3,338 research outputs found
F18RS SGR No. 15 (Floor Crew)
A RESOLUTION
To congratulate the LSU Building Services Floor Crew for their outstanding work during the year 201
S18RS SGR No. 14 (Campus Transit)
A RESOLUTION
To urge and request LSU Parking and Transportation to modify the LSU Tiger Trail Night A operations and the LSU Campus Transit system webpage and operational hour
S18RS SGR No. 15 (STD Lab Tests)
A RESOLUTION
TO URGE AND REQUEST THE LSU STUDENT HEALTH CENTER TO consider providing A PACKAGE FOR COMMON SEXUALLY TRANSMISSITED DISEASE (STD) LABORATORY TESTS at a fair pric
Nearly Blinking-Free, High-Purity Single-Photon Emission by Colloidal InP/ZnSe Quantum Dots
Colloidal core/shell InP/ZnSe quantum dots (QDs), recently produced using an
improved synthesis method, have a great potential in life-science applications
as well as in integrated quantum photonics and quantum information processing
as single-photon emitters. Single-particle spectroscopy of 10-nm QDs with
3.2-nm cores reveals strong photon antibunching attributed to fast (70-ps)
Auger recombination of multiple excitons. The QDs exhibit very good
photostability under strong optical excitation. We demonstrate that the
antibunching is preserved when the QDs are excited above the saturation
intensity of the fundamental-exciton transition. This result paves the way
towards their usage as high-purity on-demand single-photon emitters at room
temperature. Unconventionally, despite the strong Auger blockade mechanism,
InP/ZnSe QDs also display very little luminescence intermittency ("blinking"),
with a simple on/off blinking pattern. The analysis of single-particle
luminescence statistics places these InP/ZnSe QDs in the class of nearly
blinking-free QDs, with emission stability comparable to state-of-the-art
thick-shell and alloyed-interface CdSe/CdS, but with improved single-photon
purity.Comment: 15 pages, 5 figure
Multiscale dynamics of branching morphogenesis.
Branching morphogenesis is a prototypical example of complex three-dimensional organ sculpting, required in multiple developmental settings to maximize the area of exchange surfaces. It requires, in particular, the coordinated growth of different cell types together with complex patterning to lead to robust macroscopic outputs. In recent years, novel multiscale quantitative biology approaches, together with biophysical modelling, have begun to shed new light of this topic. Here, we wish to review some of these recent developments, highlighting the generic design principles that can be abstracted across different branched organs, as well as the implications for the broader fields of stem cell, developmental and systems biology.wellcome trust
royal societ
S18RS SGR No. 6 (Solar Power)
A RESOLUTION
To urge and request LSU Facility and Property Oversight to pursue and sign a solar purchase power agreement with a solar technology develope
Farmers’ preferences for cotton cultivation characteristics : a discrete choice experiment in Burkina Faso
While a fierce debate about the advantages and disadvantages of genetically modified crops is ongoing, it is surprising that farmers are often not consulted. In Burkina Faso, where insect resistant Bollgard II (R) cotton (further termed Bt cotton) was commercially released in 2008, studies highlight that cotton producers are in general satisfied with the reduction in insecticide use while the economic benefits are a source of controversy. To gain insight into farmers' preferences towards attributes in cotton cultivation, a discrete choice experiment (DCE) was developed. Five key attributes were identified to describe improved cotton varieties: seed development and provenance, seed costs, yield, required number of insecticide sprays, and preservation of agricultural practices. Farm-gate surveys were conducted among 324 cotton farmers in Western Burkina Faso. The results show that overall, farmers have a positive preference towards yield improvements and a negative preference towards pure private seed development and towards an increase in the requested number of insecticide applications or in the seed costs. According to their varieties at the time of the surveys (Bt and non-Bt), a difference was observed regarding their preferences for a status quo situation, indicating that those growing Bt had a stronger preference to keep the status quo than non-Bt farmers. When dividing the sample in segments based on the farm size, it was shown that there were different preferences with respect to the development of the variety and the required number of insecticide applications. Overall, it can be concluded from this study that economic benefits (linked to higher yields, lower seed costs, or reduced pesticide use) shape farmer's preferences
Statistical theory of branching morphogenesis
Branching morphogenesis remains a subject of abiding interest. Although much is
known about the gene regulatory programs and signaling pathways that operate at
the cellular scale, it has remained unclear how the macroscopic features of branched
organs, including their size, network topology and spatial patterning, are encoded.
Lately, it has been proposed that, these features can be explained quantitatively in
several organs within a single unifying framework. Based on large-
scale organ recon
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structions and cell lineage tracing, it has been argued that morphogenesis follows
from the collective dynamics of sublineage-
restricted self-
renewing progenitor cells,
localized at ductal tips, that act cooperatively to drive a serial process of ductal elon
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gation and stochastic tip bifurcation. By correlating differentiation or cell cycle exit
with proximity to maturing ducts, this dynamic results in the specification of a com-
plex network of defined density and statistical organization. These results suggest
that, for several mammalian tissues, branched epithelial structures develop as a self-
organized process, reliant upon a strikingly simple, but generic, set of local rules,
without recourse to a rigid and deterministic sequence of genetically programmed
events. Here, we review the basis of these findings and discuss their implications
Probabilistic sequence alignments: realistic models with efficient algorithms
Alignment algorithms usually rely on simplified models of gaps for
computational efficiency. Based on an isomorphism between alignments and
physical helix-coil models, we show in statistical mechanics that alignments
with realistic laws for gaps can be computed with fast algorithms. Improved
performances of probabilistic alignments with realistic models of gaps are
illustrated. Probabilistic and optimization formulations are compared, with
potential implications in many fields and perspectives for computationally
efficient extensions to Markov models with realistic long-range interactions
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