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We examine the effect of short sellers on corporate innovation. To establish causality, we use a policy experiment that exogenously removes the short-selling constraint for a randomly selected subsample of Russell 3000 firms. We find that innovation quality, value, and efficiency of treatment firms improve significantly more than those of control firms surrounding the policy shock. The exposure to patenting-related litigation initiated by short sellers is a plausible underlying mechanism through which short sellers discipline firm managers and enhance innovation. Our paper provides new insights into an unintended real effect of short sellers, specifically their improvement of technological innovation. (JELG14, G18, G34, K22, O31, O32)

Solid-state Li-ion batteries are recognized as highly promising energy storage devices due to their ability to overcome issues related to the inferior cycle life and potential risks of traditional liquid Li-ion batteries. However, developing solid-state electrolytes with fast Li-ion conductivity continues to be a major challenge. In this study, we present a family of quasi-solid-state electrolytes (QSSEs) synthesized by confining liquid electrolytes within a N-rich porous carbon sponge, exhibiting superior Li-ion conduction for solid-state battery applications. The N-rich porous carbon sponge was prepared by carbonizing ZIF-8 under an argon atmosphere, followed by the incorporation of organic liquid salt electrolytes into the pores and channels of the sponge to create composite QSSEs. Notably, the resulting composite QSSEs demonstrate exceptional Li-ion conduction at room temperature, with a record-high conductivity exceeding 10–2S cm–1and a remarkable Li+transference number of 0.75, along with a wide electrochemical stability window of 4.8 V. Furthermore, these composite QSSEs show significant potential for use in solid-state Li-ion batteries, delivering a specific capacity of 133 mAh g–1at 0.1 C and possessing a high Coulombic efficiency of 98.6%.

Steel slag (SS) accumulates unavoidably due to its complex and unstable composition, high production volumes, and limited value-added resource utilization. Single or multiple interface modifiers were proposed to enhance the properties of SS through high-speed dispersion, transforming its inherent hydrophilic and oleophobic characteristics into hydrophily and lipophilicity. The modification effects were innovatively assessed by observing the color changes of modified steel slag solutions following the dissolution-settlement equilibrium constant. This approach avoided human-induced errors and improved estimated accuracy in conformance with conventional methods such as oil absorption value, activation index, sedimentation volume, and lipophilicity. The hydrolysis of 3-aminopropyltriethoxysilane (KH) generated –Si(OH)3structure to form hydrogen or covalent bonds with active substances (OH groups) from SS. Concurrently, SS underwent encapsulation via Si–O–Si structure resulting from the dehydration of –Si(OH)3. The stearic acid coupling agent (SA), aluminate coupling agent (AC), and titanate coupling agent (TN) underwent chemical reactions with Ca(OH)2, Al(OH)3, and CaCO3in SS. The acidic SA primarily created stable chemical bonds and acted as a supplement due to its package, reducing surface activity and hydrophilicity while enhancing lipophilicity. Specifically, the optimal modification effect was obtained at 3 wt.% SA. Consequently, 3 wt.% SA was established as the benchmark for multiple modifiers and the most effective combination was 3 wt.% SA and 3 wt.% AC. Compared with a single interface modifier, SA corroded the SS surface to provide numerous active sites for further modification by KH, AC, or TN, resulting in a more densely packed structure. In addition, more organic groups on SS prevent the proximity of other particles from agglomerating to achieve dispersion and a synergistic modification, laying a theoretical foundation of SS in a new pathway for organic composite materials.

An efficient copper-catalyzed dearomative [3 + 2] annulation of indoles with 2-iodoacetic acid is developed. By employing Cu(OTf)2/2,2′-bis(2-oxazoline) as the catalyst and LPO as the oxidant, a series of indoline-fused butyrolactones were synthesized in moderate to good yields. The reaction features mild conditions, a broad substrate scope, and readily available starting materials. Furthermore, synthetic transformations of the products were conducted to demonstrate the practical utility of this reaction.

