Life Sciences Commons^™

Fossil Tuna Vertebrae Punctured By Istiophorid Billfishes, Vincent P. Schneider, Harry L. Fierstine

Biological Sciences

No abstract provided.

Foot Cooling Reduces Exercise-Induced Hyperthermia In Men With Spinal Cord Injury, Todd A. Hagobian, Kevin A. Jacobs, B Jenny Kiratli, Anne L. Friedlander

Kinesiology and Public Health

The number of individuals with spinal cord injury (SCI) participating in sports at recreational and elite levels is on the rise. However, loss of autonomic nervous system function below the lesion can compromise thermoregulatory capacity and increase the risk of heat stress relative to able-bodied (AB) individuals.
Purpose: To test the hypotheses that exercise in a heated environment would increase tympanic temperature (TTY) more in individuals with SCI than AB individuals, and that foot cooling using a new device would attenuate the rise in TTY during exercise in both groups.
Methods: Six subjects with SCI (lesions C5–T5) and six AB …

Bacterial Succession In A Petroleum Land Treatment Unit, Christopher W. Kaplan, Christopher L. Kitts

Biological Sciences

Bacterial community dynamics were investigated in a land treatment unit (LTU) established at a site contaminated with highly weathered petroleum hydrocarbons in the C(10) to C(32) range. The treatment plot, 3,000 cubic yards of soil, was supplemented with nutrients and monitored weekly for total petroleum hydrocarbons (TPH), soil water content, nutrient levels, and aerobic heterotrophic bacterial counts. Weekly soil samples were analyzed with 16S rRNA gene terminal restriction fragment (TRF) analysis to monitor bacterial community structure and dynamics during bioremediation. TPH degradation was rapid during the first 3 weeks and slowed for the remainder of the 24-week project. A sharp …

In Situ Cardiac Performance Of Pacific Bluefin Tuna Hearts In Response To Acute Temperature Change, Jason M. Blank, Jeffery M. Morrissette, Ana M. Landeira-Fernandez, Susanna B. Blackwell, Thomas D. Williams, Barbara A. Block

Biological Sciences

This study reports the cardiovascular physiology of the Pacific bluefin tuna (Thunnus orientalis) in an in situ heart preparation. The performance of the Pacific bluefin tuna heart was examined at temperatures from 30°C down to 2°C. Heart rates ranged from 156 beats min^–1 at 30°C to 13 beats min^–1 at 2°C. Maximal stroke volumes were 1.1 ml kg^–1 at 25°C and 1.3 ml kg^–1 at 2°C. Maximal cardiac outputs were 18.1 ml kg^–1 min^–1 at 2°C and 106 ml kg^–1 min^–1 at 25°C. These data indicate that cardiovascular function in …

Variation In Vasotocin Immunoreactivity In The Brain Of Recently Isolated Populations Of A Death Valley Pupfish, Cyprinodon Nevadensis, Sean C. Lema, Gabrielle A. Nevitt

Biological Sciences

Pupfishes in the Death Valley region of California and Nevada comprise a monophyletic group of populations that became isolated in remote streams and springs over the past 20,000 years. These aquatic habitats show considerable ecological diversity, and allopatric populations have evolved differences in morphology and behavior. Here we investigated whether the divergence of pupfish populations in Death Valley might be associated with changes in arginine vasotocin (AVT). We used immunocytochemistry to compare the expression of AVT in the brain of Amargosa pupfish (Cyprinodon nevadensis) from two Death Valley populations: (1) the Amargosa River—a highly variable desert stream containing …

Exercise And The Elderly: Guidelines And Practical Prescription Applications For The Clinician, Ann Y. Mcdermott, Heather Mernitz

Kinesiology and Public Health

Objective: To review the components of exercise prescription and approaches to developing an exercise prescription for older persons. Methods: Case studies and qualitative review of the literature. Results: Effective exercise programs specify the appropriate mode, intensity, duration, frequency, and progression of training. According to the American College of Sports Medicine, patients should participate in aerobic exercise 3 to 5 days per week, maintaining target heart rate for 20 to 60 minutes. Resistance training should be performed at least twice per week and should target the 7 major muscle groups. Proper technique is necessary and speed and breathing should be controlled. …

Exercise And The Elderly: A Scientific Rationale For Exercise Prescription, Heather Mernitz, Ann Y. Mcdermott

