Bats of Hot Springs National Park, Arkansas

A survey was conducted from June 1982 through January 1987 to determine the occurrence of bat species in Hot Springs National Park, Garland County, Arkansas; an area of approximately 2025 hectares. A total of 309 bats in the families Molossidae and Vespertilionidae were captured. Species represented included: Eptesicus fuscus, Lasiurus borealis, Lasiurus cinereus, Nycticeius humeralis, Pipistrellus subflavus, and Tadarida brasiliensis cynocephala

Abandoned Mine Fauna of the Ouachita Mountains, Arkansas: Vertebrate Taxa

Numerous visits, over the past four years, of 27 abandoned mines in the Ouachita Mountains of Arkansas revealed that the mines are serving as hibernacula, breeding sites, and permanent or temporary habitats for numerous vertebrates. The following species were observed either directly or by sign: Class Amphibia, Order Urodela — Eurycea multiplicata, Desmognathus brimleyorum, Plethodon caddoensis, P. glutinosus. Order Anura — Gastrophyrne carolinensis, Rana palustris, R. catesbeiana. Class Reptilia, Order Squamata, Suborder Serpentes — Thamnophis proximus, Diadophis punctatus, Elaphe obsoleta, Nerodia erythrogaster, Agkistrodon contortrix. Class Aves, Order Passeriformes--Sayornis phoebe. Order Strigiformes — Otus asio. Class Mammalia, Order Marsupialia —Didelphis virginiana. order Chiroptera — Lasiurus borealis, L seminolis, Myotis lucifugus, M. keenii, M. austroriparius, Eptesicus fuscus, Lasionycteris noctivagans, Pipistrellus subflavus. Order Rodentia—Neotoma floridana, Peromyscus attwateri. Order Carnivora—Procyon lotor, Ursus americanus

Bats of the Ouachita Mountains

A survey was conducted from June, 1982 through January, 1989 to determine the occurrence of bat species in the Ouachita Mountain region of west-central Arkansas and southeastern Oklahoma, with emphasis on censusing lands managed by the USDA Forest Service, Ouachita National Forest. Seven genera and 13 species of bats in the families Vespertilionidae and Molossidae were captured. Species represented included: Eptesicus fuscus, Lasionycteris noctivagans, Lasiurus borealis, Lasiurus cinereus, Lasiurus seminolus, Myotis austroriparius, Myotis keenii, Myotis leibii, Myotis lucifugus, Myotissodalis, Nycticeius humeralis, Pipistrellus subflavus, and Tadarida brasiliensis cynocephala

Distribution and Status of the Brazilian Free-tailed Bat (Tadarida brasiliensis cynocephala) in Arkansas

Investigations of building infestations, mist netting activities, and specimens submitted to the Arkansas Department of Health document the Brazilian free-tailed bat to be found in 14 Arkansas counties. Both overwintering and maternity colonies were examined. Numbers of individuals ranged from one to several thousand

Distribution of LeConte\u27s Free-tailed Bat (Tadarida brasiliensis cynocephala) in Arkansas, with Notes on Reproduction and Natural History

During the past 20 years (1982-2001) we have studied the biology, occurrence and distribution of LeConte\u27s (Brazilian) free-tailed bat, Tadarida brasiliensis cynocephala, in Arkansas. Colonies and individuals were reported from man made structures only. Four new county records have been documented since 1988, extending the range from the central part of the state to Arkansas\u27s northern-most tier of counties. Numerous nuisance maternity colonies were investigated during exclusion activities and one, year-round colony provided the majority of reproductive data. A total of 152 free-tailed bats was submitted to the Arkansas Department of Health Rabies Laboratory (1982-2001); most during February through April, a period that corresponded to annual mating activity. Pregnant bats had single embryos only in the right uterine horn and parturition occurred in mid-June. Seven specimens tested positive for rabies

