Lucia Lumbelli 1937-2019

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The Effect of the Context on the Anisotropy of the Visual Field

The phenomenal (visual) field is not homogeneous (anisotropic). Clear examples of this are given by Bartlett’s “replication experiments” and Blum’s “firegrass model”. In 1991, Stadler, Kruse, Richter and Pfaff attempted to develop a vector field model of the visual field, and on this basis, Kruse, Luccio, Pfaff and Stadler (1996) demonstrated relevant context effects introducing different directionally oriented shapes in the field. In this paper, we propose some methodological modifications, aimed to improve the consistency of the results

Perceptual Simplicity: The True Role of Prägnanz and Occam

Summary In recent years, the concept of simplicity in perception has acquired a leading role, above all thanks to scholars linked to Bayesian modeling and to theories like structural information theory derived from information theory. Unfortunately, two misleading ideas made their way into the discussion: that in perception, simplicity is equivalent to Prägnanz and that Occam's razor plays a role in the simplicity of percepts. Here it is shown that in Gestalt theory, simplicity is only one of the factors of Prägnanz and that the use of Occam's razor is improper, because it applies only to the theories that generate, in this case, a percept, and not to the product of the theory

Psychologia – the birth of a new scientific context

The use of the term soul was banned from the psychological vocabulary, at least since Angell’s famous interdict in 1911. This paper examines the various stages of the constitution of the domain of knowledge labelled psychologia since the 16th century, when the term psychologia was coined by the Dalmatian humanist Marko Marulić (Krstić, 1964). His treatise on the subject was unfortunately lost and the term was possibly “reinvented” in the Ramist field of philosophy. The first printed occurrence was in Freigius’ (1575), Snellius’ (1596a, b), and Casmann’s (1594) work, which is where the process of refinement of the subject area began. According to Ramists, all of the soul could be studied as a part of physics, and not only its lower components, as had been considered before that. While the great scholars of the mind, like Descartes, Leibniz, or Locke, ignored the term, psychologia had a clear development in the 17th and 18th century, mainly in medicine. Subsequently, Christian Wolff (1732) introduced empirical psychology in the 18th century, which is considered the very basis of the scientific psychology

Type-Based Analysis of Generic Key Management APIs

In the past few years, cryptographic key management APIs have been shown to be subject to tricky attacks based on the improper use of cryptographic keys. In fact, real APIs provide mechanisms to declare the intended use of keys but they are not strong enough to provide key security. In this paper, we propose a simple imperative programming language for specifying strongly-typed APIs for the management of symmetric, asymmetric and signing keys. The language requires that type information is stored together with the key but it is independent of the actual low-level implementation. We develop a type-based analysis to prove the preservation of integrity and confidentiality of sensitive keys and we show that our abstraction is expressive enough to code realistic key management APIs

Localizing Security for Distributed Firewalls

In complex networks, filters may be applied at different nodes to control how packets flow. In this paper, we study how to locate filtering functionality within a network. We show how to enforce a set of security goals while allowing maximal service subject to the security constraints. Our contributions include a way to specify security goals for how packets traverse the network and an algorithm to distribute filtering functionality to different nodes in the network to enforce a given set of security goals

Tube Expansion Deformation Enables In Situ Synchrotron X-ray Scattering Measurements during Extensional Flow-Induced Crystallization of Poly l-Lactide Near the Glass Transition

Coronary Heart Disease (CHD) is one of the leading causes of death worldwide, claiming over seven million lives each year. Permanent metal stents, the current standard of care for CHD, inhibit arterial vasomotion and induce serious complications such as late stent thrombosis. Bioresorbable vascular scaffolds (BVSs) made from poly l-lactide (PLLA) overcome these complications by supporting the occluded artery for 3–6 months and then being completely resorbed in 2–3 years, leaving behind a healthy artery. The BVS that recently received clinical approval is, however, relatively thick (~150 µm, approximately twice as thick as metal stents ~80 µm). Thinner scaffolds would facilitate implantation and enable treatment of smaller arteries. The key to a thinner scaffold is careful control of the PLLA microstructure during processing to confer greater strength in a thinner profile. However, the rapid time scales of processing (~1 s) defy prediction due to a lack of structural information. Here, we present a custom-designed instrument that connects the strain-field imposed on PLLA during processing to in situ development of microstructure observed using synchrotron X-ray scattering. The connection between deformation, structure and strength enables processing–structure–property relationships to guide the design of thinner yet stronger BVS