The Asymmetric Pattern of Population Mobility during the Spring Festival in the Yangtze River Delta Based on Complex Network Analysis: An Empirical Analysis of “Tencent Migration” Big Data

Population mobility patterns are an important reflection of the future distribution of migrant populations and the evolution trends of urbanization patterns. However, although research based on statistical data can reveal the pattern of population flow, it also shows a time lag. Most of the population flow network research based on location services data has failed to fully discuss the symmetry of directional outflows and inflows in the same place and the two-way symmetrical connections between places. This paper creatively proposes and constructs the concept and analysis framework of population flow asymmetry. We used the Yangtze River Delta (YRD) as a typical case and the results of our analysis reveal the temporal and spatial asymmetry of the population flow using complex network analysis methods based on the Spring Festival (SF) population migration big data. We found that the timing asymmetry manifested in such a way that the closer it was to the festival, the greater the scale and intensity of the population movement. This is a feature of the lack of scale and regional differences within China. The spatial asymmetry was manifested in three aspects, network, node, and link, and the core cities with administrative and economic hierarchical advantages dominated the asymmetric pattern of regional population mobility. In addition, distance and administrative boundaries are factors that cannot be ignored in population movements, and they were implicated in the degree of asymmetry by distance enhancement and administrative boundary blocking. The conclusions of this study can not only provide policy decision-making guidelines for population management and resource allocation in the YRD, but they can also provide a reference value for achieving the goal of regional, high-quality, integrated development. Future research will further the discussion and management of socio-economic attributes in order to develop a more detailed and microscopic understanding of the mechanisms of population mobility patterns.

Infrastructure investment projects: financing and management mechanisms

Purpose This paper analyses the modern market for project finance, its sectorial structure and main development trends. This study aims to form a constructive diagnostic toolkit for investment support of infrastructure design in regions, taking into account spatial asymmetry in the context of an integrated management approach. Design/methodology/approach When analyzing the public–private partnership (PPP) project performance, it is reasonable to distinguish the following two levels of discount rates: state and private. To achieve a high level of development of the general infrastructure of a region, a conceptual approach to the formation of investment support for the development of regional infrastructure has been developed. Findings The scientific contribution of this study is to improve the approach to modeling investment support for regional infrastructure design in the context of spatial asymmetry. Implementation of infrastructure projects creates prerequisites for sustainable economic growth, improvement in business and investment and social attractiveness of the national economy and its regions. Practical implications The practical significance of this study is that its main provisions allow for an effective regional socio-economic policy, based on the systemic development of regional infrastructure and aim at boosting competitiveness. Originality/value Recommendations can be used by regional and local authorities to formulate a socio-economic strategy for regional development as well as by representatives of private business who intend to engage in regional PPP projects.

Nonreciprocal and Directional Wave Propagation in a Two-Dimensional Lattice With Bilinear Properties

A passive method of realizing nonreciprocal wave propagation in a two-dimensional (2D) lattice is proposed, using bilinear springs combined with the necessary spatial asymmetry to provide a stable and strong departure from reciprocity. The bilinear property is unique among nonlinear mechanisms in that it is independent of amplitude but sensitive to the sign of the wave motion; the 2D setup allows the flexibility of generating spatial asymmetry at both small and large scales. The starting point is a linear 2D monatomic spring-mass lattice with strong directionally dependent wave propagation. The source and receiver are aligned so that there is virtually no direct wave transmission between them. Adding a region of bilinearity combined with spatial asymmetry that is not in the direct path between the source and receiver causes signal transmission via nonreciprocal scattering. A variety of spatially asymmetric bilinear configurations are considered, ranging from compact modulations confined within the unit cell to extended ones over the whole section, to obtain different dynamic nonreciprocal effects. Simulations illustrate how the combination of bilinearity and spatial asymmetry ensures a passive amplitude-independent nonreciprocal 2D system for a variety of different excitations.