Kinesiology and Public Health

Objective: To review the benefits of exercise intervention in older persons and the role of exercise in the prevention and treatment of chronic disease. Methods: Qualitative assessment of the literature focusing on randomized controlled trials. Results: Participation in regular physical activity, including aerobic exercise and strength training, can improve health, functional ability, and quality of life in older persons. Higher levels of aerobic activity are associated with increased physical fitness, decreased total mortality, and improvements in cardiovascular risk profile. Resistance training combats myopathy and osteopenia and increases muscle endurance and function. Additional benefits from exercise include improved bone health and …

Promoting Long-Term Weight Control: Does Dieting Consistency Matter?, Amy A. Gorin, Suzanne Phelan, Rena R. Wing, James O. Hill

Kinesiology and Public Health

OBJECTIVE: The present study examined whether long-term weight loss maintenance is enhanced by maintaining the same diet regimen across the week and year or by dieting more strictly on weekdays and nonholiday periods than at other times.
METHOD: National Weight Control Registry participants (N¼1429) indicated on an eight-point scale whether they dieted more strictly on weekends than weekdays, adhered to the same diet regimen throughout the week, or dieted more strictly on weekdays. Participants responded to a similar question about holiday and vacation eating. Participants were then followed prospectively to determine whether scores on these questions were related to self-reported …

Promoting More Modest Weight Losses: A Pilot Study, Gary D. Foster, Suzanne Phelan, Thomas A. Wadden, Debra Gill, Jenna Ermold, Elizabeth Didie

Kinesiology and Public Health

Objective: This pilot study assessed the short- and long-term effects of a modified cognitive behavioral treatment designed to facilitate obese patients' acceptance of a 5% to 10% reduction in initial weight.
Research Methods and Procedures: Participants were 17 women with a mean age of 46.5 ± 9.7 years and BMI of 34.7 ± 2.9 kg/m². They participated in a 40-week program that included four phases. The first discussed the benefits of modest weight losses and the potential adverse effects of unrealistic expectations. Phase II provided instruction in traditional cognitive behavioral methods of weight control Phase III focused on …

A Comparison Between Point- And Semi-Continuous Sampling For Assessing Body Temperature In A Free-Ranging Ectotherm, Emily N. Taylor, Dale F. Denardo, Michael A. Malawy

Biological Sciences

We used intracoelomically implanted temperature dataloggers to obtain semi-continuous body temperature data and establish monthly thermal profiles for free-ranging rattlesnakes. We mimicked random and non-random point-sampling methods by selecting a single daily data point from all values or from restricted times of day to reflect common point-sampling constraints. Thermal profiles generated from point-sampling differed from those generated from semi-continuous sampling, and this difference was more apparent when point-sampling was non-random. We conclude that semi-continuous sampling provides a better estimate of thermal profiles, and that point-sampling methods are highly sensitive to deviations from true randomness.

Hamlet Revisited: How Evolution Really Works, William D. Stansfield

Biological Sciences

Delves into the artificial programs that are merely metaphors for the processes of organic evolution. Relation of this organic evolution with the phrases in the play "Hamlet" of Shakespeare; Disadvantage of using these metaphors as educational tools; Definition of various kinds of patterns for evolution.

Physical Forcing Of Phytoplankton Community Structure And Primary Production In Continental Shelf Waters Of The Western Antarctic Peninsula, Barbara B. Prezelin, Eileen E. Hofmann, Mark A. Moline, John M. Klinck

Biological Sciences

Analyses of a multidisciplinary data set, collected in continental shelf waters of the Western Antarctic Peninsula (WAP) during austral summer of January 1993, identified a previously unrecognized forcing mechanism that sets up a physical and chemical structure that supports and assures site-specific diatom-dominated communities and enhanced biological production (Prézelin et al., 2000). This forcing is active when the southern boundary of the Antarctic Circumpolar Current (ACC) flows along the shelf edge, thereby facilitating onshelf bottom intrusions of nutrient-rich Upper Circumpolar Deep Water (UCDW), which then is upwelled or mixed into the upper water column. At times or locations where UCDW …

New Taxa And New Combinations In North American Cirsium (Asteraceae: Cardueae), David J. Keil

