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Modeling dynamic interactions among network components is crucial to uncovering the evolution mechanisms of complex networks. Recently, spatio-temporal graph learning methods have achieved noteworthy results in characterizing the dynamic changes of inter-node relations (INRs). However, challenges remain: The spatial neighborhood of an INR is underexploited, and the spatio-temporal dependencies in INRs' dynamic changes are overlooked, ignoring the influence of historical states and local information. In addition, the model's explainability has been understudied. To address these issues, we propose an explainable spatio-temporal graph evolution learning (ESTGEL) model to model the dynamic evolution of INRs. Specifically, an edge attention module is proposed to utilize the spatial neighborhood of an INR at multi-level, i.e., a hierarchy of nested subgraphs derived from decomposing the initial node-relation graph. Subsequently, a dynamic relation learning module is proposed to capture the spatio-temporal dependencies of INRs. The INRs are then used as adjacent information to improve the node representation, resulting in comprehensive delineation of dynamic evolution of the network. Finally, the approach is validated with real data on brain development study. Experimental results on dynamic brain networks analysis reveal that brain functional networks transition from dispersed to more convergent and modular structures throughout development. Significant changes are observed in the dynamic functional connectivity (dFC) associated with functions including emotional control, decision-making, and language processing.
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PURPOSE: The optimal treatment after neoadjuvant chemoimmunotherapy for patients with stage III non-small cell lung cancer (NSCLC) is unclear. This study aimed at comparing the efficacy and safety of chemoradiotherapy and surgery after neoadjuvant chemoimmunotherapy in stage III NSCLC. MATERIALS AND METHODS: We conducted a real-world multicenter retrospective study on patients with stage III NSCLC who received surgery or chemoradiotherapy after neoadjuvant chemoimmunotherapy between October 2018 and December 2022. Progression-free survival (PFS) and overall survival (OS) were assessed from the initiation of neoadjuvant treatment and estimated by the KaplanâMeier method. Univariate and multivariate Cox regression models were used to examine potential prognostic factors. One-to-one propensity score matching (PSM) was used to further minimize confounding. RESULTS: A total of 239 eligible patients were enrolled, with 104 (43.5%) receiving surgery and 135 (56.5%) receiving CRT. After 1:1 PSM, 1- and 2-year PFS rates in patients receiving radical surgery (rSurgery group) vs. patients receiving definitive cCRT (dCCRT group) were 80.0% vs. 79.2% and 67.2% vs. 53.1%, respectively (P = 0.774). One- and 2-year OS rates were 97.5% vs. 97.4% and 87.3% vs. 89.9%, respectively (P = 0.558). Patients in the dCCRT group had a numerically lower incidence of distant metastases compared to those in the rSurgery group (42.9% vs. 70.6%, P = 0.119). The incidence of treatment-related adverse events was similar in both groups, except that the incidence of grade 3/4 hematological toxicity was significantly higher in the dCCRT group (30.0% vs. 10.0%, P = 0.025). CONCLUSION: Following neoadjuvant chemoimmunotherapy, definitive concurrent chemoradiotherapy may achieve noninferior outcomes to radical surgery in stage III NSCLC.
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Carcinoma Pulmonar de Células não Pequenas , Quimiorradioterapia , Neoplasias Pulmonares , Terapia Neoadjuvante , Estadiamento de Neoplasias , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Masculino , Estudos Retrospectivos , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Terapia Neoadjuvante/métodos , Pessoa de Meia-Idade , Quimiorradioterapia/métodos , Idoso , Imunoterapia/métodos , Adulto , Prognóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
Injectable bioadhesives are attractive for managing gastric ulcers through minimally invasive procedures. However, the formidable challenge is to develop bioadhesives that exhibit high injectability, rapidly adhere to lesion tissues with fast gelation, provide reliable protection in the harsh gastric environment, and simultaneously ensure stringent standards of biocompatibility. Here, a natural bioadhesive with tunable cohesion is developed based on the facile and controllable gelation between silk fibroin and tannic acid. By incorporating a hydrogen bond disruptor (urea or guanidine hydrochloride), the inherent network within the bioadhesive is disturbed, inducing a transition to a fluidic state for smooth injection (injection force <5 N). Upon injection, the fluidic bioadhesive thoroughly wets tissues, while the rapid diffusion of the disruptor triggers instantaneous in situ gelation. This orchestrated process fosters the formed bioadhesive with durable wet tissue affinity and mechanical properties that harmonize with gastric tissues, thereby bestowing long-lasting protection for ulcer healing, as evidenced through in vitro and in vivo verification. Moreover, it can be conveniently stored (≥3 m) postdehydration. This work presents a promising strategy for designing highly injectable bioadhesives utilizing natural feedstocks, avoiding any safety risks associated with synthetic materials or nonphysiological gelation conditions, and offering the potential for minimally invasive application.
