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CreatorTitleDescriptionSubjectDate
1 Sokolsky, Pierre; Cassiday, George L.Evidence for a high-energy cosmic-ray spectrum cutoffWe report a measurement of the ultrahigh-energy cosmic-ray spectrum using an atmospheric fluorescence technique for extensive-air-shower detection. The differential spectrum between 0.1 and 10 EeV (1 EeV = 10^18 eV) is well fitted by a power law with slope 2.94 ±0.02. Above 10 EeV evidence is prese...Energy spectrum; Extensive air showers; Spectral cutoff1985-04
2 Coley, Phyllis D.Coibanoles, a new class of meroterpeniods produced by pycnoporus sanguineusThree new terpenoids of mixed biosynthetic origin were isolated from the culture filtrate of the endophytic fungus Pycnoporus sanguineus. Their structures were determined by extensive spectroscopic analyses. We have named these tricyclic and tetracyclic metabolites ?coibanoles A?C? in reference to...2012
3 Williams, Clayton C.Direct imaging of SiO2 thickness variation on Si using modified atomic force microscopeFabrication techniques of metal-oxide-semiconductor ~(MOS) transistors have been improved very rapidly during the last several decades. With this trend, scaling down of MOS transistors is necessary to improve the speed of circuits and the packing density of discrete devices. Both lateral and vertic...Silicon dioxide; Oxide layer; Phosphorus ions; Oxide capacitance; Dopant profile1996-03-01
4 Davidson, Diane W.; Rickart, Eric Allan; Keiter, Robert B.Selecting wilderness areas to conserve Utah's biological diversityCongress is currently evaluating the wilderness status of Bureau of Land Management (BLM) public lands in Utah. Wilderness areas play many important roles, and one critical role is the conservation of biological diversity.Bureau of Land Management; Conservation; Endemic species; Exotic species; Cryptobiotic soils; Plants; Bees; Vertebrates1996
5 Davidson, Diane W.Nonnative brome grasses in the new national monumentIncluded within the boundaries of the Grand-Staircase Escalante National Monument are a number of noxious weeds for which the BLM mandates control. In addition to listed weeds are nonnative brome grasses [Bromus tectorum and Bromus rubens), which can potentially convert native ecosystems to biologic...Noxious weeds, Cheatgrass,1998
6 Davidson, Diane W.Dispersal adaptations of some acacia species in the Australian arid zoneMost Australian representatives of the genus Acacia have diaspores with arillate appendages indicative of adaptation for active dispersal by animals. Based on physical and chemical characteristics of these arils and mechanisms of diaspore presentation, a number of arid zone acacias can be distingu...Acacia; Australian arid zone; Dispersal ecology; Fruit quality; Myrmecochory; Ornithochory; Seed parasitoids; Soil nutrients1984
7 Adler, Frederick R.Deconvolution of isotope signals from bundles of multiple hairsSegmental analysis of hair has been used in diverse fields ranging from forensics to ecology to measure the concentration of substances such as drugs and isotopes. Multiple hairs are typically combined into a bundle for segmental analysis to obtain a high-resolution series of measurements. Individua...2014-01-01
8 Stang, Peter J.Self-selected formation of single discrete supramolecules with flexible, bidentate ligands in the coordination-driven self-assemblyFlexible donor ligands like 1,2-bis(3-pyridyl)ethyne or 1,4-bis(3-pyridyl)-1,3-butadiyne selfassemble into discrete 2-D supramolecules instead of infinite networks upon combination with organoplatinum 90, 120, and 180 degree acceptor units. These systems are unique examples of versatile pyridine...Bidentate ligands; Flexible donor ligands; Supramolecules; Coordination-driven self-assembly2008
9 Ehleringer, James R.Interspecific competition and resource pulse utilization in a cold desert communityIn desert ecosystems a large proportion of water and nitrogen is supplied in rain-induced pulses. It has been suggested that competitive interactions among desert plants would be most intense during these pulse periods of high resource availability. We tested this hypothesis with three cold desert s...Atriplex confertifolia; Chrysothamnus nauseosus; Colorado Plateau; desert; Gutierrezia sarothrae; Neighbor removal; Plant competition; Resource pulses; Pulse utilization; Stable isotopes; Water uptake2002
