Visual Echo Research Articles

Enhancing Arrhythmogenic Right Ventricular Cardiomyopathy Detection and Risk Stratification: Insights from Advanced Echocardiographic Techniques.

The echocardiographic diagnosis criteria for arrhythmogenic right ventricular cardiomyopathy (ARVC) are highly specific but sensitivity is low, especially in the early stages of the disease. The role of echocardiographic strain in ARVC has not been fully elucidated, although prior studies suggest that it can improve the detection of subtle functional abnormalities. The purposes of the study were to determine whether these advanced measures of right ventricular (RV) dysfunction on echocardiogram, including RV strain, increase diagnostic value for ARVC disease detection and to evaluate the association of echocardiographic parameters with arrhythmic outcomes. The study included 28 patients from the Heart Institute of São Paulo ARVC cohort with a definite diagnosis of ARVC established according to the 2010 Task Force Criteria. All patients were submitted to ECHO's advanced techniques including RV strain, and the parameters were compared to prior conventional visual ECHO and CMR. In total, 28 patients were enrolled in order to perform ECHO's advanced techniques. A total of 2/28 (7%) patients died due to a cardiovascular cause, 2/28 (7%) underwent heart transplantation, and 14/28 (50%) patients developed sustained ventricular arrhythmic events. Among ECHO's parameters, RV dilatation, measured by RVDd (p = 0.018) and RVOT PSAX (p = 0.044), was significantly associated with arrhythmic outcomes. RV free wall longitudinal strain < 14.35% in absolute value was associated with arrhythmic outcomes (p = 0.033). Our data suggest that ECHO's advanced techniques improve ARVC detection and that abnormal RV strain can be associated with arrhythmic risk stratification. Further studies are necessary to better demonstrate these findings and contribute to risk stratification in ARVC, in addition to other well-known risk markers.

Visual audience gatekeeping on social media platforms: A critical investigation on visual information diffusion before and during the Russo–Ukrainian War

AbstractGatekeepers, including prerogative elites and institutions, possess multifaceted tools for controlling information. Historically, these gatekeepers have systematically instrumentalized visual information to shape audience perceptions in alignment with specific agendas. However, the advent of social media platforms has disrupted these power dynamics, empowering audiences through user‐driven visual information exchanges. This has led to visual audience gatekeeping whereby users act as audience gatekeepers by selectively disseminating visual content, thus shaping information diffusion. While this democratisation of gatekeeping holds considerable promise for user empowerment, it also presents risks. These risks stem from the inherently persuasive yet manipulative qualities of visual content, compounded by users' susceptibility to unconscious biases, especially during polarising events. Therefore, we critically investigated visual audience gatekeeping in the context of the Russo–Ukrainian War, specifically focusing on a Reddit subforum devoted to Russia‐related discussions. We find that visual audience gatekeeping operates within a paradigm that reflects the social reality the audience embraces. Audience gatekeepers disseminate visual information both to reproduce and defend an idealised conception of this social reality. Collectively, they produce a visual echo chamber characterised by low information diversity, which, in turn, reinforces and perpetuates the incumbent paradigm. However, heightened social tensions can trigger a paradigm shift and amplify the reproduction and defence processes, increasing the potential for the diffusion of more radical and extreme visual narratives. Based on our findings, we propose a theoretical model of visual audience gatekeeping, which has important implications for research on visuals, gatekeeping and social media platforms.

