The Effects of Fish Trap Mesh Size on Reef Fish Catch off Southeastern Florida

Catch and mesh selectivity of wire-meshed fish traps were tested for eleven different mesh sizes ranging from 13 X 13 mm (0.5 x 0.5") to 76 x 152 mm (3 X 6"). A total of 1,810 fish (757 kg) representing 85 species and 28 families were captured during 330 trap hauls off southeastern Florida from December 1986 to July 1988. Mesh size significantly affected catches. The 1.5" hexagonal mesh caught the most fish by number, weight, and value. Catches tended to decline as meshes got smaller or larger. Individual fish size increased with larger meshes. Laboratory mesh retention experiments showed relationships between mesh shape and size and individual retention for snapper (Lutjanidae), grouper (Serranidae), jack (Carangidae), porgy (Sparidae), and surgeonfish (Acanthuridae). These relationships may be used to predict the effect of mesh sizes on catch rates. Because mesh size and shape greatly influenced catchability, regulating mesh size may provide a useful basis for managing the commercial trap fishery

Comparison of the Molecular Structures of Monovalent Cation Salets of N,N-Dimethyldithiocarbamate. Novel Synthesis and Crystal Structure of (Phi4)(S2CN(CH3)2)2H2O

Crystals of the tetraphenylphosphonium N,N-dimethyldithiocarbamate dihydrate (C₂₇H₃₀NO₂PS₂; F.W. = 495.6) are monoclinic; P2₁/n; a = 13.349(6), b = 20,968(6), c = 9.800(4) Å, β = 109.01(3)°; Z = 4; V = 2593.4(16) Å^3; Dₓ = 1.269 gcm- 3 . Data were collected at ambient temperature using MoKα radiation (λ = 0.71069 Å).F(000) = 1048, linear absorption coefficient, n = 2.80 cm- 1. The structure was solved by direct methods and subsequently refined by full matrix least squares techniques. Final R value = 0.064 for 1 61 0 reflections and 298 varied parameters. Due to the nature of the cation, interactions between the tetraphenylphosphonium group and the sulfur atoms of the anion are absent, unlike previous dimethyldithiocarbamate structures (Na+, Cs+, TI+). Intermolecular interactions between the waters of hydration and the anion are present

Dominant Nuclear Outflow Driving Mechanisms in Powerful Radio Galaxies

In order to identify the dominant nuclear outflow mechanisms in Active Galactic Nuclei, we have undertaken deep, high resolution observations of two compact radio sources (PKS 1549-79 and PKS 1345+12) with the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope. Not only are these targets known to have powerful emission line outflows, but they also contain all the potential drivers for the outflows: relativistic jets, quasar nuclei and starbursts. ACS allows the compact nature (<0.15") of these radio sources to be optically resolved for the first time. Through comparison with existing radio maps we have seen consistency in the nuclear position angles of both the optical emission line and radio data. There is no evidence for bi-conical emission line features on the large-scale and there is a divergance in the relative position angles of the optical and radio structure. This enables us to exclude starburst driven outflows. However, we are unable to clearly distinguish between radiative AGN wind driven outflows and outflows powered by relativistic radio jets. The small scale bi-conical features, indicative of such mechanisms could be below the resolution limit of ACS, especially if aligned close to the line of sight. In addition, there may be offsets between the radio and optical nuclei induced by heavy dust obscuration, nebular continuum or scattered light from the AGN.Comment: 9 pages, 8 figures, emulateapj, ApJ Accepte

A Student\u27s Perspective on the Utilization of Social Media for Scholarly Research

The research was conducted on the continuous advancements on the Airline Quality Rating (AQR) developed by Dr . Brent Bowen, and the benefactor of research from a student perspective . The general case study focus of this research is the AQR as it relates to the utilization of social media platforms, and thus having the ability to reach out to a broader worldwide presence . Media metrics consisting of social network platforms, and news releases to assist in broadening the viewership and utilization of research in meeting individuals needs in gaining qualitative and quantified information about the AQR . As a student researcher for the AQR research initiative, it has helped me grow exponentially through the utilization of applied research methods . Additionally, while writing towards a potential audience, it has enhanced my communication skills through the presentations to members of the conferences in which I have attended

The Future of Social Media Usage for Scholarly Research

The research method for this project – examining the dissemination of research artifacts through social media as well as the impact social media can have on scholarly research – originated with Dr. Brent Bowen of Embry-Riddle Aeronautical University at the Prescott, Arizona campus and Dr. Dean E. Headley of Wichita State University. Drs. Bowen and Headley introduced the Airline Quality Rating (AQR) in early 1991 as an objective method for comparing and scoring airline performance in areas deemed to be important for consumers. Scores are calculated by defining 15-elements in four major areas, focusing on airline performance and the significance the factors to consumers of air travel in a given calendar year. The report is a summary and evaluation of month-by-month ratings for U.S. airlines, based on domestic performance data which these companies are required to publish. The general case study focus of this research is the AQR as it relates to the news of the AQR’s release as disseminated through social media platforms, the subsequent utilization of and references to the research by social media users, and the global reach of social media. We will examine social media metrics, based on traditional news releases. These news releases, when amplified by social media platforms, assist in broadening the viewership and the utilization of research. The AQR’s Visibility Reports evaluate four aspects of online traffic - Total Pickup, Traffic flow, Audience, and Engagement. We will discuss how the Airline Quality Rating has helped to facilitate a worldwide discussion on U.S. airlines and domestic air travel within the U.S

Response to comment on "Human-specific gain of function in a developmental enhancer"

Duret and Galtier argue that human-specific sequence divergence and gain of function in the HACNS1 enhancer result from deleterious biased gene conversion (BGC) with no contribution from positive selection. We reinforce our previous conclusion by analyzing hypothesized BGC events genomewide and assessing the effect of recombination rates on human-accelerated conserved noncoding sequence ascertainment. We also provide evidence that AT → GC substitution bias can coexist with positive selection

Effects of Noise on Ecological Invasion Processes: Bacteriophage-mediated Competition in Bacteria

Pathogen-mediated competition, through which an invasive species carrying and transmitting a pathogen can be a superior competitor to a more vulnerable resident species, is one of the principle driving forces influencing biodiversity in nature. Using an experimental system of bacteriophage-mediated competition in bacterial populations and a deterministic model, we have shown in [Joo et al 2005] that the competitive advantage conferred by the phage depends only on the relative phage pathology and is independent of the initial phage concentration and other phage and host parameters such as the infection-causing contact rate, the spontaneous and infection-induced lysis rates, and the phage burst size. Here we investigate the effects of stochastic fluctuations on bacterial invasion facilitated by bacteriophage, and examine the validity of the deterministic approach. We use both numerical and analytical methods of stochastic processes to identify the source of noise and assess its magnitude. We show that the conclusions obtained from the deterministic model are robust against stochastic fluctuations, yet deviations become prominently large when the phage are more pathological to the invading bacterial strain.Comment: 39 pages, 7 figure