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1.
Photoacoustics ; 38: 100610, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38726025

RESUMO

Expansion microscopy (ExM) is a promising technology that enables nanoscale imaging on conventional optical microscopes by physically magnifying the specimens. Here, we report the development of a strategy that enables i) on-demand labeling of subcellular organelles in live cells for ExM through transfection of fluorescent proteins that are well-retained during the expansion procedure; and ii) non-fluorescent chromogenic color-development towards efficient bright-field and photoacoustic imaging in both planar and volumetric formats, which is applicable to both cultured cells and biological tissues. Compared to the conventional ExM methods, our strategy provides an expanded toolkit, which we term as expansion fluorescence and photoacoustic microscopy (ExFLPAM), by allowing on-demand fluorescent protein labeling of cultured cells, as well as non-fluorescent absorption contrast-imaging of biological samples.

2.
Diabetes Metab Res Rev ; 40(4): e3809, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38708843

RESUMO

Diabetic kidney disease (DKD), one of the common microvascular complications of diabetes, is increasing in prevalence worldwide and can lead to End-stage renal disease. However, there are still gaps in our understanding of the pathophysiology of DKD, and both current clinical diagnostic methods and treatment strategies have drawbacks. According to recent research, long non-coding RNAs (lncRNAs) are intimately linked to the developmental process of DKD and could be viable targets for clinical diagnostic decisions and therapeutic interventions. Here, we review recent insights gained into lncRNAs in pathological changes of DKD such as mesangial expansion, podocyte injury, renal tubular injury, and interstitial fibrosis. We also discuss the clinical applications of DKD-associated lncRNAs as diagnostic biomarkers and therapeutic targets, as well as their limitations and challenges, to provide new methods for the prevention, diagnosis, and treatment of DKD.


Assuntos
Nefropatias Diabéticas , RNA Longo não Codificante , Humanos , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/genética , RNA Longo não Codificante/fisiologia , RNA Longo não Codificante/genética , Biomarcadores/análise , Animais , Podócitos/patologia , Podócitos/metabolismo
3.
Neuron ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38701790

RESUMO

Multiple system atrophy (MSA) is an adult-onset, sporadic synucleinopathy characterized by parkinsonism, cerebellar ataxia, and dysautonomia. The genetic architecture of MSA is poorly understood, and treatments are limited to supportive measures. Here, we performed a comprehensive analysis of whole genome sequence data from 888 European-ancestry MSA cases and 7,128 controls to systematically investigate the genetic underpinnings of this understudied neurodegenerative disease. We identified four significantly associated risk loci using a genome-wide association study approach. Transcriptome-wide association analyses prioritized USP38-DT, KCTD7, and lnc-KCTD7-2 as novel susceptibility genes for MSA within these loci, and single-nucleus RNA sequence analysis found that the associated variants acted as cis-expression quantitative trait loci for multiple genes across neuronal and glial cell types. In conclusion, this study highlights the role of genetic determinants in the pathogenesis of MSA, and the publicly available data from this study represent a valuable resource for investigating synucleinopathies.

4.
Sci Rep ; 14(1): 11581, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773247

RESUMO

The (3 + 1)-dimensional Painlevé integrable equation are a class of nonlinear differential equations with special properties, which play an important role in nonlinear science and are of great significance in solving various practical problems, such as many important models in fields such as quantum mechanics, statistical physics, nonlinear optics, and celestial mechanics. In this work, we utilize the Hirota bilinear form and Mathematica software to formally obtain the interaction solution among lump wave, solitary wave and periodic wave, which has not yet appeared in other literature. Additionally, using the ( G ' / G ) -expansion method, we provide a rich set of exact solutions for the (3 + 1)-dimensional Painlevé integrable equation, which includes two functions with arbitrary values. This method is the first to be applied to the (3 + 1)-dimensional Painlevé integrable equation. By giving some 3D graphics and density maps, the dynamic properties are analyzed and demonstrated, which is beneficial for promoting understanding and application of the (3 + 1)-dimensional Painlevé integrable equation.