The advantages of ammonia as a hydrogen carrier have led to proposals for on-site hydrogen production through its decomposition. Rapid cold start of ammonia decomposition is crucial for applications such as ammonia-powered vehicles, but conventional heating methods are challenged by the high decomposition temperature of ammonia. In this study, we successfully achieved the rapid cold start of ammonia decomposition using Co nanoparticle catalysts driven by magnetic induction heating, demonstrating excellent catalytic performance and stability. The magnetic induction heating-driven ammonia decomposition system was integrated with a hydrogen fuel cell, proving its ability to achieve the cold start of ammonia decomposition within 10 s, as demonstrated by comparative experiments using 75% H2-25% N2from a gas cylinder as the control. This study provides a deeper understanding of hysteresis heating catalysis, promoting the practical use of ammonia as a hydrogen carrier for rapid hydrogen production in the energy industry.

Objective: The prognosis of glioblastoma is poor, and therapy-resistance is largely attributed to intratumor hypoxia. Hyperbaric oxygen (HBO) effectively alleviates hypoxia. However, the sole role of HBO in glioblastoma remains controversial. We previously reported that HBO can promote apoptosis, shorten protrusions, and delay growth of glioblastoma, but the molecular mechanism is unclear. We aimed to test candidate genes in HBO-exposed glioblastoma cells and to analyze their correlation with the survival of glioblastoma patients. Methods: Glioblastoma cell lines exposed to repetitive HBO or normobaric air (NBA) were collected for RNA isolation and microarray data analysis. GO analysis, KEGG pathway analysis and survival analysis of the differentially expressed genes (DEGs) were performed. Results: HBO not only inhibited hypoxia-inducing genes including CA9, FGF11, PPFIA4, TCAF2 and SLC2A12, but also regulated vascularization by downregulating the expression of COL1A1, COL8A1, COL12A1, RHOJ and FILIP1L, ultimately attenuated hypoxic microenvironment of glioblastoma. HBO attenuated inflammatory microenvironment by reducing the expression of NLRP2, CARD8, MYD88 and CD180. HBO prevented metastasis by downregulating the expression of NTM, CXCL12, CXCL13, CXCR4, CXCR5, CDC42, IGFBP3, IGFBP5, GPC6, MMP19, ADAMTS1, EFEMP1, PTBP3, NF1 and PDCD1. HBO upregulated the expression of BAK1, PPIF, DDIT3, TP53I11 and FAS, whereas downregulated the expression of MDM4 and SIVA1, thus promoting apoptosis. HBO upregulated the expression of CDC25A, MCM2, PCNA, RFC33, DSCC1 and CDC14A, whereas downregulated the expression of ASNS, CDK6, CDKN1B, PTBP3 and MAD2L1, thus inhibiting cell cycle progression. Among these DEGs, 17 indicator-genes of HBO prolonging survival were detected. Conclusions: HBO is beneficial for glioblastoma. Glioblastoma patients with these predictive indicators may prolong survival with HBO therapy. These potential therapeutic targets especially COL1A1, ADAMTS1 and PTBP3 deserve further validation.

In the simultaneous localization and mapping (SLAM) technique, the presence of cumulative errors in laser odometry positions leads to localization bias or even map-building failure. To address this problem, a laser SLAM method called PA-SLAM based on ground plane constraints and two-step accurate identification of loopback frames is proposed. In the point cloud preprocessing process, the Patchwork++ method is introduced to obtain the ground plane constraints to reduce the localization error caused by invalid feature point matching. Then, accurate six-degree-of-freedom bit positions of the carrier are obtained from Lidar orientation and map construction (LOAM), candidate loopback frames are obtained by searching within a certain radius according to the k-dimensional (K-D) tree data structure, and a Lidar Iris descriptor is introduced to calculate the similarity scores among the candidate frames. Finally, the fast generalized iterative closest point (FasterGICP) algorithm is introduced to obtain the loopback position constraints to correct the global pose, so as to obtain more accurate localization information. The proposed method is compared with the LeGO-LOAM and SC-LeGO-LOAM algorithms on the KITTI dataset. The experimental results show that the absolute position root-mean-square error (RMSE) of this method is reduced by 45.7$\%$ and 48.3$\%$ on average relative to the above two algorithms, which plays a significant role in eliminating the cumulative error of the position, and realizes a more robust and accurate localization and 3-D map construction.

