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The composite modified double-base propellants (CMDB) were experimentally investigated for mechanical behavior under wide tension strain rate loading from 0.0001 s−1 to 2500 s−1, based on Instron mechanical machine and modified Hopkinson tension bar technique. Stress-strain curves were obtained for its strain rate effect and integrality evaluation. The results indicated that CMDB presents high rate-dependence with flow stress distinctly increase as loading strain rate increasing. A succinct constitutive formulation is established with only five parameters, to characterize well the rate-dependence and strain hardening behavior. The fracture morphologies were investigated by scanning electron microscopy, and it is indicated that they are also rate-dependent: the cavitation and matrix damage induced from matrix deformation work less but more RDX particles fractures with strain rate increasing. Equivalent unit cell model with brittle cracking was established to simulate the mechanical behavior and failure characteristics of CMDB. The results reveal that with increasing loading strain rates, CMDB presents a tough-brittle transition, with less cavitation and matrix damage induced by matrix deformation, while more RDX particles fracture. Series of simulated results confirm qualitatively the experimental observations, and the obtained stress contours facilitate to validate the observed characteristics and propose reasonable mechanisms.

Abstract Cell motility plays an essential role in many biological processes as cells move and interact within their local microenvironments. Current methods for quantifying cell motility typically involve tracking individual cells over time, but the results are often presented as averaged values across cell populations. While informative, these ensemble approaches have limitations in assessing cellular heterogeneity and identifying generalizable patterns of single‐cell behaviors, at baseline and in response to perturbations. In this study, CaMI is introduced, a computational framework designed to leverage the single‐cell nature of motility data. CaMI identifies and classifies distinct spatio‐temporal behaviors of individual cells, enabling robust classification of single‐cell motility patterns in a large dataset (n = 74 253 cells). This framework allows quantification of spatial and temporal heterogeneities, determination of single‐cell motility behaviors across various biological conditions and provides a visualization scheme for direct interpretation of dynamic cell behaviors. Importantly, CaMI reveals insights that conventional cell motility analyses may overlook, showcasing its utility in uncovering robust biological insights. Together, a multivariate framework is presented to classify emergent patterns of single‐cell motility, emphasizing the critical role of cellular heterogeneity in shaping cell behaviors across populations.

Nanorubber/epoxy composites containing 0, 2, 6 and 10 ​wt% nanorubber are subjected to uniaxial compression over a wide range of strain rate from 8 ​× ​10−4 s−1 to ∼2 ​× ​104 s−1. Unexpectedly, their strain rate sensitivity and strain hardening index increase with increasing nanorubber content. Potential mechanisms are proposed based on numerical simulations using a unit cell model. An increase in the strain rate sensitivity with increasing nanorubber content results from the fact that the nanorubber becomes less incompressible at high strain, generating a higher hydro-static pressure. Adiabatic shear localization starts to occur in the epoxy under a strain rate of 22,000 s−1 when the strain exceeds 0.35. The presence of nanorubber in the epoxy reduces adiabatic shear localization by preventing it from propagating.

A special microenvironment called the “pre-metastatic niche” is thought to help primary tumor cells migrate to new tissues and invade them, in part because the normal barrier function of the vascular endothelium is compromised. While the primary tumor itself can promote the creation of such niches by secreting pro-metastatic factors, the underlying molecular mechanisms are still poorly understood. Here, we show that the injection of primary tumor-secreted pro-metastatic factors from B16F10 melanoma or 4T1 breast cancer cells into healthy mice can induce the destruction of the vascular endothelial glycocalyx, which is a polysaccharide coating on the vascular endothelial lumen that normally inhibits tumor cell passage into and out of the circulation. However, when human umbilical vein endothelial cultures were treated in vitro with these secreted pro-metastatic factors, no significant destruction of the glycocalyx was observed, implying that this destruction requires a complex in vivo microenvironment. The tissue section analysis revealed that secreted pro-metastatic factors could clearly upregulate macrophage-related molecules such as CD11b and tumor necrosis factor-α (TNF-α) in the heart, liver, spleen, lung, and kidney, which is associated with the upregulation and activation of heparanase. In addition, macrophage depletion significantly attenuated the degradation of the vascular endothelial glycocalyx induced by secreted pro-metastatic factors. This indicates that the secreted pro-metastatic factors that destroy the vascular endothelial glycocalyx rely primarily on macrophages. Our findings suggest that the formation of pre-metastatic niches involves degradation of the vascular endothelial glycocalyx, which may hence be a useful target for developing therapies to inhibit cancer metastasis.

