Center for Teaching Excellence Scholarly Works

Permanent URI for this collection

This collection contains publications by faculty affiliated with the Center for Teaching Excellence.

Browse

Recent Submissions

  • Publication
    Restriction Endonuclease Cleavage Site and Length Polymorphisms in Mitochondrial DNA of Apis mellifera mellifera and A. m. carnica (Hymenoptera: Apidae)
    (Entemological Society of America, 1990) Smith, Deborah R.; Brown, Wesley M.
    Restriction endonuclease cleavage maps of mitochondrial DNAs of Scandinavian Apis mellifera mellifera L., of German, Austrian, and Yugoslavian A. m. carnica Pollman, and of Austrian "Nigra" honey bees are compared with previously published maps of mitochondrial DNA from North American bees of European ancestry and Brazilian Africanized bees. A. m. mellifera mitochondrial DNA is characterized by a pattern of cleavage sites unique among the honey bee populations thus far investigated. Variation in size of the mitochondrial DNA molecule is common among families (hives) of A. m. mellifera and appears to involve several distinct regions that span a region at least 5.1 kilobase pairs in length. Some elements of size variation seem to be confined to the A. m. mellifera population, whereas others are shared with Africanized bees. A. m. carnica mitochondrial DNA is characterized by a pattern of cleavage sites, which differs from that of A. m. mellifera and the Africanized bees but is similar to that of the domestic North American bees of European ancestry.
  • Publication
    Explorando el papel del intercambio virtual en el desarrollo de la competencia translingüística y transcultural
    (Johns Hopkins University Press, 2009-09) Rossomondo, Amy E.; Alonso, Maria
    El presente artículo ofrece una exploración de los objetivos propuestos para las instituciones postsecundarias en el informe del 2007 del MLA sobre el futuro del estudio de las lenguas extranjeras en el siglo XXI en los EE. UU. Se dedica atención especial al desarrollo de la competencia translingüística y transcultural a todos niveles de estudios y sus implicaciones para el diseño curricular. Específicamente se examina el papel de los intercambios virtuales con base Web y su posible contribución a la consecución de los objetivos señalados por el MLA por medio de la presentación y análisis de resultados de Proyecto Conexiones, un intercambio entre estudiantes universitarios en los EE.UU. y estudiantes universitarios en Costa Rica. Después de analizar los resultados, se ofrece una discusión de la viabilidad de implementar los intercambios virtuales en instituciones de recursos limitados y posibles alternativas para cursos y programas de nivel básico.
  • Publication
    Behavioral Interactions between Parasites and Hosts: Host Suicide and the Evolution of Complex Life Cycles
    (University of Chicago Press, 1980-07-01) Smith, Deborah R.
    The study of parasites and their hosts has typically focused on the physiological, morphological, and immunological adaptations to parasitism, adaptations which the parasite employs to survive and reproduce in the host and those used by the host in self-defense. This paper explores instead some of the behavioral aspects of the parasite-host relationship. The parasite can alter the behavior of the host in ways which will facilitate dispersal of parasite propagules to new hosts or increase the amount of energy available for the parasite's growth. The host in turn can employ behavioral defense mechanisms as well as the more familiar physiological and immunological defense mechanisms. In one of the most interesting forms of behavioral defense, a host may use its own death to increase its inclusive fitness. Since some types of parasitic infections cause death or sterility of the host they also result in the host's genetic death. Although the host may be unable to affect its individual reproductive fitness it can affect its inclusive fitness. The host can change the time and nature of its death; it can "commit suicide," or behave aberrantly and increase the probability of death by predation, thus preventing the maturation of its parasite and lowering the risk of parasitic infection for other members of the host specie^. If the mature parasite would have been more likely to infect the host's kin than nonkin, the host's suicidal behavior will increase its inclusive fitness and thus have a positive selective value. I will first discuss four types of parasitic life cycles and behavioral interactions between these parasites and their hosts. The phenomenon of host suicide and situations where this phenomenon might be expected to occur will be discussed in detail. Finally, I will outline the role that host suicide may have played in the evolution of complex life cycles.
