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An extended crystal plasticity model and an optimized neural network are established to investigate the mechanical behavior of CoCrNiSi0.3C0.048 Medium entropy alloy (MEA) with a three-level hierarchical precipitation structure under dynamic compressive deformation at a variety of ranges of strain rates. The interaction between the matrix and first-level precipitates is described by a presented hybrid representative volume element RVE model, involving the effects of volume fraction (Vf), radius and geometric distribution on heterogeneous deformation. Effects of second- and third-level precipitates are realized through the extended crystal plasticity constitutive model, reflecting the motion mechanism of dislocations near the precipitates in the form of initial slip resistance. Meanwhile, this study investigates the influence of the presence of primary precipitates on the initiation of slip systems within special grains with Goss or S orientations in the matrix. Additionally, it provides a more in-depth explanation of the underlying principles behind the suppression of Goss texture formation by the precipitates from the perspective of slip systems analysis. The changing of volume fractions affects flow stress evolution. Avoiding suffering from expensive computational consumption by the crystal plasticity finite element method, an artificial neural network model optimized through a genetic algorithm, is presented to predict stress-strain responses and texture evolution results under varying compression strain rates. A reliable dataset derived from crystal plasticity finite element models and experimental results is utilized to train, test, and validate the genetic algorithm-based artificial neural network model. This model demonstrates good prediction capability in dynamic mechanical behavior and texture evolution, showcasing the feasibility and efficacy of the proposed neural network model. Compared to the CPFEM method, neural network models can greatly improve computational efficiency.

Recent studies confirmed that introducing nanoprecipitates as strengthening phase into high-entropy alloys (HEAs) is an extremely effective means to achieve the excellent strength-ductility synergy. In this work, we successfully created a dual nanoscale precipitate structure in a Co-free Ni2.5CrFeAl0.3Ti0.2 HEA by controlling thermo-mechanical process. Compared to the recrystallized alloy, homogeneous L12 precipitates in FCC matrix and heterogeneous L12/BCC precipitates near grain boundaries were formed in the aged alloys. The dual-nanoprecipitate structure induces a long-range back stress during deformation process, effectively contributing to a balance of high strength and good ductility at 298K. Especially, the mechanical properties of the recrystallized and aged alloys are dramatically improved without strength-ductility tradeoff, showing a multiple-stage strain-hardening behavior at 77 K. In the aged alloys, the nanoprecipitates shorten the mean free path of dislocation movement to effectively induce the precipitation strengthening appreciably depending on the precipitation size. Different from planar dislocations slip dominated by stacking faults at 298K, multiple stacking fault networks and deformation twins were activated sequentially with increasing the tensile strain, thus forming a dynamic Hall-Petch effect at 77K. The current work could help to understand the correlation between mechanical properties and deformation mechanisms in precipitation-strengthening HEAs, and the transformation of these deformation mechanisms provide an insight for developing outstanding-performance HEAs through trigging various hardening modes.

A massless particle beyond the Standard Model is searched for in the two-body decay Σ+→p+invisible using (1.0087±0.0044)×1010 J/ψ events collected at a center-of-mass energy of s=3.097GeV with the BESIII detector at the BEPCII collider. No significant signal is observed, and the upper limit on the branching fraction B(Σ+→p+invisible) is determined to be 3.2×10−5 at the 90% confidence level. This is the first search for a flavor-changing neutral current process with missing energy in hyperon decays which plays an important role in constraining new physics models.

In this paper, the effects of Zr addition on the microstructure evolution, GFA and mechanical properties of the Ti55-xZrxCu22.5Be22.5 (x ​= ​0–30) alloys were investigated. The experimental results indicate that the Zr addition changes the phase competition and enhances the stabilization of the melting liquid, thereby improves the GFA of the present alloys. The monolithic BMGs of Ti55-xZrxCu22.5Be22.5 (x ​= ​20–30) with a diameter of at least 10 ​mm can be fabricated by the water-cooled copper mold casting. These BMGs also exhibit excellent mechanical properties with 1700 ​MPa fractured strength and >8% plastic strain. The developed new Ti–Zr–Cu–Be BMGs not only have good GFA and mechanical properties, but also are insensitive to composition and have a wide composition window. This is very beneficial for industrial production and engineering application. The present results also provide a new perspective for improving the GFA and plasticity.

