Digital Commons Network^™

Extraction Of Lipids From Grain Sorghum Ddg, L. Wang, Curtis L. Weller, K. T. Hwang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Soxhlet and recirculated solvent extraction methods were used to extract lipid materials from grain sorghum DDG. The lipid content in DDG with a moisture content of 6.7% (dry basis) was as high as 9.32% of the dried DDG as determined by Soxhlet extraction with n-hexane. There was a slight increase in the lipid yield from 9.21% to 9.68% when the moisture contents increased from 2.1% to 17.4% (d.b.). Thin-layer chromatography (TLC) analysis showed that the sorghum lipids were composed of triacylglycerols, fatty acids, fatty alcohols, fatty aldehydes, free sterols, wax esters, and steryl esters. A bench-scale recirculated extraction system was …

Geographic And Ontogenetic Variation In The Contact Calls Of The Kea, Alan B. Bond, Judy Diamond

Papers in Behavior in Biological Sciences

Regional and ontogenetic variation in the contact calls of the kea (Nestor notabilis), an omnivorous and socially complex New Zealand parrot, were examined throughout the range of the species. We recorded samples of kee-ah contact calls from sixteen resident adults and eleven juveniles and demonstrated significant differences between age classes in the acoustic form of the vocalization. Canonical correlation analysis revealed a gradient in the form of the kee-ah call in both adults and juveniles along and across the escarpment of the Southern Alps, the primary longitudinal mountain range on the South Island of New Zealand. Although the …

Regulation Of Enteric Endophytic Bacterial Colonization By Plant Defenses, A. Leonardo Iniguez, Yuemei Dong, Heather D. Carter, Brian M. M. Ahmer, Julie M. Stone, Eric W. Triplett

Department of Biochemistry: Faculty Publications

Bacterial endophytes reside within the interior of plants without causing disease or forming symbiotic structures. Some endophytes, such as Klebsiella pneumoniae 342 (Kp342), enhance plant growth and nutrition. Others, such as Salmonella enterica serovar Typhimurium (S. typhimurium), are human pathogens that contaminate raw produce. Several lines of evidence are presented here to support the hypothesis that plant defense response pathways regulate colonization by endophytic bacteria. An ethyleneinsensitive mutant of Medicago truncatula is hypercolonized by Kp342 compared to the parent genotype. Addition of ethylene, a signal molecule for induced systemic resistance in plants, decreased endophytic colonization in Medicago spp. …

Roles For Nutrients In Epigenetic Events, Anna M. Oommen, Jacob B. Griffin, Gautam Sarath, Janos Zempleni

Gautam Sarath Publications

The field of epigenetics is the study of modifications of DNA and DNA-binding proteins that alter the structure of chromatin without altering the nucleotide sequence of DNA; some of these modifications may be associated with heritable changes in gene function. Nutrients play essential roles in the following epigenetic events. First, folate participates in the generation of S-adenosylmethionine, which acts as a methyl donor in the methylation of cytosines in DNA; methylation of cytosines is associated with gene silencing. Second, covalent attachment of biotin to histones (DNA-binding proteins) plays a role in gene silencing and in the cellular response to DNA …

Indirect Interaction Between Two Native Thistles Mediated By An Invasive Exotic Floral Herbivore, F. Leland Russell, Svata M. Louda

School of Biological Sciences: Faculty Publications

Spatial and temporal variation in insect floral herbivory is common and often important. Yet, the determinants of such variation remain incompletely understood. Using 12 years of flowering data and 4 years of biweekly insect counts, we evaluated four hypotheses to explain variation in damage by the Eurasian flower head weevil, Rhinocyllus conicus, to the native North American wavyleaf thistle, Cirsium undulatum. The four factors hypothesized to influence weevil impact were variations in climate, weevil abundance, phenological synchrony, and number of flower heads available, either on wavyleaf thistle or on the other co-occurring, acquired native host plant (Platte thistle, Cirsium …

