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Assessment Of The Acoustic Properties Of Common Tissue-Mimicking Test Phantoms, Jacinta Browne, K. Ramnarine, A. Watson, P. Hoskins

Articles

Ultrasound (US) test phantoms incorporating tissue-mimicking materials (TMMs) play an important role in the quality control (QC) and performance testing of US equipment. Three commercially available TMMs (ZerdineTM from CIRS Inc.; condensed-milk-based gel from Gammex RMI; urethane-rubber-based from ATS Labs) and a noncommercial agar-based TMM, were investigated. Acoustic properties were measured over the frequency range 2.25 to 15 MHz at a range of ambient temperatures (10 to 35°C). The acoustic velocity of the TMMs remained relatively constant with increasing frequency. Only the agar-based TMM had a linear increase of attenuation with frequency, with the other materials exhibiting nonlinear responses to …

Improving The Mass Rearing Possibilities Of Serangium Montazerii Fürsch (Coleoptera: Coccinellidae) On Different Host Plants Of Bemisia Tabaci (Genn.) (Homoptera: Aleyrodidae), Gonca Vatansever, M. Rifat Ulusoy, Lerzan Bakircioğlu Erkiliç

Turkish Journal of Agriculture and Forestry

The objectives of this study were to identify suitable plant species for mass rearing and to determine some biological characteristics of the predator Serangium montazerii Fürsch (Coleoptera: Coccinellidae) used in the biological control of Dialeurodes citri (Ashmead) (Homoptera: Aleyrodidae). The development time, mortality rate, preoviposition, oviposition and postoviposition periods and fecundity of S. montazerii were studied on various host plants using Bemisia tabaci (Genn.) (Homoptera: Aleyrodidae). Two cotton (Çukurova-1518 and Deltapine) and two eggplant (Pala and Çukurova topağı) cultivars were used at 25 ºC and 65 ± 5% RH in growth chambers. Additionally, life tables were constructed from the data …

Abalone Cultivation In Thailand: A Case Study, Nattakan Tun, Perasut Pianpijit, Suksan Juhong, Channarong Rodkum, Janenuj Wongtavatchai

The Thai Journal of Veterinary Medicine

Abalone are high cost seafoods regarded as delicacy. The decline of world abalone fishery has initiated the development of cultured abalone production in some countries. Thailand possesses geographical areas which are suitable for abalone habitats and the commercial abalone farming is currently promoted by the government. Commercial fishery for abalone in Thailand are presently unfamiliarity of their biology. This report describes the basis biology of abalone, development of abalone culture in tropical regions; selection and management of broodstock, in tank spawning, rearing of larvae through grow-out culture of advanced juveniles, to meet the requirement of consumers' seafood standard.

Paleoclimate Estimates From The Late Cretaceous San Juan Basin Using Leaf Physiognomy., Frederick Vogt

Student Work

Physiognomy of fossil leaves collected from Late Cretaceous floodplain sediments in present-day northwestern New Mexico was used to estimate paleoclimate. Woody dicot species were collected from this area to determine the Mean Annual Temperature (MAT) and Mean Annual Precipitation (MAP) using both uni- and multi-variate methods. From the same stratigraphic level at the contact between the upper Fruitland and lower Kirtland Formations, 188 specimens from three sites representing twenty-five morphotypes were sampled. Specimens were plotted on a collection curve to ensure species numbers approached saturation during sampling. Leaf margin analysis, a technique that compares the percentage of entire margin to …

Trends. Terrorist Brains, Ibpp Editor

International Bulletin of Political Psychology

This Trends article discusses the construct of biological reductionism in the context of the case of Red Army Faction member Ulrike Meinhof. For the author, overly emphasizing the biological aspects of Ms. Meinhof’s case might obscure legitimate grievances, and ultimately, lead to more cases of violence associated with terrorism.

