Investigation of N. pachyderma from the North Atlantic

The shells of the planktonic foraminifer Neogloboquadrina pachyderma have become a classical tool for reconstructing glacial-interglacial climate conditions in the North Atlantic Ocean. Palaeoceanographers utilize its left- and right-coiling variants, which exhibit a distinctive reciprocal temperature and water mass related shift in faunal abundance both at present and in late Quaternary sediments. Recently discovered cryptic genetic diversity in planktonic foraminifers now poses significant questions for these studies. Here we report genetic evidence demonstrating that the apparent 'single species' shell-based records of right-coiling N. pachyderma used in palaeoceanographic reconstructions contain an alternation in species as environmental factors change. This is reflected in a species-dependent incremental shift in right-coiling N. pachyderma shell calcite d18O between the Last Glacial Maximum and full Holocene conditions. Guided by the percentage dextral coiling ratio, our findings enhance the use of d18O records of right-coiling N. pachyderma for future study. They also highlight the need to genetically investigate other important morphospecies to refine their accuracy and reliability as palaeoceanographic proxies.

Sea-floor images from ROV transects during POLARSTERN cruise ANT-XVII/3 (EASIZ III) to the Weddell Sea, Antarctica

Transects of a Remotely Operated Vehicle (ROV) providing sea-bed videos and photographs were carried out during POLARSTERN expedition ANT-XVII/3 focussing on the ecology of benthic assemblages on the Antarctic shelf in the South-Eastern Weddell Sea. The ROV-system sprint 103 was equiped with two video- and one still camera, lights, flash-lights, compass, and parallel lasers providing a scale in the images, a tether-management system (TMS), a winch, and the board units. All cameras used the same main lense and could be tilted. Videos were recorded in Betacam-format and (film-)slides were made by decision of the scientific pilot. The latter were mainly made under the aspect to improve the identification of organisms depicted in the videos because the still photographs have a much higher optical resolution than the videos. In the photographs species larger than 3 mm, in the videos larger than 1 cm are recognisable and countable. Under optimum conditions the transects were strait; the speed and direction of the ROV were determined by the drift of the ship in the coastal current, since both, the ship and the ROV were used as a drifting system; the option to operate the vehicle actively was only used to avoide obstacles and to reach at best a distance of only approximately 30 cm to the sea-floor. As a consequence the width of the photographs in the foreground is approximately 50 cm. Deviations from this strategy resulted mainly from difficult ice- and weather conditions but also from high current velocity and local up-welling close to the sea-bed. The sea-bed images provide insights into the general composition of key species, higher systematic groups and ecological guilds. Within interdisciplinary approaches distributions of assemblages can be attributed to environmental conditions such as bathymetry, sediment characteristics, water masses and current regimes. The images also contain valuable information on how benthic species are associated to each other. Along the transects, small- to intermediate-scaled disturbances, e.g. by grounding icebergs were analysed and further impact to the entire benthic system by local succession of recolonisation was studied. This information can be used for models predicting the impact of climate change to benthic life in the Southern Ocean. All these approaches contribute to a better understanding of the fiunctioning of the benthic system and related components of the entire Antarctic marine ecosystem. Despite their scientific value the imaging methods meet concerns about the protection of sensitive Antarctic benthic systems since they are non-invasive and they also provide valuable material for education and outreach purposes.

Supercapattery based on binder-free Co3 (PO4)2·8H2O multilayer nano/microflakes on nickel foam

A binder-free cobalt phosphate hydrate (Co3(PO4)2·8H2O) multilayer nano/microflake structure is synthesized on nickel foam (NF) via a facile hydrothermal process. Four different concentrations (2.5, 5, 10, and 20 mM) of Co2+ and PO4–3 were used to obtain different mass loading of cobalt phosphate on the nickel foam. The Co3(PO4)2·8H2O modified NF electrode (2.5 mM) shows a maximum specific capacity of 868.3 C g–1 (capacitance of 1578.7 F g–1) at a current density of 5 mA cm–2 and remains as high as 566.3 C g–1 (1029.5 F g–1) at 50 mA cm–2 in 1 M NaOH. A supercapattery assembled using Co3(PO4)2·8H2O/NF as the positive electrode and activated carbon/NF as the negative electrode delivers a gravimetric capacitance of 111.2 F g–1 (volumetric capacitance of 4.44 F cm–3). Furthermore, the device offers a high specific energy of 29.29 Wh kg–1 (energy density of 1.17 mWh cm–3) and a specific power of 4687 W kg–1 (power density of 187.5 mW cm–3).

