Collective Response Research Articles

Ca and Mg mixed effect on thermal conductivity in a borosilicate glass series

Abstract This study systematically investigates the effects of isovalent cation substitution (Mg2+ for Ca2+) on the thermal transport properties in a borosilicate glass series with the nominal molar composition 65.0SiO2·5.0B2O3·17.6K2O·(12.4 − x)CaO·xMgO. Through controlled compositional variation (substitution ratio R = [Mg]/([Ca] + [Mg]) from 0.0 to 1.0), we observe a significant linear enhancement in thermal conductivity (ĸ) with increasing R. Analysis within the phonon gas model framework reveals that the κ evolution primarily correlates with systematic changes in Debye sound velocity (νD), while both volumetric heat capacity (CV) and phonon mean free path (Ɩ) exhibit negligible variation across the series. The observed linear κ–R relationship emerges from the collective linear response of νD, CV, and Ɩ to compositional modification. Combined with the linear evolution in thermal behaviors, further structural characterization through Raman spectra and 29Si nuclear magnetic resonance (NMR) suggests that Mg2+ predominantly does not act as a network intermediate or former oxide, but as a network modifier in the present glass series. These atomistic structural modifications, manifested as enhanced network rigidity and optimized bond vibration characteristics, provide fundamental mechanistic explanations for the observed thermal transport behavior. This work establishes a quantitative composition–structure–property relationship in modified borosilicate glasses, demonstrating that isovalent cation substitution offers a predictable pathway for tailoring thermal performances.

Maximal response to a mechanical leader at critical group size in ant collectives

It is widely recognized that biological collectives operate near criticality to amplify their capability of collective response. The peak in susceptibility near criticality renders these groups highly responsive to external stimuli. While this phenomenon has been recognized and supported by evidence from theory, a direct experimental demonstration has been elusive. To bridge this gap, here we record the response of a group of Paratrechina longicornis ants to external stimuli as they join efforts to carry food to their nest. Using a robotic system that mimics a transient leader, we apply tactile ant-scale forces and measure the group’s response at sub, near, and supercritical regimes. Supported by theory and simulations, we provide direct experimental evidence to demonstrate that at critical group size, the collective response of the ants to an external force is maximally amplified.

Structural state governs the mechanism of shear-band propagation in metallic glasses

Shear bands (SBs) play a critical role in determining the mechanical behavior of metallic glasses (MGs). However, the rapid dynamics and highly localized nature of SB propagation present significant challenges for direct observation of their atomistic mechanisms using experimental techniques. In this study, we employ hybrid molecular dynamics/Monte Carlo simulations to investigate the atomic-scale mechanisms of SB propagation in Mg65Cu25Y10 MGs, prepared using cooling rates as slow as 104 K s-1-comparable to experimental casting conditions and significantly slower than the 1010 K s-1 rates previously employed in atomistic simulations. Our results reveal a qualitative shift in SB propagation mechanisms as the structural state evolves with decreasing cooling rates. In hyperquenched MGs, SB propagation occurs intermittently, characterized by a "stop-and-go" motion driven by sequential activation and coalescence of multiple shear transformation zones (STZs) separated by vortex-like fields. In contrast, slowly cooled MGs exhibit continuous and rapid SB propagation, mediated by localized shear softening and the formation of large vortex fields, indicative of a more collective structural response. This transition arises from significant differences in the number density and spatial distribution of activated STZs across different structural states. These findings provide insights into the microscopic dynamics of SB initiation and propagation in MGs, highlighting how the structural state can be strategically tuned to control SB behavior. This opens up different opportunities for optimizing the mechanical performance of MGs for targeted engineering applications.

Observation of chiral emission enabled by collective guided resonances.

A simple yet insightful question is whether it is possible to arrange optical resonances in such a way that their collective response differs from that of the individual constituents. Here, inspired by the collective oscillation of spatially localized modes and Fourier duality between real and momentum spaces, we demonstrate a chiral emission of collective guided modes by leveraging the omnidirectional hybridization of individual guided resonances within a photonic crystal slab. Specifically, we encircle a uniform photonic crystal with isotropic boundaries and hybridize discrete bulk guided resonances into a series of collective modes owing to the scatterings of the boundaries. This results in a chiral spiral vortex emission in real space. By using asymmetric pumping to lift the chiral symmetry, we then achieve stable single-mode lasing oscillation of the spiral collective mode and confirm the nature of vortex emission through polarization-resolved imaging and self-interference patterns, thus demonstrating a vivid example of collective oscillations in the momentum space.

