Search Results (1,660)

Phase transformations induced by short optical pulses are mainstream in studies on the dynamics of cooperative electronic states. We present a semiphenomenological modeling of spatiotemporal effects expected when optical excitons are intricate with the order parameter such as in, e.g., organic compounds with neutral-ionic ferroelectric phase transitions. A conceptual complication appears here, where both the excitation and the ground state ordering are built from the intermolecular electronic transfer. To describe both thermodynamic and dynamic effects on the same root, we adopt, for the phase transition, a view of the excitonic insulator—a hypothetical phase of a semiconductor that appears if the exciton energy becomes negative. After the initial pumping pulse, a quasi-condensate of excitons can appear as a macroscopic quantum state that then evolves, while interacting with other degrees of freedom which are prone to an instability. The self-trapping of excitons enhances their density, which can locally surpass a critical value to trigger the phase transformation. The system is stratified in domains that evolve through dynamical phase transitions and may persist even after the initiating excitons have recombined. Full article

Background: Cervical cancer remains a significant health concern worldwide and the primary cause of cancerous cervical lesions is the infection with high-risk human papillomavirus (HR-HPV). However, emerging evidence suggests that HR-HPV infection alone is insufficient for cancer development, and other co-factors may contribute to cervical carcinogenesis. Human cytomegalovirus (HCMV), a common herpesvirus frequently detected in cervical cancer samples, has demonstrated oncogenic potential. Objectives: This review aims to explore the molecular interactions between HR-HPV and HCMV in promoting cervical cancer progression. Methods. A comprehensive search was conducted in PubMed and Google Scholar, focusing on articles examining the role of HCMV in cervical tissues and/or cells, selected based on relevance and significance. Results: The reviewed literature indicates that HCMV and HR-HPV share several oncogenic mechanisms that could drive cervical cell transformation. Conclusions. Both viruses may synergistically promote cervical epithelial transformation and tumor progression in multiple ways. HR-HPV may facilitate HCMV entry by increasing host cell receptors essential for viral attachment. Additionally, HR-HPV and HCMV may cooperatively disrupt cellular processes, enhancing carcinogenesis. Both viruses may also modulate the local immune environment, enabling immune evasion and lesion persistence. However, further in vitro and in vivo studies are required to validate these hypotheses. Full article

To support the ambitious bioeconomy vision outlined in Ireland’s Bioeconomy Action Plan, there is an urgent need to bring together the necessary stakeholders required to implement this vision. Farmers and other primary producers who oversee the production of sustainable biomass constitute one of the most important categories of stakeholders in the bio-based value chain. To ensure scalable, long-lasting bioeconomy collaboration, it is essential that farmers are involved in developing this bioeconomy vision. The current study provides a mixed-methods approach to co-design a green biorefinery vision with Irish farmers and other key value-chain actors. The selected value chain targeting a medium-scale grass silage biorefinery focused on the production of eco-insulation materials, with protein and biogas co-products for local markets. This was then assessed economically using an economic model, which provided a payback period of five years. To identify suitable sites for deployment of the green biorefinery in rural areas, geographical information systems (GIS) analysis was undertaken, considering various environmental, socio-economic and infrastructural variables, which identified 26 potential sites for deployment of the green biorefinery model in Ireland. This study found that early engagement with and inclusion of the farmers in a co-designed process of innovation and alternative revenue streams for them is essential. While a preferred cooperative-based business model for a grass silage biorefinery was identified in consultation with the multiple stakeholders, further research on its long-term commercial sustainability is proposed as future research. Full article

This study assessed the drought susceptibility in Golestan Province, Northeastern Iran, using land use change modeling and climate projections from the CMIP6 framework, under three Shared Socioeconomic Pathways (SSP1-2.6, SSP2-4.5, and SSP5-8.5) for 2030–2050. The development of current (2022) and future drought susceptibility maps was based on agrometeorological sample points and 14 environmental factors—such as land use, precipitation, mean temperature, soil moisture, and remote sensing-driven vegetation indices—used as inputs into a machine learning model, maximum entropy. The model showed a very robust predictive capacity, with AUCs for the training and test data of 0.929 and 0.910, thus certifying the model’s reliability. The current analysis identified major hotspots in Gomishan and Aqqala, where 66.12% and 36.12% of their areas, respectively, exhibited “very high” susceptibility. Projections under the SSP scenarios, particularly SSP5-8.5, indicate that the risk of drought will be the most severe in Maraveh Tappeh, where 72.09% of the area exhibits a “very high” risk. The results revealed that Golestan Province is at a crossroads. Rising temperatures, exceeding 35 °C in summer, combined with declining rainfall, intensify agricultural and hydrological droughts. These aggravated risks are compounded with land use transitions from rangelands to bare land, mostly in Aqqala and Gomishan, besides urban expansion in Bandar-e Torkman and Bandar Gaz, all of which face less groundwater recharge and increased surface runoff. Golestan’s drought vulnerability has both local and regional impacts, with its increased susceptibility affecting neighboring communities and ecosystems. Trade, migration, and ecological stresses linked to declining water resources may emerge as critical challenges, requiring regional collaboration for mitigation. Targeted interventions prioritizing sustainable land use practices, regional cooperation, and collaborative strategies are essential to address and mitigate these cascading risks and safeguard vulnerable communities. Full article

