Biodiversity of Parasitic Hymenoptera Across Sky Islands of Arkansas, United States.

Sky islands are often areas of endemism and high species diversity around the world. In central North America, the Ozark and Ouachita Highlands contain numerous modestly high elevational islands that are slightly cooler and wetter than surrounding lowlands and these areas are known to contain many unique species. We studied parasitic Hymenoptera biodiversity on three sky islands in Arkansas, both in canopy and understory strata of mature post oak forests.

Opposing global change drivers counterbalance trends in breeding North American monarch butterflies.

Many insects are in clear decline, with monarch butterflies (Danaus plexippus) drawing particular attention as a flagship species. It is well documented that, among migratory populations, numbers of overwintering monarchs have been falling across several decades, but trends among breeding monarchs are less clear. Here, we compile >135,000 monarch observations between 1993 and 2018 from the North American Butterfly Association's annual butterfly count to examine spatiotemporal patterns and potential drivers of adult monarch relative abundance trends across the entire breeding range in eastern and western North America.

Complex life histories predispose aphids to recent abundance declines.

Many animals change feeding habits as they progress through life stages, exploiting resources that vary in space and time. However, complex life histories may bring new risks if rapid environmental change disrupts the timing of these switches. Here, we use abundance times series for a diverse group of herbivorous insects, aphids, to search for trait and environmental characteristics associated with declines.

Recent climate change is creating hotspots of butterfly increase and decline across North America.

Some insect populations are experiencing dramatic declines, endangering the crucial ecosystem services they provide. Yet, other populations appear robust, highlighting the need to better define patterns and underlying drivers of recent change in insect numbers. We examined abundance and biodiversity trends for North American butterflies using a unique citizen-science dataset that has recorded observations of over 8 million butterflies across 456 species, 503 sites, nine ecoregions, and 26 years.

No net insect abundance and diversity declines across US Long Term Ecological Research sites.

Recent reports of dramatic declines in insect abundance suggest grave consequences for global ecosystems and human society. Most evidence comes from Europe, however, leaving uncertainty about insect population trends worldwide. We used >5,300 time series for insects and other arthropods, collected over 4-36 years at monitoring sites representing 68 different natural and managed areas, to search for evidence of declines across the United States.

Potential for Reclamation of Abandoned Gas Wells to Restore Ecosystem Services in the Fayetteville Shale of Arkansas.

Unconventional oil and gas (UOG) drilling has expanded rapidly across the United States, including in the Fayetteville Shale formation in north-central Arkansas where drilling began in 2004. As one of the oldest regions of UOG activity in the United States, this area has experienced significant land-use changes, specifically development of natural habitat and agricultural land for gas infrastructure. In recent years, drilling of new wells has stopped and production has declined.

Cut points of the Actigraph GT9X for moderate and vigorous intensity physical activity at four different wear locations.

Accelerometer cut points are an important consideration for distinguishing the intensity of activity into categories such as moderate and vigorous. It is well-established in the literature that these cut points depend on a variety of factors, including age group, device, and wear location. The Actigraph GT9X is a newer model accelerometer that is used for physical activity research, but existing cut points for this device are limited since it is a newer device.

Tracking Steps on Apple Watch at Different Walking Speeds.

Key Points: QUESTION: How accurate are the step counts obtained from Apple Watch?

Findings: In this validation study, video steps vs. Apple Watch steps (mean ± SD) were 2965 ± 144 vs. 2964 ± 145 steps; P < 0.

A Comparison of the Impacts of Wind Energy and Unconventional Gas Development on Land-use and Ecosystem Services: An Example from the Anadarko Basin of Oklahoma, USA.

The United States energy industry is transforming with the rapid development of alternative energy sources and technological advancements in fossil fuels. Two major changes include the growth of wind turbines and unconventional oil and gas. We measured land-use impacts and associated ecosystem services costs of unconventional gas and wind energy development within the Anadarko Basin of the Oklahoma Woodford Shale, an area that has experienced large increases in both energy sectors.

Habitat Modification by the Leaf-Cutter Ant, Atta cephalotes, and Patterns of Leaf-Litter Arthropod Communities.

