Records |
Author |
Tian, F.; Wang, Y.; Sandhu, H.S.; Gielis, J.; Shi, P. |
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 |
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 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000529367600005 |
Publication Date |
2018-07-28 |
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Series Title |
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Abbreviated Series Title |
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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 |
Permanent link to this record |
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|
|
Author |
Shi, P.; Ratkowsky, D.A.; Gielis, J. |
Title |
The generalized Gielis geometric equation and its application |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Symmetry-Basel |
Abbreviated Journal |
Symmetry-Basel |
Volume |
12 |
Issue |
4 |
Pages |
645-10 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Many natural shapes exhibit surprising symmetry and can be described by the Gielis equation, which has several classical geometric equations (for example, the circle, ellipse and superellipse) as special cases. However, the original Gielis equation cannot reflect some diverse shapes due to limitations of its power-law hypothesis. In the present study, we propose a generalized version by introducing a link function. Thus, the original Gielis equation can be deemed to be a special case of the generalized Gielis equation (GGE) with a power-law link function. The link function can be based on the morphological features of different objects so that the GGE is more flexible in fitting the data of the shape than its original version. The GGE is shown to be valid in depicting the shapes of some starfish and plant leaves. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000540222200156 |
Publication Date |
2020-04-21 |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2073-8994 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.7 |
Times cited |
4 |
Open Access |
|
Notes |
; This research was funded by the Jiangsu Government Scholarship for Overseas Studies (grant number: JS-2018-038). ; |
Approved |
Most recent IF: 2.7; 2020 IF: 1.457 |
Call Number |
UA @ admin @ c:irua:168141 |
Serial |
6526 |
Permanent link to this record |
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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 |
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 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2020-02-23 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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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 |
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|
|
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 |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
|
Publication Date |
2020-03-04 |
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Series Title |
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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 |
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|
|
Author |
Shi, P.; Gielis, J.; Quinn, B.K.; Niklas, K.J.; Ratkowsky, D.A.; Schrader, J.; Ruan, H.; Wang, L.; Niinemets, Ü.; Niinennets, U. |
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 |
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 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000829772300001 |
Publication Date |
2022-07-26 |
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Series Title |
|
Abbreviated Series Title |
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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 |
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|
|
Author |
Shi, P.; Gielis, J.; Niklas, K.J. |
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 |
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 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000803394100001 |
Publication Date |
2022-06-01 |
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Series Title |
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Abbreviated Series Title |
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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 |
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|
|
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 |
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 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000695118600001 |
Publication Date |
2021-09-12 |
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Series Title |
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Abbreviated Series Title |
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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 |
Permanent link to this record |
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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 |
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 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000814279700028 |
Publication Date |
2022-05-23 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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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 |
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Author |
Li, Y.; Quinn, B.K.; Gielis, J.; Li, Y.; Shi, P. |
Title |
Evidence that supertriangles exist in nature from the vertical projections of Koelreuteria paniculata fruit |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Symmetry |
Abbreviated Journal |
Symmetry-Basel |
Volume |
14 |
Issue |
1 |
Pages |
