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To avoid wrinkling and cross-sectional distortion in thin-walled tube bending, a novel bending process called tube press bending under gas internal pressure (abbreviated as TGPB) is proposed. In the TGPB process, internal pressure serves a supportive function and generates an additional tensile stress, which can reduce the axial compressive stress on the inner side of the bend, avoiding the occurrence of wrinkles and cross-sectional distortions. Compared with the previous tube bending technologies, the support pressure inside the tube will not change suddenly with the volume change of the tube cavity due to the compressibility of gas. It is suitable for thin-walled tube bending with large, variable axial curvatures and high strength as the shape of the target part is determined by the die cavity. A theoretical prediction model of critical support pressure for TGPB without wrinkling defects is established. The critical support pressure, wall thickness, and section distortion of tubes with different curvatures bent by TGPB are analyzed through FE simulations and experiments, and tubes with different material properties are also done through FE simulations. The results indicate that the tube can be stably bent to the desired shape under the predicted critical support pressure, which is significantly affected by the bending radius and material characteristics, increases with strength coefficient, and decreases with bending radius and strain hardening exponent. A high-strength steel prebending part with complex variable axial curvatures has been successfully formed by TGPB technology under a support pressure of 5 MPa; the minimum and maximum bending radii of which are 846 mm and 2373 mm, respectively. [ABSTRACT FROM AUTHOR]

Experimental flow stress–strain data under different stress states are often used to calibrate the plastic constitutive model of anisotropic metal materials or identify the appropriate model that is able to reproduce their plastic deformation behavior. Since the experimental stress–strain data are discrete, they need to be mathematically returned to a continuous function to be used to describe an equivalent hardening increment. However, the regression results obtained using existing regression models are not always accurate, especially for stress–strain curves under biaxial stress loading conditions. Therefore, a new regression model is proposed in this paper. The highest-order term in the recommended form of the new model is quadratic, so the functional relationships between stress–strain components can be organized into explicit expressions. All the experimental data of the uniform deformation stage can be substituted into the new model to reasonably reproduce the biaxial experimental stress–strain data. The regression results of experimental data show that the regression accuracy of the new model is greatly improved, and the residual square sum SSE of the regression curves of the new model reduced to less than 50% of the existing three models. The regression results of stress–strain curves show significant differences in describing the yield and plastic flow characteristics of anisotropic metal materials, indicating that accurate regression results are crucial for accurately describing the anisotropic yielding and plastic flow behaviors of anisotropic metal materials. [ABSTRACT FROM AUTHOR]

The simple shear test shows significant advantages when measuring the hardening and shear properties of thin sheet metal at large strains. However, previous shear tests had an end effect caused by local stress concentration and a boundary effect caused by deformation overflow, resulting in non-uniform strain distribution in the shear zone. Therefore, a unique V-shaped double-shear-zone specimen is proposed to measure the Bauschinger effect under cyclic shear loading conditions in this paper. Simple shear experiments and three different types of cycle shear experiments are conducted to analyze the uniformity of deformation in the shear zone and the effect of pre-strain and the number of cyclic loads on the Bauschinger effect of Q890 high-strength steel sheets. The results indicate that the proposed V-shaped double-shear-zone specimen can still maintain uniform shear deformation in forward/reverse cyclic loading experiments, even at large strains. Q890 high-strength steel exhibits a significant Bauschinger effect, which is more pronounced with the increase in shear pre-strain and loading cycles. The results of this paper provide a new approach for studying the hardening characteristics under large strain and the mechanical properties under cyclic shear loading for metal sheets. [ABSTRACT FROM AUTHOR]

We propose an experimental method to identify anisotropic coefficients in non-principal axis directions of thin-walled tubes. The method involves extracting specimens from the parent tubes and machining a hole in the axial center. The specimens are then inserted into a tube without a hole. The inner diameter of the specimen is theoretically equal to the outer diameter of the inner tube. The double-layer tube undergoes free bulging under internal pressure in our self-developed experimental equipment, with the hole on the specimen expanding simultaneously. The stress states around the hole are uniaxial, and the hole deformation can reflect the anisotropic plastic flow characteristics of the tube. Furthermore, based on the information obtained from the proposed experimental method, a hybrid numerical–experimental method was used to identify the anisotropic coefficients of tubes. Through FE simulations, the relationships between the thickness, stress, and strain states around the hole, the hole shape, and anisotropic coefficients of non-principal axis directions are revealed, and the factors that affect the hole deformation are analyzed. Finally, the hole bulging experiments and FE simulations of AA6061-O extruded tube were conducted, and modeled with Hill48 and calibrated by uniaxial tensile and hoop tensile tests. Its in-plane anisotropy coefficients in any direction are given for the first time which first increase and then decrease from 0° to 90°, reaching a maximum of 1.13 in 60° and a minimum of 0.69 in 0°. This work can provide the key experimental data for establishing an accurate anisotropic plastic constitutive model of thin-walled tubes. [ABSTRACT FROM AUTHOR]

To meet the requirement of lighter weight and better performance in tube hydroforming, one of the most important tasks is to accurately predict the forming limit of thin-walled tubes under nonlinear loading paths. This work established the M-K+DF2012 model, a combination of the M-K model and the DF2012 ductile fracture criterion, for the forming limit prediction of thin-walled tubes under nonlinear loading paths. In this model, the failure of the groove is determined by the DF2012 criterion, and the corresponding strains in the uniform region are the limit strains. The limit strains of an AA6061 aluminum alloy tube under a set of linear loading paths and two typical nonlinear loading paths were tested. Parameter values of the M-K+DF2012 model for the tube were determined based on the experimental limit strains under linear loading paths, and the limit strains under the two nonlinear loading paths were predicted. Then the strain-based forming limit diagram (ε-FLD) and the polar effective plastic strain FLD (PEPS-FLD) of the tube under different pre-strains were predicted and discussed. The results show that the limit strains of the tube are obviously path-dependent, and the M-K+DF2012 model can reasonably capture the limit strains of the tube under both linear and nonlinear loading paths. The predicted ε-FLD shows a strong dependence on the pre-strain, while the predicted PEPS-FLD is weakly strain path-dependent and almost path-independent on the right-hand side for the AA6061 tube. [ABSTRACT FROM AUTHOR]

In sheet metal forming, the material is usually subjected to a complex nonlinear loading process, and the anisotropic hardening behavior of the material must be considered in order to accurately predict the deformation of the sheet. In recent years, the homogeneous anisotropic hardening (HAH) model has been applied in the simulation of sheet metal forming. However, the existing HAH model is established in the second-order stress deviator space, which makes the calculation complicated and costly, especially for a plane stress problem such as sheet metal forming. In an attempt to reduce the computational cost, an HAH model in plane stress state is proposed, and called the HAH-2d model in this paper. In the HAH-2d model, both the stress vector and microstructure vector contain only three in-plane components, so the calculation is significantly simplified. The characteristics of the model under typical nonlinear loading paths are analyzed. Additionally, the feasibility of the model is verified by the stress–strain responses of DP780 and EDDQ steel sheets under different two-step uniaxial tension tests. The results show that the HAH-2d model can reasonably reflect the Bauschinger effect and the permanent softening effect in reverse loading, and the latent hardening effect in cross loading, while the predictive accuracy for cross-loading softening remains to be improved. In the future, the HAH-2d model can be further modified to describe more anisotropic hardening behaviors and applied to numerical simulations. [ABSTRACT FROM AUTHOR]

Research investigating the effects and underlying mechanisms of mindfulness on cognitive functioning has accelerated exponentially over the past two decades. Despite the rapid growth of the literature and its influential role in garnering public interest in mindfulness, inconsistent methods in defining and measuring mindfulness have yielded variable findings, which contribute to the overall dearth of clear generalizable conclusions. The focus of this article is to address the lack of cohesion in the collective methodologies used in this domain by providing a new perspective grounded in classic cognitive and experimental psychology principles. We leverage the concept of converging operations to demonstrate how seemingly disparate research strategies can be integrated towards a more unified and systematic approach. An organizing taxonomic framework is described to provide useful structure in how mindfulness can be operationalized, measured, and investigated. We illustrate the rationale and core organizing principles of the framework through a selective review of studies on mindfulness and cognitive control. We then demonstrate the utility of the approach by showing how it can be applied to synthesize extant methodologies and guide the development of future research. Specific suggestions and examples pertaining to experimental design and statistical analysis are provided. [ABSTRACT FROM AUTHOR]

