scholarly journals An Intrinsic Geometric Constraint on Morphological Stomatal Traits

2021 ◽  
Vol 12 ◽  
Author(s):  
Lirong Zhang ◽  
Shiping Wang ◽  
Xiaoxia Yang ◽  
Xiaoyong Cui ◽  
Haishan Niu

A strong negative non-linear relationship exists between stomatal density (SD) and size (SS) or length (SL), which is of high importance in gas exchange and plant evolution. However, the cause of this relationship has not been clarified. In geometry, SD has an intrinsic relationship with SS−1 or SL−2, which is defined as a geometric constraint here. We compiled global data to clarify the influence of this geometric constraint on the SD-SS relationship. The log-log scaling slope of the relationship between SD and SS and between SD and SL was not significantly different from −1 and −2, respectively. Although the non-geometric effect drove the SD-SS curve away from the power function with −1, a larger influence of the geometric constraint on SD was found. Therefore, the higher geometric constraint possibly causes the SD-SS relationship to be inevitably non-linear and negative. Compared to pteridophyta and gymnosperms, the geometric constraint was lower for angiosperm species, possibly due to most of them having smaller stomata. The relaxation of the geometric constraint seems to extend the upper range of SD in angiosperm species and hence enable them to exploit a wide range of environments.

1985 ◽  
Vol 24 (02) ◽  
pp. 91-100 ◽  
Author(s):  
W. van Pelt ◽  
Ph. H. Quanjer ◽  
M. E. Wise ◽  
E. van der Burg ◽  
R. van der Lende

SummaryAs part of a population study on chronic lung disease in the Netherlands, an investigation is made of the relationship of both age and sex with indices describing the maximum expiratory flow-volume (MEFV) curve. To determine the relationship, non-linear canonical correlation was used as realized in the computer program CANALS, a combination of ordinary canonical correlation analysis (CCA) and non-linear transformations of the variables. This method enhances the generality of the relationship to be found and has the advantage of showing the relative importance of categories or ranges within a variable with respect to that relationship. The above is exemplified by describing the relationship of age and sex with variables concerning respiratory symptoms and smoking habits. The analysis of age and sex with MEFV curve indices shows that non-linear canonical correlation analysis is an efficient tool in analysing size and shape of the MEFV curve and can be used to derive parameters concerning the whole curve.


2008 ◽  
pp. 61-76
Author(s):  
A. Porshakov ◽  
A. Ponomarenko

The role of monetary factor in generating inflationary processes in Russia has stimulated various debates in social and scientific circles for a relatively long time. The authors show that identification of the specificity of relationship between money and inflation requires a complex approach based on statistical modeling and involving a wide range of indicators relevant for the price changes in the economy. As a result a model of inflation for Russia implying the decomposition of inflation dynamics into demand-side and supply-side factors is suggested. The main conclusion drawn is that during the recent years the volume of inflationary pressures in the Russian economy has been determined by the deviation of money supply from money demand, rather than by money supply alone. At the same time, monetary factor has a long-run spread over time impact on inflation.


2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
H. Babaei-Aghbolagh ◽  
Komeil Babaei Velni ◽  
Davood Mahdavian Yekta ◽  
H. Mohammadzadeh

Abstract We investigate the $$ T\overline{T} $$ T T ¯ -like flows for non-linear electrodynamic theories in D(=2n)-dimensional spacetime. Our analysis is restricted to the deformation problem of the classical free action by employing the proposed $$ T\overline{T} $$ T T ¯ operator from a simple integration technique. We show that this flow equation is compatible with $$ T\overline{T} $$ T T ¯ deformation of a scalar field theory in D = 2 and of a non-linear Born-Infeld type theory in D = 4 dimensions. However, our computation discloses that this kind of $$ T\overline{T} $$ T T ¯ flow in higher dimensions is essentially different from deformation that has been derived from the AdS/CFT interpretations. Indeed, the gravity that may be exist as a holographic dual theory of this kind of effective Born-Infeld action is not necessarily an AdS space. As an illustrative investigation in D = 4, we shall also show that our construction for the $$ T\overline{T} $$ T T ¯ operator preserves the original SL(2, ℝ) symmetry of a non-supersymmetric Born-Infeld theory, as well as $$ \mathcal{N} $$ N = 2 supersymmetric model. It is shown that the corresponding SL(2, ℝ) invariant action fixes the relationship between the $$ T\overline{T} $$ T T ¯ operator and quadratic form of the energy-momentum tensor in D = 4.


