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The machining of monolithic components is prone to deformation, which causes a large amount of production resources to be wasted. Therefore, studying the process of initial configuration optimization method to reduce machining deformation is of great significance for the precision machining of monolithic components. In this paper, the concept and mathematical expression of the initial process configuration are proposed for aluminum alloy U-shaped cross-section stringer structural components. The initial configuration optimization problem is formulated with the initial process configuration as the variable and the objective of minimizing machining deformation. An iterative method is used to optimize the initial process configuration. The machining deformation after the optimized configuration was analyzed by finite element simulation and theoretical calculation, and the deformation data error of the two was less than 20%, which verified the correctness of the method proposed in this paper. Machining tests were carried out, and the results show that the proposed initial configuration optimization method can control the deformation of the U-shaped long truss parts within ± 0.06 mm/m, which is 80–90% less than that before optimization. This initial configuration optimization method has a positive effect on controlling machining deformation. [ABSTRACT FROM AUTHOR]

The deep-sea open ocean habitat (below 200 m depth) is comprised of little-to-no light, near freezing temperatures, and vastly connected stratified waters. Bioluminescence is often linked to the success and diversification of fishes in these dark deep-sea habitats, which are host to many species-rich and morphologically diverse clades. Fish bioluminescence takes many forms and is used in a variety of behaviors including counterillumination, prey detection and luring, communication, and predator avoidance. This study focuses on lanternfishes (Myctophidae), a diverse group (252 spp. in 34 genera) of deep-sea fishes in which bioluminescence has played a critical role in their diversification. Using histological techniques, we provide new morphological analyses of the complex structure of the primary photophores of representative species from 17 genera in which photophore morphology has not previously been described. We combine this information with data from prior studies to compare primary photophore characteristics for species representing all 34 lanternfish genera. Although we find that lanternfish primary photophores are similar in many of their structural components, including the possession of a modified scale cup, photocytes, pigment, and reflector layers, we observe significant variation among species in other aspects of photophore morphology. Observed morphological differences include variation in pigmentation and in the calcification and thickness of the modified scale cup. We also find reflectors that are very thin or absent in gymnoscopeline and lampanyctine species, relative to the robust reflectors present in myctophine species. We find evidence of secondary reflectors and secondary pigment layers in six lanternfish species and observe major differences in scale-lens thickness and mineralization across the assemblage. Lastly, Scopelopsis multipunctatus is the only species analyzed lacking a photophore cup. Obtaining finer detail of light organ morphology across this species-rich lineage provides much-needed insight into the factors that have contributed to the remarkable diversity of lanternfishes in the deep open ocean. [ABSTRACT FROM AUTHOR]

HIV-1 capsid protein (CA) is essential for viral replication and interacts with numerous host factors to facilitate successful infection. Thus, CA is an integral target for the study of virus-host dynamics and therapeutic development. The multifaceted functions of CA stem from the ability of CA to assemble into distinct structural components that come together to form the mature capsid core. Each structural component, including monomers, pentamers, and hexamers, presents a variety of solvent-accessible surfaces. However, the structure-function relationships of these components that facilitate replication and virus-host interactions have yet to be fully elucidated. A major challenge is the genetic fragility of CA, which precludes the use of many common methods. To overcome these constraints, we identified CA-targeting aptamers with binding specificity for either the mature CA hexamer lattice alone or both the CA hexamer lattice and soluble CA hexamer. To enable utilization of these aptamers as molecular tools for the study of CA structure-function relationships in cells, understanding the higher-order structures of these aptamers is required. While our initial work on a subset of aptamers included predictive and qualitative biochemical characterizations that provided insight into aptamer secondary structures, these approaches were insufficient for determining more complex non-canonical architectures. Here, we further clarify aptamer structural motifs using focused, quantitative biophysical approaches, primarily through the use of multi-effective spectroscopic methods and thermodynamic analyses. Aptamer L15.20.1 displayed particularly strong, unambiguous indications of stable RNA G-quadruplex (rG4) formation under physiological conditions in a region of the aptamer also previously shown to be necessary for CA-aptamer interactions. Non-canonical structures, such as the rG4, have distinct chemical signatures and interfaces that may support downstream applications without the need for complex modifications or labels that may negatively affect aptamer folding. Thus, aptamer representative L15.20.1, containing a putative rG4 in a region likely required for aptamer binding to CA with probable function under cellular conditions, may be a particularly useful tool for the study of HIV-1 CA. [ABSTRACT FROM AUTHOR]

While our understanding of pain is rapidly growing, some areas of pain research are lagging behind. This article discusses two current and inter-related gaps in knowledge that are in need of addressing: first, the connections between “brain” and “body” components of pain; and second, the process of endogenous pain resolution. Historical reasons for these research gaps are discussed and solutions are outlined based on an integrative, whole person research approach. These include comprehensive mapping of the mechanosensory and nociceptive innervation of deep tissues; developing objective, non-invasive measurements to quantify the metabolic, structural and mechanical components of the peripheral tissue environment; integrating our understanding of pain pathophysiology, across whole organs and whole body, as well as across bio-psycho-social domains; and understanding the interplay of nervous system and peripheral tissue mechanisms that promote the endogenous resolution of pain and prevent its acute-to-chronic transition. Current NIH-led efforts in these areas are outlined, including several studies within the NIH HEAL (or Help End Addition Long Term) initiative and the National Center for Complementary and Integrative Health’s strategic priorities in whole person research. [ABSTRACT FROM AUTHOR]

A shake table test using a full-scale 2-story steel moment frame was conducted to investigate the peak floor acceleration (PFA) and the peak component acceleration (PCA), which directly affect the seismic demand on nonstructural elements. The main focus of this study was to evaluate the effects of structural and component nonlinearity on the nonstructural seismic demand. The PFA reduction suggested by ASCE 7-22 to account for structural nonlinearity was shown to be larger than the experimental results for low-to-moderate ductility levels. The analysis on the resonant PCA showed the importance of structural nonlinearity on the elastic CAR (=PCA/PFA). The high resonant PCA around the fundamental period of the elastic test frame (7 times PFA) was effectively decreased as the test frame experienced a moderate level of ductility; PCA was lowered by 36% and 25% on the 2nd and roof floors, respectively. The effect of component yielding on the PCA was evaluated based on the test results of steel racks mounted on flexible and rigid access floors. The PCA reduction depending on the component ductility level was less than the relevant provisions of ASCE 7-22, and the reason was discussed from the perspective of the pinched hysteretic behavior of the tested specimens. [ABSTRACT FROM AUTHOR]

