Categories

2021 ◽  
pp. 1-34
Author(s):  
Niles Johnson ◽  
Donald Yau
Keyword(s):  
Natural Transformation ◽  
Monoidal Categories ◽  
Enriched Categories ◽  
Basic Concepts ◽  
Coherence Theorem ◽  
Yoneda Lemma

In this chapter, categories are defined, and basic concepts are reviewed. Starting from the definitions of a category, a functor, and a natural transformation, the chapter reviews limits, adjunctions, equivalences, the Yoneda Lemma, monads, monoidal categories, and Mac Lane's Coherence Theorem. Enriched categories, which provide one characterization of 2-categories, are also discussed. This chapter makes this book self-contained and accessible to beginners.

A new model system for endometritis: Basic concepts and characterization of phenotypic and functional properties of bovine uterine neutrophils

1996 ◽  
Vol 46 (8) ◽  
pp. 1339-1356 ◽  
Author(s):  
H. Zerbe ◽  
H.-J. Schuberth ◽  
M. Hoedemaker ◽  
E. Grunert ◽  
W. Leibold
Keyword(s):  
Functional Properties ◽  
Model System ◽  
New Model ◽  
Basic Concepts

Relevance and cognitive style: on the double characterization of science in Alfred Schutz

2021 ◽  
pp. 52-68
Author(s):  
Ken Takakusa
Keyword(s):  
Cognitive Style ◽  
Science Studies ◽  
Scientific Activity ◽  
Critical Examination ◽  
Scientific Attitude ◽  
Life World ◽  
Multiple Realities ◽  
Contemporary Science ◽  
Basic Concepts

This paper reveals Schutz's double characterization of science. First, he characterizes science as a modification of interest and relevance. This is compatible with his basic view of science as embedded in the life-world. Second, in contrast, he often excludes working and communication from his argument on science and characterizes science as a pure cogitation. By critically examining the distinction between scientific attitude and scientific activity as well as the concept of cognitive style, this paper concludes that the second characterization proposed by Schutz is untenable. In addition, this paper indicates that the second characterization experienced a significant change from On Multiple Realities to Symbol, Reality, and Society. Although Schutz has been challenged by contemporary science studies because of his ineffectiveness to deal with scientific activity, the careful and critical examination of his argument allows a positive interpretation of his theory as offering basic concepts for the investigation of scientific activity.

Hierarchies

2003 ◽  
pp. 91-115 ◽  
Author(s):  
Elaheh Pourabbas ◽  
Maurizio Rafanelli
Keyword(s):  
Hierarchical Structures ◽  
Different Types ◽  
Basic Concepts ◽  
Points Of View

In this chapter we will focus on the rules of aggregation hierarchies in analysis dimensions of a cube. We give an overview of the related works on the basic concepts of the different types of aggregation hierarchies. We then discuss the hierarchies from two different points of view: mapping between domain values and hierarchical structures. In relation to them, we introduce the characterization of some OLAP operators on hierarchies and give a set of operators that concern the change in the hierarchy structure. Finally, we propose an enlargement of the operator set concerning hierarchies.

The Yoneda Lemma and Coherence

2021 ◽  
pp. 305-330
Author(s):  
Niles Johnson ◽  
Donald Yau
Keyword(s):  
Coherence Theorem ◽  
Local Equivalence ◽  
Yoneda Lemma

In this chapter, the Yoneda Lemma and the Coherence Theorem for bicategories are stated and proved. The chapter discusses the bicategorical Yoneda pseudofunctor, a bicategorical version of the Yoneda embedding for a bicategory, which is a local equivalence, and the Bicategorical Yoneda Lemma. A consequence of the Bicategorical Whitehead Theorem and the Bicategorical Yoneda Embedding is the Bicategorical Coherence Theorem, which states that every bicategory is biequivalent to a 2-category.

scholarly journals Subgroups of quantum groups

2018 ◽  
Vol 70 (2) ◽  
pp. 509-533
Author(s):  
Georgia Christodoulou
Keyword(s):  
Quantum Group ◽  
Quantum Groups ◽  
Homogeneous Spaces ◽  
General Definition ◽  
Monoidal Categories ◽  
Categorical Approach ◽  
Quantum Homogeneous Spaces

Abstract We investigate the notion of a subgroup of a quantum group. We suggest a general definition, which takes into account the work that has been done for quantum homogeneous spaces. We further restrict our attention to reductive subgroups, where some faithful flatness conditions apply. Furthermore, we proceed with a categorical approach to the problem of finding quantum subgroups. We translate all existing results into the language of module and monoidal categories and give another characterization of the notion of a quantum subgroup.

scholarly journals Moral dilemmas in professions of public trust and the assumptions of ethics of social consequences

2016 ◽  
Vol 6 (1-2) ◽  
pp. 19-32 ◽  
Author(s):  
Paulina Dubiel-Zielińska
Keyword(s):  
Moral Dilemmas ◽  
Public Trust ◽  
Daily Basis ◽  
Social Consequences ◽  
General Description ◽  
Moral Dimension ◽  
Basic Concepts ◽  
The Difference ◽  
Definition Of

