A Network Model of Alcoholism and Alcohol Policy

The evolution of alcohol dependence in populations of people on different social networks is studied. Two models are studied. One is the evolution of the states of individuals on hypothesized social structures from a rewired connected caveman model. This model spans a range of social structures (networks) from very ordered to effectively random with small world structures in between. The second model is a zip-code-level model which uses data from a recent survey in Delaware. The model is a discrete model using 10 zip codes. The results show that the evolution of alcohol dependence, as governed by the simple rules that we use, depends sensitively on the network structure and a hypothetical treatment regime

Dynamic elasticity by the theory of characteristics

Method of characteristics for analysis of elastic wave equations in Cartesian coordinate

Test-retest reliability of structural brain networks from diffusion MRI

Structural brain networks constructed from diffusion MRI (dMRI) and tractography have been demonstrated in healthy volunteers and more recently in various disorders affecting brain connectivity. However, few studies have addressed the reproducibility of the resulting networks. We measured the test–retest properties of such networks by varying several factors affecting network construction using ten healthy volunteers who underwent a dMRI protocol at 1.5 T on two separate occasions. Each T1-weighted brain was parcellated into 84 regions-of-interest and network connections were identified using dMRI and two alternative tractography algorithms, two alternative seeding strategies, a white matter waypoint constraint and three alternative network weightings. In each case, four common graph-theoretic measures were obtained. Network properties were assessed both node-wise and per network in terms of the intraclass correlation coefficient (ICC) and by comparing within- and between-subject differences. Our findings suggest that test–retest performance was improved when: 1) seeding from white matter, rather than grey; and 2) using probabilistic tractography with a two-fibre model and sufficient streamlines, rather than deterministic tensor tractography. In terms of network weighting, a measure of streamline density produced better test–retest performance than tract-averaged diffusion anisotropy, although it remains unclear which is a more accurate representation of the underlying connectivity. For the best performing configuration, the global within-subject differences were between 3.2% and 11.9% with ICCs between 0.62 and 0.76. The mean nodal within-subject differences were between 5.2% and 24.2% with mean ICCs between 0.46 and 0.62. For 83.3% (70/84) of nodes, the within-subject differences were smaller than between-subject differences. Overall, these findings suggest that whilst current techniques produce networks capable of characterising the genuine between-subject differences in connectivity, future work must be undertaken to improve network reliability

Some clinical observations on trypanosomiasis rhodesiensis

1. The object of the paper is to record some clinical observations made during the study of 94 consecutive cases of Rhodesian Sleeping Sickness.2. The main factor in the epidemic spread was man-fly-man transmission. The occurrence of human cases with no history of contact and the high T.bracei infection rate among the local fauna are recorded, as the possibility of there being some reservoir cannot be excluded.3. The incubation period is probably between 1-3 weeks.4. The average duration of the illness is five months.5. There was an acute febrile onset in 24/£ of cases. Variations in the subsequent course are found and it is considered that these are due to the existence of strains of trypanosoines of different virulence.6. The central nervous system may be involved at a very early stage. This results in grave pathological changes, but the virulence of the infection is such that symptoms arising from its effect on the heart and other viscera predominate over those due to central nervous system involvement until the last few weeks of the illness. Cardiac symptoms are important and the essential lesion is a toxic myocarditis.7. The axillary group of glands are those most constantly enlarged.8. It is in cases which have relapsed after treatment that mental symptoms are most pronounced. In relapse a new strain of trynanosames has been created, of lowered virulence but resistant to the action of drugs.9. 'Bayer 205' has a strong and immediate effect oh infections of the peripheral blood but its action is not always permanent and it cannot penetrate into the deeper tissues. Tryparsamide is slower in action but it maintains a sterilization made by 'Bayer' and it can exert a beneficial action on the central nervous system.10. Treatment by * Bayer* should he followed immediately by Tryparasmide • A routine treatment by this method gives satisfactory results if treatment is started early in the course of the illness, hut even the most intensive and prolonged doses of the two drugs in combination cannot he relied upon to effect a cure if the disease is well established

