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A two-step method for identifying photopigment opsin and rhodopsin gene sequences underlying human color vision phenotypes.
PurposeTo present a detailed, reliable long range-PCR and sequencing (LR-PCR-Seq) procedure to identify human opsin gene sequences for variations in the long wavelength-sensitive (OPN1LW), medium wavelength-sensitive (OPN1MW), short wavelength-sensitive (OPN1SW), and rhodopsin (RHO) genes.MethodsColor vision was assessed for nine subjects using the Farnsworth-Munsell 100 hue test, Ishihara pseudoisochromatic plates, and the Rabin cone-contrast threshold procedure (ColorDX, Konan Medical). The color vision phenotypes were normal trichromacy (n = 3), potential tetrachromacy (n = 3), dichromacy (n = 2), and unexplained low color vision (n = 1). DNA was isolated from blood or saliva and LR-PCR amplified into individual products: OPN1LW (4,045 bp), OPN1MW (4,045 bp), OPN1SW (3,326 bp), and RHO (6,715 bp). Each product was sequenced using specific internal primer sets. Analysis was performed with Mutation Surveyor software.ResultsThe LR-PCR-Seq technique identified known single nucleotide polymorphisms (SNPs) in OPN1LW and OPN1MW gene codons (180, 230, 233, 277, and 285), as well as those for lesser studied codons (174, 178, 236, 274, 279, 298 and 309) in the OPN1LW and OPN1MW genes. Additionally, six SNP variants in the OPN1MW and OPN1LW genes not previously reported in the NCBI dbSNP database were identified. An unreported poly-T region within intron 5(c.36+126) of the rhodopsin gene was also found, and analysis showed it to be highly conserved in mammalian species.ConclusionsThis LR-PCR-Seq procedure (single PCR reaction per gene followed by sequencing) can identify exonic and intronic SNP variants in OPN1LW, OPN1MW, OPN1SW, and rhodopsin genes. There is no need for restriction enzyme digestion or multiple PCR steps that can introduce errors. Future studies will combine the LR-PCR-Seq with perceptual behavior measures, allowing for accurate correlations between opsin genotypes, retinal photopigment phenotypes, and color perception behaviors
Results from the Analysis of Crystal Ball Meson Production Measurements at BNL
The Crystal Ball spectrometer, with its nearly complete angular coverage, is
an efficient detector of photon and neutron final states. While installed in
the C6 beamline of the Alternating Gradient Synchrotron (AGS) of Brookhaven
National Laboratory (BNL), this feature was used in a series of precise
measurements of reactions with all-neutral final states. Here we concentrate on
the analysis of data from the pion-induced reactions: pi- p --> gamma n, pi- p
--> pi0 n, pi- p --> eta n, and pi- p --> pi0 pi0 n.Comment: Conference contribution to MESON 2006 - Krakow, Pola
Ultraviolet and yellow reflectance but not fluorescence is important for visual discrimination of conspecifics by Heliconius erato
Toxic Heliconius butterflies have yellow hindwing bars that – unlike those of their closest relatives – reflect ultraviolet (UV) and long wavelength light, and also fluoresce. The pigment in the yellow scales is 3-hydroxy-DL-kynurenine (3-OHK), which is found in the hair and scales of a variety of animals. In other butterflies like pierids with color schemes characterized by independent sources of variation in UV and human-visible yellow/orange, behavioral experiments have generally implicated the UV component as most relevant to mate choice. This has not been addressed in Heliconius butterflies, where variation exists in analogous color components, but moreover where fluorescence due to 3-OHK could also contribute to yellow wing coloration. In addition, the potential cost due to predator visibility is largely unknown for the analogous well-studied pierid butterfly species. In field studies with butterfly paper models, we show that both UV and 3-OHK yellow act as signals for H. erato when compared with models lacking UV or resembling ancestral Eueides yellow, respectively, but attack rates by birds do not differ significantly between the models. Furthermore, measurement of the quantum yield and reflectance spectra of 3-OHK indicates that fluorescence does not contribute to the visual signal under broad-spectrum illumination. Our results suggest that the use of 3-OHK pigmentation instead of ancestral yellow was driven by sexual selection rather than predation
-meson in nuclear matter
The -nucleon (N) interactions are deduced from the heavy baryon
chiral perturbation theory up to the next-to-leading-order terms. Combining the
