Network Formation Research Articles

Influence of grain boundary segregation on the deformation behavior of nanocrystalline Ni50Co50 solid solution alloys investigated by molecular dynamics simulations

Molecular dynamics simulations were carried out to investigate the tensile deformation behavior of Ni50Co50 solid solution nanocrystalline alloys with varying degrees of grain boundary segregation. A comprehensive analysis disclosed that the observed strengthening in the Ni-rich grain boundary model is primarily due to the formation of Lomer-Cottrell locks and dislocation networks which impede dislocation motion. Plastic deformation, on the other hand, is predominantly governed by enhanced grain boundary migration, grain rotation, and deformation twinning. In the Co-rich grain boundary model, the interactions among twins, dislocations, and grain boundaries, stemming from the formation of extensive stacking faults and twinning, dictate the plastic deformation and strengthening. Fluctuations in grain boundary composition promote stress concentration, thereby facilitating plastic deformation and dislocation accumulation within the grain, which in turn enhances strain hardening. The study reveals that the Ni50Co50 solid solution nanocrystalline alloys exhibit both high tensile strength and favorable plasticity for models with grain boundary segregation around ±10%. These insights provide valuable guidance for the development of Ni50Co50 nanocrystalline alloys with optimized strength and toughness.

Insights into the ternary substitution Na2.96+xK0.04 V2-xNix(PO4)2.98F0.06 with superior rate capability and near-zero strain property

Na3V2(PO4)3 (NVP) is considered the most favorable cathode for sodium-ion batteries due to its solid NASICON skeleton. Nevertheless, poor intrinsic conductivity is insufficient for its further commercialization. In this paper, we present a promising K/Ni/F co-doped and carbon nanotubes (CNTs) encapsulated Na2.96+xK0.04 V2-xNix(PO4)2.98F0.06 (KNF@CNTsx) cathode materials. The synthesis of KNF@CNTsx is achieved using a facile sol-gel method. The replacement of Na+ with K+ broadens the migratory pathway and supports the crystal skeleton, while F− substitution reduces the average grain dimension, thereby increasing the diffusion rate of Na+. Furthermore, the reduction of resistance by Ni2+ doping enables optimization of the transport of electrical charge, while also facilitating the optimization of chemically-defined properties. Concurrently, the optimal quantity of carbon capping and wrapping of CNTs facilitate the formation of efficacious conductive network, which diminishes the size of grains and shortens the pathway for the diffusion of Na+. This network could also serve as a buffer against crystal deformation. In conclusion, the modified KNF@CNTsx samples exhibit notable enhancements in their conductivity, ion diffusion capacity, and structural stability. Among them, the KNF@CNTs0.04 sample exhibits a capacity for reversibility of 93.3 mAh g−1 at 50C, with a remaining capacity of 68.5 mAh g−1 after 4000 successive long charge-discharge cycles. Ex-situ electrochemical XRD demonstrates the V3+/V4+ redox reaction occurs accompanied by the phase transfer reaction, during which Na+ prefers to diffuse along c-axial in the crustal structure. Moreover, volume alteration of this KNF@CNTs0.04 cellular entity is miniscule and reversible during the charge-discharge process, further confirming the stabilized construction and near-zero strain property. The after-cycled XRD/SEM/XPS certify the improved chemical and structural stability of KNF@CNTs0.04, indicating the constructive effects of K/Ni/F ternary substitution.

Continuous Phase Separation Induced Tough Hydrogel Fibers with Ultrahigh Conductivity for Multidimensional Soft Electronics

