Status of Acropora palmata Populations off the Coast of South Caicos, Turks and Caicos Islands

This study is the first detailed assessment of A. palmata populations of the Turks and Caicos Islands. A total of 203 individual colonies and 62 thickets were tagged on five shallow reefs. Depth, percentages of living tissue, recent mortality and old skeleton were estimated. Presence of disease and predatory snails was noted, and disease spread and grazing rates of the snails estimated. Colonies were found in depths of 0.2 - 4 m. Living tissue for individual colonies (75.9% ± 2.2 SE) was significantly greater than for thickets (58.6% ± 3.6) and in both cases exceeded old skeleton (individuals: 22.7% ± 2.1 SE, thickets: 38.0% ± 3.4 SE). Percentage of recent mortality was very low (individuals: 1.3% ± 0.3 SE, thickets: 3.4% ± 0.7%). We found WBD (n = 2), white pox disease a (WPDa) (n = 7) and white pox disease b (WPDb) (n = 14) with greatly varying spreading rates. The WBD infected colonies showed an atypical spread from the top of the branch towards the base. Coralliophila abbreviata and C. caribaea affected 3 .7 54.7% of the populations (grazing rate: 4.29 cm 2 /day/snail ± 1.16 SE). South Caicos’ A. palmata populations are still in good condition, though increasing human disturbances combined with disease and predatory snails may threaten these populations

Environmental controls on daytime net community calcification on a Red Sea reef flat

Coral growth and carbonate accumulation form the foundation of the coral reef ecosystem. Changes in environmental conditions due to coastal development, climate change, and ocean acidification may pose a threat to net carbonate production in the near future. Controlled laboratory studies demonstrate that calcification by corals and coralline algae is sensitive to changes in aragonite saturation state (Ωa), as well as temperature, light, and nutrition. Studies also show that the dissolution rate of carbonate substrates is impacted by changes in carbonate chemistry. The sensitivity of coral reefs to these parameters must be confirmed and quantified in the natural environment in order to predict how coral reefs will respond to local and global changes, particularly ocean acidification. We estimated the daytime hourly net community metabolic rates, both net community calcification (NCC) and net community productivity (NCP), at Sheltered Reef, an offshore platform reef in the central Red Sea. Average NCC was 8 ± 3 mmol m[superscript −2] h[superscript −1] in December 2010 and 11 ± 1 mmol m[superscript −2] h[superscript −1] in May 2011, and NCP was 21 ± 7 mmol m[superscript −2] h[superscript −1] in December 2010 and 44 ± 4 mmol m[superscript −2] h[superscript −1] in May 2011. We also monitored a suite of physical and chemical properties to help relate the rates at Sheltered Reef to published rates from other sites. While previous research shows that short-term field studies investigating the NCC–Ωa relationship have differing results due to confounding factors, it is important to continue estimating NCC in different places, seasons, and years, in order to monitor changes in NCC versus Ω in space and time, and to ultimately resolve a broader understanding of this relationship.National Science Foundation (U.S.) (Graduate Research Fellowship

Promoting sustainability in quality improvement: an evaluation of a web-based continuing education program in blood pressure measurement.

BACKGROUND: The accuracy of blood pressure measurement is variable in office-based settings. Even when staff training programs are effective, knowledge and skills decay over time, supporting the need for ongoing staff training. We evaluated whether a web-based continuing education program in blood pressure measurement reinforced knowledge and skills among clinical staff and promoted sustainability of an existing quality improvement program. METHODS: Medical assistants and nurses at six primary care clinics within a health system enrolled in a 30-min online educational program designed to refresh their knowledge of blood pressure measurement. A 20-question pre- and post-intervention survey addressed learners\u27 knowledge and attitudes. Direct observation of blood pressure measurement technique before and after the intervention was performed. Differences in responses to pre- and post-module knowledge and attitudes questions and in observation data were analyzed using chi-square tests and simple logistic regression. RESULTS: All 88 clinical staff members participated in the program and completed the evaluation survey. Participants answered 80.6% of questions correctly before the module and 93.4% afterwards (p \u3c 0.01). Scores improved significantly among staff from all job types. Licensed practical nurses and staff who had been in their current job at least a year were more likely to answer questions correctly than registered nurses and those in their current job less than a year. Attitudes toward correct blood pressure measurement were high at baseline and did not improve significantly. Prior to the intervention, staff adhered to 9 of 18 elements of the recommended technique during at least 90% of observations. Following the program, staff was more likely to explain the protocol, provide a rest period, measure an average blood pressure, and record the average blood pressure, but less likely to measure blood pressure with the arm at heart level and use the right arm. CONCLUSIONS: We designed, implemented, and evaluated a web-based educational program to improve knowledge, skills, and attitudes in blood pressure measurement and use of an automated device among nurses and medical assistants in ambulatory care. The program reinforced knowledge related to recommended blood pressure measurement technique. TRIAL REGISTRATION: Retrospectively registered with ClincalTrials.gov on March 22, 2012; registration number NCT01566864

