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Beryllium-doped boron clusters display essential similarities to borophene (boron sheet) with a molecular structure characterized by remarkable properties, such as anisotropy, metallicity and high conductivity. Here we have determined low-energy structures of BeBn0/− (n = 10–20) clusters by utilizing CALYPSO searching program and DFT optimization. The results indicated that most ground states of clusters prefer plane or quasi-plane structures by doped Be atom. A novel unexpected fascinating planar BeB16− cluster with C2v symmetry is uncovered which possesses robust relative stability. Furthermore, planar BeB16− offers a possibility to construct metallo-borophene nano-materials. Molecular orbital and chemical bonding analysis reveal the peculiarities of BeB16− cluster brings forth the aromaticity and the strong interaction of B-B σ-bonds in boron network. [ABSTRACT FROM AUTHOR]

Achieving a more balanced charge transport by morphological control is crucial in reducing bimolecular and trap‐assisted recombination and enhancing the critical parameters for efficient organic solar cells (OSCs). Hence, a facile strategy is proposed to reduce the crystallinity difference between donor and acceptor by incorporating a novel multifunctional liquid crystal small molecule (LCSM) BDTPF4‐C6 into the binary blend. BDTPF4‐C6 is the first LCSM based on a tetrafluorobenzene unit and features a low liquid crystal phase transition temperature and strong self‐assembly ability, conducive to regulating the active layer morphology. When BDTPF4‐C6 is introduced as a guest molecule into the PM6 : Y6 binary, it exhibits better compatibility with the donor PM6 and primarily resides within the PM6 phase because of the similarity‐intermiscibility principle. Moreover, systematic studies revealed that BDTPF4‐C6 could be used as a seeding agent for PM6 to enhance its crystallinity, thereby forming a more balanced and favourable charge transport with suppressed charge recombination. Intriguingly, dual Förster resonance energy transfer was observed between the guest molecule and the host donor and acceptor, resulting in an improved current density. This study demonstrates a facile approach to balance the charge mobilities and offers new insights into boosting the efficiency of single‐junction OSCs beyond 20 %. [ABSTRACT FROM AUTHOR]

Incorporation of siloxane-functionalized units into polymers backbone has proven to be an efficient strategy to improve photovoltaic performance. In this work, a low-cost siloxane-containing unit was developed to construct a series of terpolymers, and the effects of siloxane on the polymer performance were systematically studied. Different contents of thiophene containing siloxane-functionalized side chain were introduced into PM6 to obtain a series of polymers (PM6, PM6-SiO-10, PM6-SiO-20 and PM6-SiO-30). The siloxane-functionalized side chains in polymers have only a slight effect on the absorption behavior and frontier molecular orbitals. However, when the siloxane content increased, the terpolymers' aggregation property decreased and the temperature-dependency increased, leading to improved donor-acceptor compatibility. The power conversion efficiency (PCE) based on PM6:Y6, PM6-SiO-20:Y6 and PM6-SiO-30:Y6 devices was 15.64%, 16.03% and 15.82%, respectively. In comparison, the active layer based on PM6-SiO-10:Y6 exhibits the most appropriate phase separation morphology, resulting in effective exciton dissociation, more balanced hole-electron transport and less recombination. Consequently, the highest PCE of 16.69% with an outstanding short-circuit current density of 26.96 mA·cm−2 was obtained, which are one of the highest values for siloxane-functionalized polymer-based devices. This work demonstrates that finely controlling the content of siloxane-functionalized thiophene is beneficial for obtaining high-performance terpolymer donors and provides a novel and low-cost method to improve photovoltaic performance. [ABSTRACT FROM AUTHOR]

The morphology of the active layer plays a crucial role in the device performance and stability of organic solar cells (OSCs). To obtain the optimized blend film morphology, numerous solvent additives have been developed and utilized. Nevertheless, the commonly used high boiling point solvent additives have strict volume control and residual problems, which are not conducive to the development of OSCs. To alter the situation, it is urgent to develop highly volatile additives to minimize the unfavorable effect. Here, a volatile aromatic small molecule, benzoylacetate (BA), is used as a solid additive to control the morphology of the active layer during the post-treatment procedure. More importantly, BA has an apparent positive interaction with Y6, leading to more favorable molecular arrangement in the blend film and enhanced charge transfer properties. Finally, the BA-treated PM6:Y6 device exhibits improved device performance and photostability. Moreover, BA could be used as a universal solid additive for different OSC systems. Specifically, a superior PCE of 18.5 % is achieved in BA-processed PM6:L8-BO binary system with good photostability. Our work demonstrates an approach of applying a volatile solid additive to improve the device performance and photostability. [Display omitted] • High-performance organic solar cells (OSCs) were fabricated by introducing benzoylacetone (BA), a volatile aromatic small molecule, into the non-fullerene acceptor (NFA) systems. • The addition of BA can be used to control the blend morphology and obtain improved crystallinity and appropriate phase separation. Meanwhile, good volatility of BA is beneficial to improve the photostability of OSCs. • For the binary PM6:L8-BO device, a notable PCE of 18.5 % was yielded after treatment with the BA additive, which is much higher than that of the device treated with DIO. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Narrow‐bandgap n‐type polymers are essential for advancing the development of all‐polymer solar cells (all‐PSCs). Herein, we developed a novel polymer acceptor PNT with π‐extended 2‐(3‐oxo‐2,3‐dihydro‐1H‐cyclopenta[b]naphthalen‐1‐ylidene) malononitrile (CPNM) end groups. Compared to commonly used 2‐(3‐oxo‐2,3‐dihydro‐1H‐cyclopenta[b]naphthalen‐1ylidene) malononitrile (IC) units, CPNM units have a further extended fused ring, providing the PNT polymer with extended absorption into the near‐IR region (903 nm) and exhibiting a narrow optical bandgap (1.37 eV). Furthermore, PNT exhibits a high electron mobility (6.79 × 10−4 cm2·V−1·S−1) and a relatively high‐lying lowest unoccupied molecular orbital (LUMO) energy level of −3.80 eV. When blended with PBDB‐T, all‐PSC achieves a power conversion efficiency (PCE) of 13.7% and a high short‐circuit current density (JSC) of 24.4 mA·cm−2, mainly attributed to broad absorption (600—900 nm) and efficient charge separation and collection. Our study provides a promising polymer acceptor for all‐PSCs and demonstrates that π‐extended CPNM units are important to achieve high‐performance for all‐PSCs. [ABSTRACT FROM AUTHOR]

Mullins effect of carbon black filled nitrile butadiene rubber compounds and vulcanizates during cyclic tensile deformation is investigated and the influences of thermal annealing of the stretched samples, the deformation velocity and history and the solvent swelling are discussed. The energy losses associated with recovery hysteresis and softening accompanying the Mullins effect at a given crosshead velocity are quantitatively analyzed. The results show that the recovery hysteresis involves in microscopic deformation of the rubber phase in the nanocomposites but it disappears in the swollen samples. On the other hand, the softening is associated with both the rubber and filler phases; its energy loss increases with increasing filler content and decreases significantly by swelling. Furthermore, the softening of samples stretched at room temperatures is recoverable after conditioning at 80 °C but the recovery is retarded significantly by filler. The investigation allows gaining recognition of the important role played by the viscoelastic rubber matrix and the influence of the filler. Image 1 • The energy loss accompanying Mullins effect is decomposed into recovery hysteresis and softening parts. • The recovery hysteresis involves in deformation of the viscoelastic rubber phase and disappears after swelling. • The softening is associated with both the rubber and filler phases. • The softening of stretched vulcanizates is recoverable during annealing at elevated temperatures and is retarded by filler. [ABSTRACT FROM AUTHOR]

