We report an in-situ study of the deformation-induced rotation and transformation of austenite grains in a low-carbon steel treated by the quenching and partitioning process using electron ...back-scattered diffraction and uniaxial tension experiments. It was found that retained austenite could be classified into four types according to different locations in the microstructure: retained austenite at triple edges, twinned austenite, retained austenite distributed between martensite and retained austenite embedded completely in a single ferrite. The results showed that at the early stage of deformation, the retained austenite at the triple edges and twinned austenite transformed easily, while the retained austenite at the boundaries between martensite and that embedded completely in a single ferrite rotated with no transformation; and did not transform until a large deformation was provided. This phenomenon implies that the retained austenite at the boundaries between martensite and that embedded completely in a single ferrite are more capable of resisting deformation. From the observations of Schmid factor maps and the texture of retained austenite, it can be concluded that the rotation of retained austenite followed a particular slip plane and slip direction. Moreover, the rotation of retained austenite could improve the ductility of the material. In comparison with the film-like retained austenite distributed between martensite, the retained austenite embedded completely in a single ferrite could resist a larger rotation angle, i.e. the latter could contribute more to the ductility of the steel. In addition, from the analysis of kernel average misorientation that the strain distribution mainly concentrated near the α−γ phase boundaries and in the interior of martensite, and the rotation angles and dislocation density of austenite increase with increasing strain.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Explore serum levels of hypoxia-inducible factor-1α (HIF-1α), signal transduction molecule 3 (SMAD3), and histone deacetylase (HDAC) and their correlation with the severity of the condition of stroke ...patients.
Clinical records of 93 stroke patients and 93 healthy individuals were retrospectively analyzed. Serum levels of HIF-1α, SMAD3, and HDAC3 in patients with different disease degrees and lesion areas were compared between the two groups. Correlation between serum levels of HIF-1α, SMAD3, and HDAC3 and the severity and lesion area of the observation group were analyzed.
Serum levels of HIF-1α, SMAD3, and HDAC3 in the observation group were higher than those in the control group (p<0.05). Serum levels of HIF-1α, SMAD3, and HDAC3 in patients with moderate and severe disease were significantly higher than those in patients with mild disease and were the highest in patients with severe disease (p<0.05). Serum levels of HIF-1α, SMAD3, and HDAC3 in patients with moderate and large areas of cerebral infarction were significantly higher than those in patients with small areas of cerebral infarction and the highest in patients with large areas of cerebral infarction (p<0.05). Spearman correlation analysis showed that serum levels of HIF-1α, SMAD3, and HDAC3 significantly positively correlated with the severity of stroke and lesion area (p<0.05).
Serum levels of HIF-1α, SMAD3, and HDAC3 in stroke patients are highly expressed, and the increase positively correlates with the severity of the disease and the area of the lesion.
We simulate the evolution of the stellar wind and the supernova remnant (SNR) originating from a runaway massive star in a uniform Galactic environment based on three-dimensional magnetohydrodynamics ...models. Taking the stellar wind into consideration, we can explain the radio morphologies of many SNRs. The directions of the kinematic velocity of the progenitor, the magnetic field, and the line of sight are the most important factors influencing the morphologies. If the velocity is perpendicular to the magnetic field, the simulation will give us two different unilateral SNRs and a bilateral symmetric SNR. If the velocity is parallel to the magnetic field, we obtain a bilateral asymmetric SNR and a quasi-circular SNR. Our simulations show the stellar wind plays a key role in the radio evolution of an SNR, which implies that the Galactic global density and magnetic field distribution play a secondary role.
Sun J, Chen C, Jiang G, Tian W, Li Y, Sun S. Int J Nanomedicine. 2014;9(1):1339-1346. An error during the preparation of Figure 3 for publishing led to the inadvertent creation of a duplicate region ...in figure part 3A on page 1342. The journal wishes to apologise for this error. The correct version of Figure 3 is shown below. Figure 3 The different Ki67 expressions detected by QD-IHC (A and C) and IHC (B and D) in the same specimens.Abbreviations: IHC, immunohistochemistry; QD-IHC, quantum dot-immunohistochemistry.Notes: (A and B) are the same specimens; (C and D) are the same specimens. Scale bar: 25 μm.
A load-bearing, multifunctional material with the simultaneous capability to store energy and withstand static and dynamic mechanical stresses is demonstrated. This is produced using ion-conducting ...polymers infiltrated into nanoporous silicon that is etched directly into bulk conductive silicon. This device platform maintains energy densities near 10 W h/kg with Coulombic efficiency of 98% under exposure to over 300 kPa tensile stresses and 80 g vibratory accelerations, along with excellent performance in other shear, compression, and impact tests. This demonstrates performance feasibility as a structurally integrated energy storage material broadly applicable across renewable energy systems, transportation systems, and mobile electronics, among others.
