583 research outputs found

    A History of Appalachia

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    Richard Drake has skillfully woven together the various strands of the Appalachian experience into a sweeping whole. Touching upon folk traditions, health care, the environment, higher education, the role of blacks and women, and much more, Drake offers a compelling social history of a unique American region. The Appalachian region, extending from Alabama in the South up to the Allegheny highlands of Pennsylvania, has historically been characterized by its largely rural populations, rich natural resources that have fueled industry in other parts of the country, and the strong and wild, undeveloped land. The rugged geography of the region allowed Native American societies, especially the Cherokee, to flourish. Early white settlers tended to favor a self-sufficient approach to farming, contrary to the land grabbing and plantation building going on elsewhere in the South. The growth of a market economy and competition from other agricultural areas of the country sparked an economic decline of the region’s rural population at least as early as 1830. The Civil War and the sometimes hostile legislation of Reconstruction made life even more difficult for rural Appalachians. Recent history of the region is marked by the corporate exploitation of resources. Regional oil, gas, and coal had attracted some industry even before the Civil War, but the postwar years saw an immense expansion of American industry, nearly all of which relied heavily on Appalachian fossil fuels, particularly coal. What was initially a boon to the region eventually brought financial disaster to many mountain people as unsafe working conditions and strip mining ravaged the land and its inhabitants. A History of Appalachia also examines pockets of urbanization in Appalachia. Chemical, textile, and other industries have encouraged the development of urban areas. At the same time, radio, television, and the internet provide residents direct links to cultures from all over the world. The author looks at the process of urbanization as it belies commonly held notions about the region’s rural character. Named a Choice Outstanding Academic Title for 2002.https://uknowledge.uky.edu/upk_appalachian_studies/1022/thumbnail.jp

    Conformational Preferences of 3-(Dimethylazinoyl)propanoic Acid as a Function of pH and Solvent; Intermolecular versus Intramolecular Hydrogen Bonding

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    The conformational equilibrium of 3-(dimethylazinoyl)propanoic acid (DMAPA, azinoyl = N^+(O^−) has a weak pH-dependence in D_2O, with a slight preference for trans in alkaline solutions. The acid ionization constants of the protonated amine oxide and carboxylic functional groups as determined by NMR spectroscopy were 7.9 × 10^(−4) and 6.3 × 10^(−6), respectively. The corresponding value of K_1/K_2 of 1.3 × 10^2 is not deemed large enough to provide experimental NMR evidence for a significant degree of intramolecular hydrogen bonding in D_2O. Conformational preferences of DMAPA are mostly close to statistical (gauche/trans = 2/1) in other protic solvents, e.g., alcohols. However, the un-ionized form of DMAPA appears to be strongly intramolecularly hydrogen-bonded and gauche in aprotic solvents

    The MUSE Hubble Ultra Deep Field Survey X. Lyα\alpha Equivalent Widths at 2.9<z<6.62.9 < z < 6.6

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    We present rest-frame Lyα\alpha equivalent widths (EW) of 417 Lyα\alpha emitters (LAEs) detected with Multi Unit Spectroscopic Explorer (MUSE) on the Very Large Telescope (VLT) at 2.9<z<6.62.9 < z < 6.6 in the Hubble Ultra Deep Field. Based on the deep MUSE spectroscopy and ancillary Hubble Space Telescope (HST) photometry data, we carefully measured EW values taking into account extended Lyα\alpha emission and UV continuum slopes (ÎČ\beta). Our LAEs reach unprecedented depths, both in Lyα\alpha luminosities and UV absolute magnitudes, from log(LLyαL_{\rm Ly\alpha}/erg s−1^{-1}) ∌\sim41.0 to 43.0 and from Muv ∌\sim -16 to -21 (0.01-1.0 Lz=3∗L^{*}_{\rm z=3}). The EW values span the range of ∌\sim 5 to 240 \AA\ or larger, and their distribution can be well fitted by an exponential law N=N0N = N_{\rm 0} exp(−-EW/w0w_{\rm 0}). Owing to the high dynamic range in Muv, we find that the scale factor, w0w_{\rm 0}, depends on Muv in the sense that including fainter Muv objects increases w0w_{\rm 0}, i.e., the Ando effect. The results indicate that selection functions affect the EW scale factor. Taking these effects into account, we find that our w0w_{\rm 0} values are consistent with those in the literature within 1σ1\sigma uncertainties at 2.9<z<6.62.9 < z < 6.6 at a given threshold of Muv and LLyαL_{\rm Ly\alpha}. Interestingly, we find 12 objects with EW >200>200 \AA\ above 1σ1\sigma uncertainties. Two of these 12 LAEs show signatures of merger or AGN activity: the weak CIV λ1549\lambda 1549 emission line. For the remaining 10 very large EW LAEs, we find that the EW values can be reproduced by young stellar ages (<100< 100 Myr) and low metallicities (â‰Č0.02\lesssim 0.02 Z⊙Z_{\rm \odot}). Otherwise, at least part of the Lyα\alpha emission in these LAEs needs to arise from anisotropic radiative transfer effects, fluorescence by hidden AGN or quasi-stellar object activity, or gravitational cooling.Comment: 22 pages, 12 figures, 9 tables, accepted for publication in A&A (MUSE UDF Series Paper X

