Distribution, Abundance, and Age Structure of Red Snapper (Lutjanus campechanus) Caught on Research Longlines in U.S. Gulf of Mexico

Two pilot surveys were conducted in the northern Gulf of Mexico (Gulf) to determine the feasibility of sampling red snapper (Lutjanus campechanus) populations in offshore waters with bottom longline gear. The first pilot survey off Mississippi-Alabama was conducted in May 1999 and yielded a total of seven snapper from 60 stations. The second pilot survey was off Texas in June 2000 and yielded a total of 76 snapper from 44 stations. The catch per unit effort was 0.12 red snapper/100 hook hr [coefficient of variation (CV) = 0.54] in 1999 and 1.73 red snapper/100 hook hr (CV = 0.21) in 2000. Otoliths were removed from all collected red snapper, and ages were assigned with an average percent error of 3.71%. Red snapper from the 1999 survey ranged from 405 to 873 mm total length (TL) (545 mm TL median) and from 3 to 19 yr (median age 5 yr). The red snapper from Texas ranged in size from 380 to 903 mm TL (755 mm TL median) and ranged in age from 3 to 53 yr (median age 11 yr). Based on the results of the pilot surveys, expanded longline surveys targeting red snapper were conducted in 2001 and 2002; these surveys yielded 86 snapper and 75 snapper, respectively. The 2001 snapper ranged from 427 to 950 mm TL (770 mm TL median) and from 3 to 37 yr (median age 12 yr). The 2002 snapper ranged from 409 to 950 mm TL (815 mm TL median) and from 4 to 44 yr (median age 13 yr). Twelve red snapper were captured in the eastern Gulf (east of the Mississippi River), and their ages ranged from 3 to 19 yr (median age 6 yr). The 232 red snapper that were caught in the western Gulf ranged in age from 3 to 53 yr (median age 12 yr). A difference in catch rates by depth was also noted with most red snapper captures occurring in the 55-92 m depth range

Self Gravitating Fundamental Strings

We study the configuration of a typical highly excited string as one slowly increases the string coupling. The dominant interactions are the long range dilaton and gravitational attraction. In four spacetime dimensions, the string slowly contracts from its initial (large) size until it approaches the string scale where it forms a black hole. In higher dimensions, the string stays large until the coupling reaches a critical value, and then it rapidly collapses to a black hole. The implications for the recently proposed correspondence principle are discussed.Comment: 20 pages, LaTe

Evolution of eukaryotic transcription : insights from the genome of Giardia lamblia

Author Posting. © Cold Spring Harbor Laboratory Press, 2004. This article is posted here by permission of Cold Spring Harbor Laboratory Press for personal use, not for redistribution. The definitive version was published in Genome Research 14 (2004): 1537-1547, doi:10.1101/gr.2256604.The Giardia lamblia genome sequencing project affords us a unique opportunity to conduct comparative analyses of core cellular systems between early and late-diverging eukaryotes on a genome-wide scale. We report a survey to identify canonical transcription components in Giardia, focusing on RNA polymerase (RNAP) subunits and transcription-initiation factors. Our survey revealed that Giardia contains homologs to 21 of the 28 polypeptides comprising eukaryal RNAPI, RNAPII, and RNAPIII; six of the seven RNAP subunits without giardial homologs are polymerase specific. Components of only four of the 12 general transcription initiation factors have giardial homologs. Surprisingly, giardial TATA-binding protein (TBP) is highly divergent with respect to archaeal and higher eukaryotic TBPs, and a giardial homolog of transcription factor IIB was not identified. We conclude that Giardia represents a transition during the evolution of eukaryal transcription systems, exhibiting a relatively complete set of RNAP subunits and a rudimentary basal initiation apparatus for each transcription system. Most class-specific RNAP subunits and basal initiation factors appear to have evolved after the divergence of Giardia from the main eukaryotic line of descent. Consequently, Giardia is predicted to be unique in many aspects of transcription initiation with respect to paradigms derived from studies in crown eukaryotes.This work was supported in part by NIH grant AI43273 to M.L.S., by NIH grant AI51089 to A.G.M, and DOE grant DE-FG02-01ER63201 to G.J.O. Additional support was provided by the G. Unger Vetlesen Foundation and LI-COR Biotechnology