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IJS, KILJ, NUK, PNG, UL, UM
Abstract
Alzheimer's disease is a neurodegenerative disorder associated with the deposition of the peptide amyloid-beta (Aβ) in senile plaques and cerebral vasculature. The neurotoxic mechanisms of ...this condition have been linked to oxidative-stress-induced apoptosis leading to widespread neuronal loss. Herein, we demonstrate the neuroprotective effects of a ketone body D-β-hydroxybutyrate (β-HB) in neural cell lines and an animal model induced by injecting Aβ into the hippocampus. Using histological examination and the TUNEL assay, we show that administration of exogenous β-HB effectively prevents Aβ deposition and neuron apoptosis in this rat model. β-HB pretreatment also relieves the oxidative stress in Aβ-induced PC-12 cells, as shown by decreased intracellular reactive oxygen species and Ca2+ levels, activated Nrf2 and recovered superoxide dismutase and catalase activities. Consequently, the apoptotic pathway is also inhibited in these cells, with decreased levels of p53, caspase-12, caspase-9, caspase-3; a decreased Bax/Bcl-2 ratio; and decreased cytochrome c release. Taken together, our study provides a molecular basis for the neuroprotective effects of β-HB in line with the suppression of oxidative stress and the inhibition of apoptotic protein activation.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
To investigate the relationship between the cross-sectional visceral adipose tissue (VAT) areas at different anatomic sites and the total VAT volume in a healthy Chinese population using quantitative ...computed tomography (QCT), and to identify the optimal anatomic site for a single slice to estimate the total VAT volume.
A total of 389 healthy Chinese subjects aged 19-63 years underwent lumbar spine QCT scans. The cross-sectional area of total adipose tissue and VAT were measured using the tissue composition module of the software (QCT Pro, Mindways) at each intervertebral disc level from T
/L
to L
/S
, as well as at the umbilical level. The total VAT volume was defined as the fat areas multiplied by the height of vertebral body for all six slices. Statistical analysis was performed to determine the correlation between single-slice VAT areas and the total VAT volume. Moreover, the optimal anatomic site for a single slice to estimate the total VAT volume was identified by multiple regression analysis.
The cross-sectional area of VAT and subcutaneous adipose tissue (SAT) measured at each anatomic site was all highly correlated with the total VAT volume and the total SAT volume (r = 0.89-0.98). Additionally, the VAT area measured at the L
/L
level showed the strongest correlation with the total VAT volume (r = 0.98, P < 0.001). Covariates including age, gender, BMI, waist, and hypertension make a slight effect on the prediction of the total VAT volume.
It is feasible to perform measurements of VAT area on a single slice at L
/L
level for estimating the total VAT volume.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, VSZLJ, ZAGLJ
•The upper and lower response bounds are obtained through a series of sequential simulations.•The proposed sequential simulation method is applicable to interval uncertainty analysis of structural or ...system response with multiple DOFs.•The contributive samples for the response bounds over the whole concerned domain can be identified simultaneously.•The sequential simulation strategy is demonstrated to be more efficient than the direct MC simulation for response bounds evaluation.
Prediction of response bounds of structures with interval uncertainties is a major concern in interval finite element analysis. In many cases, the structural response is a variable regarding to physical parameters such as location, node, time, or other degrees of freedom. Different kinds of interval methods have been proposed and developed for response bounds analysis, which mainly include the interval arithmetic-based methods, optimization methods, perturbation methods, etc. This paper proposes a sequential simulation strategy for response bounds analysis of structures with interval uncertainties, through which we aim to find the upper and lower bounds by implementing the simulation procedure sequentially. The proposed sequential simulation strategy suggests an initial sampling and simulation, from which those contributive samples that result in the current upper or lower response bound are retained. In the subsequent simulation sequence, local samples within neighborhoods of the present contributive samples as well as a set of global samples are generated for the input interval uncertainties. With such a simulation procedure, the response bounds are expected to expand outwards sequentially until convergence. By illustration and comparison, the proposed sequential simulation strategy is proved to be more efficient than the direct simulation method for structural response bounds analysis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract This study presents a comprehensive analysis of the spectral properties of 886 pulsars across a wide frequency range from 20 MHz–343.5 GHz, including a total of 86 millisecond pulsars ...(MSPs). The majority of the pulsars exhibit power-law behavior in their spectra, although some exceptions are observed. Five different spectral models, namely, simple power law, broken power law, low-frequency turnover, high-frequency cutoff, and double turnover, were employed to explore the spectral behaviors. The average spectral index for pulsars modeled with a simple power law is found to be −1.64 ± 0.80, consistent with previous studies. Additionally, significant correlations between the spectral index and characteristic parameters are observed, particularly in MSPs, while no strong correlation is observed in normal pulsars. Different models show variations in the most influential characteristic parameters associated with the spectral index, indicating diverse dominant radiation mechanisms in MSPs. Finally, this study identifies 22 pulsars of the gigahertz-peaked spectra type for the first time based on the Akaike information criterion.
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