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2.
Front Microbiol ; 15: 1387401, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38860223

RESUMO

Background: Intestinal microbiota have been demonstrated to be involved in the development of NAFLD, while the relationship between the severity of NAFLD and intestinal microbiota is still not fully elucidated. Sheng-Jiang Powder (SJP) showed exact efficacy in treating SFL and great potential in regulating intestinal microbiota, but the effects need to be further addressed in NASH and liver fibrosis. Objectives: To investigate the differences in intestinal microbiota of NAFLD with different severity and the effect of SJP on liver damage and intestinal microbiota. Design: NAFLD mice models with different severity were induced by high-fat diet (HFD) or choline-deficient, L-amino acid-defined high-fat diet (CDAHFD) feeding and then treated with SJP/normal saline. Methods: Biochemical blood tests, H&E/Masson/Oil Red O/IHC staining, Western blot, and 16SrDNA sequencing were performed to explore intestinal microbiota alteration in different NAFLD models and the effect of SJP on liver damage and intestinal microbiota. Results: Intestinal microbiota alteration was detected in all NAFLD mice. SJP induced increased expression of Pparγ and alleviated liver lipid deposition in all NAFLD mice. Microbiome analysis revealed obvious changes in intestinal microbiota composition, while SJP significantly elevated the relative abundance of Roseburia and Akkermansia, which were demonstrated to be beneficial for improving inflammation and intestinal barrier function. Conclusion: Our results demonstrated that SJP was effective in improving lipid metabolism in NAFLD mice, especially in mice with SFL. The potential mechanism may be associated with the regulation of intestinal microbiota.

3.
Int Immunopharmacol ; 136: 112316, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38823183

RESUMO

The objective of this study was to investigate the neuroimmune mechanisms implicated in the enhancement of gastrointestinal function through the administration of oral DHA. Mast cell-deficient mice (KitW-sh) and C57BL/6 mice were used to establish postoperative ileus (POI) models. To further validate our findings, we conducted noncontact coculture experiments involving dorsal root ganglion (DRG) cells, bone marrow-derived mast cells (BMMCs) and T84 cells. Furthermore, the results obtained from investigations conducted on animals and cells were subsequently validated through clinical trials. The administration of oral DHA had ameliorative effects on intestinal barrier injury and postoperative ileus. In a mechanistic manner, the anti-inflammatory effect of DHA was achieved through the activation of transient receptor potential ankyrin 1 (TRPA1) on DRG cells, resulting in the stabilization of mast cells and increasing interleukin 10 (IL-10) secretion in mast cells. Furthermore, the activation of the pro-repair WNT1-inducible signaling protein 1 (WISP-1) signaling pathways by mast cell-derived IL-10 resulted in an enhancement of the intestinal barrier integrity. The current study demonstrated that the neuroimmune interaction between mast cells and nerves played a crucial role in the process of oral DHA improving the intestinal barrier integrity of POI, which further triggered the activation of CREB/WISP-1 signaling in intestinal mucosal cells.


Assuntos
Ácidos Docosa-Hexaenoicos , Íleus , Interleucina-10 , Mucosa Intestinal , Mastócitos , Camundongos Endogâmicos C57BL , Complicações Pós-Operatórias , Canal de Cátion TRPA1 , Animais , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Docosa-Hexaenoicos/uso terapêutico , Canal de Cátion TRPA1/metabolismo , Camundongos , Íleus/tratamento farmacológico , Íleus/imunologia , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Masculino , Interleucina-10/metabolismo , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/imunologia , Gânglios Espinais/metabolismo , Gânglios Espinais/efeitos dos fármacos , Modelos Animais de Doenças , Técnicas de Cocultura , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico
4.
Sci Adv ; 10(23): eadk9996, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38838152

RESUMO

Immunotoxicity remains a major hindrance to chemotherapy in cancer therapy. Nanocarriers may alleviate the immunotoxicity, but the optimal design remains unclear. Here, we created two variants of maytansine (DM1)-loaded synthetic high-density lipoproteins (D-sHDL) with either physically entrapped (ED-sHDL) or chemically conjugated (CD-sHDL) DM1. We found that CD-sHDL showed less accumulation in the tumor draining lymph nodes (DLNs) and femur, resulting in a lower toxicity against myeloid cells than ED-sHDL via avoiding scavenger receptor class B type 1 (SR-B1)-mediated DM1 transportation into the granulocyte-monocyte progenitors and dendritic cells. Therefore, higher densities of lymphocytes in the tumors, DLNs, and blood were recorded in mice receiving CD-sHDL, leading to a better efficacy and immune memory of CD-sHDL against colon cancer. Furthermore, liposomes with conjugated DM1 (CD-Lipo) showed lower immunotoxicity than those with entrapped drug (ED-Lipo) through the same mechanism after apolipoprotein opsonization. Our findings highlight the critical role of drug loading patterns in dictating the biological fate and activity of nanomedicine.