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Covalent Organic Frameworks (COFs) exhibit a range of exceptional attributes, including notable porosity, outstanding stability, and a precisely tuned π‐conjugated network, rendering them highly promising candidates for fluorescence sensors applications. In this study, the synthesis of two emissive hydrazone‐linked COFs designed for hydrazine detection is presented. The partially conjugated structure of the hydrazone linkage effectively weakens the fluorescence quenching processes induced by aggregation. Additionally, the incorporation of flexible structural components further reduces conjugation, thereby enhancing luminescent efficiency. Remarkably, these COFs possess a significant abundance of heteroatoms, enabling distinctive interactions with hydrazine molecules, which in turn results in exceptional selectivity and sensitivity for hydrazine detection. The detection limit of these COFs reaches the nanomolar range, surpassing all previously reported COFs, thereby underscoring their superior performance in chemical sensing applications. [ABSTRACT FROM AUTHOR]

Phosphoinositides, such as PI(4,5)P2, are known to function as structural components of membranes, signalling molecules, markers of membrane identity, mediators of protein recruitment and regulators of neurotransmission and synaptic development. Phosphatidylinositol 4‐kinases (PI4Ks) synthesize PI4P, which are precursors for PI(4,5)P2, but may also have independent functions. The roles of PI4Ks in neurotransmission and synaptic development have not been studied in detail. Previous studies on PI4KII and PI4KIIIβ at the Drosophila larval neuromuscular junction have suggested that PI4KII and PI4KIIIβ enzymes may serve redundant roles, where single PI4K mutants yielded mild or no synaptic phenotypes. However, the precise synaptic functions (neurotransmission and synaptic growth) of these PI4Ks have not been thoroughly studied. Here, we used PI4KII and PI4KIIIβ null mutants and presynaptic‐specific knockdowns of these PI4Ks to investigate their roles in neurotransmission and synaptic growth. We found that PI4KII and PI4KIIIβ appear to have non‐overlapping functions. Specifically, glial PI4KII functions to restrain synaptic growth, whereas presynaptic PI4KIIIβ promotes synaptic growth. Furthermore, loss of PI4KIIIβ or presynaptic PI4KII impairs neurotransmission. The data presented in this study uncover new roles for PI4K enzymes in neurotransmission and synaptic growth. [ABSTRACT FROM AUTHOR]

Incorporating diverse components into metal–organic frameworks (MOFs) can expand their scope of properties and applications. Stratified MOFs (sMOFs) consist of compositionally unique concentric domains (strata), offering unprecedented complexity through partitioning of structural and functional components. However, the labile nature of metal‐ligand coordination handicaps achieving compositionally distinct domains due to ligand exchange reactions occurring concurrently with secondary strata growth. To achieve complex sMOF compositions, characterizing and controlling the competing processes of new strata growth and ligand exchange are vital. This work systematically examines controlling ligand exchange in UiO‐67 sMOFs by tuning ligand sterics. We present quantitative methods for assessing and visualizing the outcomes of strata growth and ligand exchange that rely on high‐angle annular dark‐field images and elemental mapping via scanning transmission electron microscopy‐energy dispersive X‐ray spectroscopy. In addition, we leverage ligand sterics to create 'blocking layers' that minimize ligand exchange between strata which are particularly susceptible to ligand exchange and inter‐strata ligand mixing. Finally, we evaluate strata compositional integrity in various solvents and find that sMOFs can maintain their compositions for >12 months in some cases. Collectively, these studies and methods enhance understanding and control over ligand placement in multi‐domain MOFs, factors that underscore careful tunning of properties and function. [ABSTRACT FROM AUTHOR]

Currently, horizontal well fracturing is indispensable for shale gas development. Due to the variable reservoir formation morphology, the drilling trajectory often deviates from the high-quality reservoir, which increases the risk of fracturing. Accurately recognizing low-amplitude structures plays a crucial role in guiding horizontal wells. However, existing methods have low recognition accuracy, and are difficult to meet actual production demand. In order to improve the drilling encounter rate of highquality reservoirs, we propose a method for fine recognition of low-amplitude structures based on the non-subsampled contourlet transform (NSCT). Firstly, the seismic structural data are analyzed at multiple scales and directions using the NSCT and decomposed into low-frequency and high-frequency structural components. Then, the signal of each component is reconstructed to eliminate the low-frequency background of the structure, highlight the structure and texture information, and recognize the lowamplitude structure from it. Finally, we combined the drilled horizontal wells to verify the lowamplitude structural recognition results. Taking a study area in the west Sichuan Basin block as an example, we demonstrate the fine identification of low-amplitude structures based on NSCT. By combining the variation characteristics of logging curves, such as organic carbon content (TOC), natural gamma value (GR), etc., the real structure type is verified and determined, and the false structures in the recognition results are checked. The proposed method can provide reliable information on lowamplitude structures for optimizing the trajectory of horizontal wells. Compared with identification methods based on traditional wavelet transform and curvelet transform, NSCT enhances the local features of low-amplitude structures and achieves finer mapping of low-amplitude structures, showing promise for application. [ABSTRACT FROM AUTHOR]

The Pinghu slope belt in the Xihu sag of the East China Sea Shelf Basin (ECSSB) is a crucial hydrocarbon production area in eastern China. However, due to the complex geological conditions, publications have lacked comprehensive research on the spatial-temporal coupling relationships of primary factors that impact hydrocarbon accumulation in the Pinghu slope belt. Furthermore, the hydrocarbon distribution patterns and the controlling factors across different study areas within the same slope belt are not yet fully understood. This study extensively utilized three-dimensional seismic data, well logging data, geochemical analysis, fluorescence analysis, and oil testing and production data to address these issues. Following a "stratification and differentiation" approach, the study identified seven distinct hydrocarbon migration and accumulation units (HMAU) in the Pinghu slope area based on the structural morphology characteristics, hydrocarbon source-reservoir-cap rock patterns, hydrocarbon migration pathways, and hydrocarbon supply range. Detailed analysis was conducted to examine the hydrocarbon distribution patterns and controlling factors within each migration and accumulation unit across different structural units, including high, medium, and low structural components. All data sources support a "southern-northern sub-area division, eastern-western sub-belt division, and variations in hydrocarbon accumulation" pattern in the Pinghu slope belt. The degree of hydrocarbon accumulation is controlled by the factors of structural morphology, hydrocarbon generation potential of source rocks, the spatial position of source slopes, fault sealing capacity, and sand body distribution. Furthermore, different coupling patterns of faults and sand bodies play a pivotal role in governing hydrocarbon enrichment systems across various migration and accumulation units. These observations indicate that three hydrocarbon accumulation patterns have been established within the slope belt, including near-source to far-source gentle slope with multiple hydrocarbon kitchens in the XP1-XP4 zones, near-source to middle-source gentle slope with dual-hydrocarbon kitchens in the XP5 zone, and near-source steep slope with a single hydrocarbon kitchen in the XP6-XP7 zones. These findings contribute to enhancing the theoretical system of hydrocarbon accumulation in the slope belt. [ABSTRACT FROM AUTHOR]

