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Author Li, Q.; Niklas, K.J.J.; Niinemets, U.; Zhang, L.; Yu, K.; Gielis, J.; Gao, J.; Shi, P.
Title Stomatal shape described by a superellipse in four Magnoliaceae species Type A1 Journal article
Year 2023 Publication Botany letters Abbreviated Journal
Volume Issue Pages 1-9
Keywords (up) A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Stomata are essential for the exchange of water vapour and atmospheric gases between vascular plants and their external environments. The stomatal geometries of many plants appear to be elliptical. However, prior studies have not tested whether this is a mathematical reality, particularly since many natural shapes that appear to be ellipses are superellipses with greater or smaller edge curvature than predicted for an ellipse. Compared with the ellipse equation, the superellipse equation includes an additional parameter that allows generation of a larger range of shapes. We randomly selected 240 stomata from each of four Magnoliaceae species to test whether the stomatal geometries are superellipses or ellipses. The stomatal geometries for most stomata (943/960) were found to be described better using the superellipse equation. The traditional “elliptical stomata hypothesis” resulted in an underestimation of the area of stomata, whereas the superellipse equation accurately predicted stomatal area. This finding has important implications for the estimation of stomatal area in studies looking at stomatal shape, geometry, and function.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001024190300001 Publication Date 2023-07-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2381-8107; 2381-8115 ISBN Additional Links UA library record; WoS full record
Impact Factor 1.5 Times cited Open Access Not_Open_Access: Available from 12.01.2024
Notes Approved Most recent IF: 1.5; 2023 IF: NA
Call Number UA @ admin @ c:irua:197847 Serial 8935
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Author Gielis, J.; Caratelli, D.; Shi, P.; Ricci, P.E.
Title A note on spirals and curvature Type A1 Journal article
Year 2020 Publication Growth and form Abbreviated Journal
Volume 1 Issue 1 Pages 1-8
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Starting from logarithmic, sinusoidal and power spirals, it is shown how these spirals are connected directly with Chebyshev polynomials, Lamé curves, with allometry and Antonelli-metrics in Finsler geometry. Curvature is a crucial concept in geometry both for closed curves and equiangular spirals, and allowed Dillen to give a general definition of spirals. Many natural shapes can be described as a combination of one of two basic shapes in nature—circle and spiral—with Gielis transformations. Using this idea, shape description itself is used to develop a novel approach to anisotropic curvature in nature. Various examples are discussed, including fusion in flowers and its connection to the recently described pseudo-Chebyshev functions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2020-02-23
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:167061 Serial 6569
Permanent link to this record
 
 
Author Dattoli, G.; Di Palma, E.; Gielis, J.; Licciardi, S.
Title Parabolic trigonometry Type A1 Journal article
Year 2020 Publication International journal of applied and computational mathematics Abbreviated Journal
Volume 6 Issue 2 Pages 37
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2020-03-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2349-5103 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:167049 Serial 6578
Permanent link to this record
 
 
Author Li, Y.; Niklas, K.J.; Gielis, J.; Niinemets, Ü.; Schrader, J.; Wang, R.; Shi, P.
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 33 Issue 4 Pages 1341-1348
Keywords (up) 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 Li, Y.; Quinn, B.K.; Niinemets, Ü.; Schrader, J.; Gielis, J.; Liu, M.; Shi, P.
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 54 Issue 6 Pages 1-8
Keywords (up) 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.; Shi, P.; Caratelli, D.
Title Universal equations : a fresh perspective Type A1 Journal article
Year 2022 Publication Growth and Form Abbreviated Journal
Volume Issue Pages
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract A uniform description of natural shapes and phenomena is an important goal in science. Such description should check some basic principles, related to 1) the complexity of the model, 2) how well its fits real objects, phenomena and data, and 3) ia direct connection with optimization principles and the calculus of variations. In this article, we present nine principles, three for each group, and we compare some models with a claim to universality. It is also shown that Gielis Transformations and power laws have a common origin in conic sections
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:189317 Serial 7224
Permanent link to this record
 
