Search

In this study, calibrated hot box and finite element simulation methods were used to study the influence of a slotted web on the thermal performance of a lightweight steel stud composite wall. By comparing the results from the simulations and experiments, the accuracy of the finite element method was verified; this method was then used for parameter analyses. The results showed that the wall's thermal transfer coefficient is inversely proportional to increases in the length of the slot and height of the stud web, leading to improvements in the thermal insulation effect; vice versa, the wall thermal transfer coefficient increases when the slot transverse spacing and stud thickness increase, and the insulation effect correspondingly worsens. The stud spacing influences the insulation performance of the wall by changing the proportion of studs within a certain wall. The greater the proportion of studs, the greater the stud thermal bridging, the faster the thermal loss, and the worse the insulation effect of the wall. In practice, the height of the stud web can be set as required. Preferably, for practical applications, the number of rows of slots is 5–7, the length of the slots is 70–80 mm, the transverse distance of the slots is 6–8 mm, the thickness of each stud is 1 or 1.2 mm, and the distance of each stud is 600 mm. [ABSTRACT FROM AUTHOR]

Sweet potato (Ipomoea batatas [L.] Lam) is an important food crop, an excellent fodder crop, and a new type of industrial raw material crop. The lack of genomic resources could affect the process of industrialization of sweet potato. Few detailed reports have been completed on the mitochondrial genome of sweet potato. In this research, we sequenced and assembled the mitochondrial genome of sweet potato and investigated its substructure. The mitochondrial genome of sweet potato is 270,304 bp with 23 unique core genes and 12 variable genes. We detected 279 pairs of repeat sequences and found that three pairs of direct repeats could mediate the homologous recombination into four independent circular molecules. We identified 70 SSRs in the whole mitochondrial genome of sweet potato. The longest dispersed repeat in mitochondrial genome was a palindromic repeat with a length of 915 bp. The homologous fragments between the chloroplast and mitochondrial genome account for 7.35% of the mitochondrial genome. We also predicted 597 RNA editing sites and found that the rps3 gene was edited 54 times, which occurred most frequently. This study further demonstrates the existence of multiple conformations in sweet potato mitochondrial genomes and provides a theoretical basis for the evolution of higher plants and cytoplasmic male sterility breeding. [ABSTRACT FROM AUTHOR]

Sweet potato (Ipomoea batatas [L.] Lam) is an important food crop, an excellent fodder crop, and a new type of industrial raw material crop. The lack of genomic resources could affect the process of industrialization of sweet potato. Few detailed reports have been completed on the mitochondrial genome of sweet potato. In this research, we sequenced and assembled the mitochondrial genome of sweet potato and investigated its substructure. The mitochondrial genome of sweet potato is 270,304 bp with 23 unique core genes and 12 variable genes. We detected 279 pairs of repeat sequences and found that three pairs of direct repeats could mediate the homologous recombination into four independent circular molecules. We identified 70 SSRs in the whole mitochondrial genome of sweet potato. The longest dispersed repeat in mitochondrial genome was a palindromic repeat with a length of 915 bp. The homologous fragments between the chloroplast and mitochondrial genome account for 7.35% of the mitochondrial genome. We also predicted 597 RNA editing sites and found that the rps3 gene was edited 54 times, which occurred most frequently. This study further demonstrates the existence of multiple conformations in sweet potato mitochondrial genomes and provides a theoretical basis for the evolution of higher plants and cytoplasmic male sterility breeding. [ABSTRACT FROM AUTHOR]

Background: SARS-CoV-2, the causal agent of COVID-19, enters human cells using the ACE2 (angiotensin-converting enzyme 2) protein as a receptor. ACE2 is thus key to the infection and treatment of the coronavirus. ACE2 is highly expressed in the heart and respiratory and gastrointestinal tracts, playing important regulatory roles in the cardiovascular and other biological systems. However, the genetic basis of the ACE2 protein levels is not well understood. Methods: We have conducted the largest genome-wide association meta-analysis of plasma ACE2 levels in >28 000 individuals of the SCALLOP Consortium (Systematic and Combined Analysis of Olink Proteins). We summarize the cross-sectional epidemiological correlates of circulating ACE2. Using the summary statistics–based high-definition likelihood method, we estimate relevant genetic correlations with cardiometabolic phenotypes, COVID-19, and other human complex traits and diseases. We perform causal inference of soluble ACE2 on vascular disease outcomes and COVID-19 severity using mendelian randomization. We also perform in silico functional analysis by integrating with other types of omics data. Results: We identified 10 loci, including 8 novel, capturing 30% of the heritability of the protein. We detected that plasma ACE2 was genetically correlated with vascular diseases, severe COVID-19, and a wide range of human complex diseases and medications. An X-chromosome cis–protein quantitative trait loci–based mendelian randomization analysis suggested a causal effect of elevated ACE2 levels on COVID-19 severity (odds ratio, 1.63 [95% CI, 1.10–2.42]; P =0.01), hospitalization (odds ratio, 1.52 [95% CI, 1.05–2.21]; P =0.03), and infection (odds ratio, 1.60 [95% CI, 1.08–2.37]; P =0.02). Tissue- and cell type–specific transcriptomic and epigenomic analysis revealed that the ACE2 regulatory variants were enriched for DNA methylation sites in blood immune cells. Conclusions: Human plasma ACE2 shares a genetic basis with cardiovascular disease, COVID-19, and other related diseases. The genetic architecture of the ACE2 protein is mapped, providing a useful resource for further biological and clinical studies on this coronavirus receptor. [ABSTRACT FROM AUTHOR]

