Life Sciences Commons^™

Influence Of Swimming Speed On Metabolic Rates Of Juvenile Pacific Bluefin Tuna And Yellowfin Tuna, Jason M. Blank, Charles J. Farwell, Jeffery M. Morrissette, Robert J. Schallert, Barbara A. Block

Biological Sciences

Bluefin tuna are endothermic and have higher temperatures, heart rates, and cardiac outputs than tropical tuna. We hypothesized that the increased cardiovascular capacity to deliver oxygen in bluefin may be associated with the evolution of higher metabolic rates. This study measured the oxygen consumption of juvenile Pacific bluefin Thunnus orientalis and yellowfin tuna Thunnus albacares swimming in a swim-tunnel respirometer at 20°C. Oxygen consumption ( Mo₂) of bluefin (7.1–9.4 kg) ranged from 235 ± 38 mg kg^-1 h^-1 at 0.85 body length (BL) s^-1 to 498 ± 55 mg kg^-1 h^-1 at 1.80 …

A Novel Lux Operon In The Cryptically Bioluminescent Fish Pathogen Vibrio Salmonicida Is Associated With Virulence, Eric J. Nelson, Hege S. Tunsjø, Pat M. Fidopiastis, Henning Sørum, Edward G. Ruby

Biological Sciences

The cold-water-fish pathogen Vibrio salmonicida expresses a functional bacterial luciferase but produces insufficient levels of its aliphatic-aldehyde substrate to be detectably luminous in culture. Our goals were to (i) better explain this cryptic bioluminescence phenotype through molecular characterization of the lux operon and (ii) test whether the bioluminescence gene cluster is associated with virulence. Cloning and sequencing of the V. salmonicida lux operon revealed that homologs of all of the genes required for luminescence are present: luxAB (luciferase) and luxCDE (aliphatic-aldehyde synthesis). The arrangement and sequence of these structural lux genes are conserved compared to those in related species of …

Genome Size Evolution In Relation To Leaf Strategy And Metabolic Rates Revisited, Jeremy M. Beaulieu, Ilia J. Leitch, Charles A. Knight

Biological Sciences

• Background and AimsIt has been proposed that having too much DNA may carry physiological consequences for plants. The strong correlation between DNA content, cell size and cell division rate could lead to predictable morphological variation in plants, including a negative relationship with leaf mass per unit area (LMA). In addition, the possible increased demand for resources in species with high DNA content may have downstream effects on maximal metabolic efficiency, including decreased metabolic rates.

• MethodsTests were made for genome size-dependent variation in LMA and metabolic rates (mass-based photosynthetic rate and dark respiration rate) using our own …

Counterproductive Mix Of Science And Theology: Review Of Astronomy And The Bible - Questions And Answers By Donald B. Deyoung, William D. Stansfield

Biological Sciences

No abstract provided.

Availability Of Dissolved Organic Matter Offsets Metabolic Costs Of A Protracted Larval Period For Bugula Neritina (Bryozoa), Collin H. Johnson, Dean E. Wendt

Biological Sciences

For nearly a century researchers have investigated the uptake and utilization of dissolved organic matter (DOM) by marine invertebrates, but its contribution to their growth, reproduction, and survival remains unclear. Here, the benefit of DOM uptake was assessed for the marine bryozoan Bugula neritina (Linnaeus 1758) through performance comparisons of individuals in the presence and absence of DOM. The experiments were performed using B. neritina collected from floating docks in Beaufort, NC, USA from July to September 2004. Seawater was subjected to ultraviolet irradiation to reduce naturally occurring DOM, and then enriched with either 1 μM of palmitic acid or …

Discriminant Function Analysis In Marine Ecology: Some Oversights And Their Solutions, J. Wilson White, Benjamin I. Ruttenberg

Biological Sciences

Marine ecologists commonly use discriminant function analysis (DFA) to evaluate the similarity of distinct populations and to classify individuals of unknown origin to known populations. However, investigators using DFA must account for (1) the possibility of correct classification due to chance alone, and (2) the influence of prior probabilities of group membership on classification results. A search of the recent otolith chemistry literature showed that these two concerns are sometimes ignored, so we used simulated data sets to explore the potential pitfalls of such oversights. We found that when estimating reclassification success for a training data set, small sample sizes …

