It remains a great challenge to design and manufacture battery‐type supercapacitors with satisfactory flexibility, appropriate mechanical property, and high energy density under high power density. ...Herein, a concept of porous engineering is proposed to simply prepare two‐layered bimetallic heterojunction with porous structures. This concept is successfully applied in fabrication of flexible electrode based on CuO‐Co(OH)2 lamella on Cu‐plated carbon cloth (named as CPCC@CuO@Co(OH)2). The unique structure brings the electrode a high specific capacity of 3620 mF cm−2 at 2 mA cm−2 and appropriate mechanical properties with Young's modulus of 302.0 MPa. Density functional theory calculations show that porous heterojunction provides a higher intensity of electron state density near the Fermi level (E–Ef = 0 eV), leading to a highly conductive CPCC@CuO@Co(OH)2 electrode with both efficient charge transport and rapid ion diffusion. Notably, the supercapacitor assembled from CPCC@CuO@Co(OH)2//CC@AC shows high energy density of 127.7 W h kg−1 at 750.0 W kg−1, remarkable cycling performance (95.53% capacity maintaining after 10 000 cycles), and desired mechanical flexibility. The methodology and results in this work will accelerate the transformative developments of flexible energy storage devices in practical applications.
A universal strategy for constructing lamellar porous heterojunctions is developed to fabricate flexible electrodes for high‐performance energy storage devices. The resulted electrodes have a unique energy band structure with higher electronic density of states near the Fermi level and high conductivity, which achieve efficient charge transport and shortened the ion diffusion distance.
High‐entropy‐alloy nanoparticles (HEA‐NPs) have attracted great attention because of their unique complex compositions and tailorable properties. Further expanding the compositional space is of great ...significance for enriching the material library. Here, a step‐alloying strategy is developed to synthesis HEA‐NPs containing a range of strongly repellent elements (e.g., Bi–W) by using the rich‐Pt cores formed during the first liquid phase reaction as the seed of the second thermal diffusion. Remarkably, the representative HEA‐NPs‐(14) with up to 14 elements exhibits extremely excellent multifunctional electrocatalytic performance for pH‐universal hydrogen evolution reaction (HER), alkaline methanol oxidation reaction (MOR), and oxygen reduction reaction (ORR). Briefly, HEA‐NPs‐(14) only requires the ultralow overpotentials of 11 and 18 mV to deliver 10 mA cm−2 and exhibits ultralong durability for 400 and 264 h under 100 mA cm−2 in 0.5 m H2SO4 and 1 m KOH, respectively, which surpasses most advanced pH‐universal HER catalysts. Moreover, HEA‐NPs‐(14) also exhibits an impressive peak current density of 12.6 A mg−1Pt in 1 m KOH + 1 m MeOH and a half‐wave potential of 0.86 V (vs RHE.) in 0.1 m KOH. The work further expands the spectrum of possible metal alloys, which is important for the broad compositional space and future data‐driven material discovery.
A step‐alloying strategy is developed to prepare a series of high‐entropy‐alloy nanoparticle (HEA‐NP) systems that contain many strongly immiscible element pairs, including Bi–W with the highest ΔHmix of 45 kJ mol−1. This strategy further expands the spectrum of possible metal alloys, which is significant for the broad compositional space and future data‐driven material discovery.
Carbon nanotube (CNT) polymer composites exhibit strong nonlinear and asymmetric piezoresistivity about zero strain in tensile and compressive strain states. The existing models explain the ...characteristic qualitatively but not quantitatively. This paper attempts to understand the mechanisms of this piezoresistivity by developing a new 3-dimensional percolation CNT network model, where the effect of CNT deformation (wall indentation and tube bending) is considered for the first time. The predicted electrical conductivity and piezoresistivity agree with experiments quantitatively, which reveals that the CNT deformation is a dominant mechanism for the nonlinearity and asymmetry of piezoresistivity of CNT-polymer composites. Parametric studies have been conducted to show the effects of morphology and electrical properties of CNTs, work functions and Poisson's ratio of polymer on the piezoresistivity of CNT-polymer composites for future application in nanosensing composites.