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Ligação de Hidrogênio , Úlcera Gástrica , Animais , Úlcera Gástrica/tratamento farmacológico , Injeções , Adesivos Teciduais/química , Adesivos/química , Fibroínas/química , Taninos/química , Ratos Sprague-DawleyRESUMO
Hyaluronic acid and zwitterionic hydrogels are soft materials with poor mechanical properties. The unique structures and physiological properties make them attractive candidates for ideal hydrogel dressings, but the crux of lacking satisfying mechanical strengths and adhesive properties is still pendent. In this study, the physical cross-linking of dipole-dipole interactions of zwitterionic pairs was utilized to enhance the mechanical properties of hydrogels. The hydrogels have been prepared by copolymerizing methacrylate hyaluronic (HAGMA) with carboxybetaine methacrylamide (CBMAA) (the mass ratio of [HAGMA]/[CBMAA] is 2:5, 1:5, 1:10, or 1:20), obtaining HA-CB2.5, HA-CB5.0, HA-CB10.0, or HA-CB20.0 hydrogel. Therein, the HA-CB20.0 hydrogel with a high CBMAA content can generate a strong dipole-dipole interaction to form internal physical cross-links, exhibit stretchability and low elastic modulus, and withstand 99% compressive deformation and cyclic compression under strain at 90%. Moreover, the HA-CB20.0 hydrogel is adhesive to diverse substrates, including skin, glass, stainless steel, and plastic. The synergistic effect of HAGMA and CBMAA shows strong anti-biofouling, high water absorption, biodegradability under hyaluronidase, and biocompatibility.
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Incrustação Biológica , Ácido Hialurônico , Ácido Hialurônico/química , Metacrilatos , Adesivos , Cimentos de Resina , Hidrogéis/químicaRESUMO
Ursolic acid (UA) is a naturally occurring pentacyclic triterpenoid widely found in fruits and vegetables. It has been reported that UA has anti-inflammatory effects. However, its efficacy and mechanism of action in the treatment of chronic prostatitis (CP) remain unclear. This study aimed to investigate the efficacy of UA treatment in CP and further explore the underlying mechanism. CP rat and pyroptosis cell models were established in vivo and in vitro, respectively. The efficacy of UA in inhibiting CP was evaluated via haematoxylin-eosin (HE) staining and measurement of inflammatory cytokines. RNA sequencing and molecular docking were used to predict the therapeutic targets of UA in CP. The expression of pyroptosis-related proteins was examined using various techniques, including immunohistochemistry, immunofluorescence, and flow cytometry. UA significantly ameliorated pathological damage and reduced the levels of proinflammatory cytokines in the CP model rats. RNA sequencing analysis and molecular docking suggested that NLRP3, Caspase-1, and GSDMD may be key targets. We also found that UA decreased ROS levels, alleviated oxidative stress, and inhibited p-NF-κB protein expression both in vivo and in vitro. UA improved pyroptosis morphology as indicated by electron microscope and inhibited the expression of the pyroptosis-related proteins NLRP3, Caspase-1, ASC, and GSDMD, reversed the levels of IL-1ß, IL-18, and lactate dehydrogenase in vivo and in vitro. UA can mitigate CP by regulating the NLRP3 inflammasome-mediated Caspase-1/GSDMD pathway. Therefore, UA may be a potential for the treatment of CP.