Background: Although most engineering graduate students are funded and usually complete their degrees faster than other disciplines, attrition remains a problem in engineering. Existing research has explored the psychological and sociological factors contributing to attrition but not the structural factors impacting attrition. Purpose/Hypothesis: Using systems theory, this study seeks to understand nuance in how underlying structural causes affect engineering graduate students' attrition experiences in ways that may differ from their official reasons for departure. Design/Methods: Data were collected through semi‐structured interviews with seven departing or already departed engineering doctoral students from R1 graduate programs across the United States. Using thematic analysis, root cause analyses were conducted to understand participants' attrition experiences to explore how structures influence causes of departure. Results: The ways participants discuss root causes of their departure indicate differences in formal reasons for departure and underlying causes of departure. We highlight the role of informal and formal policy as root causes of a different attrition rationale often passed off as interpersonal issues. When interpreted as evidence of structural issues, the causes of departure show ways in which action–inaction, policy–"null" policy serve as structural features governing student attrition decision processes. We also highlight a form of benign neglect toward struggling graduate students. Conclusion: This study reveals important nuances underlying face‐value reasons of attrition indicating foundational structural issues contributing to engineering graduate student attrition. Coaching faculty in team management and encouraging close revision of departmental policies could help mitigate students' negative graduate experiences and decrease unnecessary attrition. [ABSTRACT FROM AUTHOR]

The structural-contextual dual frameworks theory comprises two heuristic frameworks that provide alternative means for the interpretation of metaphor in pictorial artworks (Crawford & Juricevic, 2016). The first of these frameworks is the contextual framework, which contends that the interpretation of pictorial metaphors is contextually rooted, and the second is the structural framework which interprets metaphor based on structural components of an artwork. We used these frameworks to analyze the literal and metaphorical use of the pictorial device of exaggerated size in 59 well-known works of art sampled from across history. Exaggerated size was chosen for analysis because it is often used literally (e.g., to depict an actual giant) or metaphorically (e.g., to depict an existential concern). The artworks were sorted into four separate categories (Literal-Literal, Metaphorical-Literal, Literal-Metaphorical, and Metaphorical-Metaphorical) based on their interpretation by the structural and contextual frameworks (respectively). A cumulative Poisson distribution with α <.05 revealed that artists typically produced artworks in all categories except for the incongruent combination of literal contextual information and metaphoric structural information. This suggests that when contextual and structural information conflicts in art, viewers rely on contextual information; when metaphoric and literal information conflicts, viewers favor metaphoric interpretations. This present study supports the idea that the structural-contextual dual frameworks theory may be used to investigate the use of metaphors across art styles and media. These results also provide a guide for combining literal and metaphorical information, whether the goal is ease of communication or to intentionally challenge the viewer. [ABSTRACT FROM AUTHOR]

The stiffness of leaf springs was calculated using the master leaf method and the finite element method. A finite element model of the leaf spring system, incorporating structural components such as the spring seat, was developed. This model takes into account nonlinear factors present in the actual working conditions of the leaf springs, such as large deformations, frictional contact, and hinge rotation. The study analyzed how various factors affect the stiffness of the leaf springs. It was found that the stiffness of the leaf spring system increases with the rise in the friction coefficient between the leaves, and initially increases and then decreases as the preload force is augmented. [ABSTRACT FROM AUTHOR]

Acoustic emission (AE) testing is used for the continuous evaluation of structural integrity and the monitoring of damage evolution in structural components and materials. During operation, the environmental and loading conditions of metal structures can result in corrosion and surface wear damage. The early detection of surface degradation flaws is crucial, as they can serve as local stress concentration points, leading to crack initiation and failure. In this work, the effectiveness of AE in monitoring corrosion and surface wear flaw formation was experimentally evaluated. AE sensors were installed on steel test plates during the artificial induction of corrosion and surface wear in order to detect and record the generated AE signals. Corrosion-related AE signals typically exhibit low amplitude, count, and energy values. The direct detection of active corrosion can be challenging in noisy environments, but it can be carried out under certain conditions using dedicated AE sensor groups. Surface-wear-related AE signals exhibit high amplitude, energy, and count values, with long duration values that are associated with wear and grinding conditions. It was found that AE sensors can be utilised to detect corrosion and surface degradation events. The effectiveness of the AE method in detecting surface degradation in noisy environments can be improved by implementing a filtering methodology. This will limit the recording of noise-related signals that can mask out actual surface degradation AE events. [ABSTRACT FROM AUTHOR]

A novel method for assessing the seismic resilience of railway stations is introduced. With this method, a railway station is divided into five constituent systems. The structural components, nonstructural components, and especially professional equipment that affect the functions in each system are identified and analyzed. Significantly, a new calculation method for seismic resilience indices, encompassing repair cost, repair time, casualties, and resilience grade, is proposed. Additionally, the complete seismic resilience assessment process is outlined. Furthermore, a case study was conducted on a typical railway station in China to demonstrate the application of this new seismic resilience assessment method. [ABSTRACT FROM AUTHOR]