relativistic mean-field theory for nucleon system, we have studied the
in-medium properties of -meson. We find that all the elastic scattering
N interactions come from the next-to-leading-order terms. The N
sigma term is found to be about 280130 MeV. The off-shell terms are also
important to the in-medium properties of -meson. On application of the
latest determination of the N scattering length, the ratio of
-meson effective mass to its vacuum value is near , while
the optical potential is about MeV, at the normal nuclear density.Comment: 8 pages, 3 figures, to appear in PRC, many modification
Physics Opportunities with Meson Beams
Over the past two decades, meson photo- and electro-production data of
unprecedented quality and quantity have been measured at electromagnetic
facilities worldwide. By contrast, the meson-beam data for the same hadronic
final states are mostly outdated and largely of poor quality, or even
nonexistent, and thus provide inadequate input to help interpret, analyze, and
exploit the full potential of the new electromagnetic data. To reap the full
benefit of the high-precision electromagnetic data, new high-statistics data
from measurements with meson beams, with good angle and energy coverage for a
wide range of reactions, are critically needed to advance our knowledge in
baryon and meson spectroscopy and other related areas of hadron physics. To
address this situation, a state of-the-art meson-beam facility needs to be
constructed. The present paper summarizes unresolved issues in hadron physics
and outlines the vast opportunities and advances that only become possible with
such a facility.Comment: 46 pages, 10 figures, 4 table
Genome-wide analysis of ionotropic receptors provides insight into their evolution in Heliconius butterflies.
BACKGROUND: In a world of chemical cues, smell and taste are essential senses for survival. Here we focused on Heliconius, a diverse group of butterflies that exhibit variation in pre- and post-zygotic isolation and chemically-mediated behaviors across their phylogeny. Our study examined the ionotropic receptors, a recently discovered class of receptors that are some of the most ancient chemical receptors. RESULTS: We found more ionotropic receptors in Heliconius (31) than in Bombyx mori (25) or in Danaus plexippus (27). Sixteen genes in Lepidoptera were not present in Diptera. Only IR7d4 was exclusively found in butterflies and two expansions of IR60a were exclusive to Heliconius. A genome-wide comparison between 11 Heliconius species revealed instances of pseudogenization, gene gain, and signatures of positive selection across the phylogeny. IR60a2b and IR60a2d are unique to the H. melpomene, H. cydno, and H. timareta clade, a group where chemosensing is likely involved in pre-zygotic isolation. IR60a2b also displayed copy number variations (CNVs) in distinct populations of H. melpomene and was the only gene significantly higher expressed in legs and mouthparts than in antennae, which suggests a gustatory function. dN/dS analysis suggests more frequent positive selection in some intronless IR genes and in particular in the sara/sapho and melpomene/cydno/timareta clades. IR60a1 was the only gene with an elevated dN/dS along a major phylogenetic branch associated with pupal mating. Only IR93a was differentially expressed between sexes. CONCLUSIONS: All together these data make Heliconius butterflies one of the very few insects outside Drosophila where IRs have been characterized in detail. Our work outlines a dynamic pattern of IR gene evolution throughout the Heliconius radiation which could be the result of selective pressure to find potential mates or host-plants.This project is funded by a NASA grant (NNX10AM80H and NNX07AO30A) to RP, a NSF-DEB 1257839 to RP, NSF cooperative agreement DBI-0939454 to ADB, and a BBSRC grant H01439X and ERC grant ‘SpeciationGenetics’ to CDJ
Resistance to Digitisation: Curated Memory Cards Artefact
