Star Bodies Research Articles

A feather star is born: embryonic development and nervous system organization in the crinoid Antedon mediterranea.

Crinoids belong to the Echinodermata, marine invertebrates with a highly derived adult pentaradial body plan. As the sister group to all other extant echinoderms, crinoids occupy a key phylogenetic position to explore the evolutionary history of the whole phylum. However, their development remains understudied compared with that of other echinoderms. Therefore, the aim here was to establish the Mediterranean feather star (Antedon mediterranea) as an experimental system for developmental biology. We first set up a method for culturing embryos in vitro and defined a standardized staging system for this species. We then optimized protocols to characterize the morphological and molecular development of the main structures of the feather star body plan. Focusing on the nervous system, we showed that the larval apical organ includes serotonergic, GABAergic and glutamatergic neurons, which develop within a conserved anterior molecular signature. We described the composition of the early post-metamorphic nervous system and revealed that it has an anterior signature. These results further our knowledge on crinoid development and provide new techniques to investigate feather star embryogenesis. This will pave the way for the inclusion of crinoids in comparative studies addressing the origin of the echinoderm body plan and the evolutionary diversification of deuterostomes.

The Narrative Ploy of Double casting -Reincarnates of the Star Bodies in Hindi Films

This paper through a critical review of extant literature and analysis of prevalent discourse seeks to understand the narrative strategy of deploying stars in double casts or rules within a film. As a popular devise it has been recurrently deployed by successive generation of film makers from the early years of film making and to contemporary times. Apparently informed by the production logic of amplification of star value, this bricoleur ploy is embedded in mythical pantheon of plural incarnates of deities, in the anxiety and ambivalence of colonial and post- colonial experiences. It is unequivocally also an adaptation from Western literary paradigm and traditions.

Busemann--Petty-type problem for μ-intersection bodies

Abstract The Busemann–Petty problem of arbitrary measure for symmetric star bodies is proposed and studied by Zvavitch, which is a generalization of the classical Busemann–Petty problem. In this paper, we study the Busemann–Petty-type problem for homogeneous measure for general star bodies.

Dual Brunn-Minkowski inequality for $ C $-star bodies

<abstract><p>In this paper, we introduced the concept of $ C $-star bodies in a fixed pointed closed convex cone $ C $ and studied the dual mixed volume for $ C $-star bodies. For $ C $-star bodies, we established the corresponding dual Brunn-Minkowski inequality, dual Minkowski inequality, and dual Aleksandrov-Fenchel inequality. Moveover, we found that the dual Brunn-Minkowski inequality for $ C $-star bodies can strengthen the Brunn-Minkowski inequality for $ C $-coconvex sets.</p></abstract>

New mixed star bodies and related volume inequalities

New mixed star bodies and related volume inequalities

Convexity of the radial sum of a star body and a ball

AbstractWe investigate the convexity of the radial sum of two convex bodies containing the origin. Generally, the radial sum of two convex bodies containing the origin is not convex. We show that the radial sum of a star body (with respect to the origin) and any large centered ball is convex, which produces a pair of convex bodies containing the origin whose radial sum is convex.We also investigate the convexity of the intersection body of a convex body containing the origin. Generally, the intersection body of a convex body containing the origin is not convex. Busemann’s theorem states that the intersection body of any centered convex body is convex. We are interested in how to construct convex intersection bodies from convex bodies without any symmetry (especially, central symmetry). We show that the intersection body of the radial sum of a star body (with respect to the origin) and any large centered ball is convex, which produces a convex body with no symmetries whose intersection body is convex.

