Mathematical Classification of the Spiral and Ring Galaxy Morphologies Based on the Fractional Trigonometry

Author(s):  
Carl F. Lorenzo ◽  
Tom T. Hartley

The ongoing development of the fractional trigonometry has created a new set of spiral functions, the fractional spiral functions. These spirals include both barred and normal spirals in a common formulation. This paper studies the applicability of the fractional spirals to the mathematical classification of spiral and ring galaxy morphologies. The fractional spirals are found to provide a high quality fit to a variety of ring and spiral galaxies over a significant range of the spiral length. Further, the r–s character of the de Vaucouleurs classification is found to relate to particular parameters of the spirals. Additional benefits include; direct inference of galaxies inclination, estimates of major deviations of the galaxy optical center from the geometric center, and further application of the mathematical description of the galaxy morphology.

2018 ◽  
Vol 48 (4) ◽  
pp. 564-588 ◽  
Author(s):  
Dick Kasperowski ◽  
Thomas Hillman

In the past decade, some areas of science have begun turning to masses of online volunteers through open calls for generating and classifying very large sets of data. The purpose of this study is to investigate the epistemic culture of a large-scale online citizen science project, the Galaxy Zoo, that turns to volunteers for the classification of images of galaxies. For this task, we chose to apply the concepts of programs and antiprograms to examine the ‘essential tensions’ that arise in relation to the mobilizing values of a citizen science project and the epistemic subjects and cultures that are enacted by its volunteers. Our premise is that these tensions reveal central features of the epistemic subjects and distributed cognition of epistemic cultures in these large-scale citizen science projects.


2017 ◽  
Vol 7 (2) ◽  
pp. 200-211 ◽  
Author(s):  
Evan W. Matshes ◽  
Emma O. Lew

Recent evidence indicates that with thorough, high quality death investigations and autopsies, forensic pathologists have recognized that many unexpected infant deaths are, in fact, asphyxial in nature. With this recognition has come a commensurate decrease in, and in some cases, abolition of, the label “sudden infant death syndrome” (SIDS). Current controversies often pertain to how and why some infant deaths are determined to be asphyxial in nature and whether or not apparent asphyxial circumstances are risk factors for SIDS, or rather, harbingers of asphyxial deaths. In an effort to sidestep these controversies, some forensic pathologists elected to instead use the noncommittal label “sudden unexpected infant death” (SUID), leading to the unfortunate consequence of SUID – like SIDS – gaining notoriety as an actual disease that could be diagnosed, studied, and ultimately cured. Although it is not possible to provide death certification guidance for every conceivable type of unexpected infant death, we recognize and propose a simple classification system for overarching themes that cover the vast majority of cases where infants die suddenly and unexpectedly.


2018 ◽  
Vol 618 ◽  
pp. A149 ◽  
Author(s):  
Sol Alonso ◽  
Georgina Coldwell ◽  
Fernanda Duplancic ◽  
Valeria Mesa ◽  
Diego G. Lambas

Aims. With the aim of performing a suitable comparison of the internal process of galactic bars with respect to the external effect of interactions on driving gas toward the inner most region of the galaxies, we explored and compared the efficiency of both mechanisms on central nuclear activity in optically selected active galactic nuclei (AGNs) in spiral galaxies. Methods. We selected homogeneous samples of barred AGNs and active objects residing in pair systems, derived from the Sloan Digital Sky Survey (SDSS). In order to carry out a reliable comparison of both samples (AGNs in barred hosts in isolation and in galaxy pairs), we selected spiral AGN galaxies with similar distributions of redshift, magnitude, stellar mass, color and stellar age population from both catalogs. With the goal of providing an appropriate quantification of the influence of strong bars and interactions on nuclear activity, we also constructed a suitable control sample of unbarred spiral AGNs without a companion and with similar host properties to the other two samples. Results. We found that barred optically selected AGNs show an excess of nuclear activity (as derived from the Lum[OIII]) and accretion rate onto a central black hole (ℛ) with respect to AGNs in pairs. In addition, both samples show an excess of high values of Lum[OIII] and ℛ with respect to unbarred AGNs in the control sample. We also found that the fractions of AGNs with powerful nuclear activity and high accretion rates increase toward more massive hosts with bluer colors and younger stellar populations. Moreover, AGNs with bars exhibit a higher fraction of galaxies with powerful Lum[OIII] and efficient ℛ with respect to AGN galaxies inhabiting pair systems, in bins of different galaxy properties. Regarding AGNs belonging to pair systems, we found that the central nuclear activity is remarkably dependent on the galaxy pair companion features. The Lum[OIII] for AGNs in pairs is clearly enhanced when the galaxy companion exhibits a bright and more massive host with high metallicity, blue color, efficient star formation activity and young stellar population. The results of this work reveal an important capacity of both mechanisms, bars and interactions, to transport material towards the galaxy central regions. In this context, it should also be noted that the internal process of the bar is more efficient at improving the central nuclear activity in AGN objects than that corresponding to the external mechanism of the galaxy–galaxy interactions.


