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Exposure Of Nervous System Cells To Polychlorinated Biphenyls (Pcbs) Results In Significant Alterations In Levels Of Expression Of Neurotrophic Factors, Charles F. Ide, Jay C. Means, Trisha M. Basford, John Spitsbergen Jan 2003

Exposure Of Nervous System Cells To Polychlorinated Biphenyls (Pcbs) Results In Significant Alterations In Levels Of Expression Of Neurotrophic Factors, Charles F. Ide, Jay C. Means, Trisha M. Basford, John Spitsbergen

Biological Sciences Faculty and Graduate Student Research

Toxic insult by PCBs results in learning and memory deficits in humans. Alterations in expression of neurotrophic factors and/or their receptors have been linked to changes in cognition. How PCBs affect cognition is not known. We propose that PCBs affect cognition by altering neurotrophic factor expression or effects. We exposed cultured C6 glial cells in medium containing PCB (Aroclor 1254 (10ppm)). Control cells were treated with DMSO or regular medium. Cells were incubated at 37o C for up to 72 hours. Medium samples were taken at 6hr, 24hr, 48hr, and 72hr intervals. Enzyme-linked immunosorbent assays (ELISA) were used to determine …

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Size Doesn't Matter: Microbial Selection Experiments Address Ecological Phenomena, Michael Feldgarden, Daniel M. Stoebel, Dustin Brisson, Daniel E. Dykhuizen Jan 2003

Size Doesn't Matter: Microbial Selection Experiments Address Ecological Phenomena, Michael Feldgarden, Daniel M. Stoebel, Dustin Brisson, Daniel E. Dykhuizen

All HMC Faculty Publications and Research

Experimental evolution is relevant to ecology because it can connect physiology, and in particular metabolism, to questions in ecology. The investigation of the linkage between the environment and the evolution of metabolism is tractable because these experiments manipulate a very simple environment to produce predictable evolutionary outcomes. In doing so, microbial selection experiments can examine the causal elements of natural selection: how specific traits in varying environments will yield different fitnesses. Here, we review the methodology of microbial evolution experiments and address three issues that are relevant to ecologists: genotype-by-environment interactions, ecological diversification due to specialization, and negative frequency-dependent selection. …

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The Comparative Energetics And Growth Strategies Of Sympatric Antarctic And Sub Antarctic Fur Seal Pups, At Iles Crozet, J Py Arnould, S P. Luque, C Guinet, D P. Costa, J Kingston, Scott A. Shaffer Jan 2003

The Comparative Energetics And Growth Strategies Of Sympatric Antarctic And Sub Antarctic Fur Seal Pups, At Iles Crozet, J Py Arnould, S P. Luque, C Guinet, D P. Costa, J Kingston, Scott A. Shaffer

Faculty Publications, Biological Sciences

The period of maternal dependence is a time during which mammalian infants must optimise both their growth and the development of behavioural skills in order to successfully meet the demands of independent living. The rate and duration of maternal provisioning, post-weaning food availability and climatic conditions are all factors likely to influence the growth strategies of infants. While numerous studies have documented differences in growth strategies at high taxonomic levels, few have investigated those of closely related species inhabiting similar environments. The present study examined the body composition, metabolism and indices of physiological development in pups of Antarctic fur seals …

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When Does A Reproducing Female Viper (Vipera Aspis) ‘Decide’ On Her Litter Size?, Olivier Lourdais, Xavier Bonnet, Richard Shine, Emily N. Taylor Jan 2003

When Does A Reproducing Female Viper (Vipera Aspis) ‘Decide’ On Her Litter Size?, Olivier Lourdais, Xavier Bonnet, Richard Shine, Emily N. Taylor