Harmonic injection method is widely used in the suppression of current harmonic and torque ripple in field-oriented control (FOC) permanent magnet synchronous motor (PMSM) servo system. However, under some working conditions of FOC PMSM, the harmonic injection method fails to suppress the current harmonics and causes oscillation. To analyze the cause of oscillation, the transfer mechanism of injected voltage harmonic is analyzed in this article, and the relation between injected voltage harmonic and current harmonic is derived. The theoretical analysis results show that the relation between harmonics will change with motor speed and parameters of FOC PMSM. When the relation between harmonics is reversed, the existing harmonic injection method will fail and cause harmonic oscillation. To solve this problem, a simple improvement of the harmonic injection method is proposed in this article based on the proposed close-loop model. The correctness of the mathematical derivation and the effectiveness of the proposed method is evaluated by experiment and simulation. [ABSTRACT FROM AUTHOR]

Background: Most of Camellia oleifera forests have low fruit yield and poor oil quality that are largely associated with soil fertility. Soil physical and chemical properties interact with each other affecting soil fertility and C. oleifera growing under different soil conditions produced different yield and oil composition. Three main soil types were studied, and redundancy, correlation, and double-screening stepwise regression analysis were used for exploring the relationships between C. oleifera nutrients uptake and soil physical and chemical properties, shedding light on the transport law of nutrient elements from root, leaves, and kernel, and affecting the regulation of fruit yield and oil composition. Results: In the present study, available soil elements content of C. oleifera forest were mainly regulated by water content, pH value, and total N, P and Fe contents. Seven elements (N, P, K, Mg, Cu, Mn and C) were key for kernel's growth and development, with N, P, K, Cu and Mn contents determining 74.0% the yield traits. The transport characteristics of these nutrients from root, leaves to the kernel had synergistic and antagonistic effects. Increasing oil production and unsaturated fatty acid content can be accomplished in two ways: one through increasing N, P, Mg, and Zn contents of leaves by applying corresponding N, P, Mg, Zn foliar fertilizers, while the other through maintaining proper soil moisture content by applying Zn fertilizer in the surface layer and Mg and Ca fertilizer in deep gully. Conclusion: Soil type controlled nutrient absorption by soil pH, water content and total N, P and Fe content. There were synergistic and antagonistic effects on the inter-organ transport of nutrient elements, ultimately affecting N, P, K, Cu and Mn contents in kernel, which determined the yield and oil composition of C. oleifera. [ABSTRACT FROM AUTHOR]

We will introduce four new geometric constants closely related to the James constant J (X) , which have symmetric structure, along with a discussion on the relationships among them and some other well-known geometric constants via several inequalities, together with the calculation of several values on some specific spaces. In addition, we will characterize geometric properties of J 1 (X) , such as uniform non-squareness and uniformly normal structure. [ABSTRACT FROM AUTHOR]

We will introduce some new geometric constants based on the constant H (X) proposed by Gao and the constant A 2 (X) proposed by M. Baronti et al. We first provide a study of a new constant M 1 (X) closely related to the midlines of equilateral triangles, including a discussion of some of its properties and the connections with other parameters of the sphere. Next, we focus on a new constant M 2 (X) and its generalized form M 2 (X , p , q) , along with some of their basic properties. Finally, we concentrate on a new constant M 3 (X) and discuss some of its properties. [ABSTRACT FROM AUTHOR]

Background: C. Oleifera is among the world's largest four woody plants known for their edible oil production, yet the contribution rate of improved varieties is less than 20%. The species traditional breeding is lengthy cycle (20–30 years), occupation of land resources, high labor cost, and low accuracy and efficiency, which can be enhanced by molecular marker-assisted selection. However, the lack of high-quality molecular markers hinders the species genetic analysis and molecular breeding. Results: Through quantitative traits characterization, genetic diversity assessment, and association studies, we generated a selection population with wide genetic diversity, and identified five excellent high-yield parental combinations associated with four reliable high-yield ISSR markers. Early selection criteria were determined based on kernel fresh weight and cultivated 1-year seedling height, aided by the identification of these 4 ISSR markers. Specific assignment of selected individuals as paternal and maternal parents was made to capitalize on their unique attributes. Conclusions: Our results indicated that molecular markers-assisted breeding can effectively shorten, enhance selection accuracy and efficiency and facilitate the development of a new breeding system for C. oleifera. [ABSTRACT FROM AUTHOR]

The current, torque, and speed harmonics caused by deadtime effect in voltage source inverter (VSI)-fed permanent magnet synchronous motor (PMSM) usually lead to undesired torque ripple and extra electrical loss, etc. In this article, a mathematical model is proposed to predict the deadtime-related harmonics in VSI-fed field-oriented control PMSM, and a deadtime-related harmonic minimization method is proposed based on proportional-integral (PI) controllers tuning and under the premise of keeping the same control strategy. The expressions of current, torque, and speed harmonics caused by deadtime effects are obtained based on the complex amplitude expression of the voltage error harmonic and the derivation of the closed-loop transfer function from the deadtime-related voltage error to the d–q axis current. Based on the derived expressions, optimization objective functions are built to search the optimal PI parameters for minimizing deadtime-related harmonics and reducing the torque ripple. The optimization constraint functions can be adjusted for transient performance requirements, so the transient performance can keep good even if the deadtime-related harmonics are minimized with the optimal PI parameters. Both simulation analysis and experimental data verify the correctness of the analytical prediction and the validity of the deadtime-related harmonic minimization method. [ABSTRACT FROM AUTHOR]

