Digital Commons Network^™

Functional Copper At The Acetyl-Coa Synthase Active Site, Javier Seravalli, Welwel Gu, Annie Tam, Erick Strauss, Stephen P. Cramer, Stephen W. Ragsdale

Department of Biochemistry: Faculty Publications

The bifunctional CO dehydrogenase/acetyl-CoA synthase (CODH/ACS) plays a central role in the Wood–Ljungdahl pathway of autotrophic CO₂ fixation. A recent structure of the Moorella thermoacetica enzyme revealed that the ACS active site contains a [4Fe-4S] cluster bridged to a binuclear Cu-Ni site. Here, biochemical and x-ray absorption spectroscopic (XAS) evidence is presented that the copper ion at the M. thermoacetica ACS active site is essential. Depletion of copper correlates with reduction in ACS activity and in intensity of the ‘‘NiFeC’’ EPR signal without affecting either the activity or the EPR spectroscopic properties associated with CODH. In contrast, Zn content …

The Many Faces Of Vitamin B12: Catalysis By Cobalamin-Dependent Enzymes, Ruma Banerjee, Stephen W. Ragsdale

Department of Biochemistry: Faculty Publications

Vitamin B₁₂ is a complex organometallic cofactor associated with three subfamilies of enzymes: the adenosylcobalamin-dependent isomerases, the methylcobalamin-dependent methyltransferases, and the dehalogenases. Different chemical aspects of the cofactor are exploited during catalysis by the isomerases and the methyltransferases. Thus, the cobalt-carbon bond ruptures homolytically in the isomerases, whereas it is cleaved heterolytically in the methyltransferases. The reaction mechanism of the dehalogenases, the most recently discovered class of B₁₂ enzymes, is poorly understood. Over the past decade our understanding of the reaction mechanisms of B₁₂ enzymes has been greatly enhanced by the availability of large amounts of enzyme …

Impact Of Fire Management On The Ecology Of Collared Lizard (Crotaphytus Collaris) Populations Living On The Ozark Plateau, Jennifer A. Brisson, Jared L. Strasburg, Alan R. Templeton

School of Biological Sciences: Faculty Publications

Eastern collared lizards (Crotaphytus collaris collaris) on the Ozark Plateau of southern Missouri are restricted to islands of rocky glade habitat located throughout the oak–hickory forests of the region. Human mediated suppression of fire negatively impacts collared lizard populations by permitting the overgrowth and consequent disappearance of this glade habitat and also leads to a dense forest understorey that impedes movement of lizards between glades. We present data examining the effects of a fire management regime on collared lizard populations we monitored via mark/recapture from 1998 to 2001. We demonstrate increased glade-to-glade dispersal, colonization of previously unoccupied glades, …

Native Thistles: Expendable Or Integral To Ecosystem Resistance To Invasion?, Svata M. Louda, Tatyana A. Rand

School of Biological Sciences: Faculty Publications

One way of addressing the question of whether some species are expendable is to ask what role, if any, a minor species, even one that seems obnoxious, plays in the functioning of its community. Thistles (Cirsium spp.) are prickly plants native to North America that are numerically minor and are often considered unattractive or undesirable. So, thistles might be considered expendable. Yet, can we assume that such minor, seemingly undesirable species can be elirninated without disrupting important interdependencies or losing key ecological services? Our long-term studies of thistle-insect interactions are beginning to provide evidence that even such species may …

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 …

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 …

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 …

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 …

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 …

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 …

Testis Size Increases With Colony Size In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown

School of Biological Sciences: Faculty Publications

By using a sample of more than 800 male cliff swallows (Petrochelidon pyrrhonota) that died during a rare climatic event in our Nebraska study area in 1996, we investigated how testis size was related to body size, age, parasite load, a bird’s past colony-size history, and spleen size. Testis volume in-creased with body size. After correcting for body size, testis volume was lowest for birds age 1 and 2 years but did not vary with age for males 3 years old or more. Birds occupying parasite-free (fumigated) colonies had significantly larger testes than did birds at non-fumigated sites. …

Geographic Variation In Song Of The Bright-Rumped Attila (Tyrannidae: Attila Spadiceus): Implications For Species Status, Daniel Leger, D. James Mountjoy

