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1.
Cell Mol Biol (Noisy-le-grand) ; 70(2): 285-290, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38431838

RESUMO

Cerebral aneurysm can rupture a blood vessel and cause bleeding in the brain. Microsurgical clipping of the tumor neck has been reported to be effective in treating cerebral aneurysm rupture and bleeding. This research attempted to clarify the clinical efficacy of early microsurgical clipping of tumor neck for treating cerebral aneurysm rupture and bleeding, and its impact on the prognosis of patients. One hundred patients with cerebral aneurysm rupture and bleeding patients were treated. They were selected and divided into experimental group (n=25) and control group (n=25) according to surgical time. All patients underwent microsurgical clipping of tumor neck for therapy. The control group chose to undergo surgery 72 hours after the onset of cerebral aneurysm rupture and bleeding, while the experimental group chose to undergo complete surgery within 72 hours after the onset of cerebral aneurysm rupture and bleeding. Primary outcome measures were incidence of complications, cognitive function scores, prognosis, surgical indicators, oxidative stress response and quality of life. Results showed that compared to the control group, the incidence of complications in experimental group exhibited depletion (P<0.05), the prognosis in experimental group exhibited elevation (P<0.05), the hospitalization time in experimental group exhibited depletion (P<0.05), the nomination, abstraction, language, orientation, attention, delayed recall and visual and executive function scores and total scores in experimental group exhibited elevation (P<0.05), serum levels of oxidative stress-related indicators in experimental group exhibited depletion (P<0.05) and the quality of life in experimental group exhibited elevation (P<0.05). In conclusion, early microsurgical clipping of the tumor neck can reduce the risk of complications and cognitive impairment in patients with cerebral aneurysm rupture and bleeding.


Assuntos
Neoplasias de Cabeça e Pescoço , Aneurisma Intracraniano , Acidente Vascular Cerebral , Humanos , Aneurisma Intracraniano/cirurgia , Qualidade de Vida , Resultado do Tratamento , Hemorragia
2.
Brain Behav ; 14(3): e3465, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38468469

RESUMO

BACKGROUND: SP gene family, consisting of SP100, SP110, SP140, and SP140L, has been implicated in the initiation and advancement of numerous malignancies. Nevertheless, their clinical significance in glioma remains incompletely understood. METHOD: Expression levels and prognostic significance of SP family members were evaluated in the TCGA and CGGA datasets. Multifactorial analysis was used to identify SP gene family members that can independently impact the prognosis of glioma patients. A SP140-based predictive risk model/nomogram was developed in TCGA dataset and validated in CGGA dataset. The model's performance was evaluated through receiver operating characteristic (ROC) curves, calibration plots, and decision curve analyses. Phenotypic associations of SP140 and TRIM22 were examined through CancerSEA and TIMER. The effect of SP140 inhibitor in glioma progress and TRIM22/PI3K/AKT signaling pathway was confirmed in U251/U87 glioma cells. RESULTS: The SP family members exhibited elevated expression in gliomas and were negatively correlated with prognosis. SP140 emerged as an independent prognostic factor, and a SP140-based nomogram/predictive risk model demonstrated high accuracy. SP140 inhibitor, GSK761, lead to the suppression of TRIM22 expression and the PI3K/AKT signaling pathway. GSK761 also restrain glioma proliferation, migration, and invasion. Furthermore, SP140 and TRIM22 coexpressed in glioma cells with high level of vascular proliferation, TRIM22 is closely associated with the immune cell infiltration. CONCLUSION: SP140-based nomogram proved to be a practical tool for predicting the survival of glioma patients. SP140 inhibitor could suppress glioma progress via TRIM22/PI3K/AKT signaling pathway.


