Surface modification of dental zirconia implants with a low infiltration temperature glass.

The glass infiltration technique was employed for surface modification of zirconia implants in this study. The prepared glass-infiltrated zirconia with low infiltrating temperature showed excellent mechanical properties and enough infiltrating layer. The zirconia substrate was pre-sintered at 1,200°C and the glass infiltration depth reached 400 µm after infiltrating at 1,200°C for 10 h. The infiltrating glass has good wetting ability, thermal expansion match and good chemical compatibility with the zirconia substrate. Indentation fracture toughness and flexural strength of the dense sintered glass-infiltrated zirconia composite are respectively 5.37±0.45 MPa•m1/2 and 841.03±89.31 MPa. Its elasticity modulus is 163.99±7.6 GPa and has about 500 µm infiltrating layer. The glass-infiltrated zirconia can be acid etched to a medium roughness (1.29±0.09 µm) with a flexural strength of 823.65±87.46 MPa, which promotes cell proliferation and has potential for dental implants.

Cockayne Syndrome Linked to Elevated R-Loops Induced by Stalled RNA Polymerase II during Transcription Elongation.

Mutations in the Cockayne Syndrome group B (CSB) gene cause cancer in mice, but premature aging and severe neurodevelopmental defects in humans. CSB, a member of the SWI/SNF family of chromatin remodelers, plays diverse roles in regulating gene expression and transcription-coupled nucleotide excision repair (TC-NER); however, these functions do not explain the distinct phenotypic differences observed between CSB-deficient mice and humans. During investigating Cockayne Syndrome-associated genome instability, we uncover an intrinsic mechanism that involves elongating RNA polymerase II (RNAPII) undergoing transient pauses at internal T-runs where CSB is required to propel RNAPII forward. Consequently, CSB deficiency retards RNAPII elongation in these regions, and when coupled with G-rich sequences upstream, exacerbates genome instability by promoting R-loop formation. These R-loop prone motifs are notably abundant in relatively long genes related to neuronal functions in the human genome, but less prevalent in the mouse genome. These findings provide mechanistic insights into differential impacts of CSB deficiency on mice versus humans and suggest that the manifestation of the Cockayne Syndrome phenotype in humans results from the progressive evolution of mammalian genomes.

Large-scale photonic network with squeezed vacuum states for molecular vibronic spectroscopy.

Although molecular vibronic spectra generation is pivotal for chemical analysis, tackling such exponentially complex tasks on classical computers remains inefficient. Quantum simulation, though theoretically promising, faces technological challenges in experimentally extracting vibronic spectra for molecules with multiple modes. Here, we propose a nontrivial algorithm to generate the vibronic spectra using states with zero displacements (squeezed vacuum states) coupled to a linear optical network, offering ease of experimental implementation. We also fabricate an integrated quantum photonic microprocessor chip as a versatile simulation platform containing 16 modes of single-mode squeezed vacuum states and a fully programmable interferometer network. Molecular vibronic spectra of formic acid and thymine under the Condon approximation are simulated using the quantum microprocessor chip with high reconstructed fidelity ( > 92%). Furthermore, vibronic spectra of naphthalene, phenanthrene, and benzene under the non-Condon approximation are also experimentally simulated. Such demonstrations could pave the way for solving complicated quantum chemistry problems involving vibronic spectra and computational tasks beyond the reach of classical computers.

PV and SST neurons in the anterior cingulate cortex regulate social disorders in adulthood induced by sensory abnormalities in childhood.

