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Author Shi, P.; Chen, L.; Quinn, B.K.; Yu, K.; Miao, Q.; Guo, X.; Lian, M.; Gielis, J.; Niklas, K.J. pdf  url
doi  openurl
  Title A simple way to calculate the volume and surface area of avian eggs Type A1 Journal article
  Year 2023 Publication Annals of the New York Academy of Sciences Abbreviated Journal  
  Volume (down) 1524 Issue 1 Pages 118-131  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Egg geometry can be described using Preston's equation, which has seldom been used to calculate egg volume (V) and surface area (S) to explore S versus V scaling relationships. Herein, we provide an explicit re-expression of Preston's equation (designated as EPE) to calculate V and S, assuming that an egg is a solid of revolution. The side (longitudinal) profiles of 2221 eggs of six avian species were digitized, and the EPE was used to describe each egg profile. The volumes of 486 eggs from two avian species predicted by the EPE were compared with those obtained using water displacement in graduated cylinders. There was no significant difference in V using the two methods, which verified the utility of the EPE and the hypothesis that eggs are solids of revolution. The data also indicated that V is proportional to the product of egg length (L) and maximum width (W) squared. A 2/3-power scaling relationship between S and V for each species was observed, that is, S is proportional to (LW2)(2/3). These results can be extended to describe the shapes of the eggs of other species to study the evolution of avian (and perhaps reptilian) eggs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000975679400001 Publication Date 2023-04-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0077-8923; 1749-6632 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.2 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 5.2; 2023 IF: 4.706  
  Call Number UA @ admin @ c:irua:196724 Serial 8827  
Permanent link to this record
 

 
Author Shi, P.; Gielis, J.; Quinn, B.K.; Niklas, K.J.; Ratkowsky, D.A.; Schrader, J.; Ruan, H.; Wang, L.; Niinemets, Ü.; Niinennets, U. url  doi
openurl 
  Title ‘biogeom’ : an R package for simulating and fitting natural shapes Type A1 Journal article
  Year 2022 Publication Annals of the New York Academy of Sciences Abbreviated Journal Ann Ny Acad Sci  
  Volume (down) 1516 Issue 1 Pages 123-134  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Many natural objects exhibit radial or axial symmetry in a single plane. However, a universal tool for simulating and fitting the shapes of such objects is lacking. Herein, we present an R package called 'biogeom' that simulates and fits many shapes found in nature. The package incorporates novel universal parametric equations that generate the profiles of bird eggs, flowers, linear and lanceolate leaves, seeds, starfish, and tree-rings, and three growth-rate equations that generate the profiles of ovate leaves and the ontogenetic growth curves of animals and plants. 'biogeom' includes several empirical datasets comprising the boundary coordinates of bird eggs, fruits, lanceolate and ovate leaves, tree rings, seeds, and sea stars. The package can also be applied to other kinds of natural shapes similar to those in the datasets. In addition, the package includes sigmoid curves derived from the three growth-rate equations, which can be used to model animal and plant growth trajectories and predict the times associated with maximum growth rate. 'biogeom' can quantify the intra- or interspecific similarity of natural outlines, and it provides quantitative information of shape and ontogenetic modification of shape with important ecological and evolutionary implications for the growth and form of the living world.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000829772300001 Publication Date 2022-07-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0077-8923; 1749-6632 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.2 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 5.2  
  Call Number UA @ admin @ c:irua:189314 Serial 7131  
Permanent link to this record
 