Biological Sciences

Some organisms rely on stored energy to fuel reproductive expenditure (capital breeders) whereas others use energy gained during the reproductive bout itself (income breeders). Most species occupy intermediate positions on this continuum, but few experimental data are available on the timescale over which food intake can affect fecundity. Mark–recapture studies of free-ranging female aspic vipers Vipera aspis have suggested that reproductive output relies not only on the energy in fat bodies accumulated in previous years, but also on food intake immediately before ovulation. A simple experiment was conducted to test this hypothesis, maintaining female snakes in captivity throughout the vitellogenic …

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Extreme Water Velocities: Topographical Amplification Of Wave-Induced Flow In The Surf Zone Of Rocky Shores, Mark Denny, Luke Miller, M. Stokes, L. J. H. Hunt, B. S. T. Helmuth Jan 2003

Extreme Water Velocities: Topographical Amplification Of Wave-Induced Flow In The Surf Zone Of Rocky Shores, Mark Denny, Luke Miller, M. Stokes, L. J. H. Hunt, B. S. T. Helmuth

Faculty Publications, Biological Sciences

Water velocities as high as 25 m s-1 have been recorded in the surf zone of wave-swept rocky shores-velocities more than twice the phase speed of the breaking waves with which they are associated. How can water travel twice as fast as the waveform that initially induces its velocity? We explore the possibility that the interaction of a wave with the local topography of the shore can greatly amplify the water velocities imposed on intertidal plants and animals. Experiments in a laboratory wave tank show that interactions between bores refracted by a prowlike beach can produce jets in which the …

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Biodiversity And Biogeography Of The Islands Of The Kuril Archipelago [Abstract], Theodore W. Pietsch, Victor V. Bogatov, Kunio Amaoka, Yuri N. Zhuravlev, Vyacheslav Y. Barkalov, Sarah Gage, Hideki Takahashi, Arkady S. Lelej, Sergey Y. Storozhenko, Noboru Minakawa, Daniel J. Bennett, Trevor R. Anderson, Masahiro Ôhara, Larisa A. Prozorova, Yasuhiro Kuwahara, Sergey K. Kholin, Mamoru Yabe, Duane E. Stevenson, Erin L. Macdonald Jan 2003

Biodiversity And Biogeography Of The Islands Of The Kuril Archipelago [Abstract], Theodore W. Pietsch, Victor V. Bogatov, Kunio Amaoka, Yuri N. Zhuravlev, Vyacheslav Y. Barkalov, Sarah Gage, Hideki Takahashi, Arkady S. Lelej, Sergey Y. Storozhenko, Noboru Minakawa, Daniel J. Bennett, Trevor R. Anderson, Masahiro Ôhara, Larisa A. Prozorova, Yasuhiro Kuwahara, Sergey K. Kholin, Mamoru Yabe, Duane E. Stevenson, Erin L. Macdonald

Faculty Publications

No abstract provided.

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Accelerated Hatching Of Southern Leopard Frog (Rana Sphenocephala) Eggs In Response To The Presence Of A Crayfish (Procambarus Nigrocinctus) Predator, Daniel Saenz, James B. Johnson, Cory K. Adams, Gage H. Dayton Jan 2003

Accelerated Hatching Of Southern Leopard Frog (Rana Sphenocephala) Eggs In Response To The Presence Of A Crayfish (Procambarus Nigrocinctus) Predator, Daniel Saenz, James B. Johnson, Cory K. Adams, Gage H. Dayton

Faculty Publications

Phenotypic plasticity, such as morphological and behavioral changes in response to predators, is common in larval anurans. Less is known about inducible defenses in the embryonic stages of development. We investigated the predation risk imposed by crayfish (Procambarus nigrocinctus) on southern leopard frog (Rana sphenocephala) eggs aud whether crayfish presence induces a change in the timing of hatching of R. sphenocephala eggs. We found that crayfish significantly reduce the hatching success of R. sphenocephala eggs by eating them and that eggs hatch significantly faster in the presence of crayfish than when crayfish are not present. We …