Biological Sciences

Six new varieties are proposed in North American Cirsium (Asteraceae: Cardueae): C. arizonicum (A. Gray) Petrak var. tenuisectum D.J. Keil var. nov., C. eatonii (A. Gray) B.L. Rob. var. viperinum D.J. Keil, var. nov., C. edule Nutt. var. wenatchense D.J. Keil, var. nov., C. occidentale (Nutt.) Jeps. var. lucianum D.J. Keil, var. nov., C. scariosum Nutt. var. robustum D.J. Keil, var. nov., C. scariosum Nutt. var. toiyabense D.J. Keil, var. nov. Additionally, twenty new combinations are presented: C. arizonicum (A. Gray) Petrak var. bipinnatum (Eastw.) D.J. Keil, comb. nov., C. arizonicum (A. Gray) Petrak var. chellyense (R.J. Moore & Frankton) …

Biogeochemical Impact Of Summertime Coastal Upwelling On The New Jersey Shelf, Scott Glenn, Robert Arnone, Trisha Bergmann, Paul W. Bissett, Michael Crowley, Jay Cullen, Joe Gryzmski, Dale Haidvogel, Josh Kohut, Mark A. Moline, Mathew Oliver, Cris Orrico, Robert Sherrell, Tony Song, Alan Weidemann, Robert Chant, Oscar Schofield

Biological Sciences

The alternative hypothesis that observed regions of recurrent hypoxia on the New Jersey inner shelf are more related to coastal upwelling than riverine inputs of nutrients was investigated through a series of multidisciplinary research programs beginning in 1993. The largest variations in ocean temperatures along the New Jersey coast, other than seasonal, are found to be caused by episodic summertime upwelling events driven by southwesterly winds associated with the atmospheric Bermuda High. Off the southern coast of New Jersey, topographic variations associated with ancient river deltas cause upwelled water to evolve into an alongshore line of recurrent upwelling centers that …

Seasonal Steroid Hormone Levels And Their Relation To Reproduction In The Western Diamond-Backed Rattlesnake, Crotalus Atrox (Serpentes: Viperidae), Emily N. Taylor, Dale F. Denardo, David H. Jennings

Biological Sciences

We report seasonal variation in steroid hormone levels in blood samples from free-ranging Western Diamond-backed Rattlesnakes (Crotalus atrox), and the relationship between these hormones and events in the reproductive cycle. At a field site in the Sonoran Desert of south-central Arizona, we collected monthly blood samples over the course of two active seasons from 17 radiotelemetered females, and over three active seasons from 103 randomly encountered males. We used radioimmunoassay to measure plasma levels of 17β-estradiol, progesterone, corticosterone, and testosterone in samples from females, and corticosterone and testosterone in samples from males. Non-reproductive females have consistently low levels …

Bioinformatic Approaches For Objective Detection Of Water Masses On Continental Shelves, Mark A. Moline, Matthew J. Oliver, Scott Glenn, Josh T. Kohut, Andrew J. Irwin, Oscar M. Schofield, Paul W. Bissett

Biological Sciences

As part of the 2001 Hyper Spectral Coupled Ocean Dynamics Experiment, sea surface temperature and ocean color satellite imagery were collected for the continental shelf of the Mid-Atlantic Bight. These images were used to develop a water mass analysis and classification scheme that objectively describes the locations of water masses and their boundary locations. This technique combines multivariate cluster analysis with a newly developed genetic expression algorithm to objectively determine the number of water types in the region on the basis of ocean color and sea surface temperature measurements. Then, through boundary analysis of the water types identified, the boundaries …

Sex–Specific Effects Of Carotenoid Intake On The Immunological Response To Allografts In Guppies (Poecilia Reticulata), Gregory F. Grether, Shinji Kasahara, Gita R. Kolluru, Edwin L. Cooper

Biological Sciences

Rarely are the evolutionary origins of mate preferences known, but, recently, the preference of female guppies (Poecilia reticulata) for males with carotenoid‐based sexual coloration has been linked to a sensory bias that may have originally evolved for detecting carotenoid‐rich fruits. If carotenoids enhance the immune systems of these fishes, as has been suggested for other species, this could explain the origin of the attraction to orange fruits as well as the maintenance of the female preference for orange males. We used the classic immunological technique of tissue grafting to assay a component of the immune response of guppies …

Individual Colour Patches As Multicomponent Signals, Gregory F. Grether, Gita R. Kolluru, Karen Nersissian

Biological Sciences

Colour patches are complex traits, the components of which may evolve independently through a variety of mechanisms. Although usually treated as simple, two-dimensional characters and classified as either structural or pigmentary, in reality colour patches are complicated, three-dimensional structures that often contain multiple pigment types and structural features. The basic dermal chromatophore unit of fishes, reptiles and amphibians consists of three contiguous cell layers. Xanthophores and erythrophores in the outermost layer contain carotenoid and pteridine pigments that absorb short-wave light; iridophores in the middle layer contain crystalline platelets that reflect light back through the xanthophores; and melanophores in the basal …

