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A 2018 workshop on the White Mountain Apache Tribe lands in Arizona examined ways to enhance investigations into cultural property crime (CPC) through applications of rapidly evolving methods from archaeological science. CPC (also looting, graverobbing) refers to unauthorized damage, removal, or trafficking in materials possessing blends of communal, aesthetic, and scientific values. The Fort Apache workshop integrated four generally partitioned domains of CPC expertise: (1) theories of perpetrators’ motivations and methods; (2) recommended practice in sustaining public and community opposition to CPC; (3) tactics and strategies for documenting, investigating, and prosecuting CPC; and (4) forensic sedimentology—uses of biophysical sciences to link sediments from implicated persons and objects to crime scenes. Forensic sedimentology served as the touchstone for dialogues among experts in criminology, archaeological sciences, law enforcement, and heritage stewardship. Field visits to CPC crime scenes and workshop deliberations identified pathways toward integrating CPC theory and practice with forensic sedimentology’s potent battery of analytic methods.
The shock between the colliding winds in binary systems containing two massive stars accelerates particles to relativistic energies. These energetic particles can produce observable non-thermal radiation from the radio to γ-rays. The important physical processes in such systems are very similar to those we have proposed for non-thermal emissions from single hot stars, which have shocks generated by instabilities in the radiatively driven stellar winds. This paper discusses the theory and observations of non-thermal radiation in the radio, X-ray, and γ-ray regions from both single stars and massive binaries. Similarities and differences between the two types of systems are outlined. We discuss two important physical effects that apparently have been neglected in previous theoretical work on colliding wind binaries.
Although we now know of quite a few WR-O star binary systems, only HD 193793 is well studied across the entire electromagnetic spectrum. Hence it affords us the best opportunity to test various models for the system against a wealth of observational data. In this paper we present the results of 8 years of monitoring the radio flux density from HD 193793 with the VLA. This database is unique both in terms of its dense coverage of an entire binary cycle and because it extends the radio coverage to 2 cm wavelength, a shorter wavelength than previously available. With this data we are able to simultaneously solve for the time dependent attenuation in the system and the intrinsic radio luminosity. The standard model of spherically symmetric colliding winds faces severe difficulties in explaining the observations. We conclude that the radio data are most readily interpreted in the context of a WR star wind which is confined to a disk. A disk model for the WR wind also provides a natural explanation for the sudden formation of dust just after periastron.
Long-range temporal choices are built into contemporary policy-making, with policy decisions having consequences that play out across generations. Decisions are made on behalf of the public who are assumed to give much greater weight to their welfare than to the welfare of future generations. The paper investigates this assumption. It briefly discusses evidence from sociological and economic studies before reporting the findings of a British survey of people's intergenerational time preferences based on a representative sample of nearly 10,000 respondents. Questions focused on two sets of policies: (i) health policies to save lives and (ii) environmental policies to protect against floods that would severely damage homes, businesses and other infrastructure. For both sets of policies, participants were offered a choice of three policy options, each bringing greater or lesser benefits to their, their children's and their grandchildren's generations. For both saving lives and protecting against floods, only a minority selected the policy that most benefited their generation; the majority selected policies bringing equal or greater benefits to future generations. Our study raises questions about a core assumption of standard economic evaluation, pointing instead to concern for future generations as a value that many people hold in common.
The spherical aberration in the primary mirror of the Hubble Space Telescope causes more than 80% of the light from a point source to be spread into a halo of radius of 2–3 arcsec. The point spread function (PSF) is both time variant (resulting from spacecraft jitter and desorption of the secondary mirror support structure) and space variant (owing to the Cassegrain repeater optics in the Wide Field / Planetary Camera). A variety of image restoration algorithms have been utilized on HST data with some success, although optimal restorations require better modeling of the PSF and the development of efficient restoration algorithms that accommodate a spacevariant PSF. The first HST servicing mission (December 1993) will deploy a corrective optics system for the Faint Object Camera and the two spectrographs and a second generation WF/PC with internal corrective optics. As simulations demonstrate, however, the restoration algorithms developed now for aberrated images will be very useful for removing the remaining diffraction features and optimizing dynamic range in post-servicing mission data.