Young people, Instagram, sexist violence and alcohol: Pre(inter)vention through Social Work

Introduction. The specialized literature has drawn attention to youth dynamics in online environments, highlighting new relational spaces where traditional offline youth leisure interactions have been transferred. Among these practices, two main ones stand out: the reproduction of gender-based violence in digital spaces, and the use of social networking sites linked to alcohol consumption as an emerging topic of research. Based on this theoretical development, the confluence of such violence and problematic consumption is beginning to emerge as a new field of study. This article presents part of the results of a project with young people from different Spanish localities, addressing the interrelation between these two issues, still under-researched. The objective is to analyse youth communication on social networking sites, such as Instagram, to understand how they relate to the use and abuse of alcohol and its role in violent behaviours. The ultimate goal is to propose intervention strategies against gender-based violence in digital environments where young people spend their leisure time, ones involving the constant use of social networking sites and, frequently, the consumption of alcohol or other drugs. Methodology. The study was conducted through 38 in-depth interviews and 13 focus groups, with a total of 118 participants from 12 Autonomous Communities. The sample selection focused on individuals aged 15 to 24, with active profiles on the social networking site Instagram and who consumed alcohol (from occasionally to intensively). Results. The testimonies analysed reveal three discursive repertoires that demonstrate the relationship between sexist violence and the projection of masculinity in digital spaces. Simultaneously, we identified a series of individual and collective response strategies to such behaviour, showing both the youth's agency and the versatility offered by social networking sites to address problems associated with their misuse. Discussion. The results highlight the multi-level violence faced by young women daily in the virtual sphere and their vulnerability to the aggressive behaviour of boys, consistent with previous research. These specific gender risks reveal the dual paradox of the “Net”, as it is neither delocalized nor reticulated. This opens up a space for social intervention from a preventive perspective, working with young people on the three axes: the consumption of alcohol and other drugs, social networking sites, and gender-based violence. Conclusions. Social Work provides theoretical and methodological tools to address the problem through multidisciplinary teams that approach media literacy and youth relational sociability from a gender perspective and with an intersectional focus.

Enhancing the resilience of short food supply chains: toward a relational understanding of the resilience process in the face of inflation

Short food supply chains (SFSCs) have proven their resilience during recent challenges, including the COVID-19 global pandemic. The recent rise in inflation in France has posed new challenges too. This study examines how short food supply chains in the South of France are responding to the challenges posed by inflation including rising production costs and a potentially shrinking consumer base. We propose integrating the resilience literature with the concept of embeddedness. Through this cross-fertilization, we conceptualize resilience as a dynamic process shaped by relationships and consisting of distinct stages: absorption, adaptation, and transformation. The study, based on 30 semi-structured interviews with horticultural farmers, reveals the existence of distinct phases in farmers’ responses to the situation. In the early stages, farmers collectively tackled the problem of rising costs by using shared resources and social networks. During the adaptation phase, pricing strategies were adjusted, facilitated by cooperative agreements between producers in different SFSCs. In the transformation phase, farmers shifted to direct sales to reduce their dependence on unreliable retail intermediaries. SFSCs not only adapted to economic shocks but also cultivated resilient strategies that strengthened community ties. Our research highlights the complex and multifaceted nature of relationships within SFSCs, which typically begin as primarily transactional and often evolve to include elements of friendship and mutual support. Such relationships facilitate flexible and collective responses to disruptions. In addition, the study identifies shortcomings in current resilience frameworks, particularly with regard to addressing systemic challenges and the role of public policy. Future research would benefit from exploring how institutional support and territorial embeddedness can further enhance the resilience of SFSCs in different socio-economic contexts.

Analisis Kasus Penistaan Agama dalam Perspektif Forum Umat Islam Sumatera Utara

This study discusses the response of the Forum of Islamic Community of North Sumatra Amal Ma’ruf Nahi Munkar (FUI-SU AMANAR) to the case of religious blasphemy committed by RS in Medan Sunggal. This study aims to analyze the form of religious blasphemy committed and the response given by FUI-SU AMANAR, as well as to seek solutions to the problem. The method used is qualitative descriptive with a phenomenological approach to religion. The results show that the RS case provoked emotional and collective responses from the community, including mass actions and demands for law enforcement officials to take action. FUI-SU AMANAR took concrete steps by conducting clarifications, internal investigations, and mediation with authorities. This research emphasizes that religious blasphemy in the digital era has wide social impacts that spread rapidly, thus requiring wise, firm, and peaceful responses from various parties, especially religious organizations. The study also provides understanding about the importance of Islamic organizations in maintaining social harmony and acting as a balancing force in the religious dynamics of society.

