Vegetation and climate c. 12 300-9000 cal. yr BP at Andoya, NW Norway

Owing to proximity of the North Atlantic Stream and the shelf, the And circle divide ya biota are assumed to have responded rapidly to climatic changes taking place after the Weichselian glaciation. Palynological, macrofossil, loss-on-ignition, tephra and C-14 data from three sites at the northern part of the island of And circle divide ya were studied. The period 12 300-11 950 cal. yr BP was characterized by polar desert vegetation, and 11 950-11 050 cal. yr BP by a moisture-demanding predominantly low-arctic Oxyria vegetation. During the period 11 050-10 650 cal. yr BP, there was a climatic amelioration towards a sub-arctic climate and heaths dominated by Empetrum. After 10 650 cal. yr BP the Oxyria vegetation disappeared. As early as about 10 800 cal. yr BP the bryozoan Cristatella mucedo indicated a climate sufficient for Betula woodland. However, tree birch did not establish until 10 420-10 250 cal. yr BP, indicating a time-lag for the formation of Betula ecotypes adapted to the oceanic climate of And circle divide ya. From about 10 150 to 9400 cal. yr BP the summers were dry and warm. There was a change towards moister, though comparatively warm, climatic conditions about 9400 cal. yr BP. The present data are compared with evidence from marine sediments and the deglaciation history in the region. It is suggested that during most of the period 11 500-10 250 cal. yr BP a similar situation as in present southern Greenland existed, with birch woodland in the inner fjords near the ice sheet and low-arctic heath vegetation along the outer coast.

The mid-infrared dielectric function of NBCO in the a-b plane from 85 K to 300 K

Results are reported on the a-b plane dielectric function (epsilon) of thin-film c-axis NdBa2Cu3O7-delta with close to optimal oxygen doping (T-c similar to 90 K) in the mid-infrared (wavelength 3.392 mum) over the temperature range 85 K to 300 K. An attenuated total reflectance technique based on the excitation of surface plasmon polaritons is used. The results show that \epsilon (r)\ decreases quasi-linearly with increasing temperature, while Ei is invariant with temperature to within experimental uncertainties. Representative values are epsilon = [epsilon (r) + i epsilon (i)] = (-12.9 +/- 0.6) + i(23.0 +/- 1.5) at T similar to 295 K and epsilon = (-15.7 +/- 0.7) + i(23.5 +/- 1.1) at T similar to 90 K. The raw data an interpreted in terms of the generalized Drude model which gives effective scattering rates (1/tau*) that increase with temperature from about 3800 cm(-1) at 90 K to about 4300 cm(-1) at 295 K. There are indications of a superlinear T-dependence in the scattering, 1/tau*: a fit to a function of the form 1/tau* = A + BTalpha gives alpha = 2.8 +/- 0.7. The effective plasma frequency, omega (p)*, with an average value of approximately 21 000 cm(-1) was independent of temperature.

Characterization of optical properties of PtSi at 3.392 mu m from 300 K to 85 K and relation of morphological effects

PtSi/Si Schottky junctions, fabricated using a conventional technique of Pt deposition with a subsequent thermal anneal, are examined using X-ray diffraction, atomic force microscopy and a novel prism/gap/sample optical coupling system. With the aid of X-ray diffraction and atomic farce microscopy it is shown that a post-anneal etch in aqua regia is essential for the removal of an unreacted, rough surface layer of Pt, to leave a much smoother PtSi film. The prism/gap/sample or Otto coupling rig is mounted in a small UHV chamber and has facilities for remote variation of the gap (by virtue of a piezoactuator system) and variation of the temperature in the range of similar to 300 K - 85 K. The system is used to excite surface plasmon polaritons on the outer surface of the PtSi and thus produce sensitive optical characterisation as a function of temperature. This is performed in order to yield an understanding of the temperature dependence of phonon and interface scattering of carriers in the PtSi.

DC resistance and dielectric function at 3392 nm of YBCO films from 300 K to 80 K

The dielectric function of a YBCO film was determined at 3392nm at temperatures down to 80K. Results obtained were epsilon(i) = -24.09 - 0.0013T and epsilon(i) = 7.66 + 0.067T. The results for epsilon(i) are compared with the de resistance of the film. Intrinsic intragrain scattering, elastic and inelastic grain boundary scattering and optical interband absorption are estimated as 82%, 5%, 13% and 10% respecively at 0K.

Urban/rural variation in the influence of widowhood on mortality risk: a cohort study of almost 300,000 couples

Death of a spouse is associated with increased mortality risk for the surviving partner (the widowhood effect). We investigated whether the effect magnitude varied between urban, rural and intermediate areas, assembling death records (2001-2009) for a prospective cohort of 296,125 married couples in Northern Ireland. The effect was greatest during the first six months of widowhood in all areas and for both sexes. Subsequently, the effect was attenuated among men in rural and intermediate areas but persisted in urban areas (HRs and 95% CIs: rural 1.09 [0.99, 1.21]; urban 1.35 [1.26, 1.44]). Among women the effect was attenuated in all areas (rural 1.06 [0.96, 1.17]; urban 1.09 [1.01, 1.17]). The impacts of spousal bereavement varied between urban and more rural areas, possibly due to variation in social support provided by the wider community. We identify men in urban areas as being in greatest need of such support and a possible target for health interventions.

Calibration of BAS-TR image plate response to high energy (3-300 MeV) carbon ions

The paper presents the calibration of Fuji BAS-TR image plate (IP) response to high energy carbon ions of different charge states by employing an intense laser-driven ion source, which allowed access to carbon energies up to 270 MeV. The calibration method consists of employing a Thomson parabola spectrometer to separate and spectrally resolve different ion species, and a slotted CR-39 solid state detector overlayed onto an image plate for an absolute calibration of the IP signal. An empirical response function was obtained which can be reasonably extrapolated to higher ion energies. The experimental data also show that the IP response is independent of ion charge states.

Comments on “High-temperature creep resistance and effects on the austenite reversion and precipitation of 18 Ni (300) maraging steel” by dos Reis et al. [Materials Characterization 107 (2015) 350- 357]

This letter attempts to comment on an article by dos Reis et al., in the aspects of creep considerationand chemical analysis in maraging steels.