Department of Psychology: Faculty Publications

Bright-rumped Attilas (Attila spadiceus) have two song forms, one sung primarily at dawn, the other primarily during the rest of the day. Both songs consist of a main phrase and an optional terminal phrase. Our recordings of dawn and day songs in Costa Rica were very similar to those made elsewhere in Central America. However, Central American dawn songs were significantly different than dawn songs from South America, both in terms of quantitative features (temporal and frequency variables) and qualitative characteristics (note shape). Day songs from Central and South America were similar. Song differences suggest that the Bright-rumped …

Quaternary Sedimentation And Subsidence History Of Lake Baikal, Siberia, Based On Seismic Stratigraphy And Coring, S. M. Colman, E. B. Karabanov, C. H. Nelson Iii

United States Geological Survey: Staff Publications

The long, continuous, high-latitude, stratigraphic record of Lake Baikal was deposited in three broad sedimentary environments, defined by high-resolution seismic-reflection and coring methods: (1) turbidite depositional systems, by far the most widespread, characterizing most of the margins and floors of the main basins of the lake, (2) large deltas of major drainages, and (3) tectonically or topographically isolated ridges and banks. Holocene sedimentation rates based on radiocarbon ages vary by more than an order of magnitude among these environments, from less than about 0.03 mm/yr on ridges and banks to more than about 0.3 mm/yr on basin floors. Extrapolating these …

Birth Of The Modern Chesapeake Bay Estuary Between 7.4 And 8.2 Ka And Implications For Global Sea-Level Rise, John F. Bratton, Steven M. Colman, E. Robert Thieler, Robert R. Seal Ii

United States Geological Survey: Staff Publications

Two major pulses of sea-level rise are thought to have taken place since the last glacial maximum – meltwater pulses (mwp) 1A (12 cal ka) and 1B (9.5 cal ka). Between mwp 1B and about 6 cal ka, many of the complex coastal ecosystems which ring the world’s oceans began to form. Here we report data for rhenium, carbon isotopes, total organic carbon, and fossil oysters from Chesapeake Bay which span the transition from fresh to brackish water conditions in the bay in the mid- Holocene. These data constrain sea-level change and resulting environmental change in the bay. They indicate …

The Humerus Of Cryptotis Colombiana And Its Bearing On The Species’ Phylogenetic Relationships (Soricomorpha: Soricidae), Neal Woodman, Carlos A. Cuartas-Calle, Carlos A. Delgado-V.

United States Geological Survey: Staff Publications

The Colombian small-eared shrew, Cryptotis colombiana Woodman and Timm, was described from the Colombian Andes in 1993. Its original allocation to the C. nigrescens group recently was questioned based on several cranial characters the species appeared to share with some members of the C. thomasi group. We review characteristics of the C. nigrescens and C. thomasi groups, and we describe the humerus of C. colombiana and the humerus and manus of C. medellinia. The morphology of the humerus joins the suite of characters that supports the hypotheses that C. colombiana is not a member of the C. thomasi group …

Nesting Behavior Of Palila, As Assessed From Video Recordings, Megan E. Laut, Paul C. Banko, Elizabeth M. Gray

United States Geological Survey: Staff Publications

We quantified nesting behavior of Palila (Loxioides bailleui), an endangered Hawaiian honeycreeper, by recording at nests during three breeding seasons using a black-and-white video camera connected to a videocassette recorder. A total of seven nests was observed. We measured the following factors for daylight hours: percentage of time the female was on the nest (attendance), length of attendance bouts by the female, length of nest recesses, and adult provisioning rates. Comparisons were made between three stages of the 40-day nesting cycle: incubation (day 1–day 16), early nestling stage (day 17–day 30 [i.e., nestlings ≤ 14 days old]), and …

Consumption Of Omega-3 Fatty Acid-Enriched Eggs And Serum Lipids In Humans, Ji-Young Lee, Nancy M. Lewis, Sheila Scheideler, Timothy P. Carr

