis confirm the existence of O···S “conformation lock”, however, both methoxy substitutions also change the aggregation behaviors of the corresponding polymers to a mixed face‐on/edge‐on orientation which has an adverse effect for charge transport. Among the four polymers, the polymer of 5,5'‐methoxylated isoindigo and 2T exhibit the best hole mobility of 1.9 × 10−1 cm2 V−1 s−1.

Abstract Highly aligned aggregation state structures have great significance for effective charge‐carrier transport in organic semiconductors. Several methods have been developed to provide organic semiconducting molecules with highly oriented aggregation state structure; among these, using a water surface to form organic semiconductor films is a widely implemented strategy, wherein solutions are spread on the surface of water. However, common techniques of film formation on water surfaces generally result in a nonuniform orientation of the film owing to the isotropic spread process of droplets on the water surface. In this study, a spatially confined air/water interfacial assembly method is proposed to obtain uniformly aligned monolayer and multilayer poly(diketopyrrolopyrrole‐thieno[3,2‐b]thiophene) thin films with controlled thickness. The structural and morphological characterizations obtained using atomic force microscopy, high‐resolution transmission electron microscopy, and grazing incidence wide‐angle X‐ray scattering indicates the crystalline structure of the thin films and high alignment of the molecular chains. The maximum mobility of the thin films reaches up to 2.06 and 0.5 cm2 V−1 s−1 in the parallel and perpendicular direction, respectively, indicating apparent anisotropic electrical properties. Furthermore, an inverter based on these thin films exhibits a voltage gain of up to 70, demonstrating the potential of applying the proposed technique to logic circuits.

Here, the authors fabricate large area and highly aligned polymer semiconductor sub-microwires arrays via coaxial focused electrohydrodynamic jet printing technology, achieving high on/off ratio and average mobility that is 5x higher than that of thin film based organic field effect transistors.

Understanding the slow kinetics of hydrogen evolution reaction in neutral media is of fundamental importance for the rational design of high-performance electrocatalysts for hydrogen energy. Here, by studying Ru single atom and RuSe x cluster, the authors report how the rate of hydrogen evolution reaction activity in neutral media is governed by interfacial water.

Primula calliantha subsp. bryophila (Balf. f. et Farrer) W.W. Smith and Forrest (1928) is a perennial alpine species with ornamental value. It is distributed in northwestern Yunnan and adjacent eastern Tibet of China, and northern Myanmar. Here, we sequenced and assembled complete plastid genome of P. calliantha subsp. bryophila, which is a circular molecule of 152,045 bp in length, including a large single-copy region (83,966 bp), a small single-copy region (17,663 bp), and a pair of inverted repeats (25,208 bp). The chloroplast genome contained 113 genes, including 79 protein-coding genes, four rRNA genes, and 30 tRNA genes. The phylogenetic tree based on chloroplast genomes showed the relative relationship of P. calliantha subsp. bryophila and P. calliantha, which further supports P. calliantha subsp. bryophila as a subspecies of P. calliantha in taxonomy. The complete chloroplast (cp) genome of P. calliantha subsp. bryophila provides valuable data for further phylogenetic studies of Primulaceae.

Abstract In the epitaxial growth of two-dimensional (2D) materials on substrates, 2D polycrystals with various shapes have been broadly observed, but their formation mechanisms are still highly elusive. Here we present a complete study on the formation mechanisms of various 2D polycrystals. The structures of the 2D polycrystals are dependent on the symmetries of both the 2D material and the substrate. We build four complete libraries of 2D polycrystals for (i) threefold symmetric 2D materials on two- or six-fold symmetric substrates (i.e., family-III/II or -III/VI), (ii) threefold symmetric 2D materials on fourfold symmetric substrates (i.e. family-III/IV), (iii) fourfold symmetric 2D materials on three- or six-fold symmetric substrates (i.e., family-IV/III or -IV/VI), and (iv) sixfold symmetric 2D materials on fourfold symmetric substrates (i.e., family-VI/IV), respectively. The four libraries of 2D polycrystals are consistent with many existing experimental observations and can be used to guide the experimental synthesis of various 2D polycrystals.