Background. The cell regeneration and blood supply of bone defect lesions are restricted under osteoporotic pathological conditions, which make the healing of bone defect of osteoporosis still a great challenge. The current therapeutic strategies that mainly inhibit bone resorption are not always satisfactory for osteoporotic bone defects, which make the development of new therapies an urgent need. Methods. Previously, we prepared chitosan/nanohydroxyapatite (CS/nHA) biomimetic nanocomposite scaffolds for controlled delivery of bone morphogenetic protein 2-derived peptide (P24). In this study, we determined the effect of coculturing adipose-derived stromal cells (ADSCs) and human umbilical vein endothelial cells (HUVECs) with the CS-P24/nHA nanocomposite scaffolds on osteoporotic bone defect healing. In vitro mixed coculture models were employed to assess the direct effects of coculture. Results. ADSCs cocultured with HUVECs showed significantly greater osteogenic differentiation and mineralization compared with ADSCs or HUVECs alone. The CS-P24/nHA scaffold cocultured with ADSCs and HUVECs was more effective in inducing osteoporotic bone repair, as demonstrated by micro-computed tomography and histology of critical-sized calvariae defects in ovariectomized rats. Calvariae defects treated with the CS-P24/nHA nanocomposite scaffold plus ADSC/HUVEC coculture had a greater area of repair and better reconstitution of osseous structures compared with defects treated with the scaffold plus ADSCs or the scaffold plus HUVECs after 4 and 8 weeks. Conclusion. Taken together, coculture of ADSCs and HUVECs with the CS-P24/nHA nanocomposite scaffold is an effective combination to repair osteoporotic bone defects. [ABSTRACT FROM AUTHOR]

This paper investigates the stability of strong exponential attractors with respect to dissipative index θ ∈ [ 1 / 2 , 1) for the Kirchhoff wave model with structural nonlinear damping: u t t − ϕ (‖ ∇ u ‖ 2) Δ u + σ (‖ ∇ u ‖ 2) (− Δ) θ u t + f (u) = g (x). It proves that for each θ 0 ∈ [ 1 / 2 , 1) , there exists a family of strong bi-space exponential attractors, which are also the standard exponential attractors of optimal regularity and are Hölder continuous at the point θ 0 in the topology of the strong solution space provided that the nonlinearity f (u) is of the optimal subcritical growth. The method used here allows to overcome the difficulties in literatures before to get the Lipschitz continuity and quasi-stability of the evolution semigroup S θ (t) to obtain the desired result. [ABSTRACT FROM AUTHOR]

• A review of the adoption of generative adversarial networks in clinical neuroimaging. • We focus on GAN's applications in modeling disease effects of neurologic diseases. • We discuss the pitfalls of current studies and provide future perspectives. Generative adversarial networks (GANs) are one powerful type of deep learning models that have been successfully utilized in numerous fields. They belong to the broader family of generative methods, which learn to generate realistic data with a probabilistic model by learning distributions from real samples. In the clinical context, GANs have shown enhanced capabilities in capturing spatially complex, nonlinear, and potentially subtle disease effects compared to traditional generative methods. This review critically appraises the existing literature on the applications of GANs in imaging studies of various neurological conditions, including Alzheimer's disease, brain tumors, brain aging, and multiple sclerosis. We provide an intuitive explanation of various GAN methods for each application and further discuss the main challenges, open questions, and promising future directions of leveraging GANs in neuroimaging. We aim to bridge the gap between advanced deep learning methods and neurology research by highlighting how GANs can be leveraged to support clinical decision making and contribute to a better understanding of the structural and functional patterns of brain diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

To improve the uniformity of one‐pixel width and continuity of the thinned edges, this paper proposes an edge thinning algorithm acting on grey‐scale edge images based on 24 self‐defined single‐pixel connection patterns. First, for binary or blurred grey‐scale gradient edge images, a distance–greyscale coupling algorithm is proposed to achieve gradient enhancement in the edge width direction. Then the elimination rules of noise points and gradient calculation method are given. Secondly, the marking rules of the first three pixels of each edge are given. The next pixel to be marked must meet that the new last three pixels belong to the 24 connection modes. Whether the qualified pixels are retained depends on its grey value and the local edge gradient. The algorithm is tested on four types of images. The results show that the proposed method can guarantee uniform, smooth, and connected one‐pixel‐wide lines that lie at the centre of the initial edges. The algorithm and the existing algorithms are performed on portrait image and four scenarios of the indoor datasets. Five evaluation indicators are statistically analyzed to prove the feasibility and effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

