Movements of radio-tagged manatees in Tampa Bay and along Florida’s west coast, 1991–1996

Manatees wintering in Tampa Bay, Florida, were captured and fitted with satellite- and radio-telemetry equipment during a research project conducted from 1991 to 1996. Forty-four manatees were tagged after their capture in Tampa Bay; an additional 15 animals were tagged at other west coast locations. Locations of individual animals were estimated via satellite up to eight times per day, and observations of manatee locations were made in the field one or more times per week. These data were entered into a relational database and converted to a format accessible as points within a geographic information system (GIS). Seasonal densities of satellite locations were mapped for 33 manatees tagged in Tampa Bay. Within the bay, manatees aggregated at or near warm-water locations during winter. In other seasons, manatee density was highest in areas that had abundant sea grass and were close to fresh-water sources. Sequential data points for individual manatees were transformed into probable travel routes by using a GIS-based cost-path analysis. A map was created for each tagged manatee depicting estimated travel paths, and detailed descriptive information summarized major movements, tagging history, and physical characteristics. The travel patterns of male manatees were characterized by almost continual movement, often along predictable routes or circuits. Most males larger than 265 cm ranged 100 km or more away from Tampa Bay during non-winter months whereas smaller males remained in or near the bay. As males matured, their travel ranges appeared to expand. Female manatees used two general movement patterns. Small females and females with calves would use specific areas within a day’s travel of the warm-water sources for extended periods before moving to similar nearby areas for protracted stays. Females without calves and females longer than 330 cm with calves added long migrations between areas chosen for foraging.The ranges of some females extended south to Charlotte Harbor,the Caloosahatchee River,and the Everglades. Two tagged females traveled from Florida’s west coast to the east coast: one traveled south around the peninsula, and the other apparently moved east through Lake Okeechobee and the lock system

Meson Mass Splittings in the Nonrelativistic Model

Mass splittings between isodoublet meson pairs and between $0^{-}$ and $1^{-}$ mesons of the same valence quark content are computed in a detailed nonrelativistic model. The field theoretic expressions for such splittings are shown to reduce to kinematic and Breit-Fermi terms in the nonrelativistic limit. Algebraic results thus obtained are applied to the specific case of the linear-plus-Coulomb potential, with resultant numbers compared to experiment.Comment: 29 pages with 2 tables and 4 figures, LBL-32872 and UCB-PTH-92/3

Non-perturbative Gluons and Pseudoscalar Mesons in Baryon Spectroscopy

We study baryon spectroscopy including the effects of pseudoscalar meson exchange and one gluon exchange potentials between quarks, governed by $\alpha_s$. The non-perturbative, hyperspherical method calculations show that one can obtain a good description of the data by using a quark-meson coupling constant that is compatible with the measured pion-nucleon coupling constant, and a reasonably small value of $\alpha_s$.Comment: 12 pages; Submitted to Phys. Rev. C. Rapid Communication

Economists' Statement on U.S. Broadband Policy

In this statement, a group of economists assembled by the AEI-Brookings Joint Center makes the following two recommendations to improve the competitive provision of broadband services. First, Congress should eliminate local franchising regulations, which serve as a barrier to new entry. Second, Congress and the Federal Communications Commission should make more spectrum available to private parties and allow them to use it as they see fit or trade their licenses in the market, so that spectrum will go to its highest-valued uses.Technology and Industry

Identification and Classification of Conserved RNA Secondary Structures in the Human Genome

The discoveries of microRNAs and riboswitches, among others, have shown functional RNAs to be biologically more important and genomically more prevalent than previously anticipated. We have developed a general comparative genomics method based on phylogenetic stochastic context-free grammars for identifying functional RNAs encoded in the human genome and used it to survey an eight-way genome-wide alignment of the human, chimpanzee, mouse, rat, dog, chicken, zebra-fish, and puffer-fish genomes for deeply conserved functional RNAs. At a loose threshold for acceptance, this search resulted in a set of 48,479 candidate RNA structures. This screen finds a large number of known functional RNAs, including 195 miRNAs, 62 histone 3′UTR stem loops, and various types of known genetic recoding elements. Among the highest-scoring new predictions are 169 new miRNA candidates, as well as new candidate selenocysteine insertion sites, RNA editing hairpins, RNAs involved in transcript auto regulation, and many folds that form singletons or small functional RNA families of completely unknown function. While the rate of false positives in the overall set is difficult to estimate and is likely to be substantial, the results nevertheless provide evidence for many new human functional RNAs and present specific predictions to facilitate their further characterization

Разработка интерактивной моделирующей системы технологии низкотемпературной сепарации газа

We present a study of J ψ meson production in collisions of 26.7 GeV electrons with 820 GeV protons, performed with the H1-detector at the HERA collider at DESY. The J ψ mesons are detected via their leptonic decays both to electrons and muons. Requiring exactly two particles in the detector, a cross section of σ(ep → J ψ X) = (8.8±2.0±2.2) nb is determined for 30 GeV ≤ W γp ≤ 180 GeV and Q 2 ≲ 4 GeV 2 . Using the flux of quasi-real photons with Q 2 ≲ 4 GeV 2 , a total production cross section of σ ( γp → J / ψX ) = (56±13±14) nb is derived at an average W γp =90 GeV. The distribution of the squared momentum transfer t from the proton to the J ψ can be fitted using an exponential exp(− b ∥ t ∥) below a ∥ t ∥ of 0.75 GeV 2 yielding a slope parameter of b = (4.7±1.9) GeV −2