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1.
Vertical polyacrylamide gel electrophoresis was used to separate enzyme proteins at 73 putative loci in natural house fly
populations sampled in central Iowa. Thirty-nine of the loci were polymorphic (53%). The mean effective number of alleles
per polymorphic locus was 1.93 and 1.47 alleles among 68 scored loci. Observed and expected heterozygosities at 34 house fly
loci were 0.1628 and 0.1834, respectively. No statistically significant differentiation was detected among nine central Iowa
fly populations in 1989 or among nine Iowa and three Minnesota populations in 1990.
Journal Paper No. J-14125 of the Iowa Agriculture and Home Economics Experiment Station, Ames. Project No. 2949. 相似文献
2.
Earl P. Wixom 《Arts Education Policy Review》2013,114(4):37-39
Abstract Shoshana Zuboff. In the Age of the Smart Machine: The Future of Work and Power. New York: Basic Books, 1988, 468 pp. $11.95 paperback. George Gilder. Microcosm: The Quantum Revolution in Economics and Technology. New York: Simon &; Schuster, 1989. 426 pp. $19.95 hardcover. Loren Baritz. The Good Life. New York: Alfred A. Knopf, Inc., 1988. 361 pp. $19.95 hardcover. Miles Orville. The Real Thing: Imitation and Authority in American Culture, 1880–1940. Chapel Hill: University of North Carolina Press, 1989. 382 pp. $14.95 paperback. Peter Shaw. The War Against the Intellect. Iowa City: The University of Iowa Press, 1989. 181 pp. $10.95 paperback. Robert Alter. The Pleasures of Reading in an Ideological Age. New York: Simon &; Schuster, 1989. 250 pp. $18.95 hardcover. Ian Crofton. A Dictionary of Art Quotations. New York: Macmillan Publishing Company, 1989. $19.95 hardcover. 相似文献
3.
Extensive land-use changes in Iowa have increased erosional processes and the amount of fines deposited on stream beds. Large amounts of fines cover the other bed substrate that are essential habitat for invertebrates and fish. In Iowa and other agricultural Midwestern states, riparian conservation land-uses are being established to minimize sediment inputs to streams. This study compared stream bed substrate composition in reaches adjacent to: riparian forest buffers, grass filters, row-cropped fields, pastures with cattle fenced out of the stream and continuous, rotational and intensively grazed rotational pastures, in three regions of Iowa. The objective was to examine the impacts of the adjacent riparian land-uses on stream bed substrate composition. The percentages of fines in this study ranged from: 36 to 63% in the central region; 10 to 31% in the northeast region; and 22 to 85% in the southeast region. The high percentage of fines in most stream bed reaches indicates high embeddedness. The high embeddedness resulted in the few significant differences in substrate percentages among riparian land-uses. Decades of agricultural land-uses have heavily impacted stream beds and only significant reductions in surface and bank erosion at the watershed scale can begin to reverse this trend. There were indications that riparian forest buffers and to a lesser degree, pastures with cattle fenced out of the stream, could decrease fines resulting in a more diverse substrate composition. Overall, more targeted approaches for the establishment of conservation land-uses in combination with other restoration practices (e.g. in-stream enhancements) are required to successfully decrease fines on stream beds. 相似文献
4.
Moreira BG You Y Behlke MA Owczarzy R 《Biochemical and biophysical research communications》2005,327(2):473-484
Single and dual-labeled fluorescent oligodeoxynucleotides are used in many molecular biology applications. We investigated the effects of commonly used fluorescent dyes and quenchers on the thermodynamic stability of a model probe-target DNA duplex. We demonstrate that those effects can be significant. Fluorescent dyes and quenchers were attached to the probe ends. In certain combinations, these groups stabilized the duplex up to 1.8kcal/mol and increased T(m) up to 4.3 degrees C. None of the groups tested significantly destabilized the duplex. Rank order of potency was, starting with the most stabilizing group: Iowa Black RQ approximately Black Hole 2>Cy5 approximately Cy3>Black Hole 1>QSY7 approximately Iowa Black FQ>Texas Red approximately TAMRA>FAM approximately HEX approximately Dabcyl>TET. Longer linkers decreased stabilizing effects. Hybridizations to targets with various dangling ends were also studied and were found to have only minor effects on thermodynamic stability. Depending on the dye/quencher combination employed, it can be important to include thermodynamic contributions from fluorophore and quencher when designing oligonucleotide probe assays. 相似文献
5.
