Radial-axial transport coordination enhances sugar translocation in the phloem vasculature of plants

Understanding the controls of mass transport of photosynthates in the phloem of plants is necessary for describing plant carbon allocation, productivity, and responses to water and thermal stress. While several hypotheses about optimization of phloem structure and function, and limitations of phloem transport under drought have been tested both with models and anatomical data, the true impact of radial water exchange of phloem conduits with their surroundings on mass transport of photosynthates has not been addressed. Here the physics of the Munch mechanism of sugar transport is re-evaluated to include local variations in viscosity resulting from the radial water exchange in two dimensions (axial and radial). Model results show that radial water exchange pushes sucrose away from conduit walls thereby reducing wall frictional stress due to a decrease in sap viscosity and increasing sugar concentration in the central region of the conduit. This leads to increased sugar front speed and axial mass transport for a wide range of phloem conduit lengths and allows sugar transport to operate more efficiently than predicted by previous models. A faster front speed leads to higher phloem resiliency under drought because more sugar can be transported with a smaller pressure gradient.

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Chaperonin as the normal controls and pathological anti-stress response in the human reproductive system

HEALTH OF WOMAN ◽

10.15574/hw.2016.111.126 ◽

2016 ◽

pp. 126-129

Author(s):

M. Makarenko ◽

◽

D. Hovsyeyev ◽

L. Sydoryk ◽

◽

...

Keyword(s):

Reproductive System ◽

Stress Proteins ◽

Physiological Stress ◽

Protein Complexes ◽

Reproductive Function ◽

Intercellular Signaling ◽

Toll Like Receptors ◽

Wide Range ◽

Protein Functions ◽

And Function

Different kinds of physiological stress cause mass changes in the cells, including the changes in the structure and function of the protein complexes and in separate molecules. The protein functions is determined by its folding (the spatial conclusion), which depends on the functioning of proteins of thermal shock- molecular chaperons (HSPs) or depends on the stress proteins, that are high-conservative; specialized proteins that are responsible for the correct proteinaceous folding. The family of the molecular chaperones/ chaperonins/ Hsp60 has a special place due to the its unique properties of activating the signaling cascades through the system of Toll-like receptors; it also stimulates the cells to produce anti- inflammatory cytokines, defensins, molecules of cell adhesion and the molecules of MHC; it functions as the intercellular signaling molecule. The pathological role of Hsp60 is established in a wide range of illnesses, from diabetes to atherosclerosis, where Hsp60 takes part in the regulation of both apoptosis and the autoimmune processes. The presence of the HSPs was found in different tissues that are related to the reproductive system. Key words: molecular chaperons (HSPs), Toll-like receptors, reproductive function, natural auto antibody.

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Possession and Repetition

Postscripts The Journal of Sacred Texts and Contemporary Worlds ◽

10.1558/post.v6i1-3.243 ◽

2012 ◽

Vol 6 (1-3) ◽

pp. 243-259 ◽

Cited By ~ 2

Author(s):

Yohan Yoo

Keyword(s):

First Century ◽

Daily Lives ◽

Modern Times ◽

Sacred Texts ◽

New Methods ◽

Wide Range ◽

Lay Buddhists ◽

Iconic Status ◽

And Function ◽

To Receive

This article demonstrates the need for the iconic status and function of Buddhist scripture to receive more attention by illuminating how lay Korean Buddhists try to appropriate the power of sutras. The oral and aural aspects of scripture, explained by Wilfred Cantwell Smith, provide only a limited understanding of the characteristics of scripture. It should be noted that, before modern times, most lay people, not only in Buddhist cultures but also in Christian and other traditions, neither had the chance to recite scriptures nor to listen to their recitations regularly. Several clear examples demonstrate contemporary Korean Buddhists’ acceptance of the iconic status of sutras and their attempt to appropriate the power and status of those sacred texts. In contemporary Korea, lay Buddhists try to claim the power of scriptures in their daily lives by repeating and possessing them. Twenty-first century lay believers who cannot read or recite in a traditional style have found new methods of repetition, such as internet programs for copying sacred texts and for playing recordings of their recitations. In addition, many Korean Buddhists consider the act of having sutras in one’s possession to be an effective way of accessing the sacred status and power of these texts. Hence, various ways of possessing them have been developed in a wide range of products, from fancy gilded sutras to sneakers embroidered with mantras.

