Food waste interventions: Experimental evidence of the effectiveness of environmental messages

Given the need to reduce food waste, information-based intervention campaigns that present messages to individuals are crucial and likely part of the solution. However, the subject matter of these messages has been under scholarly debate. Although empirical evidence is lacking, scholars and practitioners have recently focused on environmental messages even though, traditionally, others have advocated for taste- or financially-oriented messages. With two experiments, totaling 1,656 participants, we contribute to the resolution of this debate. We examined how environmental and taste-oriented messages affect behavioral intentions to reduce food waste and to plan meals (Experiment 1) and how environmental and financially-oriented messages affect interest in food waste reduction efforts (Experiment 2). In Experiment 1, we found that a message linking meal planning to tackling climate change elicited more future meal planning intentions and more general intentions to reduce food waste than the control condition. We also found that an environmental message was more effective in increasing general intentions to reduce food waste and as effective in increasing future meal planning intentions, than a message that linked meal planning to tasty food. In Experiment 2, we found that an environmental message promoted more interest in food waste reduction efforts than no message and was as effective as a message that conveyed the financial burden of food waste. We discuss implications for future intervention campaigns and research

Don't Put All Your Eggs in One Basket: Testing An Integrative Model of Household Food Waste

Scholarly investigations into household food waste have advanced our knowledge of its determinants by focusing on food management behaviors (FMB) and by using the theory of planned behavior (TPB). Drawing on literature from environmental psychology, we created and tested a comprehensive framework that not only encompasses TPB and FMB, but also individual goals and values, which, we argue, can advance understanding of why people waste food. Using a two-wave survey design with a quasi-representative sample of the UK population (N = 1,336 participants), we tested our framework with Structural Equation Modelling (SEM). Broadly, results indicated support for our framework in that individual values were associated with short-term cognitions and participants’ goals, particularly the goal to behave responsibly, which were in turn associated with FMB and intentions; these, finally, were associated with self-reported food waste. Overall, our results indicate that food waste is the result of different cognitive and behavioral processes

Neighbour identity hardly affects litter-mixture effects on decomposition rates of New Zealand forest species.

The mass loss of litter mixtures is often different than expected based on the mass loss of the component species. We investigated if the identity of neighbour species affects these litter-mixing effects. To achieve this, we compared decomposition rates in monoculture and in all possible two-species combinations of eight tree species, widely differing in litter chemistry, set out in two contrasting New Zealand forest types. Litter from the mixed-species litter bags was separated into its component species, which allowed us to quantify the importance of litter-mixing effects and neighbour identity, relative to the effects of species identity, litter chemistry and litter incubation environment. Controlling factors on litter decomposition rate decreased in importance in the order: species identity (litter quality) >> forest type >> neighbour species. Species identity had the strongest influence on decomposition rate. Interspecific differences in initial litter lignin concentration explained a large proportion of the interspecific differences in litter decomposition rate. Litter mass loss was higher and litter-mixture effects were stronger on the younger, more fertile alluvial soils than on the older, less-fertile marine terrace soils. Litter-mixture effects only shifted percentage mass loss within the range of 1.5%. There was no evidence that certain litter mixtures consistently showed interactive effects. Contrary to common theory, adding a relatively fast-decomposing species generally slowed down the decomposition of the slower decomposing species in the mixture. This study shows that: (1) species identity, litter chemistry and forest type are quantitatively the most important drivers of litter decomposition in a New Zealand rain forest; (2) litter-mixture effects—although statistically significant—are far less important and hardly depend on the identity and the chemical characteristics of the neighbour species; (3) additive effects predominate in this ecosystem, so that mass dynamics of the mixtures can be predicted from the monocultures

Grain refinement of Al-Si hypoeutectic alloys by Al3Ti1B master alloy and ultrasonic treatment

Al-Si alloys are widely used in automotive and aerospace industries due to their excellent castability, high strength to weight ratio and good corrosion resistance. However, Si poisoning severely limits the degree of grain refinement with the grain size becoming larger as the Si content increases. Generally the effect of Si poisoning is reduced by increasing the amount of master alloy added to the melt during casting. However, an alternative approach is physical grain refinement through the application of an external force (e.g. mechanical or electromagnetic stirring, intensive shearing and ultrasonic irradiation). This work compares the grain refining efficiency of three approaches to the grain refinement of a range of hypoeutectic Al-Si alloys by (i) the addition of Al3Ti1B master alloy, (ii) the application of Ultrasonic Treatment (UT) and (iii) the combined addition of A13Ti1B master alloy and the application of UT

A global experiment on motivating social distancing during the COVID-19 pandemic

Significance Communicating in ways that motivate engagement in social distancing remains a critical global public health priority during the COVID-19 pandemic. This study tested motivational qualities of messages about social distancing (those that promoted choice and agency vs. those that were forceful and shaming) in 25,718 people in 89 countries. The autonomy-supportive message decreased feelings of defying social distancing recommendations relative to the controlling message, and the controlling message increased controlled motivation, a less effective form of motivation, relative to no message. Message type did not impact intentions to socially distance, but people’s existing motivations were related to intentions. Findings were generalizable across a geographically diverse sample and may inform public health communication strategies in this and future global health emergencies. Abstract Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges

Influence of ultrasonic melt treatment on the formation of primary intermetallics and related grain refinement in aluminum alloys

Ultrasonic melt treatment (UST) is known to induce grain refining in aluminum alloys. Previous studies have clearly shown that in Al–Zr–Ti alloys, the primary Al3Zr intermetallics were dramatically refined by cavitation-assisted fragmentation, and a good refinement effect was achieved. In this article, Al–Ti, Al–Ti–Zr alloys, and some commercial aluminum alloys are used to analyze the effect of UST on primary intermetallics and grain refinement. The addition of a small amount of Al–3Ti–B master alloy is also studied in order to compare with the addition of Ti and Zr in commercial aluminum alloys. Experimental results show that the ultrasonic grain refining effect is not only related to the size of particles which are refined and/or dispersed by UST, but also related to an undercooling available for activation of these particles in the solidification process. Athermal heterogeneous nucleation theory is considered to explain the effect of size and distribution of substrate particles on the grain structure with different undercoolings. The distribution of primary particle sizes results in the distribution of required undercoolings. Grain refining occurs when the undercooling is large enough to activate the refined primary intermetallics or dispersed inoculants.Materials Science and EngineeringMechanical, Maritime and Materials Engineerin