Abstract The aim of the article is to show the possibility of applying assumptions from ethics of social consequences when making decisions about actions, as well as in situations of moral dilemmas, by persons performing occupations of public trust on a daily basis. Reasoning in the article is analytical and synthetic. Article begins with an explanation of the basic concepts of “profession” and “the profession of public trust” and a manifestation of the difference between these terms. This is followed by a general description of professions of public trust. The area and definition of moral dilemmas is emphasized. Furthermore, representatives of professions belonging to them are listed. After a brief characterization of axiological foundations and the main assumptions of ethics of social consequences, actions according to Vasil Gluchman and Włodzimierz Galewicz are discussed and actions in line with ethics of social consequences are transferred to the practical domain. The article points out that actions in professional life are obligatory, impermissible, permissible, supererogatory and unmarked in the moral dimension. In the final part of the article an afterthought is included on how to solve moral dilemmas when in the position of a representative of the profession of public trust. The article concludes with a summary report containing the conclusions that stem from ethics of social consequences for professions of public trust, followed by short examples.

scholarly journals Detection and Characterization of Autoagglutination Activity by Campylobacter jejuni

2000 ◽  
Vol 68 (11) ◽  
pp. 6168-6175 ◽  
Author(s):  
Naoaki Misawa ◽  
Martin J. Blaser
Keyword(s):  
Campylobacter Jejuni ◽  
Natural Transformation ◽  
Host Cells ◽  
Vitro Assay ◽  
Sodium Metaperiodate ◽  
Bacterial Hydrophobicity ◽  
Phosphate Buffered Saline ◽  
Common Cell

ABSTRACT In several gram-negative bacterial pathogens, autoagglutination (AAG) activity is a marker for interaction with host cells and virulence. Campylobacter jejuni strains also show AAG, but this property varies considerably among strains. To examine the characteristics of C. jejuni AAG, we developed a quantitative in vitro assay. For strain 81-176, which shows high AAG, activity was optimal for cells grown for ≤24 h, was independent of growth temperature, and was best measured for cells suspended in phosphate-buffered saline at 25°C for 24 h. AAG activity was heat labile and was abolished by pronase or acid-glycine (pH 2.2) treatment but not by lipase, DNase, or sodium metaperiodate. Strain 4182 has low AAG activity, but extraction with water increased AAG, suggesting the loss of an inhibitor. Strain 6960 has weak AAG with no effect due to water extraction. Our study with clinical isolates suggests that C. jejuni strains may be grouped into three AAG phenotypes. A variant derived from strain 81116 that is flagellate but immotile showed the strong AAG exhibited by the parent strain, suggesting that motility per se is not necessary for the AAG activity. AAG correlated with both bacterial hydrophobicity and adherence to INT407 cells. Mutants which lack flagella (flaA,flaB, and flbA) or common cell surface antigen (peb1A) were constructed in strain 81-176 by natural transformation-mediated allelic exchange. Both AAG activity and bacterial hydrophobicity were abolished in the aflagellate mutants but not the peb1A mutant. In total, these findings indicate that C. jejuni AAG is highly associated with flagellar expression.

scholarly journals Enriched category as a model of qualia structure based on similarity judgements

2021 ◽  
Author(s):  
Naotsugu Tsuchiya ◽  
Steven Phillips ◽  
Hayato Saigo
Keyword(s):  
Category Theory ◽  
Sorites Paradox ◽  
Perceived Similarity ◽  
Enriched Category ◽  
Enriched Categories ◽  
Important Extension ◽  
Similarity Relationships ◽  
Yoneda Lemma ◽  
Similarity Judgements ◽  
Qualia Structure

Qualitative relationships between two instances of conscious experiences can be quantified through the perceived similarity. Previously, we proposed that by defining similarity relationships as arrows and conscious experiences as objects, we can define a category of qualia in the context of category theory. However, the example qualia categories we proposed were highly idealized and limited to cases where perceived similarity is binary: either present or absent without any gradation. When similarity is graded, a situation can arise where A0 is similar to A1, A1 is similar to A2, and so on, yet A0 is not similar to An, which is called the Sorites paradox. Here, we introduce enriched category theory to address this situation. Enriched categories generalize the concept of a relation between objects as a directed arrow (or morphism) in ordinary category theory to a more flexible notion, such as a measure of distance. As an alternative relation, here we propose a graded measure of perceived dissimilarity between the two objects. These measures combine in a way that addresses the Sorites paradox; even if the dissimilarity between Ai and Ai+1 is small for i = 0 … n, hence perceived as similar, the dissimilarity between A0 and An can be large, hence perceived as different. In this way, we show how dissimilarity-enriched categories of qualia resolve the Sorites paradox. We claim that enriched categories accommodate various types of conscious experiences. An important extension of this claim is the application of the Yoneda lemma in enriched category; we can characterize a quale through a collection of relationships between the quale and the other qualia up to an (enriched) isomorphism.

scholarly journals Identification and Characterization of a Novel Competence Gene,comC, Required for DNA Binding and Uptake inAcinetobacter sp. Strain BD413

1998 ◽  
Vol 180 (6) ◽  
pp. 1592-1595 ◽  
Author(s):  
Caroline Link ◽  
Sandra Eickernjäger ◽  
Dirk Porstendörfer ◽  
Beate Averhoff
Keyword(s):  
Electron Microscopy ◽  
Dna Binding ◽  
Natural Transformation ◽  
Leader Sequence ◽  
Wild Type ◽  
Type Iv Pilus ◽  
Competence Gene ◽  
Type Iv ◽  
Identification And Characterization

ABSTRACT A gene (comC) essential for natural transformation was identified in Acinetobacter sp. strain BD413. ComC has a typical leader sequence and is similar to different type IV pilus assembly factors. A comC mutant (T308) is not able to bind or take up DNA but exhibits a piliation phenotype indistinguishable from the transformation wild type as revealed by electron microscopy.

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