The natural populations of lactic acid bacteria (LAB) and silage quality of pineapple residue silage were investigated in this study. A total of 34 LAB strains originally isolated from pineapple residue silage were characterized and identified by phenotypic and genotypic methods. These LAB strains were Gram-positive and catalase-negative bacteria, which were divided into four groups: Lactiplantibacillusplantarum (52.9%), Levilactobacillus brevis (14.7%), Lacticaseibacillus paracasei (17.6%) and Leuconostoc citreum (14.7%). Lactiplantibacillus plantarum was the dominant species. Homofermentative strains accounted for 70.5%. After 30 days of ensiling, the pineapple residue silage could be well preserved with low pH value (3.65) and high content of lactic acid (75.57 g/kg of DM). In this study, LAB populations of pineapple residue silage fermentation were investigated, which indicated that pineapple residue silage was a potential good animal feed source. In addition, this result will be valuable for screening-appropriate inoculants aimed at improving the quality. [ABSTRACT FROM AUTHOR]

BACKGROUND Feed shortage is a factor restricting animal production in the tropics, therefore how to use natural woody plant resources as animal feed is an important strategy. RESULTS: Under the dual stress of an anaerobic and acidic environment, the microbial response during the fermentation of paper mulberry (PM) silage was found to be sensitive. The Gram‐negative bacteria and mould died, and the dominant microbial community rapidly shifted to Gram‐positive bacteria, resulting in a large reduction in microbial diversity and abundance. Exogenous bran additives interfered with the stress effects of the woody silage environment. Wheat bran (WB) accelerated the response of microorganisms to the anaerobic stress, and lactic acid bacteria became the dominant microbial community, thereby enhancing the lactic acid fermentation of silage, affecting the metabolic pathways of microorganisms, and improving the flavour and quality of the silage. Addition of rice bran made Enterobacter and Clostridium species quickly respond to the stress of the silage environment and become the predominant bacterial groups. In particular, anaerobic and spore‐forming Clostridium species showed a strong tolerance to the silage environment, leading to butyric acid fermentation and protein degradation of the silage, and reducing its fermentation quality. CONCLUSION: The PacBio single‐molecule real‐time (SMRT) sequencing technology accurately revealed the microbial co‐occurrence network and fermentation mechanism of silage. Our results indicate that PM can be used in combination with WB to prepare high‐quality silage for animal production. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Over the past two decades, scientific interest in understanding the relationship between mindfulness and cognition has accelerated. However, despite considerable investigative efforts, pervasive methodological inconsistencies within the literature preclude a thorough understanding of whether or how mindfulness influences core cognitive functions. The purpose of the current study is to provide an initial “proof-of-concept” demonstration of a new research strategy and methodological approach designed to address previous limitations. Specifically, we implemented a novel fully within-subject state induction protocol to elucidate the neurobehavioral influence of discrete mindfulness states—focused attention (FA) and open monitoring (OM), compared against an active control—on well-established behavioral and ERP indices of executive attention and error monitoring assessed during the Eriksen flanker task. Bayesian mixed modeling was used to test preregistered hypotheses pertaining to FA and OM effects on flanker interference, the stimulus-locked P3, and the response-locked ERN and Pe. Results yielded strong but unexpected evidence that OM selectively produced a more cautious and intentional response style, characterized by higher accuracy, slower RTs, and reduced P3 amplitude. Follow-up exploratory analyses revealed that trait mindfulness moderated the influence of OM, such that individuals with greater trait mindfulness responded more cautiously and exhibited higher trial accuracy and smaller P3s. Neither FA nor OM modulated the ERN or Pe. Taken together, our findings support the promise of our approach, demonstrating that theoretically distinct mindfulness states are functionally dissociable among mindfulness-naive participants and that interactive variability associated with different operational facets of mindfulness (i.e., state vs. trait) can be modeled directly. [ABSTRACT FROM AUTHOR]

Simple Summary: Straw has poor palatability, a high degree of lignification, and difficulty in compression, which limits its feed application. Expansion technology can make the hard straw soft and improve the physical and chemical properties of the straw. At present, there is no comprehensive characterization and evaluation of the physical and chemical properties and feed utilization value of expanded straw, and there is a lack of research on the texture properties of straw itself. The texture properties have important effects on the compressibility of straw during silage, the palatability during feeding, and even the energy conversion efficiency during digestion, which have important guiding significance for the further utilization of straw. We combined mechanical and chemical methods to investigate the hardness, elasticity, chewiness, compressive properties, and structural changes of expanded straw and verified the effect of the changes in mechanical properties and chemical structure of expanded straw on improving digestibility by in vitro digestion. This result is of great significance for the further effective application of expanded straw as a feed resource. The hard texture and poor palatability of straw are important factors that hinder its application in feed. Expansion is a technology that can improve the utilization of biomass, but few studies have comprehensively revealed how to change physicochemical characteristics to improve nutritional value. In this study, mechanical and chemical methods were combined to study the texture properties, rheological properties, and physicochemical structures of straw, and its utilization value was evaluated by in vitro rumen digestion. Expansion caused hemicellulose degradation, cellulose separation, and lignin redistribution, resulting in a decrease in crystallinity. The hardness and chewiness of expanded straw were reduced by 55% to 66%, significantly improving palatability. The compressive stress could be reduced by 54–73%, and the relaxation elasticity was reduced by 5% when expanded straw was compressed. The compression deformation of expanded straw was doubled compared to feedstock, and the compacting degree was improved. Expanded straw significantly improved digestibility and gas production efficiency, which was due to the pore structure increasing the attachment of rumen microorganisms; besides that, the reduction of the internal structural force of the straw reduced energy consumption during digestion. The lignin content decreased by 10%, the hardness decreased further in secondary expansion, but the digestibility did not improve significantly. [ABSTRACT FROM AUTHOR]

Mindfulness is frequently associated with improved attention. However, the nature of the relationship between mindfulness and executive attention, a core function of the attentional system, is surprisingly unclear. Studies employing behavioral measures of executive attention have been equivocal. Although neuroscientific studies have yielded more consistent findings, reporting functional and structural changes in executive attention brain regions, the observed changes in brain activity have not been linked to behavioral performance. The current study aimed to fill these gaps in the literature by examining the extent to which trait mindfulness related to behavioral and neurophysiological (indexed by the stimulus-locked P3) measures of executive attention. Results revealed that higher trait mindfulness was related to less flanker interference on accuracy and reaction time, consistent with enhanced executive attention. Critically, mediational analyses showed that the P3 accounted for the relationship between trait mindfulness and executive attention performance, elucidating a neural mechanism through which mindfulness enhances executive attention. [ABSTRACT FROM AUTHOR]

The aim of the current review is to advance the hypothesis that change in self-referential processing is a key but under-examined mechanism through which mindfulness training confers its therapeutic benefits for individuals with internalizing disorders. Consequently, we integrated neuroscientific studies on aberrant self-referential processing in internalizing disorders with contemplative science scholarship examining the effects of mindfulness training on the self-referential system. Reviewing these literatures yielded four major conclusions: (1) internalizing disorders can be characterized by excessive self-referential processing and emotion dysregulation; (2) mindfulness training has moderate effects on reducing internalizing symptoms; (3) mindfulness training promotes the shifting from narrative self-focus to present-centered experiential awareness; (4) such mindfulness-induced changes in self-reference is accompanied by reduced activation in overactive self-referential brain regions that have been implicated in internalizing disorders. Clinical and research implications related to delineating the role of self-referential processing in producing the therapeutic effects of mindfulness training are discussed. [ABSTRACT FROM AUTHOR]

