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1.
iScience ; 27(5): 109778, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38746665

RESUMEN

Depressive symptoms usually precede the cognitive decline in Alzheimer disease (AD) and worsen the clinical outcome. However, the neural circuitry mediating early emotional dysfunction, especially depressive symptoms in AD, remains elusive. Anterior cingulate cortex (ACC) is closely related to depression and vulnerable in AD. By quantitative whole-brain mapping and electrophysiological recording, we found that the decreased axonal calcium activity in neurons of ACC and the glutamatergic projection from ACC to the ventral hippocampal CA1 (vCA1) is significantly impaired in 3-month-old 5×FAD mice, which exhibit depressive-like phenotype before cognition defects in early stage. The activation of ACC-vCA1 circuit by chemogenetic manipulation efficiently ameliorated the early depressive-like behaviors in 5×FAD mice. We further identified the upregulated neuregulin-1 (Nrg1) in ACC impaired the excitatory synaptic transmission from the ACC to vCA1 in AD. Our work reveals the role of ACC-vCA1 circuit in regulating AD associated depression symptom in a mouse model of AD.

2.
Fitoterapia ; 176: 106010, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38740341

RESUMEN

Flowers of Hosta plantaginea (H. plantaginea), a widely utilized medicinal herb in Mongolian medicine, holds a significant historical background in terms of its medicinal applications. This herb is renowned for its ability to clear heat and detoxify the body, alleviate cough, and provide relief to the throat. However, the active ingredients and the potential mechanism of action remain ambiguity. The objective of this study was to conduct a comprehensive analysis of the efficacy of H. plantaginea in treating pneumonia, identify its active ingredients and unveil the pharmacological mechanism in the treatment of pneumonia. In vivo experiments demonstrate the plant's anti-pneumonia properties, while mass spectrometry analysis identifies 62 chemicals, with 14 absorbed into the bloodstream. Network pharmacology and Venn analysis reveal 195 targets of 52 active ingredients, with 49 gene targets common to H. plantaginea and pneumonia. Protein-protein interaction (PPI) network construction and enrichment analysis highlight the key targets and pathways such as AKT, EGFR, IL-17. Western blotting confirms downregulation of these pathways, indicating the anti-inflammatory effects of H. plantaginea in treating acute lung injury. Our findings showed that the treatment of ALI with the H. plantaginea exerts its anti-inflammatory effects through multiple components, targets, and pathways. This study established a solid experimental foundation for investigating the various components, targets, and pathways involved in the treatment of pneumonia using H. plantaginea. It offers valuable insights from multiple perspectives and can serve as a reference for the clinical application of this plant in pneumonia treatment.

3.
J Med Chem ; 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38727048

RESUMEN

Promising targeted therapy options to overcome drug resistance and side effects caused by platinum(II) drugs for treatment in hepatocellular carcinoma are urgently needed. Herein, six novel multifunctional platinum(IV) complexes through linking platinum(II) agents and glycyrrhetinic acid (GA) were designed and synthesized. Among them, complex 20 showed superior antitumor activity against tested cancer cells including cisplatin resistance cells than cisplatin and simultaneously displayed good liver-targeting ability. Moreover, complex 20 can significantly cause DNA damage and mitochondrial dysfunction, promote reactive oxygen species generation, activate endoplasmic reticulum stress, and eventually induce apoptosis. Additionally, complex 20 can effectively inhibit cell migration and invasion and trigger autophagy and ferroptosis in HepG-2 cells. More importantly, complex 20 demonstrated stronger tumor inhibition ability than cisplatin or the combo of cisplatin/GA with almost no systemic toxicity in HepG-2 or A549 xenograft models. Collectively, complex 20 could be developed as a potential anti-HCC agent for cancer treatment.