Assuntos
Glioma , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proliferação de Células , Transdução de Sinais , Glioma/tratamento farmacológico , Glioma/genética , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/farmacologia , Proteínas Repressoras/metabolismo , Antígenos de Histocompatibilidade Menor/farmacologia , Fatores de Transcrição , Antígenos Nucleares/metabolismo , Antígenos Nucleares/farmacologia
3.
Phys Rev Lett ; 132(5): 056101, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38364152

RESUMO

The slow transition from an out-of-equilibrium glass towards a supercooled liquid is a complex relaxation phenomenon. In this Letter, we study the correlation between mechanical relaxation and equilibration kinetics in a Pd_{20}Pt_{20}Cu_{20}Ni_{20}P_{20} high-entropy metallic glass. The evolution of stress relaxation with aging time was obtained with an unprecedented detail, allowing us to pinpoint new interesting features. The long structural relaxation towards equilibrium contains a wide distribution of activation energies, instead of being just associated to the ß relaxation as commonly accepted. The stress relaxation time can be correlated with the equilibration rate and we observe a decrease of microstructural heterogeneity which contrasts with an increase of dynamic heterogeneity. These results significantly enhance our insight of the interplay between relaxation dynamics and thermodynamics in metallic glasses.

4.
Nanomicro Lett ; 16(1): 108, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315294

RESUMO

Hydrogen production through hydrogen evolution reaction (HER) offers a promising solution to combat climate change by replacing fossil fuels with clean energy sources. However, the widespread adoption of efficient electrocatalysts, such as platinum (Pt), has been hindered by their high cost. In this study, we developed an easy-to-implement method to create ultrathin Pt nanomembranes, which catalyze HER at a cost significantly lower than commercial Pt/C and comparable to non-noble metal electrocatalysts. These Pt nanomembranes consist of highly distorted Pt nanocrystals and exhibit a heterogeneous elastic strain field, a characteristic rarely seen in conventional crystals. This unique feature results in significantly higher electrocatalytic efficiency than various forms of Pt electrocatalysts, including Pt/C, Pt foils, and numerous Pt single-atom or single-cluster catalysts. Our research offers a promising approach to develop highly efficient and cost-effective low-dimensional electrocatalysts for sustainable hydrogen production, potentially addressing the challenges posed by the climate crisis.

5.
J Phys Chem Lett ; 15(3): 811-816, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38232179

RESUMO

Establishing a robust quantitative correlation between thermodynamics and dynamics in amorphous matter remains a significant challenge in condensed matter physics. Although the classical Adam-Gibbs relationship represents a pivotal step in this direction and the correlation between relaxation time and configurational entropy has been partially verified in simple liquids, this quantitative link has yet to be tested in realistic glass-forming systems where complex many-body interactions are present. Here we conduct free energy samplings and lattice dynamics analysis to distinguish vibrational entropy from configurational entropy in a realistic Cu-Zr model of a metallic glass. Our calculations unveil a power-law relationship (with a substantial exponent of ∼3) between the logarithmic relaxation time and configurational entropy, surpassing the linear prediction of the original Adam-Gibbs relationship. This nonlinear entropy driven relaxation time variation likely originates from anisotropic nature of atomic many-body interactions, suggesting that factors beyond thermodynamics contribute to the glass transition phenomenon.

6.
Free Radic Biol Med ; 213: 394-408, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38281626

RESUMO

BACKGROUND: The mitochondrial unfolded protein response (UPRmt) is a vital biological process that regulates mitochondrial protein homeostasis and enables glioblastoma cells to cope with mitochondrial oxidative stress in the tumor microenvironment. We previously reported that the binding of mitochondrial stress-70 protein (mtHSP70) to GrpE protein homolog 1 (GrpEL1) is involved in the regulation of the UPRmt. However, the mechanisms regulating their binding remain unclear. Herein, we examined the UPRmt in glioblastoma and explored whether modulating the interaction between mtHSP70 and GrpEL1 affects the UPRmt. METHODS: Western blot analysis, aggresome staining, and transmission electron microscopy were used to detect the activation of the UPRmt and protein aggregates within mitochondria. Molecular dynamics simulations were performed to investigate the impact of different mutations in mtHSP70 on its binding to GrpEL1. Endogenous site-specific mutations were introduced into mtHSP70 in glioblastoma cells using CRISPR/Cas9. In vitro and in vivo experiments were conducted to assess mitochondrial function and glioblastoma progression. RESULTS: The UPRmt was activated in glioblastoma cells in response to oxidative stress. mtHSP70 regulated mitochondrial protein homeostasis by facilitating UPRmt-progress protein import into the mitochondria. Acetylation of mtHSP70 at Lys595/653 enhanced its binding to GrpEL1. Missense mutations at Lys595/653 increased mitochondrial protein aggregates and inhibited glioblastoma progression in vitro and in vivo. CONCLUSIONS: We identified an innovative mechanism in glioblastoma progression by which acetylation of mtHSP70 at Lys595/653 influences its interaction with GrpEL1 to regulate the UPRmt. Mutations at Lys595/653 in mtHSP70 could potentially serve as therapeutic targets and prognostic indicators of glioblastoma.