 
Author Yao, W.; Niinemets, Ü.; Yao, W.; Gielis, J.; Schrader, J.; Yu, K.; Shi, P.
Title Comparison of two simplified versions of the Gielis equation for describing the shape of bamboo leaves Type A1 Journal article
Year 2022 Publication Plants Abbreviated Journal
Volume 11 Issue 22 Pages 3058-11
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Bamboo is an important component in subtropical and tropical forest communities. The plant has characteristic long lanceolate leaves with parallel venation. Prior studies have shown that the leaf shapes of this plant group can be well described by a simplified version (referred to as SGE-1) of the Gielis equation, a polar coordinate equation extended from the superellipse equation. SGE-1 with only two model parameters is less complex than the original Gielis equation with six parameters. Previous studies have seldom tested whether other simplified versions of the Gielis equation are superior to SGE-1 in fitting empirical leaf shape data. In the present study, we compared a three-parameter Gielis equation (referred to as SGE-2) with the two-parameter SGE-1 using the leaf boundary coordinate data of six bamboo species within the same genus that have representative long lanceolate leaves, with >300 leaves for each species. We sampled 2000 data points at approximately equidistant locations on the boundary of each leaf, and estimated the parameters for the two models. The root–mean–square error (RMSE) between the observed and predicted radii from the polar point to data points on the boundary of each leaf was used as a measure of the model goodness of fit, and the mean percent error between the RMSEs from fitting SGE-1 and SGE-2 was used to examine whether the introduction of an additional parameter in SGE-1 remarkably improves the model’s fitting. We found that the RMSE value of SGE-2 was always smaller than that of SGE-1. The mean percent errors among the two models ranged from 7.5% to 20% across the six species. These results indicate that SGE-2 is superior to SGE-1 and should be used in fitting leaf shapes. We argue that the results of the current study can be potentially extended to other lanceolate leaf shapes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000887783400001 Publication Date 2022-11-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2223-7747 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:191859 Serial 7289
Permanent link to this record
 
 
Author Shi, P.; Ratkowsky, D.A.; Li, Y.; Zhang, L.; Lin, S.; Gielis, J.
Title A general leaf area geometric formula exists for plants evidence from the simplified Gielis equation Type A1 Journal article
Year 2018 Publication Forests (19994907) Abbreviated Journal
Volume 9 Issue 11 Pages 714
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Plant leaves exhibit diverse shapes that enable them to utilize a light resource maximally. If there were a general parametric model that could be used to calculate leaf area for different leaf shapes, it would help to elucidate the adaptive evolutional link among plants with the same or similar leaf shapes. We propose a simplified version of the original Gielis equation (SGE), which was developed to describe a variety of object shapes ranging from a droplet to an arbitrary polygon. We used this equation to fit the leaf profiles of 53 species (among which, 48 bamboo plants, 5 woody plants, and 10 geographical populations of a woody plant), totaling 3310 leaves. A third parameter (namely, the floating ratio c in leaf length) was introduced to account for the case when the theoretical leaf length deviates from the observed leaf length. For most datasets, the estimates of c were greater than zero but less than 10%, indicating that the leaf length predicted by the SGE was usually smaller than the actual length. However, the predicted leaf areas approximated their actual values after considering the floating ratios in leaf length. For most datasets, the mean percent errors of leaf areas were lower than 6%, except for a pooled dataset with 42 bamboo species. For the elliptical, lanceolate, linear, obovate, and ovate shapes, although the SGE did not fit the leaf edge perfectly, after adjusting the parameter c, there were small deviations of the predicted leaf areas from the actual values. This illustrates that leaves with different shapes might have similar functional features for photosynthesis, since the leaf areas can be described by the same equation. The anisotropy expressed as a difference in leaf shape for some plants might be an adaptive response to enable them to adapt to different habitats.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000451310300054 Publication Date 2018-11-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1999-4907 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:156324 Serial 7389
Permanent link to this record
 
