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

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Dimitrios Tsiotas ◽  
Vassilis Tselios
Keyword(s):  
Three Dimensional ◽  
Virus Transmission ◽  
Spatial Proximity ◽  
Node Degree ◽  
Economic Openness ◽  
Interconnected System ◽  
Critical Determinant ◽  
Spatio Temporal ◽  
Cutting Point ◽  
Temporal Spread

AbstractThe 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.

scholarly journals SPATIO-TEMPORAL DATA ANALYSIS WITH NON-LINEAR FILTERS: BRAIN MAPPING WITH fMRI DATA

2011 ◽  
Vol 19 (3) ◽  
pp. 189
Author(s):  
Karsten Rodenacker ◽  
Klaus Hahn ◽  
Gerhard Winkler ◽  
Dorothea P Auer
Keyword(s):  
Signal To Noise Ratio ◽  
Three Dimensional ◽  
Digital Data ◽  
Linear Filters ◽  
Brain Functions ◽  
Non Linear ◽  
Long Time ◽  
Spatio Temporal ◽  
Sensory Activation ◽  
Temporal Data Analysis

Spatio-temporal digital data from fMRI (functional Magnetic Resonance Imaging) are used to analyse and to model brain activation. To map brain functions, a well-defined sensory activation is offered to a test person and the hemodynamic response to neuronal activity is studied. This so-called BOLD effect in fMRI is typically small and characterised by a very low signal to noise ratio. Hence the activation is repeated and the three dimensional signal (multi-slice 2D) is gathered during relatively long time ranges (3-5 min). From the noisy and distorted spatio-temporal signal the expected response has to be filtered out. Presented methods of spatio-temporal signal processing base on non-linear concepts of data reconstruction and filters of mathematical morphology (e.g. alternating sequential morphological filters). Filters applied are compared by classifications of activations.

Unsteady Hemodynamics in Intracranial Aneurysms With Varying Dome Orientations

2021 ◽  
Vol 143 (6) ◽  
Author(s):  
Abdullah Y. Usmani ◽  
K. Muralidhar
Keyword(s):  
Intracranial Aneurysm ◽  
Three Dimensional ◽  
Parent Artery ◽  
Fluid Loading ◽  
Image Velocimetry ◽  
Flow Reynolds Number ◽  
Fatal Hemorrhage ◽  
Wall Loading ◽  
Spatio Temporal ◽  
Finite Volume Simulation

Abstract Fluid loading within an intracranial aneurysm is difficult to measure but can be related to the shape of the flow passage. The outcome of excessive loading is a fatal hemorrhage, making it necessary for early diagnosis. However, arterial diseases are asymptomatic and clinical assessment is a challenge. A realistic approach to examining the severity of wall loading is from the morphology of the aneurysm itself. Accordingly, this study compares pulsatile flow (Reynolds number Re = 426, Womersley number Wo = 4.7) in three different intracranial aneurysm geometries. Specifically, the spatio-temporal movement of vortices is followed in high aspect ratio aneurysm models whose domes are inclined along with angles of 0, 45, and 90 deg relative to the plane of the parent artery. The study is based on finite volume simulation of unsteady three-dimensional flow while a limited set of particle image velocimetry experiments have been carried out. Within a pulsatile cycle, an increase in inclination (0–90 deg) is seen to shift the point of impingement from the distal end toward the aneurysmal apex. This change in flow pattern strengthens helicity, drifts vortex cores, enhances spatial displacement of the vortex, and generates skewed Dean's vortices on transverse planes. Patches of wall shear stress and wall pressure shift spatially from the distal end in models of low inclination (0–45 deg) and circumscribe the aneurysmal wall for an inclination angle of 90 deg. Accordingly, it is concluded that high angles of inclination increase rupture risks while lower inclinations are comparatively safe.

