The Axes of Symmetry. Morphology in Aristotle’s Biology

Apeiron ◽  
2016 ◽  
Vol 49 (1) ◽  
pp. 1-31 ◽  
Author(s):  
Andrea L. Carbone
Keyword(s):  
Research Program ◽  
Body Plan ◽  
The Body ◽  
Mathematical Approach ◽  
Methodological Framework ◽  
Important Principle ◽  
Living Things ◽  
Biology I ◽  
Definition Of ◽  
Axes Of Symmetry

AbstractMy aim in this paper is to outline and discuss the role played in Aristotle’s inquiry into living things by his extensive comparative account of the body plan of different kinds of animals, and of the shapes and figures of their bodily parts, which we may call his morphology. In tackling this question, I begin with Aristotle’s statement that the diagrammatical representation of the body’s organization based on the axes of symmetry is the second most important principle of the inquiry on living things, after the teleology principle. I discuss, in turn, his concern about the applicability of the mathematical approach to the living shapes; his analysis of the ways in which form is related to limit; and his criticism of Democritus’ and Empedocles’ treatment of form and shape. Through exploring the ways in which Aristotle recurs to the morphology principle in the practice of biology, I point out that morphology provides a key methodological framework for the two most important tasks of the research program of the inquiry on living things – the definition of the kinds and the explanation of the causes.

Homeostasis: getting a balance

2020 ◽  
Vol 14 (7) ◽  
pp. 330-335 ◽  
Author(s):  
Ian Peate
Keyword(s):  
Building Blocks ◽  
The Body ◽  
Internal Environment ◽  
Self Assessment ◽  
Anatomy And Physiology ◽  
Living Things ◽  
Definition Of ◽  
Insight Into ◽  
Healthcare Assistant ◽  
Assistant Practitioner

The healthcare assistant and assistant practitioner (HCA and AP) must have an understating of how the body works and how it functions in both illness and in health, so as to offer people care that is safe, effective and person-centred. This series of articles offers the HCA and AP an understanding of how the human body works: its anatomy and physiology. The first article of this series ( Peate, 2020 ) provided insight into the terminology used in anatomy. This article focuses on homeostasis, how it is that the body maintains a stable internal environment regardless of the changes that occur externally. The third article considers the cells, which are the basic building blocks of all living things. The rest of the series considers each of the body's systems in turn. In this article, a definition of homeostasis is provided and examples are discussed as to how the body maintains homeostasis. The article ends with a glossary of terms and set of questions used as self-assessment.

Derrida on Pornography: Putting (It) Up for Sale

Derrida Today ◽  
2013 ◽  
Vol 6 (1) ◽  
pp. 97-114 ◽  
Author(s):  
Christopher Morris
Keyword(s):  
Cultural Studies ◽  
English Translation ◽  
The Body ◽  
The Past ◽  
French Original ◽  
Definition Of ◽  
Critical Discourses ◽  
Academic Debate

Over the past thirty years, academic debate over pornography in the discourses of feminism and cultural studies has foundered on questions of the performative and of the word's definition. In the polylogue of Droit de regards, pornography is defined as la mise en vente that is taking place in the act of exegesis in progress. (Wills's idiomatic English translation includes an ‘it’ that is absent in the French original). The definition in Droit de regards alludes to the word's etymology (writing by or about prostitutes) but leaves the referent of the ‘sale’ suspended. Pornography as la mise en vente boldly restates the necessary iterability of the sign and anticipates two of Derrida's late arguments: that there is no ‘the’ body and that performatives may be powerless. Deriving a definition of pornography from a truncated etymology exemplifies the prosthesis of origin and challenges other critical discourses to explain how pornography can be understood as anything more than ‘putting (it) up for sale’.