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The Influence Of Predator Threat On The Timing Of A Life-History Switch Point: Predator-Induced Hatching In The Southern Leopard Frog (Rana Sphenocephala), James B. Johnson, Daniel Saenz, Cory K. Adams, Richard N. Conner Jan 2003

The Influence Of Predator Threat On The Timing Of A Life-History Switch Point: Predator-Induced Hatching In The Southern Leopard Frog (Rana Sphenocephala), James B. Johnson, Daniel Saenz, Cory K. Adams, Richard N. Conner

Faculty Publications

We tested the hypotheses that potential egg predators, crayfish Procambarus nigrocinctus and dytiscid Cybister sp. larvae, would accelerate the timing of hatching and that a larval predator, dragonfly naiad Anax junius, would delay hatching in the southern leopard frog (Rana sphenocephala). We also tested the hypothesis that differences in response would be proportional to predator lethality. Our results indicate that our hypotheses were partially supported. The presence of an efficient egg predator (crayfish) induces hatching faster than a less efficient predator (dytiscid larvae). However, the presence of a larval predator (naiads) did not delay hatching. Eggs that …

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Acoustic Communication In Two Freshwater Gobies: Ambient Noise And Short-Range Propagation In Shallow Streams, Marco Lugli, Michael L. Fine Jan 2003

Acoustic Communication In Two Freshwater Gobies: Ambient Noise And Short-Range Propagation In Shallow Streams, Marco Lugli, Michael L. Fine

Biology Publications

Noise is an important theoretical constraint on the evolution of signal form and sensory performance. In order to determine environmental constraints on the communication of two freshwater gobies Padogobius martensii and Gobius nigricans, numerous noise spectra weremeasured from quiet areas and ones adjacent to waterfalls and rapids in two shallow stony streams. Propagation of goby sounds and waterfall noise was also measured. A quiet window around 100 Hz is present in many noise spectra from noisy locations. The window lies between two noise sources, a low-frequency one attributed to turbulence, and a high-frequency one (200–500 Hz) attributed to bubble …

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Ethanol: A Better Preservation Technique For Daphnia, A. Ross Black, Stanley I. Dodson Jan 2003

Ethanol: A Better Preservation Technique For Daphnia, A. Ross Black, Stanley I. Dodson

Biology Faculty Publications

A 4% formalin-40% sucrose solution has been used by limnologists for three decades as the preferred freshwater zooplankton preservative because it kills and fixes cladocera (Branchiopoda) with relatively little distortion. Because of the increasing evidence of health hazards related to formalin, we sought an alternative, safer preservative that satisfies the need for low distortion. Our results suggest the ethanol preservative methods (70% and 95% treatments) are as good or better as using 4% sugar formalin to fix and store samples. Our results indicate the best method is to fix samples in 95% EtOH followed by storage in 70% EtOH. This …

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Review Of "Embryos In Wax: Models From The Ziegler Studio" By N. Hopwood, Scott F. Gilbert, J. Bard Jan 2003

Review Of "Embryos In Wax: Models From The Ziegler Studio" By N. Hopwood, Scott F. Gilbert, J. Bard

Biology Faculty Works

No abstract provided.

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Educating For Social Responsibility: Changing The Syllabus Of Developmental Biology, Scott F. Gilbert, A. Fausto-Sterling Jan 2003

Educating For Social Responsibility: Changing The Syllabus Of Developmental Biology, Scott F. Gilbert, A. Fausto-Sterling

Biology Faculty Works

Developmental biology is deeply embedded in the social issues of our times. Such topics as cloning, stems cells, reproductive technologies, sex selection, environmental hormone mimics and gene therapy all converge on developmental biology. It is therefore critical that developmental biologists learn about the possible social consequences of their work and of the possible molding of their discipline by social forces. We present two models for integrating social issues into the developmental biology curriculum. One model seeks to place discussions of social issues into the laboratory portion of the curriculum; the other model seeks to restructure the course, such that developmental …