Abdominal Pigmentation Variation In Drosophila Polymorpha: Geographic Variation In The Trait, And Underlying Phylogeography, Jennifer A. Brisson, Daniela Cristina De Toni, Ian Duncan, Alan R. Templeton

School of Biological Sciences: Faculty Publications

Drosophila polymorpha is a widespread species that exhibits abdominal pigmentation variation throughout its range. To gain insight into this variation we combined phenotypic and genotypic data to test a series of nested hypotheses. First, we tested the null hypothesis that geographic variation in pigmentation is due to neutral factors. We used nested clade analysis to examine the distribution of haplotypes from a nuclear and a mitochrondrial locus. Restricted gene flow via isolation by distance, the primary inference of this phylogeographic analysis, was then used to generate and test the hypothesis of increasing average abdominal pigmentation difference with increasing geographic distance. …

Microsatellite Dna Analysis Shows That Greater Sage Grouse Leks Are Not Kin Groups, Robert M. Gibson, Debra Pires, Kathleen S. Delaney, Robert K. Wayne

School of Biological Sciences: Faculty Publications

The spectacular social courtship displays of lekking birds are thought to evolve via sexual selection, but this view does not easily explain the participation of many males that apparently fail to mate. One of several proposed solutions to this ‘lek skew paradox’ is that kin selection favors low-ranking males joining leks to increase the fitness of closely related breeders. We investigated the potential for kin selection to operate in leks of the greater sage grouse, Centrocercus urophasianus, by estimating relatedness between lekking males using microsatellite DNA markers. We also calibrated these estimates using data from known families. Mean relatedness within …

Linking Seed Fate To Natural Dispersal Patterns: Factors Affecting Predation And Scatter-Hoarding Of Virola Calophylla Seeds In Peru, Sabrina E. Russo

School of Biological Sciences: Faculty Publications

Natural seed deposition patterns and their effects on post-dispersal seed fate are critical in tropical tree recruitment. Previous research showed that the key dispersal agent of the neotropical tree, Virola calophylla, is the spider monkey (Ateles paniscus). Spider monkeys generate a heterogeneous seed deposition pattern because they scatter-disperse seeds diurnally, whereas they clump-disperse seeds at their sleeping sites. The recruitment consequences of this pattern were investigated using manipulative experiments and observations. Scatter-hoarding by spiny rats (Proechimys spp.) caused little rearrangement of the initial seed deposition pattern because they moved seeds only short distances. Seed survival to …

Terrestrial Behavior Of Ateles Spp., Christina J. Campbell, Filippo Aureli, Colin A. Chapman, Gabriel Ramos-Fernández, Kim Matthews, Sabrina E. Russo, Scott Suarez, Laura Vick

School of Biological Sciences: Faculty Publications

Spider monkeys (Ateles spp.) are well known for their highly arboreal lifestyle, spending much of their time in the highest levels of the canopy and rarely venturing to the ground. To investigate terrestriality by Ateles and to illuminate the conditions under which spider monkeys venture to the ground, we analyzed ad libitum data from 5 study sites, covering 2 species and 5 subspecies. Three of the sites are in Central/North America: Barro Colorado Island (BCI), Panama (Ateles geoffroyi panamensis), Santa Rosa National Park, Costa Rica (A. g. frontatus), and Punta Laguna, Mexico (A. g. yucatanensis). The 2 remaining sites are …

Soil-Related Performance Variation And Distributions Of Tree Species In A Bornean Rain Forest, Sabrina E. Russo, Stuart J. Davies, David A. King, Sylvester Tan

School of Biological Sciences: Faculty Publications

1. Spatial distributions of tropical trees often correlate with environmental variation, suggesting that ecological sorting caused by niche differentiation may be important for maintaining species diversity.

2. Four soil types have been identified in a 52-ha forest dynamics plot in Bornean mixed dipterocarp forest (ranked by increasing fertility and moisture: sandy loam, loam, fine loam, and clay). The distributions of 73% of tree species in the plot are significantly aggregated on one of these soil types. We tested the hypothesis that variation in performance (growth and mortality) underlies these edaphically biased species distributions.