The specifics of mergers and acquisitions of innovative and technological companies

2020 ◽  
Vol 26 (5) ◽  
pp. 1186-1204
Author(s):  
A.V. Fedorov ◽  
Zh.S. Peredera
Keyword(s):  
Digital Technology ◽  
Comprehensive Analysis ◽  
Methodological Framework ◽  
Comparison Study ◽  
Technology Sector ◽  
Theoretical Perspectives ◽  
Innovation And Technology ◽  
Set Up ◽  
Definition Of ◽  
Traditional Approaches

Subject. The article reviews distinctions of M&A deals in innovation and technology. Objectives. We determine the specifics of innovative and technological companies and its impact on the synergy, process, finance, valuation of M&A deals. Methods. The article employs methods of generalization, comprehensive analysis, systematization, specification, comparison, study into trends and the structure. Graphics and tables are used to display the findings. Results. We conducted the content analysis of the term Mergers & Acquisitions, thus finding the divergence of foreign and the Russian approaches. We provide our own definition of the concept and analyzed the dynamics of the overall M&A market and the innovation and technological sector. The article describes operational distinctions of innovative and technological companies and compares them with conventional sectors. The article determined the specifics of synergy, process, finance, valuation of M&A deals in innovation and technology. Conclusions and Relevance. The innovation and technology sector saw M&A deals become more frequent for the recent five years. What distinguishes them is the number of startups and infant businesses, large M&A deals in order to develop their ecosystems, involve digital technology companies. Traditional approaches should be adapted for structuring M&A deals, their arrangement, financing and valuation of target companies. The findings can lay the groundwork for further studies into the specifics of the innovation and technology sector, M&A deals, and set up the methodological framework for the valuation of innovative and technological companies. The findings can also immediately support parties of M&A deals from theoretical perspectives.

scholarly journals Expression patterns of signalling molecules and transcription factors in the early rabbit embryo and their significance for modelling amniote axis formation

2021 ◽  
Author(s):  
Ruben Plöger ◽  
Christoph Viebahn
Keyword(s):  
Transcription Factors ◽  
Expression Patterns ◽  
In Situ Hybridisation ◽  
Body Plan ◽  
The Body ◽  
Anchor Point ◽  
Axis Formation ◽  
Point Model ◽  
Signalling Molecules ◽  
Rabbit Embryo

AbstractThe anterior-posterior axis is a central element of the body plan and, during amniote gastrulation, forms through several transient domains with specific morphogenetic activities. In the chick, experimentally proven activity of signalling molecules and transcription factors lead to the concept of a ‘global positioning system’ for initial axis formation whereas in the (mammotypical) rabbit embryo, a series of morphological or molecular domains are part of a putative ‘three-anchor-point model’. Because circular expression patterns of genes involved in axis formation exist in both amniote groups prior to, and during, gastrulation and may thus be suited to reconcile these models, the expression patterns of selected genes known in the chick, namely the ones coding for the transcription factors eomes and tbx6, the signalling molecule wnt3 and the wnt inhibitor pkdcc, were analysed in the rabbit embryonic disc using in situ hybridisation and placing emphasis on their germ layer location. Peripheral wnt3 and eomes expression in all layers is found initially to be complementary to central pkdcc expression in the hypoblast during early axis formation. Pkdcc then appears — together with a posterior-anterior gradient in wnt3 and eomes domains — in the epiblast posteriorly before the emerging primitive streak is marked by pkdcc and tbx6 at its anterior and posterior extremities, respectively. Conserved circular expression patterns deduced from some of this data may point to shared mechanisms in amniote axis formation while the reshaping of localised gene expression patterns is discussed as part of the ‘three-anchor-point model’ for establishing the mammalian body plan.

scholarly journals Petiole-Lamina Transition Zone: A Functionally Crucial but Often Overlooked Leaf Trait

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 774
Author(s):  
Max Langer ◽  
Thomas Speck ◽  
Olga Speck
Keyword(s):  
Transition Zone ◽  
Three Dimensional ◽  
Spatial Arrangement ◽  
Body Plan ◽  
The Body ◽  
Vascular Bundles ◽  
Cross Sectional ◽  
Thin Sections ◽  
Transition Zones ◽  
The Cross