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The Art of Love Poetry

10.1093/oso/9780198752974.001.0001 ◽

2018 ◽

Author(s):

Erik Gray

Keyword(s):

Popular Culture ◽

Cultural History ◽

Literary Tradition ◽

Love Poetry ◽

Erotic Love ◽

Wide Range ◽

History Of ◽

And Function ◽

Meaning And Function ◽

Comprehensive History

Love begets poetry; poetry begets love. These two propositions have seemed evident to thinkers and poets across the Western literary tradition. Plato writes that “anyone that love touches instantly becomes a poet.” And even today, when poetry has largely disappeared from the mainstream of popular culture, it retains its romantic associations. But why should this be so—what are the connections between poetry and erotic love that lead us to associate them so strongly with one another? An examination of different theories of both love and poetry across the centuries reveals that the connection between them is not merely an accident of cultural history—the result of our having grown up hearing, or hearing about, love poetry—but something more intrinsic. Even as definitions of them have changed, the two phenomena have consistently been described in parallel terms. Love is characterized by paradox. Above all, it is both necessarily public, because interpersonal, and intensely private; hence it both requires expression and resists it. In poetry, especially lyric poetry, which features its own characteristic paradoxes and silences, love finds a natural outlet. This study considers both the theories and the love poems themselves, bringing together a wide range of examples from different eras in order to examine the major structures that love and poetry share. It does not aim to be a comprehensive history of Western love poetry, but an investigation into the meaning and function of recurrent tropes, forms, and images employed by poets to express and describe erotic love.

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TOWARDS FUNCTIONAL ARCHITECTURAL DECOMPOSITION OF CONSTRAINED LAYER INFLATABLE SYSTEMS

Proceedings of the Design Society ◽

10.1017/pds.2021.583 ◽

2021 ◽

Vol 1 ◽

pp. 3219-3228

Author(s):

Koray Benli ◽

Jonathan Luntz ◽

Diann Brei ◽

Wonhee Kim ◽

Paul Alexander ◽

...

Keyword(s):

Conceptual Design ◽

Form And Function ◽

New Concepts ◽

Wide Range ◽

Systematic Understanding ◽

And Function

AbstractPneumatically activated systems enable myriad types of highly functional inflatables employing a wide range of architectural approaches affecting their form and function, making systematic conceptual design difficult. A new architectural class of pneumatically activated systems, constrained layer inflatable systems, consists of hierarchically architected flat layers of thin airtight bladders that are internally and/or externally constrained to generate a variety of functionalities. The highly hierarchical architectural structure of constrained layer inflatable systems coincides with the hierarchy of produced functions, providing an opportunity for the development of a functional architectural decomposition, capturing the inherent relationship between architectural and functional hierarchies. The basis of the approach is conveyed through the design of an example constrained layer inflatable system. This approach empowers the systematic understanding of the interrelated architectural and functional breakdown of constrained layer inflatable systems, enabling designers to iteratively analyze, synthesize, and re-synthesize the components of the system improving existing designs and exploring new concepts.

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Adjustment models for multivariate geodetic time series with vector-autoregressive errors

Journal of Applied Geodesy ◽

10.1515/jag-2021-0013 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Boris Kargoll ◽

Alexander Dorndorf ◽

Mohammad Omidalizarandi ◽

Jens-André Paffenholz ◽

Hamza Alkhatib

Keyword(s):

Least Squares Method ◽

Functional Model ◽

Expectation Maximization Algorithm ◽

Two Dimensions ◽

Vector Autoregressive ◽

Wide Range ◽

Engineering Geodesy ◽

Cross Correlations ◽

T Distribution ◽

Multivariate T

Abstract In this contribution, a vector-autoregressive (VAR) process with multivariate t-distributed random deviations is incorporated into the Gauss-Helmert model (GHM), resulting in an innovative adjustment model. This model is versatile since it allows for a wide range of functional models, unknown forms of auto- and cross-correlations, and outlier patterns. Subsequently, a computationally convenient iteratively reweighted least squares method based on an expectation maximization algorithm is derived in order to estimate the parameters of the functional model, the unknown coefficients of the VAR process, the cofactor matrix, and the degree of freedom of the t-distribution. The proposed method is validated in terms of its estimation bias and convergence behavior by means of a Monte Carlo simulation based on a GHM of a circle in two dimensions. The methodology is applied in two different fields of application within engineering geodesy: In the first scenario, the offset and linear drift of a noisy accelerometer are estimated based on a Gauss-Markov model with VAR and multivariate t-distributed errors, as a special case of the proposed GHM. In the second scenario real laser tracker measurements with outliers are adjusted to estimate the parameters of a sphere employing the proposed GHM with VAR and multivariate t-distributed errors. For both scenarios the estimated parameters of the fitted VAR model and multivariate t-distribution are analyzed for evidence of auto- or cross-correlations and deviation from a normal distribution regarding the measurement noise.