In this study, waterborne polyurethane acrylate (WPUA)/MXene nanocomposite films with varying MXene loadings were fabricated using UV-curing technology, where MXene (Ti3C2Tx) was employed as a nanofiller. The microstructure and chemical structure of the WPUA/MXene nanocomposite films were examined by XRD and FTIR, respectively. The water contact angle testing demonstrated that the incorporation of MXene into the nanocomposite films led to an increase in their hydrophilic properties. The tensile strength, the elongation at break, and Young's modulus of the WPUA/MXene nanocomposite coatings exhibited an initial increase followed by a decrease with increasing MXene loadings. Compared to the pure WPUA film, the tensile strength and elongation at break of nanocomposites with 0.077 wt% MXene loading reached their maximum values, which increased by 39.9% and 38.5%, respectively. Furthermore, the glass transition temperature and the thermal stability were both enhanced by MXene to some extent. This study introduces a novel method for utilizing MXene in UV-curable waterborne coatings. [ABSTRACT FROM AUTHOR]

To overcome the difficulties, such as pollution, low heating efficiency, and complex heating control, in ultra-thick plate forming, a new forming technology was put forward, named as resistance heating forming technology (RHF). Experiment and finite element analysis were conducted to investigate the practicability and the advantages of RHF. The difference in temperature field between RHF and traditional flame heating forming technology (FHF) was discussed in detail. Then, the forming mechanism of RHF was illustrated deeply. The results show that the high temperature zone of resistance heating is of Π shape compared to Λ shape in flame heating method, the nominal width increased by 47.2 %, and the area of heated zone increased by 34.7 %. These result a higher energy utility for RHF. Under the similar energy input, the angular deformation of RHF is bigger than that of FHF, the relative displacement increased by 41.6 %, the angular deformation increased by 20.8 %. Both the experiment and simulation results show that RHF is an attractive and practical technology for ultra-thick plate forming. [ABSTRACT FROM AUTHOR]

Anxious apprehension/worry is associated with exaggerated error monitoring; however, the precise mechanisms underlying this relationship remain unclear. The current study tested the hypothesis that the worry-error monitoring relationship involves left-lateralized linguistic brain activity by examining the relationship between worry and error monitoring, indexed by the error-related negativity (ERN), as a function of hand of error (Experiment 1) and stimulus orientation (Experiment 2). Results revealed that worry was exclusively related to the ERN on right-handed errors committed by the linguistically dominant left hemisphere. Moreover, the right-hand ERN-worry relationship emerged only when stimuli were presented horizontally (known to activate verbal processes) but not vertically. Together, these findings suggest that the worry-ERN relationship involves left hemisphere verbal processing, elucidating a potential mechanism to explain error monitoring abnormalities in anxiety. Implications for theory and practice are discussed. [ABSTRACT FROM AUTHOR]

Any of a theoretical constitutive model all needs to be characterized by proper experimental stress–strain relations to describe material behaviors in the domain of plastic deformation. It means that regression of experimental data by a suitable equation would be the most fundamental work. Some empirical equations currently used in engineering cannot always reproduce experimental stress–strain relations acceptably, particularly for experiments dealing with complex stress states and multi-experimental stress–strain relations. To improve the accuracy of numerical analysis, two new constitutive models for regression of various experimental stress–strain relations are suggested. One is simple relatively to another, but the complex one can give a more accurate reproduction of experimental stress–strain relation. Several uniaxial tensions of rolled sheet metals and a hydro-bulging test have been performed. Regressions of these experimental stress–strain relations have been done by two suggested models. Predicting precisions are discussed and compared with power functions. In relation to the uniaxial tension in different loading direction to the rolling, changeable ratios of transverse to through thickness strain-increments are explained, and their influence on the profile of plastic potential is presented. [ABSTRACT FROM AUTHOR]

Abstract: For a Jeffcott rotor system with a 45° slant crack on the shaft, the motion equations are established with four directions, i.e. two transversal directions, one torsional direction and one longitudinal direction. It can be seen from the deducing process of the stiffness with the strain energy release approach that there are coupling stiffnesses of bending–torsion, bending–tension and torsion–tension for the slant-cracked shaft and only bending–tension for the transverse-cracked one. The paper shows that besides the coupling stiffnesses, there is bending–torsion coupling caused by the eccentricity. All these couplings affect the responses of the slant-cracked shaft and the transverse-cracked one. Comparing responses of a cracked shaft with an open crack model and those with a breathing crack model finds that there are the same prominent characteristic frequencies for these two kinds of shafts, even though the cracked shaft with a breathing crack model behaves much more non-linear than that with an open crack model. Therefore, almost all studies in this paper adopt the open crack model since it needs taking much longer time to compute responses of a breathing cracked shaft than that of an open cracked shaft. Analyses of steady responses indicate that the combined frequencies of the rotating speed and the torsional excitation in the transversal response and the frequency of the torsional excitation in the longitudinal response can be used to detect the slant crack on the shaft of the rotor system. [Copyright &y& Elsevier]

Flexural vibrations of a rotor system with transverse or slant crack are analyzed under torsional excitation by numerical simulation and experiment. Numerical results show that combination frequencies of the rotating speed and the torsional excitation frequency are prominent in the flexural responses of a slant-cracked rotor, but too weak to be identified for a transverse-cracked rotor. In order to verify the results, an experimental setup is installed to simulate the cracked rotor system and a special structure is designed to exert the torsional excitation on the cracked rotor. The experimental results present almost identical characteristic features about the combination frequencies to the numerical results. The numerical and experimental investigations demonstrate these features can be used to distinguish between the transverse crack and the slant crack on the shaft of a rotor system. [Copyright &y& Elsevier]

The deformation behavior and mechanical properties of ZBHO x ceramic (ZrB 2 based ceramics with different amounts of (HfO 2 + 2 vol% CaO), x = 10 - 25 vol%) have been investigated. The results demonstrated that the flow stress of ZBHO x ceramic decreased with an increase in the (HfO 2 +2 vol% CaO) addition at the same strain rate. The flow stress decreased from ∼178 MPa for ZBHO 10 to ∼13 MPa for ZBHO 20 at 1700 °C and a strain rate of 2 × 10−4 s−1, representing a reduction of an order of magnitude. The intergranular deformation twinning and the amorphous phase contribute to the grain boundary sliding and grain rotation of the boride matrix grains, resulting in a significant reduction in flow stress. The matrix grains orientations on the P face (the face perpendicular to the extrusion direction) primarily tend to be along the {0001} plane, while that on the V face (the face parallel to the extrusion direction) tend to be along the {-12-10} plane or {01–10} plane. The textured ZBHO x ceramics exhibit distinct mechanical anisotropy because of the significant orientation difference in the microstructure. The hardness of textured ZBHO x ceramics on V face is higher than that on P face. And the fracture toughness of ZBHOx ceramics exhibits anisotropy on the V face, the fracture toughness in the V-o direction (the direction perpendicular to the P face) is higher than that in V-p direction (the direction parallel to the P face) of ZBHO x ceramics. The intergranular oxide twins synergistically collaborate with the grain rotation within the boride matrix, fostering favorable conditions for texture development. Besides that, the amorphous phase at the interface, characterized by a substantial presence of vacancies and defects, functions as a source of vacancies that facilitates diffusion deformation along the grain boundaries. Simultaneously, the emergence of an amorphous phase at grain boundaries or triple grain junctions further enhances grain boundary sliding and grain rotation of ZrB 2 and B 4 ZrHf grains. [Display omitted] • Mechanically anisotropic textured ZrB 2 ceramics were successfully prepared through the sintering-forging method. • By controlling the content of (HfO 2 +2 vol% CaO), the flow stress of ZrB 2 can be reduced by an order of magnitude. • The formation of oxide twins and amorphous phase facilitate grain boundary sliding and grain rotation of ZrB 2 grains. [ABSTRACT FROM AUTHOR]

The Al 2 O 3 /ZrO 2 (Y 2 O 3) eutectics were prepared by the melt-grown and seeding melt-grown methods, two non-directional solidification methods. We identify the three-dimensional morphology and crystallographic orientations of the Al 2 O 3 /ZrO 2 (Y 2 O 3) eutectics using the focused ion beam milling with electron backscattered diffraction and the transmission electron microscopy. The results show that in the colony, there are three parts of the ZrO 2 (Y 2 O 3) phase composed of interconnected three-level rods. The crystallographic orientation of the colony axis is variable, but the growth directions of the rods show a commonality, < 2 ̅ 0 2 1 > A , in the Al 2 O 3 / ZrO 2 (Y 2 O 3) eutectics, which has been also clarified by the interface structure analysis. The analysis of the preferred growth orientation not only enlightens the growth mechanism of Al 2 O 3 /ZrO 2 (Y 2 O 3) eutectics but also provides a method for the design of novel eutectics. [ABSTRACT FROM AUTHOR]