Abstract The high-affinity K+ transporter (HAK) family plays a vital role in K+ uptake and transport as well as in salt and drought stress responses. In the present study, we identified 22 HAK genes in each Medicago truncatula and Medicago sativa genome. Phylogenetic analysis suggested that these HAK proteins could be divided into four clades, and the members of the same subgroup share similar gene structure and conserved motifs. Many cis-acting elements related with defense and stress were found in their promoter region. In addition, gene expression profiles analyzed with genechip and transcriptome data showed that these HAK genes exhibited distinct expression pattern in different tissues, and in response to salt and drought treatments. Furthermore, co-expression analysis showed that 6 homologous HAK hub gene pairs involved in direct network interactions. RT-qPCR verified that the expression level of six HAK gene pairs was induced by NaCl and mannitol treatment to different extents. In particular, MtHK2/7/12 from M. truncatula and MsHAK2/6/7 from M. sativa were highly induced. The expression level of MsHAK1/2/11 determined by RT-qPCR showed significantly positive correlation with transcriptome data. In conclusion, our study shows that HAK genes play a key role in response to various abiotic stresses in Medicago, and the highly inducible candidate HAK genes could be used for further functional studies and molecular breeding in Medicago.

Polymers, extensively used in aerospace and transport industries, mostly present distinct strain rate dependent. Their mechanical behaviors under dynamic loading conditions have not been well characterized by succinct formulations for practical engineering. In this work, the mechanical behaviors of a representative epoxy are investigated under strain rates from 0.001 s−1 to 5100 s−1 using Instron 5848 and split Hopkinson bar apparatus, for its constitutive behaviors and efficient formulation to characterize their multi-mechanical behaviors. The materials present high rate-dependence and share similar mechanical behaviors under wide strain rates including multiple characteristics: peak stress followed by post-yielding stress softening, plateau stress and strain hardening. The results from the strain-controlled experiments facilitate to analyze the damage degradation after peak stress formulated by a modified Weibull model. A succinct constitutive model containing only eight parameters is then constructed with three parallel components: Weibull model, Maxwell model and power function, which can capture well the multi-mechanical characteristics. It is easily further extended to other polymer and composites from literatures with stronger characterization capacity by less parameters.

Medicago falcata L. is an important legume forage grass with strong drought resistant, which could be utilized as an important gene pool in molecular breed of forage grass. In this study, M. falcata seedlings were treated with 400 mM mannitol to simulate drought stress, and the morphological and physiological changes were investigated, as well as the transcriptome changes of M. falcata seedlings at different treatment time points (0 h, 2 h, 6 h, 12 h, 24 h, 36 h and 48 h). Transcriptome analyses revealed four modules were closely related with drought response in M. falcata by WGCNA analysis, and four ERF transcription factor genes related with drought stress were identified (MfERF053, MfERF9, MfERF034 and MfRAP2.1). Among them, MfERF053 was highly expressed in roots, and MfERF053 protein showed transcriptional activation activity by transient expression in tobacco leaves. Overexpression of MfERF053 in Arabidopsis improved root growth, number of lateral roots and fresh weight under drought, salt stress and exogenous ABA treatments. Transgenic Arabidopsis over-expressing MfERF053 gene grew significantly better than the wild type under both drought stress and salt stress when grown in soil. Taken together, our strategy with transcriptome combined WGCNA analyses identified key transcription factor genes from M. falcata, and the selected MfERF053 gene was verified to be able to enhance drought and salt resistance when over-expressed in Arabidopsis.

Hopkinson bar loading technique needs theoretical instruction for desired stress waves, to achieve controllable deformation under constant high strain rate loading, for it is the indispensable access while investigating material's rate-dependence and deformation mechanism under transient loading. In this work, theoretical and experimental studies are focused on the involved issues. Firstly, the theoretical deduction based on stress wave theory is performed for constant true strain rate loading, and the equation is formulated of an ideal incident strain wave for different materials. The formulated waves are further clarified by case studies of specimens with various mechanical behaviors, and they are found to present concave characteristics under large deformation. Secondly, an efficient methodology is proposed for single stress wave loading, and the target requirement is deduced theoretically. It is easily achieved experimentally by performing specific strain-controlled experiments: prior to and beyond peak stress of epoxy. Finally, some methods are proposed for achieving the formulated stress waves, and experimental verifications are also conducted on various materials.

Galega officinalis L. is a perennial herb of the Fabaceae family. The flowers of G. officinalis L. are colorful and suitable for ornamental purposes. It can be used as a food complement for animals and humans, and it could promote lactation in animals and humans. In this study, we obtained the complete chloroplast genome of G. officinalis L. and found it is 125,086 bp in length. The GC content of this genome is 34.18%. Among the 112 unique genes in the chloroplast genome of G. officinalis L., 30 tRNA, 4 rRNA and 78 protein-coding genes were successfully annotated. We constructed the maximum likelihood (ML) tree with 26 species, and concluded that G. officinalis is phylogenetically closely related to the genus of Cicer, Glycine and Desmodium.

