Size, Shape, and Spatial Distribution Analysis of Sub-Micron Hip Implant Wear Particles at Sub-Optical Resolution Using Deconvolution Methods

2021 ◽  
Author(s):  
Andrew Carter Erwin
Keyword(s):  
Spatial Distribution ◽  
Optical Resolution ◽  
Distribution Analysis ◽  
Wear Particles ◽  
Hip Implant ◽  
Implant Wear

Spatial Distribution Analysis of Attributes of Rock Joints Using Geomathematical Methods.

1996 ◽  
Vol 112 (13) ◽  
pp. 907-914 ◽  
Author(s):  
Katsuaki KOIKE ◽  
Yoshifumi NOGUCHI ◽  
Hiroshi IWASAKI ◽  
Katsuhiko KANEKO
Keyword(s):  
Spatial Distribution ◽  
Rock Joints ◽  
Distribution Analysis

Niche Sharing in Intertidal Mollusks and Decapods in Rocky Shore of Easter Island

2019 ◽  
Vol 53 (5) ◽  
pp. 417-422
Author(s):  
P. De los Ríos ◽  
E. Ibáñez Arancibia
Keyword(s):  
Spatial Distribution ◽  
Negative Binomial Distribution ◽  
Binomial Distribution ◽  
Rocky Shore ◽  
Negative Binomial ◽  
Null Model ◽  
Easter Island ◽  
Published Data ◽  
Distribution Analysis ◽  
Field Works

Abstract The coastal marine ecosystems in Easter Island have been poorly studied, and the main studies were isolated species records based on scientific expeditions. The aim of the present study is to apply a spatial distribution analysis and niche sharing null model in published data on intertidal marine gastropods and decapods in rocky shore in Easter Island based in field works in 2010, and published information from CIMAR cruiser in 2004. The field data revealed the presence of decapods Planes minutus (Linnaeus, 1758) and Leptograpsus variegatus (Fabricius, 1793), whereas it was observed the gastropods Nodilittorina pyramidalis pascua Rosewater, 1970 and Nerita morio (G. B. Sowerby I., 1833). The available information revealed the presence of more species in data collected in 2004 in comparison to data collected in 2010, with one species markedly dominant in comparison to the other species. The spatial distribution of species reported in field works revealed that P. minutus and N. morio have aggregated pattern and negative binomial distribution, L. variegatus had uniform pattern with binomial distribution, and finally N. pyramidalis pascua, in spite of aggregated distribution pattern, had not negative binomial distribution. Finally, the results of null model revealed that the species reported did not share ecological niche due to competition absence. The results would agree with other similar information about littoral and sub-littoral fauna for Easter Island.

scholarly journals Size-resolved spatial distribution analysis of aerosols with or without the utilization of a novel aerosol containment device in dental settings

2021 ◽  
Vol 33 (8) ◽  
pp. 085102
Author(s):  
Fernando Luis Esteban Florez ◽  
Tyler Thibodeau ◽  
Toluwanimi Oni ◽  
Evan Floyd ◽  
Sharukh S. Khajotia ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Distribution Analysis

scholarly journals A simple method of suspending implant wear particles for more physiological modelling of cell-particle interactions in vitro

2021 ◽  
Author(s):  
Christine Poon
Keyword(s):  
Wear Debris ◽  
Culture Media ◽  
Polymeric Materials ◽  
Wear Particle ◽  
Physicochemical Characteristics ◽  
Wear Particles ◽  
Simple Method ◽  
Implant Wear

AbstractArthroplasty implants e.g. hip, knee, spinal disc sustain relatively high compressive loading and friction wear, which lead to the formation of wear particles or debris between articulating surfaces. Despite advances in orthopaedic materials and surface treatments, the production of wear debris from any part of a joint arthroplasty implant is currently unavoidable. Implant wear debris induces host immune responses and inflammation, which causes patient pain and ultimately implant failure through progressive inflammation-mediated osteolysis and implant loosening, where the severity and rate of periprosthetic osteolysis depends on the material and physicochemical characteristics of the wear particles. Evaluating the cytotoxicity of implant wear particles is important for regulatory approved clinical application of arthroplasty implants, as is the study of cell-particle response pathways. However, the wear particles of polymeric materials commonly used for arthroplasty implants tend to float when placed in culture media, which limits their contact with cell cultures. This study reports a simple means of suspending wear particles in liquid medium using sodium carboxymethyl cellulose (NaCMC) to provide a more realistic proxy of the interaction between cells and tissues to wear particles in vivo, which are free-floating in synovial fluid within the joint cavity. Low concentrations of NaCMC dissolved in culture medium were found to be effective for suspending polymeric wear particles. Such suspensions may be used as more physiologically-relevant means for testing cellular responses to implant wear debris, as well as studying the combinative effects of shear and wear particle abrasion on cells in a dynamic culture environments such as perfused tissue-on-chip devices.