date-added: 2015-03-24 04:16:59 +0000 date-modified: 2015-03-24 04:16:59 +0000date-added: 2015-03-24 04:16:59 +0000 date-modified: 2015-03-24 04:16:59 +0000The act of networking in any context has some element of ceremonial performance attached to it. In an analogue world these performances have historically included the act of exchanging business cards. This ‘ceremony of networking’ has the potential to be altered by the emergence of new media, especially digital technology, displacing the old ceremony of business card exchanges and disrupting what can traditional be seen as networking. The history of business cards have shown that, despite several digital alternatives, they are still resistant to digitisation and so predominantly still physical and tangible. So, we sought to explore the ceremony around giving business cards as the sharing of ‘curated memory’, to better understand how and why we share and co-create curated memories with others. Including the sharing curated memories more generally, and the changing nature of networking, arising from the ever-increasing connectivity and digital embeddedness associated with the information age. Therefore, exploring the ceremony around needing, creating, sharing and using business cards, within different contexts and cultures. Also, identifying the tasks that people are trying to perform and optimise at different stages (before, during, and after) in a range of scenarios. Also, to explore how the ceremonies of networking might be significantly altered as a result of digital media and tools. The approach of using sets of cards around Who, How, Why and Where emerged from the need for a tool that could build narratives around the considerable diversity of the disjointed scenarios of networking we observed. So, the cards provide a reference by which to share general understanding in an entertaining and easily accessible manner. Second, provides a tool to summarise narratives from the scenarios we observed, and that we could then use to create new scenarios to explore insights such as post-meeting curation of ‘shared memories’ when networking. Third, define a number of ‘games’ to help anyone explore how to better understand and utilise aspects of networking in their current approaches, and challenge them to develop new approaches. Therefore, generating debate and self-reflection on the ways players use business cards themselves
Comparison of Communication Architectures for Spacecraft Modular Avionics Systems
This document is a survey of publicly available information concerning serial communication architectures used, or proposed to be used, in aeronautic and aerospace applications. It focuses on serial communication architectures that are suitable for low-latency or real-time communication between physically distributed nodes in a system. Candidates for the study have either extensive deployment in the field, or appear to be viable for near-term deployment. Eleven different serial communication architectures are considered, and a brief description of each is given with the salient features summarized in a table in appendix A. This survey is a product of the Propulsion High Impact Avionics Technology (PHIAT) Project at NASA Marshall Space Flight Center (MSFC). PHIAT was originally funded under the Next Generation Launch Technology (NGLT) Program to develop avionics technologies for control of next generation reusable rocket engines. After the announcement of the Space Exploration Initiative, the scope of the project was expanded to include vehicle systems control for human and robotics missions. As such, a section is included presenting the rationale used for selection of a time-triggered architecture for implementation of the avionics demonstration hardware developed by the project tea
Charge-Symmetry Violation in Pion Scattering from Three-Body Nuclei
We discuss the experimental and theoretical status of charge-symmetry
violation (CSV) in the elastic scattering of pi+ and pi- on 3H and 3He.
Analysis of the experimental data for the ratios r1, r2, and R at Tpi = 142,
180, 220, and 256 MeV provides evidence for the presence of CSV. We describe
pion scattering from the three-nucleon system in terms of single- and
double-scattering amplitudes. External and internal Coulomb interactions as
well as the Delta-mass splitting are taken into account as sources of CSV.
Reasonable agreement between our theoretical calculations and the experimental
data is obtained for Tpi = 180, 220, and 256 MeV. For these energies, it is
found that the Delta-mass splitting and the internal Coulomb interaction are
the most important contributions for CSV in the three-nucleon system. The CSV
effects are rather sensitive to the choice of pion-nuclear scattering
mechanisms, but at the same time, our theoretical predictions are much less
sensitive to the choice of the nuclear wave function. It is found, however,
that data for r2 and R at Tpi = 142 MeV do not agree with the predictions of
our model, which may indicate that there are additional mechanisms for CSV
which are important only at lower energies.Comment: 26 pages of RevTeX, 16 postscript figure
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