5.
Heliyon ; 10(9): e30548, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38765162

RESUMO

Urban expansion often occurs at the expense of cropland loss, posing challenges to sustainable urban growth and food security. However, detailed investigations into urban expansion and cropland loss remain limited, particularly in regions with varying levels of urbanization. Here, we take Guangdong Province, China, as a case study to exemplify how urban expansion affects cropland using remotely sensed land use products. We adopted geospatial analysis, correlation indicators, and landscape metrics to uncover their spatial relationships at 10-m spatial resolutions. Results showed that urban areas increased by 6335 km2 while cropland decreased by 3780 km2 from 2017 to 2022. Notably, 41 % of newly expanded urban areas were from croplands, and 45 % of lost croplands were converted to urban areas. Western Guangdong experienced the largest extent of urban expansion and cropland loss, emerging as a hotspot region in recent years. Additionally, our analysis observed the increasing compactness of urban areas and the growing fragmentation of cropland landscapes over time. These findings shed light on the intricate dynamics between urban expansion and cropland loss in rapidly urbanizing regions, which provide valuable insights for sustainable urban development, agricultural practice, and land management in the future.

6.
Front Immunol ; 15: 1404121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720900

RESUMO

Pharmacodynamic assessment of T-cell-based cancer immunotherapies often focus on detecting rare circulating T-cell populations. The therapy-induced immune cells in blood-derived clinical samples are often present in very low frequencies and with the currently available T-cell analytical assays, amplification of the cells of interest prior to analysis is often required. Current approaches aiming to enrich antigen-specific T cells from human Peripheral Blood Mononuclear Cells (PBMCs) depend on in vitro culturing in presence of their cognate peptides and cytokines. In the present work, we improved a standard, publicly available protocol for T-cell immune analyses based on the in vitro expansion of T cells. We used PBMCs from healthy subjects and well-described viral antigens as a model system for optimizing the experimental procedures and conditions. Using the standard protocol, we first demonstrated significant enrichment of antigen-specific T cells, even when their starting frequency ex vivo was low. Importantly, this amplification occurred with high specificity, with no or neglectable enrichment of irrelevant T-cell clones being observed in the cultures. Testing of modified culturing timelines suggested that the protocol can be adjusted accordingly to allow for greater cell yield with strong preservation of the functionality of antigen-specific T cells. Overall, our work has led to the refinement of a standard protocol for in vitro stimulation of antigen-specific T cells and highlighted its reliability and reproducibility. We envision that the optimized protocol could be applied for longitudinal monitoring of rare blood-circulating T cells in scenarios with limited sample material.


Assuntos
Linfócitos T , Humanos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Antígenos Virais/imunologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Células Cultivadas , Vacinas Anticâncer/imunologia
7.
Sci Bull (Beijing) ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38724302

RESUMO

Expanding the network of connected and resilient protected areas (PAs) for climate change adaptation can help species track suitable climate conditions and safeguard biodiversity. This is often overlooked when expanding PAs and quantifying their benefits, resulting in an underestimate of the benefits of expanding PAs. We expanded PAs through terrestrial mammalian species distribution hotspots, Key Biodiversity Areas (KBAs), and wilderness areas. Then, we constructed climate connectivity networks using a resistance-based approach and further quantified the network resilience to propose resilient climate response strategies in China. The results showed that existing PAs suffered from location biases with important biodiversity areas. The existing PAs represented about half of the KBAs and wilderness areas, yet only 12.08% of terrestrial mammalian species distribution hotspots were located within existing PAs. Compared with the existing PA network, the network efficiency and resilience of the expanded PAs' climate connectivity increased to 1.80 times and 1.78 times, respectively. With 56% of the nodes remaining, the network efficiency of the expanded PAs was equivalent to that of the existing PAs with all nodes. The network resilience of preferentially protecting and restoring low human footprint patches was approximately 1.5-2 times that of the random scenario. These findings highlighted that confronted with the unoptimistic situation of global warming, nature conservation based on existing PAs was no longer optimal. It was critical to construct a connected and resilient conservation network relying on both important biodiversity areas and low human footprint patches.