 
Author Shi, P.; Gielis, J.; Niklas, K.J. pdf  url
doi  openurl
  Title Comparison of a universal (but complex) model for avian egg shape with a simpler model Type Editorial
  Year 2022 Publication Annals of the New York Academy of Sciences Abbreviated Journal Ann Ny Acad Sci  
  Volume (down) 1514 Issue 1 Pages 34-42  
  Keywords Editorial; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Recently, a universal equation by Narushin, Romanov, and Griffin (hereafter, the NRGE) was proposed to describe the shape of avian eggs. While NRGE can simulate the shape of spherical, ellipsoidal, ovoidal, and pyriform eggs, its predictions were not tested against actual data. Here, we tested the validity of the NRGE by fitting actual data of egg shapes and compared this with the predictions of our simpler model for egg shape (hereafter, the SGE). The eggs of nine bird species were sampled for this purpose. NRGE was found to fit the empirical data of egg shape well, but it did not define the egg length axis (i.e., the rotational symmetric axis), which significantly affected the prediction accuracy. The egg length axis under the NRGE is defined as the maximum distance between two points on the scanned perimeter of the egg's shape. In contrast, the SGE fitted the empirical data better, and had a smaller root-mean-square error than the NRGE for each of the nine eggs. Based on its mathematical simplicity and goodness-of-fit, the SGE appears to be a reliable and useful model for describing egg shape.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000803394100001 Publication Date 2022-06-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0077-8923; 1749-6632 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.2 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 5.2  
  Call Number UA @ admin @ c:irua:188470 Serial 7139  
Permanent link to this record
 

 
Author de Jong van Coevorden, C.M.; Gielis, J.; Caratelli, D. url  doi
openurl 
  Title Application of Gielis transformation to the design of metamaterial structures Type A1 Journal article
  Year 2018 Publication Journal of physics : conference series Abbreviated Journal  
  Volume (down) 963 Issue Pages Unsp 012008  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In this communication, the use of Gielis transformation to design more compact metamaterial unit cells is explored. For this purpose, transformed complementary split ring resonators and spiral resonators are coupled to micro-strip lines and theirbehaviour is investigated. The obtained results confirm that the useof the considered class of supershaped geometries enables the synthesis of very compact scalable microwave components.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000435022800008 Publication Date 2018-02-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6588; 1742-6596 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:150947 Serial 7475  
Permanent link to this record
 

 
Author Gielis, J.; Caratelli, D.; de Jong van Coevorden, M.; Ricci, P.E. doi  isbn
openurl 
  Title The common descent of biological shape description and special functions Type H1 Book chapter
  Year 2018 Publication Abbreviated Journal  
  Volume (down) 230 Issue Pages 119-131 T2 - Differential and difference equations  
  Keywords H1 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Gielis transformations, with their origin in botany, are used to define square waves and trigonometric functions of higher order. They are rewritten in terms of Chebyshev polynomials. The origin of both, a uniform descriptor and the origin of orthogonal polynomials, can be traced back to a letter of Guido Grandi to Leibniz in 1713 on the mathematical description of the shape of flowers. In this way geometrical description and analytical tools are seamlessly combined.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000451375900010 Publication Date 2018-05-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-3-319-75646-2; 2194-1009; 978-3-319-75647-9; 978-3-319-75646-2 Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:150949 Serial 7685  
Permanent link to this record
 

 
Author Caratelli, D.; Gielis, J.; Ricci, P.E.; Tavkhelidze, I. pdf  doi
openurl 
  Title Some properties of “bulky” links, generated by Generalized Möbius Listing's bodies GML4n Type A2 Journal article
  Year 2016 Publication Journal of mathematical sciences Abbreviated Journal  
  Volume (down) 216 Issue 4 Pages 509-518  
  Keywords A2 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In the present paper, we consider the bulky knots and bulky links that appear after cutting of generalized MöbiusListing GML 4 n bodies (with corresponding radial cross sections square) along different generalized MöbiusListing surfaces GML 2 n situated in it. The aim of this article is to examine the number and geometric structure of independent objects that appear after such a cutting process of GML 4 n bodies. In most cases, we are able to count the indices of the resulting mathematical objects according to the known tabulation for knots and links of small complexity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2016-06-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1072-3374; 1573-8795 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:133948 Serial 8554  
Permanent link to this record
 

 
Author Gielis, J.; Tavkhelidze, I.; Ricci, P.E. pdf  doi
openurl 
  Title About “bulky” links generated by generalized Möbius-Listing bodies GML2n Type A2 Journal article
  Year 2013 Publication Journal of mathematical sciences Abbreviated Journal  
  Volume (down) 193 Issue 3 Pages 449-460  
  Keywords A2 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In this paper, we consider the bulky knots and bulky links, which appear after cutting of a Generalized MöbiusListing GMLn2 body (with the radial cross section a convex plane 2-symmetric figure with two vertices) along a different Generalized MöbiusListing surfaces GMLn2 situated in it. The aim of this report is to investigate the number and geometric structure of the independent objects that appear after such a cutting process of GMLn2 bodies. In most cases we are able to count the indices of the resulting mathematical objects according to the known classification for the standard knots and links.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2013-08-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1072-3374; 1573-8795 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:110953 Serial 7404  
Permanent link to this record
 