4.
Heliyon ; 10(9): e30488, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38737264

RESUMEN

Salvia miltiorrhiza Bunge (SM) is a widespread herbal therapy for myocardial ischemia (MI). Nevertheless, the therapeutic signaling networks of SM extract on MI is yet unknown. Emerging evidences suggested that alterations in cardiac metabolite influences host metabolism and accelerates MI progression. Herein, we employed an isoproterenol (ISO)-induced acute myocardial ischemia (AMI) rat model to confirm the pharmacological effects of SM extract (0.8, 0.9, 1.8 g/kg/day) via assessment of the histopathological alterations that occur within the heart tissue and associated cytokines; we also examined the underlying SM extract-mediated signaling networks using untargeted metabolomics. The results indicated that 25 compounds with a relative content higher than 1 % in SM aqueous extract were identified using LC-MS/MS analysis, which included salvianolic acid B, lithospermic acid, salvianolic acid A, and caffeic acid as main components. An in vivo experiment showed that pretreatment with SM extract attenuated ISO-induced myocardial injury, shown as decreased myocardial ischemic size, transformed electrocardiographic, histopathological, and serum biochemical aberrations, reduced levels of proinflammatory cytokines, inhibited oxidative stress (OS), and reversed the trepidations of the cardiac tissue metabolic profiles. Metabolomics analysis shows that the levels of 24 differential metabolites (DMs) approached the same value as controls after SM extract therapy, which were primarily involved in histidine; alanine, aspartate, and glutamate; glycerophospholipid; and glycine, serine, and threonine metabolisms through metabolic pathway analysis. Correlation analysis demonstrated that the levels of modulatory effects of SM extract on the inflammation and OS were related to alterations in endogenous metabolites. Overall, SM extract demonstrated significant cardioprotective effects in an ISO-induced AMI rat model, alleviating myocardial injury, inflammation and oxidative stress, with metabolomics analysis indicating potential therapeutic pathways for myocardial ischemia.

5.
Adv Sci (Weinh) ; : e2307953, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38582517

RESUMEN

FOXG1 syndrome is a developmental encephalopathy caused by FOXG1 (Forkhead box G1) mutations, resulting in high phenotypic variability. However, the upstream transcriptional regulation of Foxg1 expression remains unclear. This report demonstrates that both deficiency and overexpression of Men1 (protein: menin, a pathogenic gene of MEN1 syndrome known as multiple endocrine neoplasia type 1) lead to autism-like behaviors, such as social defects, increased repetitive behaviors, and cognitive impairments. Multifaceted transcriptome analyses revealed that Foxg1 signaling is predominantly altered in Men1 deficiency mice, through its regulation of the Alpha Thalassemia/Mental Retardation Syndrome X-Linked (Atrx) factor. Atrx recruits menin to bind to the transcriptional start region of Foxg1 and mediates the regulation of Foxg1 expression by H3K4me3 (Trimethylation of histone H3 lysine 4) modification. The deficits observed in menin deficient mice are rescued by the over-expression of Foxg1, leading to normalized spine growth and restoration of hippocampal synaptic plasticity. These findings suggest that menin may have a putative role in the maintenance of Foxg1 expression, highlighting menin signaling as a potential therapeutic target for Foxg1-related encephalopathy.

6.
Antioxidants (Basel) ; 13(4)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38671925

RESUMEN

Cannabis and its major cannabinoid cannabidiol (CBD) are reported to exhibit anticancer activity against skin tumors. However, the cytotoxic effects of other minor cannabinoids and synthetic CBD derivatives in melanoma are not fully elucidated. Herein, the antiproliferative activity of a panel of phytocannabinoids was screened against murine (B16F10) and human (A375) melanoma cells. CBD was the most cytotoxic natural cannabinoid with respective IC50 of 28.6 and 51.6 µM. Further assessment of the cytotoxicity of synthetic CBD derivatives in B16F10 cells identified two bipiperidinyl group-bearing derivatives (22 and 34) with enhanced cytotoxicity (IC50 = 3.1 and 8.5 µM, respectively). Furthermore, several cell death assays including flow cytometric (for apoptosis and ferroptosis) and lactate dehydrogenase (for pyroptosis) assays were used to characterize the antiproliferative activity of CBD and its bipiperidinyl derivatives. The augmented cytotoxicity of 22 and 34 in B16F10 cells was attributed to their capacity to promote apoptosis (as evidenced by increased apoptotic population). Taken together, this study supports the notion that CBD and its derivatives are promising lead compounds for cannabinoid-based interventions for melanoma management.