OBJECTIVE: Childhood sensory abnormalities experience has a crucial influence on the structure and function of the adult brain. The underlying mechanism of neurological function induced by childhood sensory abnormalities experience is still unclear. Our study was to investigate whether the GABAergic neurons in the anterior cingulate cortex (ACC) regulate social disorders caused by childhood sensory abnormalities experience. METHODS: We used two mouse models, complete Freund's adjuvant (CFA) injection mice and bilateral whisker trimming (BWT) mice in childhood. We applied immunofluorescence, chemogenetic and optogenetic to study the mechanism of parvalbumin (PV) neurons and somatostatin (SST) neurons in ACC in regulating social disorders induced by sensory abnormalities in childhood. RESULTS: Inflammatory pain in childhood leads to social preference disorders, while BWT in childhood leads to social novelty disorders in adult mice. Inflammatory pain and BWT in childhood caused an increase in the number of PV and SST neurons, respectively, in adult mice ACC. Inhibiting PV neurons in ACC improved social preference disorders in adult mice that experienced inflammatory pain during childhood. Inhibiting SST neurons in ACC improved social novelty disorders in adult mice that experienced BWT in childhood. CONCLUSIONS: Our study reveals that PV and SST neurons of the ACC may play a critical role in regulating social disorders induced by sensory abnormalities in childhood.

A novel strategy to prepare high performance multifunctional composite films by combining electrostatic assembly, crosslinking, topology enhancement and sintering.

Currently, polymer-fiber composite films face the challenge of striking a balance between good mechanical properties and multi-functionalities. Here, aramid fibers (ANFs), chitosan (CS) dendritic particles, and silver nanowires (AgNWs) were used to create high-performance multifunctional composite films. AgNWs and polymer dendritic particles form an interpenetrating segregated network that ensures both a continuous conductive filler and a polymer network. Electrostatic assembly eliminates repulsion between negatively charged ANFs, cross-linked CS particles generate a stable three-dimensional network, and a "brick-mortar" structure composed of multiple materials contributes to topological enhancement. Sintering encourages local overlap and fusing of the AgNWs while reducing their internal flaws. Based on the above strategy, these films achieve a strength of 306.5 MPa, a toughness of 26.5 MJ m-3, and a conductivity of 392 S cm-1. Density functional theory (DFT) and Comsol simulations demonstrate that the introduction of CS thin layers leads to strong hydrogen bonds and three-dimensional continuous conductive networks. With its outstanding mechanical and electrical properties, the AgNW@ANF/CS-CH film demonstrates excellent electromagnetic shielding (22 879.1 dB cm2 g-1) and Joule heating (70 °C within 10 s) capabilities. This work presents a novel approach to fabricate high-performance conductive films and expand their potential applications in lightweight wearable electronics and electrothermal therapy.

Prevalence and trends of Chlamydia trachomatis infection in female sex workers and men who have sex with men in China: a systematic review and meta-analysis.

INTRODUCTION: Chlamydia trachomatis infection can cause a significant disease burden in high-risk populations. This study aimed to assess the overall prevalence of C. trachomatis infection, and determine the long-term trends and geographic distribution of this infection among female sex workers (FSWs) and men who have sex with men (MSM) in China. METHODS: The PubMed, Web of Science, CNKI, Wanfang Data and VIP databases were searched from 1 January 1990 through 30 April 2023. Publications in which C. trachomatis infection was detected using nucleic acid amplification tests (NAATs) were included. The Q test and I2 statistics were used to assess the heterogeneity between studies. A random-effect model was used to estimate the pooled prevalence of C. trachomatis infection. Subgroup, meta-regression, and sensitivity analyses were performed to explore the sources of heterogeneity. Publication bias was evaluated using Egger's test. Trend analysis of the prevalence was performed using the Jonckheere-Terpstra trend test method. RESULTS: Sixty-one studies were eligible for inclusion (including 38 for FSWs and 23 for MSM). The pooled prevalence of C. trachomatis infection was 19.5% (95% CI: 16.4, 23.0) among FSWs and 12.7% (95% CI: 9.2, 17.7) in the rectum, 6.4% (95% CI: 5.3, 7.8) in the urethra and 1.3% (95% CI: 0.8, 2.1) in the oropharynx from MSM in China. The subgroup analyses showed that the sample size, study period, study region, specimen collection type, molecular diagnosis method, and recruitment site could explain some heterogeneity among studies of FSWs, and the publication language, study period, study region, molecular diagnosis method, and specimen collection anatomical site could explain some heterogeneity among studies of MSM. From 1998 to 2004, 2005 to 2009, 2010 to 2015, and 2016 to 2021, the pooled prevalence of C. trachomatis infection among FSWs were 30.3%, 19.9%, 21.4%, and 11.3%, respectively. For MSM, the pooled prevalence from 2003 to 2009, 2010 to 2015, and 2016 to 2022 were 7.8%, 4.7%, and 6.5%, respectively. However, no overall decline in the prevalence of C. trachomatis infection was observed among FSWs (z = -1.51, P = 0.13) or MSM (z = -0.71, P = 0.48) in China. CONCLUSIONS: The prevalence of C. trachomatis infection was high in these two high-risk populations in China. The findings of this study provide evidence for the formulation of effective surveillance and screening strategies for the prevention and control of C. trachomatis infection among these two specific populations.