Simple, Compact Source For Low-Temperature Air Plasmas, D. P. Sheehan, J. Lawson, M. Sosa, Richard A. Long

Faculty Publications

A simple, compact source of low-temperature, spatially and temporally uniform air plasma using a Telsa induction coil driver is described. The low-power ionization discharge plasma is localized (2 cm X 0.5 cm X 0.1 cm) and essentially free of arc channels. A Teflon coated rolling cylindrical electrode and dielectric coated ground plate are essential to the source’s operation and allow flat test samples to be readily exposed to the plasma. The plasma is a copious source of ozone and nitrogen oxides. Its effects on various microbes are discussed.

Abstracts Of Papers, 80th Annual Meeting Of The Virginia Academy Of Science, May 22-24, 2002, Hampton University, Hampton, Virginia

Virginia Journal of Science

Abstracts of papers that were presented at the 80th annual meeting of the Virginia Academy of Science.

A Long Way From Home: Transatlantic Sea Star Migration, William Jaeckle, Paul Kehle

Scholarship

For a marine biologist strolling along the eastern coast of South America, finding some sea stars (popularly called starfish, and technically members of the class Asteroidea of the phylum Echinodermata) is not all that unusual. However, when closer inspection reveals the sea stars to be ones that are also found on the shores of the western coast of Africa, the marine biologist now faces an interesting question: How did these sea stars come to be so far from home?

Originally published in Consortiumand used with permission.

Biology 1053 Course Proposal, Curriculum Committee

Curriculum Committee Reports

No abstract provided.

Fast Filter-And-Refine Algorithms For Subsequence Selection, Beng-Chin Ooi, Hwee Hwa Pang, Hao Wang, Limsoon Wong, Cui Yu

Research Collection School Of Computing and Information Systems

Large sequence databases, such as protein, DNA and gene sequences in biology, are becoming increasingly common. An important operation on a sequence database is approximate subsequence matching, where all subsequences that are within some distance from a given query string are retrieved. This paper proposes a filter-and-refine algorithm that enables efficient approximate subsequence matching in large DNA sequence databases. It employs a bitmap indexing structure to condense and encode each data sequence into a shorter index sequence. During query processing, the bitmap index is used to filter out most of the irrelevant subsequences, and false positives are removed in the …

Ecological Conditions Of The Papillion Creek Watershed: Effects Of Adjacent Land-Use., Pamela D. Cox

Student Work

Stream conditions were assessed for past and present landscapes of the Papillion Creek Watershed of northwest Omaha, Nebraska based on historical records, present land-use surveys and field data collected in June 2000 using the Environmental Protection Agency’s Rapid Bioassessment Protocol modified to meet the needs of the study. Less than 0.4% of the historic tallgrass Prairie remains, with the present landscape mostly in agriculture (83%) or residential-commercial developments (16%). No significant differences (P ≤ 0.05) were found between ten habitat parameters measured for each of three land-used categories, cultivated, residential-commercial, and other. The overall impact of increased land-use on the …

Seasonal Niche Strategy Of The Bloom-Forming Dinoflagellate Heterocapsa Triquetra, R. W. Litaker, P. A. Tester, C. S. Duke, B. E. Kenney, James L. Pinckney, J. Ramus

Faculty Publications

Heterocapsa triquetra is one of the most common bloom-forming dinoflagellates found in estuaries and near shore regions around the world. This work examined the environmental factors associated with 3 separate wintertime H. triquetra blooms in the shallow tidally mixed Newport River estuary, North Carolina, USA. During 2 of the blooms in 1982 and 1983, the estuary was sampled from a fixed, single location every hour for 14 d. During the third study, the estuary was sampled at 9 fixed locations over its entire length each week from late December 1997 through March 1998. This time period included the formation and …

Mutagenesis Induced By The Tumor Microenvironment: Implications Of Increased Dna Damage And Diminished Dna Repair, Jianling Yuan

Yale Medicine Thesis Digital Library

Tumors are characterized by microenvironmental heterogeneity, with regions of hypoxia, low pH, and nutrient deprivation. It has been proposed that such conditions may be an important factor contributing to cancer genetic instability. Using a chromosomally based lambda phage shuttle vector as a mutation reporter, we show that growth of cells in hypoxia and/or at low pH results in elevated mutation frequencies in two different reporter genes. To elucidate the mechanism of the tumor microenvironment-induced genetic instability, we first measured the production of DNA damage upon hypoxia and re-oxygenation in culture. We found that under such conditions, the intracellular level of …