7.
Ethn Health ; : 1-12, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682471

RESUMEN

OBJECTIVES: This study aimed to examine ethnic disparities in the prevalence of diabetes and its association with sleep disorders among the older adults Han and ethnic minority (Bai, Ha Ni, and Dai) population in rural southwest China. METHODS: A cross-sectional survey of 5,642 was conducted among the rural southwest population aged ≥60 years, consisting of a structured interview and measurement of fasting blood glucose, height, weight, and waist circumference. The Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality. RESULTS: The overall prevalence of diabetes and sleep disorder was 10.2% and 40.1%, respectively. Bai participants had the highest prevalence of diabetes (15.9%) and obesity (9.9%)(P < 0.01), while Ha Ni participants had the lowest prevalence of diabetes (5.1%) and obesity (3.4%)(P < 0.01). The highest prevalence of sleep disorder (48.4%) was recorded in Bai participants, while Dai participants had the lowest prevalence of sleep disorder (25.6%)(P < 0.01). In all four studied ethnicities, females had a higher prevalence of sleep disorder than males (P < 0.01), and the prevalence of sleep disorder increased with age (P < 0.01). The results of multivariate logistic regression analysis indicated older adults with sleep disorder had a risk of developing diabetes (P < 0.05). Moreover, the higher educational level, family history of diabetes, and obesity were the main risk factors for diabetes in participants (P < 0.01). CONCLUSION: There are stark ethnic disparities in the prevalence of diabetes and sleep disorders in southwest China. Future diabetes prevention and control strategies should be tailored to address ethnicity, and improving sleep quality may reduce the prevalence of diabetes.

8.
Molecules ; 29(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38675512

RESUMEN

The geometrical structures, relative stabilities, and electronic and magnetic properties of niobium carbon clusters, Nb7Cn (n = 1-7), are investigated in this study. Density functional theory (DFT) calculations, coupled with the Saunders Kick global search, are conducted to explore the structural properties of Nb7Cn (n = 1-7). The results regarding the average binding energy, second-order difference energy, dissociation energy, HOMO-LUMO gap, and chemical hardness highlight the robust stability of Nb7C3. Analysis of the density of states suggests that the molecular orbitals of Nb7Cn primarily consist of orbitals from the transition metal Nb, with minimal involvement of C atoms. Spin density and natural population analysis reveal that the total magnetic moment of Nb7Cn predominantly resides on the Nb atoms. The contribution of Nb atoms to the total magnetic moment stems mainly from the 4d orbital, followed by the 5p, 5s, and 6s orbitals.

9.
Nat Prod Res ; : 1-12, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38486398

RESUMEN

The infection of vibrio is an important cause of huge economic losses in aquaculture industry. At present, antibiotics are mainly used to prevent and reduce the infection of the vibrio, which has accelerated the emergence of multi-drug-resistant strains. New generation alternative anti-vibrio drugs were in urgent to solve this problem. In this study, six compounds (1-6) were isolated from the Streptomyces sp. ZZ741A, a marine-derived Streptomyces variant, including one new compound, 2-carbamoylphenyl isobutyrate (1), five known ones, nocardamine (2), dehydroxynocardamine (3), phenylacetic acid (4), thiophenol (5) and 2,3-dihydroxybenzoic acid (6). The anti-vibriosis assay showed that compounds 2 and 3 had specific inhibition activity against Vibrio vulnificus, Vibrio alginolyticus, and Vibrio parahaemolyticus with the MIC values ranging from 8 to 128 µg/mL. The molecular docking study of their possible mechanism of anti-vibriosis activity showed that the activity might come from the inhibition of Outer membrane protein U (OmpU).

10.
Cell Insight ; 3(2): 100146, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38425643

RESUMEN

The programmed cell death 1 (PD-1) immune checkpoint of co-inhibitory signaling plays crucial roles in controlling the magnitude and duration of T cell activation to limit tissue damage and maintain self-tolerance. Cancer cells hijack the co-inhibitory pathway and escape immune surveillance by overexpressing the PD-1 ligand PD-L1. Immune checkpoint inhibitors, such as PD-1 blocking antibody have been approved for tumor immunotherapy. However, not all patients can benefit from PD-1 monotherapy. Combination immunotherapy based on PD-1 axis blockade substantially improves clinical anti-tumor efficacy. In this review, we briefly summarize the current progress on the mechanisms of PD-1-mediated inhibition of T cell activation and strategies for cancer combination immunotherapy.