Identification of a third myosin-5a-melanophilin interaction that mediates the association of myosin-5a with melanosomes.

Transport and localization of melanosome at the periphery region of melanocyte are depended on myosin-5a (Myo5a), which associates with melanosome by interacting with its adaptor protein melanophilin (Mlph). Mlph contains four functional regions, including Rab27a-binding domain, Myo5a GTD-binding motif (GTBM), Myo5a exon F-binding domain (EFBD), and actin-binding domain (ABD). The association of Myo5a with Mlph is known to be mediated by two specific interactions: the interaction between the exon-F-encoded region of Myo5a and Mlph-EFBD and that between Myo5a-GTD and Mlph-GTBM. Here, we identify a third interaction between Myo5a and Mlph, that is, the interaction between the exon-G-encoded region of Myo5a and Mlph-ABD. The exon-G/ABD interaction is independent from the exon-F/EFBD interaction and is required for the association of Myo5a with melanosome. Moreover, we demonstrate that Mlph-ABD interacts with either the exon-G or actin filament, but cannot interact with both of them simultaneously. Based on above findings, we propose a new model for the Mlph-mediated Myo5a transportation of melanosomes.

Structural engineering of Pt-on-Rh hollow nanorods with high-performance peroxidase-like specific activity for colorimetric detection.

The preparation of nanozymes with high specific activity is highly important for various applications. However, only a few nanozymes have specific activities comparable to natural enzymes. Herein, novel Pt-on-Rh hollow nanorods (PtRh HNRs) were developed, in which surface Pt exhibited adjustable dispersity and interior Rh served as the support. The optimized PtRh HNRs demonstrated high-performance peroxidase (POD)-like activity, with a specific activity as high as 1352 U mg-1, which was 3.86 times that of their monometallic Pt counterparts. Density functional theory (DFT) calculations illustrated that the presence of Rh decreased the energy barrier of the rate-determining step. When PtRh HNRs were used as nanozymes in the colorimetric detection of hydrogen peroxide (H2O2) and ascorbic acid (AA), the limits of detection (LODs) were as low as 9.97 µM and 0.039 µM, respectively. The current work highlights a facile and powerful strategy for manufacturing nanozymes with high specific activity and demonstrates that the prepared PtRh HNRs have the potential for analysis and determination.

The effectiveness of digital twins in promoting precision health across the entire population: a systematic review.

