Digital Commons Network^™

Invasiveness Of Some Biological Control Insects And Adequacy Of Their Ecological Risk Assessment And Regulation, Svata M. Louda, Amy E. Arnett, Tatyana A. Rand, F. L. Russell

School of Biological Sciences: Faculty Publications

The problem of invasive species has reignited interest in biological control as a management tool. Classical biological control involves deliberate release of exotic natural enemies into new environments in an attempt to limit the density of an invasive species. Persistent, sustained limitation of invasive species by coevolved natural enemies is a seductive concept. Evidence now suggests, however, that biological control through the release of natural enemies can carry unanticipated ecological risks. There have been ecological side effects of distributing a deliberately introduced weevil (Rhinocyllus conicus) and an adventitious weevil (Larinus planus) for the biological control of …

Improving Precision And Reducing Bias In Biological Surveys: Estimating False-Negative Error Rates, Andrew J. Tyre, Brigitte Tenhumberg, Scott A. Field, Darren Niejalke, Kirsten Parris, Hugh P. Possingham

School of Biological Sciences: Faculty Publications

The use of presence/absence data in wildlife management and biological surveys is widespread. There is a growing interest in quantifying the sources of error associated with these data. We show that false-negative errors (failure to record a species when in fact it is present) can have a significant impact on statistical estimation of habitat models using simulated data. Then we introduce an extension of logistic modeling, the zero-inflated binomial (ZIB) model that permits the estimation of the rate of false-negative errors and the correction of estimates of the probability of occurrence for false-negative errors by using repeated visits to the …

An Analysis Of The Secondary Structure Of The Mitochondrial Large Subunit Rrna Gene (16s) In Spiders And Its Implications For Phylogenetic Reconstruction, Stacey Dewitt Smith, Jason E. Bond

School of Biological Sciences: Faculty Publications

We investigated the pattern of molecular variation with respect to secondary structure in the 16S ribosomal RNA gene and its phylogenetic implications for arachnids with a focus on spiders. Based on a model by Gutell et al. (1996), secondary structures were proposed for the 3' half of 16S in the mygalomorph spider Aptostichus atomarius. Models were also constructed for a hypervariable length of the 16S in three other arachnids, which revealed a trend of stem and loop reduction in more advanced arachnids. Using a simple statistical approach to compare functional regions, we found that internal and external loops are …

The Turn Of The Sword: Length Increases Male Swimming Costs In Swordtails, Alexandra Basolo, Giollermina Alcaraz

School of Biological Sciences: Faculty Publications

Sexual selection via female mate choice can result in the evolution of elaborate male traits that incur substantial costs for males. Despite increased interest in how female mating preferences contribute to the evolution of male traits, few studies have directly quantified the locomotor costs of such traits. A sexually selected trait that could affect movement costs is the sword exhibited by male swordtail fishes: while longer swords may increase male mating success, they could negatively affect the hydrodynamic aspects of swimming activities. Here, we examine the energetic costs of the sword in Xiphophorus montezumae by experimentally manipulating sword length and …

Food Supplements Modulate Changes In Leucocyte Numbers In Breeding Male Ground Squirrels, Gwendolyn C. Bachman

School of Biological Sciences: Faculty Publications

Immunosuppression may be an important cost of reproduction in breeding males. It can result from elevated levels of testosterone or stress hormones and may serve to lower the energetic cost of maintaining immune function at a time of high demand. This suggests that greater access to energy resources could reduce immunosuppression as a cost of reproduction, minimizing the trade-off between energetic investment in current reproductive effort and survival. I examined the impact of food availability on immune function by provisioning male Belding’s ground squirrels in the field from the time they emerged from hibernation to the start of breeding. Temporal …

Ontogenetic Shift In Buoyancy And Habitat In The Antarctic Toothfish, Dissostichus Mawsoni (Perciformes: Nototheniidae), Thomas J. Near, Sabrina E. Russo, Christopher D. Jones, Arthur L. Devries