SIMULATING THE SPATIO-TEMPORAL SPREAD OF COOLING FLUX IN CARDIAC TISSUE DUE TO CATHETERIZED CRYOABLATION

2010 ◽  
Author(s):  
Michael Seger ◽  
Gerald Fischer ◽  
Michael Handler ◽  
Florian Hintringer ◽  
Christian Baumgartner
Keyword(s):  
Cardiac Tissue ◽  
Spatio Temporal ◽  
Temporal Spread

Mining in Spatio-Temporal Databases

2011 ◽  
pp. 272-293
Author(s):  
Junmei Wang ◽  
Wynne Hsu ◽  
Mong Li Lee
Keyword(s):  
Spatial Databases ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Temporal Databases ◽  
Temporal Data ◽  
Service Patterns ◽  
Sequence Patterns ◽  
Spatial Coordinates ◽  
Spatio Temporal ◽  
Work Done

Recent interest in spatio-temporal applications has been fueled by the need to discover and predict complex patterns that occur when we observe the behavior of objects in the three-dimensional space of time and spatial coordinates. Although the complex and intrinsic relationships among the spatio-temporal data limit the usefulness of conventional data mining techniques to discover the patterns in the spatio-temporal databases, they also lead to opportunities for mining new classes of patterns in spatio-temporal databases. This chapter provides a survey of the work done for mining patterns in spatial databases and temporal databases, and the preliminary work for mining patterns in spatio-temporal databases. We highlight the unique challenges of mining interesting patterns in spatio-temporal databases. We also describe two special types of spatio-temporal patterns: location-sensitive sequence patterns and geographical features for location-based service patterns.

scholarly journals Extended Dual-Focus Microscopy for Ratiometric-Based 3D Movement Tracking

2020 ◽  
Vol 10 (18) ◽  
pp. 6243
Author(s):  
Seohyun Lee ◽  
Hyuno Kim ◽  
Hideo Higuchi
Keyword(s):  
Drug Delivery ◽  
High Resolution ◽  
Optical Axis ◽  
Three Dimensional ◽  
Virus Transmission ◽  
Living Cells ◽  
Depth Of Field ◽  
Objective Lens ◽  
Accurate Localization ◽  
Movement Tracking

Imaging the three-dimensional movement of small organelles in living cells can provide key information for the dynamics of drug delivery and virus transmission in biomedical disciplines. To stably monitor such intracellular motion using microscope, long depth of field along optical axis and accurate three-dimensional tracking are simultaneously required. In the present work, we suggest an extended dual-focus optics microscopy system by combining a bifocal plane imaging scheme and objective lens oscillation, which enables accurate localization for a long axial range. The proposed system exploits high-resolution functionality by concatenating partial calibration result acquired each axial imaging level, maintaining the practical advantages of ratiometric method.

scholarly journals Adenine DNA methylation, 3D genome organization, and gene expression in the parasiteTrichomonas vaginalis

2020 ◽  
Vol 117 (23) ◽  
pp. 13033-13043
Author(s):  
Ayelen Lizarraga ◽  
Zach Klapholz O’Brown ◽  
Konstantinos Boulias ◽  
Lara Roach ◽  
Eric Lieberman Greer ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Methylation ◽  
Trichomonas Vaginalis ◽  
Three Dimensional ◽  
Wide Distribution ◽  
Spatial Proximity ◽  
Regulation Of Transcription ◽  
3D Genome ◽  
Intergenic Regions ◽  
Close Spatial Proximity

Trichomonas vaginalisis a common sexually transmitted parasite that colonizes the human urogenital tract causing infections that range from asymptomatic to highly inflammatory. Recent works have highlighted the importance of histone modifications in the regulation of transcription and parasite pathogenesis. However, the nature of DNA methylation in the parasite remains unexplored. Using a combination of immunological techniques and ultrahigh-performance liquid chromatography (UHPLC), we analyzed the abundance of DNA methylation in strains with differential pathogenicity demonstrating that N6-methyladenine (6mA), and not 5‐methylcytosine (5mC), is the main DNA methylation mark inT. vaginalis. Genome-wide distribution of 6mA reveals that this mark is enriched at intergenic regions, with a preference for certain superfamilies of DNA transposable elements. We show that 6mA inT. vaginalisis associated with silencing when present on genes. Interestingly, bioinformatics analysis revealed the presence of transcriptionally active or repressive intervals flanked by 6mA-enriched regions, and results from chromatin conformation capture (3C) experiments suggest these 6mA flanked regions are in close spatial proximity. These associations were disrupted when parasites were treated with the demethylation activator ascorbic acid. This finding revealed a role for 6mA in modulating three-dimensional (3D) chromatin structure and gene expression in this divergent member of the Excavata.

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