Storying Strata: Entangling Coal and Energy Futures in Australia and India

ABSTRACT This article argues that the storying of fossiliferous geological strata opens up geopolitical possibilities for climate justice and ethical energy futures. Our more-than-human approach to the fossil-fuel industry and more specifically coal trade is sparked by ongoing political controversies and protests that have erupted over the development of the Galilee coal Basin in central Queensland, Australia by Indian mining conglomerates. Through a focus on this case study, we first draw attention to toxic border thinking on development, fossil fuel energy futures and climate change enabled by state-corporate collusions. Second, we argue for opening up decolonial horizons by dwelling in the border – the border that alerts us to the distributed agency of geologic life and vitality of fossilised seed ferns. Thinking with deep time and geological strata we explore the geopolitics of ‘clean coal’ and limitless groundwater that justifies mining in the Galilee basin and the establishment of new thermal plants on Adivasi lands in India. Attention to the materiality of fly ash and its transformation into cement for construction in India, Bangladesh, Nepal, and Bhutan highlights more sustainable energy use, but we argue that this carbonised cement would also linger as a future fossil from the Anthropocene that refuses extinction. Finally, by thinking with the artwork Towards a Glass Monument (2017–2019) by Tom Nicholson and Geoffrey Wallace we encounter a method for shifting viewer perspectives on coal from its identity as a homogeneous fuel source to a delicate historical record of past flora. The article demonstrates that even when worlds inhabited by racialised and marginalised peoples are silenced, the materiality of coal, ash, water and the visual echo of fossiliferous plant spores seed more-than-human framings of justice. We position both our case study exploration and Towards a Glass Monument as examples of how to story strata with the aim of opening up geopolitical possibilities for more-than-human climate justice.

On the Castelnuovo-Tedesco Version of Platero y yo

Music is feeling, then --Wallace stevens ROUGHLY fifty years ago there appeared two approaches to Platero y yo. On one hand, Michael P. Predmore published his thoroughgoing 1970 study of of Platero y yo, which Hispanic literary criticism has rightly regarded as foundational. Predmore defines structure as the underlying principle or principles which give shape to an expressive (56), which he identifies as the mysterious process of metamorphosis (64). On other, and only a decade earlier, Italian composer, Mario CastelnuovoTedesco, published his little-known Platero y yo, per voce recitante e chitarra, op. 190, 1960. My purpose in what follows is not to compare these two approaches to famous work but to see how well musician's world of Platero y yo reflects that depicted in poemario en prosa of Spanish poet. Can it be said to have done justice to Juan Ramon's masterpiece? At first glance prospect does not look promising: one hundred and thirty-eight pieces in Juan Ramon's poemario are drastically reduced in Castelnuovo-Tedesco's platero to a mere twenty-eight, divided into four books of seven items, as follows (titles and numbers at left are as printed in score, under C-T, original numbers are on right, under JRJ) (see p. 200). Platero y yo contains some fifty direct or indirect references to seasons, which include names of four seasons, of several months, and of seasonal religious festivals (Carnaval, Navidad, Reyes). Some of these form titles of specific poemas. These references do not always follow normal calendar sequence: one season often recalls or anticipates another. The use of internal flashback and flash-forward reminds us that, although of Platero y yo reflects seasonal cycle, temporal span of work is not confined to that one single year in which Platero may be seen to progress from birth in spring to death following winter. Juan Ramon has confessed that Platero is a composite of several donkeys who served as his companion during his life in Moguer. The year covered in work is thus a symbolic one of repeatedly changing seasons in which donkey and master each mature. (1) While only six of Juan Ramon's seasonal references occur in Castelnuovo-Tedesco's reduced cycle they represent all three categories of season, month, and festival, either in title or text. Both works begin in Platero's childhood and end on anniversary of his death and apparent resurrection. But while Platero y yo is structured on solar cycle of earth's four seasons, Castelnuovo-Tedesco's reduced version appears to be based on that of lunar month, each set of seven pieces corresponding to phases of moon. At same time each of these phases reflects beginning and end of complete solar cycle of original Spanish text. (2) If Castelnuovo-Tedesco's reduction of Juan Ramon's one hundred and thirty-eight prose poems into a new work of twenty-eight pieces divided into four groups of seven is indeed based on ordering principle of lunar month, composer would have found ample evidence in spanish text to support such a plan. There are fourteen settings of night sky in Platero y yo, eight clustered from poemas II-XIII, remaining six scattered from LIX to CXX. Castelnuovo-Tedesco uses five of these: II, III, X, XIII, and CXII. The word occurs in eleven poemas in Juan Ramon, eight between LII and LXXXIII. Castelnuovo-Tedesco uses five of these, including LII, LXXVIII, LXXXIII triad. The pivotal occurrence is La luna itself, brief but as full as an egg with imagery of circularity and transformation. In an almost casual visual echo of paradox of El pozo Platero drinks dos cubos de agua con estrellas (201), from barnyard well and lento y distraido (201) returns to his master lying in stable doorway. …

