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ABSTRACT The deep‐sea benthos often exhibit exceptional biodiversity. The patch‐mosaic hypothesis proposes that this deep‐sea diversity arises from varied microhabitats with prolonged temporal persistence filtering for distinctive communities thereby increasing beta‐diversity. This study investigated environmental, community, and macrofaunal species turnover at four deep‐sea sites (~2000 m) in the northern Gulf of Mexico. Using precise small‐scale sampling with a ROV, we analyzed patterns across spatial scales from centimeters to approximately 400 km among 67 sediment cores. We examined the relationships between sedimentary carbon, sediment grain size, and macrofaunal alpha‐ and beta‐diversity. Subsequently, we explored the role of these environmental properties and their spatial arrangement in shaping communities and species distributions. We observed a consistent trend where the overall abundance and diversity of a community increased with higher carbon but decreased with increasing grain size. Substantial faunal turnover was observed among cores, even at centimeter scales, with the contribution of centimeter‐scale spatial distance rivaling that of 100‐km scales in faunal dissimilarity. Similar to alpha‐diversity, beta‐diversity exhibited strong correlations with sediment carbon and grain size. The observed random spatial structure in grain size and carbon appear to translate into randomness in both community and species distribution. These findings align with the patch‐mosaic model, underscoring the complexity of deep‐sea ecosystems. These findings suggest an intricate relationship between sedimentary attributes, faunal composition, and spatial arrangement in the deep‐sea benthos, shedding light on the mechanisms driving biodiversity in seemingly homogeneous environments. [ABSTRACT FROM AUTHOR]

Social and spatial structures of host populations play important roles in pathogen transmission. For environmentally transmitted pathogens, the host space use interacts with both the host social structure and the pathogen's environmental persistence (which determines the time-lag across which two hosts can transmit). Together, these factors shape the epidemiological dynamics of environmentally transmitted pathogens. While the importance of both social and spatial structures and environmental pathogen persistence has long been recognized in epidemiology, they are often considered separately. A better understanding of how these factors interact to determine disease dynamics is required for developing robust surveillance and management strategies. Here, we use a simple agent-based model where we vary host mobility (spatial), host gregariousness (social) and pathogen decay (environmental persistence), each from low to high levels to uncover how they affect epidemiological dynamics. By comparing epidemic peak, time to epidemic peak and final epidemic size, we show that longer infectious periods, higher group mobility, larger group size and longer pathogen persistence lead to larger, faster growing outbreaks, and explore how these processes interact to determine epidemiological outcomes such as the epidemic peak and the final epidemic size. We identify general principles that can be used for planning surveillance and control for wildlife host–pathogen systems with environmental transmission across a range of spatial behaviour, social structure and pathogen decay rates. This article is part of the theme issue 'The spatial–social interface: a theoretical and empirical integration'. [ABSTRACT FROM AUTHOR]

Understanding spatial variation in species distribution and community structure is at the core of community ecology. Nevertheless, the effect of distance on metacommunity structure remains little studied. We examine how plant‐pollinator community structure changes across geographical distances at a regional scale and disentangle its underlying local and regional processes.We use a multilayer network to represent linked plant‐pollinator communities as a metacommunity in the Canary Islands. We used modularity (i.e. the extent to which the community is partitioned into groups of densely interacting species) to quantify distance decay in structure across space. In multilayer modularity, the same species can belong to different modules in different communities, and modules can span communities. This enabled quantifying how similarity in module composition varied with distance between islands. We developed three null models, each controlling for a separate component of the multilayer network, to disentangle the role of species turnover, interaction rewiring and local factors in driving distance decay in structure.We found a pattern of distance decay in structure, indicating that islands tended to share fewer modules with increasing distance. Species turnover (but not interaction rewiring) was the primary regional process triggering distance decay in structure. Local interaction structure also played an essential role in determining the structure similarity of communities at a regional scale. Therefore, local factors that determine species interactions occurring at a local scale drive distance decay in structure at a regional scale.Our work highlights the interplay between local and regional processes underlying community structure. The methodology, and specifically the null models, we developed provides a general framework for linking communities in space and testing different hypotheses regarding the factors generating spatial structure. [ABSTRACT FROM AUTHOR]

Background: Populations of Olea europaea subsp. europaea var. sylvestris, the ancestor of cultivated olives, are scattered across the Mediterranean Basin. However, after millennia of possible hybridization with cultivated varieties, the genetic identity of many of these populations remain questionable. In the southern Levant, the plausible primary domestication center of olives, many of the naturally growing olive (NGOs) are considered feral, having developed from nearby olive groves. Here, we investigated the genetic identity of NGOs population in the Carmel region, hypothesizing that their specific location, which limit anemophily, provided an opportunity for the persistence of genuine var. sylvestris. Results: We mapped more than 1,000 NGOs on the Kurkar ridge along the Carmel coast, within and outside the residential area of Atlit and used simple sequence repeats of 14 loci to assess the spatial genetic structure of 129 NGOs. Genetic diversity parameters and genetic distances between NGO and cultivated olives, as well as phenotypic and morphometric analyses of their oil content and pits, respectively, indicated the presence of a genuine var. sylvestris population. However, NGOs within the residential area of Atlit and old settlements showed an intermediate admix genetic structure, indicating on hybridization with local varieties, a consequence of their proximity to cultivated trees. Conclusions: Integrating the results of genetic and phenotypic analyses we provide crucial evidence of the presence of a genuine var. sylvestris population in the southern Levant, in close geographical proximity to archaeological sites with the earliest evidence of olive exploitation in the ancient world. We supplement the results with recommendations for a conservation program that combines municipal requirements and the urgent need to preserve the largest population of var. sylvestris in the southern Levant. [ABSTRACT FROM AUTHOR]

Deciding where to forage must not only account for variations in habitat quality but also where others might forage. Recent studies have suggested that when individuals remember recent foraging outcomes, negative frequency-dependent learning can allow them to avoid resources exploited by others (indirect competition). This process can drive the emergence of consistent differences in resource use (resource partitioning) at the population level. However, indirect cues of competition can be difficult for individuals to sense. Here, we propose that information pooling through collective decision-making—i.e. collective intelligence—can allow populations of group-living animals to more effectively partition resources relative to populations of solitary animals. We test this hypothesis by simulating (i) individuals preferring to forage where they were recently successful and (ii) cohesive groups that choose one resource using a majority rule. While solitary animals can partially avoid indirect competition through negative frequency-dependent learning, resource partitioning is more likely to emerge in populations of group-living animals. Populations of larger groups also better partition resources than populations of smaller groups, especially in environments with more choices. Our results give insight into the value of long- versus short-term memory, home range sizes and the evolution of specialization, optimal group sizes and territoriality. This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'. [ABSTRACT FROM AUTHOR]

Deciding where to forage must not only account for variations in habitat quality but also where others might forage. Recent studies have suggested that when individuals remember recent foraging outcomes, negative frequency-dependent learning can allow them to avoid resources exploited by others (indirect competition). This process can drive the emergence of consistent differences in resource use (resource partitioning) at the population level. However, indirect cues of competition can be difficult for individuals to sense. Here, we propose that information pooling through collective decision-making—i.e. collective intelligence—can allow populations of group-living animals to more effectively partition resources relative to populations of solitary animals. We test this hypothesis by simulating (i) individuals preferring to forage where they were recently successful and (ii) cohesive groups that choose one resource using a majority rule. While solitary animals can partially avoid indirect competition through negative frequency-dependent learning, resource partitioning is more likely to emerge in populations of group-living animals. Populations of larger groups also better partition resources than populations of smaller groups, especially in environments with more choices. Our results give insight into the value of long- versus short-term memory, home range sizes and the evolution of specialization, optimal group sizes and territoriality. This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'. [ABSTRACT FROM AUTHOR]

Mediterranean lagoons face a significant threat due to the prevalent risks of eutrophication and dystrophy, particularly in sectors with limited water renewal. The El Mellah Lagoon in northeastern Algeria represents a crucial ecosystem. Our study focused on assessing its operational state by examining the seasonal variability of spatial patterns indicative of eutrophication. Our primary hypothesis posited that a lack of fluctuation in spatial pattern expression reflects ecosystem dysfunction in the face of eutrophication-related disturbances. Our objective was to establish that the El Mellah Lagoon maintains robust health, capable of recovering or sustaining dynamic equilibrium following periods of instability induced by external or internal disruptions. To achieve this, we employed a methodology combining multidimensional analysis (utilizing STATIS from the K-TABLE family) and spatial analysis (employing Moran's I and ordinary Kriging interpolation). Statistical analyses of physicochemical and biological measurements revealed seasonal variations in key eutrophication parameters. The first principal components derived from the STATIS analysis underwent spatial analysis techniques. Consequently, the spatial models constructed unveiled the dynamics characterizing the operational states of the El Mellah Lagoon. This comprehensive approach aimed to demonstrate the lagoon's resilience and ability to withstand disturbances, fostering a dynamic equilibrium crucial for its long-term viability. [ABSTRACT FROM AUTHOR]