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The Morphogenesis Of Evolutionary Developmental Biology, Scott F. Gilbert Jan 2003

The Morphogenesis Of Evolutionary Developmental Biology, Scott F. Gilbert

Biology Faculty Works

The early studies of evolutionary developmental biology (Evo-Devo) come from several sources. Tributaries flowing into Evo-Devo came from such disciplines as embryology, developmental genetics, evolutionary biology, ecology, paleontology, systematics, medical embryology and mathematical modeling. This essay will trace one of the major pathways, that from evolutionary embryology to Evo-Devo and it will show the interactions of this pathway with two other sources of Evo-Devo: ecological developmental biology and medical developmental biology. Together, these three fields are forming a more inclusive evolutionary developmental biology that is revitalizing and providing answers to old and important questions involving the formation of biodiversity on …

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Varriation Of Growth Rates In Yellow-Bellied Marmots, Carmen M. Salsbury, K. B. Armitage Jan 2003

Varriation Of Growth Rates In Yellow-Bellied Marmots, Carmen M. Salsbury, K. B. Armitage

Scholarship and Professional Work - LAS

Growth rates of yellow-bellied marmot (Marmota flaviventris) populations over a 32-year period (1965 -1996) varied Significantly with sex, age, location, and year. Overall, males had higher growth rates than females and young and yearlings generally had higher growth rates compared to adults at all locations. The locations varied with respect to elevation and the relationship between elevation and growth rate was complex and likely weather dependent. Low rainfall in late summer was often associated with low growth rates at high elevations where the active season is constrained and delayed by late spring snowmelt compared to low elevations. Growth rates and …

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Seasonal Body Temperature Fluctuations And Energetic Strategies In Free-Ranging Eastern Woodchucks, Carmen M. Salsbury Jan 2003

Seasonal Body Temperature Fluctuations And Energetic Strategies In Free-Ranging Eastern Woodchucks, Carmen M. Salsbury

Scholarship and Professional Work - LAS

During a 2-year period, radiotelemetry was used to continuously monitor body temperature ( T b) of free-ranging woodchucks (Marmota monax) in southeastern Pennsylvania. Hibernation was preceded by daily T b fluctuations ("test drops") of 2-4°C. During hibernation, woodchucks exhibited the characteristic pattern of torpor bouts. Time of arousals occurred randomly, but onset of torpor occurred predominantly between 1800 and 0000 h. Males had shorter hibernation periods (mean of 104.8 days) than did females (121.8 days). Males had shorter torpor bouts, but euthermic bouts were the same length as in females. Males also maintained higher T b during torpor. Overall, the …

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Long-Term Observations Of A Harbor Seal Haul-Out Site In A Protected Cove In Casco Bay, Gulf Of Maine, David Harris Phd, Barbarai Lelli, Sat Gupta Jan 2003

Long-Term Observations Of A Harbor Seal Haul-Out Site In A Protected Cove In Casco Bay, Gulf Of Maine, David Harris Phd, Barbarai Lelli, Sat Gupta

Faculty Publications

We counted the numbers of seals hauled out at low tide on two near-shore ledges in a protected cove in Casco Bay, Gulf of Maine a minimum of 12 times per month, for four years starting in August 1997. The highest mean monthly counts were in August (molting season) and the lowest in either January or February. Counts during pupping season (May and June) were lower than during April or July. As no mother-pup pairs were observed, these ledges are molting but not pupping ledges. Time-series analysis revealed no overall trend in the number of seals present. but did show …

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Are Hummingbirds Facultatively Ammonotelic? Nitrogen Excretion And Requirements As A Function Of Body Size, Todd J. Mcwhorter, Donald R. Powers, Carlos Martinez Del Rio Jan 2003

Are Hummingbirds Facultatively Ammonotelic? Nitrogen Excretion And Requirements As A Function Of Body Size, Todd J. Mcwhorter, Donald R. Powers, Carlos Martinez Del Rio

