The Wiley Handbook of Personal Construct Psychology is the definitive new reference for the field, providing a state-of-the-art review of PCP which focuses on the theory and its philosophy, ...methodology, areas of application and future horizons * A definitive new reference work for the field of personal construct psychology, featuring leading international figures in the field * Each section begins with a concise chapter that reviews the literature in the area concerned and highlights new developments * Covers theory, history, methodology and a wealth of new and established applications including education, grief and meaning reconstruction, sexuality, organizational consultancy and personal construct coaching * Draws on published and previously unpublished work by pioneers including Fay Fransella and Miller Mair
Liquid–liquid phase separation (LLPS) of proteins and other biomolecules play a critical role in the organization of extracellular materials and membrane‐less compartmentalization of intra‐organismal ...spaces through the formation of condensates. Structural properties of such mesoscopic droplet‐like states were studied by spectroscopy, microscopy, and other biophysical techniques. The temperature dependence of biomolecular LLPS has been studied extensively, indicating that phase‐separated condensed states of proteins can be stabilized or destabilized by increasing temperature. In contrast, the physical and biological significance of hydrostatic pressure on LLPS is less appreciated. Summarized here are recent investigations of protein LLPS under pressures up to the kbar‐regime. Strikingly, for the cases studied thus far, LLPSs of both globular proteins and intrinsically disordered proteins/regions are typically more sensitive to pressure than the folding of proteins, suggesting that organisms inhabiting the deep sea and sub‐seafloor sediments, under pressures up to 1 kbar and beyond, have to mitigate this pressure‐sensitivity to avoid unwanted destabilization of their functional biomolecular condensates. Interestingly, we found that trimethylamine‐N‐oxide (TMAO), an osmolyte upregulated in deep‐sea fish, can significantly stabilize protein droplets under pressure, pointing to another adaptive advantage for increased TMAO concentrations in deep‐sea organisms besides the osmolyte's stabilizing effect against protein unfolding. As life on Earth might have originated in the deep sea, pressure‐dependent LLPS is pertinent to questions regarding prebiotic proto‐cells. Herein, we offer a conceptual framework for rationalizing the recent experimental findings and present an outline of the basic thermodynamics of temperature‐, pressure‐, and osmolyte‐dependent LLPS as well as a molecular‐level statistical mechanics picture in terms of solvent‐mediated interactions and void volumes.
Protein–protein interactions: In this Review, we show that protein condensates are typically more sensitive to pressure than the folding of proteins, suggesting that organisms thriving in the deep sea must mitigate this pressure sensitivity.
We study the quantum channel version of Shannon's zero-error capacity problem. Motivated by recent progress on this question, we propose to consider a certain subspace of operators (so-called ...operator systems) as the quantum generalization of the adjacency matrix, in terms of which the zero-error capacity of a quantum channel, as well as the quantum and entanglement-assisted zero-error capacities can be formulated, and for which we show some new basic properties. Most importantly, we define a quantum version of Lovász' famous ϑ function on general operator systems, as the norm-completion (or stabilization) of a "naive" generalization of ϑ. We go on to show that this function upper bounds the number of entanglement-assisted zero-error messages, that it is given by a semidefinite program, whose dual we write down explicitly, and that it is multiplicative with respect to the tensor product of operator systems (corresponding to the tensor product of channels). We explore various other properties of the new quantity, which reduces to Lovász' original ϑ in the classical case, give several applications, and propose to study the operator systems associated with channels as "noncommutative graphs," using the language of Hilbert modules.