11.
J Vis Exp ; (204)2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38465928

RESUMEN

Cationic nanostructures have emerged as an adjuvant and antigen delivery system that enhances dendritic cell maturation, ROS generation, and antigen uptake and then promotes antigen-specific immune responses. In recent years, retinoic acid (RA) has received increasing attention due to its effect in activating the mucosal immune response; however, in order to use RA as a mucosal adjuvant, it is necessary to solve the problem of its dissolution, loading, and delivery. Here, we describe a cationic nanoemulsion-encapsulated retinoic acid (CNE-RA) delivery system composed of the cationic lipid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOTAP), retinoic acid, squalene as the oil phase, polysorbate 80 as surfactant, and sorbitan trioleate 85 as co-surfactant. Its physical and chemical properties were characterized using dynamic light scattering and a spectrophotometer. Immunization of mice with the mixture of antigen (ovalbumin, OVA) and CNE-RA significantly elevated the levels of anti-OVA secretory immunoglobulin A (sIgA) in vaginal lavage fluid and the small intestinal lavage fluid of mice compared with OVA alone. This protocol describes a detailed method for the preparation, characterization, and evaluation of the adjuvant effect of CNE-RA.


Asunto(s)
Adyuvantes Inmunológicos , Inmunización , Femenino , Animales , Ratones , Adyuvantes Inmunológicos/farmacología , Adyuvantes Inmunológicos/química , Membrana Mucosa , Vacunación , Antígenos , Inmunidad Mucosa , Tensoactivos/farmacología , Ovalbúmina , Ratones Endogámicos BALB C
12.
Front Immunol ; 15: 1260191, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38384459

RESUMEN

Background: Intrahepatic cholangiocarcinoma (iCCA) is a highly aggressive cancer with a dismal prognosis and few effective therapeutic approaches. This study aimed to investigate the efficacy, safety, and predictive biomarkers of hepatic arterial infusion chemotherapy (FOLFOX-HAIC) in combination with lenvatinib and PD-1 inhibitor for patients with advanced iCCA. Methods: Locally advanced or metastatic iCCA patients receiving the triple combination therapy of lenvatinib, PD-1 inhibitor, and FOLFOX-HAIC were included in this retrospective study. Primary endpoint was the progression-free survival, evaluated using the RECIST criterion. The secondary endpoints included overall survival, objective response rate, and safety. Whole exome and RNA sequencing of tumor biopsy tissues were performed for biomarker exploration. Results: Between May, 2019 and December 2022, a total of 46 patients were included in this study. The primary endpoint showed a median progression-free survival of 9.40 months (95% CI: 5.28-13.52), with a 6-month progression-free survival rate of 76.1%. The median overall survival was 16.77 months (95% CI, 14.20-19.33), with an objective response rate of 47.8% and disease control rate of 91.3% per RECIST. In addition, 4.3% and 8.7% of patients achieved complete response of all lesions and intrahepatic target lesions per mRECIST, respectively. The most common treatment-related adverse events were neutropenia, thrombocytopenia, elevated aspartate aminotransferase and alanine aminotransferase level. Furthermore, integrated analysis of genetic, transcriptomic, and immunohistochemistry data revealed that pre-existing immunity (high expression level of immune-related signatures and intra-tumoral CD8+ T cell density) in baseline tumor tissues was associated with superior clinical benefits. However, the evaluation of tumor mutation burden did not show potential predictive value in this triple combination. Conclusion: FOLFOX-HAIC in combination with lenvatinib and PD-1 inhibitor demonstrated a promising antitumor activity with manageable safety profiles in patients with advanced iCCA. Moreover, our study also revealed new perspectives on potential biomarkers for clinical efficacy.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Leucopenia , Compuestos de Fenilurea , Quinolinas , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Estudios Retrospectivos , Colangiocarcinoma/tratamiento farmacológico , Colangiocarcinoma/genética , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Neoplasias de los Conductos Biliares/genética , Conductos Biliares Intrahepáticos
13.
J Integr Plant Biol ; 66(4): 638-641, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38351739

RESUMEN

The compact CRISPR/CasΦ2 system provides a complementary genome engineering tool for efficient gene editing including cytosine and adenosine base editing in wheat and rye with high specificity, efficient use of the protospacer-adjacent motif TTN, and an alternative base-editing window.