3. Annual growth and mortality rates over …

Methylation Patterns Of Histone H3 Lys 4, Lys 9 And Lys 27 In Transcriptionally Active And Inactive Arabidopsis Genes And In Atx1 Mutants, Raul Alvarez-Venegas, Zoya Avramova

School of Biological Sciences: Faculty Publications

Covalent modifications of histone-tail amino acid residues communicate information via a specific ‘histone code’. Here, we report histone H3-tail lysine methylation profiles of several Arabidopsis genes in correlation with their transcriptional activity and the input of the epigenetic factor ARABIDOPSIS HOMOLOGOF TRITHORAX (ATX1) at ATX1-regulated loci. By chromatin immunoprecipitation (ChIP) assays, we compared modification patterns of a constitutively expressed housekeeping gene, of a tissue-specific gene, and among genes that differed in degrees of transcriptional activity. Our results suggest that the di-methylated isoform of histone H3-lysine4 (m²K4/H3) provide a general mark for gene-related sequences distinguishing them from non-transcribed …

Quantitative Trait Loci For Lipid Content In Drosophila Melanogaster, Mei-Hui Wang, Lawrence G. Harshman, Sergey V. Nuzhdin

Lawrence G. Harshman Publications

Recombinant inbred lines derived from a natural population were used to investigate natural genetic variation for lipid abundance, protein abundance, and weight of Drosophila melanogaster. Females were heavier and contained more lipid and soluble protein than males. Lipid and protein abundance were genetically correlated with female weight, but male weight was not correlated with lipid or protein. Lipid and protein abundance were genetically correlated in males but not in females. Quan-titative trait loci (QTLs) for weight and protein abundance were predominantly on the X chromo-some, whereas QTLs for lipid abundance were found on the second and third chromosomes. QTLs …

Complex Signal Function: Developing A Framework Of Testable Hypotheses, Eileen Hebets, Daniel R. Papaj

Eileen Hebets Publications

The basic building blocks of communication are signals, assembled in various sequences and combinations, and used in virtually all inter- and intra-specific interactions. While signal evolution has long been a focus of study, there has been a recent resurgence of interest and research in the complexity of animal displays. Much past research on signal evolution has focused on sensory specialists, or on single signals in isolation, but many animal displays involve complex signaling, or the combination of more than one signal or related component, often serially and overlapping, frequently across multiple sensory modalities. Here, we build a framework of functional …

Potential Roles Of Follicular Dendritic Cell–Associated Osteopontin In Lymphoid Follicle Pathology And Repair And In B Cell Regulation In Hiv-1 And Siv Infection, Qingsheng Li, Jeffrey D. Lifson, Lijie Duan, Timothy Schacker, Cavan Reilly, John V. Carlis, Jacob D. Estes, Ashley T. Haase

Qingsheng Li Publications

Osteopontin is a multifunctional protein with known roles in bone remodeling, wound healing, and normal and pathological immune responses. We showed in microarray studies that osteopontin gene expression is increased in human immunodeficiency virus type 1 (HIV-1)–infected lymphatic tissues after treatment, and we undertook mapping experiments to study osteopontin’s possible functions in this context. We discovered species-specific colocalization of osteopontin with the follicular dendritic cell (FDC) network in lymphatic tissues in HIV-1 and simian immunodeficiency virus infections, and we found that changes in FDC-associated osteopontin covary with changes in lymphoid follicles during acute and late stages of infection and in …

Using Molt Limits To Age Western Bluebirds, Daizaburo Shizuka, Janis L. Dickinson

Papers in Ornithology

Using data on the extent of prebasic molt in known-aged adult and first-winter Western Bluebirds (Sialia mexicana), we assessed the accuracy of the molt limit as a tool for ageing birds. Sixty-nine known-aged birds were examined over the winter 2002–2003 in upper Carmel Valley, California. We also examined 29 breeding males in spring 2004 to assess the accuracy of this method for ageing birds during the breeding season. All birds were aged correctly using molt limit as the defining characteristic. We found that all first-winter birds had replaced 2–8 greater secondary coverts, while adults had replaced all wing …

