scholarly journals Tissue Mechanical Forces and Evolutionary Developmental Changes Act Through Space and Time to Shape Tooth Morphology and Function

BioEssays ◽  
2018 ◽  
Vol 40 (12) ◽  
pp. 1800140 ◽  
Author(s):  
Zachary T. Calamari ◽  
Jimmy Kuang-Hsien Hu ◽  
Ophir D. Klein
Keyword(s):  
Developmental Changes ◽  
Mechanical Forces ◽  
Tooth Morphology ◽  
Space And Time ◽  
And Function

scholarly journals Mechanosensation and Mechanotransduction by Lymphatic Endothelial Cells Act as Important Regulators of Lymphatic Development and Function

2021 ◽  
Vol 22 (8) ◽  
pp. 3955
Author(s):  
László Bálint ◽  
Zoltán Jakus
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Fate ◽  
Molecular Mechanisms ◽  
Critical Role ◽  
Mechanical Forces ◽  
Lymphatic Endothelial Cells ◽  
Lymphatic Development ◽  
And Function ◽  
The Impact

Our understanding of the function and development of the lymphatic system is expanding rapidly due to the identification of specific molecular markers and the availability of novel genetic approaches. In connection, it has been demonstrated that mechanical forces contribute to the endothelial cell fate commitment and play a critical role in influencing lymphatic endothelial cell shape and alignment by promoting sprouting, development, maturation of the lymphatic network, and coordinating lymphatic valve morphogenesis and the stabilization of lymphatic valves. However, the mechanosignaling and mechanotransduction pathways involved in these processes are poorly understood. Here, we provide an overview of the impact of mechanical forces on lymphatics and summarize the current understanding of the molecular mechanisms involved in the mechanosensation and mechanotransduction by lymphatic endothelial cells. We also discuss how these mechanosensitive pathways affect endothelial cell fate and regulate lymphatic development and function. A better understanding of these mechanisms may provide a deeper insight into the pathophysiology of various diseases associated with impaired lymphatic function, such as lymphedema and may eventually lead to the discovery of novel therapeutic targets for these conditions.

Image- and Numerics-Based Analysis of Constitutive Properties of Cellular Structures

2007 ◽  
Author(s):  
Evgeny Gladilin ◽  
Roland Eils
Keyword(s):  
Cell Structure ◽  
Main Idea ◽  
Malignant Cell ◽  
Mechanical Forces ◽  
Material Constants ◽  
Deformation State ◽  
Continuous Description ◽  
External Forces ◽  
And Function ◽  
Optimal Set

External forces, cell adhesion and soluble signaling molecules influence fundamental functions of cells like shape, migration, proliferation or differentiation. Thus, investigating how mechanical forces affect 3D cell structure and function is of crucial significance in order to gain a better understanding healthy and malignant cell behavior during embryogenesis, regeneration or malignancy [1]. Micromanipulation of cells in a controlled environment is a widely used approach for understanding cellular responses with respect to external mechanical forces. While experimental data provide optical information about the overall cell shape, the 3D deformation state of intracellular structures is not accessible by direct observations and measurements. However, the continuous description of the intracellular deformation state can be calculated as a numerical solution of the boundary value problem given by the partial differential equations of structural mechanics, including a set of canonic material constants (stiffness, compressibility), and the boundary conditions derived from time series of images, e.g. change of visible cell contours. The main idea of our approach is to reformulate the problem of finding optimal modeling parameters as an image registration problem. That is the optimal set of modeling parameters corresponds to the minimum of a suitable similarity measure between computationally predicted and experimentally observed deformations. In this article, we focus on the numerical analysis of uniaxial stretching of a rat embryonic fibroblast 52 (REF 52) based on a series of 2D images reflecting the successive alteration of cell contours during deformation. The goal of this study consists in finding an optimal set of material constants within a non-linear hyperelastic material law, which is able to reproduce results of experimental observations.

scholarly journals Mechanical Forces in the Skin: Roles in Tissue Architecture, Stability, and Function

2020 ◽  
Vol 140 (2) ◽  
pp. 284-290 ◽  
Author(s):  
Leah C. Biggs ◽  
Christine S. Kim ◽  
Yekaterina A. Miroshnikova ◽  
Sara A. Wickström
Keyword(s):  
Mechanical Forces ◽  
Tissue Architecture ◽  
And Function