Intra‐tumour immune infiltration is a crucial determinant affecting immunotherapy response in non‐small cell lung cancer (NSCLC). However, its phenotype and related spatial structure have remained elusive. To overcome these restrictions, we undertook a comprehensive study comprising spatial transcriptomic (ST) data (28 712 spots from six samples). We identified two distinct intra‐tumour infiltration patterns: immune exclusion (characterised by myeloid cells) and immune activation (characterised by plasma cells). The immune exclusion and immune activation signatures showed adverse and favourable roles in NSCLC patients' survival, respectively. Notably, CD14+APOE+ cells were recognised as the main cell type in immune exclusion samples, with increased epithelial‒mesenchymal transition and decreased immune activities. The co‐location of CD14+APOE+ cells and MMP7+ tumour cells was observed in both ST and bulk transcriptomics data, validated by multiplex immunofluorescence performed on 20 NSCLC samples. The co‐location area exhibited the upregulation of proliferation‐related pathways and hypoxia activities. This co‐localisation inhibited T‐cell infiltration and the formation of tertiary lymphoid structures. Both CD14+APOE+ cells and MMP7+ tumour cells were associated with worse survival. In an immunotherapy cohort from the ORIENT‐3 clinical trial, NSCLC patients who responded unfavourably exhibited higher infiltration of CD14+APOE+ cells and MMP7+ tumour cells. Within the co‐location area, the MK, SEMA3 and Macrophage migration inhibitory factor (MIF) signalling pathway was most active in cell‒cell communication. This study identified immune exclusion and activation patterns in NSCLC and the co‐location of CD14+APOE+ cells and MMP7+ tumour cells as contributors to immune resistance. [ABSTRACT FROM AUTHOR]

Objectives: Building aggregation is one of the main contents in map generalization at the micro scale, which is of great significance to map compilation and multi-scale representation of spatial data. In order to maintain the consistency of spatial characteristics, a building aggregation method considering the spatial structure is proposed. Methods: First, based on distance-adaptive Delaunay triangles, the relationships of spatial structure between adjacent buildings are divided into six types. Meanwhile, these spatial structures are summarized as positive bridging type and oblique bridging type according to the bridging surfaces. Then, the bridging area is constructed according to bridging triangles, which are identified by projective overlap lines between adjacent buildings. The rectangular method is applied to the bridging area to maintain the spatial structure relationship. Finally, the calculation of bridging distance between adjacent buildings is put forward for building clustering, which can meet the mapping requirements and cognitive habits. Results: The effectiveness and universality of the proposed method are verified by several experiments. Conclusions: The comparative experiment shows that the proposed method has advantages in maintaining spatial structure characteristics and geometrical characteristics, including area consistency and rectangularity. [ABSTRACT FROM AUTHOR]

Kin selection is important for understanding the evolution of social behaviour in group-living species. Yet, the role of kinship in solitary species has received little attention. We studied how kinship influences intraspecific variation in social organization and spatial structure in a predominantly solitary species, the bush Karoo rat, Otomys unisulcatus , from the Succulent Karoo semidesert of South Africa. We predicted that if social groups occur, they should consist of close kin. We further predicted that the spatial structure is not random, but that close kin live closer to each other. Over 5 years we performed trapping and focal animal observations and fitted mini-GPS dataloggers simultaneously on 125 neighbouring female bush Karoo rats to investigate how their spatial structure was influenced by kinship. Females were mainly solitary, although small social groups also occurred, all consisting of close kin, typically females, such as a mother and her adult daughter or sisters. Although females did have more nonkin than kin neighbours, kin lived closer to each other than nonkin. Daily ranges were larger in the breeding than in the nonbreeding season and overlapped more between kin than nonkin females. We conclude that kinship should be considered when studying solitary species as it might influence variation in social organization and spatial structure. • This study is the first use of mini-GPS devices in a small rodent. • Female bush Karoo rat females are mainly solitary. • Sometimes they form small groups, always consisting of close kin. • They display a kinship spatial structure. • Kinship is important to understand solitary species' social system. [ABSTRACT FROM AUTHOR]

This paper employs the instrumental variable method and the intermediary model to explore the influence of monocentric and polycentric spatial structures of innovation agglomeration on energy efficiency. This paper uses data from 2010 to 2021 in China, and also panel data regression models were used. The findings indicate that the monocentric spatial structure of provincial system innovation agglomeration is primarily concentrated in northeastern and western regions of China, whereas the polycentric spatial structure is mainly distributed in eastern coastal areas. A monocentric spatial structure inhibits the enhancement of energy efficiency, but there is an environmental paradox of excessive resource agglomeration. In contrast, a polycentric spatial structure and its strengthening tendency facilitate the improvement of energy efficiency. A monocentric spatial structure has an inhibitory impact on the improvement of energy efficiency in the three sectors of agriculture, industry, and construction, while a polycentric spatial structure aids it. A monocentric spatial structure further hinders the improvement of energy efficiency by impeding the upgrading of the industrial structure, while the upgrading of the industrial structure driven by the polycentric spatial structure plays a role in enhancing energy efficiency. The policy recommendations of this paper are intended to help coordinate the pace of innovation development between cities, adjust the spatial structure of innovation agglomeration between regions, and promote the upgrading of the comprehensive industrial structure, thereby improving overall energy efficiency. [ABSTRACT FROM AUTHOR]

The study presents a thorough and detailed analysis of bicalutamide's structural and conformational properties. Quantum chemical calculations were employed to explore the conformational properties of the molecule, identifying significant energy differences between conformers. Analysis revealed that hydrogen bonds stabilise the conformers, with notable variations in torsion angles. Conformers were classified into 'closed' and 'open' types based on the relative orientation of the cyclic fragments. NOE spectroscopy in different solvents (CDCl3 and DMSO-d6) was used to study the conformational preferences of the molecule. NOESY experiments provided the predominance of 'closed' conformers in non-polar solvents and a significant presence of 'open' conformers in polar solvents. The proportions of open conformers were 22.7 ± 3.7% in CDCl3 and 59.8 ± 6.2% in DMSO-d6, while closed conformers accounted for 77.3 ± 3.7% and 40.2 ± 6.2%, respectively. This comprehensive study underscores the solvent environment's impact on its structural behaviour. The findings significantly contribute to a deeper understanding of conformational dynamics, stimulating further exploration in drug development. [ABSTRACT FROM AUTHOR]

During February 2023, the quasi‐4‐day wave (Q4DW) with westward zonal wavenumber 2 (W2) reached its largest amplitude of ∼400 m in the Southern Hemisphere (SH) geopotential height observations since 2004, which occurred simultaneously with an Arctic major sudden stratospheric warming (SSW) with an elevated stratopause (ES). However, the Q4DW‐W2 perturbations in the Northern Hemisphere (NH) were unexpectedly suppressed despite the unstable Arctic stratosphere and mesosphere during the 2023 ES‐SSW. Diagnostic analysis shows that the westward winds at ∼54°N–70°N in the upper stratosphere of ∼‐79 m/s during the 2023 ES‐SSW were the strongest during boreal winters over the past two decades, which benefited from the onset of a preceding minor SSW at the end of January. The strongest westward wind generated a wave geometry configuration of full reflection for Q4DW‐W2 in the NH, while the Q4DW‐W2 enhancement in the SH was induced by the in‐situ amplification of the surviving seeding perturbations. Plain Language Summary: Among the planetary waves with a period of about 4 days, the eastward quasi‐4‐day wave (Q4DW) excited by the double‐jet structure in the Southern Hemisphere is the most famous one, while another Q4DW with westward zonal wavenumber 2 (W2) belonging to the normal modes of the Earth's atmosphere has attracted little attention. During the February 2023 sudden stratospheric warming (SSW) with an elevated stratopause (ES), the exceptional enhancement and suppression of Q4DW‐W2 were captured in the Southern Hemisphere and Northern Hemisphere, respectively. Such global structure is first observed and abnormal among traveling planetary waves during SSW since they usually have a peak region in the unstable winter hemisphere. We found that the rare sequence of stratospheric disturbances in the 44‐year historical record that a minor SSW followed by an ES‐SSW led to the excessively strong westward wind during the 2023 ES‐SSW, which resulted in a wave geometry configuration of full reflection for Q4DW‐W2 in the Northern Hemisphere. Our current results well establish the relationship between a new global structure of traveling planetary waves during SSW and the rare sequence of stratospheric disturbances. This will deepen the understanding of the less studied Q4DW‐W2 and the Earth's whole atmospheric coupling during SSW. Key Points: The anomalous burst and suppression of quasi‐4‐day wave (Q4DW) with westward zonal wavenumber 2 (W2) were observed in the Southern Hemisphere and Northern Hemisphere (NH) respectively during the February 2023 major sudden stratospheric warming (SSW) with elevated stratopause (ES)The rare sequence of SSWs in January and February 2023 led to the strongest westward wind during boreal winters over the past two decadesThe strongest westward wind during the 2023 ES‐SSW created a wave geometry configuration of full reflection weakening the Q4DW‐W2 in the NH [ABSTRACT FROM AUTHOR]

