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Oxidative treatment of seawater in coastal and shipboard installations is applied to control biofouling and/or minimize the input of noxious or invasive species into the marine environment. This treatment allows a safe and efficient operation of industrial installations and helps to protect human health from infectious diseases and to maintain the biodiversity in the marine environment. On the downside, the application of chemical oxidants generates undesired organic compounds, so-called disinfection by-products (DBPs), which are discharged into the marine environment. This article provides an overview on sources and quantities of DBP inputs, which could serve as basis for hazard analysis for the marine environment, human health and the atmosphere. During oxidation of marine water, mainly brominated DBPs are generated with bromoform (CHBr 3 ) being the major DBP. CHBr 3 has been used as an indicator to compare inputs from different sources. Total global annual volumes of treated seawater inputs resulting from cooling processes of coastal power stations, from desalination plants and from ballast water treatment in ships are estimated to be 470-800 × 10 9  m 3 , 46 × 10 9  m 3 and 3.5 × 10 9  m 3 , respectively. Overall, the total estimated anthropogenic bromoform production and discharge adds up to 13.5-21.8 × 10 6  kg/a (kg per year) with contributions of 11.8-20.1 × 10 6  kg/a from cooling water treatment, 0.89 × 10 6  kg/a from desalination and 0.86 × 10 6  kg/a from ballast water treatment. This equals approximately 2-6% of the natural bromoform emissions from marine water, which is estimated to be 385-870 × 10 6  kg/a., (Copyright © 2022. Published by Elsevier Ltd.)

The present study examined whether there are distinct groups of children with reactive versus proactive motives for their aggressive behavior. We extended previous research by using a person-based analytical approach on data from a questionnaire assessing children's motives independently from the severity of their aggression. Two competing hypotheses were tested. The both subtypes hypothesis holds that both reactive and proactive subtypes exist, as well as a mixed subtype. The reactive only hypothesis holds that only reactive and mixed subtypes exist. Hypotheses were tested on existing data from a community sample of children displaying aggression (Study 1: n = 228, ages 10-13, 54% boys), and two clinical samples of children with aggressive behavior problems (Study 2: n = 115, ages 8-13, 100% boys; Study 3: n = 123, ages 6-8, 78% boys). Teachers reported on children's reactive and proactive motives. We selected measures available from peers, parents, teachers, and children themselves to compare the supported subtypes on variables that previous literature suggests uniquely correlate with reactive versus proactive aggression. Confirmatory latent profile analyses revealed that the both subtypes hypothesis best fit the data of all three samples. Most children were classified as reactive (55.7-61.8% across samples), with smaller percentages classified as proactive (10.4-24.1%) and mixed (18.0-33.9%). However, these subtypes only differed in expected directions on 7 out of 34 measures. Overall, results support the existence of both reactive and proactive subtypes of aggressive children, but the distinctiveness of these subtypes in terms of social-emotional characteristics warrants further study., (© 2021. The Author(s).)

Two-dimensional Particle Tracking Velocimetry (PTV) is a promising technique to study the behaviour of granular flows. The aim is to experimentally determine the free surface width and position of the shear band from the velocity profile to validate simulations in a split-bottom shear cell geometry. The position and velocities of scattered tracer particles are tracked as they move with the bulk flow by analyzing images. We then use a new technique to extract the continuum velocity field, applying coarse-graining with the postprocessing toolbox MercuryCG on the discrete experimental PTV data. For intermediate filling heights, the dependence of the shear (or angular) velocity on the radial coordinate at the free surface is well fitted by an error function. From the error function, we get the width and the centre position of the shear band. We investigate the dependence of these shear band properties on filling height and rotation frequencies of the shear cell for dry glass beads for rough and smooth wall surfaces. For rough surfaces, the data agrees with the existing experimental results and theoretical scaling predictions. For smooth surfaces, particle-wall slippage is significant and the data deviates from the predictions. We further study the effect of cohesion on the shear band properties by using small amount of silicon oil and glycerol as interstitial liquids with the glass beads. While silicon oil does not lead to big changes, glycerol changes the shear band properties considerably. The shear band gets wider and is situated further inward with increasing liquid saturation, due to the correspondingly increasing trend of particles to stick together.

The well-known distinction between reactive and proactive aggression is theoretically important but empirically controversial. Recently, aggression researchers have argued that we should separate the form and function of aggression to make a clearer distinction between reactive and proactive aggression. This article describes the validation of a new teacher-report Instrument for Reactive and Proactive Aggression (IRPA) that assesses the form separate from the function of aggression. We demonstrated good discriminant, convergent, and construct validity of the IRPA in a sample of 427 children aged 10 to 13. Reactive and proactive functions of aggression were independent constructs (r = 0.03) which indicates excellent discriminant validity. Convergent validity was satisfactory; scores from the IRPA were moderately to highly related to scores from the widely used Teacher Rating Instrument, TRI (Dodge and Coie in Journal of Personality and Social Psychology 53:1146-1158, 1987). Additionally, reactive and proactive aggression showed unique correlations with most a priori hypothesized theoretically relevant variables, which indicates construct validity. (150 words).

There is great concern about the effects of playing violent video games on aggressive behavior. The present experimental study was aimed at investigating the differential effects of actively playing vs. passively watching the same violent video game on subsequent aggressive behavior. Fifty-seven children aged 10-13 either played a violent video game (active violent condition), watched the same violent video game (passive violent condition), or played a non-violent video game (active non-violent condition). Aggression was measured through peer nominations of real-life aggressive incidents during a free play session at school. After the active participation of actually playing the violent video game, boys behaved more aggressively than did the boys in the passive game condition. For girls, game condition was not related to aggression. These findings indicate that, specifically for boys, playing a violent video game should lead to more aggression than watching television violence., (Copyright 2007 Wiley-Liss, Inc.)

The present meta-analytic review aimed to clarify divergent findings concerning the relation between reactive and proactive aggression in children and adolescents. Fifty-one studies with 17,965 participants were included in the analysis. A significant correlation between reactive and proactive aggression was found. The strength of this relation varied considerably between studies, from -.10 to .89. Observational assessment and tilt/noise tasks were associated with smaller correlations than questionnaires. Within the large group of questionnaire studies, studies disentangling the form and function of aggression found lower correlations than studies that did not disentangle form and function. Among questionnaire studies, higher reliability was associated with larger correlations. Effect size did not depend on other study characteristics such as sample type, age, and informant type. It is concluded that reactive and proactive aggression are most clearly distinguished with behavioral observations and questionnaires that unravel form and functions of aggression.