Is Digital Government Strengthening or Weakening Society?

Governments are facing technical, organizational, political, financial, etc. limitations on their capacity to tackle major policy problems like pandemics, climate change, migration, etc. that endanger societal well-being, security, and development. Overcoming such limitations requires a collective response, where different members of the society – individuals and institutions – are working with government and each other to address the problem. The aim of this paper is to examine the digital transformation of government and whether the outcome – digital government – makes society stronger or weaker, thus facilitating or undermining such collective response. To this end, we examine six qualities of social development – inclusion, equality, justice, collectivism, order and democracy – which presence or absence make societies stronger or weaker, and collect the evidence from scientific literature of digital government impacting such qualities, leading to inclusive vs. exclusive societies, equal vs unequal societies, just vs. unjust societies, etc. The result of this research is a landscape of different approaches, experiences, and designs, through which digital government contributes to the presence or absence of these qualities. This result has both research and policy implications.

Generation Mechanism of Collective Emotional Resonance: A Study on Group Emotions and Cultural Identity in Digital Exhibitions of Intangible Cultural Heritage Costumes

Digital technology transforms intangible cultural heritage (ICH) exhibition methods, fundamentally reshaping audiences' emotional experiences and cultural identity processes. Based on Stimulus-Organism-Response (S-O-R) framework, this study constructs a conceptual model encompassing performance characteristics (stimulus), collective emotional responses (organism), and behavioral intention (response), with cultural identity as moderating variable. Through cross-sectional survey of 468 exhibition visitors, hypotheses were tested using structural equation modeling, mediation and moderation analyses. Findings demonstrate that Presence, Embodied Interaction, and Historical Authenticity significantly influence Collective Emotional Arousal; Collective Emotional Arousal and Emotional Contagion promote Behavioral Intention; Cultural Identity moderates effects of Presence and Historical Authenticity. This research extends theoretical boundaries of emotion in virtual environments, providing guidance for transitioning from individual to collective experience design in human-computer interaction systems, cultural adaptability in cross-cultural interactions, and multi-dimensional digital performance frameworks.

IoT enabled human-machine systems for smart city infrastructure – present scenario and challenges

Purpose This study aims to look at how important the Internet of Things (IoT) is to creating smart cities. It emphasizes how IoT technologies maximize the use of resources, improve public services and raise the standard of living for citizens. Furthermore, it investigates how IoT may support sustainability while addressing important urban issues including energy use, transportation congestion and public safety. Design/methodology/approach This study explores the IoTs’ architecture, uses and difficulties in smart cities. The study highlights the use of data analytics techniques to enable the integration of connected devices with cutting-edge technology to address problems like scalability, security and data overload. Particularly in relation to IoT-enabled smart city infrastructure and services, the function of data analytics in converting unprocessed IoT data into useful insights is being explored. Findings The report emphasizes how IoT is essential to building smart cities because it promotes efficiency, adaptability and urban environments that are focused on the needs of their citizens. Real-time interaction, optimizing resources and urban oversight are all enhanced by IoT-enabled smart city systems. Real-time data gathering, analysis and visualization are made possible by Web platforms, portals and applications, which are essential for integrating IoT data for smart city management. Key urban indicators like traffic flow, quality of air and energy usage can be tracked by municipal authorities using interactive interfaces offered by Web-based IoT dashboards. Urban management is improved by real-time online monitoring systems, which track smart city infrastructure continually and optimize waste collection, traffic lights and public safety responses. Furthermore, large-scale data processing, storage and predictive analytics are made possible by cloud-based Web services like Microsoft Azure IoT and AWS IoT, which guarantee effective resource allocation and decision-making. Smart cities may develop data-driven, adaptable urban settings, increase citizen services and increase sustainability by using these technologies. Originality/value The study thoroughly examines how IoT affects smart cities, highlighting how it can address urban issues while promoting sustainability. IoT and modern data analytics together reveal ideas that improve cities’ responsiveness to citizen demands, efficiency and flexibility. This study contributes by providing information on cutting-edge strategies that aid in the creation of robust and citizen-focused smart urban infrastructures.

Does nematic order allow groups of elongated cells to sense electric fields better?