Digital twins represent a promising technology within the domain of precision healthcare, offering significant prospects for individualized medical interventions. Existing systematic reviews, however, mainly focus on the technological dimensions of digital twins, with a limited exploration of their impact on health-related outcomes. Therefore, this systematic review aims to explore the efficacy of digital twins in improving precision healthcare at the population level. The literature search for this study encompassed PubMed, Embase, Web of Science, Cochrane Library, CINAHL, SinoMed, CNKI, and Wanfang Database to retrieve potentially relevant records. Patient health-related outcomes were synthesized employing quantitative content analysis, whereas the Joanna Briggs Institute (JBI) scales were used to evaluate the quality and potential bias inherent in each selected study. Following established inclusion and exclusion criteria, 12 studies were screened from an initial 1321 records for further analysis. These studies included patients with various conditions, including cancers, type 2 diabetes, multiple sclerosis, heart failure, qi deficiency, post-hepatectomy liver failure, and dental issues. The review coded three types of interventions: personalized health management, precision individual therapy effects, and predicting individual risk, leading to a total of 45 outcomes being measured. The collective effectiveness of these outcomes at the population level was calculated at 80% (36 out of 45). No studies exhibited unacceptable differences in quality. Overall, employing digital twins in precision health demonstrates practical advantages, warranting its expanded use to facilitate the transition from the development phase to broad application.PROSPERO registry: CRD42024507256.

Semisynthesis and antitumor activity of endertiin B and related triterpenoids from Ganoderma lucidum.

Ganoderma lucidum, a fungus used in traditional Chinese medicine, is known for its medicinal value attributed to its active components called Ganoderma triterpenoids (GTs). However, the limited isolation rate of these GTs has hindered their potential as promising drug candidates. Therefore, it is imperative to achieve large-scale preparation of GTs. In this study, four GTs were effectively synthesised from lanosterol. The antitumor activity of these GTs was evaluated in vivo. Endertiin B exhibited potent inhibitory activity against breast cancer cells (9.85 ± 0.91 µM and 12.12 ± 0.95 µM). Further investigations demonstrated that endertiin B significantly upregulated p21 and p27 and downregulated cyclinD1 expression, arresting the cell cycle at the G0/G1 phase and inducing apoptosis by decreasing BCL-2 and increasing BAX and BAK levels. Additionally, endertiin B was found to reduce the expression of proteins associated with the PI3K-AKT signaling pathway. To summarize, endertiin B effectively inhibited cell proliferation by blocking the cell cycle and inducing apoptosis through the PI3K-AKT pathway.

A Prospective Self-controlled Clinical Trial of Nonactivated Low Leukocyte PRP in Female Pattern Hair Loss Patients of Childbearing Age.

BACKGROUND: Alopecia significantly affects the mental health and social relationship of women since childbearing age, highlighting the need for a safe, effective, and convenient treatment. METHODS: The authors have conducted a prospective self-controlled trial involving 15 female patients at childbearing age with alopecia. These patients received a subcutaneous scalp injection of platelet-rich plasma once every 4 weeks for 3 treatments in total. Outcome measurements were included below: changes in hair density (hair/cm2), hair follicle density (hair follicle/cm2), and overall photographic assessment (improved or not) at 4, 12, and 24 weeks right after the first treatment. RESULTS: Comparing the photographs taken before and after the intervention, 67% of patients' hair density increased from 151 ± 39.82 hairs/cm2 (preintervention) to 170.96 ± 37.14 hairs/cm2 (at 24-week follow-up), representing an approximate increase of 19 hairs/cm2. Meanwhile, hair follicle density increased by approximately 15 follicles/cm2 after 24 weeks since the first treatment, rising from 151.04 ± 41.99 follicles/cm2 to 166.72 ± 37.13 follicles/cm2. The primary adverse reactions observed were local swelling and pain due to injections. CONCLUSION: Local injection of nonactivated platelet-rich plasma with low leukocytes concentration could be an effective strategy to alleviate alopecia symptoms in female patients.

P3N-PIPO but not P3 is the avirulence determinant in melon carrying the Wmr resistance against watermelon mosaic virus, although they contain a common genetic determinant.