Large-dimension complex integral thin-shell components are widely used in advanced transportation equipment. However, with the dimensional limitations of raw blanks and the manufacturing process, there are inhomogeneous geometric and mechanical properties at welded joints after welding, which have a significant effect on the subsequent forming process. Therefore, in this paper, the microstructure of welded joints with a sharp property change was accurately characterized by the proposed isothermal treatment method using the BR1500HS welded tube as an example. In addition, an accurate constitutive model of welded tubes was established to predict the deformation behavior. Firstly, the heat-treated specimens were subjected to uniaxial tensile tests and the stress–strain curves under different heat treatment conditions were obtained. Then, the continuous change in flow stress in the direction of the base metal zone, the heat-affected zone and the weld zone was described by the relationship between the microhardness, flow stress and center angle of the welded tube. Using such a method, a continuous constitutive model of welded tubes has been established. Finally, the constitutive model was compiled into finite-element software as a user material subroutine (VUHARD). The reliability of the established constitutive model was verified by simulating the free hydro-bulging process of welded tubes. The results indicated that the continuous constitutive model can well describe the deformation response during the free hydro-bulging process, and accurately predicted the equivalent strain distribution and thickness thinning rate. This study provides guidance in accurately predicting the plastic deformation behavior of welded tubes and its application in practice in hydroforming industries. [ABSTRACT FROM AUTHOR]

Despite a growing literature supporting the salutary effects of mindfulness meditation on emotion regulation, the underlying mechanisms linking neural and subjective changes occurring during the actual practice of meditation with emotion regulatory effects observed after meditation remains virtually unexplored. The current study sought to address this gap in knowledge by testing the hypothesis that adoption of internally-directed focused attention, indexed by increased alpha and theta spectral power, during brief open monitoring (OM) mindfulness meditation predicts reduced emotional reactivity, as measured by the late positive potential (LPP). Results revealed that the OM meditation did not produce demonstrable differences in alpha and theta power but did increase self-reported sleepiness relative to controls. Follow-up analyses showed that sleepiness uniquely moderated the effect of meditation on the LPP, such that less sleepiness during meditation, but not the control audio, corresponded to smaller LPPs to negative images. Change in theta, but not alpha power, between meditation and rest was positively correlated with the LPP even after controlling for sleepiness. Although the primary hypothesis was unsupported, the findings demonstrate that phenomenological and neural changes occurring during OM meditation may modulate its subsequent "off-the-cushion" effects on emotional reactivity. [ABSTRACT FROM AUTHOR]

A nascent line of research aimed at elucidating the neurocognitive mechanisms of mindfulness has consistently identified a relationship between mindfulness and error monitoring. However, the exact nature of this relationship is unclear, with studies reporting divergent outcomes. The current study sought to clarify the ambiguity by addressing issues related to construct heterogeneity and technical variation in mindfulness training. Specifically, we examined the effects of a brief open monitoring (OM) meditation on neural (error-related negativity (ERN) and error positivity (Pe)) and behavioral indices of error monitoring in one of the largest novice non-meditating samples to date (N = 212). Results revealed that the OM meditation enhanced Pe amplitude relative to active controls but did not modulate the ERN or behavioral performance. Moreover, exploratory analyses yielded no relationships between trait mindfulness and the ERN or Pe across either group. Broadly, our findings suggest that technical variation in scope and object of awareness during mindfulness training may differentially modulate the ERN and Pe. Conceptual and methodological implications pertaining to the operationalization of mindfulness and its training are discussed. [ABSTRACT FROM AUTHOR]

Silage quality remains an important issue in farming, as do limitations in the range of products suitable for animal fodder. We therefore explored the microorganisms that are critical for the fermentation quality of paper mulberry silage. Low (unwilted) and high (wilted) dry matter (DM) paper mulberry were harvested at two cutting times. These were ensiled for 0, 3, 7, 14, and 56 days, respectively. Compared with unwilted silages, wilting significantly decreased (p < 0.05) silage pH value, ammonia‐N concentration, and yeast counts but increased (p < 0.05) lactic acid content. In addition, higher (p < 0.05) crude protein (CP) contents were also observed in wilted silages. Next‐generation sequencing (NGS) analysis revealed that wilting reduced the abundance of Enterobacter, while increasing that of Lactobacillus. Single‐molecule real‐time sequencing (SMRT) revealed that the silage was enriched in the lactic acid bacteria (LAB), Lactobacillus rhamnosus after wilting, which showed a positive correlation with CP and lactic acid content. We conclude that wilting may help preserve paper mulberry silage, facilitating its use as a new fodder resource. Moreover, L. rhamnosus has the potential to be developed as a new inoculant for the modulation in wilted silages, particularly paper mulberry silage. [ABSTRACT FROM AUTHOR]

Simple Summary: Paper mulberry (PM) is an unconventional protein feed material, and silage is its main processing method. The present study aimed to investigate the health benefits and meat quality of supplementing Yangzhou geese with paper mulberry silage. Results indicated that paper mulberry silage supplementation had a promotional effect on the growth of Yangzhou geese, the sensory quality of the breast muscles improved, and the nutritional quality enhanced. Untargeted metabolomics analysis demonstrated that PM treatment enhanced guanidinoacetic acid levels in breast muscles and facilitated the metabolism of amino acids and the role of substances in lipid antioxidant pathways. Consequently, paper mulberry could be considered to be a novel protein feed option capable for geese. There have been few investigations into the health benefits and meat quality of supplementing Yangzhou geese with paper mulberry silage. One hundred and twenty 28-day-old Yangzhou geese were selected for the experiment and randomly divided into two groups: a control group (CON) and a paper mulberry silage group (PM), with six replicates in each group. The experiment lasted for a total of 6 weeks. The experiment found that compared with CON, PM had a promoting effect on the average daily weight gain of Yangzhou geese (p = 0.056). Sensory and nutritional analysis of breast muscles revealed a decrease in a* value (p < 0.05) and an increase in protein content (p < 0.05) following PM treatment. Through untargeted metabolomics analysis of breast muscle samples, it was found that 11 different metabolites, including guanidinoacetic acid and other substances, had a positive effect on amino acid metabolism and lipid antioxidant pathways of PM treatment. Overall, the strategy of feeding Yangzhou geese with paper mulberry silage is feasible, which can improve the sensory quality and nutritional value of goose meat. The experiment provides basic data for the application form of goose breeding, so exploring the impact of substances within paper mulberry on goose meat should be focused on in the future. [ABSTRACT FROM AUTHOR]

The naturally attached phyllosphere microbiota play a crucial role in plant-derived fermentation, but the structure and function of phyllosphere endophytes remain largely unidentified. Here, we reveal the diversity, specificity, and functionality of phyllosphere endophytes in alfalfa (Medicago sativa L.) through combining typical microbial culture, high-throughput sequencing, and genomic comparative analysis. In comparison to phyllosphere bacteria (PB), the fermentation of alfalfa solely with endophytes (EN) enhances the fermentation characteristics, primarily due to the dominance of specific lactic acid bacteria (LAB) such as Lactiplantibacillus, Weissella, and Pediococcus. The inoculant with selected endophytic LAB strains also enhances the fermentation quality compared to epiphytic LAB treatment. Especially, one key endophytic LAB named Pediococcus pentosaceus EN5 shows enrichment of genes related to the mannose phosphotransferase system (Man-PTS) and carbohydrate-metabolizing enzymes and higher utilization of carbohydrates. Representing phyllosphere, endophytic LAB shows great potential of promoting ensiling and provides a novel direction for developing microbial inoculant. The study reveals the diversity, specificity and functionality of phyllosphere endophytes in alfalfa silage fermentation and finds a unique microbe resource in phyllosphere endophytes which tends to enrich genes related to carbohydrate utilization. [ABSTRACT FROM AUTHOR]