Quantitative analysis of cell types during growth and morphogenesis in Hydra

Tissue maceration was used to determine the absolute number and the distribution of cell types in Hydra. It was shown that the total number of cells per animal as well as the distribution of cells vary depending on temperature, feeding conditions, and state of growth. During head and foot regeneration and during budding the first detectable change in the cell distribution is an increase in the number of nerve cells at the site of morphogenesis. These results and the finding that nerve cells are most concentrated in the head region, diminishing in density down the body column, are discussed in relation to tissue polarity

Detectibility of Mixed Unburnt C+O in Type Ia Supernova Spectra

Motivated by recent 3-D calculations of the explosion of Type Ia supernova via a pure deflagration we calculate the observed spectra at 15-25 days past maximum light of a parameterized model which has a considerable fraction of unburnt C+O in the central regions. Rather than attempting a self consistent 3-D calculation, which is beyond the scope of current computer codes, we modify the composition structure of the 1-D deflagration model W7. In our exploratory parameterized calculations, we find that a central concentration of C+O is not ruled out by observations for the epochs we study. We briefly examine whether nebular phase spectra could be incompatible with observations.Comment: 12 pages, 3 figures ApJ Letters, May 1, 2003, in pres

Ordered and disordered phospholipid domains coexist in membranes containing the calcium pump protein of sarcoplasmic reticulum.

Data are presented that lead to an alternative model for the organization and molecular dynamics of lipid molecules near the Ca2+-stimulated, Mg2+-dependent adenosinetriphosphatase (Ca2+-ATPase; ATP phosphohydrolase, EC 3.6.1.3) of sarcoplasmic reticulum. Measurements of the steady-state fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene in progressively delipidated sarcoplasmic reticulum membranes have been quantitatively interpreted in terms of a layer of lipid of high anisotropy (the lipid annulus) coexisting with lipid layers of very low anisotropy. In addition, the Ca2+-ATPase has been reconstituted into pure 1,2-dipentadecanoyl 3-sn-phosphatidylcholine membranes over a range of lipid-to-protein ratios. High-sensitivity differential scanning calorimetry has demonstrated that roughly 30 lipid molecules per Ca2+-ATPase molecule (annular lipids) fail to undergo a calorimetrically detectable phase transition in the temperature range 4-44 degrees C. Roughly 100 lipid molecules beyond the annulus undergo a detectable phase transition at a temperature below the phase transition of pure lipid and with an enthalpy change [4.2 kcal/mol (1 kcal = 4.18 kJ)] about half that observed for pure lipid vesicles (7.7-7.8 kcal/mol). We propose that both the fluorometric and calorimetric data are consistent with a model in which a motionally inhibited lipid annulus is surrounded by a more extensive region of disrupted lipid packing order, which we have called the secondary lipid domain

Gravitational Waves from Core Collapse Supernovae

We present the gravitational wave signatures for a suite of axisymmetric core collapse supernova models with progenitors masses between 12 and 25 solar masses. These models are distinguished by the fact they explode and contain essential physics (in particular, multi-frequency neutrino transport and general relativity) needed for a more realistic description. Thus, we are able to compute complete waveforms (i.e., through explosion) based on non-parameterized, first-principles models. This is essential if the waveform amplitudes and time scales are to be computed more precisely. Fourier decomposition shows that the gravitational wave signals we predict should be observable by AdvLIGO across the range of progenitors considered here. The fundamental limitation of these models is in their imposition of axisymmetry. Further progress will require counterpart three-dimensional models.Comment: 10 pages, 5 figure