Reducing non‐radiative recombination energy loss (ΔE3) is one key to boosting the efficiency of organic solar cells. Although the recent studies have indicated that the Y‐series asymmetric acceptors‐based devices featured relatively low ΔE3, the understanding of the energy loss mechanism derived from molecular structure change is still lagging behind. Herein, two asymmetric acceptors named BTP‐Cl and BTP‐2Cl with different terminals were synthesized to make a clear comparative study with the symmetric acceptor BTP‐0Cl. Our results suggest that asymmetric acceptors exhibit a larger difference of electrostatic potential (ESP) in terminals and semi‐molecular dipole moment, which contributes to form a stronger π–π interaction. Besides, the experimental and theoretical studies reveal that a lower ESP‐induced intermolecular interaction can reduce the distribution of PM6 near the interface to enhance the built‐in potential and decrease the charge transfer state ratio for asymmetric acceptors. Therefore, the devices achieve a higher exciton dissociation efficiency and lower ΔE3. This work establishes a structure‐performance relationship and provides a new perspective to understand the state‐of‐the‐art asymmetric acceptors. [ABSTRACT FROM AUTHOR]

Introduction: Unbiased metagenomic next-generation sequencing (mNGS) has been used for infection diagnosis. In this study, we explored the clinical diagnosis value of mNGS for pulmonary complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Methods: From August 2019 to June 2021, a prospective study was performed to comparatively analyze the pathogenic results of mNGS and conventional tests for bronchoalveolar lavage fluid (BALF) from 134 cases involving 101 patients with pulmonary complications after allo-HSCT. Results: More pathogens were identified by mNGS than with conventional tests (226 vs 120). For bacteria, the diagnostic sensitivity (P = 0.144) and specificity (P = 0.687) were similar between the two methods. For fungus except Pneumocystis jirovecii (PJ), conventional tests had a significantly higher sensitivity (P = 0.013) with a similarly high specificity (P = 0.109). The sensitivities for bacteria and fungi could be increased with the combination of the two methods. As for PJ, both the sensitivity (100%) and specificity (99.12%) of mNGS were very high. For viruses, the sensitivity of mNGS was significantly higher (P = 0.021) and the negative predictive value (NPV) was 95.74% (84.27–99.26%). Pulmonary infection complications accounted for 90.30% and bacterium was the most common pathogen whether in single infection (63.43%) or mixed infection (81.08%). The 6-month overall survival (OS) of 88.89% in the early group (mNGS ≤ 7 days) was significantly higher than that of 65.52% (HR 0.287, 95% CI 0.101–0.819, P = 0.006) in the late group (mNGS > 7 days). Conclusions: mNGS for BALF could facilitate accurate and fast diagnosis for pulmonary complications. Early mNGS could improve the prognosis of patients with pulmonary complications after allo-HSCT. Trial Registration: ClinicalTrials.gov identifier, NCT 04051372. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) organic photodetectors (OPDs) are competitive candidates for flexible electronics in biomedical imaging and optical communications applications. However, current OPDs still suffer from a low detectivity beyond 1000 nm and a high dark current at bias due to the lack of high‐performance narrow‐bandgap non‐fullerene acceptors (NFAs). In this study, spiro‐conjugated core donor (D) unit is adopted to construct NFAs, SPT‐4F and tSPT‐4F. Comparing with PT‐4F without spiro‐conjugation, the orthogonal spiro‐conjugated planes endow SPT‐4F and tSPT‐4F with more rigid conformation and thus superior intermolecular stacking, resulting in the enhanced absorption beyond 1000 nm. Impressively, tSPT‐4F based device gives the best performance with a dark current of 4.52 × 10−10 A cm−2 under reversed bias of −0.1 V, an external quantum efficiency (EQE) response over 48% at 1010 nm, a detectivity of 1.25 × 1013 Jones and a responsibility of 0.40 A W−1 at 1010 nm. To the best of the authors' knowledge, this is one of the best performed devices reported to date for binary NIR OPDs with response beyond 1000 nm. This study provides a feasible molecular design strategy to develop narrow‐bandgap NFAs with spiro‐conjugation for highly detective NIR OPDs. [ABSTRACT FROM AUTHOR]

Highlights: A solid additive-assisted layer-by-layer (SAA-LBL) processing was developed to facilitate the inter-diffusion between polymer donor and acceptor and optimize the morphology of quasi-planar heterojunction for high-performance organic solar cells (OSCs). The pre-phase separation between fatty acid and polymer donor, easily tuned via controlling the cohesive energy, is critical to form the desired vertical phase-separation morphology. The SAA-LBL is generally applicable to various OSC systems, and enables the record efficiency of 19.02% among the binary OSCs. Morphology is of great significance to the performance of organic solar cells (OSCs), since appropriate morphology could not only promote the exciton dissociation, but also reduce the charge recombination. In this work, we have developed a solid additive-assisted layer-by-layer (SAA-LBL) processing to fabricate high-efficiency OSCs. By adding the solid additive of fatty acid (FA) into polymer donor PM6 solution, controllable pre-phase separation forms between PM6 and FA. This intermixed morphology facilitates the diffusion of acceptor Y6 into the donor PM6 during the LBL processing, due to the good miscibility and fast-solvation of the FA with chloroform solution dripping. Interestingly, this results in the desired morphology with refined phase-separated domain and vertical phase-separation structure to better balance the charge transport /collection and exciton dissociation. Consequently, the binary single junction OSCs based on PM6:Y6 blend reach champion power conversion efficiency (PCE) of 18.16% with SAA-LBL processing, which can be generally applicable to diverse systems, e.g., the PM6:L8-BO-based devices and thick-film devices. The efficacy of SAA-LBL is confirmed in binary OSCs based on PM6:L8-BO, where record PCEs of 19.02% and 16.44% are realized for devices with 100 and 250 nm active layers, respectively. The work provides a simple but effective way to control the morphology for high-efficiency OSCs and demonstrates the SAA-LBL processing a promising methodology for boosting the industrial manufacturing of OSCs. [ABSTRACT FROM AUTHOR]

All‐polymer solar cells (all‐PSCs) have achieved impressive progress in photovoltaic performance and stabilities recently. However, their power conversion efficiencies (PCEs) still trail that of small‐molecular acceptor‐based organic solar cells (>19%) mainly because of the inferior fill factor (FF). Herein, a combined homo hydrocarbon solvent and sequential deposition (SD) strategy is presented to boost the FF of rigid all‐PSCs to 77.7% and achieve a superior PCE of 17.7% with excellent stability, which is among the highest efficiencies reported for all‐PSCs thus far. Meanwhile, a remarkable PCE of 14.5% is realized for flexible all‐PSCs with outstanding mechanical stability. The blend film morphologies measurements suggest that the SD method enables the formation of an ideal pseudo‐bilayer film with bicontinuous interdigitated structure and ordered polymer packing. The numerical simulation result indicates that the FF enhancement mainly results from the efficient exciton diffusion dynamics, increased carrier mobilities, and more balanced electron/hole mobility ratio induced by the developed SD method. This is also confirmed by the FF loss analysis, which manifests that the reduced series resistance and increased shunt resistance are the main reasons for the reduction of FF loss. This work provides a promising strategy to fabricate highly efficient and stable all‐PSCs to promote their future development and practical manufacturing. [ABSTRACT FROM AUTHOR]