A novel Z-scheme graphitic C3N4/reduced TiO2 microsphere (g-C3N4/r-TiO2) has been successfully synthesized by a solvothermal method. The as-prepared samples with different contents of g-C3N4 were characterized by X-ray diffraction, electron paramagnetic resonance, scanning electron microscope, UV–vis. diffuse reflectance and photoluminescence spectra. The r-TiO2 microspheres are aggregated on the surface of g-C3N4 sheets in the as-prepared g-C3N4/r-TiO2 composites. All g-C3N4/r-TiO2 catalysts show enhanced photocatalytic activity for the degradation of rhodamine B under visible light irradiation. It could be attributed to these influences of oxygen vacancy (changing the band gap of TiO2), the large specific surface area (providing much more active sites for photocatalytic reaction), and the synergetic effect between g-C3N4 and r-TiO2 (promoting the separation for photoinduced electron-hole pairs). Moreover, the Z-scheme carriers transfer mechanism in the photocatalytic process has been discussed through trapping experiments of active species. The work demonstrates the strategies of the construction of Z-scheme carriers transfer system, the introduction of oxygen vacancy and structure designing are beneficial to design materials toward solar energy conversion like contaminant degradation. Keywords: TiO2, C3N4, Oxygen vacancy, Z-scheme heterojunction, Photocatalytic performance

The microRNAs are non-coding RNA molecules of approximately 20-22 nucleotides that are found to be implicated in a wide range of physiological processes. In this study, the suitability of 10 candidate reference RNAs was evaluated for microRNA expression data in the skin tissue of Liaoning cashmere goat including 1 small nuclear RNA (snRNA; RNU6B), 1 small nucleolar RNA (snoRNA; Z30), 1 rRNA (5S), 1 transfer RNA (tRNA; Met-tRNA), and 6 microRNAs (miR; let-7d-5p, miR-15a-5p, miR-26a-5p, miR-125a-5p, miR-214-3p, and miR-221-3p). Based on geNorm and NormFinder algorithms, we identified let-7d-5p, miR-26a-5p, and miR-15a-5p as the most stable reference RNAs. Also, three reference RNAs (let-7d-5p, miR-26a-5p, and miR-15a-5p) were sufficient for the normalization of microRNA expression data in the skin of this breed. We further assessed the suitability of let-7d-5p, miR-26a-5p, and miR-15a-5p in a combination as reference RNAs through detecting the relative expression of miR-24-3p, miR-29a-3p, miR-145a-5p, and miR-205-5p as putative genes of interest. Significant differences were revealed in the relative expression of miR-24-3p, miR-29a-3p, miR-145a-5p, and miR-205-5p at telogen stage of hair follicle cycle when a combination of let-7d-5p, miR-26a-5p, and miR-15a-5p vs a single let-7d-5p were used as reference RNA. Based on the results from this study, we suggested that the combination of let-7d-5p, miR-26a-5p, and miR-15a-5p as normalizers for microRNA expression data would be more reliable than that of single let-7d-5p, and the geometric mean of these three microRNAs (let-7d-5p, miR-26a-5p, and miR-15a-5p) can be used for the normalization of microRNAs expression data in the skin of Liaoning cashmere goat.

In Northwestern China, the carbon fixing capacity of black locust (Robinia pseudoacacia) has been questioned because of its slow growth following the return of unproductive farmland to forest. To explore the effects of stand age on the carbon sequestration potential of R. pseudoacacia in a semi-arid, ecologically fragile area, parameters related to carbon fixation were investigated in plots of three stand ages (5, 10, and 25 years). Each plot was divided into four subsystems: R. pseudoacacia, understory vegetation, litter, and soil, and the carbon stored capacity of each subsystem was estimated. The organic carbon density of R. pseudoacacia, understory vegetation, and litter ranged from 3.4-16.8% and increased gradually with increasing stand age. Soil organic carbon increased with increasing stand age and accounted for 83.2-96.6% of the total carbon stored. Soil CaCO3 content also increased with increasing soil depth and stand age. Because total plant and soil carbon storage increased with increasing age of R. pseudoacacia stands, the 25-year-old R. pseudoacacia community had the highest carbon fixation capacity, which was substantial even in this arid region.

