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1.
Front Neurol ; 14: 1290135, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854063

RESUMO

[This corrects the article DOI: 10.3389/fneur.2023.1211108.].

2.
Nanoscale ; 15(37): 15259-15267, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37674458

RESUMO

Elemental antimony (Sb) is regarded as a promising candidate to improve the programming consistency and cycling endurance of phase-change memory and neuro-inspired computing devices. Although bulk amorphous Sb crystallizes spontaneously, the stability of the amorphous form can be greatly increased by reducing the thickness of thin films down to several nanometers, either with or without capping layers. Computational and experimental studies have explained the depressed crystallization kinetics caused by capping and interfacial confinement; however, it is unclear why amorphous Sb thin films remain stable even in the absence of capping layers. In this work, we carry out thorough ab initio molecular dynamics (AIMD) simulations to investigate the effects of free surfaces on the crystallization kinetics of amorphous Sb. We reveal a stark contrast in the crystallization behavior between bulk and surface models at 450 K, which stems from deviations from the bulk structural features in the regions approaching the surfaces. The presence of free surfaces intrinsically tends to create a sub-nanometer region where crystallization is suppressed, which impedes the incubation process and thus constrains the nucleation in two dimensions, stabilizing the amorphous phase in thin-film Sb-based memory devices.

3.
Brain Sci ; 13(7)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37508983

RESUMO

Non-cardioembolic ischemic stroke (IS) is the predominant subtype of IS. This study aimed to construct a nomogram for recurrence risks in patients with non-cardioembolic IS in order to maximize clinical benefits. From April 2015 to December 2019, data from consecutive patients who were diagnosed with non-cardioembolic IS were collected from Lanzhou University Second Hospital. The least absolute shrinkage and selection operator (LASSO) regression analysis was used to optimize variable selection. Multivariable Cox regression analyses were used to identify the independent risk factors. A nomogram model was constructed using the "rms" package in R software via multifactor Cox regression. The accuracy of the model was evaluated using the receiver operating characteristic (ROC), calibration curve, and decision curve analyses (DCA). A total of 729 non-cardioembolic IS patients were enrolled, including 498 (68.3%) male patients and 231 (31.7%) female patients. Among them, there were 137 patients (18.8%) with recurrence. The patients were randomly divided into training and testing sets. The Kaplan-Meier survival analysis of the training and testing sets consistently revealed that the recurrence rates in the high-risk group were significantly higher than those in the low-risk group (p < 0.01). Moreover, the receiver operating characteristic curve analysis of the risk score demonstrated that the area under the curve was 0.778 and 0.760 in the training and testing sets, respectively. The nomogram comprised independent risk factors, including age, diabetes, platelet-lymphocyte ratio, leukoencephalopathy, neutrophil, monocytes, total protein, platelet, albumin, indirect bilirubin, and high-density lipoprotein. The C-index of the nomogram was 0.752 (95% CI: 0.705~0.799) in the training set and 0.749 (95% CI: 0.663~0.835) in the testing set. The nomogram model can be used as an effective tool for carrying out individualized recurrence predictions for non-cardioembolic IS.

4.
Front Neurol ; 14: 1211108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521290

RESUMO

Background: Acute ischemic stroke (AIS) is the leading cause of morbidity and mortality among cerebrovascular diseases. While animal studies have suggested a correlation between cold-inducible RNA-binding protein (CIRP) serum levels and the severity and prognosis of cerebral infarction, there has been a lack of research exploring this association in humans with cerebral infarction. Materials and methods: A total of 148 patients diagnosed with AIS within 7 days from symptom onset were included in this study. Comprehensive information regarding the patients' basic demographics, medical history, clinical parameters, the severity of cerebral infarction, and serum CIRP levels was collected. Follow-up data were obtained through telephonic interviews or by reviewing clinical notes for 3 months after the patients were discharged to assess the functional outcomes of treatment. Results: The findings of this study demonstrated a significant increase in serum CIRP levels during the early stages of AIS, followed by a gradual decline after 3 days. Significant differences were observed in the serum CIRP levels between the 1-day group and the 4-7 day group (P < 0.0047), as well as between the 2-3 day group and the 4-7 day group (P < 0.0006). Moreover, a significant positive correlation was observed between the serum CIRP levels and the severity of cerebral infarction. Higher serum CIRP levels were associated with more severe National Institutes of Health Stroke Scale scores (P < 0.05) and larger cerebral infarction volumes (P < 0.05). Furthermore, patients with higher serum CIRP levels exhibited poorer modified Rankin scale scores (P < 0.05). These findings indicate that serum CIRP serves as an essential pro-inflammatory mediator and a valuable biomarker for assessing brain injury in patients with AIS. Conclusion: The findings of this study suggest an elevation in serum CIRP levels among patients with AIS. These levels are positively correlated with the severity of AIS and serve as indicators of a poor prognosis. Therefore, CIRP could serve as a target for early clinical intervention while managing AIS, and further research should explore serum CIRP levels as prognostic indicators in AIS.