Ettinger RL 《Gerodontology》2012,29(2):e1252-e1260
doi: 10.1111/j.1741‐2358.2011.00471.x A 30‐year review of a geriatric dentistry teaching programme Objective: To review the development of the Geriatric Dental and Special Needs Education programme at the University of Iowa over the last 30 years. Background: The programme at Iowa evolved from a didactic elective programme taught by a single faculty person to a required didactic and clinical programme, which includes a Special Care Clinic in the dental school and a mobile unit with portable dental equipment which serves ten area nursing homes with comprehensive care. Materials and methods: Changes have been made in the programme over time based on formal and informal feedback from students and graduates, and we have also looked at the impact of the programme on dental services to our target population. Results: The factors influencing the curriculum development are identified and discussed. Conclusion: As no dental schools are the same, some general applications are suggested from the Iowa experience. 相似文献
6.
Milton A. Rogers Helen L. Gál Harry T. Horner Jr. 《In vitro cellular & developmental biology. Plant》1974,9(6):463-467
Summary The primary goal of this study was to establish callus cultures of selected plant taxa containing both normal (N) and cytoplasmic
male-sterile (CMS) lines. A secondary goal was to attempt to differentiate the calli into whole flowering plants. Undifferentiated
and organ differentiated calli were produced in specific lines of N and CMS sorghum, pepper, sunflower, and tobacco. Calli
from both N and CMS lines of a given species developed similarly and grew well. Even though whole flowering plants have not
yet been produced from any of the lines, this approach allows for good production of callus for studies dealing with CMS.
Journal Paper No. J-7741 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 1914. 相似文献
7.
Marie Bourguignon Kenneth J. Moore Robert C. Brown Kwang Ho Kim Brian S. Baldwin Roger Hintz 《Bioenergy Research》2017,10(1):36-49
Kenaf (Hibiscus cannabinus L.) has potential as an annual herbaceous biomass feedstock. It is not typically grown in the American Midwest; however, kenaf may be attractive as an alternative crop for Iowa and the Corn Belt. In this study, seven kenaf varieties were grown in Iowa and evaluated for their productivity. More specifically, our research questions were the following: (1) how do kenaf varieties perform in Iowa for yield? (2) How does fiber morphology and quality differ among varieties and among core and bast fiber? And (3) What potential does kenaf (bast and core) have for producing fuel using fast pyrolysis? Tainung 2, one of the varieties, reached the best yield in Central Iowa over multiple years. Bast kenaf contained 8 % more cellulose and 23 % less hemicellulose than the core but it varied among varieties. Also, regardless of variety, core was composed of 40 % more lignin than bast. Core was found to have higher potential for fast pyrolysis than the bast but its potential was variety-dependent. Overall, kenaf could be grown to diversify Iowa agriculture and provide alternative feedstock to the biofuel industry. 相似文献
8.