Low-cost laser-cut patterned chips for acoustic concentration of micro to nano particles and cells by operating over a wide frequency range

Acoustofluidic platforms for cell manipulation benefit from being contactless and label-free at potentially low cost. Particle concentration in a droplet relies on augmenting spatial asymmetry in the acoustic field, which...

Cell Scientist to Watch – Eurico Morais-de-Sá

ABSTRACTEurico Morais-de-Sá graduated in biochemistry from the University of Porto, Portugal. After a research internship in protein crystallography at the Institute for Molecular and Cell Biology (IBMC) in Porto, Eurico moved to Cambridge, UK, to do his PhD with Daniel St Johnston at the Gurdon Institute. During this time, he studied cell polarity in the context of epithelial tissue and body-axis specification. In 2011, he was awarded EMBO and Marie Curie fellowships to return to Porto for his postdoctoral work with Claudio Sunkel at IBMC, where he used his cell polarity expertise to understand the regulatory processes of epithelial cell division. In 2018, Eurico established his own research group at Instituto de Inovação e Investigação em Saúde (i3S) focusing on the mechanisms by which epithelial cells modulate spatial asymmetry during cell division to maintain the function and integrity of proliferative tissues.

The Smart specialisation’s methodology in overcoming the spatial asymmetry of Russia’s economic federalism

The unevenness in development of the Russian regions has risen dramatically over the last one and a half decade, the interregional gap in the main socioeconomic indicators has widened, all of this threatening the integration of economic space and unity of federalism rela tions. The paper studies the problem of Russia’s spatial asymmetry in conditions of economic federalism, which is not comprehensively addressed by the currently adopted federate policy. Methodologically the research relies on spatial and regional economics, as well as takes on the concept of Smart specialisation. The author identifies six groups of Russia’s territories accord ing to their functional role in a federal state, and assesses spatial asymmetry of the territories in terms of industrial, budgetary and social components of the economic federalism through the lens of the regions’ functional specialisation using statistical methods. Based on the obtained measures of variation and dispersion the author concludes about a higher asymmetry and ir regularity in the country generally, than within the groups of regions having one specialisation despite the fact that the groups consist of regions with different level of economic development. The findings of the analysis allow theoretically justifying the necessity of changing the direction of the economic federalism policy to reduce the asymmetry of regional development. The au thor suggests adopting a new model of the relations between the federal center and the regions, which implies a transition from the presently applied levelling to the state regulation of the regions based on their specialisation. The proposed model of federalism involves differentiat ing measures of the state regulation and support of regions depending on their economic and political specialisation.

Evolution of brain lateralization: A shared hominid pattern of endocranial asymmetry is much more variable in humans than in great apes

Brain lateralization is commonly interpreted as crucial for human brain function and cognition. However, as comparative studies among primates are rare, it is not known which aspects of lateralization are really uniquely human. Here, we quantify both pattern and magnitude of brain shape asymmetry based on endocranial imprints of the braincase in humans, chimpanzees, gorillas, and orangutans. Like previous studies, we found that humans were more asymmetric than chimpanzees, however so were gorillas and orangutans, highlighting the need to broaden the comparative framework for interpretation. We found that the average spatial asymmetry pattern, previously considered to be uniquely human, was shared among humans and apes. In humans, however, it was less directed, and different local asymmetries were less correlated. We, thus, found human asymmetry to be much more variable compared with that of apes. These findings likely reflect increased functional and developmental modularization of the human brain.

Nonreciprocal propagation in a non-Hermitian silicon photonic coupler employing graphene saturable absorption

We present the concept, analysis and design of a nonreciprocal system of coupled nonlinear waveguides, operating at the near infrared. We exploit the spatial asymmetry induced by the exceptional points of a non-Hermitian coupler which, combined with saturable absorption in the nonlinear regime, can break Lorentz reciprocity. In this work, we introduce asymmetric losses in a pair of coupled silicon waveguides by overlaying only one of them with unbiased graphene, subject to saturable absorption. The device can be used as a broadband half-duplex isolator: a two-port component offering unidirectional transmission of high-power signals.