  • Publication
    Challenges for Coring Deep Permafrost on Earth and Mars
    (Mary Ann Liebert, 2008-08-04) Pfiffner, S. M.; Onstott, T. C.; Ruskeeniemi, T.; Talikka, M.; Bakermans, C.; McGown, D.; Chan, E.; Johnson, A.; Phelps, T. J.; Puil, M. Le; Difurio, S. A.; Pratt, L. M.; Stotler, R.; Frape, S.; Telling, J.; Lollar, B. Sherwood; Neill, I.; Zerbin, B.
    A scientific drilling expedition to the High Lake region of Nunavut, Canada, was recently completed with the goals of collecting samples and delineating gradients in salinity, gas composition, pH, pe, and microbial abundance in a 400 m thick permafrost zone and accessing the underlying pristine subpermafrost brine. With a triple-barrel wireline tool and the use of stringent quality assurance and quality control (QA/QC) protocols, 200 m of frozen, Archean, mafic volcanic rock was collected from the lower boundary that separates the permafrost layer and subpermafrost saline water. Hot water was used to remove cuttings and prevent the drill rods from freezing in place. No cryopegs were detected during penetration through the permafrost. Coring stopped at the 535 m depth, and the drill water was bailed from the hole while saline water replaced it. Within 24 hours, the borehole iced closed at 125 m depth due to vapor condensation from atmospheric moisture and, initially, warm water leaking through the casing, which blocked further access. Preliminary data suggest that the recovered cores contain viable anaerobic microorganisms that are not contaminants even though isotopic analyses of the saline borehole water suggests that it is a residue of the drilling brine used to remove the ice from the upper, older portion of the borehole. Any proposed coring mission to Mars that seeks to access subpermafrost brine will not only require borehole stability but also a means by which to generate substantial heating along the borehole string to prevent closure of the borehole from condensation of water vapor generated by drilling. Astrobiology 8, 623–638.
  • Publication
    Genetic Relatedness Among Co-Foundresses of Two Desert Ants, Veromessor Pergandei and Acromyrmex Versicolor (Hymenoptera: Formicidae)
    (Hindawi Publishing Corporation, 1988-09-20) Hagen, Robert H.; Smith, Deborah R.; Rissing, Steven W.
    No abstract is available for this item.
  • Publication
    A New Colonial Anelosimus Spider From Suriname (Araneae: Theridiidae)
    (Hindawi Publishing Corporation, 1982-09-14) Levi, Herbert W.; Smith, Deborah R.
    No abstract is available for this item.
  • Publication
    Predation by Argyrodes (Theridiidae) on Solitary and Communal Spiders
    (Hindawi Publishing Corporation, 1980-05-01) Smith, Deborah R.
    No abstract is available for this item.
  • Publication
    Evolution of the complementary sex-determination gene of honey bees: Balancing selection and trans-species polymorphisms
    (Cold Spring Harbor Laboratory Press, 2006-10-25) Cho, Soochin; Huang, Zachary Y.; Green, Daniel R.; Smith, Deborah R.; Zhang, Jianzhi
    The mechanism of sex determination varies substantively among evolutionary lineages. One important mode of genetic sex determination is haplodiploidy, which is used by ∼20% of all animal species, including >200,000 species of the entire insect order Hymenoptera. In the honey bee Apis mellifera, a hymenopteran model organism, females are heterozygous at the csd (complementary sex determination) locus, whereas males are hemizygous (from unfertilized eggs). Fertilized homozygotes develop into sterile males that are eaten before maturity. Because homozygotes have zero fitness and because common alleles are more likely than rare ones to form homozygotes, csd should be subject to strong overdominant selection and negative frequency-dependent selection. Under these selective forces, together known as balancing selection, csd is expected to exhibit a high degree of intraspecific polymorphism, with long-lived alleles that may be even older than the species. Here we sequence the csd genes as well as randomly selected neutral genomic regions from individuals of three closely related species, A. mellifera, Apis cerana, and Apis dorsata. The polymorphic level is approximately seven times higher in csd than in the neutral regions. Gene genealogies reveal trans-species polymorphisms at csd but not at any neutral regions. Consistent with the prediction of rare-allele advantage, nonsynonymous mutations are found to be positively selected in csd only in early stages after their appearances. Surprisingly, three different hypervariable repetitive regions in csd are present in the three species, suggesting variable mechanisms underlying allelic specificities. Our results provide a definitive demonstration of balancing selection acting at the honey bee csd gene, offer insights into the molecular determinants of csd allelic specificities, and help avoid homozygosity in bee breeding.