Incisión fluvial del río Darro durante el periodo 1890-2010 en el sector urbano de Granada (Alambra-Valparaíso, España) determinada a partir de fotografías históricas

En este trabajo se calcula la tasa media de incisión fluvial del río Darro (Granada, España) durante el periodo 1890-2010 en su tramo urbano (sector Alhambra-Valparaíso). Para ello se han utilizado fotografías históricas en las que aparece dicho río, a partir de las cuales se ha podido determinar la posición del cauce en el momento en el que se realizaron las fotografías. La comparación con los escenarios actuales de tales imágenes ha permitido determinar la diferencia de altura del cauce a través de medidas de cotas absolutas realizadas mediante teodolito. Esta metodología ha permitido estimar de modo cuantitativo un índice de encajamiento vertical medio del río de 1,05 cm/año para el periodo histórico considerado.

Gambling and violence in a nationally representative sample of UK men

The relationship between violence and problem gambling in general population samples is under-researched and requires further attention to inform treatment and prevention efforts. We investigated the relationship between gambling problems and violence among men and sought to determine if the link can be accounted for by mental disorders, alcohol and drug dependence and impulsivity.

Considerações sobre os relatórios : avaliação de receitas e despesas do 4º bimestre : cumprimento de metas do 2º quadrimestre de 2013 : Decreto nº 8.111/2013 (30 de setembro)

Consultoria de Orçamento e Fiscalização Financeira. Núcleo de Assuntos Econômico-Fiscais

A spectroscopic study of the chemistry and reactivity of SO2 on Pt{111}: Reactions with O-2, CO and C3H6

The chemisorption and reactivity of SO2 on Pt{111} have been studied by HREELS, XPS, NEXAFS and temperature-programmed desorption. At 160 K SO2 adsorbs intact at high coverages, with eta(2) S-O coordination to the surface. On annealing to 270 K, NEXAFS indicates the SO2 molecular plane essentially perpendicular to the surface. Preadsorbed O-a reacts with SO2 to yield adsorbed SO4, identified as the key surface species responsible for SO2-promoted catalytic alkane oxidation. Coadsorbed CO or propene efficiently reduce SO2 overlayers to deposit S-a, and the implications of this for catalytic systems are discussed.

Electric field gradients in (111)In-doped (Hf/Zr)(3)Al(2) and (Hf/Zr)(4)Al(3) mixed compounds: ab initio calculations, perturbed angular correlation measurements and site preference

The quadrupolar hyperfine interactions of in-diffused (111)In -> (111)Cd probes in polycrystalline isostructural Zr(4)Al(3) and Hf(4)Al(3) samples containing small admixtures of the phases (Zr/Hf)(3)Al(2) were investigated. A strong preference of (111)In solutes for the contaminant (Zr/Hf)(3)Al(2) minority phases was observed. Detailed calculations of the electric field gradient (EFG) at the Cd nucleus using the full-potential augmented plane wave + local orbital formalism allowed us to assign the observed EFG fractions to the various lattice sites in the (Zr/Hf)(3)Al(2) compounds and to understand the preferential site occupation of the minority phases by the (111)In atoms. The effects of the size of the supercell and relaxation around the oversized In and Cd probe atoms were investigated in detail.

Hyperfine interaction studies with (181)Ta and (111)Cd probes in the compound Ti(2)Ag

By using the time-differential perturbed angular correlation technique, the electric field gradients (EFG) at (181)Hf/(181)Ta and (111)In/(111)Cd probe sites in the MoSi(2)-type compound Ti(2)Ag have been measured as a function of temperature in the range from 24 to 1073 K. Ab initio EFG calculations have been performed within the framework of density functional theory using the full-potential augmented plane wave + local orbitals method as implemented in the WIEN2k package. These calculations allowed assignments of the probe lattice sites. For Ta, a single well-defined EFG with very weak temperature dependence was established and attributed to the [4(e)4mm] Ti site. For (111)Cd probes, two of the three measured EFGs are well defined and correlated with substitutional lattice sites, i.e. both the [4(e)4mm] Ti site and the [2(a)4/mmm] Ag site.

