DISPERSIVE FRACTAL CHARACTERIZATION OF KIDNEY ARTERIES BY THREE-DIMENSIONAL MASS-RADIUS-ANALYSIS

Fractals ◽  
1995 ◽  
Vol 03 (04) ◽  
pp. 879-891 ◽  
Author(s):  
M. SERNETZ ◽  
M. JUSTEN ◽  
F. JESTCZEMSKI
Keyword(s):  
Fractal Structure ◽  
Three Dimensional ◽  
Arterial System ◽  
Data Sets ◽  
Scaling Properties ◽  
Local Scaling ◽  
Living Organisms ◽  
Global And Local ◽  
First Time

Three-dimensional data sets of kidney arterial vessels were obtained from resin casts by serial sectioning and by micro-NMR-tomography, and were analyzed by the mass-radius-relation both for global and local scaling properties. We present for the first time the spatial resolution of local scaling and thus the dispersion of the fractal dimension within the organs. The arterial system is characterized as a non-homogeneous fractal. We discuss and relate the fractal structure to the scaling and allometry of metabolic rates in living organisms.

Diagnosis of COVID-19 using 3D CT scans and vaccination for COVID-19

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Gangadhar Ch ◽  
S. Jana ◽  
Sankararao Majji ◽  
Prathyusha Kuncha ◽  
Fantin Irudaya Raj E. ◽  
...  
Keyword(s):  
Virus Isolate ◽  
Research Work ◽  
Three Dimensional ◽  
Ct Scans ◽  
Data Sets ◽  
Content Type ◽  
Infected People ◽  
3D Data ◽  
Ct Classification ◽  
First Time

Purpose For the first time in a decade, a new form of pneumonia virus, coronavirus, COVID-19, appeared in Wuhan, China. To date, it has affected millions of people, killed thousands and resulted in thousands of deaths around the world. To stop the spread of this virus, isolate the infected people. Computed tomography (CT) imaging is very accurate in revealing the details of the lungs and allows oncologists to detect COVID. However, the analysis of CT scans, which can include hundreds of images, may cause delays in hospitals. The use of artificial intelligence (AI) in radiology could help to COVID-19-positive cancer in this manner is the main purpose of the work. Design/methodology/approach CT scans are a medical imaging procedure that gives a three-dimensional (3D) representation of the lungs for clinical purposes. The volumetric 3D data sets can be regarded as axial, coronal and transverse data sets. By using AI, we can diagnose the virus presence. Findings The paper discusses the use of an AI for COVID-19, and CT classification issue and vaccination details of COVID-19 have been detailed in this paper. Originality/value Originality of the work is, all the data can be collected genuinely and did research work doneown methodology.

scholarly journals Genetic characterization of a novel picornavirus in Algerian bats: co-evolution analysis of bat-related picornaviruses

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Safia Zeghbib ◽  
Róbert Herczeg ◽  
Gábor Kemenesi ◽  
Brigitta Zana ◽  
Kornélia Kurucz ◽  
...  
Keyword(s):  
Geographical Location ◽  
Data Sets ◽  
Evolutionary Analysis ◽  
Evolutionary Patterns ◽  
Host Genus ◽  
Evolution Analysis ◽  
Zoonotic Viruses ◽  
History Of ◽  
First Time

Abstract Bats are reservoirs of numerous zoonotic viruses. The Picornaviridae family comprises important pathogens which may infect both humans and animals. In this study, a bat-related picornavirus was detected from Algerian Minioptreus schreibersii bats for the first time in the country. Molecular analyses revealed the new virus originates to the Mischivirus genus. In the operational use of the acquired sequence and all available data regarding bat picornaviruses, we performed a co-evolutionary analysis of mischiviruses and their hosts, to authentically reveal evolutionary patterns within this genus. Based on this analysis, we enlarged the dataset, and examined the co-evolutionary history of all bat-related picornaviruses including their hosts, to effectively compile all possible species jumping events during their evolution. Furthermore, we explored the phylogeny association with geographical location, host-genus and host-species in both data sets.

scholarly journals Numerical Characterization of the Performance of Fluid Pumps Based on a Wankel Geometry

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Stephen Wan ◽  
Jason Leong ◽  
Te Ba ◽  
Arthur Lim ◽  
Chang Wei Kang
Keyword(s):  
Three Dimensional ◽  
Mechanical Efficiency ◽  
Planar Geometry ◽  
Pump Efficiency ◽  
Capacity Coefficient ◽  
Numerical Characterization ◽  
Pump Flow Rate ◽  
Low Efficiency ◽  
First Time

The performance of fluid pumps based on Wankel-type geometry, taking the shape of a double-lobed limaçon, is characterized. To the authors’ knowledge, this is the first time such an attempt has been made. To this end, numerous simulations for three different pump sizes were carried out and the results were understood in terms of the usual scaling coefficients. The results show that such pumps operate as low efficiency (<30%) valveless positive displacements pumps, with pump flow-rate noticeably falling at the onset of internal leakage. Also, for such pumps, the mechanical efficiency varies linearly with the head coefficient, and, within the onset of internal leakage, the capacity coefficient holds steady even across pump efficiency. Simulation of the flow field reveals a structure rich in three-dimensional vortices even in the laminar regime, including Taylor-like counterrotating vortex pairs, pointing towards the utility of these pumps in microfluidic applications. Given the planar geometry of such pumps, their applications as microreactors and micromixers are recommended.

