Distance Powers and Distance Matrices of Integral Cayley Graphs over Abelian Groups

It is shown that distance powers of an integral Cayley graph over an abelian group are again integral Cayley graphs over that group. Moreover, it is proved that distance matrices of integral Cayley graphs over abelian groups have integral spectrum

Brief Studies

The Pastor, Modern Science, and our Societ

Emerging Standards for Implied Actions Under Federal Statutes

This article will examine the theoretical basis for finding implied causes of action in legislation and the development of the implication doctrine in the federal courts. In particular, the Cort v. Ash case will be discussed, both in terms of the standards articulated by the Supreme Court in dicta and the potential impact of Cort on the law of implied remedies

COMPETITIVE GRANTS AND THE FUNDING OF AGRICULTURAL RESEARCH IN THE U.S.

To increase the efficiency of the public agricultural R&D system, expanded use of competitive grants to fund state institutions has been advocated. This paper characterizes different funding instruments and empirically assesses the effects of changes in mechanism use. Factors associated with greater levels of competitive grants are modeled.Research and Development/Tech Change/Emerging Technologies,

Waves of DNA: Propagating excitations in extended nanoconfined polymers

We use a nanofluidic system to investigate the emergence of thermally driven collective phenomena along a single polymer chain. In our approach, a single DNA molecule is confined in a nanofluidic slit etched with arrays of embedded nanocavities; the cavity lattice is designed so that a single chain occupies multiple cavities. Fluorescent video-microscopy data shows fluctuations in intensity between cavities, including waves of excess fluorescence that propagate across the cavity-straddling molecule, corresponding to propagating fluctuations of contour overdensity in the cavities. The transfer of DNA between neighboring pits is quantified by examining the correlation in intensity fluctuations between neighboring cavities. Correlations grow from an anticorrelated minimum to a correlated maximum before decaying, corresponding to a transfer of contour between neighboring cavities at a fixed transfer time scale. The observed dynamics can be modeled using Langevin dynamics simulations and a minimal lattice model of coupled diffusion. This study shows how confinement-based sculpting of the polymer equilibrium configuration, by renormalizing the physical system into a series of discrete cavity states, can lead to new types of dynamic collective phenomena.Natural Sciences and Engineering Research Council of Canada (Grant NSERC-DG, 386212-10)Canada Foundation for InnovationNatural Sciences and Engineering Research Council of Canada (Postdoctoral Fellowship

Back-Translation Practices in Organizational Research: Avoiding Loss in Translation

As organizational research continues to globalize, scholars increasingly must translate established scales into languages other than those in which the scales were originally developed. In organizational psychology research, back-translation is the dominant procedure for translating scales. Back-translation has notable strengths in maintaining the psychometric properties of an established scale in a translated version. However, cross-cultural methodologists have argued that in its most basic form, back-translation often does not result in translations with acceptable levels of equivalence between original and translated research materials. Fortunately, there are complementary procedures to back-translation that can evaluate and strengthen the extent to which scale translations have achieved equivalence between original and translated versions of scales. But how often organizational researchers use and report these procedures in tandem with back-translation is unclear. This article aims to address this lack of clarity by evaluating the state of the use of back-translation in organizational psychology research by reviewing every study in Journal of Applied Psychology that has employed translation over the past nearly 25 years (k = 333). Our findings suggest that the majority of the time that researchers engage in translation procedures, they report having done so. At the same time, the details of these procedures are commonly underreported, making it unclear whether additional techniques beyond back-translation have been used to examine and demonstrate equivalence between original and translated versions of scales. Based on the results of our review, we develop a set of recommendations for conducting and reporting scale translations in organizational research

Knots modify the coil–stretch transition in linear DNA polymers

We perform single-molecule DNA experiments to investigate the relaxation dynamics of knotted polymers and examine the steady-state behavior of knotted polymers in elongational fields. The occurrence of a knot reduces the relaxation time of a molecule and leads to a shift in the molecule's coil-stretch transition to larger strain rates. We measure chain extension and extension fluctuations as a function of strain rate for unknotted and knotted molecules. The curves for knotted molecules can be collapsed onto the unknotted curves by defining an effective Weissenberg number based on the measured knotted relaxation time in the low extension regime, or a relaxation time based on Rouse/Zimm scaling theories in the high extension regime. Because a knot reduces a molecule's relaxation time, we observe that knot untying near the coil-stretch transition can result in dramatic changes in the molecule's conformation. For example, a knotted molecule at a given strain rate can experience a stretch-coil transition, followed by a coil-stretch transition, after the knot partially or fully unties.National Science Foundation (U.S.) (Grant CBET-1602406