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Opportunities For Public Aquariums To Increase The Sustainability Of The Aquatic Animal Trade, Michael F. Tlusty, Andrew L. Rhyne, Les Kaufman, Michael Hutchins, Gordon Mcgregor Reid, Chris Andrews, Paul Boyle, Jay Hemdal, Frazer Mcgilvray, Scott Dowd Jan 2012

Opportunities For Public Aquariums To Increase The Sustainability Of The Aquatic Animal Trade, Michael F. Tlusty, Andrew L. Rhyne, Les Kaufman, Michael Hutchins, Gordon Mcgregor Reid, Chris Andrews, Paul Boyle, Jay Hemdal, Frazer Mcgilvray, Scott Dowd

Arts & Sciences Faculty Publications

The global aquatic pet trade encompasses a wide diversity of freshwater and marine organisms. While relying on a continual supply of healthy, vibrant aquatic animals, few sustainability initiatives exist within this sector. Public aquariums overlap this industry by acquiring many of the same species through the same sources. End users are also similar, as many aquarium visitors are home aquarists. Here we posit that this overlap with the pet trade gives aquariums significant opportunity to increase the sustainability of the trade in aquarium fishes and invertebrates. Improving the sustainability ethos and practices of the aquatic pet trade can carry a …


In Vivo Evaluation Of Microfibrous Bioactive Borate Glasses For Use In Wound Healing, Yinan Lin Jan 2012

In Vivo Evaluation Of Microfibrous Bioactive Borate Glasses For Use In Wound Healing, Yinan Lin

Masters Theses

"This project consisted of two parts focused on in vivo evaluation of microfibrous bioactive borate glasses for use in wound healing. Part one of the project involved subcutaneous implantation of two types of borate glass microfibers and 45S5 glass micro fibers in the dorsum of rats and histologically evaluating the soft tissues at the implant sites at 2 to 4 weeks post surgery. The primary objective was to assess the angiogenic response to the implanted materials. The 13-93B3 and 13-93B3Cu glass microfibers were found to significantly increase the microvascular density in soft tissue, an outcome that suggests these simple and …


Recent Developments In The Interactions Between Caveolin And Pathogens, Fabiana S. Machado, Nilda E. Rodriguez, Daniel Adesse, Luciana R. Garzoni, Lisia Esper, Michael P. Lisanti, Robert D. Burk, Chris Albanese, Koenraad Van Doorslaer, Louis M. Weiss, Fnu Nagajyothi, Joshua D. Nosanchuk, Mary E. Wilson, Herbert B. Tanowitz Jan 2012

Recent Developments In The Interactions Between Caveolin And Pathogens, Fabiana S. Machado, Nilda E. Rodriguez, Daniel Adesse, Luciana R. Garzoni, Lisia Esper, Michael P. Lisanti, Robert D. Burk, Chris Albanese, Koenraad Van Doorslaer, Louis M. Weiss, Fnu Nagajyothi, Joshua D. Nosanchuk, Mary E. Wilson, Herbert B. Tanowitz

Faculty Work

The role of caveolin and caveolae in the pathogenesis of infection has only recently been appreciated. In this chapter, we have highlighted some important new data on the role of caveolin in infections due to bacteria, viruses and fungi but with particular emphasis on the protozoan parasites Leishmania spp., Trypanosoma cruzi and Toxoplasma gondii. This is a continuing area of research and the final chapter has not been written on this topic.


Aging Phenotypes Of Common Marmosets (Callithrix Jacchus), Corinna N. Ross, K. Davis, G. Dobek, S. D. Tardif Jan 2012

Aging Phenotypes Of Common Marmosets (Callithrix Jacchus), Corinna N. Ross, K. Davis, G. Dobek, S. D. Tardif

Biology Faculty Publications (Archived)

Characterizing the phenotypic changes associated with aging in a short-lived primate is necessary in order to develop better translational models for human health, aging, and disease research. A population of conventionally housed marmoset monkeys was assessed to determine if phenotypes of body composition, hematology, and morphometrical measures were associated with age or risk of death. We found that the cause of mortality in older marmosets was more likely to be due to cardiac and chronic kidney disease than in younger marmosets. Older marmosets have decreased fat mass, morphometric measures, and serum albumin. Older marmosets are more likely to show a …


Growth Performance, Yields And Economic Benefits Of Nile Tilapia Oreochromis Niloticus And Kales Brassica Oleracea Cultured Under Vegetable-Fish Culture Integration, A. P. Shoko, A. Getabu, G. Mwayuli, Y. D. Mgaya Dec 2011