Lung cancer is the most common cancer worldwide. Epigenetic modifications like DNA methylation play fundamental roles in the dynamic process of lung cancer. The objective of this study was to use methyl-CpG binding domain protein-enriched genome sequencing (MBD-Seq) to identify novel and high-confidence DNA methylation in lung tumor. We first compared the whole-genome DNA methylation of three lung cancer cell lines, including A549, H1299, and SK-MES-1, against BEAS-2B, a lung/bronchial normal epithelial cell line. We then used pyrosequencing and OneStep qMethyl kit methods to verify the results in the cell line specimens. MBD-Seq identified 279, 8046, and 22 887 differentially methylated regions (DMRs), respectively, with 120 common DMRs among three comparison groups. Three DMRs were consistent with the MBD-Seq results by both pyrosequencing and OneStep qMethyl validations. Furthermore, OneStep qMethyl kit was also performed for functional validation of these three potential DMRs in sputum DNA from clinical participants. We successfully identified one new DMR adjacent to ATG16L2. The novel DMR might have an important function in lung carcinogenesis. Further validation of the finding in clinical specimens of lung cancer patients and functional analysis of this novel DMR in the development of lung cancer through transcriptional silencing of ATG16L2 are warranted. [ABSTRACT FROM AUTHOR]

Background: Noncoding RNAs such as circular RNAs (circRNAs) are abundant in the human body and influence the occurrence and development of various diseases. Non-small cell lung cancer (NSCLC) is one of the most common malignant cancers. Information on the functions and mechanism of circRNAs in lung cancer is limited; thus, the topic needs more exploration. The purpose of this study was to identify aberrantly expressed circRNAs in lung cancer, unravel their roles in NSCLC progression, and provide new targets for lung cancer diagnosis and therapy. Methods: High-throughput sequencing was used to analyze differential circRNA expression in patients with lung cancer. qRT‒PCR was used to determine the level of circHERC1 in lung cancer tissues and plasma samples. Gain- and loss-of-function experiments were implemented to observe the impacts of circHERC1 on the growth, invasion, and metastasis of lung cancer cells in vitro and in vivo. Mechanistically, dual luciferase reporter assays, fluorescence in situ hybridization (FISH), RNA immunoprecipitation (RIP) and RNA pull-down experiments were performed to confirm the underlying mechanisms of circHERC1. Nucleocytoplasmic localization of FOXO1 was determined by nucleocytoplasmic isolation and immunofluorescence. The interaction of circHERC1 with FOXO1 was verified by RNA pull-down, RNA immunoprecipitation (RIP) and western blot assays. The proliferation and migration of circHERC1 in vivo were verified by subcutaneous and tail vein injection in nude mice. Results: CircHERC1 was significantly upregulated in lung cancer tissues and cells, ectopic expression of circHERC1 strikingly facilitated the proliferation, invasion and metastasis, and inhibited the apoptosis of lung cancer cells in vitro and in vivo. However, knockdown of circHERC1 exerted the opposite effects. CircHERC1 was mainly distributed in the cytoplasm. Further mechanistic research indicated that circHERC1 acted as a competing endogenous RNA of miR-142-3p to relieve the repressive effect of miR-142-3p on its target HMGB1, activating the MAPK/ERK and NF-κB pathways and promoting cell migration and invasion. More importantly, we found that circHERC1 could bind FOXO1 and sequester it in the cytoplasm, adjusting the feedback AKT pathway. The accumulation of FOXO1 in the cytosol and nuclear exclusion promoted cell proliferation and inhibited apoptosis. CircHERC1 is a new circRNA that promotes tumor function in NSCLC and may serve as a potential prognostic biomarker and therapeutic target for NSCLC. Conclusions: CircHERC1 is a new circRNA that promotes tumor function in NSCLC and may serve as a potential diagnosis biomarker and therapeutic target for NSCLC. Our findings indicate that circHERC1 facilitates the invasion and metastasis of NSCLC cells by regulating the miR-142-3p/HMGB1 axis and activating the MAPK/ERK and NF-κB pathways. In addition, circHERC1 can promote cell proliferation and inhibit apoptosis by sequestering FOXO1 in the cytoplasm to regulate AKT activity and BIM transcription. [ABSTRACT FROM AUTHOR]

Introduction: Confocal laser endomicroscopy (CLE) has the characteristics of high resolution, real-time imaging, and no radiation, which is helpful for the precise and effective implementation of transbronchial cryobiopsy (TBCB). The study aimed to compare the efficacy and safety of TBCB combined with CLE (CLE group) or fluoroscopy (fluoroscopy group) in the diagnosis of interstitial lung disease (ILD). Methods: From a prospective randomized controlled trial, 80 patients with undiagnosed ILD or ILD requiring biopsy between January 2022 and November 2022 were randomly assigned to CLE group and fluoroscopy group. The rate to reach an etiological diagnosis of ILD, maximum cross-sectional area of specimens, operation time, and complications were compared between the two groups. Results: The rate to reach an etiological diagnosis in the CLE group was significantly higher than that in the fluoroscopy group (95.0% vs. 80.0%, p < 0.05), but there was no difference in the maximum cross-sectional area of the specimens (42.1 ± 10.1 mm2 vs. 41.5 ± 10.3 mm2, p > 0.05). In terms of operation time, the CLE group was significantly shorter than the fluoroscopy group (37.6 ± 10.6 min vs. 54.8 ± 24.9 min, p < 0.05). The bleeding volume in the CLE group was significantly lower than that in the fluoroscopy group (4.9 ± 3.6 mL/case vs. 9.0 ± 9.2 mL/case, p < 0.05). Further analysis showed that the incidence of moderate bleeding was also lower in the CLE group (20.0% vs. 75.0%, p < 0.001). In addition, the incidence of pneumothorax in the CLE group was significantly lower than that in the fluoroscopy group (0 vs. 25.0%, p < 0.001). Conclusions: Compared with simple fluoroscopy, the combination of CLE significantly improves the rate of etiological diagnosis, shortens the operation time, and reduces complications such as bleeding and pneumothorax. [ABSTRACT FROM AUTHOR]

The formation of local features in complex-shaped components is very difficult during rapid hot gas forming. To characterize the local formability of an Al-Mg-Si alloy sheet, free-bulging test and corner-filling test at different temperatures and pressurizing conditions were conducted in this study. The effects of temperature (400 ~ 500 °C) and strain rate (0.1 ~ 10 s-1) on the local formability were analyzed in detail. The local formability was reflected by the ultimate bulging ability and corner filling ability. The reason for local filling behavior was revealed from the theoretical point of view. The sheet had good bulging formability at elevated temperatures and high strain rates. The ultimate bulging ability was almost similar to the decreasing diameter of bugling die. The ultimate strain could reach 0.78 when the temperature was 500 °C, the strain rate was 1.5 s-1, and the diameter of the bugling die was 10 mm. The filling ability increased as the temperature and pressure increased. A corner radius of 2.50 mm was obtained within 1 s when the temperature was 500 °C and the pressurizing rate was 10 MPa/s. In practice, complex-shaped components with local features could be formed within several seconds by hot gas forming. [ABSTRACT FROM AUTHOR]

Highlights • A new definition of the initial inhomogeneity coefficient f 0 in M–K model has been proposed, which can be determined directly using the maximum thickness t max and the minimum thickness t min on tubes extruded with initial eccentricity. • A modified M–K model has been proposed for tubes extruded with initial eccentricity, and the predicted FLC is not as sensitive to f 0 as for sheet metals because the f 0 falls into the region far away from the ideal condition f 0 = 1.0. • Controlled hydro-bulging tests have been used to validate the modified M–K model. It is shown that the modified M–K model can give good prediction of the forming limit for aluminum alloy extruded tube with initial eccentricity. Abstract Thickness deviation in hoop direction is often observed in thin-walled extruded tubes, which is mainly due to the eccentric position of extrusion mandrel. This imperfection in thickness may result in different deformation pattern and consequently different formability. The influence of initial thickness deviation caused by extrusion eccentricity on deformation is investigated by FE analysis first. Radial expansion, hoop stress distribution, and change of cross-section during free hydro-bulging are analyzed. The maximum and minimum wall thicknesses are used to characterize the thickness deviation directly. A new definition of initial inhomogeneity coefficient in M–K model is proposed, and consequently a modified M–K model is proposed specially for tubes extruded with eccentricity. Controlled hydro-bulging test of AA6061-F extrusion is then carried out to verify the modified M–K model. It is shown that asymmetrical deformation tends to occur in free hydro-bulging process of aluminum alloy tubes extruded with initial eccentricity. Higher stress appears in the region with thinner thickness, and expansion occurs first. The original circular cross-section changes its shape to ellipse as hydro-bulging proceeds. The bigger the initial eccentricity is, the bigger the ellipticity of the deformed section. As the initial eccentricity is introduced in defining the initial inhomogeneity coefficient, the modified M–K model can be determined directly, without any requirement of experimental data. Based on the modified M–K model, the theoretical predictions of forming limit curves on the right side of FLD agree well with the experimental results determined by controlled hydro-bulging test. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

