This article examines Artaud's 1920s cinema texts, arguing that like other theorists writing at the time, Artaud envisaged the medium of cinema as capable of forging new types of corporeal experience, both through the types of bodies that were portrayed onscreen, and their relationship to the body of the audience, conceived as collective force rather than an individual spectator. It pays particular attention to Artaud's theories of corporeal materiality, and argues that these are relevant to more recent approaches to embodiment (...) and identification in film studies. Whilst Artaud never successfully put his own cinematic theories into practice, these are discussed in relation to Carl Theodor Dreyer's The Passion of Joan of Arc ( La Passion de Jeanne d'Arc , 1928), a film which puts distinctions between bodies into question in an unprecedented manner. Finally, through an analysis of the various different critical interpretations of Dreyer's film, the article considers the difficulties inherent in the notion of a universally intelligible affective body, arguing that there is a distinction to be made between a fascist appropriation of collective affect, and a type of body that overcomes the boundaries between self and other. (shrink)

Stomata, the most influential components in gas exchange with the atmosphere, represent a revealing system for studying cell fate determination. Studies in Arabidopsis thaliana have demonstrated that many of the components, functioning in a signaling cascade, guide numerous cell fate transitions that occur during stomatal development. The signaling cascade is initiated at the cell surface through the activation of the membrane receptors TOO MANY MOUTHS (TMM) and/or ERECTA (ER) family members by the secretory peptide EPIDERMAL PATTERNING FACTOR1 (EPF1) and/or a (...) substrate processed proteolytically by the subtilase STOMATAL DENSITY AND DISTRIBUTION1 (SDD1) and transduced through cytoplasmic MAP kinases (YODA (YDA), MKK4/MKK5, and MPK3/MPK6) towards the nucleus. In the nucleus, these MAP kinases regulate the activity of the basic helix‐loop‐helix (bHLH) proteins SPEECHLESS (SPCH), MUTE, and FAMA, which act in concert with the bHLH‐Leu zipper protein SCREAM (SCRM) (and/or its closely related paralog, SCREAM2). This article reviews current insights into the role of this signaling cascade during stomatal development. (shrink)

Langerhans cells (LCs), residing in the epidermis, are able to induce potent immunogenic responses and also to mediate immune tolerance. We propose that tolerogenic and immunogenic responses of LCs are directed by signaling from the epidermis and involve counter‐acting gene circuits that are coupled to a core maturation gene module. We base our analysis on recent genetic and genomic findings facilitating the understanding of the molecular mechanisms controlling these divergent immune functions. Comparing gene regulatory network (GRN) analyses of (...) various types of dendritic cells (DCs) including LCs we integrate signaling‐dependent (TGFβ, EpCAM, β‐Catenin) and transcription factor (IRF4, IRF1, NFκB) regulated gene circuits that appear to orchestrate the distinctive LC functional states. Our model proposes, that while epidermal signaling in the steady‐state promotes LC tolerogenic function, the disruption of cell‐cell contacts coupled with inflammatory signaling induces LC immunogenic programing. The conceptual framework emphasizes the sensing of discrete epidermal and inflammatory cues by resident LCs in dictating their genomic programing and cell state dynamics. (shrink)