Chemisorbed and physisorbed Structures for 1,10-Phenanthroline and Dipyrido[3,2-a:2',3'-c]phenazine on Au(111)

Scanning tunneling microscopy (STM) images of 1,10-phenanthroline (PHEN) and dipyrido[3,2-a:2‘,3‘-c]phenazine (DPPZ) on Au(111) are recorded using both in situ and ex situ techniques. The images of PHEN depict regimes of physisorption and chemisorption, whereas DPPZ is only physisorbed. All physisorbed structures are not pitted and fluctuate dynamically, involving aligned (4 × 4) surface domains with short-range (ca. 20 molecules) order for PHEN but unaligned chains with medium-range (ca. 100 molecules) order for DPPZ. In contrast, the chemisorbed PHEN monolayers remain stable for days, are associated with surface pitting, and form a (4 × √13)R46° lattice with long-range order. The density of pitted atoms on large gold terraces is shown to match the density of chemisorbed molecules, suggesting that gold adatoms link PHEN to the surface. For PHEN, chemisorbed and physisorbed adsorbate structures are optimized using plane-wave density-functional theory (DFT) calculations for the surface structure. Realistic binding energies are then obtained adding dispersive corrections determined using complete-active-space self-consistent field calculations using second-order perturbation theory (CASPT2) applied to cluster-interaction models. A fine balance between the large adsorbate−adsorbate dispersive forces, adsorbate−surface dispersive forces, gold ligation energy, and surface mining energy is shown to dictate the observed phenomena, leading to high surface mobility and substrate/surface lattice incommensurability. Increasing the magnitude of the dispersive forces through use of DPPZ, rather than PHEN, to disturb this balance produced physisorbed monolayers without pits and/or surface registration but with much longer-range order. Analogies are drawn with similar but poorly understood processes involved in the binding of thiols to Au(111).

[(99m)Tc]Demotate 2 in the detection of sst(2)-positive tumours: a preclinical comparison with [(111)In]DOTA-tate

PURPOSE: The aim of this study was to evaluate [(99m)Tc]Demotate 2 ([(99m)Tc-N(4) (0-1),Asp(0),Tyr(3)]octreotate) as a candidate for in vivo imaging of sst(2)-positive tumours and to compare it with [(111)In]DOTA-tate ([(111)In-DOTA(0),Tyr(3)]octreotate). METHODS: Labelling of Demotate 2 with (99m)Tc was performed at room temperature using SnCl(2) as reductant in the presence of citrate at alkaline pH. Radiochemical analysis involved ITLC and HPLC methods. Peptide conjugate affinities for sst(2) were determined by receptor autoradiography on rat brain cortex sections using [DOTA(0),(125)I-Tyr(3)]octreotate as the radioligand. The affinity profile of Demotate 2 for human sst(1)-sst(5) was studied by receptor autoradiography in cell preparations using the universal somatostatin radioligand [(125)I][Leu(8),(D: )Trp(22),Tyr(25)]somatostatin-28. The internalisation rates of [(99m)Tc]Demotate 2 and [(111)In]DOTA-tate were compared in sst(2)-positive and -negative control cell lines. Biodistribution of radiopeptides was studied in male Lewis rats bearing CA20948 tumours. RESULTS: Peptide conjugates showed selectivity and a high affinity binding for sst(2) (Demotate 2 IC(50)=3.2 nM and DOTA-tate IC(50)=5.4 nM). [(99m)Tc]Demotate 2, like [(111)In]DOTA-tate, internalised rapidly in all sst(2)-positive cells tested, but not in sst(2)-negative control cells. After injection in CA20948 tumour-bearing rats both radiopeptides showed high and specific uptake in the sst(2)-positive organs and in the implanted tumour and rapid excretion from non-target tissues via the kidneys. CONCLUSION: [(99m)Tc]Demotate 2, similarly to the known sst(2)-targeting agent [(111)In]DOTA-tate, showed promising biological qualities for application in the scintigraphy of sst(2)-positive tumours.