Isolation And Selective Culture Of Quail Primordial Germ Cells And The Development Of A Cross Culture System To Harbor Development Of Manipulated Embryos, C. M. Kimmell, A. Saribalis, J. Echeverria, L. Shuey, K. A. Shaw, K. L. Shaw, D. G. Peterson

Animal Science

Primordial germ cells (PGCs) are the embryonic precursors of adult egg and sperm. Isolation, propagation, genetic manipulation and reimplantation of modified PGCs that retain their commitment to the germline have been recently described for the successful generation of transgenic chickens [1]. Here, we report the adaptation and application of these techniques to Japanese quail for the purpose of future applications involving the introduction of a phytase transgene as previously described [2]. Quail PGCs are harvested by aspiration of whole embryonic blood from embryos that have been incubated for 48– 52 h. Blood is aspirated using a mouth pipette fitted with …

The Role Of Local And Regional Processes In Structuring Larval Dragonfly Distributions Across Habitat Gradients, S J. Mccauley

Biological Sciences

Despite the importance of community-structuring processes operating at both local and regional scales, there is relatively little work examining both forces within a single system. I used a combination of observational and experimental approaches to examine the processes structuring larval dragonfly distributions in lentic habitats that encompass a gradient of both permanence and top predator type. I compared the relative vulnerability of species to predators from different portions of this gradient to assess the role of predation as a local force structuring communities. I also assessed the role of regional processes on species’ distributions by examining species’ propensity to disperse …

Arbor Day Confusion, William D. Stansfield

Biological Sciences

No abstract provided.

The Long And Winding Road: Influences Of Intracellular Metabolite Diffusion On Cellular Organization And Metabolism In Skeletal Muscle, Stephen T. Kinsey, Kristin M. Hardy, Bruce R. Locke

Biological Sciences

A fundamental principle of physiology is that cells are small in order to minimize diffusion distances for O₂ and intracellular metabolites. In skeletal muscle, it has long been recognized that aerobic fibers that are used for steady state locomotion tend to be smaller than anaerobic fibers that are used for burst movements. This tendency reflects the interaction between diffusion distances and aerobic ATP turnover rates, since maximal intracellular diffusion distances are ultimately limited by fiber size. The effect of diffusion distance on O₂ flux in muscle has been the subject of quantitative analyses for a century, but the …

Lipid Binding Characterization Of Lactic Acid Bacteria In Dairy Products, D. Bachiero, Salvador Uson, Rafael Jiménez-Flores

Dairy Science

Abstract of paper presented at the 2007 Joint Annual Meeting of the American Dairy Science Association & the American Society of Animal Science.

Effects Of Refrigeration And Calcium On Whey Protein Aggregation, M. R. Costa, Guillaume Brisson, M. L. Gigante, Phillip S. Tong, Rafael Jiménez-Flores

Dairy Science

Abstract of paper presented at the 2007 Joint Annual Meeting of the American Dairy Science Association & the American Society of Animal Science.

Proximate Developmental Mediators Of Sexual Dimorphism In Size: Case Studies From Squamate Reptiles, Henry B. John‐Alder, Robert M. Cox, Emily N. Taylor

Biological Sciences

Sexual dimorphism in size (sexual size dimorphism; SSD) is nearly ubiquitous, but the relative importance of genetic versus environmental control of SSD is not known for most species. We investigated proximate determinants of SSD in several species of squamate reptiles, including three species of Sceloporus lizards and the diamond‐backed rattlesnake (Crotalus atrox). In natural populations of these species, SSD is caused by sexual differences in age‐specific growth. Males and females, however, may often share similar potentials for growth: growth is strongly responsive to the availability of food, and sexual differences in growth can be greatly suppressed or completely …

Nontarget Effects Of The Mosquito Adulticide Pyrethrin Applied Aerially During A West Nile Virus Outbreak In An Urban California Environment, Walter M. Boyce, Sharon P. Lawler, Jennifer M. Schultz, Shannon J. Mccauley, Lynn S. Kimsey, Michael K. Niemela, Carrie F. Nielsen, William K. Reisen

