172 research outputs found
Urban spatial structures from human flow by Hodge-Kodaira decomposition
Human flow in cities indicates social activity and can reveal urban spatial
structures based on human behaviours for relevant applications. Scalar
potential is a mathematical concept, and if successfully introduced, it can
provide an intuitive perspective of human flow. However, the definition of such
a potential to the origin-destination flow matrix and determination of its
plausibility remain unsolved. Here, we apply Hodge-Kodaira decomposition, in
which a matrix is uniquely decomposed into a potential-driven (gradient) flow
and a curl flow. We depict the potential landscapes in cities due to commuting
flow and reveal how the landscapes have been changed or unchanged by years or
transport methods. We then determine how well the commuting flow is described
by the potential, by evaluating the percentage of the gradient component for
metropolitan areas in the USA and show that the gradient component is almost
100\% in several areas; in other areas, however, the curl component is
dominant, indicating the importance of circular flow along triangles of places.
The potential landscape provides an easy-to-use visualisation tool to show the
attractive places of human flow and will aid in various applications in
commerce, urban design, and epidemic spreading
Towards dynamical network biomarkers in neuromodulation of episodic migraine
Computational methods have complemented experimental and clinical
neursciences and led to improvements in our understanding of the nervous
systems in health and disease. In parallel, neuromodulation in form of electric
and magnetic stimulation is gaining increasing acceptance in chronic and
intractable diseases. In this paper, we firstly explore the relevant state of
the art in fusion of both developments towards translational computational
neuroscience. Then, we propose a strategy to employ the new theoretical concept
of dynamical network biomarkers (DNB) in episodic manifestations of chronic
disorders. In particular, as a first example, we introduce the use of
computational models in migraine and illustrate on the basis of this example
the potential of DNB as early-warning signals for neuromodulation in episodic
migraine.Comment: 13 pages, 5 figure
Involvement of Fusobacterium Species in Oral Cancer Progression : A Literature Review Including Other Types of Cancer
Chronic inflammation caused by infections has been suggested to be one of the most important cause of cancers. It has recently been shown that there is correlation between intestinal bacteria and cancer development including metastasis. As over 700 bacterial species exist in an oral cavity, it has been concerning that bacterial infection may cause oral cancer. However, the role of bacteria regarding tumorigenesis of oral cancer remains unclear. Several papers have shown that Fusobacterium species deriving the oral cavities, especially, play a crucial role for the development of colorectal and esophageal cancer. F. nucleatum is a well-known oral bacterium involved in formation of typical dental plaque on human teeth and causing periodontal diseases. The greatest characteristic of F. nucleatum is its ability to adhere to various bacteria and host cells. Interestingly, F. nucleatum is frequently detected in oral cancer tissues. Moreover, detection of F. nucleatum is correlated with the clinical stage of oral cancer. Although the detailed mechanism is still unclear, Fusobacterium species have been suggested to be associated with cell adhesion, tumorigenesis, epithelial-to-mesenchymal transition, inflammasomes, cell cycle, etc. in oral cancer. In this review, we introduce the reports focused on the association of Fusobacterium species with cancer development and progression including oral, esophageal, and colon cancers
Stabilization of a honeycomb lattice of IrO octahedra in superlattices with ilmenite-type MnTiO
In the quest for quantum spin liquids, thin films are expected to open the
way for the control of intricate magnetic interactions in actual materials by
exploiting epitaxial strain and two-dimensionality. However, materials
compatible with conventional thin-film growth methods have largely remained
undeveloped. As a promising candidate towards the materialization of quantum
spin liquids in thin films, we here present a robust ilmenite-type oxide with a
honeycomb lattice of edge-sharing IrO octahedra artificially stabilized by
superlattice formation with an ilmenite-type antiferromagnetic oxide MnTiO.
The stabilized sub-unit-cell-thick Mn-Ir-O layer is isostructural to MnTiO,
having the atomic arrangement corresponding to ilmenite-type MnTiO not
discovered yet. By spin Hall magnetoresistance measurements, we found that
antiferromagnetic ordering in the ilmenite Mn sublattice is suppressed by
modified magnetic interactions in the MnO planes via the IrO planes.
These findings lay the foundation for the creation of two-dimensional Kitaev
candidate materials, accelerating the discovery of exotic physics and
applications specific to quantum spin liquids
Psychological resilience is correlated with dynamic changes in functional connectivity within the default mode network during a cognitive task
Resilience is a dynamic process that enables organisms to cope with demanding environments. Resting-state functional MRI (fMRI) studies have demonstrated a negative correlation between resilience and functional connectivities (FCs) within the default mode network (DMN). Considering the on-demand recruitment process of resilience, dynamic changes in FCs during cognitive load increases may reflect essential aspects of resilience. We compared DMN FC changes in resting and task states and their association with resilience. Eighty-nine healthy volunteers completed the Connor–Davidson Resilience Scale (CD-RISC) and an fMRI with an auditory oddball task. The fMRI time series was divided into resting and task periods. We focused on FC changes between the latter half of the resting period and the former half of the task phase (switching), and between the former and latter half of the task phase (sustaining). FCs within the ventral DMN significantly increased during “switching” and decreased during “sustaining”. For FCs between the retrosplenial/posterior cingulate and the parahippocampal cortex, increased FC during switching was negatively correlated with CD-RISC scores. In individuals with higher resilience, ventral DMN connectivities were more stable and homeostatic in the face of cognitive demand. The dynamic profile of DMN FCs may represent a novel biomarker of resilience
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