Dietary Diversity and Overlap Between Two Subspecies of Spadefoot Toads (Scaphiopus holbrookii holbrookii and S. h. hurterii) in Arkansas

The food habits of adult spadefoot toads (Scaphiopus h. holbrookii and S. h. hurterii) collected in Arkansas were exam ined during this study. Thirty-six adult S. h. holbrookii (29 males and 7 females) and 48 adult S. h. hurterii (23 males and 2 females) were necropsied. Most specimens were collected over a 10-year span oftime (1985-94). Alltoads were taken from breeding aggregations which were visited periodically inany given year (frommid-February to late April).Prey items wer found in the stomachs of 13 (36.1%) of the S. h. holbrookii and 23 (48.0%) ofthe S. h. hurterii. Scaphiopus h. holbrookii and h. hurterii have similar diets. Both subspecies feed on a variety of ground-dwelling arthropods with 19 taxa being ident tied to the order or the familiallevel. The data suggested that there was considerable dietary overlap based upon the fa that beetles and catepillars were the primary food items. The presence ofonly one aquatic insect inall the stomachs inc cated that the toads restrict their feeding activity after arriving at breeding ponds. Additional seasonal collections ai required to better understand dietary diversity

A note on the calculation of the effective range

The closed form of the first order non-linear differential equation that is satisfied by the effective range within the variable phase formulation of scattering theory is discussed. It is shown that the conventional method of determining the effective range, by fitting a numerical solution of the Schr\"odinger equation to known asymptotic boundary conditions, can be modified to include the first order contribution of a long range interaction.Comment: 4 page

Marine fish may be biochemically constrained from inhabiting the deepest ocean depths

No fish have been found in the deepest 25% of the ocean (8,400-11,000 m). This apparent absence has been attributed to hydrostatic pressure, although direct evidence is wanting because of the lack of deepest-living species to study. The common osmolyte trimethylamine N-oxide (TMAO) stabilizes proteins against pressure and increases with depth, going from 40 to 261 mmol/kg in teleost fishes from 0 to 4,850 m. TMAO accumulation with depth results in increasing internal osmolality (typically 350 mOsmol/kg in shallow species compared with seawater\u27s 1,100 mOsmol/kg). Preliminary extrapolation of osmolalities of predicted isosmotic state at 8,000-8,500 m may indicate a possible physiological limit, as greater depths would require reversal of osmotic gradients and, thus, osmoregulatory systems. We tested this prediction by capturing five of the second-deepest known fish, the hadal snailfish (Notoliparis kermadecensis; Liparidae), from 7,000 m in the Kermadec Trench. We found theirmuscles to have a TMAOcontent of 386 ± 18 mmol/kg and osmolality of 991 ± 22 mOsmol/kg. These data fit previous extrapolations and, combined with new osmolalities from bathyal and abyssal fishes, predict isosmotic state at 8,200 m. This is previously unidentified evidence that biochemistry could constrain the depth of a large, complex taxonomic group

The variable phase method used to calculate and correct scattering lengths

It is shown that the scattering length can be obtained by solving a Riccati equation derived from variable phase theory. Two methods of solving it are presented. The equation is used to predict how long-range interactions influence the scattering length, and upper and lower bounds on the scattering length are determined. The predictions are compared with others and it is shown how they may be obtained from secular perturbation theory.Comment: 7 pages including 3 figure

Planning, Implementing, and Evaluating a Program to Address the Oral Health Needs of Aboriginal Children in Port Augusta, Australia

Aboriginal Australian children experience profound oral health disparities relative to their non-Aboriginal counterparts. In response to community concerns regarding Aboriginal child oral health in the regional town of Port Augusta, South Australia, a child dental health service was established within a Community Controlled Aboriginal Health Service. A partnership approach was employed with the key aims of (1) quantifying rates of dental service utilisation, (2) identifying factors influencing participation, and (3) planning and establishing a program for delivery of Aboriginal children's dental services that would increase participation and adapt to community needs. In planning the program, levels of participation were quantified and key issues identified through semistructured interviews. After 3.5 years, the participation rate for dental care among the target population increased from 53 to 70 percent. Key areas were identified to encourage further improvements and ensure sustainability in Aboriginal child oral health in this regional location

Cold Collision Frequency Shift of the 1S-2S Transition in Hydrogen

We have observed the cold collision frequency shift of the 1S-2S transition in trapped spin-polarized atomic hydrogen. We find $\Delta \nu_{1S-2S} = -3.8(8)\times 10^{-10} n Hz cm^3$, where $n$ is the sample density. From this we derive the 1S-2S s-wave triplet scattering length, $a_{1S-2S}=-1.4(3)$ nm, which is in fair agreement with a recent calculation. The shift provides a valuable probe of the distribution of densities in a trapped sample.Comment: Accepted for publication in PRL, 9 pages, 4 PostScript figures, ReVTeX. Updated connection of our measurement to theoretical wor