Evidence for Asphericity in the Type IIn Supernova 1998S

We present optical spectropolarimetry obtained at the Keck-II 10-m telescope on 1998 March 7 UT along with total flux spectra spanning the first 494 days after discovery (1998 March 2 UT) of the peculiar type IIn supernova (SN) 1998S. The SN is found to exhibit a high degree of linear polarization, implying significant asphericity for its continuum-scattering environment. Prior to removal of the interstellar polarization, the polarization spectrum is characterized by a flat continuum (at p ~ 2%) with distinct changes in polarization associated with both the broad (FWZI >= 20,000 km/s) and narrow (unresolved, FWHM < 300 km/s) line emission seen in the total flux spectrum. When analyzed in terms of a polarized continuum with unpolarized broad-line recombination emission, an intrinsic continuum polarization of p ~ 3% results (the highest yet found for a SN), suggesting a global asphericity of >= 45% from the oblate, electron-scattering dominated models of Hoflich (1991). The smooth, blue continuum evident at early times is shown to be inconsistent with a reddened, single-temperature blackbody, instead having a color temperature that increases with decreasing wavelength. Broad emission-line profiles with distinct blue and red peaks are seen in the total flux spectra at later times, perhaps suggesting a disk-like or ring-like morphology for the dense (n_e ~ 10^7 cm^{-3}) circumstellar medium. Implications of the circumstellar scattering environment for the spectropolarimetry are discussed, as are the effects of uncertain removal of interstellar polarization.Comment: 25 pages + 2 tables + 14 figures, Submitted to The Astrophysical Journa

Petrogenesis of Eocene Tamazert continental carbonatites (Central High Atlas, Morocco): implications for a common source for the Tamazert and Canary and Cape Verde Island carbonatites

The Tamazert Eocene alkaline complex of the Central High Atlas Range of Morocco hosts the largest outcropping occurrences of carbonatites in northern Africa. The complex consists of carbonatites and undersaturated ultramafic to syenitic alkaline to peralkaline silicate rocks. Mineralogically and geochemically the Tamazert carbonatites are classified as calciocarbonatites, magnesiocarbonatites and silicocarbonatites.They are enriched in light rare earth elements and large ion lithophile elements (Cs, Rb, Ba, U,Th), but depleted in high field strength elements (particularly, Ti, Nb and Ta). Stable and radiogenic isotope ratios vary in the range of δ13CPDB=-5·8 to 1·8 0/00, δ18OSMOW=6·9-23·5 0/00, initial 87Sr/86Sr=0·7031-0·7076, 143Nd/144Nd=0·5125-0·5129 and 206Pb/204Pb=18·29-19·89. Calciocarbonatites intruding Jurassic limestones have the highest δ13C and δ18O values and the most radiogenic initial 87Sr/86Sr, but least radiogenic 143Nd/144Nd, 206Pb/204Pb and 208Pb/204Pb isotope ratios, and are interpreted to have interacted with the limestones (crustal components). The magnesio- and silicocarbonatites have Sr, Nd and Pb isotope ratios that are nearly identical to those of low-87Sr/86Sr calciocarbonatites. The isotope signature of the high-Sr, low-87Sr/86Sr calciocarbonatites with mantle-type O and C isotopic compositions indicates the presence of HIMU- and EMI-type components in the mantle source of the Tamazert carbonatites, similar to what has been proposed for the Cape Verde and Canary Islands.The close similarity in carbonatite composition between the Cape Verde and Canary Islands and Tamazert suggests a common sublithospheric source for these carbonatites. We therefore propose that theTamazert carbonatites originated through melting of Canary plume material that may have flowed through a sub-lithospheric corridor extending from the Atlantic near the Canary Islands to the Middle Atlas, formed by the delamination of the subcontinental lithosphere in response to Africa-Europe collision at c. 42Ma. Seismic tomography data suggest that the common source may be within the lower mantle at depths >1000 km