 
Author Gielis, J. pdf  doi
openurl 
  Title Double helix of phyllotaxis : analysis of the geometric model of plant morphogenesis, by Boris Rozin Type Review
  Year 2021 Publication Quarterly Review Of Biology Abbreviated Journal Q Rev Biol  
  Volume (down) 96 Issue 2 Pages 139-140  
  Keywords Review; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2021-05-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0033-5770; 1539-7718 ISBN Additional Links UA library record  
  Impact Factor 4.25 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 4.25  
  Call Number UA @ admin @ c:irua:178829 Serial 7824  
Permanent link to this record
 

 
Author Mescia, L.; Chiapperino, M.A.; Bia, P.; Gielis, J.; Caratelli, D. pdf  doi
openurl 
  Title Modeling of electroporation induced by pulsed electric fields in irregularly shaped cells Type A1 Journal article
  Year 2018 Publication IEEE transactions on biomedical engineering Abbreviated Journal  
  Volume (down) 65 Issue 2 Pages 414-423  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract During the past decades, the poration of cell membrane induced by pulsed electric fields has been widely investigated. Since the basic mechanisms of this process have not yet been fully clarified, many research activities are focused on the development of suitable theoretical and numerical models. To this end, a nonlinear, nonlocal, dispersive, and space-time numerical algorithm has been developed and adopted to evaluate the transmembrane voltage and pore density along the perimeter of realistic irregularly shaped cells. The presented model is based on the Maxwell's equations and the asymptotic Smoluchowski's equation describing the pore dynamics. The dielectric dispersion of the media forming the cell has been modeled by using a general multirelaxation Debye-based formulation. The irregular shape of the cell is described by using the Gielis' superformula. Different test cases pertaining to red blood cells, muscular cells, cell in mitosis phase, and cancer-like cell have been investigated. For each type of cell, the influence of the relevant shape, the dielectric properties, and the external electric pulse characteristics on the electroporation process has been analyzed. The numerical results demonstrate that the proposed model is an efficient numerical tool to study the electroporation problem in arbitrary-shaped cells.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000422914700018 Publication Date 2017-11-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018-9294 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:148417 Serial 8264  
Permanent link to this record
 

 
Author Li, Y.; Quinn, B.K.; Niinemets, Ü.; Schrader, J.; Gielis, J.; Liu, M.; Shi, P. url  doi
openurl 
  Title Ellipticalness index : a simple measure of the complexity of oval leaf shape Type A1 Journal article
  Year 2022 Publication Pakistan journal of botany : An official publication of pakistan botanical society Abbreviated Journal Pak J Bot  
  Volume (down) 54 Issue 6 Pages 1-8  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Plants have diverse leaf shapes that have evolved to adapt to the environments they have experienced over their evolutionary history. Leaf shape and leaf size can greatly influence the growth rate, competitive ability, and productivity of plants. However, researchers have long struggled to decide how to properly quantify the complexity of leaf shape. Prior studies recommended the leaf roundness index (RI = 4πA/P2) or dissection index (DI = ), where P is leaf perimeter and A is leaf area. However, these two indices merely measure the extent of the deviation of leaf shape from a circle, which is usually invalid as leaves are seldom circular. In this study, we proposed a simple measure, named the ellipticalness index (EI), for quantifying the complexity of leaf shape based on the hypothesis that the shape of any oval leaf can be regarded as a variation from a standard ellipse. 2220 leaves from nine species of Magnoliaceae were sampled to check the validity of the EI. We also tested the validity of the Montgomery equation (ME), which assumes a proportional relationship between leaf area and the product of leaf length and width, because the EI actually comes from the proportionality coefficient of the ME. We also compared the ME with five other models of leaf area. The ME was found to be the best model for calculating leaf area based on consideration of the trade-off between model fit vs. complexity, which strongly supported the robustness of the EI for describing oval leaf shape. The new index can account for both leaf shape and size, and we conclude that it is a promising method for quantifying and comparing oval leaf shapes across species in future studies.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000814279700028 Publication Date 2022-05-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-3321 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.2 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 1.2  
  Call Number UA @ admin @ c:irua:188469 Serial 7153  
Permanent link to this record
 