Intangibility and Selfhood: Westworld as Allegory for Adaptation in the Digital Age

Abstract Despite the digital becoming ever more ubiquitous, the physical matters more than ever. We see this in interviews with actors who voice animated characters, actors who voice computer generated imagery (CGI) characters, and actors who voice other non-human characters. Many things present a challenge to the ways in which we understand the physical—the structures of meaning in the world primarily, along with the specific filmic ways we understand star bodies. These combine to create barriers to ‘seeing’ the truth of a character we might think, but this is fixated on an approach that privileges a hierarchy of actors over character. Equally, it is one that privileges body over character. The recent series of Westworld begins to challenge this, thinking about the ways in which while the physical may be required, audiences are able to think beyond it. It functions as a way to consider the digital adaptation of the self, and the return to the needs of the physical to express character. Ultimately, this article argues that although we cannot escape the physical, the hierarchies and boundaries we have in place for understanding the truth of the self remain as unfixed as ever, despite the recourse to adapting through non-physical means.

Stability related to the Lp$L_p$ Busemann–Petty problem

AbstractThe Busemann–Petty problem for asks: does imply for origin‐symmetric convex bodies K and L? Here, is the volume of K and the operator is the intersection body of K. In this paper, we study the linear stability and separation results related to the Busemann–Petty problem. A typical result we obtained is: for small enough, if K is an intersection body and L is a star body such that for any , the following inequality: implies where is the Minkowski functional of , and C is a positive number depending only on p and n. Moreover, we also prove the linear stability and separation results for the negative answer of the Busemann–Petty problem.

High-throughput segmentation, data visualization, and analysis of sea star skeletal networks

The remarkably complex skeletal systems of the sea stars (Echinodermata, Asteroidea), consisting of hundreds to thousands of individual elements (ossicles), have intrigued investigators for more than 150 years. While the general features and structural diversity of isolated asteroid ossicles have been well documented in the literature, the task of mapping the spatial organization of these constituent skeletal elements in a whole-animal context represents an incredibly laborious process, and as such, has remained largely unexplored.To address this unmet need, particularly in the context of understanding structure–function relationships in these complex skeletal systems, we present an integrated approach that combines micro-computed tomography, automated ossicle segmentation, data visualization tools, and the production of additively manufactured tangible models to reveal biologically relevant structural data that can be rapidly analyzed in an intuitive manner.In the present study, we demonstrate this high-throughput workflow by segmenting and analyzing entire skeletal systems of the giant knobby star, Pisaster giganteus, at four different stages of growth. The in-depth analysis, presented herein, provides a fundamental understanding of the three-dimensional skeletal architecture of the sea star body wall, the process of skeletal maturation during growth, and the relationship between skeletal organization and morphological characteristics of individual ossicles.The widespread implementation of this approach for investigating other species, subspecies, and growth series has the potential to fundamentally improve our understanding of asteroid skeletal architecture and biodiversity in relation to mobility, feeding habits, and environmental specialization in this fascinating group of echinoderms.

Film and Caste Anxieties in Early Twentieth-Century India

Film was one of the new technological inventions of the ‘long nineteenth century’ that often instilled a fear of loss of the existing way of life and of disturbing existing social structures. In India, this manifested in a variety of ways, such as through the censorship of films by the government, but also by social codes which created major barriers for many to work in the film industry. In this article, I discuss film and its negotiations with caste in the twentieth century through close reading of the Indian Cinematograph Committee Report, film magazines, advertisements, audience responses and the speeches of nationalist leaders. I argue that rather than democratising desire by producing the universally desirable object of the star body, popular films in India produced desire that conformed to existing caste structures. The paper contributes to debates about early cinema and caste beyond the question of representation.

