Electron heating at interplanetary shocks

Data for 41 forward interplanetary shocks show that the ratio of downstream to upstream electron temperatures. T sub e (d/u) is variable in the range between 1.0 (isothermal) and 3.0. On average, (T sub e (d/u) = 1.5 with a standard deviation, sigma e = 0.5. This ratio is less than the average ratio of proton temperatures across the same shocks, (T sub p (d/u)) = 3.3 with sigma p = 2.5 as well as the average ratio of electron temperatures across the Earth's bow shock. Individual samples of T sub e (d/u) and T sub p (d/u) appear to be weakly correlated with the number density ratio. However the amounts of electron and proton heating are well correlated with each other as well as with the bulk velocity difference across each shock. The stronger shocks appear to heat the protons more efficiently than they heat the electrons

Simultaneous measurements of magnetotail dynamics by IMP spacecraft

Changes in tail energy density during substorms in the magnetotail are given. In addition to plasma sheet thinnings seen prior to substorm onsets, a gradual decrease in plasma beta was detected in the deep tail which precedes onset and the more prominent plasma disappearance that typically accompanies it. The frequency of thinnings and the regions over which they occurred indicate that drastic changes in plasma sheet thickness are common features of substorms which occur at all locations across the tail

Autonomous vehicle interactions in the urban street environment: A research agenda

© ICE Publishing 2018. All rights reserved. The Venturer project is trialling an autonomous vehicle (AV) in the context of use on urban roads. This paper summarises a literature review undertaken to assist in developing a research agenda for the trialling. The first contribution of the paper is a framework of four use scenarios for AVs as follows: (1) fully segregated AV network, (2) motorway or expressway network, (3) typical urban network, (4) shared space. The paper then focuses on a review of the social interactions in the street environment and discusses issues concerning human behaviour in relation to autonomy. The second contribution of the paper is a set of research questions for AV trialling in relation to other road users, including, pedestrians and cyclists, which have emerged from the literature review.

Communication and marketing as tools to cultivate the public's health: a proposed "people and places" framework

<p>Abstract</p> <p>Background</p> <p>Communication and marketing are rapidly becoming recognized as core functions, or core competencies, in the field of public health. Although these disciplines have fostered considerable academic inquiry, a coherent sense of precisely how these disciplines can inform the practice of public health has been slower to emerge.</p> <p>Discussion</p> <p>In this article we propose a framework – based on contemporary ecological models of health – to explain how communication and marketing can be used to advance public health objectives. The framework identifies the attributes of people (as individuals, as social networks, and as communities or populations) and places that influence health behaviors and health. Communication, i.e., the provision of information, can be used in a variety of ways to foster beneficial change among both people (e.g., activating social support for smoking cessation among peers) and places (e.g., convincing city officials to ban smoking in public venues). Similarly, marketing, i.e., the development, distribution and promotion of products and services, can be used to foster beneficial change among both people (e.g., by making nicotine replacement therapy more accessible and affordable) and places (e.g., by providing city officials with model anti-tobacco legislation that can be adapted for use in their jurisdiction).</p> <p>Summary</p> <p>Public health agencies that use their communication and marketing resources effectively to support people in making healthful decisions and to foster health-promoting environments have considerable opportunity to advance the public's health, even within the constraints of their current resource base.</p