AbstractConductive hydrogel fibers exhibit great potential in soft robots, bioelectronics, and human–machine interfaces due to the unique combination of electrical conductivity, high water content, tissue‐like mechanical properties, and 1D structure. Despite significant advances in hydrogel technologies, the typical conductive hydrogel fibers show low conductivity (<10 S cm−1), weak mechanical properties, and water stability, which makes it challenging to satisfy the requirements of practical applications. Here, a facile strategy is proposed to construct hydrogel fibers with ultrahigh conductivity and toughness by exploiting the synergistic effects of freezing‐thawing, salting‐out, and drying‐annealing. The continuous phase separation induced by the combined processes results in hierarchical structures, promoting the formation of interconnected conductive networks and increasing the fiber's crystallinity and crystal domain size. The prepared conductive hydrogel fibers exhibited ultrahigh conductivity (≈958 S cm−1), excellent mechanical properties (strength (≈6.2 MPa), stretchability (>300%), and toughness (≈10 MJ m−2)), high water content (≈75%), outstanding water stability, and fatigue resistance properties. In addition, the processibility of conductive hydrogel yarns and fabrics are demonstrated and their potential application in bioelectronics. Overall, this work presents a preparation strategy for conductive hydrogel fibers, which will facilitate the advancement of soft electronics and may inspire structural construction in other polymers.

In Situ Constructing Robust Interface by Deep Eutectic Polymeric Electrolyte Enables High Performance Lithium Metal Batteries with High-Loading Cathode.

The low Li+ transport and poor interface have consistently been two major impediments to practical applications of Polyacrylonitrile (PAN)-based composite solid-state electrolytes (PCPE). In this work, a polymerizable deep eutectic electrolyte is meticulously designed with high fluidity which consists of Poly (Ethylene Glycol) Diacrylate (PEGDA), Fluoroethylene Carbonate (FEC), Succinonitrile (SN) and dual salts (LiTFSI/LiDFOB) to promote Li+ transport and ameliorate the interface of PCPE. Inclusion of PEGDA monomers and FEC alters the crystallinity of SN, enhancing the wettability of thick electrode, and formation of polymeric 3D network from polymerization of PEGDA can anchor SN and suppress the side reactions between SN and lithium metal. Consequently, the modified PCPE exhibit an enhanced conductivity of 4.47×10-4Scm-1 with Li-ion transference number of 0.60, and show an excellent lithium stability. LiCoO2(LCO)/SP-PCPE/Li batteries with higher loading (3-4.4V, 6mgcm-2) can work for over 300 cycles at 0.5 C. Even with an ultra-high loading of 16mgcm-2, LCO/SP-PCPE/Li batteries achieve an excellent cycling performance. This work provides new insights into how to construct a robust interface for solid-state batteries with high-loading cathode.

Networks rewired: quota enforcement and the unintended mobilization of native place ties

Abstract We explore how institutional designs can have unintended consequences, especially by rewiring social networks. Using archival data on the civil-service examinations in historical China, we argue that the enforcement of a regional quota system in 1427 reshaped group boundaries along native place, turned emotional affinities for one’s hometown into political stakes, and reinforced the influence of native place ties among political elites. Analyzing approximately 30,000 individual records, we confirm this argument by documenting a macro-level shift from a highly unequal to a more balanced provincial distribution of students who passed the examinations following the enforcement of the quota system. As native place became a primary basis for network homophily, elites deliberately cultivated these connections, seizing the opportunity as ad hoc examiners to provide preferential treatment based on shared place of origin. Our micro-level analysis of 12,752 passing students between 1400 and 1580 identifies this in-group favoritism, with examiners often ranking students from their own provinces higher. A mechanism of safeguarding political stakes underscores this baseline effect, which became more pronounced during the quota stage, especially under weaker state capacity, among examiners from disadvantaged provinces, and when examiners had greater vested interest in their hometown. These findings enrich theories of group boundaries and categorization, network homophily and formation, and the unintended consequences of institutional designs while also providing policy insights for affirmative action.

Design and Control of Polymeric Network Architectures Based on Network Dimension Theory

AbstractA new design policy to synthesize nanogel molecules having desired dimensions under unperturbed state is proposed. Miniemulsion copolymerization of vinyl and divinyl monomers, both conventional free‐radical polymerization and ideal living polymerization, is used to illustrate the method. For the network formation dynamics, the newly proposed model that takes into account the size and structure dependence of cross‐linking/cyclization reactions is employed. The master curve relationship that indicates the maximum average dimensions for randomly cross‐linked networks is used as a guideline and the network dimension is controlled by the magnitude of network maturity index NMI, which is the average number of cycle rank per primary chain. By appropriately sizing the NMI, it is possible to synthesize network polymers with dimensions equal to or greater than the maximum dimensions achievable with a homogeneous, randomly cross‐linked network polymer of the same cycle rank and molecular weight. The current strategy of designing and controlling 3D size is applicable regardless of the reaction mechanism of network formation and will also be applied to the synthesis of macro‐gels.

