Catalytic hydrogenation of carboxylic acid esters, amides, and nitriles with homogeneous catalysts

This review describes the catalytic reduction of amides, carboxylic acid esters and nitriles with homogeneous catalysts using molecular hydrogen as an environmental friendly reducing agent

Dicyclohexylbis(naphthalen-1-ylmethyl)phosphonium chloride chloroform disolvate

In the title solvated phosphonium salt, C34H40P+·Cl -·2CHCl3, the two cyclohexyl and two 1-naphthylmethyl groups at the P atom are in a distorted tetrahedral arrangement [105.26 (6)-113.35 (6)°]. Both cyclohexyl rings adopt a chair conformation. The dihedral angle between the naphthyl ring systems is 74.08 (3)°

Editors' Review and Introduction:The Cultural Evolution of Cognition

This topic addresses a question of key interest to cognitive science, namely which factors may have triggered, constrained, or shaped the course of cognitive evolution. It highlights the relevance of culture as a driving force in this process, with a special focus on social learning and language, conceptual tools, and material culture. In so doing, the topic combines two goals: to provide an overview of current empirical and theoretical work leading this field, tailored for a wider cognitive science audience, and to investigate the potential for integrating multiple perspectives across several timescales and levels of analysis, from the microlevel of individual behavior to the macrolevel of cultural change and language diversification. One key purpose is to assess the extent to which the different research approaches can cross‐fertilize each other, thereby also contributing to the advancement of cognitive science more broadly.acceptedVersio

Monodisperse nickel-nanoparticles for stereo- and chemoselective hydrogenation of alkynes to alkenes

Here, we report the use of monosaccharides for the preparation of novel nickel nanoparticles (NP), which constitute selective hydrogenation catalysts. For example, immobilization of fructose and Ni(OAc)2 on silica and subsequent pyrolysis under inert atmosphere produced graphitic shells encapsulated Ni-NP with uniform size and distribution. Interestingly, fructose acts as structure controlling compound to generate specific graphitic layers and the formation of monodisperse NP. The resulting stable and reusable catalysts allow for stereo- and chemoselective semihydrogenation of functionalized and structurally diverse alkynes in high yields and selectivity. © 2019 The Author(s

The value of diversity in cognitive science

A recent article (Núñez et al., 2019) claims that cognitive science, while starting off as a multidisciplinary enterprise, has “failed to transition to a mature inter‐disciplinary coherent field.” Two indicators reported in support of this claim target one of the two journals of the Cognitive Science Society, Cognitive Science , depicting cognitive science as an increasingly monodisciplinary subfield which is dominated by psychology. With a focus on the society's other journal, Topics in Cognitive Science , the present commentary reveals a greater degree of interdisciplinarity and discusses the relative values of diversity and integration for the field.publishedVersio

Nonclassical correlations of phase noise and photon number in quantum nondemolition measurements

The continuous transition from a low resolution quantum nondemolition measurement of light field intensity to a precise measurement of photon number is described using a generalized measurement postulate. In the intermediate regime, quantization appears as a weak modulation of measurement probability. In this regime, the measurement result is strongly correlated with the amount of phase decoherence introduced by the measurement interaction. In particular, the accidental observation of half integer photon numbers preserves phase coherence in the light field, while the accidental observation of quantized values increases decoherence. The quantum mechanical nature of this correlation is discussed and the implications for the general interpretation of quantization are considered.Comment: 16 pages, 5 figures, final version to be published in Phys. Rev. A, Clarifications of the nature of the measurement result and the noise added in section I

Being in front is good—but where is in front? Preferences for spatial referencing affect evaluation

Speakers of English frequently associate location in space with valence, as in moving up and down the “social ladder.” If such an association also holds for the sagittal axis, an object “in front of” another object would be evaluated more positively than the one “behind.” Yet how people conceptualize relative locations depends on which frame of reference (FoR) they adopt—and hence on cross‐linguistically diverging preferences. What is conceptualized as “in front” in one variant of the relative FoR (e.g., translation) is “behind” under another variant (reflection), and vice versa. Do such diverging conceptualizations of an object's location also lead to diverging evaluations? In two studies employing an implicit association test, we demonstrate, first, that speakers of German, Chinese, and Japanese indeed evaluate the object “in front of” another object more positively than the one “behind.” Second, and crucially, the reversal of which object is conceptualized as “in front” involves a corresponding reversal of valence, suggesting an impact of linguistically imparted FoR preferences on evaluative processes.publishedVersio

Iron/N-doped graphene nano-structured catalysts for general cyclopropanation of olefins

The first examples of heterogeneous Fe-catalysed cyclopropanation reactions are presented. Pyrolysis of in situ-generated iron/phenanthroline complexes in the presence of a carbonaceous material leads to specific supported nanosized iron particles, which are effective catalysts for carbene transfer reactions. Using olefins as substrates, cyclopropanes are obtained in high yields and moderate diastereoselectivities. The developed protocol is scalable and the activity of the recycled catalyst after deactivation can be effectively restored using an oxidative reactivation protocol under mild conditions

The maximum modulus of a trigonometric trinomial

Let Lambda be a set of three integers and let C_Lambda be the space of 2pi-periodic functions with spectrum in Lambda endowed with the maximum modulus norm. We isolate the maximum modulus points x of trigonometric trinomials T in C_Lambda and prove that x is unique unless |T| has an axis of symmetry. This permits to compute the exposed and the extreme points of the unit ball of C_Lambda, to describe how the maximum modulus of T varies with respect to the arguments of its Fourier coefficients and to compute the norm of unimodular relative Fourier multipliers on C_Lambda. We obtain in particular the Sidon constant of Lambda

Information and noise in quantum measurement

Even though measurement results obtained in the real world are generally both noisy and continuous, quantum measurement theory tends to emphasize the ideal limit of perfect precision and quantized measurement results. In this article, a more general concept of noisy measurements is applied to investigate the role of quantum noise in the measurement process. In particular, it is shown that the effects of quantum noise can be separated from the effects of information obtained in the measurement. However, quantum noise is required to ``cover up'' negative probabilities arising as the quantum limit is approached. These negative probabilities represent fundamental quantum mechanical correlations between the measured variable and the variables affected by quantum noise.Comment: 16 pages, short comment added in II.B., final version for publication in Phys. Rev.