The virus that infects bacteria known as phage, plays a crucial role in the biogeochemical cycling of nutrients. However, the community structure and potential functions of phages in silage fermentation remain largely unexplored. In this study, we utilized viral metagenomics (viromics) to investigate the types, lifestyles, functions, and nutrient utilization patterns of phages in silage. Our findings indicated a high prevalence of annotated phages belonging to Caudovirales and Geplafuvirales, as well as unclassified phages in silage. The predominant host types for these phages were Campylobacterales and Enterobacterales. Virulent phages dominated the silage environment due to their broader range of hosts and enhanced survival capabilities. All identified phages present in silage were found to be non-pathogenic. Although temperate and virulent phages carried distinct genes associated with nutrient cycling processes, the shared genes (prsA) involved in carbon metabolism underscore the potential significance of phages in regulating carbon metabolism in silage. Overall, our findings provide a valuable foundation for further exploring the complex interactions between phages and microorganisms in regulating silage fermentation quality. • The viruses present in silage are primally phages and non-pathogenic. • The primary bacterial host of phages belong to the Proteobacteria. • Virulent phages show higher abundance and broader host range than temperate phages. • The phages could express the genes associated with nitrogen and carbon metabolism. [ABSTRACT FROM AUTHOR]

• Hot gas free bulging test was proposed to evaluate the biaxial formability post solution heat treatment in HFQ process. • The temperature and pressurizing rate dependences of limiting bulging and uniform deformation abilities were clarified. • Excellent formability and thickness uniformity can be obtained simultaneously under rapid pressurizing conditions. • The deformation mechanism under biaxial tension state was revealed by microstructure observation. [Display omitted] Hot forming-quenching integrated process was developed to fabricate aluminum alloy complex-shaped components by taking advantage of the enhanced formability at the temperature close to solution temperature. But, it is very difficult to evaluate the formability under biaxial tension state and continuous cooling conditions. A measuring method was proposed to evaluate the biaxial formability by combining solution heat treatment and hot gas free bulging test. The effects of temperature and pressurizing rate on the bulging ability and thickness uniformity of an Al-Mg-Si alloy sheet were clarified. The deformation mechanism was revealed by microstructure observation. It is found that excellent formability can be obtained under the high temperature with less heat loss and rapid pressurizing conditions. The limiting strain under rapid pressurizing condition decreases from 1.13 at 500 ℃ to 0.81 at 400 ℃, being at a high strain level. Thickness uniformity can be obviously improved at a higher deformation temperature accompanied by rapid loading due to the remarkable strain-rate hardening effect. Dynamic recovery is the main restoration mechanism, resulting in numerous substructures and unchanged grain size. The obtained biaxial formability closer to actual forming condition can provide fundamental guidance for forming aluminum alloy complex-shaped component by hot forming-quenching integrated process. [ABSTRACT FROM AUTHOR]

Simple Summary: Forage oat is an important feed resource in the world. Few studies on the application of different bacterial additives in forage oat silage have been found, which limits the utilization and promotion of oat silage in animal husbandry. In this study, we compared the fermentation quality and in vitro gas production of oat silage treated with four additives (Lactiplantibacillusplantarum F1,LP; Lacticaseibacillusrhamnosus XJJ01, LR; Lacticaseibacillusparacasei XJJ02, LC; and Propionibacterium acidipropionici 1.1161, PP). The results show that compared to the CK group (without additives), the LR group had a higher dry matter content, while the LP group showed an improvement in fermentation quality. At the same time, the bacterial community in the LR group was also different from that in other groups. The treatments of PP and LC had no significant effects on fermentation quality, but the in vitro gas production was significantly reduced in the treated oat silage. These results could help us to optimize the utilization of forage oat silage in balanced ruminant diets. Bacterial inoculants are considered as a good choice for successful ensiling, playing a key role in improving the silage quality. However, the potential of different bacteria, especially the propionic acid bacteria, in forage oat ensiling is yet to be explored. Therefore, the purpose of this study was to investigate the regulation effects of different bacterial additives on the fermentation quality of forage oat silage. Four additives (Lactiplantibacillus plantarum F1, LP; Lacticaseibacillus 0rhamnosus XJJ01, LR; Lacticaseibacillus paracasei XJJ02, LC; and Propionibacterium acidipropionici 1.1161, PP; without additives, CK) were inoculated in forage oat silage, and the fermentation quality and organic compounds were determined after 60 days of ensiling. Notably, LR showed higher dry matter preservation compared to other additives and CK. In addition, LP and LR showed strong lactic acid synthesis capacity, resulting in lower pH compared to other additives and CK. The treatments of PP and LC increased the bacterial diversity in silage, while the bacterial community in the LR group was different from that in other groups. In addition, the PP- and LC-treated oat silage showed significantly lower total in vitro gas production and a lower methane content. These results suggest that LP is more favorable for producing high-quality oat silage than LR, LC, or PP. Both the PP- and LC- treated oat silage may reduce rumen greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Hydro-bulging test is an advanced method for characterizing the mechanical properties of tubular materials under bi-axial stress state, by measuring the bulging height, pole thickness and internal pressure. This method has been investigated and applied over the past decades. However, different testing conditions and analytical models have been used in practice, which makes the tested results incomparable. In this paper, hydro-bulging tests with different constraining are first analyzed and compared, and a unified analytical model for stress components calculation is proposed for closed-ends and fixed-ends conditions. Finite element analysis of tube hydro-bulging with closed-ends and fixed-ends shows that both the stress and strain responses of the tubular specimen, i.e., the stress and strain components under different internal pressures, are almost identical to determine the stress–strain relations. Geometrical models for bulging zone are analyzed and compared with special attention on the calculation of the radius of axial curvature, which is one of the key parameters for both stress and strain components determination. A die-related ellipsoid model is presented and is well verified by experimental results on extruded AA6061 tubes. [ABSTRACT FROM AUTHOR]

Hydro-bulging test is a specialized method to obtain the mechanical properties of tubular materials, which is very important for the cases when tubular blank is formed under bi-axial stress states. However, this test is currently applied with different testing conditions and analytical models. In addition, the deformation is often interrupted in order to measure the pole thickness change during testing, which may has considerable effect on final results obtained. Based on the models for stress components and bulging zone profile presented in an accompanying paper, i.e., Part I [19] , analytical model for pole thickness during hydro-bulging test is presented and analyzed. A linear model for pole thickness change is proposed for the first time, and is successfully validated by experiments of AA6061 aluminum tube and SUS409 steel tube. Based on the linear model, the difficulty for pole thickness measuring during hydro-bulging is conquered. Then, a new testing method termed as linear-model based hydro-bulging test , is developed and applied for extruded aluminum alloy tube and roll-welded steel tube. It is demonstrated that the new testing method is more feasible and effective in characterizing the deformation behavior of tubular materials under bi-axial stress states. [ABSTRACT FROM AUTHOR]