 
Author Shi, P.; Yu, K.; Niinemets, Ü.; Gielis, J.
Title Can leaf shape be represented by the ratio of leaf width to length? Evidence from nine species of Magnolia and Michelia (Magnoliaceae) Type A1 Journal article
Year 2021 Publication Forests Abbreviated Journal Forests
Volume 12 Issue 1 Pages 41
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Leaf shape is closely related to economics of leaf support and leaf functions, including light interception, water use, and CO2 uptake, so correct quantification of leaf shape is helpful for studies of leaf structure/function relationships. There are some extant indices for quantifying leaf shape, including the leaf width/length ratio (W/L), leaf shape fractal dimension (FD), leaf dissection index, leaf roundness index, standardized bilateral symmetrical index, etc. W/L ratio is the simplest to calculate, and recent studies have shown the importance of the W/L ratio in explaining the scaling exponent of leaf dry mass vs. leaf surface area and that of leaf surface area vs. leaf length. Nevertheless, whether the W/L ratio could reflect sufficient geometrical information of leaf shape has been not tested. The FD might be the most accurate measure for the complexity of leaf shape because it can characterize the extent of the self-similarity and other planar geometrical features of leaf shape. However, it is unknown how strongly different indices of leaf shape complexity correlate with each other, especially whether W/L ratio and FD are highly correlated. In this study, the leaves of nine Magnoliaceae species (>140 leaves for each species) were chosen for the study. We calculated the FD value for each leaf using the box-counting approach, and measured leaf fresh mass, surface area, perimeter, length, and width. We found that FD is significantly correlated to the W/L ratio and leaf length. However, the correlation between FD and the W/L ratio was far stronger than that between FD and leaf length for each of the nine species. There were no strong correlations between FD and other leaf characteristics, including leaf area, ratio of leaf perimeter to area, fresh mass, ratio of leaf fresh mass to area, and leaf roundness index. Given the strong correlation between FD and W/L, we suggest that the simpler index, W/L ratio, can provide sufficient information of leaf shape for similarly-shaped leaves. Future studies are needed to characterize the relationships among FD and W/L in leaves with strongly varying shape, e.g., in highly dissected leaves.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000611074700001 Publication Date 2020-12-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1999-4907 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.951 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 1.951
Call Number UA @ admin @ c:irua:174473 Serial 7572
Permanent link to this record
 
 
Author Caratelli, D.; Gielis, J.; Ricci, P.E.
Title Fourier-like solution of the Dirichlet problem for the Laplace Equation in k-type Gielis domains Type A1 Journal article
Year 2011 Publication Journal of pure and applied mathematics : advances and applications Abbreviated Journal
Volume 5 Issue 2 Pages 99-111
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The interior and exterior Dirichlet problems for the Laplace equation in k-type Gielis domains are analytically addressed by using a suitable Fourier-like technique. A dedicated numerical procedure based on the computer-aided algebra tool Mathematica© is developed in order to validate the proposed approach. In this way, highly accurate approximations of the solution, featuring properties similar to the classical ones, are obtained. Computed results are found to be in good agreement with theoretical findings on Fourier series expansion presented by Carleson.
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:91090 Serial 7982
Permanent link to this record
 