Ginsenoside Rg1, one of the most notable active components of Panax ginseng, has been widely reported to exert anti-inflammatory actions. This study aimed to reveal whether ginsenoside Rg1 also exhibits beneficial roles against lipopolysaccharide (LPS)-induced apoptosis and inflammation in human renal tubular epithelial cells, and to evaluate the potential role of the component on tubulointerstitial nephritis treatment. HK-2 cells were treated with various doses of ginsenoside Rg1 (0, 50, 100, 150, and 200 μM) in the absence or presence of 5 μg/mL LPS. Thereafter, CCK-8 assay, flow cytometry, western blot, migration assay, reactive oxygen species (ROS) assay, and ELISA were carried out to respectively assess cell viability, apoptosis, migration, ROS activity, and the release of inflammatory cytokines. As a result, ginsenoside Rg1 protected HK-2 cells from LPS-induced injury, as cell viability was increased, cell apoptosis was decreased, and the release of MCP-1, IL-1β, IL-6, and TNF-α was reduced. Ginsenoside Rg1 functioned to HK-2 cells in a dose-dependent manner, and the 150 μM dose exhibited the most protective functions. Ginsenoside Rg1 had no significant impact on cell migration and ROS activity, while it alleviated LPS-induced ROS release and migration impairment. Furthermore, the down-regulations of p-PI3K, p-AKT, and up-regulations of PTEN, p-IκBα, p-p65, Bcl-3 induced by LPS were recovered to some extent after ginsenoside Rg1 treatment. In conclusion, ginsenoside Rg1 protects HK-2 cells against LPS-induced inflammation and apoptosis via activation of the PI3K/AKT pathway and suppression of NF-κB pathway.

The impacts of tillage system (conventional tillage and no-tillage) and residue management (0, 50, and 100%) on soil properties and soil microbial community structure were determined in the Fengqiu State Key Agro-Ecological Experimental Station, North China. The microbial community structure was investigated by phospholipid fatty acid (PLFA) profiles. The results showed that tillage had significant effects on soil properties and soil microbial communities. In no-tillage (NT), microbial biomass carbon (MBC), total N, microbial biomass carbon/soil organic carbon (MBC/SOC), total microbes, and arbuscular mycorrhiza fungi increased, while actinomycetes, G+/G- bacteria ratio and monounsaturated fatty acids/saturated fatty acids (MUFA/STFA) decreased, compared with those in conventional tillage (CT). Residue had a significant positive effect on C/N ratio and MUFA/STFA. Canonical correspondence analysis indicated that tillage explained 76.1%, and residue management explained 0.6% of the variations in soil microbial communities, respectively. Soil microbial communities were significantly correlated with MBC, total N, C/N ratio and MBC/SOC. Among the six treatments, NT with 100% residue application obviously improved soil microbiological properties, and could be a proper management practice in the Huang-Huai-Hai Plain of China.

Brain damage caused by small vessel disease (SVD) differs between males and females. We aimed to examine the pure sex-specific neuroanatomical mechanisms of SVD adjusted for voxel-based expected effects of age and sex on healthy brain volume. Thirty-one female and 32 male genetic SVD (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, CADASIL) patients and 55 sex- and age-matched healthy controls (HCs) underwent 7-Tesla MRI examinations. Voxel-based W-score maps were calculated from volumes and deformations of brain tissues, controlling for the expected effects of age and sex in HCs. Significant cognitive declines in working memory and executive function were identified in male CADASIL patients compared to female patients. Greater gray matter (GM) atrophy was found in the bilateral orbitofrontal cortex (OFC), left anterior cingulate cortex (ACC), left entorhinal cortex (EC), and right temporooccipital cortex in male CADASIL patients than in females. Working memory was associated with volumes in the right OFC specific to female CADASIL patients, whereas visuospatial ability was associated with the right hOcl (primary visual area, BA 17) volume specific to males. The current findings indicate that sex affects the pathogenesis of CADASIL, ranging from differences in neuroanatomy to those in behavioral performance, which may facilitate the development of more effective sex-specific therapeutic strategies for CADASIL and SVD.

Background: Perivascular spaces on brain magnetic resonance imaging (MRI) may indicate poor fluid drainage in the brain and have been associated with numerous neurological conditions. Cerebrovascular reactivity (CVR) is a marker of cerebrovascular function and represents the ability of cerebral blood vessels to regulate cerebral blood flow in response to vasodilatory or vasoconstrictive stimuli. We aimed to examine whether pathological widening of the perivascular space in older adults may be associated with deficits in CVR. Methods: Independently living older adults free of dementia or clinical stroke were recruited from the community and underwent brain MRI. Pseudo-continuous arterial spin labeling MRI quantified whole brain cerebral perfusion at rest and during CVR to hypercapnia and hypocapnia induced by visually guided breathing exercises. Perivascular spaces were visually scored using existing scales. Results: Thirty-seven independently living older adults (mean age = 66.3 years; SD = 6.8; age range 55–84 years; 29.7% male) were included in the current analysis. Multiple linear regression analysis revealed a significant negative association between burden of perivascular spaces and global CVR to hypercapnia (B = -2.0, 95% CI (-3.6, -0.4), p = .015), adjusting for age and sex. Perivascular spaces were not related to CVR to hypocapnia. Discussion: Perivascular spaces are associated with deficits in cerebrovascular vasodilatory response, but not vasoconstrictive response. Enlargement of perivascular spaces could contribute to, or be influenced by, deficits in CVR. Additional longitudinal studies are warranted to improve our understanding of the relationship between cerebrovascular function and perivascular space enlargement.