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Turbulent three-dimensional dielectric electrohydrodynamic convection between two plates

Journal of Fluid Mechanics ◽

10.1017/jfm.2012.30 ◽

2012 ◽

Vol 696 ◽

pp. 228-262 ◽

Cited By ~ 24

Author(s):

A. Kourmatzis ◽

J. S. Shrimpton

Keyword(s):

Spatial Data ◽

Three Dimensional ◽

Reynolds Numbers ◽

Two Dimensions ◽

Three Dimensions ◽

Energy Budgets ◽

Turbulent Regime ◽

Scalar Flux ◽

Wide Range ◽

Scalar Variance

AbstractThe fundamental mechanisms responsible for the creation of electrohydrodynamically driven roll structures in free electroconvection between two plates are analysed with reference to traditional Rayleigh–Bénard convection (RBC). Previously available knowledge limited to two dimensions is extended to three-dimensions, and a wide range of electric Reynolds numbers is analysed, extending into a fully inherently three-dimensional turbulent regime. Results reveal that structures appearing in three-dimensional electrohydrodynamics (EHD) are similar to those observed for RBC, and while two-dimensional EHD results bear some similarities with the three-dimensional results there are distinct differences. Analysis of two-point correlations and integral length scales show that full three-dimensional electroconvection is more chaotic than in two dimensions and this is also noted by qualitatively observing the roll structures that arise for both low (${\mathit{Re}}_{E} = 1$) and high electric Reynolds numbers (up to ${\mathit{Re}}_{E} = 120$). Furthermore, calculations of mean profiles and second-order moments along with energy budgets and spectra have examined the validity of neglecting the fluctuating electric field ${ E}_{i}^{\ensuremath{\prime} } $ in the Reynolds-averaged EHD equations and provide insight into the generation and transport mechanisms of turbulent EHD. Spectral and spatial data clearly indicate how fluctuating energy is transferred from electrical to hydrodynamic forms, on moving through the domain away from the charging electrode. It is shown that ${ E}_{i}^{\ensuremath{\prime} } $ is not negligible close to the walls and terms acting as sources and sinks in the turbulent kinetic energy, turbulent scalar flux and turbulent scalar variance equations are examined. Profiles of hydrodynamic terms in the budgets resemble those in the literature for RBC; however there are terms specific to EHD that are significant, indicating that the transfer of energy in EHD is also attributed to further electrodynamic terms and a strong coupling exists between the charge flux and variance, due to the ionic drift term.

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Is contact angle a cause or an effect? – A cautionary tale

E3S Web of Conferences ◽

10.1051/e3sconf/202014603004 ◽

2020 ◽

Vol 146 ◽

pp. 03004

Author(s):

Douglas Ruth

Keyword(s):

Contact Angle ◽

Solid Surface ◽

Contact Angles ◽

Two Dimensions ◽

Experimental Results ◽

Flow In Porous Media ◽

Two Dimensional ◽

Wide Range ◽

Fluid Drop ◽

Surrounding Fluid

The most influential parameter on the behavior of two-component flow in porous media is “wettability”. When wettability is being characterized, the most frequently used parameter is the “contact angle”. When a fluid-drop is placed on a solid surface, in the presence of a second, surrounding fluid, the fluid-fluid surface contacts the solid-surface at an angle that is typically measured through the fluid-drop. If this angle is less than 90°, the fluid in the drop is said to “wet” the surface. If this angle is greater than 90°, the surrounding fluid is said to “wet” the surface. This definition is universally accepted and appears to be scientifically justifiable, at least for a static situation where the solid surface is horizontal. Recently, this concept has been extended to characterize wettability in non-static situations using high-resolution, two-dimensional digital images of multi-component systems. Using simple thought experiments and published experimental results, many of them decades old, it will be demonstrated that contact angles are not primary parameters – their values depend on many other parameters. Using these arguments, it will be demonstrated that contact angles are not the cause of wettability behavior but the effect of wettability behavior and other parameters. The result of this is that the contact angle cannot be used as a primary indicator of wettability except in very restricted situations. Furthermore, it will be demonstrated that even for the simple case of a capillary interface in a vertical tube, attempting to use simply a two-dimensional image to determine the contact angle can result in a wide range of measured values. This observation is consistent with some published experimental results. It follows that contact angles measured in two-dimensions cannot be trusted to provide accurate values and these values should not be used to characterize the wettability of the system.