    Wild Food:Plants, Fish and Small Animals on the Menu for Early Holocene Populations at al-Khiday, Central Sudan

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    Al Khiday, located on the bank of the White Nile in Sudan, offers an exceptionally preserved stratigraphic sequence, providing a unique opportunity to use organic residue analysis to investigate diet and subsistence over the full course of the Khartoum Mesolithic together with possible continuity or change into the Early Neolithic, a period of nearly 3000 years (8900-6000 cal BP). Whilst the vast and diverse Mesolithic fish assemblage indicates a strong reliance on products from aquatic habitats, floodplains, vegetated marshes and open water, results from the lipid residue analysis suggest that the fish were not cooked in the pots, likely being consumed in other ways. Rather, pots were more specialised in processing plants, wild grasses, leafy plants and sedges, confirmed by experimental analysis, and for the first time, providing direct chemical evidence for plant exploitation in the Khartoum Mesolithic. Non-ruminant fauna, such as warthog and low lipid-yielding reptiles such as Adanson’s mud turtle and Nile monitor lizard, which were found in significant numbers at al-Khiday, were also cooked in pots. There is little evidence for the processing of wild ruminants in the pots, suggesting either that ruminant species were not routinely hunted, or, that large wild fauna may have been cooked in different ways, possibly grilled over fires. These data suggest sophisticated economic strategies by sedentary people likely exploiting their ecological niche to the fullest. Pottery use changes considerably in the Early Neolithic, with ruminant products being more routinely processed in pots, and while the exploitation of domesticates cannot be confirmed by a small faunal assemblage, some dairying does take place. In summary, our results provide valuable information on Early and Middle Holocene lifeways in central Sudan

    Close to the Dredge: Precise X-ray C and N Abundances in lambda Andromeda and its Precocious RGB Mixing Problem

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    Chandra LETG+HRC-S and XMM-Newton RGS spectra of H-like C and N formed in the corona of the lambda And primary star, a mildly metal-poor G8 III-IV first ascent giant that completed dredge-up ~50 Myr ago, have been used to make a precise measurement of its surface C/N ratio. We obtain the formal result [C/N]=0.03+/-0.07, which is typical of old disk giants and in agreement with standard dredge-up theory for stars of about 1 M_sun or lower. In contrast, these stars as a group, including lambda And, have 12C/13C ~< 20, which is much lower than standard model predictions. We show that the abundances of the old disk giants are consistent with models including thermohaline mixing that begins at the red giant branch luminosity function "bump". Instead, lambda And indicates that the 12C/13C anomaly can be present immediately following dredge-up, contrary to current models of extra mixing on the red giant branch.Comment: To appear in the Astronomical Journa

    Pots, plants and animals:broad-spectrum subsistence strategies in the Early Neolithic of the Moroccan Rif region