Assuntos
Nanopartículas , Animais , Nanopartículas/química , Camundongos , Linhagem Celular Tumoral , Humanos , Receptores Depuradores Classe B/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Lipoproteínas HDL/metabolismo , Portadores de Fármacos/química , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/imunologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Lipossomos/química , Lipídeos/química
5.
Front Immunol ; 15: 1353695, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38765004

RESUMO

Objectives: This study aimed to analyze active compounds and signaling pathways of CH applying network pharmacology methods, and to additionally verify the molecular mechanism of CH in treating AP. Materials and methods: Network pharmacology and molecular docking were firstly used to identify the active components of CH and its potential targets in the treatment of AP. The pancreaticobiliary duct was retrogradely injected with sodium taurocholate (3.5%) to create an acute pancreatitis (AP) model in rats. Histological examination, enzyme-linked immunosorbent assay, Western blot and TUNEL staining were used to determine the pathway and mechanism of action of CH in AP. Results: Network pharmacological analysis identified 168 active compounds and 276 target proteins. In addition, there were 2060 targets associated with AP, and CH had 177 targets in common with AP. These shared targets, including STAT3, IL6, MYC, CDKN1A, AKT1, MAPK1, MAPK3, MAPK14, HSP90AA1, HIF1A, ESR1, TP53, FOS, and RELA, were recognized as core targets. Furthermore, we filtered out 5252 entries from the Gene Ontology(GO) and 186 signaling pathways from the Kyoto Encyclopedia of Genes and Genomes(KEGG). Enrichment and network analyses of protein-protein interactions predicted that CH significantly affected the PI3K/AKT signaling pathway, which played a critical role in programmed cell death. The core components and key targets showed strong binding activity based on molecular docking results. Subsequently, experimental validation demonstrated that CH inhibited the phosphorylation of PI3K and AKT in pancreatic tissues, promoted the apoptosis of pancreatic acinar cells, and further alleviated inflammation and histopathological damage to the pancreas in AP rats. Conclusion: Apoptosis of pancreatic acinar cells can be enhanced and the inflammatory response can be reduced through the modulation of the PI3K/AKT signaling pathway, resulting in the amelioration of pancreatic disease.


Assuntos
Medicamentos de Ervas Chinesas , Simulação de Acoplamento Molecular , Farmacologia em Rede , Pancreatite , Transdução de Sinais , Animais , Pancreatite/tratamento farmacológico , Pancreatite/metabolismo , Pancreatite/patologia , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/química , Ratos , Transdução de Sinais/efeitos dos fármacos , Masculino , Modelos Animais de Doenças , Apoptose/efeitos dos fármacos , Ratos Sprague-Dawley , Mapas de Interação de Proteínas
6.
Heliyon ; 10(9): e29849, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38699021

RESUMO

Background: Rheumatoid arthritis is a systemic inflammatory autoimmune disease that severely impacts physical and mental health. Autophagy is a cellular process involving the degradation of cellular components in lysosomes. However, from a bioinformatics perspective, autophagy-related genes have not been comprehensively elucidated in rheumatoid arthritis. Methods: In this study, we performed differential analysis of autophagy-related genes in rheumatoid arthritis patients using the GSE93272 dataset from the Gene Expression Omnibus database. Marker genes were screened by least absolute shrinkage and selection operator. Based on marker genes, we used unsupervised cluster analysis to elaborate different autophagy clusters, and further identified modules strongly associated with rheumatoid arthritis by weighted gene co-expression network analysis. In addition, we constructed four machine learning models, random forest model, support vector machine model, generalized linear model and extreme gradient boosting based on marker genes, and based on the optimal machine learning model, a nomogram model was constructed for distinguishing between normal individuals and rheumatoid arthritis patients. Finally, five external independent rheumatoid arthritis datasets were used for the validation of our results. Results: The results showed that autophagy-related genes had significant expression differences between normal individuals and osteoarthritis patients. Through least absolute shrinkage and selection operator screening, we identified 31 marker genes and found that they exhibited significant synergistic or antagonistic effects in rheumatoid arthritis, and immune cell infiltration analysis revealed significant changes in immune cell abundance. Subsequently, we elaborated different autophagy clusters (cluster 1 and cluster 2) using unsupervised cluster analysis. Next, further by weighted gene co-expression network analysis, we identified a brown module strongly associated with rheumatoid arthritis. In addition, we constructed a nomogram model for five marker genes (CDKN2A, TP53, ATG16L2, FKBP1A, and GABARAPL1) based on a generalized linear model (area under the curve = 1.000), and the predictive efficiency and accuracy of this nomogram model were demonstrated in the calibration curves, the decision curves and the five external independent datasets were validated. Conclusion: This study identified marker autophagy-related genes in rheumatoid arthritis and analyzed their impact on the disease, providing new perspectives for understanding the role of autophagy-related genes in rheumatoid arthritis and providing new directions for its individualized treatment.