Zhang S Liu G Liu X Yin D Dou S He J Rusckowski M Hnatowich DJ 《Bioconjugate chemistry》2007,18(4):1170-1175
A useful property of optical imaging is the potential to modulate the detectable signal to improve target/nontarget ratios. When administered as a dimer of a fluorophore- and a quencher-conjugated duplex arranged to inhibit fluorescence but designed to dissociate only in the presence of its target, the fluorescence signal should in principle appear only in the target. This laboratory has demonstrated the feasibility of this approach by using a duplex consisting of a linear oligomer conjugated with Cy5.5 (emitter) hybridized to another linear oligomer conjugated with Iowa Black (quencher) in a pretargeting optical study. Now eight duplexes consisting of combinations of 18 mer linear phosphodiester (PO) and phosphorothioate (PS) DNAs and phosphorodiamidate morpholinos (MORFs) conjugated with Cy5.5 (emitter) and Iowa Black (quencher) were variously screened for in vitro duplex stability. The MORF/PO duplex was selected for further study based on evidence of stability in 37 degrees C serum. Simultaneously, the kinetics of quenching were investigated in vitro and in vivo in mice. Thereafter, mice were implanted in one thigh with MORF/PO Cy 5.5 microspheres and the complementary PS Iowa Black administered iv to measure the extent and kinetics of duplex formation in the target. While all duplexes were stable in buffer, only the MORF/PO duplexes and possibly all PS containing duplexes were stable in 37 degrees C serum for at least 4 h. The kinetics of quenching were found to be rapid in vitro, with a 80-90% decrease in Cy5.5 fluorescence immediately following formation of a PS/PS homoduplex, and in vivo, with a 27 to 38% decrease in target thigh/nontarget ratio within 1 h following administration of the complementary PS Iowa Black complementary DNA but not the random control DNA to mice implanted with MORF/PO Cy5.5 microspheres. This investigation has provided additional evidence that Cy5.5 may be efficiently and rapidly quenched by Iowa Black when both are conjugated to complementary oligomers and that the resulting inhibition of fluorescence is sufficiently persistent for imaging. 相似文献
9.
S. Scott Whitmore Selena Losee Laurel Meyer Theresa A. Spradling 《Conservation Genetics》2013,14(4):771-781
In light of global declines in amphibian populations, genetic data have become increasingly important for understanding population structure and for revealing hidden diversity. At the species level, Notophthalmus viridescens is an IUCN species of “least concern”, but the subspecies N. v. louisianensis (central newt) is listed as “threatened” in Iowa, a state on the western periphery of the species range. Genetic data were collected from 282 N. v. louisianensis from 14 sites in Iowa. Sequences from 1,054 nucleotides of mitochondrial DNA from Iowa newts revealed unexpected diversity in the form of two major haplotype groups that are not sister clades, with southern Iowa N. v. louisianensis being more closely related to N. v. piaropicola (peninsula newt) from Florida than to consubspecifics in Iowa. Sequence differentiation indicates that the two lineages of newts present in Iowa diverged near the beginning of the Pleistocene. Northern and southern Iowa haplotypes were found together at one site, indicating an opportunity for hybridization near Remington’s biogeographic suture zone 1, a hotspot for hybridization in other species. Three microsatellite loci provided additional evidence for distinctness of northern and southern Iowa newt populations. This study highlights the relevance of historical biogeography to conservation, as management strategies for N. v. louisianensis in Iowa must reflect previously unrecognized diversity in this species. Nuclear and mitochondrial data indicate genetic isolation of nearby populations on the same drainage, and field data suggest the decline of one study population, emphasizing the need for identification and protection of newt breeding sites in Iowa. 相似文献
10.
Concentrations of polychlorinated biphenyls (PCBs) in common carp, Cyprinus carpio, from the Des Moines River, Iowa, were assessed for variability related to sampling location, sampling period, fish age, and fat content. Concentrations were highest at a location near the City of Des Moines; they were substantially lower in 1981 than in 1980. Age and fat content had little influence on PCB concentrations in carp. Overall concentrations were some of the lowest recorded in the United States and Canada in recent times.The Unit is jointly supported by Iowa State University, the Iowa State Conservation Commission, and the U.S. Fish and Wildlife Service.Journal Paper No. 10754 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 2465. Financed by a grant from the U.S. Department of Defense Army Corps of Engineers and made available through the Engineering Research Institute, Iowa State University. 相似文献
11.