Dio da dio: La maschera di Cristo, Giove Serapide e il mosaico di Santa Pudenziana a Roma

The Christ Enthroned in Santa Pudenziana, understood as a visual echo of Imperial images or pagan gods, has always been considered in the context of the decoration of the entire apse mosaic. This study, in contrast, focuses specifically on the face and figure and their resemblance to images of Jupiter Serapis. In the environment of early fifth-century Rome, the similarity cannot be accidental. Archeological investigations have demonstrated that the Serapis image was present all over the city; at the same time, Christian authors viewed Serapis as an incarnation of the devil. This paradox is clarified by considering it in the period after the destruction of the Alexandria Serapeum in 391: a notion then circulating was that Serapis had foreseen his own death in the triumph of Christianity. An extreme interpretation is found in Jerome’s words: “Iam et Aegyptius Serapis factus est Christianus”. Christ would therefore have adopted the visage of his converted enemy. This reasoning leads to assigning an earlier d...

Cortical stimulation consolidates and reactivates visual experience: neural plasticity from magnetic entrainment of visual activity

Delivering transcranial magnetic stimulation (TMS) shortly after the end of a visual stimulus can cause a TMS-induced ‘replay' or ‘visual echo' of the visual percept. In the current study, we find an entrainment effect that after repeated elicitations of TMS-induced replay with the same visual stimulus, the replay can be induced by TMS alone, without the need for the physical visual stimulus. In Experiment 1, we used a subjective rating task to examine the phenomenal aspects of TMS-entrained replays. In Experiment 2, we used an objective masking paradigm to quantitatively validate the phenomenon and to examine the involvement of low-level mechanisms. Results showed that the TMS-entrained replay was not only phenomenally experienced (Exp.1), but also able to hamper letter identification (Exp.2). The findings have implications in several directions: (1) the visual cortical representation and iconic memory, (2) experience-based plasticity in the visual cortex, and (3) their relationship to visual awareness.

The End of the World in Medieval English Religious Drama

This paper focuses on treatments and prophesies of the last things in late medieval English religious drama. It looks at how the end of the York, Coventry, and Towneley Plays illustrate the multi-media revival of lay catechesis that followed the Council of Constance, while reaching back to the major works of fourteenth-century vernacular theology such of The Prick of Conscience, to express in new and imaginative ways the concatenation of the end of one life and the end of all, of general and particular judgement. The scene is set by reference to the York pageant of Doomsday in the context both of its wider material environment as found in contemporary local stained glass, wills and texts, and of civic patronage. The argument goes on to challenge the traditional divide between biblical cycles and morality plays to show how in a number of instances, plays depicting scriptural history were infiltrated by characters—Christ's torturers in the lost Passion Play from New Romney, the Worms of Conscience in the lost Judgement pageant from Coventry, and the devil Tutivillus in the Towneley Judicium—whose reference points lie as much in tropological allegory as in the narratives of the Bible and apocrypha, and draw on the liturgy of the Church and on sacramental theology to make explicit the old aphorism that Christ is recrucified daily. The paper ends with an exploration of the pageant of The Raising of Lazarus, eccentrically located following the Judicium in the Towneley manuscript. In it Lazarus, the moment he has risen, delivers a long speech on life beyond the grave that eclipses the preceding brief narrative of his death and resurrection, confronting the audience with a visual echo—or anticipation—of the dead rising up on the last day. The thrust of all civic dramatic presentations of the end of the world blend in various imaginative ways biblical and apocryphal narrative material with moral allegory, commentary on contemporary social abuses, and personal catechesis, as all the dramatists, following the pressure for renewal of the lay devotional agenda in the period of their production, provoke their audiences into a state of spiritual anxiety in which the apocalyptic vision is personal, participatory, and probably imminent.