Assuntos
Glioblastoma , Proteínas de Choque Térmico HSP70 , Humanos , Proteínas de Choque Térmico HSP70/metabolismo , Acetilação , Glioblastoma/genética , Glioblastoma/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Microambiente Tumoral
7.
Nat Commun ; 15(1): 768, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38278829

RESUMO

Handheld robots offer accessible solutions with a short learning curve to enhance operator capabilities. However, their controllable degree-of-freedoms are limited due to scarce space for actuators. Inspired by muscle movements stimulated by nerves, we report a handheld time-share driven robot. It comprises several motion modules, all powered by a single motor. Shape memory alloy (SMA) wires, acting as "nerves", connect to motion modules, enabling the selection of the activated module. The robot contains a 202-gram motor base and a 0.8 cm diameter manipulator comprised of sequentially linked bending modules (BM). The manipulator can be tailored in length and integrated with various instruments in situ, facilitating non-invasive access and high-dexterous operation at remote surgical sites. The applicability was demonstrated in clinical scenarios, where a surgeon held the robot to conduct transluminal experiments on a human stomach model and an ex vivo porcine stomach. The time-share driven mechanism offers a pragmatic approach to build a multi-degree-of-freedom robot for broader applications.


Assuntos
Robótica , Suínos , Animais , Humanos , Movimento (Física)
8.
Nano Lett ; 23(23): 11288-11296, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37983011

RESUMO

Core-shell crystalline-amorphous nanocomposites, featuring nanograins surrounded by thick amorphous boundaries, are promising nanoarchitectures for achieving exceptional strength through cooperative strengthening effects. However, a comprehensive understanding of the influence of characteristic sizes, particularly the amorphous thickness, on codeformation strengthening is still lacking, limiting the attainment of the strength limit. Here, we employ molecular dynamics simulations to investigate Cu-CuTa crystalline-amorphous nanocomposites with varying grain sizes and amorphous thicknesses. Our findings demonstrate significant strengthening effects in nanocomposites, effectively suppressing the Hall-Petch breakdown observed in traditional amorphous-free nanograined Cu. Intriguingly, we observe a maximum strength followed by a strengthening-softening transition dependent on the amorphous thickness, as exemplified by a representative nanocomposite featuring a 12.5 nm grain size and a critical amorphous thickness of 4 nm. Inspired by observed shifts in atomistic mechanisms, we developed a theoretical model encompassing variations in grain size and amorphous thickness, providing valuable insights into the size-strength relationship for crystalline-amorphous nanocomposites.

9.
Front Neurol ; 14: 1123108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006487

RESUMO

Background: Spontaneous epidural hematoma (EDH) has been suggested to be associated with adjacent infective pathologies, dural vascular malformations, extradural metastases, or coagulopathies. Cryptogenic spontaneous EDH is extremely rare. Case presentation: The present study reports the case of a cryptogenic spontaneous EDH in a young woman following sexual intercourse. She was diagnosed with consecutive EDH at three different sites within a short time. After three timely operations, a satisfactory outcome was achieved. Conclusion: EDH should be investigated when a young patient develops headaches and shows signs of increased ICP after emotional hyperactivity or hyperventilation. If early diagnosis and surgical decompression can be carried out in time, the prognosis would be satisfactory.