Small chromosome aberrations were utilized to construct compound bands in the 3C region of Drosophila melanogaster salivary gland chromosomes. The results imply that one should expect to find multiple functions associated with single bands, especially heavy bands. It is suggested that the natural occurrence of compound bands needs to be recognized and that exceptions to the one gene: one band correspondence are expected to occur.Journal Paper No. J-9459 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa, Project No. 1985 相似文献
12.
Hugh Dingle Kenneth E. Evans James O. Palmer 《Evolution; international journal of organic evolution》1988,42(1):79-92
Genetic parameters were assessed in the nonmigratory Puerto Rico population of the milkweed bug, Oncopeltus fasciatus, and compared with parameters estimated in a migratory population from Iowa (Palmer and Dingle, 1986). Offspring-parent regression analysis provided initial estimates of heritabilities and phenotypic and genetic correlations among wing length, head-capsule width, female age at first reproduction, fecundity for the first and second five days of reproduction by females, and clutch size for the first and second five days of reproduction by females. Replicated bidirectional selection for wing length was then imposed, with a direct response to selection revealing substantial additive genetic variance for this trait, as was also the case with the Iowa population. Assays for correlated response to selection yielded two further similarities to Iowa: a positive response in head-capsule width and no consistent response in age at first reproduction. In contrast to the results with Iowa bugs, neither regression analysis nor selection revealed statistically significant genetic correlations between fecundity measures and those of other traits. In both populations the potential exists for body-size characters to evolve together independently of age at first reproduction; but in the nonmigratory Puerto Rico bugs, fecundity does not contribute to a life-history syndrome involving genetic correlations among these traits. 相似文献
13.
Protists constitute the bulk of eukaryotic diversity yet their genomes remain relatively unexplored. To address this issue, a workshop entitled, "Frontiers in Genomics: Insights into Protist Evolutionary Biology", was convened at the University of Iowa on June 19-21, 2004. The specific aims of the workshop were to define the role of genomics in the eukaryotic tree of life, to identify challenges in characterizing protist (i.e. microbial eukaryote) genomes, and in proposing specific solutions to these challenges. The findings of the workshop are presented here and in a white paper that provide a set of guidelines for organizing the protist community and for planning and executing a protist genome project. 相似文献
14.
Constantine J. Alexopoulos 《American journal of botany》1959,46(2):140-142
Alexopoulos , Constantine J. (State U. Iowa, Iowa City.) The laboratory cultivation of Stemonitis. Amer. Jour. Bot. 46(2): 140-142. Illus. 1959.—The cultivation of a species of Stemonitis, probably S. flavogenita, in laboratory culture is reported here for the first time. The organism completed its entire life cycle on artificial media from spore to spore, in the presence of contaminating bacteria, in 36 days. The plasmodium, characteristically different from those of the Physarales, is described and illustrated. 相似文献
15.
Reehan S. Mirza Sheri A. Fisher Douglas P. Chivers 《Environmental Biology of Fishes》2003,66(4):321-327
In two laboratory experiments we tested juvenile yellow perch, Perca flavescens, for behavioural responses to alarm cues of injured conspecifics and several prey guild members: adult perch, Iowa darters, Etheostoma exile and spottail shiners, Notropis hudsonius. Spottail shiners are phylogenetically distant to yellow perch whereas Iowa darters and perch are both members of the Family Percidae. Groups of juvenile yellow perch increased shoal cohesion and movement towards the substrate after detecting conspecific alarm cues when compared to cues of injured swordtails, Xiphophorus helleri, a species phylogenetically distant from perch. Individual juvenile perch increased shelter use and froze more when exposed to chemical alarm cues from both juvenile and adult perch, shiners and darters compared to exposure to injured swordtail cues or distilled water. The response to cues of darters may indicate that alarm cues are evolutionarily conserved within percid fishes or that perch had learned to recognize darter cues. The response to spot tail shiners likely represents learned recognition of the cues of a prey guild member. 相似文献
16.