The Orlicz–Lorentz centroid inequality for star bodies*

The Orlicz–Lorentz centroid inequality for star bodies*

Maximal Perimeters of Polytope Sections and Origin-Symmetry

Let $$P\subset {\mathbb {R}}^n$$ $$(n\ge 3)$$ be a convex polytope containing the origin in its interior. Let $${\text {vol}}_{n-2}({{\text {relbd}}(P\cap \lbrace t\xi + \xi ^\perp \rbrace )})$$ denote the $$(n-2)$$ -dimensional volume of the relative boundary of $$P\cap \lbrace t\xi + \xi ^\perp \rbrace $$ for $$t\in {\mathbb {R}}$$ , $$\xi \in S^{n-1}$$ . We prove the following: if $$\begin{aligned} {\text {vol}}_{n-2}({{\text {relbd}}(P\cap \xi ^\perp )}) =\max _{t\in {\mathbb {R}}}\,{\text {vol}}_{n-2}({{\text {relbd}}(P\cap \lbrace t\xi + \xi ^\perp \rbrace )}) \end{aligned}$$ for all $$\xi \in S^{n-1}$$ , then P is origin-symmetric, i.e., $$P=-P$$ . Our result gives a partial affirmative answer to a conjecture by Makai et al. We also characterize the origin-symmetry of $$C^2$$ star bodies in terms of the dual quermassintegrals of their sections; this can be seen as a dual version of the conjecture of Makai et al.

On the sine polarity and the Lp-sine Blaschke-Santaló inequality

This paper is dedicated to study the sine version of polar bodies and establish the Lp-sine Blaschke-Santaló inequality for the Lp-sine centroid body.The Lp-sine centroid body ΛpK for a star body K⊂Rn is a convex body based on the Lp-sine transform, and its associated Blaschke-Santaló inequality provides an upper bound for the volume of Λp∘K, the polar body of ΛpK, in terms of the volume of K. Thus, this inequality can be viewed as the “sine cousin” of the Lp Blaschke-Santaló inequality established by Lutwak and Zhang. As p→∞, the limit of Λp∘K becomes the sine polar body K⋄ and hence the Lp-sine Blaschke-Santaló inequality reduces to the sine Blaschke-Santaló inequality for the sine polar body. The sine polarity naturally leads to a new class of convex bodies Cen, which consists of all origin-symmetric convex bodies generated by the intersection of origin-symmetric closed solid cylinders. Many notions in Cen are developed, including the cylindrical support function, the supporting cylinder, the cylindrical Gauss image, and the cylindrical hull. Based on these newly introduced notions, the equality conditions of the sine Blaschke-Santaló inequality are settled.

A Modified Three-Dimensional Negative-Poisson-Ratio Metal Metamaterial Lattice Structure.

Mechanical metamaterials are of interest to researchers because of their unique mechanical properties, including a negative Poisson structure. Here, we study a three-dimensional (3D) negative-Poisson-ratio (NPR) metal metamaterial lattice structure by adding a star structure to the traditional 3D concave structure, thus designing three different angles with a modified NPR structure and control structure. We further study the mechanical properties via finite element numerical simulations and show that the stability and stiffness of the modified structures are improved relative to the control structure; the stability decreases with increasing star body angle. The star angle has the best relative energy absorption effect at 70.9°. The experimental model is made by selective laser melting (SLM) technology (3D printing), and the compression experiment verification used an MTS universal compressor. The experimental results are consistent with the changing trend in finite element simulation.

‘Dubai’ as a Place of Memory in Malayalam Cinema

This paper is an exploration of cinematic memory as a resource for remembering large-scale Keralan migration to the Gulf since the late 1960s. The south Indian state of Kerala, which predominantly speaks Malayalam, is a major contributor to the migrant labour force in the Gulf region for the last five decades. However, until recently, the migrant figured in the public discourse of Kerala as an economic agent alone. There has been increasing instances of memorialising the Gulf in the Malayalam public sphere since the beginning of the 2000s which brings to light the subjective aspects of the Gulf migration. However, what is lost in these accounts is the simultaneity and interlinked nature of the two places. Cinema, on the other hand, offers resources to inscribe the mutuality of the two places in the collective memory of Kerala. Invoking Pierre Nora’s concept of places of memory, the paper looks at cinematic renditions of ‘Dubai’ as one such site of memory in the present when the image of Dubai and the profile of Keralan migrant has undergone a shift. Taking the example of one Malayalam film, Pathemari (Salim Ahamed, 2015), and tracing its cinematic genealogy, this paper analyses the ways in which ‘Dubai’ is remembered and how this remembrance inscribes the Gulf as part of the collective memory of Kerala. The paper identifies the persistence of filmed space, intertextuality, and the archivality of the star body as the modes in which cinematic memory achieves this collective memorialisation. The mutuality between Kerala and Dubai, offered by cinematic memory, allows it to be an act of affective citizenship on the part of the migrants, i.e. embodied and sensorial acts of claiming the universal right to have rights.