10 Williams, Clayton C.Mapping of mobile charges on insulator surfaces with the electrostatic force microscopeMigration of surface ions in lateral fields on insulator surfaces may modify the electrical characteristics of underlying semiconductor structures causing device instabilities. A high sensitivity electrostatic force microscope is used to image the movement and spatial distribution of surface ions on...Insulator surfaces; Surface ions; Electrostatic force microscope1993
11 Potts, Wayne K.Relationship of virulence factor expression to evolved virulence in mouse-passaged Cryptococcus neoformans linesSerial passage of Cryptococcus neoformans in mice increases virulence relative to the nonpassaged line. Postpassaged lines showed no difference in the expression of most known virulence factors, with the exception that the more virulent lines had smaller capsules in vitro. These data imply that othe...Capsule; Death; Passage2005
12 Olivera, Baldomero M.; McIntosh, J. MichaelSolution structure of αA-conotoxin EIVA, a potent neuromuscular nicotinic acetylcholine receptor antagonist from Conus ermineusWe report the solution three-dimensional structure of an αA-conotoxin EIVA determined by nuclear magnetic resonance spectroscopy and restrained molecular dynamics. The αA-conotoxin EIVA consists of 30 amino acids representing the largest peptide among the α/αAfamily conotoxins discovered so f...Conotoxins; A-conotoxin EIVA; Conus ermineus2003
13 Mishchenko, Eugene; Raikh, Mikhail E.Electrostatics of straight and bent single-walled carbon nanotubesResponse of a single-walled carbon nanotube to external electric field, F, is calculated analytically within the classical electrostatics. Field-induced charge density distribution is approximately linear along the axis of a metallic nanotube and depends rather weakly, as ln(h/ r), on the nanotube...Electrostatics2006-10
14 Wu, Yong-ShiTransitions between the quantum Hall states and insulators induced by periodic potentialsTransitions between two quantum Hall states or between a quantum Hall state and a Mott insulator induced by periodic potentials are studied in the 1 /TV expansion. The transitions are found to be continuous in the large-TV limit and are described by a critical point that depends on a real parameter ...Periodic potentials; Insulators1993-03
15 Davidson, Diane W.Microtopography of microbiotic crusts on the Colorado Plateau, and distribution of component organismsWe analyzed the microtopography of microbiotic soil crusts at 3 sites on the Colorado Plateau of southern Utah and investigated distributions of cyanobacteria and several lichens in distinctive microhabitats created by this topography. At all 3 sites the long axes of linear soil mounds were oriented...Microtopography; Microbiotic crusts; Colorado Plateau; Cryptobiotic soil; Colonization; Nonrandom orientation; Exposure; Collema; Disturbance history; Microhabitat2000
16 Ehleringer, James R.; Negus, Norman C.Red Butte Canyon Research Natural Area: history, flora, geology, climate, and ecologyRed Butte Canyon is a protected, near pristine canyon entering Salt Lake Valley, Utah. It contains a well-developed riparian zone and a perennial stream; hillside vegetation ranges from grasslands on the lower limits to Douglas-fir and aspen stands at the upper elevations. In this paper we describe ...Intermountain West; Grassland; Oak-maple; Plant adaptation; Red Butte Canyon Research Natural Area; Human impact1992
17 Shapiro, Michael D.Turnover of sex chromosomes in the stickleback fishes (Gastrosteidae)Diverse sex-chromosome systems are found in vertebrates, particularly in teleost fishes, where different systems can be found in closely related species. Several mechanisms have been proposed for the rapid turnover of sex chromosomes, including the transposition of an existing sex-determination gen...Sex determination; Gasterosteus aculeatus; Gasterosteus wheatlandi; Pungitius pungitius; Culaea inconstans; Apeltes quadracus; Gasterosteidae2009-02-20