Growth Regulatory Factors (GRF) are plant-specific transcription factors that play critical roles in plant growth and development as well as plant tolerance against stress. In this study, a total of 16 GRF genes were identified from the genomes of Medicago truncatula and Medicago sativa. Multiple sequence alignment analysis showed that all these members contain conserved QLQ and WRC domains. Phylogenetic analysis suggested that these GRF proteins could be classified into five clusters. The GRF genes showed similar exon–intron organizations and similar architectures in their conserved motifs. Many stress-related cis-acting elements were found in their promoter region, and most of them were related to drought and defense response. In addition, analyses on microarray and transcriptome data indicated that these GRF genes exhibited distinct expression patterns in various tissues or in response to drought and salt treatments. In particular, qPCR results showed that the expression levels of gene pairs MtGRF2–MsGRF2 and MtGRF6–MsGRF6 were significantly increased under NaCl and mannitol treatments, indicating that they are most likely involved in salt and drought stress tolerance. Collectively, our study is valuable for further investigation on the function of GRF genes in Medicago and for the exploration of GRF genes in the molecular breeding of highly resistant M. sativa.

Nuclear factor YB (NF-YB) are plant-specific transcription factors that play a critical regulatory role in plant growth and development as well as in plant resistance against various stresses. In this study, a total of 49 NF-YB genes were identified from the genomes of Medicago truncatula and Medicago sativa. Multiple sequence alignment analysis showed that all of these NF-YB members contain DNA binding domain, NF-YA interaction domain and NF-YC interaction domain. Phylogenetic analysis suggested that these NF-YB proteins could be classified into five distinct clusters. We also analyzed the exon–intron organizations and conserved motifs of these NF-YB genes and their deduced proteins. We also found many stress-related cis-acting elements in their promoter region. In addition, analyses on genechip for M. truncatula and transcriptome data for M. sativa indicated that these NF-YB genes exhibited a distinct expression pattern in various tissues; many of these could be induced by drought and/or salt treatments. In particular, RT-qPCR analysis revealed that the expression levels of gene pairs MsNF-YB27/MtNF-YB15 and MsNF-YB28/MtNF-YB16 were significantly up-regulated under NaCl and mannitol treatments, indicating that they are most likely involved in salt and drought stress response. Taken together, our study on NF-YB family genes in Medicago is valuable for their functional characterization, as well as for the application of NF-YB genes in genetic breeding for high-yield and high-resistance alfalfa.

Agropyron pectinatum is a perennial forage widely cultivated in China, and it belongs to the Gramineous family. In this study, we assembled the complete chloroplast genome of A. pectinatum. The whole chloroplast genome of A. pectinatum is 135,041 bp in length, comprising a pair of inverted repeat (IR) regions (20,821 bp) that are separated by a large single copy (LSC) region (80,632 bp) and a small single copy (SSC) region (12,767 bp). The chloroplast genome of A. pectinatum contains 133 genes, and 87 of them are protein-coding genes, 38 are tRNA, and eight are rRNA genes. The chloroplast genome of A. pectinatum could provide valuable information for varieties identification and evolution of the Agropyron Gaertn.

Aquaporins (AQP) are distributed ubiquitously in plants, and they play important roles in multiple aspects of plant growth and development, as well as in plant resistance to various environmental stresses. In this study, 43 MsAQP genes were identified in the forage crop Medicago sativa. All the MsAQP proteins were clustered into four subfamilies based on sequence similarity and phylogenetic relationship, including 17 TIPs, 14 NIPs, 9 PIPs and 3 SIPs. Analyses of gene structure and conserved domains indicated that the majority of the deduced MsAQP proteins contained the signature transmembrane domains and the NPA motifs. Analyses on cis-acting elements in the promoter region of MsAQP genes revealed the presence of multiple and diverse stress-responsive and hormone-responsive cis-acting elements. In addition, by analyzing the available and comprehensive gene expression data of M. truncatula, we screened ten representative MtAQP genes that were responsive to NaCl or drought stress. By analyzing the sequence similarity and phylogenetic relationship, we finally identified the corresponding ten salt- or drought-responsive AQP genes in M. sativa, including three MsTIPs, three MsPIPs and four MsNIPs. The qPCRs showed that the relative expression levels of these ten selected MsAQP genes responded differently to NaCl or drought treatment in M. sativa. Gene expression patterns showed that most MsAQP genes were preferentially expressed in roots or in leaves, which may reflect their tissue-specific functions associated with development. Our results lay an important foundation for the future characterization of the functions of MsAQP genes, and provide candidate genes for stress resistance improvement through genetic breeding in M. sativa.