The article elaborates an exegetical study of the figure of “Hell” present in the work of the martinican psychiatrist Frantz Fanon. This trope is thought of as a core element of the narrative of Black Skin, White Masks that is linked to reflections on racist alienation, the epidermis, the gaze, and the zone of non-being. Exploring the different modulations of “Hell”, the article makes a displacement that seeks to argue how the infernal of Fanon’s story, more than a metaphor, (...) accounts for the “real-lived” of the colonial world. Consequently, the racialized body and its lived experience offer a reading about “Hell” in an anaphoric and existential key that strains the modern-hegemonic grammars about the identities. From this starting point, the work discusses the problem of temporality linked to the critical tenor that at various moments in Black Skin... assumes the infernal architecture of colonialism narrated by Fanon. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Dewey and the Aesthetic Unconsciousness: The Vital Depths of Experience by Bethany HenningFrank X. RyanDewey and the Aesthetic Unconsciousness: The Vital Depths of Experience Bethany Henning. Lexington Books, 2022.In this important and splendidly crafted book, Bethany Henning recovers a philosophy of aesthetic wisdom distinct from the narrow epistemological lens dominant today. Unlike the psychological atomism of European Empiricism, from its outset, American philosophy embraced nature's aesthetic splendor and (...) the continuity between our thought and our world. Jonathan Edwards held that relations among ideas reflect beauty in the structure of being. For Ralph Waldo Emerson, each of us is a "transparent eyeball" where the cultivation of nature's spontaneous beauty fortifies our moral and spiritual agency. At the apex of this tradition is John Dewey, for whom Henning touts "aesthetic experience as the highest mode of human experience" (55).Although the aesthetic is generally associated with the cognitive evaluation of art, of special significance for Dewey is its non-reflective or unconscious dimension. Henning's appropriation of "unconscious"—the cradle of Freud's infantile id—is intentionally provocative. American culture, reflected in academic thought, has largely resisted appeals to subterranean urges and drives. In so doing, however, we perpetuate a myth of rational and moral exceptionalism that masks our history of colonialism, oppression, and crass commercialism. In accepting the unconscious, European thought has taken strides to acknowledge and address such ills. Despite America's disdain for psychoanalysis, Henning wonders whether it "could have accepted a dynamic unconscious, were it presented with an alternative mythology" (10).Dewey's alternative, says Henning, arises from his underappreciated notion of qualitative immediacy. In Henning's interpretation of this, meaning is embodied as a "sense of fulfillment" among accumulated habits—a "coming to terms with the world around us" through an "aesthetic (directly felt) connection between ourselves and the world." As such, to appreciate meaning, we must affirm the tacit, unconscious depth of experience; that is, we must "welcome aesthetic experience back into our philosophical lives" (5).Embodied meaning signifies that "the sensuous, lived body" is "the primary reality" (69). In this reality, qualitative immediacy is a non-reflective, aesthetic unity punctuated by "impulsions" arising from an organism's needs. Such needs are satisfied in organism-environment interactions where, says Dewey, "the epidermis is only in the most superficial way an indication of where an organism ends and its environment begins" (LW 10:61). As "a site of adaptive adjustments," Henning continues, "the body is responsive to the [End Page 114] brink of coalescence at the point of contact with the world, in which things that are 'outside of it' belong to it" (71). As such, the body-mind relation is a problem of aesthetics, not epistemology. For Dewey, as for Merleau-Ponty, the body "is the organic and dynamic condition of my thought" (75). The body is not a thing, however, but a process "always organically involved in exchanges" (86).Following the feminist thought of Susan Bordo, Henning agrees that the ascendance of the body amounts to a kind of philosophical recovery. Seventeenth-century science eviscerated the organic "female" universe of the Middle Ages. But this loss of an integrated world evoked existential fright, which Descartes tried to calm by subjugating feminine vagaries of the body to a masculine cognitive certitude bent upon controlling the whole of nature. In America today, this neurosis perpetuates our cultural alienation from our bodies, our environments, and one another (81–84). With the re-emergence of the body, however, it is possible to acknowledge and address this trauma."Feeling," in Dewey's sense, is unconsciously affective: a constant rhythm of disequilibrium and equilibrium, of need and resolution noticed only when a problem rises to the point of requiring our conscious attention. This affective "charge," this rhythm of sensed need and the desire to overcome it, is Dewey's appropriation of Plato's Erōs. Thomas Alexander casts Dewey's Erōs broadly as humanity's aesthetic investment in our world—our collective effort "to transform a biophysical environment into a world filled with meaning" (Alexander 11). But Henning turns to the more familiar sense of Erōs attuned not to the world at... (shrink)

Given the assertion of a relation between two types, like: “Epidermis has part some Keratinocyte”, we define silent change as any kind of change of the instance-relata of the relation in question that does not change the truth-value of the respective type-level assertion. Such assertions are notoriously difficult to model in OWL 2. To address this problem, we distinguish different modes of type-level relatedness giving rise to this problem and describe a conservative extension to the BFO top-level ontology that (...) allows expressing these modes. (shrink)