Improving the Gelation Properties of Pea Protein Isolates Using Psyllium Husk Powder: Insight into the Underlying Mechanism

The industrial application of pea protein is limited due to its poor gelation properties. This study aimed to evaluate the effects of psyllium husk powder (PHP) on improving the rheological, textural, and structural properties of heat-induced pea protein isolate (PPI) gel. Scanning electron microscopy (SEM), intermolecular forces analysis, the quantification of the surface hydrophobicity and free amino groups, and Fourier transform infrared spectroscopy (FTIR) were conducted to reveal the inner structures of PPI-PHP composite gels, conformational changes, and molecular interactions during gelation, thereby clarifying the underlying mechanism. The results showed that moderate levels of PHP (0.5–2.0%) improved the textural properties, water holding capacity (WHC), whiteness, and viscoelasticity of PPI gel in a dose-dependent manner, with the WHC (92.60 ± 1.01%) and hardness (1.19 ± 0.02 N) peaking at 2.0%. PHP significantly increased surface hydrophobicity and enhanced hydrophobic interactions, hydrogen bonding, and electrostatic interactions in PPI-PHP composite gels. Moreover, the electrostatic repulsion between anionic PHP and negatively charged PPI in a neutral environment prevented the rapid and random aggregation of proteins, thereby promoting the formation of a well-organized gel network with more β-sheet structures. However, the self-aggregation of excessive PHP (3.0%) weakened molecular interactions and disrupted the continuity of protein networks, slightly reducing the gel strength. Overall, PHP emerged as an effective natural gel enhancer for the production of pea protein gel products. This study provides technical support for the development of innovative plant protein-based foods with strong gel properties and enriched dietary fiber content.

Hierarchical structure Fe@CNFs@Co/C elastic aerogels with intelligent electromagnetic wave absorption

AbstractDeveloping intelligent electromagnetic wave (EMW) absorption materials with real‐time response‐ability is of great significance in complex application environments. Herein, highly compressible Fe@CNFs@Co/C elastic aerogels were assembled through the electrospinning method, achieving EMW absorption through pressure changes. By varying the pressure, the effective absorption bandwidth (EAB) of Fe@CNFs@Co/C elastic aerogels shows continuous changes from low frequency to high frequency. The EAB of Fe@CNFs@Co/C elastic aerogels is 14.4 GHz (3.36–17.76 GHz), which covers 90% of the range of S/C/X/Ku bands. The theoretical simulation indicates that the external pressure prompts a reduction in the spacing between the fiber layers in the aerogels and facilitates the formation of a 3D conductive network with enhanced attenuation ability of EMW. The uniform distribution of metal particles and appropriate layer spacing can effectively optimize the impedance matching to achieve the best EMW absorption performance. This work state clearly that the hierarchically assembled elastic aerogels composed of metal–organic frameworks (MOFs) derivatives and carbon fibers are ideal dynamic EMW absorption materials for intelligent EMW response.image

Mobilising tensions: transnational union network formation in the Asia-Pacific region

Trade unions are an important actor in the social regulation of the transnational corporation. How and why trade unions engage with the continued rise of global corporate social responsibility (CSR) initiatives remains largely under-researched, particularly in transnational arenas beyond Europe. Transnational trade union networks are a concerted development intended to advance collective worker voice and influence, especially in contexts without a history of strong social dialogue. Our qualitative fieldwork centres on a transnational trade union network comprised of global, national, and local union representatives from different countries in the Asia-Pacific representing workers from one Germany-headquartered multinational corporation in the chemical sector. We examine how labour actors involved in the network engage with global CSR initiatives to advance worker voice and influence in the Asia-Pacific region. Our micro-sociological and relational approach focused on the practices, relations, and affective dimensions of building and sustaining a transnational network. What emerged is the centrality of tensions and how actors creatively utilise and shape those tensions into resources for building the network. We analyse the nature of the tensions and their effects and discuss how key actors work generatively with tensions.