 
Author Chapman, D.; Gielis, J.
Title Gielis transformations for the audiovisual geometry database Type A1 Journal article
Year 2021 Publication Symmetry : culture and science Abbreviated Journal
Volume 32 Issue 2 Pages 177-180
Keywords (up) 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 Shi, P.; Liu, M.; Ratkowsky, D.A.; Gielis, J.; Su, J.; Yu, X.; Wang, P.; Zhang, L.; Lin, Z.; Schrader, J.
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 33 Issue 4 Pages 1073-1085
Keywords (up) 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 Gielis, J.; Ricci, P.E.; Tavkhelidze, I.
Title The Möbius phenomenon in Generalized Möbius-Listing surfaces and bodies, and Arnold's Cat phenomenon Type A1 Journal article
Year 2021 Publication Advanced Studies : Euro-Tbilisi Mathematical Journal Abbreviated Journal
Volume 14 Issue 4 Pages 17-35
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Möbius bands have been studied extensively, mainly in topology. Generalized Möbius-Listing surfaces and bodies providing a full geometrical generalization, is a quite new field, motivated originally by solutions of boundary value problems. Analogous to cutting of the original Möbius band, for this class of surfaces and bodies, results have been obtained when cutting such bodies or surfaces. In general, cutting leads to interlinked and intertwined different surfaces or bodies, resulting in very complex systems. However, under certain conditions, the result of cutting can be a single surface or body, which reduces complexity considerably. Our research is motivated by this reduction of complexity. In the study of cutting Generalized Möbius-Listing bodies with polygons as cross section, the conditions under which a single body results, displaying the Möbius phenomenon of a one-sided body, have been determined for even and odd polygons. These conditions are based on congruence and rotational symmetry of the resulting cross sections after cutting, and on the knife cutting the origin. The Möbius phenomenon is important, since the process of cutting (or separation of zones in a GML body in general) then results in a single body, not in different, intertwined domains. In all previous works it was assumed that the cross section of the GML bodies is constant, but the main result of this paper is that it is sufficient that only one cross section on the whole GML structure meets the conditions for the Möbius phenomenon to occur. Several examples are given to illustrate this.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000774655100002 Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 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:183081 Serial 8258
Permanent link to this record
 
 
Author Mescia, L.; Chiapperino, M.A.; Bia, P.; Gielis, J.; Caratelli, D.
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 65 Issue 2 Pages 414-423
Keywords (up) 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 Chiapperino, M.A.; Bia, P.; Caratelli, D.; Gielis, J.; Mescia, L.; Dermol-Cerne, J.; Miklavcic, D.
Title Nonlinear dispersive model of electroporation for irregular nucleated cells Type A1 Journal article
Year 2019 Publication Bioelectromagnetics Abbreviated Journal
Volume 40 Issue 5 Pages 331-342
Keywords (up) 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.
Title Phi-bonacci in Ancient Greece Type A1 Journal article
Year 2021 Publication Symmetry : culture and science Abbreviated Journal
Volume 32 Issue 1 Pages 25-40
Keywords (up) 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 Gielis, J.; Brasili, S.
Title The apeirogon and dual numbers Type A1 Journal article
Year 2021 Publication Symmetry : culture and science Abbreviated Journal
Volume 32 Issue 2 Pages 157-160
Keywords (up) 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 Caratelli, D.; Gielis, J.; Natalini, P.; Ricci, P.E.; Tavkhelidze, I.
Title The Robin problem for the Helmholtz equation in a starlike planar domain Type A1 Journal article
Year 2011 Publication Georgian mathematical journal Abbreviated Journal
Volume 18 Issue 3 Pages 465-479
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The interior and exterior Robin problems for the Helmholtz equation in starlike planar domains are addressed by using a suitable Fourier-like technique. Attention is in particular focused on normal-polar domains whose boundaries are defined by the so-called superformula introduced by J. Gielis. A dedicated numerical procedure based on the computer algebra system Mathematica© is developed in order to validate the proposed approach. In this way, highly accurate approximations of the solution, featuring properties similar to the classical ones, are obtained. The computed results are found to be in good agreement with the theoretical findings on Fourier series expansion presented by L. Carleson.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000296166100004 Publication Date 2021-02-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1072-947x 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:91086 Serial 8658
Permanent link to this record
 