Estimating The Spatial Extent Of Bottom-Water Hypoxia And Habitat Degradation In A Shallow Estuary, Christopher P. Buzzelli, Richard A. Luettich Jr., Sean P. Powers, Charles H. Peterson, Jesse E. Mcninch, James L. Pinckney, Hans W. Paerl

Faculty Publications

Bottom-water hypoxia (≤ 2 mg 1^-1 dissolved oxygen [DO]) greatly modifies the benthic habitat of estuaries, depending upon spatial extent, duration, and frequency. Bottom-water hypoxia often develops under conditions of density stratification, which inhibits vertical mixing, and warm temperatures, which enhance biological oxygen demand. Long-term, mid-channel data from the Neuse River Estuary in North Carolina permitted evaluation of how stratification and temperature combined to affect DO concentrations at the bottom. Salinity stratification (DS) and water temperature (T) explained respectively 30 and 23% of the variance in bottom-water DO concentrations. The amount of salinity stratification required to induce bottom-water …

Iron, Folate And Vitamin B12 Status Of Apparently Healthy Irish Adult Women Attending General Practitioners In Inner-City Dublin, Helen R. Casey

Doctoral

There is substantial related morbidity and mortality among men and women in developed countries. Certain events during the course of a woman’s life such as menstruation, pregnancy, lactation and the menopause may compromise haematinic nutrient status. The purpose of this study was to investigate iron, folate and vitamin B12 status among a sample of apparently healthy, non-pregnant Irish adult women attending general practitioners in inner-city Dublin. Dietary, socio-economic, medical and lifestyle factors contributing to status of these haematinic nutrients were extensively examined. The initial part of the work validated the methods in a representative sample of inner city Dublin women …

Thin Laser Light Sheet Microscope For Microbial Oceanography, Eran Fuchs, Jules S. Jaffe, Richard A. Long, Farooq Azam

Faculty Publications

Despite a growing need, oceanographers are limited by existing technological constrains and are unable to observe aquatic microbes in their natural setting. In order to provide a simple and easy to implement solution for such studies, a new Thin Light Sheet Microscope (TLSM) has been developed. The TLSM utilizes a well-defined sheet of laser light, which has a narrow (23 micron) axial dimension over a 1 mm x 1 mm field of view. This light sheet is positioned precisely within the depth of field of the microscope’s objective lens. The technique thus utilizes conventional microscope optics but replaces the illumination …

Sheep Research Poster, Utah State University

Research

This is a photo of Utah State University student, Stephanie Eng presenting her research on parasites found in sheep for Posters on the Hill at the Utah state Capitol.

Ec02-177 Purple Loosestrife, Stevan Z. Knezevic

University of Nebraska-Lincoln Extension: Historical Materials

Purple loosestrife (Lythrum salicaria) is an introduced invasive weed that isover running thousands of acres of wetlands and waterways in the Midwest. Once purple loosestrife invades a wetland, natural habitat is lost and the productivity of native plant and animal communities is severely reduced. These losses in turn interfere with various levels of the ecosystem and area recreational activities such as fishing, boating and hunting, diminishing revenue from tourism and impairing the social and economic well being of local communities. A single control measure cannot provide long-term, sustainable control of this weed. An integrated approach, using a variety …

Ec02-176 Musk Thistle, Fred Roeth, Steven R. Melvin, Irvin L. Schleufer

University of Nebraska-Lincoln Extension: Historical Materials

Musk thistle (Carduus nutans L.) is an introduced invasive broadleaf weed native to Europe, North Africa, and Asia. In these areas it is a minor weed because natural enemies keep its population low. When the plant was introduced into North America, its natural enemies were left behind. Without these natural checks, the thistle is able to thrive and compete with native vegetation.