8.
Trends Plant Sci ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38763842

RESUMO

Undifferentiated plant and animal stem cells are essential for cell, tissue, and organ differentiation, development, and growth. They possess unusual antiviral immunity which differs from that in specialized cells. By comparison to animal stem cells, we discuss how plant stem cells defend against viral invasion and beyond.

9.
Cell Death Differ ; 31(6): 779-791, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38654072

RESUMO

Cell plasticity has been found to play a critical role in tumor progression and therapy resistance. However, our understanding of the characteristics and markers of plastic cellular states during cancer cell lineage transition remains limited. In this study, multi-omics analyses show that prostate cancer cells undergo an intermediate state marked by Zeb1 expression with epithelial-mesenchymal transition (EMT), stemness, and neuroendocrine features during the development of neuroendocrine prostate cancer (NEPC). Organoid-formation assays and in vivo lineage tracing experiments demonstrate that Zeb1+ epithelioid cells are putative cells of origin for NEPC. Mechanistically, Zeb1 transcriptionally regulates the expression of several key glycolytic enzymes, thereby predisposing tumor cells to utilize glycolysis for energy metabolism. During this process, lactate accumulation-mediated histone lactylation enhances chromatin accessibility and cellular plasticity including induction of neuro-gene expression, which promotes NEPC development. Collectively, Zeb1-driven metabolic rewiring enables the epigenetic reprogramming of prostate cancer cells to license the adeno-to-neuroendocrine lineage transition.


Assuntos
Neoplasias da Próstata , Homeobox 1 de Ligação a E-box em Dedo de Zinco , Masculino , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Humanos , Animais , Cromatina/metabolismo , Transição Epitelial-Mesenquimal , Linhagem Celular Tumoral , Camundongos , Regulação Neoplásica da Expressão Gênica , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/genética , Plasticidade Celular , Glicólise , Montagem e Desmontagem da Cromatina
10.
Pestic Biochem Physiol ; 201: 105862, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685239

RESUMO

Phomopsis longicolla, a causal agent of soybean root rot, stem blight, seed decay, pod and stem canker, which seriously affects the yield and quality of soybean production worldwide. The phenylpyrrole fungicide fludioxonil exhibits a broad spectrum and high activity against phytopathogenic fungi. In this study, the baseline sensitivity of 100 P. longicolla isolates collected from the main soybean production areas of China to fludioxonil were determined. The result showed that the EC50 values of all the P. longicolla isolates ranged from 0.013 to 0.035 µg/ml. Furthermore, 12 fludioxonil-resistance (FluR) mutants of P. longicolla were generated from 6 fludioxonil-sensitive (FluS) isolates. and the resistance factors (RF) of 12 FluR mutants were >3500. Sequence alignment showed that multiple mutation types were found in PlOS1, PlOS4 or/and PlOS5 of FluR mutants. All the FluR mutants exhibited fitness penalty in mycelial growth, conidiation, virulence and osmo-adaptation. Under fludioxonil or NaCl treatment condition, the glycerol accumulation was significantly increased in FluS isolates, but was slightly increased in FluR mutants, and the phosphorylation level of most FluR mutants was significantly decreased when compared to the FluS isolates. Additionally, positive cross-resistance was observed between fludioxonil and procymidone but not fludioxonil and pydiflumetofen, pyraclostrobin or fluazinam. This is first reported that the baseline sensitivity of P. longicolla to fludioxonil, as well as the biological and molecular characterizations of P. longicolla FluR mutants to fludioxonil. These results can provide scientific directions for controlling soybean diseases caused by P. longicolla using fludioxonil.