Plants emit biogenic volatile organic compounds (BVOCs) as signaling molecules, playing a crucial role in inducing resistance against herbivores. Neighboring plants that eavesdrop on BVOC signals can also increase defenses against herbivores or alter growth patterns to respond to potential risks of herbivore damage. Despite the significance of BVOC emissions, the evolutionary rationales behind their release and the factors contributing to the diversity in such emissions remain poorly understood. To unravel the conditions for the evolution of BVOC emission, we developed a spatially explicit model that formalizes the evolutionary dynamics of BVOC emission and non‐emission strategies. Our model considered two effects of BVOC signaling that impact the fitness of plants: intra‐individual communication, which mitigates herbivore damage through the plant's own BVOC signaling incurring emission costs, and inter‐individual communication, which alters the influence of herbivory based on BVOC signals from other individuals without incurring emission costs. Employing two mathematical models—the lattice model and the random distribution model—we investigated how intra‐individual communication, inter‐individual communication, and spatial structure influenced the evolution of BVOC emission strategies. Our analysis revealed that the increase in intra‐individual communication promotes the evolution of the BVOC emission strategy. In contrast, the increase in inter‐individual communication effect favors cheaters who benefit from the BVOCs released from neighboring plants without bearing the costs associated with BVOC emission. Our analysis also demonstrated that the narrower the spatial scale of BVOC signaling, the higher the likelihood of BVOC evolution. This research sheds light on the intricate dynamics governing the evolution of BVOC emissions and their implications for plant–plant communication. [ABSTRACT FROM AUTHOR]

In the European Union, the consequences of population aging are generally visible, including the negative impact of dynamically rising aging index and old-age dependency ratio. Besides the growing number of elders, the basis of the problem spiral can be identified with the excessively low population of child cohorts (aged 0--14 years) entering the working-age group (aged 15--64 years). The focus of the study is on childbearing behavior, i.e. fertility, in a geographical based approach, at the level of NUTS 2 regions. According to the results, it can be concluded that the total fertility rate exchanged significantly regionally in the European Union between 2010 and 2020. The previously outstanding values of Western and Northern Europe have decreased significantly, the Central and Eastern European regions, which were in an unfavorable situation at the beginning of the decade, have made a significant progress, while the low values of 2010 of the southern regions decreased even further. The average age of women at childbirth shows smaller differences than the total fertility rate, as births were brought forward in only one percent of the regions; on the other hand, the average age of having children has shifted later at different paces in certain parts of the European Union. [ABSTRACT FROM AUTHOR]

The reasonable design of S‐scheme heterojunction to avoid unwanted charge transfer paths in hybrid semiconductors is considered to be an attractive method to obtain efficient photocatalytic hydrogen evolution activity. The photocatalytic hydrogen evolution performance of the system was improved by loading ultra‐thin InVO4 nanosheets on the surface of hollow cube Co3O4 to form an S‐scheme heterojunction. Benefiting from the unique nano‐cage structure derived from the zeolitic imidazolate frameworks (ZIF) series, it not only provides a good carrier for activating and stabilizing InVO4 nanosheets but also effectively avoids the masking of active sites caused by self‐agglomeration, which is more conducive to the exposure of more active sites. In the presence of sensitizer and sacrificial reagent, the optimized InVO4/Co3O4 has a more competitive H2 production, which is undoubtedly due to the construction of S‐scheme heterojunctions and unique spatial structure that facilitates the spatial separation of photoexcited charges. It is further confirmed that the photogenerated carrier transfer follows the S‐scheme mechanism by in‐situ irradiation XPS test. [ABSTRACT FROM AUTHOR]

Maintaining the stability of ecological communities is critical for conservation, yet we lack a clear understanding of what attributes of metacommunity structure control stability. Some theories suggest that greater dispersal promotes metacommunity stability by stabilizing local populations, while others suggest that dispersal synchronizes fluctuations across patches and leads to global instability. These effects of dispersal on stability may be mediated by metacommunity structure: the number of patches, the pattern of connections across patches, and levels of spatiotemporal correlation in the environment. Thus, we need theory to investigate metacommunity dynamics under different spatial structures and ecological scenarios. Here, we use simulations to investigate whether stability is primarily affected by connectivity, including dispersal rate and topology of connectivity network, or by mechanisms related to the number of patches. We find that in competitive metacommunities with environmental stochasticity, network topology has little effect on stability on the metacommunity scale even while it could change spatial diversity patterns. In contrast, the number of connected patches is the dominant factor promoting stability through averaging stochastic fluctuations across more patches, rather than due to more habitat heterogeneity per se. These results broaden our understanding of how metacommunity structure changes metacommunity stability, which is relevant for designing effective conservation strategies. [ABSTRACT FROM AUTHOR]

The work presents results of the in vitro and in silico study of formation of amyloid-like structures under harsh denaturing conditions by non-specific OmpF porin of Yersinia pseudotuberculosis (YpOmpF), a membrane protein with β-barrel conformation. It has been shown that in order to obtain amyloid-like porin aggregates, preliminary destabilization of its structure in a buffer solution with acidic pH at elevated temperature followed by long-term incubation at room temperature is necessary. After heating at 95°C in a solution with pH 4.5, significant conformational rearrangements are observed in the porin molecule at the level of tertiary and secondary structure of the protein, which are accompanied by the increase in the content of total β-structure and sharp decrease in the value of characteristic viscosity of the protein solution. Subsequent long-term exposure of the resulting unstable intermediate YpOmpF at room temperature leads to formation of porin aggregates of various shapes and sizes that bind thioflavin T, a specific fluorescent dye for the detection of amyloid-like protein structures. Compared to the initial protein, early intermediates of the amyloidogenic porin pathway, oligomers, have been shown to have increased toxicity to the Neuro-2aCCL-131™ mouse neuroblastoma cells. The results of computer modeling and analysis of the changes in intrinsic fluorescence during protein aggregation suggest that during formation of amyloid-like aggregates, changes in the structure of YpOmpF affect not only the areas with an internally disordered structure corresponding to the external loops of the porin, but also main framework of the molecule, which has a rigid spatial structure inherent to β-barrel. [ABSTRACT FROM AUTHOR]

Spatially resolved datasets are revolutionizing knowledge in molecular biology, yet are under-utilized for questions in evolutionary biology. To gain insight from these large-scale datasets of spatial organization, we need mathematical representations and modeling techniques that can both capture their complexity, but also allow for mathematical tractability. Evolutionary graph theory utilizes the mathematical representation of networks as a proxy for heterogeneous population structure and has started to reshape our understanding of how spatial structure can direct evolutionary dynamics. However, previous results are derived for the case of a single new mutation appearing in the population and the role of network structure in shaping fitness landscape crossing is still poorly understood. Here we study how network-structured populations cross fitness landscapes and show that even a simple extension to a two-mutational landscape can exhibit complex evolutionary dynamics that cannot be predicted using previous single-mutation results. We show how our results can be intuitively understood through the lens of how the two main evolutionary properties of a network, the amplification and acceleration factors, change the expected fate of the intermediate mutant in the population and further discuss how to link these models to spatially resolved datasets of cellular organization. [ABSTRACT FROM AUTHOR]