Serpentine: A Model Habitat For Botanical Research In Sri Lanka, Nishanta Rajakaruna, Alan J. M. Baker

Biological Sciences

Serpentine (ultramafic) outcrops are found in most parts of the world and for many years have attracted the attention of soil scientists and plant biologists alike due to the unusual nature of both the substrate and the life forms they harbour. In this paper, we introduce serpentine outcrops as a model habitat for botanical studies and review preliminary findings of a recently conducted soil and floristic survey of four of the five known serpentine outcrops in Sri Lanka. We hope that this paper will stimulate much-needed studies, both exploratory and experimental, and point to the immediate need for conservation of …

Epidemiology, Pathogenesis, And Prevention Of Foodbome Vibrio Parahaemolyticus Infections, P.S. Marie Yeung, Kathryn J. Boor

Biological Sciences

Since its discovery about 50 years ago, Vibrio parahaemolyticus has been implicated as a major cause of foodborne illness around the globe. V. parahaemolyticus is a natural inhabitant of marine waters. Human infections are most commonly associated with the consumption of raw, undercooked or contaminated shellfish. A few individual V. parahaemolyticus virulence factors, including the thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH), have been investigated in depth, yet a comprehensive understanding of this organism's ability to cause disease remains unclear. Since 1996, serotype 03:K6 strains have been associated with an increased incidence of gastroenteritis in India and in Southeast …

Effects Of Acid Stress On Vibrio Parahaemolyticus Survival And Cytotoxicity, P.S. Marie Yeung, Kathryn J. Boor

Biological Sciences

For several foodbome bacterial pathogens, an acid tolerance response appears to be an important strategy for counteracting acid stress imposed either during food processing or by the human host. The acid tolerance response enhances bacterial survival of lethal acid challenge following prior exposure to sublethal acidic conditions. Previous studies have revealed relationships between a foodbome pathogen's ability to survive acid challenge and its infectious dose. Vibrio parahaemolyticus is capable of causing gastroenteritis when sufficient cells of pathogenic strains are consumed. This study was designed to characterize acid sensitivities and to compare the effect of sublethal acid exposure (adaptation) on survival …

Development Of A Multi-Disciplinary Ecological Model For Childhood Obesity, David W. Hey

Kinesiology and Public Health

During the past two decades the prevalence of childhood obesity has steadily increased in the United States. An ecological model of health behavior change has been recommended to address the rise in childhood obesity. The purpose of this study was to build a comprehensive, multi-disciplinary, ecological childhood obesity model by examining past theory and research in 25 journals covering five disciplines over a decade (1993-2002).

To identify environmental antecedents, this study collapsed 10 existing ecological models of obesity prevention and divided resultant antecedents (n=94) into five ecological categories (social norms/national policies, community factors, school factors, family/peer or interpersonal …

Dietary Patterns And Prostate Cancer Risk In The National Health And Nutrition Examination Survey Epidemiological Follow-Up Study Cohort, Marilyn Tseng, Rosalind A. Breslow, Robert F. Devillis, Regina G. Ziegler

Kinesiology and Public Health

Ecological studies implicate a “Western” diet in prostate cancer development, but whether dietary patterns measured in individuals are associated with risk has not been studied previously. We examined this issue using prospective data from the nationally representative United States Health Examination Epidemiological Follow-up Study. Among 3,779 men followed from 1982– 84 to 1992, 136 incident cases were identified. Using principal component analysis on responses to a 105-item dietary questionnaire, the following three distinct patterns were identified: a vegetable-fruit pattern; a red meat-starch pattern characterized by red meats, potatoes, cheese, salty snacks, and desserts; and a Southern pattern characterized by such …

The Edaphic Factor In The Origin Of Plant Species, Nishanta Rajakaruna

Biological Sciences

Although speciation has been a central focus in evolutionary biology for more than a century, there are very few case studies where we have a good understanding of the exact forces that may have acted in the diversification of a group of organisms. In order to examine such forces, botanists have often focused on closely related plants that are found under contrasting soil conditions. The study of such edaphically differentiated plants has provided valuable insight to the role of natural selection in evolution. This paper discusses several key studies that have appeared in the literature in the last half century …

Heat-Shock Protein 70 (Hsp70) As A Biochemical Stress Indicator: An Experimental Field Test In Two Congeneric Intertidal Gastropods (Genus: Tegula), Lars Tomanek, Eric Sanford