In this paper, we explore digitally fabricated aesthetic enhancements and modifications of the body as well as digitally fabricated fauna habitats. We will address how we utilize speculative works through our bio inspired digitally fabricated designs via two of our most recent projects: {skin} D.E.E.P. and in silico et in situ. Through these two projects we explore cultural implications of the intersection of technology and biologically inspired art/design. Technology has provided an ever increasing amount of data which has facilitated the (...) way data can be used in aesthetic explorations. Technology can redefine the human experience by enhancing our senses, experiences, and forms of expression. In our work {skin} D.E.E.P., we explore these ideas via augmentation through wearables and biomimetic expressions on the skin through digitally fabricated prosthetics. {skin} D.E.E.P. employs temporary biomimetic skin patterns via wearable 3D printed exoskeletons. The first series of this work mimics the patterns and textures of animal skin via ephemeral impressions onto human skin. Taking inspiration from shedding snakeskin, we shed the outer layer by removing the 3D printed prosthesis. The epidermis retains the negative imprint of the prosthetic mimicking the look of serpent skin. The dermis reestablishes the smooth form of the human skin as it heals itself within the hour, erasing the ephemeral imprint, symbolically representing rebirth and renewal. Investigating the ephemeral aesthetic of textured patterns on human skin will not by any means provide a solution to an engineering problem, yet acts as a larger philosophical basis to conduct a discussion about the possibilities of blending bio inspired designs. The manifestation of data into physical form occurs via digital fabrication in our most recent series in silico et in situ: fauna habitats in the age of voxels, where we aim to create a new ecosystem for animals and to potentially augment their habitat. The habitats include pollinator waterers, spider habitats and turtle basking platforms. This project pushes forward with a new piece—the development of a 20-foot avian sculpture that will solely exist to support the habitat of the Chimney Swift species. The Chimney Swift is a near-threatened bird species in the US. in silico et in situ investigates the interplay of art, nature and technology by contextualizing sculptural works and placing these sculptures into nature. The project serves as a breeding ground for a larger dialogue about nature, culture, human intervention, design art and technology. Providing the artwork in the public sphere, barrier free in nature, fosters this discourse. (shrink)

The concept of positional information is applied to a large amount of data obtained previously in experiments on developing and regenerating amphibian limbs. Only the proximo-distal axis of the limb is considered. It is shown that the concept provides a simple, unitary hypothesis which satisfactorily accounts for the experimental data, and may moreover suggest meaningful new approaches. It is suggested that the boundaries of the bipolar limb system lie in the girdle skeleton and at the distal end of the limb, (...) respectively, and that it is the apical epidermis of the growing or regenerating limb which defines the distal boundary conditions. A relatively stable gradient of positional information is assumed to be set up in the mesoderm . It is further shown that the differentiated limb retains its positional information and upon amputation imparts it to the base of the blastema. To explain an apparent discrepancy between the developing and the regenerating limb, it is proposed that dedifferentiation of mesodermal limb tissues upon amputation entails a change of positional value in the mesenchyme. Consequently, the amputation level does not once and for all specify the positional value at the proximal end of a mass of blastemal mesenchyme, particularly when the mesenchyme is transplanted in such a way that its linear size decreases or increases. (shrink)

Experiential and behavioural aspects of emotions can be measured readily but developing a contactless measure of emotions’ physiological aspects has been a major challenge. We hypothesised that different emotion-evoking films can produce distinctive facial blood flow patterns that can serve as physiological signatures of discrete emotions. To test this hypothesis, we created a new Transdermal Optical Imaging system that uses a conventional video camera to capture facial blood flows in a contactless manner. Using this and deep machine learning, we analysed (...) videos of the faces of people as they viewed film clips that elicited joy, sadness, disgust, fear or a neutral state. We found that each of these elicited a distinct blood flow pattern in the facial epidermis, and that Transdermal Optical Imaging is an effective contactless and inexpensive tool to the reveal physiological correlates of discrete emotions. (shrink)

Since his beginnings, Man has produced art: gests and works in some way bound to the essence of man's existence, gests and works grafted onto the epidermis of the world, yet gests and works for transcending the immediate givens, for understanding veiled realities and future possibilities: gests and works of global apprehension, brought about and nourished through the ages by elementary needs, by visceral fears, by existential hopes.

Skin is one of the most thoroughly studied epithelia and can be used as a model for transcriptional control of epithelial differentiation. In particular, the stages of epidermal development and differentiation from a simple epithelium are well characterized. Temporal gene expression during development can be used to assign roles for transcription factors in epidermal differentiation. Approaches to understanding transcriptional regulation in epidermis include extensive promoter analysis and expression studies, in some cases coupled to functional studies. This work has not (...) produced any consensus about the importance of any particular factor or class of factors in epidermal specification. There is, as yet, nothing similar to the myo D family of tissue‐specific and cell‐type determining factors in epidermis. These studies, however, have revealed much about control of the differentiation process in epidermis. Most recently, there has been a suggestion that epithelial transcription can be influenced directly by the status of the adhesion complexes at the cell surface, providing a direct link between one of the distinguishing features of the epithelial state and gene transcription. (shrink)