The integration of the Industrial Internet of Things (IIoT) and federated learning (FL) can be a promising approach to achieving secure and collaborative AI-driven Industry 4.0 and beyond. FL enables the collaborative training of a global model under the supervision of a central server while ensuring that data remain localized to ensure data privacy. Subsequently, the locally trained models can be aggregated to enhance the global model training process. Nevertheless, the merging of these local models can significantly impact the efficacy of global training due to the diversity of each industry’s data. In order to enhance robustness, we propose a Shapley value-based adaptive weighting mechanism that trains the global model as a sequence of cooperative games. The client weights are adjusted based on their Shapley contributions as well as the size and variability of their local datasets in order to improve the model performance. Furthermore, we propose a quantization strategy to mitigate the computational expense of Shapley value computation. Our experiments demonstrate that our method achieves the highest accuracy compared to existing methods due to the efficient assignment of weights. Additionally, our method achieves nearly the same accuracy with significantly lower computational cost by reducing the computation overhead of Shapley value computation in each round of training. Full article

The increasing volume of traffic has led to severe challenges, including traffic congestion, heightened energy consumption, increased air pollution, and prolonged travel times. Addressing these issues requires innovative approaches for optimizing road network utilization. While Deep Reinforcement Learning (DRL)-based methods have shown remarkable effectiveness in dynamic scenarios like traffic management, their primary focus has been on single-agent setups, limiting their applicability to real-world multi-agent systems. Managing agents and fostering collaboration in a multi-agent reinforcement learning scenario remains a challenging task. This paper introduces a cooperative multi-agent federated reinforcement learning algorithm named FLDQN to address the challenge of agent cooperation by solving travel time minimization challenges in dynamic multi-agent reinforcement learning (MARL) scenarios. FLDQN leverages federated learning to facilitate collaboration and knowledge sharing among intelligent agents, optimizing vehicle routing and reducing congestion in dynamic traffic environments. Using the SUMO simulator, multiple agents equipped with deep Q-learning models interact with their local environments, share model updates via a federated server, and collectively enhance their policies using unique local observations while benefiting from the collective experiences of other agents. Experimental evaluations demonstrate that FLDQN achieves a significant average reduction of over 34.6% in travel time compared to non-cooperative methods while simultaneously lowering the computational overhead through distributed learning. FLDQN underscores the vital impact of agent cooperation and provides an innovative solution for enabling agent cooperation in a multi-agent environment. Full article

Foreign capital has dominated over half of the public–private partnership (PPP) projects in developing countries over the past three decades. As such, attracting and regulating foreign participation in water PPP projects presents a critical challenge for both practitioners and scholars. Using a dataset of 2024 water PPP projects from 1994 to 2021, this study investigates foreign participation and its fall in China’s water PPP projects. Our findings highlight three key points: First, the proportion of projects undertaken by foreign capital decreased from 100% to less than 0.5%, with Chinese domestic capital taking its place. Second, resource dependence on foreign capital and the local government’s need for control lead to four types of foreign participation: financing water plants under user-pays, financing and operating water utilities under government-pays, participating with mainly an O&M role, and nearly no participation. Third, a better balance between efficiency gains and control needs via cooperation with domestic capital by local governments had driven the decline in foreign participation. This study makes two key contributions: (1) it is one of the pioneer studies on systematically tracing the evolution of foreign participation in PPP projects, and (2) it explains the fall of foreign participation from a local government perspective, complementing market-based explanations. Full article

The determination of walkability for megacities is critically important, particularly in the context of fostering sustainable urban environments. This paper applies modified Delphi techniques to focus on identifying and prioritizing the key factors influencing urban walkability in large cities. The selected region of the Gulf Cooperation Council (GCC) served as the basis for this research, reflecting its unique socio-cultural and environmental challenges. A panel of local and international experts participated in the study, evaluating and ranking 111 walkability indicators categorized into five groups: cultural, functional, safety, aesthetic, and comfort. Two rounds of the Delphi survey were conducted, to obtain insights from professionals in urban planning, civil engineering, and related fields. The findings emphasize the critical role of sustainability in addressing the extreme nature of the GCC climate, highlighting the need for innovative and climate-responsive pedestrian infrastructure. Safety and environmental considerations were identified as essential for enhancing walkability and contributing to more sustainable and livable cities in the region. The study’s outcomes led to the development of a ‘walkability audit tool’ tailored to Gulf cities, which serves as a strategic guide for policymakers and urban planners to implement sustainable urbanization policies. By addressing the relationship between walkability and sustainability, this research contributes to creating resilient, inclusive, and walkable urban environments that are better equipped to meet the challenges of rapid urbanization and climate adaptation in the GCC region. The results obtained from this study provide actionable insights and practical tools for enhancing walkability and advancing sustainable urban development in the GCC and similar regions globally. Full article

