Comment on `Magic strains in face-centered and body-centered cubic lattices'

The six symmetry-related so-called magic strain tensors that transform a f.c.c. lattice (or a b.c.c. lattice) into itself, which have been reported recently by Boyer [Acta Cryst. (1989), A45, FC29-FC32] are not unique: an infinite number of displacement tensors can be constructed that transform one lattice into another, or into itself. There is no connection with fivefold symmetry, other than that in any f.c.c. crystal

On the origin of second-peak splitting in the static structure factor of metallic glasses

It is proposed that the splitting of the second peak of the total static structure factor, S(k), of many metallic glasses is essentially the same feature as the indentation at kσ = (9/2)π in the function (sin k σ + α−1 sin kασ), caused by the coincidence of the fourth minimum of the second term with the third maximum of the first term when α ≈ 5/3. Together with the strong-weak relation of the split peak components of S(k), this feature indicates the splitting to be direct evidence for face-sharing of regular tetrahedra (α = 2√2/3) dominating the topological short range order; increasing the number of face-sharing tetrahedra in local structural units indeed increases the amount of peak splitting in S(k); a dense random packing of well defined identical structural units (DRPSU), with neighbouring units linked together by a shared icosahedron, is described in detail. The packing fraction in a homogeneous, isotropic 1078-atom model is 0.67, after static relaxation under a two-body Lennard-Jones potential.\ud \u

Naar een analytische stratificatiesociologie. Over klasse, status en ongelijkheid

Een van de hoofdvragen van de sociologie richt zich op de oorzaken en gevolgen van maatschappelijke ongelijkheden. Wij betogen dat de sociologie vanwege twee samenhangende problemen tekortschiet in de beantwoording van die vraag. Ten eerste wordt het door Weber uitgewerkte verschil tussen stratificatie in het economische domein (‘klasse’) en stratificatie in het culturele domein (‘status’) veronachtzaamd. Ten tweede richt stratificatieonderzoek zich voornamelijk op het bieden van statistische in plaats van theoretische verklaringen. Daardoor maakt onderzoek niet goed duidelijk of en hoe klassenverschillen en statusverschillen leiden tot 1) ongelijkheid in het economische domein, 2) intergenerationele reproductie van stratificatie, en 3) verschillende denk- voel- en handelingsrepertoires. Om deze problemen op te lossen werken we een alternatieve analytisch-sociologische onderzoeksaanpak uit. We illustreren de waarde van deze aanpak door uitkomsten van bestaande stratificatiestudies kritisch te bespreken. Het artikel sluit af met de implicaties van de hier gepropageerde analytische stratificatiesociologie voor vervolgonderzoek

Ingroup-Outgroup Bias in Contagious Yawning by Chimpanzees Supports Link to Empathy

Humans favor others seen as similar to themselves (ingroup) over people seen as different (outgroup), even without explicitly stated bias. Ingroup-outgroup bias extends to involuntary responses, such as empathy for pain. However, empathy biases have not been tested in our close primate relatives. Contagious yawning has been theoretically and empirically linked to empathy. If empathy underlies contagious yawning, we predict that subjects should show an ingroup-outgroup bias by yawning more in response to watching ingroup members yawn than outgroup. Twenty-three chimpanzees (Pan troglodytes) from two separate groups watched videos of familiar and unfamiliar individuals yawning or at rest (control). The chimpanzees yawned more when watching the familiar yawns than the familiar control or the unfamiliar yawns, demonstrating an ingroup-outgroup bias in contagious yawning. These results provide further empirical support that contagious yawning is a measure of empathy, which may be useful for evolutionary biology and mental health

Moreel conservatisme en autoritarisme theoretisch en methodisch ontward

This article demonstrates that studies in political sociology are flawed, because they fail to distinguish between moral conservatism/progressiveness and authoritarianism/libertarianism. Such a distincti

Weerstand tegen vrijhandel: niet economisch, maar cultureel

Bezwaren tegen vrijhandelsverdragen komen niet voort uit een zwakke economische positie van laagopgeleiden, maar uit een verschil in cultureel kapitaal. Herverdeling van de economische vruchten van vrijhandel zal het enthousiasme voor een verdrag als TTIP daarom niet vergroten

Toshisada Nishida (1941–2011): Chimpanzee Rapport

Frans de Waal pays tribute to pioneering primatologist Toshisada Nishida, who transformed our understanding of chimpanzee behavior and culture and galvanized efforts to ensure their conservation

Populism and Support for Protectionism: The Relevance of Opposition to Trade Openness for Leftist and Rightist Populist Voting in The Netherlands

Leftist and rightist populist parties in Western Europe both oppose trade openness. Is support for economic protectionism also relevant for their electorates? We assess this in the Netherlands, where both types of populist parties have seats in parliament. Analyses of representative survey data (n = 1,296) demonstrate that support for protectionism drives voting for such parties, as do the well-established determinants of political distrust (both populist constituencies), economic egalitarianism (leftist populist constituency) and ethnocentrism (rightist populist constituency). Surprisingly, support for protectionism does not mediate the relationship between economic egalitarianism and voting for left-wing populists, or the link between political distrust and voting for either left-wing or right-wing populist parties. In contrast, support for protectionism partly mediates the association between ethnocentrism and voting for right-wing populists. We discuss the largely independent role of protectionism in populist voting in relation to the cultural cleavage in politics and electoral competition, and also provide suggestions for future research

Vibrations of closed-shell Lennard-Jones icosahedral and cuboctahedral clusters and their effect on the cluster ground state energy

Vibrational spectra of closed shell Lennard-Jones icosahedral and cuboctahedral clusters are calculated for shell numbers between 2 and 9. Evolution of the vibrational density of states with the cluster shell number is examined and differences between icosahedral and cuboctahedral clusters described. This enabled a quantum calculation of quantum ground state energies of the clusters in the quasiharmonic approximation and a comparison of the differences between the two types of clusters. It is demonstrated that in the quantum treatment, the closed shell icosahedral clusters binding energies differ from those of cuboctahedral clusters more than is the case in classical treatment