What Dogs Know

My dog understands me! At least, many dog owners think so. New scientific studies actually show that dogs understand a lot about us humans. For example, they can figure out what humans can and cannot see. Some dogs can even distinguish large numbers of toys by name, like Rico, the internationally famous Border collie. But do dogs also understand our emotions? Can they grasp cause and effect relationships? What fascinates us humans about dogs? Is it only the proverbial ‘puppy dog eyes’ that make dogs look sympathetic? Or is it the fact that these animals have grown very well-attuned to humans and are willing to cooperate with them? In a total of ten chapters, Juliane Bräuer and Juliane Kaminski present the results of the most important scientific studies of the last twenty years on dog cognition.1 Why Dogs? --- p. 1 2 How Wolves Became Dogs --- p. 11 3 Dogs Are Not Wolves --- p. 27 4 What Do Dogs Understand About Others? --- p. 45 5 Do Dogs Learn by Observing Others? --- p. 61 6 How Do Dogs Interpret Human Gestures? --- p. 79 7 Communication Between Dogs and Humans --- p. 95 8 What Do Dogs Know About Their Environment? --- p. 119 9 When Dogs Help --- p. 143 10 Looking Ahead --- p. 15

The dissonance between knowing animals are sentient beings yet eating them: Commentary on Rowan et al. on Sentience Politics

Animal sentience is linked to the bigger picture of climate and health crises and “carnism” is a factor in the dissonance among (1) knowing animals are sentient, (2) caring about their feelings, and (3) not acting accordingly. We discuss our responsibility as researchers and as individual human beings.1. Crises of our time 2. Individual responsibility 3. “Carnism”: an unconscious belief system 4. What can we as researchers do about it

Dogs display owner-specific expectations based on olfaction

Most current knowledge about dogs’ understanding of, and reacting to, their environment is limited to the visual or auditory modality, but it remains unclear how olfaction and cognition are linked together. Here we investigate how domestic dogs search for their owners using their excellent olfactory sense. We raise the question whether dogs have a representation of someone when they smell their track. The question is what they expect when they follow a trail or whether they perceive an odour as a relevant or non-relevant stimulus. We adopted a classical violation-of-expectation paradigm—and as targets we used two persons that were both important to the dog, usually the owners. In the critical condition subjects could track the odour trail of one target, but at the end of the trail they find another target. Dogs showed an increased activity when the person did not correspond with the trail compared to a control condition. Moreover, we found huge individual differences in searching behaviour supporting the assumption that dogs are only able to smell when they really sniff, and that the temperature has an influence on dogs performance. Results are discussed in the light of how cognitive abilities, motivation and odour perception influence each other.Methods - Subjects. - Setup. - Procedure. - Design. - Coding and analysis. Results Discussio

Effect of shared information and owner behavior on showing in dogs (Canis familiaris)

Dogs’ production of referential communicative signals, i.e., showing, has gained increasing scientific interest over the last years. In this paper, we investigate whether shared information about the present and the past affects success and form of dog–human interactions. Second, in the context of showing, owners have always been treated as passive receivers of the dog’s signals. Therefore, we examined whether the owner’s behavior can influence the success and form of their dog’s showing behavior. To address these questions, we employed a hidden-object task with knowledgeable dogs and naïve owners. Shared information about the present was varied via the spatial set-up, i.e., position of hiding places, within dog–owner pairs, with two conditions requiring either high or low precision in indicating the target location. Order of conditions varied between pairs, representing differences in shared knowledge about the past (communication history). Results do not support an effect of communication history on either success or showing effort. In contrast, the spatial set-up was found to affect success and choice of showing strategies. However, dogs did not adjust their showing effort according to different spatial set-ups. Our results suggest that the latter could be due to the owner’s influence. Owner behavior generally increased the effort of their dog’s showing behavior which was stronger in the set-up requiring low showing precision. Moreover, our results suggest that owners could influence their dog’s showing accuracy (and thereby success) which, however, tended to be obstructive.Introduction Showing Shared information and the principle of least effort The present study Materials and methods subjects materials and set-up prodedure; pretest test design behavioral coding statistical analysis) Results overall success distribution of showing types effect of correct showing, condition and time on success effect of condition and time on showing effort correlation between showing accuracy and seconds effect of owner behavior on correct showing effect of owner behavior on showing effort) Discussion Communication about the hidden object’s location Sensitivity to spatial set‑up and communication history The principle of least effort and the owner’s influence on it Limitations and implications for future researc

