An active curve approach for tomographic reconstruction of binary radially symmetric objects

This paper deals with a method of tomographic reconstruction of radially symmetric objects from a single radiograph, in order to study the behavior of shocked material. The usual tomographic reconstruction algorithms such as generalized inverse or filtered back-projection cannot be applied here because data are very noisy and the inverse problem associated to single view tomographic reconstruction is highly unstable. In order to improve the reconstruction, we propose here to add some a priori assumptions on the looked after object. One of these assumptions is that the object is binary and consequently, the object may be described by the curves that separate the two materials. We present a model that lives in BV space and leads to a non local Hamilton-Jacobi equation, via a level set strategy. Numerical experiments are performed (using level sets methods) on synthetic objects

A New Technique for Sampling Multi-Modal Distributions

In this paper we demonstrate that multi-modal Probability Distribution Functions (PDFs) may be efficiently sampled using an algorithm originally developed for numerical integrations by Monte-Carlo methods. This algorithm can be used to generate an input PDF which can be used as an independence sampler in a Metropolis-Hastings chain to sample otherwise troublesome distributions.Some examples in one two and five dimensions are worked out.Comment: One ps figure; submitted to "Journal of Computational Physics

Antibacterial marine bacterium deter luminous vibriosis in shrimp larvae

Inhibitory activity of a marine pigmented bacterium - Alteromonas sp. - isolated from Penaeus monodon Fabricius larva against pathogenic and environmental isolates of Vibrio harveyi was studied. All the isolates were inhibited to varying degrees by Alteromonas sp. in vitro. The antibacterial substance produced by the Alteromonas sp. was soluble in organic solvent and closely bound to the external surface of bacterial cells. The antibacterial Alteromonas sp., when allowed to colonize on shrimp larvae, suppressed the activity of V. harveyi M3 and reduced mortality of P. monodon larvae in vivo

Quantum Programs as Kleisli Maps

Furber and Jacobs have shown in their study of quantum computation that the category of commutative C*-algebras and PU-maps (positive linear maps which preserve the unit) is isomorphic to the Kleisli category of a comonad on the category of commutative C*-algebras with MIU-maps (linear maps which preserve multiplication, involution and unit). [Furber and Jacobs, 2013] In this paper, we prove a non-commutative variant of this result: the category of C*-algebras and PU-maps is isomorphic to the Kleisli category of a comonad on the subcategory of MIU-maps. A variation on this result has been used to construct a model of Selinger and Valiron's quantum lambda calculus using von Neumann algebras. [Cho and Westerbaan, 2016]Comment: In Proceedings QPL 2016, arXiv:1701.0024

Bias Crime: A Call for Alternative Responses

The argument for enacting laws to punish and deter bias crime does not always benefit from clear and unambiguous examples of bias driven murder. A frustrating factor in some of the widely publicized reports of bias-related assault is the element of ambiguity: where a member of one race or religion injures a member of another race or religion, even perhaps articulating the difference between attacker and victim by means of an expletive or other statement, the question inevitably arises whether the attack was the product of bias alone, or did other factors, such as an intent to rob or rape, predominate. This article advocates a renewed legislative effort in the fight against bias crime. The difficulty that attaches to defining a crime of bias, and to identifying the categories to be included in the statute, is far outweighed by the urgency of the escalating problem. In addition to the present remedial scheme, varied approaches need to be fostered and accentuated including non-penal sanctions. Proposed statutes in New York take a stronger stance on identifying and punishing bias crime incidents. Even more important than a successful conviction rate is the development of effective education and community responses to intolerance and prejudice

Creative thinking as orchestrated by semantic processing vs. cognitive control brain networks.

Creativity is primarily investigated within the neuroscientific perspective as a unitary construct. While such an approach is beneficial when trying to infer the general picture regarding creativity and brain function, it is insufficient if the objective is to uncover the information processing brain mechanisms by which creativity occurs. As creative thinking emerges through the dynamic interplay between several cognitive processes, assessing the neural correlates of these operations would enable the development and characterization of an information processing framework from which to better understand this complex ability. This article focuses on two aspects of creative cognition that are central to generating original ideas. "Conceptual expansion" refers to the ability to widen one's conceptual structures to include unusual or novel associations, while "overcoming knowledge constraints" refers to our ability to override the constraining influence imposed by salient or pertinent knowledge when trying to be creative. Neuroimaging and neuropsychological evidence is presented to illustrate how semantic processing and cognitive control networks in the brain differentially modulate these critical facets of creative cognition