23 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Many natural radial symmetrical shapes (e.g., sea stars) follow the Gielis equation (GE) or its twin equation (TGE). A supertriangle (three triangles arranged around a central polygon) represents such a shape, but no study has tested whether natural shapes can be represented as/are supertriangles or whether the GE or TGE can describe their shape. We collected 100 pieces of Koelreuteria paniculata fruit, which have a supertriangular shape, extracted the boundary coordinates for their vertical projections, and then fitted them with the GE and TGE. The adjusted root mean square errors (RMSEadj) of the two equations were always less than 0.08, and >70% were less than 0.05. For 57/100 fruit projections, the GE had a lower RMSEadj than the TGE, although overall differences in the goodness of fit were non-significant. However, the TGE produces more symmetrical shapes than the GE as the two parameters controlling the extent of symmetry in it are approximately equal. This work demonstrates that natural supertriangles exist, validates the use of the GE and TGE to model their shapes, and suggests that different complex radially symmetrical shapes can be generated by the same equation, implying that different types of biological symmetry may result from the same biophysical mechanisms. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000746030100001 |
Publication Date |
2021-12-27 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2073-8994 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.7 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 2.7 |
Call Number |
UA @ admin @ c:irua:186453 |
Serial |
7158 |
Permanent link to this record |
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Author |
Nicolau, F.; Gielis, J.; Simeone, A.L.; Simoes Lopes, D. |
Title |
Exploring and selecting supershapes in virtual reality with line, quad, and cube shaped widgets |
Type |
P1 Proceeding |
Year |
2022 |
Publication |
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Abbreviated Journal |
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Volume |
|
Issue |
|
Pages |
21-28 |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Supershapes are used in Parametric Design to model, literally, thou-sands of natural and man-made shapes with a single 6 parameter formula. However, users are left to probe such a rich yet dense collection of supershapes using a set of independent 1-D sliders. Some of the formula’s parameters are non-linear in nature, making them particularly difficult to grasp with conventional 1-D sliders alone. VR appears as a promising setting for Parametric Design with supershapes since it empowers users with more natural visual inspection and shape browsing techniques, with multiple solutions being displayed at once and the possibility to design more interesting forms of slider interaction. In this work, we propose VR shape widgets that allow users to probe and select supershapes from a multitude of solutions. Our designs take leverage on thumbnails, mini-maps, haptic feedback and spatial interaction, while supporting 1-D, 2-D and 3-D supershape parameter spaces. We conducted a user study (N = 18) and found that VR shape widgets are effective, more efficient, and natural than conventional VR 1-D sliders while also usable for users without prior knowledge on supershapes. We also found that the proposed VR widgets provide a quick overview of the main supershapes, and users can easily reach the desired solution without having to perform fine-grain handle manipulations. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000828657500003 |
Publication Date |
2022-04-20 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
978-1-6654-9617-9 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:188471 |
Serial |
7161 |
Permanent link to this record |
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Author |
De Tommasi, E.; Rogato, A.; Caratelli, D.; Mescia, L.; Gielis, J. |
Title |
Following the photons route : mathematical models describing the interaction of diatoms with light |
Type |
H1 Book chapter |
Year |
2022 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
|
Pages |
1-53 |
Keywords |
H1 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The interaction of diatoms with sunlight is fundamental in order to deeply understand their role in terrestrial ecology and biogeochemistry, essentially due to their massive contribution to global primary production through photosynthesis and its e↵ect on carbon, oxygen and silicon cycles. Following the journey of light through natural waters, its propagation through the intricate frustule micro- and nano-structure and, finally, its fate inside the photosynthetic machinery of the living cell requires several mathematical and computational models in order to accurately describe all the involved phenomena taking place at di↵erent space scales and physical regimes. In this chapter, we review the main analytical models describing the underwater optical field, the essential numerical algorithms for the study of photonic properties of the diatom frustule seen as a natural metamaterial, as well as the principal models describing photon harvesting in diatom plastids and methods for complex EM propagation problems and wave propagation in dispersive materials with multiple relaxation times. These mathematical methods will be integrated in a unifying geometric perspective. |
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Place of Publication |
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Wos |
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Publication Date |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
|
ISBN |
978-1-119-74985-1 |
Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:186731 |
Serial |
7165 |
Permanent link to this record |
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Author |
Ricci, P.E.; Gielis, J. |
Title |
From Pythagoras to Fourier and from geometry to nature |
Type |
MA3 Book as author |
Year |
2022 |
Publication |
|
Abbreviated Journal |
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Volume |
|
Issue |
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Pages |
146 p. |
Keywords |
MA3 Book as author; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2022-03-23 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
978-90-832323-0-0; 978-90-832323-1-7 |
Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:186730 |
Serial |
7166 |
Permanent link to this record |
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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 |
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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Open Access |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:189316 |
Serial |
7178 |
Permanent link to this record |
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Author |
Wang, L.; Miao, Q.; Niinemets, Ü.; Gielis, J.; Shi, P. |