8.
Heliyon ; 10(9): e29911, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707428

RESUMO

Introduction: Unilateral pulmonary edema (UPE), a life-threatening complication of cardiac surgery, often occurs after prolonged cardiopulmonary bypass and lung collapse, especially in minimally-invasive cardiac surgery (MICS). The present study reported a young patient with severe UPE after the surgery as well as corresponding clinical treatments. In addition to the supportive treatment of extracorporeal membrane oxygenation (ECMO), monitoring changes in cardiopulmonary function and early clinical interventions are crucial. Conclusion: By weighing the beneficial and detrimental effects of the treatment, it calls for early diagnosis and new therapeutic strategies for the complication.

9.
Contemp Clin Dent ; 15(1): 27-34, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707668

RESUMO

Background: Four different designs of mini-implant-assisted rapid palatal expansion (MARPE) and protraction in nasomaxillary complex and mid-palatal sutures in late adolescent skeletal Class III malocclusion were compared using a three-dimensional finite element analysis. Methods: A finite element model of skull and related sutures was constructed using the computed tomography scan of a 16-year-old female patient with skeletal Class III and ANB of -2°. Four appliance designs: Type I: MARPE with palatal force, Type II: MARPE with buccal force, Type III: Hybrid hyrax with palatal force, and Type IV: Hybrid hyrax with buccal force. Protraction vectors were and analyzed using Ansys software (ANSYS 2021 R2). The displacement pattern of the nasomaxillary structures and the stress distribution in the sutures were examined in all four appliance designs. Results: All the appliance designs resulted in a forward movement of the maxilla, while Type I and III, which used palatal protraction force, caused the greatest forward displacement. In Type I, II, and III, along with forward movement, a clockwise rotation of maxilla was observed, while in Type IV, an anticlockwise rotation of maxilla was observed. Type I, II, and III resulted in higher stress distribution around the superior structures, while Type IV resulted in less stress distribution around the superior structures of maxilla. Conclusion: The forward displacement was enhanced when palatal plates were used to protract the maxilla. The effective appliance design for skeletal class III with open bite case was Type I, II, and III and Type IV for deep bite cases.

10.
Arch Pharm (Weinheim) ; : e2400171, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710636

RESUMO

This study presents an exploration of the chemical space around derivatives of 3-benzamidopyrazine-2-carboxamides, previously identified as potent antimycobacterial compounds with predicted binding to mycobacterial prolyl-transfer RNA synthetase. New urea derivatives (Series-1) were generally inactive, probably due to their preference for cis-trans conformation (confirmed by density functional theory calculations and experimentally by nuclear overhauser effect spectroscopy NMR). Series-2 (3-benzamidopyrazine-2-carboxamides with disubstituted benzene ring) demonstrated that substituents larger than fluorine are not tolerated in the ortho position of the benzene ring. This series brought two new compounds (21: R = 2-F, 4-Cl and 22: R = 2-F, 4-Br) with in vitro activity against Mycobacterium tuberculosis H37Rv as well as multidrug-resistant clinical isolates, with minimum inhibitory concentration ranging from 6.25 to 25 µg/mL. The lactone-type derivatives 4H-pyrazino[2,3-d][1,3]oxazin-4-ones (Series-3) were inactive, but solvent stability studies of compound 29 indicated that they might be developed to usable lactone prodrugs of inhibitors of mycobacterial aspartate decarboxylase (PanD).