To investigate the influence of thiophene-fused indanone or thieno[3,2- b ]thiophene-fused indanone on acceptors, we designed and synthesized three molecules BTP-CC, BTP-TTC and BTP-TC. Impressively, a high open-circuit voltage (V oc) of 0.98 V was achieved in BTP-CC based device, which is one of the highest values based on A-DA′D-A type acceptors to date. The small Î" E HOMO (0.05 eV) between PBDB-T and BTP-TTC resulted in the inefficient exciton dissociation and charge transfer. Despite obtaining a relatively high V oc of 0.95 V, BTP-TTC based organic solar cell (OSC) displayed poor short-circuit current density (J sc) and efficiency. Compared with BTP-CC and BTP-TTC, BTP-TC exhibited red-shifted absorption and down-shifted energy levels. Benefiting from the increased crystallinity and the stronger intermolecular interaction, the device of PBDB-T:BTP-TC achieved improved charge dissociation, enhanced charge transport and suppressed charge recombination. Eventually, BTP-TC based OSC realized a higher efficiency of 13.57% with V oc of 0.86 V, J sc of 22.64 mA cmâ€"2 and fill factor of 0.70. This systematic work provides an approach to improving V oc and establishes a guideline for developing A-DA′D-A type acceptors with thiophene- or thieno[3,2- b ]thiophene-containing end group. [ABSTRACT FROM AUTHOR]

Developing non‐fullerene acceptors (NFAs) with strong absorption and optical response in near‐infrared region (NIR) is an imperative avenue for achieving efficient organic solar cells (OSCs) and NIR organic photodetectors (OPDs). Herein, four ultra‐narrow bandgap NFAs with different alkyl side chains and 2D fluorinated or non‐fluorinated phenyl substituents using dithienopyrrolecarbazole as electron‐rich core are designed and synthesized for photoelectric devices. The effect of 2D central core fluorination on molecular self‐assembly and optoelectronic properties is comprehensively explored. Due to the banana‐type molecular conformation of these NFAs, they can easily form honeycomb‐like 3D network stacking, and the central core fluorination is confirmed that can reduce ππ stacking distance and enhance intermolecular interaction, which result in smaller molecular stacking density. As a result, the 2D fluorinated acceptors based OSCs display more balanced and higher carrier mobilities, contributing to higher fill factor and efficiency. Moreover, the NIR OPD devices based on PTB7‐Th:FDTPC‐OD exhibit a superior responsivity of >0.4 A W−1 at 880 nm, a low dark current of ≈8 × 10–11 A, and an excellent specific detectivity (D*) of >2.5 × 1011 Jones. The NIR OPD also demonstrates excellent performance in photo‐plethysmography and shows great potential for application in monitoring heart rate. [ABSTRACT FROM AUTHOR]

Parvovirus B19 (PvB19) infection and PvB19 related pure red cell aplasia (PRCA) in recipients with allogeneic hematopoietic stem cell transplantation have been reported sporadically. However, clinical studies with large sample sizes are lacking, especially in patients undergoing HLA-haploidentical peripheral blood stem cell transplantation (haplo-PBSCT). In addition, clinical features, immune reconstitution, and outcomes of these patients are not clear. We conducted a retrospective analysis of 164 patients who received haplo-PBSCT with low-dose anti-thymocyte globulin (ATG) plus low-dose posttransplant cyclophosphamide (PTCy)-based regimen as graft-versus-host disease (GVHD) prophylaxis. We analyzed the incidence of PvB19 related PRCA and compared the clinical characteristics, immune reconstitution, incidence of GVHD, relapse rate, and survival between patients with and without PvB19 related PRCA. A total of 14 (8.5%) recipients developed PvB19 related PRCA after a median of 5.3 months after haplo-PBSCT. These patients with PvB19 related PRCA had slower immune reconstitution, but similar incidences of GVHD, relapse rate, and overall survival compared with recipients without PvB19 related PRCA. PvB19 related PRCA indicated relative delayed and poor immune reconstitution of the recipients early after haplo-PBSCT. PvB19 related PRCA had no effects on GVHD, relapse, and survival. [ABSTRACT FROM AUTHOR]

Ti 3 AlC 2 ceramic exhibits potential in Ag-based composite electrical contact materials, but its interface characteristic with Ag matrix remains unexplored. In this work, sessile drop experiment is carried out to investigate the high-temperature wetting behavior of molten Ag with Ti 3 AlC 2. Stable Ti 3 AlC 2 is hardly wetted by molten Ag below 1000 °C(contact angle of 148.5°), but the wettability of Ag/Ti 3 AlC 2 improves with the increasing temperature(final 14° at ∼1130 °C). In contrast, the Ti 3 C 2, a MXene with Al layer removed from its parent Ti 3 AlC 2 , exhibits inferior wettability with Ag(final 56.5° at ∼1130 °C). Wetting mechanism of Ag/Ti 3 AlC 2 is proposed on the basis of the interfacial structure and chemical composition. Increasing temperature accelerates dissociation of Ti 3 AlC 2 , and outward-escaping Al reacts with Ag to form interface layer with a composition of Ag 4.86 Ti 8.66 AlC 7.59 , Ag also diffuses along Ti 3 AlC 2 grain boundaries and forms gradient reactive products(Ag–Ti–Al–C), which promotes their wettability. Finally comprehensive properties of Ag/Ti 3 AlC 2 and Ag/Ti 3 C 2 are compared. Al–Ag interdiffusion slightly decreases the electrical conductivity of Ag/Ti 3 AlC 2 bulk material, but strengthen the interface bonding of composite and promote the viscosity of the molten pool, leading to the superior mechanical and anti-arc erosion properties. Absence of Al–Ag interdiffusion does remarkably improve the electrical conductivity of Ag/Ti 3 C 2 bulk materials, but lack of Al layer damages the mechanical core and wettability with Ag, resulting in a drastic decrease of anti-arco erosion property. [ABSTRACT FROM AUTHOR]

We examined how Raoultella ornithinolytica-ZK4 degraded pyrethroid pesticides within soil sediment from an abandoned pesticide plant. Lambda-cypermethrin and deltamethrin are two pyrethroid insecticides with high insecticidal activity and a wide range of applications. However, their increased use has raised concerns regarding toxicity and accumulation. We isolated a strain of ZK4 (Raoultella ornithinolytica-ZK4) from soil taken from a channel that surrounded a pesticide plant. We used enzyme localization to study degrading bacteria ZK4. The ZK4 strain underwent intracellular enzyme degradation. The degradation rates of lambda-cyhalothrin and deltamethrin were 55% and 53%, respectively. The optimum pH of the two kinds of pyrethroids in ZK4 was 6.5, and their optimum temperature was 37 °C. The intracellular degradation of the crude enzyme produced by the ZK4 strain had a pH of 6.0–8.0 and a temperature of 20–42 °C. The ZK4 strain genome contained 5310 genes with a total length of 4,864,494 bp. Sugar metabolism and exogenous chemical metabolism accounted for the largest proportion of metabolic activities. We used the clusters of orthologous groups (COG) alignment and found numbers for 4686 protein sequences, accounting for 88.25% of the total predicted protein. ZK4 degraded lambda-cyhalothrin and deltamethrin, and may serve as a reference for the preparation of future degrading microbial agents to assist with environmental restoration efforts. [ABSTRACT FROM AUTHOR]