18 Ehleringer, James R.; Belnap, JayneSensitivity of the Colorado plateau to change: climate, ecosystems, and societyThe Colorado Plateau is located in the interior, dry end of two moisture trajectories coming from opposite directions, which have made this region a target for unusual climate fluctuations. A multidecadal drought event some 850 years ago may have eliminated maize cultivation by the first human settl...Colorado Plateau; Biological crust; Climate change; Megadrought; Ranching; Dry crop productivity; Extractive industries; Pueblo Indians; Fremont culture2008
19 Ehleringer, James R.Carbon isotope discrimination and water relations of oak hybrid populations in southwestern UtahThe evergreen oak Quercus turbinella and the deciduous Q. gambelii form natural hybrids in southwestern Utah and northern Arizona. Hybrid individuals also are found in northern Utah in a region where only Q. gambelii currently exists, indicating that Q. turbinella has recently retreated southward. ...Quercus turbinella; Oak hybrids; Leaf structure; Leaf nitrogen; Carbon isotope discrimination; Water potential; Oak ecology2000
20 Miller, Joel StevenCollinear ferromagnetism and spin orientation in the molecule-based magnets M[N(CN)2]2 (M=Co,Ni)Zero-field unpolarized neutron powder diffraction has been used to study the low-T magnetic structure and T-dependent crystal structure of M[N(CN)2]2 (M=Co,Ni). Both compounds show collinear ferromagnetism with spin orientation along the c axis. The results provide the determination of a complete ma...Magnetic; Diffraction; Structure1999
21 Olivera, Baldomero M.; McIntosh, J. MichaelNuclear magnetic resonance solution conformation of α-conotoxin AuIB, an α3ß4 subtype-selective neuronal nicotinic acetylcholine receptor antagonistThe neuronal nicotinic acetylcholine receptors constitute a highly diverse group, with subtypes consisting of pentameric combinations of α and ß subunits. α-Conotoxins are a homologous series of small peptides that antagonize these receptors. We present the three-dimensional solution structure ...Conotoxins; a-conotoxin AuIB2000
22 Ehleringer, James R.; Rickart, Eric Allan; Dearing, Maria-DeniseStable isotope ratios (?15N AND ?13C) of syntopic shrews (SOREX)Local species richness in shrew (Soricidae) assemblages is often high, and the mechanisms of ecological separation remain relatively unexplored. In this study, hair samples from 6 species of Sorex in 3 separate assemblages were analyzed for stable carbon (13C/12C) and nitrogen (15N/14N) isotope rati...2004
23 Miller, Joel StevenOptical control of magnetization in a room-temperature magnet: V-Cr Prussian blue analogWe report reversible photoinduced magnetic phenomena for a V-Cr Prussian blue analog (Tc~350 K). This molecule-based magnet exhibits a decrease in magnetization upon illumination with UV light (λ~350 nm) and reaches a metastable state that has a long lifetime at low temperatures (>106 s at 10 K). ...2010-09
24 Coley, Phyllis D.; Kursar, Thomas A.Using ecological criteria to design plant collection strategies for drug discoveryTropical forests are one of the most diverse and endangered habitats on earth. They have also been portrayed as a source of future pharmaceuticals, yet finding useful compounds can be both scientifically and politically challenging. Increasingly, over the past decade, the potential value of medicina...Drug discovery; Biodiversity2003
25 Sekercioglu, CaganThe need to quantify ecosystem services provided by birdsWhat are birds worth-what is their actual dollar value to human society? To most of us in the ornithological community, birds are invaluable. But in these times we need more specific rationales to convince policy makers and business leaders to include bird conservation in land-use and development de...2011-01-01
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