The cross-border mergers and acquisitions (M&A) of digital cultural enterprises have formed a "reticular space" between countries (regions) regarding advanced production factors such as capital, technology, and knowledge, and have an important impact on reshaping the economic geographic configuration of the world. Based on this, this paper used complex network methods and GIS spatial technology to explore the structure of global cross-border M&A network of digital cultural enterprises and its evolution law. The results show that: ① The crossborder M&A network of digital cultural enterprises is gradually evolving from a "dual-core" pattern dominated by North America and Western Europe to a "three-pole" pattern dominated by North America, Western Europe, and Asia-Pacific; ② The polarization caused by economic globalization has induced the phenomenon of "rich club" in the cross-border M&A network of digital cultural enterprises, and the centralization of the cross-border M&A network of global digital cultural enterprises has been deepening; ③ The refinement of the division of global labor system of digital cultural enterprises and the deepening of regional economic grouping and integration have enhanced the M&A preference and contact level between neighboring countries (regions); ④ The cross-border M&A network of digital cultural enterprises is characterized by a "core-periphery" structure. Among them, North America and Western Europe always occupy the core of the network; while Africa, Latin America, and Central Asia and West Asia are located at the edge of the network and are in a state of being "harvested". [ABSTRACT FROM AUTHOR]

The spatial structure of populations is key to many (eco-)evolutionary processes. In such cases, the strength and sign of selection on a trait may depend on the spatial scale considered. An example is the evolution of altruism: selection in local environments often favours cheaters over altruists, but this can be outweighed by selection at larger scales, favouring clusters of altruists over clusters of cheaters. For populations subdivided into distinct groups, this effect is described formally by multilevel selection theory. However, many populations do not consist of non-overlapping groups but rather (self-)organize into other ecological patterns. We therefore present a mathematical framework for multiscale selection. This framework decomposes natural selection into two parts: local selection, acting within environments of a certain size, and interlocal selection, acting among them. Varying the size of the local environments subsequently allows one to measure the contribution to selection of each spatial scale. To illustrate the use of this framework, we apply it to models of the evolution of altruism and pathogen transmissibility. The analysis identifies how and to what extent ecological processes at different spatial scales contribute to selection and compete, thus providing a rigorous underpinning to eco-evolutionary intuitions. [ABSTRACT FROM AUTHOR]

Forecasting trends in sustainable sustainability levels in metropolitan areas serves as the foundation for developing development policies that are tailored to local conditions. Sustainability evaluation studies based on a multidimensional comprehensive index system fall short of highlighting the variability, systemic, and dynamic nature of metropolitan area development. To better understand the role of multidimensional scenarios in guiding the sustainable development of metropolitan areas, a greater emphasis on suburban spatial units and spatial heterogeneity characteristics is required. Methods: We simulate the trends of sustainable development levels of 16 municipal districts in Beijing, China from 2011 to 2030 by combining the system dynamics model and the shared socioeconomic pathways, and thus condense the metropolitan area's sustainable development model and compare the advantages and shortcomings of each development scenario under different models. Results: The findings show that: (1) Beijing's municipal districts perform differently in economic, social, and environmental subsystems, and there are three types of typical districts: Synergistic development, ecologically biased development, and economic constraint. (2) Shared socioeconomic pathway (SSP) 1 is the most desirable urban sustainable development scenario among the four scenarios of SSP1, SSP2 (BAU (business-as-usual)), SSP3, and SSP5. (3) In order to achieve the transition from the historical trajectory to the SSP1 scenario, each district type should pursue a distinct development strategy. To improve the quality of coordinated development, synergistic development type zones should use social security and employment expenditures to compensate for the shortcomings of social development. Ecologically biased zones should reduce energy consumption and increase environmental protection investment to maintain environmental advantages, and economic constraint type zones can maintain high gross domestic product growth rates in the short term to get out of the development dilemma. Conclusions: The findings of this paper highlight the complex cause-and-effect relationships between urban economic, social, and environmental systems and offer a framework for system evaluation and simulation technology for the sustainable development of metropolitan areas. This framework will serve as a source of regulations and a foundation for management of urban refinement. [ABSTRACT FROM AUTHOR]

Recent developments within the IUCN and the Convention on Biological Diversity have affirmed the increasingly key role that effective population size (Ne) and the effective size: census size ratio (Ne/N) play in applied conservation and management of global biodiversity. This paper reviews and synthesizes information regarding the definition of Ne and demographic and genetic methods for estimating effective size, census size, and their ratio. Emphasis is on single‐generation estimates of contemporary Ne/N, which are the most informative for practical applications. It is crucial to clearly define which individuals are included in the census size (N). Defining N as the number of adults alive at a given time facilitates comparisons across species. For a wide range of applications and experimental designs, inbreeding Ne is simpler to calculate and interpret than variance Ne. Effects of skewed sex ratio are generally modest, so most reductions to Ne/N arise from overdispersed (greater‐than‐Poisson) variance in offspring number (σk2$$ {\sigma}_k^2 $$). Even when fecundity changes with age, overdispersed within‐age variance generally contributes most to overall σk2$$ {\sigma}_k^2 $$, and both random and deterministic (mediated by selection) factors can be important. Most species are age‐structured, so it is important to distinguish between effective size per generation (Ne) and the effective number of breeders in one season or year (Nb). Both Ne and Nb are important for applied conservation and management. For iteroparous species, a key metric is variance in lifetime reproductive success (σk•2$$ {\sigma}_{k\bullet}^2 $$), which can be affected by a variety of additional factors, including variation in longevity, skip or intermittent breeding, and persistent individual differences in reproductive success. Additional factors that can be important for some species are also discussed, including mating systems, population structure, sex reversal, reproductive compensation, captive propagation, and delayed maturity. [ABSTRACT FROM AUTHOR]

To analyze the community characteristics of tropical monsoon forests with different succession stages, four different plant communities named A, B, C, and D were investigated in this study, respectively, in a typical monsoon forest of Ehuangzhang in Yangchun, Guangdong Province. The species composition, biodiversity and spatial structure were analyzed, their maturity levels' differences were detemined, succession direction was predicted, and suggestions for optimization were put forward. The results were as follows: (1) The forest layers of the four communities were single. Small diameter at breast height (DBH) class trees and lower forest dominated these communities, owning 1-3 obvious dominant species. (2) The Shannon-Wiener index ranged from 2.72 to 3.74, Simpson index from 0.90 to 0.97, and Pielou evenness index from 0.74 to 0.89, suggesting that their diversity characteristics were significant differences. (3) Their dominance ranged from 0.49 to 0.51, uniform angle from 0.56 to 0.61, mingling from 0.54 to 0.83, forest spatial structure index from 60.57 to 71.44, forest spatial structure distance from 53.15 to 68.53. (4) The analysis of community basic characteristics, diversity characteristics and spatial structural characteristics indicated that the maturity levels in all community ranked D > A > C > B. In conclusion, four communities are currently in the pre- or mid-term succession stages and the development space of DBH and tree height is large. The four communities are in the moderate growth state. All trees show a slight aggregated distribution, and the tree species are moderately, strongly or very strongly mingling. Besides, there is a distance in spatial structure between four communities and ideal forest with the development of maturity levels. The four communities continue to succession with intolerant tree species as the main dominant tree species, and gradually and preliminarily have the typical vegetation characteristics of the district forest climax community. With the development of maturity levels, the four communities' biodiversity and mingling will increase, the spatial structure will be optimized and the stability will be enhanced. The results of this study provide scientific basis for community construction mechanism and forest structure optimization. In the future, Ehuangzhang tropical monsoon forests should be more regulated and protected, while the ecology of vegetation and biodiversity conservation in the area should be widely monitored and studied in depth. [ABSTRACT FROM AUTHOR]

Studies have shown that the springtime Arctic Oscillation (AO) has a strong influence on the subsequent Indian Ocean Dipole (IOD) and El Niño-Southern Oscillation (ENSO). Nevertheless, not every AO is followed by IOD and ENSO. This study divides the spring AO into three types: followed by both IOD and ENSO (AO-Both), followed by ENSO only (AO-ENSO), and followed by IOD only (AO-IOD). In the AO-Both type, the Pacific component of the AO, which is characterized by a dipole pattern, induces sea surface temperature (SST) anomalies in the subtropical North Pacific that extend southward to the tropical Pacific via a wind-evaporation-SST (WES) feedback. The generated tropical SST anomalies influence subsequent ENSO via tropical air-sea interaction and impact autumn IOD via modulation of the tropical Walker circulation. In the AO-ENSO type, the Pacific component of the AO is featured by a mono-pole anomaly pattern with a center over the mid-latitude northeast Pacific. The northeast Pacific atmospheric anomalies propagate southward and lead to surface zonal wind anomalies in the tropical central Pacific via the WES feedback that influence subsequent ENSO via tropical air-sea interaction. In the AO-IOD type, the Pacific component of the AO is weak. Spring AO-related atmospheric heating anomalies over the North Atlantic excite a wave train extending from the North Atlantic to the western Pacific. The associated low-level wind anomalies induce SST anomalies around the Maritime Continent, which play a crucial role in influencing subsequent IOD. This study suggests that the spatial pattern of the AO plays a critical role in determining its impact on tropical climate variability. [ABSTRACT FROM AUTHOR]