Biological Sciences

In August 2006, a pyrethrin insecticide synergized with piperonyl butoxide (EverGreen Crop Protection EC 60-6, McLaughlin Gormley King Company, Golden Valley, MN) was sprayed in ultralow volumes over the city of Davis, CA, by the Sacramento-Yolo Mosquito and Vector Control District to control mosquitoes transmitting West Nile virus. Concurrently, we evaluated the impact of the insecticide on nontarget arthropods by 1) comparing mortality of treatment and control groups of sentinel arthropods, and 2) measuring the diversity and abundance of dead arthropods found on treatment and control tarps placed on the ground. We found no effect of spraying on nontarget sentinel …

Flavor Partition And Fat Reduction In Cheese By Supercritical Fluid Extraction: Processing Variables, Jessica L. Yee, Hany Khalil, Rafael Jiménez-Flores

Dairy Science

Developing low-fat cheese with flavor to match that of full-fat cheese has been a challenge in the dairy industry. The objective of this investigation was to develop lower fat Cheddar and Parmesan grated cheese using supercritical fluid extraction (SFE) and characterize its flavor profile comparative to a full-fat product. Specifically, enabling flavor compound partition between the matrices of cheese and extracted lipids. Carbon dioxide (CO₂) was the supercritical fluid for fat extraction. Extraction took place in a 500 mL SFE vessel using 100 g of grated cheese. Fractional factorial design was utilized to investigate two levels of treatment …

Compartmentalization Of The Broad-Range Phospholipase C Activity To The Spreading Vacuole Is Critical For Listeria Monocytogenes Virulence, P.S. Marie Yeung, Yoojin Na, Amanda J. Kreuder, Helene Marquis

Biological Sciences

Listeria monocytogenes is a bacterial pathogen that multipliesin the cytosol of host cells and spreads directly from cellto cell by using an actin-based mechanism of motility. The broad-rangephospholipase C (PC-PLC) of L. monocytogenes contributes tobacterial escape from vacuoles formed upon cell-to-cell spread.PC-PLC is made as an inactive proenzyme whose activation requirescleavage of an N-terminal propeptide. During infection, PC-PLCis activated specifically in acidified vacuoles. To assess theimportance of compartmentalizing PC-PLC activity during infection,we created a mutant that makes constitutively active PC-PLC(the plcBpro mutant). Results from intracellular growth andcell-to-cell spread assays showed that the plcBpro mutant wassensitive to gentamicin, suggesting …

Correlated Evolution Of Genome Size And Seed Mass, Jeremy M. Beaulieu, Angela T. Moles, Ilia J. Leitch, Michael D. Bennett, John B. Dickie, Charles A. Knight

Biological Sciences

• Previous investigators have identified strong positive relationships between genome size and seed mass within species, and across species from the same genus and family. • Here, we make the first broad-scale quantification of this relationship, using data for 1222 species, from 139 families and 48 orders. We analyzed the relationship between genome size and seed mass using a statistical framework that included four different tests. • A quadratic relationship between genome size and seed mass appeared to be driven by the large genome/seed mass gymnosperms and the many small genome size/large seed mass angiosperms. Very small seeds were never …

Consequences Of A Genetic Bottleneck In California Condors: A Mitochondrial Dna Perspective, Mary S. Adams, Francis X. Villablanca

Biological Sciences

The California Condor (Gymnogyps californianus) has recently survived a severe population bottleneck. The entire population was reduced to 27 individuals in 1982. The number of genetic founders was even smaller. We obtained 482 base pairs of DNA sequence from the mitochondrial control region (CR) of all founder individuals that potentially represented unique maternal haplotypes. Four unique haplotypes were present in the genetic founders. One of these haplotypes is unique to Topatopa, a male brought into captivity in 1967, whose haplotype will not persist in the future population. Haplotype diversity (h) was reduced by 25% between the founder population …

Evaluation Of A Tissue Culture-Based Approach For Differentiating Between Virulent And Avirulent Vibrio Parahaemolyticus Strains Based On Cytotoxicity, P.S. Marie Yeung, Martin Wiedmann, Kathryn J. Boor