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•The mechanisms of piezoresistivity of CNT–polymer composites are studied by tunneling theory and Landauer–Büttiker formula.•The CNT deformation is found as a dominant mechanism for nonlinearity and asymmetry of piezoresistivity of the composites.•Effects of morphology and electrical properties of CNTs, work functions and Poisson's ratio of polymer on piezoresistivity are studied.
Remdesivir (RDV), a single diastereomeric monophosphoramidate prodrug that inhibits viral RNA polymerases, has potent in vitro antiviral activity against severe acute respiratory syndrome‐coronavirus ...2 (SARS‐CoV‐2). RDV received the US Food and Drug Administration (FDA)’s emergency use authorization in the United States and approval in Japan for treatment of patients with severe coronavirus disease 2019 (COVID‐19). This report describes two phase I studies that evaluated the safety and pharmacokinetics (PKs) of single escalating and multiple i.v. doses of RDV (solution or lyophilized formulation) in healthy subjects. Lyophilized formulation was evaluated for potential future use in clinical trials due to its storage stability in resource‐limited settings. All adverse events were grade 1 or 2 in severity. Overall, RDV exhibited a linear profile following single‐dose i.v. administration over 2 hours of RDV solution formulation across the dose range of 3–225 mg. Both lyophilized and solution formulations provided comparable PK parameters. High intracellular concentrations of the active triphosphate (~ 220‐fold to 370‐fold higher than the in vitro half‐maximal effective concentration against SARS‐CoV‐2 clinical isolate) were achieved following infusion of 75 mg or 150 mg lyophilized formulation over 30 minutes or 2 hours. Following multiple‐doses of RDV 150 mg once daily for 7 or 14 days, RDV exhibited a PK profile similar to single‐dose administration. Metabolite GS‐441524 accumulated ~ 1.9‐fold after daily dosing. Overall, RDV exhibited favorable safety and PK profiles that supported once‐daily dosing.
Driven by the pressing demand for stable energy systems, zinc−air batteries (ZABs) have emerged as crucial energy storage solutions. However, the quest for cost‐effective catalysts to enhance vital ...oxygen evolution and reduction reactions remains challenging. FeNiCo|MnGaOx heterostructure nanoparticles on carbon nanotubes (CNTs) are synthesized using liquid‐phase reduction and H2 calcination approach. Compared to its component, such FeNiCo|MnGaOx/CNT shows a high synergistic effect, low impedance, and modulated electronic structure, leading to a superior bifunctional catalytic performance with an overpotential of 255 mV at 10 mA cm−2 and half‐wave potential of 0.824 V (ω = 1600 rpm and 0.1 m KOH electrolyte). Moreover, ZABs based on FeNiCo|MnGaOx/CNT demonstrate notable features, including a peak power density of 136.1 mW cm−2, a high specific capacity of 808.3 mAh gZn−1, and outstanding stability throughout >158 h of uninterrupted charge−discharge cycling. Theoretical calculations reveal that the non‐homogeneous interface can introduce more carriers and altered electronic structures to refine intermediate adsorption reactions, especially promoting O* formation, thereby enhancing electrocatalytic performance. This work demonstrates the importance of heterostructure interfacial modulation of electronic structure and enhancement of adsorption capacity in promoting the implementation of OER/ORR, ZABs, and related applications.
FeNiCo|MnGaOx heterostructure nanoparticles on carbon nanotubes (CNTs) is synthesized using liquid‐phase reduction and H2 calcination approach. Compared to its individual component, such FeNiCo|MnGaOx/CNT shows high synergistic effect, low impedance, and modulated electronic structure, leading to superior bifunctional catalytic performance with an over potential of 255 mV at 10 mA cm−2 and half‐wave potential of 0.824V.
