Fragmentation Process Research Articles

Dynamic Analysis of a Long Run-Out Rockslide Considering Dynamic Fragmentation Behavior in Jichang Town: Insights from the Three-Dimensional Coupled Finite-Discrete Element Method

To clearly realize the dynamic process as well as the dynamic fragmentation behavior of a long run-out rockslide, a novel numerical method for landslide simulation of the coupled finite-discrete element method (FDEM) was applied and the Jichang rockslide was used as a case. The calibrated simulation result of the FDEM in a rockslide deposit corresponds well with the real rockslide deposit. The main run-out process of the rockslide lasts for 75 s and can be divided into acceleration and deceleration stages, which last for 33 s and 42 s, respectively. The maximum overall rockslide movement speed is 35 m/s while the partial sliding mass reaches 45 m/s. The fracturing, fragmentation, and disintegration processes of the sliding mass can be clearly observed from the dynamic scenarios. Fracture energy generated by rock fracturing constantly increases with time in a non-linear form. Of the total fracture energy, 54% is released in the initial 5 s because of fracturing, and 39% of the total fracture energy is released because of fragmentation and disintegration in the last 35 s. The accumulated friction energy increases in the whole run-out process, and its magnitude is much greater than the kinetic energy and fracture energy of the sliding mass.

The world and Russia in the environment of transformation: Is the economic recovery sustainable?

In 2023, there is an improvement in the trends of economic dynamics in the global economy, but there is a high probability that it will be only temporal. The processes of fragmentation of the world economy are intensifying, previous indicators of the state of the economy are becoming less informative. Regulators face a difficult choice regarding the mechanisms of economic policy. Russia is in no less difficult conditions, given the negative effect of the sanctions that are being implemented against it. Increasing the strength of the domestic economy and forming stable conditions in the financial market are the most important prerequisites for the successful solution of emerging problems.

Dual-Level Framework for OpenBIM-Enabled Design Collaboration

Design coordination and collaboration are crucial in the architecture, engineering, and construction (AEC) industries, necessitating the integration of diverse disciplines and expertise to achieve unified and functional designs. Traditionally, these disciplines operate in isolation, leading to a fragmented design process. Building Information Modeling (BIM), recognized for its collaborative capabilities, presents an opportunity to revolutionize traditional design practices. However, existing research on BIM primarily assumes an ideal environment where all major participants use BIM models, overlooking the dynamics of mixed 2D Computer-aided Design (CAD) and 3D BIM environments. Addressing this research gap, this study aims to establish a dual-level OpenBIM-enabled collaborative design framework, enhancing the design process across various disciplines. The study employs a case study approach, applying this framework to an airport project in Chengdu, China. The airport includes different corridors that are similar in scope and scale but distinct enough to allow for a comparative study. The results demonstrate a 27% faster completion rate, a 98% reduction in design errors, and improved user satisfaction with the proposed method. The paper concludes by discussing the limitations of the study and suggesting avenues for future research.

HARE: Unifying the Human Activity Recognition Engineering Workflow

Sensor-based human activity recognition is becoming ever more prevalent. The increasing importance of distinguishing human movements, particularly in healthcare, coincides with the advent of increasingly compact sensors. A complex sequence of individual steps currently characterizes the activity recognition pipeline. It involves separate data collection, preparation, and processing steps, resulting in a heterogeneous and fragmented process. To address these challenges, we present a comprehensive framework, HARE, which seamlessly integrates all necessary steps. HARE offers synchronized data collection and labeling, integrated pose estimation for data anonymization, a multimodal classification approach, and a novel method for determining optimal sensor placement to enhance classification results. Additionally, our framework incorporates real-time activity recognition with on-device model adaptation capabilities. To validate the effectiveness of our framework, we conducted extensive evaluations using diverse datasets, including our own collected dataset focusing on nursing activities. Our results show that HARE’s multimodal and on-device trained model outperforms conventional single-modal and offline variants. Furthermore, our vision-based approach for optimal sensor placement yields comparable results to the trained model. Our work advances the field of sensor-based human activity recognition by introducing a comprehensive framework that streamlines data collection and classification while offering a novel method for determining optimal sensor placement.

