Dark Field Differential Dynamic Microscopy enables the accurate characterization of the roto-translational dynamics of bacteria and colloidal clusters

Micro- and nanoscale objects with anisotropic shape are key components of a variety of biological systems and inert complex materials, and represent fundamental building blocks of novel self-assembly strategies. The time scale of their thermal motion is set by their translational and rotational diffusion coefficients, whose measurement may become difficult for relatively large particles with small optical contrast. Here we show that Dark Field Differential Dynamic Microscopy is the ideal tool for probing the roto-translational Brownian motion of shape anisotropic particles. We demonstrate our approach by successful application to aqueous dispersions of non-motile bacteria and of colloidal aggregates of spherical particles

Farming’s Future Depends on Continued Innovation

Farming is on the upswing in Maine, with many innovative practices and institutions described in this article

Conversion as a Mechanism of Hybridization: The Institutional Transfer of Industrial Relations and Vocational Training from Western to Eastern Germany

Looking back over the two decades since German unification, the main questions I want to answer are to what extent and through what mechanisms the transfer of the system of industrial relations and vocational training - two cornerstones of the West German model - has occurred in eastern Germany. The literature argues that institutional transfer very often leads to a process of hybridization in institutions. However, the concept of hybridization has also been criticized as being mainly descriptive and vague about the actual mechanisms of hybridization. In this paper I argue that these mechanisms should be specified further and suggest that the hybridization approach can be fruitfully linked to recent theories of institutional change. As far as the transfer of industrial relations and vocational training from western to eastern Germany is concerned, I argue in particular that hybridization has mainly occurred through what institutional literature has recently defined as the mechanism of conversion

Farms and the Working Landscape

After years of losing farms and farmers, Maine is seeing an increase in the number of acres being farmed, due partly to a resurgence of interest in farming and new tools that help preserve working landscapes. These tools include agricul­tural easements such as those offered by the Land for Maine’s Future, the Buy/Protect/Sell program at Maine Farmland Trust, local ordinances, and several federal program

If You Want To See Me You\u27ve Got To Come To-Day

https://digitalcommons.library.umaine.edu/mmb-vp/4620/thumbnail.jp

Positive emotions and quality of life in dogs

Positive affect is fundamental to ensuring good animal welfare. Discrete and dimensional theories of emotion have recently been used to explore the relation between cognition and affect and to develop cognitive measures of positive affect. Human quality-of-life assessment focuses on positive affect, which is difficult to measure objectively in dogs. Expanding on Kujala’s (2017) discussion of positive emotions and cognitive measures of affect, I suggest how these are relevant to assessing canine quality of life

Current trends in dog-human communication:do dogs inform?

Domestic dogs are especially skillful at understanding human forms of communication. Evidence suggests that dogs\u2019 skills in this domain might be an adaptation to life with humans and the result of selection processes during domestication. One question that has sparked a lot of research in recent years is to what extent dogs\u2019 communication is in any way comparable to that of human infants. Here, we discuss recent research that has examined the extent to which dogs communicate to inform others. Communication with the motive to inform others is, as of yet, seen as a unique feature of human communication

Do dogs provide information helpfully?

Dogs are particularly skilful during communicative interactions with humans. Dogs' abilities to use human communicative cues in cooperative contexts outcompete those of other species, and might be the result of selection pressures during domestication. Dogs also produce signals to direct the attention of humans towards outside entities, a behaviour often referred to as showing behaviour. This showing behaviour in dogs is thought to be something dogs use intentionally and referentially. However, there is currently no evidence that dogs communicate helpfully, i.e. to inform an ignorant human about a target that is of interest to the human but not to the dog. Communicating with a helpful motive is particularly interesting because it might suggest that dogs understand the human's goals and need for information. In study 1, we assessed whether dogs would abandon an object that they find interesting in favour of an object useful for their human partner, a random novel distractor, or an empty container. Results showed that it was mainly self-interest that was driving the dogs' behaviour. The dogs mainly directed their behaviour towards the object they had an interest in, but dogs were more persistent when showing the object relevant to the human, suggesting that to some extent they took the humans interest into account. Another possibility is that dogs' behaviour was driven by an egocentric motivation to interact with novel targets and that the dogs' neophila might have masked their helpful tendencies. Therefore, in study 2 the dogs had initial access to both objects, and were expected to indicate only one (relevant or distractor). The human partner interacted with the dog using vocal communication in half of the trials, and remaining silent in the other half. Dogs from both experimental groups, i.e. indicating the relevant object or indicating the distractor, established joint attention with the human. However, the human's vocal communication and the presence of the object relevant to the human increased the persistency of showing, supporting the hypothesis that the dogs understood the objects' relevance to the human. We propose two non-exclusive explanations. These results might suggest that informative motives could possibly underlie dogs' showing. It is also possible that dogs might have indicated the location of the hidden object because they recognised it as the target of the human's search. This would be consistent with taking into account the objects' relevance, without necessarily implying that the dogs understood the human's state of knowledge