Flexible, adaptive behaviour depends on the application of prior learning to novel contexts (transfer). Transfer can take many forms, but the focus of the present study was on "task schemas"—learning strategies that guide the earliest stages of engaging in a novel task. The central aim was to examine the architecture of task schemas and determine whether strategic task components can expedite learning novel tasks that share some structural components with the training tasks. Groups of participants across two experiments were exposed to different training regimes centred around multiple unique tasks that shared some/all/none of the structural task components (the kinds of stimuli, classifications, and/or responses) but none of the surface features (the specific stimuli, classifications, and/or responses) with the test task (a dot-pattern classification task). Initial test performance was improved (to a degree) in all groups relative to a control group whose training did not include any of the structural components relevant to the test task. The strongest evidence of transfer was found in the motoric, perceptual + categorization, and full schema training groups. This observation indicates that training with some (or all) strategic task components expedited learning of a novel task that shared those components. That is, task schemas were found to be componential and were able to expedite learning a novel task where similar (learning) strategies could be applied to specific elements of the test task. [ABSTRACT FROM AUTHOR]

C1-FDX (Complex I-ferredoxin) has been defined as a component of CI in a ferredoxin bridge in Arabidopsis mitochondria. However, its full function remains to be addressed. We created two c1-fdx mutants in Arabidopsis using the CRISPR-Cas9 methodology. The mutants show delayed seed germination. Over-expression of C1-FDX rescues the phenotype. Molecular analyses showed that loss of the C1-FDX function decreases the abundance and activity of both CI and subcomplexes of CV. In contrast, the over-expression of C1-FDX-GFP enhances the CI* (a sub-complex of CI) and CV assembly. Immunodetection reveals that the stoichiometric ratio of the α:β subunits in the F1 module of CV is altered in the c1-fdx mutant. In the complemented mutants, C1-FDX-GFP was found to be associated with the F' and α/β sub-complexes of CV. Protein interaction assays showed that C1-FDX could interact with the β, γ, δ, and ε subunits of the F1 module, indicating that C1-FDX, a structural component of CI, also functions as an assembly factor in the assembly of F' and α/β sub-complexes of CV. These results reveal a new role of C1-FDX in the CI and CV assembly and seed germination in Arabidopsis. Author summary: The mitochondrial oxidative phosphorylation (OXPHOS) system is composed of five large multiprotein complexes, complex I to V (CI to CV). However, their assembly is not fully understood in plants. C1-FDX, a ferredoxin protein, was found to form a ferredoxin bridge in CI. Here, we show that C1-FDX is also involved in the assembly of CI* and CV. CI* is an important intermedate of CI. Mutation of C1-FDX affects the assembly of these two complexes and delays the germination of Arabidopsis. C1-FDX interacts with several CV subunits, including the β, γ, δ, and ε subunits of the F1 sub-complex, and physically associates with the CV assembly intermediates, sub-complexes F' and α/β, but not with the mature CV, indicating that C1-FDX is dissociated when the CV is fully assembled. This study provides insights into the dual-function of CI-FDX in CI and CV assembly, facilitating the understanding of the CI and CV assembly mechanism in plants. [ABSTRACT FROM AUTHOR]

The objective of this paper is to analyze the relationship between working poverty and informality, based on the Argentine case of the last two decades. We examine the net effect of labor informality on monetary poverty and under which labor, socio-demographic, and family conditions informality is more strongly associated with poverty. We use micro data from the National Institute of Statistics and Censuses' (indec) Permanent Household Survey and apply microsimulations and multivariate analysis. The results show that informality is a structural component of the urban labor market and that the net effect of informality is relevant and sustained over time. However, they also reveal that the relationship between informality and poverty is not straightforward: most informal insertions are not directly linked to economic deprivation. The risk of poverty among the informally employed is explained not only by the characteristics of their occupations, but also by sociodemographic characteristics, dependency rates in their households, and the low protective capacity of social benefits. [ABSTRACT FROM AUTHOR]

Mitoribosome biogenesis is a complex process involving RNA elements encoded in the mitochondrial genome and mitoribosomal proteins typically encoded in the nuclear genome. This process is orchestrated by extra‐ribosomal proteins, nucleus‐encoded assembly factors, which play roles across all assembly stages to coordinate ribosomal RNA processing and maturation with the sequential association of ribosomal proteins. Both biochemical studies and recent cryo‐EM structures of mammalian mitoribosomes have provided insights into their assembly process. In this article, we will briefly outline the current understanding of mammalian mitoribosome biogenesis pathways and the factors involved. Special attention is devoted to the recent identification of iron–sulfur clusters as structural components of the mitoribosome and a small subunit assembly factor, the existence of redox‐sensitive cysteines in mitoribosome proteins and assembly factors, and the role they may play as redox sensor units to regulate mitochondrial translation under stress. [ABSTRACT FROM AUTHOR]

Asphalt, as a key binder material in road construction, is susceptible to ultraviolet (UV) radiation-induced aging, leading to embrittlement and reduced durability. Despite the significance of UV aging, research in this area remains limited compared to that on thermal aging. This paper comprehensively reviews the current state of research on UV aging in asphalt, focusing on its mechanism, evaluation indicators, and methods to delay or avoid UV aging. The structural components, rheological properties, and aging mechanisms of asphalt are discussed. Various UV aging simulation methods, including the use of UV chambers and accelerated aging tests, are presented along with their evaluation tests such as dynamic shear rheometry, rutting tests, Fourier infrared spectroscopy, and bending beam rheology. Key indicators used to assess UV aging, including physical properties, rheological parameters, and chemical composition changes, are summarized. The mechanisms underlying UV aging, particularly the changes in asphalt's structural components and rheological properties, are examined. The impact of factors like radiation intensity, temperature, chemical composition, and asphalt film thickness on UV aging is discussed. Additionally, various additives and modifiers, including modified bitumen, UV shielding agents, UV absorbers, antioxidants, and nanomodifiers, are reviewed for their potential to mitigate UV aging. This paper concludes by highlighting the challenges in developing standardized test equipment and evaluation criteria, the limitations of organic modifiers, and the need for further research on nanomaterials to improve asphalt's UV aging resistance. [ABSTRACT FROM AUTHOR]