Asunto(s)
Edición Génica , Triticum , Triticum/genética , Sistemas CRISPR-Cas/genética , Secale/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas
14.
J Nat Prod ; 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373879

RESUMEN

Skin cells are susceptible to oxidative stress and various types of cell death, including an iron-dependent form known as ferroptosis. Cannabidiol (CBD) can protect skin cells against oxidative stress, but whether this is attributed to the inhibition of ferroptosis is unknown. Herein, we evaluated the anti-ferroptotic effect of CBD in human keratinocytes using biochemical assays (radical scavenging and iron chelating) and cell-based models (for lipid peroxidation and intracellular iron). CBD's anti-ferroptotic effect was further characterized by proteomic analysis. This study identifies anti-ferroptosis as a mechanism of CBD's skin protective effects.

16.
BMC Biol ; 22(1): 31, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38317190

RESUMEN

BACKGROUND: The duck (Anas platyrhynchos) is one of the principal natural hosts of influenza A virus (IAV), harbors almost all subtypes of IAVs and resists to many IAVs which cause extreme virulence in chicken and human. However, the response of duck's adaptive immune system to IAV infection is poorly characterized due to lack of a detailed gene map of the major histocompatibility complex (MHC). RESULTS: We herein reported a chromosome-scale Beijing duck assembly by integrating Nanopore, Bionano, and Hi-C data. This new reference genome SKLA1.0 covers 40 chromosomes, improves the contig N50 of the previous duck assembly with highest contiguity (ZJU1.0) of more than a 5.79-fold, surpasses the chicken and zebra finch references in sequence contiguity and contains a complete genomic map of the MHC. Our 3D MHC genomic map demonstrated that gene family arrangement in this region was primordial; however, families such as AnplMHCI, AnplMHCIIß, AnplDMB, NKRL (NK cell receptor-like genes) and BTN underwent gene expansion events making this area complex. These gene families are distributed in two TADs and genes sharing the same TAD may work in a co-regulated model. CONCLUSIONS: These observations supported the hypothesis that duck's adaptive immunity had been optimized with expanded and diversified key immune genes which might help duck to combat influenza virus. This work provided a high-quality Beijing duck genome for biological research and shed light on new strategies for AIV control.


Asunto(s)
Patos , Genoma , Animales , Humanos , Patos/genética , Complejo Mayor de Histocompatibilidad/genética , Cromosomas/genética , Familia de Multigenes
17.
Microbiol Spectr ; 12(2): e0200223, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38193726

RESUMEN

Marine ecosystems contain an immense diversity of phages, many of which infect cyanobacteria (cyanophage) that are largely responsible for primary productivity. To characterize the genetic diversity and biogeographic distribution of the marine T4-like cyanophage community in the northern South China Sea, the T4-like cyanophage portal protein gene (g20) was amplified. Phylogenetic analysis revealed that marine T4-like cyanophages were highly diverse, with g20 operational taxonomic units being affiliated with five defined clades (Clusters I-V). Cluster II had a wide geographic distribution, Cluster IV was the most abundant in the open sea, and Cluster I was dominant in coastal shelf environments. Our results showed T4-like cyanophages (based on g20) community was generally shaped via heterogeneous selection. Highly variable environmental factors (such as salinity and temperature) can heterogeneously select different cyanophage communities. Nevertheless, the dominant drivers of the T4-like cyanophage community based on the g20 and g23 (T4-like phage major capsid protein gene) were different, probably due to different coverages by the primer sets. Furthermore, the community assembly processes of T4-like cyanophages were affected by host traits (abundance and distribution), viral traits (latent period, burst size, and host range), and environmental properties (temperature and salinity).IMPORTANCECyanophages are abundant and ubiquitous in the oceans, altering population structures and evolution of cyanobacteria, which account for a large portion of global carbon fixation, through host mortality, horizontal gene transfer, and the modulation of host metabolism. However, little is known about the biogeography and ecological drivers that shape the cyanophage community. Here, we use g20 and g23 genes to examine the biogeographic patterns and the assembly mechanisms of T4-like cyanophage community in the northern part of the South China Sea. The different coverages of primer sets might lead to the different dominant drivers of T4-like cyanophage community based on g20 and g23 genes. Our results showed that characteristics of viral traits (latent period, burst size, and host range) and host traits (abundance and distribution) were found to either limit or enhance the biogeographic distribution of T4-like cyanophages. Overall, both virus and host properties are critical to consider when determining rules of community assembly for viruses.