scholarly journals The Spatial and Cell-Type Distribution of SARS-CoV-2 Receptor ACE2 in the Human and Mouse Brains

2021 ◽  
Vol 11 ◽  
Author(s):  
Rongrong Chen ◽  
Keer Wang ◽  
Jie Yu ◽  
Derek Howard ◽  
Leon French ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Spatial Distribution ◽  
Host Cells ◽  
Inhibitory Neurons ◽  
Middle Temporal Gyrus ◽  
Distribution Analysis ◽  
Cell Type ◽  
Type Distribution ◽  
The Brain ◽  
Human And Mouse

By engaging angiotensin-converting enzyme 2 (ACE2 or Ace2), the novel pathogenic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) invades host cells and affects many organs, including the brain. However, the distribution of ACE2 in the brain is still obscure. Here, we investigated the ACE2 expression in the brain by analyzing data from publicly available brain transcriptome databases. According to our spatial distribution analysis, ACE2 was relatively highly expressed in some brain locations, such as the choroid plexus and paraventricular nuclei of the thalamus. According to cell-type distribution analysis, nuclear expression of ACE2 was found in many neurons (both excitatory and inhibitory neurons) and some non-neuron cells (mainly astrocytes, oligodendrocytes, and endothelial cells) in the human middle temporal gyrus and posterior cingulate cortex. A few ACE2-expressing nuclei were found in a hippocampal dataset, and none were detected in the prefrontal cortex. Except for the additional high expression of Ace2 in the olfactory bulb areas for spatial distribution as well as in the pericytes and endothelial cells for cell-type distribution, the distribution of Ace2 in the mouse brain was similar to that in the human brain. Thus, our results reveal an outline of ACE2/Ace2 distribution in the human and mouse brains, which indicates that the brain infection of SARS-CoV-2 may be capable of inducing central nervous system symptoms in coronavirus disease 2019 (COVID-19) patients. Potential species differences should be considered when using mouse models to study the neurological effects of SARS-CoV-2 infection.

scholarly journals MODELING THE SPATIAL DISTRIBUTION OF ESHNAN (SEIDLITZIA ROSMARINUS) SHRUBS TO EXPLORING THEIR ECOLOGICAL INTERACTIONS IN DRYLANDS OF CENTRAL IRAN

2015 ◽  
Vol XL-1-W5 ◽  
pp. 163-168 ◽  
Author(s):  
Y. Erfanifard ◽  
E. Khosravi
Keyword(s):  
Distribution Function ◽  
Spatial Distribution ◽  
Pair Correlation ◽  
Central Iran ◽  
Arid Ecosystems ◽  
Positive Interactions ◽  
Distribution Analysis ◽  
Summary Statistics ◽  
Plant Interactions ◽  
Intraspecific Interactions

Evaluating the interactions of woody plants has been a major research topic of ecological investigations in arid ecosystems. Plant-plant interactions can shift from positive (facilitation) to negative (competition) depending on levels of environmental stress and determine the spatial pattern of plants. The spatial distribution analysis of plants via different summary statistics can reveal the interactions of plants and how they influence one another. An aggregated distribution indicates facilitative interactions among plants, while dispersion of species reflects their competition for scarce resources. This study was aimed to explore the intraspecific interactions of eshnan (<i>Seidlitzia rosmarinus</i>) shrubs in arid lands, central Iran, using different summary statistics (i.e., pair correlation function g(<i>r</i>), O-ring function O(<i>r</i>), nearest neighbour distribution function D(<i>r</i>), spherical contact distribution function Hs(<i>r</i>)). The observed pattern of shrubs showed significant spatial heterogeneity as compared to inhomogeneous Poisson process (α=0.05). The results of g(<i>r</i>) and O(<i>r</i>) revealed the significant aggregation of eshnan shrubs up to scale of 3 m (α=0.05). The results of D(<i>r</i>) and Hs(<i>r</i>) also showed that maximum distance to nearest shrub was 6 m and the distribution of the sizes of gaps was significantly different from random distribution up to this spatial scale. In general, it was concluded that there were positive interactions between eshnan shrubs at small scales and they were aggregated due to their intraspecific facilitation effects in the study area.

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