Abstract LB_A19: Genome-wide CRISPR/Cas9 screens for the identification of targeted vulnerabilties in PARP inhibitor-resistant PARG;BRCA2-deficient tumor cells: A focus on EXO1/FEN1-mediated DNA repair

Abstract Targeting poly(ADP-ribose) glycohydrolase (PARG) is currently explored as a therapeutic approach to treat various cancer types, but we have a poor understanding of the specific genetic vulnerabilities that would make cancer cells susceptible to such a tailored therapy. Moreover, the identification of such vulnerabilities is of interest to target BRCA2;p53-deficient tumors that have acquired resistance to poly(ADP-ribose) polymerase inhibitors (PARPi), through loss of PARG expression. Here, by performing whole genome CRISPR/Cas9 drop-out screens we identify various genes involved in DNA repair to be essential for the survival of PARG;BRCA2;p53-deficient cells. In particular, our findings reveal EXO1 and FEN1 as major synthetic lethal interactors to PARG loss. We provide evidence that PARG;BRCA2;p53-deficient cells exhibit compromised replication fork progression, DNA single-strand break repair and Okazaki fragment processing, alterations that exacerbate and become lethal upon EXO1/FEN1 inhibition. Since this sensitivity is dependent on BRCA2 defects, we propose EXO1/FEN1 targeting in PARPi-resistant tumors that have lost PARG activity. Moreover, EXO1/FEN1 targeting may be a useful strategy to enhance the effect of PARG inhibitors in HR-deficient tumors. Citation Format: Christina Andronikou, Kamila Burdova, Diego Dibitetto, Cor Lieftink, Roderick L. Beijersbergen, Hana Hanzlikova, Jos Jonkers, Sven Rottenberg. Genome-wide CRISPR/Cas9 screens for the identification of targeted vulnerabilties in PARP inhibitor-resistant PARG;BRCA2-deficient tumor cells: A focus on EXO1/FEN1-mediated DNA repair [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr LB_A19.

Lignin Modification for Enhanced Performance of Polymer Composites.

The biopolymer lignin, which is heterogeneous and abundant, is usually present in plant cell walls and gives them rigidity and strength. As a byproduct of the wood, paper, and pulp manufacturing industry, lignin ranks as the second most prevalent biopolymer worldwide, following cellulose. This review paper explores the extraction, modification, and prospective applications of lignin in various industries, including the enhancement of thermosetting and thermoplastic polymers, biomedical applications such as vanillin production, fuel development, carbon fiber composites, and the creation of nanomaterials for food packaging and drug delivery. The structural characteristics of lignin remain undefined due to its origin, separation, and fragmentation processes. This comprehensive overview encompasses state-of-the-art techniques, potential applications, diverse extraction methods, chemical modifications, carbon fiber utilization, and the extraction of vanillin. Moreover, the review focuses on the utilization of lignin-modified polymer blends across multiple manufacturing sectors, providing insights into the advantages and limitations of this innovative approach for the development of environmentally friendly materials.

A Soft Systems Methodology Application to Promote the Multidimensional Model of e-Government Project Management in Indonesia’s Construction Services

The Integrated Construction Services Information System (ICSIS) project is one of the Indonesian government's initiatives to meet public demand for better construction business services. Despite being in operation for approximately 6 (six) years, ICSIS performs poorly. Fragmented business processes, noninteroperable systems, and unaccountable data all demonstrate poor performance in this regard. With all the best efforts, ICSIS only reaches 12% of the total target users. This paper discusses a problem-structuring approach to problem analysis and comprehension, as well as the critical factors to consider through stakeholder interaction. From various perspectives, the results of this structuring phase using literature study, comparative analysis and soft systems methodology indicate that multidimensional factors must be considered in order to achieve the expected ICSIS values. This technique assists decision makers in developing a multidimensional model in ICSIS project management with the goal of fostering more dependable and long-term e-government in the construction services.

Numerical simulation study on mesoscopic metallic foam core sandwich panels under hypervelocity impact