 
Author Gielis, J. openurl 
  Title Er bestaan geen absurde, irrationele, onregelmatige of onderling niet-onmeetbare meetkundige getallen Type A2 Journal article
  Year 2021 Publication Wiskunde en onderwijs Abbreviated Journal  
  Volume (down) 47 Issue 188 Pages 23-33  
  Keywords A2 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2032-0485 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:183083 Serial 7934  
Permanent link to this record
 

 
Author Fougerolle, Y.D.; Truchetet, F.; Demonceaux, C.; Gielis, J. pdf  doi
openurl 
  Title A robust evolutionary algorithm for the recovery of rational Gielis curves Type A1 Journal article
  Year 2013 Publication Pattern recognition Abbreviated Journal  
  Volume (down) 46 Issue 8 Pages 2078-2091  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Gielis curves (GC) can represent a wide range of shapes and patterns ranging from star shapes to symmetric and asymmetric polygons, and even self intersecting curves. Such patterns appear in natural objects or phenomena, such as flowers, crystals, pollen structures, animals, or even wave propagation. Gielis curves and surfaces are an extension of Lamé curves and surfaces (superquadrics) which have benefited in the last two decades of extensive researches to retrieve their parameters from various data types, such as range images, 2D and 3D point clouds, etc. Unfortunately, the most efficient techniques for superquadrics recovery, based on deterministic methods, cannot directly be adapted to Gielis curves. Indeed, the different nature of their parameters forbids the use of a unified gradient descent approach, which requires initial pre-processings, such as the symmetry detection, and a reliable pose and scale estimation. Furthermore, even the most recent algorithms in the literature remain extremely sensitive to initialization and often fall into local minima in the presence of large missing data. We present a simple evolutionary algorithm which overcomes most of these issues and unifies all of the required operations into a single though efficient approach. The key ideas in this paper are the replacement of the potential fields used for the cost function (closed form) by the shortest Euclidean distance (SED, iterative approach), the construction of cost functions which minimize the shortest distance as well as the curve length using R-functions, and slight modifications of the evolutionary operators. We show that the proposed cost function based on SED and R-function offers the best compromise in terms of accuracy, robustness to noise, and missing data.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000317944800002 Publication Date 2013-01-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-3203 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:107181 Serial 8485  
Permanent link to this record
 

 
Author Vermander, C.; De Wael, J.; Gielis, J. pdf  openurl
  Title De kleine boerderij : twee bijzondere tuinkamers Type A2 Journal article
  Year 2019 Publication Groencontact Abbreviated Journal  
  Volume (down) 45 Issue 5 Pages 14-19  
  Keywords A2 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1374-4631 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:164895 Serial 8142  
Permanent link to this record
 

 
Author Chiapperino, M.A.; Bia, P.; Caratelli, D.; Gielis, J.; Mescia, L.; Dermol-Cerne, J.; Miklavcic, D. pdf  doi
openurl 
  Title Nonlinear dispersive model of electroporation for irregular nucleated cells Type A1 Journal article
  Year 2019 Publication Bioelectromagnetics Abbreviated Journal  
  Volume (down) 40 Issue 5 Pages 331-342  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In this work, the electroporation phenomenon induced by pulsed electric field on different nucleated biological cells is studied. A nonlinear, non-local, dispersive, and space-time multiphysics model based on Maxwell's and asymptotic Smoluchowski's equations has been developed to calculate the transmembrane voltage and pore density on both plasma and nuclear membrane perimeters. The irregular cell shape has been modeled by incorporating in the numerical algorithm the analytical functions pertaining to Gielis curves. The dielectric dispersion of the cell media has been modeled considering the multi-relaxation Debye-based relationship. Two different irregular nucleated cells have been investigated and their response has been studied applying both the dispersive and non-dispersive models. By a comparison of the obtained results, differences can be highlighted confirming the need to make use of the dispersive model to effectively investigate the cell response in terms of transmembrane voltages, pore densities, and electroporation opening angle, especially when irregular cell shapes and short electric pulses are considered. Bioelectromagnetics. 2019;40:331-342. (c) 2019 Wiley Periodicals, Inc.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000472568200004 Publication Date 2019-06-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0197-8462 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:161282 Serial 8315  
Permanent link to this record
 