Biological Sciences

The ability of only a subset of Vibrio parahaemolyticus strains to cause human infection underscores the need for an analytical method that can effectively differentiate between pathogenic strains and those that do not cause disease. We tested the feasibility of a tissue culture-based assay to determine whether clinical isolates could be differentiated from nonclinical isolates based on relative isolate cytopathogenicity. To screen for cytotoxic capability, we measured relative extracellular lactate dehydrogenase as an indicator of host cell damage in five different mammalian cell lines in the presence of V. parahaemolyticus. Isolates originating from clinical sources exhibited 15.5 to 59.3% …

Dietary Patterns And Breast Cancer Risk In The Shanghai Breast Cancer Study, Xiaohui Cui, Qi Dai, Marilyn Tseng, Xiao-Ou Shu, Yu-Tang Gao, Wei Zheng

Kinesiology and Public Health

The association of breast cancer with dietary patterns such as a western diet has not been studied in Asian women. We examined this among Shanghai Breast Cancer Study participants. Cases were of ages 25 to 64 years, diagnosed 08/1996-03/ 1998, and identified through a rapid case ascertainment system supplemented by the Shanghai Cancer Registry. Controls, selected from the general population of urban Shanghai, were frequency matched to cases by 5-year age group. Participants provided information on diet, lifestyle, and reproductive factors. In principal component analysis among 1,556 controls, two patterns emerged. a ‘‘vegetable-soy’’ pattern (tofu, cauliflower, beans, bean sprouts, green …

Dietary Intake And Breast Density In High-Risk Women: A Cross-Sectional Study, Marilyn Tseng, Celia Byrne, Kathryn A. Evers, Mary B. Daly

Kinesiology and Public Health

Background Women with a family history of breast cancer may be at higher risk for breast cancer, but few previous studies evaluating diet and breast cancer have focused on such women. The objective of the present study was to determine whether diet, a modifiable risk factor, is related to breast density among women at high genetic risk for breast cancer. Methods Women with at least one first-degree or second-degree relative with breast cancer or ovarian cancer participating in the Fox Chase Cancer Center Family Risk Assessment Program completed health history and food frequency questionnaires and received standard screening mammograms. Cranial–caudal …

Spatial Variation In The Chemical Composition Of Natal Otholiths From A Reef Fish In The Galápagos Islands, Benjamin I. Ruttenberg, Robert R. Warner

Biological Sciences

Over the past decade, researchers have used variation in the chemical composition of fish otoliths (earstones) to address a number of ecological questions, such as stock assessment and assessing rates of movement of individuals among habitats or life-history stages. However, these methods have yet to be applied successfully to the study of larval connectivity, a major unanswered question in marine ecology. Accomplishing this task requires a reference collection of pre-pelagic natal otoliths and accurate measurement of the chemical signatures of otoliths cores of recruits. We analyzed the chemical composition of natal otoliths from near-term benthic eggs of a damselfish (Stegastes …

Influence Of Ph And Heat Treatment Of Whey On The Functional Properties Of Whey Protein Concentrates In Yoghurt, Isabelle Sodini, Jerry Mattas, Phillip S. Tong

Dairy Science

Our aim was to investigate how two conditions of whey processing, pH and heat treatment, affect the physical properties of stirred yoghurts fortified to 45 g protein kg⁻¹ with whey protein concentrates (WPC). Cheddar whey was heated at pH 6.4 or pH 5.8 at 72 °C for 15 s, eventually heated further at 82 or 88 °C for 78 s, ultrafiltered, and spray dried. Resulting WPC contained 38% protein; the denaturation level of the whey protein was 10–53%. There were significant (P

A Comparative Study Of The Fractionation Of Regular Buttermilk And Whey Buttermilk By Microfiltration, Pierre Morin, Yves Pouliot, Rafael Jiménez-Flores

Dairy Science

The use of a ceramic microfiltration (MF) membrane for the fractionation of buttermilk and whey buttermilk obtained from pilot scale churning of cream and whey cream from industrial sources has been studied. Whey buttermilk contained comparable amounts of phospholipids compared to regular buttermilk but its protein content was lower due to the absence of caseins. However, it was found that lipid content of whey cream did vary significantly between lots resulting in important variations in the fat content of whey buttermilk. A twofold MF concentration of regular buttermilk doubled its phospholipids content whereas that of whey buttermilk was increased by …