10.
Naunyn Schmiedebergs Arch Pharmacol ; 396(3): 441-451, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36445384

RESUMO

Tamsulosin is a therapeutic drug of alpha-adrenergic antagonists. Previous randomized controlled trials and retrospective analyses have proved the efficacy of tamsulosin on many urinary system diseases. However, there is still a conflict about whether tamsulosin could prevent postoperative urinary retention (POUR). This meta-analysis aims to probe into the efficacy of tamsulosin for preventing POUR versus placebo. We searched MEDLINE, EMBASE, and Cochrane Library from December 31, 1999 to April 30, 2022, for randomized controlled trials (RCTs). Studies that were not RCTs or without negative controls were excluded. Cochrane Collaboration harmonized criteria were used to assess the risk of bias in included studies. Revman (version 5.3) software was invited to synthesize the results. We performed subgroup analyses to explore the factors that could influence tamsulosin's efficacy in POUR prevention. Our meta-analysis pooled 13 RCTs with 2163 patients. We concluded that tamsulosin brought about a significant reduction in the risk of POUR versus placebo (13.54% vs 20.88% for tamsulosin vs placebo, RR = 0.63, 95% CI 0.47 to 0.84, P = 0.002). Tamsulosin could significantly reduce the risk of POUR in abdominal (11.52% vs 20.25% for tamsulosin vs placebo, RR = 0.52, 95% CI 0.31 to 0.88, P = 0.02) and female pelvic surgery (15.57% vs 31.50% for tamsulosin vs placebo, RR = 0.51, 95% CI 0.31 to 0.82, P = 0.006) but not in spinal surgery (13.45% vs 12.75% for tamsulosin vs placebo, RR = 1.07, 95% CI 0.72 to 1.60, P = 0.73) and lower limb surgery (21.43% vs 33.33% for tamsulosin vs placebo, RR = 0.64, 95% CI 0.35 to 1.14, P = 0.13). The preventive effect of postoperative (17.70% vs 33.93% for tamsulosin vs placebo, RR = 0.53, 95% CI 0.33 to 0.85, P = 0.008) and postoperative with preoperative tamsulosin (13.96% vs 23.44% for tamsulosin vs placebo, RR = 0.64, 95% CI 0.43 to 0.93, P = 0.02) on POUR were significantly better than preoperative management (11.95% vs 14.63% for tamsulosin vs placebo, RR = 0.62, 95% CI 0.23 to 1.65, P = 0.34). Postoperative catheter placement appears to have a negative impact on the POUR-preventive effect of tamsulosin. (9.37% vs 16.46% for tamsulosin vs placebo, RR = 0.51, 95% CI 0.31 to 0.83, P = 0.007) Tamsulosin showed significantly effect on POUR prevention in patients during spinal (15.07% vs 26.51% for tamsulosin vs placebo, RR = 0.52, 95% CI 0.31 to 0.90, P = 0.02) and epidural anesthesia (12.50% vs 29.79% for tamsulosin vs placebo, RR = 0.42, 95% CI 0.18 to 1.00, P = 0.05) but not in general anesthesia (12.40% vs 18.52% for tamsulosin vs placebo, RR = 0.68, 95% CI 0.45 to 1.03, P = 0.07). Tamsulosin shows better outcomes for preventing POUR than placebo. Besides, tamsulosin showed a different effect on POUR prevention in the various surgical sites, anesthesia, medication management, and catheter use. However, our conclusions still have some limitations due to the lack of evidence.


Assuntos
Anestesia , Retenção Urinária , Feminino , Humanos , Tansulosina/uso terapêutico , Retenção Urinária/tratamento farmacológico , Retenção Urinária/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Complicações Pós-Operatórias/prevenção & controle
11.
Phys Rev Lett ; 129(17): 175501, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36332263

RESUMO

Lacking the structural information of crystalline solids, the origin of the relaxation dynamics of metallic glasses is unclear. Here, we report the evolution of stress relaxation of high-entropy metallic glasses with distinct ß relaxation behavior. The fraction of liquidlike zones, determined at each temperature by the intensity of stress decay, is shown to be directly related to both the aging process and the spectrum of relaxation modes obtained by mechanical spectroscopy. The results shed light on the intrinsic correlation between the static and dynamic mechanical response in high-entropy and conventional metallic glasses, pointing toward a sluggish diffusion high-entropy effect in the liquid dynamics.