Dogs distinguish human intentional and unintentional action

When dogs interact with humans, they often show appropriate reactions to human intentional action. But it is unclear from these everyday observations whether the dogs simply respond to the action outcomes or whether they are able to discriminate between different categories of actions. Are dogs able to distinguish intentional human actions from unintentional ones, even when the action outcomes are the same? We tested dogs’ ability to discriminate these action categories by adapting the so-called “Unwilling vs. Unable” paradigm. This paradigm compares subjects’ reactions to intentional and unintentional human behaviour. All dogs received three conditions: In the unwilling-condition, an experimenter intentionally withheld a reward from them. In the two unable-conditions, she unintentionally withheld the reward, either because she was clumsy or because she was physically prevented from giving the reward to the dog. Dogs clearly distinguished in their spontaneous behaviour between unwilling- and unable-conditions. This indicates that dogs indeed distinguish intentional actions from unintentional behaviour. We critically discuss our findings with regard to dogs’ understanding of human intentional action.Results - Analysis of waiting - Other behavioural reactions Discussion Methods - Ethical statement - Subjects - Experimental set‑up - Procedure - Codin

Entropies of algebraic Z d -actions and K-theory

Eine algebraische Z-d-Aktion ist eine kompakte abelsche Gruppe X, auf der die Gruppe Z d, d.h. das d-fache direkte Produkt der ganzen Zahlen, mittels stetigen Gruppenautomorphismen operiert. Die Entropie einer algebraischen Z-d-Aktion ist eine reelle Zahl, die man als Maß der Unordnung des Systems interpretieren kann. Gewissen Z-d-Aktionen kann man auch eine p-adische Zahl, die sogenannte p-adische Entropie, zuweisen. In der vorliegenden Arbeit definieren wir p-adische Entropie für eine größere Klasse von algebraischen Z-d-Aktionen. Dazu führen wir die Eigenschaft der p-adischen Expansität ein. Dann benutzen wir algebraische K-Theorie sowie die p-adische Fuglede-Kadison-Determinante, um unsere allgemeinere Version der p-adischen Entropie zu gewinnen. Dieser Ansatz liefert auch für die Theorie der expansiven Z-d-Aktionen neue Erkenntnisse, beispielsweise eine neue Invariante, die hier auf Ebene der K-Theorie beschrieben wird

Assessment of optical CT as a future QA tool for synchrotron x-ray microbeam therapy.

Synchrotron microbeam radiation therapy (MRT) is an advanced form of radiotherapy for which it is extremely difficult to provide adequate quality assurance. This may delay or limit its clinical uptake, particularly in the paediatric patient populations for whom it could be especially suitable. This study investigates the extent to which new developments in 3D dosimetry using optical computed tomography (CT) can visualise MRT dose distributions, and assesses what further developments are necessary before fully quantitative 3D measurements can be achieved. Two experiments are reported. In the first cylindrical samples of the radiochromic polymer PRESAGE(®) were irradiated with different complex MRT geometries including multiport treatments of collimated 'pencil' beams, interlaced microplanar arrays and a multiport treatment using an anthropomorphic head phantom. Samples were scanned using transmission optical CT. In the second experiment, optical CT measurements of the biologically important peak-to-valley dose ratio (PVDR) were compared with expected values from Monte Carlo simulations. The depth-of-field (DOF) of the optical CT system was characterised using a knife-edge method and the possibility of spatial resolution improvement through deconvolution of a measured point spread function (PSF) was investigated. 3D datasets from the first experiment revealed excellent visualisation of the 50 μm beams and various discrepancies from the planned delivery dose were found. The optical CT PVDR measurements were found to be consistently 30% of the expected Monte Carlo values and deconvolution of the microbeam profiles was found to lead to increased noise. The reason for the underestimation of the PVDR by optical CT was attributed to lack of spatial resolution, supported by the results of the DOF characterisation. Solutions are suggested for the outstanding challenges and the data are shown already to be useful in identifying potential treatment anomalies

Process for the modification of polymers, in particular polymer nanoparticles

The present invention relates to a highly efficient and ultra fast process for the photo-initiated preparation of polymers by polymerization using photoinitiators comprising a phosphorous oxide or -sulfide group and modification of said polymers. In particular the invention relates to an ultra fast process for the photo-initiated preparation of latices comprising polymer nanoparticles by heterophase polymerization using photoinitiators comprising a phosphorous oxide or -sulfide group and their modification. In another aspect, the invention relates to polymers and polymer nanoparticles obtainable by said process

Molecular traffic control in single-file networks with fast catalysts

As a model for molecular traffic control (MTC) we investigate the diffusion of hard core particles in crossed single-file systems. We consider a square lattice of single-files being connected to external reservoirs. The (vertical) alpha-channels, carrying only A-particles, are connected to reservoirs with constant density ra. B-particles move along the (horizontal) beta-channels, which are connected to reservoirs of density rB. We allow the irreversible transition A to B at intersections. We are interested in the stationary density profile in the alpha- and beta- channels, which is the distribution of the occupation probabilities over the lattice. We calculate the stationary currents of the system and show that for sufficiently long channels the currents (as a function of the reservoir densities) show in the limit of large transition rates non analytic behavior. The results obtained by direct solution of the master equation are verified by kinetic Monte Carlo simulations.Comment: 11 page