Growth Performance, Yields And Economic Benefits Of Nile Tilapia Oreochromis Niloticus And Kales Brassica Oleracea Cultured Under Vegetable-Fish Culture Integration, A. P. Shoko, A. Getabu, G. Mwayuli, Y. D. Mgaya

Tanzania Journal of Science

An experiment was conducted for 210 days to demonstrate the role of vegetable-fish culture integration in the growth, yields and economic benefits of fish and vegetables. Two 200 m2 earthen fishponds were stocked with Nile tilapia Oreochromis niloticus at 20,000 fish fingerlings per hectare. Pond A was fertilized with chicken manure and stocked fish fed on 35% crude protein supplementary diet referred to here as treated fish pond (TFP). Another fish pond was not fertilized and the fish stocked in it did not receive any supplementary diet referred to here as non treated fish pond (NTFP). Twelve vegetable plots of …


Natural Variation In Gestational Cortisol Is Associated With Patterns Of Growth In Marmoset Monkeys (Callithrix Geoffroyi), Aaryn C. Mustoe, Andrew K. Birnie, Andrew V. Korgan, Jonathan Bruce Santo, Jeffrey French Dec 2011

Natural Variation In Gestational Cortisol Is Associated With Patterns Of Growth In Marmoset Monkeys (Callithrix Geoffroyi), Aaryn C. Mustoe, Andrew K. Birnie, Andrew V. Korgan, Jonathan Bruce Santo, Jeffrey French

Psychology Faculty Publications

High levels of prenatal cortisol have been previously reported to retard fetal growth. Although cortisol plays a pivotal role in prenatal maturation, heightened exposure to cortisol can result in lower body weights at birth, which have been shown to be associated with adult diseases like hypertension and cardiovascular disease. This study examines the relationship between natural variation in gestational cortisol and fetal and postnatal growth in marmoset monkeys. Urinary samples obtained during the mother’s gestation were analyzed for cortisol. Marmoset body mass index (BMI) was measured from birth through 540 days in 30- or 60-day intervals. Multi-level modeling was used …


Role Of Pseudomonas Produced Hydrogen Cyanide In Biological Control Of Plant-Parasitic Nematodes, Haytham Aly Dec 2011

Role Of Pseudomonas Produced Hydrogen Cyanide In Biological Control Of Plant-Parasitic Nematodes, Haytham Aly

Dissertations

Plant-parasitic nematodes are among the most devastating pests world-wide, causing extensive damage to important agriculture crops. The management of nematodes is challenging. Current methods used for nematode control rely mostly on using chemical nematicides and naturally resistant plants. Because of serious health and environmental problems associated with chemical control and over use of resistant plants resulting in resistant breaking strains of nematodes, alternative nematode-control methods are needed. Several potential nematode-biocontrol agents, including bacteria and fungi, have been studied for their antagonistic effect toward plant-parasitic nematodes. However, a concise picture about the biological agent’s mechanisms used to antagonize nematodes remains elusive. …


Effects Of The Exotic Shrub Lonicera Maackii On The Plant Animal Interactions In The Invaded Habitat, Humberto De Paula Dutra Dec 2011

Effects Of The Exotic Shrub Lonicera Maackii On The Plant Animal Interactions In The Invaded Habitat, Humberto De Paula Dutra

Dissertations

Invasive plants are an economical, political, social, and ecological problem. Some invasive species are a serious concern for society because some of them are diseases, some are agricultural pests, and some become major threats to the ecosystems. Most studies with invasive species are limited because they measure only the impact of the invasion via direct pathways. Unfortunately, the potential for non-native plant species to alter ecosystem functions via indirect pathways mediated by interactions with animals just recently became broadly recognized. This research investigates the interactions of Amur honeysuckle with native fauna and how these interactions indirectly affect other trophic levels …


Reproducible Hairy Root Transformation And Spot-Inoculation Methods To Study Root Symbioses Of Pea, Scott R. Clemow, Lindsey Clairmont, Lene H. Madsen, Frédérique C. Guinel Dec 2011

Reproducible Hairy Root Transformation And Spot-Inoculation Methods To Study Root Symbioses Of Pea, Scott R. Clemow, Lindsey Clairmont, Lene H. Madsen, Frédérique C. Guinel

Biology Faculty Publications

Pea has lagged behind other model legumes in the molecular study of nodulation and mycorrhizae-formation because of the difficulty to transform its roots and its poor growth on agar plates. Here we describe for pea 1) a transformation technique which permits the complementation of two known non-nodulating pea mutants, 2) a rhizobial inoculation method which allows the study of early cellular events giving rise to nodule primordia, and 3) a targeted fungal inoculation method which allows us to study short segments of mycorrhizal roots assured to be infected. These tools are certain to advance our knowledge of pea root symbioses.