Faculty Publications - Department of Biological & Molecular Science

Most birds are uricotelic. An exception to this rule may be nectar-feeding birds, which excrete significant amounts of ammonia under certain conditions. Although ammonia is toxic, because it is highly water soluble its excretion may be facilitated in animals that ingest and excrete large amounts of water. Birdpollinated plants secrete carbohydrate- and water-rich floral nectars that contain exceedingly little protein. Thus, nectarfeeding birds are faced with the dual challenge of meeting nitrogen requirements while disposing of large amounts of water. The peculiar diet of nectar-feeding birds suggests two hypotheses: (1) these birds must have low protein requirements, and (2) when …

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Hypothalamic Proopiomelanocortin Neurons Are Glucose Responsive And Express Katp Channels, Nurhadi Ibrahim, Martha A. Bosch, James L. Smart, Jian Qiu, Marcelo Rubinstein, Oline K. Rønnekleiv, Malcolm J. Low, Martin J. Kelly Jan 2003

Hypothalamic Proopiomelanocortin Neurons Are Glucose Responsive And Express Katp Channels, Nurhadi Ibrahim, Martha A. Bosch, James L. Smart, Jian Qiu, Marcelo Rubinstein, Oline K. Rønnekleiv, Malcolm J. Low, Martin J. Kelly

Faculty Publications - Department of Biological & Molecular Science

Hypothalamic proopiomelanocortin (POMC) neurons are critical for controlling homeostatic functions in the mammal. We used a transgenic mouse model in which the POMC neurons were labeled with enhanced green fluorescent protein to perform visualized, whole-cell patch recordings from prepubertal female hypothalamic slices. The mouse POMC-enhanced green fluorescent protein neurons expressed the same endogenous conductances (a transient outward K current and a hyperpolarization-activated, cation current) that have been described for guinea pig POMC neurons. In addition, the selective -opioid receptor agonist DAMGO induced an outward current (maximum of 12.8 1.2 pA), which reversed at K equilibrium potential (EK), in the majority …

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The Anorexigenic Fatty Acid Synthase Inhibitor, C75, Is A Nonspecific Neuronal Activator, Kanji A. Takahashi, James L. Smart, Hongyan Liu, Roger D. Cone Jan 2003

The Anorexigenic Fatty Acid Synthase Inhibitor, C75, Is A Nonspecific Neuronal Activator, Kanji A. Takahashi, James L. Smart, Hongyan Liu, Roger D. Cone

Faculty Publications - Department of Biological & Molecular Science

C75, a recently derived compound that potently suppresses feeding and induces weight loss, has been proposed to act mainly by inhibiting fatty acid synthase (FAS) in central neurons that control feeding. For example, normal, fasting- associated, hypothalamic increases in neuropeptide Y (NPY)/Agouti-related protein (AGRP) expression and decreases in proopiomelanocortin (POMC)/cocaine and amphetamine regulated transcript (CART) expression were reported to be blocked by C75. Using loose-patch extracellular recording in acute slices, we tested the effect of C75 on anorexigenic POMC neurons and orexigenic NPY neurons of the hypothalamic arcuate nucleus, which were identified by promoter-driven GFP expression, as well as on …

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Regulation Of Proto-Oncogenes Expression In Developmental Epilepsy, Mahnoush Shafiei Jan 2003

Regulation Of Proto-Oncogenes Expression In Developmental Epilepsy, Mahnoush Shafiei

Seton Hall University Dissertations and Theses (ETDs)

Seizures cause selective neuronal cell loss in vulnerable regions such as the hippocampus, cortex, thalamus or substantia nigra (SN) in human or experimental animals. While the HF can propagate seizures, the SN pars reticulata (SNR) regulates the spread ol seizures in an age-dependent fashion, and the pars compacta (SNC) affects extrapyramidal motor control. In mature animals, both structures are wlnerable to seizure-induced damage. In prepubescent rats, seizure susceptibility is reduced and CA 1 region rs primarily affected. The proto-oncogenes, Bcl-2 and Bax, encode specific proteins that inhibit and promote programmed cell death, respectively. In order to determine whether proto-oncogenes are …

