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The moisture with salt ions adsorbed on the mineral soil surface is crucial to the cohesion process when the media is exposed to marine or coastal environments. However, the impact of salinity on the cohesion of soils is not well studied at the nanoscale. In this study, the salinity effect was investigated by studying the wettability and capillary force of NaCl solutions on quartz substrates via a molecular dynamics-based approach. Besides, a new visualization method was proposed to measure the contact angle of liquid droplets from the aspect of nanoscale. The results indicated that salt ions can weaken the wettability of the liquid on the quartz surface and inhibit the capillary force. Compared with water, the liquid with a 10% NaCl solution can achieve a capillary force reduction of around 70%, resulting in a detrimental effect on the cohesion of soils. Overall, this study enhanced the understanding of the nanoscale salinity effect on the cohesion process and provided insights into the modification of the mechanical properties of soils from the aspect of nanoscale. [ABSTRACT FROM AUTHOR]

Much of the resistance and, at times, outright condemnation of including transgender individuals in sports continue to draw upon "scientific" arguments, despite the acknowledged importance of sociocultural and (geo)political factors, resulting in a constructed "either science or human rights" landscape. In this article, I analyze historical scientifically driven International Olympic Committee documents and policies from the Olympic Studies Center to examine if and how sport organizations, such as the International Olympic Committee, have historically balanced these seemingly partitioned considerations in previous regulatory documents, especially those relating to sex, gender, fairness, and protection. Using Sheila Jasanoff's co-production, I find that, while knowledge informing policies sometimes circulates biologized gender stereotypes, sociocultural and scientific goals have, can, and should exist in cohesion rather than in contradiction. [ABSTRACT FROM AUTHOR]

The massive amount of wasted heat energy from industry has pushed the development of thermoelectric (TE) materials that directly convert heat into electricity to a new level of concern. Recently, multicomponent alloys such as GeTe-based and PbSe-based high-entropy (HE) chalcogenides have attracted a great deal of attention due to their potential application as TE materials. The nature of the interatomic bonding, lattice distortion (LD), and the electronic structure in this class of materials is not fully understood. Herein, we report a comprehensive computational investigation of nine GeTe-based HE alloys with eight metallic elements (Ag, Pb, Sb, Bi, Cu, Cd, Mn, and Sn) with large supercells of 1080 atoms each; seven PbSe-based HE solid solutions: Pb0.99−ySb0.012SnySe1−2xTexSx (x = 0.1, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, with y = 0) with supercells of 1000 atoms each; and five Pb0.99−ySb0.012SnySe1−2xTexSx (y = 0.05, 0.1, 0.15, 0.2, 0.25 with x = 0.25) solid solutions with supercells of 1000 atoms each. All these HE models are theoretically investigated for the first time. The electronic structure, interatomic bonding, charge transfer, and lattice distortion (LD) are investigated by first-principles calculations based on density functional theory. Multicomponent HE alloys can cause a significant LD, which affects their mechanical, thermal, and TE properties. The calculations for the GeTe-based HE chalcogenides showed that they are semiconductors with a narrow bandgap, except for m8, which has a semi-metallic characteristic, and this makes them good candidates for TE applications. For most of these models, the Fermi level shifts upward and locates deeply in the conduction bands, resulting in the enhancement of the electrical conductivity (σ). The bonding properties showed that most bonds in m5 are more dispersed, indicating highest LD and lower lattice thermal conductivity. For PbSe-based HE solid solutions, the LD calculations showed that the models Pb0.99Sb0.012Se0.5Te0.25S0.25 and Pb0.89Sb0.012Sn0.1Se0.5Te0.25S0.25 have the higher LD, and thus a lower lattice thermal conductivity. Such investigations are in high demand since it enables us to design new HE chalcogenides for TE applications. We use the novel concept of total bond order density as a single quantum mechanical metric to characterize the internal cohesion of these HE alloys and correlate with calculated properties, especially the mechanical properties. This work provides a solid database for HE chalcogenides and a road map for many potential applications. Moreover, the computational procedure we developed can be used to design new HE chalcogenides for specific TE applications. [ABSTRACT FROM AUTHOR]

