Molecular phylogeny of brachiopods and phoronids based on nuclear-encoded small subunit ribosomal RNA gene sequences

Brachiopod and phoronid phylogeny is inferred from SSU rDNA sequences of 28 articulate and nine inarticulate brachiopods, three phoronids, two ectoprocts and various outgroups, using gene trees reconstructed by weighted parsimony, distance and maximum likelihood methods. Of these sequences, 33 from brachiopods, two from phoronids and one each from an ectoproct and a priapulan are newly determined. The brachiopod sequences belong to 31 different genera and thus survey about 10% of extant genus-level diversity. Sequences determined in different laboratories and those from closely related taxa agree well, but evidence is presented suggesting that one published phoronid sequence (GenBank accession UO12648) is a brachiopod-phoronid chimaera, and this sequence is excluded from the analyses. The chiton, Acanthopleura, is identified as the phenetically proximal outgroup; other selected outgroups were chosen to allow comparison with recent, non-molecular analyses of brachiopod phylogeny. The different outgroups and methods of phylogenetic reconstruction lead to similar results, with differences mainly in the resolution of weakly supported ancient and recent nodes, including the divergence of inarticulate brachiopod sub-phyla, the position of the rhynchonellids in relation to long- and short-looped articulate brachiopod clades and the relationships of some articulate brachiopod genera and species. Attention is drawn to the problem presented by nodes that are strongly supported by non-molecular evidence but receive only low bootstrap resampling support. Overall, the gene trees agree with morphology-based brachiopod taxonomy, but novel relationships are tentatively suggested for thecideidine and megathyrid brachiopods. Articulate brachiopods are found to be monophyletic in all reconstructions, but monophyly of inarticulate brachiopods and the possible inclusion of phoronids in the inarticulate brachiopod clade are less strongly established. Phoronids are clearly excluded from a sister-group relationship with articulate brachiopods, this proposed relationship being due to the rejected, chimaeric sequence (GenBank UO12648). Lineage relative rate tests show no heterogeneity of evolutionary rate among articulate brachiopod sequences, but indicate that inarticulate brachiopod plus phoronid sequences evolve somewhat more slowly. Both brachiopods and phoronids evolve slowly by comparison with other invertebrates. A number of palaeontologically dated times of earliest appearance are used to make upper and lower estimates of the global rate of brachiopod SSU rDNA evolution, and these estimates are used to infer the likely divergence times of other nodes in the gene tree. There is reasonable agreement between most inferred molecular and palaeontological ages. The estimated rates of SSU rDNA sequence evolution suggest that the last common ancestor of brachiopods, chitons and other protostome invertebrates (Lophotrochozoa and Ecdysozoa) lived deep in Precambrian time. Results of this first DNA-based, taxonomically representative analysis of brachiopod phylogeny are in broad agreement with current morphology-based classification and systematics and are largely consistent with the hypothesis that brachiopod shell ontogeny and morphology are a good guide to phylogeny

Comparative study of visual performance with tinted soft contact lenses vs. clear soft contact lenses and tinted spectacles under bright outdoor conditions; Phase II

Background: Research has clearly shown the advantages of performance tinted CL wear with regard to various measures of objective and subjective responses under various lighting conditions. The current study expanded upon these results. Methods: Subjects were 38 non-presbyopic emmetropes or slight ametropes with distance Snellen acuity of 20/20 or better while wearing -0.50 D spherical Acuvue 2 CLs. Measurements of 6m tachistoscopic stereoacuity and variable distance timed and tachistoscopic texture gradient recognition were obtained with subjects wearing clear CLs, tinted spectacles, and SportSight CLs. Lens modality and test sequence were randomized. Results: Stereoacuity results showed no statistically significant difference in stereolocalization when subjects were wearing clear CLs, SportSight CLs, or tinted spectacles. Texture gradient results using timed and tachistoscopic presentations demonstrated that it was more difficult for subjects to correctly identify the seam orientation at farther distances than nearer distances, and that subjects took more time to try to identify distant target orientation versus near target orientation. In addition, tachistoscopic presentations were not found to be significant with regard to correctness of responses at any distance with any lens modality. Subjective data indicated more physical comfort with either CL modality instead of tinted spectacles. SportSight CLs were also found to be the most visually comfortable modality, followed by tinted spectacles and then clear CLs. Furthermore, a general trend indicated that subjects felt they were able to perform best while wearing the SportSight CLs. This may partially be due to the fact that subjects noted fewer perceptions of stray light with SportSight CLs than with the other modalities. Likewise, subjects reported an equal number of perceived reflections while wearing SportSight CLs and clear CLs but significantly more while wearing tinted spectacles. Conclusion: Objective findings demonstrated that SportSight CLs provide similar performance with regard to distance depth perception and texture gradient recognition to tinted spectacles. Subjective data indicate that visual comfort of the SportSight CLs was superior to tinted spectacles and clear CLs. Additionally, a trend in subjective data demonstrated that the subjects perceived improved performance on the tests while wearing the SportSight CLs

A study investigating a season\u27s baseball performance while wearing SportSight soft contact lenses

Background: The use of spectacles with colored lenses in sports is well known. Athletes have worn such colored lenses in an attempt to enhance their performance for a number of years with promising results. The integration of wavelength specific filters into contact lenses may provide significant performance enhancement as well as the visual advantages usually afforded by contact lenses relative to spectacles. Methods: A small group (N=5) of collegiate baseball players were fitted with SportSight soft contact lenses and were asked to wear them during practices and games for half of a season. The players\u27 batting and fielding statistics from the first and second halves of the season were compared to each other and to those of non-participating team members. All of the subjects were existing soft contact lens wearers. Results: The test group demonstrated dramatic improvements in batting statistics while wearing the SportSight lenses. Their percentage of statistical improvement in each category far surpassed that of non-participating team members. Conclusion: The results of this pilot study imply that wearing SportSight soft contact lenses yields marked performance enhancement for baseball players. Future studies involving larger subject pools are warranted to thoroughly evaluate the possible statistical significance of these findings