2021 ◽  
Vol 43 (1) ◽  
pp. 1-79
Author(s):  
Colin S. Gordon

Effect systems are lightweight extensions to type systems that can verify a wide range of important properties with modest developer burden. But our general understanding of effect systems is limited primarily to systems where the order of effects is irrelevant. Understanding such systems in terms of a semilattice of effects grounds understanding of the essential issues and provides guidance when designing new effect systems. By contrast, sequential effect systems—where the order of effects is important—lack an established algebraic structure on effects. We present an abstract polymorphic effect system parameterized by an effect quantale—an algebraic structure with well-defined properties that can model the effects of a range of existing sequential effect systems. We define effect quantales, derive useful properties, and show how they cleanly model a variety of known sequential effect systems. We show that for most effect quantales, there is an induced notion of iterating a sequential effect; that for systems we consider the derived iteration agrees with the manually designed iteration operators in prior work; and that this induced notion of iteration is as precise as possible when defined. We also position effect quantales with respect to work on categorical semantics for sequential effect systems, clarifying the distinctions between these systems and our own in the course of giving a thorough survey of these frameworks. Our derived iteration construct should generalize to these semantic structures, addressing limitations of that work. Finally, we consider the relationship between sequential effects and Kleene Algebras, where the latter may be used as instances of the former.


2021 ◽  
pp. 1-8
Author(s):  
Paul Theo Zebhauser ◽  
Achim Berthele ◽  
Marie-Sophie Franz ◽  
Oliver Goldhardt ◽  
Janine Diehl-Schmid ◽  
...  

Background: Tau proteins are established biomarkers of neuroaxonal damage in a wide range of neurodegenerative conditions. Although measurement of total-Tau in the cerebrospinal fluid is widely used in research and clinical settings, the relationship between age and total-Tau in the cerebrospinal fluid is yet to be fully understood. While past studies reported a correlation between age and total-Tau in the cerebrospinal fluid of healthy adults, in clinical practice the same cut-off value is used independently of patient’s age. Objective: To further explore the relationship between age and total-Tau and to disentangle neurodegenerative from drainage-dependent effects. Methods: We analyzed cerebrospinal fluid samples of 76 carefully selected cognitively healthy adults and included amyloid-β 1–40 as a potential marker of drainage from the brain’s interstitial system. Results: We found a significant correlation of total-Tau and age, which was no longer present when correcting total-Tau for amyloid-β 1–40 concentrations. These findings were replicated under varied inclusion criteria. Conclusion: Results call into question the association of age and total-Tau in the cerebrospinal fluid. Furthermore, they suggest diagnostic utility of amyloid-β 1–40 as a possible proxy for drainage-mechanisms into the cerebrospinal fluid when interpreting biomarker concentrations for neurodegenerative diseases.


2020 ◽  
Vol 6 (1) ◽  
pp. 50-56
Author(s):  
Francesco Baino ◽  
Elisa Fiume

AbstractPorosity is known to play a pivotal role in dictating the functional properties of biomedical scaffolds, with special reference to mechanical performance. While compressive strength is relatively easy to be experimentally assessed even for brittle ceramic and glass foams, elastic properties are much more difficult to be reliably estimated. Therefore, describing and, hence, predicting the relationship between porosity and elastic properties based only on the constitutive parameters of the solid material is still a challenge. In this work, we quantitatively compare the predictive capability of a set of different models in describing, over a wide range of porosity, the elastic modulus (7 models), shear modulus (3 models) and Poisson’s ratio (7 models) of bioactive silicate glass-derived scaffolds produced by foam replication. For these types of biomedical materials, the porosity dependence of elastic and shear moduli follows a second-order power-law approximation, whereas the relationship between porosity and Poisson’s ratio is well fitted by a linear equation.