Cellular pattern formations of some epithelia are believed to be governed by the direct lateral inhibition rule of cell differentiation. That is, initially equivalent cells are all competent to differentiate, but once a cell has differentiated, the cell inhibits its immediate neighbors from following this pathway. Such a differentiation repeats until all non-inhibited cells have differentiated. The cellular polygonal patterns can be characterized by the numbers of undifferentiated cells and differentiated ones. When the differentiated cells become large in size, the (...) polygonal pattern is deformed since more cells are needed to enclose the large cell. An actual example of such a cellular pattern was examined. The pupal wing epidermis of a butterfly Pieris rapae shows a transition of the equivalent-size cell pattern to the pattern involving large cells. The process of the transition was analyzed by using the method of weighted Voronoi tessellation that is useful for treatment of irregularly sized polygons. The analysis supported that the pattern transition of the early stage of the pupal wing epidermis is governed by the lateral inhibition rule. The differentiation takes place in order of largeness, but not smallness, of the apical polygonal area in the differentiating region of the pupal wing. (shrink)

The change in shape of the C. elegans embryo from an ovoid ball of cells into a worm-shaped larva is driven by three events within the cells of the hypodermis (epidermis): (1) intercalation of two rows of dorsal cells, (2) enclosure of the ventral surface by hypodermis, and (3) elongation of the embryo. While the behavior of the hypodermal cells involved in each of these processes differs dramatically, it is clear that F-actin and microtubules have essential functions in each (...) of these processes, whereas contraction of actomyosin structures appears to be involved specifically in elongation. Molecular analysis of these processes is revealing components specific to C. elegans as well as components found in other systems. Since C. elegans hypodermal cells demonstrate dramatically different behaviors during intercalation, enclosure and elongation, the study of cytoskeletal dynamics in these processes may reveal both unique and conserved activities during distinct epithelial morphogenetic movements. BioEssays 23:12–23, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

“Racism” is the name given to a type of behavior which consists in the display of contempt or aggressiveness toward other people on account of physical differences between them and oneself. It should be noted that this definition does not contain the word “race,” and this observation leads us to the first surprise in this area which contains many: whereas racism is a well-attested social phenomenon, “race” itself does not exist! Or, to put it more clearly: there are a great (...) number of physical differences among human groups, but these differences cannot be superimposed; we obtain completely divergent subdivisions of the human species according to whether we base our description of the “races” on an analysis of their epidermis or their blood types, their genetic heritages or their bone structures. For contemporary biology, the concept of “race” is therefore useless. This fact has no influence, however, on racist behavior: to justify their contempt or aggressiveness, racists invoke not scientific analyses but the most superficial and striking of physical characteristics —namely, differences in skin color, pilosity, and body structure.Thus, it is with good cause that the word “race” was placed in quotes in the title of this issue: “races” do not exist. I am less sure, however, that all the contributors managed to avoid postulating the existence, behind this word as behind most words, of a thing. In his introduction Gates remarks that “race, in these usages, pretends to be an objective term of classification, when in fact it is a dangerous trope,” and he goes on to describe as follows the goal of the special issue: “to deconstruct, if you will, the ideas of difference inscribed in the trope of race, to explicate discourse itself in order to reveal the hidden relations of power and knowledge inherent in popular and academic usages of ‘race’ ” . Up to a point, I agree with him, even if I cannot help pointing out the insistent allusions to certain contemporary critical theories —allusions which furnish proof that the author of these lines possesses a particular knowledge and thereby sets up a particular power relationship between himself and the reader. This, however, is not the problem. The problem arises on page 15, when the same author declares, “We must, I believe, analyze the ways in which writing relates to race, how attitudes toward racial differences generate and structure literary texts by us and about us.” What bothers me about this sentence is not so much that “generate” and “structure” allude to yet another critical theory as that its author seems to be reinstating what he himself referred to as the “dangerous trope” of “race”: if “racial differences” do not exist, how can they possibly influence literary texts? Tzvetan Todorov works at the Centre National de la Recherche Scientifique in Paris. His most recent book in translation is The Conquest of America . Criticism of Criticism is forthcoming. Loulou Mack is a free-lance writer and translator living in Paris. (shrink)