School of Biological Sciences: Faculty Publications

Buoyancy measurements and depth of capture were taken on 70 individuals of Dissostichus mawsoni collected from the Southern Scotia Arc and McMurdo Sound, Antarctica, to examine the effect of age on buoyancy and habitat use. Standard lengths (SL) ranged from 10.4 to 138.0 cm. Juveniles were not buoyant (heavy in water), whereas adults were neutrally buoyant. The slope of the relationship between buoyancy and SL was significantly negative for juveniles (individuals less than 81 cm SL), but there was no significant relationship for adults (individuals greater than 81 cm SL). These results demonstrate an ontogenetic shift in buoyancy. For juveniles, …

Cytotypes Of Andropogon Gerardii Vitman (Poaceae): Fertility And Reproduction Of Aneuploids, Guillermo A. Norrmann, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

In many North American prairies, populations of Andropogon gerardii Vitman (Poaceae) are composed of hexaploid and enneaploid cytotypes (2n = 60, 90), with intermediates occurring occasionally. Under controlled pollination, the two common cytotypes can be crossed, producing progeny with a range of chromosome numbers. In an investigation of fertility and compatibilities of intermediate cytotypes, individuals with chromosome numbers between 60 and 90 were crossed with each other, with the 2n = 60 and 90 cytotypes, and with South American Andropogon species having 60 chromosomes. Regardless of cytotype, all A. gerardii plants had some fertility and virtually all crosses …

Dynamic Versus Instantaneous Models Of Diet Choice, Brian O. Ma, Peter A. Abrams, Chad Brassil

School of Biological Sciences: Faculty Publications

We investigate the dynamics of a series of two-prey-one predator models in which the predator exhibits adaptive diet choice based on the different energy contents and/or handling times of the two prey species. The predator is efficient at exploiting its prey and has a saturating functional response; these two features combine to produce sustained population cycles over a wide range of parameter values. Two types of models of behavioral change are compared. In one class of models (“instantaneous choice”), the probability of acceptance of the poorer prey by the predator instantaneously approximates the optimal choice, given current prey densities. In …

Targeted Disruption Of The Α-Amylase Gene In The Hyperthermophilic Archaeon Sulfolobus Solfataricus, Penny Worthington, Viet Hoang, Francisco Perez-Pomares, Paul H. Blum

School of Biological Sciences: Faculty Publications

Sulfolobus solfataricus secretes an acid-resistant _-amylase (amyA) during growth on starch as the sole

carbon and energy source. Synthesis of this activity is subject to catabolite repression. To better understand

_-amylase function and regulation, the structural gene was identified and disrupted and the resulting mutant

was characterized. Internal _-amylase peptide sequences obtained by tandem mass spectroscopy were used to

identify the amyA coding sequence. Anti-_-amylase antibodies raised against the purified protein immunoprecipitated

secreted _-amylase activity and verified the enzymatic identity of the sequenced protein. A new

gene replacement method was used to disrupt the amyA coding sequence by …

Single-Cell Protein Profiling Of Wastewater Enterobacterial Communities Predicts Disinfection Efficiency, Gomathinayagam Ponniah, Han Chen, Ronda Michielutti, Nancy Salonen, Paul H. Blum

School of Biological Sciences: Faculty Publications

The efficiency of enterobacterial disinfection is dependent largely on enterobacterial community physiology. However, the relationship between enterobacterial community physiology and wastewater processing is unclear. The purpose of this study was to investigate this relationship. The influence of wastewater treatment processes on enterobacterial community physiology was examined at the single-cell level by using cultureindependent methods. Intracellular concentrations of two conserved proteins, the growth-related protein Fis and the stationary-phase protein Dps, were analyzed by epifluoresence microscopy of uncultivated cells by using enterobacterial group-specific polyclonal fluorochrome-coupled antibodies. Enterobacterial single-cell community protein profiles were distinct for different types of biological treatment. The differences were …

Large-Scale Cultivation Of Acidophilic Hyperthermophiles For Recovery Of Secreted Proteins, Penny Worthington, Paul H. Blum, Francisco Perez-Pomares, Tom Elthon

School of Biological Sciences: Faculty Publications

An electric water heater was modified for large-scale cultivation of aerobic acidophilic hyperthermophiles to enable recovery of secreted proteins. Critical changes included thermostat replacement, redesign of the temperature control circuit, and removal of the cathodic anticorrosion system. These alterations provided accurate temperature and pH control. The bioreactor was used to cultivate selected strains of the archaeon Sulfolobus solfataricus and other species within this genus. Reformulation of a basal salts medium facilitated preparation of large culture volumes and eliminated sterilization-induced precipitation of medium components. Substrate induction of synthesis of the S. solfataricus-secreted alpha-amylase during growth in a defined medium …

