Alice Serra

Atomic-scale computer simulation has been used to study the thermally activated atomic transport of self-interstitial atoms in the form of planar clusters in pure Cu and f -Fe. There is strong evidence that such clusters are commonly formed in metals during irradiation with high-energy particles and play an important role in accumulation and spatial distribution of surviving defects. An extensive study of the mobility of SIA clusters containing two to 331 interstitials has been carried out using the molecular dynamics simulation technique for the temperature range from 180 to 1200 K. The results obtained show that clusters larger than three to four SIAs are one-dimensionally mobile in both Cu and Fe. Large clusters of more than 100 SIAs in Cu and 300 SIAs in Fe have significantly reduced mobility. The problem of describing one-dimensional motion in three-dimensional space is discussed. An attempt is made to describe the mobility of SIA clusters within the approximation of 1D diffusion. For clusters in both metals the effective migration energy of 1D diffusion as estimated via the jump frequency of the cluster centre of mass is found to be independent of the number of SIAs in the clusters, although the cluster jump frequency decreases with increasing cluster size. Mechanisms of 1D mobility of interstitial clusters are discussed

Dieser Text geht von der Frage nach der Wahrheit, die durch die Rekonstruktion der Auseinandersetzung zwischen drei Vertreter des zeitgenössischen philosophischen Denkens dargelegt wird, nämlich: Edmund Husserl, Jean-Luc Marion und Jacques Derrida. Wenn bei Husserl das Problem der Wahrheit mit der Analyse der verschiedenen Modalitäten der Anschauung zusammengehört, in denen sich das Phänomen bewusst eintritt, wiederum mag Marion de Darstellungsweise des Phänomens mit dem Begriff „Gegebenheit“ umfassen: somit schließt diese nicht nur die Modalitäten der Anschauung ein, sondern auch die Intentionalität selbst, die sich irgendein etwas wendet. Nun weißt Derrida durch die Dekonstruktion der phänomenologischen Begriffe Anschauung und Gegebenheit darauf hin, dass die phänomenologische Betrachtung nicht ausreicht, um Zusammenhänge und Umstände nachzudenken, in denen sich die Wahrheit ohne anschaulichen Zug, ohne subjektive Intentionalität und in Widerstand gegenüber ihrer eigenen Sichtbarkeit anzeigt. Solche Nuancen hebt Derrida hervor, indem er die Gegebenheit und die „Gabe“ kontrastiert, und schließlich, indem er der Wahrheit den Charakter des Zeugnisses zuschreibt.

Linear elasticity theory and atomistic computer modelling were applied to study properties such as the formation energy, stress and displacement field for planar clusters of point defects and small dislocation loops. Two different interatomic potentials have been used to simulate perfect vacancy and interstitial clusters up to 6 nm in diameter in a {111} plane in a model of bcc Fe. The accuracy of the continuum description of formation energy, stress and displacement field depends on the cluster or loop size and the distance from its edge; it is better for large loops at large distance. However, even for the largest defect studied, the stress distribution, especially that inside the glide prism, calculated from the atomistic model is significantly wider than that estimated by elasticity theory. The difference between planar clusters of point defects and dislocation loops and the limitations of the linear elasticity description are discussed. It is concluded that clusters of up to about 2 nm in diameter cannot be described as dislocation loops in the isotropic continuum approach