The Drosophila position‐specific (PS) integrins are members of the integrin family of cell surface receptors and are thought to be receptors for extracellular matrix components. Each PS integrin consists of an α subunit, αPS1 or αPS2, and a βPS subunit. Mutations in the βPS subunit and the αPS2 subunit have been characterised and reveal that the PS integrins have an essential role in the adhesion of different cell layers to each other. The PS integrins are especially required for the function (...) of the cell‐matrix‐cell junctions, where the muscles attach to the epidermis and where one surface of the developing wing adheres to the other. These junctions are similar to vertebrate focal adhesions and hemidesmosomes, which also contain integrins. Integrin‐mediated cell to cell adhesion via the extracellular matrix provides a way for tissues to adhere to each other without intermingling of their cells. (shrink)

Determination of cell fate in the developing eye of Drosophila depends on a precise sequence of cellular interactions which generate the stereotypic array of ommatidia. In the eye imaginal disc, an initially unpatterned epithelial sheath of cells, the first step in this process may be the specification of R8 photoreceptor cells at regular intervals. Genes such as Notch and scabrous, known to be involved in bristle development, alos participate in this process, suggesting that the specification of ommatidial founder cells and (...) the formation of sensory organs in the adult epidermis may involve a similar mechanism, that of lateral inhibition. The subsequent steps of ommatidial assembly, following R8 assignment, involve a different mechanism: Undetermined cells read their position based on the contacts they make with neighbors that have already begun to differentiate. The development of the R7 photoreceptor cell, one of the eight photoreceptor cells in the ommatidium, is best understood. An important role seems to be played by sevenless, a receptor tyrosine kinase on the surface of the R7 precursor. It transmits the positional information– most likely encoded by the boss protein on the neighboring R8 cell membrane – into the cell via its tyrosine kinase, which activates a signal transduction cascade. Constitutive activation of the sevenless kinase by overexpression of an N‐terminally truncated form results in the diversion of other ommatidial cells into the R7 pathway suggesting that activation of the sevenless signalling pathway is sufficient to specify R7 development. Genetic dissection of this pathway should therefore identify components of a signalling cascade activated by a tyrosine kinase. (shrink)

The post‐embryonic architecture of higher plants is derived from the activity of two meristems that are formed in the embryo: the shoot meristem and the root meristem. The epidermis of the shoot is derived from the outermost layer of cells covering the shoot meristem through repeated anticlinal divisions. By contrast, the epidermis of the root is derived from an internal ring of cells, located at the centre of the root meristem, by a precise series of both periclinal and (...) anticlinal divisions. Each epidermis has an independent origin. In Arabidopsis the mature shoot epidermis is composed of a small number of cell types: hair cells (trichomes), stomatal guard cells and other epidermal cells. In shoots, hairs take the form of branched trichomes that are surrounded at their base by a ring of accessory cells in a sheet of epidermal cells. The root epidermis is composed of two cell types: trichoblasts that form root hair cells and atrichoblasts that form non‐hair cells. Mutations affecting both the patterning and the morphogenesis of cells in both shoot and root epidermis have recently been described. Most of these mutations affect development in a single epidermis, but at least one, ttg, is involved in development in both epidermal systems. (shrink)

It has recently been shown that stem and progenitor cells undergo population self‐renewal to maintain epithelial homeostasis. The fate of individual cells is stochastic but the production of proliferating and differentiating cells is balanced across the population. This new paradigm, originating in mouse epidermis and since extended to mouse oesophagus and mouse and Drosophila intestine, is in contrast to the long held model of epithelial maintenance by exclusively asymmetric division of stem cells. Recent lineage tracing studies have now shown (...) that wound responses vary between tissues, and that a stem cell reserve is not essential as cycling progenitors and even differentiating cells contribute to regeneration. (shrink)

El problema del acceso al conocimiento suele inscribirse en los estrechos márgenes de lo metodológico. Sin embargo, dicha cuestión excede los límites de la pura practicidad y eficiencia. La posibilidad de saber exige una indagación que trascienda la pura epidermis del supuesto de un cúmulo de conocimientos dados y al alcance de todos. Dicha posibilidad es mucho más que la distancia que media entre el sujeto dispuesto a conocer y los contenidos a asimilar. El acceso al saber implica, además, (...) una mirada a la realidad sin la cual el contenido asimilable se desnaturaliza como nutriente espiritual. Por consiguiente, resulta pertinente indagar qué miradas de la realidad son las que sirven de sustento a la diversidad de los concretos accesos a los múltiples saberes. Tal es el núcleo vertebrador que recorre esta obra. Fundamentos, contextos y metodologías de la educación resulta así un subtítulo que pretende especificar el objeto de estudio de El acceso al conocimiento. Se trata tanto de una exposición objetiva como de una dilucidación comprometida, dirigidas ambas al corazón de los procesos formativos vigentes. Cada uno de los veintidós capítulos que componen El acceso al conocimiento ha sido expuesto por separado y públicamente en el seno de diversos Congresos Internacionales. Por tanto, cada uno de ellos ha sido sometido a debate en sesiones congresuales que abarcan seis años: desde el 2000 hasta el 2006. La compilación que aquí se presenta –y en la que se han mantenido las diversas modalidades de cita bibliográfica- tiene, pues, el valor añadido de intentar propiciar nuevos diálogos y renovadas reflexiones. (shrink)

