Growth and claw regeneration of the stone crab, Menippe mercenaria

Savage, T. and J.R. Sullivan. 1978. Growth and Claw Regeneration of the Stone Crab, Menippe mercenaria. Fla. Mar. Res. Publ. No. 32.23 pp. Laboratory-maintained and feral crabs were observed for incremental carapace width and major and minor claw growth. Morphometric relationships for male and female carapace width against length and carapace width against major and minor claw sizes were derived. Only slopes of carapace width us. female major and male minor claws were not significantly different at the 95% confidence level. Feral normal male incremental growth exceeded that of normal females for all parameters. Normal laboratory females possessed greater average carapace width growth but less claw growth than did their male counterparts. All laboratory growth was more uniform but incrementally smaller than corresponding field growth. A hypothetical growth plot constructed from incremental growth of several crabs indicated ages at attainment of sexual maturity and legal size to be 10 and 30 months. A pictorial description of stone crab claw regeneration is presented. Minor claws realized greater regeneration after one and two molts (73.5% and 96.5% of pre-autotomized sizes) than did major claws (68.6% and 89.0%). Intermolt interval of laboratory crabs increased with larger carapace width sizes. Claw loss shortened or lengthened duration of the intermolt period depending upon whether the claw was removed shortly after a molt or later in the cycle. (Document has 27 pages.

Dancing with loneliness in later life: A pilot study mapping seasonal variations

Temporal variations in loneliness at the individual and population level have long been reported in longitudinal studies. Although the evidence is limited due to methodological distinctions among studies, we broadly know that loneliness as one ages is a dynamic experience with people becoming more or less lonely or staying the same over time. There is, however, less evidence to understand individual variations in loneliness over shorter periods of time. This paper reports on one element of a small mixed method pilot study to investigate seasonal variations in loneliness over the course of one year and to test the effectiveness of tools used to collect data at repeated short intervals. Our findings confirm that loneliness is dynamic even over shorter periods of time with participants reporting to be lonelier in the evenings, weekends and spring-summer period. Data measures were at times problematic due to language and/or interpretation and reinforce the relevance of reviewing the more common approaches to studying loneliness to more effectively capture the complex and individual nature of the experience.Brunel University Londo

Doxycycline alters metabolism and proliferation of human cell lines.

The tetracycline antibiotics are widely used in biomedical research as mediators of inducible gene expression systems. Despite many known effects of tetracyclines on mammalian cells-including inhibition of the mitochondrial ribosome-there have been few reports on potential off-target effects at concentrations commonly used in inducible systems. Here, we report that in human cell lines, commonly used concentrations of doxycycline change gene expression patterns and concomitantly shift metabolism towards a more glycolytic phenotype, evidenced by increased lactate secretion and reduced oxygen consumption. We also show that these concentrations are sufficient to slow proliferation. These findings suggest that researchers using doxycycline in inducible expression systems should design appropriate controls to account for potential confounding effects of the drug on cellular metabolism

X-rays from Microstructured Targets Heated by Femtosecond Lasers

We have demonstrated efficient conversion of ultrashort-pulse laser energy to x rays with energies above 1 keV, using laser-produced plasmas generated on a variety of microstructured surfaces. Lithographically produced grating targets generated 0.1 mJ of kilo-electron-volt x rays, and porous gold and aluminum targets emitted 1 mJ. This represents an improvement of a factor of 100 over flat targets. The K-shell emission spectrum of porous aluminum was composed primarily of heliumlike spectral lines

Subpicosecond Thomson Scattering Measurements of Optically Ionized Helium Plasmas

We present the first subpicosecond time-resolved temperature measurements of plasmas produced by high-intensity optical ionization. Thomson scattering is used to measure electron and ion temperatures of helium plasmas created by 125 fs, 800 nm laser pulses focused to an intensity of 2 × 1017 W/cm2. We find that the electron temperature is accurately predicted by a tunneling ionization model. The measured ion temperature is consistent with direct heating by the laser pulse

Spectral Models for Early Time SN 2011fe Observations

We use observed UV through near IR spectra to examine whether SN 2011fe can be understood in the framework of Branch-normal SNe Ia and to examine its individual peculiarities. As a benchmark, we use a delayed-detonation model with a progenitor metallicity of Z_solar/20. We study the sensitivity of features to variations in progenitor metallicity, the outer density profile, and the distribution of radioactive nickel. The effect of metallicity variations in the progenitor have a relatively small effect on the synthetic spectra. We also find that the abundance stratification of SN 2011fe resembles closely that of a delayed detonation model with a transition density that has been fit to other Branch-normal Type Ia supernovae. At early times, the model photosphere is formed in material with velocities that are too high, indicating that the photosphere recedes too slowly or that SN 2011fe has a lower specific energy in the outer ~0.1 M_sun than does the model. We discuss several explanations for the discrepancies. Finally, we examine variations in both the spectral energy distribution and in the colors due to variations in the progenitor metallicity, which suggests that colors are only weak indicators for the progenitor metallicity, in the particular explosion model that we have studied. We do find that the flux in the U band is significantly higher at maximum light in the solar metallicity model than in the lower metallicity model and the lower metallicity model much better matches the observed spectrum.Comment: 9 pages, 14 figures, MNRAS, in press, fixed typ

Transient analysis mode participation for modal survey target mode selection using MSC/NASTRAN DMAP

Many methods have been developed to aid analysts in identifying component modes which contribute significantly to component responses. These modes, typically targeted for dynamic model correlation via a modal survey, are known as target modes. Most methods used to identify target modes are based on component global dynamic behavior. It is sometimes unclear if these methods identify all modes contributing to responses important to the analyst. These responses are usually those in areas of hardware design concerns. One method used to check the completeness of target mode sets and identify modes contributing significantly to important component responses is mode participation. With this method, the participation of component modes in dynamic responses is quantified. Those modes which have high participation are likely modal survey target modes. Mode participation is most beneficial when it is used with responses from analyses simulating actual flight events. For spacecraft, these responses are generated via a structural dynamic coupled loads analysis. Using MSC/NASTRAN DMAP, a method has been developed for calculating mode participation based on transient coupled loads analysis results. The algorithm has been implemented to be compatible with an existing coupled loads methodology and has been used successfully to develop a set of modal survey target modes

Professional Organizations and Healthcare Industry Support: Ethical Conflict?

A good deal of attention has been recently focused on the presumed advertising excesses of the healthcare industry in its promotion techniques to healthcare professionals, whether through offering gratuities such as gifts, honoraria, or travel support2-6 or through deception. Two basic concerns have been expressed: Does the acceptance of gratuities bias the recipient, tainting his or her responsibilities as the patient's agent? Does acceptance of the gratuity by the healthcare professional contribute to the high cost of healthcare products? The California Society of Hospital Pharmacists was recently asked by its members to formulate a policy for an appropriate relationship between the Society and the healthcare industry, addressing these concerns. In formulating its policy, it became clear that the Society depended on healthcare industry support, gathered through journal advertising, fees for booths at its various educational events, and grants for speaker