  • Publication
    A Test of Baker’s Law: Breeding Systems and the Radiation of Tolpis (Asteraceae) in the Canary Islands
    (University of Chicago Press, 2008-07-01) Crawford, Daniel J.; Archibald, Jenny K.; Stoermer, Danielle; Mort, Mark E.; Kelly, John K.; Santos-Guerra, Arnoldo
    Baker’s law posits that self‐compatible (SC) plants will be more successful than self‐incompatible (SI) plants in long‐distance colonization because a single propagule can establish a viable population. Oceanic islands represent ideal systems to test Baker’s law because insular lineages have, without question, originated from long‐distance dispersal. The dilemma of Baker’s law is that one propagule of an SC plant would establish a population with low genetic diversity, which could limit subsequent evolution. By contrast, a single propagule from an SI ancestor, having originated from an outcrossing source population, would provide more diversity but could not undergo sexual reproduction. We examined this issue by studying the breeding system of members of the flowering plant genus Tolpis (Asteraceae), a small (nine to 13 species), monophyletic lineage in the Canary Islands archipelago. A combination of floral morphology, pollen‐ovule ratio, autogamous seed set, and genetic data indicates that only one endemic species (T. coronopifolia) is effectively SC. The remainder of the endemics are pseudo‐self‐compatible, i.e., are largely SI but capable of low levels of seed set from self‐fertilization. Pseudo‐self‐compatibility remedies the dilemma of Baker’s law: a single propagule can establish a sexual population and yet have sufficient variation to facilitate diversification.
  • Publication
    Biosystematic Analysis of the Cystopteris tennesseensis (Dryopteridaceae) Complex
    (Missouri Botanical Society, 1990-01-01) Haufler, Christopher H.; Windham, Michael D.; Ranker, Thomas A.
    The allotetraploid Cystopteris tennesseensis and its putative diploid progenitors, C. bulbifera and C. protrusa, constitute the C. tennesseensis complex. Although previous studies provided evidence of morphological, ecological, and chromosomal differences among the members of this complex, puzzling morphological variability precluded consistent identification and treatment of the taxa. The current study combined morphometric analyses with surveys of chromosomal, isozymic, and gametophytic features and supported past treatments of the complex as three separate species. The diploids shared no allozymes for the nine enzymes examined, and meiotic analyses of triploid hybrids with C. tennesseensis provided additional evidence that the diploid genomes are nonhomologous. Because C. tennesseensis has a relatively narrow range and contains isozymic profiles that are consistently additive of diploid patterns, we suggest that this allopolyploid is a relatively young species. Isozymic variation in the tetraploid parallels that observed in the diploids, implying that genetic variability was introduced through recurrent hybridization. Analyses of isozymic data and gametophytic features indicated that the diploids outcross frequently and thus may form hybrids readily when sympatric with the tetraploid. In part because of these characteristics, precise identification of species and hybrids in this complex is difficult and depends on evaluation of cryptic features.
  • Publication
    Homospory 2002: An Odyssey of Progress in Pteridophyte Genetics and Evolutionary Biology
    (American Institute of Biological Sciences, 2002-01-01) Haufler, Christopher H.
    No abstract is available for this item.