Deltamethrin is a pyrethroid insecticide with high insecticidal activity and a wide range of applications. However, with the increased amount and scope of its application, the accumulated toxicity of deltamethrin has gradually raised concerns. In this study, a bacterium strain, which used deltamethrin as its sole carbon source and was named ZJ6 (Lysinibacillus sp.-ZJ6), was isolated from soil samples collected from the sewage outlet of a pesticide plant in Tianjin. Based on morphological observations of ZJ6, as well as its physiological and biochemical characteristics and 16S rDNA sequence (Gen Bank Accession No. KU129013), the strain was identified as Lysinibacillus fusiformis sp.. A study of the degradation characteristics of ZJ6 revealed that the optimum conditions for shake flask fermentation to degrade deltamethrin by ZJ6 were as follows: pH 7.0, a temperature of 30 °C, a substrate concentration of 100-200 mg/L, an inoculation volume of 10%, and 7 days culturing at 160 rpm. Under these conditions, the degradation rate of deltamethrin by ZJ6 reached 57.2%. Preliminary sequencing of the ZJ6 genome showed that it has a total length of 3,921,852 bp and contains 4567 genes. The average length of each gene in the ZJ6 genome is 859 bp, and these genes account for 84.62% of the total genome length. KEGG metabolic pathway analysis revealed that genes involved in sugar metabolism and metabolism of exogenous chemical substances were significantly enriched in the genome of ZJ6. Comparison with the COG database showed that 2839 of the predicted protein sequences from the ZJ6 genome had COG numbers. Among all protein functions, the number of genes involved in general functions was the highest (372). For the first time, it was found that ZJ6 has relatively strong deltamethrin degradation ability and high value as a subject for further research. In addition, this study provides a reference to guide the preparation of pesticide-degrading bacterial agents and environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of 1D/2A type novel wide-bandgap terpolymer donors were synthesized. • Using a simple and low-cost electron-deficient building block DTCPz to develop terpolymers. • The hero PSC presents a particularly increased PCE of 17.8%, with ca. 11% of improvement from that of 16.0% for the parent PM6-based ones. • Our terpolymer strategy provides a positive effect on improving the thermal stability of the device. It had been commonly accepted in the organic photovoltaic (OPV) community that subtle variations in the molecular structure of active layer materials would cause profound impacts on their aggregating structure and blend morphology and therefore the performance of such polymer solar cells (PSCs). Herein, we employed an electron-deficient building block 3,6-dithiophenyl-2-carboxylate pyrazine (DTCPz) for constructing one series of promising donor terpolymers of PMZ1, PMZ2, and PMZ3, respectively, gaining their relatively lower-lying highest occupied molecular orbital (HOMO) energy levels, more closed π-π stacking and enhanced crystallinity in thin films, and lower miscibility with acceptor Y6, in comparison with their parent polymer counterpart (namely PM6). Reaching DTCPz moieties up to 20% (mol/mol%) in its terpolymer composition, the resulting polymer (PMZ2) achieved more favorable phase separation with improved exciton dissociation, and charge transport and extraction. As a result, an outstanding fill factor of 77.2% and a promising power conversion efficiency of 17.8 % was achieved. Moreover, the corresponding device shows better thermal stability over the PM6-based one. This work suggests a facile method for significantly improving the thin film morphology of the active-layer materials via fine-tuning the chemical structure of electron-deficient units on the backbone of the wide bandgap donor polymer, therefore achieving enhanced photovoltaic performance and thermal stability for practical applications. [ABSTRACT FROM AUTHOR]

Cytosine base editing is a powerful tool for making precise single nucleotide changes in cells and model organisms like zebrafish, which are valuable for studying human diseases. However, current base editors struggle to edit cytosines in certain DNA contexts, particularly those with GC and CC pairs, limiting their use in modelling disease-related mutations. Here we show the development of zevoCDA1, an optimized cytosine base editor for zebrafish that improves editing efficiency across various DNA contexts and reduces restrictions imposed by the protospacer adjacent motif. We also create zevoCDA1-198, a more precise editor with a narrower editing window of five nucleotides, minimizing off-target effects. Using these advanced tools, we successfully generate zebrafish models of diseases that were previously challenging to create due to sequence limitations. This work enhances the ability to introduce human pathogenic mutations in zebrafish, broadening the scope for genomic research with improved precision and efficiency., (© 2024. The Author(s).)

Polymers with high viscosity and good viscosity-temperature property have attracted attention as chemical agents for enhanced oil recovery. The role of polymers in the emulsifying stability of an amphoteric polyacrylamide (TSPAM) with good viscosity-temperature property in different flooding systems was investigated by means of a new emulsion stability model and molecular simulations. The results indicated that TSPAM exhibited superior emulsion stability compared to hydrolyzed polyacrylamide (HPAM). The half-life of emulsions containing TSPAM was 1-7 min longer than that of emulsions containing HPAM. The results of molecular simulation revealed that the HPAM molecules adsorbed at the oil-water interface in a "point adsorption" mode, whereas the TSPAM molecules adsorbed in a "surface adsorption" mode, resulting in higher interfacial adsorption efficiency and more stable interfacial film. The polymer flooding systems containing TSPAM showed a larger interfacial thickness of 1.029 nm and higher emulsification efficiency compared to the polymer flooding systems containing HPAM. The addition of Na 2 CO 3 or surfactants further improved the stability of emulsions in the binary systems containing TSPAM. The stability of emulsions containing all three oil displacement agents was the strongest, with the half-life extended by 3.8-13.6 min. Amphoteric polyacrylamide significantly enhanced the stability of the emulsions. Through the integration of experimental and molecular simulation techniques, the molecular structure of polyacrylamide can be optimized, facilitating the development of more efficient oil recovery formulations for enhanced oil recovery applications., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

It is highly desired yet challenging to develop advanced elastomers with excellent mechanical properties, including high strength and toughness. In this work, strong and tough rubber/rubber compound vulcanizates were facilely prepared by blending ethylene-propylene-methylene (EPM) and isoprene rubber (IR) together with dicumyl peroxide (DCP) and subsequent vulcanization, since both EPM and IR can be vulcanized synchronously by DCP and the well-crosslinked structure of EPM/IR vulcanizate presented a stable phase separation state. By tuning their composition, EPM/IR vulcanizates could present remarkably improved mechanical strength and toughness, as well as excellent energy dissipation and deformation recovery abilities. Furthermore, EPM/IR/SiO 2 nanocomposites with better properties were prepared by introducing silica nanoparticles into EPM/IR vulcanizates. It was found that the high toughness and strength of EPM/IR vulcanizates and EPM/IR/SiO 2 nanocomposites mainly resulted from the combination of stretchability of EPM and strain hardening of IR. Their excellent energy dissipation and deformation recovery abilities were related to the macromolecular characteristics of EPM and IR, compatibility between EPM and IR, and their crosslinking dynamics.