Solar parameters for modeling interplanetary background

The goal of the Fully Online Datacenter of Ultraviolet Emissions (FONDUE) Working Team of the International Space Science Institute in Bern, Switzerland, was to establish a common calibration of various UV and EUV heliospheric observations, both spectroscopic and photometric. Realization of this goal required an up-to-date model of spatial distribution of neutral interstellar hydrogen in the heliosphere, and to that end, a credible model of the radiation pressure and ionization processes was needed. This chapter describes the solar factors shaping the distribution of neutral interstellar H in the heliosphere. Presented are the solar Lyman-alpha flux and the solar Lyman-alpha resonant radiation pressure force acting on neutral H atoms in the heliosphere, solar EUV radiation and the photoionization of heliospheric hydrogen, and their evolution in time and the still hypothetical variation with heliolatitude. Further, solar wind and its evolution with solar activity is presented in the context of the charge exchange ionization of heliospheric hydrogen, and in the context of dynamic pressure variations. Also the electron ionization and its variation with time, heliolatitude, and solar distance is presented. After a review of all of those topics, we present an interim model of solar wind and the other solar factors based on up-to-date in situ and remote sensing observations of solar wind. Results of this effort will further be utilised to improve on the model of solar wind evolution, which will be an invaluable asset in all heliospheric measurements, including, among others, the observations of Energetic Neutral Atoms by the Interstellar Boundary Explorer (IBEX).Comment: Chapter 2 in the planned "Cross-Calibration of Past and Present Far UV Spectra of Solar System Objects and the Heliosphere", ISSI Scientific Report No 12, ed. R.M. Bonnet, E. Quemerais, M. Snow, Springe

Adolescent media use and its association to wellbeing in a Canadian national sample

Our objective is to describe associations between media usage and multiple wellbeing indicators in a nationally representative sample of Canadian youth (CSTADS 2012–13) enrolled in grades 7 to 12 (N = 41,057). Youth reported media usage (television/movie viewing, videogame playing, and surfing the internet), wellbeing (academic achievement, school connectedness, self-esteem, physical activity, intake of fruits and vegetables, and bullying), and psychological (drug use, drinking, and smoking) and sociodemographic confounds (ethnicity, grade, province, gender). Videogame playing was negatively associated with academic achievement, b = −0.07 (99% CI, −0.08–05), physical activity, b = −3.09, (99% CI, −3.63–2.56), school connectedness, b = −0.03 (99% CI, −0.04–0.02), self-esteem, b = −0.13 (99% CI, −0.16–0.09), and the consumption of fruits and vegetables b = −0.07 (99% CI, −0.11–0.03). Internet usage was negatively related to self-esteem, b = −0.25 (99% CI, −0.28–0.21), school connectedness, b = −0.03 (99% CI, −0.03–0.02), academic achievement, b = −0.02 (99% CI, −0.03–0.002) and physical activity b = −1.42 (99% CI, −1.92–0.91). Finally, television exposure was linked with less fruits and vegetable consumption, b = −0.09 (99% CI, −0.12–0.06), academic achievement b = −0.05 (99% CI, −0.07–0.04), school connectedness b = −0.02 (99% CI, −0.03–0.01), self-esteem b = −0.06 (99% CI, −0.11–0.003), and physical activity b = −1.09 (99% CI, −1.64–0.54). Internet, television/movies, and videogame time also increased the odds of bullying others by 9%, OR = 1.09 (99% CI, 1.04–1.14) 8%, OR = 1.08 (99% CI, 1.01–1.16) and 7%, OR = 1.07 (99% CI, 1.01–1.14) respectively. Overall effect sizes were small yet may represent significant impairment for heavy media users. Keywords: Media usage, Academic achievement, School connectedness, Physical activity, Self-esteem, Bullying, Fruits and vegetables, Wellbeing, Yout

Adolescent media use and its association to wellbeing in a Canadian national sample

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Mangrove response to environmental changes predicted under varying climates: Case studies from Australia

Over the past few decades, many of the world’s mangrove forests have experienced significant change, which can be attributed to human activities and also natural causes. However, a component may also be due to factors that are commonly associated with anthropogenic climate change including higher air temperatures, variations in rainfall, increases in storm frequencies and intensities, and rising sea levels. The expected responses of mangrove to these drivers include changes in extent (latitudinal, seaward and landward), growth rates and productivity, and species composition. This paper reviews such responses and then, using examples from Australia, illustrates how these might appear within and be detected using single-date or time-series of remote sensing data acquired in different modes (e.g., aerial photography, optical and radar). In doing so, it informs countries and organisations of the potential impacts of climate change on mangrove forests and how these may be monitored using remote sensing data