Accidental bleeding is an unavoidable problem in daily life. To avoid the risk of excessive blood loss, it is urgent to design a functional material that can quickly stop bleeding. In this study, an efficient wound dressing for hemostasis was investigated. Based on the characteristics that Ca2+ and fish skin collagen (FSC) could activate the coagulation mechanism, hemostatic cotton was prepared by solvent replacement method using CaCl 2 , FSC, soluble starch (SS), and polyvinyl alcohol (PVA) as raw materials. The cytotoxicity test showed the Ca2+PVA/FSC-SS hemostatic cottons had good biocompatibility. The activated partial thromboplastin time (APTT) of Ca2+PVA/FSC-SS(4) was 35.34 s, which was 22.07 s faster than that of PVA/FSC-SS, indicating Ca2+PVA/FSC-SS mediated the endogenous coagulation system. In vitro coagulation test, Ca2+PVA/FSC-SS(4) could stop bleeding rapidly within 39.60 ± 5.16 s, and the ability of wound healing was higher than commercial product (Celox). This study developed a rapid procoagulant and hemostatic material, which had a promising application in a variety of environments. • Ca2+PVA/SS-FSC hemostatic cotton is prepared by solvent displacement and freeze-drying technology. • Ca2+PVA/SS-FSC stops bleeding within 39.60 ± 5.16 s. • Ca2+PVA/SS-FSC can accelerate blood coagulation by aggregating blood cells and fibrinogen. • Ca2+PVA/SS-FSC has good biocompatibility and wound-healing ability. [ABSTRACT FROM AUTHOR]

Abstract: External and internal bending–torsion coupling effects of a rotor system with comprehensive unbalances are studied by analytical analysis and numerical simulations. Based on Lagrangian approach, a full-degree-of-freedom dynamic model of a Jeffcott rotor is developed. The harmonic balance method and the Floquet theory are combined to analyze the stability of the system equations. Numerical simulations are conducted to observe the bending–torsion coupling effects. In the formulation of rotordynamic model, two bending–torsion coupling patterns, external coupling and internal coupling, are suggested. By analytical analysis, it is concluded that the periodic solution of the system is asymptotically stable. From numerical simulations, three bending–torsion coupling effects are observed in three cases. Under static unbalance, synchronous torsional response is observed, which is the result of external coupling under unbalanced force. Under dynamic unbalance, two-time synchronous frequency torsional response is observed, which is the result of internal coupling under unbalanced moment. Under comprehensive unbalance, synchronous and two-time synchronous frequency torsional components are observed, which are the results of both external and internal couplings under unbalanced force and moment. These observations agree with the analytical analysis. It is believed that these observed phenomena should make sense in the dynamical design and fault diagnostics of a rotor system. [Copyright &y& Elsevier]

• A novel controlled biaxial tensile testing system was developed using digital image correlation (DIC) as a measurement tool. • The constitutive model of tubular materials considering the evolution of anisotropic characteristics was calibrated accurately. • The accuracy of the calibrated constitutive model was verified in engineering practices by compiling the model into VUMAT for simulating typical free tube hydro-bulging. • The developed DIC-based controlled biaxial tensile test is an effective method to determine an appropriate anisotropic constitutive model for tubular materials. The reliability of numerical simulation results vitally depends on the accurate determination of the constitutive model, which requires accurate and sufficient experimental data. To address the current limitations of the range and accuracy of the experimental data of tubular materials, a novel controlled biaxial tensile testing device was developed using digital image correlation (DIC) system as the deformation measuring tool. Using such a device, arbitrary biaxial tensile stress path can be accurately applied to tubular specimens, and the strain can be accurately and continuously measured over the whole deformation process. Firstly, the accurate experimental data of AA6061-O tubes were obtained through the controlled biaxial tensile tests. Then, using the experimental data, the constitutive model considering the evolution of anisotropic characteristics was calibrated based on the Yld2000-2d yield criterion. Finally, the accuracy of the calibrated constitutive model was verified in engineering practices by compiling the constitutive model into finite element software as a user material subroutine (VUMAT) for simulating tube hydro-bulging. Excellent agreements were achieved between experimentally-determined and predicted bulge height, bulge profile, and pole thickness of bulged tubes over the whole hydro-bulging process. It is demonstrated that the DIC-based controlled biaxial tensile test is effective to accurately calibrate the constitutive model of tubular materials, which can be used for both the research of plastic deformation behavior and practical application of hydroforming industry. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• The loading paths in tube hydro-bulging with fixed-ends and free-ends are nonlinear. • The loading path in bulging with fixed-ends is related to the length-diameter ratio. • A higher forming limit is expected when using a smaller length-diameter ratio. • The new FLD combining the geometric parameter of tube is convenient and effective. The loading paths of tubular parts containing the characteristic of variable diameter during hydroforming are nonlinear and similar to the loading paths during tube hydro-bulging tests. Therefore, the forming limit determined by hydro-bulging tests is very suitable for guiding the forming of this kind of parts. However, traditional forming limit diagram (FLD) cannot present the nonlinear loading paths. In this paper, a theoretical analysis model for tube hydro-bulging tests is developed first. And then the stress paths and strain paths during bulging with fixed-ends and free-ends are analyzed through the theoretical model and finite element simulations. The results show that as the length-diameter ratio of the bulging zone ranges from 1.0 to 3.0, stress paths and strain paths are obviously nonlinear. For hydro-bulging with fixed-ends, the axial-hoop stress ratio changes gradually from 0.5 towards 1.0, and the strain state changes from plane strain state towards equal-biaxial tension state. For hydro-bulging with free-ends, the stress ratio changes gradually from 0 towards 0.5, and the strain state changes from simple tension state towards plane strain state. In order to give a better characterization of the forming limit of tubes under nonlinear loading paths, a novel FLD combining the geometric parameter of the tubular part is proposed. Two FLDs of an AA6061 aluminum alloy seamless tube under different end conditions are determined by experiments. The results show that both in hydro-bulging with fixed-ends and with free-ends, a higher forming limit is expected when using a smaller length-diameter ratio. As the new FLD can give direct presentation of limit strains together with the end condition and the length-diameter ratio in tube hydroforming, it can be used directly for the analysis and optimization of actual tube hydroforming processes, instead of the simple evaluation of the formability of raw materials. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• A new concept of stepped-die with changing cross section shape is proposed. • Continuous nonlinear loading paths can be realized via bulging with stepped-dies. • Both stress and strain data of the whole process can be obtained during bulging. • The stress ratio changes from 0.5 up to 2.0 at most in one bulging experiment. In this paper, a novel test method named bulging with stepped-dies is proposed to overcome the difficulty of traditional test methods in realizing continuous nonlinear loading paths from initial yield up to fracture on a sheet metal. To achieve this aim, the section shape of a stepped-die cavity is varied with increasing depth. During bulging with a stepped-die, the stress state at the pole of bulging area of the sheet changes continuously with the increase in bulging height, which results in a specific nonlinear loading path. A theoretical model is established to calculate the stress components at the pole based on the assumption that the bulged surface near the pole is approximated by a rotational ellipsoid. Bulging experiments with three different stepped-dies are performed by using ST16 steel sheet. Stress and strain paths up to fracture and equivalent stress-strain curves at the pole are analyzed and compared with the results of bulging with elliptical dies. It is shown that continuous nonlinear loading paths can be effectively realized through bulging with stepped-dies and the stress ratio at the pole changes from 0.5 up to 2.0 at most in one bulging experiment. The feasibility of the novel test method is validated successfully. And the experimental data obtained are useful to determine constitutive and forming limit models suitable for complex loading conditions. Image, graphical abstract [ABSTRACT FROM AUTHOR]

We have demonstrated that assessments of microRNA (miRNA) expressions in circulating peripheral blood mononucleated cell (PBMC) and sputum specimens, respectively, may help diagnose lung cancer. To assess the individual and combined analysis of the miRNAs across the different body fluids for lung cancer early detection, we analyse a panel of 3 sputum miRNAs (miRs-21, 31, and 210) and a panel of 2 PBMC miRNAs (miRs-19b-3p and 29b-3p) in a discovery cohort of 68 patients with lung cancer and 66 cancer-free smokers. We find that integrating 2 sputum miRNAs (miRs-31 and 210) and 1 PBMC miRNA (miR-19b-3p) has higher sensitivity (86.8%) and specificity (92.4%) compared with the individual panels. The synergistic value of the integrated panel of 3 biomarkers is confirmed in a validation cohort, independent of stage and histological type of lung cancer, and patients' age, sex, and ethnicity. Integrating circulating immunological and sputum biomarkers could improve the early detection of lung cancer. [ABSTRACT FROM AUTHOR]