The influences on the tuning range of a wavelength-tunable L-band mode-locked fiber lasers incorporating a long-period fiber grating (LPFG) are investigated. Through controlling both resonance wavelength and bandwidth of the LPFG, the net gain of the laser can be designed appropriately, hence leading to an optimized tuning range of the L-band mode-locked lasers. A wide spectral tuning range of 23.98 nm is obtained when using the LPFG with 21.60 nm bandwidth. Benefiting from the narrow band optical attenuation characteristic of LPFG, the lowest power variation of the laser is merely 4.15 µW/nm. Moreover, theoretical gain analysis corresponds to the experimental observation well.

Solution-based synthesis of covalent organic frameworks (COFs) often leads to insoluble powders or fragile films on solution surfaces. Here, the authors report large-area two-dimensional (2D) COF films with controllable thicknesses via vapour induced conversion.

Abstract Flexible electronics have suggested tremendous potential to shape human lives for more convenience and pleasure. Strenuous efforts have been devoted to developing flexible organic field-effect transistor (FOFET) technologies for rollable displays, bendable smart cards, flexible sensors and artificial skins. However, these applications are still in a nascent stage for lack of standard high-performance material stacks as well as mature manufacturing technologies. In this review, the material choice and device design for FOFET devices and circuits, as well as the demonstrated applications are summarized in detail. Moreover, the technical challenges and potential applications of FOFETs in the future are discussed.

As a crucial component of nonlinear polarization rotation (NPR) mode locking, optical fiber gratings offer advantages such as polarization modulation capability, stability, fiber compatibility, and preparation maturity, making them a vital technological foundation for achieving NPR mode locking. Here, a polarization-maintaining fiber helical long-period grating (PMF-HLPG) was designed and fabricated as a polarizer using the CO2-laser direct-write technique to realize the NPR effect. A homemade fiber Bragg grating (FBG) was also introduced into the laser system to enable a narrow-bandwidth lasing output and wavelength tunability. Based on the PMF-HLPG and FBG mentioned above, an all-fiber mode-locked laser with a spectra bandwidth of 0.15 nm was constructed to generate stable short pulses with a fundamental repetition rate of 12.7122 MHz and a pulse duration of 30.08 ps. In particular, its signal-to-noise ratio is up to 84.5 dB, showing the high stability of the laser. Further, the operating wavelength of the laser can be tuned from 1559.65 nm to 1560.29 nm via heating the FBG while maintaining its mode-locked state with stability. The results indicate that the PMF-HLPG could be used as a polarizer to meet the NPR mechanism for ultrashort pulse laser applications in optical communication, optical sensing, and biomedical imaging.

Abstract Background To provide multivariable prognostic models for severe complications prediction after heart valve surgery, including low cardiac output syndrome (LCOS), acute kidney injury requiring hemodialysis (AKI-rH) and multiple organ dysfunction syndrome (MODS). Methods We developed multivariate logistic regression models to predict severe complications after heart valve surgery using 930 patients collected retrospectively from the first affiliated hospital of Sun Yat-Sen University from January 2014 to December 2015. The validation was conducted using a retrospective dataset of 713 patients from the same hospital from January 2016 to March 2017. We considered two kinds of prognostic models: the PRF models which were built by using the preoperative risk factors only, and the PIRF models which were built by using both of the preoperative and intraoperative risk factors. The least absolute shrinkage selector operator was used for developing the models. We assessed and compared the discriminative abilities for both of the PRF and PIRF models via the receiver operating characteristic (ROC) curve. Results Compared with the PRF models, the PIRF modes selected additional intraoperative factors, such as auxiliary cardiopulmonary bypass time and combined tricuspid valve replacement. Area under the ROC curves (AUCs) of PRF models for predicting LCOS, AKI-rH and MODS are 0.565 (0.466, 0.664), 0.688 (0.62, 0.757) and 0.657 (0.563, 0.751), respectively. As a comparison, the AUCs of the PIRF models for predicting LOCS, AKI-rH and MODS are 0.821 (0.747, 0.896), 0.78 (0.717, 0.843) and 0.774 (0.7, 0.847), respectively. Conclusions Adding the intraoperative factors can increase the predictive power of the prognostic models for severe complications prediction after heart valve surgery.