11.
BMC Neurol ; 24(1): 154, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714961

RESUMO

BACKGROUND: Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder caused by CGG repeat expansion of FMR1 gene. Both FXTAS and neuronal intranuclear inclusion disease (NIID) belong to polyglycine diseases and present similar clinical, radiological, and pathological features, making it difficult to distinguish these diseases. Reversible encephalitis-like attacks are often observed in NIID. It is unclear whether they are presented in FXTAS and can be used for differential diagnosis of NIID and FXTAS. CASE PRESENTATION: A 63-year-old Chinese male with late-onset gait disturbance, cognitive decline, and reversible attacks of fever, consciousness impairment, dizziness, vomiting, and urinary incontinence underwent neurological assessment and examinations, including laboratory tests, electroencephalogram test, imaging, skin biopsy, and genetic test. Brain MRI showed T2 hyperintensities in middle cerebellar peduncle and cerebrum, in addition to cerebellar atrophy and DWI hyperintensities along the corticomedullary junction. Lesions in the brainstem were observed. Skin biopsy showed p62-positive intranuclear inclusions. The possibilities of hypoglycemia, lactic acidosis, epileptic seizures, and cerebrovascular attacks were excluded. Genetic analysis revealed CGG repeat expansion in FMR1 gene, and the number of repeats was 111. The patient was finally diagnosed as FXTAS. He received supportive treatment as well as symptomatic treatment during hospitalization. His encephalitic symptoms were completely relieved within one week. CONCLUSIONS: This is a detailed report of a case of FXTAS with reversible encephalitis-like episodes. This report provides new information for the possible and rare features of FXTAS, highlighting that encephalitis-like episodes are common in polyglycine diseases and unable to be used for differential diagnosis.


Assuntos
Ataxia , Encefalite , Síndrome do Cromossomo X Frágil , Tremor , Humanos , Masculino , Pessoa de Meia-Idade , Tremor/diagnóstico , Tremor/genética , Tremor/etiologia , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/diagnóstico , Síndrome do Cromossomo X Frágil/complicações , Ataxia/diagnóstico , Ataxia/genética , Encefalite/diagnóstico , Encefalite/complicações , Encefalite/genética , Encefalite/patologia , Proteína do X Frágil da Deficiência Intelectual/genética , Diagnóstico Diferencial , Corpos de Inclusão Intranuclear/patologia , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/complicações
12.
Adv Mater ; : e2312343, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691579

RESUMO

Seawater batteries that directly utilize natural seawater as electrolytes are ideal sustainable aqueous devices with high safety, exceedingly low cost, and environmental friendliness. However, the present seawater batteries are either primary batteries or rechargeable half-seawater/half-nonaqueous batteries because of the lack of suitable anode working in seawater. Here, a unique lattice engineering to unlock the electrochemically inert anatase TiO2 anode to be highly active for the reversible uptake of multiple cations (Na+, Mg2+, and Ca2+) in aqueous electrolytes is demonstrated. Density functional theory calculations further reveal the origin of the unprecedented charge storage behaviors, which can be attributed to the significant reduction of the cations diffusion barrier within the lattice, i.e., from 1.5 to 0.4 eV. As a result, the capacities of anatase TiO2 with 2.4% lattice expansion are ≈100 times higher than the routine one in natural seawater, and ≈200 times higher in aqueous Na+ electrolyte. The finding will significantly advance aqueous seawater energy storage devices closer to practical applications.

13.
SAGE Open Med Case Rep ; 12: 2050313X241249081, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711679

RESUMO

Re-expansion pulmonary edema is defined as pulmonary edema that occurs when a chronically collapsed lung rapidly re-expands, most commonly following chest tube placement for pneumothorax, re-expansion of severe atelectasis, and evacuation of pleural effusion. Though it is very rare, the sudden onset and clinical features of re-expansion pulmonary edema make it a lethal complication that requires urgent treatment. We present a 60-year-old patient who underwent an aortic valve replacement with pre-existing large bilateral pleural effusions. Intraoperatively, upon evacuation of the pleural effusions, the patient developed worsening lung compliance, refractory hypoxemia, and hypercapnia that required emergent veno-venous extracorporeal membrane oxygenation support.