Asunto(s)
Bacteriófagos , Cianobacterias , Filogenia , Ecosistema , Bacteriófagos/genética , Proteínas de la Cápside/genética , Cápside
18.
J Comput Chem ; 45(14): 1087-1097, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38243618

RESUMEN

A series of pentagonal bipyramidal anionic germanium clusters doped with heavy rare earth elements, REGe 6 - (RE = Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), have been identified at the PBE0/def2-TZVP level using density functional theory (DFT). Our findings reveal that the centrally doped pentagonal ring structure demonstrates enhanced stability and heightened aromaticity due to its uniform bonding characteristics and a larger charge transfer region. Through natural population analysis and spin density diagrams, we observed a monotonic decrease in the magnetic moment from Gd to Yb. This is attributed to the decreasing number of unpaired electrons in the 4f orbitals of the heavy rare earth atoms. Interestingly, the system doped with Er atoms showed lower stability and anti-aromaticity, likely due to the involvement of the 4f orbitals in bonding. Conversely, the systems doped with Gd and Tb atoms stood out for their high magnetism and stability, making them potential building blocks for rare earth-doped semiconductor materials.

19.
Artículo en Inglés | MEDLINE | ID: mdl-38261502

RESUMEN

The task of instance segmentation in remote sensing images, aiming at performing per-pixel labeling of objects at the instance level, is of great importance for various civil applications. Despite previous successes, most existing instance segmentation methods designed for natural images encounter sharp performance degradations when they are directly applied to top-view remote sensing images. Through careful analysis, we observe that the challenges mainly come from the lack of discriminative object features due to severe scale variations, low contrasts, and clustered distributions. In order to address these problems, a novel context aggregation network (CATNet) is proposed to improve the feature extraction process. The proposed model exploits three lightweight plug-and-play modules, namely, dense feature pyramid network (DenseFPN), spatial context pyramid (SCP), and hierarchical region of interest extractor (HRoIE), to aggregate global visual context at feature, spatial, and instance domains, respectively. DenseFPN is a multi-scale feature propagation module that establishes more flexible information flows by adopting interlevel residual connections, cross-level dense connections, and feature reweighting strategy. Leveraging the attention mechanism, SCP further augments the features by aggregating global spatial context into local regions. For each instance, HRoIE adaptively generates RoI features for different downstream tasks. Extensive evaluations of the proposed scheme on iSAID, DIOR, NWPU VHR-10, and HRSID datasets demonstrate that the proposed approach outperforms state-of-the-arts under similar computational costs. Source code and pretrained models are available at https://github.com/yeliudev/CATNet.

20.
Phys Chem Chem Phys ; 26(4): 2986-2994, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38163990

RESUMEN

Rare earth elements have high chemical reactivity, and doping them into semiconductor clusters can induce novel physicochemical properties. The study of the physicochemical mechanisms of interactions between rare earth and tin atoms will enhance our understanding of rare earth functional materials from a microscopic perspective. Hence, the structure, electronic characteristics, stability, and aromaticity of endohedral cages MSn16- (M = Sc, Y, La) have been investigated using a combination of the hybrid PBE0 functional, stochastic kicking, and artificial bee colony global search technology. By comparing the simulated results with experimental photoelectron spectra, it is determined that the most stable structure of these clusters is the Frank-Kasper polyhedron. The doping of atoms has a minimal influence on density of states of the pure tin system, except for causing a widening of the energy gap. Various methods such as ab initio molecular dynamics simulations, the spherical jellium model, adaptive natural density partitioning, localized orbital locator, and electron density difference are employed to analyze the stability of these clusters. The aromaticity of the clusters is examined using iso-chemical shielding surfaces and the gauge-including magnetically induced currents. This study demonstrates that the stability and aromaticity of a tin cage can be systematically adjusted through doping.

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