Collective response to external directional cues like electric fields helps guide tissue development, regeneration, and wound healing. In this study we focus on the impact of anisotropy in cell shape and local cell alignment on the collective response to electric fields. We model elongated cells that have a different accuracy sensing the field depending on their orientation with respect to the field. With this framework, we assume cells are better sensors if they can align their long axes perpendicular to the field. Elongated cells often line up with their long axes in the same direction - "nematic order" - does a nematic cell-cell interaction allow groups of cells to share information about their orientation to sense fields more accurately? We use simulations of a simple model to show that if cells orient themselves perpendicular to their average velocity, alignment of a cell's long axis to its nearest neighbors' orientation can in some circumstances enhance the directional response to electric fields. We also show that cell-cell adhesion modulates the accuracy of cells in the group.

‘A trusted person is cursed’. Trust as an accountability mechanism in the Somali collective response to crises

A wide range of actors respond to humanitarian crises, including those present in or socially embedded in the local context. How are local responders held accountable by those who provide them with funds to support collective responses to crisis, and by those they provide assistance to? We answer this question through empirical research on collective crisis responses during droughts in Somaliland. Somaliland is a self-declared republic in the northern region of Somalia, seeking international recognition and functioning with its own government and institutions since 1991. In Somaliland, social security is rarely provided by the state, but is rather supplied within kinship- and locality-based networks, which also play a central role in times of crisis. We argue that elaborate accountability systems exist, embedded in social practice. These systems are built on long-term relationships and are more holistic in scope than narrowly defined technical-financial understandings of accountability common in international humanitarianism. Drawing on literature on trust and our empirical research, we argue that locally-embedded humanitarianism needs to be understood from a relational ethical perspective. In Somali collective crisis response, accountability practices are upheld collectively. They are built and maintained through reciprocity and individuals fulfilling expectations, thus further cementing existing social relations. Informal accountability measures to sanction an abuse of trust in this context serve to strengthen the social support system rather than punish individual wrongdoings. Wrongdoers are thought to receive their punishment through being cursed, face the wrath of God, and societal condemnation.

Investigating Descriptive Norms’ Influence on Online Donation Intention via the Perspective of Norm-Regulated Responsibility: A Pre-Registered Study

Previous studies frequently demonstrate that descriptive norm messages positively influence behavior. However, research indicates that in prosocial contexts, these messages may reduce individuals’ perceived personal responsibility and, in turn, hamper prosocial behavior intentions. This study replicates these findings in the context of online donations and extends the model by incorporating personal and collective response efficacy as mediators. Through a pre-registered experiment, the study reveals a significant negative effect of descriptive norm messages on perceived personal responsibility among individuals without prior user experience.

Networked Justice: The Actions and Effects of Cancel Culture on YouTube

This article explores Cancel Culture as a valuable and limited collective response to the violation of social values. It uses two examples of Cancel Culture on YouTube—that of James Charles (2019) and Colleen Ballinger (2023)—to examine how networked publics play the important role of serving networked justice.

The Role of Multilateralism in Addressing Global Humanitarian Crises: A Case Study of International Interventions in Gaza and Ukraine

This study investigates the role of multilateralism in addressing global humanitarian crises through a qualitative, literature-based approach, focusing specifically on international interventions in Gaza and Ukraine. Drawing on a systematic review of ten scholarly articles and institutional reports, this research explores how multilateral frameworks—primarily under the auspices of the United Nations and related bodies—function in contexts marked by political complexity, ethical dilemmas, and operational constraints. The findings highlight that while multilateralism remains a normative and structural foundation for collective humanitarian responses, its effectiveness is often compromised by geopolitical interests, funding disparities, fragmented coordination, and selective implementation of international norms. The cases of Gaza and Ukraine illustrate both the potential and limitations of multilateral engagement: in Gaza, humanitarian access is heavily politicized and frequently obstructed, whereas in Ukraine, coordinated aid delivery faces challenges related to conflict dynamics and regional polarization. The discussion draws on liberal institutionalist theory and the concept of “organized hypocrisy” in international relations to critically assess the gap between normative commitments and practical outcomes. This study concludes that although multilateralism continues to be essential for humanitarian legitimacy and coordination, its future effectiveness will depend on institutional reform, greater regional integration, and enhanced local legitimacy. The paper recommends further research into regional multilateral responses and ground-level perceptions of humanitarian actors to better understand the evolving landscape of global crisis governance.