 
Author Gielis, J.; Grigolia, R. url  openurl
  Title Lamé curves and Rvachev's R-functions Type A3 Journal article
  Year 2022 Publication Sn – 1512-0066 Abbreviated Journal  
  Volume (down) 37 Issue Pages 1-4  
  Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Gielis transformations are a generalization of Lame curves. To combine domains, we can make use of the natural alliance between Lame's work and Rvachev's R-functions. A logical next step is the extension to n-valued logic dening dierent partitions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:189316 Serial 7178  
Permanent link to this record
 

 
Author Lian, M.; Shi, P.; Zhang, L.; Yao, W.; Gielis, J.; Niklas, K.J. pdf  url
doi  openurl
  Title A generalized performance equation and its application in measuring the Gini index of leaf size inequality Type A1 Journal article
  Year 2023 Publication Trees: structure and function Abbreviated Journal  
  Volume (down) 37 Issue Pages 1555-1565  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The goal of this study is to provide a rigorous tool to quantify the inequality of the leaf size distribution of an individual plant, thereby serving as a reference trait for quantifying plant adaptations to local environmental conditions. The tool to be presented and tested employs three components: (1) a performance equation (PE), which can produce flexible asymmetrical and symmetrical bell-shaped curves, (2) the Lorenz curve (i.e., the cumulative proportion of leaf size vs. the cumulative proportion of number of leaves), which is the basis for calculating, and (3) the Gini index, which measures the inequality of leaf size distribution. We sampled 12 individual plants of a dwarf bamboo and measured the area and dry mass of each leaf of each plant. We then developed a generalized performance equation (GPE) of which the PE is a special case and fitted the Lorenz curve to leaf size distribution using the GPE and PE. The GPE performed better than the PE in fitting the Lorenz curve. We compared the Gini index of leaf area distribution with that of leaf dry mass distribution and found that there was a significant difference between the two indices that might emerge from the scaling relationship between leaf dry mass and area. Nevertheless, there was a strong correlation between the two Gini indices (r2 = 0.9846). This study provides a promising tool based on the GPE for quantifying the inequality of leaf size distributions across individual plants and can be used to quantify plant adaptations to local environmental conditions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001069570200001 Publication Date 2023-08-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0931-1890; 1432-2285 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.3 Times cited Open Access Not_Open_Access: Available from 26.02.2024  
  Notes Approved Most recent IF: 2.3; 2023 IF: 1.842  
  Call Number UA @ admin @ c:irua:199562 Serial 8874  
Permanent link to this record
 

 
Author De Tommasi, E.; Gielis, J.; Rogato, A. pdf  url
doi  openurl
  Title Diatom frustule morphogenesis and function : a multidisciplinary survey Type A1 Journal article
  Year 2017 Publication Marine Genomics Abbreviated Journal  
  Volume (down) 35 Issue Pages 1-18  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Diatoms represent the major component of phytoplankton and are responsible for about 2025% of global primary production. Hundreds of millions of years of evolution led to tens of thousands of species differing in dimensions and morphologies. In particular, diatom porous silica cell walls, the frustules, are characterized by an extraordinary, species-specific diversity. It is of great interest, among the marine biologists and geneticists community, to shed light on the origin and evolutionary advantage of this variability of dimensions, geometries and pore distributions. In the present article the main reported data related to frustule morphogenesis and functionalities with contributions from fundamental biology, genetics, mathematics, geometry and physics are reviewed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000412957700001 Publication Date 2017-07-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1874-7787 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:144546 Serial 7807  
Permanent link to this record
 