In late February and early March 2002, an archaeological watching brief at Lynford Quarry, Mundford, Norfolk revealed a palaeochannel with a dark organic fill containing in situ mammoth remains and associated Mousterian stone tools and debitage buried under 2–3 m of bedded sands and gravels. Well-preserved in situ Middle Palaeolithic open air sites are very unusal in Europe and exceedingly rare within a British context. As such, the site was identified as being of national and international importance, and was subsequently excavated by the Norfolk Archaeological Unit with funding provided by English Heritage through the Aggregates Levy Sustainability Fund.
This report presents some of the initial results of the excavation. It sets out how the site was excavated, outlines the stratigraphic sequence for the site, and presents some provisional findings of the excavation based on the results of the assessment work carried out by project specialists and Norfolk Archaeological Unit staff.
To examine the use of vitamin D supplements during infancy among the participants in an international infant feeding trial.
Information about vitamin D supplementation was collected through a validated FFQ at the age of 2 weeks and monthly between the ages of 1 month and 6 months.
Infants (n 2159) with a biological family member affected by type 1 diabetes and with increased human leucocyte antigen-conferred susceptibility to type 1 diabetes from twelve European countries, the USA, Canada and Australia.
Daily use of vitamin D supplements was common during the first 6 months of life in Northern and Central Europe (>80 % of the infants), with somewhat lower rates observed in Southern Europe (>60 %). In Canada, vitamin D supplementation was more common among exclusively breast-fed than other infants (e.g. 71 % v. 44 % at 6 months of age). Less than 2 % of infants in the USA and Australia received any vitamin D supplementation. Higher gestational age, older maternal age and longer maternal education were study-wide associated with greater use of vitamin D supplements.
Most of the infants received vitamin D supplements during the first 6 months of life in the European countries, whereas in Canada only half and in the USA and Australia very few were given supplementation.
Both HIV infection and high levels of early life stress (ELS) have been related to abnormalities in frontal-subcortical structures, yet the combined effects of HIV and ELS on brain structure and function have not been previously investigated. In this study we assessed 49 non-demented HIV-seropositive (HIV+) and 47 age-matched HIV-seronegative healthy control (HC) adults. Levels of ELS exposure were quantified and used to define four HIV-ELS groups: HC Low-ELS (N = 20); HC High-ELS (N = 27); HIV+ Low-ELS (N = 24); HIV+ High-ELS (N = 25). An automated segmentation tool measured volumes of brain structures known to show HIV-related or ELS-related effects; a brief neurocognitive battery was administered. A significant HIV-ELS interaction was observed for amygdala volumes, which was driven by enlargements in HIV+ High-ELS participants. The HIV+ High-ELS group also demonstrated significant reductions in psychomotor/processing speed compared with HC Low-ELS. Regression analyses in the HIV+ group revealed that amygdala enlargements were associated with higher ELS, lower nadir CD4 counts, and reduced psychomotor/processing speed. Our results suggest that HIV infection and high ELS interact to increase amygdala volume, which is associated with neurocognitive dysfunction in HIV+ patients. These findings highlight the lasting neuropathological influence of ELS and suggest that high ELS may be a significant risk factor for neurocognitive impairment in HIV-infected individuals. (JINS, 2012, 19, 1–12)
Tourism development is one of the main contemporary drivers of habitat loss and fragmentation within the Caribbean Islands biodiversity hotspot. In Saint Lucia, construction of a hotel and golf course within coastal dry forest is directly threatening the largest known subpopulation of the Endangered White-breasted Thrasher Ramphocinclus brachyurus. Understanding how the species is responding to ongoing landscape change and identifying priority sites for conservation are imperative for planning its long-term conservation. In this study, a four year White-breasted Thrasher monitoring dataset (2006–2009) and landscape-scale environmental variables were used to: a) identify, characterise and map spatio-temporal patterns of White-breasted Thrasher encounter rate (an abundance proxy) within and outside the tourist development site; b) determine landscape-scale environmental variables that influence such patterns, and c) produce an island-wide predictive map of potentially suitable habitat. Observed patterns in encounter rates within and outside the development site were consistent with thrashers being displaced from cleared areas of forest and crowding into intact forest patches to the north and west of the golf course. A year after the period of the most extensive habitat clearance, White-breasted Thrasher numbers declined markedly leading to a 55% reduction in encounter rate within the development site over the four years of the study. The habitat suitability model predicted that a range of sites outside of the known geographic range of the thrasher are potentially suitable, some of which merit further surveys for potentially undetected populations. Given these findings, it is vital that patches of suitable dry forest adjacent to the tourist development are protected and contiguous natural habitat inside the tourist development is preserved.
