Determination of Fluorescence Polarization and Absorption Anisotropy in Molecular Complexes Having Threefold Rotational Symmetry

The current work concerns investigation of the polarization properties of complex molecular ensembles exhibiting threefold (C3) rotational symmetry, particularly with regard to the interplay between their structure and dynamics of internal energy transfer. We assume that the molecules or chromophores in such complexes possess strongly overlapped spectra both for absorption and fluorescence. Such trimeric structures are widely found in biological preparations, as for example the trimer of C-phycocyanin (C-PC). Higher order aggregates, e.g. hex-amers and three-hexamer rods, are also investigated and compared with the trimer case. The theory addresses both steady-state and 8-pulse excitation and establishes some links between them. Monochromophoric, bichro-mophoric and trichromophoric molecular complexes are individually examined. For steady-state excitation, analytical formulas are reported for the degree of fluorescence polarization and absorption anisotropy. It is shown that the polarization is dependent on the chromophore inclination relative to the symmetry axis, the relative efficiencies of absorption and fluorescence by chromophores of different spectral types, and the rates of energy equilibration. To assess the validity of the theory, it has been applied to C-PC aggregates. Here it was found that different C-PC aggregates provide practically identical polarization response. For S-pulse excitation we give analytical formulas for determination of the fluorescence depolarization, and also the depolarization associated with absorption recovery, both for a monochromophoric trimer and some particular cases of bichromophoric trimer. More complicated systems are analyzed by computer modeling. Thus it transpires that the initial polarization anisotropy r(t = 0) takes the value 0.4 for all considered aggregates; the long-time limit r(t →∞) has about the same value as is associated with steady-state excitation. We also show that with steady-state excitation the degree of fluorescence polarization is practically equal for various C3 aggregates of C-PC, and that the major factor determining the polarization is the chromophore orientation relative to the symmetry axis

Unsupervised Distance Metric Learning Using Predictability

Distance-based learning methods, like clustering and SVMs, are dependent on good distance metrics. This paper does unsupervised metric learning in the context of clustering. We seek transformations of data which give clean and well separated clusters where clean clusters are those for which membership can be accurately predicted. The transformation (hence distance metric) is obtained by minimizing the blur ratio, which is defined as the ratio of the within cluster variance divided by the total data variance in the transformed space. For minimization we propose an iterative procedure, Clustering Predictions of Cluster Membership (CPCM). CPCM alternately (a) predicts cluster memberships (e.g., using linear regression) and (b) clusters these predictions (e.g., using k-means). With linear regression and k-means, this algorithm is guaranteed to converge to a fixed point. The resulting clusters are invariant to linear transformations of original features, and tend to eliminate noise features by driving their weights to zero

Fertilizing Pasture and Hayland

Guide to fertilizing pasture and hayland discusses fertilization for forage production, established grass-legume mixtures, new seedings, and seed production

Theology, News and Notes - Vol. 41, No. 03

Theology News & Notes was a theological journal published by Fuller Theological Seminary from 1954 through 2014.https://digitalcommons.fuller.edu/tnn/1121/thumbnail.jp

Mapping epilepsy-specific patient-reported outcome measures for children to a proposed core outcome set for childhood epilepsy

This is the final version. Available on open access from Elsevier via the DOI in this recordObjective: The objectives of the study were to (1) map questions in epilepsy-specific patient-reported outcome measures (PROMs) of children's health-related quality of life (HRQoL) to a proposed core outcome set (COS) for childhood epilepsy research and (2) gain insight into the acceptability of two leading candidate PROMs. Method: We identified 11 epilepsy-specific PROMs of children's HRQoL (17 questionnaire versions) in a previous systematic review. Each item from the PROMs was mapped to 38 discrete outcomes across 10 domains of the COS: seizures, sleep, social functioning, mental health, cognition, physical functioning, behavior, adverse events, family life, and global quality of life. We consulted with three children with epilepsy and six parents of children with epilepsy in Patient Public Involvement and Engagement (PPIE) work to gain an understanding of the acceptability of the two leading PROMs from our review of measurement properties: Quality of Life in Childhood Epilepsy (QOLCE-55) and Health-Related Quality of Life Measure for Children with Epilepsy (CHEQOL). Results: Social Functioning is covered by all PROMs except DISABKIDS and G-QOLCE and Mental Health is covered by all PROMs except G-QOLCE and Hague Restrictions in Childhood Epilepsy Scale (HARCES). Only two PROMs (Epilepsy and Learning Disability Quality of Life (ELDQOL) and Glasgow Epilepsy Outcome Scale (GEOS-YP)) have items that cover the Seizure domain. The QOLCE-55 includes items that cover the domains of Physical Functioning, Social Functioning, Behavior, Mental Health, and Cognition. The CHEQOL parent and child versions cover the same domains as QOLCE-55 except for Physical Functioning and Behavior, and the child version has one item that covers the discrete outcome of Overall Quality of Life and one item that covers the discrete outcome of Relationship with parents and siblings. The QOLCE-55 parent version was acceptable to the parents we consulted with, and CHEQOL parent and child versions were described as acceptable to our child and parent advisory panel members. Significance: Mapping items from existing epilepsy-specific PROMs for children is an important step in operationalizing our COS for childhood epilepsy research, alongside evaluation of their measurement properties. Two leading PROMS, QOLCE-55 and CHEQOL, cover a wide range of domains from our COS and would likely be used in conjunction with assessment tools selected for specific study objectives. The PPIE work provided practical insights into the administration and acceptability of candidate PROMs in appropriate context. We promote our COS as a framework for selecting outcomes and PROMs for future childhood epilepsy evaluative research.National Institute for Health Research (NIHR)Canadian Institutes of Health ResearchWaterloo FoundationCharles Sykes Epilepsy Research Trus