Traditional and modern coatings play a key role in enhancing the fire resistance of ancient Chinese buildings. However, further comparative analysis is needed on the fire properties of the two coatings and their effects on different timber structural components. This study focuses on the main hall of the Shanxi Changzhi Xianqing Temple, a typical traditional column and beam construction built between the Song and Jin periods. Firstly, the combustion characteristics of various timber structural component samples with different surface treatments (traditional "Yi-ma-wu-hui" and modern flame retardants) were analyzed using cone calorimeter. Secondly, the fire development process of the Xianqing Temple building model was analyzed by a fire dynamics simulator (FDS), and the effect mechanism of different surface treatments on the burning process was further studied. The results show that the fire resistance of timber structural components is significantly improved after modern and traditional surface treatments. The traditional method is more effective in delaying the peak heat release rate and reducing the surface temperature during combustion, while the modern surface treatment significantly prolongs the ignition time of the timber structural components. The FDS results confirm that modern and traditional surface treatments significantly improve the fire resistance of the building, delaying the flashover time by about 300 s, with no collapse occurring within 800 s. In addition, the fire resistance of buildings after traditional surface treatment is better compared to traditional methods. The above research results can provide direct data support for the selection and optimization of fireproof coatings and treatment methods for ancient buildings. [ABSTRACT FROM AUTHOR]

Specific leaf area (SLA) plays a critical role in carbon assimilation and nutrient cycling. While leaf habit (deciduous vs. evergreen) has often been recognized as a reliable predictor of SLA—with deciduous species typically having higher mean SLA values due to lower concentration of structural components compared to evergreens—high variation in SLA among evergreen species suggests further investigation of variation for species with this leaf habit could improve predictions of SLA effects on community and ecosystem processes. Furthermore, the presence of leaves of different ages in evergreen plants, emerging over multiple years, could amplify the within-individual variation in SLA, which remains underexplored. Here we report variations of SLA measured from c. 2000 leaves collected from 36 individuals across 19 woody species in an understory environment in New Zealand (NZ). We found that while most deciduous species, predominantly non-native, clustered towards higher SLA values, evergreen species presented a wide SLA spectrum. Moreover, we found that while being deciduous, having a smaller leaf size, and younger leaves, collected from lateral branches, correlated with elevated SLA values, the leaf habit did not primarily drive the within-individual SLA variation. Instead, smaller leaf size emerged as a significant predictor of within-individual SLA variation. The branch-order effect on SLA underscores a methodological consideration: accurate estimation of total leaf area in evergreen trees requires representative sampling across all branch orders. Our study also highlights the need for integrating leaf traits such as leaf size and branch order into functional trait analyses. Further research is vital to understand the underlying mechanisms of these trait variations and their impacts on ecosystem functioning. [ABSTRACT FROM AUTHOR]

Segmentation of structural components in infrastructure inspection images is crucial for automated and accurate condition assessment. While deep neural networks hold great potential for this task, existing methods typically require fully annotated ground truth masks, which are time‐consuming and labor‐intensive to create. This paper introduces Scribble‐supervised Structural Component Segmentation Network (ScribCompNet), the first weakly‐supervised method requiring only scribble annotations for multiclass structural component segmentation. ScribCompNet features a dual‐branch architecture with higher‐resolution refinement to enhance fine detail detection. It extends supervision from labeled to unlabeled pixels through a combined objective function, incorporating scribble annotation, dynamic pseudo label, semantic context enhancement, and scale‐adaptive harmony losses. Experimental results show that ScribCompNet outperforms other scribble‐supervised methods and most fully‐supervised counterparts, achieving 90.19% mean intersection over union (mIoU) with an 80% reduction in labeling time. Further evaluations confirm the effectiveness of the novel designs and robust performance, even with lower‐quality scribble annotations. [ABSTRACT FROM AUTHOR]

Under the background of dual carbon policy as well as energy conservation, blanks with variable thicknesses (BVTs) which act as structural components have drawn extensive attention due to their excellent strength and formability and reasonable load-bearing distribution characteristics, particularly in the field of automotive manufacturing. With these advantages, the manufacturing technologies of these plates using more efficient rolling methods have thus emerged. This article summarizes four methods and their characteristics for manufacturing plates with variable thicknesses based on rolling technology. In addition, a review is conducted on the latest research progress of the metal flow and rolling theories of existing plates with different thicknesses in the longitudinal and transverse direction. [ABSTRACT FROM AUTHOR]

Underground parking garages are enclosed spaces not directly exposed to the exterior. A smoke control system is typically required to facilitate occupants’ safe evacuation/relocation and assist in firefighting/rescue. Currently, there is a lack of guidelines for designing such systems in primary codes/standards. Only a limited number of local authorities have developed amendments to address this issue. These amendments either rely on outdated approaches, such as air change method, or simply repurpose carbon monoxide ventilation systems for smoke control without conducting additional engineering analysis and providing justification. The intent of this study is to examine the adopted approaches and explore an effective and efficient approach for garage smoke control. According to the study’s findings, it is discovered that garage floor height significantly impacts the performance of smoke control system. Additionally, structural components (beams) also influence the performance of smoke control system. Moreover, this study derives a linear equation to ascertain available safe egress time (ASET) when utilizing the carbon monoxide ventilation system or typical air change methods. Taking cost into consideration, the study concludes that for effective and cost-efficient smoke control in large underground garages, employing a carbon monoxide ventilation system is preferable to the traditional or equivalent air change method. [ABSTRACT FROM AUTHOR]

Current single-view image inpainting methods often suffer from low image information utilization and suboptimal repair outcomes. To address these challenges, this paper introduces a novel image inpainting framework that leverages a structure-guided multi-scale attention pyramid network. This network consists of a structural repair network and a multi-scale attention pyramid semantic repair network. The structural repair component utilizes a dual-branch U-Net network for robust structure prediction under strong constraints. The predicted structural view then serves as auxiliary information for the semantic repair network. This latter network exploits the pyramid structure to extract multi-scale features of the image, which are further refined through an attention feature fusion module. Additionally, a separable gated convolution strategy is employed during feature extraction to minimize the impact of invalid information from missing areas, thereby enhancing the restoration quality. Experiments conducted on standard datasets such as Paris Street View and CelebA demonstrate the superiority of our approach over existing methods through quantitative and qualitative comparisons. Further ablation studies, by incrementally integrating proposed mechanisms into a baseline model, substantiate the effectiveness of our multi-view restoration strategy, separable gated convolution, and multi-scale attention feature fusion. [ABSTRACT FROM AUTHOR]