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Inflamassomos , Prostatite , Humanos , Masculino , Ratos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ácido Ursólico , Piroptose/fisiologia , Caspase 1/metabolismo , Prostatite/tratamento farmacológico , Simulação de Acoplamento Molecular , Gasderminas , Proteínas de Ligação a Fosfato/metabolismo , Proteínas de Ligação a Fosfato/farmacologiaRESUMO
Two-dimensional (2D) materials have drawn extensive attention due to their exceptional characteristics and potential uses in electronics and energy storage. This investigation employs simulations using molecular dynamics to examine the mechanical and thermal transport attributes of the 2D silicene-germanene (Si-Ge) lateral heterostructure. The pre-existing cracks of the Si-Ge lateral heterostructure are addressed with external strain. Then, the effect of vacancy defects and temperature on the mechanical attributes is also investigated. By manipulating temperature and incorporating vacancy defects and pre-fabricated cracks, the mechanical behaviors of the Si-Ge heterostructure can be significantly modulated. In order to investigate the heat transport performance of the Si-Ge lateral heterostructure, a non-equilibrium molecular dynamics approach is employed. The efficient phonon average free path is obtained as 136.09 nm and 194.34 nm, respectively, in the Si-Ge heterostructure with a zigzag and armchair interface. Our results present the design and application of thermal management devices based on the Si-Ge lateral heterostructure.
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BACKGROUND: In recent years, several studies have demonstrated that stress hyperglycemia is significantly associated with poor prognosis in patients diagnosed with acute coronary syndrome (ACS). In the present study, we aimed to investigate the potential associations between various markers of stress hyperglycemia, such as admission blood glucose (ABG), fasting blood sugar (FBS), and stress hyperglycemia ratio (SHR) with different definitions, and the occurrence of adverse cardiovascular events in patients diagnosed with ST-elevation myocardial infarction (STEMI) who have undergone percutaneous coronary intervention (PCI). METHODS: Our study enrolled a total of 1099 patients diagnosed with STEMI who underwent PCI from 2016 to 2021. The primary outcomes of this study were in-hospital death and all-cause mortality. RESULTS: Stress hyperglycemia was associated with a higher incidence of in-hospital death (ABG OR: 1.27 95% CI 1.19-1.36; FBS OR: 1.25 95% CI 1.16-1.35; SHR1 OR: 1.61 95% CI 1.21-2.14; SHR2 OR: 1.57, 95%CI 1.22-2.01; SHR3 OR: 1.59, 95%CI 1.24-2.05) and all-cause mortality (ABG HR: 1.10, 95% CI 1.07-1.14; FBS HR: 1.12, 95 CI 1.07-1.17; SHR1 HR: 1.19 95% CI 1.03-1.39; SHR2 HR: 1.28, 95%CI 1.14-1.44; SHR3 HR: 1.29, 95%CI 1.14-1.45) after adjusting for ischemic time, age, gender, BMI, hypertension, hyperlipidemia, diabetes mellitus (DM), current smoking history, chronic kidney disease (CKD), previous history of coronary artery disease (CAD), atrial fibrillation (AF), heart failure (HF), stroke, cancer, culprit vessel, multi-vessel disease. These associations exhibited a non-linear, J-shaped pattern, wherein the risk significantly increased when the ABG and FBS levels exceeded 5mmol/L. Moreover, the inflection point for SHR was estimated to be 1.2. CONCLUSIONS: Stress hyperglycemia was significantly associated with an increased risk of in-hospital death and all-cause mortality in STEMI patients treated with PCI. Stress hyperglycemia should be considered a high-risk prognostic marker in all STEMI patients, regardless of with or without diabetes.
