44 research outputs found

    A spatial dashboard for Alzheimer's disease in New South Wales

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    © 2017 The authors and IOS Press. This paper illustrates a proof of concept scenario for the application of comprehensive data visualisation methods in the rapidly changing aged care sector. The scenario we explored is population ageing and the dementias with an emphasis on the spatial effects of change over time at the Statistical Area 2 (SA2) level for the state of New South Wales. We did this using a combination of methods, culminating in the use of the Tableau software environment to explore the intersections of demography, epidemiology and their formal cost of care implications. In addition, we briefly illustrate how key infrastructure data can be included in the same data management context by showing how service providers can be integrated and mapped in conjunction with other analyses. This is an innovative and practical approach to some of the complex issues already faced in the health and aged care sectors which can only become more pronounced as population ageing progresses

    Deterministic and Probabilistic Binary Search in Graphs

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    We consider the following natural generalization of Binary Search: in a given undirected, positively weighted graph, one vertex is a target. The algorithm's task is to identify the target by adaptively querying vertices. In response to querying a node qq, the algorithm learns either that qq is the target, or is given an edge out of qq that lies on a shortest path from qq to the target. We study this problem in a general noisy model in which each query independently receives a correct answer with probability p>12p > \frac{1}{2} (a known constant), and an (adversarial) incorrect one with probability 1p1-p. Our main positive result is that when p=1p = 1 (i.e., all answers are correct), log2n\log_2 n queries are always sufficient. For general pp, we give an (almost information-theoretically optimal) algorithm that uses, in expectation, no more than (1δ)log2n1H(p)+o(logn)+O(log2(1/δ))(1 - \delta)\frac{\log_2 n}{1 - H(p)} + o(\log n) + O(\log^2 (1/\delta)) queries, and identifies the target correctly with probability at leas 1δ1-\delta. Here, H(p)=(plogp+(1p)log(1p))H(p) = -(p \log p + (1-p) \log(1-p)) denotes the entropy. The first bound is achieved by the algorithm that iteratively queries a 1-median of the nodes not ruled out yet; the second bound by careful repeated invocations of a multiplicative weights algorithm. Even for p=1p = 1, we show several hardness results for the problem of determining whether a target can be found using KK queries. Our upper bound of log2n\log_2 n implies a quasipolynomial-time algorithm for undirected connected graphs; we show that this is best-possible under the Strong Exponential Time Hypothesis (SETH). Furthermore, for directed graphs, or for undirected graphs with non-uniform node querying costs, the problem is PSPACE-complete. For a semi-adaptive version, in which one may query rr nodes each in kk rounds, we show membership in Σ2k1\Sigma_{2k-1} in the polynomial hierarchy, and hardness for Σ2k5\Sigma_{2k-5}

    Domain structure in CoFeB thin films with perpendicular magnetic anisotropy

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    Domain structures in CoFeB-MgO thin films with a perpendicular easy magnetization axis were observed by magneto-optic Kerr-effect microscopy at various temperatures. The domain wall surface energy was obtained by analyzing the spatial period of the stripe domains and fitting established domain models to the period. In combination with SQUID measurements of magnetization and anisotropy energy, this leads to an estimate of the exchange stiffness and domain wall width in these films. These parameters are essential for determining whether domain walls will form in patterned structures and devices made of such materials

    Reverse Doppler effect in backward spin waves scattered on acoustic waves

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    We report on the observation of reverse Doppler effect in backward spin waves reflected off of surface acoustic waves. The spin waves are excited in a yttrium iron garnet (YIG) film. Simultaneously, acoustic waves are also generated. The strain induced by the acoustic waves in the magnetostrictive YIG film results in the periodic modulation of the magnetic anisotropy in the film. Thus, in effect, a travelling Bragg grating for the spin waves is produced. The backward spin waves reflecting off of this grating exhibit a reverse Doppler shift: shifting down rather than up in frequency when reflecting off of an approaching acoustic wave. Similarly, the spin waves are shifted up in frequency when reflecting from receding acoustic waves.Comment: 4 pages, 3 figure