2020 ◽  
Vol 8 (4) ◽  
pp. 1408-1415

Despite the urgent need to accelerate the development of intensive forest management and reforestation technologies in Russia, the problem of creating progressive technologies and techniques to increase the efficiency of reforestation by seedlings and saplings of forest crops has not been completely resolved, which are serious challenges for accelerated and high-quality reforestation. Of particular concern is the lack of patented equipment competitive in the domestic and foreign markets for reforestation by seedlings and saplings of forest crops that can accelerate the creation of highly productive forests. To answer these challenges, it is proposed as a tool for the synthesis of patentable solutions that increase the efficiency of forest regeneration by seedlings and saplings of forest crops, to use the knowledge base formed on the basis of patent information search and the author’s methodology of functional, structural and technological analysis. A classification of the main areas of patenting in this area is proposed. The most characteristic patented objects of technologies and equipment that can be used as analogues and prototypes for the synthesis and patenting of new intellectual property for planting seedlings/saplings, as well as business entities patenting in this area, are identified. The effects (goals) for the achievement of which the technical solutions incorporated in the patents are directed are revealed. Using the generated knowledge base and the FSTA methodology, a synthesis of new patentable technical solutions has been carried out. Its features and some results are given on the example of several basic objects of machines and manual devices for planting seedlings/saplings. It is proved that the application of the proposed methodology to the selected object for improving the processes of planting seedlings/saplings is effective, which is confirmed by the development and patenting of fundamentally new technical solutions for equipping forest regeneration with seedlings and saplings of forest crops.


2020 ◽  
Author(s):  
Wade R. Roberts ◽  
Kala M. Downey ◽  
Elizabeth C. Ruck ◽  
Jesse C. Traller ◽  
Andrew J. Alverson

ABSTRACTThe diatom, Cyclotella cryptica, is a well-established experimental model for physiological studies and, more recently, biotechnology applications of diatoms. To further facilitate its use as a model diatom species, we report an improved reference genome assembly and annotation for C. cryptica strain CCMP332. We used a combination of long- and short-read sequencing to assemble a high-quality and contaminant-free genome. The genome is 171 Mb in size and consists of 662 scaffolds with a scaffold N50 of 494 kb. This represents a 176-fold decrease in scaffold number and 41-fold increase in scaffold N50 compared to the previous assembly. The genome contains 21,250 predicted genes, 75% of which were assigned putative functions. Repetitive DNA comprises 59% of the genome, and an improved classification of repetitive elements indicated that a historically steady accumulation of transposable elements has contributed to the relatively large size of the C. cryptica genome. The high-quality C. cryptica genome will serve as a valuable reference for ecological, genetic, and biotechnology studies of diatoms.Data available fromNCBI BioProjects PRJNA628076 and PRJNA589195


2020 ◽  
Vol 24 (4) ◽  
pp. 942-964
Author(s):  
Alexey S. Koshel

The article investigtes the powers and parliamentary procedures in the standing committees and commissions of several countries of Western Europe and Latin America. The author believes that one of the modern paradigms for the development of parliamentary democracy is to strengthen the role of standing committees in the work of parliament by transferring to the committee level a number of constitutional powers of parliaments. In this regard, the author clarifies approaches to the classification of the committee structure of parliaments and looks at committee parliamentary procedures in Italy, Germany, Greece, Portugal, Spain, Brazil and Argentina at the present stage. The author comes to certain conclusions regarding the paradigm of the committee parliamentary procedure, including further improvement of domestic constitutional-legal matter in the context of the ongoing development of parliamentary democracy in the Russian Federation.


Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Hakan Ay ◽  
Ethem M Arsava ◽  
Robert D. Brown ◽  
Steven J Kittner ◽  
Jin-Moo Lee ◽  
...  

Background and Purpose: NINDS Stroke Genetics Network (SiGN) is an international consortium of ischemic stroke studies that aims to generate high quality phenotype data to identify the genetic basis of ischemic stroke subtypes. The goal of this analysis is to characterize the etiopathogenetic basis of ischemic stroke in the consortium. Methods: This analysis included 16,954 subjects with imaging-confirmed ischemic stroke from 12 US studies and 11 studies from 8 European countries. 52 trained and certified adjudicators used the web-based Causative Classification of Stroke System for etiologic stroke classification through chart reviews to determine both phenotypic (abnormal test findings categorized in major etiologic groups without weighting towards the most likely cause in the presence of multiple etiologies) and causative subtypes in each subject. Classification reliability was assessed with blinded re-adjudication of 1509 randomly selected cases. Findings: The figure shows the distribution of etiologic categories. Overall, only 40% to 54% of cases with a given major ischemic stroke etiology (phenotypic subtype) were classified into the same final causative category with high confidence. There was good agreement for both causative (kappa 0·72, 95%CI:0·69-0·75) and phenotypic classifications (kappa 0·73, 95%CI:0·70-0·75). Conclusions: This study provides high quality data on etiologic stroke subtypes and demonstrates that etiologic subtypes can be determined with good reliability in studies that include investigators with different expertise and background, institutions with different stroke evaluation protocols and geographic location, and patient populations with different epidemiological characteristics. The discordance between phenotypic and causative stroke subtypes suggests that the presence of an abnormality in a stroke patient does not necessarily mean that it is the cause of stroke.


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