Viruses employ a series of diverse translational strategies to expand their coding capacity, which produces viral proteins with common domains and entangles virus-host interactions. P3N-PIPO, which is a transcriptional slippage product from the P3 cistron, is a potyviral protein dedicated to intercellular movement. Here, we show that P3N-PIPO from watermelon mosaic virus (WMV) triggers cell death when transiently expressed in Cucumis melo accession PI 414723 carrying the Wmr resistance gene. Surprisingly, expression of the P3N domain, shared by both P3N-PIPO and P3, can alone induce cell death, whereas expression of P3 fails to activate cell death in PI 414723. Confocal microscopy analysis revealed that P3N-PIPO targets plasmodesmata (PD) and P3N associates with PD, while P3 localizes in endoplasmic reticulum in melon cells. We also found that mutations in residues L35, L38, P41, and I43 of the P3N domain individually disrupt the cell death induced by P3N-PIPO, but do not affect the PD localization of P3N-PIPO. Furthermore, WMV mutants with L35A or I43A can systemically infect PI 414723 plants. These key residues guide us to discover some WMV isolates potentially breaking the Wmr resistance. Through searching the NCBI database, we discovered some WMV isolates with variations in these key sites, and one naturally occurring I43V variation enables WMV to systemically infect PI 414723 plants. Taken together, these results demonstrate that P3N-PIPO, but not P3, is the avirulence determinant recognized by Wmr, although the shared N terminal P3N domain can alone trigger cell death.IMPORTANCEThis work reveals a novel viral avirulence (Avr) gene recognized by a resistance (R) gene. This novel viral Avr gene is special because it is a transcriptional slippage product from another virus gene, which means that their encoding proteins share the common N-terminal domain but have distinct C-terminal domains. Amazingly, we found that it is the common N-terminal domain that determines the Avr-R recognition, but only one of the viral proteins can be recognized by the R protein to induce cell death. Next, we found that these two viral proteins target different subcellular compartments. In addition, we discovered some virus isolates with variations in the common N-terminal domain and one naturally occurring variation that enables the virus to overcome the resistance. These results show how viral proteins with common domains interact with a host resistance protein and provide new evidence for the arms race between plants and viruses.

Superhydrophobic/ superoleophilic polystyrene-based porous material with superelasticity for highly efficient and continuous oil/water separation in harsh environments.

Three-dimensional separation materials with robust physical/chemical stability have great demand for effective and continuous separation of immiscible oil/water mixtures and water-in-oil emulsions, resulting from chemical leakages and discharge of industrial oily wastewaters. Herein, a superelastic polystyrene-based porous material with superhydrophobicity/superoleophilicity was designed and prepared by high internal phase emulsion polymerization to meet the aforementioned requirements. A flexible and hydrophobic aminopropyl terminated polydimethylsiloxane (NH2-PDMS-NH2) segment was introduced into the rigid styrene-divinylbenzene copolymer through 1, 4-conjugate addition reaction with trimethylolpropane triacrylate. The addition of NH2-PDMS-NH2 simultaneously improved the mechanical and hydrophobic properties of the porous material (the water contact angle from 141.2° to 152.2°). The material exhibited outstanding reversible compressibility (80% strain, even in liquid N2 environments) and superhydrophobic stability, even after being repeatedly compressed 100 times, water contact angle still remained above 150°. Meanwhile, the as-prepared material had outstanding hydrophobic stability in corrosive solutions (strong acidic, alkaline, high-salty, and even strong polar solvent), presence of mechanical interference, strong UV radiations, and high/low temperature environments. More importantly, the material could continuously and efficiently separate immiscible oil/water mixture and water-in-oil emulsions under the above conditions, showing huge potential for the large-scale remediation of complex oily wastewaters.

Case report: Decreased hemoglobin and multiple organ failure caused by ceftizoxime-induced immune hemolytic anemia in a Chinese patient with malignant rectal cancer.