Due to its lightweight and superior energy absorption characteristics, metallic foams are exceptionally suitable for the protective shielding of spacecraft against debris. The mesoscopic structure of such a foam plays a pivotal role in enhancing its outstanding protective performance. Numerical simulations permit us to explore the damage mechanism of its internal structure and the evolving characteristics of debris clouds. By adopting the three-dimensional Voronoi tessellation in conjunction with the algorithm of background mesh mapping, this study constructed mesoscopic finite element models that accurately reflect the internal randomness and variability in ligament width within the metallic foam. Subsequently, numerical simulations were executed employing the FE-SPH adaptive method within the LS-DYNA. Comparative experimental cases substantiated the validity of the simulations, and an exhaustive mesh sensitivity analysis was conducted. Optimizing results from these simulations following a normal impact, we delved into the propagation of stress waves within the foam core, alongside the subsequent internal structural damage. Furthermore, we explored the damage mechanism of foam sandwich panels subjected to hypervelocity impacts. According to the fragmentation process of the projectile and the evolution of debris clouds, it was discerned that the random internal structure of the foam engenders an asymmetric and skewed debris cloud, dispersing its energy and culminating in multiple concentrated particle clusters with a predilection towards a particular direction. Tracking the velocity fluctuations of these ‘dominant particles’ and the inflicted damage on the rear facesheet revealed that the agglomerated tiny fragments of the projectile are primarily responsible for perforating the rear facesheet.

Fracture development around wellbore excavation: Insights from a 2D thermo-mechanical FDEM analysis

Insights into fracture development and excavation damaged zone (EDZ) formation around wellbore excavation sites are essential for understanding wellbore stability. In this study, a novel thermo-mechanical scheme is implemented in the 2D combined finite-discrete element method (FDEM) to investigate the fracturing process around a wellbore in a high-temperature subsurface environment. The developed scheme captures the isotropic/anisotropic thermal conduction characteristics within the rock formation. The coupled scheme and stress distributions around the wellbore subject to in-situ stress, drilling mud pressure, and temperature changes are validated by closed-form solutions. Fracture development and progressive EDZ formation by various mechanisms are analyzed. The results show that for an unsupported wellbore, fractures initiate in the region of the most severe stress concentration due to excavation unloading and constitute an EDZ that resembles the logarithmic-spiral rupture zone captured by experimental observations and Mohr-Coulomb models, resulting in potential water inrush due to the significantly increased fracture transmissivity of the EDZ and wellbore collapse. The shape and extent of the EDZ for wellbore excavation in the layered rock mass are dominated by the stress redistribution and the presence of low-strength bedding planes favorably oriented for bedding slippage. The excavation unloading-induced stresses can be effectively counteracted by properly applying drilling mud pressure, and the disturbance of the stress field occurs only within a small region, greatly reducing the extension of the EDZ. Thermal contraction of the surrounding rock due to its convective interaction with the cold drilling mud induces extra fractures around the wellbore. The extension of the EDZ is greater with increased thermal expansivity of the rock formation. Overall, the results indicate that the adopted thermo-mechanical FDEM simulation can provide unique geomechanical insight into wellbore stability behavior analysis, in which explicit consideration of the fracturing and fragmentation processes is of great significance.

Fragmented areas due to agricultural activity: native vegetation dynamics at crop interface (Montecaseros, Mendoza, Argentina)

Plant communities fragmented by agricultural activities were analyzed in a 250-ha area in eastern plains of Montecaseros, Gral. San Martín Department, Mendoza, Argentina. A phytosociological method assessed different sites along a gradient of human intervention, from natural environments with no evidence of altered native vegetation to maximum farming modification, also including cleared and abandoned fields. Soil analyses supplemented the characterization of six plant communities. A scrubland physiognomy dominates the area, with species of the genera Larrea, Atriplex and Lycium. Tillage and crop abandonment can alter natural factors involved in soil formation, causing deterioration and exerting selective pressure on species colonizing these degraded environments. Evaluating natural vegetation before land clearing for agriculture is essential to assess, through species that indicate environmental conditions, edaphic limitations hindering crop establishment and affecting productivity. The conservation of natural communities on private lands destined for agriculture is valued. Plant communities fragmented by agricultural activities were analyzed in a 250-ha area in eastern plains of Montecaseros, Gral. San Martín Department, Mendoza, Argentina. A phytosociological method assessed different sites along a gradient of human intervention, from natural environments with no evidence of altered native vegetation to maximum farming modification, also including cleared and abandoned fields. Soil analyses supplemented the characterization of six plant communities. A scrubland physiognomy dominates the area, with species of the genera Larrea, Atriplex and Lycium. Tillage and crop abandonment can alter natural factors involved in soil formation, causing deterioration and exerting selective pressure on species colonizing these degraded environments. Evaluating natural vegetation before land clearing for agriculture is essential to assess, through species that indicate environmental conditions, edaphic limitations hindering crop establishment and affecting productivity. The conservation of natural communities on private lands destined for agriculture is valued. Highlights: This study aimed to characterize plant communities in natural and intervened environments, in a representative area of the fragmentation processes caused by agriculture in the Monte Province (Mendoza, Argentina). Plant biodiversity plays a strategic role in ecosystemic provision of goods and services necessary to human health and well-being. Cultivable land is a vulnerable and scarce resource, particularly in drylands, where ecosystems have low capacity for natural regeneration. Tillage and crop abandonment can alter natural factors involved in soil formation, causing deterioration and exerting selective pressure on species colonizing these degraded environments. In agricultural land, clearing can give rise to a mosaic of landscapes: productive crops merge with abandoned crops and fragments of natural fields. Evaluating natural vegetation before land clearing for agriculture is essential to assess, through species that indicate environmental conditions, edaphic limitations hindering crop establishment and affecting productivity. Studies of vegetation dynamism in private lands contribute to plan and implement sustainable land management, tending to recover and conserve biodiversity in degraded soils, considering all associated ecosystem services.