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The Evolution Of Social And Reproductive Monogamy In Peromyscus, Evidence From Peromyscus Californicus (The California Mouse), David O. Ribble Jan 2003

The Evolution Of Social And Reproductive Monogamy In Peromyscus, Evidence From Peromyscus Californicus (The California Mouse), David O. Ribble

Biology Faculty Research

The genus Peromyscus (deer mice) is an attractive group in which to study the evolution of social and mating behaviours. This genus includes over 50 species (Carleton, 1989) that are widely distributed across North and Central America from coast to coast and from the northern subarctic to Panama (Kirkland & Layne, 1989). The diversity in body sizes among Peromyscus ranges from 13 to 77 g (Millar, 1989) and exceeds that of most other genera. Phylogenetic relationships among species of Peromyscus are relatively well understood (Stangl & Baker, 1984), although the systematics of Peromyscus is an active area of study (e.g., …

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Growth And The Expression Of Alternative Life Cycles In The Salamander Ambystoma Talpoideum (Caudata: Ambystomatidae), Travis J. Ryan, Raymond D. Semlitsch Jan 2003

Growth And The Expression Of Alternative Life Cycles In The Salamander Ambystoma Talpoideum (Caudata: Ambystomatidae), Travis J. Ryan, Raymond D. Semlitsch

Scholarship and Professional Work - LAS

Complex life cycles (CLCs) contain larval and adult phases that are morphologically and ecologically distinct. Simple life cycles (SLCs) have evolved from CLCs repeatedly in a wide variety of lineages but the processes that may underlie the transition have rarely been identified or investigated experimentally. We examined the influence of larval growth rate on the facultative expression of alternative life cycles (metamorphosis or maturation as gill-bearing adults [= paedomorphosis]) in the salamander Ambystoma talpoideum. We manipulated growth rates by altering the amount of food individuals received throughout larval development. The expression of alternative life cycles in A. talpoideum is influenced …

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An Ecological Study Of The Spotted Salamander, Ambystoma Maculatum, And Jefferson Salamander, A. Jeffersonianum, In West Virginia, Seth J. Myers Jan 2003

An Ecological Study Of The Spotted Salamander, Ambystoma Maculatum, And Jefferson Salamander, A. Jeffersonianum, In West Virginia, Seth J. Myers

Theses, Dissertations and Capstones

The movements of Spotted Salamanders, Ambystoma maculatum, and Jefferson Salamanders, A. jeffersonianum, in and out of an ephemeral wetland in West Virginia were monitored for one breeding season using a drift fence lined with funnel traps. Significant movements of A. jeffersonianum coincided with rainfall and maximum daily air temperatures reaching a minimum of 5° C. Significant movements of A. maculatum coincided with rainfall and maximum daily air temperatures of at least 10° C. A. jeffersonianum preceded A. maculatum to the breeding site. Males of both species preceded females. The mark-recapture estimate of A. maculatum is 67 males and 25 females. …

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Anorexia, Bulimia, And Crayfish (Or, Why I Study The Pharmacology Of Serotonin Receptors In Glutamatergic Invertebrate Systems), Garrett Sparks Jan 2003

Anorexia, Bulimia, And Crayfish (Or, Why I Study The Pharmacology Of Serotonin Receptors In Glutamatergic Invertebrate Systems), Garrett Sparks

Kaleidoscope

No abstract provided.

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Serpents Of The Ark-La-Tex, Jennifer L. Hollis Jan 2003

Serpents Of The Ark-La-Tex, Jennifer L. Hollis

Presidential Scholars Theses (1990 – 2006)

Slides and notes from a presentation focusing on the snakes of western Arkansas, northeastern Texas, and the Edwards Plateau of central Texas.