Abstract In principle, polymerization tends to produce amorphous or poorly crystalline materials. Efficiently producing high-quality single crystals by polymerization in solvent remains as an unsolved issue in chemistry, especially for covalent organic frameworks (COFs) with highly complex structures. To produce μm-sized single crystals, the growth time is prolonged to >15 days, far away from the requirements in practical applications. Here, we find supercritical CO2 (sc-CO2) accelerates single-crystal polymerization by 10,000,000 folds, and produces two-dimensional (2D) COF single crystals with size up to 0.2 mm within 2~5 min. Although it is the fastest single-crystal polymerization, the growth in sc-CO2 leads to not only the largest crystal size of 2D COFs, but also higher quality with improved photoconductivity performance. This work overcomes traditional concept on low efficiency of single-crystal polymerization, and holds great promise for future applications owing to its efficiency, industrial compatibility, environmental friendliness and universality for different crystalline structures and linkage bonds.

Summary: Syntheses using classic coupling reactions can be tedious, leading to a dearth of ambipolar semiconducting polymers. Here, we detail the rapid synthesis of balanced ambipolar polymers by using a carbon-hydrogen (C–H) activation strategy. Using this protocol, two C–H reactive hydrogenated monomers and six ambipolar polymers can be rapidly synthesized within 2 h via C–H activation and the optoelectronic properties of the resultant polymers can be characterized. We also describe the fabrication process and performance evaluation of the ambipolar polymers-based organic transistors.For complete details on the use and execution of this protocol, please refer to Shen et al. (2022). : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Realizing organic p–n junctions based on ordered crystalline materials with dimensions comparable to the exciton diffusion length of most organic semiconductors remains a challenge. Here, the authors report a strategy to form molecular monolayer crystal-based p–n junctions with thickness below 5 nm.

Summary: Background: In the current practice, graft ischaemia and reperfusion injury (IRI) is considered an inevitable component in organ transplantation, contributes to compromised organ quality, inferior graft survival and limitations in organ availability. Among all the donor organs, the heart is most vulnerable to IRI and the tolerated ischaemic time is the shortest. Methods: By combining adapted surgical techniques and normothermic machine perfusion (NMP), we performed the first case of ischaemia-free beating heart transplantation (IFBHT) in man. The donor heart was procured after an in situ NMP circuit was established, then underwent ex situ NMP and implanted under NMP support. The post-transplant graft function was monitored. Findings: The donor heart was procured, preserved, and implanted under a continuously perfused, normothermic, oxygenated, beating state. During ex situ NMP, the donor heart beat with sinus rhythm and adequate ventricular contraction, consumed oxygen and lactate, suggesting a good cardiac function. The dynamic electrocardiogram demonstrated an absence of ischaemic injury of the donor heart during the entire procedure. The echocardiogram showed an immediate graft function with a left ventricle ejection fraction (LVEF) of 70%. The patient was discharged on post-transplantation day 20 and was followed up for 8 months with normal cardiac function and life. Interpretation: This study shows the feasibility of IFBHT procedure, which might be able to completely avoid graft IRI, has thus the potential to improve transplant outcome while increasing organ utilization. Funding: This study was funded by National Natural Science Foundation of China, Guangdong Provincial Key Laboratory Construction Projection on Organ Donation and Transplant Immunology, and Guangdong Provincial International Cooperation Base of Science and Technology.

Abstract Aims Previous reports indicated that the Slit2–Robo signalling pathway is involved in embryonic heart development and fibrosis in other solid organs, but its function in adult cardiac fibrosis has not been investigated. Here, we investigate the role of the Slit2–Robo1 signalling pathway in cardiac fibrosis. Methods and results The right atrial tissue samples were obtained from patients with valvular heart disease complicated by atrial fibrillation during heart valve surgery and from healthy heart donors. The fibrotic animal model is created by performing transverse aortic constriction (TAC) surgery. The Robo1, Slit2, TGF‐β1, and collagen I expression levels in human and animal samples were evaluated by immunohistochemistry and western blot analysis. Echocardiography measured the changes in heart size and cardiac functions of animals. Angiotensin II (Ang II), Slit2‐siRNA, TGF‐β1‐siRNA, recombinant Slit2, and recombinant TGF‐β1 were transfected to cardiac fibroblasts (CFs) respectively to observe their effects on collagen I expression level. The right atrial appendage of patients with valvular heart disease complicated by atrial fibrillation found significantly up‐regulated Slit2, Robo1, TGF‐β1, and collagen I expression levels. TAC surgery leads to heart enlargement, cardiac fibrosis, and up‐regulation of Slit2, Robo1, TGF‐β1, and collagen I expression levels in animal model. Robo1 antagonist R5 and TGF‐β1 antagonist SB431542 suppressed cardiac fibrosis in TAC mice. Treatment with 100 nM Ang II in CFs caused significantly increased Slit2, Robo1, Smad2/3, TGF‐β1, collagen I, PI3K, and Akt expression levels. Transfecting Slit2‐siRNA and TGF‐β1‐siRNA, respectively, into rat CFs significantly down‐regulated Smad2/3 and collagen I expression, inhibiting the effects of Ang II. Recombinant Slit2 activated the TGF‐β1/Smad signalling pathway in CFs and up‐regulated Periostin, Robo1, and collagen I expression. Conclusions The Slit2–Robo1 signalling pathway interfered with the TGF‐β1/Smad pathway and promoted cardiac fibrosis. Blockade of Slit2–Robo1 might be a new treatment for cardiac fibrosis.