Putative Subunits Of The Maize Origin Of Replication Recognition Complex Zmorc1±Zmorc5, Xiaohong Witmer, Raul Alvarez-Venegas, Phillip San-Miguel, Olga Danilevskaya, Zoya Avramova

School of Biological Sciences: Faculty Publications

The finding in animal species of complexes homologous

to the products of six Saccharomyces cerevisiae

genes, origin of replication recognition

complex (ORC), has suggested that ORC-related

mechanisms have been conserved in all eukaryotes.

In plants, however, the only cloned putative homologs

of ORC subunits are the Arabidopsis ORC2 and

the rice ORC1. Homologs of other subunits of plant

origin have not been cloned and characterized. A

striking observation was the absence from the

Arabidopsis genome of an obvious candidate genehomolog

of ORC4. This fact raised compelling

questions of whether plants, in general, and

Arabidopsis, in particular, may have lost the …

Codon Usage, Estuko N. Moriyama

Papers in Genetics

The genetic codes have degeneracy; that is, most amino acids (18 out of 20 in the universal genetic code) are encoded by more than one codon. Codons encoding the same amino acid are called synonymous codons. Both in prokaryotic and eukaryotic genes, the synonymous codons are not used with equal frequencies.

Life Span Extension Of Drosophila Melanogaster: Genetic And Population Studies, Lawrence G. Harshman

Lawrence G. Harshman Publications

During the past two decades, genetic studies of model organisms have been the most important tool underlying advances in understanding the biological basis of aging and longevity. Drosophila melanogaster, the geneticist's "fruit fly," is a model organism because it has been the focus of genetic studies for more than 90 years. This review argues that studies on D. melanogaster will make an especially important contribution to the field of aging and longevity at the intersection of research on genetics, complex traits, and fly populations.

Five approaches have been used to study the genetics of longevity of D. melanogaster: …

Eight Gram-Negative Bacteria Are 10,000 Times More Sensitive To Cationic Detergents Than To Anionic Detergents, Soumitra Rajagopal, Nicole Eis, Kenneth Nickerson

Kenneth Nickerson Papers

In liquid culture, eight typical Gram-negative bacteria were ca. 10,000-fold more sensitive to cationic detergents than to the anionic detergent sodium dodecyl sulfate. Cetyltrimethylammonium bromide (CTAB) was inhibitory at concentrations ranging from 0.0006% to 0.01%. Four pseudomonads able to form biofilms were ca. 1000-fold more resistant to CTAB on Luria–Bertani agar plates than they were in liquid culture. A lasI mutant of Pseudomonas aeruginosa was only able to tolerate 0.1% CTAB on Luria–Bertani agar plates but could tolerate 5% CTAB when supplemented with homoserine lactone containing culture supernatants.

En culture liquide, huit bactéries Gram négatif typiques étaient ca. 10,000 fois …

Searching By Rules: Pigeons’ (Columba Livia) Landmark-Based Search According To Constant Bearing Or Constant Distance, Marcia C. Spetch, Tiana B. Rust, Alan Kamil, Juli E. Jones

Papers in Behavior in Biological Sciences

Pigeons (Columba livia) searched for a goal location defined by a constant relative spatial relationship to 2 landmarks. For one group, landmark-to-goal bearings remained constant while distance varied. For another group, landmark-to-goal distances remained constant while direction varied. Birds were trained with 4 interlandmark distances and then tested with 5 novel interlandmark distances. Overall error magnitude was similar across groups and was larger than previously reported for Clark’s nutcrackers (Nucifraga columbiana). During training, error magnitude increased with interlandmark distance for constant-bearing but not constant-distance birds. Both groups searched less accurately along the axis parallel to landmarks …

Nontarget Effects—The Achilles’ Heel Of Biological Control? Retrospective Analyses To Reduce Risk Associated With Biocontrol Introductions, Svata M. Louda, R. W. Pemberton, M. T. Johnson, P. A. Follett