5.
Front Mol Neurosci ; 16: 1076016, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37078089

RESUMO

An ischemic stroke occurs when the blood supply is obstructed to the vascular basin, causing the death of nerve cells and forming the ischemic core. Subsequently, the brain enters the stage of reconstruction and repair. The whole process includes cellular brain damage, inflammatory reaction, blood-brain barrier destruction, and nerve repair. During this process, the proportion and function of neurons, immune cells, glial cells, endothelial cells, and other cells change. Identifying potential differences in gene expression between cell types or heterogeneity between cells of the same type helps to understand the cellular changes that occur in the brain and the context of disease. The recent emergence of single-cell sequencing technology has promoted the exploration of single-cell diversity and the elucidation of the molecular mechanism of ischemic stroke, thus providing new ideas and directions for the diagnosis and clinical treatment of ischemic stroke.

6.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(7): 960-966, 2022 Jul 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36039594

RESUMO

Circular RNA (circRNA) is a covalently closed-loop non-coding RNA that exists widely in the transcriptome of eukaryotic cells. It participates in a variety of pathophysiological processes by acting as a microRNA sponge, regulating the level of protein transcription, and interacting with RNA binding proteins. CircRNA is enriched in the cortex, hippocampus, brain white matter, and photoreceptor neurons of aging bodies, and they can be used as a biomarker for neural senescence. The expression levels of circRNA in peripheral blood and synapses in Alzheimer's disease (AD) patients are increased, which are involved in the occurrence and prognosis of AD. Different circRNAs such as HDAC9, Homer1, Cwc27, Tulp4, and PTK2 can lead to AD pathological changes via increasing amyloid-ß deposition, promoting tau protein hyperphosphorylation, aggravating neuroinflammation and mitochondrial dysfunction, which result in the cognitive decline.


Assuntos
Doença de Alzheimer , MicroRNAs , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Ciclofilinas/metabolismo , Hipocampo/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética
7.
Nanomaterials (Basel) ; 11(11)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34835793

RESUMO

Chalcogenide phase-change materials (PCMs) based random access memory (PCRAM) enter the global memory market as storage-class memory (SCM), holding great promise for future neuro-inspired computing and non-volatile photonic applications. The thermal stability of the amorphous phase of PCMs is a demanding property requiring further improvement. In this work, we focus on indium, an alloying ingredient extensively exploited in PCMs. Starting from the prototype GeTe alloy, we incorporated indium to form three typical compositions along the InTe-GeTe tie line: InGe3Te4, InGeTe2 and In3GeTe4. The evolution of structural details, and the optical properties of the three In-Ge-Te alloys in amorphous and crystalline form, was thoroughly analyzed via ab initio calculations. This study proposes a chemical composition possessing both improved thermal stability and sizable optical contrast for PCM-based non-volatile photonic applications.

8.
Nanoscale Res Lett ; 13(1): 367, 2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30456445

RESUMO

The paper reports a novel flexible full-cell lithium ion battery (LIB) through a simple plastic package method. Carbon nanofibers (CNFs) are synthesized by electrospinning technology and the subsequent carbonation process. The CNFs with three-dimensional interconnected fibrous nanostructure exhibit a stable reversible capacity of 412 mAh g-1 after 100 cycles in the half-cell testing. A full cell is assembled by using CNF anode and commercial LiCoO2 cathode, and it displays good flexibility and lighting LED ability. The aggregate thickness of the constructed full-cell LIB is approximately 500 µm, consisting of a CNFs/Cu film, a separator, a LiCoO2/Al film, electrolyte, and two polyvinyl chloride (PVC) films. The structure, morphology, and the electrochemical performances of electrospun CNFs and LiCoO2 electrodes are analyzed in details.

9.
ACS Appl Mater Interfaces ; 5(8): 3118-25, 2013 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-23532681

RESUMO

ZnO-loaded/porous carbon (PC) composites with different ZnO loading amounts are first synthesized via a facile solvothermal method and evaluated for anode materials of lithium ion batteries. The architecture and the electrochemical performance of the as-prepared composites are investigated through structure characterization and galvanostatic charge/discharge test. The ZnO-loaded/PC composites possess a rich porous structure with well-distributed ZnO particles (size range: 30-100 nm) in the PC host. The one with 54 wt % ZnO loading contents exhibits a high reversible capacity of 653.7 mA h g(-1) after 100 cycles. In particular, a capacity of 496.8 mA h g(-1) can be reversibly obtained when cycled at 1000 mA g(-1). The superior lithium storage properties of the composite may be attributed to its nanoporous structure together with an interconnected network. The modified interfacial reaction kinetics of the composite promotes the intercalation/deintercalation of lithium ions and the charge transfer on the electrode. As a result, the enhanced capacity of the composite electrode is achieved, as well as its high rate capability.

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