In order to optimize the spatial pattern of mountainous settlements and reasonably plan national land space, and further promote the process of rural revitalization, the spatial structure characteristics of mountainous settlements were regarded as one of the important research objects. The mountainous settlements in the upper reaches of the Min River were taken as the research object. Based on the principle of urban order scale, aggregation dimension and correlation dimension methods, the spatial structure characteristics of administrative and geometric centers of settlements in the upper reaches of the Min River were analyzed and compared, and the reasons for the errors were summarized. Results show that the structural characteristics of the first distributed urban system in the upper reaches of the Min River are obvious. the cumulative percentage curve of the county population is consistent with the characteristics of rank-scale. The fractal characteristics of the spatial structure of settlements in the upper reaches of the Min River are significant. Due to the significant influence of the economy, settlements gather and distribute in space, gradually decreasing towards the surrounding areas centered around the top cities and towns. The correlation dimension and the ratio of cattle to crows in the upper reaches of the Min River reveal the characteristics of urban interaction intensity and traffic accessibility, which are consistent with the actual situation. The error caused by the administrative center is closely related to the average altitude of the research area, and its deviation from the geometric center is relatively large in areas with high average altitude. The impact of its deviation on the research results should be taken seriously. [ABSTRACT FROM AUTHOR]

Forest management relies on forest spatial structure, but studies on the spatial structure of Vietnamese forests are limited. Therefore, two one–hectare plots were established in tropical rainforest in Tuyen Quang province to evaluate the characteristics and spatial structures of plant communities. Descriptive statistics and species importance value indices were calculated for each plot. Then, to assess differences between plots, detrended correspondence analysis was applied. Species mingling, uniform angle, diameter dominance and carbon stock dominance indices were also computed to analyze forest spatial structures. The results indicated that 65–70% of trees occurred in areas with high diversity, and 55–58% of trees were randomly distributed. The number of dominant and non–dominant individuals, in terms of diameter and carbon stock, was similar at the stand level. In all estimated patterns, units with high species mixtures predominated. As biodiversity increased, the distribution of forest trees became more random. The quadrivariate distribution illustrated considerable differences between plots, the study area and other regions. Findings from multivariate distributions provide accurate information in each group of spatial indices and these can be used to select appropriate silvicultural measures for stand management. [ABSTRACT FROM AUTHOR]

Population monitoring of Atlantic salmon (Salmo salar L.) abundance is an essential element to understand annual stock variability and inform fisheries management processes. Smolts are the life stage marking the transition from the freshwater to the marine phase of anadromous Atlantic salmon. Estimating smolt abundance allows for subsequent inferences on freshwater and marine survival rates. Annual abundances of out‐migrating Atlantic salmon smolts were estimated using Bayesian models and an 18‐year capture–mark–recapture time series from two to five trapping locations within the Restigouche River (Canada) catchment. Some of the trapping locations were at the outlet of large upstream tributaries, and these sampled a portion of the total out‐migrating population of smolts for the watershed, whereas others were located just above the head of tide of the Restigouche River and sampled the entire run of salmon smolts. Due to logistic and environmental conditions, not all trapping locations were operational each year. Additionally, recapture rates were relatively low (<5%), and the absolute number of recaptures was relatively few (most often a few dozen), leading to incoherent and highly uncertain estimates of tributary‐specific and whole catchment abundance estimates when the data were modeled independently among trapping locations and years. Several models of increasing complexity were tested using simulated data, and the best‐performing model in terms of bias and precision incorporated a hierarchical structure among years on the catchability parameters and included an explicit spatial structure to account for the annual variations in the number of sampled locations within the watershed. When the best model was applied to the Restigouche River catchment dataset, the annual smolt abundance estimates varied from 250,000 to 1 million smolts, and the subbasin estimates of abundance were consistent with the spatial structure of the monitoring programme. Ultimately, increasing the probabilities of capture and the absolute number of recaptures at the different traps will be required to improve the precision and reduce the bias of the estimates of smolt abundance for the entire basin and within subbasins of the watershed. The model and approach provide a significant improvement in the models used to date based on independent estimates of abundance by trapping location and year. Total abundance and relative production in discrete spawning, nesting, or rearing areas provide critical information to appropriately understand and manage the threats to species that can occur at subpopulation spatial scales. [ABSTRACT FROM AUTHOR]

Based on big data for rail passenger transportation, this paper explores the spatial linkages among three major urban agglomerations of the Yangtze River Economic Belt, Including the Yangtze River Delta,the Middle Reaches of the Yangtze River City Agglomeration and the Chengdu-Chongqing City Agglomeration, as well as their spatial structural heterogeneity, from the intra- and extra-group perspectives. The results show that: ① The three major city ag‐ glomerations have stronger in-group links than out-group. There are predominantly intra-provincial links in both the Yangtze River Delta and the Middle Reaches of the Yangtze River City Agglomeration. The Chengdu-Chongqing city agglomeration has stronger inter-provincial links than intra-provincial links. However, the intensity of inter-provincial links within the three city agglomerations is much higher than that outside the agglomerations, implying that under the ef‐ fect of the mechanism of internal agglomeration, cities within the city agglomerations are more likely to break through the provincial boundaries to create links and realize the integrated development of the region. ② The intensity of intra-cluster and extra-cluster linkages of large city clusters reaches its highest at inter-city distances of 0-100 km and 0-300 km, respectively. And the intensity of in-group and out-group links between cities in the Yangtze River Delta and the Middle Reaches of the Yangtze River city agglomerations follow the law of distance decay, but in the Chengdu-Chongqing city agglomeration, only the out-group linkage conforms to this law. ③ Megacities dominate the in-group and out-group links of the three major urban agglomerations. In the in-group and out-group links, the urban connection intensity of the three major urban agglomerations at the same level is proportional to the city size, while the cross-level urban connection intensity is inversely proportional to the series difference. ④ The spatial structures of the Yangtze River Delta and the Middle Reaches of the Yangtze River City Agglomeration are polycentric, though the extra-cluster linkages have a reinforcing effect on the polycentric structure of the former. The Chengdu-Chongqing City Agglomeration has a "single-core" form in the view of intra-group linkage, and a "double-core" structure in the view of extra-group linkage and total linkage, indicating that the extra-group linkage is pushing the Chengdu-Chongqing City Agglomeration to change from a "single-center" to a "double-center" structure. [ABSTRACT FROM AUTHOR]

This paper aims to identify the spatial structure of Manado municipal, capital of North Sulawesi Province in Indonesia, through its density profile as indicator, which is the trend of density level according to the spatial units distance to the city center. This paper also tries to elaborate on the potential problems in the city as well as the urban planning policy which are associated with the spatial structure identified. The data used are the maps of administrative and built-up area and the distribution of population and service center by spatial units in Manado. The parameters of density profile examined are the administrative and built up density and the accessibility distance to the city center from the service center of the spatial units. By interpreting the existing density profile based on some relevant theoretical premises, the spatial structure type and its associative problems and policy can be identified. The result shows that the spatial structure of Manado municipal tends to be monocentric in certain boundary from the city center, but start shifting to polycentric pattern in the peri-urban zone. This characteristic is associated with some potential problems such as acute traffic congestion, air pollution, emerging of slum and squatter and the increased risk of disasters, specifically on downtown area. In the peri-urban zone, the potential significant problems is the phenomenon of sprawling and all its associated impacts such as fragmentation of green open space, increased dependence on private vehicles and increased investment and maintenance costs for infrastructure. [ABSTRACT FROM AUTHOR]

Deep neural networks are highly vulnerable to adversarial samples. Most existing adversarial defense methods do not consider the distribution of adversarial samples. We argue that very few adversarial samples in the natural sample set prevent the deep neural networks from learning a complete and effective representation of the adversarial samples. This causes the spatial structures between the natural and the adversarial samples to be vastly different from that of the input space, thus making the models vulnerable to adversarial attacks. Based on this viewpoint, this paper proposes an effective deep-learning adversarial defense method, which incorporates information about the spatial structures of the natural and the adversarial samples in the embedding space during the training process. This proposed approach improves the deep learning model's generalization to new adversarial samples and achieves the purpose of defending against adversarial attacks. Four deep neural networks with different scales are used and experimentally verified on four typical publicly available image data. The experimental results show that our method effectively improves the defense ability of deep learning models against adversarial attacks. • Development of an effective adversarial training method using spatial structure constraints in embedding space. • Spatial structure information of the natural and adversarial samples can help improve the adversarial robustness of DNNs. • The spatial structure constrain can be extended to adversarial training of semi-supervised and unsupervised learning. [ABSTRACT FROM AUTHOR]