Some aspects of form and function of humor in adolescence

2001 ◽  
Vol 14 (1) ◽  
Author(s):  
Martin Führ
Keyword(s):  
Social Interaction ◽  
Problem Solving ◽  
Developmental Changes ◽  
Sense Of Humor ◽  
Form And Function ◽  
And Function ◽  
Town Area

AbstractThis study investigates the use, form and function of humor for children aged 12–16 years in two different schools including 47 participants through interviews and 112 participants in a questionnaire. The assumption is made, that developmental changes in form and function of humor for children aged 12–13 years may be influenced by their actual environmental settings and their actual tasks. Data from 12–16 year old children from two schools (school 1, in the countryside with grade 1 to 7 and school 2 in an town area with grade 1 to 10) is analyzed to see whether adult humor appears at an earlier stage in school 1. Finally, the study considers the importance of children's sense of humor in problem solving and social interaction during the period 12–16 years.

scholarly journals Propensity of undulatory swimmers, such as worms, to go against the flow

2015 ◽  
Vol 112 (12) ◽  
pp. 3606-3611 ◽  
Author(s):  
Jinzhou Yuan ◽  
David M. Raizen ◽  
Haim H. Bau
Keyword(s):  
Control Strategies ◽  
Aquatic Organisms ◽  
Life Cycles ◽  
Environmental Cues ◽  
Mechanical Forces ◽  
C Elegans ◽  
The Subject ◽  
And Function ◽  
First Time

The ability to orient oneself in response to environmental cues is crucial to the survival and function of diverse organisms. One such orientation behavior is the alignment of aquatic organisms with (negative rheotaxis) or against (positive rheotaxis) fluid current. The questions of whether low-Reynolds-number, undulatory swimmers, such as worms, rheotax and whether rheotaxis is a deliberate or an involuntary response to mechanical forces have been the subject of conflicting reports. To address these questions, we use Caenorhabditis elegans as a model undulatory swimmer and examine, in experiment and theory, the orientation of C. elegans in the presence of flow. We find that when close to a stationary surface the animal aligns itself against the direction of the flow. We elucidate for the first time to our knowledge the mechanisms of rheotaxis in worms and show that rheotaxis can be explained solely by mechanical forces and does not require sensory input or deliberate action. The interaction between the flow field induced by the swimmer and a nearby surface causes the swimmer to tilt toward the surface and the velocity gradient associated with the flow rotates the animal to face upstream. Fluid mechanical computer simulations faithfully mimic the behavior observed in experiments, supporting the notion that rheotaxis behavior can be fully explained by hydrodynamics. Our study highlights the important role of hydrodynamics in the behavior of small undulating swimmers and may assist in developing control strategies to affect the animals’ life cycles.

scholarly journals Aesthetic and functional rehabilitation of a supernumerary peg-shaped tooth in the primary dentition

2014 ◽  
Vol 62 (2) ◽  
pp. 191-195
Author(s):  
Débora KOURI ◽  
Carla Andréia Veiga BERTAIA ◽  
Rossimary Coelho de Freitas SANTOS ◽  
Patrícia Xavier da COSTA-NOBRE ◽  
Eliane Silveira GARCIA-LEITE ◽  
...  
Keyword(s):  
Invasive Procedure ◽  
Self Esteem ◽  
Developmental Changes ◽  
Facial Growth ◽  
Supernumerary Teeth ◽  
Functional Rehabilitation ◽  
System A ◽  
And Function ◽  
Cotton Roll ◽  
Maxillary Region

Supernumerary teeth are common changes in the human dentition that can compromise a congruous dental and facial growth and development. Early diagnosis and proper treatment of these developmental changes are essential for establishing occlusal, functional, and aesthetic congruence. Thus, this article reports the functional and aesthetic rehabilitation of a supernumerary peg-shaped tooth located in the anterior maxillary region of a preschooler. The tooth was restored directly using nanocomposite resin system, a putty index of the incisal position, and modified cotton roll isolation. This minimally invasive procedure not only allows future adjustment but also perfect control of the rehabilitation and simultaneous reestablishment of the child's self-esteem and tooth aesthetics and function. However, treatment should not be limited to the restorative technique. Maintenance of oral health and arch integrity are essential for the correct transition between the primary and permanent dentitions, preventing the treatment from affecting the permanent dentition.