Investigating the Role of Hub Calcification Proteins in Atherosclerosis via Integrated Transcriptomics and Network-Based Approach

Atherosclerosis (AS) is a chronic inflammatory condition of the arteries, characterized by plaque formation that can restrict blood flow and lead to potentially fatal cardiovascular events. Given that AS is responsible for a quarter of global deaths, this study aimed to develop a systematic bioinformatics approach to identify biomarkers and regulatory targets involved in plaque development, with the goal of reducing cardiovascular disease risk. AS-specific mRNA expression profiles were retrieved from a publicly accessible database, followed by differentially expressed genes (DEGs) identification and AS-specific weighted gene co-expression network (WGCN) construction. Thereafter, calcification and atherosclerosis-specific (CASS) DEGs were utilized for protein–protein interaction network (PPIN) formation, followed by gene ontology (GO) term and pathway enrichment analyses. Lastly, AS-specific 3-node miRNA feed-forward loop (FFL) construction and analysis was performed. Microarray datasets GSE43292 and GSE28829 were obtained from gene expression omnibus (GEO). A total of 3785 and 6176 DEGs were obtained in case of GSE28829 and GSE43292; 3256 and 5962 module DEGs corresponding to GSE28829 and GSE43292 were obtained from WGCN. From a total of 54 vascular calcification (VC) genes, 20 and 29 CASS-DEGs corresponding to GSE28829 and GSE43292 were overlapped. As observed from FFL centrality measures, the highest-order subnetwork motif comprised one TF (SOX7), one miRNA (miR-484), and one mRNA (SPARC) in the case of GSE28829. Also, in the case of GSE43292, the highest-order subnetwork motif comprised one TF (ESR2), one miRNA (miR-214-3p), and one mRNA (MEF2C). These findings have important implications for developing new therapeutic strategies for AS. The identified TFs and miRNAs may serve as potential therapeutic targets for treating atherosclerotic plaques, offering insights into the molecular mechanisms underlying the pathogenesis and highlighting new avenues for research and treatment.

LinkedOut? A Field Experiment on Discrimination in Job Network Formation

Abstract We assess the impact of discrimination on Black individuals’ job networks across the U.S. using a two-stage field experiment with 400+ fictitious LinkedIn profiles. In the first stage, we vary race via AI-generated images only and find that Black profiles’ connection requests are 13 percent less likely to be accepted. Based on users’ CVs, we find widespread discrimination across social groups. In the second stage, we exogenously endow Black and White profiles with the same networks and ask connected users for career advice. We find no evidence of direct discrimination in information provision. However, when taking into account differences in the composition and size of networks, Black profiles receive substantially fewer replies. Our findings suggest that gatekeeping is a key driver of Black-White disparities.

Dual Role of Ibuprofen and Indomethacin in Promoting Peripheral Nerve Regeneration In Vitro.

Peripheral nerve injuries (PNI) can result in significant losses of motor and sensory function. Although peripheral nerves have an innate capacity for regeneration, restoration of function after severe injury remains suboptimal. The gold standard for peripheral nerve regeneration (PNR) is autologous nerve transplantation, but this method is limited by the generation of an additional surgical site, donor-site morbidity, and neuroma formation at the site of harvest. Although targeted drug compounds have the potential to influence axonal growth, there are no drugs currently approved to treat PNI. Therefore, we propose to repurpose commonly used nonsteroidal anti-inflammatory drugs (NSAIDs) to enhance PNR, facilitating easier clinical translation. Additionally, calcium signaling plays a crucial role in neuronal connectivity and regeneration, but how specific drugs modulate this process remains unclear. We developed an in vitro hollow channel collagen gel platform that successfully supports neuronal network formation. This study evaluated the effects of commonly used NSAIDs, namely ibuprofen and indomethacin, in our in vitro model of axonal growth, regeneration, and calcium signaling as potential treatments for PNI. Our results demonstrate enhanced axonal growth and regrowth with both ibuprofen and indomethacin, suggesting a positive influence on PNR. Further, these drugs showed enhanced calcium signaling dynamics, which we posit is a crucial aspect for nerve repair. Taken together, these findings highlight the potential of ibuprofen and indomethacin to be used as treatment options for PNI, given their dual capability to promote axonal growth and enhance calcium signaling.