Selectivity Of Prey Capture Based On Prey Size In The Venus Fly Trap (Dionaea Muscipula Ellis), Jessica Humenik Dec 2011

Selectivity Of Prey Capture Based On Prey Size In The Venus Fly Trap (Dionaea Muscipula Ellis), Jessica Humenik

Honors Theses

Venus fly traps (Dionaea muscipula Ellis) are carnivorous plants that live in nutrient poor soils and must digest insects to supplement their diets. When a Venus fly trap captures an insect, the plant's traps do not fully close for several minutes, which may allow small prey to escape. It would be beneficial for the plant to consume a large, nutrient-rich prey item as opposed to a small prey item. We tested the hypothesis that Venus fly traps select larger prey by offering plants small and large crickets. A Kruskal-Wallis test and Wilcoxon signed rank test were used to test significance …


What Are The Effects Of Raw Vs. Pasteurized Milk Consumption On Growth Rate And Fertility In A Colony Of Mice?, Kari Sholing, Lindsay Ganong, Amy Olson Dec 2011

What Are The Effects Of Raw Vs. Pasteurized Milk Consumption On Growth Rate And Fertility In A Colony Of Mice?, Kari Sholing, Lindsay Ganong, Amy Olson

Nutrition Student Work

Interest in consuming unprocessed foods has led to assumptions that raw milk has health benefits over pasteurized milk. This study was designed to evaluate the belief that raw milk is nutritionally superior. Eighteen mice were randomly assigned to one of two groups: raw milk or pasteurized milk. Mice were grouped into breeding trios and given a fresh supply of milk every four hours between 7 a.m. and 11 p.m. for 55 days. Milk consumption was tracked at each feeding by measuring the amount of milk that was provided and the amount of milk that was left from the previous feeding. …


Suppression Of Phospholipase Dγs Confers Increased Aluminum Resistance In Arabidopsis Thaliana, Xuemin Wang, Jian Zhao, Cunxi Wang, Mohamed Bedair, Ruth Welti, Lloyd Sumner, Ivan Baxter Dec 2011

Suppression Of Phospholipase Dγs Confers Increased Aluminum Resistance In Arabidopsis Thaliana, Xuemin Wang, Jian Zhao, Cunxi Wang, Mohamed Bedair, Ruth Welti, Lloyd Sumner, Ivan Baxter

Biology Department Faculty Works

Aluminum (Al) toxicity is the major stress in acidic soil that comprises about 50% of the world's arable land. The complex molecular mechanisms of Al toxicity have yet to be fully determined. As a barrier to Al entrance, plant cell membranes play essential roles in plant interaction with Al, and lipid composition and membrane integrity change significantly under Al stress. Here, we show that phospholipase Dγs (PLDγs) are induced by Al stress and contribute to Al-induced membrane lipid alterations. RNAi suppression of PLDγ resulted in a decrease in both PLDγ1 and PLDγ2 expression and an increase in Al resistance. Genetic …


Expanding The Temporal Dimensions Of Developmental Biology: The Role Of Environmental Agents In Establishing Adult-Onset Phenotypes, Scott F. Gilbert Dec 2011

Expanding The Temporal Dimensions Of Developmental Biology: The Role Of Environmental Agents In Establishing Adult-Onset Phenotypes, Scott F. Gilbert

Biology Faculty Works

Developmental biology is expanding into several new areas. One new area of study concerns the production of adult-onset phenotypes by exposure of the fetus or neonate to environmental agents. These agents include maternal nutrients, developmental modulators (endocrine disruptors), and maternal care. In all three cases, a major mechanism for the generation of the altered phenotype is chromatin modification. Nutrient conditions, developmental modulators, and even maternal care appear to alter DNA methylation and other associated changes in chromatin that regulate gene expression. This brings a new, under-appreciated, dimension of gene regulation into developmental biology, and it also demonstrates the poverty of …


Infectious Disease And The Worldwide Distribution Of Iq, Christopher Guiles Eppig Dec 2011

Infectious Disease And The Worldwide Distribution Of Iq, Christopher Guiles Eppig