  • Publication
    Phylogenetic Relationships of the Enigmatic Malesian Fern Thylacopteris (Polypodiaceae, Polypodiidae)
    (University of Chicago Press, 2004-11-01) Schneider, Harald; Janssen, Thomas; Hovenkamp, Peter H.; Smith, Alan R.; Cranfill, Raymond; Haufler, Christopher H.; Ranker, Thomas A.
    Thylacopteris is the sister to a diverse clade of polygrammoid ferns that occurs mainly in Southeast Asia and Malesia. The phylogenetic relationships are inferred from DNA sequences of three chloroplast genome regions (rbcL, rps4, rps4‐trnS IGS) for 62 taxa and a fourth cpDNA sequence (trnL‐trnF IGS) for 35 taxa. The results refute previously proposed close relationships to Polypodium s.s. but support suggested relationships to the Southeast Asiatic genus Goniophlebium. In all phylogenetic reconstructions based on more than one cpDNA region, we recovered Thylacopteris as sister to a clade in which Goniophlebium is in turn sister to several lineages, including the genera Lecanopteris, Lepisorus, Microsorum, and their relatives. Goniophlebium and allies comprise a significant component of vascular fern epiphytes in the rain forests of Southeast Asia and Malesia. The relationships of the genus Thylacopteris as at the base of the clade comprising the genera Goniophlebium, Lecanopteris, Lepisorus, Microsorum, and their relatives indicate that this entire lineage arose in Malesia and subsequently dispersed to continental Asia, Australia, the Pacific, and Africa.
  • Publication
    Patterns of Genetic Variation in Southern Appalachian Populations of Athyrium filix‐femina var. asplenioides (Dryopteridaceae)
    (University of Chicago Press, 2005-09-01) Sciarretta, Kimberly L.; Arbuckle, Erin Potter; Haufler, Christopher H.; Werth, Charles R.
    Allozyme variation (17 loci coding 11 enzymes) was investigated in 14 populations of the fern Athyrium filix‐femina var. asplenioides arrayed at differing elevations and latitudes in the southern Appalachians. Allozyme fingerprints showed that asplenioides individuals comprise meandering, overlapping clones usually ≤3 m in extent, occasionally forming larger clones of up to 17 m. Levels of genetic variability in populations (means: , , ) were near the averages for both ferns and seed plants. General conformance to Hardy‐Weinberg expectations indicated a predominantly outcrossing mating system. Hierarchical F statistic analysis and occasional deficits and excesses of heterozygotes indicated population substructure. Similar allele frequencies across all populations resulted in low to moderate values (mean ; ) and high values of genetic similarity (mean ; mean ). Hierarchical analysis indicated that neither regional proximity ( ) nor elevation ( ) contributed substantially to divergence among populations ( ), a result corroborated by UPGMA analysis that clustered together populations from different regions and of different elevational class. Southern Appalachian asplenioides differed from more eastern asplenioides populations of the piedmont and coastal plain in having higher frequencies of Pgm‐2c and Tpi‐2B, alleles characteristic of the more northern variety angustum. Nonetheless, genetic distinctness of the two varieties was maintained. We hypothesize that higher frequencies of angustum alleles in the southern Appalachian asplenioides populations are the result of introgression from angustum that persisted at high elevations as both taxa migrated northward following the retreat of the Wisconsinan glacier.
  • Publication
    Population Structure in an Indian Cooperative Spider, Stegodyphus sarasinorum Karsch (Eresidae)
    (American Arachnological Society, 1994-01-01) Engel, Michael S.; Smith, Deborah R.
    Twenty-nine colonies of a population of the cooperative spider Stegodyphus sarasinorum Karsch (Eresidae), from two sites in Bangalore, Karnataka State, India, were examined using protein allozyme electrophoresis . Thirty-five enzyme systems were examined . Twenty-two enzymes (the products of 25 putative loci) gave scorable results . Lactate dehydrogenase (LDH) and glucose-6-phosphate dehydrogenase (G6PDH) werepolymorphic with two alleles each; hexokinase exhibited uninterpretable variation . The rest were monomorphic. One LDH allele was found at only one of two collection sites, and one G6PDH allele was found only at the other collection site. The pattern of variation in S. sarasinorum is similar to that found in three other studies of cooperative spiders : extreme population subdivision, with most colonies consisting of identical homozygotes.
