Localisation of light in disordered lattices

A short review of the basic concepts underlying localisation of light through multiple scattering in disordered media is provided, in conjunction with the ideas related to the universal features occurring during transport of waves and Anderson localisation. Progress in the area is described, including the recent experimental observation of localisation in photonic lattices upon which random perturbations are superimposed, which has constituted the first observation of Anderson localisation in any perturbed periodic system. Subsequently, some of the new intriguing concepts in the field of localisation of light are discussed, among them the combination of nonlinearity and disorder, and their effects on waves transport. Finally, being somewhat speculative, future directions in the area and their potential impact on the basic understanding of the universal phenomena associated with transport of waves are suggested.     

Generalized linear item response theory.

Generalized linear item response theory is discussed, which is based on the following assumptions: (1) A distribution of the response occurs according to given item format; (2) the item responses are explained by 1 continuous or nominal latent variable and p latent as well as observed variables that are continuous or nominal; (3) the responses to the different items of a test are independently distributed given the values of the explanatory variables; and (4) a monotone differentiable function g of the expected item response τ is needed such that a linear combination of the explanatory variables is a predictor of g(τ). It is shown that most of the well-known psychometric models are special cases of the generalized theory and that concepts such as differential item functioning, specific objectivity, reliability, and information can be subsumed under the generalized theory. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Biliary atresia and biliary cysts

The authors present a review of the classification, aetiology, presentation, treatment and long-term outcome of children and adults with biliary atresia and choledochal cyst disease. Biliary atresia should be suspected in any infant with jaundice beyond the second week of life. Although the aetiology and pathogenesis remain unclear, early management with portoenterostomy has significantly improved the course of this disease. Recent advances in immunosuppression have made liver transplantation a valuable and necessary adjunct to biliary bypass. With choledochal cyst disease, adults, unlike children, often present with acute biliary tract symptoms or pancreatitis. The treatment of choice remains extrahepatic cyst excision and biliary bypass. This treatment has excellent long-term results that minimize the development of malignancy.     

Line narrowing and self frequency scanning of laser diode arrayscoupled to a photorefractive oscillator

Line narrowing and self frequency scanning of a laser diode array coupled to a photorefractive passive-phase conjugate mirror has been demonstrated. Single-longitudinal mode operation is obtained and the coupling mechanism is discussed     

FNS Parameter Selection and Upper Limb Characterzation

The design of a controller for functional neuromuscular stimulation requires characterization of the plant, i. e., the neuromuscular system involved. The present paper is concerned with the modeling and identification of the elbow flexion/extension and wrist pronation/supination systems. These movements can be performed successfully by the surface stimulation of the biceps, triceps, and pronator teres. The scatter in the plant parameters between subjects and for a given subject as a function of time, electrode placement, etc., is outlined. The nonlinear muscle gain is approximated by a threshold below which the torque is zero, followed by a linear region. A least squares identification technique using a pseudorandom binary sequence input returned best fit for a third-order model for both the elbow and wrist dynamics. The dependence of the complex poles on the input signal bandwidth and level of coactivation is examined. The differences in parameters between the wrist and elbow systems are calculated. The results are used to establish design requirements for an appropriate controller.     

Families and Networks of Internet Memes: The Relationship Between Cohesiveness,Uniqueness, and Quiddity Concreteness

This study employs a large‐scale quantitative analysis to reveal structural patterns of internet memes, focusing on 2 forces that bind them together: the quiddities of each meme family and the generic attributes of the broader memetic sphere. Using content and network analysis of 1013 meme instances (including videos, images, and text), we explore memes' prevalent quiddity types and generic features, and the ways in which they relate to each other. Our findings show that (a) higher cohesiveness of meme families is associated with a greater uniqueness of their generic attributes; and (b) the concreteness of meme quiddities is associated with cohesiveness and uniqueness. We discuss the implications of these findings to the understanding of internet memes and participatory culture.     

New approach to return-oriented programming exploitation mitigation

Preventing software exploitation is an incredibly important goal for cyber security professionals, and huge amounts of time, effort, and money are devoted to this cause worldwide. A key stage of the exploitation process is gaining control of the execution flow of a target process so as to redirect it to the attacker’s illicit shellcode; most of the exploit mitigations currently in use are targeted at increasing the difficulty of this act. This article presents a new method for preventing control flow hijacking that provides a more robust defensive posture than existing options and is achieved by dereferencing function and return pointers to evaluate their contents rather than the extant approach of evaluating the pointers themselves.     

On the applicability of word sense discrimination on 201 years of modern english

As language evolves over time, documents stored in long- term archives become inaccessible to users. Automatically, detecting and handling language evolution will become a necessity to meet user’s information needs. In this paper, we investigate the performance of modern tools and algorithms applied on modern English to find word senses that will later serve as a basis for finding evolution. We apply the curvature clustering algorithm on all nouns and noun phrases extracted from The Times Archive (1785–1985). We use natural language processors for part-of-speech tagging and lemmatization and report on the performance of these processors over the entire period. We evaluate our clusters using WordNet to verify whether they correspond to valid word senses. Because The Times Archive contains OCR errors, we investigate the effects of such errors on word sense discrimination results. Finally, we present a novel approach to correct OCR errors present in the archive and show that the coverage of the curvature clustering algorithm improves. We increase the number of clusters by 24 %. To verify our results, we use the New York Times corpus (1987–2007), a recent collection that is considered error free, as a ground truth for our experiments. We find that after correcting OCR errors in The Times Archive, the performance of word sense discrimination applied on The Times Archive is comparable to the ground truth.     

Quantitative recovery of high purity nanoporous silica from waste products of the phosphate fertilizer industry

This study reports on the quantitative recovery of high purity nanoporous silica from wastes material (H₂SiF₆) of the phosphate fertilizer industry and Na₂O·SiO₂. The silica recovered from the wastes was compared with silica from the reaction of H₂SO₄ and Na₂O·SiO₂ because H₂SO₄ is commonly used. The product recovered from the wastes material and H₂SO₄ were 99.3% and 99.1% pure, respectively. The quantity recovered were 22.30 g and 20.11 g, respectively. The product had superior properties suitable for applications such as chromatography, reinforcing material for rubber and plastics. The process may significantly reduce the release of SiF₄ gas into the environment.