This paper describes the fabrication, and structural and electrical characterization of a new, aerosol-nanocrystal floating-gate FET, aimed at non-volatile memory (NVM) applications. This aerosol- nanocrystal NVM device features program/erase characteristics comparable to conventional stacked gate NVM devices, excellent endurance (>105 P/E cycles), and long-term non-volatility in spite of a thin bottom oxide (55-60Å). In addition, a very simple fabrication process makes this aerosol-nanocrystal NVM device a potential candidate for low cost NVM applications.
Carbon overcoat films are used extensively in thin film disk applications to provide wear resistance. A nano-indentation technique and wafer curvature measurements have been used to study the mechanical properties of carbon films sputtered under various processing conditions. Specifically, the effects of substrate/target spacing, power, pressure, and substrate bias have been studied for films sputtered in an argon plasma. The relationship of these properties to contact start-stop performance of hydrocarbon lubricated disks is further described. The frictional performance during the test can be related to film hardness, while the durability can be affected by the residual film stress.
For the first time, surface acoustic waves (SAWs) were used to study the lattice relaxation of metastable defects. A persistent increase of as much as 0.4% of the SAW velocity at low temperatures was observed after illumination of LT-GaAs; this increase could be quenched by annealing at 120–130°K. This behaviour is caused by the metastable transition of EL2-like AsGa defects and constitutes the direct experimental proof of the illumination induced large lattice relaxation of this defect.
The effect of residual stress on the scratch adhesion critical load has been measured for sputtered tantalum films. In this single metallurgical system, six different failure modes could be observed, ranging from ductile ploughing to extensive spallation. For tantalum films deposited on silicon substrates, a 15% decrease in critical load was observed as the film residual stress increased from -1.1 GPa to +1.0 GPa. A larger percentage decrease (50%) was observed for films deposited on softer AIMg/NiP substrates. Film spallation was more extensive for films deposited over a thin carbon layer and for these films critical loads increased slightly with film stress. These results are substantially in contradiction with existing quantitative models for the scratch adhesion test and indicate that failure by shear at the film-substrate interface can be more important than failure by compressive buckling.
Three samples of self-assembled In0.44Ga0.56As quantum dots (QDs) grown on (001) GaAs by molecular beam epitaxy (MBE) were studied using atomic force microscopy (AFM) and high-resolution transmission electron microscopy (TEM) in order to characterize the height, faceting, and densities of the QDs. The cross-sectional TEM images show both pyramidal dots and dots with multiple side facets. Multiple faceting has been observed only in dots more than 8.5 nm in height and allows increased dot volume without a substantial increase in base area. Addition of a GaAs capping layer is found to increase the diameter of the QDs from roughly 40 nm to as much as 200 nm. The areal QD density is found to vary up to 50 % over the central 2 cm x 2 cm section of wafer and by as much as 23 % on a length scale of micrometers.