Histone deacetylase 4 interacts with 53BP1 to mediate the DNA damage response

Anumber of proteins are recruited to nuclear foci upon exposure to double-strand DNA damage, including 53BP1 and Rad51, but the precise role of these DNA damage–induced foci remain unclear. Here we show in a variety of human cell lines that histone deacetylase (HDAC) 4 is recruited to foci with kinetics similar to, and colocalizes with, 53BP1 after exposure to agents causing double-stranded DNA breaks. HDAC4 foci gradually disappeared in repair-proficient cells but persisted in repair-deficient cell lines or cells irradiated with a lethal dose, suggesting that resolution of HDAC4 foci is linked to repair. Silencing of HDAC4 via RNA interference surprisingly also decreased levels of 53BP1 protein, abrogated the DNA damage–induced G2 delay, and radiosensitized HeLa cells. Our combined results suggest that HDAC4 is a critical component of the DNA damage response pathway that acts through 53BP1 and perhaps contributes in maintaining the G2 cell cycle checkpoint

Disease-modifying therapy prescription patterns in people with multiple sclerosis by age

BACKGROUND: Disease-modifying therapies (DMTs) for multiple sclerosis (MS) are approved for their ability to reduce disease activity, namely clinical relapses and signal changes on magnetic resonance imaging (MRI). Disease activity appears age dependent. Thus, the greatest benefit would be expected in younger people with MS (PwMS) whereas benefits in the elderly are uncertain. METHODS: Real-world data were obtained from PwMS from the North American Research Committee on Multiple Sclerosis (NARCOMS) registry and the US Department of Veterans Affairs Multiple Sclerosis Surveillance Registry (MSSR). RESULTS: 6948 PwMS were surveyed from NARCOMS, and the MSSR had 1719 participants. In younger adult PwMS 40-years old or less, 183 (61.4%) in NARCOMS and 179 (70.5%) in the MSSR were prescribed DMTs. Among PwMS over age 60, 1575 (40.1%) in NARCOMS and 239 (36.3%) in the MSSR were prescribed DMTs. More PwMS in the age group of 31-40 ( CONCLUSION: These findings suggest that DMTs are under-utilized in the younger population and continue to be commonly prescribed in the elderly. Broader access may explain the higher prescription rate of DMTs in US veterans

Prescribing competency assessment for Canadian medical students: a pilot evaluation

Background: The knowledge and ability to prescribe safely and effectively is a core competency for every graduating medical student. Our previous research suggested concerns about medical student prescribing abilities, and interest in a standardized assessment process. Methods: A multi-year cross-sectional study evaluating the feasibility, acceptability, and discriminative ability of an online prescribing competency assessment for final year Canadian medical students was conducted. Students at nine sites of four Ontario medical schools were invited to participate in an online one-hour exam of eight domains related to prescribing safely. Student feedback on perceived fairness, clarity, and ease of use formed the primary outcome. Exam performance and parity between schools were the secondary outcome.  Results: A total of 714 students completed the assessment during spring final review courses between 2016 and 2018. Student feedback was more favourable than not for appropriateness of content (53.5% agreement vs 18.3% disagreement), clarity of questions (65.5% agreement vs 11.6% disagreement), question layout and presentation (70.8% agreement vs 12.2% disagreement), and ease of use of online interface (67.1% agreement vs 13.6% disagreement). Few (23.6% believed their course work had prepared them for the assessment. Mean total exam score was 70.0% overall (SD 10.4%), with 47.6% scoring at or above the pass threshold of 70%. Conclusion: Our prescribing competency assessment proved feasible, acceptable, and discriminative, and indicated a need for better medical school training to improve prescribing competency. Further evaluation in a larger sample of medical schools is warranted