Dynamic Ordering for Asynchronous Backtracking on DisCSPs

An algorithm that performs asynchronous backtracking on distributed , with dynamic ordering of agents is proposed, . Agents propose reorderings of lower priority agents and send these proposals whenever they send assignment messages. Changes of ordering triggers a different computation of . The dynamic ordered asynchronous backtracking algorithm uses polynomial space, similarly to standard . The algorithm with three different ordering heuristics is compared to standard on randomly generated . A Nogood-triggered heuristic, inspired by dynamic backtracking, is found to outperform static order by a large factor in run-time and improve the network load.     

Detection and reduction of evolutionary noise in correlated mutation analysis

Direct or indirect inter-residue interactions in proteins are often reflected by mutations at one site that compensate for mutations at another site. Various bioinformatic methods have been developed for detecting such correlated mutations in order to obtain information about intra- and inter-protein interactions. Here, we show by carrying out a correlated mutation analysis for non-interacting proteins that the signal due to inter-residue interactions is of similar magnitude to the 'noise' that arises from other evolutionary processes related to common ancestry. A new method for detecting correlated mutations is presented that reduces this evolutionary noise by taking into account evolutionary distances in the protein family. It is shown that this method yields better signal-to-noise ratios and, therefore, can much better resolve, for example, correlated mutations that reflect true inter-residue interactions.     

Immersion and invariance based fault tolerant adaptive spacecraft attitude control

In this paper, an immersion and invariance (I&I) adaptive fault tolerant satellite attitude tracking control scheme is proposed. The proposed controller is capable of track the desired trajectory in the presence of unknown actuator multiplicative faults and unknown inertial matrix. Also based on Lyapunov direct method, all closed loop signals are proven to be globally asymptotically stable. The main advantage of this controller is improving closed loop performance while maintaining stability in the presence of unknown actuator faults. This method does not rely on certainty equivalence principle so it can be used to control the transient response of overall closed loop system by means of controlling the parameter estimation behavior which is not possible in traditional adaptive control. Numerical simulations are performed to demonstrate the effectiveness of proposed control scheme.     

Identification of informal reasoning fallacies as a function of epistemological level, grade level, and cognitive ability.

Informal reasoning fallacies are violations of critical discussion norms. As epistemological understanding of knowledge justification appears to underlie the informal reasoning skills of argument construction and evaluation, it was hypothesized that adolescents with greater epistemological sophistication would be more able to identify informal reasoning fallacies. It was hypothesized that 11th graders would be more epistemologically sophisticated than 7th or 9th graders and, thus, would more likely identify fallacies. Students responded to questions regarding argument scenarios that did or did not contain fallacies. More 11th graders identified fallacies. Epistemological level predicted only identification of one type of fallacy that might be described as epistemological in nature. Cognitive ability also seemed to contribute to the increased ability with grade to identify fallacies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Multiple View Geometry of General Algebraic Curves

We introduce a number of new results in the context of multi-view geometry from general algebraic curves. We start with the recovery of camera geometry from matching curves. We first show how one can compute, without any knowledge on the camera, the homography induced by a single planar curve. Then we continue with the derivation of the extended Kruppa's equations which are responsible for describing the epipolar constraint of two projections of a general algebraic curve. As part of the derivation of those constraints we address the issue of dimension analysis and as a result establish the minimal number of algebraic curves required for a solution of the epipolar geometry as a function of their degree and genus.We then establish new results on the reconstruction of general algebraic curves from multiple views. We address three different representations of curves: (i) the regular point representation in which we show that the reconstruction from two views of a curve of degree d admits two solutions, one of degree d and the other of degree d(d – 1). Moreover using this representation, we address the problem of homography recovery for planar curves, (ii) dual space representation (tangents) for which we derive a lower bound for the number of views necessary for reconstruction as a function of the curve degree and genus, and (iii) a new representation (to computer vision) based on the set of lines meeting the curve which does not require any curve fitting in image space, for which we also derive lower bounds for the number of views necessary for reconstruction as a function of curve degree alone.     

Octa-O-bis-(R,R)-Tartarate Ditellurane (SAS) - a novel bioactive organotellurium(IV) compound: synthesis, characterization, and protease inhibitory activity

Octa-O-bis-(R,R)-Tartarate Ditellurane (SAS) is a new Te(IV) compound, comprised of two tellurium atoms, each liganded by four oxygen atoms from two carboxylates and two alkoxides of two tartaric acids. Unlike many other Te(IV) compounds, SAS was highly stable in aqueous solution. It interacted with thiols to form an unstable Te(SR)(4) product. The product of the interaction of SAS with cysteine was isolated and characterized by mass spectroscopy and elemental analysis. SAS selectively inactivated cysteine proteases, but it did not inactivate other families of proteolytic enzymes. It displayed selectivity towards the cysteine protease cathepsin B, a human enzyme of pharmaceutical interest, with a second order rate constant k(i)/K(i)=5900 M(-1) s(-1).     

Some Philosophical Issues in Computer Science

The essays included in the special issue dedicated to the philosophy of computer science examine new philosophical questions that arise from reflection upon conceptual issues in computer science and the insights such an enquiry provides into ongoing philosophical debates.     

Optimal salting of macadamia (Macadamia integrifolia) nuts

Roasted macadamia (Macadamia integrifolia Storey) nuts were salted at various levels up to 19 g kg^?1 and presented to a taste panel. The results showed that the assessors could be divided into 'salt dislikers', to whom perceived quality decreased linearly with increase in salt content, and 'salt likers', to whom perceived quality increased as the salt content increased. It follows that the nuts can be produced to suit these two market segments separately, or else a single lightly salted compromise product can be offered to both groups.     

The Effects of Mutations on Protein Function: A Comparative Study of Three Databases of Mutations in Humans

Single-nucleotide mutations (SNPs) in protein-coding regions of the human genome are a major factor in determining human variation in health and disease. Here, we analyze the amino acid changes and functional effects due to non-synonymous SNPs. Three databases were used: (i) Variation – mutations found in the general human population; (ii) Cosmic – mutations found in cancer cells; and (iii) Pathogenic – a curated subset of mutations in Variation that are associated with diseases. The distributions of amino acid changes in these datasets were analyzed. It is shown that mutations in the Pathogenic dataset, in particular, tend to introduce order-promoting residues. The effects of the mutations in these datasets were also studied using the program Polyphen-2, which predicts the functional impact of non-synonymous mutations. In order to evaluate the significance of these predicted effects, we compared them to those due to the same amino acid replacements introduced at other positions in the same proteins as a control. A mutation can be deleterious because the amino acid change is drastic (for example a change from hydrophobic residue to hydrophilic residue) or because of its location in the protein. We found that, on both counts, mutations in the Variation dataset tend to be less deleterious than randomly expected whereas mutations in the Pathogenic dataset tend to be more deleterious than their control mutations. The mutations in the Cosmic dataset are found to be more deleterious than those in its control set but less than those in Pathogenic.