Coronary artery disease (CAD) is the leading cause of death worldwide. Long noncoding RNAs (lncRNAs) are a class of noncoding transcripts of > 200 nucleotides and are increasingly recognized as ...playing functional roles in physiology and disease. ANRIL is an lncRNA gene mapped to the chromosome 9p21 genetic locus for CAD identified by the first series of genome-wide association studies (GWAS). However, ANRIL’s role in CAD and the underlying molecular mechanism are unknown. Here, we show that the major ANRIL transcript in endothelial cells (ECs) is DQ485454 with a much higher expression level in ECs than in THP-1 monocytes. Of note, DQ485454 expression was down-regulated in CAD coronary arteries compared with non-CAD arteries. DQ485454 overexpression significantly reduced monocyte adhesion to ECs, transendothelial monocyte migration (TEM), and EC migration, which are critical cellular processes involved in CAD initiation, whereas siRNA-mediated ANRIL knockdown (KD) had the opposite effect. Microarray and follow-up quantitative RT-PCR analyses revealed that the ANRIL KD down-regulated expression of AHNAK2, CLIP1, CXCL11, ENC1, EZR, LYVE1, WASL, and TNFSF10 genes and up-regulated TMEM100 and TMEM106B genes. Mechanistic studies disclosed that overexpression of CLIP1, EZR, and LYVE1 reversed the effects of ANRIL KD on monocyte adhesion to ECs, TEM, and EC migration. These findings indicate that ANRIL regulates EC functions directly related to CAD, supporting the hypothesis that ANRIL is involved in CAD pathogenesis at the 9p21 genetic locus and identifying a molecular mechanism underlying lncRNA-mediated regulation of EC function and CAD development.
The load-bearing capacity of damaged composite materials can be improved using the double adhesive repair technique. This study uses acoustic emission (AE) as the primary detection method to examine ...the damage evolution of modified double-bonded repair specimens and discover the most effective configuration for bi-adhesive repair. The introduction of machine learning and signal feature extraction in the analysis of huge acoustic emission parameters has significantly improved the accuracy and efficiency of damage classification. Following the preliminary division of the clustering results of the unsupervised algorithm, the corresponding relationship between various clustering types and damage types is confirmed using the energy characteristics of wavelet packet decomposition. Parameter and waveform analysis are extensively utilized in studying the AE damage of composite materials and have complementary advantages. Thus, a supervised classifier is established by combining characteristic parameters with time-frequency domain analysis of the signal waveform. Furthermore, machine learning is used to process the large signal set and analyze the debonding damage behavior of the patch. In the end, it is shown that the specimens with the modified adhesive in the middle of the repair area displayed superior repair results. Hence, when combined with machine learning, the signal classification of the damage evolution behavior of repaired specimens is realized with high accuracy.
To develop and evaluate a deep learning model based on chest CT that achieves favorable performance on opportunistic osteoporosis screening using the lumbar 1 + lumbar 2 vertebral bodies fusion ...feature images, and explore the feasibility and effectiveness of the model based on the lumbar 1 vertebral body alone.
The chest CT images of 1048 health check subjects from January 2021 to June were retrospectively collected as the internal dataset (the segmentation model: 548 for training, 100 for tuning and 400 for test. The classification model: 530 for training, 100 for validation and 418 for test set). The subjects were divided into three categories according to the quantitative CT measurements, namely, normal, osteopenia and osteoporosis. First, a deep learning-based segmentation model was constructed, and the dice similarity coefficient(DSC) was used to compare the consistency between the model and manual labelling. Then, two classification models were established, namely, (i) model 1 (fusion feature construction of lumbar vertebral bodies 1 and 2) and (ii) model 2 (feature construction of lumbar 1 alone). Receiver operating characteristic curves were used to evaluate the diagnostic efficacy of the models, and the Delong test was used to compare the areas under the curve.