A study of the mineralization of bone by high voltage EM tomography

1992 ◽  
Vol 50 (1) ◽  
pp. 582-583
Author(s):  
James Arena ◽  
Bruce F. McEwen ◽  
Min Ja Song ◽  
William J. Landis
Keyword(s):  
High Voltage ◽  
Three Dimensional ◽  
Structural Features ◽  
Complete Characterization ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
Vertebrate Model ◽  
Em Tomography ◽  
First Time

Complete characterization of the inorganic and organic interaction in calcifying tissues is fundamental to understanding their structure-function relations. In this context, high resolution tomographic three-dimensional (3D) reconstruction of normally calcifying avian tendon imaged by high voltage electron microscopy has recently been used to determine specific structural features of hydroxyapatite crystals associated with collagen fibrils in this vertebrate model of biological mineralization. The present work is an extension of these previous investigations, now applied to bone for the first time.

scholarly journals Fabrication, Experiments, and Analysis of an LBM Additive-Manufactured Flexure Parallel Mechanism

Micromachines ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 572 ◽  
Author(s):  
Huaxian Wei ◽  
Li Wang ◽  
Xiaodong Niu ◽  
Jian Zhang ◽  
Alessandro Simeone
Keyword(s):  
Additive Manufacturing ◽  
Parallel Mechanism ◽  
Three Dimensional ◽  
Experimental Tests ◽  
Element Analysis ◽  
Flexure Mechanism ◽  
Laser Beam Melting ◽  
Stiffness Characteristics ◽  
First Time

Additive manufacturing technology has advantages for realizing complex monolithic structures, providing huge potential for developing advanced flexure mechanisms for precision manipulation. However, the characteristics of flexure hinges fabricated by laser beam melting (LBM) additive manufacturing (AM) are currently little known. In this paper, the fabrication and characterization of a flexure parallel mechanism through the LBM process are reported for the first time to demonstrate the development of this technique. The geometrical accuracy of the additive-manufactured flexure mechanism was evaluated by three-dimensional scanning. The stiffness characteristics of the flexure mechanism were investigated through finite element analysis and experimental tests. The effective hinge thickness was determined based on the parameters study of the flexure parallel mechanism. The presented results highlight the promising outlook of LBM flexure parts for developing novel nanomanipulation platforms, while additional attention is required for material properties and manufacturing errors.

Organic–inorganic hybrid three-dimensional metal sulfite-oxalates with honeycomb-like structures

2017 ◽  
Vol 46 (18) ◽  
pp. 5911-5917 ◽  
Author(s):  
Ranjay K. Tiwari ◽  
J. N. Behera
Keyword(s):  
Three Dimensional ◽  
Hydrothermal Conditions ◽  
Inorganic Hybrid ◽  
Mixed Metal ◽  
First Time

The crystallographic signatures and characterization of two novel mixed metal hybrid open-frameworks [Na2Mn2(C2O4)(SO3)2(H2O)2], 1 and [NaEu(C2O4)(SO3)(H2O)3], 2 are reported for the first time; they are synthesized under hydrothermal conditions to generate 3D assemblies and honeycomb-like structures.

scholarly journals Biomacromolecules in recent phosphate-shelled brachiopods: identification and characterization of chitin matrix

2021 ◽  
Author(s):  
Oluwatoosin B. A. Agbaje ◽  
Glenn A. Brock ◽  
Zhifei Zhang ◽  
Kingsley C. Duru ◽  
Yue Liang ◽  
...  
Keyword(s):  
Organic Matrix ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Shallow Marine ◽  
The Core ◽  
Spectroscopic Analyses ◽  
Living Organisms ◽  
First Time ◽  
Identification And Characterization

Abstract Phosphate-shelled brachiopods differ in filter-feeding lifestyle, with Lingula anatina an active infaunal burrower, and Discinisca tenuis a shallow marine epibenthic animal. The shells of these animals are built of organophosphatic constituents, the organic fibres/sheets reinforced with calcium phosphate to provide a sophisticated ultrastructural robustness. This investigation examined the nature of the organic fibres in order to improve understanding of how living organisms produce hierarchically structured biomaterials. Unlike powdered samples commonly used in previous studies, organic fibres were isolated for the first time and the shell fractions were purified, in order to study the content and nature of the biopolymer fibres. Biochemical methods including Calcofluor staining revealed a chitin matrix. Ultrastructural analysis, thermal gravimetric analysis, and spectroscopic analyses show that the core polysaccharide framework is composed of layers of β-chitin sheets and/or fibrils that are coated with a fibrous organic matrix. There is more chitin matrix in the L. anatina shells (26.6 wt.%) compared to the D. tenuis shells (12.9 wt.%). Taken together, the data show that the chitin matrix contributes to increased skeletal strength, making L. anatina highly adapted for life as an active burrower. In comparison, D. tenuis contains less chitin and lives as attached epibenthos in a shallow marine environment. Graphical abstract First spectroscopic evidence of β-chitin sheets in recent organophosphatic brachiopods

scholarly journals Characterization of the planetary nebula Tc 1 based on VLT X-shooter observations