2015 ◽  
Vol 19 (5) ◽  
pp. 488-530
Author(s):  
Cynthia Fowler

This article examines the Religious Art of Today exhibition, originally held in 1944 at Boston’s Institute of Modern Art and then reformulated for the Dayton Art Institute in Ohio. The exhibition was eclectic in that it included a wide range of artists and a diversity of faiths, and engaged the debate held among museum professionals about the relationship between religion and modern art. The article focuses closely on Catholic, Jewish, and Navajo art included in the exhibition. The IMA’s commitment to the figurative tradition afforded artists the opportunity to explore their identities—as Jews, as Catholics, as Navajos—using recognizable religious subjects. That the works in the exhibition were selected as representative of modern art resulted in a convergence of discourses related to modern art with those of religious/cultural identity.


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3888
Author(s):  
Boon-Peng Puah ◽  
Juriyati Jalil ◽  
Ali Attiq ◽  
Yusof Kamisah

Lycopene is a well-known compound found commonly in tomatoes which brings wide range of health benefits against cardiovascular diseases and cancers. From an anti-cancer perspective, lycopene is often associated with reduced risk of prostate cancer and people often look for it as a dietary supplement which may help to prevent cancer. Previous scientific evidence exhibited that the anti-cancer activity of lycopene relies on its ability to suppress oncogene expressions and induce proapoptotic pathways. To further explore the real potential of lycopene in cancer prevention, this review discusses the new insights and perspectives on the anti-cancer activities of lycopene which could help to drive new direction for research. The relationship between inflammation and cancer is being highlighted, whereby lycopene suppresses cancer via resolution of inflammation are also discussed herein. The immune system was found to be a part of the anti-cancer system of lycopene as it modulates immune cells to suppress tumor growth and progression. Lycopene, which is under the family of carotenoids, was found to play special role in suppressing lung cancer.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ryo Matsuzaki ◽  
Shigekatsu Suzuki ◽  
Haruyo Yamaguchi ◽  
Masanobu Kawachi ◽  
Yu Kanesaki ◽  
...  

Abstract Background Pyrenoids are protein microcompartments composed mainly of Rubisco that are localized in the chloroplasts of many photosynthetic organisms. Pyrenoids contribute to the CO2-concentrating mechanism. This organelle has been lost many times during algal/plant evolution, including with the origin of land plants. The molecular basis of the evolutionary loss of pyrenoids is a major topic in evolutionary biology. Recently, it was hypothesized that pyrenoid formation is controlled by the hydrophobicity of the two helices on the surface of the Rubisco small subunit (RBCS), but the relationship between hydrophobicity and pyrenoid loss during the evolution of closely related algal/plant lineages has not been examined. Here, we focused on, the Reticulata group of the unicellular green algal genus Chloromonas, within which pyrenoids are present in some species, although they are absent in the closely related species. Results Based on de novo transcriptome analysis and Sanger sequencing of cloned reverse transcription-polymerase chain reaction products, rbcS sequences were determined from 11 strains of two pyrenoid-lacking and three pyrenoid-containing species of the Reticulata group. We found that the hydrophobicity of the RBCS helices was roughly correlated with the presence or absence of pyrenoids within the Reticulata group and that a decrease in the hydrophobicity of the RBCS helices may have primarily caused pyrenoid loss during the evolution of this group. Conclusions Although we suggest that the observed correlation may only exist for the Reticulata group, this is still an interesting study that provides novel insight into a potential mechanism determining initial evolutionary steps of gain and loss of the pyrenoid.


2020 ◽  
Vol 12 (9) ◽  
pp. 3668 ◽  
Author(s):  
Rakan Alyamani ◽  
Suzanna Long ◽  
Mohammad Nurunnabi

With the increase in awareness about the wide range of issues and adverse effects associated with the use of conventional energy sources came an increase in project management research related to sustainability and sustainable development. Part of that research is devoted to the development of sustainable project typologies that classify projects based on a variety of external factors that can significantly impact these projects. This research focuses on developing a sustainable project typology that classifies sustainable projects based on the external institutional influences. The typology explores the influence of the coercive, normative, and mimetic institutional isomorphisms on the expected level of change, level of uncertainty, project team skills and experience levels, and the level of technology information exchange in sustainable projects. Two case studies are presented to demonstrate the use of the typology to classify sustainable projects based on the external institutional influences.


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