Title |
Quantifying the variation in the geometries of the outer rims of corolla tubes of Vinca major L |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Plants |
Abbreviated Journal |
|
Volume |
11 |
Issue |
15 |
Pages |
1987-12 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Many geometries of plant organs can be described by the Gielis equation, a polar coordinate equation extended from the superellipse equation, . Here, r is the polar radius corresponding to the polar angle φ; m is a positive integer that determines the number of angles of the Gielis curve when φ ∈ [0 to 2π); and the rest of the symbols are parameters to be estimated. The pentagonal radial symmetry of calyxes and corolla tubes in top view is a common feature in the flowers of many eudicots. However, prior studies have not tested whether the Gielis equation can depict the shapes of corolla tubes. We sampled randomly 366 flowers of Vinca major L., among which 360 had five petals and pentagonal corolla tubes, and six had four petals and quadrangular corolla tubes. We extracted the planar coordinates of the outer rims of corolla tubes (in top view) (ORCTs), and then fitted the data with two simplified versions of the Gielis equation with k = 1 and m = 5: (Model 1), and (Model 2). The adjusted root mean square error (RMSEadj) was used to evaluate the goodness of fit of each model. In addition, to test whether ORCTs are radially symmetrical, we correlated the estimates of n2 and n3 in Model 1 on a log-log scale. The results validated the two simplified Gielis equations. The RMSEadj values for all corolla tubes were smaller than 0.05 for both models. The numerical values of n2 and n3 were demonstrated to be statistically equal based on the regression analysis, which suggested that the ORCTs of V. major are radially symmetrical. It suggests that Model 1 can be replaced by the simpler Model 2 for fitting the ORCT in this species. This work indicates that the pentagonal or quadrangular corolla tubes (in top view) can both be modeled by the Gielis equation and demonstrates that the pentagonal or quadrangular corolla tubes of plants tend to form radial symmetrical geometries during their development and growth. |
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Wos |
000839115100001 |
Publication Date |
2022-08-01 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2223-7747 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:189315 |
Serial |
7200 |
Permanent link to this record |
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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 |
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Volume |
|
Issue |
|
Pages |
|
Keywords |
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 |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:189317 |
Serial |
7224 |
Permanent link to this record |
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Author |
Shi, P.; Wang, L.; Quinn, B.K.K.; Gielis, J. |
Title |
A new program to estimate the parameters of Preston's equation, a general formula for describing the egg shape of birds |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Symmetry |
Abbreviated Journal |
Symmetry-Basel |
Volume |
15 |
Issue |
1 |
Pages |
231-10 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Preston's equation is a general model describing the egg shape of birds. The parameters of Preston's equation are usually estimated after re-expressing it as the Todd-Smart equation and scaling the egg's actual length to two. This method assumes that the straight line through the two points on an egg's profile separated by the maximum distance (i.e., the longest axis of an egg's profile) is the mid-line. It hypothesizes that the photographed egg's profile is perfectly bilaterally symmetrical, which seldom holds true because of photographic errors and placement errors. The existing parameter estimation method for Preston's equation considers an angle of deviation for the longest axis of an egg's profile from the mid-line, which decreases prediction errors to a certain degree. Nevertheless, this method cannot provide an accurate estimate of the coordinates of the egg's center, and it leads to sub-optimal parameter estimation. Thus, it is better to account for the possible asymmetry between the two sides of an egg's profile along its mid-line when fitting egg-shape data. In this paper, we propose a method based on the optimization algorithm (optimPE) to fit egg-shape data and better estimate the parameters of Preston's equation by automatically searching for the optimal mid-line of an egg's profile and testing its validity using profiles of 59 bird eggs spanning a wide range of existing egg shapes. We further compared this method with the existing one based on multiple linear regression (lmPE). This study demonstrated the ability of the optimPE method to estimate numerical values of the parameters of Preston's equation and provide the theoretical egg length (i.e., the distance between two ends of the mid-line of an egg's profile) and the egg's maximum breadth. This provides a valuable approach for comparing egg shapes among conspecifics or across different species, or even different classes (e.g., birds and reptiles), in future investigations. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Language |
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Wos |
000927531000001 |
Publication Date |
2023-01-13 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2073-8994 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.7 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 2.7; 2023 IF: 1.457 |
Call Number |
UA @ admin @ c:irua:195347 |
Serial |
7279 |
Permanent link to this record |
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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 |
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. |
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Wos |
000887783400001 |
Publication Date |
2022-11-14 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2223-7747 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:191859 |
Serial |
7289 |
Permanent link to this record |
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Author |
Wang, L.; Ratkowsky, D.A.; Gielis, J.; Ricci, P.E.; Shi, P. |