• Development of SCFST stub column internally reinforced by CFRP profile. • Axial compression tests on 10 SCFST-CFRP columns and 2 SCFST columns. • Study of mechanical properties of SCFST-CFRP column with varying parameters. • Evaluation of existing design codes of AIJ, EC4, AISC-LRFD, and GB50936. • Development of empirical equations for column axial load capacity. This paper presents experimental and numerical investigations of an innovative composite column, which is formed using a square concrete filled steel tubular (SCFST) column internally reinforced by a carbon fiber reinforced polymer (CFRP) profile (referred to as SCFST-CFRP column), under axial compression. Full-scale axial compression tests were conducted on ten SCFST-CFRP columns with different steel ratios and steel grades and two traditional SCFST columns. The test results, including failure mode, axial load–displacement response, and strain development, were analyzed to examine the column behavior under axial compression. Numerical models of SCFST-CFRP columns were developed and validated to further investigate the stress distribution and load-bearing contribution of each column component. The validated models were then used for parametric studies that evaluated the effects of material and structural parameters on column behavior and axial load capacity. Besides, design rules, as suggested in the codes of AIJ, EC4, AISC-LRFD, and GB50936, were evaluated using experimental and numerical data for axially loaded SCFST-CFRP columns. In addition, empirical equations were developed through unified criteria to predict the SCFST-CFRP column capacity under axial compression. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a type of arthritis that causes joint pain and limited mobility. In recent years, some studies have shown that the pathological process of OA chondrocytes is related to ferroptosis. Our study aims to identify and validate differentially expressed ferroptosis-related genes (DEFRGs) in OA chondrocytes and to investigate the potential molecular mechanisms. RNA-sequencing and microarray datasets were downloaded from Gene Expression Omnibus (GEO) data repository. Differentially expressed genes (DEGs) were screened by four methods: limma-voom, edgeR, DESeq2, and Wilcoxon rank-sum test. Weighted correlation network analysis (WGCNA), protein-protein interactions (PPI), and cytoHubba of Cytoscape were applied to identify hub genes. Clinical OA cartilage specimens were collected for quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis, western blotting (WB), histological staining, transmission electron microscopy (TEM), and transfection. Sankey diagram was used to visualize the relationships between the expression level of SLC3A2 in the damaged area and clinical factors. Based on bioinformatics analysis, clinical factors, and experiment validation, SLC3A2 was identified as a hub gene. It was down-regulated in OA cartilage compared to normal cartilage (p < 0.05). Functional enrichment analysis revealed that SLC3A2 was associated with ferroptosis-related functions. Spearman correlation analysis showed that the expression level of SLC3A2 in the OA cartilage-damaged area was closely related to BMI, obesity grade, and Kellgren-Lawrence grade. Furthermore, in vitro experiments validated that SLC3A2 inhibited ferroptosis and suppressed cartilage degeneration in OA. In summary, we demonstrated that SLC3A2 inhibited ferroptosis and suppressed cartilage degeneration in OA. These findings provide a new idea for the study of the pathogenesis of OA, thus providing new means for the clinical diagnosis and targeted therapy of OA. [ABSTRACT FROM AUTHOR]

Introduction: The histopathology grading system is the gold standard post-operative method to evaluate cartilage degeneration in knee osteoarthritis (OA). Magnetic resonance imaging (MRI) T1 rho/T2 mapping imaging can be used for preoperative detection. An association between histopathology and T1 rho/T2 mapping relaxation times was suggested in previous research. However, the cutoff point was not determined among different histopathology grades. Our study aimed to determine the cutoff point of T1 rho/T2 mapping.Material and methods: T1 rho/T2 mapping images were acquired from 80 samples before total knee replacements. Then the histopathology grading system was applied.Results: The mean T1 rho/T2 mapping relaxation times of 80 samples were 39.17 ms and 37.98 ms respectively. Significant differences were found in T1 rho/T2 mapping values between early-stage and advanced OA (p < 0.001). The cutoff point for T1 rho was 33 ms with a sensitivity of 94.12 (95% CI: 80-99.3) and a specificity of 91.30 (95% CI: 79.2-97.6). The cutoff point for T2 mapping was suggested as 35.04 ms with a sensitivity of 88.24 (95% CI: 72.5-96.7) and specificity of 97.83 (95% CI: 88.5-99.9). After bootstrap simulation, the 95% CI of the T1 rho/T2 mapping cutoff point was estimated as 29.36 to 36.32 ms and 34.8 to 35.04 ms respectively. The area under the PR curve of T1 rho/T2 mapping was 0.972 (95% CI: 0.925-0.992) and 0.949 (95% CI: 0.877-0.989) respectively.Conclusions: The cutoff point of T1 rho relaxation times, which was suggested as 33 ms, could be used to distinguish early-stage and advanced OA. [ABSTRACT FROM AUTHOR]

Understanding the thermal transport in polymer-bonded explosives (PBXs) is critical for enhancing the safety and reliability during PBX design, especially in the absence of effective experimental measurements. In this work, we rigorously investigated the phonon properties of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and polyvinylidene fluoride (PVDF) and calculated the interfacial thermal conductance using an ab initio approach. The diffuse mismatch model and anharmonic inelastic model were adopted to examine the interfacial thermal conductance as a function of temperature for the TATB–PVDF interface. Our calculation results indicate that low-frequency phonon modes and the two-phonon process play dominant roles in the thermal transport at interfaces. In contrast, high-order phonon processes involving three to eight phonons accounted for around 8% of the interfacial thermal conductance at the TATB–PVDF interface. Phonon properties, such as the velocity and degree of phonon density overlap, are discussed for the TATB–PVDF and 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX)–PVDF interfaces to estimate the interfacial thermal conductance of PBXs. This study provides a theoretical explanation for the establishment of a research method for PBX thermal transport. [ABSTRACT FROM AUTHOR]

In the abrasive belt grinding process, actual material removal is an important parameter that affects its accuracy. At present, for obtaining the actual material removal, offline measurements are required to establish the mathematical prediction model. To improve the accuracy and efficiency of abrasive belt machine grinding, this paper proposes a novel method for monitoring material removal using multiple sensors and a two-dimensional (2D) convolutional neural network (2D-CNN) learning algorithm. In this method, features of multiple types (color, texture, and shape) are extracted from vision signals, and that of multiple domains (time, frequency, and time–frequency domain) are extracted from sound and tactile signals. These features are constructed into a 2D feature matrix as the input model, and the 2D-CNN prediction model is established between the multisensor features and the material removal rate of the abrasive belt grinding process. An experimental dataset is used to train and verify the established model. The results show that the proposed method can identify that sensor signals are sensitive to the material removal rate. After optimizing and tuning the model parameters, the coefficient of determination of the prediction results is as high as 94.5% and the root mean square error is 0.017. Therefore, the proposed method can be employed for the prediction of material removal rate for different belt specifications and different grinding parameters. Compared to traditional machine learning methods, this method can yield better training results without feature selection and optimization. [ABSTRACT FROM AUTHOR]