I review how both the parasegmental and segmental frames are used in constructing the body plan of the arthropods. The parasegment is the primary genetic unit, as shown by Hox gene expression, and the parasegmental design is maintained in the nerve cord. It is, however, not maintained in the epidermis, where the cuticle grooves are segmental, and in the musculature, which is segmental in organisation. This frame shift is reflected in the sensory and motor nerve connections between the ganglia (...) and the periphery. I suggest that the need for movement in an organism equipped with a hard exoskeleton was the functional constraint that shaped this apparently complex mode of development. BioEssays 26:1117–1125, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

Dorsal closure (DC), the closure of a hole in the dorsal epidermis of Drosophila embryos by the joining of opposing epithelial cell sheets, has been used as a model process to study the molecular and cellular mechanisms underlying epithelial spreading and wound healing. Recent studies have provided novel insights into how different tissues function cooperatively in this process. Specifically, they demonstrate a critical function of the epidermis surrounding the hole in modulating the behavior of the amnioserosa cells inside. (...) These findings shed light not only on the mechanisms by which the behavior of different tissues is coordinated during DC, but also on the general mechanisms by which tissues interact to trigger global morphogenesis, an essential but yet poorly explored aspect of embryogenesis. (shrink)

The 5000 bristles that protrude from the cuticle of a Drosophila adult function as either mechanosensors or chemosensors, and they are arranged in surprisingly intricate patterns. Development of the patterns appears to involve five stages: (1) establishment of a coordinate system of ‘positional information’; (2) partitioning of the epidermis into areas where bristles either can or cannot originate; (3) selection of one or more bristle mother cells within each permissible area; (4) suppression of bristle development in the neighborhood of (...) each mother cell; and (5) differentiation of the mother cell to produce four or more descendant cells, each of which forms part of the bristle apparatus. Some of the genes that control these events participate in more than one stage, and others play key roles in roles in seemingly unrelated developmental pathways, including embryonic neurogenesis, body segmentation, and sex determination. (shrink)