To explore the interaction between the spatial structure of different types of natural forest stands and the diversity of woody plants. The fixed monitoring sample plots of Pinus massoniana, Cunninghamia lanceolata, and Fagus lucida three types natural forests were established in the Xingdoushan Nature Reserve, in accordance with the CTFS plot standards. The differences in spatial structure and woody plant diversity among different types of forests were analyzed through sample plots investigation. The impact of forest spatial structure indicators on woody plant diversity was tested by Pearson correlation analysis. The results showed that:there is no significant difference of the three stands mingling and uniform angle index. There is a certain difference in the dominance of size differentiation between the forests of Cunninghamia lanceolata and Fagus lucida, but all three stands form a mixed, clustered, and competitive growth state. The species composition of woody plants in various stands is rich. The Shannon Weiner index, Simpson index and species number of the tree layer in the Cunninghamia lanceolata forest are the highest, but there is no significant difference between the three types of natural forests(P>0.05), and the Pielou index value in the Fagus lucida forest is the highest, and there was no significant difference(P>0.05) among different forest types. The Shannon Weiner index and Simpson index values of the shrub layer in the natural forest of Pinus massoniana are the highest, and the Shannon Weiner index of the shrub layer in the forest of Fagus lucida is significantly lower than the forest of Pinus massoniana(P<0.05). The Simpson index value is also significantly lower than the forest of Pinus massoniana and Cunninghamia lanceolata(P<0.05), but Pielou index of the Fagus lucida forest is significantly higher than that in the other two stands(P<0.05), and the number of species is significantly higher than the forest of Cunninghamia lanceolata(P<0.05). There are certain differences in the impact of spatial structure indicators on the diversity of woody plants in different forest, mingling is the dominant influencing factor, and the stronger the mingling, the higher the species diversity. It is recommended to appropriately supplement certain artificial intervention measures to improve the forest structure, enhance biodiversity, and fully utilize the forest value and various ecological service functions. [ABSTRACT FROM AUTHOR]

Investigating eco‐evolutionary responses of populations to environmental changes requires a solid understanding of the spatial context in which they evolve. While the interplay between local adaptation and dispersal in guiding evolutionary outcomes has been studied extensively, it is often in a context of divergent selection and simplified spatial structure. Alternatively, we used a spatially‐explicit demo‐genetic agent‐based model to simulate a complex network of interconnected populations of Atlantic salmon facing a perturbation shifting their genetic composition to create diversity among populations. Our model allowed us to track emerging demographic, phenotypic, and evolutionary changes from the individual to the metapopulation in a single, spatially realistic framework. We analyzed the influence of the spatial structure of genetic diversity and populations on the evolutionary dynamics under convergent selection (toward a common optimum). Our simulations showed adaptation and demographic recovery of local populations was enhanced by dispersal between initially diverse populations, providing general support for the adaptation network theory. This was particularly true for increased dispersal rates and a random spatial genetic structure. Importantly, our spatially realistic model emphasized that the evolutionary and demographic trajectories of local populations are context‐dependent and can be heavily influenced by the spatial configuration of populations linked by dispersal. Overall, the adaptive capacity of the network depended on the 'opportunity for adaptation' provided by immigration patterns that emerged from the connectivity structures of the scenarios tested. We highlight the importance of spatial diversity and population structure for the ability of species to respond to environmental change, with implications for management and conservation of spatially structured populations. [ABSTRACT FROM AUTHOR]

Data on the breeding performance and territorial behavior of two common tundra skuas were collected in the years 1996–2000 (with some lacunae) in the vicinities of Medusa Bay (73°21′ N, 80°32′ E), northwestern Taimyr Peninsula. The spatial distribution of nests or centers of breeding territories in both skua species appears to be grouped (clustered). This means that the spatial population structure of skuas, especially long-tailed ones, mostly consists of permanent breeding sites, or territorial cells. Such reusable territorial cells in pomarine skuas are more prominent than in long-tailed skuas. The features of the breeding habitat seem to be not so important to the latter species than to the former one. The reasons for such an attraction to certain sites in the tundra that omit to differ from many others are not yet clear. "Signal field" theory cannot account for this attraction. In fact the basis of dividing the breeding area into permanent territorial cells and of choosing definite ones among them seems to indicate that birds are oriented to certain still-unknown features of the environment rather than solely to the ecological characteristics of the habitat and/or to tracks from previous activity of birds. Long-tailed skuas in their choice of breeding sites prefer territorial cells where the influence of human presence is relatively strong. The same was not noticed for pomarine skuas. This might be because the latter are stronger birds capable of resisting Arctic foxes and thus needing no additional factor of protection like the presence of humans. [ABSTRACT FROM AUTHOR]

Plant spatial distribution is an important topic in ecology as it determines species coexistence and biodiversity dynamics. Usually, plants show clustered distributions in nature. Mistletoes are a good example of aggregated distributions, as they form dense aggregations due to several factors (availability of competent hosts, seed dispersal vectors, microclimate conditions).We analysed four native mistletoe species with divergent life histories and host ranges: Desmaria mutabilis and Tristerix corymbosus from the temperate rainforests of southern Chile; and Tristerix aphyllus and Tristerix verticillatus from the northern semi‐desert zone. While T. corymbosus and T. verticillatus have a wide host range, T. aphyllus and D. mutabilis are specialists that can parasitize only a few plant species. We hypothesized that specialized species would be more aggregated due to ecological and environmental restrictions. We used heterogeneous Poisson models to quantify spatial aggregation.Three of the four mistletoe species were spatially clustered at both environments, with aggregation being stronger in the temperate rainforest of southern Chile and particularly in the host‐specialist species. Our results suggest that environmental constraints are more important than ecological constraints (host range) in shaping mistletoe spatial structure.Mistletoe aggregated spatial distribution depends primarily on the environment that they inhabit, which conditions host spatial availability, and arrangement. [ABSTRACT FROM AUTHOR]

Regulating site‐to‐site interactions between active sites can effectively tailor the electrocatalytic behavior of single‐atom catalysts (SACs). The conventional SACs suffer from low density of single atoms and lack of site‐to‐site interactions between them. Herein, a series of interactive Pt SACs with controllable Pt–Pt spatial correlation degree and local coordination environment is developed by integrating densely populated Pt single atoms in the sub‐lattice of a Co3O4 matrix. The obtained interactive Pt‐Co3O4 catalysts demonstrate remarkable electrocatalytic performance toward hydrogen production, outperforming those of isolated single atom‐ and nanoparticle‐based catalysts. The intrinsic catalytic activity of interactive Pt‐Co3O4 catalysts is closely dependent on the spatial structure of Pt sites with the adjusted d‐band center by regulating contents and atomic configuration of Pt sites. This work provides fundamental insights for the structure‐property relationship on interactive single active sites, which is expected to direct the rational design of highly efficient SACs. [ABSTRACT FROM AUTHOR]

Objective In order to improve the yield of tert-butylphenyl diphenyl phosphate(BPDP) synthesized by one-pot method, alkyl imidazole hydrogen sulfate ionic liquids with different spatial structures and electronic groups were used as catalysts. Methods This study compared the effects of N-alkyl imidazole hydrogen sulfate ionic liquids with different carbon chains and alkyl imidazole hydrogen sulfate ionic liquids with different electronic groups on the yield of BPDP synthesis, and further investigated the effects of catalyst dosage and catalyst circulation on the yield. Results When the side chain structure of the catalyst is ethyl, the yield of BPDP is the highest. Electron-absorbing groups can increase the yield of BPDP, while electron-donating groups can reduce the yield of BPDP. The yield of BPDP is the highest when the catalyst dosage is 1.5 w% of 4-tert butylphenol. The catalyst still has high catalytic activity after 6 cycles of useage. Conclusions The spatial structure and electronic groups of ionic liquid catalysts have a significant effect on the yield of BPDP. When 1-ethyl-2-fluoro-imidazole hydrogen sulfate ionic liquid is used as the catalyst, the yield of BPDP can increase to 85.3 w%, thereby economic benefits can be improved. [ABSTRACT FROM AUTHOR]

We focus on the extent to which polycentric urban regions can substitute for the agglomeration economies provided by large cities. Building on an open‐source software tool that helps identifying polycentric developments in urban regions, we analyse the spatial structure (in terms of size, dispersion and polycentricity) of 94 regions across 34 European countries and link this to their level of total factor productivity. We find that both more polycentric regions and more dispersed regions are associated with lower productivity levels. [ABSTRACT FROM AUTHOR]