Evolution characteristics of micromechanics provides insights into the microstructure of pharmaceutical tablets fabricated by bimodal mixtures

This research focuses on the evolution of mechanical behavior of bimodal mixtures undergoing compaction and diametrical compression. The clusters were built and discrete element method (DEM) was used to investigate the densification process and micromechanics of bimodal mixtures. Additionally, a more comprehensive investigate of the respective breakage of the bimodal mixtures has been carried out. On this basis, qualitative and quantitative analysis of the compressive force, force chain, contact bonds and density field evolution characteristics of the clusters are investigated during the compression process. The entire loading process of the clusters is divided into three stages: rearrangement, breakage and elastic–plastic deformation. Additionally, there are differences in the evolution of micromechanics behavior of different particles in the bimodal mixture, with pregelatinized starch breakage and deformation occurring before microcrystalline cellulose. With the tablet deformation, the fragmentation process of the tablet started at the point of contact and extended toward the center, and the curvature of the force chain increased. This approach may potentially hold a valuable new information relevant to important transformation forms batch manufacturing to advanced manufacturing for the oral solid dosage form.

On hierarchical clustering-based approach for RDDBS design

Distributed database system (DDBS) design is still an open challenge even after decades of research, especially in a dynamic network setting. Hence, to meet the demands of high-speed data gathering and for the management and preservation of huge systems, it is important to construct a distributed database for real-time data storage. Incidentally, some fragmentation schemes, such as horizontal, vertical, and hybrid, are widely used for DDBS design. At the same time, data allocation could not be done without first physically fragmenting the data because the fragmentation process is the foundation of the DDBS design. Extensive research have been conducted to develop effective solutions for DDBS design problems. But the great majority of them barely consider the RDDBS's initial design. Therefore, this work aims at proposing a clustering-based horizontal fragmentation and allocation technique to handle both the early and late stages of the DDBS design. To ensure that each operation flows into the next without any increase in complexity, fragmentation and allocation are done simultaneously. With this approach, the main goals are to minimize communication expenses, response time, and irrelevant data access. Most importantly, it has been observed that the proposed approach may effectively expand RDDBS performance by simultaneously fragmenting and assigning various relations. Through simulations and experiments on synthetic and real databases, we demonstrate the viability of our strategy and how it considerably lowers communication costs for typical access patterns at both the early and late stages of design.

Intramolecular interactions and the neutral loss of ammonia from collisionally activated, protonated ω-aminoalkyl-3-hydroxyfurazans.

Gas phase fragmentation reactions of monoprotonated 4-(3-aminopropyl)- and 4-(4-aminobutyl)-3-hydroxyfurazan were investigated to examine potential interactions between functional groups. The two heterocyclic alkyl amines were ionized by electrospray ionization (ESI, positive mode) and fragmented using tandem mass spectrometry (MS/MS). The fragmentation pathways were characterized using pseudo MS3 experiments, precursor-ion scans, and density functional computations. For both heterocyclic ions, loss of ammonia was the only fragmentation process observed at low collision energies. Computational analysis indicated that the most feasible mechanism was intramolecular nucleophilic displacement of ammonia from the protonated ω-aminoalkyl side chain by N5 of the furazan ring. The alkylated nitrogen in the resulting bicyclic product ion facilitated N-O bond cleavage; subsequent neutral losses of nitric oxide (NO) and carbon monoxide (CO) occurred by homolytic bond cleavages. Next in the multistep sequence, neutral loss of ethylene from a radical cation was observed. A less favorable, competing fragmentation pathway of protonated 4-(3-aminopropyl)-3-hydroxyfurazan was consistent with cleavage of the 3-hydroxyfurazan ring and losses of NO and CO. Overall, the similar fragmentation behavior found for protonated 4-(3-aminopropyl)- and 4-(4-aminobutyl)-3-hydroxyfurazan differed from that previously characterized for furazan analogs with shorter alkyl chains. These observations demonstrate that a small change in the structure of multifunctional, heterocyclic alkyl amines may significantly influence interactions between distinct functional groups and the nature of the fragmentation process.

