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The structures of the Group 1 metal aminoalkoxides Li[OCH(CH2CNMe2)2] (1) and K[OCH(CH2CNMe2)2]∙HOCH(CH2CNMe2)2 (2) have been determined. 1 is a hexa­meric drum in which two Li3O3 rings are joined co-facially, whereas 2 is tetrameric and adopts a K4O4 ladder structure, novel for homoleptic potassium alkoxides.

This work demonstrates p-type SnO thin film transistors, where the SnO active layers were deposited with atomic layer deposition (ALD) using the Sn(II) alkoxide precursor, Sn(II) bis(tert-butoxide). The deposition optimisation explores the use of multiple Sn pulses per ALD cycle and the use of an exposure mode (where the pump extraction is paused before the Sn precursor purge) to increase the residence time and allow for more effective saturation of the surface. The fabricated devices required post deposition annealing of the active layer, with device performance further improved by back-channel passivation using ALD Al2O3. The performance of devices deposited using the varying precursor delivery modes has also been compared, with the devices utilizing deposition with multiple Sn pulses and a post deposition anneal at 250 °C achieving an on/off ratio of ∼4 × 104 and field effect mobility (μFE) of 0.6 cm2 (V s)−1. The growth processes present during deposition with the different precursor delivery modes was investigated using fractal geometry and topographical scaling methods, with the poor device performance for the single Sn pulse deposition attributed to 2D lateral island growth. [ABSTRACT FROM AUTHOR]

Obtaining temperature data from the mid-Piacenzian warm period (ca. 3 Ma, Pliocene epoch) is a key factor in outlining the impact of projected anthropogenic climate change. The mid-Piacenzian warm period was a high-CO2 world with a paleogeography similar to modern times. The time interval has been used to validate and improve climate model retrodictions, which in turn enables assessing the predictive strength of these models. Validating climate models requires a large array of robust proxy data. Here, we increase the potential of this proxy database by showing that the extinct tellinid bivalve Angulus benedeni benedeni can be used for stable isotope-based temperature reconstructions. This species is found in the Pliocene sediments of the southern North Sea basin. Oxygen isotope and carbonate clumped isotope measurements on the shell of A. benedeni benedeni resulted in a mean annual temperature reconstruction of 13.5±3.8 °C. This is 2.5 °C warmer than today, 3.5 °C warmer than the pre-industrial North Sea, and in line with global Pliocene temperature estimates of +2–4 °C compared to the pre-industrial climate. Limited amounts of clumped isotope data hindered determining summer and winter temperatures, but the oxygen isotope record shows that the growth band spacing of A. benedeni benedeni allows for sampling at a resolution of 2–3 months. The species could live for up to a decade, and therefore has the potential to be used for multiannual seasonality reconstructions. The pristine nature of the aragonitic shell material was verified through electron backscatter diffraction analysis (EBSD), and backed by light microscopy, X-ray diffraction, and X-ray fluorescence. The various microstructures as obtained from the EBSD maps have been described, and they provide a template of pristine A. benedeni benedeni material to which potentially altered shells may be compared. The bivalve A. benedeni benedeni is suitable for high resolution isotope-based paleoclimatic reconstruction and it can be used to unravel the marine conditions in the Pliocene southern North Sea basin at a seasonal scale, yielding enhanced insights into imminent western European climate conditions. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2007.03.041 Byline: Andrew L. Johnson (a), Leon F. McGinnis (b) Keywords: Data envelopment analysis; Productivity; Inefficient frontier; Outlier detection Abstract: In the use of peer group data to assess individual, typical or best practice performance, the effective detection of outliers is critical for achieving useful results, particularly for two-stage analyses. In the DEA-related literature, prior work on this issue has focused on the efficient frontier as a basis for detecting outliers. An iterative approach for dealing with the potential for one outlier to mask the presence of another has been proposed but not demonstrated. This paper proposes using both the efficient frontier and the inefficient frontier to identify outliers and thereby improve the accuracy of second stage results in two-stage nonparametric analysis. The iterative outlier detection approach is implemented in a leave-one-out method using both the efficient frontier and the inefficient frontier and demonstrated in a two-stage semi-parametric bootstrapping analysis of a classic data set. The results show that the conclusions drawn can be different when outlier identification includes consideration of the inefficient frontier. Author Affiliation: (a) Department of Industrial and Systems Engineering, Texas A&M University, College Station, TX 77840, USA (b) Department of Industrial and Systems Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA Article History: Received 9 November 2005; Accepted 26 March 2007

