First description of seagrass distribution and abundance in Sao Tome and Principe

Seagrass meadows in Sao Tome and Principe, eastern Atlantic Ocean, are described here for the first time. Specifically, we quantified the biomass and density of seagrasses, characterized the plant morphology and measure their nutrient content as a proxy of the nutrient environmental conditions where the meadows develop. The seagrass Halodule wrightii was found in two locations of the northeastern coast of the island of Sao Tome: 1) developing throughout an estimated area of 1500 ha surrounding Cabras islet, at a depth range of 4-10 m, on sandy bottom; and 2) at Santana bay with an area of 1500 m(2) at 5-10 m depth, on sandy bottom. A highly morphologically different population of Halodule wrightii was found on the northeastern coast of the island of Principe, off Abade beach, covering an area of 135 m2 at 4 m depth. Further research is needed to assess if this is a different species. Shoot biomass and density was 10 and 4-fold higher in Sao Tome than in Principe, respectively. CN ratios of above and belowground tissues of plants collected in Sao Tome were also significantly higher than in Principe. The carbon content of Halodule leaves from Sao Tome and Principe (41%) was much higher than that reported for other Halodule species, suggesting that meadows may have an important ecological role for carbon fixation. The presence of H. wrightii in Sao Tome and Principe raises ecological and evolutionary questions that warrant further research.PADI Foundation [21670

A cationic and ferromagnetic hexametallic Mn(III) single-molecule magnet based on the salicylamidoxime ligand

The salicylamidoxime-based complex [Mn-6(mu(3)-O)(2)(N-H2-sao)(6)(py)(6)(EtOH)(2)](ClO4)(2)center dot 4EtOH (1.4EtOH) constitutes the first example of a cationic and ferromagnetic member of the oxime-based family of [Mn-6(III)] single-molecule magnets.</p

On the connections between Skyrme and Yang Mills theories

Skyrme theories on S^3 and S^2, are analyzed using the generalized zero curvature in any dimensions. In the first case, new symmetries and integrable sectors, including the B =1 skyrmions, are unraveled. In S^2 the relation to QCD suggested by Faddeev is discussedComment: Talk at the Workshop on integrable theories, solitons and duality. IFT Sao Paulo July 200

Confinement in (2+1)-Dimensional Gauge Theories at Weak Coupling

In axial gauge, the (2+1)-dimensional SU($N$) Yang-Mills theory is equivalent to a set of (1+1)-dimensional integrable models with a non-local coupling between charge densities. This fact makes it possible to determine the static potential between charges at weak coupling in an anisotropic version of the theory, and understand features of the spectrum.Comment: Four pages, Based on a talk given at ``Quark Confinement and the Hadron Spectrum 7", Ponta Delgada, Sao Miguel, Azores, Portugal, Sept. 2-7, 200

Disk Imaging Survey of Chemistry with SMA: II. Southern Sky Protoplanetary Disk Data and Full Sample Statistics

This is the second in a series of papers based on data from DISCS, a Submillimeter Array observing program aimed at spatially and spectrally resolving the chemical composition of 12 protoplanetary disks. We present data on six Southern sky sources - IM Lup, SAO 206462 (HD 135344b), HD 142527, AS 209, AS 205 and V4046 Sgr - which complement the six sources in the Taurus star forming region reported previously. CO 2-1 and HCO+ 3-2 emission are detected and resolved in all disks and show velocity patterns consistent with Keplerian rotation. Where detected, the emission from DCO+ 3-2, N2H+ 3-2, H2CO 3-2 and 4-3,HCN 3-2 and CN 2-1 are also generally spatially resolved. The detection rates are highest toward the M and K stars, while the F star SAO 206462 has only weak CN and HCN emission, and H2CO alone is detected toward HD 142527. These findings together with the statistics from the previous Taurus disks, support the hypothesis that high detection rates of many small molecules depend on the presence of a cold and protected disk midplane, which is less common around F and A stars compared to M and K stars. Disk-averaged variations in the proposed radiation tracer CN/HCN are found to be small, despite two orders of magnitude range of spectral types and accretion rates. In contrast, the resolved images suggest that the CN/HCN emission ratio varies with disk radius in at least two of the systems. There are no clear observational differences in the disk chemistry between the classical/full T Tauri disks and transitional disks. Furthermore, the observed line emission does not depend on measured accretion luminosities or the number of infrared lines detected, which suggests that the chemistry outside of 100 AU is not coupled to the physical processes that drive the chemistry in the innermost few AU.Comment: accepted for publication in ApJ, 41 pages including 7 figure

Rapidity Dependence of HBT radii based on a hydrodynamical model

We calculate two-pion correlation functions at finite rapidities based on a hydrodynamical model which does not assume explicit boost invariance along the collision axis. Extracting the HBT radii through $\chi^2$ fits in both Cartesian and Yano-Koonin-Podgoretski\u{\i} parametrizations, we compare them with the experimental results obtained by the PHOBOS. Based on the results, we discuss longitudinal expansion dynamics.Comment: 8 pages, 10 figures, talk given at II Workshop on Particle Correlation and Femtoscopy (WPCF 2006), Sep 9-11, Sao Paulo, Brazil. Revised version to be published in Braz.J.Phy

Charmonium and Bottomonium from Classical SU(3) Gauge Configurations

The charmonium and bottomonium spectra computed from a potential defined from a single gauge configuration, obtained from solving the classical field equations, is discussed. The theoretical spectra shows good agreement with the measured states. A discussion of possible interpretations, within the same non-relativistic potential model, for the new charmonia states X(3872), $\chi_{c1} (2P)$ and Y(4260) is performed. In particular, we give predictions for electromagnetic E1 transitions for various scenarios.Comment: Talk given at "Quark Confinement and the Hadron Spectrum VII", Ponta Delgada, Sao Miguel, Azores, Portugal, Sept. 2-7, 200