Conformational Flexibility and Net Charge are Key Determinants for the Antimicrobial Activity of Peptide Uy234 Against Multidrug-resistant Bacteria

BackgroundThe antimicrobial activity of two peptides, Uy234 derived from the venom of the scorpion Urodacus yaschenkoi and a consensus peptide QnCs-Buap, was evaluated. We tested different pathogenic bacteria: Acinetobacter baumannii, Klebsiella pneumoniae, Salmonella enterica, Bacillus subtilis, Enterococcus spp. and Staphylococcus aureus, including one methicillin resistant (MRSA) and two multidrug resistant (MDR) clinical isolates. In contrast to the QnCs-Buap peptide, Uy234 showed relevant growth inhibitory activity on A. baumannii and B. subtilis, and mostly on S. aureus strains.ObjectiveThe present research focused on elucidating the mechanism for this antibacterial activity.MethodologyWe carried out an in-depth analysis of the composition, structure, flexibility, and physicochemical properties of both peptides.ResultsWe found a crucial role of the C-terminal amide and composition in favoring the formation of a dense H-bond network in the Uy234 peptide. This H-bonding network slightly stiffens the peptide and keeps it in a preordered conformation in the aqueous phase.ConclusionsWe hypothesize that, given that Uy234 is a very short peptide (18 aa), it could have a destabilizing effect and favor micellization phenomena instead forming pores. In contrast, the QnCs-Buap peptide (13 aa), having only the positive charge at the N-terminal end and being significantly more hydrophobic and rigid, is not capable of overcoming the energy barrier to disturb the membrane. We propose that Uy234 peptide can be a scaffold to develop new derivatives with high potential against infections caused by diverse multidrug-resistant bacteria.Graphical

Endosomal membrane budding patterns in plants

Multivesicular endosomes (MVEs) sequester membrane proteins destined for degradation within intralumenal vesicles (ILVs), a process mediated by the membrane-remodeling action of Endosomal Sorting Complex Required for Transport (ESCRT) proteins. In Arabidopsis, endosomal membrane constriction and scission are uncoupled, resulting in the formation of extensive concatenated ILV networks and enhancing cargo sequestration efficiency. Here, we used a combination of electron tomography, computer simulations, and mathematical modeling to address the questions of when concatenated ILV networks evolved in plants and what drives their formation. Through morphometric analyses of tomographic reconstructions of endosomes across yeast, algae, and various land plants, we have found that ILV concatenation is widespread within plant species, but only prevalent in seed plants, especially in flowering plants. Multiple budding sites that require the formation of pores in the limiting membrane were only identified in hornworts and seed plants, suggesting that this mechanism has evolved independently in both plant lineages. To identify the conditions under which these multiple budding sites can arise, we used particle-based molecular dynamics simulations and found that changes in ESCRT filament properties, such as filament curvature and membrane binding energy, can generate the membrane shapes observed in multiple budding sites. To understand the relationship between membrane budding activity and ILV network topology, we performed computational simulations and identified a set of membrane remodeling parameters that can recapitulate our tomographic datasets.

Endothelial Beta 1 Integrins are Necessary for Microvascular Function and Glucose Uptake.

