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A classic region of band termination at high spin occurs in rare-earth nuclei with around ten valence nucleons above the 146Gd closed core. Results are presented here for such non-collective oblate (γ = 60°) terminating states in odd-Z 155Ho, odd-odd 156Ho, and even-even 156Er, where they are compared with neighbouring nuclei. In addition to these particularly favoured states, the occurrence of collective triaxial strongly deformed (TSD) bands, bypassing the terminating states and extending to over 65ħ, is reviewed. [ABSTRACT FROM AUTHOR]

The Rocky Mountains in the USA and Canada encompass the interior cordillera of western North America, from the southern Yukon to northernNew Mexico. Annual weather patterns are cold in winter and mild in summer. Precipitation has high seasonal and interannual variation and may differ by an order of magnitude between geographically close locales, depending on slope, aspect and local climatic and orographic conditions. The region's hydrology is characterized by the accumulation of winter snow, spring snowmelt and autumnal baseflows. During the 2--3-month 'spring runoff' period, rivers frequently discharge > 70% oftheir annual water budget and have instantaneous discharges 10--100 times mean low flow. Complex weather patterns characterized by high spatial and temporal variability make predictions of future conditionstenuous. However, general patterns are identifiable; northern and western portions of the region are dominated by maritime weather patterns from the North Pacific, central areas and eastern slopes are dominated by continental air masses and southern portions receive seasonally variable atmospheric circulation from the Pacific and the Gulf of Mexico. Significant interannual variations occur in these general patterns, possibly related to ENSO (EI Nino-Southern Oscillation) forcing. Changes in precipitation and temperature regimes or patterns have significant potential effects on the distribution and abundance of plants and animals. For example, elevation of the timber-line is principally a function of temperature. Palaeolimnological investigations have shown significant shifts in phyto- and zoo-plankton populations asalpine lakes shift between being above or below the timber-line. Likewise, streamside vegetation has a significant effect on stream ecosystem structure and function. Changes in stream temperature regimes result in significant changes in community composition as a consequenceof bioenergetic factors. Stenothermic species could be extirpated asappro [ABSTRACT FROM AUTHOR]

Measured, calculated and simulated values were combined to develop an annual nitrogen budget for Loch Vale Watershed (LVWS) in the Colorado Front Range. Nine-year average wet nitrogen deposition values. were 1.6 (s = 0.36) kg NO3-N ha- 1, and 1.0 (s = 0.3) kg NH4-N ha-1. Assuming dry nitrogen deposition to be half that of measured wet deposition, this high elevation watershed receives 3.9 kg N ha-1. Although deposition values fluctuated with precipitation, measured stream nitrogen outputs were less variable. Of the total N input to the watershed (3.9 kg N ha-1 wet plus dry deposition), 49% of the total N input was immobilized. Stream losses were 2.0 kg N ha-1 (1125 kg measured dissolved inorganic N in 1992, 1--2 kg calculated dissolved organic N, plus an average of 203 kg algal N from the entire 660 ha watershed). Tundra and aquatic algae were the largest reservoirs for incoming N, at approximately 18% and 15% of the total 2574 kg N deposition, respectively. Rocky areas and forest stored the remaining 11% and 5%, respectively. Fully 80% of N losses from the watershed came from the 68% of LVWS that is alpine. [ABSTRACT FROM AUTHOR]

Excited states in the neutron-deficient nucleus 72161Hf89 have been populated using the 118Sn(48Ti,5n) 161Hf and 110Pd(56Fe,5n) 161Hf fusion-evaporation reactions at 240 and 270 MeV, respectively. The level scheme for 161Hf has been extended with the observation of new band structures and an Iπ = (13/2+) isomeric state with a half-life of 4.8(2) μs has been identified. The decay path from this isomer to the (7/2-) ground state is established. The yrast band, based on the (13/2+) isomeric state, is extended up to (73/2+) and side band structures are identified up to (69/2-) and (55/2-). Quasiparticle assignments for these rotational structures are made on the basis of their alignment properties and Woods-Saxon cranked shell-model calculations. [ABSTRACT FROM AUTHOR]

We report the results of a study of rotational bands in 219Ra via the 208Pb(14C,3n) reaction to look for evidence that this nucleus is statically octupole deformed. We add 19 γ rays not previously observed to the level scheme and extend the two most strongly populated alternating parity bands to J=51/2 and 45/2. The magnitude of the energy splitting between the spin-parity doublets in the two bands appears to exclude the possibility that 219Ra has a static octupole deformation. [ABSTRACT FROM AUTHOR]

We report the results of a γ-ray spectroscopic study of 211Po via the 208Pb(α,n) reaction at 24-MeV incident energy using a thick target. We observe 26 new γ rays, allowing us to identify 18 states that were not observed in previous γ-ray studies. In total, we observe 45 states below 2.0 MeV. A shell model calculation using the modified Kuo-Herling interaction developed by Warburton and Brown predicts 46 states below 2.0 MeV having spins of 21/2 and below, demonstrating the power of this calculation to provide detailed nuclear structure information on nuclei in the vicinity of 208Pb. [ABSTRACT FROM AUTHOR]

Frameworks for limiting ecosystem exposure to excess nutrients and acidity require accurate and complete deposition budgets of reactive nitrogen (Nr). While much progress has been made in developing total Nr deposition budgets for the U.S., current budgets remain limited by key data and knowledge gaps. Analysis of National Atmospheric Deposition Program Total Deposition (NADP/TDep) data illustrates several aspects of current Nr deposition that motivate additional research. Averaged across the continental U.S., dry deposition contributes slightly more (55%) to total deposition than wet deposition and is the dominant process (>90%) over broad areas of the Southwest and other arid regions of the West. Lack of dry deposition measurements imposes a reliance on models, resulting in a much higher degree of uncertainty relative to wet deposition which is routinely measured. As nitrogen oxide (NO x ) emissions continue to decline, reduced forms of inorganic nitrogen (NH x  = NH 3  + NH 4 ) now contribute >50% of total Nr deposition over large areas of the U.S. Expanded monitoring and additional process-level research are needed to better understand NH + deposition, its contribution to total Nr deposition budgets, and the processes by which reduced N deposits to ecosystems. Urban and suburban areas are hotspots where routine monitoring of oxidized and reduced Nr deposition is needed. Finally, deposition budgets have incomplete information about the speciation of atmospheric nitrogen; monitoring networks do not capture important forms of Nr such as organic nitrogen. Building on these themes, we detail the state of the science of Nr deposition budgets in the U.S. and highlight research priorities to improve deposition budgets in terms of monitoring and flux measurements, leaf- to regional-scale modeling, source apportionment, and characterization of deposition trends and patterns.x deposition, its contribution to total Nr deposition budgets, and the processes by which reduced N deposits to ecosystems. Urban and suburban areas are hotspots where routine monitoring of oxidized and reduced Nr deposition is needed. Finally, deposition budgets have incomplete information about the speciation of atmospheric nitrogen; monitoring networks do not capture important forms of Nr such as organic nitrogen. Building on these themes, we detail the state of the science of Nr deposition budgets in the U.S. and highlight research priorities to improve deposition budgets in terms of monitoring and flux measurements, leaf- to regional-scale modeling, source apportionment, and characterization of deposition trends and patterns., (Published by Elsevier B.V.)