Non-linear vortex dynamics and transient effects in ferromagnetic disks

We report a time resolved imaging and micromagnetic simulation study of the relaxation dynamics of a magnetic vortex in the non-linear regime. We use time-resolved photoemission electron microscopy and micromagnetic calculations to examine the emergence of non-linear vortex dynamics in patterned Ni80Fe20 disks in the limit of long field pulses. We show for core shifts beyond ~20-25% of the disk radius, the initial motion is characterized by distortions of the vortex, a transient cross-tie wall state, and instabilities in the core polarization that influence the core trajectories.Comment: 11 pages, 3 figures, submitted to Phys. Rev. Let

The Third Way for the Third Sector: Using Design to Transfer Knowledge and Improve Service in a Voluntary Community Sector Organisation

This paper describes a two-year Knowledge Transfer Partnership that concluded in September 2011. Knowledge Transfer Partnerships (KTP) is a UK-wide activity that helps organisations to improve their competitiveness and productivity by making better use of knowledge, technology and skills within universities, colleges and research organisations. This paper details the outcome of a KTP between Age UK Newcastle and Northumbria University’s School of Design that aimed to use Design approaches to improve the charity’s services. This paper will describe the recent context for organisations operating in the Voluntary Community Sector and discuss the relevance of a Design approach to both the improvement of customer services in this circumstance, as well as the transfer of knowledge to a capacity-starved organisation. It will also document how Design was used to achieve both of these aims, and the resulting impact of this engagement on the organisation and stakeholders

Mathematical Analysis and Simulations of the Neural Circuit for Locomotion in Lamprey

We analyze the dynamics of the neural circuit of the lamprey central pattern generator (CPG). This analysis provides insights into how neural interactions form oscillators and enable spontaneous oscillations in a network of damped oscillators, which were not apparent in previous simulations or abstract phase oscillator models. We also show how the different behaviour regimes (characterized by phase and amplitude relationships between oscillators) of forward/backward swimming, and turning, can be controlled using the neural connection strengths and external inputs.Comment: 4 pages, accepted for publication in Physical Review Letter

Costs of Collective Decisions, Choice of Tax Base, and Median Voter Equilibrium

This note examines the relationship between public expenditure growth and tax base elasticity in the context of the median voter model. If the revenue elasticity of the tax base and the median voter's income elasticity of demand for public services are not identical, the automatic increase in public revenue resulting from an increase in voter income will not match the median voter's increase in demand for public service expenditures. If adjusting tax rates is costly, the short-run rate of growth ofpublic expenditures will be biased in the direction of the automatic growth in tax revenue rather than being tied directly to changes in the median voter's demand for public services. The welfare loss occasioned by these positive decision-making costs can be reduced by choosing that tax base for which revenue elasticity most closely corresponds to income elasticity and also by evaluating tax rates in a multiperiod context at the time they are imposed.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Kinetic pathways of multi-phase surfactant systems

The relaxation following a temperature quench of two-phase (lamellar and sponge phase) and three-phase (lamellar, sponge and micellar phase) samples, has been studied in an SDS/octanol/brine system. In the three-phase case we have observed samples that are initially mainly sponge phase with lamellar and micellar phase on the top and bottom respectively. Upon decreasing temperature most of the volume of the sponge phase is replaced by lamellar phase. During the equilibriation we have observed three regimes of behaviour within the sponge phase: (i) disruption in the sponge texture, then (ii) after the sponge phase homogenises there is a lamellar nucleation regime and finally (iii) a bizarre plume connects the lamellar phase with the micellar phase. The relaxation of the two-phase sample proceeds instead in two stages. First lamellar drops nucleate in the sponge phase forming a onion `gel' structure. Over time the lamellar structure compacts while equilibriating into a two phase lamellar/sponge phase sample. We offer possible explanatioins for some of these observations in the context of a general theory for phase kinetics in systems with one fast and one slow variable.Comment: 1 textfile, 20 figures (jpg), to appear in PR