RESUMO Este texto discute alguns problemas metodológicos e históricos concernentes à fenomenologia da consciência de imagem elaborada por Edmund Husserl e algumas de suas repercussões teóricas. Primeiramente será tematizado o escopo mais amplo em que a abordagem filosófica das imagens auferiu relevância no século XX, a saber, a assim chamada “virada icônica” ou “pictórica”, conforme as respectivas formulações de Gottfried Boehm e William Mitchell. Será situada nesse contexto a fenomenologia da imagem e, mais especificamente, a fenomenologia da consciência de imagem elaborada por Husserl, considerando-se, em especial, os eixos norteadores dos três direcionamentos que sobressaem nas teorias contemporâneas da imagem, a saber: as abordagens antropológica, semiótica e perceptiva. A partir da retomada de nuances semióticas remanescentes na fenomenologia da consciência de imagem, serão apresentados alguns pontos críticos acerca da classificação das análises de Husserl no escopo do direcionamento perceptivo e, finalmente, apontadas implicações do copertencimento à apresentação intuitiva da imagem daquilo que se denominará “circunstancialidade indicativa”. ABSTRACT This text addresses some methodological and historical problems concerning the phenomenology of image consciousness elaborated by Edmund Husserl as well as some of its theoretical repercussions. At first, I examine the broader scope in which the philosophical approach to images became relevant in the 20th century, the so-called “iconic turn” or “pictorial turn”, according to the respective terms proposed by Gottfried Boehm and William Mitchell. In this context I situate the phenomenology of image and, more specifically, the phenomenology of image consciousness elaborated by Husserl, considering, in particular, the guiding axes of three directions that stand out in contemporary theories of image, namely: the anthropological, the semiotic and the perceptual approach. By the resumption of semiotic nuances remaining in the phenomenology of image consciousness I present some critical points about the classification of Husserl’s analyses in the scope of perceptual approach. Finally, I point out some implications of the co-belonging to the intuitive image presentation of what can be called “indicative circumstantiality”.

In Critics of pure reason the notion of affection appears at first in the "Transcendental Aesthetic" and is unfolded on the notion of self-affection in the "Transcendental Analytic". Husserl, in manuscripts written from 1918, presents some developments of these Kantian notions. If by affection Kant explains that something can be given to the subject from the sensibility, that is, something that affects oneself from the external and the internal sense, however, Husserl extends the analysis of affection toward a broad spectrum of underlying phenomena, such as volitive acts, imaginative acts, drives and affects. Husserl also analyzes from a phenomenological point of view the Kantian implicit condition that, if anything is given to the subject in the internal consciousness of time, the relationship to itself must be thought as a temporal process. I intend to show that Husserl’s analysis of affection and its modulations unveil possible theoretical directions departing from Kant, but in this step, involving a change of focus on the transcendental field, more specifically on the transcendental foundation of temporality.

Este artigo enfoca o modo como a teoria husserliana da lembrança se insere, por um lado, na estrutura significativa formulada primeiramente nas Investigações lógicas e, por outro, nos moldes da percepção como unidade temporal. Para tanto, apresenta-se, respectivamente na primeira e na segunda seções, o arcabouço das teorias husserlianas da significação e da percepção como retenção. Na terceira seção, é analisada a segunda forma de lembrança — a rememoração —, segundo o fio condutor em que Husserl a investiga nos contextos da atenção, retenção, afecção e inconsciente. Finalmente, será considerado se o núcleo teórico da primazia do significado e do fluxo da consciência é, de fato, uma base propícia para a compreensão da lembrança em seu caráter de signo. --------------------------------------------------------------------------- This paper focuses on how Husserl's theory of memory is introduced, both in his significant structure, that was first formulated in the Logical Investigations and in the patterns of perception as a temporal unit. The first and second sections show, respectively, the framework of Husserl's theories of meaning and perception as retention. In the third section, the second mode of memory — recollection — is analyzed according to the thread that Husserl investigates in the contexts of attention, retention, affection and unconscious. Finally, we will consider whether the theoretical core of the primacy of meaning and the flow of consciousness is, in fact, an adequate basis for the comprehension of memory as a sign.

RESUMO: Este texto aborda alguns trabalhos contemporâneos em artes visuais que apresentam diferentes relações e disposições de um material dito natural: pedras. Ao retomar as distinções explicitadas por Heidegger, entre meras coisas, utensílio e obra de arte, bem como entre a pedra, o animal e o homem em relação ao mundo, serão discutidos deslocamentos acerca dessas distinções, com base em apontamentos da desconstrução. Pretende-se indicar alguns dos sentidos em que os enfoques desconstrutivos são frutíferos, para se pensar movimentos contemporâneos no âmbito do que Derrida denomina artes do espaço. ABSTRACT: This text approaches some contemporary works in the visual arts which present different relations and dispositions of a material taken to be natural: stone. I intend to revisit the distinctions presented by Heidegger between mere things, utensils and works of art, as well as between stone, animal and man in connection with the world. Furthermore, I will discuss dislocations regarding such issues, based on indications from deconstruction. I aim to indicate some of the meanings under which deconstructive approaches are fruitful for thinking about contemporary movements within the scope of what Derrida calls "spatial arts".