Alopecurus pratensis L. is one of the most important fodder grasses distributed in sub-frigid regions of the world. In this study, the complete chloroplast genome of A. pratensis was deciphered and is 136,157 bp in length. The genome includes a large single-copy region of 80,275 bp, small single-copy region of 12,830 bp, and a pair of inverted repeat regions of 21,526 bp. The GC content of the complete chloroplast genome of A. pratensis is 38.30%. Among the 134 unique genes in the circular genome, 38 tRNA, eight rRNA, and 88 protein-coding genes were annotated. We constructed the Maximum likelihood (ML) tree with 13 species from the Poaceae and found that A. pratensis was phylogenetically related to A. arundinaceus. The published A. pratensis chloroplast genome will provide useful information for phylogenetic and evolutionary study of the genus Alopecurus in the Poaceae.

Bromus biebersteinii is a perennial gramineous grass, which is mainly distributed in Southwest Asia. In our study, we obtained the complete chloroplast genome of B. biebersteinii and found it is 137,189 bp in length. The GC content of its whole chloroplast genome is 38.37%. Among the 134 unique genes in the circular genome, 38 tRNA, 8 rRNA and 88 protein-coding genes were successfully annotated. We constructed the Maximum likelihood (ML) tree with 12 species, and found that B. biebersteinii was phylogenetically close to Bromus vulgaris of the genus Bromus.

Agropyron desertorum is one of the most important fodder grasses which distributes in the temperate regions of the world. In this study, the complete chloroplast genome of A. desertorum was sequenced. The genome was 135,459 bp in length, with a large single-copy region of 79,617 bp, a small single-copy region of 12,760 bp, and two inverted repeat regions of 21,541 bp. The genome consisted of 132 genes, including 86 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. The GC contents was 38.32%. We constructed the Maximum likelihood (ML) tree with 13 species from the Hordeinae genus, and concluded that A. desertorum was closely related to plant species of the Elymus genus in the phylogenetic tree.

Plant β-galactosidases (BGAL) function in various cell wall biogeneses and modifications, and they belong to the glycoside hydrolase family. However, the roles of BGAL family members in Medicago truncatula cell wall remodeling remain unclear. In this study, a total of 25 MtBGAL members of the glycoside hydrolase gene family 35 were identified, and they were clustered into nine sub-families. Many cis-acting elements possibly related to MeJA and abscisic acid responses were identified in the promoter region of the MtBGAL genes. Transcript analyses showed that these MtBGAL genes exhibited distinct expression patterns in various tissues and developing stem internodes. Furthermore, a stem-specific expression module associated with cell wall metabolic pathways was identified by weighted correlation network analysis (WGCNA). In particular, MtBGAL1 and MtBGAL23 within the stem-specific expression module were highly expressed in mature stems. In addition, several genes involved in lignin, cellulose, hemicellulose and pectin pathways were co-expressed with MtBGAL1 and MtBGAL23. It was also found that MtBGAL1 and MtBGAL23 were localized to the cell wall at the subcellular level, indicating their roles in the modification of cell wall metabolites in Medicago. As a whole, these results will be useful for further functional characterization and utilization of BGAL genes in cell wall modifications aiming to improve the quality of legume forage crops.

The calcineurin B-like protein (CBL) and CBL-interacting protein kinase (CIPK) play important roles in plant signal transduction and response to abiotic stress. Plants of Medicago genus contain many important forages, and their growth is often affected by a variety of abiotic stresses. However, studies on the CBL and CIPK family member and their function are rare in Medicago. In this study, a total of 23 CBL and 58 CIPK genes were identified from the genome of Medicago sativa as an important forage crop, and Medicaog truncatula as the model plant. Phylogenetic analysis suggested that these CBL and CIPK genes could be classified into five and seven groups, respectively. Moreover, these genes/proteins showed diverse exon-intron organizations, architectures of conserved protein motifs. Many stress-related cis-acting elements were found in their promoter region. In addition, transcriptional analyses showed that these CBL and CIPK genes exhibited distinct expression patterns in various tissues, and in response to drought, salt, and abscisic acid treatments. In particular, the expression levels of MtCIPK2 (MsCIPK3), MtCIPK17 (MsCIPK11), and MtCIPK18 (MsCIPK12) were significantly increased under PEG, NaCl, and ABA treatments. Collectively, our study suggested that CBL and CIPK genes play crucial roles in response to various abiotic stresses in Medicago.

This paper studies the effect of the standardization of the strategy translation process on procedural fairness in budgeting and firm performance. Analysis of 250 valid questionnaires using a structural equation model shows that the strategy translation process (STP) affects firm performance not only directly but also indirectly, through budget participation and procedural fairness in budgeting. This study enriches the literature on the economic consequences of strategic performance measurement systems and expands research on procedural fairness in budgeting and the factors influencing firm performance. This study shows that the standard translation and implementation of strategy will decrease managers’ bias in the target-setting process, thus increasing manager’s sense of fairness in the budget process and ultimately improving firm performance.