Microvascular insulin delivery to myocytes is rate limiting for the onset of insulin-stimulated muscle glucose uptake. The structural integrity of capillaries of the microvasculature is regulated, in part, by a family of transmembrane adhesion receptors known as integrins, which are composed of an α and β subunit. The integrin β1 (itgb1) subunit is highly expressed in endothelial cells (EC). EC itgb1 is necessary for the formation of capillary networks during embryonic during development and its knockdown blunts the reactive hyperemia that manifests during ischemia reperfusion. We investigated the contribution of EC itgb1 in microcirculatory function and glucose uptake with emphasis in skeletal muscle. We hypothesized that loss of EC itgb1 would impair microvascular hemodynamics and glucose uptake during insulin stimulation, creating 'delivery'-mediated insulin resistance. An itgβ1 knockdown mouse model was developed to avoid lethality of embryonic gene knockout and the deteriorating health resulting from early post-natal inducible gene deletion. Mice with (itgb1fl/flSCLcre) and without (itgb1fl/fl) tamoxifen inducible stem cell leukemia cre recombinase (SLCcre) expression at 10 days post cre induction had comparable exercise tolerance and pulmonary and cardiac functions. Using robust in vivo experimental platforms (i.e., intravital microscopy and hyperinsulinemic-euglycemic clamp), we show that itgb1fl/flSCLcre mice compared to itgb1fl/fl littermates have, i) deficits in capillary flow rate, flow heterogeneity, and capillary density; ii) impaired insulin-stimulated glucose uptake despite sufficient transcapillary insulin efflux; and iii) reduced insulin-stimulated glucose uptake due to perfusion-limited glucose delivery. Thus, EC itgb1 is necessary for microcirculatory function and to meet the metabolic challenge of insulin stimulation.

How root-grafted trees form networks: Modeling network dynamics with pyNET

Natural root grafting is a widespread phenomenon in woody plants. While previous studies have focused on the effects of reduced growth and resource exchange at the individual level, we lack an understanding of the collective behavior of groups of grafted trees and the networks they form. Here, we present pyNET, a mechanistic agent-based model designed to explore the emergence of root graft networks. We performed simulation experiments with different scenarios involving water scarcity and different cost-benefit dynamics. Costs denote the resources required to form root grafts, while benefits denote the water redistributed among trees. Our model successfully replicates observed patterns linking structural variables to network characteristics. Specifically, we were able to reproduce observed characteristics such as grafting frequency and mean group size. In particular, we find that while the network structure is naturally strongly influenced by the size of the root system, the time and resources allocated to grafting are also critical factors. pyNET serves as a valuable tool for exploring the formation of root grafting networks under diverse environmental conditions and understanding their impact on resource competition. Our study supports theory development on the subject and hopefully stimulates further empirical studies.

Development of Novel Cardanol-Derived Reactive Dispersing Agents for Bio-Based Anionic–Nonionic Waterborne Polyurethane

This study successfully developed a bio-based, photocurable, anionic–nonionic dual-functional chain extender, and sulfonated cardanol-based polyethylene glycol (SCP), derived from renewable resources—cardanol and polyethylene glycol—for application in waterborne polyurethane dispersions (WPUDs). Utilizing SCP as a chain extender, WPUDs were prepared through a typical acetone process with poly(butylene adipate) (PBA), isophorone diisocyanate (IPDI), and ethylene diamine (EDA) at a constant NCO/OH ratio of 1:1. This research focused on the effects of polyethylene glycol molecular weight and SCP dosage on the particle size, stability, and film-forming properties of the WPUD. Optimal dispersion stability and film-forming performance were achieved with a polyethylene glycol molecular weight of 1500 and a PBA to SCP molar ratio of 4:1, yielding a particle size of 0.326 ± 0.010 μm and excellent storage stability over six months. The resulting WPU coatings exhibited a tensile strength of 11.4 MPa, which increased to 16.8 MPa after UV irradiation owing to the formation of a semi-interpenetrating network via the photopolymerization of cardanol’s unsaturated side chains. UV cross-linking also enhanced water resistance, reducing the water absorption rate (WAR) from 18.68% to 4.21% and the water vapor transmission rate (WVTR) from 6.59 × 10−5 g·m⁻¹·Pa⁻¹·d⁻¹ to 2.26 × 10⁻⁵ g·m⁻¹·Pa⁻¹·d⁻¹, while also improving thermal stability. These findings demonstrate that SCP offers a sustainable and effective solution for developing high-performance WPU coatings.

Unveiling the Human Brain on a Chip: An Odyssey to Reconstitute Neuronal Ensembles and Explore Plausible Applications in Neuroscience.