Designing phase transition (PT) materials and manipulating their properties are significant but challenging tasks. In this study, we explore a strategy to design molecule-based spin-Peierls-type PT materials and manipulate their PT features by modifying intermolecular van der Waals interactions within the crystal. We successfully synthesized three isomorphic one-dimensional spin-Peierls-type PT salts [Me3NCH2X][Ni(mnt)2], where mnt2–is maleonitriledithiolate ligand and Me3NCH2X+represents halogen-substituted tetramethylammonium, with X = Cl (1), Br (2), and I (3). These salts were characterized in terms of their composition, thermal stability, and magnetic properties. Notably, the minor differences in the compositions of 1–3result in significant distinctions in their PT properties. This “butterfly effect” of halogen substitution on PT features is further discussed using Hirshfeld surface analysis. Our results reveal that ubiquitous dispersion interactions in molecular crystals can be used as an efficient tool for manipulating the PT behaviors of molecule-based functional materials.

Covalent organic framework (COF) film with electrofluorochromic (EFC) and electrochromic (EC) properties has been synthesized by using triphenylamine-based monomers. The film exhibited a high maximum fluorescence contrast of 151 when subjected to a drive voltage of 0.75 V vs the Ag/AgCl electrode, causing the fluorescence to be quenched, which resulted in the EFC process’s “fluorescence off” state. The switching times for the fluorescence on and off states were 0.51 and 7.79 s, respectively. Over the same voltage range, the COF film also displayed EC properties, achieving a contrast of 50.23% and a coloration efficiency of 297.4 cm2C–1at 532 nm, with switching times of 18.6 s for coloration and 0.7 s for bleaching. Notably, the quenched fluorescence of the COF film could be restored by adding dopamine as a reductant. This phenomenon enabled the implementation of a NAND logic gate using the applied potential as a physical input and dopamine addition as a chemical input. This study demonstrates the successful development of COF films with bifunctional EFC and EC properties, showcasing their potential for use in constructing advanced optoelectronic devices.

Ammonium dinitramide (ADN), as a novel and environmentally friendly oxidizer, has strong hygroscopicity when exposed to high-humidity air, which seriously hinders its application in solid propellants. Modification of oxidizers by cocrystallization is an effective strategy to improve the hygroscopicity of energetic components. In this paper, the theoretical simulation of ADN/CL-20 cocrystals was developed via a directional hydrogen bonding design to establish a cocrystal with improved hygroscopicity. Intermolecular interaction analyses reveal that hydrogen bonds and van der Waals interactions synergistically lead to the formation of cocrystals. The ADN/CL-20 cocrystal was prepared experimentally by the spray drying self-assembly technique, and the corresponding thermal analysis and sensitivity properties were conducted to illustrate the thermal stability and high safety. Furthermore, the critical relative humidity (CRH) measurement was carried out to evaluate the hygroscopicity of the cocrystal, exhibiting a certain degree of antihygroscopic effect with a CRH of 65%. The hydrogen bonds formed between ADN and CL-20 saturate the ammonium ions of ADN, further preventing ADN from absorbing water molecules in the air. The ADN/CL-20 cocrystal has high specific impulse characteristics (Isp: 272.6 s). Accordingly, this work clearly demonstrates that the ADN/CL-20 cocrystal is expected to be used in a solid propellant to make up for the deficiency of the ADN oxidizer.