 
Author Zhang, L.; Quinn, B.K.; Hui, C.; Lian, M.; Gielis, J.; Gao, J.; Shi, P. url  doi
openurl 
  Title New indices to balance α-diversity against tree size inequality Type A1 Journal article
  Year 2024 Publication Journal of forestry research Abbreviated Journal  
  Volume (down) 35 Issue 1 Pages 31-39  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The number and composition of species in a community can be quantified with alpha-diversity indices, including species richness (R), Simpson's index (D), and the Shannon-Wiener index (HGREEK TONOS). In forest communities, there are large variations in tree size among species and individuals of the same species, which result in differences in ecological processes and ecosystem functions. However, tree size inequality (TSI) has been largely neglected in studies using the available diversity indices. The TSI in the diameter at breast height (DBH) data for each of 999 20 m x 20 m forest census quadrats was quantified using the Gini index (GI), a measure of the inequality of size distribution. The generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBH and the cumulative proportion of number of trees per quadrat. We also examined the relationships of alpha-diversity indices with the GI using correlation tests. The generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBH distributions, with most root-mean-square errors (990 out of 999 quadrats) being < 0.0030. There were significant positive correlations between each of three alpha-diversity indices (i.e., R, D, and H') and the GI. Nevertheless, the total abundance of trees in each quadrat did not significantly influence the GI. This means that the TSI increased with increasing species diversity. Thus, two new indices are proposed that can balance alpha-diversity against the extent of TSI in the community: (1 – GI) x D, and (1 – GI) x H'. These new indices were significantly correlated with the original D and HGREEK TONOS, and did not increase the extent of variation within each group of indices. This study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities, especially in the face of cumulative species loss under global climate change.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001131698000001 Publication Date 2023-12-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1007-662x; 1993-0607 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:201972 Serial 9061  
Permanent link to this record
 

 
Author Tavkhelidze, I.; Gielis, J.; Pinelas, S. file  openurl
  Title About some methods of analytic representation and classification of a wide set of geometric figures with “complex” configuration Type A3 Journal article
  Year 2020 Publication Sn – 1512-0066 Abbreviated Journal  
  Volume (down) 34 Issue Pages 81-84  
  Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:174475 Serial 7406  
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Author Gielis, J.; Tavkhelidze, I. file  openurl
  Title The Mӧbius phenomenon in Generalized Mӧbius-Listing bodies with cross sections of odd and even polygons Type A3 Journal article
  Year 2020 Publication Sn – 1512-0066 Abbreviated Journal  
  Volume (down) 34 Issue Pages 23-26  
  Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:174474 Serial 8257  
Permanent link to this record
 

 
Author Gielis, J. url  doi
openurl 
  Title Fred Van Oystaeyen : Time hybrids: a new generic theory of reality Type Review
  Year 2023 Publication Symmetry, Culture and Science Abbreviated Journal  
  Volume (down) 34 Issue 3 Pages 347-351  
  Keywords Review; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:199538 Serial 8871  
Permanent link to this record
 

 
Author Gielis, J. url  doi
openurl 
  Title Simon Stevin as a central figure in the development of abstract algebra and generic programming Type A1 Journal article
  Year 2023 Publication Symmetry : culture and science Abbreviated Journal  
  Volume (down) 34 Issue 2 Pages 155-168  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Simon Stevin (1548-1620) is mainly known for the decimal system and his Clootkrans proof. His influence is also profound in infinitesimal calculus, mechanics, and even in abstract algebra and today’s conception of polynomials, algorithms, and generic programming. Here we review his influence as assessed in generic programming. According to Dr. Stepanov, one of the most influential researchers in generic programming, Stevin’s work on polynomials can be regarded as the essence of generic programming: an algorithm from one domain can be applied in another similar domain.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001068714100003 Publication Date 2023-07-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0865-4824 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access Not_Open_Access: Available from 08.02.2024  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:198000 Serial 8929  
Permanent link to this record
 