Department of Nutrition and Health Sciences: Faculty Publications

This study examined the effectiveness of consuming omega-3 fatty acid-enriched eggs (Omega Eggs) in increasing total diclary omega-3 fatty acids. Also examined was the impact of Omega Egg consumption on serum lipids. Sixteen hypercholesterolemic men and women with baseline serum total cholesterol concentrations of 5.17-7.76 mmol/L (200-300 mg/dL) followed the National Cholesterol Education Program Step I diet guidelines under the following conditions: (a) Step 1 diet without eggs, (b) Step I diet plus 12 regular eggs per week, and (c) Step I diet plus 12 Omega Eggs per week. The study design was a repeated 3 x 3 Latin square …

Coccidia In The Mammary Glands Of Shrews (Order: Insectivora), Donald W. Duszynski, William C. Marquardt

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Three of 6 female long-clawed shrews, Sorex unguiculatus Dobson, 1890, collected on the island of Hokkaido, Japan, were found to have unsporulated oocysts and sexual stages (both macro- and microgamonts) in varying stages of development of an unidentified coccidium in both lactating and non lactating mammary glands. Gamonts developed in the alveoli of the mammary glands, and oocysts were found in the lactiferous ducts and in pools of milk. Mature macrogamonts were 11.9 × 15.2 μm (10-14 × 14-20 μm), whereas completely developed microgamonts with many gametes were 14.8 × 16.8 μm (10-18 × 13-20 μm). Oocysts in tissue sections …

Eimeria Species From Cryptotis Shrews (Insectivora: Soricidae) With Description Of A New Species, Donald W. Duszynski, Ralph P. Eckerlin, Timothy J. Mccarthy

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Fresh fecal samples from 12 shrews, 10 Cryptotis goodwini Jackson, 1933, and 2 Cryptotis merriami Thomas, 1898, were collected between December 1994 and May 1998; 11 (92%) were positive for eimeriid coccidia, including 8 of 8 C. goodwini and 2 of 2 C. merriami from Honduras and 1 of 2 C. goodwini from Guatemala. Two Eimeria species were found: 1 is consistent with the description of Eimeria whitakeri Upton and McAllister, 1991, and 1 is described in this study as new. Sporulated oocysts of the new species are subspheroidal, 16.8 × 15.7 (14–20 × 15–19) μm, with a length–width (L/W) …

United States Department Of Agriculture–Agricultural Research Service Research On Veterinary Pests, Jerome Hogsette

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

An overview of ARS research in the field of veterinary pests is presented. Results of research from the past three years on ticks, fire ants, nuisance flies, mosquitoes, sand flies and black flies, among others, are included. Where applicable, significance of research is discussed.

Inactivation Of Feline Calicivirus And Adenovirus Type 40 By Uv Radiation, Jeanette A. Thurston-Enriquez, Charles N. Haas, Joseph Jacangelo, Kelley Riley, Charles P. Gerba

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Little information regarding the effectiveness of UV radiation on the inactivation of caliciviruses and enteric adenoviruses is available. Analysis of human calicivirus resistance to disinfectants is hampered by the lack of animal or cell culture methods that can determine the viruses’ infectivity. The inactivation kinetics of enteric adenovirus type 40 (AD40), coliphage MS-2, and feline calicivirus (FCV), closely related to the human caliciviruses based on nucleic acid organization and capsid architecture, were determined after exposure to low-pressure UV radiation in buffered demand-free (BDF) water at room temperature. In addition, UV disinfection experiments were also carried out in treated groundwater with …

Host Specificity Of The Leaf Beetle, Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae) From Asia, A Biological Control Agent For Saltcedars (Tamarix: Tamaricaceae) In The Western United States, C. Jack Deloach, Phil A. Lewis, John C. Herr, Raymond I. Carruthers, James L. Tracy, Joye Johnson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Four species of saltcedars, Tamarix ramosissima Ledeb., Tamarix chinensis Lour., Tamarix parviflora DC., and T. canariensis Willd. and their hybrids, are exotic, invasive small trees from Asia that cause great damage to riparian ecosystems of the western United States. They displace native plant communities, degrade wildlife habitat (including that of many endangered species), increase soil salinity and wildfires, lower water tables, reduce water available for agriculture and municipalities, and reduce recreational use of affected areas. Phytophagous insects are abundant on saltcedar in the Old World and we selected Diorhabda elongata Brullé deserticola Chen as the top candidate biological control agent …