Etan Markowitz 《Biochemical genetics》1970,4(5):595-601
Three models of codon fixation variability are formulated. The first assumes that all codons have the same fixation rate. The second assumes that some codons are invariant and that all variable codons have the same fixation rate. The third assumes that some codons are invariant and that the variable codons comprise two classes, all members of each class having the same fixation rate. Maximum likelihood estimates of the parameters and tests of goodness-of-fit are given for each model.Paper number 1383 from the Laboratory of Genetics. Work performed in part at the University of Iowa, Department of Preventive Medicine and Environmental Health and Department of Statistics, Iowa City, Iowa. Computing supported by the Graduate College, University of Iowa. 相似文献
17.
Theresa A. Spradling Jeffrey W. Tamplin Samantha S. Dow K. J. Meyer 《Conservation Genetics》2010,11(5):1667-1677
The North American wood turtle, Glyptemys insculpta, is a semi-aquatic species that is considered rare, threatened, or endangered over much of its range. In this study, a particularly
vulnerable peripheral isolate population in Iowa has been monitored over a period of 7 years. Population census size, estimated
from mark-recapture data, and age structure determined from morphology are compared with genetic variation assessed using
microsatellites. For reference, the genetics and demographics of this peripheral isolate are compared to data from a more
dense population nearer the core of the species range in West Virginia. Geneflow between the Iowa population and a nearby
population in Minnesota also is assessed. Genetic data indicate that the Iowa population is isolated, unique, and diverse.
Although the Iowa population has lower allelic richness, lower heterozygosity, and smaller genetic effective population size
than does the West Virginia population, the difference is not dramatic despite its lower population size, position at the
periphery of the species range, and biogeographic history. The Iowa population is not inbred, and there is no genetic signature
of a recent population bottleneck. However, interpretations of recent population dynamics based on genetic data may be unduly
encouraging in long-lived species such as G. insculpta. Field data suggest a nearly complete lack of recruitment in Iowa. A number of environmental and anthropogenic factors, including
recent increases in summer flooding during egg incubation, may have a more negative impact on the Iowa population than on
the West Virginia population. 相似文献
18.
《Plains anthropologist》2013,58(81):183-219
AbstractDue to strong Indian opposition and ambiguous state laws, Iowa archaeologists have found it impossible to investigate aboriginal cemetery areas in recent years. The accidental discovery of an Archaic ossuary at a construction site on the grounds of the Lewis Central School in southwestern Iowa provided a turning point in Indian-archaeologist relations which ultimately led to a resolution of the problem through the enactment of new sections in the Iowa legal code. This article traces the history of events leading up to the discovery of the Lewis Central School site (13PW5), and provides substantive data concerning materials recovered from that site. This is done to demonstrate that a considerable amount of information is obtainable through such studies and to provide archaeologists and physical anthropologists with a frame of reference to evaluate the results obtained. The paper concludes with a presentation of additions and changes in the Iowa legal code and a discussior, of the effects the Iowa precedent may have on anthropologists, Indians, and state officials elsewhere. 相似文献
19.
Nectria atrofusca, a parasite ofStaphylea trifolia in eastern North America but extending as far west as Iowa, is redescribed. Its anamorph is described asFusarium staphyleae Samuels & Rogerson, sp. nov. 相似文献
20.
Thomas G. Lammers 《Brittonia》2017,69(3):253-264
Thirty-eight plant names were explicitly ascribed to Iowa in Alphonso Wood’s Class-book of Botany. Fourteen represented the first report from the state for their species, while eight reports were likely erroneous. In the preface, Wood acknowledged “Dr. Cousens,” not otherwise identified, as the source of his specimens from Iowa. Circumstantial evidence suggests that this was Moses Cousins Jr., born in Vermont in 1827, who practiced medicine at Albia in Monroe County, Iowa, from 1850 until his death in 1868. 相似文献