Quantifying finfish and blue crab use of created oyster reefs in the lower Chesapeake Bay

Structurally complex reefs created by the eastern oyster Crassostrea virginica provide a host of ecosystem services yet have experienced significant declines, prompting extensive restoration efforts. We investigate the use of created oyster reefs in the lower Bay by mobile finfish and blue crabs with field surveys and diet analysis. The results of this study provide insight into how restoration activities influence estuarine community dynamics and the provision of ecosystem services

The Effects of Massive Substructures on Image Multiplicities in Gravitati onal Lenses

Surveys for gravitational lens systems have typically found a significantly larger fraction of lenses with four (or more) images than are predicted by standard ellipsoidal lens models (50% versus 25-30%). We show that including the effects of smaller satellite galaxies, with an abundance normalized by the observations, significantly increases the expected number of systems with more than two images and largely explains the discrepancy. The effect is dominated by satellites with ~20% the luminosity of the primary lens, in rough agreement with the typical luminosities of the observed satellites. We find that the lens systems with satellites cannot, however, be dropped from estimates of the cosmological model based on gravitational lens statistics without significantly biasing the results.Comment: 23 pages, 7 figures, more discussion of sis vs sie and inclusion of uncorrelated contribution

Rank 3 permutation characters and maximal subgroups

In this paper we classify all maximal subgroups M of a nearly simple primitive rank 3 group G of type L=Omega_{2m+1}(3), m > 3; acting on an L-orbit E of non-singular points of the natural module for L such that 1_P^G <=1_M^G where P is a stabilizer of a point in E. This result has an application to the study of minimal genera of algebraic curves which admit group actions.Comment: 41 pages, to appear in Forum Mathematicu

Mass Spectral Fragmentation Study of Substituted 1,3-Diphenyl- 2-pyrazolines

The electron impact induced fragmentation of twenty two 1,3- -diphenyl-2-pyrazolines mono-, di- and trisubstituted in one or in both phenyl rings was studied by deuterium labelling, high and low resolution mass spectrometry, and ion kinetic energy spectroscopy. The fragmentation patterns are discussed taking into account especially the nature of the substituent and the position of substitution. The results, compared with those for the unsubstituted compound, showed that in general the phenyl ring substitution does not affect its fragmentation. The formation of stable quinoid-type ions directs many fragmentation pathways of methoxy substituted compounds

Mass Spectral Fragmentation Study of Substituted 1,3-Diphenyl- 2-pyrazolines

The electron impact induced fragmentation of twenty two 1,3- -diphenyl-2-pyrazolines mono-, di- and trisubstituted in one or in both phenyl rings was studied by deuterium labelling, high and low resolution mass spectrometry, and ion kinetic energy spectroscopy. The fragmentation patterns are discussed taking into account especially the nature of the substituent and the position of substitution. The results, compared with those for the unsubstituted compound, showed that in general the phenyl ring substitution does not affect its fragmentation. The formation of stable quinoid-type ions directs many fragmentation pathways of methoxy substituted compounds

End states, ladder compounds, and domain wall fermions

A magnetic field applied to a cross linked ladder compound can generate isolated electronic states bound to the ends of the chain. After exploring the interference phenomena responsible, I discuss a connection to the domain wall approach to chiral fermions in lattice gauge theory. The robust nature of the states under small variations of the bond strengths is tied to chiral symmetry and the multiplicative renormalization of fermion masses.Comment: 10 pages, 4 figures; final version for Phys. Rev. Let

Multiplicity-free representations of algebraic groups II

We continue our work (started in ``Multiplicity-free representations of algebraic groups", arXiv:2101.04476), on the program of classifying triples $(X,Y,V)$, where $X,Y$ are simple algebraic groups over an algebraically closed field of characteristic zero with $X<Y$, and $V$ is an irreducible module for $Y$ such that the restriction $V\downarrow X$ is multiplicity-free. In this paper we handle the case where $X$ is of type $A$, and is irreducibly embedded in $Y$ of type $B,C$ or $D$. It turns out that there are relatively few triples for $X$ of arbitrary rank, but a number of interesting exceptional examples arise for small ranks.Comment: 60 page