Musk thistles aggressively invade all lands in Nebraska. Typical cropland weed control methods are very effective against them; however, land with permanent cover (pasture, range, roadway ditches and wasteland) that is not tilled or treated with a …

Ec02-172 Plumeless Thistle, Kara L. Hilgenfeld, Alex Martin

University of Nebraska-Lincoln Extension: Historical Materials

Plumeless thistle (Carduus acanthoides L.) is one of seven noxious weeds in Nebraska. An introduced invasive broadleaf weed native to Europe and Asia, plumeless thistle currently infests about 65,000 acres in Nebraska. Infestations of plumeless thistle may reduce productivity of pastures and rangeland, where infestations tend to be the largest. Plumeless thistle competes with and suppresses growth of desirable species. Heavy infestations prevent livestock from grazing the area and lighter infestations prevent livestock from eating plants growing near the thistle. Estimates place the annual loss in Nebraska agricultural production due to plumeless thistle at $162,000. Although plumeless thistle is …

The Perfect Body: Biomedical Utopias, Hille Haker

Theology: Faculty Publications and Other Works

No abstract provided.

Ec02-173 Spotted And Diffuse Knapweed, Neil L. Heckman, Ryan M. Goss, Roch E. Gaussoin, Stevan Z. Knezevic, John L. Lindquist

University of Nebraska-Lincoln Extension: Historical Materials

Spotted knapweed (Centaure amaculosa Lam. = C. biebersteinii DC.) and diffuse knapweed (C.diffusa Lam.) are two of Nebraska’s seven noxious weeds. They are also noxious in at least 17 other states. These are closely related species that are well adapted to a variety of habitats including open forests, rangelands and pastures, Conservation Reserve Program lands, roadsides, and ditch banks. Centaurea is a large genus of over 400 species, 32 of which are common weeds of the United States and several of which [e.g., yellowstar thistle, C. solstitalis L, and Russian knapweed, C. repens L. =Acroptilon repens (L.) …

Assessing Ice Storm Damage To Hardwood Forest Canopies Using The Advanced Solid-State Array Spectroradiometer (Asas) And Landsat Tm Imagery, James Stuart Burnett

Doctoral Dissertations

A major ice storm in January 1998 damaged 17 million acres of forestland in the Northeastern United States and Quebec Province. In July 1998 the airborne multiangle hyperspectral sensor, Advanced Solid-State Array Spectroradiometer (ASAS), acquired imagery for nine ice damaged target areas in the White Mountain National Forest (WMNF). Ice damage was also measured in situ at 288 sample plots. Radiance values for nadir ASAS images were normalized and the blue shift of the red edge was represented as the radiance value at 714 nm (714nr). The 714nr for 210 sites in 3 damage classes differentiated severely damaged sites from …

Ompd But Not Ompc Is Involved In Adherence Of Salmonella Enterica Serovar Typhimurium To Human Cells, Bochiwe Hlezipi Hara-Kaonga

Doctoral Dissertations

Salmonella enterica serovar Typhimurium expresses three major outer membrane proteins: OmpC, OmpF, and OmpD. Conflicting reports exist regarding the role of OmpC and OmpD in the pathogenesis of this organism. This study investigated the role of OmpC and OmpD in adherence to human U937 macrophages and T84 intestinal epithelial cells. OmpC and ompD mutant strains were created by transposon mutagenesis utilizing P22-mediated transduction of Tn10 and Tn 5 insertions into wild-type strain 14028. Fluorescein-labeled wild-type and mutant bacteria were incubated with PKH26-labeled T84 cells at various bacteria-to-cell ratios for 1 h at 37 C. Single and dual fluorescence of samples …

Photoprotective Role Of Beta -Carotene And Antioxidant Enzymes: A Shield Against Ultraviolet Damage In Dunaliella Bardawil, Andrea Lynn Grossman-White