Papers in Ecology

Controversy exists over ecological risks in classical biological control. We reviewed 10 projects with quantitative data on nontarget effects. Ten patterns emerged: (a) Relatives of the pest are most likely to be attacked; (b) host-specificity testing defines physiological host range, but not ecological range; (c) prediction of ecological consequences requires population data; (d) level of impact varied, often in relation to environmental conditions; (e) information on magnitude of nontarget impact is sparse; ( f ) attack on rare native species can accelerate their decline; (g) nontarget effects can be indirect; (h) agents disperse from agroecosystems; (i) whole assemblages of species …

A New Species Of Laelapine Mite (Acari: Parasitiformes: Laelapidae) Associated With Proechimys Dimidiatus In The Atlantic Forests Of Brazil, Donald Gettinger, Helena Godoy Bergallo

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Tur megistoproctus, a new species of Laelapinae, is described from the pelage of the echimyid rodent Proechimys dimidiatus from the Atlantic forests of Ilha Grande, south of Rio de Janeiro. Measurements and illustrations are included for females and males. Another laelapine mite species, Tur turki Fonseca, co-occurred with T.megistoproctus in our studies and was recorded from the same host individuals and localities. These 2 laelapine mite species appear to be exclusively associated with a complex of echimyid rodent species (subgenus Trinomys) in the Atlantic forests of southeastern Brazil.

A New Species Of Neotropical Laelapine Mite (Acari: Parasitiformes, Laelapidae) From The Marsupial Monodelphis Americana, Donald Gettinger, Fernanda Martins-Hatano

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Androlaelaps ilhacardosoi, a new species of Laelapinae, is described from the pelage of a 3-lined marsupial, Monodelphis americana, collected on Ilha Cardoso, São Paulo State, Brazil. The description is based on the female, and the systematics of laelapine mites associated with neotropical marsupials is discussed.

Phylogenetic Analysis Of The Metastrongyloidea (Nematoda: Strongylida) Inferred From Ribosomal Rna Gene Sequences, Ramon A. Carreno, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Phylogenetic relationships among nematodes of the strongylid superfamily Metastrongyloidea were analyzed using partial sequences from the large-subunit ribosomal RNA (LSU rRNA) and small-subunit ribosomal RNA (SSU rRNA) genes. Regions of nuclear ribosomal DNA (rDNA) were amplified by polymerase chain reaction, directly sequenced, aligned, and phylogenies inferred using maximum parsimony. Phylogenetic hypotheses inferred from the SSU rRNA gene supported the monophyly of representative taxa from each of the 7 currently accepted metastrongyloid families. Metastrongyloid taxa formed the sister group to representative trichostrongyloid sequences based on SSU data. Sequences from either the SSU or LSU RNA regions alone provided poor resolution for …

Effects Of Oxide Coating And Selected Cations On Nitrate Reduction By Iron Metal, Yong H. Huang, Tian Zhang, Patrick J. Shea, Steve D. Comfort

Department of Civil and Environmental Engineering: Faculty Publications

Under anoxic conditions, zerovalent iron (Fe⁰) reduces nitrate to and magnetite (Fe₃O₄) is produced at near-neutral pH. removal was most rapid at low pH (2–4); however, the formation of a black oxide film at pH 5 to 8 temporarily halted or slowed reaction unless the system was augmented with Fe²⁺, Cu²⁺, or Al³⁺. Bathing the corroding Fe⁰ in a Fe²⁺ solution greatly enhanced nitrate reduction at near-neutral pH and coincided with the formation of a black precipitate. X-ray diffractometry and scanning electron microscopy confirmed that both …

Where Are The Women Geoscience Professors?, Mary Anne Holmes, Suzanne O'Connel

Department of Earth and Atmospheric Sciences: Faculty Publications

Compiles an extensive set of data on the status of women in the geosciences, identifying successful strategies for increasing diversity as well as obstacles that hinder efforts. The lessons learned and best practices that arise from this report will help geoscientists continue to increase the gender diversity of their community. Some of these lessons also provide insight into ways to improve the racial and ethnic diversity of the geosciences.