In this article, we organize multimethod, multitimescale data around the interpersonal situation, a conceptual framework that can be used to integrate personality, psychopathology, and psychotherapy constructs in order to guide the assessment of clinical dynamics. We first describe the key variables of the interpersonal situation model and articulate methods for assessing those variables as they manifest (a) across different levels of personality, (b) across situations, and (c) within situations. We next use a case to demonstrate how to assess aspects of the interpersonal situation in a manner that enhances case conceptualization and facilitates the evaluation of clinical hypotheses. We also use this case to highlight challenges and decisions involved in implementing dynamic assessment in psychotherapy. We conclude by outlining areas in need of further exploration toward a more sophisticated approach to clinical practice that involves the routine assessment of dynamic processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • First to show the diverse effect of herbal residues on fermentation quality. • Herbal residues addition significantly decreased NH 3 -N content. • Adding herbal residues changed fermentation quality by altering microbiota. • Carbohydrate metabolism was enhanced with herbal residues addition. • Herbal residues provided new insights for improving anaerobic fermentation. In order to increase the utilization of herbal residues, realize efficient utilization of resources, the bacterial community and anaerobic fermentation characteristics of alfalfa ensiling treated with 36 kinds of herbal residues were studied. All the herbal residues improved the anaerobic fermentation quality in different degrees, indicated by lower pH, NH 3 -N and butyric acid concentrations. However, the contents of lactic and acetic acids varied widely in silage with different herbal residues. Pearson's correlation analysis showed that the improved fermentation quality was closely associated with the variation of lactic acid bacteria community. Consequently, the herbal residues could improve anaerobic fermentation quality by stimulating desirable Lactobacillus species and inhibiting undesirable microbes. This study provides new insights for efficient utilization of herbal residues. [ABSTRACT FROM AUTHOR]

• An enhanced constitutive model was proposed based on the Yld2000–2d model. • The enhanced model improves the model applicability and accuracy for introduction of an additional term. • The yield and plastic flow behaviors of anisotropic tubes in both biaxial tension and pure shear stress states can be considered simultaneously. • The yield loci and plastic flow directions of the tubes in both biaxial tension and pure shear stress states can be accurately predicted by the enhanced model. • The enhanced model is validated to be efficient and accurate in simulation of tube hydroforming. In forming of complex thin-walled tubular parts, such as tube hydroforming with axial feeding, both biaxial tension and one axial tension & one axial compression (around the pure shear stress state) deformations are involved. The deformations under both biaxial tension and pure shear stress conditions cannot be accurately modeled and described with the symmetrical constitutive models based on the tensile properties. It is due to the fact that the anisotropic yielding and plastic flow behaviors of tubes are not well articulated over the entire range of stress states. To address this issue, an enhanced constitutive model was proposed based on the Yld2000–2d model (Barlat et al., 2003). The enhanced model improves the applicability of the Yld2000–2d by introducing an additional term, which can flexibly describe the change of the curvature of yield locus around the pure shear stress state. The yielding and plastic flow characteristics of the tubes under both biaxial tension and pure shear stress conditions can be well considered by the enhanced model and the model convexity can be strictly guaranteed. Moreover, the predictability of the proposed model for the deformation behaviors under these states was analyzed and compared with the quoted anisotropic constitutive models. The accuracy and efficiency were also verified and corroborated with the forming of AA6061-O tubes. It showed that the enhanced constitutive model can accurately predict the experimental yield loci and the plastic flow directions of the AA6061-O tube under both biaxial tension and pure shear stress deformations. The in-depth comparisons with the three benchmarked models and experiments were also conducted in terms of the predicted profile and wall thickness distribution of tube hydroforming, in such a way to further validate the enhanced model in terms of the efficiently and accurately modeling of the forming of complex tubes. [ABSTRACT FROM AUTHOR]

Silver, with excellent physicochemical properties, has been widely used in modern industry. Silver recovery from end-of-life product is economically significant for sustainability. However, silver leaching solution (SLS) containing diverse heavy metal ions as well as dissolved silica is a challenging waste stream for treatment and silver recovery. In this work we explored treatment of a real SLS via direct contact membrane distillation (DCMD). Results showed that silica scaling in DCMD process was closely related to the coexisting aluminum ions (Al3+) in SLS. The amount of Al(OH) 3 formed was dependent on the initial pH of SLS and was effective to reduce concentration of the total dissolved silica in SLS, which was the key factor that influenced particle size distribution of SLS and degree of silica scaling. The highest silica removal rate of 83.7% was achieved at pH of 11. Moreover, it was found that the Al(OH) 3 with positive charge accelerated mono-silicic acids aggregation, leading to prompt silica polymerization. This hypothesis was underpinned by evidence that amorphous yet compact aggregates formed on membrane surface and trimer silicates formed in the concentrated SLS with initial pH of 11. As a result, the most severe silica scaling occurred during DCMD treatment of SLS, resulting in the lowest initial permeate flux and water recovery. Our results shed light on prevention and management of silica scaling in treatment of waste stream. Image 1 • The coexisting metal ions Al3+ participated in silica scaling was proved. • The amount of Al(OH) 3 formed was the key factor that influenced the degree of silica scaling. • Al(OH) 3 as absorbent with positive charged influenced the particle size distribution of SLS. • Silicic acids aggregated and polymerized fast in SLS in the presence of Al(OH) 3. • The most severe silica scaling on DCMD performance occurred at initial pH of 11. [ABSTRACT FROM AUTHOR]

Precious metals, such as platinum group metals (PGMs) with distinct catalytic activity, are widely used as active components in various industrial catalysts. It is, therefore, highly desirable to recover these valuable components from the end-of-life products. We explored treatment of refining wastewater from precious metals recovery using direct contact membrane distillation (DCMD). The role of various initial pH of refining wastewater on DCMD performance was assessed. Results suggested that hydrochloride acid (HCl) and high-quality water can be reclaimed from the real refining wastewater by adjusting initial pH. Furthermore, DCMD water flux decline was mainly caused by silica and chromium (III) scaling, which was dependent on initial pH of refining wastewater. Silica scaling was responsible for the decrease of DCMD performance when the initial pH of refining wastewater increased from original 0.03 to 5 and 7. Silica oligomers in the concentrated feed with various initial pH were identified using mass spectra. Dichlorotetraaquochromiun was identified by X-ray photoelectron spectroscopy and ultraviolet and visible absorbance spectra as the main species contributing to the green colour and scaling on the PTFE membrane surface. Our results suggest that DCMD can be used as a promising and feasible solution for resource recovery from acidic refining waste stream. Image 1 • DCMD process was first applied to the treatment of real refining waste stream. • High-quality hydrochloride acid (HCl) was recovered. • System performance was negatively influenced by silica and chromium (III) scaling. • Chromium (III) scaling was dependent on initial pH of feed. • Chemistry of silica and chromium (III) in membrane scaling was elucidated. [ABSTRACT FROM AUTHOR]

Resveratrol is one of the most studied plant secondary metabolites owing to its numerous health benefits. It is accumulated in some plants following biotic and abiotic stress pressures, including UV-C irradiation. Polygonum cuspidatum represents the major natural source of concentrated resveratrol but the underlying mechanisms as well as the effects of UV-C irradiation on resveratrol content have not yet been documented. Herein, we found that UV-C irradiation significantly increased by 2.6-fold and 1.6-fold the resveratrol content in irradiated leaf samples followed by a dark incubation for 6 h and 12 h, respectively, compared to the untreated samples. De novo transcriptome sequencing and assembly resulted into 165,013 unigenes with 98 unigenes mapped to the resveratrol biosynthetic pathway. Differential expression analysis showed that P.cuspidatum strongly induced the genes directly involved in the resveratrol synthesis, including phenylalanine ammonia-lyase, cinnamic acid 4-hydroxylase, 4-coumarate-CoA ligase and stilbene synthase (STS) genes, while strongly decreased the chalcone synthase (CHS) genes after exposure to UV-C. Since CHS and STS share the same substrate, P. cuspidatum tends to preferentially divert the substrate to the resveratrol synthesis pathway under UV-C treatment. We identified several members of the MYB, bHLH and ERF families as potential regulators of the resveratrol biosynthesis genes. [ABSTRACT FROM AUTHOR]