Aiming at the technical difficulty of poor teeth accuracy of the extruded sun gears, an innovative precision finishing approach was developed as the subsequent process of producing high-quality sun gears, and three finishing tools were designed, namely mandrel with gap, mandrel without gap and interference mandrel. A finite element prediction method was proposed by using the post-processing toolbox of DEFORM software to study the distribution laws of outer and inner teeth deviations of the reshaped sun gear. Moreover, the effects of various precision finishing tools on the formability of sun gear (such as tooth deformation, tool stress and tooth accuracy) were investigated. The results show that the tooth accuracy class of the reshaped outer teeth in profile and helix were seventh and eighth, respectively, and the total M-value error of the inner teeth was decreased to 72.3 μm and the reduction ratio was 73.8% by adopting the interference mandrel, which indicates that the finishing effect of the interference mandrel was better than that of mandrels for both with gap and without gap, and the forming accuracy of the finished teeth could be considerably improved. Therefore, the interference mandrel can be recommended as the optimum finishing tool in the manufacture of precision sun gears. The simulated results were in good agreement with experimental ones within a maximum error of 14.4%, which proves the practicability of the sizing approach and the dependability of the finite element prediction method.

Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) are involved in the mechanism underlying cerebral dysfunction after deep hypothermic circulatory arrest (DHCA), although the exact details have not been elucidated. To explore the expression profiles of lncRNAs and miRNAs in DHCA cerebral injury, we determined the lncRNA, miRNA and mRNA expression profiles in the cerebral cortex of DHCA and sham rats. First, a rat model of DHCA was established, and high-throughput sequencing was performed to analyze the differentially expressed RNAs (DERNAs). Then, the principal functions of the significantly deregulated genes were identified using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Expression networks (lncRNAs-miRNAs-mRNAs and transcription factors (TFs)-miRNAs-mRNAs) were also established. Finally, the expression of DERNAs was confirmed by quantitative real-time PCR (RT-qPCR). We identified 89 lncRNAs, 45 miRNAs and 59 mRNAs between the DHCA and sham groups and constructed a comprehensive competitive endogenous RNAs (ceRNAs) network. A TF-miRNA-mRNA regulatory network was also established. Finally, we predicted that Lcorl-miR-200a-3p-Ttr, BRD4-Ccl2 and Ep300-miR-200b-3p-Tmem72 may participate in the pathogenesis of DHCA cerebral injury.

Abstract Objective: To evaluate the mid-term survival rate after tricuspid valve replacement (TVR). Methods: We retrospectively studied 110 consecutive patients who underwent TVR from January 2007 to November 2017. A survival analysis was performed with the Kaplan-Meier method and the log-rank test. Results: The median survival was 65.81 months. Mean age was 50 (range 39 to 59) years. Forty-eight patients (43.6%) were male, and 62 patients (56.4%) were female. Most of the patients (78.5%) were categorized into the New York Heart Association (NYHA) functional classes III/IV. Seventy-two patients (65.5%) had isolated TVR. Six-three patients (57.3%) had previously undergone heart surgery. The Kaplan-Meier survival rates at one year, three years, and five years were 59.0%±5%, 52.0%±6%, and 48.0%±6%, respectively. A Cox regression analysis demonstrated that the risk factors for mid-term mortality were advanced NYHA class (hazard ratio [HR] 2.430, 95% confidence interval [CI] 1.099-5.375, P=0.028), need for continuous renal replacement therapy (CRRT) treatment (HR 3.121, 95% CI 1.610-6.050, P=0.001), and need for intra-aortic balloon pump (IABP) treatment (HR 3.356, 95% CI 1.072-10.504, P=0.038). Conclusion: In TVR, impaired cardiac function before the operation and a need for CRRT or IABP treatment after the operation is independently associated with increased mid-term mortality.