Reproductive mode may strongly impact adaptation in spatially varying populations linked by dispersal, especially when sexual and clonal offspring differ in dispersal. We determined how spatial structure affects adaptation in populations with mixed clonal and sexual reproduction. In a source-sink quantitative genetic deterministic model (with stabilizing selection around different optima), greater clonal reproduction or parent-offspring association (a measure of the part of the parent's phenotype other than the additive genetic component inherited by clonal offspring) increased the selective difference (difference between phenotypic optima) allowing sink populations to adapt. Given dispersal differences between clonally and sexually produced juveniles, adaptation increased with an increasing fraction of clonal dispersers. When considering migrational meltdown, partially clonal reproduction reduced cases where dispersal caused habitat loss. Stochastic individual-based simulations support these results, although the effect of differential dispersal was reversed, with decreased clonal dispersal allowing greater adaptation. These results parallel earlier findings that for an instantaneous shift in phenotypic optimum, increasing clonality allowed population persistence for a greater shift; here, selective change is spatial rather than temporal. These results may help explain the success of many partially clonal organisms in invading new habitats, complementing traditional explanations based on avoiding Allee effects. [ABSTRACT FROM AUTHOR]

Urban spatial elements present agglomeration and dispersion geographic processes in the urban development. Identifying the characteristics of their distribution changes and accurately capturing the evolution of the urban spatial structure is of great significance to urban construction and management. This study takes Wuhan as a case study and focuses on the spatial agglomeration distribution of urban elements. Point of Interest (POI) data from 2017 to 2021 were collected, and the Block2Vec model was employed to extract the comprehensive geographic information from various elements within the traffic analysis zones (TAZs). Subsequently, identification and division were carried out to access the level of urban spatial element agglomeration. Finally, the spatial–temporal evolution characteristics of urban aggregated elements in the Wuhan metropolitan development area over five years were compared and analyzed. The results indicate the following: (1) urban elements present an obvious circle structure in their spatial agglomeration, with distinct differences observed among different element types; (2) from 2017 to 2021, the Wuhan urban development zone experienced obvious expansion in urban space; (3) increased agglomeration of spatial elements mainly occurred in the surrounding areas of the city, while some areas in the city center displayed weaker element agglomeration and a reduction in various service facilities. The results demonstrate that the method used in this study could effectively identify the spatial agglomeration distribution of urban elements, as well as accurately distinguishing regions with distinct development characteristics. This approach could provide robust support for optimizing land use and urban spatial planning. [ABSTRACT FROM AUTHOR]

Despite the well known scale‐dependency of ecological interactions, relatively little attention has been paid to understanding the dynamic interplay between various spatial scales. This is especially notable in metacommunity theory, where births and deaths dominate dynamics within patches (the local scale), and dispersal and environmental stochasticity dominate dynamics between patches (the regional scale). By considering the interplay of local and regional scales in metacommunities, the fundamental processes of community ecology—selection, drift, and dispersal—can be unified into a single theoretical framework. Here, we analyze three related spatial models that build on the classic two‐species Lotka–Volterra competition model. Two open‐system models focus on a single patch coupled to a larger fixed landscape by dispersal. The first is deterministic, while the second adds demographic stochasticity to allow ecological drift. Finally, the third model is a true metacommunity model with dispersal between a large number of local patches, which allows feedback between local and regional scales and captures the well studied metacommunity paradigms as special cases. Unlike previous simulation models, our metacommunity model allows the numerical calculation of equilibria and invasion criteria to precisely determine the outcome of competition at the regional scale. We show that both dispersal and stochasticity can lead to regional outcomes that are different than predicted by the classic Lotka–Volterra competition model. Regional exclusion can occur when the nonspatial model predicts coexistence or founder control, due to ecological drift or asymmetric stochastic switching between basins of attraction, respectively. Regional coexistence can result from local coexistence mechanisms or through competition‐colonization or successional‐niche trade‐offs. Larger dispersal rates are typically competitively advantageous, except in the case of local founder control, which can favor intermediate dispersal rates. Broadly, our models demonstrate the importance of feedback between local and regional scales in competitive metacommunities and provide a unifying framework for understanding how selection, drift, and dispersal jointly shape ecological communities. [ABSTRACT FROM AUTHOR]

The article explores the concept of "sociovirology" and its application in studying the evolution of virus life-history traits. It emphasizes the social nature of viruses and the importance of understanding their interactions with hosts. The article discusses the challenges of measuring virus fitness in a social context and the role of relatedness in shaping selective pressures on virus populations. It also suggests that evolutionary epidemiology and multiple infection theory can provide useful frameworks for studying virus evolution. The article raises questions about the appropriateness of the term "sociovirology" and highlights the need for a formal definition of fitness in this context. [Extracted from the article]

Gut dysbiosis causes damage to the intestinal barrier and is associated with type 2 diabetes mellitus (T2DM). We tested the potential protective effects of probiotic BL21 and LRa05 on gut microbiota in type 2 diabetes mellitus mice and determined whether these effects were related to the modulation of gut microbiota.Thirty specific pathogen-free C57BL/6J mice were randomly allocated to three groups—the (CTL) control group, HFD/STZ model (T2DM) group, and HFD/STZ-probiotic intervention (PRO) group—and intragastrically administered strains BL21 and LRa05 for 11 weeks. The administration of strains BL21 and LRa05 significantly regulated blood glucose levels, accompanied by ameliorated oxidative stress in mice. The BL21/LRa05-treated mice were protected from liver, cecal, and colon damage. Microbiota analysis showed that the cecal and fecal microbiota of the mice presented significantly different spatial distributions from one another. Principal coordinate analysis results indicated that both T2DM and the BL21/LRa05 intervention had significant effects on the cecal contents and fecal microbiota structure. In terms of the fecal microbiota, an abundance of Akkermansia and Anaeroplasma was noted in the PRO group. In terms of the cecal content microbiota, enrichment of Akkermansia, Desulfovibrio, Bifidobacterium, Lactobacillus, and Limosilactobacillus was noted in the PRO group. The probiotics BL21 and LRa05 prevent or ameliorate T2DM by regulating the intestinal flora and reducing inflammation and oxidative stress. Our results suggest that BL21 and LRa05 colonize in the cecum. Thus, BL21/LRa05 combined with probiotics having a strong ability to colonize in the colon may achieve better therapeutic effects in T2DM. Our study illustrated the feasibility and benefits of the combined use of probiotics and implied the importance of intervening at multiple intestinal sites in T2DM mice. [ABSTRACT FROM AUTHOR]

Lumpfish, Cyclopterus lumpus, have historically been harvested throughout Atlantic Canada and are increasingly in demand as a solution to controlling sea lice in Atlantic salmon farms—a process which involves both the domestication and the transfer of lumpfish between geographic regions. At present, little is known regarding population structure and diversity of wild lumpfish in Atlantic Canada, limiting attempts to assess the potential impacts of escaped lumpfish individuals from salmon pens on currently at‐risk wild populations. Here, we characterize the spatial population structure and genomic‐environmental associations of wild populations of lumpfish throughout the Northwest Atlantic using both 70K SNP array data and whole‐genome re‐sequencing data (WGS). At broad spatial scales, our results reveal a large environmentally associated genetic break between the southern populations (Gulf of Maine and Bay of Fundy) and northern populations (Newfoundland and the Gulf of St. Lawrence), linked to variation in ocean temperature and ice cover. At finer spatial scales, evidence of population structure was also evident in a distinct coastal group in Newfoundland and significant isolation by distance across the northern region. Both evidence of consistent environmental associations and elevated genome‐wide variation in FST values among these three regional groups supports their biological relevance. This study represents the first extensive description of population structure of lumpfish in Atlantic Canada, revealing evidence of broad and fine geographic scale environmentally associated genomic diversity. Our results will facilitate the commercial use of lumpfish as a cleaner fish in Atlantic salmon aquaculture, the identification of lumpfish escapees, and the delineation of conservation units of this at‐risk species throughout Atlantic Canada. [ABSTRACT FROM AUTHOR]

