The biased evolution of generation time

Many life-history traits, like the age at maturity or adult longevity, are important determinants of the generation time. For instance, semelparous species whose adults reproduce once and die have shorter generation times than iteroparous species that reproduce on several occasions. A shorter generation time ensures a higher growth rate in stable environments where resources are in excess, and is therefore a positively selected feature in this (rarely met) situation. In a stable and limiting environment, all combination of traits (or strategies) that produce the same number of viable offspring on average are strictly neutral even when their generation times differ. We first study the evolution of life-history strategies with different generation times in this context, and show that those with the longest generation time represent the most likely evolutionary outcomes. Indeed, strategies with longer generation times generate fewer mutants per time unit, which makes them less likely to be replaced within a given time period. This `turnover bias' inevitably exists and favors the evolution of strategies with long generation times. Its real impact, however, should depend on the strength and direction of other evolutionary forces; selection for short generation times, for instance, may oppose turnover bias. Likewise, the evolutionary outcome depends on the strength of such selection and population size, comparably to other biases acting on the occurrence of mutations.Comment: Now we also study the evolution of development duration, suggesting that turnover bias is involved in the evolutionary dynamics of any trait linked with the generation tim

S02RS SGB No. 31 (Repeal SGB No. 9)

A BILL To Repeal SGB No. 9 of the 2001-2002 Legislative Session

S02RS SGB No. 32 (WOW)

A BILL To Appropriate one thousand- one hundred dollars ($1,100) to Women Organizing Women for the purpose of bringing Larry Kirkwood to the LSU Campus March 21, 2002, for a lecture and art exhibit

Aberration-free calibration for 3D single molecule localization microscopy

We propose a straightforward sample-based technique to calibrate the axial detection in 3D single molecule localization microscopy (SMLM). Using microspheres coated with fluorescent molecules, the calibration curves of PSF-shaping- or intensity-based measurements can be obtained for any required depth range from a few hundreds of nanometers to several tens of microns. This experimental method takes into account the effect of the spherical aberration without requiring computational correction.Comment: 8 pages, 2 figures. Submitted to Optics Letters on October 12th, 201

The Library Concierge Project at Stanford University

To meet the challenge of ensuring that library staff and scholars/patrons are aware of the full range of resources and services offered through the library, the Stanford University Libraries initiated a Library Concierge Project in November of 2011. This article describes the program and provides an assessment of how well the Library Concierge Project has met its goals of promoting a service-focused culture and educating staff. A description of the concierge concept in action is also provided, along with anecdotal evidence of the impact of the project on supported scholars

F01RS SGR No. 7 (Horticulture)

A RESOLUTION to affirm the permanent location of the Horticulture Hill Farm Teaching Facility on the LSU A&M Campu

S02RS SGR No. 15 (New Era Cap)

A RESOLUTION To show student support for LSU A&M to suspend its contract with New Era Cap Company

F01RS SGB No. 12 (Spectrum Alliance)

A BILL To appropriate two thousand one hundred fourteen dollars and eighty-six cents ($2114.86) to Spectrum Alliance to help defray the cost of attending the National Gay and Lesbian Task Force (NGLTF) Creating Change Conference in Milwaukee, Wisconsin on November 7-11, 200

In vivo endoscopic autofluorescence microspectro-imaging of bronchi and alveoli

Fibered confocal fluorescence microscopy (FCFM) is a new technique that can be used during a bronchoscopy to analyze the nature of the human bronchial and alveolar mucosa fluorescence microstructure. An endoscopic fibered confocal fluorescence microscopy system with spectroscopic analysis capability was developed allowing real-time, simultaneous images and emission spectra acquisition at 488 nm excitation using a flexible miniprobe that could be introduced into small airways. This flexible 1.4 mm miniprobe can be introduced into the working channel of a flexible endoscope and gently advanced through the bronchial tree to the alveoli. FCFM in conjunction with bronchoscopy is able to image the in vivo autofluorescence structure of the bronchial mucosae but also the alveolar respiratory network outside of the usual field of view. Microscopic and spectral analysis showed that the signal mainly originates from the elastin component of the bronchial subepithelial layer. In non smokers, the system images the elastin backbone of the aveoli. In active smokers, a strong autofluorescence signal appears from alveolar macrophages. The FCFM technique appears promising for in vivo exploration of the bronchial and alveolar extracellular matrix