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Diabetes Mellitus , Hiperglicemia , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Estudos de Coortes , Mortalidade Hospitalar , Intervenção Coronária Percutânea/efeitos adversos , Resultado do Tratamento , Hiperglicemia/diagnóstico , Diabetes Mellitus/diagnóstico , Glicemia , Fatores de RiscoRESUMO
This meta-analysis was conducted to systematically evaluate the prognostic role of the Naples prognostic score (NPS) in patients with gastrointestinal (GI) cancers. A comprehensive literature search of several major databases was performed for studies published until October 16, 2022. Hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted and pooled by fixed-effects or random-effects models to analyze the associations between the NPS and overall survival (OS), cancer-specific survival (CSS), and recurrence-free/disease-free survival (RFS/DFS) in GI cancers. Thirteen studies were included in the meta-analysis. Pooled results indicated that a high NPS predicted poor OS (HR = 2.28, 95% CI: 1.90-2.74, p < 0.001), CSS (HR = 2.77, 95% CI: 2.10-3.66, p < 0.001), and RFS/DFS (HR = 2.77, 95% CI: 2.26-3.40, p < 0.001). For OS-related and RFS/DFS-related studies, subgroup analyses showed that a high NPS was significantly associated with poor OS and RFS/DFS irrespective of NPS group, calculation of the NPS, and tumor type. In the study that focused on CSS, subgroup analyses by NPS group and calculation of the NPS revealed similar results. The NPS may represent an effective prognostic indicator in patients with GI cancers.
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Neoplasias Gastrointestinais , Humanos , Prognóstico , Intervalo Livre de Doença , Modelos de Riscos ProporcionaisRESUMO
Muscle regeneration is indispensable for skeletal muscle health and daily life when injury, muscular disease, and aging occur. Among the muscle regeneration, muscle stem cells' (MuSCs) activation, proliferation, and differentiation play a key role in muscle regeneration. Purines bind to its specific receptors during muscle development, which transmit environmental stimuli and play a crucial role of modulator of muscle regeneration. Evidences proved P2R expression during development and regeneration of skeletal muscle, both in human and mouse. In contrast to P2XR, which have been extensively investigated in skeletal muscles, the knowledge of P2YR in this tissue is less comprehensive. This review summarized muscle regeneration via P2Y1R and P2Y2R and speculated that P2Y1R and P2Y2R might be potential molecular triggers for MuSCs' activation and proliferation via the p-ERK1/2 and PLC pathways, explored their cascade effects on skeletal muscle, and proposed P2Y1/2 receptors as potential pharmacological targets in muscle regeneration, to advance the purinergic signaling within muscle and provide promising strategies for alleviating muscular disease.
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Músculo Esquelético , Doenças Musculares , Animais , Humanos , Camundongos , Diferenciação Celular , Músculo Esquelético/metabolismo , Doenças Musculares/metabolismo , Regeneração/fisiologia , Transdução de Sinais , Receptores Purinérgicos P2Y1/metabolismo , Receptores Purinérgicos P2Y2/metabolismoRESUMO
Very recently, two-dimensional MoSi2N4 has been synthetized (Y.-L. Hong, Z. Liu, L. Wang, T. Zhou, W. Ma, C. Xu, S. Feng, L. Chen, M.-L. Chen and D.-M. Sun, Chemical vapor deposition of layered two-dimensional MoSi2N4 materials, Science, 2020, 369, 670-674.). In this work, we systematically explore the mechanical, electronic, and catalytic properties of the MX2Y4 (M = Cr, Hf, Mo, Ti, W, Zr; X = Si, Ge; Y = N, P, As) monolayers by first-principles calculations. These observed monolayers exhibit an isotropic Young's moduli of 165-514 N m-1 and a Poisson's ratio of 0.26-0.33. The calculated band structures indicate that their bandgaps are in the range of 0.49-2.05 eV at the HSE06 level. In particular, a high electron mobility of about 1.04 × 104 cm2 V-1 s-1 is observed in TiSi2N4 monolayers, which shows potential for high-speed electronic devices. MX2Y4 monolayers also reveal decent performances in the hydrogen evolution reaction. More importantly, the Gibbs free energy change of the TiSi2N4 (ZrSi2N4) monolayer is as small as 0.078 eV (-0.035 eV), even being comparable with that of Pt (-0.09 eV). This investigation suggests that the MoSi2N4 family monolayers have potential advanced applications such as photocatalytic, electrocatalytic, and photovoltaic devices.