Although a suitable vertical phase separation (VPS) morphology is essential for improving charge transport efficiency, reducing charge recombination, and ultimately boosting the efficiency of organic solar cells (OSCs), there is a lack of theoretical guidance on how to achieve the ideal morphology. Herein, a relationship between the molecular structure and the VPS morphology of pseudo-planar heterojunction (PPHJ) OSCs is established by using molecular surface electrostatic potential (ESP) as a bridge. The morphological evolution mechanism is revealed by studying four binary systems with vary electrostatic potential difference (∆ESP) between donors (Ds) and acceptors (As). The findings manifest that as ∆ESP increases, the active layer is more likely to form a well-mixed phase, while a smaller ∆ESP favors VPS morphology. Interestingly, it is also observed that a larger ∆ESP leads to enhanced miscibility between Ds and As, resulting in higher non-radiative energy losses (ΔE 3 ). Based on these discoveries, a ternary PPHJ device is meticulously designed with an appropriate ∆ESP to obtain better VPS morphology and lower ΔE 3 , and an impressive efficiency of 19.09% is achieved. This work demonstrates that by optimizing the ΔESP, not only the formation of VPS morphology can be controlled, but also energy losses can be reduced, paving the way to further boost OSC performance., (© 2024 Wiley‐VCH GmbH.)

This study aims to identify dynamic patterns within the spatiotemporal feature space that are specific to nonpsychotic major depression (NPMD), psychotic major depression (PMD), and schizophrenia (SCZ). The study also evaluates the effectiveness of machine learning algorithms based on these network manifestations in differentiating individuals with NPMD, PMD, and SCZ. A total of 579 participants were recruited, including 152 patients with NPMD, 45 patients with PMD, 185 patients with SCZ, and 197 healthy controls (HCs). A dynamic functional connectivity (DFC) approach was employed to estimate the principal FC states within each diagnostic group. Incremental proportions of data (ranging from 10% to 100%) within each diagnostic group were used for variability testing. DFC metrics, such as proportion, mean duration, and transition number, were examined among the four diagnostic groups to identify disease-related neural activity patterns. These patterns were then used to train a two-layer classifier for the four groups (HC, NPMD, PMD, and SCZ). The four principal brain states (i.e., states 1,2,3, and 4) identified by the DFC approach were highly representative within and across diagnostic groups. Between-group comparisons revealed significant differences in network metrics of state 2 and state 3, within delta, theta, and gamma frequency bands, between healthy individuals and patients in each diagnostic group (p < 0.01, FDR corrected). Moreover, the identified key dynamic network metrics achieved an accuracy of 73.1 ± 2.8% in the four-way classification of HC, NPMD, PMD, and SCZ, outperforming the static functional connectivity (SFC) approach (p < 0.001). These findings suggest that the proposed DFC approach can identify dynamic network biomarkers at the single-subject level. These biomarkers have the potential to accurately differentiate individual subjects among various diagnostic groups of psychiatric disorders or healthy controls. This work may contribute to the development of a valuable EEG-based diagnostic tool with enhanced accuracy and assistive capabilities., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Additive engineering is widely utilized to optimize film morphology in active layers of organic solar cells (OSCs). However, the role of additive in film formation and adjustment of film morphology remains unclear at the molecular level. Here, taking high-efficiency Y6-based OSC films as an example, this work thus employs all-atom molecular-dynamics simulations to investigate how introduction of additives with different π-conjugation degree thermodynamically and dynamically impacts nanoscale molecular packings. These results demonstrate that the van der Waals (vdW) interactions of the Y6 end groups with the studied additives are strongest. The larger the π-conjugation degree of the additive molecules, the stronger the vdW interactions between additive and Y6 molecules. Due to such vdW interactions, the π-conjugated additive molecules insert into the neighboring Y6 molecules, thus opening more space for relaxation of Y6 molecules to trigger more ordered packing. Increasing the interactions between the Y6 end groups and the additive molecules not only accelerates formation of the Y6 ordered packing, but also induces shorter Y6-intermolecular distances. This work reveals the fundamental molecular-level mechanism behind film formation and adjustment of film morphology via additive engineering, providing an insight into molecular design of additives toward optimizing morphologies of organic semiconductor films., (© 2023 Wiley-VCH GmbH.)

Alcoholic liver disease (ALD) is primarily caused by long-term excessive alcohol consumption. Cyanidin-3-O-glucoside (C3G) is a widely occurring natural anthocyanin with multiple biological activities. This study aims to investigate the effects of C3G isolated from black rice on ALD and explore the potential mechanism. C57BL/6J mice (male) were fed with standard diet (CON) and Lieber-DeCarli liquid-fed (Eth) or supplemented with a 100 mg/kg/d C3G Diet (Eth-C3G), respectively. Our results showed that C3G could effectively ameliorate the pathological structure and liver function, and also inhibited the accumulation of liver lipids. C3G supplementation could partially alleviate the injury of intestinal barrier in the alcohol-induced mice. C3G supplementation could increase the abundance of Norank&#95;f&#95;Muribaculaceae , meanwhile, the abundances of Bacteroides , Blautia , Collinsella , Escherichia-Shigella , Enterococcus , Prevotella , [Ruminococcus]&#95;gnavus&#95;group , Methylobacterium-Methylorubrum , Romboutsia , Streptococcus , Bilophila , were decreased. Spearman's correlation analysis showed that 12 distinct genera were correlated with blood lipid levels. Non-targeted metabolic analyses of cecal contents showed that C3G supplementation could affect the composition of intestinal metabolites, particularly bile acids. In conclusion, C3G can attenuate alcohol-induced liver injury by modulating the gut microbiota and metabolites, suggesting its potential as a functional food ingredient against alcoholic liver disease.

Introduction: The novel low-dose anti-thymocyte (ATG, 5 mg/kg) plus low-dose post-transplant cyclophosphamide (PTCy, 50 mg/kg) (low-dose ATG/PTCy)-based regimen had promising activity for prevention of graft-versus-host disease (GVHD) in haploidentical-peripheral blood stem cell transplantation (haplo-PBSCT), but its impacts on long-term outcomes remain to be defined., Methods: We performed a large sample, long-term follow-up retrospective study to evaluate its efficacy for GVHD prophylaxis., Results: The study enrolled 260 patients, including 162 with myeloid malignancies and 98 with lymphoid malignancies. The median follow-up time was 27.0 months. For the entire cohort, the cumulative incidences (CIs) of grade II-IV and III-IV acute GVHD (aGVHD) by 180 days were 13.46% (95% CI, 9.64%-17.92%) and 5.77% (95% CI, 3.37%-9.07%); while total and moderate/severe chronic GVHD (cGVHD) by 2 years were 30.97% (95% CI, 25.43%-36.66%) and 18.08% (95% CI, 13.68%-22.98%), respectively. The 2-year overall survival (OS), relapse-free survival (RFS), GVHD-free, relapse-free survival (GRFS), non-relapse mortality (NRM), and CIs of relapse were 60.7% (95% CI, 54.8%-67.10%), 58.1% (95% CI, 52.2%-64.5%), 50.6% (95% CI, 44.8-57.1%), 23.04% (95% CI, 18.06%-28.40%), and 18.09% (95% CI, 14.33%-23.97%, respectively. The 1-year CIs of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) reactivation were 43.46% (95% CI, 37.39%-49.37%) and 18.08% (95% CI, 13.68%-22.98%), respectively. In multivariate analysis, the disease status at transplantation was associated with inferior survivor outcomes for all patients and myeloid and lymphoid malignancies, while cGVHD had superior outcomes for all patients and myeloid malignancies, but not for lymphoid malignancies., Discussion: The results demonstrated that the novel regimen could effectively prevent the occurrence of aGVHD in haplo-PBSCT., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Li, Yang, Cai, Huang, Xu, Qiu, Niu, Zhou, Zhang, Xia, Wei, Shen, Tong, Dong, Wan and Song.)