12.
Front Neurol ; 13: 964627, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110393

RESUMO

Background: Intermittent theta-burst stimulation (iTBS) is an optimized rTMS modality that could modulate the excitability of neural structures. Several studies have been conducted to investigate the efficacy of iTBS in improving the motor function of stroke patients. However, the specific role of iTBS in motor function recovery after stroke is unclear. Hence, in our study, we performed a meta-analysis to investigate the efficacy of iTBS for the motor function improvement of stroke patients. Methods: MEDLINE, Embase, and Cochrane Library were searched until May 2022 for randomized controlled trials (RCTs). Results: Thirteen RCTs with 334 patients were finally included in our study. The primary endpoints were the Fugl-Meyer assessment scale (FMA) and Motor Assessment Scale (MAS) change from baseline. We found that iTBS led to a significant reduction in FMA score (P = 0.002) but not in MAS score (P = 0.24) compared with the sham group. Moreover, standard 600-pulse stimulation showed a better effect on motor function improvement than the sham group (P = 0.004), however, 1200-pulse iTBS showed no effect on motor function improvement after stroke (P = 0.23). The effect of iTBS for improving motor function only exists in chronic stroke patients (P = 0.02) but not in subacute patients (P = 0.27). Conclusion: This study supports that iTBS has good efficacy for improving motor function in stroke patients. Therefore, standard 600-pulse stimulation iTBS therapy is proper management and treatment for chronic stroke.

13.
Open Life Sci ; 16(1): 1175-1181, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34761108

RESUMO

Glioma is a type of common intracranial tumor. In this study, we investigated the molecular mechanism by which miR-378a-3p regulates cisplatin (CDDP) chemosensitivity in glioma cells via insulin-like growth factor 1 receptor (IGF1R). U251/CDDP cells were treated with CDDP and transfected with miR-378a-3p mimics, NC mimics, or pcDNA-IGF1R. qRT-PCR was used to measure the differential level of miR-378a-3p. CCK-8 assay was used to test cell proliferation, and flow cytometry was used to analyze apoptosis. The targeting relationship between miR-378a-3p and IGF1R was tested through a dual-luciferase reporter gene assay. In contrast to normal glial cells, the miR-378a-3p level decreased in human glioma U251 cells and had lower expression in U251/CDDP cells. Compared with the CDDP group, miR-378a-3p significantly caused the inhibition of U251/CDDP cell proliferation and enhanced apoptosis in the miR-378a-3p mimics + CDDP group. Another experiment confirmed that IGF1R was a target gene of miR-378a-3p, and overexpression of miR-378a-3p inhibited IGF1R expression. In addition, co-overexpression of miR-378a-3p and IGF1R induced the upregulation of the U251/CDDP cell proliferation and the inhibition of apoptosis in the miR-378a-3p mimics + pcDNA-IGF1R + CDDP group. This study confirmed that miR-378a-3p promoted the sensitivity of glioma cells to CDDP in glioma patients via targeting IGF1R to increase the therapeutic effect during chemotherapy.

14.
Sci Adv ; 5(11): eaax7256, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31803833

RESUMO

Design of bulk metallic glasses (BMGs) with excellent properties has been a long-sought goal in materials science and engineering. The grand challenge has been scaling up the size and improving the properties of metallic glasses of technological importance. In this work, we demonstrate a facile, flexible route to synthesize BMGs and metallic glass-glass composites out of metallic-glass ribbons. By fully activating atomic-scale stress relaxation within an ultrathin surface layer under ultrasonic vibrations, we accelerate the formation of atomic bonding between ribbons at a temperature far below the glass transition point. In principle, our approach overcomes the size and compositional limitations facing traditional methods, leading to the rapid bonding of metallic glasses of distinct physical properties without causing crystallization. The outcome of our current research opens up a window not only to synthesize BMGs of extended compositions, but also toward the discovery of multifunctional glass-glass composites, which have never been reported before.