  • Publication
    First Comes Social Networking, Then Comes Marriage? Characteristics of Americans Married 2005–2012 Who Met Through Social Networking Sites
    (Mary Ann Liebert, 2014-05-10) Hall, Jeffrey A.
    Although social networking sites (SNS) have become increasingly prevalent and integrated into the lives of users, the role of SNS in courtship is relatively unknown. The present manuscript reports on the characteristics of Americans married between 2005 and 2012 who met through SNS drawn from a weighted national sample (N=18,527). Compared to other online meetings (i.e., dating sites, online communities, one-on-one communication), individuals who met through SNS were younger, married more recently, and were more likely to be African American. Compared with offline meetings, individuals who met through SNS were more likely to be younger, male, African American and Hispanic, married more recently, and frequent Internet users with higher incomes. Trends suggest an increasing proportion of individuals are meeting using SNS, necessitating further research on factors that influence romantic relational development through SNS.
  • Publication
    Offensive jokes: How do they impact long-term relationships?
    (De Gruyter, 2010-01-01) Hall, Jeffrey A.; Sereno, Ken
    This article explores the impact of the use of negative humor on relational satisfaction and the importance of humor in long-term relationships from a coorientation perspective. Dyadic data from 123 couples were gathered using a survey measuring positive and negative humor use. These data were analyzed using structural equations modeling and the Actor-Partner Independence Model (Kenny et al., Dyadic data analysis, The Guilford Press, 2006: 144). Negative humor weakly predicted relational outcomes, but was valuable when partners saw themselves as possessing a shared sense of humor. Men acknowledge that their own public negative humor use negatively impacts the importance of humor in their relationship. Perceived similarity in negative humor use positively predicts relational satisfaction for both partners, and positively predicts the importance of humor for men, regardless of how much positive humor the couple uses. Accurately knowing a partner's negative humor use, or having greater understanding, negatively predicted relational outcomes.
  • Publication
    An analysis of humor orientation on Facebook: A lens model approach
    (De Gruyter, 2014-02-01) Pennington, Natalie; Hall, Jeffrey A.
    This article presents the results of a mixed method analysis of the use and perception of humor orientation (HO) on Facebook (FB) profiles (N = 100). Results of the lens model analysis suggest that a variety of profile cues, not just those directly related to humor, are used by FB users to demonstrate HO and by observers to perceive HO. Cues used by profile owners and perceived by strangers as indicative of a humorous disposition include: status updates that contained relational talk, humor in profile pictures, humor in quotes, the number of times FB friends “liked” status updates, and the number of unique friends who commented on status updates. Additionally, political talk in status updates was negatively related to users' HO and observers' impressions of users' HO. A qualitative thematic analysis of the FB profiles was then conducted. Those analyses suggested that cues diagnostic of users' HO thematically focused on daily life events, popculture references, and selfrelated anecdotes. Implications for the expression of and perception of humor on FB are discussed.
  • Publication
    Transport properties of CO2-expanded acetonitrile from molecular dynamics simulations
    (American Institute of Physics, 2007-02-21) Houndonougbo, Yao; Laird, Brian Bostian; Kuczera, Krzysztof
    Carbon-dioxide-expanded liquids, which are mixtures of organic liquids and compressed CO2, are novel media used in chemical processing. The authors present a molecular simulation study of the transport properties of liquid mixtures formed by acetonitrile and carbon dioxide, in which the CO2 mole fraction is adjusted by changing the pressure, at a constant temperature of 298K. They report values of translational diffusion coefficients, rotational correlation times, and shear viscosities of the liquids as function of CO2 mole fraction. The simulation results are in good agreement with the available experimental data for the pure components and provide interesting insights into the largely unknown properties of the mixtures, which are being recognized as important novel materials in chemical operations. We find that the calculated quantities exhibit smooth variation with composition that may be represented by simple model equations. The translational and rotational diffusion rates increase with CO2 mole fraction for both the acetonitrile and carbon dioxide components. The shear viscosity decreases with increasing amount of CO2, varying smoothly between the values of pure acetonitrile and pure carbon dioxide. Our results show that adjusting the amount of CO2 in the mixture allows the variation of transport rates by a factor of 3–4 and liquidviscosity by a factor of 8. Thus, the physical properties of the mixture may be tailored to the desired range by changes in the operating conditions of temperature and pressure.