Title |
Effects of the numerical values of the parameters in the Gielis equation on its geometries |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Symmetry |
Abbreviated Journal |
Symmetry-Basel |
Volume |
14 |
Issue |
12 |
Pages |
2475-12 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The Lamé curve is an extension of an ellipse, the latter being a special case. Dr. Johan Gielis further extended the Lamé curve in the polar coordinate system by introducing additional parameters (n1, n2, n3; m): rφ=1Acosm4φn2+1Bsinm4φn3−1/n1, which can be applied to model natural geometries. Here, r is the polar radius corresponding to the polar angle φ; A, B, n1, n2 and n3 are parameters to be estimated; m is the positive real number that determines the number of angles of the Gielis curve. Most prior studies on the Gielis equation focused mainly on its applications. However, the Gielis equation can also generate a large number of shapes that are rotationally symmetric and axisymmetric when A = B and n2 = n3, interrelated with the parameter m, with the parameters n1 and n2 determining the shapes of the curves. In this paper, we prove the relationship between m and the rotational symmetry and axial symmetry of the Gielis curve from a theoretical point of view with the condition A = B, n2 = n3. We also set n1 and n2 to take negative real numbers rather than only taking positive real numbers, then classify the curves based on extremal properties of r(φ) at φ = 0, π/m when n1 and n2 are in different intervals, and analyze how n1, n2 precisely affect the shapes of Gielis curves. |
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Corporate Author |
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Place of Publication |
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Wos |
000904525700001 |
Publication Date |
2022-11-23 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2073-8994 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
2.7 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 2.7 |
Call Number |
UA @ admin @ c:irua:191860 |
Serial |
7301 |
Permanent link to this record |
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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 |
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Volume |
9 |
Issue |
11 |
Pages |
714 |
Keywords |
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. |
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Corporate Author |
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Place of Publication |
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Wos |
000451310300054 |
Publication Date |
2018-11-21 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1999-4907 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:156324 |
Serial |
7389 |
Permanent link to this record |
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Author |
Gielis, J.; Tavkelidze, I.; Ricci, P.E. |
Title |
About “bulky” links, generated by generalized Möbius-Listing bodies |
Type |
H3 Book chapter |
Year |
2011 |
Publication |
|
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
115-128
T2 - Proceedings of the International Conf |
Keywords |
H3 Book chapter; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
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Place of Publication |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
978-9941-0-3727-6 |
Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:97753 |
Serial |
7403 |
Permanent link to this record |
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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 |
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. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
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Publication Date |
2013-08-03 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1072-3374; 1573-8795 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:110953 |
Serial |
7404 |
Permanent link to this record |
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Author |
Tavkhelidze, I.; Cassisa, C.; Gielis, J.; Ricci, P.E. |
Title |
About “bulky” links, generated by generalized Möbius Listing's bodies GML3n |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Matematica e applicazioni : atti della Accademia nazionale dei Lincei |
Abbreviated Journal |
|
Volume |
24 |
Issue |
1 |
Pages |
11-38 |
Keywords |
A1 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'', which appear after cutting a Generalized Möbius Listing's GMLn3 body (whose radial cross section is a plane 3-symmetric figure with three vertices) along different Generalized Möbius Listing's surfaces GMLn2 situated in it. This article is aimed to investigate the number and geometric structure of the independent objects appearing after such a cutting process of GMLn3 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. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000316567700002 |
Publication Date |
2013-03-13 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1120-6357 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:107174 |
Serial |
7405 |
Permanent link to this record |
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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 |
A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:174475 |
Serial |
7406 |
Permanent link to this record |
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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 |
H1 Book chapter |
Year |
2020 |
Publication |
|
Abbreviated Journal |
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Volume |
|
Issue |
|
Pages |
347-359
T2 - Differential and difference equations |
Keywords |
H1 Book chapter; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2020-10-21 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
|
ISBN |
978-3-030-56322-6 |
Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:174479 |
Serial |
7407 |
Permanent link to this record |
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|
Author |
Bia, P.; Caratelli, D.; Mescia, L.; Gielis, J. |
Title |
Analysis and synthesis of supershaped dielectric lens antennas |
Type |
A1 Journal article |
Year |
2015 |
Publication |
IET microwaves, antennas and propagation |