Numerical analysis method of equivalent deformation parameters for grouted arch dam abutment fractured rock masses considering scale effects and anisotropy

Research on the equivalent deformation parameters of grouted arch dam abutment rock masses has recently emerged as a key in the design, construction and stability assessment of arch dams. With the aim of synthetically considering scale effects and anisotropy of the rock mass equivalent deformation parameters after grouting, in this paper, a practical numerical calculation method is developed. First, the Latin hypercube sampling method is introduced to generate a network of fractures of the arch dam abutment rock mass. Subsequently, the finite element models of the rock masses with different sizes in various directions are constructed. On this basis, equivalent continuum theory and cohesive element model are applied for numerical calculation of grouting fractured rock masses. Then, the scale effect and anisotropy of the deformation modulus of rock mass under different grouting conditions are investigated. Finally, the Jinping super-high arch dam is taken as an example to validate the theoretical significance and application effect of the proposed method. The analysis results indicate that the process of fracture and fragmentation of grouted rock masses is characterized precisely, and the deformation of material units can be described as fully as possible to calculate more realistic equivalent deformation parameters of the fractured rock masses.

Circulating cell-free DNA fragmentation is a stepwise and conserved process linked to apoptosis

BackgroundCirculating cell-free DNA (cfDNA) is a pool of short DNA fragments mainly released from apoptotic hematopoietic cells. Nevertheless, the precise physiological process governing the DNA fragmentation and molecular profile of cfDNA remains obscure. To dissect the DNA fragmentation process, we use a human leukemia cell line HL60 undergoing apoptosis to analyze the size distribution of DNA fragments by shallow whole-genome sequencing (sWGS). Meanwhile, we also scrutinize the size profile of plasma cfDNA in 901 healthy human subjects and 38 dogs, as well as 438 patients with six common cancer types by sWGS.ResultsDistinct size distribution profiles were observed in the HL60 cell pellet and supernatant, suggesting fragmentation is a stepwise process. Meanwhile, C-end preference was seen in both intracellular and extracellular cfDNA fragments. Moreover, the cfDNA profiles are characteristic and conserved across mammals. Compared with healthy subjects, distinct cfDNA profiles with a higher proportion of short fragments and lower C-end preference were found in cancer patients.ConclusionsOur study provides new insight into fragmentomics of circulating cfDNA processing, which will be useful for early diagnosis of cancer and surveillance during cancer progression.

Decreased species richness along bare patch gradient in the degradation of Kobresia pasture on the Tibetan Plateau

The Kobresia pasture in the Tibetan Plateau, as the world's largest and most unique pastoral alpine ecosystem, is undergoing severe degradation, visible in the formation of bare patches. Characteristics of bare patches in Kobresia pastures are regarded as indicators of the fragmentation and degradation of the alpine landscapes. Here, we used unmanned aerial vehicles (UAV)-based low-elevation remote sensing to monitor 72 study sites in the eastern Tibetan Plateau for identifying the spatial patterns of bare patches of Kobresia pasture degradation on regional scale. We conducted field surveys of species composition, quantified fragmentation caused by bare patches using four landscape indices (patch area, total edge length, shape index and splitting index, representing the patch area, length of the edge, shape, and dispersion of the bare patches, respectively), then modeled the response of plant species richness and productivity at the scale of 50 × 50 m to the Kobresia pasture fragmentation process. Our results indicated that species richness and biomass production decreased significantly with each increasing bare patch index. The total edge length of bare patches increased the spatial turnover of plant species. Although bare patch area significantly decreased the species richness of plant communities, it led to a decrease in forb richness and an increase in grass richness along the degradation of Kobresia pastures.Bare patch areas, as the most easily accessible and highly accurate parameter by UAV-based low-elevation remote sensing, significantly related to the decrease in species richness and productivity, and mainly explained the changes in functional group composition. For assessing the ecological integrity of grassland functionality (plant species diversity and above-ground productivity), bare patch area can be used as an important indicator of Kobresia pasture degradation.