Doctoral Dissertations

Photosynthetic and antioxidant responses following exposure to an array of irradiances and frequencies were examined and contrasted in two species of the unicellular green alga Dunaliella. Species selection was based on the ability of Dunaliella bardawil (UTEX 2538) to accumulate massive quantities of inter-thylakoid beta-carotene during exposure to stress or high irradiances of photosynthetically active radiation (PAR: 400-700 nm) while Dunaliella salina (UTEX 200) lacks this ability. Cells were cultured in two irradiances (150 and 35 mumol photons ·m-2·s -1), and then exposed to high red (wavelengths > 590 nm) or blue light (390-540 nm; 150 mumol photons·m -2·s--1), ultraviolet-A (320-400 …

Community And Ecosystem Analysis Of Forests Recovering From Landslide Disturbance: White Mountain National Forest, New Hampshire, David M. Bryant

Doctoral Dissertations

Sites recovering from landslide disturbance offer many opportunities to study ecosystem processes under extreme conditions. Landslides reset the topographic, microclimatic, parent material and vegetation state factors of ecosystem development. Water, and nutrient resources following landslides are more heterogenously distributed. Soil structure and development is disrupted. Solar insolation and diurnal temperature fluctuation exceed that of the surrounding forest. Consequently, plant colonization and community succession differ from less severely disturbed sites such as timber harvest or agricultural afforestation.

Two chapters of this dissertation address the unique conditions of landslide ecosystem development. Chapter 2 compares historical data collected in 1956 on a chronosequence …

Comparative Anatomy And Evolution Of The Gastrotrich Muscular System, Richard Hochberg

Doctoral Dissertations

Gastrotrichs figure prominently in metazoan phylogeny because they share a suite of complex morphological characteristics with several other members of the Bilateria. But their microscopic size, cryptic interstitial habitat, and lack of fossil record have exacerbated the usual barriers to phylogenetic analysis. To arrive at a better understanding of gastrotrich systematics and evolution, cladistic analyses and detailed studies of the muscular system were performed.

A fluorescent F-actin stain was applied to whole mounts of 26 species of Gastrotricha to characterize the musculature. Muscle patterns were mapped, their functions inferred, and the direction of evolution hypothesized for several families. The musculature …

Expression, Activation, And Regulation Of Matrix Metalloproteinase 2 (Mmp-2) In The Bovine Corpus Luteum, Bo Zhang

Doctoral Dissertations

Matrix metalloproteinases (MMPs) have been postulated to be important for angiogenesis and for tissue remodeling events associated with corpus luteum (CL) development. The MMPs are mainly regulated at three levels, transcription, activation, and inhibition by endogenous tissue inhibitors of metalloproteinases (TIMPs). Unlike most MMPs, pro-MMP-2 activation is accomplished on the cell surface rather than extracellularly. The objectives of the present study were to clone bovine cDNAs for MMP-2 and its activator, membrane type 1- (MT 1-)MMP, to investigate the expression and localization of MMP-2, MT1-MMP, TIMP-1, and TIMP-2 in three ages of CL, and to explore the regulation of MMP-2 …

Birth, Death And Taxis: North Atlantic Right Whales In The Twenty-First Century, Scott Douglas Kraus

Doctoral Dissertations

Twenty two years of North Atlantic right whale data were analyzed. Several measures indicate reproduction in North Atlantic right whales is in a decline. Calving intervals have increased from about 3.3 years in the 1980's to over 5 years, and the age of first parturition is estimated to be 11 years. Females may lose calves before they are detected, artificially increasing the apparent age of first parturition and possibly affecting estimates of calving interval. Northern feeding habitat use patterns do not appear to affect reproduction.

Right whale mortality data was analyzed by age, sex, and habitat use patterns. A total …

Genetic Basis Of Adaptive Radiation In East African Cichlids, Richard Craig Albertson

Doctoral Dissertations

East African cichlids are a paramount example of adaptive morphological radiation. The most dramatic difference among species occurs in oral jaw design and correlates with ecological niche partitioning. Convergent evolution of trophic forms between lakes suggests a common mechanism. What combination of intrinsic and extrinsic factors constitute this mechanism still remains to be seen. The goal of this dissertation was to examine the genetic basis of shape differences between two closely related cichlid species that employ alternate modes of feeding. This was achieved through a number of independent experiments. First, I used field data to characterize the way in which …