Abbreviated Journal |
|
Volume |
9 |
Issue |
14 |
Pages |
1497-1504 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Mass communications; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
A novel class of supershaped dielectric lens antennas, whose geometry is described by the three-dimensional (3D) Gielis formula, is introduced and analysed. To this end, a hybrid modelling approach based on geometrical and physical optics is adopted in order to efficiently analyse the multiple wave reflections occurring within the lens and to evaluate the relevant impact on the radiation properties of the antenna under analysis. The developed modelling procedure has been validated by comparison with numerical results already reported in the literature and, afterwards, applied to the electromagnetic characterisation of Gielis dielectric lens antennas with shaped radiation pattern. Furthermore, a dedicated optimisation algorithm based on quantum particle swarm optimisation has been developed for the synthesis of 3D supershaped lens antennas with single feed, as well as with beamforming capabilities. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000364491200002 |
Publication Date |
2015-08-14 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1751-8725 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
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Open Access |
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Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:128659 |
Serial |
7441 |
Permanent link to this record |
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|
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Author |
de Jong van Coevorden, C.M.; Gielis, J.; Caratelli, D. |
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 |
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. |
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Wos |
000435022800008 |
Publication Date |
2018-02-20 |
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ISSN |
1742-6588; 1742-6596 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Open Access |
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Call Number |
UA @ admin @ c:irua:150947 |
Serial |
7475 |
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Author |
Gielis, J.; Caratelli, D.; Fougerolle, Y.; Ricci, P.E.; Gerats, T. |
Title |
A biogeometrical model for corolla fusion in Asclepiad flowers |
Type |
H1 Book chapter |
Year |
2017 |
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Abbreviated Journal |
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Volume |
2 |
Issue |
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Pages |
83-105
T2 - Modeling in mathematics : proceedings |
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H1 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The molecular genetics of flower development have been studied extensively for more than two decades. Fusion of organs and the tendency to oligomery, important characteristics of flower evolution, so far have remained fairly elusive. We present a geometric model for shape and fusion in the corolla of Asclepiads. Examples demonstrate how fusion of petals creates stable centers, a prerequisite for the formation of complex pollination structures via congenital and postgenital fusion events, with the formation of de novo organs, specific to Asclepiads. The development of the corolla reduces to simple inequalities from the MATHS-BOX. The formation of stable centers and of bell and tubular shapes in flowers are immediate and logical consequences of the shape. Our model shows that any study on flowers, especially in evo-devo perspective should be performed within the wider framework of polymery and oligomery and of fusion and synorganization. |
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000442076400007 |
Publication Date |
2017-04-20 |
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ISBN |
978-94-6239-260-1; 978-94-6239-261-8; 2543-0300; 978-94-6239-260-1 |
Additional Links |
UA library record; WoS full record; WoS citing articles |
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no |
Call Number |
UA @ admin @ c:irua:144551 |
Serial |
7561 |
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Author |
Gielis, J.; Caratelli, D.; Tavkelidze, I.; Fougerolle, Y.; Ricci, P.E.; Gerats, T. |
Title |
Bulky knots and links generated by cutting generalized Mobius-Listing bodies and applications in the natural sciences |
Type |
H2 Book chapter |
Year |
2013 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
167-183
T2 - Math Art Summit : Koninklijke Vlaamse |
Keywords |
H2 Book chapter; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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ISBN |
978-90-6569-119-4 |
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UA library record |
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no |
Call Number |
UA @ admin @ c:irua:110955 |
Serial |
7569 |
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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 |
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. |
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000611074700001 |
Publication Date |
2020-12-31 |
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ISSN |
1999-4907 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.951 |
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Open Access |
OpenAccess |
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Approved |
Most recent IF: 1.951 |
Call Number |
UA @ admin @ c:irua:174473 |
Serial |
7572 |
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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 |
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A3 Journal article |
Year |
2011 |
Publication |
Bamboo Science & Culture |
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Volume |
24 |
Issue |
1 |
Pages |
1-6 |
Keywords |
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. |
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ISSN |
1535-7635 |
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UA library record |
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Call Number |
UA @ admin @ c:irua:91091 |
Serial |
7578 |
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