Shoreline Evolution Lancaster County, Virginia Chesapeake Bay and Rappahannock River Shorelines 2006

Shoreline evolution is the change in shore position through time. In fact, it is the material resistance of the coastal geologic underpinnings against the impinging hydrodynamic (and aerodynamic) forces. Along the shores of Chesapeake Bay and Rappahannock River, it is a process-response system. The processes at work include winds, waves, tides and currents, which shape and modify coastlines by eroding, transporting and depositing sediments. The shore line is commonly plotted and measured to provide a rate of change but it is as important to understand the geomorphic patterns of change. Shore analysis provides the basis to know how a particular coast has changed through time and how it might proceed in the future. The purpose of this report is to document how the dunes along the Bay and river shores of Lancaster (Figure 1) have evolved since 1937. Aerial imagery was taken for most of the Bay region beginning that year, and it is this imagery that allows one to assess the geomorphic nature of shore change. Aerial imagery shows how the coast has changed, how beaches, dunes, bars, and spits have grown or decayed, how barriers have breached, how inlets have changed course, and how one shore type has displaced another or has not changed at all. Shore change is a natural process but, quite often, the impacts of man through shore hardening or inlet stabilization come to dominate a given shore reach. Most of the change in shore positions will be quantified in this report. Others, particularly very irregular coasts, around inlets, and other complicated areas will be subject to interpretation

Dune Evolution Middlesex County, Virginia Rappahannock River and Piankatank River Shorelines

Shoreline evolution is the change in shore position through time. In fact, it is the material resistance of the coastal geologic underpinnings against the impinging hydrodynamic (and aerodynamic) forces. Along the shores of Chesapeake Bay, it is a process-response system. The processes at work include winds, waves, tides and currents, which shape and modify coastlines by eroding, transporting and depositing sediments. The shore line is commonly plotted and measured to provide a rate of change but it is as important to understand the geomorphic patterns of change. Shore analysis provides the basis to know how a particular coast has changed through time and how it might proceed in the future. The purpose of this report is to document how the dunes on Piankatank River and Rappahannock River shores of Middlesex (Figure 1) have evolved since 1937. Aerial imagery was taken for most of the Bay region beginning that year, and it is this imagery that allows one to assess the geomorphic nature of shore change. Aerial imagery shows how the coast has changed, how beaches, dunes, bars, and spits have grown or decayed, how barriers have breached, how inlets have changed course, and how one shore type has displaced another or has not changed at all. Shore change is a natural process but, quite often, the impacts of man through shore hardening or inlet stabilization come to dominate a given shore reach. Most of the change in shore positions where dunes occur will be quantified in this report. Others, particularly very irregular coasts, around inlets, and other complicated areas will be subject to interpretation

MCG+00-32-16: An Irregular Galaxy Close to the Lowest Redshift Absorber on the 3C 273 Line of Sight

MCG+00-32-16 is the galaxy closest in position-velocity space to the lowest redshift Ly$\alpha$ absorber along the line-of-sight to the quasar 3C 273. Its projected separation is 204 (d/19 Mpc) kpc, where d is the distance from the Milky Way to the galaxy, and the redshift difference is only 94 km/s; HI 1225+01 is slightly closer in projected separation to the absorber, but has a greater redshift difference. We present HI synthesis array mapping and CCD photometry in B and R for MCG+00-32-16. The HI disk is rotating in such a way that the side of the galaxy closer to the sight-line to the quasar has the larger velocity difference from the absorber. The absorber may be a ``failed dwarf'' member of a poor galaxy group of which MCG+00-32-16 and HI 1225+01 are the only members to have formed stars.Comment: 14 pages, 9 figures, accepted by Astrophysical Journa