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Feral swine (Sus scrofa) are an introduced species to the Great Smoky Mountains National Park (GSMNP), US, and serve as carriers of several diseases that are considered a threat to other wildlife, domestic animals, and humans. During 2013 and 2015, fecal samples from 67 feral swine from the GSMNP within both Tennessee and North Carolina, US, were opportunistically collected as part of a feral swine removal program and submitted to the University of Tennessee College of Veterinary Medicine, Knoxville, Tennessee, for parasite screening by centrifugal sugar flotation. Ten taxa from the phyla Acanthocephala, Apicomplexa, and Nematoda were identified: Ascaris spp., Strongylid-type spp., Capillaria spp., Trichuris suis, Metastrongylus spp., Macracanthorhynchus spp., Coccidia, Sarcocystis spp., and Cryptosporidium spp. In 98.5% of samples, at least one parasite was found. No differences in parasite prevalence or species diversity were noted based on state of collection (Tennessee or North Carolina), sex, or age. The high prevalence of gastrointestinal parasites in these feral swine, some of which are zoonotic, represents a potential public health risk as well as a concern for free-range swine farmers. [ABSTRACT FROM AUTHOR]

The Louisiana red swamp crayfish Procambarus clarkii is highly invasive. It is now common in Europe where it is causing problems to native wildlife and structural damage to habitats. Procambarus clarkii was first recorded in Britain in 1991 and is currently found in the Hampstead Heath ponds and Regents Canal in London, as well as a small lake 15 km outside of Greater London. This paper considers how conditions in Britain affect the life cycle, breeding habits and potential range expansion of P. clarkii. Results of trapping surveys are presented in an effort to map the current distribution of P. clarkii and predict which areas it could colonise in the future. The ecological impact of potential colonisation is discussed by considering the impact P. clarkii has in mainland Europe. It is concluded that P. clarkii is likely to spread from Regents Canal into the nearby Brent, Crane, Colne, Lee and Thames catchments within 50 years. This time would be reduced significantly if further deliberate or accidental introductions by humans occur since this is deemed a far greater risk than natural expansion. P. clarkii is expected to have a negative impact on aquatic ecosystems in Britain and therefore tighter enforcement is needed to slow the spread of this species.

Suggests current natural sciences model insufficient for rural sociology. Suggests reconceptualizing basic and applied social science to define non-natural phenomena with hierarchical characteristics including elements of agency or choice, social production and reproduction, learning, and creativity. Suggests using heuristic models and experimental methods in future inquiry. (TES)

Historically rural society has been viewed as being characterized by a concensus on a set of values unique to rural life. Data gathered from random samples of 15 communities in the intermountain West suggests, in general, that rurality and social stratification need to be integrated into a theory of values. (BR)

Using a tunable, narrow-bandwidth vacuum-ultraviolet source based on third-harmonic generation from excimer-pumped dye-laser radiation, the F³II[sub u]&lerr;X³∑[sup minus;, sub g] (1,0) photoabsorption cross sections of [sup 16]O[sub 2] and [sup 18]O[sub 2] have been recorded in high resolution. Rotational analyses have been performed and the resultant F(v = 1) term values fitted to the ³II Hamiltonian of Brown and Merer [J. Mol. Spectrosc. 74, 488 (1979)]. A large rotationless isotope effect is observed in the F(v=1) predissociation, wherein the Lorentzian linewidth component for [sup 18]O[sub 2] is a factor of ∼50 smaller than the corresponding [sup 16]O[sub 2] linewidth. This effect, a consequence of the nonadiabatic rotationless predissociation mechanism, is described using a coupled-channel treatment of the strongly Rydberg-valence-mixed ³II[sub u] states. Significant J, e/f-parity, and sublevel dependencies observed in the isotopic F(v = 1) rotational widths are found to derive from an indirect predissociation mechanism involving an accidental degeneracy with the E³∑[sup −, sub u] (v = 3) level, itself strongly predissociated by ³&Sum[sup − Rydberg-valence interactions, together with L-uncoupling (rotational) interactions between the Rydberg components of the F and E states. Transitions into the E(v =3) level are observed directly for the first time, specifically in the [sup 18]O[sub 2] spectrum. [ABSTRACT FROM AUTHOR]

New 16O2 photoabsorption cross-section measurements are presented for two bands near 88930 cm-1 and 90780 cm-1. We have assigned these bands as the (0,0) and (1,0) bands of the E′3Σu-←X3Σg- system, where the E′ state is a mixed state resulting from the coupling of 4pπu and 5pπu 3Σu- Rydberg states with the lowest 3Σu- valence state. In contrast to the E3Σu-←X3Σg- bands seen at lower energies, these bands show resolved rotational structure. Spectroscopic parameters for the upper levels have been derived using an effective Hamiltonian and cross-section band models. The observed levels are perturbed by spin-orbit interactions with nearby levels (v=1 and 2) of the 4pπu D′3Σu+ Rydberg state. In addition, transitions to the v=2 level of the perturber state have been observed near 90920 cm-1. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A comprehensive vibronic assignment of the 3Πu states in the energy region approaching the first ionization threshold of O2 is presented for the first time. Measurements of seventeen 3Πu←X 3Σ-g bands in the 85 800–93 000 cm-1 region of the ground-state photoabsorption spectra of 16O2 and 18O2 at 79 K are reported, including six bands in the spectrum of 18O2 for the first time. Irregularities in vibrational spacings and in the extent of broadening by predissociation are shown to result from Rydberg-valence interactions. The observed transitions have been assigned, using semiempirical modeling of the 3Πu Rydberg-valence interactions based on the coupled-channel Schrödinger equations technique, to two vibrational progressions with upper states which we call F 3Πu and F′ 3Πu. The F and F′ states are formed from the avoided crossings of the npσu (n=3–5) Rydberg potential-energy curves by the lowest repulsive 3Πu valence potential-energy curve. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

New high-resolution measurements of the O2 photoabsorption cross section in the 1147–1155 Å region are presented. The observation of three previously-unreported narrow lines in a band near 1148 Å has enabled unambiguous assignment of the band to a 1Πu←X3Σg- transition which gains strength through a spin-orbit interaction with the upper state of a 3Πu←X3Σg- transition appearing at 1153 Å. Other lines in the 1148 Å band are broadened by predissociation through a heterogeneous interaction with a nearly energetically coincident 1Δu level. The states, labelled h1Πu, F3Πu and i1Δu, are predominantly of 4pλ Rydberg molecular orbital configurations although there are indications that the Πu states interact strongly with valence states of the same symmetry. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]