A New Species Of Skrjabingylus Petrov, 1927 (Nematoda: Metastrongyloidea) From The Frontal Sinuses Of The Hooded Skunk, Mephitis Macroura (Mustelidae), Ramon A. Carreno, Kathryn E. Reif, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Skrjabingylus santaceciliae n. sp. is described based on specimens from the frontal sinuses of a hooded skunk, Mephitis macroura, collected from the Area de Conservación Guanacaste, Costa Rica. Skrjabingylus santaceciliae n. sp. differs from the other 5 species in the genus in having pointed spicule tips that lack a rounded or lobed formation and by lacking a prominent distal projection at the tail tip. Morphometric comparisons show that S. santaceciliae n. sp. is much smaller than the only other valid species from Mephitis, Skrjabingylus chitwoodorum Hill, 1939. Likewise, morphometric comparisons also distinguish S. santaceciliae n. sp. from other described Skrjabingylus …

Phylogenetic Relationships Of Palaeacanthocephala (Acanthocephala) Inferred From Ssu And Lsu Rdna Gene Sequences, Martín García-Varela, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The Palaeacanthocephala is traditionally represented by 2 orders, Echinorhynchida and Polymorphida, with 10 and 3 families, respectively. To test the monophyly of the class, these 2 orders, and certain families, phylogenies were inferred using nuclear small-subunit (SSU) and large-subunit (LSU) ribosomal DNA sequences obtained for 29 species representing 10 families, 2 other classes of acanthocephalans, and 3 rotifer outgroups. Phylogenetic relationships were inferred by analyzing combined SSU and LSU sequences using maximum parsimony (MP) and maximum likelihood (ML) methods. Parsimony and ML trees inferred from combined analysis of these rDNA data strongly supported monophyly of Palaeacanthocephala and provided good resolution …

Coevolution And Biogeography Among Nematodirinae (Nematoda: Trichostrongylina) Lagomorpha And Artiodactyla (Mammalia): Exploring Determinants Of History And Structure For The Northern Fauna Across The Holarctic, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Nematodes of the subfamily Nematodirinae are characteristic components of a Holarctic fauna. the topology of a generic-level phylogenetic hypothesis, patterns of diversity, and geographic distributions for respective nematode taxa in conjunction with data for host occurrence are consistent with primary distributions determined across Beringia for species of Murielus, Rauschia, Nematodirus, and Nematodirella. Ancestral ghosts are represented by Lagomorpha, with evidence for a minimum of 1 host-switching-event and subsequent radiation in the Artiodactyla. Diversification may reflect vicariance of respective faunas along with episodic or cyclical range expansion and isolation across Beringia during the late Tertiary and Quaternary. Secondarily, species …

Pseudostertagia Bullosa (Nematoda: Trichostrongyloidea) In Artiodactyl Hosts From North America: Redescription And Comments On Systematics, Eric P. Hoberg, A. Abrams

Harold W. Manter Laboratory of Parasitology: Faculty Publications

A relationship for Pseudostertagia bullosa within the trichostrongyloids has been enigmatic or unresolved. Studies of the synlophe in males and females of P. bullosa revealed a tapering system anterior to the deirids and a pattern of parallel ridges extending to near the caudal extremity in both lateral and median fields. Structurally, the synlophe differs considerably from that seen among the Cooperiinae and exhibits homoplasy with respect to ridge systems among some Ostertagiinae. Other structural characters due to symplesiomorphy, homoplasy or because they represent autapomorphies do not serve to reveal the putative relationships for P. bullosa with other trichostrongyloids. Although somewhat …

Possible Recent Range Expansion Of Alcataenia Longicervica (Eucestoda: Dilepididae) Parasitic In Murres Uria Spp. (Alcidae) Into The North Atlantic [Short Communications], Sabir B. Muzaffar, Eric P. Hoberg, Ian L. Jones

