Understanding the uneven spread of COVID-19 in the context of the global interconnected economy

The worldwide spread of the COVID-19 pandemic is a complex and multivariate process differentiated across countries, and geographical distance is acceptable as a critical determinant of the uneven spreading. Although social connectivity is a defining condition for virus transmission, the network paradigm in the study of the COVID-19 spatio-temporal spread has not been used accordingly. Toward contributing to this demand, this paper uses network analysis to develop a multidimensional methodological framework for understanding the uneven (cross-country) spread of COVID-19 in the context of the globally interconnected economy. The globally interconnected system of tourism mobility is modeled as a complex network and studied within the context of a three-dimensional (3D) conceptual model composed of network connectivity, economic openness, and spatial impedance variables. The analysis reveals two main stages in the temporal spread of COVID-19, defined by the cutting-point of the 44th day from Wuhan. The first describes the outbreak in Asia and North America, the second stage in Europe, South America, and Africa, while the outbreak in Oceania intermediates. The analysis also illustrates that the average node degree exponentially decays as a function of COVID-19 emergence time. This finding implies that the highly connected nodes, in the Global Tourism Network (GTN), are disproportionally earlier infected by the pandemic than the other nodes. Moreover, countries with the same network centrality as China are early infected on average by COVID-19. The paper also finds that network interconnectedness, economic openness, and transport integration are critical determinants in the early global spread of the pandemic, and it reveals that the spatio-temporal patterns of the worldwide spreading of COVID-19 are more a matter of network interconnectivity than of spatial proximity.

Single Cell Spatial Analysis Reveals the Topology of Immunomodulatory Purinergic Signaling in Glioblastoma

Glioblastoma develops an immunosuppressive microenvironment that fosters tumorigenesis and resistance to current therapeutic strategies. Here we use multiplexed tissue imaging and single-cell RNA-sequencing to characterize the composition, spatial organization, and clinical significance of extracellular purinergic signaling in glioblastoma. We show that glioblastoma exhibit strong expression of CD39 and CD73 ectoenzymes, correlating with increased adenosine levels. Microglia are the predominant source of CD39, while CD73 is principally expressed by tumor cells, particularly in tumors with amplification of EGFR and astrocyte-like differentiation. Spatially-resolved single-cell analyses demonstrate strong spatial correlation between tumor CD73 and microglial CD39, and that their spatial proximity is associated with poor clinical outcomes. Together, this data reveals that tumor CD73 expression correlates with tumor genotype, lineage differentiation, and functional states, and that core purine regulatory enzymes expressed by neoplastic and tumor-associated myeloid cells interact to promote a distinctive adenosine-rich signaling niche and immunosuppressive microenvironment potentially amenable to therapeutic targeting.

A multilayer network model of neuron-astrocyte populations in vitro reveals mGluR5 inhibition is protective following traumatic injury

Astrocytes communicate bidirectionally with neurons, enhancing synaptic plasticity and promoting the synchronization of neuronal microcircuits. Despite recent advances in understanding neuron-astrocyte signaling, little is known about astrocytic modulation of neuronal activity at the population level, particularly in disease or following injury. We used high-speed calcium imaging of mixed cortical cultures in vitro to determine how population activity changes after disruption of glutamatergic signaling and mechanical injury. We constructed a multilayer network model of neuron-astrocyte connectivity, which captured distinct topology and response behavior from single cell type networks. mGluR5 inhibition decreased neuronal, but did not on its own disrupt functional connectivity or network topology. In contrast, injury increased the strength, clustering, and efficiency of neuronal but not astrocytic networks, an effect that was not observed in networks pre-treated with mGluR5 inhibition. Comparison of spatial and functional community structure revealed that functional connectivity is largely independent of spatial proximity at the microscale, but mechanical injury increased the spatial-functional correlation. Finally, we found that astrocyte segments of the same cell often belong to separate functional communities based on neuronal connectivity, suggesting that astrocyte segments function as independent entities. Our findings demonstrate the utility of multilayer network models for characterizing the multiscale connectivity of two distinct but functionally dependent cell populations.