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    The transition from hunter-gathering to food-producing societies in the Mediterranean zone of north Africa was complex and variable, likely influenced by local ecological conditions as well as the socio-economic origins of the population. The adoption of domestic plants and animals was piecemeal, with hunting and gathering continuing as an important part of local subsistence strategies. Here, we investigate the timing and extent of the adoption of agricultural practices, namely herding and cultivation, in three diverse coastal and inland Early Neolithic sites in the Mediterranean Maghreb region, namely Ifri Oudadane, Ifri n’Etsedda and Hassi Ouenzga. Results from absorbed lipid residues extracted from 306 potsherds from these sites are correlated with information from faunal and archaeobotanical assemblages. Our findings suggest that agricultural practices, regarded as being of Neolithic origin, were never fully adopted in the Maghreb but rather that these farmer/foragers adopted a range of strategies including low-level food production (exploiting cereals and animal products, including meat and milk), gathering of wild plants and marine shellfish, and hunting both small and large sized game. These broad-spectrum farmer/foragers were clearly both flexible and resourceful and likely adapted their subsistence practices to maximise resource availability in an increasingly unpredictable environment

    Recovery of 29-s Oscillations in HST/FOS Eclipse Observations of the Cataclysmic Variable UX Ursae Majoris

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    [abridged abstract] Low amplitude (~=0.5%) 29-s oscillations have been detected in HST/FOS eclipse observations of the nova-like cataclysmic variable UX UMa. These are the same dwarf nova-type oscillations that were originally discovered in this system by Warner & Nather in 1972. The oscillations are sinusoidal to within the small observational errors and undergo an approximately -360 degree phase shift during eclipses. Their amplitudes are highest at pre-eclipse orbital phases and exhibit a rather gradual eclipse whose shape is roughly similar to UX~UMa's overall light curve. Oscillation spectra derived from pre-eclipse data segments are extremely blue, whereas mid-eclipse oscillation spectra are much redder. We suggest that the ultimate source of the oscillations is a hot, compact region near disk center, but that a significant fraction of the observed, modulated flux is due to reprocessing of the light emitted by this source in the accretion disk atmosphere. The compact source is occulted at orbital phases near mid-eclipse, leaving only part of the more extended reprocessing region(s) to produce the weak oscillations that persist even at conjunction. The highly sinusoidal oscillation pulse shape does not permit the identification of the compact component in this model with emission produced by a rotating disturbance in the inner disk or in an equatorial boundary layer, and a standard intermediate polar model can also be ruled out. A model invoking magnetically controlled accretion onto differentially rotating WD surface layers may be viable, but needs more theoretical work.Comment: 28 pages, including 9 figures; to appear in the ApJ (Vol. 499

    Mars Aeronomy Observer: Report of the Science Working Team

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    The Mars Aeronomy Observer (MAO) is a candidate follow-on mission to Mars Observer (MO) in the Planetary Observer Program. The four Mariner and two Viking spacecraft sent to Mars between 1965 and 1976 have provided a wealth of information concerning Martian planetology. The Mars Observer, to be launched in 1990, will build on their results by further examining the elemental and mineralogical composition of the surface, the strength and multipolar composition of the planetary magnetic field, the gravitational field and topography, and the circulation of the lower atmosphere. The Mars Aeronomy Observer is intended to address the last major aspects of Martian environment which have yet to be investigated: the upper atmosphere, the ionsphere, and the solar wind interaction region

    Molecular Detection of Invasive Species in Heterogeneous Mixtures Using a Microfluidic Carbon Nanotube Platform

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    Screening methods to prevent introductions of invasive species are critical for the protection of environmental and economic benefits provided by native species and uninvaded ecosystems. Coastal ecosystems worldwide remain vulnerable to damage from aquatic species introductions, particularly via ballast water discharge from ships. Because current ballast management practices are not completely effective, rapid and sensitive screening methods are needed for on-site testing of ships in transit. Here, we describe a detection technology based on a microfluidic chip containing DNA oligonucleotide functionalized carbon nanotubes. We demonstrate the efficacy of the chip using three ballast-transported species either established (Dreissena bugensis) or of potential threat (Eriocheir sinensis and Limnoperna fortuneii) to the Laurentian Great Lakes. With further refinement for on-board application, the technology could lead to real-time ballast water screening to improve ship-specific management and control decisions
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