Visual Attention for Region of Interest Coding in JPEG 2000

This paper details work undertaken on the application of an algorithm for visual attention (VA) to region of interest (ROI) coding in JPEG 2000 (JP2K). In this way, an "interest ordered" progressive bit-stream is produced where the regions highlighted by the VA algorithm are presented first in bit-stream. The paper briefly outlines the terminology used in JP2K, the packet structure of the bit-stream, and the methods available to achieve ROI coding in JP2K (tiling, coefficient scaling, and code-block selection). The paper then describes how the output of the VA algorithm is post-processed so that an ROI is produced that can be efficiently coded using coefficient scaling in JP2K. Finally, a two alternative forced choice (2AFC) visual trial is undertaken to compare the visual quality of images encoded using the proposed VA ROI algorithm and conventional JP2K. The experimental results show that, while there is no overall preference for the VA ROI encoded images; there is an improvement in perceived image quality at low bit rates (below 0.25 bits per pixel). It is concluded that an overall increase in image quality only occurs when the increase in quality of the ROI more than compensates for the decrease in quality of the image background (i.e., non-ROI)

Synthesis of DBpin using Earth-abundant metal catalysis

The synthesis of DBpin was achieved using (EtBIP)CoCl2 or (tBuPNN)FeCl2 as pre-catalysts activated with NaOtBu. (EtBIP)CoCl2 was used as a pre-catalyst for the hydrogen isotope exchange of HBpin with D2, and (tBuPNN)FeCl2 for deuterogenolysis of B2pin2. The one-pot, tandem hydrogenolysis-hydroboration/deuterogenolysis-deuteroboration reaction of terminal alkenes could be catalysed by (tBuPNN)FeCl2 to give alkyl boronic esters

Pliocene-Pleistocene basin evolution along the Garlock fault zone, Pilot Knob Valley, California

Exposed Pliocene-Pleistocene terrestrial strata provide an archive of the spatial and temporal development of a basin astride the sinistral Garlock fault in California. In the southern Slate Range and Pilot Knob Valley, an ~2000-m-thick package of Late Cenozoic strata has been uplifted and tilted to the northeast. We name this succession the formation of Pilot Knob Valley and provide new chronologic, stratigraphic, and provenance data for these rocks. The unit is divided into five members that record different source areas and depositional patterns: (1) the lowest exposed strata are conglomeratic rocks derived from Miocene Eagle Crags volcanic field to the south and east across the Garlock fault (2) the second member consists mostly of fine-grained rocks with coarser material derived from both southern and northern sources; and (3) the upper three members are primarily coarse-grained conglomerates and sandstones derived from the adjacent Slate Range to the north. Tephrochronologic data from four ash samples bracket deposition of the second member to 3.6-3.3 Ma and the fourth member to between 1.1 and 0.6 Ma. A fifth tephrochronologic sample from rocks south of the Garlock fault near Christmas Canyon brackets deposition of a possible equivalent to the second member of the formation of Pilot Knob Valley at ca. 3.1 Ma. Although the age of the base of the lowest member is not directly dated, regional stratigraphic and tectonic associations suggest that the basin started forming ca. 4-5 Ma. By ca. 3.6 Ma, the northward progradation fanglomerate sourced in the Eagle Crags region waned, and subsequent deposition occurred in shallow lacustrine systems. At ca. 3.3 Ma, southward progradation of conglomerates derived from the Slate Range began. Circa 1.1 Ma, continued southward progradation of fanglomerate with Slate Range sources is characterized by a shift to coarser grain sizes, interpreted to reflect uplift of the Slate Range. Overall, basin architecture and the temporal evolution of different source regions were controlled by activity on three regionally important faults-the Garlock, the Marine Gate, and the Searles Valley faults. The timing and style of motions on these faults appear to be directly linked to patterns of basin development

Immune sensing of Candida albicans requires cooperative recognition of mannans and glucans by lectin and Toll-like receptors

Peer reviewedPublisher PD

On the relationship between continuous- and discrete-time quantum walk

Quantum walk is one of the main tools for quantum algorithms. Defined by analogy to classical random walk, a quantum walk is a time-homogeneous quantum process on a graph. Both random and quantum walks can be defined either in continuous or discrete time. But whereas a continuous-time random walk can be obtained as the limit of a sequence of discrete-time random walks, the two types of quantum walk appear fundamentally different, owing to the need for extra degrees of freedom in the discrete-time case. In this article, I describe a precise correspondence between continuous- and discrete-time quantum walks on arbitrary graphs. Using this correspondence, I show that continuous-time quantum walk can be obtained as an appropriate limit of discrete-time quantum walks. The correspondence also leads to a new technique for simulating Hamiltonian dynamics, giving efficient simulations even in cases where the Hamiltonian is not sparse. The complexity of the simulation is linear in the total evolution time, an improvement over simulations based on high-order approximations of the Lie product formula. As applications, I describe a continuous-time quantum walk algorithm for element distinctness and show how to optimally simulate continuous-time query algorithms of a certain form in the conventional quantum query model. Finally, I discuss limitations of the method for simulating Hamiltonians with negative matrix elements, and present two problems that motivate attempting to circumvent these limitations.Comment: 22 pages. v2: improved presentation, new section on Hamiltonian oracles; v3: published version, with improved analysis of phase estimatio

Standing-Wave Free-Electron Laser Two-Beam Accelerator

A free-electron laser (FEL) two-beam accelerator (TBA) is proposed, in which the FEL interaction takes place in a series of drive cavities, rather than in a waveguide. Each drive cavity is 'beat-coupled' to a section of the accelerating structure. This standing-wave TBA is investigated theoretically and numerically, with analyses included of microwave extraction, growth of the FEL signal through saturation, equilibrium longitudinal beam dynamics following saturation, and sensitivity of the microwave amplitude and phase to errors in current and energy. It is found that phase errors due to current jitter are substantially reduced from previous versions of the TBA. Analytic scalings and numerical simulations are used to obtain an illustrative TBA parameter set

The psychological burden of skin diseases: a cross-sectional multicenter study among dermatological out-patients in 13 European countries.