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In recent decades, there are immense applications for bulk and few-layer magnetic insulators in biomedicine, data storage, and signal transfer. In these applications, the interaction between spin and lattice vibration has significant impacts on the device performance. In this article, we systematically review the fundamental physical aspects of magnon-phonon coupling in magnetic insulators. We first introduce the fundamental physics of magnons and magnon-phonon coupling in magnetic insulators and then discuss the influence of magnon-phonon coupling on the properties of magnons and phonons. Finally, a summary is presented, and we also discuss the possible open problems in this field. This article presents the advanced understanding of magnon-phonon coupling in magnetic insulators, which provides new opportunities for improving various possible applications.
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Defect engineering has been considered as an effective way for controlling the heat transport properties of two-dimensional materials. In this work, the effects of point vacancies and grain boundaries on the mechanical and thermal performances of SiC and GeC monolayers are investigated systematically by molecular dynamics calculations. The failure strength in SiC and GeC is decreased by introducing vacancies at room temperature, and the stress-strain relationship can be tuned significantly by different kinds of vacancies. When the grain boundary of 21.78° is applied, the maximal fracture strengths can be as large as 27.56% for SiC and 23.56% for GeC. Also, the thermal properties of the two monolayers show a remarkable dependence on the vacancies and grain boundaries. The high vacancy density in SiC and GeC can induce disordered heat flow and the C/Ge point defect is crucial for thermal conductivity regulation for the Si/GeC monolayer. More importantly, the SiC and GeC monolayers with a grain boundary of 5.09° show excellent interfacial thermal conductance. Our findings are of great importance in understanding SiC and GeC monolayers and seeking their potential applications.
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We aim to study the inhibitory effect of alkaline serine protease (ASPNJ) on lymphocytic leukemia Jurkat cells and its related mechanism through examining the expression of membrane proteins or membrane-associated proteins. MTT assay and trypan blue staining were used to detect the inhibitory effect of ASPNJ on the proliferation and growth of Jurkat cells. Wright-Giemsa staining was used to observe the effect of ASPNJ on the morphology of Jurkat cells. The effect of ASPNJ on Jurkat cell apoptosis was detected by flow cytometry. Two-dimensional electrophoresis-mass spectrometry (2-DE-MS) was used to detect and identify the differentially expressed proteins of Jurkat cells treated with ASPNJ (4 µg/mL, 3 h), of which three were selected and verified by Western blot. ASPNJ significantly inhibited the proliferation of leukemia cells (Raji, U937, and Jurkat), caused obvious morphological changes, and induced apoptosis of Jurkat cells. ASPNJ also increased the sensitivity of Jurkat cells to vincristine (VCR). Seven differentially expressed proteins were obtained through 2DE-MS, of which Peroxiredoxin-6 (PRDX6), Calcium-binding protein (CHP1), and 40S ribosomal protein SA (RPSA) were validated. ASPNJ can cause significant toxic effects on Jurkat cells and enhance the effects of VCR. The mechanism of action of ASPNJ on Jurkat cells may be related to differentially expressed proteins such as PRDX6. This study provides a new experimental basis and direction for antileukemia research.
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Serina Proteases , Serina , Humanos , Células Jurkat , Serina Proteases/farmacologia , Proteínas de Membrana , Proliferação de Células , Vincristina/farmacologia , Apoptose , Serina EndopeptidasesRESUMO
BACKGROUND: The risk assessment of patients with stable chest pain (SCP) to defer further cardiovascular testing is crucial, but the most appropriate risk assessment strategy remains unknown. We aimed to compare current strategies to identify low risk SCP patients. METHODS: 5289 symptomatic patients who had undergone coronary artery calcium score (CACS) and coronary computed tomographic angiography scan were identified and followed. Pretest probability (PTP) of obstructive coronary artery disease (CAD) for every patient was estimated according to European Society of Cardiology (ESC)-PTP model and CACS-weighted clinical likelihood (CACS-CL) model, respectively. Based on the 2019 ESC guideline-determined risk assessment strategy (ESC strategy) and CACS-CL model-based risk assessment strategy (CACS-CL strategy), all patients were divided into low and high risk group, respectively. Area under receiver operating characteristic curve (AUC), integrated discrimination improvement (IDI) and net reclassification improvement (NRI) was used. RESULTS: CACS-CL model provided more robust estimation of PTP than ESC-PTP model did, with a larger AUC (0.838 versus 0.735, p < 0.0001), positive IDI (9%, p < 0.0001) and less discrepancy between observed and predicted probabilities. As a result, compared to ESC strategy which only applied CACS-CL model to patients with borderline ESC-PTP, CACS-CL strategy incorporating CACS with estimation of PTP to entire SCP patients indicated a positive NRI (19%, p < 0.0001) and a stronger association to major adverse cardiovascular events, with hazard ratios: 3.97 (95% confidence intervals: 2.75-5.72) versus 5.11 (95% confidence intervals: 3.40-7.69). CONCLUSION: The additional use of CACS for all SCP patients in CACS-CL strategy improved the risk assessment of SCP patients to identify individuals at low risk.