ULTRASONOGRAPHIC (USG) IMAGING IN OROFACIAL DISEASES– A REVIEW

Diagnostic ultrasound has become a radiology subspecialty. Ultrasonography(USG) is a procedure in which highenergy sound waves are bounced off internal tissues or organs and make echoes, which are picked up by the transducer and converted into an electrical signal and then into a real-time black, white and grey visual echo picture, which is displayed on a computer screen. The principles, various indications, advantages, disadvantages and advanced applications of ultrasonography in relation to maxillofacial region are enlightened in this review article.

Falling Back into History: The Uncanny Trauma of Blackface Minstrelsy in Spike Lee's Bamboozled

Falling Back into HistoryThe Uncanny Trauma of Blackface Minstrelsy in Spike Lee's Bamboozled Gregory Laski (bio) …nobody, black or white, wants to revisit this stuff. I know there'll be a resistance to this film, like, "Why is Spike bringing this stuff back? That was the last century; we're in a new century, a new frontier." I think it's important that we look at this stuff. It has to be confronted. Blackface is part of American history. —Spike Lee, in a 2000 interview about Bamboozled He is obliged to repeat the repressed material as a contemporary experience instead of … remembering it as something belonging to the past. —Sigmund Freud, Beyond the Pleasure Principle To be traumatized is precisely to be possessed by an image or event. —Cathy Caruth, Trauma: Explorations in Memory Late in Spike Lee's Bamboozled, the uncanny figure of Abraham Lincoln in blackface steps forward onto the stage of Mantan: The New Millennium Minstrel Show, the wildly popular, all-black cast variety television program at the center of the 2000 film. Dressed in Lincoln's traditional hat and black suit, Honeycutt (Thomas Jefferson Byrd), The New Millennium Minstrel Show's African American emcee, declares: "Four score and seven years ago, they was kicking our black asses. Boy, I mean, they had a whip, and they was kicking our black asses from can't see in the morning until can't see at night. But this is the new millennium!" As he sustains the final syllable of his last phrase—"this is the new millennium"—Honeycutt strikes a haunting pose: he leans backward toward the stage's rear curtain, which displays the larger-than-life image of a minstrel character, whose distorted face, twisted nose, crimson lips, and gaping mouth threaten to engulf Honeycutt and overtake the screen. Approaching the audience assembled in the studio for the show as the segment continues, the emcee extends both of his arms horizontally, tilts his head back, and assumes a cross-like posture that invokes the specter of a nearly falling body, a visual echo of Honeycutt's descent into the stage backdrop we saw a few frames earlier. From the aerial view that the camera provides as it lingers on this tableau, it seems as if we witness Honeycutt, his movement suspended in time and space, in the moment before he will fall backward. [End Page 1093] Phantasmagorically raising Lincoln from the dead, this scene in Bamboozled signifies on the lines and likeness of the sixteenth president, deploying the form of entertainment he himself enjoyed. But here minstrelsy serves as a vehicle that reworks Lincoln's conventional image as the political figure who, so the official narrative goes, instituted black freedom and, instead, makes him suffer the nation's (still very much open) "wounds" of slavery, which in his Second Inaugural Address the president wanted so much to "bind up" (333).1 In its overlaying of touchstone chapters in the racial history of the United States—the Civil War, the Emancipation Proclamation, and, most significantly, the centuries of slavery that prepared the way for these events—Honeycutt's blackface Lincoln exposes the lie of racial progress in America, rewriting the traditional narrative of black liberation in which the epoch of slavery gives way to that of freedom, and testifying that to be black in the "new millennium" is still to be subject to physical and psychological abuse, to have one's "ass kicked" and psyche wounded by the "master," who, in the case of the film, assumes the guise of the white media establishment that coerces African American actors to perform in blackface in order to earn a living in the entertainment industry. Just as Honeycutt's figure continually threatens to fall in this scene, Bamboozled stages what this essay terms a fall back into history: a collapsing of the temporal boundaries between the nineteenth century and the new millennium, between the eras of slavery and freedom—in short, between past and present. That Lee's film resurrects the blackface caricatures of the putative "past" even as it presumably sets out to critique them has been the subject of significant controversy and debate.2 Yet critics...