This study seeks to examine the development of scientific literature concerning the Danube Delta, an exceptional ecosystem characterized by its rich biodiversity, which is facing challenges from both climate change and human activities. It aims to identify significant trends in research publications from 1862 to 2023. The methodology employed involves a thorough bibliometric examination of articles catalogued in the Scopus database, utilizing specific criteria to ensure the direct applicability of the research to the Danube Delta. The analysis centers on factors such as publication frequency, citation rates, as well as collaborations among institutions and across international borders, thus shedding light on the scientific contributions and their practical implications in protecting the region’s unique ecosystem. The research findings indicate a notable surge in scholarly interest in the Danube Delta, particularly amidst growing global concerns regarding climate change. Furthermore, it is observed that highly cited studies often address issues related to habitat preservation, human impacts, and strategies for adapting to changing environmental conditions. The significance of international collaboration emerges as a crucial aspect in enhancing the caliber and relevance of research, underscoring the necessity for a coordinated global endeavor to study and safeguard this vital ecosystem. The research emphasizes the necessity of adopting a comprehensive and interdisciplinary methodology in studying the Danube Delta, offering insights for crafting conservation policies that address both local and global environmental concerns. Its findings offer a robust framework for steering future research endeavors and conservation initiatives, underscoring the crucial significance of international scientific cooperation in sustainably managing biodiversity amidst climate change challenges. While the study offers valuable insights, it is essential to acknowledge certain limitations, like underrepresentation of non-English language studies and methodological or modeling limitations. By acknowledging these limitations and exploring the suggested research avenues, future studies can further enhance our comprehension and management of the Danube Delta within the context of prevailing and forthcoming global challenges. Full article

Condition surveys are an important part of the whole scientific research of torso buildings, which we understand to be buildings with usually missing roofs, wooden ceilings, doors, windows, and other envelope constructions along with damaged internal and external infrastructure and surfaces. The aim of the processed condition surveys is to gather basic data on the technical state of the buildings. Torso buildings are, in our environment, especially the ruins of castles and manor houses, but also some churches, the remains of industrial enterprises, or even others. The proposed condition surveys can be used at any of them, not only in our country, but also in any other country of the world. The processed system of condition surveys allows us to anticipate further damage to architectural heritage buildings caused by their aging. It can contribute in a major way to the identification of eventual construction risks and to anticipate them. Condition surveys are designed as a quick, cheap, and easy to handle way to gather the basic overview needed for undertaking a basic stabilization of the most endangered parts of the ruins. In the next step, further scientific research using instruments i.e., in laboratories, can be undertaken. It is also important to know which parts of the torso buildings are dangerous and can endanger not only visitors, but also scientists realizing research on site. The first goal of the project focused on bettering of the stability of the torso buildings, especially ruins of castles, which was granted by the Slovak Ministry of Culture to elaborate and prepare a system for the identification of the most endangered parts of the ruins, which are in danger of dilapidation soon. The second goal was focused on preparing source material for further scientific research of the torso architecture. Experts from the Faculty of Civil Engineering of the Slovak University of Technology, with the cooperation of experts from praxis and from the Architectural Heritage Protection Office prepared a system for judging the construction details of torso buildings from the point of view of their construction–technical state. The aim of this judging lies in identifying the parts of their constructions that are most endangered by decay. Based on the condition survey results, conservation activities can be organized to save valuable details of the torso buildings before destruction and to protect the visitors of such localities before injuries, maybe even tragic injuries. Full article

Water crises are prevalent globally, but effective water governance can help mitigate these issues. This study, conducted in Soc Trang, a coastal province of the Vietnamese Mekong Delta, assessed water governance trends and identified local challenges using the OECD (Organization for Economic Cooperation and Development) water governance framework, which comprises 12 principles. Data were gathered through 15 questionnaires and two focus group discussions with the Department of Natural Resources and Environment and the Department of Agriculture and Rural Development. The findings indicate that all 12 principles have improved over the past decade, particularly in areas such as data management, the clarity of roles, appropriate basin scales, and innovative governance approaches. However, challenges remain, including external risks, limited human resources, ineffective coordination, and insufficient funding and facilities. While the OECD framework offers a comprehensive guide for water governance, it is crucial to provide clear explanations to local stakeholders during implementation. This ensures a shared understanding throughout the assessment process. A key aspect of this is translating scientific and technical terms into the local language and context, which enhances communication and engagement among all participants involved in the study. Full article