 
Author Li, Y.; Niklas, K.J.; Gielis, J.; Niinemets, Ü.; Schrader, J.; Wang, R.; Shi, P. url  doi
openurl 
  Title An elliptical blade is not a true ellipse, but a superellipse : evidence from two Michelia species Type A1 Journal article
  Year 2022 Publication Journal of forestry research Abbreviated Journal J Forestry Res  
  Volume (down) 33 Issue 4 Pages 1341-1348  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The shape of leaf laminae exhibits considerable diversity and complexity that reflects adaptations to environmental factors such as ambient light and precipitation as well as phyletic legacy. Many leaves appear to be elliptical which may represent a ‘default’ developmental condition. However, whether their geometry truly conforms to the ellipse equation (EE), i.e., (x/a)2 + (y/b)2 = 1, remains conjectural. One alternative is described by the superellipse equation (SE), a generalized version of EE, i.e., |x/a|n +|y/b|n = 1. To test the efficacy of EE versus SE to describe leaf geometry, the leaf shapes of two Michelia species (i.e., M. cavaleriei var. platypetala, and M. maudiae), were investigated using 60 leaves from each species. Analysis shows that the majority of leaves (118 out of 120) had adjusted root-mean-square errors of < 0.05 for the nonlinear fitting of SE to leaf geometry, i.e., the mean absolute deviation from the polar point to leaf marginal points was smaller than 5% of the radius of a hypothesized circle with its area equaling leaf area. The estimates of n for the two species were ˂ 2, indicating that all sampled leaves conformed to SE and not to EE. This study confirms the existence of SE in leaves, linking this to its potential functional advantages, particularly the possible influence of leaf shape on hydraulic conductance.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000695118600001 Publication Date 2021-09-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1007-662x; 1993-0607 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3  
  Call Number UA @ admin @ c:irua:180967 Serial 7152  
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Author Shi, P.; Liu, M.; Ratkowsky, D.A.; Gielis, J.; Su, J.; Yu, X.; Wang, P.; Zhang, L.; Lin, Z.; Schrader, J. pdf  url
doi  openurl
  Title Leaf area-length allometry and its implications in leaf shape evolution Type A1 Journal article
  Year 2019 Publication Trees: structure and function Abbreviated Journal  
  Volume (down) 33 Issue 4 Pages 1073-1085  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract According to Thompson’s principle of similarity, the area of an object should be proportional to its length squared. However, leaf area–length data of some plants have been demonstrated not to follow the principle of similarity. We explore the reasons why the leaf area–length allometry deviates from the principle of similarity and examine whether there is a general model describing the relationship among leaf area, width and length. We sampled more than 11,800 leaves from six classes of woody and herbaceous plants and tested the leaf area–length allometry. We compared six mathematical models based on root-mean-square error as the measure of goodness-of-fit. The best supported model described a proportional relationship between leaf area and the product of leaf width and length (i.e., the Montgomery model). We found that the extent to which the leaf area–length allometry deviates from the principle of similarity depends upon the extent of variation of the ratio of leaf width to length. Estimates of the parameter of the Montgomery model ranged between 1/2, which corresponds to a triangular leaf with leaf length as its height and leaf width as its base, and π/4, which corresponds to an elliptical leaf with leaf length as its major axis and leaf width as its minor axis, for the six classes of plants. The narrow range in practice of the Montgomery parameter implies an evolutionary stability for the leaf area of large-leaved plants despite the fact that leaf shapes of these plants are rather different.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000475992600010 Publication Date 2019-04-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0931-1890; 1432-2285 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:159970 Serial 8170  
Permanent link to this record
 

 
Author Tavkhelidze, I.; Gielis, J. openurl 
  Title Structure of the dm knives and process of cutting of GML(man) or GRT(man) bodies Type A3 Journal article
  Year 2019 Publication Sn – 1512-0066 Abbreviated Journal  
  Volume (down) 33 Issue Pages  
  Keywords A3 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:164897 Serial 8588  
Permanent link to this record
 

 
Author Chapman, D.; Gielis, J. doi  openurl
  Title Gielis transformations for the audiovisual geometry database Type A1 Journal article
  Year 2021 Publication Symmetry : culture and science Abbreviated Journal  
  Volume (down) 32 Issue 2 Pages 177-180  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract This publication introduces the audiovisual geometry database with Gielis transformations as initial records for a prototype of the database. A concise overview is given of the rationale behind the database and studying wave phenomena with Gielis transformations. First results on a form of timbral polyphony observed in Gielis curves and future work are briefly discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2021-07-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0865-4824 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:180965 Serial 8004  
Permanent link to this record
 