• Conducted eccentric compression tests on 18 CFSST-CFRP long column. • Investigated eccentrically loaded behavior and resistance of CFSST-CFRP column. • Evaluated effects of slenderness ratios and load eccentricity ratio. • Analyzed load bearing capacity and load-transferring mechanism. • Performed parametric studies on column bearing capacity. • Developed design equations to predict ultimate eccentric load capacity. This study investigated behavior of concrete filled square steel tubular (CFSST) columns encased with I-shaped CFPR under eccentric compression. Full-scale eccentric compression tests were conducted on eighteen column specimens consisting of square steel tube, concrete, and an I-shaped CFRP profile. The test program considered effects of load eccentricity ratio and column slenderness ratio. The eccentrically loaded column behavior was investigated with respect to the mid-height deflection, load, and failure modes. The development and distribution of longitudinal strain and neural axis for the column were also studied. Finite element models were developed and validated against tested results to further analyze the load-transferring mechanism of the composite column and perform detailed parametric studies. The results indicated that the CFSST column encased with I-shaped CFRP behaved in a ductile manner with the improved capacity and increased stability. Finally, design equations were developed using tested and simulated data to estimate ultimate bearing capacity of the CFSST column encased with I-shaped CFRP when subjected to eccentric compression. The predicted column capacities using the design equations matched well with the tested and simulated capacities. [ABSTRACT FROM AUTHOR]

• High-strength CFSST stub column with an encased I-shaped CFRP profile was proposed. • Axial compression test was performed on HCFHSST-CFRP stub column. • Investigated effects of material strengths and steel ratio on column behavior. • The combinations of high-strength materials and CFRP improved column resistance. • Formulas were proposed to predict ultimate axial load capacity. A new composite column that consists of high-strength square steel tube, high-strength concrete, and carbon fiber reinforced polymer (CFRP) profile with a I-shaped cross section was developed and investigated in this study. This paper experimentally and numerically investigated axially loaded behavior of high-strength concrete filled high-strength steel tubular (HCFHSST) stub column with an encased I-shaped CFRP profile. In the experimental study, axial compression tests were completed on eight specimens to examine the axial load response of the composite column, including the load–displacement curves, failure mode, and strain distribution. Finite element models of the composite column were developed using ABAQUS and validated by comparing numerical results with experimental data. The validated models were used to further investigate the load sharing and transferring mechanism for each component of the composite column. Results showed that the composite column comprehensively used the advantageous merits of concrete, steel tube, and CFRP as a unit to share the applied load at different loading stages: linearly elastic, elastic–plastic, hardening, post-peak descending, and residual plateau stage. Parametric studies were performed that assessed influences of critical design parameters on the axially loaded behavior of the stub column. The examined parameters included the compressive strength of high-strength concrete, yield strength of high-strength steel, and steel ratio. Finally, empirical equations were proposed to determine the ultimate vertical strain and the ultimate axial load capacity of the HCFHSST stub column encased with a I-shaped CFRP profile. [ABSTRACT FROM AUTHOR]

[Display omitted] • Theoretical simulation was employed to select suitable conductive polymers for coating. • Three HMX/conductive polymer based composites were facilely prepared by in-situ polymerization. • The synergistic desensitization of impact and electrostatic spark was obtained. • Improved thermal phase stability with sluggish phase-transition kinetics was confirmed. Safety performance under external stimuli plays a crucial role for energetic materials. Therefore, desensitization of high explosive arouses widespread research interests in the field of energetic materials. Nevertheless, synergistically reducing impact and electrostatic spark sensitivities of 1,3,5,7-tetranittro-1,3,5,7-tetrazocane (HMX) remains challenging. Herein, a novel strategy concerning conductive polymer coating was proposed to solve this issue. Theoretically, the polypyrrole (PPy) can form a complete shell and strong interaction with HMX crystals. The HMX@PPy composite has been successfully achieved by in-situ polymerization, exhibiting superior sensitivities (impact: from 7 J to 27.5 J and electrostatic spark: from 0.4 J to 1.68 J) among reported HMX-based energetic materials. In addition, the thermal phase stability of HMX can also be visibly improved with sluggish phase-transition kinetics by introducing PPy coating. The current study provides a design concept for high energy explosives with low sensitivity and improved comprehensive performances. [ABSTRACT FROM AUTHOR]

Purpose. To identify the molecular etiology of a Chinese family with nonsyndromic macular dystrophy. Methods. Ophthalmic examinations were performed, and genomic DNA was extracted from available family members. Whole exome sequencing of two members (the proband and her unaffected mother) and Sanger sequencing in available family members were performed to screen potential pathogenic variants. Results. Novel compound heterozygous variants, c.1066C>T (p.Pro356Ser) and c.1102+2T>C, in the major facilitator superfamily domain containing 8 gene (MFSD8) were suspected to be involved in this family's macular dystrophy phenotype. The novel c.1066C>T variant in the MFSD8 gene probably resulted in substitution of serine for proline at the 356th residue and was predicted to be "uncertain significance" through in silico analyses. The novel c.1102+2T>C variant in the MFSD8 gene was likely to affect the splicing form and predicted to be "pathogenic." Conclusion. The novel compound heterozygous variants, c.1066C>T (p.Pro356Ser) and c.1102+2T>C, in the MFSD8 gene are likely responsible for the isolated macular dystrophy phenotype in this family. This study enlarged the MFSD8 gene mutant spectrum and might provide more accurate genetic counseling for this family. [ABSTRACT FROM AUTHOR]