When the number of images in the training set was 300, the DSC value was 0.951 ± 0.030 in the test set. The results showed that the model 1 diagnosing normal, osteopenia and osteoporosis achieved an AUC of 0.990, 0.952 and 0.980; the model 2 diagnosing normal, osteopenia and osteoporosis achieved an AUC of 0.983, 0.940 and 0.978. The Delong test showed that there was no significant difference in area under the curve (AUC) values between the osteopenia group and osteoporosis group (P = 0.210, 0.546), while the AUC value of normal model 2 was higher than that of model 1 (0.990 vs. 0.983, P = 0.033).
This study proposed a chest CT deep learning model that achieves favorable performance on opportunistic osteoporosis screening using the lumbar 1 + lumbar 2 vertebral bodies fusion feature images. We further constructed the comparable model based on the lumbar 1 vertebra alone which can shorten the scan length, reduce the radiation dose received by patients, and reduce the training cost of technologists.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Objectives
To measure the myocardial extracellular volume (ECV) in patients with heart failure with preserved ejection fraction (HFpEF) using dual-energy computed tomography with late iodine ...enhancement (LIE-DECT) and to evaluate the relationship between ECV and risk of HFpEF and cardiac structure and function.
Methods
A total of 112 consecutive patients with HFpEF and 80 consecutive subjects without heart disease (control group) who underwent LIE-DECT were included. All patients were divided into ischaemic and non-ischaemic groups according to the LIE patterns detected using iodine maps. The ischaemic scar burden was calculated in the ischaemic HFpEF group. Iodine maps and haematocrit were used to measure ECV in the non-ischaemic HFpEF group and remote ECV of the non-scarred myocardium in the ischaemic HFpEF group, respectively. Cardiac structural and functional variables were collected.
Results
ECV in patients with non-ischaemic HFpEF (
n
= 77) and remote ECV in patients with ischaemic HFpEF (
n
= 35) were significantly higher than those in control subjects (
p
< 0.001). Multivariate logistic regression analysis revealed that after adjusting for age, sex, body mass index, smoking, and drinking, a higher ECV/remote ECV was still associated with non-ischaemic HFpEF and ischaemic HFpEF (
p
< 0.001). A positive correlation was established between ECV and cardiac structural and functional variables (
p
< 0.05) in all participants. Subgroup analysis showed that ECV/remote ECV and ischaemic scar burden positively correlated with heart failure classification in the HFpEF subgroup (
p
< 0.05).
Conclusion
ECV/remote ECV elevation was significantly associated with non-ischaemic and ischaemic HFpEF. Remote ECV and LIE may have synergistic effects in the risk assessment of ischaemic HFpEF.
Key Points
•
ECV/remote ECV elevation is associated not only with non-ischaemic HFpEF but also with ischaemic HFpEF.
•
ECV/remote ECV and ischaemic scar burden are correlated with cardiac structure and function
.
Flexible electromagnetic shielding composite material has good deformation ability and stable electromagnetic shielding performance. In this paper, Au@CNT/sodium alginate/polydimethylsiloxane ...flexible composites are prepared by infiltrating PDMS polymer into Au@CNT/sodium alginate sponge skeleton. Nano-scale Au particles coated on CNT surface can effectively improve the electrical conductivity and electromagnetic shielding performance of the composite. The experimental results show that the log function values of conductivity and electromagnetic shielding performance obey a quasi linear relationship. After 10% elastic tensile strain, the conductivity of all samples are remain unchanged, which indicate a stable electromagnetic shielding performance under strain. Combined with the multi-scale model analysis, the mechanism of electrical stability and the effect of Au sizes and cladding rate are discussed. Calculation results show that the electromagnetic shielding performance of the flexible composite sample could reach more than 60 dB. These flexible shielding composites with stable performance under strain may have good application potential, such as for wearable smart electronics.
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