Harold W. Manter Laboratory of Parasitology: Faculty Publications

A wide range of helminths has been recorded from murres Uria spp. (Threlfall 1971, reviewed by Hoberg 1984a, Muzaffar & Jones 2004). Of the cyclophyllidean cestodes that parasitize murres, the genus Alcataenia Spasskaya 1971 (Dilepididae) is represented by ten species, eight of which are restricted and specific to the auks; the other two species occur in gulls (Laridae). The intermediate hosts of Alcataenia are euphausiid crustaceans such as species of Thysanoessa (Shimazu 1975), which also form an important dietary component of breeding and wintering murres, particularly Thick-billed Murres Uria lomvia (Gaston & Noble 1985, Birkhead & Nettleship 1987, Elliot et …

Development And Pathogenesis Of Parelaphostrongylus Odocoilei (Nematoda: Protostrongylidae) In Experimentally Infected Thinhorn Sheep (Ovis Dalli), Emily J. Jenkins, Eric P. Hoberg, L. Polley

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Recently, the protostrongylid nematode Parelaphostrongylus odocoilei has been reported in a new host species, thinhorn sheep (Ovis dalli). For the first time, we completed the life cycle of P. odocoilei in three Stone’s sheep (O. dalli stonei) and two thinhorn hybrids (O. dalli stonei × O. dalli dalli), each infected with 200 third-stage larvae from slugs (Deroceras laeve). The prepatent period ranged from 68 days to 74 days, and shedding of first-stage larvae (L1) peaked at >10,000 L1 per gram of feces between 90 and 110 days postinfection. A total of 75, …

Holocene Paleoecology Along The Blekinge Coast, Southeast Sweden, And Implications For Climate And Sea-Level Changes, Shi-Yong Yu, Björn E. Berglund, Per Sandgren, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

To investigate the Holocene vegetation history and shoreline displacement along the southeastern Swedish coast, two radiocarbon dated pollen, macrofossil, and mineral magnetic sequences were studied in the western Blekinge coast: Hunnemara Lake and Smygen Bay. Both pollen records show mosaic vegetation with grasslands, heaths and woodlands prior to 11,300 cal. BP. Pinus-dominated mixed forest was initially established by 11,000 cal. BP. By 10,000 cal. BP, mixed forest with higher species diversity was fully established. Expansion of broad-leaved trees began at about 8,600 cal. BP, indicating the onset of the mid-Holocene thermal maximum in Scandinavia. Following the Ulmus decline ~5,800 …

Recent Records Of Formerly Extirpated Carnivores In Nebraska, Justin D. Hoffman, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

By the early 1900's, several large carnivores had been extirpated from Nebraska as a result of unrestricted hunting and trapping by early European settlers. Recently, there have been several confirmed records of carnivores that were once extirpated from Nebraska. In our study, we present new data for five species that recently were documented in Nebraska: Lynx canadensis, Ursus americanus, Canis lupus, Puma concolor, and Lontra canadensis. Restoration programs and legal protection afforded to these species in Nebraska and in adjacent states have allowed population numbers to increase. Because of the increase in populations of these …

Creating Computer Aided 3d Model Of Spleen And Kidney Based On Visible Human Project., Muhammet M. Aldur

Saudi Medical Journal

OBJECTIVES: To investigate the efficacy of computer aided 3-dimensional (3D) reconstruction technique on visualization and modeling of gross anatomical structures with an affordable methodology applied on the spleen and kidney. METHODS: From The Visible Human Project Dataset cryosection images, developed by the National Library of Medicine, the spleen and kidney sections were preferred to be used due to their highly distinct contours. The software used for the reconstruction were SurfDriver 3.5.3 for Mac and Cinema 4D XL version 7.1 for Mac OS X. This study was carried out in May 2004 at the Department of Anatomy, Hacettepe University, Ankara, Turkey. …

Biochemical Analysis Of Serum Pancreatic Amylase And Lipase Enzymes In Patients With Type 1 And Type 2 Diabetes Mellitus., Adib A. Aughsteen, Mustafa S. Abu-Umair, Sameer A. Mahmoud