Background: Due to the lower reliability of laboratory tests, skin diseases are more suitable for diagnosis with AI models. There are limited AI dermatology diagnostic models combining images and text; few of these are for Asian populations, and few cover the most common types of diseases., Methods: Leveraging a dataset sourced from Asia comprising over 200,000 images and 220,000 medical records, we explored a deep learning-based system for Dual-channel images and extracted text for the diagnosis of skin diseases model DIET-AI to diagnose 31 skin diseases, which covers the majority of common skin diseases. From 1 September to 1 December 2021, we prospectively collected images from 6,043 cases and medical records from 15 hospitals in seven provinces in China. Then the performance of DIET-AI was compared with that of six doctors of different seniorities in the clinical dataset., Results: The average performance of DIET-AI in 31 diseases was not less than that of all the doctors of different seniorities. By comparing the area under the curve, sensitivity, and specificity, we demonstrate that the DIET-AI model is effective in clinical scenarios. In addition, medical records affect the performance of DIET-AI and physicians to varying degrees., Conclusion: This is the largest dermatological dataset for the Chinese demographic. For the first time, we built a Dual-channel image classification model on a non-cancer dermatitis dataset with both images and medical records and achieved comparable diagnostic performance to senior doctors about common skin diseases. It provides references for exploring the feasibility and performance evaluation of DIET-AI in clinical use afterward., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Li, Zhang, Wei, Qian, Tang, Hu, Huang, Xia, Zhang, Cheng, Yu, Zhang, Dan, Liu, Ye, He, Jiang, Liu, Fan, Song, Zhou, Wang, Zhang and Lv.)

Terpolymerization and regioisomerization strategies are combined to develop novel polymer donors to overcome the difficulty of improving organic solar cells (OSCs) performance. Two novel isomeric units, bis(2-hexyldecyl)-2,5-bis(4-chlorothiophen-2-yl)thieno[3,2-b]thiophene-3,6-dicarboxylate (TTO) and bis(2-hexyldecyl) 2,5-bis(3-chlorothiophen-2-yl)thieno[3,2-b]thiophene-3,6-dicarboxylate (TTI), are obtained and incorporated into the PM6 backbone via random copolymerization to form a series of terpolymers. Interestingly, it is found that different chlorine (Cl) substituent positions can significantly change the molecular planarity and electrostatic potential (ESP) owing to the steric hindrance effect of the heavy Cl atom, which leads to different molecular aggregation behaviors and miscibility between the donor and acceptor. The TTO unit features a higher number of multiple S···O non-covalent interactions, more positive ESP, and fewer isomer structures than TTI. As a result, the terpolymer PM6-TTO-10 exhibits a much better molecular coplanarity, stronger crystallinity, more obvious aggregation behavior, and proper phase separation in the blend film, which are conducive to more efficient exciton dissociation and charge transfer. Consequently, the PM6-TTO-10:BTP-eC9-based OSCs achieve a champion power conversion efficiency of 18.37% with an outstanding fill factor of 79.97%, which are among the highest values reported for terpolymer-based OSCs. This work demonstrates that terpolymerization combined with Cl regioisomerization is an efficient approach for achieving high-performance polymer donors., (© 2023 Wiley-VCH GmbH.)

High-performance all-polymer solar cells (all-PSCs) deeply rely on the joint contributions of desirable optical absorption, adaptive energy levels, and appropriate morphology. Herein, two structural analogous polymerized small-molecule acceptors (PSMAs), PYFCl-T and PYF&PYCl-T, are synthesized, and then incorporated into the PM6:PY-IT binary blends to construct ternary all-PSCs. Due to the superior compatibility of PY-IT and PYFCl-T, the ternary all-PSC based on PM6:PY-IT:PYFCl-T with 10 wt% PYFCl-T, presents higher and more balanced charge mobility, suppressed charge recombination, and faster charge-transfer kinetics, resulting in an outstanding power conversion efficiency (PCE) of 18.12% with enhanced J sc and FF, which is much higher than that (PCE of 16.09%) of the binary all-PSCs based on PM6:PY-IT. Besides, the ternary all-PSCs also exhibit improved photostability. The conspicuous performance enhancement principally should give the credit to the miscibility-driven phase optimization of the donor and acceptor. These findings highlight the significance of polymer-backbone configuration modulation of PSMAs in morphology optimization toward boosting the device properties of all-PSCs., (© 2023 Wiley-VCH GmbH.)

In the context of localization of Global Value Chain (GVC) and stricter carbon emission requirements, the impact of participating in GVC on carbon emission reduction has become one of the most crucial criteria for China's manufacturing industry to consider whether to deepen its participation in GVC. In order to clearly and directly reflect the change in the production distance between the original input and the final product, we use the GVC production length to express the degree of participation in GVC. And in order to make the research more targeted and typical, we select the equipment manufacturing industry as the research object. Using the data from the World Input-Output Database (WIOD), we empirically analyze the GVC production length under different cross-border production activities on the basis of the theoretical mechanism. The results show that the extension of the GVC production length can significantly promote the carbon emissions reduction. In the decomposition part, the extension of simple GVC production length can effectively promote carbon emissions reduction. Therefore, it is suggested that China's equipment manufacturing industry should continue to deeply participate in the high-end production links of GVC and improve its status in the complex GVC production activities., Competing Interests: Conflict of interestThe authors have no relevant financial or non-financial interests to disclose., (© The Author(s), under exclusive licence to Springer Nature B.V. 2022, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Inflammatory bowel disease (IBD) is a global chronic disease with a long duration and repeated relapse. Currently, there is still a lack of effective approaches to prevent IBD. Food-derived oryzanol (ORY) possesses extensive biological activities, such as ameliorating bowel diseases, antioxidation, and antiobesity. However, the mechanism of ORY in preventing colitis remains unclear. The present research aims to explore the potential mechanism of ORY in dextran sulfate sodium (DSS)-stimulated colitis in a rat model. The results showed that the symptoms of colitis were significantly improved with the administration of ORY. Mechanismly, the expression levels of Zonula occludens-1 (ZO-1), Claudin-1, Occludin, MUC2, and TFF3 were elevated through ORY treatment, suggesting that oral ORY relieved the degree of gut barrier damage of colitis rats. Meanwhile, 16S sequencing results found that ORY supplementation increased the abundances of Alloprevotella , Roseburia , Treponema , Muribaculaceae , and Ruminococcus , which are associated with the synthesis of short-chain fatty acids (SCFAs). Moreover, GC-MS results confirmed that ORY supplementation reversed the DSS-induced reduction of acetic acid, butyric acid, and total acid. Further research indicated that ORY intervention downregulated the TLR4/NF-κB/NLRP3 pathway, which is closely linked to the expression of proinflammatory cytokines and colon injury. Taken together, ORY ameliorates DSS-stimulated gut barrier damage and inflammatory responses via the gut microbiota-TLR4/NF-κB/NLRP3 signaling axis.