Although both the petiole and lamina of foliage leaves have been thoroughly studied, the transition zone between them has often been overlooked. We aimed to identify objectively measurable morphological and anatomical criteria for a generally valid definition of the petiole–lamina transition zone by comparing foliage leaves with various body plans (monocotyledons vs. dicotyledons) and spatial arrangements of petiole and lamina (two-dimensional vs. three-dimensional configurations). Cross-sectional geometry and tissue arrangement of petioles and transition zones were investigated via serial thin-sections and µCT. The changes in the cross-sectional geometries from the petiole to the transition zone and the course of the vascular bundles in the transition zone apparently depend on the spatial arrangement, while the arrangement of the vascular bundles in the petioles depends on the body plan. We found an exponential acropetal increase in the cross-sectional area and axial and polar second moments of area to be the defining characteristic of all transition zones studied, regardless of body plan or spatial arrangement. In conclusion, a variety of terms is used in the literature for describing the region between petiole and lamina. We prefer the term “petiole–lamina transition zone” to underline its three-dimensional nature and the integration of multiple gradients of geometry, shape, and size.

scholarly journals Zur exakten Behandlung von kollektiven Rotationen Teil A: Theorie / On the Exact Treatment of Collective Rotations Part A: Theory

1973 ◽  
Vol 28 (2) ◽  
pp. 206-215
Author(s):  
Hanns Ruder
Keyword(s):  
Coordinate System ◽  
Perturbation Expansion ◽  
Rotational Energy ◽  
The Body ◽  
System A ◽  
N Body Problem ◽  
Definition Of ◽  
Fixed System ◽  
Body Fixed Coordinate System ◽  
Groundstate Energy

Basic in the treatment of collective rotations is the definition of a body-fixed coordinate system. A kinematical method is derived to obtain the Hamiltonian of a n-body problem for a given definition of the body-fixed system. From this exact Hamiltonian, a consequent perturbation expansion in terms of the total angular momentum leads to two exact expressions: one for the collective rotational energy which has to be added to the groundstate energy in this order of perturbation and a second one for the effective inertia tensor in the groundstate. The discussion of these results leads to two criteria how to define the best body-fixed coordinate system, namely a differential equation and a variational principle. The equivalence of both is shown.

scholarly journals Spiritual nursing care: A concept analysis

Curationis ◽  
2012 ◽  
Vol 35 (1) ◽  
Author(s):  
Lydia V. Monareng
Keyword(s):  
Nursing Care ◽  
Concept Analysis ◽  
Operational Definition ◽  
The Body ◽  
Empirical Literature ◽  
Spiritual Needs ◽  
Optimal Care ◽  
Health Crisis ◽  
Group Interviews ◽  
Definition Of

Although the concept ‘spiritual nursing care’ has its roots in the history of the nursing profession, many nurses in practice have difficulty integrating the concept into practice. There is an ongoing debate in the empirical literature about its definition, clarity and application in nursing practice. The study aimed to develop an operational definition of the concept and its application in clinical practice. A qualitative study was conducted to explore and describe how professional nurses render spiritual nursing care. A purposive sampling method was used to recruit the sample. Individual and focus group interviews were audio-taped and transcribed verbatim. Trustworthiness was ensured through strategies of truth value, applicability, consistency and neutrality. Data were analysed using the NUD*IST power version 4 software, constant comparison, open, axial and selective coding. Tech’s eight steps of analysis were also used, which led to the emergence of themes, categories and sub-categories. Concept analysis was conducted through a comprehensive literature review and as a result ‘caring presence’ was identified as the core variable from which all the other characteristics of spiritual nursing care arise. An operational definition of spiritual nursing care based on the findings was that humane care is demonstrated by showing caring presence, respect and concern for meeting the needs not only of the body and mind of patients, but also their spiritual needs of hope and meaning in the midst of health crisis, which demand equal attention for optimal care from both religious and nonreligious nurses.

scholarly journals Scalable co-optimization of morphology and control in embodied machines

2018 ◽  
Vol 15 (143) ◽  
pp. 20170937 ◽  
Author(s):  
Nick Cheney ◽  
Josh Bongard ◽  
Vytas SunSpiral ◽  
Hod Lipson
Keyword(s):  
Embodied Cognition ◽  
Initial Conditions ◽  
Control Policy ◽  
Sensorimotor Control ◽  
Body Plan ◽  
The Body ◽  
Test Bed ◽  
Local Optima ◽  
Close Coupling ◽  
And Control