Ecosystem engineers are profoundly important in many biological communities. A Neotropical taxonomic group considered to have engineering effects is the Formicidae (ants). Leaf-cutter ants (LCAs), in particular, which form extensive colonies of millions of individuals, can be important ecosystem engineers in these environments.

Seed dispersal of in the past and the present: Evidence for a generalist evolutionary strategy.

Several North American trees are hypothesized to have lost their co-evolved seed disperser during the late-Pleistocene extinction and are therefore considered anachronistic. We tested this hypothesis for the American persimmon () by studying the effects of gut passage of proposed seed dispersers on seedling survival and growth, natural fruiting characteristics, and modern animal consumption patterns. We tested gut passage effects on persimmon seeds using three native living species, the raccoon (), Virginia opossum (), and coyote (), and two Pleistocene analogs; the Asian elephant () and alpaca ().

Habitat loss and modification due to gas development in the Fayetteville shale.

Hydraulic fracturing and horizontal drilling have become major methods to extract new oil and gas deposits, many of which exist in shale formations in the temperate deciduous biome of the eastern United States. While these technologies have increased natural gas production to new highs, they can have substantial environmental effects. We measured the changes in land use within the maturing Fayetteville Shale gas development region in Arkansas between 2001/2002 and 2012.

Bison grazing increases arthropod abundance and diversity in a tallgrass prairie.

How grazing-induced ecosystem changes by ungulates indirectly affect other consumers is a question of great interest. I investigated the effect of grazing by American Bison (Bos bison L.) on an arthropod community in tallgrass prairie.

Positron-emission tomography imaging of the TSPO with [(18)F]FEPPA in a preclinical breast cancer model.

The present study aims to image the 18-kDa translocator protein (TSPO; formerly known as the peripheral benzodiazepine receptor) in a preclinical human breast cancer (BC) xenograft mouse model with positron-emission tomography (PET). An automated radiosynthesis of [(18)F]-N-(2-(2-fluoroethoxy)benzyl)-N-(4-phenoxypyridin-3-yl)acetamide ([(18)F]FEPPA) was validated for human use using a commercial synthesis module and resulted in a high radiochemical yield (30%±8%, uncorrected; n=54) and specific activity (6±4 Ci/μmol). Tumor uptake of [(18)F]FEPPA in mice bearing subcutaneous MDA-MB-231 BC xenografts was evaluated by PET-computed tomography imaging and ex vivo biodistribution studies.

Development of new carbon-11 labelled radiotracers for imaging GABAA- and GABAB-benzodiazepine receptors.

Two quinolines identified as positive allosteric modulators of γ-aminobutyric acid (GABA)(A) receptors containing the α(2) subunit, 9-amino-2-cyclobutyl-5-(6-methoxy-2-methylpyridin-3-yl)-2,3-dihydro-1H-pyrrolo[3,4-b]quinolin-1-one (4) and 9-amino-2-cyclobutyl-5-(2-methoxypyridin-3-yl)-2,3-dihydro-1H-pyrrolo[3,4-b]quinolin-1-one (5), were radiolabelled at the methoxy position with carbon-11 (half-life=20.4 min). These quinolines represent a new class of potential radiotracers for imaging the benzodiazepine site of GABA(A) receptors with positron emission tomography (PET).

Comparisons of [18F]-1-deoxy-1-fluoro-scyllo-inositol with [18F]-FDG for PET imaging of inflammation, breast and brain cancer xenografts in athymic mice.

Introduction: The aim of the study was to evaluate the uptake of [(18)F]-1-deoxy-1-fluoro-scyllo-inositol ([(18)F]-scyllo-inositol) in human breast cancer (BC) and glioma xenografts, as well as in inflammatory tissue, in immunocompromised mice. Studies of [(18)F]-2-fluoro-2-deoxy-d-glucose ([(18)F]-FDG) under the same conditions were also performed.

Methods: Radiosynthesis of [(18)F]-scyllo-inositol was automated using a commercial synthesis module.

Development of new radiopharmaceuticals for imaging monoamine oxidase B.