Rolling stock manufacturers are finding innovative structural solutions to improve the quality and reliability of railway vehicle components. Structural optimization processes represent an effective strategy for reducing manufacturing costs, resulting in geometries that are easier to design and produce combined with innovative materials. In this framework, the present paper proposes the development of a design methodology to innovate a railway bolster beam using topological optimization techniques, assessing the effect of different manufacturing constraints oriented to the casting process. A comprehensive numerical testing campaign was conducted to establish an effective testing procedure. Two different designs were obtained and compared, statically and dynamically, evaluating the difference in terms of mass, mechanical performance and manufacturability. Reductions in stress values up to 70% were observed, along with an 8% increase in the first natural frequency of the component, leading to beneficial effects in terms of stiffness. The methodology shows encouraging results to streamline the design of complex casting components, moving to a new generation of structural railway components. [ABSTRACT FROM AUTHOR]

A composite multifunctional radar absorption polymethacrylimide (RAPMI) foam sandwich (MRAPS) was constructed. Analytical models for out-of-plane and in-plane compression of the MRAPS were established. Three-dimensional failure mechanism maps and specific strength cubic cloud maps were drawn. Finally, a multiobjective particle swarm optimization (MOPSO) algorithm was used to achieve an integrated design, and a specific calculation example was tested and verified through experiments. The resulting sandwich with a 43.0 mm thickness core and 0.13 g/cm3 density achieves 90% effective absorption above broadband (RL ≤ −10 dB) in the 2–18 GHz range. As a radar absorption absorber, the MRAPS increased the engineering value and strategic importance of PMI foam for structural components in the military and aerospace sectors. [ABSTRACT FROM AUTHOR]

Polymers have emerged as a novel class of engineered materials that find application in several domains, such as structural components, fittings, couplings, and more. Due to their viscoelastic nature, these materials experience a deformation dependent on time when subjected to an applied load. This paper presents a novel approach to address this research gap by introducing simplified and practical models for predicting creep and back creep displacement utilizing a non-destructive technique, specifically micro-indentation. A comprehensive experimental investigation of multi-cycle indentation testing has been conducted. The creep and back creep models that have been developed are expressed as nonlinear exponential equations, which include variables such as material properties determined using micro-indentation techniques, as well as experimental parameters like maximum load, loading and unloading rates, and the indenter's hold time. The relationships discussed significantly influence the holding time at maximum and minimum loading conditions. One advantage of these exponential models is their ability to provide a simple mathematical representation. By utilizing this approach, there is no longer a requirement to conduct multiple single-cycle indentations or to depend only on conventional creep tests. [ABSTRACT FROM AUTHOR]

The different approximating assumptions used in deriving models for structural analysis by dimensional reduction of a 3d continuum to structural components like beams and plates or shells limit the applicability of these models by geometrical constraints. Hence, caution should be exercised when transitioning from the application range of one type of structure model to another one. This should be taken into account especially when stability analyses are performed. In order to demonstrate this, in this note, buckling of annular plates under tensile loading at the inner edge is treated as an example. The ratio between inner and outer radius is varied. For ratios approaching 1.0, plate buckling turns into buckling of circular beams. This is not only a question of accuracy of the solution but can lead to a substantial qualitative change of the character of buckling. Such considerations might be interesting from a theoretical point of view; in any case they are important from the engineering point of view. [ABSTRACT FROM AUTHOR]

Existence of global attractors for a structural-acoustic system, subject to restricted boundary dissipation, is considered. Dynamics of the acoustic environment is given by a linear 3-D wave equation subject to locally distributed boundary dissipation, while the dynamics on the (flat) structural wall is given by a 2D-Kirchhoff-Boussinesq plate equation, subject to linear dissipation and supercritical nonlinear restoring forces. It is shown that the trajectories of the dynamical system defined on finite energy phase space are attracted asymptotically to a global attractor. The main challenges of the problem are related to: (i) superlinearity of the elastic energy of the structural component, (ii) Boussinesq effects of internal forces potentially leading to a finite time blowing up solutions, (iii) partially-restricted boundary dissipation placed on the interface only. The resulting system lacks dissipativity along with the suitable compactness properties, both corner stones of PDE dynamical system theories [1]. To contend with the difficulties, a new hybrid approach based on a suitable adaptation of the so called "energy methods" [2-3] and compensated compactness [4] has been developed. The geometry of the acoustic chamber plays a critical role. [ABSTRACT FROM AUTHOR]

The structural resolution describes the ability of a measuring device to detect small structures on the surface of a component or test specimen by means of a quantitative value. However, the structural resolution in the computer tomograph depends on the object and must therefore be determined separately for each measurement task. The previous approaches to structural resolution determination are only related to test specimens. In this paper, less discrete approaches based on a circular pattern are presented, which can be integrated into the measured component. A voxel-based methodology as well as two surface-based methodologies are described. The investigation results regarding the effect of the component position on the structural resolution are obtained on the basis of real CT measurements. A comparison is also completed with the well-known hourglass method. The results show that the resolution depends on the object being measured, with similar values being obtained for the same object using different methods. [ABSTRACT FROM AUTHOR]

The mean stress effect remains a critical aspect in multiaxial fatigue analysis. This work presents a new criterion that, based on the classical Findley criterion, applies a material-dependent exponent to the mean normal stress term and includes the ultimate tensile stress as a fitting parameter. This way of considering the non-linear effect of the mean stress, with a material-dependent rather than a fixed exponent, is totally innovative among the multiaxial fatigue criteria found in the literature. In order to verify its accuracy, the new criterion has been checked against an extended version of the Papuga database of multiaxial experimental tests with 485 results, and compared with the criteria by Findley, Robert, and Papuga. The new criterion provides outstanding results for pure uniaxial cases, with multiaxial performance similar to the Robert criterion with a smaller range of error and a conservative trend, even surpassing the popular Papuga method in several relevant loading scenarios. These features enhance the applicability and versatility of the criterion for its use in the fatigue design of structural components. [ABSTRACT FROM AUTHOR]

Throughout their lifetimes, bridges are exposed to various forces that may lead to displacement and deformation, potentially compromising their structural integrity. Monitoring their structural integrity under environmental factors is essential for safety and maintenance under these conditions. This aspect is a fundamental component of Structural Health Monitoring (SHM). Many studies focus on Structural Health Monitoring (SHM), employing various theories, methodologies, and technologies that have advanced rapidly due to the expansion of information technology. The objective of this study is to pinpoint areas where research is lacking in the existing literature on the environmental factors that impact the displacement of bridges, along with the techniques and technology used to monitor these structures. To achieve this objective, the most critical environmental factors and technologies, particularly those that are sensor-based, have been identified through a systematic search of the most popular databases. Subsequently, the study utilized a bibliometric analysis, exploring the challenge and prospective research areas reflected in the specialized literature. The findings indicate a lack of scholarly investigation of environmental factors that influence the Structural Health Monitoring (SHM) of bridges, in particular studies regarding the effect of uneven sunlight on structures. The research provides a comprehensive understanding of the Structural Health Monitoring (SHM) of bridges and has practical implications for developing effective monitoring methodologies. [ABSTRACT FROM AUTHOR]