• Fly ash and costless seawater are used to sequester CO 2 at ambient conditions. • High carbonation efficiency of up to 94.8% is obtained. • The carbonation efficiency increased with the solid/liquid and the CO 2 flow rate. • The absorbed CO 2 is converted to aragonite. • The low pH range of 8.2 ∼ 10.4 may be the key to the high carbonation efficiency. Direct CO 2 mineralization using fly ash is a promising technology to achieve CO 2 sequestration. Seawater's abundance and calcium-rich composition make it an attractive substitute solution for CO 2 sequestration. However, there have been limited studies conducted so far, and the mineralization mechanism remains unclear, which has constrained its industrial application potential. Here we utilized low CaO-content fly ash in combination with seawater to perform direct CO 2 mineralization under ambient conditions, achieving a remarkable carbonation efficiency of 94.8 %. Upon scrutinizing the carbonate parameter evolution, we identify a crucial pH range (8.2 ∼ 10.4) that enhances calcium elution efficiency, leading to heightened carbonation efficiency. The involvement of Mg(OH) 2 within this pH range influences CaCO 3 precipitation kinetics and crystalline phase. This innovative approach holds promise for carbon sequestration and presents a valuable contribution to sustainable CO 2 utilization strategies. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. However, the AD mechanism has not yet been fully elucidated to date, hindering the development of effective therapies. In our work, we perform a brain imaging genomics study to link genetics, single-cell gene expression data, tissue-specific gene expression data, brain imaging-derived volumetric endophenotypes, and disease diagnosis to discover potential underlying neurobiological pathways for AD. To do so, we perform brain-wide genome-wide colocalization analyses to integrate multidimensional imaging genomic biobank data. Specifically, we use (1) the individual-level imputed genotyping data and magnetic resonance imaging (MRI) data from the UK Biobank, (2) the summary statistics of the genome-wide association study (GWAS) from multiple European ancestry cohorts, and (3) the tissue-specific cis-expression quantitative trait loci (cis-eQTL) summary statistics from the GTEx project. We apply a Bayes factor colocalization framework and mediation analysis to these multi-modal imaging genomic data. As a result, we derive the brain regional level GWAS summary statistics for 145 brain regions with 482,831 single nucleotide polymorphisms (SNPs) followed by posthoc functional annotations. Our analysis yields the discovery of a potential AD causal pathway from a systems biology perspective: the SNP chr10:124165615:G>A (rs6585827) mutation upregulates the expression of BTBD16 gene in oligodendrocytes, a specialized glial cells, in the brain cortex, leading to a reduced risk of volumetric loss in the entorhinal cortex, resulting in the protective effect on AD. We substantiate our findings with multiple evidence from existing imaging, genetic and genomic studies in AD literature. Our study connects genetics, molecular and cellular signatures, regional brain morphologic endophenotypes, and AD diagnosis, providing new insights into the mechanistic understanding of the disease. Our findings can provide valuable guidance for subsequent therapeutic target identification and drug discovery in AD. [ABSTRACT FROM AUTHOR]

Dislocation climb plays an important role in understanding plastic deformation of metallic materials at high temperature. In this paper, we present a continuum formulation for dislocation climb velocity based on densities of dislocations. The obtained continuum formulation is an accurate approximation of the Green's function-based discrete dislocation dynamics method (Gu et al., 2015). The continuum dislocation climb formulation has the advantage of accounting for both the long-range effect of vacancy bulk diffusion and that of the Peach–Koehler climb force, and the two long-range effects are canceled into a short-range effect (integral with fast-decaying kernel) and in some special cases, a completely local effect. This significantly simplifies the calculation in the Green's function-based discrete dislocation dynamics method, in which a linear system has to be solved over the entire system for the long-range effect of vacancy diffusion and the long-range Peach–Koehler climb force has to be calculated. This obtained continuum dislocation climb velocity can be applied in any available continuum dislocation dynamics frameworks. We also present numerical validations for this continuum climb velocity and simulation examples for implementation in continuum dislocation dynamics frameworks. • We developed a continuum formulation based on dislocation densities, as an accurate approximation of the Green's function-based discrete dislocation dynamics method. • The continuum formulation accounts for both the long-range effect of vacancy bulk diffusion and that of the Peach–Koehler climb force, and the two long-range effects are canceled into a short-range effect (integral with fast-decaying kernel) and in some special cases, a completely local effect. • The continuum formulation has also been generalized to include the pipe diffusion-assisted self-climb based on the discrete self-climb dislocation dynamics model. • The obtained continuum dislocation climb velocity formulation can be applied in any available continuum dislocation dynamics frameworks. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zirconium tungstate was used to tailor thermal expansion of energetic composites. • Coefficient of thermal expansion was greatly reduced by only 5% ZrW 2 O 8 as filler. • Thermal shock resistance of modified composite was found to be 45% lifted. • Depressed CTE was beneficial to the safety and reliability of the weapon system. • New insight is provided for building customized thermal expansion composite. Due to their large positive thermal expansion property, polymer bonded explosives (PBXs) are prone to deform under environmental temperature cycle. Based on the volume compensation effect, zirconium tungstate (ZrW 2 O 8) with a negative thermal expansion (NTE) characteristic was first introduced to tailor the thermal expansion of energetic composites in this work. The PBXs modified with ZrW 2 O 8 were fabricated by non-water kneading granulation technique, and their thermal expansion, mechanical properties, as well as microstructural thermal stability were systematically investigated. The coefficient of thermal expansion (CTE) during the heating stage and the strain were reduced by 19.8% and 19.1% for modified PBXs with the incorporation of 10 wt% ZrW 2 O 8. For ZrW 2 O 8 filled energetic composites at lower filler loading (≤10 wt%), the experimental values fell in between the Turner's model and Schapery's lower boundaries. Numerical simulation revealed that the decreased CTE could reduce thermal stress, which would benefit the safety and reliability of the weapon system. Combined with thermal and mechanical analyses, the thermal shock resistance of the ZrW 2 O 8 modified energetic composite with 10 wt% filler loading was found to be 45% higher than that of pristine PBX without ZrW 2 O 8 , suggesting a reinforcement effect, which would be helpful for long-term storage of materials under environmental temperature cycles. The successful application of this functional NTE system to energetic materials might provide a new strategy for the construction of novel energetic composites with tailored thermal expansion. [ABSTRACT FROM AUTHOR]

