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Increasing global CO2 and local land use changes coupled with increased nutrient pollution are threatening estuaries worldwide. Local changes of estuarine chemistry have been documented, but regional associations and trends comparing multiple estuaries latitudinally have not been evaluated. Rapid climate change has impacted the annual and decadal chemical trends in estuaries, with local ecosystem processes enhancing or mitigating the responses. Here, we compare pH, dissolved oxygen, temperature, and salinity data from 10 Florida shellfish estuaries and hundreds of shellfish bed stations. Over 80,000 measurements, spanning from 1980 to 2008, taken on Atlantic Ocean and West Florida coast showed significant regional trends of consistent pH decreases in 8 out of the 10 estuaries, with an average rate of decrease on the Gulf of Mexico side estuaries of Florida of 7.3 × 10−4 pH units year−1, and average decrease on the Atlantic Coast estuaries of 5.0 × 10−4 pH units year−1. The rates are approximately 2-3.4 times slower than observed in pH decreases associated with ocean acidification in the Atlantic and Pacific. Other significant trends observed include decreasing dissolved oxygen in 9 out of the 10 estuaries, increasing salinity in 6 out of the 10, and temperature increases in 3 out of the 10 estuaries. The data provide a synoptic regional view of Florida estuary trends which reflect the complexity of changing climate and coastal ocean acidification superimposed on local conditions. These data provide context for understanding, and interpreting the past and predicting future of regional water quality health of shellfish and other organisms of commercial and ecological significance along Florida’s coasts. [ABSTRACT FROM AUTHOR]

The McMurdo Dry Valleys of Antarctica form the coldest and driest ecosystem on Earth. Within this region there are a number of perennially ice-covered (3-6 m thick) lakes that support active microbial assemblages and have a paucity of metazoans. These lakes receive limited allochthonous input of carbon and nutrients, and primary productivity is limited to only 6 months per year owing to an absence of sunlight during the austral winters. In an effort to establish the role that bacteria and their associated viruses play in carbon and nutrient cycling in these lakes, indigenous bacteria, free bacteriophage, and lysogen abundances were determined. Total bacterial abundances (TDC) ranged from 3.80 x 104 to 2.58 x 107 cells mL-1 and virus-like particle (VLP) abundances ranged from 2.26 x 105 to 5.56 x 107 VLP mL-1. VLP abundances were significantly correlated (P < 0.05) with TDC, bacterial productivity (TdR), chlorophyll a (Chl a), and soluble reactive phosphorus (SRP). Lysogenic bacteria, determined by induction with mitomycin C, made up between 2.0% and 62.5% of the total population of bacteria when using significant decreases and increases in TDC and VLP abundances, respectively, and 89.5% when using increases in VLP abundances as the sole criterion for a successful induction event. The contribution of viruses released from induced lysogens contributed <0.015% to the total viral production rate. Carbohydrate and protein based organic aggregates were abundant within the water column of the lakes and were heavily colonized by bacteria and VLPs. Alkaline phosphatase activity was detected within the matrix of the aggregates, implying phosphorus deficiency and consortial nutrient exchanges among microorganisms. [ABSTRACT FROM AUTHOR]

Theπh9/2[541 1/2−] band in 167Tm has been studied through the 124Sn(48Ca, p4n)167Tm reaction at Ebeam = 210 MeV. The favoured signature of the πh9/2[541 1/2−] band is observed to spin 61/2h̅. A remarkable small gain in aligned angular momentum at the AB-band crossing has been found. The crossing frequency and the gain in aligned angular momentum for 167Tm are compared with data for the N = 98 isotones of Lu, Ta and Re, and contrasted with Cranked Shell Model predictions, based on frequency diabatic configurations. Large deviations are found for the gain in aligned angular momentum. [ABSTRACT FROM AUTHOR]

High spin states ofPt have been populated inSm(Cl, pxn) reactions at beam energies of 175-185 MeV. In-beam γ-ray spectroscopic techniques using the ESSA30 spectrometer array were adopted. Levels up to spin 26 inPt and tentatively up to spin 45/2 inPt have been identified. The data are interpreted within the framework of Cranked Shell Model calculations using the deformed Woods-Saxon potential and including monopole pairing. [ABSTRACT FROM AUTHOR]

TheNi(Si, αpn)Y reaction at a beam energy of 134 MeV was used to populate the odd-odd nucleusY and coincident γ rays depopulating high spin states in the evaporation residues were detected with the EUROGAM Phase 2 array. A superdeformed structure has been observed with an intensity of 1.5±0.5%. The cascade of 9 coincident γ rays has consecutive energy spacing of ∼160 keV. This corresponds to a dynamic moment of inertia which is almost constant at approx mately 25 h MeV. The band is interpreted as a signature=0, negative parity SD band with a π5 V5 intrinsic intruder configuration. [ABSTRACT FROM AUTHOR]

The yrast bands ofGd andDy have been observed to high spins (I∼25-40). The systematic properties of the N=91 isotones with particular reference to the second i neutron and first h proton alignments are discussed. [ABSTRACT FROM AUTHOR]

Two-dimensional γ-ray energy correlations have been measured at high spins in0s with the TESSA2 spectrometer. The E − Ecorrelation matrix displays ridges characteristic of rotational bands with different energy separations of 96± and 72± keV for the energy regions of 660 to 840 keV and 975 to 1170 keV, respectively. The separation of these ridges remains constant in both energy regions. The dynamical moments of inertia are θ =83±3 and 111±5 ħ/MeV, respectively. The latter value suggests superdeformation in0s with an axis ratio c/a=1.76 (β ≅0.64) at high spins. [ABSTRACT FROM AUTHOR]