    On-line Algorithms for 2-Coloring Hypergraphs via Chip Games

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    Erdős has shown that for all k-hypergraphs with fewer than 2 k\Gamma1 edges, there exists a 2-coloring of the nodes so that no edge is monochromatic. Erdos has also shown that when the number of edges is greater than k 2 2 k+1 , there exist k-hypergraphs with no such 2-coloring. These bounds are not contructive, however. In this paper, we take an "on-line" look at this problem, showing constructive upper and lower bounds on the number of edges of a hypergraph which allow it to be 2-colored on-line. These bounds become particularly interesting for degree-k k-hypergraphs which always have a good 2-coloring for all k 10 by the Lovász Local Lemma. In this case, our upper bound demonstrates an inherent weakness of on-line strategies by constructing an adversary which defeats any on-line 2-coloring algorithm using degree-k k-hypergraph with (3 + 2 p 2) k edges

    Upflow anaerobic sludge blanket reactor - a review

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    On-line Algorithms for 2-Coloring Hypergraphs via Chip Games

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    Erdös has shown that for all k-hypergraphs with fewer than 2 k−1 edges, there exists a 2-coloring of the nodes so that no edge is monochromatic. Erdös has also shown that when the number of edges is greater than k 2 2 k+1, there exist k-hypergraphs with no such 2-coloring. These bounds are not constructive, however. In this paper, we take an “on-line ” look at this problem, showing constructive upper and lower bounds on the number of edges of a hypergraph which allow it to be 2-colored on-line. These bounds become particularly interesting for degree-k k-hypergraphs which always have a good 2-coloring for all k ≥ 10 by the Lovász Local Lemma. In this case, our upper bound demonstrates an inherent weakness of on-line strategies by constructing an adversary which defeats any on-line 2-coloring algorithm using degree-k k-hypergraph with (3 + 2 √ 2) k edges

    Polymer thin film transistor without surface pretreatment on silicon nitride gate dielectric

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    It is well known that surface modification of the gate dielectric in organic thin film transistors (TFTs) plays an important role in device performance, often giving rise to severalfold improvements in field-effect mobility. This paper reports on solution-processed polymer TFTs with mobilities comparable to high performance counterparts despite the absence of dielectric surface pretreatment. An effective mobility of 0.1 cm2 V s was obtained with poly(2,5-bis(3-dodecylthiophene-2-yl)thieno[3,2-b]thiophene) transistors on silicon nitride gate dielectric. The results indicate that by judicious preparation of the device layers, one can mitigate the need for dielectric surface pretreatment, thereby reducing fabrication complexity without compromising TFT performance. © 2008 American Institute of Physics

    The GM-CSF/IL-3/IL-5 cytokine receptor family: from ligand recognition to initiation of signaling

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    Granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and IL-5 are members of a discrete family of cytokines that regulates the growth, differentiation, migration and effector function activities of many hematopoietic cells and immunocytes. These cytokines are involved in normal responses to infectious agents, bridging innate and adaptive immunity. However, in certain cases, the overexpression of these cytokines or their receptors can lead to excessive or aberrant initiation of signaling resulting in pathological conditions, with chronic inflammatory diseases and myeloid leukemias the most notable examples. Recent crystal structures of the GM-CSF receptor ternary complex and the IL-5 binary complex have revealed new paradigms of cytokine receptor activation. Together with a wealth of associated structure-function studies, they have significantly enhanced our understanding of how these receptors recognize cytokines and initiate signals across cell membranes. Importantly, these structures provide opportunities for structure-based approaches for the discovery of novel and disease-specific therapeutics. In addition, recent biochemical evidence has suggested that the GM-CSF/IL-3/IL-5 receptor family is capable of interacting productively with other membrane proteins at the cell surface. Such interactions may afford additional or unique biological activities and might be harnessed for selective modulation of the function of these receptors in disease.Sophie E. Broughton, Urmi Dhagat, Timothy R. Hercus, Tracy L. Nero, Michele A. Grimbaldeston, Claudine S. Bonder, Angel F. Lopez, Michael W. Parke
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