The interfacial interaction and the microstructure evolution play a vital role in the mechanical properties of thermoplastic polyurethane (TPU) based energetic composites. In this work, inspired by the strong adhesion of mussels, 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) energetic crystals were coated with polydopamine (PDA) via in-situ polymerization of dopamine and then dispersed in TPU matrix. The core-shell structure of CL-20@PDA was confirmed by in-depth structural characterizations. The uniform and compact PDA shell gave rise to a high thermal stability with phase transition temperature of CL-20 crystals increased by 11.5 °C. Moreover, the PDA modification endowed the TPU based composites with excellent mechanical properties. A striking increase in mechanical properties and creep resistance was achieved with 6 h polymerization time of PDA. Compared with the PBX-Raw with untreated CL-20 crystals, the compressive and tensile strength after PDA coating increased by 115% and 57%, and the compressive and tensile fracture energy increased by 148% and 68%. The storage modulus at 25 °C was 40% higher than PBX-Raw. The enhancement effectivity could be ascribed to both interfacial interaction and the microstructure evolution of TPU binder. The theoretical simulations by molecular dynamics demonstrated the strong interfacial interaction mechanism between CL-20 and PDA. Moreover, the abundant hydrogen bonds between the hard segments of TPU and functional groups of PDA facilitated the formation of more hard microdomains which acted as physical crosslinking points to promote the phase separation. This work provides a potential method for the mechanical and thermal enhancement for TPU based energetic materials based on dopamine chemistry. Inspired by the strong chemical adhesion of mussels, the polymerization of dopamine was introduced to coat energetic crystals, which play a vital role in the interfacial interaction and the microstructure evolution of thermoplastic polyurethane (TPU) binder, resulted in mechanical and thermal enhancement for TPU based energetic materials. [Display omitted] • Core-shell structure was constructed through a novel, facile and general route via self-polymerization of dopamine. • CL-20@PDA composites exhibited 11.5 °C higher phase transition (ε.→γ) temperature than that of pure CL-20. • The mechanical enhancement was disclosed based on interfacial interaction and the microstructure evolution of TPU binder. • Theoretical simulations for the interfacial interaction showed good accordance with the experimental observations. [ABSTRACT FROM AUTHOR]