Saudi Medical Journal

OBJECTIVES: To examine the pancreatic exocrine insufficiency in patient with diabetes mellitus by estimating serum pancreatic amylase and lipase enzymes in healthy subjects and in type 1 and type 2 diabetic patients. METHODS: The study was conducted on 20 normal healthy volunteers and 39 diabetic patients referred to Al-Isra Medical Laboratory, Amman, Jordan during the period from April - November 2003 after recording their age and gender. The age of onset of diabetes and the type of treatment were determined and the patients were categorized into type 1 and type 2 diabetics. Blood samples were collected and analyzed for fasting …

Information View Of Organization, Bob Travica

Journal of International Technology and Information Management

This article proposes an information view of organization that brings the information systems field closer to organization theory. Although voluminous bodies of literature have been developed within each of these disciplines and links between them do exist, their mutual informing is still insufficient. The proposed view of organization is intended to help convey results of information systems research to organizational scholars, while broadening theoretical horizons of the former. This article discusses the premises, conceptual framework, examples, and preliminary evidence of the information view of organization.

Effects Of A Prereading Intervention On The Literacy And Social Skills Of Children, J. Ron Nelson, Scott A. Stage, Michael H. Epstein, Corey D. Pierce

Department of Special Education and Communication Disorders: Faculty Publications

This study investigated the effects of an intensive prereading intervention on the beginning reading skills and social behavior of kindergarten children at risk for behavioral disorders and reading difficulties. Children identified through a systematic screening process were assigned randomly to experimental or nonspecific treatment conditions. Children who received the intensive prereading intervention showed statistically and educationally significant gains in their beginning reading skills relative to their counterparts in the nonspecific treatment condition. In contrast, improvements in teacher ratings of the classroom competence, emotional and behavioral self-control, and self-confidence of children in the experimental and nonspecific treatment conditions were not statistically …

Effects Of Endogenous Steroid Hormone Levels On Annual Survival In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown, Samrrah A. Raouf, Linda C. Smith, John C. Wingfield

School of Biological Sciences: Faculty Publications

The hormone corticosterone is an important part of animals’ response to environmental stress, modulating short-term adaptive changes in behavior and physiology. The hormone testosterone is also critical, especially for males, in regulating the expression of sexual behavior and parental care. These hormones can have costly consequences, however, and within populations individuals show variation in endogenous levels of both corticosterone and testosterone. We studied how annual survival varied as a function of natural levels of these hormones in colonially breeding Cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, USA, in 2000–2003. We sampled hormone levels of birds caught at colonies …

Testosterone And Group Size In Cliff Swallows: Testing The “Challenge Hypothesis” In A Colonial Bird, Linda C. Smith, Samrrah A. Raouf, Mary Bomberger Brown, John C. Wingfield, Charles R. Brown

School of Biological Sciences: Faculty Publications

The “challenge hypothesis” states that increases in testosterone levels of male animals during the breeding season are directly related to the extent of intrasexual competition for resources or mates that they experience. Although often tested in territorial species, the challenge hypothesis has not been evaluated for colonial animals that live in groups of different sizes and that thus experience different intensities of intrasexual competition. We measured circulating testosterone levels of male and female cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, where these birds nest in colonies of widely different sizes. Males had significantly higher testosterone levels than females, …

Global Warming Is Changing The Dynamics Of Arctic Host-Parasite Systems, S. J. Kutz, Eric P. Hoberg, L. Polley, E. J. Jenkins

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Global climate change is altering the ecology of infectious agents and driving the emergence of disease in people, domestic animals, and wildlife. We present a novel, empirically based, predictive model for the impact of climate warming on development rates and availability of an important parasitic nematode of muskoxen in the Canadian Arctic, a region that is particularly vulnerable to climate change. Using this model, we show that warming in the Arctic may have already radically altered the transmission dynamics of this parasite, escalating infection pressure for muskoxen, and that this trend is expected to continue. This work establishes a foundation …