How the foot and ankle works (mechanics of the foot)

2021 ◽  
pp. 661-664
Author(s):  
Ian Winson
Keyword(s):  
Muscle Tension ◽  
Dynamic Structure ◽  
Foot And Ankle ◽  
Complex Dynamic ◽  
Shock Absorption ◽  
Axis Of Rotation ◽  
Muscle Balance ◽  
Balanced Structure

This chapter examines the mechanics of the foot from the clinician’s perspective. The kinematics, kinetics, muscle balance, and stability of the foot and ankle are complex, as the foot has evolved to provide shock absorption, stability, propulsion, and accommodation. It does this by maintaining a stable, balanced structure in all positions of the foot. The mobility of the joints together with their stabilizing structures (the ligaments of the foot), and the complex balance between muscle tension and tendon position relative to the axis of rotation of the joints, are responsible for this function. As a consequence of this complex dynamic structure, the foot stores a significant amount of energy during ambulation, and its efficient use of this is a major reason for the ability of humans to travel long distances.

scholarly journals The Solid Tumor Microenvironment - Breaking The Barrier For T Cells

2021 ◽  
Author(s):  
Hasan Simsek ◽  
Enrico Klotzsch
Keyword(s):  
T Cells ◽  
Tumor Microenvironment ◽  
Tumor Tissue ◽  
Fluid Pressure ◽  
Dynamic Structure ◽  
Surrounding Tissue ◽  
Cellular Functions ◽  
Complex Dynamic ◽  
Vascular Structures ◽  
Physical Interactions

The tumor microenvironment plays a pivotal role in the behavior and development of solid tumors as well as shaping the immune response against them. As the tumor cells proliferate, the space they occupy and their physical interactions with the surrounding tissue increases. The growing tumor tissue becomes a complex dynamic structure, containing connective tissue, vascular structures, and extracellular matrix that facilitates stimulation, oxygenation, and nutrition, necessary for its fast growth. Mechanical cues such as stiffness, solid stress, interstitial fluid pressure, matrix density, and microarchitecture influence cellular functions and ultimately tumor progression and metastasis. In this fight, our body is equipped with T cells as its spearhead against tumors. However, the altered biochemical and mechanical environment of the tumor niche affects T cell efficacy and leads to their exhaustion. Understanding the mechanobiological properties of the tumor microenvironment and their effects on T cells is key for developing novel adoptive tumor immunotherapies.

Dynamics Characteristic of a Linear Oscillator with Nonlinear Damped Attachment as Energy Absorber

2010 ◽  
Vol 44-47 ◽  
pp. 2651-2655 ◽  
Author(s):  
Jian Lian Cheng
Keyword(s):  
Numerical Analysis ◽  
Nonlinear System ◽  
Periodic Orbits ◽  
Dynamic Structure ◽  
Nonlinear Stiffness ◽  
Complex Dynamic ◽  
Energy Absorber ◽  
Energy Pumping ◽  
Two Degree Of Freedom ◽  
Dynamics Characteristic

The dynamics of a two-degree-of-freedom (2-DOF) nonlinear system, consisting of a grounded linear coupled to an attachment by means of an essentially nonlinear stiffness, is studied. The essential nonlinearity of the attachment enable it to resonate with any of the linearized modes of the substructure leading to energy pumping phenomena, irreversible transfer of energy from the substructure to the attachment. We then study analytically the periodic orbits of the system using a complexification/averaging technique in order to determine the frequency contents of the fundamental branches of solutions, and to understand the types of oscillation performed by the system at different regimes of the motion. The results of numerical analysis show complex dynamic structure of the system.

scholarly journals A thousand TV shows : applying a rhizomatic lens to television genres

2018 ◽  
Author(s):  
◽  
Nettie Brock
Keyword(s):  
21St Century ◽  
Dynamic Structure ◽  
Genre Studies ◽  
Television Programs ◽  
Complex Dynamic ◽  
Television Shows ◽  
Way Of Thinking ◽  
Tv Shows ◽  
Cultural Hierarchies ◽  
Meta Theory