Precise cooperative node localization is essential for the application of multifunctional integrated radio frequency (RF) sensor networks in military and civilian domains. Most geometric localization methods commonly rely on observation data from multiple receiving nodes or anchor points with known positions and synchronized clocks, producing complex system architectures and high construction costs. To address this, our paper proposes an effective single-station cooperative node localization technique, where the observation station only requires two antennas for operation. Leveraging prior knowledge of the geometry of surrounding structures, multiple virtual stations (VSs) are constructed by mining the spatiotemporal information contained in the multipath components (MPCs) to realize target positioning. The proposed method consists of two steps. In the first step, an unambiguous dual-antenna direction-finding algorithm is designed to extract the spatial information of MPCs and construct VSs, allowing a preliminary estimate of the source position (SP). In the second step, the path delays are extracted via matched filtering, while the spatiotemporal information is correlated based on the energy distribution for a more precise SP estimation. Simulations and experimental results demonstrate that our algorithm achieves high-precision single-station localization for a collaborative node, with positioning accuracy typically within $0.1$ m. Full article

This paper addresses the author’s current understanding of the physics of interactions in polymers under a voltage field excitation. The effect of a voltage field coupled with temperature to induce space charges and dipolar activity in dielectric materials can be measured by very sensitive electrometers. The resulting characterization methods, thermally stimulated depolarization (TSD) and thermal-windowing deconvolution (TWD), provide a powerful way to study local and cooperative relaxations in the amorphous state of matter that are, arguably, essential to understanding the glass transition, molecular motions in the rubbery and molten states and even the processes leading to crystallization. Specifically, this paper describes and tries to explain ‘interactive coupling’ between molecular motions in polymers by their dielectric relaxation characteristics when polymeric samples have been submitted to thermally induced polarization by a voltage field followed by depolarization at a constant heating rate. Interactive coupling results from the modulation of the local interactions by the collective aspect of those interactions, a recursive process pursuant to the dynamics of the interplay between the free volume and the conformation of dual-conformers, two fundamental basic units of the macromolecules introduced by this author in the “dual-phase” model of interactions. This model reconsiders the fundamentals of the TSD and TWD results in a different way: the origin of the dipoles formation, induced or permanent dipoles; the origin of the Wagner space charges and the T_g,ρ transition; the origin of the T_LL manifestation; the origin of the Debye elementary relaxations’ compensation or parallelism in a relaxation map; and finally, the dual-phase origin of their super-compensations. In other words, this paper is an attempt to link the fundamentals of TSD and TWD activation and deactivation of dipoles that produce a current signal with the statistical parameters of the “dual-phase” model of interactions underlying the Grain-Field Statistics. Full article

A sport is a specific human activity with deep cultural and social meanings that involves cooperation and competitiveness according to well-established rules. One of the most representative sports at the local and global levels is football thanks to the large number of people and resources involved in supporting it. The aim of the study is to explore the connection between communities and football stadiums at a spatial level (development region, county and cities). From a methodological point of view, multicriteria analysis (eight criteria, four for the population and four for football stadiums) was utilized to determine and define the various relationships between the population and football stadiums. The obtained results highlighted, at the spatial level, the existence of some non-correlations between the population and football stadiums. Thus, the existence of strong relationships at the level of development regions (75%), followed by those established at the level of cities (24.1) and counties (2.4), were identified. The strongest relationships were established in the Northwest, Central and South development regions; in Bihor County and in cities like Bucharest, Brașov, Constanta and Iași. Full article

In a political climate of social polarization and distrust in public institutions, which in turn fosters misinformation, the European Union (EU) faces the challenge of becoming closer to its citizens. At the same time, the EU has well-established collaboration mechanisms at the local and regional levels. In this context, this study aims to analyze the Euroregions project, one of the strategies used by the EU to manage the different regions of Europe through cross-border collaboration. Thus, the main objective of this study is to find out, using the social network X (formerly Twitter), the communication strategies deployed by the regional governments that make up each of the five Spanish Euroregions on institutions of cross-border cooperation. The results show that regional governments do not promote effective communication strategies to publicize these Euroregions. Rather, these governments try to communicate their management success, focusing their discourse on the issue of European funds and thus generating a situation of misinformation around the benefits of belonging to the European Union. Our findings contribute to the budding literature on regional European areas, arguing that certain political actions could ameliorate the feeling of disaffection of the population towards European institutions. Full article