Evolution sculpts both the body plans and nervous systems of agents together over time. By contrast, in artificial intelligence and robotics, a robot's body plan is usually designed by hand, and control policies are then optimized for that fixed design. The task of simultaneously co-optimizing the morphology and controller of an embodied robot has remained a challenge. In psychology, the theory of embodied cognition posits that behaviour arises from a close coupling between body plan and sensorimotor control, which suggests why co-optimizing these two subsystems is so difficult: most evolutionary changes to morphology tend to adversely impact sensorimotor control, leading to an overall decrease in behavioural performance. Here, we further examine this hypothesis and demonstrate a technique for ‘morphological innovation protection’, which temporarily reduces selection pressure on recently morphologically changed individuals, thus enabling evolution some time to ‘readapt’ to the new morphology with subsequent control policy mutations. We show the potential for this method to avoid local optima and converge to similar highly fit morphologies across widely varying initial conditions, while sustaining fitness improvements further into optimization. While this technique is admittedly only the first of many steps that must be taken to achieve scalable optimization of embodied machines, we hope that theoretical insight into the cause of evolutionary stagnation in current methods will help to enable the automation of robot design and behavioural training—while simultaneously providing a test bed to investigate the theory of embodied cognition.

scholarly journals A global framework for a systemic view of brain modeling

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Frederic Alexandre
Keyword(s):  
Instrumental Conditioning ◽  
The Body ◽  
Posterior Cortex ◽  
Reciprocal Relationships ◽  
Brain Modeling ◽  
Brain Theory ◽  
Habitual Behavior ◽  
Definition Of ◽  
The Brain ◽  
Specific Contribution

AbstractThe brain is a complex system, due to the heterogeneity of its structure, the diversity of the functions in which it participates and to its reciprocal relationships with the body and the environment. A systemic description of the brain is presented here, as a contribution to developing a brain theory and as a general framework where specific models in computational neuroscience can be integrated and associated with global information flows and cognitive functions. In an enactive view, this framework integrates the fundamental organization of the brain in sensorimotor loops with the internal and the external worlds, answering four fundamental questions (what, why, where and how). Our survival-oriented definition of behavior gives a prominent role to pavlovian and instrumental conditioning, augmented during phylogeny by the specific contribution of other kinds of learning, related to semantic memory in the posterior cortex, episodic memory in the hippocampus and working memory in the frontal cortex. This framework highlights that responses can be prepared in different ways, from pavlovian reflexes and habitual behavior to deliberations for goal-directed planning and reasoning, and explains that these different kinds of responses coexist, collaborate and compete for the control of behavior. It also lays emphasis on the fact that cognition can be described as a dynamical system of interacting memories, some acting to provide information to others, to replace them when they are not efficient enough, or to help for their improvement. Describing the brain as an architecture of learning systems has also strong implications in Machine Learning. Our biologically informed view of pavlovian and instrumental conditioning can be very precious to revisit classical Reinforcement Learning and provide a basis to ensure really autonomous learning.

The Meaning of Pain and the Pain of Meaning: A Bio-Hermeneutical Inquiry

2021 ◽  
Vol 90 ◽  
pp. 215-234
Author(s):  
Teodora Manea
Keyword(s):  
The Body ◽  
Main Interest ◽  
Main Approach ◽  
Memento Mori ◽  
Finding Meaning ◽  
Pace Of Life ◽  
Before And After ◽  
Definition Of

AbstractMy main interest here is to look at pain as a sign of the body that something is wrong. I will argue that there is a meaning of pain before and after an illness is diagnosed. An illness contains its own semantic paradigm, but the pain before the diagnosis affects the pace of life, not only by limiting our interactions, but also as a struggle with its meaning and a reminder of mortality.My main approach is what I call bio-hermeneutics, an extension of medical hermeneutics branching out from the Continental hermeneutical tradition. As such, I will explore the connection between pain and language, temporality, dialectics, and ontology. Given the centrality of language in constructing the meaning of pain, my analysis is informed by the semantics (looking at pain metaphors), syntax (pain as incoherence), and pragmatics (pain as companion) of expressing pain.The last section explores the meaning of pain in connection with death, as memento mori. Revisiting an old definition of philosophy as melete thanatou, or ‘rehearsal of death’, I will reflect on the difficulty of finding meaning not only for pain, but also for death as cessation of all existential possibilities.

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