Biology ETDs

We show that infectious disease is a major contributor to the worldwide distribution of human cognitive ability, as measured by psychometric IQ. In areas where infectious disease is high, average human intelligence tends to be lower, and in areas where infectious disease is low, average human intelligence tends to be higher. In separate studies, we tested this across world nations (chapter 2) and across states of the USA (chapter 3). In efforts to disseminate our research to wider audiences, I reviewed the findings contained in chapters 2 and 3 using language that is accessible to non-biologists (chapter 4). Although it …


Abiotic Stress Responses In Photosynthetic Organisms, Joseph Msanne Dec 2011

Abiotic Stress Responses In Photosynthetic Organisms, Joseph Msanne

School of Natural Resources: Dissertations, Theses, and Student Research

Cellular and molecular aspects of abiotic stress responses in Arabidopsis thaliana subjected to cold, drought, and high salinity and in two photosynthetic green alga, Chlamydomonas reinhardtii and Coccomyxa sp. C-169, subjected to nitrogen deprivation were investigated. Cold, drought, and high salinity can negatively affect plant growth and crop production. The first research aimed at determining the physiological functions of the stress-responsive Arabidopsis thaliana RD29A and RD29B genes. Cold, drought, and salt induced both genes; the promoter of RD29Awas found to be more responsive to drought and cold stresses, whereas the promoter of RD29B was highly responsive to salt stress. …


The Role Of Receptor Tyrosine Kinase Axl In Pancreatic Ductal Adenocarcinoma And Its Regulation By Hematopoietic Progenitor Kinase 1, Xianzhou Song Dec 2011

The Role Of Receptor Tyrosine Kinase Axl In Pancreatic Ductal Adenocarcinoma And Its Regulation By Hematopoietic Progenitor Kinase 1, Xianzhou Song

Dissertations and Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDA) is one of the most aggressive malignancies with less than 5% of five year survival rate. New molecular markers and new therapeutic targets are urgently needed for patients with PDA. Oncogenic receptor tyrosine kinase Axl has been reported to be overexpressed in many types of human malignancies, including diffuse glioma, melanoma, osteosarcoma, and carcinomas of lung, colon, prostate, breast, ovary, esophagus, stomach, and kidney. However, the expression and functions of Axl in PDA are unclear. We hypothesized that Axl contributes to the development and progression of PDA. We examined Axl expression in 54 human PDA samples …


Effect Of Voluntary Exercise And Diet On The Unfolded Protein Response In The Brain Of Mice, Yu Ho Kim Dec 2011

Effect Of Voluntary Exercise And Diet On The Unfolded Protein Response In The Brain Of Mice, Yu Ho Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The medical costs for many chronic diseases are increasing dramatically and placing a major financial burden on nations and individuals in both developed and developing countries. A number of chronic diseases, such as obesity, type 2 diabetes and some neurodegenerative diseases are all attenuated by a history of physical activity suggesting that they may be interconnected in some way. It has been suggested that cellular stress is a major factor promoting these chronic diseases.

Cellular stress occurs in a specific compartment within the cell, the endoplasmic reticulum, whose normal function is in the synthesis and folding of proteins into the …


Thermal Tolerance Of Age-0 Gulf Of Mexico Striped Bass (Morone Saxatilis): Ontogenetic And Genetic Effects, Corey Robert Anderson Dec 2011

Thermal Tolerance Of Age-0 Gulf Of Mexico Striped Bass (Morone Saxatilis): Ontogenetic And Genetic Effects, Corey Robert Anderson

Master's Theses

Striped bass, Morone saxatilis, were historically abundant in the Gulf of Mexico region but were largely extirpated from most Gulf rivers by the early 1960s. Since 1967 hatchery stocking has supported populations in Mississippi rivers and to date there is no evidence of natural reproduction. Intolerance of striped bass to high water temperature is a potential factor negatively impacting Gulf striped bass survival and reproductive fitness, and may be a limiting factor to reintroduction of the species in Mississippi. This work contributed to restoration efforts by establishing molecular tools necessary for genetic monitoring of striped bass restoration, and evaluating …


Tick Infestations And Their Consequences For Migratory Songbirds During Spring Stopover, Johnny Michael Sellers Jr. Dec 2011

Tick Infestations And Their Consequences For Migratory Songbirds During Spring Stopover, Johnny Michael Sellers Jr.