The contribution of psychological disorders to the burden of skin disease has been poorly explored, and this is a large-scale study to ascertain the association between depression, anxiety, and suicidal ideation with various dermatological diagnoses. This international multicenter observational cross-sectional study was conducted in 13 European countries. In each dermatology clinic, 250 consecutive adult out-patients were recruited to complete a questionnaire, reporting socio-demographic information, negative life events, and suicidal ideation; depression and anxiety were assessed with the Hospital Anxiety and Depression Scale. A clinical examination was performed. A control group was recruited among hospital employees. There were 4,994 participants--3,635 patients and 1,359 controls. Clinical depression was present in 10.1% patients (controls 4.3%, odds ratio (OR) 2.40 (1.67-3.47)). Clinical anxiety was present in 17.2% (controls 11.1%, OR 2.18 (1.68-2.82)). Suicidal ideation was reported by 12.7% of all patients (controls 8.3%, OR 1.94 (1.33-2.82)). For individual diagnoses, only patients with psoriasis had significant association with suicidal ideation. The association with depression and anxiety was highest for patients with psoriasis, atopic dermatitis, hand eczema, and leg ulcers. These results identify a major additional burden of skin disease and have important clinical implications.Peer reviewedFinal Published versio

Centrifuge modelling of screw piles for offshore wind energy foundations

Screw piles (helical piles) can provide a viable, cost-effective and low-noise installation alternative to increasing the size of existing foundation solutions (e.g. monopiles) to meet the demand for the advancement of offshore wind energy into deeper water. Significant upscaling of widely used onshore screw pile geometries will be required to meet the loading conditions of a jacket supported offshore wind turbine. This increase in size will lead to greater installation force and torque. This paper presents preliminary results from centrifuge tests investigating the requirements to install screw piles designed for an offshore wind energy application using specially developed equipment. Results indicate that the equipment is suitable to investigate these screw pile requirements and that significant force is required for such upscaled screw piles, with 19 MN vertical force and 7 MNm torque for the standard design. Optimisation of the screw pile geometry, reduced these forces by 29 and 11% for the vertical and rotational forces respectively

Steps to Develop Early Warning Systems and Future Scenarios of Storm Wave-Driven Flooding Along Coral Reef-Lined Coasts

ABSTRACT: Tropical coral reef-lined coasts are exposed to storm wave-driven flooding. In the future, flood events during storms are expected to occur more frequently and to be more severe due to sea-level rise, changes in wind and weather patterns, and the deterioration of coral reefs. Hence, disaster managers and coastal planners are in urgent need of decision-support tools. In the short-term, these tools can be applied in Early Warning Systems (EWS) that can help to prepare for and respond to impending storm-driven flood events. In the long-term, future scenarios of flooding events enable coastal communities and managers to plan and implement adequate risk-reduction strategies. Modeling tools that are used in currently available coastal flood EWS and future scenarios have been developed for open-coast sandy shorelines, which have only limited applicability for coral reef-lined shorelines. The tools need to be able to predict local sea levels, offshore waves, as well as their nearshore transformation over the reefs, and translate this information to onshore flood levels. In addition, future scenarios require long-term projections of coral reef growth, reef composition, and shoreline change. To address these challenges, we have formed the UFORiC (Understanding Flooding of Reef-lined Coasts) working group that outlines its perspectives on data and model requirements to develop EWS for storms and scenarios specific to coral reef-lined coastlines. It reviews the state-of-the-art methods that can currently be incorporated in such systems and provides an outlook on future improvements as new data sources and enhanced methods become available

Search for Higgs Bosons in e+e- Collisions at 183 GeV

The data collected by the OPAL experiment at sqrts=183 GeV were used to search for Higgs bosons which are predicted by the Standard Model and various extensions, such as general models with two Higgs field doublets and the Minimal Supersymmetric Standard Model (MSSM). The data correspond to an integrated luminosity of approximately 54pb-1. None of the searches for neutral and charged Higgs bosons have revealed an excess of events beyond the expected background. This negative outcome, in combination with similar results from searches at lower energies, leads to new limits for the Higgs boson masses and other model parameters. In particular, the 95% confidence level lower limit for the mass of the Standard Model Higgs boson is 88.3 GeV. Charged Higgs bosons can be excluded for masses up to 59.5 GeV. In the MSSM, mh > 70.5 GeV and mA > 72.0 GeV are obtained for tan{beta}>1, no and maximal scalar top mixing and soft SUSY-breaking masses of 1 TeV. The range 0.8 < tanb < 1.9 is excluded for minimal scalar top mixing and m{top} < 175 GeV. More general scans of the MSSM parameter space are also considered.Comment: 49 pages. LaTeX, including 33 eps figures, submitted to European Physical Journal