The development of hole-transport materials (HTMs) with high mobility, long-term stability, and comprehensive passivation is significant for simultaneously improving the efficiency and stability of perovskite solar cells (PVSCs). Herein, two donor-acceptor (D-A) conjugated polymers PBTI and PFBTI with alternating benzodithiophene (BDT) and bithiophene imide (BTI) units are successfully developed with desirable hole mobilities due to the good planarity and extended conjugation of molecular backbone. Both copolymers can be employed as HTMs with suitable energy levels and efficient defect passivation. Shortening the alkyl chain of the BTI unit and introducing fluorine atoms on the BDT moiety effectively enhances hole mobility and hydrophobicity of the HTMs, leading to improved efficiency and stability of PVSCs. As a result, the organic-inorganic hybrid PVSCs with PFBTI as the HTM deliver a power conversion efficiency (PCE) of 23.1% with enhanced long-term operational and ambient stability, which is one of the best efficiencies reported for PVSCs with dopant-free polymeric HTMs to date. Moreover, PFBTI can be applied in inorganic PVSCs and perovskite/organic tandem solar cells, achieving a high PCE of 17.4% and 22.2%, respectively. These results illustrate the great potential of PFBTI as an efficient and widely applicable HTM for cost-effective and stable PVSCs., (© 2022 Wiley-VCH GmbH.)

With the continuous breakthrough of the efficiency of organic photovoltaics (OPVs), their practical applications are on the agenda. However, the thickness tolerance and upscaling in recently reported high-efficiency devices remains challenging. In this work, the multiphase morphology and desired carrier behaviors are realized by utilizing a quaternary strategy. Notably, the exciton separation, carrier mobility, and carrier lifetime are enhanced significantly, the carrier recombination and the energy loss (E loss ) are reduced, thus beneficial for a higher short-circuit density (J SC ), fill factor (FF), and open-circuit voltage (V OC ) of the quaternary system. Moreover, the intermixing-phase size is optimized, which is favorable for constructing the thick-film and large-area devices. Finally, the device with a 110 nm-thick active layer shows an outstanding power conversion efficiency (PCE) of 19.32% (certified 19.35%). Furthermore, the large-area (1.05 and 72.25 cm 2 ) devices with 110 nm thickness present PCEs of 18.25% and 12.20%, and the device with a 305 nm-thick film (0.0473 cm 2 ) delivers a PCE of 17.55%, which are among the highest values reported. The work demonstrates the potential of the quaternary strategy for large-area and thick-film OPVs and promotes the practical application of OPVs in the future., (© 2022 Wiley-VCH GmbH.)

Power conversion efficiency and long-term stability are two critical metrics for evaluating the commercial potential of organic photovoltaics. Although the field has witnessed a rapid progress of efficiency towards 19%, the intrinsic trade-off between efficiency and stability is still a challenging issue for bulk-heterojunction cells due to the very delicate crystallization dynamics of organic species. Herein, we developed a class of non-fullerene acceptors with varied side groups as an alternative to aliphatic chains. Among them, the acceptors with conjugated side groups show larger side-group torsion and more twisted backbone, however, they can deliver an efficiency as high as 18.3% in xylene-processed cells, which is among the highest values reported for non-halogenated solvent processed cells. Meanwhile, decent thermal/photo stability is realized for these acceptors containing conjugated side groups. Through the investigation of the geometry-performance-stability relationship, we highlight the importance of side-group steric hinderance of acceptors in achieving combined high-performance, stable, and eco-friendly organic photovoltaics., (© 2022. The Author(s).)

This study analyzed genomic data of 4643 strains of carbapenemase-carrying Klebsiella pneumoniae (KPN) in China by using the Kleborate software package. The data showed rich diversity in carbapenemase-carrying KPN genomes, which contain not only 152 sequence types but also 90 capsular serotypes. In 2013, the transfer of carbapenemase to hypervirulent Klebsiella pneumoniae (HvKP) of KL1 and KL2 occurred, and since 2014, the propagation of carbapenemase into mammals, poultry, and insects has been detected. The ST11 capsular serotype had a reversal of the prevalence of KL47 and KL64 in 2016, with KL64 replacing KL47 as the dominant serotype. Colibactin is a very suitable indicator to differentiate KL1-type HvKP and classic Klebsiella pneumoniae. The most prevalent yersiniabactin of KL1 is ybt1 ICEKp10, and that of ST11 carbapenem-resistant KPN(ST11-CRKP) is ybt9 ICEKp3. The virulence genes of KL1 carbapenem-resistant hypervirulent KPN (KL1-CRHvKP), as well as ST65- and ST86-type KL2-CRHvKP, were not lost after carbapenemase was obtained.

Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://atm.amegroups.com/article/view/10.21037/atm-22-1498/coif). The authors have no conflicts of interest to declare.

Achieving high-performance as-cast OSCs is crucial for industrialization in the future, owing to the advantages of better stability, environmental-friendly, and decreasing production cost. In this regard, we synthesized an A-DA'D-A type acceptor, Y6-eC6-BO, by shortening the straight alkyl side-chains on the thiophene position from C 11 to C 6 as well as lengthening the branched alkyl side-chains on the pyrrole position of Y6 to achieve a stronger crystallization and better miscibility than Y6. As a result, the corresponding chloroform-processed as-cast PM6: Y6-eC6-BO OSC showed a high PCE of 17.33%, which was one of the highest efficiencies of as-cast OSCs. And the as-cast PM6:Y6-eC6-BO OSCs processed from o -xylene displayed a PCE of 16.38%, as far as we know, this is among the highest efficiencies of non-halogenated-solvent processed as-cast OSCs. These results demonstrated tailoring the alkyl side-chain of NFAs is a feasible and simple approach to achieve high performance as-cast OSCs and provides guideline in molecular design in the future., Competing Interests: The authors declare that they have no conflicts of interest in this work., (© 2022 The Authors. Publishing Services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.)

Graded bulk-heterojunction (G-BHJ) with well-defined vertical phase separation has potential to surpass classical BHJ in organic solar cells (OSCs). In this work, an effective G-BHJ strategy via nonhalogenated solvent sequential deposition is demonstrated using nonfullerene acceptor (NFA) OSCs. Spin-coated G-BHJ OSCs deliver an outstanding 17.48% power conversion efficiency (PCE). Depth-profiling X-ray photoelectron spectroscopy (DP-XPS) and angle-dependent grazing incidence X-ray diffraction (GI-XRD) techniques enable the visualization of polymer/NFA composition and crystallinity gradient distributions, which benefit charge transport, and enable outstanding thick OSC PCEs (16.25% for 300 nm, 14.37% for 500 nm), which are among the highest reported. Moreover, the nonhalogenated solvent enabled G-BHJ OSC via open-air blade coating and achieved a record 16.77% PCE. The blade-coated G-BHJ has drastically different D-A crystallization kinetics, which suppresses the excessive aggregation induced unfavorable phase separation in BHJ. All these make G-BHJ a feasible and promising strategy towards highly efficient, eco- and manufacture friendly OSCs., (© 2021. The Author(s).)