Background: Drug-induced immune hemolytic anemia (DIIHA) is a rare but serious condition, with an estimated incidence of one in 100,000 cases, associated with various antibiotics. This study reports on a case of ceftizoxime-induced hemolysis observed in a patient in China. Case description: A Chinese patient diagnosed with malignant rectal cancer underwent antimicrobial therapy after laparoscopic partial recto-sigmoid resection (L-Dixon). After receiving four doses of ceftizoxime, the patient developed symptoms including rash, itchy skin, and chest distress, followed by a rapid decline in hemoglobin levels, the presence of hemoglobin in the urine (hemoglobinuria), renal failure, and disseminated intravascular coagulation. Laboratory analysis revealed high-titer antibodies against ceftizoxime and red blood cells (RBCs) in the patient's serum, including immunoglobulin M (IgM) (1:128) antibodies and immunoglobulin G (IgG) (1:8) antibodies, with noted crossreactivity to ceftriaxone. Significant improvement in the patient's hemolytic symptoms was observed following immediate discontinuation of the drug, two plasma exchanges, and extensive RBC transfusion. Conclusion: This case, together with previous reports, underscores the importance of considering DIIHA in patients who exhibit unexplained decreases in hemoglobin levels following antibiotic therapy. A thorough examination of the patient's medical history can provide crucial insights for diagnosing DIIHA. The effective management of DIIHA includes immediate cessation of the implicated drug, plasma exchange, and transfusion support based on the identification of specific drug-dependent antibodies through serological testing.

Agrin-Lrp4 pathway in hippocampal astrocytes restrains development of temporal lobe epilepsy through adenosine signaling.

BACKGROUND: Human patients often experience an episode of serious seizure activity, such as status epilepticus (SE), prior to the onset of temporal lobe epilepsy (TLE), suggesting that SE can trigger the development of epilepsy. Yet, the underlying mechanisms are not fully understood. The low-density lipoprotein receptor related protein (Lrp4), a receptor for proteoglycan-agrin, has been indicated to modulate seizure susceptibility. However, whether agrin-Lrp4 pathway also plays a role in the development of SE-induced TLE is not clear. METHODS: Lrp4f/f mice were crossed with hGFAP-Cre and Nex-Cre mice to generate brain conditional Lrp4 knockout mice (hGFAP-Lrp4-/-) and pyramidal neuron specific knockout mice (Nex-Lrp4-/-). Lrp4 was specifically knocked down in hippocampal astrocytes by injecting AAV virus carrying hGFAP-Cre into the hippocampus. The effects of agrin-Lrp4 pathway on the development of SE-induced TLE were evaluated on the chronic seizure model generated by injecting kainic acid (KA) into the amygdala. The spontaneous recurrent seizures (SRS) in mice were video monitored. RESULTS: We found that Lrp4 deletion from the brain but not from the pyramidal neurons elevated the seizure threshold and reduced SRS numbers, with no change in the stage or duration of SRS. More importantly, knockdown of Lrp4 in the hippocampal astrocytes after SE induction decreased SRS numbers. In accord, direct injection of agrin into the lateral ventricle of control mice but not mice with Lrp4 deletion in hippocampal astrocytes also increased the SRS numbers. These results indicate a promoting effect of agrin-Lrp4 signaling in hippocampal astrocytes on the development of SE-induced TLE. Last, we observed that knockdown of Lrp4 in hippocampal astrocytes increased the extracellular adenosine levels in the hippocampus 2 weeks after SE induction. Blockade of adenosine A1 receptor in the hippocampus by DPCPX after SE induction diminished the effects of Lrp4 on the development of SE-induced TLE. CONCLUSION: These results demonstrate a promoting role of agrin-Lrp4 signaling in hippocampal astrocytes in the development of SE-induced development of epilepsy through elevating adenosine levels. Targeting agrin-Lrp4 signaling may serve as a potential therapeutic intervention strategy to treat TLE.

The role of EUS-guided iodine-125 seed implantation in patients with unresectable ampullary cancer after relief of obstructive jaundice.