Robust and Accurate Visual Echo Cancelation in a Full-duplex Projector-Camera System

In this paper we study the problem of "visual echo" in a full-duplex projector-camera system for telecollaboration applications. Visual echo is defined as the appearance of projected contents observed by the camera. It can potentially saturate the projected contents, similar to audio echo in telephone conversation. Our approach to visual echo cancellation includes an offline calibration procedure that records the geometric and photometric transfer between the projector and the camera in a look-up table. During run-time, projected contents in the captured video are identified using the calibration information and suppressed, therefore achieving the goal of cancelling visual echo. Our approach can accurately handle full-color images under arbitrary reflectance of display surfaces and photometric response of the projector or camera. It is robust to geometric registration errors and quantization effects and is therefore particularly effective for high-frequency contents such as texts and hand drawings. We demonstrate the effectiveness of our approach with a variety of real images in a full-duplex projector-camera system.

Collected Writings of Samson Occom, Mohegan: Leadership and Literature in Eighteenth-Century Native America , and: American Indian Nonfiction: An Anthology of Writings, 1760s–1930s (review)

Reviewed by: Collected Writings of Samson Occom, Mohegan: Leadership and Literature in Eighteenth-Century Native America, and: American Indian Nonfiction: An Anthology of Writings, 1760s–1930s Gordon M. Sayre (bio) Collected Writings of Samson Occom, Mohegan: Leadership and Literature in Eighteenth-Century Native America Edited by Joanna Brooks, with a Foreword by Robert WarriorNew York: Oxford University Press, 2006445 pp. American Indian Nonfiction: An Anthology of Writings, 1760s–1930s. Edited by Bernd C. PeyerNorman: University of Oklahoma Press, 2007401 pp. The covers of both these books feature The Reverend Samson Occom, a mezzotint copy of a portrait painted by Mason Chamberlin (1727-1787) during Occom's tour of Britain in 1765-1768. As was common in eighteenth-century portraiture, Occom is finely dressed and poses alongside emblematic objects. What appear to be arrows hang on the wall behind him, and even as his gaze is focused on the viewer, he points to a passage in an open book. Most assume it is a Bible, although a curator at Dartmouth College, which owns the portrait, told me the words are not legible. The long tabs of his neckcloth make a visual echo of the pages of the book, with shaded rectangular fields that resemble text. Occom's pose resembles the 1828 portrait of Sequoyah by Charles Bird King, in which he points at one of the 86 characters of the Cherokee syllabary he invented. To compare the two portraits is to consider the alternatives of Native Americans who embraced European textuality and those who insisted on retaining their Native language, or textualized it to better compete with colonial languages. A viewer of the Occom or Sequoyah portrait is presented with an individual who directs our attention to a text, as if to instruct us. To contemplate such portraits is to be drawn into a loop between the authority of the text and the influence of the personage, and to wonder which is primary, or whether one is derived from the other. Sequoyah is famous not for creating discourses but rather textuality itself. His syllabary was used in the [End Page 219] Cherokee Phoenix newspaper edited by Elias Boudinot, a bilingual textualist who is among the authors included in Peyer's anthology as well as the subject of Theresa Strouth Gaul's 2005 book To Marry an Indian: The Marriage of Harriett Gold and Elias Boudinot in Letters, 1823-1839. Occom has come to the attention of many Early Americanists because his brief autobiographical narrative was included in Peyer's earlier anthology The Elders Wrote (1982) and, along with his A Sermon, Preached at the Execution of Moses Paul, an Indian (1772) was selected for the Heath, the Norton, and other major anthologies of American literature. But this was the tip of an iceberg. Joanna Brooks now presents a "'big book' of Native North American writing from the colonial era" (39). With prodigious editorial work, she has transcribed and annotated more than four hundred dense pages of Occom's extant letters, journals, sermons and hymns, mostly from archives at Dartmouth College and the Connecticut Historical Society. The portraitists of Occom and Sequoyah created loops of reference yet remained outside them. One might think of the Collected Writings of Samson Occom, Mohegan, as a textual portrait, and of American Indian Nonfiction as a series of portraits. The books create for their audiences an image or series of images of learned persons, and create relationships between the personage[s] and texts. The act of creation is one not of a painter but of an editor. Like the portraits, Brooks's editorial apparatus and, to a lesser degree, Peyer's anthology suggest relationships between textual and nontextual sources, between alphabetic and non-alphabetic literacy, and between English, the language of the dominant colonizers, and the multiple native languages of North America. Brooks opens her introduction with an account of a "round wooden box fashioned from the bark of an elm tree and entwined with elaborately carved vines, leaves, and dotted lines [which] was catalogued among the holdings of the Peabody Essex Museum" (3). In 1995, when Mohegan tribal representatives visited the museum to "survey its holdings for possible repatriation," "tribal medicine woman Gladys Tantaquidgeon" explained...