Assuntos
Ascomicetos , Dioxóis , Farmacorresistência Fúngica , Fungicidas Industriais , Pirróis , Pirróis/farmacologia , Fungicidas Industriais/farmacologia , Farmacorresistência Fúngica/genética , Dioxóis/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/genética , Ascomicetos/metabolismo , Mutação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Doenças das Plantas/microbiologia , Glycine max/microbiologia , Glycine max/efeitos dos fármacos
12.
BMC Urol ; 24(1): 101, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689249

RESUMO

BACKGROUND: To introduce the surgical technique and our team's extensive experience with tunnel method in laparoscopic adrenalectomy. METHODS: From July 2019 to June 2022, we independently designed and conducted 83 cases of " Tunnel Method Laparoscopic Adrenalectomy," a prospective study. There were 45 male and 38 female patients, ages ranged from 25 to 73 years(mean: 44.6 years).The cases included 59 adrenal cortical adenomas, 9 pheochromocytomas, 6 cysts, 4 myelolipomas, 1 ganglioneuroma, and 4 cases of adrenal cortical hyperplasia. In terms of anatomical location, there were 39 cases on the left side, 42 on the right side, and 2 bilateral cases. Tumor diameters ranged from 0.6 to 5.9 cm(mean: 2.9 cm). Utilizing ultrasound monitoring, percutaneous puncture was made either directly to the target organ or its vicinity, and the puncture path was manually marked. Then, under the direct view of a single-port single-channel laparoscope, the path to the target organ in the retroperitoneum or its vicinity was further delineated and separated. This approach allowed for the insertion of the laparoscope and surgical instruments through the affected adrenal gland, thereby separating the surface of the target organ to create sufficient operational space for the adrenalectomy. RESULTS: All 83 surgeries were successfully completed. A breakdown of the surgical approach reveals that 51 surgeries were done using one puncture hole, 25 with two puncture holes, and 7 with three puncture holes. The operation time ranged from 31 to 105 min (mean: 47 min), with a blood loss of 10 to 220mL (mean: 40 mL). Notably, there were no conversions to open surgery and no intraoperative complications. Postoperative follow-up ranged from 6 to 28 months, during which after re-examination using ultrasound, CT, and other imaging methods, there were no recurrences or other complications detected. CONCLUSIONS: The completion of the tunnel method laparoscopic adrenalectomy represents a breakthrough, transitioning from the traditional step-by-step separation of retroperitoneal tissues to reach the target organ in conventional retroperitoneoscopic surgery. This method directly accesses the target organ, substantially reducing the damage and complications associated with tissue separation in retroperitoneoscopic surgery, As a result, it provides a new option for minimally invasive surgery of retroperitoneal organs and introduces innovative concepts to retroperitoneoscopic surgery.


Assuntos
Adrenalectomia , Laparoscopia , Humanos , Adrenalectomia/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Laparoscopia/métodos , Adulto , Idoso , Espaço Retroperitoneal/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem
13.
Biomacromolecules ; 25(5): 2953-2964, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38652682

RESUMO

Endoscopic submucosal dissection (ESD) is an effective method for resecting early-stage tumors in the digestive system. To achieve a low injection pressure of the injected fluid and continuous elevation of the mucosa following injection during the ESD technique, we introduced an innovative injectable sodium-alginate-based drug-loaded microsphere (Cipro-ThSA) for ESD surgery, which was generated through an emulsion reaction involving cysteine-modified sodium alginate (ThSA) and ciprofloxacin. Cipro-ThSA microspheres exhibited notable adhesiveness, antioxidant activity, and antimicrobial properties, providing a certain level of postoperative wound protection. In vitro cell assays confirmed the decent biocompatibility of the material. Lastly, according to animal experiments involving submucosal elevation of porcine colons, Cipro-ThSA microspheres ensure surgically removable lift height while maintaining the mucosa for approximately 246% longer than saline, which could effectively reduce surgical risks while providing sufficient time for operation. Consequently, the Cipro-ThSA microsphere holds great promise as a novel submucosal injection material, in terms of enhancing the operational safety and effectiveness of ESD surgery.