Transcranial direct current stimulation (tDCS) can influence performance on behavioral tasks and improve symptoms of brain conditions. Yet, it remains unclear precisely how tDCS affects brain function and connectivity. Here, we measured changes in functional connectivity (FC) metrics in blood-oxygenation-level-dependent (BOLD) fMRI data acquired during MR-compatible tDCS in a whole-brain analysis with corrections for false discovery rate. Volunteers (n = 64) received active tDCS, sham tDCS, and rest (no stimulation), using one of three previously established electrode tDCS montages targeting left dorsolateral prefrontal cortex (DLPFC, n = 37), lateral temporoparietal area (LTA, n = 16), or superior temporal cortex (STC, n = 11). In brain networks where simulated E field was highest in each montage, connectivity with remote nodes decreased during active tDCS. During active DLPFC-tDCS, connectivity decreased between a fronto-parietal network and subgenual ACC, while during LTA-tDCS connectivity decreased between an auditory-somatomotor network and frontal operculum. Active DLPFC-tDCS was also associated with increased connectivity within an orbitofrontal network overlapping subgenual ACC. Irrespective of montage, FC metrics increased in sensorimotor and attention regions during both active and sham tDCS, which may reflect the cognitive-perceptual demands of tDCS. Taken together, these results indicate that tDCS may have both intended and unintended effects on ongoing brain activity, stressing the importance of including sham, stimulation-absent, and active comparators in basic science and clinical trials of tDCS.

Laminar fMRI based on BOLD and CBV contrast at ultrahigh magnetic fields has been applied for studying the dynamics of mesoscopic brain networks. However, the quantitative interpretations of BOLD/CBV fMRI results are confounded by different baseline physiology across cortical layers. Here we introduce a novel 3D zoomed pseudo-continuous arterial spin labeling (pCASL) technique at 7T that offers the capability for quantitative measurements of laminar cerebral blood flow (CBF) both at rest and during task activation with high spatial specificity and sensitivity. We found arterial transit time in superficial layers is ∼100 ms shorter than in middle/deep layers revealing the time course of labeled blood flowing from pial arteries to downstream microvasculature. Resting state CBF peaked in the middle layers which is highly consistent with microvascular density measured from human cortex specimens. Finger tapping induced a robust two-peak laminar profile of CBF increases in the superficial (somatosensory and premotor input) and deep (spinal output) layers of M1, while finger brushing task induced a weaker CBF increase in superficial layers (somatosensory input). This observation is highly consistent with reported laminar profiles of CBV activation on M1. We further demonstrated that visuospatial attention induced a predominant CBF increase in deep layers and a smaller CBF increase on top of the lower baseline CBF in superficial layers of V1 (feedback cortical input), while stimulus driven activity peaked in the middle layers (feedforward thalamic input). With the capability for quantitative CBF measurements both at baseline and during task activation, high-resolution ASL perfusion fMRI at 7T provides an important tool for in vivo assessment of neurovascular function and metabolic activities of neural circuits across cortical layers.