Unveiling the correlations among molecular structures, morphological characteristics, macroscopic properties and device performances is crucial for developing better photovoltaic materials and achieving higher efficiencies. To achieve this goal, a comprehensive study is performed based on four state-of-the-art non-fullerene acceptors (NFAs), which allows to systematically examine the above-mentioned correlations from different scales. It's found that extending conjugation of NFA shows positive effects on charge separation promotion and non-radiative loss reduction, while asymmetric terminals can maximize benefits from both terminals. Another molecular optimization is from alkyl chain tuning. The shortened alkyl side chain results in strengthened terminal packing and decreased π-π distance, which contribute high carrier mobility and finally the high charge collection efficiency. With the most-acquired benefits from molecular structure and macroscopic factors, PM6:BTP-S9-based organic photovoltaics (OPVs) exhibit the optimal efficiency of 17.56% (certified: 17.4%) with a high fill factor of 78.44%, representing the best among asymmetric acceptor based OPVs. This work provides insight into the structure-performance relationships, and paves the way toward high-performance OPVs via molecular design., (© 2021. The Author(s).)

Beryllium-doped boron clusters display essential similarities to borophene (boron sheet) with a molecular structure characterized by remarkable properties, such as anisotropy, metallicity and high conductivity. Here we have determined low-energy structures of BeB n 0/- (n = 10-20) clusters by utilizing CALYPSO searching program and DFT optimization. The results indicated that most ground states of clusters prefer plane or quasi-plane structures by doped Be atom. A novel unexpected fascinating planar BeB 16 - cluster with C 2v symmetry is uncovered which possesses robust relative stability. Furthermore, planar BeB 16 - offers a possibility to construct metallo-borophene nano-materials. Molecular orbital and chemical bonding analysis reveal the peculiarities of BeB 16 - cluster brings forth the aromaticity and the strong interaction of B-B σ-bonds in boron network.

There has been considerable research interest paid to rare-earth transition-metal-doped Y 3 Al 5 O 12 , which has great potential for application as a laser crystal of new-type laser devices because of its unique optoelectronic and photophysical properties. Here, we present new research conducted on the structural evolution and crystal-field characteristics of a rare-earth Nd-doped Y 3 Al 5 O 12 laser crystal by using the CALYPSO structure search method and our newly developed WEPMD method. A novel cage-like structure with a Nd 3+ concentration of 4.16% is uncovered, which belongs to the standardized C 222 space group. Our results indicate that the impurity Nd 3+ ions are likely to substitute the Y 3+ at the central site of the host Y 3 Al 5 O 12 crystal lattice. The laser emission 4 F 3/2 → 4 I 11/2 occurring at 1077 nm is in accord with that of the experimental data. By introducing the proper correlation crystal field, three transitions, 4 G 5/2 → 4 I 9/2 , 4 F 7/2 → 4 I 9/2 , and 4 S 3/2 → 4 I 9/2 , are predicted to be good candidates for laser action. These findings can provide powerful guidelines for further experiments of rare-earth-metal-doped laser crystals.

Zirconium disilicide (ZrSi 2 ) has been investigated experimentally and theoretically for its structural and physical properties at high pressures. In situ compression experiments demonstrate that at low pressure, ZrSi 2 adopts the C49 structure (space group Cmcm), which persists up to 54.5 GPa at room temperature, and the unit cell of ZrSi 2 along b-axis is at least twice as compressible as along a- and c-axis. A bulk modulus of 170.0 ± 0.7 GPa ( K' 0 = 4) is derived from the compression experiment employing methanol-ethanol mixture as the pressure-transmitting medium. Diffraction line-width analysis suggests a yield strength of about 3.0 GPa for ZrSi 2 under high pressures at room temperature. The first-principles calculations mostly agree with the experimental results, such as mechanical and dynamic stability and elastic anisotropy ( K c > K a ≫ K b ). However, predicted axial modulus K b by modeling is significantly smaller than the experimentally determined value, resulting in a sizable discrepancy between experimental (170.0 GPa) and theoretical (121.0 GPa) bulk moduli.

As an extension of boron based materials, transition-metal doped boron clusters deserve interest in controlling size-dependent structural and electronic properties. Herein, using the Crystal structure AnaLYsis by Particle Swarm Optimization (CALYPSO) method and density functional theory (DFT) calculations, we have performed a global search for the lowest-energy structures of ZrBQn (Q = 0, -1) clusters with n = 10-20. The results show that the ground-state structures of the obtained clusters feature a distinctive structural evolution pattern, from half-sandwich bowl to distorted drum-like and then to Zr-centered distorted tubular motifs. For the sake of validating the current ground-state structures, photoelectron spectra are predicted from time-dependent DFT calculations. More interestingly, the neutral and anionic ZrB12 clusters are found to possess enhanced stability in the size regime studied here. The stability of the closed shell half-sandwich ZrB12 cluster is analyzed by intrinsic bond orbital (IBO) and Adaptive Natural Density Partitioning (AdNDP) methods, which indicates that the stability mechanism is caused by the dopant Zr atom breaking the boron bowl's triangle B3 unit to form a quasi-linear B3 unit in B12 and strengthen both the interaction of the B-B σ-bonds and the Zr-B π-bonds.

Understanding the structural evolution of materials is a challenging problem of condensed matter physics. Solving this problem would open new ways for understanding the behaviors of materials. In this context, we here report unbiased structure searches for a prototypical perovskite oxide, PbTiO 3 , based on the CALYPSO (Crystal structure AnaLYsis by Particle Swarm Optimization) method in conjunction with first-principles calculations. For the first time, we decipher the structure evolution of PbTiO 3 from a zero dimensional (0D) cluster to a two dimensional (2D) layered structure and in the end to a three dimensional (3D) bulk solid. Our unbiased structure search is successful in reproducing the cubic Pm3[combining macron]m and tetragonal P4mm phases of PbTiO 3 at ambient pressure. We also predict a new quasi-planar kite shape structure of the PbTiO 3 cluster, with C s symmetry and a surprisingly large HOMO-LUMO gap. Furthermore, by using this method, we predict that the 2D planar PbTiO 3 monolayer is unstable in the perpendicular direction and the 2D PbTiO 3 double layer is dynamically stable, with a hope that it can provide guidance to future synthesis of low dimensional perovskite oxides.

The structures and electronic properties of low-energy neutral and anionic Mg n (n = 3-20) clusters have been studied by utilizing a widely adopted CALYPSO structure searching method coupled with density functional theory calculations. A large number of low-energy isomers are optimized at the B3PW91 functional with the 6-311+G(d) basis set. The optimized geometries clearly indicate that a structural transition from hollow three-dimensional configurations to filled-cage-like structures occurs at n = 16 for both neutral and anionic clusters. Based on the anionic ground state structures, photoelectron spectra are simulated using time-dependent density functional theory (TD-DFT) and compared with experimental results. The good agreement validates that the current ground state structures, obtained from the symmetry-unconstrained searches, are true global minima. A detailed chemical bonding analysis distinctly indicates that the Mg 17 cluster is the first neutral locally π-aromatic homonuclear all-metal cluster, which perfectly satisfies Hückel's well-known 4N + 2 rule.