 
Author Gielis, J. pdf  url
doi  openurl
  Title Phi-bonacci in Ancient Greece Type A1 Journal article
  Year 2021 Publication Symmetry : culture and science Abbreviated Journal  
  Volume (down) 32 Issue 1 Pages 25-40  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Fibonacci numbers are a very popular subject in mathematics, culture and science. A major open question is why the ancient Greeks overlooked this series, while they were very familiar with the golden mean and division in extreme and mean ratio. Furthermore, they could compute the square root of five to a high degree of precision using Theon 's ladder. This fact is based on tables built with side and diagonal numbers, and it is a simple and incredibly efficient method to compute roots of integers, though it is little known even now among most of the experts. The biologist D 'Arcy Wentworth Thompson showed that the same method could be used to generate the Fibonacci series using a simple shift in the computation of the tables. He argues, quite convincingly, that the ancient Greeks could not have overlooked this. Actually, the same method can be used to generate all possible regular phyllotaxis patterns.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000643822700002 Publication Date 2021-03-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0865-4824 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:178322 Serial 8376  
Permanent link to this record
 

 
Author Tavkhelidze, I.; Gielis, J. pdf  openurl
  Title The process of cutting GMLmn bodies with dm-knives Type A3 Journal article
  Year 2018 Publication Sn – 1512-0066 Abbreviated Journal  
  Volume (down) 32 Issue Pages 67-70  
  Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:159971 Serial 8417  
Permanent link to this record
 

 
Author Gielis, J.; Brasili, S. doi  openurl
  Title The apeirogon and dual numbers Type A1 Journal article
  Year 2021 Publication Symmetry : culture and science Abbreviated Journal  
  Volume (down) 32 Issue 2 Pages 157-160  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The richness, diversity, connection, depth and pleasure of studying symmetry continue to open doors. Here we report a connection between Coxeter's Apeirogon and the geometry associated with pictorial space, parabolic rotation and dual numbers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000670122100011 Publication Date 2021-07-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0865-4824 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:179759 Serial 8652  
Permanent link to this record
 

 
Author Tian, F.; Wang, Y.; Sandhu, H.S.; Gielis, J.; Shi, P. pdf  url
doi  openurl
  Title Comparison of seed morphology of two ginkgo cultivars Type A1 Journal article
  Year 2020 Publication Journal Of Forestry Research Abbreviated Journal J Forestry Res  
  Volume (down) 31 Issue 3 Pages 751-758  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Ginkgo biloba L. is a precious relic tree species with important economic value. Seeds, as a vital reproductive organ of plants, can be used to distinguish cultivars of the species. We chose 400 seeds from two cultivars of ginkgo (Fozhi and Maling; 200 seeds for each cultivar) as the study material and used the Gielis equation to fit the projected shape of these seeds. The coefficients of variation (CV) in root mean squared errors (RMSE) obtained from the fitted data were used to compare the level of inter-cultivar variations in seed shape. We also used the covariance analysis to compare the allometric relationships between seed weights and projected areas of these two cultivars. The Gielis equation fitted well the seed shapes of two ginkgo cultivars. The lower CV in RMSE of cultivar Fozhi than Maling indicated a less symmetrical seed shape in the latter than the former. The bootstrap percentile method showed that the seed shape differences between the two cultivars were significant. However, there was no significant difference in the exponents between the seed weights and the projected areas of these two cultivars. Overall, the significant differences in shapes between the seeds of two ginkgo cultivars were well explained by the Gielis equation; this model can be further extended to compare morphological differences in other ginkgo cultivars, and even for plant seeds or animal eggs that have similar oval shapes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000529367600005 Publication Date 2018-07-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1007-662x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3 Times cited 3 Open Access  
  Notes ; ; Approved Most recent IF: 3; 2020 IF: 0.774  
  Call Number UA @ admin @ c:irua:154987 Serial 6474  
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