2019 ◽  
Vol 490 (2) ◽  
pp. 2475-2494 ◽  
Author(s):  
Isabel Aleman ◽  
Marcelo L Leal-Ferreira ◽  
Jan Cami ◽  
Stavros Akras ◽  
Bram Ochsendorf ◽  
...  
Keyword(s):  
Planetary Nebula ◽  
Three Dimensional ◽  
Central Star ◽  
Gas Temperature ◽  
Spatially Resolved ◽  
Morphological Model ◽  
Density Enhancement ◽  
First Time ◽  
The Empirical Analysis

ABSTRACT We present a detailed analysis of deep VLT/X-Shooter observations of the planetary nebula Tc 1. We calculate gas temperature, density, extinction, and abundances for several species from the empirical analysis of the total line fluxes. In addition, a spatially resolved analysis of the most intense lines provides the distribution of such quantities across the nebula. The new data reveal that several lines exhibit a double peak spectral profile consistent with the blue and redshifted components of an expanding spherical shell. The study of such components allowed us to construct for the first time a three-dimensional morphological model, which reveals that Tc 1 is a slightly elongated spheroid with an equatorial density enhancement seen almost pole on. A few bright lines present extended wings (with velocities up to a few hundred km s−1), but the mechanism producing them is not clear. We constructed photoionization models for the main shell of Tc 1. The models predict the central star temperature and luminosity, as well as the nebular density and abundances similar to previous studies. Our models indicate that Tc 1 is located at a distance of approximately 2 kpc. We report the first detection of the [Kr iii] 6825 Å emission line, from which we determine the Krypton abundance. Our model indicates that the main shell of Tc 1 is matter bounded; leaking H ionizing photons may explain the ionization of its faint AGB-remnant halo.

Characterization of the three-dimensional residual stress distribution in SiC bulk crystals by neutron diffraction

CrystEngComm ◽  
2017 ◽  
Vol 19 (43) ◽  
pp. 6527-6532 ◽  
Author(s):  
Xuejian Xie ◽  
Xiaobo Hu ◽  
Xiufang Chen ◽  
Fafu Liu ◽  
Xianglong Yang ◽  
...  
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Neutron Diffraction ◽  
Three Dimensional ◽  
Diffraction Method ◽  
Residual Stress Distribution ◽  
Bulk Crystals ◽  
First Time ◽  
Neutron Diffraction Method

The neutron diffraction method was adopted to study the three-dimensional residual stress distribution in SiC bulk crystals for the first time.

scholarly journals Characterization of GPX1 and DIO1 Genes in Bubalus Bubalis

2012 ◽  
Vol 4 (1) ◽  
Author(s):  
Vandana Dureja ◽  
Sumer Singh ◽  
S Rana ◽  
P Banerjee ◽  
J Joshi ◽  
...  
Keyword(s):  
Active Form ◽  
Bubalus Bubalis ◽  
Main Function ◽  
Exon 2 ◽  
Iodothyronine Deiodinases ◽  
Exon 1 ◽  
Selenoprotein Genes ◽  
Living Organisms ◽  
First Time

Selenoprotein genes contain selenium in the form of selenocysteine which is involved in protecting the cells from oxidative stress. Soils in India differ greatly in selenium concentrations affecting feed stuffs for selenium availability. Selenoproteins have recently been identified in variety of living organisms including humans which have 25 selenoprotein genes. Among these families of selenoprotein genes, we sequenced Gpx1 gene (Glutathione peroxidases1) and Dio1 gene (Iodothyronine deiodinases) in Bubalus bubalis. Gpx1 is most abundant and ubiquitously expressed selenoprotein which helps to protect against the damaging effects of hydrogen peroxide and oxygen rich free radicals whereas Dio1 is expressed mainly in liver, thyroid gland and adipose tissue, its main function is to convert tetraiodothyronine (T4)  to its active form thyroxine (T3) in the presence of deiodinases enzyme. The main aim of the study was to characterize these two genes and to find out the buffalo specific SNPs. This was accomplished by designing primers using cattle database and sequencing a panel of 24 samples consisting of 6 diverse breeds of buffalo. Gpx1 consisted of 2 exons (Accession ID: JQ031269) while Dio1 comprised 4 exons (Accession ID: JQ791197). In Gpx1 gene, 9 SNPs were recorded and 4 were non synonymous, changing amino acid were distributed equally in both exon. In exon 1, A141G (aa Q5R) and G161A (aa A12T); and in exon 2 C785T (aa R132W) and A808T (aa S139R). In Dio1 gene, 3 non synonymous SNPs were identified at A188G (aa H22R), C215G (aa T31R) and G941A (aa V146I). These SNPs are novel and reported for the first time in Indian buffalo and has a potential for their use in diversity analysis and association with various selenium related traits.

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