The diabetic wound is easily to develop into a chronic wound because of the extremely serious and complex inflammatory microenvironment including biofilm formation, over-expressed reactive oxygen species (ROS), hypoxia and insufficiency of nitric oxide (NO) synthesis. In this work, a multifunctional hydrogel was designed and prepared by crosslinking hydrophilic poly(PEGMA- co -GMA- co -AAm) (PPGA) polymers with hyperbranched poly-L-lysine (HBPL)-modified manganese dioxide (MnO 2) nanozymes. Pravastatin sodium, which is supposed to participate in the synthesis of NO, was further loaded to obtain the HMP hydrogel. The capabilities of this hydrogel in scavenging different types of ROS, generating O 2 , killing broad spectrum bacteria, and protecting cells against oxidative stress were confirmed in vitro. The transcriptome analysis revealed that HBPL inhibited bacterial quorum sensing (QS) system, downregulated virulent genes, and interfered bacterial metabolism. The HBPL-crosslinked hydrogels killed up to 94.1%–99.5% of methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli (E. coli) and Pseudomonas aeruginosa even at 109 CFU/mL. HBPL modification greatly increased the stability of MnO 2 nanosheets in physiological environment. The MRSA-caused infection was effectively treated by the HBPL-crosslinked HMP hydrogel in vivo , and thereby the wound closure at inflammatory phase was promoted significantly. The treatment of HMP hydrogel reduced the ROS degree and relieved the inflammatory level significantly, accompanied by the decreased neutrophil infiltration and enhanced M2-type macrophage polarization in vivo. Significantly lower levels of inflammatory factors such as interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α) and chemokines-1 (CXCL-1), and higher levels of anti-inflammatory cytokines such as IL-4 and IL-10 were also confirmed. Moreover, the HMP hydrogel could promote the secretion of transforming growth factor-β (TGF-β) and stimulate neovascularization, and deposition of collagen with a thicker skin and epithelium structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • An antibacterial ROS-scavenging hydrogel is developed to treat skin infected wounds. • The hyper-branched poly-L-lysine (HBPL) is a kind of antimicrobial peptides. • The HBPL blocks quorum sensing and interferes with bacterial metabolism. • The HBPL reduces bacterial virulence and inhibits biofilm formation. • The hydrogel suppresses inflammation, promotes scarless healing of skin wounds. Staphylococcus aureus (S. aureus) is the most common pathogen causing skin and soft tissue infections. The emergence and spread of methicillin-resistant S. aureus (MRSA) pose a major challenge for the treatment of infected wounds because of its high resistance and enhanced virulence. The overexpression of reactive oxygen species (ROS) at the site of skin wounds also exacerbates inflammation, leading to slower healing and severe scarring. Therefore, comprehensive strategy against MRSA-infected wounds is needed in clinical practice. Interference with quorum sensing (QS), a process of bacterial cell-to-cell chemical communication, has been considered a promising strategy to reduce the virulence and pathogenicity of MRSA. Herein, we designed a ROS-scavenging hydrogel loaded with a type of bacterial QS inhibitor, hyper-branched poly-L-lysine (HBPL), which has efficient bactericidal ability against planktonic and biofilm-embedded MRSA. We found that this multifunction hydrogel showed excellent anti-oxidative effects against different types of ROS, and it could inhibit the QS system, metabolic activity, and bacterial virulence. In vivo, the ROS-scavenging HBPL hydrogel efficiently accelerated the healing of MRSA-infected full-thickness skin defect by blocking QS, killing bacteria, suppressing inflammation, and promoting angiogenesis. Together, our results offer a new insight for scarless healing of MRSA-infected cutaneous wounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • One-step surface fluorination of n-Al was achieved by chemical decorating of PDA coating with organic fluoride. • Contact area between reactive components was optimized owing to high coating uniformity and strong interfacial strength. • Generation of abundant fluoride gas upon ignition facilitated the mass transport and self-activation of Al particles. • Remarkably improved combustion performance were realized for the core–shell structured composites. • Rational design of interfacial structure and diffusion distance for adjustable reaction kinetics. Surface composition plays a crucial role for the energy output performance of nanosized aluminum (n-Al) based metallic fuels. However, effective surface modification strategy with integrated functions and mild preparation conditions remains being exploited. Herein, a polydopamine fluoride (PF) coating was successfully constructed by covalent decoration of polydopamine (PDA) with thiol-terminated organic fluoride for surface engineering of n-Al under ambient conditions. The uniform coating of PF shell on the n-Al surface enabled the Al@PF composites optimized contact area between reactive components (Al and F). Concomitantly, the generation of fluoride gaseous species from PF coating facilitated the mass transport and self-activation of n-Al particles. It resulted in a substantially enhanced burning rate (196.4 mm s−1), which is 8.1 and 3.6 times than that of pristine n-Al (24.2 mm s−1) and physically mixed samples (54.7 mm s−1), respectively. Additionally, the reaction kinetics could be readily adjusted by tailoring the diffusion distance of reactants, as exhibited by varied heat release (0.24–1.43 kJ g−1), ignition delay (79–427 ms), and pressurization rate (6.3 × 101–2.3 × 103 kPa s−1). On this basis, the surface reaction mechanism was further clarified by combining theoretical simulation and experimental results. The current study provided a general approach for improving combustion performance and modulating reaction kinetics of advanced energy materials by elaborate surface design. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene/Aluminum (PTFE/Al) composite with high energy density and combustion reaction performance has received widespread attention in the field of propellants, explosives, and pyrotechnics. In order to precisely control combustion reaction and energy output performance, gradient structured PTFE/Al composite (mass and diameter gradient) has been designed and constructed through 3D printing technology. PTFE/Al ink is prepared by acoustic resonance mixing to control rheological properties (viscosity and modulus) for 3D printing technology. The largest reaction heat (7749.95 J/g) and burning rate (~130 mm/s) are achieved for gradient lines with diameter of 2.42 mm and mass ratio of 60:40 (PTFE/Al). Moreover, the progressive change from steady combustion to deflagration containing three stages of pressure output is observed for gradient structured PTFE/Al cylinder. This work reveals that gradient structure could provide new strategy to tune energy output and combustion performances, which can promote the practical application of PTFE/Al reactive materials. [ABSTRACT FROM AUTHOR]

Polymer bonded explosives (PBXs) have weak strength and toughness, as well as they are prone to fracture under stress. To overcome these disadvantages, inspired by the strong adhesion of mussels and the hierarchical structure of nacre, we designed and fabricated novel PBX composites by coating three explosive crystals (2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105; 1,3,5-triamino-2,4,6-trinitrobenzene, TATB; and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane, HMX) with polydopamine (PDA), respectively. The results of mechanical analysis and in situ small angle neutron scattering measurements showed that these novel PBX composites exhibited higher strength, stronger toughness, and higher creep resistance, and higher microstructural thermal stability simultaneously, compared to PBXs without multiple bio-inspired designs. Contact angles measurements indicated that the interfacial interaction intensities between energetic crystals and polymer binder could be largely enhanced by PDA coating on energetic crystals. Theoretical calculations revealed that PDA-modified PBX-LLM-105 achieved the most increment in mechanical strength, which were well consistent with the experiments. An enhancement mechanism combining the van der Waals forces, π–π interaction, and hydrogen bonds, as well as surface roughness was proposed to account for the variety of mechanical properties and microstructural thermal stability of PDA-modified PBXs. The results revealed in this study are commonly significant to interfacial modification and performance enhancement of materials. [Display omitted] • Multiple bio-inspired designs were applied successfully to balance the strength and toughness ofPBXs. • The bio-inspired designs have significantly enhanced the mechanical strength, creep resistance, and thermal stability of PBXs. • The molecular structures and surface roughness of energetic materials have great effect on the interfacial interaction. • The inter-facial interaction enhancement mechanism of polydopamine on different explosive crystals were detailedly revealed. [ABSTRACT FROM AUTHOR]