The Bacillus haemolytic enterotoxin haemolysin BL has been shown to activate the NLRP3 inflammasome. Here the authors show that a non-haemolytic enterotoxin (NHE) from B. cereus can also activate the NLRP3 inflammasome with a similar mechanism of lytic pore formation.

Intrinsically stretchable organic field-effect transistors (STOFETs) that behave much like skin, have garnered widespread attention and demonstrated potential to more comfortable wearing electronics. Despite considerable efforts being exerted in stretchable hybrid polymeric semiconductors to achieve high-mobility and high-stretchability STOFETs, carbon nanotubes (CNTs) as ideal electrode materials, its interfacial quality seldom attracts research interests. Herein, we demonstrate a novel and general strategy on flexible CNT-based heterojunction electrodes by pentacene modification layer to enable high-performance and functional STOFETs. Pentacene transition layer can reduce the surface roughness and tune the heterogeneity of functional groups on the CNT thin film, as well as enhance the compatibility and van der Waals contact between CNT electrodes and organic semiconductors. The experimental results reveal that the carrier mobility of the resulting STOFETs increases by 2-3 times and the subthreshold slope decreases by 5 times compared with unmodified devices. The on-current/off-current ratio reaches nearly 107, which is approximately 1000 times as high as unmodified devices, and the highest value for stretchable organic transistors reported so far. Furthermore, STOFETs with heterojunction electrodes demonstrate better performance homogeneity and higher strain-independent capability. Noteworthy, these are the first intrinsically stretchable organic phototransistors (STOPTs) with superior photoswitching performances and high strain tolerance developed.

A miniaturized 150 kV DC photocathode gun is developed at Peking University to generate electron beam which can be manipulated in temporal and spatial distribution as requirements freely. To measure the bunch length which is an important temporal parameter of the low energy electron beam from the DC photocathode gun, a 1.3 GHz medium-β disk-loaded deflecting cavity is adopted. In this paper we present the design of the deflecting cavity which involves the microwave design including the geometry optimization and the separation of the orthogonal dipole modes as well as the power coupling, the mechanical design including the determination of the cavity wall thickness and the tuning as well as brazing structure, and the thermodynamic analysis. Particle tracking simulation shows that the best resolution of 190 fs can be achieved for the 150 keV electron beam by using the deflecting cavity. Its fabrication is completed and the RF measurements are carried out with a vector network analyzer. It is shown the measured values of the RF physical parameters are in good agreement with the simulation design ones.

Background: RBMS3 (RNA-binding motif, single-stranded-intervacting protein 3) acts as a tumor-suppressive gene in a number of human cancers, however, its role in breast cancer is not fully understood. This study aimed to investigate the expression and clinicopathological significance of RBMS3 in breast cancer. Methods: A total of 998 breast cancer tissue samples in The Cancer Genome Atlas (TCGA) database with survival outcomes were divided into high RBMS3 expression and low expression groups using the median as the cutoff. Clinicopathological characteristics and prognosis were compared between the 2 groups. Results: TCGA showed that RBMS3 mRNA was downregulated in breast cancer tissues, and RBMS3 downregulation was correlated with poor prognosis. Immunohistochemistry staining of 127 paraffin-embedded breast cancer tissues showed that RBMS3 protein was localized in the cytoplasm and nucleus; however, nuclear staining was present in 90.0% of normal breast tissues but only 28.3% of breast cancer tissues. Decreased RBMS3 protein expression was significantly correlated with estrogen receptor (ER)-negative status and death at final follow-up. Patients with lower RBMS3 protein expression had substantially shorter survival than those with higher RBMS3 expression. Univariate and multivariate analysis indicated that the combination of RBMS3 expression and ER status (a variable designated as “cofactor”) was an independent prognostic factor in patients with breast cancer (hazard ratio [HR] = 0.420, 95% confidence interval [CI]: 0.223-0.791, P = 0.007). Conclusion: RBMS3 downregulation was correlated with poor prognosis in breast cancer patients, and the combination of RBMS3 expression and ER status was an independent prognostic factor.

Field effect transistors based on graphene hold promise for future sensing applications. Here, the authors report a free radical sensor in which the •OH radical cuts cysteamine to release Cd2 + from the electrolyte/graphene interface and selectively detects •OH with a concentration down to 10−9 M.