This study discusses the seismic performance evaluation of an irregular auditorium building. The building is an educational facility which has roof span up to 46 meters, column height up to 10 meters, beam span up to 15 meters, cantilever up to 6.50 meters, 2 inclined columns with the angle up to 54.72°, and 1 transfer column with 1 transfer beam. The evaluation process was carried out using Tier 3 method with linear dynamic procedure which consisted of Response Spectrum Analysis (RSA) and Linear Time History Analysis (LTHA) according to ASCE 41-23 using SAP2000 subjected to short (Ss) and long (S1) period of earthquakes. The building is designed to Risk Category IV, which the target performance levels for structural components are Immediate Occupancy (IO) for Basic Safety Earthquake 1 for New Building (BSE-1N) and Life Safety (LS) for Basic Safety Earthquake 2 for New Building (BSE-2N). Even though the building had a torsional strength irregularity, the percentage of components with a Demand-Capacity Ratio value that did not meet the requirements was 9.87% of the total components; hence the linear procedure was assumed to be still applicable. Analyses showed that the average acceptance criteria ratio of the components with the RSA method was lower than with the LTHA method but the percentage of the components with acceptance criteria ratio exceeding 1 using RSA method was higher than using the LTHA method. In addition, the results indicated that the average performance level of the components was IO for BSE-1N and LS for BSE-2N, which both results had met the expected performance level targets. However, the maximum performance level of the components did not meet the IO performance level target for BSE-1N and did not meet the LS performance level target for BSE-2N. [ABSTRACT FROM AUTHOR]

Describing an object from multiple perspectives often leads to incomplete data representation. Consequently, learning consistent representations for missing data from multiple views has emerged as a key focus in the realm of Incomplete Multi-view Representation Learning (IMRL). In recent years, various strategies, such as subspace learning, matrix decomposition, and deep learning, have been harnessed to develop numerous IMRL methods. In this article, our primary research revolves around IMRL, with a particular emphasis on addressing two main challenges. Firstly, we delve into the effective integration of intra-view similarity and contextual structure into a unified framework. Secondly, we explore the effective facilitation of information exchange and fusion across multiple views. To tackle these issues, we propose a deep learning approach known as Structural Contrastive Auto-Encoder (SCAE) to solve the challenges of IMRL. SCAE comprises two major components: intra-view structural representation learning and inter-view contrastive representation learning. The former involves capturing intra-view similarity by minimizing the Dirichlet energy of the feature matrix, while also applying spatial dispersion regularization to capture intra-view contextual structure. The latter encourages maximizing the mutual information of inter-view representations, facilitating information exchange and fusion across views. Experimental results demonstrate the efficacy of our approach in significantly enhancing model accuracy and robustly addressing IMRL problems. The code is available at https://github.com/limengran98/SCAE. [ABSTRACT FROM AUTHOR]

This study investigates the performance of a multilayered packed-bed active magnetic regenerator (AMR) using spheroidal particles with first-order magnetocaloric properties. The hydraulic performance is assessed via the interstitial friction factor, showing significant underestimation by the Ergun Equation at high mass flow rates. Coefficient adjustments are made to accurately represent the AMR pressure drop, considering particle nonuniformity and structural components, such as layer mesh dividers. This facilitates the pressure drop modeling and provides a means to check the AMR integrity on a routine basis, without requiring AMR disassembly. The thermal performance, evaluated in terms of the regenerator effectiveness, shows a satisfactory cooling potential for practical applications but emphasizes the need for flow control to prevent effectiveness imbalance between hot and cold flows, crucial for optimal operation. The cooling capacity and maximum temperature span are also evaluated, demonstrating that higher mass flow rates yield higher cooling capacities with lower temperature spans, while lower rates achieve higher spans. Varying the blow fraction shows that regenerators at 50% blow fraction achieve 10% higher cooling capacities than at 37.5%. Increasing operational frequency improves cooling by increasing the number of cycles and reducing losses, resulting in a 15% capacity increase between 0.25 and 0.50 Hz. However, this trend may reverse at higher frequencies beyond the experimental limits. While this study improves the understanding of the hydraulic and thermal performance of packed-bed AMRs, its findings underscore the importance of flow balance and frequency in achieving optimal performance, thus providing insights for future system improvements. • A 233.5-g 10-layer packed-bed AMR made from commercial La–Fe–Si is investigated. • Passive tests yielded regenerator effectiveness above 95% with little flow imbalance. • A non-invasive test of AMR bed integrity using cumulative pressure drop is proposed. • At 0.75 Hz, a maximum (zero-span) cooling capacity of 22 W was obtained. • At 0.5 Hz, a maximum (zero-capacity) temperature span of 24 °C was obtained. [ABSTRACT FROM AUTHOR]

This study investigates the development and characterization of a novel composite material for structural applications, aiming to address the growing demand for lightweight, durable and versatile materials. The composite integrates aramid fibre reinforced with sawdust particulates within an epoxy matrix. Methodologically, the composite was fabricated using a hand layup process, ensuring even distribution and strong adhesion between components. Mechanical testing revealed significant enhancements in tensile strength (up to 135.29 MPa) and flexural strength (up to 136.92 MPa) with the inclusion of sawdust particulates, optimizing stress distribution and impact resistance. Hardness was also improved, peaking at a Rockwell hardness number of 94. Thermal analysis demonstrated moderate thermal conductivity (1.92 W mK−1) and a high heat deflection temperature (109 °C), indicating excellent thermal stability. SEM provided insights into the composite's microstructure, confirming uniform sawdust distribution and robust fibre–matrix adhesion. These findings underscore the potential of this composite for lightweight, durable and thermally stable structural applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Summary: Cracks can develop in high‐rise buildings because of long‐term environmental changes and extreme loading events such as strong winds or earthquakes. Although deep learning‐based identification methods can efficiently identify cracks, the accuracy of crack identification in high‐rise buildings needs to be improved due to the lack of crack datasets specifically related to high‐rise structures. Moreover, the number of available images of cracks in high‐rise is limited. To this end, this paper establishes an intelligent crack identification method based on a photorealistic synthetic modeling technique. First, a computer graphics (CG) model of a high‐rise building with assumed damage is constructed. Subsequently, the CG model is utilized to generate a dataset that includes photorealistic images of the high‐rise building as well as corresponding labels for various components and types of damage. The generated dataset is then used to train a DeepLabv3 + neural network for structural component and damage identification, followed by validation by employing images of both synthetic and full‐scale high‐rise buildings. The trained network can accurately identify different components in images of the full‐scale, high‐rise building and identify cracks that are intentionally synthesized in those images. The results show that the synthetic dataset generated by the CG model not only allows for fast and efficient labeling for the purpose of neural network training but also outperforms methods that do not consider any application‐specific context in crack identification. [ABSTRACT FROM AUTHOR]