Biology Of Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae), An Asian Leaf Beetle For Biological Control Of Saltcedars (Tamarix Spp.) In The United States, Phil A. Lewis, C. Jack Deloach, Allen E. Knutson, James L. Tracy, Thomas O. Robbins

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Adults and larvae of Diorhabda elongata Brullé subspecies deserticola Chen feed on the foliage of saltcedars (Tamarix spp.). All three instars are black, the 2nd with an indistinct, and the 3rd with a distinct yellowish lateral stripe; full-grown larvae reach ca. 9mm in length and pupate in cells in litter on the ground or a few cm below the soil surface. Adults are yellowish with two dark brown stripes on each elytron. Duration of the egg averaged 5 days, 1st instar 4.9 days, 2nd instar 4.8 days, 3rd instar 7.4 days, prepupa 4.8 days, and pupa 7.1 days at …

Large Summer Population Of Multicolored Asian Lady Beetle In North Dakota, Louis S. Hesler

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The multicolored Asian lady beetle (Harmonia axyridis), hereafter MALB, is a Palearctic species that established relatively recently in eastern (Chapin and Brou 1991) and western North America (Dreistadt et a1. 1995). Populations of MALB have expanded throughout eastern North America (McCorquodale 1998) and among western coastal states (LaMana and Miller 1996). MALB was discovered in North Dakota in September 2000 (Fauske et a1. 2003). It currently is known from seven counties in eastern and northern North Dakota, based on one to two specimens per county (Fauske et al. 2003). MALB also has been found in South Dakota and …

The Impact Of Raising And Exhibiting Selected 4-H Livestock Projects On The Development Of Life And Project Skills, Clinton P. Rusk, Jill M. Summerlot-Early, Krisanna L. Machtmes, B. Allen Talbert, Mark Balschweid

Department of Agricultural Leadership, Education, and Communication: Faculty Publications

The purpose of the study was to identify perceptions of Indiana 4-H livestock members enrolled in beef, sheep and swine projects regarding their ability to perform project skills and develop life skills. A questionnaire was mailed to a sample of 420 4-H beef, sheep, and swine members, with a response rate of 41.9%. Members were able to accomplish project skills in the areas of sportsmanship, safety, animal grooming, and animal selection. Respondents are not as confident in their abilities related to animal health care. Members who exhibited at the state fair have higher skill levels in the areas of animal …

Reduction Of High Soil Test Phosphorus By Corn And Soybean Varieties, Bahman Eghball, J.F. Shanahan, Gary E. Varvel, John Gilley

Department of Agronomy and Horticulture: Faculty Publications

Soils with high levels of P can contribute to excess P in runoff and subsequently pollute the surface water. Excess P in the soil can be removed from the system by harvesting crops. The objectives of this study were to evaluate corn (Zea mays L.) P removal effects on soil P reduction, and to evaluate various corn hybrids and soybean [Glycine max (L.) Merr.] varieties for differences in grain P concentration and P removal. Soil with varying P levels as a result of annual or biennial beef cattle (Bos taurus) feedlot manure or compost appli- enough …

Proceedings Of The European Conference Black Grouse – Endangered Species Of Europe (September 8–12, 2003: Prague, Czech Republic), Petra Málková, Petr Procházka

Galliformes Specialist Group and Affiliated Societies: Conference Proceedings

RSPB black grouse conservation work in north Scotland, Chris Donald and Dave O’Hara

Influences of habitat structure, climate, disturbances and predation on population dynamics of black grouse in the northern Ore Mountains, Sven Herzog and Torsten Krüger

Population fragmentation and genetic variability in European black grouse: A progress report, Jacob Höglund, David Baines, Jobs Karl Larsson, and Gernot Segelbacher

Black Grouse habitats in Poland, Robert Kamieniarz

Ecological requirements for black grouse: A case study in the Belgian Hautes-Fagnes, Christine Keulen, Yves Pieper, André Doyen, Olivier Charlet, Pascal Poncin, and Jean-Claude Ruwet

Climatic modelling of black grouse population dynamics: A game …