14.
Chem Asian J ; : e202400408, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715237

RESUMO

The thermal transformation of zircon to scheelite in BiVO4 was studied by in-situ Synchrotron X-ray diffraction and TGA/FTIR analysis. Upon heating, the tetragonal zircon polymorph of BiVO4 (tz-BiVO4) transitioned to the tetragonal scheelite (ts-)polymorph between 693-773 K, then to monoclinic fergusonite (mf) polymorph upon cooling. An anomaly in thermal expansion was observed between 400-500 K, associated with loss of H2O/NH4+. Heating tz-BiVO4 resulted in contraction of the V-O bond distance and VO4 polyhedra volume due to rotation of the VO4. Attempts to study this by neutron diffraction failed due to the large incoherent scatter from the hydrogenous species. Efforts to remove these species while maintaining the tz-BiVO4 structure were unsuccessful, suggesting they play a role in stabilizing the zircon polymorph. The local structure of both mf-BiVO4 and tz-BiVO4 were investigated by X-ray Pair Distribution Function analysis.

15.
Eur J Mass Spectrom (Chichester) ; : 14690667241251792, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38706254

RESUMO

This paper proposed a dual-layer linear ion trap mass analyzer (dLIT) based on micro-electromechanical systems (MEMS) technology and stacked-layer structure for the development of MEMS mass spectrometry. Its basic performance and potential capabilities were explored by ion trajectory simulations. The theoretical formulas were modified by implementing multipole expansion. The simulation results were confirmed to be highly consistent with theoretical calculations in multiple aspects, including stability diagram, secular frequencies, and mass linearity, with only a deviation of 1-2%. In the boundary ejection mode, close to 100% ejection was achieved in a single dimension by applying extra quadrupole DC voltage. Preliminary simulation results showed that dLIT can achieve a peak width of ∼2 mass units (full width at half maximum, FWHM) for m/z 60 ions even at pressures as high as 50 Pa. Furthermore, the application of AC frequency scanning mode in dLIT was also evaluated, and preliminary simulation results yield a peak width of 0.3-0.4 mass units (FWHM). The dLIT offered several advantages, including high-precision fabrication at the sub-millimeter scale, excellent high-pressure performance, and a clear physical model. It preliminarily proved to be an ideal mass analyzer for MEMS mass spectrometry.

16.
Mol Neurobiol ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709391

RESUMO

The unclear pathogenic mechanisms of neurodegenerative disorders stemming from NOTCH2NLC GGC repeat expansions drive focused research. Thus, a bibliometric and meta-analysis was conducted to uncover research trends and positivity rates in NOTCH2NLC. We conducted systematic searches in the Web of Science, PubMed, Embase, and Scopus databases for studies related to NOTCH2NLC up until August 2, 2023. Information regarding countries, institutions, authors, journals, and keywords of studies included in the Web of Science was analyzed and visualized. The positivity rates of NOTCH2NLC GGC repeat expansions across all screened patients and patients' families were pooled under the random-effects model. Publication bias and its impact were examined using funnel plots, Egger's linear regression, and trim-and-fill method. The bibliometric analysis, revealing pronounced publication growth, comprised 119 studies, which came from China and Japan particularly. "Neuronal intranuclear inclusion disease" emerged as a frequently used keyword. The meta-analysis comprised 36 studies, indicating global positivity rates of 1.79% (95% CI, 0.75-3.17) for all patients and 2.00% (95% CI, 0.26-4.78) for patients' families. Subgroup analyses based on region and phenotype suggested the highest NOTCH2NLC positivity rates in Taiwan population (5.42%, 95% CI 0.08-16.89) and in leukoencephalopathy-dominant patients (8.25%, 95% CI, 3.01-15.60). Sensitivity analysis affirmed the robustness of results. In conclusion, NOTCH2NLC GGC repeat expansions exhibit rare globally, primarily in East Asia, and leukoencephalopathy-dominant patients, emphasizing regional and phenotypic distinctions. Emerging focal points in NOTCH2NLC researches underscore the need for collaborative exploration.