In the current study, the structural and external validity of data derived from two shorter versions of the Multidimensional Assessment of Teamwork in Sport (MATS) were examined using multilevel analyses. Evidence of model–data fit was shown for both a 5-factor model comprising 19 items (with subscales assessing teamwork preparation, execution, evaluation, adjustments, and management of team maintenance) and a single-factor model comprising five items (providing a global estimate of teamwork). In general, data from both versions were positively and significantly correlated with (and distinct from) athletes' perceptions of team cohesion, collective efficacy, performance satisfaction, enjoyment in their sport, and commitment to their team and their coaches' transformational leadership. The measures appear well suited to detect between-teams differences, as evidenced by intraclass correlation coefficients and acceptable reliability estimates of team-level scores. In summary, the 19-item Multidimensional Assessment of Teamwork in Sport-Short and five-item Multidimensional Assessment of Teamwork in Sport-Global provide conceptually and psychometrically sound questionnaires to briefly measure teamwork in sport. [ABSTRACT FROM AUTHOR]

Distance education is becoming a global phenomenon affecting student teamwork, especially since the outbreak of the COVID-19 pandemic. Nonetheless, research in management education on changes in team cohesion in student teams remains limited, and even less is known in the context of dynamic forms of modern virtual team collaboration. We address this gap by exploring how dynamic boundaries affect team cohesion via a study conducted across two editions (spring 2018 and spring 2019) of a cross-university course. Results from the qualitative triangulated data collected from a multiple holistic case study composed of 11 virtual student teams (n = 65 participants) suggest that in the virtual student teams, dynamic boundaries (such as dispersion, sub team formation, boundary spanning, multi teaming, and moving on and off the team) diminish team cohesion in favor of "participant alignment" and have differential relationships with this novel concept. Our results contribute to the literature on management education and team dynamics and can be applied in academic and management practice by shifting the focus away from team cohesion and toward participant alignment as a new individual-level, multidimensional concept. This has the potential to become an important aspect of successful virtual teams operating under modern dynamic conditions. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) adhesive derived from lignin-based polyol can be used as a substitute for urea–formaldehyde (UF) adhesive for plywood because it can be used for exterior application, it is more environmentally friendly, and does not produce formaldehyde emissions. This research work aimed to investigate and evaluate the adhesive performance of lignin-based PU adhesive for bonding plywood, synthesized by mixing methylene diphenyl diisocyanate (MDI), polyol, polyvinyl alcohol (PVOH), and lignin, then applied to the rubberwood (Hevea brasiliensis) veneers and hot-pressed at a temperature of 120 °C and a pressure of 2.5 MPa for 4 min. The lignin yield obtained was 36.17%, moisture content 5.07 ± 0.71%, ash content 0.31 ± 0.19%, and lignin purity 95.32 ± 0.61%. The increased addition level of PVOH/lignin resulted in decreased solids content of the adhesive, while viscosity, cohesion, torque, storage modulus, loss modulus, and tan delta increased. Based on the Fourier-transform infrared spectroscopy (FTIR) analysis results, urethane bonds were identified in both the adhesive and plywood. Lignin-based PU adhesive formulas with 10%, 20%, and 30% PVOH/lignin fulfilled the minimum requirements for delamination, tensile strength, and wood failure, as specified by the Japanese Agricultural Standard (JAS) No. 233:2003. Markedly, plywood bonded lignin-based PU adhesive with 30% PVOH/lignin met the standards of JAS No. 233:2003 for exterior grade plywood. [ABSTRACT FROM AUTHOR]

This study explores the impact of sociocultural theory-based instruction on enhancing L2 learners' writing skills including grammatical accuracy, coherence, cohesion, task response, and lexical resources for the IELTS. To this end, a cohort of 40 participants, spanning intermediate and advanced proficiency levels, was divided into experimental and control groups, each comprising 20 students. The research utilized the Oxford Placement Test to ensure a balanced distribution. Throughout the instructional period, learners actively participated in collaborative group activities and benefited from scaffolding techniques. The analysis of outcomes revealed the effectiveness of sociocultural strategies, leading to significant progress across different proficiency levels. While intermediate participants demonstrated marked improvements in task response, advanced learners exhibited heightened levels of coherence and cohesion in their writing. The findings indicate the paramount importance of employing scaffolding and collaborative methodologies to foster writing proficiency, particularly in the context of preparing for the IELTS. This research sheds light on the potential of sociocultural theory-based instruction to positively influence second language learners' writing abilities. [ABSTRACT FROM AUTHOR]