Purpose: Few studies have focused on the management of inoperable ampullary carcinoma (AC), and patients with jaundice suffer from biliary stents replacement frequently. Iodine-125 (125I) brachytherapy has been used in the treatment of malignant tumors owing to its curative effect, minimal surgical trauma, and tolerable complications. The aim of the study was to investigate the role of 125I seed implantation in patients with unresectable ampullary carcinoma after relief of obstructive jaundice. Material and methods: A total of 44 patients with obstructive jaundice resulting from unresectable ampullary carcinoma from January 1, 2010 to October 31, 2020 were enrolled in the study. Eleven patients underwent implantation of 125I seeds under endoscopic ultrasound (EUS) after receiving biliary stent placement via endoscopic retrograde cholangiopancreatography (ERCP) (treatment group), and 33 patients received a stent alone via ERCP (control group). Cox regression model was applied in this single-center retrospective comparison study. Results: The median maximum intervention interval for biliary obstruction was 381 days (interquartile range [IQR]: 204-419 days) in the treatment group and 175 days (IQR: 126-274 days) in the control group (p < 0.05). Stent occlusion rates at 90 and 180 days in the control group were 12.9% and 51.6%, respectively. No stent occlusion occurred in the treatment group. Patients in the treatment group obtained longer survival time (median, 26 vs. 13 months; p < 0.01) and prolonged duodenal obstruction (median, 20.5 vs. 11 months; p < 0.05). No brachytherapy-related grade 3 or 4 adverse events were observed. Conclusions: Longer intervention interval for biliary obstruction and survival as well as better stent patency and prolonged time to duodenal obstruction could be achieved by implanting 125I seeds combined with biliary stent in patients with unresectable ampullary cancer.

Toward Practical Single-Molecule/Atom Switches.

Electronic switches have been considered to be one of the most important components of contemporary electronic circuits for processing and storing digital information. Fabricating functional devices with building blocks of atomic/molecular switches can greatly promote the minimization of the devices and meet the requirement of high integration. This review highlights key developments in the fabrication and application of molecular switching devices. This overview offers valuable insights into the switching mechanisms under various stimuli, emphasizing structural and energy state changes in the core molecules. Beyond the molecular switches, typical individual metal atomic switches are further introduced. A critical discussion of the main challenges for realizing and developing practical molecular/atomic switches is provided. These analyses and summaries will contribute to a comprehensive understanding of the switch mechanisms, providing guidance for the rational design of functional nanoswitch devices toward practical applications.

Regulation of π-π interactions between single aromatic molecules by bias voltage.

π-stacking interaction, as a fundamental type of intermolecular interaction, plays a crucial role in generating new functional molecules, altering the optoelectronic properties of materials, and maintaining protein structural stability. However, regulating intermolecular π-π interactions at the single-molecule level without altering the molecular conformation as well as the chemical properties remains a significant challenge. To this end, via conductance measurement with thousands of single molecular junctions employing a series of aromatic molecules, we demonstrate that the π-π coupling between neighboring aromatic molecules with rigid structures in a circuit can be greatly enhanced by increasing the bias voltage. We further reveal that this universal regulating effect of bias voltage without molecular conformational variation originates from the increases of the molecular dipole upon an applied electric field. These findings not only supply a non-destructive method to regulate the intermolecular interactions offering an approach to modulate the electron transport through a single molecular junction, but also deepen the understanding of the mechanism of π-π interactions.

A study of extractive summarization of long documents incorporating local topic and hierarchical information.

In recent years, the transformer-based language models have achieved remarkable success in the field of extractive text summarization. However, there are still some limitations in this kind of research. First, the transformer language model usually regards the text as a linear sequence, ignoring the inherent hierarchical structure information of the text. Second, for long text data, traditional extractive models often focus on global topic information, which poses challenges in how they capturing and integrating local contextual information within topic segments. To address these issues, we propose a long text extractive summarization model that employs a local topic information extraction module and a text hierarchical extraction module to capture the local topic information and document's hierarchical structure information of the original text. Our approach enhances the ability to determine whether a sentence belongs to the summary. In this experiment, ROUGE score is used as the experimental evaluation index, and evaluates the model on three large public datasets. Through experimental validation, the model demonstrates superior performance in terms of ROUGE-1, ROUGE-2, and ROUGE-L scores compared to current mainstream summarization models, affirming the effectiveness of incorporating local topic information and document hierarchical structure into the model.