Plutonium Migration during the Leaching of Cemented Radioactive Waste Sludges

One of the most challenging components of the UK nuclear legacy is Magnox sludge, arising from the corrosion of Mg alloy-clad irradiated metallic U fuel that has been stored in high pH ponds. The sludges mainly comprise Mg hydroxide and carbonate phases, contaminated with fission products and actinides, including Pu. Cementation and deep geological disposal is one option for the long-term management of this material, but there is a need to understand how Pu may be leached from the waste, if it is exposed to groundwater. Here, we show that cemented Mg(OH)2 powder prepared with Pu(IV)aq is altered on contact with water to produce a visibly altered ‘leached zone’, which penetrates several hundred microns into the sample. In turn, this zone shows slow leaching of Pu, with long-term leaching rates between 1.8–4.4 × 10−5% of total Pu per day. Synchrotron micro-focus X-ray fluorescence mapping identified decreased Pu concentration within the ‘leached zone’. A comparison of micro-focus X-ray absorption spectroscopy (µ-XAS) spectra collected across both leached and unleached samples showed little variation, and indicated that Pu was present in a similar oxidation state and coordination environment. Fitting of the XANES spectra between single oxidation state standards and EXAFS modeling showed that Pu was present as a mixture of Pu(IV) and Pu(V). The change in Pu oxidation from the stock solution suggests that partial Pu oxidation occurred during sample ageing. Similarity in the XAS spectra from all samples, with different local chemistries, indicated that the Pu oxidation state was not perturbed by macro-scale variations in cement chemistry, surface oxidation, sample aging, or the leaching treatment. These experiments have demonstrated the potential for leaching of Pu from cementitious waste forms, and its underlying significance requires further investigation

Plutonium Migration during the Leaching of Cemented Radioactive Waste Sludges

One of the most challenging components of the UK nuclear legacy is Magnox sludge, arising from the corrosion of Mg alloy-clad irradiated metallic U fuel that has been stored in high pH ponds. The sludges mainly comprise Mg hydroxide and carbonate phases, contaminated with fission products and actinides, including Pu. Cementation and deep geological disposal is one option for the long-term management of this material, but there is a need to understand how Pu may be leached from the waste, if it is exposed to groundwater. Here, we show that cemented Mg(OH)2 powder prepared with Pu(IV)aq is altered on contact with water to produce a visibly altered ‘leached zone’, which penetrates several hundred microns into the sample. In turn, this zone shows slow leaching of Pu, with long-term leaching rates between 1.8–4.4 × 10−5% of total Pu per day. Synchrotron micro-focus X-ray fluorescence mapping identified decreased Pu concentration within the ‘leached zone’. A comparison of micro-focus X-ray absorption spectroscopy (µ-XAS) spectra collected across both leached and unleached samples showed little variation, and indicated that Pu was present in a similar oxidation state and coordination environment. Fitting of the XANES spectra between single oxidation state standards and EXAFS modeling showed that Pu was present as a mixture of Pu(IV) and Pu(V). The change in Pu oxidation from the stock solution suggests that partial Pu oxidation occurred during sample ageing. Similarity in the XAS spectra from all samples, with different local chemistries, indicated that the Pu oxidation state was not perturbed by macro-scale variations in cement chemistry, surface oxidation, sample aging, or the leaching treatment. These experiments have demonstrated the potential for leaching of Pu from cementitious waste forms, and its underlying significance requires further investigation

A Bacterial Acetyltransferase Destroys Plant Microtubule Networks and Blocks Secretion

The eukaryotic cytoskeleton is essential for structural support and intracellular transport, and is therefore a common target of animal pathogens. However, no phytopathogenic effector has yet been demonstrated to specifically target the plant cytoskeleton. Here we show that the Pseudomonas syringae type III secreted effector HopZ1a interacts with tubulin and polymerized microtubules. We demonstrate that HopZ1a is an acetyltransferase activated by the eukaryotic co-factor phytic acid. Activated HopZ1a acetylates itself and tubulin. The conserved autoacetylation site of the YopJ / HopZ superfamily, K289, plays a critical role in both the avirulence and virulence function of HopZ1a. Furthermore, HopZ1a requires its acetyltransferase activity to cause a dramatic decrease in Arabidopsis thaliana microtubule networks, disrupt the plant secretory pathway and suppress cell wall-mediated defense. Together, this study supports the hypothesis that HopZ1a promotes virulence through cytoskeletal and secretory disruption