One frequent technique for studying television is through genre. However, with the complex television environment of the 21st century, many genre studies do not adequately account for how generic television programs intersect other generic traits. This study probes how genre works within complex television narratives and proposes a new way of thinking about genre. Through Deleuze and Guattari's (1987) theory of the rhizome, I will suggest an interconnected understanding of genre characteristics. The television landscape is a complex, dynamic structure; the assortment of programs and the traits of those programs differ greatly from one moment to the next. Therefore, this study will propose a meta-theory that enables studying this landscape. The theory of the generic rhizome challenges simplistic readings of television texts; opens texts up to endless possible interpretations and insights; and it flattens cultural hierarchies. In two studies, which look at sitcoms and Westerns, I tease out this theory and study television shows in a way that mines, rather than flattens, the complexity of the medium.

scholarly journals Fixed and Dynamic Predictors of Willingness to Communicate in L2: A Review on New Paradigms of Individual Differences

2021 ◽  
Vol 9 (S1-May) ◽  
pp. 154-161
Author(s):  
Ahmet Selçuk Akdemir
Keyword(s):  
Individual Differences ◽  
Dynamic System ◽  
Paradigm Shift ◽  
Dynamic Structure ◽  
Willingness To Communicate ◽  
Complex Nature ◽  
Complex Dynamic ◽  
Basic Principles ◽  
Complex Dynamic System ◽  
Non Linear

Willingness to communicate (WTC), a recent affective construct of SLA research, has experienced a paradigm shift regarding its nature. Current WTC research tends to define it as a dynamic and context-bound structure rather being in a linear and static disposition. New conceptualization is based on Complex Dynamic System (CDS) theory. This theory has been applied to SLA research to explain dynamic, non-linear and complex nature of SLA process. The convenience of CDS theory’s basic principles has led existing WTC structure to be re-shaped and revised to define it as a dynamic structure in contrast to its former definition which would recall WTC as a static and trait-like variable.

The Study on Disturbing Force of Dynamic Mechanical Systems Using Kalman Filter Techniques

2013 ◽  
Vol 705 ◽  
pp. 371-377
Author(s):  
Zhang Jing
Keyword(s):  
Kalman Filter ◽  
Mechanical Systems ◽  
Dynamic Structure ◽  
Estimation Accuracy ◽  
Complex Dynamic ◽  
Model Quality ◽  
Disturbing Force ◽  
Dynamic Mechanical ◽  
Multiple Sensors ◽  
Mems Sensor

According to the approach presented in this paper, the disturbing force of dynamic mechanical systems can be estimated using Kalman Filter techniques. It has been shown how multiple sensors can be included to improve the estimation accuracy and how the algorithm responds to changing parameters and model inaccuracies. Finally, the approach has been experimentally verified with a MEMS-sensor and a more complex dynamic structure of a milling machine with active magnetic guides. Future enhancements may especially regard the model side, since the estimation accuracy is directly determined by the model quality.

scholarly journals Ras plasma membrane signalling platforms

2005 ◽  
Vol 389 (1) ◽  
pp. 1-11 ◽  
Author(s):  
John F. HANCOCK ◽  
Robert G. PARTON
Keyword(s):  
Signal Transduction ◽  
Plasma Membrane ◽  
Cell Signalling ◽  
Dynamic Structure ◽  
Signal Transduction Pathways ◽  
Ras Proteins ◽  
Complex Dynamic ◽  
Additional Level ◽  
Ras Signal Transduction

The plasma membrane is a complex, dynamic structure that provides platforms for the assembly of many signal transduction pathways. These platforms have the capacity to impose an additional level of regulation on cell signalling networks. In this review, we will consider specifically how Ras proteins interact with the plasma membrane. The focus will be on recent studies that provide novel spatial and dynamic insights into the micro-environments that different Ras proteins utilize for signal transduction. We will correlate these recent studies suggesting Ras proteins might operate within a heterogeneous plasma membrane with earlier biochemical work on Ras signal transduction.

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