  • Publication
    Influence of temperature and viscosity on anthracene rotational diffusion in organic solvents: Molecular dynamics simulations and fluorescence anisotropy study
    (American Institute of Physics, 1997-01-01) Jas, Gouri S.; Wang, Yan; Pauls, Steven W.; Johnson, Carey K.; Kuczera, Krzysztof
    Molecular dynamics simulations and fluorescenceanisotropy decay measurements are used to investigate the rotational diffusion of anthracene in two organic solvents—cyclohexane and 2-propanol—at several temperatures. Molecular dynamics simulations of 1 ns length were performed for anthracene in cyclohexane (at 280, 296, and 310 K) and in 2-propanol (at 296 K). The calculated time constants for reorientation of the short in-plane axis were 7–9 and 11–16 ps at 296 K in cyclohexane and 2-propanol, respectively, in excellent agreement with corresponding fluorescence depolarization measurements of 8 and 14 ps. The measured rotational reorientation times and the calculated average rotational diffusion coefficients varied in accord with Debye–Stokes–Einstein theory. Their magnitudes were close to values predicted for an ellipsoid of shape and size equivalent to an anthracene molecule, and exhibited predictable variation with external conditions—increasing with temperature and decreasing with solventviscosity. However, analysis of the calculated rotational diffusion coefficients for the individual molecular axes gave a more complex picture. The diffusion was highly anisotropic and changes in temperature and solvent type led to nonuniform variation of the diffusion coefficients. The nature of these changes was rationalized based on analysis of variation of solvation patterns with temperature and solvent.
  • Publication
    The Low-Level Atmospheric Circulation near Tongoy Bay–Point Lengua de Vaca (Chilean Coast, 30°S)
    (American Meteorological Society, 2011-11-01) Rahn, David A.; Garreaud, René D.; Rutllant, José A.
    Strong southerly, terrain parallel winds often occur along the coast of north-central Chile (25°–35°S) embedded in the marine atmospheric boundary layer and the lower part of the capping temperature inversion. Their offshore structure and variability have received considerable attention because of the effect on open-ocean processes and connection with the southeast Pacific cloud layer. Mesoscale low-level circulations linked to the coastal topography (e.g., coastal jets and sea breeze) are less studied in Chile, but are particularly relevant as they alter the upper-ocean circulation and the cloud pattern in the nearshore strip. Surface, radiosonde, and airborne meteorological observations near point Lengua de Vaca (LdV)–Tongoy Bay (TB) at 30°S are used alongside numerical modeling to understand the local circulation near a prominent upwelling center. Most observations were gathered during the Variability of the American Monsoon Systems (VAMOS) Ocean–Cloud–Atmosphere–Land Study Chilean Upwelling Experiment (VOCALS-CUpEx) during two weeks in late spring 2009. The regional topography resembles other major capes, but south of TB and east of LdV there is a low (100–300 m), dry marine terrace bounded by high elevation at the coast (~600 m) and farther inland. Coastal soundings 25 km upstream of LdV revealed a southerly wind maximum near the surface and another at 900 m separated by a destabilized layer, deviating from the two-layer model often applied to coastal flow. In the morning a shallow sea breeze penetrates from TB to the marine terrace, but is overridden by southerly flow in the afternoon. Furthermore, between 400 and 900 m, warm continental air is advected from over the marine terrace creating a residual boundary layer over TB. Concurrent with slower changes offshore, the low-level warming over TB leads to a marked cross-shore pressure gradient enhancing the coastal jet just north of LdV.