Research on the acoustic features of stutterer’s voices for the purposes of computer animation

This paper deals with computerized visual echo, by means of which an animated image of lips speaking in chorus with the stutterer is provided. The computer animation is based on identifying the acoustic features of the Polish vowels. Only two parameters and identifying map could be made and with its help the area of each vowel occurrence could be determined. Then every area was assigned the characteristic image of lips that is typical of articulation of the vowel connected with this area. Three identifying maps are needed–for male voices, female voices, and children’s voices. They were elaborated on the basis of examination of 30 correct speaking people. Attempts were made at identifying vowels uttered by 12 stutterers on the basis of maps created earlier. For the stutterer’s voices the results of identification range around 70%. However, too small a group was examined to draw definite conclusions. Therefore, similar investigation will be continued, so as to finally confirm the applicability of computerized visual echo to stutterer’s therapy.

Influence of visual echo and visual reverberation on speech fluency in stutterers.

Influence of visual echo and visual reverberation on speech fluency in stutterers.

The interstellar light echoes around SN 1987A

The observed light echoes around SN 1987A are modeled by dust in planar clouds roughly 120 and 330 pc in front of the supernova. The expected echo profiles depend on the observed light curve and on the cloud thicknesses. The surface brightness and colors of the echoes are modeled using a mix of silicate and graphite grains appropriate to the Large Magellanic Cloud (LMC). The model colors approximately agree with the observed ones. The observed surface brightness suggests that the dust column density in the echo clouds is comparable to the total dust column density in the LMC toward SN 1987A. The model predicts the presence of a narrow ultraviolet echo outside the visual echo; it should be detectable with future ultraviolet observatories and will give information on the supernova near the phase of shock breakout.

The effect of attachment on radio echo observations of meteors

This paper is concerned with the effects of electron attachment to neutral air molecules on the characteristics of radio echoes from meteor trails. Previously it has been assumed that diffusion processes were primarily responsible for the reduction of volume electron density in a meteor trail, and also in limiting the echo duration. In a companion paper a value of the attachment coefficient β e = 5 x 10 -15 cm 3 s -1 has been determined from combined photo­graphic and radio echo observations of a meteor. An effect of an attachment coefficient of this magnitude is to reduce the expected echo duration by a factor of 1000 or more for a bright fireball. The observed relation between visual meteor magnitude and echo duration is explained by this mechanism, as are the departures from the wavelength squared variation of echo dura­tion predicted by diffusion theory. Attachment processes also account for the observation that the final heights of enduring meteor echoes all centre about 95 km, even though bright meteors may show a maximum in light intensity below 80 km.