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TETRASPORE is required for male meiotic cytokinesis in Arabidopsis thaliana

Development ◽

10.1242/dev.124.13.2645 ◽

1997 ◽

Vol 124 (13) ◽

pp. 2645-2657 ◽

Cited By ~ 5

Author(s):

M. Spielman ◽

D. Preuss ◽

F.L. Li ◽

W.E. Browne ◽

R.J. Scott ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Pollen Development ◽

Male Meiosis ◽

Pollen Grain ◽

Flowering Plants ◽

External Wall ◽

Normal Pollen ◽

Wide Range ◽

Asymmetric Divisions ◽

And Function

In flowering plants, male meiosis occurs in the microsporocyte to produce four microspores, each of which develops into a pollen grain. Here we describe four mutant alleles of TETRASPORE (TES), a gene essential for microsporocyte cytokinesis in Arabidopsis thaliana. Following failure of male meiotic cytokinesis in tes mutants, all four microspore nuclei remain within the same cytoplasm, with some completing their developmental programmes to form functional pollen nuclei. Both of the mitotic divisions seen in normal pollen development take place in tes mutants, including the asymmetric division required for the differentiation of gametes; some tes grains perform multiple asymmetric divisions in the same cytoplasm. tes pollen shows a variety of abnormalities subsequent to the cytokinetic defect, including fusion of nuclei, formation of ectopic internal walls, and disruptions to external wall patterning. In addition, ovules fertilized by tes pollen often abort, possibly because of excess paternal genomes in the endosperm. Thus tes mutants not only reveal a gene specific to male meiosis, but aid investigation of a wide range of processes in pollen development and function.

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Emphatic Sentences: A Comparative-Translational Study of Formal-Functional Relations in English and Romanian

Transilvania ◽

10.51391/trva.2021.04.10. ◽

2021 ◽

pp. 75-84

Author(s):

Mona Arhire

Keyword(s):

Target Language ◽

Original Text ◽

John Fowles ◽

Translational Study ◽

Form And Function ◽

Functional Relations ◽

Wide Range ◽

Research Questions ◽

And Function ◽

Stylistic Device

Emphasis, a well-acknowledged stylistic device, is a carrier of a considerable load of emotional content in the fictional dialogue. Its manifestation can take sundry forms and can be attached to a wide range of feelings and can take different degrees of intensity, all of which determines the creation of the atmosphere and impacts the reception by the readership. This paper reports on the investigation of the occurrence of emphasis embedded in the dialogic utterances of John Fowles’ novel Mantissa. The focus lies on the relation between the formal construction of emphatic sentences and the functional values deriving therefrom. The study entails a comparative analysis of emphatic utterances depicted from the English original text and its translation into Romanian. The three research questions refer to the comparative-contrastive realization of emphatic sentences in the two languages, to the extent to which the functional component succeeds in being transferred to the target language and to possible means of compensation when structural differences pose translational problems. The analysis is structured along a typology of sentences adapted to the nature of the text under scrutiny and to the aims of this study. The findings and conclusions ultimately indicate the importance of establishing a relation between form and function in matter of emphasis in the literary dialogue as an act of communication depending on linguistic devices for its effectiveness.

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Sub-seasonal Variability in the Boundary Layer Sources for Transport into the Tropopause Layer in the Asian Monsoon Region

10.5194/acp-2017-216 ◽

2017 ◽

Author(s):

Bin Chen ◽

Bärbel Vogel ◽

Xiangde Xu ◽

Shuai Yang

Keyword(s):

Boundary Layer ◽

Tibetan Plateau ◽

Mass Transport ◽

Seasonal Variability ◽

The Tibetan Plateau ◽

Southern Slope ◽

Seasonal Behavior ◽

Air Mass ◽

Source Regions ◽

Wide Range

Abstract. The Asian summer monsoon (ASM) is associated with an upper-level anticyclone and acts as a well-recognized conduit for troposphere-to-stratosphere transport. The Lagrangian dispersion and transport model FLEXPART forced by ERA-Interim data from 2001–2013 was used to perform climatological modeling of the summer season (May–July). This study examines the properties of the air mass transport from the atmospheric boundary layer (BL) to the tropopause layer (TL), with particular focus on the sub-seasonal variability in the tracer-independent BL sources and the potential controlling mechanisms. The results show that, climatologically, the three most impactful BL source regions are northern India, the Tibetan Plateau, and the southern slope of the Himalayas. These regions are consistent with the locations of sources identified in previous studies. However, upon closer inspection, the different source regions to the BL-to-TL air mass transport are not constant in location or shape and are strongly affected by sub-seasonal variability. The contributions from the Tibetan Plateau are most significant in early May but decrease slightly in mid-May to mid-June. In contrast, the contributions from India and the southern slope of the Himalayas increase dramatically, with peak values occurring in mid-July. Empirical Orthogonal Function (EOF) analysis provides further evidence that the BL sources in the ASM region vary across a wide range of spatiotemporal scales. The sub-seasonal behavior of these BL sources is closely related to the strength of persistent deep convection activity over the northern Bay of Bengal and its neighboring areas.

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