Rearrangement reactions, one of the most important transformations in organic chemistry, represent an important yet difficult aspect of the discipline. However, rearrangement reactions that involve regioselectivity are rarely covered in traditional experimental textbooks. Herein, a novel organic chemistry laboratory experiment centered around a Schmidt-type rearrangement was designed and presented, aimed at elucidating the mechanism of this reaction and its regioselective nature for students. Before conducting the experiment, students are tasked with previewing the mechanism underlying the formation of the observed amide product from the reaction between 4-nitrobenzophenone and n-PrNO2. Given the asymmetric nature of the ketone, the potential for obtaining different amide products depends on the priority of the migration of the two aryls of 4-nitrobenzophenone during rearrangement. Through this experiment, students can discover that the product arises from the migration of the more electron-rich aryl, thereby indicating a nucleophilic rearrangement with evident regioselectivity. Additionally, the concept of green chemistry was integrated into the organic chemistry curriculum, underscoring the contribution of this improved Schmidt-type reaction in reducing toxicity and enhancing safety. This approach prompts students to recognize the imperative of green chemistry in advancing sustainable societal development, emphasizing the collective responsibility of chemists to shoulder environmentally conscious practices.

The deformation and breakup of metallic droplets during gas atomization were simulated using a volume of fluid (VOF) approach that considered droplet cooling and solidification. The correlation between the typical powder morphology and droplet breakup behavior was established to guide the preparation of spherical powder particles. The results showed that upon increasing the ratio of aerodynamic to viscous force of the droplet, the formation of spherical particles was enhanced, while upon decreasing this ratio, the expected droplet breakup mode changed or only droplet deformation occurred. Several typical scenarios were observed from the numerical simulations of the hollow particle formation and evolution process, e.g., open hollow film formation, film closure, bubble centrifugation, and bubble detachment. By increasing the gas velocity or droplet temperature, a higher non-equilibrium Laplace pressure or lower viscous forces was achieved, which separated the bubbles from the interior of the droplet.

In order to study the response law of vortex-induced vibration (VIV) of marine risers under the combined action of roughness and interference effects, and to reveal the coupling mechanism of roughness and interference effects on the riser, a VIV experiment of rough risers in tandem arrangement was conducted in a wave–current combined flume. The experiment characterized the risers’ roughness by arranging different specifications of attachments on the surface of the risers. Three rough risers with different roughness and smooth risers were arranged in tandem arrangement, with the rough risers arranged downstream. The experimental results indicate that the suppression of the attachments on the downstream risers’ vibration are more significant both in the CF and IL directions as the reduced velocity increases. For the downstream riser, the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced velocity. For the upstream risers, changes in the roughness and spacing ratio have an impact on their ‘lock-in’ region. When the roughness of downstream risers is relatively large (0.1300) and the spacing between risers is small (S/D=4.0), the reduced velocity range of ‘lock-in’ region in the CF direction of upstream risers is obviously expanded, and the displacement in the ‘lock-in’ region is severer.

DNA fragments in urine are a promising biomarker for non-invasive genetic analysis. In this study, a method was developed to capture DNA from urine by using a nylon membrane combined filter device. The nylon membranes were functionalized by chitosan which has high binding capacity for nucleic acids. The current method could capture DNA from 8 ml of standard solution with a DNA concentration as low as 0.05 ng/ml. Urine DNA was captured by this method from ten healthy people, and then, a nylon membrane with a diameter of 1.2 mm punched by a hole puncher was added in PCR to detect the leptingene. The results showed that there were normal amplification curves after PCR, indicating that the method was feasible for detecting genes in urine. The method developed in this study is non-invasive, rapid, and simple for gene detection.

An enantioselective Pd-catalyzed intramolecular dearomative reductive Heck reaction of N-(o-bromoaryl) indole-3-carboxamide is developed. By employing Pd(dba)2/SPINOL-based phosphoramidite as the chiral catalyst and HCO2Na as the hydride source, a series of enantioenriched spiro indolines bearing vicinal stereocenters were afforded in moderate to good yields with excellent enantioselectivities. The reductive Heck reaction of formal tetrasubstituted alkene bearing β-hydrogens is therefore realized by inhibiting β-H elimination.