Resolving Localized Plasmonic and Photonic Modes of Gold Nanosponges via Cathodoluminescence Spectroscopy

Abstract Localizing optical fields at deep sub‐wavelength scales has applications in ultra‐strong light‐matter interactions and in efficient coupling to quantum emitters. Surface plasmon polaritons can be confined within and on the surfaces of nanostructures on spatial scales of only a few nanometers. However, they generally suffer from significant dissipation. Porous gold nanosponges and percolated thin films demonstrate an interestingly highly‐localized plasmonic feature with an enhancement factor and quality factor beyond what is achievable with localized plasmons in nanostructures. Here, the characteristics of plasmon resonances in porous gold nanoparticles are explored using cathodoluminescence spectroscopy. It is demonstrated that visible light can be localized inside the nanosponges at spatial scales as small as 20 nm, forming dipole‐like resonances. Moreover, it is shown that at specific wavelengths the entire structure supports a collective resonance, with the emitted light exhibiting polarization that represents an average over all possible dipolar emission directions. The analysis demonstrates the potential of gold nanosponges for exploring the intricate physics of localized resonances and their collective responses, and it paves the way toward their applications in controlling emissions from quantum emitters.

New venture team persistence: a dynamic model of how resilient teams transform collective adaptive responses under adversity

New venture team persistence: a dynamic model of how resilient teams transform collective adaptive responses under adversity

Balanced state of networks of winner-take-all units.

Irregularly timed action potentials, or spikes, are pervasively observed in the brain activity of awake mammals. However, the role of this temporal irregularity in neural computation is still not well understood. In canonical network models irregular spiking emerges via balanced, fluctuating input currents, leading to collective responses that track inputs linearly. How networks characterized by irregular spiking could support flexible nonlinear dynamics needed for general-purpose computation remains under ongoing debate. Here we characterize the dynamics of networks whose elementary unit is not a single neuron but a small group of neurons, with distinct tunings, that compete at each timestep via a winner-take-all (WTA) interaction. While WTA has long been proposed as an elementary functional motif in the brain and represents a powerful computational primitive, how large networks of such units behave has received less investigation. We show that these networks, like classic excitatory-inhibitory balanced networks, exhibit a chaotic fluctuation-driven regime characterized by sustained irregular activity resembling realistic cortical spiking, which we interpret as a multidimensional balance spread over several competing neural populations with different tunings. We develop a mean-field theory for the network, which shows how irregular spiking sustained by time-varying input fluctuations can support flexible nonlinear collective dynamics. Using the theory we predict and verify network regimes in which input fluctuations alone yield multistability, stable sequence generation, or complex heterogeneous firing rate dynamics-three core dynamical primitives thought to underlie memory-dependent neural computation-via consistent Poisson-like spiking produced through chaos. Thus, networks of WTA units support a chaotic fluctuation-driven regime characterized by irregular spiking that can power complex nonlinear collective dynamics. This represents a new model of brain activity capable of simultaneously reproducing realistic spike trains and diverse nonlinear firing rate patterns well posed for flexible computation, and which can be trained or fit to data.

Defending Parliament Responses of Mainstream Parties to Parliamentary Erosion

Historically, extremist parties have engaged in a process of parliamentary disruption, violating the rules of interaction and slowing down the lawmaking process. How can democratic parties respond and counter parliamentary erosion? I propose a typology of the policies of parliamentary defense that includes targeting individual politicians and collective responses that change parliamentary or electoral rules. I explore the demand of political parties for different policies of parliamentary defense and the conditions under which legislative majorities in support of such policies come about. Empirically, the article examines the responses of mainstream democratic parties to parliamentary disruption in Weimar Germany (1918–1933) and Third Republic France (1919–1940).

Self-reorganization and Information Transfer in Massive Schools of Fish

The remarkable cohesion and coordination observed in moving animal groups and their collective responsiveness to threats are thought to be mediated by scale-free correlations, where changes in the behavior of one animal influence others in the group, regardless of the distance between them. But are these features independent of group size? Here, we investigate group cohesiveness and collective responsiveness in computational models of massive schools of fish of up to 50,000 individuals. We show that as the number of swimmers increases, flow interactions destabilize the school, creating clusters that constantly fragment, disperse, and regroup, similar to their biological counterparts. We calculate the spatial correlation and speed of information propagation in these dynamic clusters. Spatial correlations in cohesive and polarized clusters are indeed scale free, much like in natural animal groups, but fragmentation events are preceded by a decrease in correlation length, thus diminishing the group’s collective responsiveness, leaving it more vulnerable to predation events. Importantly, in groups undergoing collective turns, the information about the change in direction propagates linearly in time among group members, thanks to the non-reciprocal nature of the visual interactions between individuals. Merging speeds up the transfer of information within each cluster by several fold, while fragmentation slows it down. Our findings suggest that flow interactions may have played an important role in group size regulation, behavioral adaptations, and dispersion in living animal groups.