Material extrusion (MEX) is worldwide known as one of the most flexible additive manufacturing (AM) technologies for the fabrication of complex polymeric structures. However, the extremely high geometrical freedom has a price to pay: the presence of interlayer voids between consecutive extruded layers is the main backwards of MEX technology. Interlayer voids make 3D printed parts weaker (poor mechanical properties) compared to polymeric components fabricated by means of counterpart processes (i.e., injection molding). The present research work introduces a novel approach for the reduction of voids based on the layer-by-layer application of solvent vapor during the fabrication process, to smooth every single deposited layer. In this way, the new extruded layer has a greater area to bond with the previously extruded layer, resulting in an overall reduction of the porosity. The proposed approach is cost-effective, and it is based on the stop and go method enabled by MEX technologies: the fabrication process is paused after every layer, and when the solvent treatment is performed, the 3D printing process is resumed. The effectiveness of the layer-by-layer solvent vapor approach was evaluated, thereby resulting in a great reduction of the void density and average void area of 96%, and 79% respectively, and an increase of the wetting factor of 34%. Such findings pave the way for the exploitation of the proposed approach for the fabrication of complex structures with a reduced number of voids to be employed as structural components. [ABSTRACT FROM AUTHOR]

Impact-oscillatory loading of variable intensity was applied to the VT23M high-strength sheet two-phase titanium alloy in liquid nitrogen. This was carried out to investigate the effect of this loading type on changes in the mechanical properties and structural condition of the alloy upon subsequent static tensioning at normal temperature. Dynamic non-equilibrium process (DNP) realized at a temperature of liquid nitrogen proved to be unable to impair the strength properties of the VT23M titanium alloy compared to room temperature; however, they caused a significant decrease in ductility (down to 16%). The impaired plastic properties of the alloy were shown to entail additional defects in the structural components of the alloy. The authors have found patterns of damage accumulation in the structural components of the alloy depending on the DNP parameters. They are in good agreement with the findings of the fractographic research. [ABSTRACT FROM AUTHOR]

Although the Hepatitis E virus (HEV) is an emerging global health burden, little is known about its interaction with the host cell. HEV genome encodes three proteins including the ORF2 capsid protein that is produced in different forms, the ORF2i protein which is the structural component of viral particles, and the ORF2g/c proteins which are massively secreted but are not associated with infectious material. We recently demonstrated that the endocytic recycling compartment (ERC) is hijacked by HEV to serve as a viral factory. However, host determinants involved in the subcellular shuttling of viral proteins to viral factories are unknown. Here, we demonstrate that the AP-1 adaptor complex plays a pivotal role in the targeting of ORF2i protein to viral factories. This complex belongs to the family of adaptor proteins that are involved in vesicular transport between the trans-Golgi network and early/recycling endosomes. An interplay between the AP-1 complex and viral protein(s) has been described for several viral lifecycles. In the present study, we demonstrated that the ORF2i protein colocalizes and interacts with the AP-1 adaptor complex in HEV-producing or infected cells. We showed that silencing or drug-inhibition of the AP-1 complex prevents ORF2i protein localization in viral factories and reduces viral production in hepatocytes. Modeling of the ORF2i/AP-1 complex also revealed that the S domain of ORF2i likely interacts with the σ1 subunit of AP-1 complex. Hence, our study identified for the first time a host factor involved in addressing HEV proteins (i.e. ORF2i protein) to viral factories. [ABSTRACT FROM AUTHOR]

During the transition towards sustainable practices, cork has emerged as a pivotal material. Its distinctive cellular structure and chemical composition, encompassing suberin, lignin, cellulose, and extractives, underpin a multitude of properties. The honeycomb arrangement of cells confers upon cork advantages such as lightweightness, insulation, thermal regulation, and remarkable mechanical performance. Breakthroughs in nanotechnology have enabled precise modifications, broadening the scope of cork's applications beyond conventional uses. This review offers a comprehensive exploration of cork's natural structure and composition, with a focus on its intricate cellular arrangement and specialized suberin components. It elucidates the intricate interplay between cork's structure and properties, evaluating modification strategies and lifecycle impacts. Furthermore, the discussion extends to the realm of functional polymers and structural components derived from cork, underscoring the potential for designing eco-friendly materials. Ultimately, this review aims to catalyze future research endeavors geared towards the sustainable utilization of cork in tackling global challenges, emphasizing the crucial nexus between structure, assembly, and function. [ABSTRACT FROM AUTHOR]

Argumentation is a scientific practice that can be developed through specific training within the framework of socio-scientific issues, for which Toulmin's Argument Pattern (TAP) is a privileged logical and dialectical instrument. In a design-based research, we sought to contribute to a biodiversity education that plays a role in positioning and decision-making on problems that link its components with the structural and functional characteristics of local ecosystems. The results were analyzed from the data obtained in the final phase and show progress in the conceptual knowledge of biodiversity and, in addition, of native plants and animals, although the valuation of biodiversity components indicates the persistence of a species- and treecenteredness. Students elaborated TAP schemes but with difficulty in mobilizing information from Cartesian graphs with scientific evidence and for the rebuttals and warrants of TAP. The findings reveal that this type of didactic intervention offers aids for the development of the knowledge and skills involved, and corroborate the interest of science education in argumentation on socio-scientific issues as an epistemic practice. [ABSTRACT FROM AUTHOR]