The Pazyryk Style

This study demonstrates that certain similarities in the domestic artifacts, clothing, and weapons in the Pazyryk burials of the Altai, those in the oases of Xinjiang (Subashi, Yanghai, Jumbulak Kum, Wupu, Keriya, etc.), and those in the piedmont of the southern Altai Mountains, do not evidence a single culture. Such parallels in basic items are caused only by spatial proximity and contacts. Personal ornaments, decoration of utensils, weapons, and horse harness, and signs such as tattoos are more reliable cultural indicators. Every member of the Pazyryk society, regardless of age, was marked by a set of outward signs, distinguishing him or her from the neighbors. This set included tattoos, and also ornaments worn on the clothing, headgear and belt, and decorating the horse. The elaborate Pazyryk traditions of woodcarving enabled everyone to have equally meaningful ornaments, which, like the artistic tattoos, made him or her recognizable. The term “Pazyryk style” is proposed. Being the most exact cultural indicator, it extends to all elements of culture, uniting the Pazyryk people despite the fact that their lifestyle, subsistence, etc., were identical to those of their neighbors.

Are family firms good neighbours? A spatial analysis of Italian technology-intensive firms

PurposeA burgeoning body of evidence points out the importance of spatial proximity in influencing firm efficiency besides internal characteristics. Nevertheless, the family status of the firm has been traditionally overlooked in that debate. Therefore, this study aims to investigate productivity spillovers stemming from the geographical closeness to innovators and family firms.Design/methodology/approachUsing secondary data on Italian technology-intensive manufacturing firms, the paper exploits spatial econometric models to estimate productivity spillovers across firms.FindingsAs regards the presence of spatial dependence, this study reveals that a firm's level of efficiency and productivity is influenced by that of nearby firms. Specifically, three main results emerge. First, spatial proximity to innovators is beneficial for the productivity of neighbouring firms. Second, closeness to family firms is a source of negative externalities for spatially proximate firms. However, and this is the third result, the adverse effect vanishes when the nearby family firms are also innovators.Research limitations/implicationsAs the study relies on cross-sectional data, future research should explore productivity spillovers in a longitudinal setting. Additionally, the channels through which productivity spillovers occur should be measured.Practical implicationsThe study highlights the importance of co-location for public policy initiatives to strengthen the competitiveness of firms and, indirectly, that of localities and regions. Moreover, the findings show the crucial role of innovation in mitigating the productivity gap between family and non-family firms.Social implicationsNotwithstanding the advent of the digital era, spatial proximity and localized social relationships are still a relevant factor affecting firms' performance.Originality/valueBy exploring the role of family firms in influencing the advantages of geographical proximity, this study contributes to the growing efforts to explore family enterprises across spatial settings.

Structure of the Erdenet ore district according to gravimetric data

The purpose of the study is construction of a model of the upper crust structure of the ore region in Mongolia and the three-dimensional mapping of intrusive bodies with which copper-porphyry mineralization is associated. An areal gravity survey was carried out with an observation density of 1 point per 6 km2 with the measurement accuracy of ±0.8 mGal. As a result, it was found that copper-molybdenum ore occurrences of the area including the Erdenet ore district are confined to local gravitational minima, which are interpreted as thickening of the body of the Selenga granitoids. The latter are confined to local depressions of this body base. The spatial proximity of supply channels of small ore-bearing intrusions and large granitoid bodies of the Selenga complex has been established. Porphyry ore intrusions are confined to rather wide (about 10 km) zones located above the depressions of the base of all intrusions of the Selenga complex (both granitoid and diorite). Since the local base depressions of the granitoid intrusions correspond to the position of magma supply channels, ore-bearing small intrusions were introduced approximately in the same places where the supply channels of granitoid intrusions of the Selenga complex existed. Therefore, it can be assumed that this case is characterized by not only tectonic inheritance (confined to the same faults and their intersection points), but also by a genetic one, since residual melts of the same foci, in which intrusion magma of the Selenga complex was generated might be the sources of small intrusions. From this point of view, the expediency of distinguishing an independent Erdenet complex seems to be controversial. Geophysical data on the spatial proximity of specified intrusion supply channels permit only to raise the question of such expediency. The solution to this issue is possible on the basis of a comprehensive analysis of petrological and geochemical data.

Proximity politics in changing oceans

How will ocean governance actors and institutions handle a future where the abundance and spatial distribution of marine life changes rapidly and variably? The answer, this paper argues, will be influenced by inherited and changing ocean proximity politics, whereby institutions and actors use spatial proximity or adjacency to legitimize particular forms of resource control, conservation and use. Focusing on United Nations and Canadian institutional contexts and recognizing state and non-state actors as agents of policy change, the paper documents and examines why and how spatial proximity has been invoked (i) as a principle for claiming, defining and implementing use rights, privileges and responsibilities for not just nation-states but also for other entities such as coastal communities and small-scale fisheries; (ii) to justify and legitimize rights, privileges and responsibilities for their interest and benefit; and (iii) to inform and challenge global and local discussions about principles such as conservation, sustainability and distributive equity. The future practical use of spatial closeness/distance for guiding policies of access and exclusion under conditions of change will likely be influenced by challenges associated with applying multiple and conflicting governance principles, accommodating diverse interests and interpretations of principle definition and application, and multiple forms of biophysical and social mobilities. The conclusion highlights four areas of further research and policy engagement for the study of ocean proximity politics.