17.
Oral Maxillofac Surg ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709398

RESUMO

OBJECTIVE: This retrospective study aims to assess the three-dimensional dentoskeletal effects and median palatal suture opening pattern in patients undergoing modified surgically assisted maxillary rapid expansion (SARME) without pterygoid plate detachment. METHODS: Twenty-eight patients submitted to modified SARME between 2009 and 2016 were retrospectively evaluated through cone-beam computed tomography (CBCT). Dental and skeletal measurements were taken at three different operative periods (before the expansion - T0; at the end of the activation of the Hyrax device - T1; and six months after the immobilization of the device - T2). Statistical analyses, including ANOVA and Pearson's correlation coefficient, were performed using SPSS software. RESULTS: SARME demonstrated significant transverse maxillary expansion (with an average of 6.05 mm) with a greater impact in the anterior region. Dental measurements, including canine and molar distances, exhibited significant changes over the operative periods. Bone measurements (ANS and PNS) presented small but significant alterations, including a slight inferior displacement of ANS during device activation. The nasal floor width increased, followed by a width reduction after immobilization. The median palatal suture predominantly exhibited a Type II (V-shaped) opening. CONCLUSION: The modified SARME presented a transversal direction increase and a super-lower skeletal displacement, with the anterior region being more affected than the posterior region. There was no change in the anteroposterior direction of the maxilla. Additionally, there was an increase in the linear dental measurements and a decrease in the angular measurement, with a positive correlation between the amount of posterior bone expansion and molar expansion as a result of the treatment in the analyzed period.

18.
Sci Rep ; 14(1): 10236, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702376

RESUMO

This research focuses on utilizing non-uniform magnetic fields, induced by dipoles, to control and enhance thermal energy transfer in a two-dimensional cooling conduit including a double backward-facing step. The presence of electronic equipment along the straight channel path creates such arrangements, and cooling is often ineffective in the corners of the formed steps. The use of a non-constant magnetic field is a passive technique to improve the cooling rate in these sections without changing the internal geometry, thereby increasing the heat transfer rate. A commercial software based on the finite volume technique is employed to solve the governing equations of fluid flow and heat transfer. Multiple parameters are examined in this study, including the flow Reynolds number (12.5-50), dipole location and strength (0.1-5 A-m), and the number of dipoles (single or double). The results indicate that all of these parameters have a significant impact on the thermal energy transfer. The results of the study show that a single dipole increase the average heat transfer by about 22%, two magnetic fields by 40%, the strength of the magnetic source by 24% with respect to the non-magnetic field in the present study.

19.
J World Fed Orthod ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38697910

RESUMO

Posterior Crossbite is a common condition resulting because of transverse maxillary deficiency. The growth of the craniofacial complex finishes first in the transverse dimension, followed by sagittal and vertical dimensions. Conventional rapid palatal expansion (RPE) appliances are commonly used to correct transverse maxillary deficiency. Although RPE is efficient in correcting posterior crossbite, it results in dental side effects such as buccal tipping of maxillary molars, root resorption, bone dehiscence, and relapse. Mini-implant-assisted RPE has been introduced to increase the skeletal effects of expansion especially in patients with increased maturation and greater interdigitation of midpalatal suture. This article will review the biomechanics of RPE and mini-implant-assisted RPE. Additionally, the different designs of MARPE and the long-term clinical effects of expansion appliances will also be discussed in detail.

20.
Materials (Basel) ; 17(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38730765

RESUMO

The plastic deformation of TWIP steel is greatly inhibited during the expansion process. The stress-strain curves obtained through expansion experiments and observations of fracture morphology confirmed the low plastic behavior of TWIP steel during expansion deformation. Through an analysis of the mechanical expansion model, it was found that the expansion process has a lower stress coefficient and a faster strain rate than stretching, which inhibits the plasticity of TWIP steel during expansion deformation. Using metallographic microscopy, transmission electron microscopy, and EBSD to observe the twin morphology during expansion deformation and tensile deformation, it was found that expansion deformation has a higher twin density, which is manifested in a denser twin arrangement and a large number of twin deliveries in the microscopic morphology. During the expansion deformation process, dislocation slips are hindered by twins, the free path of the slips is reduced, and dislocations accumulate significantly. The accumulation area is the initial point of crack expansion. The results show that the significant dislocation accumulation caused by the delivery of a large number of twins under expansion deformation is the main reason for the decrease in the plasticity of TWIP steel.

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