High-precision microfabrication of functional ceramics with complex shapes and tailored properties currently arouse significant attention, but maintaining dimensional accuracy is still a research challenge. Herein, an innovative digital light processing (DLP) 3D technology is employed to fabricate calcined kaolin (Al2O3·2SiO2) ceramic with intricate structures, achieving high precision and densification. To illustrate the potential of different solid content slurries (43, 45, 46.2, and 47.5 vol%), and the curing thickness with tuned exposure time (8s, 10s, and 12s), we investigated their impact on physical properties and microstructures. The results show that the optimal sintering at 1200 °C achieved an exceptionally high density 2.38 g/cm3, with low shrinkage (17.35 %) along XY-direction and porosity reaching up to 15.53%. The highest level of solids slurry at 47.5 vol% increased the densification and open porosity. For all solid contents, the shrinkage along the Z-direction was exceeded compared to the XY-direction. A comprehensive evaluation of sintered morphologies, including their topography and chemical composition. The EDX mapping showed that kaolin ceramics have excellent stability at high temperatures. The highest flexural strength of DLP printed specimen at temperature (1200 °C) is 71.60 MPa, whereas that of the diamond porous structure is 6.66 MPa. Our work sheds light on high-precision microfabrication of complex shapes with unparalleled accuracy and efficiency, paving the way for high-performance functional ceramic materials.

Heterostructure engineering and oxygen vacancy engineering are the most promising modification strategies to reinforce the Zn2+ion storage of vanadium oxides. Herein, a rare mixed-dimensional material (VOx), composed of V2O5(2D), V3O7(3D), and V6O13(3D) heterostructures, rich in oxygen vacancies, was synthesized via thermal decomposition of layered ammonium vanadate. The VOxcathode provides an exceptional discharge capacity (411 mA h g–1at 0.1 A g–1) and superior cycling stability (the capacity retention remains close to 100% after 800 cycles at 2 A g–1) for aqueous zinc-ion batteries (AZIBs). Ex situ characterizations confirm that the byproduct Zn3V2O7(OH)2·nH2O is generated/decomposed during discharge/charge processes. Furthermore, VOxdemonstrates reversible intercalation/deintercalation of H+/Zn2+ions, enabling efficient energy storage. Remarkably, a reversible crystal-to-amorphous transformation in the V2O5phase of VOxduring charge–discharge was observed. This investigation reveals that mixed-dimensional heterostructured vanadium oxide, with abundant oxygen vacancies, serves as a highly promising electrode material for AZIBs, further advancing the comprehension of the storage mechanism within vanadium-based cathode materials.

Ion-plastic crystals (IPCs) belong to a category of solid-state electrolytes. The plastic crystal transition temperature (TC) and melting point (Tm) are their two crucial parameters as they greatly influence practical usability. Ideally, an IPC should have a low TCvalue and a high Tm. However, a paradox arises where decreasing TCleads to a decrease in Tmand vice versa. This study achieved IPC [DMPip][Ni(mnt)2] (1; DMPip+= N, N-dimethylpiperidinium, mnt2–= maleonitriledithiolate). In the crystal structure, the planar electron-delocalized anions form columns via π-orbital interactions and antiferromagnetic (AFM) couplings. The globular shape cations occupy the interstitial spaces of anion columns. This unique arrangement enhances the lattice’s thermal stability, facilitates cation migration, reduces TC, and increases Tm. Thus, 1exhibits TCnear room temperature, ΔT= Tm– TCof over 120 K, and reversible redox activity in the plastic crystal state. 1represents a novel type of plastic crystal electrolyte with inherent redox activity. These findings hold great potential for driving innovation in the development of all-solid-state redox-enhanced electrochemical devices.