Hitting Times of Some Critical Events in RNA Origins of Life

Can a replicase be found in the vast sequence space by random drift? We partially answer this question through a proof-of-concept study of the times of occurrence (hitting times) of some critical events in the origins of life for low-dimensional RNA sequences using a mathematical model and stochastic simulation studies from Python software. We parameterize fitness and similarity landscapes for polymerases and study a replicating population of sequences (randomly) participating in template-directed polymerization. Under the ansatz of localization where sequence proximity correlates with spatial proximity of sequences, we find that, for a replicating population of sequences, the hitting and establishment of a high-fidelity replicator depends critically on the polymerase fitness and sequence (spatial) similarity landscapes and on sequence dimension. Probability of hitting is dominated by landscape curvature, whereas hitting time is dominated by sequence dimension. Surface chemistries, compartmentalization, and decay increase hitting times. Compartmentalization by vesicles reveals a trade-off between vesicle formation rate and replicative mass, suggesting that compartmentalization is necessary to ensure sufficient concentration of precursors. Metabolism is thought to be necessary to replication by supplying precursors of nucleobase synthesis. We suggest that the dynamics of the search for a high-fidelity replicase evolved mostly during the final period and, upon hitting, would have been followed by genomic adaptation of genes and to compartmentalization and metabolism, effecting degree-of-freedom gains of replication channel control over domain and state to ensure the fidelity and safe operations of the primordial genetic communication system of life.

The Role of Proximity in Developing an Inter-Regional Innovation System

While most innovation collaboration projects consist of partners who are located at close proximity, recent literature has explored the development of innovation collaboration in the context of non-spatial proximity. Using a longitudinal mixed methods design, this article explores the inter-regional collaboration of triple helix partners from four non-contiguous European regions (Bucharest-Ilfov, Romania; Central Hungary, Hungary; Castilla-La Mancha, Spain; and South East, Ireland) which worked together to develop an inter-regional innovation system. The results from the study identified three non-spatial forms of proximity (social, cognitive and organisational) that were key determinants for developing the successful inter- regional innovation collaboration studied in this research. Based on the findings derived from this research, an inter-regional innovation system framework was developed to facilitate collaboration between stakeholders based in non-contiguous regions without them having to depend on geographical proximity. The major contributions of this research to theory and practice are the development of a novel framework for inter-regional innovation systems (iRIS) which can be applied by stakeholders in regions that want to collaborate from a distance. Furthermore, the research suggests that the substitution mechanism of geographical proximity consists of not just one non-spatial form, but it consists of the three non-spatial forms identified in this research.

Localized bank collapse or regional event?

This study presents a detailed synopsis of the sedimentological and structural features displayed within an underdescribed enigmatic facies observed in the basal Lower Jurassic Kayenta Formation of the Colorado Plateau. The facies comprises pebble to cobble-sized clasts of fine to medium-grained crossbedded sandstone with mud-draped and deformed foresets, as well as clasts of parallel-laminated but highly contorted siltstone and mudstone, supported in a silty to sandy matrix. The deposits are internally deformed and show both ductile and brittle structures in close spatial proximity, with a consistent and pervasive westdirected sense of shear. The facies occurs consistently within the same approximate stratigraphic interval, at or near the base of the Kayenta Formation. It is, however, observed only at four localities, distributed in a crudely linear arrangement parallel to the Utah-Idaho trough, despite extensive studies of outcrops of the same stratigraphic interval widely distributed across both Utah and Arizona. This study interprets the depositional processes as that of a partially subaerial debris flow with depositional events perhaps taking place during the waning period after ephemeral stream activity. The clast morphology and composition suggests a local source for the sediment entrained within the flow, and a limited transport distance. All of these observations are difficult to reconcile with the consistency of the stratigraphic interval in which the facies occur, or with the regional distribution of preserved examples. Consequently, this study discusses the potential for a common and time-equivalent triggering mechanism across all examples, which may have regional significance in the Jurassic evolution of the region.