Assessing Depression-Related Mental Health Literacy among Young Adults

Background and Purpose: Young adults who are 18 to 25 years old have the highest prevalence of depression (10.9%). Depression is a risk factor for suicide. Mental health literacy (MHL) is a key component in assessing recognition and help-seeking for depression with suicidal ideation. This study investigated MHL as it relates to help-seeking for depression with suicidal ideation. Methods: A crosssectional survey design was used. Participants were young adults (n= 430, ages 18 to 24 years old) who lived, worked, and/or attended school in San Francisco, California. Reavley and colleagues’ MHL survey was modified and made available in English, Spanish, and Chinese. Results: Several background factors were positively, though weakly, correlated to MHL, based on the r coefficient. Significant factors were: being female [r=.12,

Profiling the molecular destruction rates of temperature and humidity as well as the turbulent kinetic energy dissipation in the convective boundary layer

A simultaneous deployment of Doppler, temperature, and water-vapor lidars is able to provide profiles of molecular destruction rates and turbulent kinetic energy (TKE) dissipation in the convective boundary layer (CBL). Horizontal wind profiles and profiles of vertical wind, temperature, and moisture fluctuations are combined, and transversal temporal autocovariance functions (ACFs) are determined for deriving the dissipation and molecular destruction rates. These are fundamental loss terms in the TKE as well as the potential temperature and mixing ratio variance equations. These ACFs are fitted to their theoretical shapes and coefficients in the inertial subrange. Error bars are estimated by a propagation of noise errors. Sophisticated analyses of the ACFs are performed in order to choose the correct range of lags of the fits for fitting their theoretical shapes in the inertial subrange as well as for minimizing systematic errors due to temporal and spatial averaging and micro- and mesoscale circulations. We demonstrate that we achieve very consistent results of the derived profiles of turbulent variables regardless of whether 1 or 10 s time resolutions are used. We also show that the temporal and spatial length scales of the fluctuations in vertical wind, moisture, and potential temperature are similar with a spatial integral scale of ≈160 m at least in the mixed layer (ML). The profiles of the molecular destruction rates show a maximum in the interfacial layer (IL) and reach values of ϵm≃7×10-4 g2 kg−2 s−1 for mixing ratio and ϵθ≃1.6×10-3 K2 s−1 for potential temperature. In contrast, the maximum of the TKE dissipation is reached in the ML and amounts to ≃10-2 m2 s−3. We also demonstrate that the vertical wind ACF coefficient kw∝w′2‾ and the TKE dissipation ϵ∝w′2‾3/2. For the molecular destruction rates, we show that ϵm∝m′2‾w′2‾1/2 and ϵθ∝θ′2‾w′2‾1/2. These equations can be used for parameterizations of ϵ, ϵm, and ϵθ. All noise error bars are derived by error propagation and are small enough to compare the results with previous observations and large-eddy simulations. The results agree well with previous observations but show more detailed structures in the IL. Consequently, the synergy resulting from this new combination of active remote sensors enables the profiling of turbulent variables such as integral scales, variances, TKE dissipation, and the molecular destruction rates as well as deriving relationships between them. The results can be used for the parameterization of turbulent variables, TKE budget analyses, and the verification of large-eddy simulations.</p

DETERMINATION OF TYPES OF INDIVIDUALS IN APHIDS, ROTIFERS AND CLADOCERA 1

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72827/1/j.1469-185X.1929.tb00888.x.pd

The macro-and micro-fossil record of the Cambrian priapulid Ottoia

The stem-group priapulid Ottoia Walcott, 1911, is the most abundant worm in the mid-Cambrian Burgess Shale, but has not been unambiguously demonstrated elsewhere. High-resolution electron and optical microscopy of macroscopic Burgess Shale specimens reveals the detailed anatomy of its robust hooks, spines and pharyngeal teeth, establishing the presence of two species: Ottoia prolifica Walcott, 1911, and Ottoia tricuspida sp. nov. Direct comparison of these sclerotized elements with a suite of shale-hosted mid-to-late Cambrian microfossils extends the range of ottoiid priapulids throughout the middle to upper Cambrian strata of the Western Canada Sedimentary Basin. Ottoiid priapulids represented an important component of Cambrian ecosystems: they occur in a range of lithologies and thrived in shallow water as well as in the deep-water setting of the Burgess Shale. A wider survey of Burgess Shale macrofossils reveals specific characters that diagnose priapulid sclerites more generally, establishing the affinity of a wide range of Small Carbonaceous Fossils and demonstrating the prominent role of priapulids in Cambrian seas

Observation of the Dynamic Beta Effect at CESR with CLEO

Using the silicon strip detector of the CLEO experiment operating at the Cornell Electron-positron Storage Ring (CESR), we have observed that the horizontal size of the luminous region decreases in the presence of the beam-beam interaction from what is expected without the beam-beam interaction. The dependence on the bunch current agrees with the prediction of the dynamic beta effect. This is the first direct observation of the effect.Comment: 9 page uuencoded postscript file, postscritp file also available through http://w4.lns.cornell.edu/public/CLNS, submitted to Phys. Rev.