Assuntos
Alginatos , Ressecção Endoscópica de Mucosa , Microesferas , Alginatos/química , Animais , Suínos , Ressecção Endoscópica de Mucosa/métodos , Humanos , Ciprofloxacina/administração & dosagem , Ciprofloxacina/química , Ciprofloxacina/farmacologia , Cisteína/química
14.
J Fungi (Basel) ; 10(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38667920

RESUMO

Penicillium digitatum is a major postharvest pathogen that threatens the global citrus fruit industry and causes great economic losses annually. In the present study, inhibitory properties of cinnamon bark oil (CBO) against P. digitatum in vitro were investigated. Results indicated that 0.03% CBO could efficiently inhibit the spore germination, germ tube elongation, mycelial growth, colonial expansion and conidial accumulation of P. digitatum. The results of fluorescein diacetate (FDA) and MitoTraker Orange (MTO) staining also proved the suppression effects of CBO against P. digitatum. Meanwhile, CBO could inhibit green mold rots induced by P. digitatum in citrus fruit when the working concentration of CBO exceeded 0.06%. In addition, the expressions of 12 genes critical for the growth and virulence of P. digitatum were also significantly regulated under CBO stress. Through a transcriptomic analysis, a total of 1802 common differentially expressed genes (DEGs) were detected in P. digitatum after 4 h and 8 h of CBO treatment. Most of the DEG products were associated with carbohydrate, amino acid and lipid metabolism. They directly or indirectly led to the disturbance of the membrane and the generation of reactive oxygen species (ROS). Our results may deepen the understanding of antifungal properties of CBO against P. digitatum and provide the theoretical foundation to uncover the antifungal mechanism of CBO at the molecular level.

15.
J Xray Sci Technol ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38669513

RESUMO

BACKGROUND: Recently, X-rays have been widely used to detect complex structural workpieces. Due to the uneven thickness of the workpiece and the high dynamic range of the X-ray image itself, the detailed internal structure of the workpiece cannot be clearly displayed. OBJECTIVE: To solve this problem, we propose an image enhancement algorithm based on a multi-scale local edge-preserving filter. METHODS: Firstly, the global brightness of the image is enhanced through logarithmic transformation. Then, to enhance the local contrast, we propose utilizing the gradient decay function based on fuzzy entropy to process the gradient and then incorporate the gradient into the energy function of the local edge-preserving filter (LEP) as a constraint term. Finally, multiple base layers and detail layers are obtained through filtering multi-scale decomposition. All detail layers are enhanced and fused using S-curve mapping to improve contrast further. RESULTS: This method is competitive in both quantitative indices and visual perception quality. CONCLUSIONS: The experimental results demonstrate that the proposed method significantly enhances various complex workpieces and is highly efficient.

16.
J Hazard Mater ; 469: 134079, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38521042

RESUMO

The removal and recovery of radioactive Sr(II) from wastewater and seawater has been of great concern due to the negative environmental impacts of nuclear energy development and the potential risk of nuclear accidents. Herein, a facile molten salt synthesis strategy was developed to systematically investigated the reaction of different types of MXenes with nitrates. Among the products, K+ intercalated hierarchical titanate nanostructures (K-HTNs) obtained from the direct chemical transformation of multilayered Ti3C2Tx exhibited unique layered structures, good physicochemical properties, and outstanding adsorption performance for Sr(II). The maximum adsorption capacity of Sr(II) by K-HTNs reached 204 mg·g-1 at ambient temperature, and the good regeneration and reusability of the titanate was also demonstrated. K-HTNs showed preferential selectivity for Sr(II) in different environmental media containing competing ions, and the removal efficiency of Sr(II) in real seawater was as high as 93.3 %. The removal mechanism was elaborated to be the exchange of Sr2+ with K+/H+ in the interlayers of K-HTNs, and the adsorbed Sr(II) had a strong interaction with Ti-O- termination on the titanate surface. Benefiting from the merits of rapid and scalable synthesis and excellent adsorption performance, MXene-derived K-HTNs have broad application prospects for the purification of 90Sr-contaminated wastewater and seawater.

17.
Biomacromolecules ; 25(4): 2222-2242, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38437161

RESUMO

Recent strides in molecular pathology have unveiled distinctive alterations at the molecular level throughout the onset and progression of diseases. Enhancing the in vivo visualization of these biomarkers is crucial for advancing disease classification, staging, and treatment strategies. Peptide-based molecular probes (PMPs) have emerged as versatile tools due to their exceptional ability to discern these molecular changes with unparalleled specificity and precision. In this Perspective, we first summarize the methodologies for crafting innovative functional peptides, emphasizing recent advancements in both peptide library technologies and computer-assisted peptide design approaches. Furthermore, we offer an overview of the latest advances in PMPs within the realm of biological imaging, showcasing their varied applications in diagnostic and therapeutic modalities. We also briefly address current challenges and potential future directions in this dynamic field.