New molecular markers for epidermal stem cells have enabled their isolation both in vitro and from the epidermis lying between hair follicles. Micro‐dissection experiments have localised a second population of stem cells within hair follicles. Epidermal stem cells have a patterned distribution in vivo. The patterning can be reconstituted in vitro, showing that it is generated by interactions between keratinocytes and that the differentiation of epidermal stem cells is regulated by signals from other keratinocytes. Recent evidence from transgenic mice (...) suggests that stem cell behaviour in the gut may be regulated by similar cell‐cell interactions in vivo. Candidate genes for mediating these interactions are the homologues of Drosophila cell fate patterning genes such as Notch and Wingless and the Cadherin family of cell‐cell adhesion molecules. The roles of stem cells and of mutations of the Patched gene in epithelial carcinogenesis are discussed. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Pax Americana and the World of Music EducationEstelle R. Jorgensen (bio)It may seem ironic to speak of a Pax Americana at a time when the United States is prosecuting a war and its aftermath.1 Still, imperialism, or the desire to keep the peace on one's own terms, has led other nations into war when their will and power was frustrated and thwarted. My purpose in this essay is to (...) raise four important and interrelated questions: What are the political tasks that hopeful music teachers, administrators, and those interested in their work need to undertake to pursue an ethically universalistic, democratic, and humane education? What are some guiding principleswhereby music educators and policy-makers can navigate this territory? What are the conditions that would facilitate educational dialogue of the sort that is needed? How should music to be taught in order to achieve the intellectual objectives necessary in dialogical education? I view these questions from the limited musical perspective of the Western classical tradition — a misnomer since it is now an international tradition practiced around the world by people of many different languages, ethnicities, and cultures — and in the context of my position that this tradition merits transformation.2 This is a particularly interesting example since its roots originally are European, Eastern, and African, and it potentially subverts the predominant American popular musical culture of our time.Michael Hardt and Antonio Negri write of a global empire in the making and the seeds of its decline and fall, the multitudes that arise against it and the challenges they encounter in making their voices heard in the political arena.3 The forces of globalization, interwoven as they are with those of capitalism and the ideologies that foster it, are so pervasive that it is difficult for nation states to resist. The powers of nation-states decline while pervasive internationalism lies like an "epidermis" over the many nation-states, religions, languages, and ways of life that characterize societies on planet earth.4 The United States might champion capitalism and its own [End Page 1] breed of democratic ideology, yet globalization engulfs it such that it becomes the creature of its own making. Its values and culture might lie at the heart of the cultural, economic, and political agents of globalization — the multinational corporations with their corresponding distribution networks, interlocking international corporate directorships, licensing agreements, technological inventions, and powerful political and religious liaisons — yet even the United States becomes the child of forces it has exported throughout the world and that it is now unable to control. A culture of fear and violence pervades the country.5 Outsourcing, off-shore export of production capacity, the power of the profit motive, and management decisions made far from the particular places they impact leave many Americans without jobs and security, and a sense of powerlessness to change their circumstances — a phenomenon that also appears in other countries. Eventually, as Hardt and Negri posit in Marxian vein, the people impacted by these developments both here and abroad begin to organize themselves and rise against the oppression they may at first sense if not fully understand; in the beginning they may march peacefully but as their anger and frustration grow, they may eventually revolt. One need not buy into their particular reading of history to notice that, at least over the long term of decades or centuries, there seem to be limits on the human willingness to tolerate oppression; when their patience is eventually exhausted, people resist, subvert, escape, or overthrow their oppressors.One of the particular challenges of our time is the "polyvocality" of contemporary societies. Globalism may constitute the epidermis overlying these "multiplicities and pluralities" but underneath are the hosts of differing tribes, religions, languages, colors, and identities. Ways need to be found for people to dwell together in peace and debate and reconcile their differences without resorting to violence.6 In such a world, even in societies that espouse democratic ideals and principles, moral conflicts cannot be avoided, and differences between and among individuals and groups are often deeply rooted, persistent, and pervasive. This necessitates forging mechanisms that enable deliberation about how to solve the conflicts that necessarily arise.7 Seyla... (shrink)

Terminally differentiating stratified squamous epithelial cells assemble a specialized protective barrier structure on their periphery termed the cornified cell envelope (CE). It is composed of numerous structural proteins that become cross‐linked by several transglutaminase enzymes into an insoluble macromolecular assembly. Several proteins are involved in the initial stages of CE assembly, but only certain proteins from a choice of more than 20 different proteins are used in the final stages of CE reinforcement, apparently to meet tissue‐specific requirements. In addition, a (...) variable selection of proteins may be upregulated in response to genetic defects of one of the CE proteins or tissue injury, in an effort to maintain an effective barrier. Additionally, in the epidermis and hair fiber cuticle, a layer of lipids is covalently attached to the proteins, which provides essential water barrier properties. Here we describe our current understanding of CE structure, a possible mechanism of its assembly, and various disorders that cause a defective barrier. BioEssays 24:789–800, 2002. Published 2002 Wiley Periodicals, Inc. (shrink)

Immunity against SARS‐CoV‐2 that is acquired by convalescent COVID‐19 patients is examined in reference to (A) the Th17 cell generation system in psoriatic epidermis and (B) a recently discovered phenomenon in which Th17 cells are converted into tissue‐resident memory T (TRM) cells with Th1 phenotype. Neutrophils that are attracted to the site of infection secrete IL‐17A, which stimulates lung epithelial cells to express CCL20. Natural Th17 (nTh17) cells are recruited to the infection site by CCL20 and expand in the (...) presence of IL‐23. These nTh17 cells are converted to TRM cells upon encounter with SARS‐CoV‐2 and continue to exist as ex‐Th17 cells, which exert Th1‐like immunity during a memory response. G‐CSF can induce nTh17 cell accumulation at the infection site because it promotes neutrophil egress from the bone marrow. Hence, G‐CSF may be effective against COVID‐19. Administration of G‐CSF to patients infected with SARS‐CoV‐2 is worth a clinical trial. (shrink)