Biological Sciences

Although previous studies have demonstrated that heat-shock protein 70 (Hsp70) can be induced by environmental stress, little is known about natural variation in this response over short time scales. We examined how Hsp70 levels varied over days to weeks in two intertidal snail species of the genus Tegula. Sampling was conducted both under naturally changing environmental conditions and in different vertical zones on a rocky shore. The subtidal to low-intertidal T. brunnea was transplanted into shaded and unshaded mid-intertidal cages to assess temporal variation in Hsps under conditions of increased stress. For comparison, the low to mid-intertidal ,T. …

Continuous Hyperspectral Absorption Measurements Of Colored Dissolved Organic Material In Aquatic Systems, Gary J. Kirkpatrick, Cristina Orrico, Mark A. Moline, Matthew Oliver, Oscar M. Schofield

Biological Sciences

The majority of organic carbon in the oceans is present as dissolved organic matter (DOM); therefore understanding the distribution and dynamics of DOM is central to understanding global carbon cycles. Describing the time-space variability in colored dissolved organic matter (CDOM) has been difficult, as standard spectrophotometric methods for CDOM determination are laborious and susceptible to methodological biases. Previously, measurements of CDOM absorption in discrete water samples by use of a liquid-waveguide capillary cell (LWCC) compared favorably with measurements made with a benchtop spectrophotometer. Given this, we focused on automating the LWCC technique to improve our spatial and temporal sampling capabilities …

Analysis Of Platelet Activating Factor In The Gravid Reproductive Tracts Of Swine, William E. Plummer

Animal Science

Depressed hog prices in 1998 and 1999 were due to not enough shackle space (kill capacity) and not to a glut of slaughter swine. However, many swine producers were put out of business in California. In 2000, market prices rebounded due to increased shackle space and reduced numbers of slaughter swine available as a result of the sellouts of the previous two years. The economic roller coaster ride emphasized the need for maximizing profit while streamlining operations. Increasing numbers of pigs per litter, and thereby reducing the cost per pig produced, is one aspect of streamlining. A significant step in …

Complex Co-Substrate Addition Increases Initial Petroleum Degradation Rates During Land Treatment By Altering Bacterial Community Physiology, Christopher W, Kaplan, Brian G. Clement, Alice Hamrick, Robert W. Pease, Carl Flint, Raul J. Cano, Christopher L. Kits

Biological Sciences

A pilot-scale land treatment unit (LTU) was constructed at the former Guadalupe oil production field with the purpose of investigating the effect of co-substrate addition on the bacterial community and the resulting rate and extent of total petroleum hydrocarbon (TPH) degradation. The TPH was a weathered mid-cut distillate (C10-C32) excavated from the subsurface and stockpiled before treatment. A control cell (Cell 1) in the LTU was amended with nitrogen and phosphorus while the experimental cell (Cell 2) was amended with additional complex co-substrate—corn steep liquor. During the pilot LTU operation, measurements were taken of TPH, nutrients, moisture, aerobic heterotrophic bacteria …

Chromosome-Wide Control Of Meiotic Crossing Over In C. Elegans, Kenneth J. Hillers, Anne M. Villeneuve

Biological Sciences

A central event in sexual reproduction is the reduction in chromosome number that occurs at the meiosis I division. Most eukaryotes rely on crossing over between homologs, and the resulting chiasmata, to direct meiosis I chromosome segregation, yet make very few crossovers per chromosome pair [1] and [2]. This indicates that meiotic recombination must be tightly regulated to ensure that each chromosome pair enjoys the crossover necessary to ensure correct segregation. Here, we investigate control of meiotic crossing over in Caenorhabditis elegans, which averages only one crossover per chromosome pair per meiosis [3] and [4], by constructing genetic maps …

Characterization Of Six Polymorphic Microsatellites For The Polychaete Tubeworm Hydroides Elegans And Cross-Species Amplification In The Congener Hydroides Hexagonus, J. B. Pettengill, M. G. Hadfield, M. D. Schug, D. E. Wendt

Biological Sciences

We isolated and characterized six polymorphic microsatellite loci for the polychaete tubeworm, Hydroides elegans. Two additional loci were not reliably scorable and estimates of heterozygosity were obtained for the other six. In addition, cross-species amplification was successful for two loci using the congener H. hexagonus. Given that few microsatellite loci are available for polychaetes, these markers will be useful in assessing dispersal and gene flow in H. elegans and probably also other polychaetes.