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Cálcio , Doença da Artéria Coronariana , Humanos , Angiografia Coronária/métodos , Vasos Coronários/diagnóstico por imagem , Fatores de Risco , Doença da Artéria Coronariana/diagnóstico por imagem , Medição de Risco , Dor no Peito/diagnóstico , Dor no Peito/etiologia , Angiografia por Tomografia Computadorizada/métodos , Valor Preditivo dos TestesRESUMO
Gold nanochains (AuNCs) were prepared, and this novel material was combined with carboxylated multi-walled carbon nanotubes (cMWCNTs) to be a nanocomposite for the first time. The transmission electron microscopy (TEM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and UV-Vis spectra were used to characterize the successful preparation of AuNCs and AuNC-cMWCNT composite. Based on this hybrid material, a voltammetric sensor of bisphenol A (BPA) was established. The proposed sensor displayed excellent performance for the measurement of BPA by obvious decreased anodic peak potential and enlarged peak current. Using the optimized conditions, BPA was detected using linear sweep voltammetry, and the linear range showed as wide as 0.5 µM to 2000 µM with the detection limit estimated to be 12 nM (S/N = 3). The as-proposed sensor also exhibited satisfactory performance in determining BPA of actual plastic samples.
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Nanotubos de Carbono , Nanotubos de Carbono/química , Ouro/química , Técnicas Eletroquímicas/métodos , Fenóis/química , EletrodosRESUMO
In recent years, the two-dimensional (2D) orthorhombic SiP2 flake has been peeled off successfully by micromechanical exfoliation and it exhibits an excellent performance in photodetection. In this paper, we investigated the mechanical properties and the origin of its anisotropy in an orthorhombic SiP2 monolayer through first-principles calculations, which can provide a theoretical basis for utilizing and tailoring the physical properties of a 2D orthorhombic SiP2 in the future. We found that the Young's modulus is up to 113.36 N/m along the a direction, while the smallest value is only 17.46 N/m in the b direction. The in-plane anisotropic ratio is calculated as 6.49, while a similar anisotropic ratio (~6.55) can also be observed in Poisson's ratio. Meanwhile, the in-plane anisotropic ratio for the fracture stress of the orthorhombic SiP2 monolayer is up to 9.2. These in-plane anisotropic ratios are much larger than in black phosphorus, ReS2, and biphenylene. To explain the origin of strong in-plane anisotropy, the interatomic force constants were obtained using the finite-displacement method. It was found that the maximum of interatomic force constant along the a direction is 5.79 times of that in the b direction, which should be considered as the main origin of the in-plane anisotropy in the orthorhombic SiP2 monolayer. In addition, we also found some negative Poisson's ratios in certain specific orientations, allowing the orthorhombic SiP2 monolayer to be applied in next-generation nanomechanics and nanoelectronics.
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Two-dimensional materials have been developed as novel photovoltaic and photocatalytic devices because of their excellent properties. In this work, four δ-IV-VI monolayers, GeS, GeSe, SiS and SiSe, are investigated as semiconductors with desirable bandgaps using the first-principles method. These δ-IV-VI monolayers exhibit exceptional toughness; in particular, the yield strength of the GeSe monolayer has no obvious deterioration at 30% strain. Interestingly, the GeSe monolayer also possesses ultrahigh electron mobility along the x direction of approximately 32,507 cm2·V-1·s-1, which is much higher than that of the other δ-IV-VI monolayers. Moreover, the calculated capacity for hydrogen evolution reaction of these δ-IV-VI monolayers further implies their potential for applications in photovoltaic and nano-devices.
