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CreatorTitleDescriptionSubjectDate
151 Davidson, Diane W.Experimental manipulation of food bodies in CecropiaNeotropical Cecropia trees range from Mexico to Argentina and are typical of disturbed habitats. Cecropia plants provide food and housing for the ants in return for known or presumed protection from herbivores and vine cover. Glycogen-rich Mullerian bodies (MB's) are the predominant food source for ...Mullerian bodies; Trichilia; Cecropia tessmannii; Cecropia pungara1992
152 Olivera, Baldomero M.Conus peptides: phylogenetic range of biological activityThe major function of the venoms of the predatory marine snails belonging to the genus Conus is to paralyze prey. Thus, the venom of each Conus species acts on receptors and ion channels of the prey; previous studies suggested much less activity on homologous receptor targets in more distant taxa....Conus peptides; Conopeptides; Conotoxins1992
153 Olivera, Baldomero M.; Hillyard, David R.Heterodimeric structure of the spider toxin ω-Agatoxin IA revealed by precursor analysis and mass spectrometryWe report the first molecular characterization of a precursor sequence for a small, Ca2+ channel blocking, peptide spider toxin, ω-agatoxin IA. By integrating information generated from a molecular genetic approach using agatoxin cDNAs with data provided from mass spectrometry of the mature tox...Spider toxin w-Aga-IA; Heterodimeric structure1992
154 Beckerle, Mary C.Interaction between zyxin and α-actininZyxin is an 82-kD protein first identified as a component of adhesion plaques and the termini of stress fibers near where they associate with the cytoplasmic face of the adhesive membrane. We report here that zyxin interacts with the actin cross-linking protein α-actinin.Zyxin; Actinin; Actin1992
155 Ehleringer, James R.Plant adaptation in the Great Basin and Colorado PlateauAdaptive features of plants of the Great Basin are reviewed. The combination of cold winters and an arid to semiarid precipitation regime results in the distinguishing features of the vegetation in the Great Basin and Colorado Plateau. The primary effects of these climatic features arise from how t...Plant adaptation; Great Basin; Colorado Plateau; Cold deserts1992
156 Beckerle, Mary C.Purification and characterization of zyxin, an 82,000-Dalton component of adherens junctionsWe describe here the purification and characterization of a recently identified adherens junction protein that has an apparent molecular mass of 82 kDa on sodium dodecyl sulfate-polyacrylamide gels (Beckerle, M. C. (1986) J. Cell Biol. 103, 1679-1687). The 82-kDa protein was isolated from avian smoo...Zyxin1992
157 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
158 Adler, Frederick R.Aggregation and stability in parasite-host modelsThis paper generalizes the two-dimensional approximation of models of macroparasites on homogeneous populations developed by Anderson & May (1978), focusing on how the dispersion (the variance to mean ratio) of the equilibrium distribution of parasites on hosts is related to the stability of the equ...Aggregation; Stability; Host-parasite models1992-04
159 KSL News clip of Mario Capecchi receiving the National Medal of Science for 1991This 1 minute, 44 seconds news clip from Salt Lake City's KSLTV, Channel 5 shows Mario Capecchi receiving the National Medal of Science for 1991 from President George W. Bush at the June 13, 2002 awards ceremony. The medal was presented for Capecchi's work in genetics and his development of the pro...Transgenic mice; Gene targeting; Capecchi, Mario R.; Science - Awards - United States; Television broadcasting of news1992-06
160 Thomas, Kirk R.; Capecchi, Mario R.High-fidelity gene targeting in embryonic stem cells by using sequence replacement vectors.Mutations were targeted to the Hprt locus in murine embryonic stem cells by using sequence replacement vectors. When the vector was designed such that the mutated sequences were flanked on both sides by several kilobases of DNA homologous to the target locus, replacement of chromosomal sequences wit...Drug Resistance; Gene Rearrangement; Gentamicins1992-07
161 Capecchi, Mario R.Reexamination of gene targeting frequency as a function of the extent of homology between the targeting vector and the target locus.Mutations were targeted to the Hprt locus of mouse embryo-derived stem cells by using 22 different sequence replacement and sequence insertion vectors. The targeting frequency was examined at two sites within the Hprt locus as a function of the extent of homology between the targeting vector and the...Cell Line; DNA Transposable Elements; Embryo; Exons; Mice1992-08-12
162 Sperry, John S.Winter xylem embolism and spring recovery in Betula cordifolia, Fagus grandifolia, Abies balsamea, and Picea rubensXylem embolism was monitored from mid-winter to mid-summer in four co-occurring species: Betula cordifolia (Reg.) Fern., Fagus grandifolia Ehrh., Abies balsamea (L.) Mill., Picea rubens Sarg. The study site was a west-facing slope in the northern Green Mountains of Vermont, U.S.A.; Betula and conife...Conductivity; Hydraulic; Trees1993
163 Bohs, Lynn A.Cyphomandra (Solanaceae)Cyphomandra betacea (Cavanilles) Sendtner Syn. Cyphomandra crassifotia (Ortega) Kuntze, Solanum betacea Cavanilles, Solanwn crassifolium Ortega. Ref. FB 13(5B/1) 1962: 12; Bohs, 1986: 170. Cultivated tree. Andean II. 1000-3000 m. Voucher: Nunez et al. 8257 (MO!) Depts.: AM, CU, HU, SMCyphomandra; Solanum1993