Assuntos
Sondas Moleculares , Peptídeos , Peptídeos/química , Diagnóstico por Imagem/métodos , Biomarcadores
18.
Nat Commun ; 15(1): 2313, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485978

RESUMO

Arising from the extreme/saddle point in electronic bands, Van Hove singularity (VHS) manifests divergent density of states (DOS) and induces various new states of matter such as unconventional superconductivity. VHS is believed to exist in one and two dimensions, but rarely found in three dimension (3D). Here, we report the discovery of 3D VHS in a topological magnet EuCd2As2 by magneto-infrared spectroscopy. External magnetic fields effectively control the exchange interaction in EuCd2As2, and shift 3D Weyl bands continuously, leading to the modification of Fermi velocity and energy dispersion. Above the critical field, the 3D VHS forms and is evidenced by the abrupt emergence of inter-band transitions, which can be quantitatively described by the minimal model of Weyl semimetals. Three additional optical transitions are further predicted theoretically and verified in magneto-near-infrared spectra. Our results pave the way to exploring VHS in 3D systems and uncovering the coordination between electronic correlation and the topological phase.

19.
Comput Biol Med ; 173: 108378, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554660

RESUMO

Low-dose computed tomography (LDCT) has been widely concerned in the field of medical imaging because of its low radiation hazard to humans. However, under low-dose radiation scenarios, a large amount of noise/artifacts are present in the reconstructed image, which reduces the clarity of the image and is not conducive to diagnosis. To improve the LDCT image quality, we proposed a combined frequency separation network and Transformer (FSformer) for LDCT denoising. Firstly, FSformer decomposes the LDCT images into low-frequency images and multi-layer high-frequency images by frequency separation blocks. Then, the low-frequency components are fused with the high-frequency components of different layers to remove the noise in the high-frequency components with the help of the potential texture of low-frequency parts. Next, the estimated noise images can be obtained by using Transformer stage in the frequency aggregation denoising block. Finally, they are fed into the reconstruction prediction block to obtain improved quality images. In addition, a compound loss function with frequency loss and Charbonnier loss is used to guide the training of the network. The performance of FSformer has been validated and evaluated on AAPM Mayo dataset, real Piglet dataset and clinical dataset. Compared with previous representative models in different architectures, FSformer achieves the optimal metrics with PSNR of 33.7714 dB and SSIM of 0.9254 on Mayo dataset, the testing time is 1.825 s. The experimental results show that FSformer is a state-of-the-art (SOTA) model with noise/artifact suppression and texture/organization preservation. Moreover, the model has certain robustness and can effectively improve LDCT image quality.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Animais , Humanos , Suínos , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
20.
Environ Sci Pollut Res Int ; 31(17): 25508-25523, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38472581

RESUMO

Quantifying the drivers of water footprint evolution in the Yangtze River Delta is vital for the optimization of China's total water consumption. The article aims to decompose and predict the water footprint of the Yangtze River Delta and provide policy recommendations for optimizing water use in the Yangtze River Delta. The paper applies the LMDI method to decompose the water footprint of the Yangtze River Delta and its provinces into five major drivers: water footprint structure, water use intensity, R&D scale, R&D efficiency, and population size. Furthermore, this paper combines scenario analysis and Monte Carlo simulation methods to predict the potential evolution trends of water footprint under the basic, general, and enhanced water conservation scenario, respectively. The results show that (1) the expansion of R&D scale is the main factor promoting the growth of water footprint, the improvement of R&D efficiency, and the reduction of water intensity are the main factors inhibiting the increase of water footprint, and the water footprint structure and population size have less influence on water footprint. (2) The evolution trend of water footprint of each province under three scenarios is different. Compared to the basic scenario, the water footprint decreases more in Shanghai, Zhejiang, and Anhui under the general and enhanced water conservation scenario. The increase in water footprint in Jiangsu under the enhanced scenario is smaller than that of the general water conservation scenario.


Assuntos
Conservação dos Recursos Hídricos , Rios , China , Água , Previsões , Desenvolvimento Econômico
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