Introduction: Imaging monoamine oxidase B (MAO-B) in the central nervous system with PET is an important goal for psychiatric studies. We here report an improved and automated radiosynthesis of N-(6-[(18)F]-fluorohexyl)-N-methylpropargylamine ([(18)F]FHMP; [(18)F]-1), as well as the radiosynthesis of two new promising candidates for imaging cerebral MAO-B, namely, carbon-11-labeled 3-(4-[(11)C]-methoxyphenyl)-6-methyl-2H-1-benzopyran-2-one ([(11)C]-2) and N-((1H-pyrrol-2-yl)methyl)-N-[(11)C]-methyl-1-phenylmethanamine ([(11)C]-3).

Methods: Fluorine-18-labeled 1 was prepared via a tosyloxy precursor in 29%±5% uncorrected radiochemical yield, relative to [(18)F]-fluoride.

Xe3OF3(+), a precursor to a noble-gas nitrate; syntheses and structural characterizations of FXeONO2, XeF2·HNO3, and XeF2·N2O4.

Xenon fluoride nitrate has been synthesized by reaction of NO(2)F with [FXeOXeFXeF][AsF(6)] at -50 °C. It was characterized in SO(2)ClF and CH(3)CN solutions by low-temperature (14)N, (19)F, and (129)Xe NMR spectroscopy and in the solid state by low-temperature Raman spectroscopy (-160 °C) and single-crystal X-ray diffraction (-173 °C). The reactions were carried out using natural abundance and (18)O-enriched [FXeOXeFXeF][AsF(6)] and (15)NO(2)F to aid in the vibrational assignments of FXeONO(2) and to establish the likely reaction pathway.

NMR spectroscopic evidence for the intermediacy of XeF(3)(-) in XeF(2)/F(-) exchange, attempted syntheses and thermochemistry of XeF(3)(-) salts, and theoretical studies of the XeF(3)(-) anion.

The existence of the trifluoroxenate(II) anion, XeF(3)(-), had been postulated in a prior NMR study of the exchange between fluoride ion and XeF(2) in CH(3)CN solution. The enthalpy of activation for this exchange, ΔH(⧧), has now been determined by use of single selective inversion (19)F NMR spectroscopy to be 74.1 ± 5.

On the XeF+/H2O system: synthesis and characterization of the xenon(II) oxide fluoride cation, FXeOXeFXeF+.

The reported synthesis of the H(2)OF(+) cation as a product of the oxidative fluorination of H(2)O by [XeF][PnF(6)] (Pn = As, Sb) in HF solution has been reinvestigated. The system exhibits complex equilibria, producing two new Xe(II) compounds, [Xe(3)OF(3)][PnF(6)] and [H(3)O][PnF(6)] x 2 XeF(2), refuting the original claim for the synthesis of the H(2)OF(+) cation. Both compounds have been isolated and characterized by vibrational spectroscopy and single-crystal X-ray diffraction.

Uncoupling of the patterns of chromatin association of different transcription elongation factors by a histone H3 mutant in Saccharomyces cerevisiae.

The transcription elongation complexes yFACT, Spt4/Spt5, and Spt6/Iws1 were previously shown to follow similar patterns of association across transcribed genes in Saccharomyces cerevisiae. Using a histone H3 mutant, we now provide evidence that the mechanism of association of yFACT across genes is separable from that adopted by Spt4/Spt5 and Spt6/Iws1.

Synthesis and structural characterization of C(OTeF5)4 and a comparative structural study of the isoelectronic B(OTeF5)4- anion.

Tetrakis(pentafluoroorthotellurate)carbon(IV), C(OTeF5)4, was synthesized by reaction of CBr4 with BrOTeF5 in SO2ClF solution at -78 degrees C and was isolated as a colorless, crystalline solid that is room-temperature stable in SO2ClF and in the solid state. Both natural abundance and 99% 13C-enriched C(OTeF5)4 have been characterized in SO2ClF solution by 13C, 19F, and 125Te NMR spectroscopy. In contrast, C(OTeF5)4 undergoes rapid decomposition to O(TeF5)2 and CO2 in CH3CN at 10 degrees C but is stable at -40 degrees C.