164 Coley, Phyllis D.; Kursar, Thomas A.Colonization of tropical rain forest leaves by epiphylls: effects of site and host plant leaf lifetimeIn humid tropical regions, leaves are frequently colonized by epiphylls (Richards 1954, Pocs 1978, 1982). Lichens and liverworts usually dominate, although mosses, algae, and cyanobacteria can also occur (Winkler 1971, Smith 1982). The interactions between epiphylls and host leaves have not been wel...Tropical forest; Epiphylls; Panama; Hybanthus prunifolius; Light interception1993
165 Davidson, Diane W.Ant-plant symbioses in Africa and the neotropics : history, biogeography and diversitySymbiotic ant-plant relationships afford an excellent opportunity to analyze the effects of both historical and ecological factors on the evolution of mutualisms. Occurring in tropical forests throughout the world, all myrmecophytic plants provide food and permanent housing to ants; the ants, in t...Ant-plant symbiosis; Africa; Neotropics; Myrmecophytes; Plant-ants1993
166 Clayton, Dale H.Common grackle anting with lime fruit and its effect on ectoparasitesAnting is stereotyped behavior in which birds ex- pose themselves to fluid-secreting ants or other pun- gent substances. During "active" anting a bird crush- es an ant in the bill and rubs it frenetically through its plumage (Rothschild and Clay 1952). During "passive" anting a bird entices ants to ...Quiscalus quiscala; Columbicola columbae; Anting; Ectoparasites1993
167 Olivera, Baldomero M.; ; McIntosh, J. MichaelLocalization of [125I] ω-conotoxin GVIA binding in human hippocampus and cerebellumTHE peptide toxin ω-conotoxin GVIA (ω-CgTx) has been shown to be a high affinity ligand for N-type calcium channels in the brain. We have employed [125I]ω-CgTx to localize N-type channels in human hippocampus and cerebellum using autoradiography. Ten micron thick slidemounted tissue sections of...Conotoxins; Peptide toxins1993
168 Bastiani, MichaelCell-cell interactions during the migration of an identified commissural growth cone in the embryonic grasshopperOne of the fascicles of the posterior commissure of the embryonic grasshopper is pioneered by an individually identifiable neuron named Q1. Q1 initially grows along a longitudinal pathway established by another pioneer neuron, MPl, and then crosses to the midline, where it meets and fasciculates wi...Commissure; Pathfinding; Filopodia1993
169 Beckerle, Mary C.Evidence for the selective association of a subpopulation of GPIIb-IIIa with the actin cytoskeletons of thrombin-activated plateletsActivation of blood platelets triggers a series of responses leading to the formation and retraction of blood clots. Among these responses is the establishment of integrin-mediated transmembrane connections between extracellular matrix components and the actin cytoskeleton of the platelet.Actin; GPIIb-IIIa1993
170 Adler, Frederick R.Migration alone can produce persistence of host-parasitoid modelsIt has long been recognized that the unstable equilibrium of a single-patch predator-prey model cannot be stabilized by diffusive coupling with identical patches, since the coupled system acts exactly like the single-patch system if the patches are synchronized (Maynard Smith 1974; Allen 1975; Reeve...Heterogeneity; Nicholson-Bailey; migration rates1993
171 Ehleringer, James R.Seedling size and survival for Chrysothamnus nauseosusSeedling size and survival in relation to summer drought were examined for Chrysothamnus nauseosus growing under field and greenhouse conditions. In the field, summer survival rates were less than 2% annually for the three years monitored. The effect of initial seedling height on subsequent survival...Chrysothamnus nauseosus; Seedling size; Seedling survival1993
172 Bastiani, MichaelGrowth cone dynamics during the migration of an identified commissural growth coneWe have used time-lapse video microscopy to study the behavior of a neuron, 01, that pioneers the posterior commissure of the embryonic grasshopper. Our goal is to use time-lapse video as a tool to acquire a precise picture of normal development over time, and thereby identify stereotypic activities...Time-lapse video; Commissure; Grasshopper; Pathfinding; Filopodia; Confocal microscopy; Adhesion1993
173 Davidson, Diane W.Evolutionary ecology of symbiotic ant-plant relationshipsAbstract.--A tabular survey of ant-plant symbioses worldwide summarizes aspects of the evolutionary ecology of these associations. Remarkable similarities between ant-plant symbioses in disjunct tropical regions result from convergent and parallel evolution of similarly preadapted ants and plants. ...Symbioses; Evolution; Taxonomic1993
174 Olivera, Baldomero M.; McIntosh, J. MichaelConus peptides as tools for the neuroscientistRecombinant DNA technology has had a powerful impact on understanding receptors and ion channels, the key components in the nervous system that are involved in intercellular communication. Cloning genes encoding these proteins has revealed that for every receptor and ion channel type, multiple molec...Conus peptides; Conotoxins1993
175 Thomas, Kirk R.; Capecchi, Mario R.Location of crossovers during gene targeting with insertion and replacement vectors.Gene targeting was used to introduce nonselectable genetic changes into chromosomal loci in mouse embryo-derived stem cells. The nonselectable markers were linked to a selectable marker in both insertion- and replacement-type vectors, and the transfer of the two elements to the Hprt locus was assaye...Genetic Vectors; Molecular Sequence Data; Restriction Mapping1993-04
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