Zeolites play a crucial part in acid-base heterogeneous catalysis. Fundamental insight into their internal architecture is of great importance for understanding their structure-function ...relationships. Here, we report on a new approach correlating confocal fluorescence microscopy with focused ion beam-electron backscatter diffraction, transmission electron microscopy lamelling and diffraction, atomic force microscopy and X-ray photoelectron spectroscopy to study a wide range of coffin-shaped MFI-type zeolite crystals differing in their morphology and chemical composition. This powerful combination demonstrates a unified view on the morphology-dependent MFI-type intergrowth structures and provides evidence for the presence and nature of internal and outer-surface barriers for molecular diffusion. It has been found that internal-surface barriers originate not only from a 90 degrees mismatch in structure and pore alignment but also from small angle differences of 0.5 degrees-2 degrees for particular crystal morphologies. Furthermore, outer-surface barriers seem to be composed of a silicalite outer crust with a thickness varying from 10 to 200 nm.
The stationary resistive field distribution on the gas-solid interface along epoxy resin insulators is theoretically and experimentally investigated. Due to the phenomenon that the charge carriers ...necessary for the conduction process originate from natural ionization and a constant generation rate is assumed, the resulting electric conductivity of gases under dc voltage stress is nonlinearly depending on the field strength. A simulation model which considers the relevant characteristic is used to calculate the electric field in gas-solid insulation systems. The influence of the ion pair generation rate of the gas, the electric field strength and the surface conductivity of an insulator on the resistive field distribution is investigated. The results are compared to simulations, in which the electric conductivity of the gas is assumed to be constant. The simulations are verified by measurements of the surface potential along an epoxy resin insulator under dc voltage.
ABSTRACT
Massive stars are strong sources of far-ultraviolet radiation that can be hostile to the evolution of protoplanetary discs, driving mass-loss by external photoevaporation and shortening ...disc-dissipation time-scales. Their effect may also reduce the time-scale of angular momentum exchanges between the disc and host star during the early pre-main-sequence phase. To improve our understanding of the environmental influence on the rotational history of stars, we developed a model that considers the influence of the local far-ultraviolet radiation on the spin evolution of low mass stars. Our model includes an assumption of disc locking, which fixes the rotation rate during the star-disc-interaction phase, with the duration of this phase parametrized as a function of the local far-ultraviolet radiation and stellar mass (in the range of 0.1–1.3 M⊙). In this way, we demonstrate how the feedback from massive stars can significantly influence the spin evolution of stars and explain the mass dependence observed in period-mass distributions of young regions like Upper Sco and NGC 2264. The high far-ultraviolet environments of high-mass stars can skew the period distribution of surrounding stars towards fast-rotation, explaining the excess of fast-rotating stars in the open cluster h Per. The proposed link between rotation and the pre-main-sequence environment opens new avenues for interpreting the rotational distributions of young stars. For example, we suggest that stellar rotation may be used as a tracer for the primordial ultraviolet irradiation for stars up to ∼1 Gyr, which offers a potential method to connect mature planetary systems to their birth environment.
Abstract
The majority of stars form in a clustered environment. This has an impact on the evolution of surrounding protoplanetary discs (PPDs) due to either photoevaporation or tidal truncation. ...Consequently, the development of planets depends on formation environment. Here, we present the first thorough investigation of tidally induced angular momentum loss in PPDs in the distant regime, partly motivated by claims in the literature for the importance of distant encounters in disc evolution. We employ both theoretical predictions and dynamical/hydrodynamical simulations in 2D and 3D. Our theoretical analysis is based on that of Ostriker (1994) and leads us to conclude that in the limit that the closest approach distance xmin ≫ r, the radius of a particle ring, the fractional change in angular momentum scales as (xmin/r)−5. This asymptotic limit ensures that the cumulative effect of distant encounters is minor in terms of its influence on disc evolution. The angular momentum transfer is dominated by the m = 2 Lindblad resonance for closer encounters and by the m = 1, ω = 0 Lindblad resonance at large xmin/r. We contextualize these results by comparing expected angular momentum loss for the outer edge of a PPD due to distant and close encounters. Contrary to the suggestions of previous works, we do not find that distant encounters contribute significantly to angular momentum loss in PPDs. We define an upper limit for closest approach distance where interactions are significant as a function of arbitrary host to perturber mass ratio M2/M1.
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