Recent times have shown that external conditions and climatic developments require more intensive consideration of the resilience of our infrastructures. This article presents the methodology and empirical results of a German spatial planning pilot project that systematically analysed the strategic options for maintaining the functionality of Services of General Interest (SGI) and Critical Infrastructures (CI) covering all of Germany’s federal states. Added value is created through a better understanding of the various infrastructures and their specific criticality and by answering how the infrastructures can be made more resilient and thus contribute to equal living conditions and territorial cohesion. The article also emphasises the connection between spatial resilience approaches and European cohesion and climate policy and makes recommendations for adaptation in European structural and funding policy. The authors recommend a systematic territorial consideration of SGI and CI to prevent negative effects on balanced and stable spatial development. To achieve this goal, interdependencies between infrastructures and cascading effects should be considered in the future. Infrastructures are usually bundled in central places. Therefore, the article also provides conceptual and practice-orientated proposals for planning strategies on which central places can be made more resilient. [ABSTRACT FROM AUTHOR]

When a shield tunnel is excavated in water-rich strata with soft upper and hard lower layers, the failure mode of the tunnel face may shift from an overall failure mode to a partial failure mode. To address this issue, three-dimensional discrete failure mechanisms for both partial and overall failure modes are established on the basis of the upper bound theorem and spatial discretization techniques. The influence of pore water pressure is also considered, leading to the development of a method for calculating the critical support force of tunnel faces in such strata, while taking into account both failure modes and the effects of groundwater. Through parameter analysis, factors such as the tunnel diameter, proportion of soft soil, stratum cohesion, and pore water pressure coefficient significantly influence the tunnel face failure mode. A comprehensive critical support force, which takes both partial and overall failure modes into account, is proposed. The parameter analysis reveals that this comprehensive critical support force exhibits complex variations under the influence of multiple parameters. At the same time, a method is proposed to determine the upper and lower bounds of the ultimate support force, based on the calculation results under no seepage and free seepage conditions at the excavation face. The entire method provides a valuable reference for the stability analysis of tunnel faces in water-rich strata with soft upper and hard lower layers. [ABSTRACT FROM AUTHOR]

The distribution range of soil-rock mixtures (S-RM) in fault zones is wide, with significant differences in mechanical properties, making them the main sites for rock instability and support structure failure in mines. This paper takes the Sanshan Island fault zone as the engineering background, and uses a self-designed small-scale test device to conduct triaxial compression tests to study the strength and deformation failure laws of S-RMs with different rock block proportions (20%, 40%, 60%, and 80%). Combined with numerical simulation test results, the spatial transport laws and microscopic deformation failure characteristics of particles with different particle sizes in the S-RM are revealed. The main conclusions drawn are as follows: (1) For S-RMs with rock block proportions (RBP) of 20%, 40%, and 60%, there is a linear positive correlation between confining pressure and peak strength. When the RBP increases to 80%, there is a non-linear positive correlation between the confining pressure and peak strength of the S-RM sample. Under the same increase in confining pressure, the increase in peak strength of the sample decreases. The influence of confining pressure on the strength and deformation characteristics of S-RMs with high RBP is reduced. (2) During the process of increasing the RBP from 20 to 60%, there is a linear positive correlation between the RBP and peak strength of the S-RM sample. When the RBP increases to 80%, the peak strength of the sample experiences a sudden increase, with an increase of nearly 80 kPa in peak strength. When the RBP is high, the S-RM sample exhibits the mechanical properties of block rocks. (3) The cohesion and internal friction angle of the S-RM sample are positively correlated with the RBP. During the process of increasing the RBP from 20 to 80%, the cohesion increases from 83.12 kPa to 119.38 kPa, and the friction angle increases from 6° to 11°. (4) When the RBP is low (20% and 40%), as the experiment progresses, a significant conjugate shear deformation zone will form within the S-RM sample, and block rock particles will migrate towards this area and undergo shear slip failure between particles. When the RBP is high (60% and 80%), splitting failure mainly occurs at the bonding surface between block rock particles and soil particles inside the sample, and the contact force between particles is relatively large. The relevant research results have important social and economic value for revealing the fracture failure laws of rock masses in fault zones and ensuring the safe development of human engineering activities. [ABSTRACT FROM AUTHOR]