scholarly journals Evolution of Genre Parameters of Documentary Text (Exemplified by References)

2021 ◽  
pp. 134-145
Author(s):  
Olga Nosacheva ◽  
Keyword(s):  
Information Structure ◽  
Soviet Period ◽  
Social Changes ◽  
Time Representation ◽  
Space And Time ◽  
And Function ◽  
Function Information ◽  
Text Formation ◽  
Functional Purpose

The article considers reference as an information-and-assessment document, the dynamics of reference transformation is viewed from documentary linguistics angle. The research is carried out on the material of reference given to applicants in the field of education; the documents belong to different chronological periods (Soviet period (wartime): 1941–1945; Soviet period: 1970–1990s; modern period: 2015–2020). The functional purpose of the document was determined and the composition and content structure of its text was analyzed. Speech means representing the main genre characteristics of the text of reference have been identified; they are presented at three levels of the hierarchy, taking into account their interconnection and significance as genre-forming parameters: addresser/addressee and function; information, structure and dominant modality; space and time. The author reveals the regularities of text formation, as well as genre peculiarities of the text, determined by social and linguistic factors. When analyzing the genre parameters of the document, the fact that the properties of the text are influenced by the specifics of the communication situation is taken into account. It was shown that social changes caused a shift in the nature of the information transmitted by the document; affected the structure and dominant modality of the text, space and time representation. Extralinguistic determination of speech organization of documentary text is demonstrated. It was established that speech representation of genre parameters is associated with the implementation of informational and presentation functions of the document.

Nanoscale Analysis of the Effect of Pathogenic Mutations on Polycystin-1

2010 ◽  
Author(s):  
Liang Ma ◽  
Meixiang Xu ◽  
Andres F. Oberhauser
Keyword(s):  
Single Molecule ◽  
Conformational Changes ◽  
Protein Interactions ◽  
Structure And Function ◽  
Eukaryotic Cells ◽  
Mechanical Forces ◽  
Force Microscopy ◽  
Physiological Conditions ◽  
Atomic Force ◽  
And Function

The activity of proteins and their complexes often involves the conversion of chemical energy (stored or supplied) into mechanical work through conformational changes. Mechanical forces are also crucial for the regulation of the structure and function of cells and tissues. Thus, the shape of eukaryotic cells is the result of cycles of mechano-sensing, mechano-transduction, and mechano-response. Recently developed single-molecule atomic force microscopy (AFM) techniques can be used to manipulate single molecules, both in real time and under physiological conditions, and are ideally suited to directly quantify the forces involved in both intra- and intermolecular protein interactions. In combination with molecular biology and computer simulations, these techniques have been applied to characterize the unfolding and refolding reactions in a variety of proteins, such as titin (an elastic mechano-sensing protein found in muscle) and polycystin-1 (PC1, a mechanosensor found in the kidney).

scholarly journals ’n Ondersoek na die identifisering van deiktiese ruimte in die prosa

Literator ◽  
2003 ◽  
Vol 24 (1) ◽  
pp. 125-144
Author(s):  
J. Anker
Keyword(s):  
Literary Texts ◽  
Abstract Author ◽  
Space And Time ◽  
And Function ◽  
The Mind ◽  
Role And Function

The role and function of deictic context in a prose text This article examines the nature and function of deictics in a prose text. By referring to different theories of pragmatics and literature, the nature of communication in literary texts and the role that deixis plays in these texts become evident. In a prose text a process of communication exists in which the utterance produced by the speaker (author) is interpreted by a hearer (reader). The reader reconstructs a context for this communication by the interpretation of the speaker’s references to person, place and time – the deictic elements. The reader determines the deictic context in a text by defining and interpreting the communication of the abstract author, the different speaker’s references to persons, space and time and by interpreting the implications in the linguistic utterance. In this way a deictic context is formed in the mind of the reader which forms the basis for his understanding of the message in the text.

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