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Papanikolaou S.,Cornell University | Betouras J.J.,The North Alliance
Physical Review Letters

We study the phase transition between the Coulomb liquid and the columnar crystal in the 3D classical dimer model, which was found to be continuous in the O(3) universality class. In addition to nearest-neighbor interactions which favor parallel dimers, further neighbor interactions are allowed in such a manner that the cubic symmetry of the original system remains intact. We show that the transition in the presence of weak additional, symmetry preserving interactions is first order. However, the universality class of the transition remains continuous when the additional interactions are weakly repulsive. In this way, we verify the existence of a multicritical point near the unperturbed transition, and we identify a critical line of unconventional transitions between the Coulomb liquid phase and the sixfold columnar phase. © 2010 The American Physical Society. Source

Kurer M.A.,Colorectal Unit | Davey C.,The North Alliance | Khan S.,Scarborough Hospital | Chintapatla S.,Colorectal Unit
Colorectal Disease

Aim: To perform a systematic review of the published reports on retained colorectal foreign bodies (CFBs) to collate the features and formulate a simple management plan based on the available evidence. Method: An extensive search was carried out to identify articles on CFBs. The search was carried out on electronic databases Cinahl, Embase, Medline, PubMed and PsychInfo from 1950 to January 2009. Internet journals were also scoured and a general search was carried out using the search engine 'Google'. Papers published in languages other than English were not included. Results: This review covers a total of 193 patients with 196 presentations. There were 188 men and 5 women, a ratio of approximately 37:1. The mean age at presentation was 44.1 years (SD 16.6) in the single case reports and 39.3, 40 and 60.8 years in the three case series. Household objects, such as bottles and glasses, accounted for the largest percentage (42.2%) of inserted objects. Presentation for treatment occurred most often within 24 h of insertion and the majority of objects were removed transanally using manual manipulation with or without the use of a variety of tools, or via a scope. Conclusions: The incidence of CFBs is disproportionately higher in men. Various techniques for removal are available, including some that are minimally invasive. The appropriate technique will depend on the size and surface of the retained object and the presence of complications such as perforation or obstruction. © 2010 The Authors. Journal Compilation © 2010 The Association of Coloproctology of Great Britain and Ireland. Source

Wilson S.M.,University of Maryland University College | Fraser-Rahim H.,The North Alliance | Williams E.,University of South Carolina | Zhang H.,University of South Carolina | And 3 more authors.
American Journal of Public Health

Objectives. We assessed spatial disparities in the distribution of Toxic Release Inventory (TRI) facilities in Charleston, SC. Methods. We used spatial methods and regression to assess burden disparities in the study area at the block and census-tract levels by race/ethnicity and socioeconomic status (SES). Results. Results revealed an inverse relationship between distance to TRI facilities and race/ethnicity and SES at the block and census-tract levels. Results of regression analyses showed a positive association between presence of TRI facilities and high percentage non-White and a negative association between number of TRI facilities and high SES. Conclusions. There are burden disparities in the distribution of TRI facilities in Charleston at the block and census-tract level by race/ethnicity and SES. Additional research is needed to understand cumulative risk in the region. Source

Clark K.B.,Research and Development Service | Clark K.B.,The North Alliance
Frontiers in Molecular Neuroscience

Grover's quantum (search) algorithm exploits principles of quantum information theory and computation to surpass the strong Church-Turing limit governing classical computers. The algorithm initializes a search field into superposed N (eigen)states to later execute nonclassical "subroutines" involving unitary phase shifts of measured states and to produce root-rate or quadratic gain in the algorithmic time (O (N 1/2)) needed to find some "target" solution m. Akin to this fast technological search algorithm, single eukaryotic cells, such as differentiated neurons, perform natural quadratic speed-up in the search for appropriate store-operated Ca2+ response regulation of, among other processes, protein and lipid biosynthesis, cell energetics, stress responses, cell fate and death, synaptic plasticity, and immunoprotection. Such speed-up in cellular decision making results from spatiotemporal dynamics of networked intracellular Ca2+-induced Ca2+ release and the search (or signaling) velocity of Ca2+ wave propagation. As chemical processes, such as the duration of Ca2+mobilization, become rate-limiting over interstore distances, Ca2+ waves quadratically decrease interstore-travel time from slow saltatory to fast continuous gradients proportional to the square-root of the classical Ca2+ diffusion coefficient, D 1/2, matching the computing efficiency of Grover's quantum algorithm. In this Hypothesis and Theory article, I elaborate on these traits using a fire-diffuse-fire model of store-operated cytosolic Ca2+ signaling valid for glutamatergic neurons. Salient model features corresponding to Grover's quantum algorithm are parameterized to meet requirements for the Oracle Hadamard transform and Grover's iteration. A neuronal version of Grover's quantum algorithm figures to benefit signal coincidence detection and integration, bidirectional synaptic plasticity, and other vital cell functions by rapidly selecting, ordering, and/or counting optional response regulation choices. © 2014 Clark. Source

The North Alliance | Date: 2011-02-17

Inventory management methods are provided. In one embodiment, an inventory management method includes receiving an indication of a received product. Available spaces in a warehouse picking area that can store the received product are determined. The received product is stored to one of the spaces, and the space is later reused to store a different product. In another embodiment, a plurality of available spaces for storing a product in a warehouse picking area is determined. The plurality of available spaces includes spaces that have different shapes. An indication of the available spaces and their locations in the warehouse picking area is provided.

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