Low Fluence, Robert Katz, F. A. Cucinotta

Robert Katz Publications

The question of the appropriate extrapolation to low dose has long been a subject of controversy. A linear no-threshold model is favored by regulatory bodies as the basis of RBE assignments and estimates of radiation hazards to the general population. This model is largely supported by extensive application of the linear-quadratic survival formula "fitted" statistically to a wide variety of experimental data obtained at doses typically exceeding 1 Gy, and then extrapolated to mGy for practical applications, and even to the prediction of hazards from single electrons. Such extrapolations are questionable at best, and may even prove hazardous for risk …

Genetics And Heart Disease, Hassan Chamsi Pasha

Saudi Medical Journal

Production of genome sequence has recently skyrocketed with many advances in the understanding and etiology of certain diseases. Researchers have localized a region of the human genome that plays a role in determining a persons susceptibility to myocardial infarction. A new apolipoprotein gene that influences triglyceride levels in humans is also described. A recent study from Finland showed that certain families are likely to carry a genetic form of insulin resistance syndrome that predisposes them to accelerated atherosclerosis. Researchers identified 3 mutations in the gene producing a protein called metavinculin, which appears to be linked to abnormalities in cellular structures …

Anti-Spasticity Medications, Abdulrahman M. Al-Shahrani

Saudi Medical Journal

Spasticity is common in patients with a variety of central nervous system disorders. It can lead to significant disability or cause complications that may result in severe morbidity. In such patients, treatment of spasticity is warranted. Several oral and parenteral medications are available for use in the treatment of spasticity. This article reviews the pharmacological properties and therapeutic effectiveness of these medications to provide a practical objective guide for physicians who may be involved in the management of spasticity.

Human Physiology, Luke O. Nwoye, Mohammad Mohammad

Saudi Medical Journal

No abstract provided.

Selectivity And Metaplasticity In A Unified Calcium-Dependent Model, Luk C. Yeung, Brian S. Blais, Leon N. Cooper, Harel Z. Shouval

Science and Technology Department Faculty Journal Articles

A unified, biophysically motivated Calcium-Dependent Learning model has been shown to account for various rate-based and spike time-dependent paradigms for inducing synaptic plasticity. Here, we investigate the properties of this model for a multi-synapse neuron that receives inputs with different spike-train statistics. In addition, we present a physiological form of metaplasticity, an activity-driven regulation mechanism, that is essential for the robustness of the model. A neuron thus implemented develops stable and selective receptive fields, given various input statistics

Hyperthermophilic Alpha-Glucosidase Gene And Its Use, Paul Blum

School of Biological Sciences: Faculty Publications

Recombinant, thermostable alpha-glucosidases from archaeal micro-organisms and isolated DNA encoding for such alpha-glucosidases are provided. The isolated DNA is obtained by use of DNA or antibody probes prepared from the DNA encoding S. sulfataricus alpha-glucosidase. Also provided are methods for producing recombinant archaeal thermostable alpha-glucosidase and transformants incorporating thermostable alpha-glucosidase. Autoprocessing of plant tissue through the use of transgenic thermostable glycosyl hydrolases is described.

The Role Of Visual Landmarks In The Avian Familiar Area Map, Richard A. Holland

School of Biological Sciences: Faculty Publications

The question of whether homing pigeons use visual landmarks for orientation from distant, familiar sites is an unresolved issue in the field of avian navigation. Where evidence has been found, the question still remains as to whether the landmarks are used independent of the map and compass mechanism for orientation that is so important to birds. Recent research has challenged the extent to which experiments that do not directly manipulate the visual sense can be used as evidence for compass-independent orientation. However, it is proposed that extending a new technique for research on vision in homing to include manipulation of …

Multistate Estimates Of Survival And Movement In Relation To Colony Size In The Sociable Weaver, Charles R. Brown, Rita Covas, Mark D. Anderson, Mary Bomberger Brown

School of Biological Sciences: Faculty Publications

We estimated survival and movement probabilities in relation to breeding-colony size in the sociable weaver (Philetairus socius) by using multistate statistical methods, in which survival and movement to time t + 1 is conditional on an individual’s colony size at time t. The sociable weaver is a colonial, cooperatively breeding species that builds a massive communal nest, with colony size ranging from fewer than 20 to more than 500 individuals in some areas. We conducted an 8-year capture/mark/re-capture study of sociable weavers near Kimberley, South Africa. By comparing the fit of different multistate models to our data, we found evidence …