Some aspects of insect development were reconsidered in relation toWolpert's concept of “positional information”, which was briefly summarized. His distinction between positional information and “polarity potential” was shown to be unnecessary. The question was discussed whether transdetermination inDrosophila imaginai discs is a re-specification or a re-interpretation of positional information. In the first case transdetermination would depend on spatial relationships in the blastema, whereas in the second case it would not. As to the so-called “prepattern mutants”, it was emphasized that in (...) all cases published so far the supposed prepattern alterations are accompanied by growth disturbances which may account for changes in the specification of positional information. “Regulation” in imaginai discs is of a particular kind in that it depends on a proliferation phase. It takes place according to rules which were newly formulated in terms of positional information; the salient point of these rules is a tendency to maintain the slope of the positional information “gradients” and to produce symmetrically reduplicated, often defective organs. A short description of the postulated determinative processes occurring in imaginai discs from the early embryo up to the pupal stage was given. Intermingling of cells from various discs has shown that the cells may restore the original patterns in so far as their positional information has been stably specified,i.e. up to the level of the organ districts; within the districts mosaics are formed, which shows that positional information is specified with respect to new reference points. Transplantation experiments involving the abdominal epidermis of some other insects point to the possibility of limited local shifts in the positional information, and of both increase and reduction of the slope of the positional information curve. (shrink)

Human skin produces numerous neurohormones and neuropeptides. Recent evidence has shown that the neuroendocrine regulation of human skin biology also extends to keratins, the major structural components of epithelial cells. For example, thyrotropin‐releasing hormone, thyrotropin, opioids, prolactin, and cannabinoid receptor 1‐ligands profoundly modulate human keratin gene and protein expression in human epidermis and/or hair follicle epithelium in situ. Since selected keratins are now understood to exert important regulatory functions beyond mechanical stability, we argue that neuroendocrine pathways of keratin regulation (...) are important for maintaining skin and hair follicle homeostasis. This invites innovative neuroendocrine therapeutic interventions for skin disorders characterized by abnormal keratin expression, ranging from psoriasis to genodermatoses, and for promoting skin wound healing and hair growth. This strategy can be probed in simple, but instructive and readily available human skin and hair follicle organ culture assays as ideal models for exploring this new neuroendocrine frontier in translational epithelial biology. (shrink)

A tissue is a geometrical, space-filling, random cellular network; it remains in this steady state while individual cells divide. Cell division is a local, elementary topological transformation which establishes statistical equilibrium of the structure. We describe the physical conditions to maintain stationary the epidermis (of mammals or of the cucumber), in spite of the fact that cells constantly divide and die. Specifically, we study the statistical equilibrium of the basal layer, a corrugated surface filled with cells, constituting a two-dimensional (...) topological froth. Cells divide and detach from the basal layer, and these two topological transformations are responsible for the stationary state of the epidermis. The topological froth is capable of responding rapidly and locally to external constraints, and is a good illustration of the plasticity of random cellular networks.Statistical equilibrium is controlled by entropy, both as a measure of disorder and as information, and is characterized by observable relations between average cell shapes and sizes. The technique can be applied to any random cellular network in dynamical equilibrium. Mitosis as the dominating topological transformation and the fact that the distribution of cell shapes is very narrow are the only inputs specific to biology. (shrink)

Because of its elegant simplicity, the Arabidopsis root has become a model for studying plant organogenesis. In this review we focus on recent results indicating the importance of signaling in root development. A role for positional information in root cell specification has been demonstrated by ablation analyses. Through mutational analysis, genes have been identified that play a role in radial pattern formation. The embryonic phenotypes of these mutants raised the possibility that division patterns in post‐embryonic roots are dependent on signaling (...) that originates during embryonic development. Analysis of expression of the SCARECROW gene indicates that it may play a role in this ‘top‐down’ signaling process. Characterization of root epidermis development has led to the identification of negative regulators of root‐hair formation. These appear to set up a prepattern which is reinforced by signaling by plant hormones. (shrink)

Long non‐coding RNAs (lncRNAs) have recently gained increasing attention because of their crucial roles in gene regulatory processes. Functional studies using mammalian skin as a model system have revealed their role in controlling normal tissue homeostasis as well as the transition to a diseased state. Here, we describe how lncRNAs regulate differentiation to preserve an undifferentiated epidermal progenitor compartment, and to maintain a functional skin permeability barrier. Furthermore, we will reflect on recent work analyzing the impact of lncRNAs on the (...) progression from normal epithelium to the development of skin disorders and cancer. (shrink)