In this work, the particle flow of wet coal particles in the segmented cross-screening process was simulated by DEM (discrete element method) with linear cohesion model. The screening mechanism of segmented cross-screening was investigated, and the simulation results were verified by experimental-scale cross-screen. Based on the Box-Behnken design (BBD) method, the effect of screen inclination (θ1, θ2, θ3) on screening performance was investigated, and the optimized combination of screen inclination was used to further improve the screening efficiency. The results show that the segmented cross-screen structure significantly affects the screening effect, with the most pronounced impact observed in the screen inclination θ3. The best combination of surface inclination is θ1 = 10.39°, θ2 = 17.64° and θ3 = 23.97°, at which time the screening efficiency can reach 90.09%. This work contributes to the understanding of the cross-screening mechanism and provides the necessary reference for the optimal design of segmented cross-screens. [ABSTRACT FROM AUTHOR]

Growing affective polarization, or animosity between competing ideological groups, threatens to tear apart democratic societies worldwide. In nations that are facing external conflicts, the threat arising from these conflicts may boost internal cohesion and potentially reduce the internal threat of fragmentation. However, in the current study, we analyze survey datasets from two societies embedded in intractable conflicts, South Korea (N = 897) and Israel (N = 504), and demonstrate that gaps in the perception of the external threat between competing ideological groups are related to higher levels of affective polarization within these societies. We also find support for a mechanism that explains this trend: an internal threat from the ideological outgroup. We discuss the implications of our findings for the study of conflicts' impact on intragroup processes, specifically affective polarization, and for the understanding of how such processes might perpetuate the conflict itself. [ABSTRACT FROM AUTHOR]

This paper contributes to the literature on the territorial dimension of EU Cohesion Policy and spatial planning in EU Member States. It offers a perspective on these debates by focusing on the case study of the Czech Republic which exemplifies the group of countries being the main beneficiaries of Cohesion Policy. Building on interviews, document analyses and interactive workshops, the barriers and potentials for cross-fertilisation between Cohesion Policy and spatial planning are identified. Upon this background, concrete policies are recommended. Therefore, the paper goes a step further by explaining why the problem occurs and what can be done about it. [ABSTRACT FROM AUTHOR]

Cohesive granular materials are found in many natural and industrial environments, but experimental platforms for exploring the innate mechanical properties of these materials are often limited by the difficulty of adjusting cohesion strength. Granular particles levitated in an acoustic cavity form a model system to address this. Such particles self-assemble into free-floating, quasi-two-dimensional raft structures which are held together by acoustic scattering forces; the strength of this attraction can be changed simply by modifying the sound field. We investigate the mechanical properties of acoustically bound granular rafts using substrate-free micro-scale shear tests. We first demonstrate deformation of rafts of spheres and the dependence of this deformation on acoustic pressure. We then apply these methods to rafts composed of anisometric sand grains and smaller spheres, in which the smaller spheres have a thin layer of air separating them from other grain surfaces. These spheres act as soft, effectively frictionless particles that populate the interstices between the larger grains, which enables us to investigate the effect of lubricating the mixture in the presence of large-grain cohesion. [ABSTRACT FROM AUTHOR]

The purpose of this study is to solve the problem of the harmless treatment of dredged silt and soil extraction during road construction in lake areas. The silt in the project area is used as the research material to evaluate its engineering applicability as an improved filling material for the roadbed of the lake's surrounding road. Through indoor pretreatment and a series of mechanical performance tests, including compaction tests, unconfined compressive strength tests (UCS), bearing ratio tests (CBR), triaxial compression tests (CU consolidated undrained), and consolidation tests, we obtained key mechanical parameters of modified sludge soil, such as maximum dry density, optimal moisture content, unconfined compressive strength, bearing ratio, shear strength, and compression characteristics. The research results show that with the increase in modifier dosage, the optimal moisture content of modified sludge soil increases, the maximum dry density decreases, and its compressive strength and shear strength significantly improve. The CBR value also meets the technical requirements of each layer of the roadbed. Specifically, after 7 days of curing, the compaction degree of 10% modified sludge soil can exceed 96%, the unconfined compressive strength reaches 0.819 MPa, the CBR value reaches 17.5, the cohesion measured by triaxial tests is 78 kPa, the internal friction angle is 27°, and it exhibits low compressibility. These findings provide new solutions for environmentally friendly treatment, resource utilization, and road engineering in river and lake sediments. [ABSTRACT FROM AUTHOR]