Therapeutic success in fragmented coronoid process disease and other canine medial elbow compartment pathology: a systematic review with meta-analyses.

The correct treatment of elbow dysplasia is controversial in modern small animal orthopedics. The aim of this study was to compile all relevant literature of the therapy of fragmented coronoid process and other hereditary disorders of the medial elbow compartment and to statistically evaluate the therapeutic results in three meta-analyses. The basis for the systematic literature review was a comprehensive database search of Web of Science, PubMed and Medline. Studies on living patients with above mentioned degenerative joint disease were included in the initial literature search. The data from the final studies, selected according to the PRISMA guidelines, was subsequently extracted. Finally, the success of the different therapies was compared and analyzed by three meta-analyses: success rate, mean difference and standardized mean difference. Fourteen of 494 publications covered by the systematic literature search remained. Their overall truth was: In studies where surgery outcomes was determined by clinical examination and owner questionnaires, it was found that surgical intervention had a significant positive outcome in the presence of fragmented coronoid process and medial compartment disease. Surgical outcomes were also good in three cross-over studies that investigated treatment success using computerized gait analysis. In contrast, comparative studies between surgical and conservative management yielded controversial results. The meta-analysis found no significant difference between medical and surgical therapy. The positive results of studies investigating owner satisfaction and veterinary clinical examination of surgical therapy for medial compartment disease were confirmed by two meta-analyses. However, their study designs were susceptible to observer biases. A third meta-analysis of standardized mean difference differentiating computerized gait analysis results of surgical and conservative management found no evidence of significant superiority of each treatment modality. It however had a limited number of subjects. More comparative studies of high evidence are needed to better understand medial compartment disease and provide the clinician with more accurate diagnostics to separate pathology that should be treated surgically from pathology that can benefit from conservative therapy similarly. Given the invasiveness a more cautious approach might be warranted regarding generally recommending surgery for pathology of the medial elbow compartment.

Dynamics of the Policy Network in the Aspect of Global Crisis Phenomena (On the Example of NATO)

Introduction. A peculiarity of modern political reality is the interconnectedness of the processes of globalization and fragmentation in the world. In a new emerging paradigm of international relations, policy networks come to the fore. These are the network structures for managing public affairs, uniting a variety of political actors. The relevance of the study is due to the need for an objective evaluation of the development of the policy network in the context of global changes as well as forecasting potential threats in the field of international security. The aim of the work is to examine the dynamics of the policy network in the context of global crisis phenomena, using the example of the North Atlantic Treaty Organization. Methods. The theoretical basis of the research is the network approach and the concept of policy networks, which allow us to study the object from an interdisciplinary point of view and conduct structural studies at all levels of analysis. The complexity of the structure of policy networks requires the use of methods of scientific cognition – analysis and synthesis, media analytics such as the research of content, and expert opinions. Analysis. The policy network is characterized both by the resilience and stability of its structure, which allows it to function effectively in internal and external transformations, and by the complexity of the relations among its actors. Global policy networks are formed on the principles of mutually beneficial resource exchange to achieve common goals and solve individual problems. An example of how NATO has been functioning in the period 2020–2023 showcases trends towards the transformation of the policy network from disintegration to subsequent reintegration to obtain the desired result. In a crisis situation, NATO as a global policy network is experiencing the dynamics of “connected instability”, establishing new forms of actor relationships that require flexibility in political decision-making. Results. In conditions of global instability and uncertainty, policy networks play a supporting (safety-maintaining) role in the processes of supranational regulation, contributing to the creation of an effective architecture of multi-level governance. As a result of the research, the author comes to the conclusion that it is necessary to update the theory of the network approach to further develop mechanisms for describing the actors’ cooperation within the policy network.

Invariance principle for fragmentation processes derived from conditioned stable Galton–Watson trees

Invariance principle for fragmentation processes derived from conditioned stable Galton–Watson trees

Fragmentation process of soil aggregates under concentrated water flow in red soil hilly region with different land use patterns

Fragmentation process of soil aggregates under concentrated water flow in red soil hilly region with different land use patterns