The brain is an incredibly complex structure that consists of millions of neural networks. In developmental and cellular neuroscience, probing the highly complex dynamics of the brain remains a challenge. Furthermore, deciphering how several cues can influence neuronal growth and its interactions with different brain cell types (such as astrocytes and microglia) is also a formidable task. Traditional in vitro macroscopic cell culture techniques offer simple and straightforward methods. However, they often fall short of providing insights into the complex phenomena of neuronal network formation and the relevant microenvironments. To circumvent the drawbacks of conventional cell culture methods, recent advancements in the development of microfluidic device-based microplatforms have emerged as promising alternatives. Microfluidic devices enable precise spatiotemporal control over compartmentalized cell cultures. This feature facilitates researchers in reconstituting the intricacies of the neuronal cytoarchitecture within a regulated environment. Therefore, in this review, we focus primarily on modeling neuronal development in a microfluidic device and the various strategies that researchers have adopted to mimic neurogenesis on a chip. Additionally, we have presented an overview of the application of brain-on-chip models for the recapitulation of the blood-brain barrier and neurodegenerative diseases, followed by subsequent high-throughput drug screening. These lab-on-a-chip technologies have tremendous potential to mimic the brain on a chip, providing valuable insights into fundamental brain processes. The brain-on-chip models will also serve as innovative platforms for developing novel neurotherapeutics to address several neurological disorders.

Casein network formation at oil–water interfaces is reduced by [formula omitted]-casein and increased by Ca[formula omitted]

Mixtures of bovine caseins can serve as a benchmark for understanding the functionality of microbial-based recombinant caseins at oil–water interfaces. In this work we show that, in the presence of Ca2+, the individual casein fractions form viscoelastic networks at the oil–water interface with comparable stiffness. In the absence of Ca2+, αs2- and β-casein interfacial network formation was strongly inhibited over the full deformation regime. For αs1-casein, the network stiffness was increased in the absence of Ca2+ at small deformations (<15%), but at large deformations (>50%) it was completely disrupted, to a similar stiffness as αs2- and β-casein. The interfacial structure formed by κ-casein was largely unaffected by Ca2+ due to limited phosphorylation. We hypothesize that the differences between calcium-sensitive caseins lie in the conformation they assume at the interface. Both αs2- and β-casein adsorb in a train-tail conformation with a tail extending into the aqueous bulk phase, whereas αs1-casein adsorbs in a loop-train conformation, with a loop that extends less into the bulk phase. The tail-train configuration is hypothesized to increase the inter-molecular Ca2+ bridging thereby increasing the interfacial stiffness of αs2- and β-casein.Blending the casein fractions revealed a strong negative effect of β-casein on the interfacial modulus, which was more pronounced at a higher concentration. The presence of Ca2+ remained important for interfacial network formation of a casein blend. Without Ca2+, the interfacial network was less stiff, more viscous, and behaved like a 2d polymer solution.With this work we showed that casein interfacial network formation at oil–water interfaces is mediated by Ca2+ bridging. Blending the different casein fractions decreased the interfacial viscoelastic properties through the presence of β-casein. These results indicate that future work on recombinant caseins should focus on single genetic variants, since a blend of variants will likely decrease interfacial functionality.

Study on Low‐Cycle Fatigue Behavior and Life Prediction of Cr–Ni–Mo–V Gun Steel at Room Temperature and 600 °C

ABSTRACTIn this paper, the low‐cycle fatigue fracture behavior and life prediction of Cr–Ni–Mo–V gun steel at room temperature and 600 °C are studied. The results indicated that at room temperature and 600 °C, the Cr–Ni–Mo–V gun steel exhibited obvious monotonic softening and cyclic softening. This behavior could be attributed to the formation of dislocation networks, dislocation walls, dynamic recovery, and dynamic recrystallization. As the temperature increased, the failure mode gradually shifted from mixed transgranular and intergranular fractures to intergranular fractures possibly owing to the reduced grain boundary strength and easy oxidation of the grain boundary at high temperatures. In addition, the fatigue life prediction model considering the influence of temperature is established by using the energy dissipation quadratic function, offering a practical method to improve the fatigue performance evaluation of Cr–Ni–Mo–V gun steel at various temperature.