15.
Hum Hered ; 84(1): 1-8, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31461710

RESUMO

Quantum-inspired genetic algorithms (QGAs) were recently introduced for the prediction of RNA secondary structures, and they showed some superiority over the existing popular strategies. In this paper, for RNA secondary structure prediction, we introduce a new QGA named multi-population assisted quantum genetic algorithm (MAQGA). In contrast to the existing QGAs, our strategy involves multi-populations which evolve together in a cooperative way in each iteration, and the genetic exchange between various populations is performed by an operator transfer operation. The numerical results show that the performances of existing genetic algorithms (evolutionary algorithms [EAs]), including traditional EAs and QGAs, can be significantly improved by using our approach. Moreover, for RNA sequences with middle-short length, the MAQGA improves even this state-of-the-art software in terms of both prediction accuracy and sensitivity.


Assuntos
Algoritmos , RNA/química , Sequência de Bases
16.
Phys Rev Lett ; 122(1): 015501, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31012708

RESUMO

It has so far remained a major challenge to quantitatively predict the boson peak, a THz vibrational anomaly universal for glasses, from features in the amorphous structure. Using molecular dynamics simulations of a model Cu_{50}Zr_{50} glass, we decompose the boson peak to contributions from atoms residing in different types of Voronoi polyhedra. We then introduce a microscopic structural parameter to depict the "orientational order," using the vector pointing from the center atom to the farthest vertex of its Voronoi coordination polyhedron. This order parameter represents the most probable direction of transverse vibration at low frequencies. Its magnitude scales linearly with the boson peak intensity, and its spatial distribution accounts for the quasilocalized modes. This correlation is shown to be universal for different types of glasses.

17.
J Chem Phys ; 150(11): 114502, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30902013

RESUMO

This paper presents a set of general strategies for the analysis of structure in amorphous materials and a general approach to assessing the utility of any selected structural description. Two measures of structure are defined, "diversity" and "utility," and applied to two model glass forming binary atomic alloys, Cu50Zr50 and a Lennard-Jones A80B20 mixture. We show that the change in diversity associated with selecting Voronoi structures with high localization or low energy, while real, is too weak to support claims that specific structures are the prime cause of these local physical properties. In addition, a new structure-free measure of incipient crystal-like organization in mixtures is introduced, suitable for cases where the stable crystal is a compound structure.

18.
Phys Chem Chem Phys ; 20(25): 17289-17303, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29901673

RESUMO

To avoid unexpected environmental mechanical failure, there is a strong need to fully understand the details of the oxidation process and intrinsic mechanical properties of reactive metallic iron (Fe) nanowires (NWs) under various aqueous reactive environmental conditions. Herein, we employed ReaxFF reactive molecular dynamics (MD) simulations to elucidate the oxidation of Fe NWs exposed to molecular water (H2O) and hydrogen peroxide (H2O2) environment, and the influence of the oxide shell layer on the tensile mechanical deformation properties of Fe NWs. Our structural analysis shows that oxidation of Fe NWs occurs with the formation of different iron oxide and hydroxide phases in the aqueous molecular H2O and H2O2 oxidizing environments. We observe that the resulting microstructure due to pre-oxide shell layer formation reduces the mechanical stress via increasing the initial defect sites in the vicinity of the oxide region to facilitate the onset of plastic deformation during tensile loading. Specifically, the oxide layer of Fe NWs formed in the H2O2 environment has a relatively significant effect on the deterioration of the mechanical properties of Fe NWs. The weakening of the yield stress and Young modulus of H2O2 oxidized Fe NWs indicates the important role of local oxide microstructures on mechanical deformation properties of individual Fe NWs. Notably, deformation twinning is found as the primary mechanical plastic deformation mechanism of all Fe NWs, but it is initially observed at low strain and stress level for the oxidized Fe NWs.

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