Warehouse design and operations have undergone major changes over the past decades. In particular, with the onset of e-commerce, the complexity of warehouse operations has increased multi-fold with the storage of large SKU assortment in small quantities, volatile demand patterns and primarily single-line customer orders. They have grown in size due to consolidation, new and fast identification and communication technologies have found their way into the warehouse and process automation technologies have progressed improving speed and operational efficiencies. In line with these developments, this special issue pays attention to new technologies and methods and how they impact warehouse design and management. [ABSTRACT FROM AUTHOR]

Cemetery T at Naqada has been postulated as being the interment site of a predunastic royal or ruling elite due to its small, localized area and the richness of its burial goods. In order to examine possible biological differentiation between the individuals buried in Cemetery T and those buried in other, possibly lower status cemeteres at Naqada, nonmetric dental morphological data were analyzed using the Mean Measure of Divergence statistic. Results indicate that Cemetery T shows some biological distinction from both Cemetery B and the Great Cemetery. The size of the difference supports the archaeological interpretation that Cemetery T represents a ruling or elite segment (or lineage) of the local population at Naqada, rather than a ruling or elite immigrant population. Given the problem of small samples, however, this interpretation is tentative.

Oxygen isotope (δ18O) sclerochronology of benthic marine molluscs provides a means of reconstructing the seasonal range in seafloor temperature, subject to use of an appropriate equation relating shell δ18O to temperature and water δ18O, reasonably accurate estimation of water δ18O, and due consideration of growth-rate effects. Taking these factors into account, δ18O data from late Pliocene bivalves of the southern North Sea Basin (Belgium and the Netherlands) indicate a seasonal seafloor range at times larger than now in the area. Microgrowth-increment data from Aequipecten opercularis, together with the species-composition of the bivalve assemblage and aspects of preservation, suggest a setting below the summer thermocline for all but the latest material investigated. This implies a higher summer temperature at the surface than on the seafloor and consequently a greater seasonal range. A conservative (3 °C) estimate of the difference between maximum seafloor and surface temperature under circumstances of summer stratification points to seasonal surface ranges in excess of the present value (12.4 °C nearby). Using model-constrained estimates of water δ18O, summer surface temperature was initially in the cool temperate range (< 20 °C) and then (during the Mid-Piacenzian Warm Period; MPWP) increased into the warm temperate range (> 20 °C) before reverting to cool temperate values (in conjunction with shallowing and a loss of summer stratification). This pattern is in agreement with biotic-assemblage evidence. Winter temperature was firmly in the cool temperate range (< 10 °C) throughout, contrary to previous interpretations. Averaging of summer and winter surface temperatures for the MPWP provides a figure for mean annual sea-surface temperature that is 2-3 °C higher than the present value (10.9 °C nearby) and in close agreement with a figure obtained by averaging alkenone- and TEX86-temperatures for the MPWP from the Netherlands. These proxies, however, respectively underestimate summer temperature and overestimate winter temperature, giving an incomplete picture of seasonality. A higher mean annual temperature than now is consistent with the notion of global warmth in the MPWP, but a low winter temperature in the southern North Sea Basin suggests regional reduction in oceanic heat supply, contrasting with other interpretations of North Atlantic oceanography during the interval. Carbonate clumped isotope (Δ47) and biomineral unit thermometry offer means of checking the δ18O-based temperatures. [ABSTRACT FROM AUTHOR]

Yardstick competition is a regulation regime that forces local monopolies to compete against a variable cost or total cost benchmark. The variable cost benchmark ignores the fixed capital, creating a strong incentive to over-invest, whereas the total cost benchmark assumes all costs to be variable, ignoring the investment risk. We propose theoretical, methodological, and operational advances to increase applicability of yardstick competition in energy regulation. In the proposed conditional yardstick regime capital is treated as a fixed input, and the local monopolies compete against the variable cost conditional on the fixed input. We develop a benchmarking method that can handle multiple outputs, heterogeneity, and shape constraints to ensure incentive compatibility. We discuss the real-world application of the proposed regime to the Finnish electricity distribution firms in 2016--2023. We argue that smarter regulation of network industries can contribute to lower risk premiums and help to achieve win-win solutions both in terms of reliability and affordability. [ABSTRACT FROM AUTHOR]

Research describes the molecular structure of the icosahedral carborane, the title compound using nuclear magnetic resonance studies. Data indicate that the complex exhibits flexibility in structural aspects, a fluxional in solution or a static structure in its endoterminal configuration.