On the roots of polynomials with log-convex coefficients

AbstractIn this paper, we consider the family of nth degree polynomials whose coefficients form a log-convex sequence (up to binomial weights), and investigate their roots. We study, among others, the structure of the set of roots of such polynomials, showing that it is a closed convex cone in the upper half-plane, which covers its interior when n tends to infinity, and giving its precise description for every $n\in \mathbb {N}$ , $n\geq 2$ . Dual Steiner polynomials of star bodies are a particular case of them, and so we derive, as a consequence, further properties for their roots.

Miniaturization during a Silurian environmental crisis generated the modern brittle star body plan

Pivotal anatomical innovations often seem to appear by chance when viewed through the lens of the fossil record. As a consequence, specific driving forces behind the origination of major organismal clades generally remain speculative. Here, we present a rare exception to this axiom by constraining the appearance of a diverse animal group (the living Ophiuroidea) to a single speciation event rather than hypothetical ancestors. Fossils belonging to a new pair of temporally consecutive species of brittle stars (Ophiopetagno paicei gen. et sp. nov. and Muldaster haakei gen. et sp. nov.) from the Silurian (444–419 Mya) of Sweden reveal a process of miniaturization that temporally coincides with a global extinction and environmental perturbation known as the Mulde Event. The reduction in size from O. paicei to M. haakei forced a structural simplification of the ophiuroid skeleton through ontogenetic retention of juvenile traits, thereby generating the modern brittle star bauplan.

Orlicz affine isoperimetric inequalities for star bodies

The original goal of this paper is to extend the affine isoperimetric inequality and Steiner type inequality of Orlicz projection bodies (which originated to Lutwak, Yang, and Zhang [32]), from convex bodies to Lipschitz star bodies (whose radial functions are locally Lipschitz).In order to achieve it, we investigate the graph functions of the given Lipschitz star body K: Along almost all directions u, we can define the graph functions on an open dense subset of the orthogonal projection of K onto u⊥.

The functional form of the dual mixed volume

This paper is to generalize the dual mixed volume of star bodies to that of dual quasi-concave functions by extending the radial Minkowski linear combination of star bodies to that of dual quasi-concave functions. We attempt to build up some functional versions of notions and inequalities from the dual Brunn-Minkowski theory. In particular, both the dual mixed Brunn-Minkowski inequality of star bodies and the dual Aleksandrov Fenchel inequality of star bodies are generalized to that of dual quasi-concave functions.

Queering Bodies: “Becoming-unrecognisable” in Wong Kar-Wai’s Happy Together

Abstract This paper is interested in the cinematic apparatus’s potential to produce affect which defamiliarises the visible presence of star-bodies in Wong Kar-wai’s Happy Together (chunguang zhaxie, 1997), thus invoking non-normative and new modes of thinking about queer identification and representation. By close reading the mise-en-scène of the two Iguazu falls sequences, the on-screen star bodies of Tony Leung and Leslie Cheung are defamiliarized when they produce Gilles Deleuze’s affect and “become-unrecognisable” as on-screen subjects. Through this, the encounters with the Iguazu Falls allow us to queer heteronormative and linear narrative time that is associated with (a movement towards) futurity. This inability to pass judgement, I argue, is the ethics of sexual desire which Happy Together proffers when we understand the body that queers and becomes unrecognisable through productive affective assemblages. Instead, we move through the transsensorial potentials for the cinematic assemblage to rethink modes of queering normativity and to redefine bodies in terms of plurality and multiplicity. To that end, this paper presents a new way of thinking about how film stars, familiar tourist spots and even a classic text like Happy Together may be defamiliarized through productions of affects, new-sensations, to provide more ways of revisiting and regarding the film anew.