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Effects Of A Yec Apologetics Class On Student Worldview, David A. Dewitt, Steve Deckard, Sharon E. Cargo Jan 2003

Effects Of A Yec Apologetics Class On Student Worldview, David A. Dewitt, Steve Deckard, Sharon E. Cargo

Faculty Publications and Presentations

Creationism is a significant component of an overall Christian worldview. A Creation Worldview Test (CWT) was administered to students both before and after completion of a required Apologetics course dealing with the creation/evolution controversy. Pre-test analysis revealed that incoming students tend to have a creationist worldview, however their CWT scores reflected a degree of uncertainty or neutrality on scientific creation and the age of the earth. Post-test analysis showed a significant shift toward a young earth creationist (YEC) view. Implications for teaching apologetics and development of a Creationist worldview based on a Six-day Young Earth perspective were explored and identified.

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Quorum Sensing In Gram-Negative Bacteria, Gülgün Boşgelmez Tinaz Jan 2003

Quorum Sensing In Gram-Negative Bacteria, Gülgün Boşgelmez Tinaz

Turkish Journal of Biology

It has become increasingly and widely recognised that bacteria do not live as isolated entities but instead exist as communities that exploit elaborate systems of intercellular communication to facilitate their adaptation to changing environmental conditions. A well-characterised example of such intercellular communication is quorum sensing. Quorum sensing depends on the production of diffusible signal molecules termed autoinducers or pheromones, which enable a bacterium to monitor its own cell population density. A variety of physiological processes in a range of bacterial species is regulated by quorum sensing. Examples include bioluminescence, antibiotic biosynthesis, swarming, biofilm differentiation, conjugation and the production of virulence …

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Melatonin Implants Have No Effect On The Testis Volume And Body Weight In Mongolian Gerbils, Alper Karakaş, Bülent Gündüz Jan 2003

Melatonin Implants Have No Effect On The Testis Volume And Body Weight In Mongolian Gerbils, Alper Karakaş, Bülent Gündüz

Turkish Journal of Biology

Photoperiod is an important environmental cue in the regulation of reproductive activity in Mongolian gerbils. Photoperiodic information is ultimately transduced into a hormonal signal by the pineal gland. We examined the effect of constant-release melatonin capsules on the testicular size and body weights of male Mongolian gerbils exposed to a long (14L: 10D) photoperiod. Three groups were formed: control (n = 10), intact + melatonin implant (n = 10) and pinealectomy + melatonin implant (n = 10). The testes and body weights of the gerbils were recorded every week for 8 weeks. Body weights (76 ± 2.0 g intact + …

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The Effect Of Aposematic Coloration On The Food Preference Of Aphelocoma Coerulescens, The Florida Scrub Jay, Mary Elizabeth Hill Jan 2003

The Effect Of Aposematic Coloration On The Food Preference Of Aphelocoma Coerulescens, The Florida Scrub Jay, Mary Elizabeth Hill

Theses and Dissertations

Aposematic coloration, commonly observed in noxious organisms, serves as a warning to predators to avoid attacking specific prey. This coloration is conspicuous in nature, with one of the most common examples being a red and black pattern. The plant Abrus precatorius exhibits this warning signal in its seeds, which resemble lady beetles and contain the concentrated toxin abrin. Aphelocoma coerulescens, an endemic and federally threatened bird in the state of Florida, shares a similar distribution with Abrus precatorius, making interaction between the two species possible. Using an edible model of the Abrus seed, this potential interaction was tested in Martin …

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Embryogenesis In The Japanese Medaka, Oryzias Latipes, Laura Harris Harris, Lisa Sims, Roxann Stachiw Jan 2003

Embryogenesis In The Japanese Medaka, Oryzias Latipes, Laura Harris Harris, Lisa Sims, Roxann Stachiw

Journal of the South Carolina Academy of Science

No abstract provided.

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