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A biphenylene network is a novel 2D allotropy of carbon with periodic 4-6-8 rings, which was synthesized successfully in 2021. In recent years, although the mechanical properties and thermal transport received a lot of research attention, how to open the Dirac cone in the band structure of a biphenylene network is still a confused question. In this work, we utilized uniaxial and biaxial lattice strains to manipulate the electronic properties and phonon frequencies of biphenylene, and we found an indirect band gap under 10% biaxial strain through the first-principles calculations. This indirect band gap is caused by the competition between the band-edge state A and the Dirac cone for the conduction band minimum (CBM). Additionally, the lightest carrier's effective mass in biphenylene is 0.184 m0 for electrons along x (ΓâX) direction, while the effective mass for holes shows a remarkable anisotropy, suggesting the holes in the tensile biphenylene monolayer are confined within a one-dimensional chain along x direction. For phonon dispersion, we discovered that the Raman-active Ag3 phonon mode shows a robust single phonon mode character under both compressive and tensile strain, but its frequency is sensitive to lattice strain, suggesting the lattice strain in biphenylene can be identified by Raman spectroscopy.
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Neurological symptoms are prevalent in both the acute and post-acute phases of coronavirus disease 2019 (COVID-19), and they are becoming a major concern for the prognosis of COVID-19 patients. Accumulation evidence has suggested that metal ion disorders occur in the central nervous system (CNS) of COVID-19 patients. Metal ions participate in the development, metabolism, redox and neurotransmitter transmission in the CNS and are tightly regulated by metal ion channels. COVID-19 infection causes neurological metal disorders and metal ion channels abnormal switching, subsequently resulting in neuroinflammation, oxidative stress, excitotoxicity, neuronal cell death, and eventually eliciting a series of COVID-19-induced neurological symptoms. Therefore, metal homeostasis-related signaling pathways are emerging as promising therapeutic targets for mitigating COVID-19-induced neurological symptoms. This review provides a summary for the latest advances in research related to the physiological and pathophysiological functions of metal ions and metal ion channels, as well as their role in COVID-19-induced neurological symptoms. In addition, currently available modulators of metal ions and their channels are also discussed. Collectively, the current work offers a few recommendations according to published reports and in-depth reflections to ameliorate COVID-19-induced neurological symptoms. Further studies need to focus on the crosstalk and interactions between different metal ions and their channels. Simultaneous pharmacological intervention of two or more metal signaling pathway disorders may provide clinical advantages in treating COVID-19-induced neurological symptoms.
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COVID-19 , Doenças do Sistema Nervoso , Humanos , SARS-CoV-2 , Doenças do Sistema Nervoso/tratamento farmacológico , Sistema Nervoso CentralRESUMO
In this work, we explore the impacts of charge doping on the magnetism of a Cr2Ge2Te6 monolayer using first-principles calculations. Our results reveal that doping with 0.3 electrons per unit cell can enhance the ferromagnetic exchange constant in a Cr2Ge2Te6 monolayer from 6.874 meV to 10.202 meV, which is accompanied by an increase in the Curie temperature from ~85 K to ~123 K. The enhanced ratio of the Curie temperature is up to 44.96%, even higher than that caused by surface functionalization on monolayer Cr2Ge2Te6, manifesting the effectiveness of charge doping by improving the magnetic stability of 2D magnets. This remarkable enhancement in the ferromagnetic exchange constant and Curie temperature can be attributed to the increase in the magnetic moment on the Te atom, enlarged Cr-Te-Cr bond angle, reduced Cr-Te distance, and the significant increase in super-exchange coupling between Cr and Te atoms. These results demonstrate that charge doping is a promising route to improve the magnetic stability of 2D magnets, which is beneficial to overcome the obstacles in the application of 2D magnets in spintronics.