The strategic position of the Beibu Gulf urban agglomeration has become increasingly prominent in terms of national economic development. In this paper, we propose the life cycle theory of urban agglomerations from the perspective of tourism-economic linkages and study the evolution of tourism-economic linkages and the spatial structure of emerging urban agglomerations in the Beibu Gulf using a modified gravity model and social network analysis. The results show the following: 1) The tourism-economic connection of the Beibu Gulf urban agglomeration was initially limited to neighboring cities dominated by provincial capital cities. Nanning is the main location for developing the tourism economy. With improvements in traffic and the implementation of national policies, tourism-economic ties among urban agglomerations have gradually deepened, with the total number of these connections increasing from 174.84 to 6, 542.94 in 2019. The total number of connections in 2019 was 37.42 times that of 2011. The tourism-economic connection structure developed from a loose to a multicore network structure. 2) The density of the tourism-economic connection network in the Beibu Gulf urban agglomeration increased by 6.01 times. The network structure changed from loosely to relatively closely connected, and the degree of tourism economic connections has continuously improved. Moreover, the scope of the core area of the tourism economy continues to expand. The internal network density of the core area increased to 0.833 in 2019, and the links between the core areas continue to strengthen. Although the network density in the fringe area has increased, the internal tourism-economic connection remains weak. 3) The spatial structure of the Beibu Gulf urban agglomeration has evolved from a single center in Nanning to a network-type spatial structure of three centers, seven nodes, and five edges. Nanning, Zhanjiang, and Haikou are important tourism centers and growth poles. The centrality of urban agglomerations has changed from severe polarization and disparity in development status between cities to a more balanced development trend. Among the cities under the jurisdiction of Hainan, except for Haikou, the development of the tourism economy is relatively slow. 4) The Beibu Gulf urban agglomeration entered its growth stage after its embryonic development. However, its development still faces three obstacles: administrative barriers, low competitiveness of tourism products, and unobstructed tourism flow, and it remains far from becoming a mature urban agglomeration. This paper proposes an optimized development mechanism for the Beibu Gulf urban agglomeration of government promotion, transportation linkage, and industrial interaction that is conducive to the high-quality development of the Beibu Gulf urban agglomeration. In conclusion, the main content of this study can compensate for the lack of research on the spatial structure of tourism-economic linkages in emerging urban agglomerations to a certain extent and provide a reference for the development of urban agglomerations in the embryonic and growth stages. [ABSTRACT FROM AUTHOR]

The inefficient use of urban resources and the imbalance of spatial structures make optimizing land use management a top priority in urban environmental management. Traditional land use classification systems that prioritize only natural features while disregarding human activity can result in redundancy and conflicts in urban planning. The Production–Living–Ecological Space (PLES) approach was developed as an integrated method for territorial spatial classification. However, most existing studies on PLES are conducted at provincial scales, largely overlooking fine-scale usage within cities. In addition, the existing concept of PLES has been vaguely defined, resulting in linear and simple identification methods that are not applicable to complex urban environments. To address these issues, this study proposes a method to identify urban PLES based on supervised classification using random forest models, which integrate empirical knowledge and multi-source heterogeneous information. The experiments conducted in Haikou reveal the regional aggregation of living and production spaces and the scarcity of ecological space in the city. Our study proposes a concrete concept of PLES and a method for identifying PLES that can be applied to multiple regions, providing an effective tool for the coordinated management of urban production, living, and ecological environments. [ABSTRACT FROM AUTHOR]

The historical experience of urbanization and urban agglomeration development shows that the new urbanization strategy of “relying on urban agglomeration” is the inevitable choice to realize Chinese modernization. The connotation of Chinese modernization also puts forward new requirements for high-quality urbanization. Starting from the “urbanization of people” and moving towards the new journey of building a modern country, we must meet the development demand and stage requirements of the spatial structure of urban agglomerations, construct the urban scale system scientifically with new development concepts, improve the spatial distribution of population, and set a new pattern of regional economic development. Based on the characteristics of Chinese modernization proposed at the 20th National Congress of CPC, this paper discusses the internal requirements of Chinese new urbanization, analyzes the existing problems of urban development so far, so as to explore the future development path. Accurately grasping the development pattern of urban agglomeration and urban in China, scientifically designing the scale system and improving the spatial distribution with new development concepts are conducive to the realization of a “human-centered” new type of urbanization. In this way, we will open up a new realm of Chinese-style modernization with the feature of populous development, common prosperity, harmony between material and spiritual civilization, harmonious coexistence between man and nature, and peaceful development. In the process of urbanization at the present stage, problems such as extensive urban sprawl, scale system imbalance, inferior spatial form and radical construction should be solved dynamically. That is, spatial layout should be optimized in the process of coordinated development, the allocation of resource should be optimized in the process of scale growth, and common prosperity should be realized in the process of urban and rural integration. Based on the spatial structure and scale system of urban agglomerations, it is necessary to sort out the formation mechanism of urban agglomerations in order to design the development path of Chinese-style high-quality urbanization. This includes the spatial differentiation mechanism of urban agglomeration size and function, the spatial characteristics and mechanism of monocentric and multicentric structures, the polarization and trickle action of the largest city, and the formation and optimization mechanism of urban spatial network. In order to explain the spatial dispersion of economic activities and the development model of polycentric cities, this paper calculates the spatial compactness and polycentric degree of 333 cities based on the geographic information system Arcgis 9.2, which shows that the reduction of compactness is the inevitable result of urban scale expansion and extensive sprawl. The multi-center development mode is the way to change the bad shape of city and achieve high quality development. From the perspective of new development pattern, Chinese new urbanization requires the optimization of spatial structure and hierarchical system of all cities, so as to form a functional layout of urban agglomeration with coordinated economic development, mutually complementary functions, reasonable division of labor in industries, and optimal spatial efficiency. Further promoting the new Chinese-style urban development model, improving the structure of city clusters and steadily raising the quality of urbanization will provide solid support for comprehensively building a modern socialist country. On this basis, this paper proposes to rely on urban agglomeration to integrate resources and give play to scale effect and trickle effect. Coordinate the division of labor of large, medium and small cities within the group to achieve a reasonable and efficient spatial structure of urban agglomeration. Besides, recommendations such as improving the management system and mechanism of urban agglomerations and coordinating the interests of all parties, promoting rural revitalization, focusing on the integrated development of urban and rural industries to achieve common prosperity are made in this paper. [ABSTRACT FROM AUTHOR]

This research paper delves into the important study field of predicting the cruise tourism market in the context of tourism science decision-making. The paper introduces the gravity model, which incorporates migration restrictions and cruise line correction factors to the supply-demand relationship of cruise tourism, to discover the spatial pattern and developmental law of China's cruise tourism market from 2011-2019. Utilizing the competitive state model, the paper proposes graded development strategies for the tourist markets of different cruise home ports. Research findings include: (1) China's domestic tourist source market presents regional differences primarily along the "Hu line", with significant eastward and near-domain oriented characteristics; (2) neighboring ports demonstrate homogeneity within their tourist source structures, such as the similarities in tourist market structure between Shanghai port and Wuhan port; (3) Sanya Port's cruise passenger source market highlights the significant specificity of long-distance tourists, contradicting the spatial distance attenuation law observed in the attraction of other ports. With the application of the gravity model, this study expands the depth of cruise tourism market research, providing a practical reference for passenger market development and postCOVID-19 cruise market recovery. [ABSTRACT FROM AUTHOR]

Migration is a major engine of demographic change for towns, regions, and whole countries. Traditionally, migrations have been divided into those caused by push or pull factors or classified by events that triggered them. In other words, push and pull factors are but one way to classify migration movements. This work distinguishes between life course and structural migrations. Life course migrations are linked to important events in people's lives such as graduation, marriage, having children, job promotions, discharge from the military, or retirement and the motivation comes from the migrant. Structural migrations are caused by changes in the economic, social, political, or natural environment and, therefore, externally motivated. This classification scheme is compatible with and complementary to existing classifications and particularly those based on push and pull factors. It yields some additional insights for policy making, empirical research, and migration modeling. [ABSTRACT FROM AUTHOR]

Lignin structure is an important factor affecting the cooking part of the pulping process. In this study, the effect of lignin side chain spatial configuration on cooking performance was analyzed, and the structural characteristics of eucalyptus and acacia during cooking were compared and studied by combining ozonation, GC-MS, NBO, and 2D NMR (1H-13C HSQC). In addition, the changes in the lignin content of four different raw materials during the cooking process were studied via ball milling and UV spectrum analysis. The results showed that the content of lignin in the raw material decreased continuously during the cooking process. Only in the late cooking stage, when the lignin removal reached its limit, did the lignin content tend to be stable due to the polycondensation reaction of lignin. At the same time, the E/T ratio and S/G ratio of the reaction residual lignin also followed a similar rule. At the beginning of cooking, the values of E/T and S/G decreased rapidly and then gradually rose when they reached a low point. The different initial E/T and S/G values of different raw materials lead to the disunity of cooking efficiency and the different transformation rules of different raw materials in the cooking process. Therefore, the pulping efficiency of different raw materials can be improved using different technological means. [ABSTRACT FROM AUTHOR]