Improved Monitoring Of Habs Using Autonomous Underwater Vehicles (Auv), Ian C. Robbins, G. J. Kirkpatrick, Shelley M. Blackwell, J. Hillier, Charles A. Knight, Mark A. Moline

Biological Sciences

Blooms of toxic algae are increasing in magnitude and frequency around the globe, causing extensive economic and environmental impacts. On the west coast of Florida, blooms of the toxic dinoflagellate Karenia brevis (Davis) have been documented annually for the last 30 years causing respiratory irritation in humans, fish kills, and toxin bioaccumulation in shellfish beds. As a result, methods need to be established to monitor and predict bloom formation and transport to mitigate their harmful effects on the surrounding ecosystems and local communities. In the past, monitoring and mitigation efforts have relied on visual confirmation of water discoloration, fish kills, …

Girls’ Dairy Intake, Energy Intake, And Weight Status, Laura M. Fiorito, Alison K. Ventura, Diane C. Mitchell, Helen Smiciklas-Wright, Leann L. Birch

Kinesiology and Public Health

We explored the relationships among girls’ weight status, dairy servings, and total energy intake. The hypothesis that consuming dairy could reduce risk for overweight was evaluated by comparing energy intake and weight status of girls who met or consumed less than the recommended three servings of dairy per day. Participants included 172 11-year-old non-Hispanic white girls, assessed cross-sectionally. Intakes of dairy, calcium, and energy were measured using three 24-hour recalls. Body mass index and body fat measures from dual-energy x-ray absorptiometry were obtained. Because preliminary analyses suggested systematic underreporting of energy intake, the relationships among dairy servings and measures of …

The Lasthenia Californica Story: It Started With Flavonoids, Bruce A. Bohm, Nishanta Rajakaruna

Biological Sciences

Our laboratory's study of Lasthenia (Asteraceae) began with an examination of flavonoid profiles of all species of the genus. The finding of two distinct flavonoid races within the L. californica complex led us to investigate environmental factors that might have been responsible for selection of these particular forms. Data were gathered on soil chemistry, allozyme variation, breeding biology, the effect of water stress on plant growth, and ion uptake physiology. In conjunction with workers at other institutions, DNA studies were undertaken to determine evolutionary relationships between the two races. These studies led to the recognition that racial differences had arisen …

Environmental Rearing Conditions Produce Forebrain Differences In Wild Chinook Salmon Oncorhynchus Tshawytscha, R. L. Kihslinger, Sean C. Lema, G. A. Nevitt

Biological Sciences

Recent studies suggest that hatchery-reared fish can have smaller brain-to-body size ratios than wild fish. It is unclear, however, whether these differences are due to artificial selection or instead reflect differences in rearing environment during development. Here we explore how rearing conditions influence the development of two forebrain structures, the olfactory bulb and the telencephalon, in juvenile Chinook salmon (Oncorhynchus tshawytscha) spawned from wild-caught adults. First, we compared the sizes of the olfactory bulb and telencephalon between salmon reared in a wild stream vs. a conventional hatchery. We next compared the sizes of forebrain structures between fish reared …

Textbooks: Expectations Vs. Reality: The Dna Story, William D. Stansfield

Biological Sciences

No abstract provided.

The Effects Of Carotenoid And Food Availability On Resistance To A Naturally Occurring Parasite (Gyrodactylus Turnbulli) In Guppies (Poecilia Reticulata), Gita R. Kolluru, Gregory F. Grether, Sandra H. South, Eric Dunlop, Andrea Cardinali, Linda Liu, Andreah Carapiet

Biological Sciences

Dietary carotenoids have been shown to confer immunological benefits to some species of animals in which males also use these pigments to attract mates. Thus, the potential exists for an allocation trade-off between the sexual and immunological functions of carotenoids. Food availability may also influence immune system function. The present study examined the effects of carotenoid and food availability on the resistance of male guppies (Poecilia reticulata Peters) from four wild populations to the parasite Gyrodactylus turnbulli Harris. Intermediate levels of carotenoid ingestion resulted in the lowest parasite loads, which suggests that carotenoids strengthen parasite resistance at low levels …