Cerebrovascular reactivity (CVR), which measures the ability of cerebral blood vessels to dilate or constrict in response to vasoactive stimuli such as CO2 inhalation, is an important index of the brain's vascular health. Quantification of CVR using BOLD MRI with hypercapnia challenge has shown great promises in research and clinical studies. However, in order for it to be used as a potential imaging biomarker in large-scale and multi-site studies, the reliability of CO2-CVR quantification across different MRI acquisition platforms and researchers/raters must be examined. The goal of this report from the MarkVCID small vessel disease biomarkers consortium is to evaluate the reliability of CO2-CVR quantification in three studies. First, the inter-rater reliability of CO2-CVR data processing was evaluated by having raters from 5 MarkVCID sites process the same 30 CVR datasets using a cloud-based CVR data processing pipeline. Second, the inter-scanner reproducibility of CO2-CVR quantification was assessed in 10 young subjects across two scanners of different vendors. Third, test-retest repeatability was evaluated in 20 elderly subjects from 4 sites with a scan interval of less than 2 weeks. In all studies, the CO2 CVR measurements were performed using the fixed inspiration method, where the subjects wore a nose clip and a mouthpiece and breathed room air and 5% CO2 air contained in a Douglas bag alternatively through their mouth. The results showed that the inter-rater CoV of CVR processing was 0.08 ± 0.08% for whole-brain CVR values and ranged from 0.16% to 0.88% in major brain regions, with ICC of absolute agreement above 0.9959 for all brain regions. Inter-scanner CoV was found to be 6.90 ± 5.08% for whole-brain CVR values, and ranged from 4.69% to 12.71% in major brain regions, which are comparable to intra-session CoVs obtained from the same scanners on the same day. ICC of consistency between the two scanners was 0.8498 for whole-brain CVR and ranged from 0.8052 to 0.9185 across major brain regions. In the test-retest evaluation, test-retest CoV across different days was found to be 18.29 ± 17.12% for whole-brain CVR values, and ranged from 16.58% to 19.52% in major brain regions, with ICC of absolute agreement ranged from 0.6480 to 0.7785. These results demonstrated good inter-rater, inter-scanner, and test-retest reliability in healthy volunteers, and suggested that CO2-CVR has suitable instrumental properties for use as an imaging biomarker of cerebrovascular function in multi-site and longitudinal observational studies and clinical trials.

Abstract Introduction We investigated the hypothesis that retinal capillary perfusion is a biomarker of early cognitive decline and cerebrovascular perfusion associated with small vessel disease in a pilot data set of Latinx adults at high risk for vascular cognitive impairment and dementia. Methods High‐resolution optical coherence tomography angiography (OCTA) images were acquired from dilated eyes of Latinx subjects using a 3 × 3 mm2 scan pattern from a commercially available device. A previously validated method was used to quantify the density of perfused retinal capillaries as the retinal vessel skeleton density (VSD). The association of VSD with Clinical Dementia Rating Sum of Boxes, total Montreal Cognitive Assessment (MoCA) score, and individual MoCA test elements were analyzed using multivariate statistics that adjusted for confounders. VSD was also compared with magnetic resonance imaging (MRI) measures of cerebrovascular reactivity (CVR) and perfusion in the middle cerebral artery perforator (MCA‐Perf) territory. Results The mean (± SD) age of the subjects was 68 (± 6) years. For every 0.01‐unit lower VSD, the risk of having a CDR‐SOB >0 was 20% higher (95%CI = 5%–90%; P = .031). Similarly, a lower VSD was associated with lower total MoCA score (r = 0.3; P = .038). The Visuospatial/Executive domain of the MoCA assessment showed the strongest association with VSD (β = 0.02; P = .022). Lower retinal VSD was associated with worse MRI measure of CVR (r = 0.7, P = .04) and less perfusion in the MCA‐Perf territory (r = 0.45, P = .02). Discussion Impaired retinal capillary perfusion is associated with cognitive impairment and abnormalities in cerebrovascular perfusion and function. OCTA‐based retinal capillary assessment holds promise for identifying and quantifying retinal correlates of neurovascular abnormalities associated with vascular cognitive impairment.

Autosomal dominant Alzheimer's disease (ADAD) is a small subset of Alzheimer's disease that is genetically determined with 100% penetrance. It provides a valuable window into studying the course of pathologic processes that leads to dementia. Arterial spin labeling (ASL) MRI is a potential AD imaging marker that non-invasively measures cerebral perfusion. In this study, we investigated the relationship of cerebral blood flow measured by pseudo-continuous ASL (pCASL) MRI with measures of cerebral metabolism (FDG PET) and amyloid deposition (Pittsburgh Compound B (PiB) PET). Thirty-one participants at risk for ADAD (age 39±13years, 19 females) were recruited into this study, and 21 of them received both MRI and FDG and PiB PET scans. Considerable variability was observed in regional correlations between ASL-CBF and FDG across subjects. Both regional hypo-perfusion and hypo-metabolism were associated with amyloid deposition. Cross-sectional analyses of each biomarker as a function of the estimated years to expected dementia diagnosis indicated an inverse relationship of both perfusion and glucose metabolism with amyloid deposition during AD development. These findings indicate that neurovascular dysfunction is associated with amyloid pathology, and also indicate that ASL CBF may serve as a sensitive early biomarker for AD. The direct comparison among the three biomarkers provides complementary information for understanding the pathophysiological process of AD. Keywords: Autosomal dominant Alzheimer's disease, Arterial spin labeling, MRI, FDG pet, PiB PET, Cerebral perfusion, Glucose metabolism, Amyloid deposition