 
Author Lian, M.; Shi, P.; Zhang, L.; Yao, W.; Gielis, J.; Niklas, K.J.
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 37 Issue Pages 1555-1565
Keywords (up) 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
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Author Huang, L.; Ratkowsky, D.A.; Hui, C.; Gielis, J.; Lian, M.; Shi, P.
Title Inequality measure of leaf area distribution for a drought-tolerant landscape plant Type A1 Journal article
Year 2023 Publication Plants Abbreviated Journal
Volume 12 Issue 17 Pages 3143-11
Keywords (up) A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Measuring the inequality of leaf area distribution per plant (ILAD) can provide a useful tool for quantifying the influences of intra- and interspecific competition, foraging behavior of herbivores, and environmental stress on plants’ above-ground architectural structures and survival strategies. Despite its importance, there has been limited research on this issue. This paper aims to fill this gap by comparing four inequality indices to measure ILAD, using indices for quantifying household income that are commonly used in economics, including the Gini index (which is based on the Lorenz curve), the coefficient of variation, the Theil index, and the mean log deviation index. We measured the area of all leaves for 240 individual plants of the species Shibataea chinensis Nakai, a drought-tolerant landscape plant found in southern China. A three-parameter performance equation was fitted to observations of the cumulative proportion of leaf area vs. the cumulative proportion of leaves per plant to calculate the Gini index for each individual specimen of S. chinensis. The performance equation was demonstrated to be valid in describing the rotated and right shifted Lorenz curve, given that >96% of root-mean-square error values were smaller than 0.004 for 240 individual plants. By examining the correlation between any of the six possible pairs of indices among the Gini index, the coefficient of variation, the Theil index, and the mean log deviation index, the data show that these indices are closely related and can be used interchangeably to quantify ILAD.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001065193100001 Publication Date 2023-08-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2223-7747 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:199564 Serial 8886
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Author Gielis, J.
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 34 Issue 2 Pages 155-168
Keywords (up) 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
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Author Zhang, L.; Quinn, B.K.; Hui, C.; Lian, M.; Gielis, J.; Gao, J.; Shi, P.
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 35 Issue 1 Pages 31-39
Keywords (up) 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 3 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 3; 2024 IF: 0.774
Call Number UA @ admin @ c:irua:201972 Serial 9061
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Author Caratelli, D.; Gielis, J.; Ricci, P.E.; Tavkhelidze, I.
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 216 Issue 4 Pages 509-518
Keywords (up) 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
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Author Gielis, J.; Tavkhelidze, I.; Ricci, P.E.
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 193 Issue 3 Pages 449-460
Keywords (up) 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
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Author Gielis, J.
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 47 Issue 188 Pages 23-33
Keywords (up) 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
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Author Vermander, C.; De Wael, J.; Gielis, J.
Title De kleine boerderij : twee bijzondere tuinkamers Type A2 Journal article
Year 2019 Publication Groencontact Abbreviated Journal
Volume 45 Issue 5 Pages 14-19
Keywords (up) 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
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Author Tavkhelidze, I.; Gielis, J.
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 33 Issue Pages
Keywords (up) 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
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Author Gielis, J.; Grigolia, R.
Title Lamé curves and Rvachev's R-functions Type A3 Journal article
Year 2022 Publication Sn – 1512-0066 Abbreviated Journal
Volume 37 Issue Pages 1-4
Keywords (up) 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.
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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
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Author Tavkhelidze, I.; Gielis, J.; Pinelas, S.
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 34 Issue Pages 81-84
Keywords (up) 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 Düking, R.; Gielis, J.; Liese, W.
Title Carbon flux and carbon stock in a bamboo stand and their relevance for mitigating climate change Type A3 Journal article
Year 2011 Publication Bamboo Science & Culture Abbreviated Journal
Volume 24 Issue 1 Pages 1-6
Keywords (up) A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract In this report we describe the basics of biological carbon fixation in bamboo forests. Confusing carbon stock with carbon flux has led to false expectations on the significance of bamboo forests as carbon sinks. Furthermore, misunderstandings about the growth of bamboo culms can lead to highly exaggerated expectations on the productivity of bamboo.
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 1535-7635 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:91091 Serial 7578
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