Master's Theses

Migratory birds face a number of challenges during their seasonal movement from tropical/sub-tropical Central and South America to more temperate North America. Maintaining health during migration is of particular concern. This study seeks to understand how haematophageous ectoparasites, such as ticks (Ixodida), impact host body condition as they feed on passerines during migration. We hypothesized that foraging location would impact tick acquisition by migrants and that tick burdens during migration would negatively impact body condition. We surveyed 2,064 birds during spring 2009 and 2010 and found that 2.4% of the surveyed birds were infested with one or more …


Influence Of Detritus Levels And Organic Pollution On Interspecific Resource Competition, Oviposition Behavior, And Larval Survival Of Two Tire-Inhabiting Mosquito Species (Diptera: Culicidae), David Wayne Allgood Dec 2011

Influence Of Detritus Levels And Organic Pollution On Interspecific Resource Competition, Oviposition Behavior, And Larval Survival Of Two Tire-Inhabiting Mosquito Species (Diptera: Culicidae), David Wayne Allgood

Master's Theses

Mosquitoes (Diptera: Culicidae) are vectors of disease in the adult stage, but understanding the factors affecting distributions of the immature stages is important to the understanding and control of adult populations. Discarded automobile tires comprise important larval mosquito habitats. The Asian tiger mosquito (Aedes albopictus) and the southern house mosquito (Culex quinquefasciatus) are two medically important species commonly found in tires, but factors affecting their larval distributions in tires have not been studied, nor have their interspecific interactions. I investigated the effects of chemicals associated with organic pollution on oviposition preferences and larval survival of both …


Phylogenomics Of Reichenowia Parasitica, An Alphaproteobacterial Endosymbiont Of The Freshwater Leech Placobdella Parasitica, Sebastian Kvist, Apurva Narechania, Alejandro Oceguera-Figueroa, Bella Fuks, Mark E. Siddall Nov 2011

Phylogenomics Of Reichenowia Parasitica, An Alphaproteobacterial Endosymbiont Of The Freshwater Leech Placobdella Parasitica, Sebastian Kvist, Apurva Narechania, Alejandro Oceguera-Figueroa, Bella Fuks, Mark E. Siddall

Publications and Research

Although several commensal alphaproteobacteria form close relationships with plant hosts where they aid in (e.g.,) nitrogen fixation and nodulation, only a few inhabit animal hosts. Among these, Reichenowia picta, R. ornata and R. parasitica, are currently the only known mutualistic, alphaproteobacterial endosymbionts to inhabit leeches. These bacteria are harbored in the epithelial cells of the mycetomal structures of their freshwater leech hosts, Placobdella spp., and these structures have no other obvious function than housing bacterial symbionts. However, the function of the bacterial symbionts has remained unclear. Here, we focused both on exploring the genomic makeup of R. parasitica and on …


Traversing Swanton Road, 6th Ed., James A. West Nov 2011

Traversing Swanton Road, 6th Ed., James A. West

Academic, Government & Associated Organizational Research Resources

Situated at the northwest end of Santa Cruz County and occupying circa 30 square miles of sharply contrasted terrain, the Scott Creek Watershed concentrates within its geomorphological boundaries, at least 10-12% of California's flora, both native and introduced. Paradoxically, the use/abuse that the watershed has sustained over the past 140+ years, has not necessarily diminished the biodiversity and perhaps parallels the naturally disruptive but biologically energizing processes (fire, flooding, landslides and erosion), which have also been historically documented for the area for +60 years. This is an early edition of an extensive document by James A. West. Please visit the …


Investigating The Roles Of Ndj1 And Tid1 In Crossover Assurance In Saccharomyces Cerevisiae, Rianna Knowles Nov 2011

Investigating The Roles Of Ndj1 And Tid1 In Crossover Assurance In Saccharomyces Cerevisiae, Rianna Knowles

Master's Theses

Meiosis is the specialized process of cell division utilized during gametogenesis in all sexually reproducing eukaryotes, which consists of one round of DNA replication followed by two rounds of chromosome segregation and results in four haploid cells. Crossovers between homologous chromosomes promote proper alignment and segregation of chromosomes during meiosis.

Crossover interference is a genetic phenomenon in which crossovers are non-randomly placed along chromosomes. Crossover assurance ensures that every homologous chromosome pair obtains at least one crossover during Prophase I. Crossovers physically connect homologous pairs, allowing spindle fibers to attach and separate homologs properly. However, some organisms have shown an …


Loss-Of-Function Of Constitutive Expresser Of Pathogenesis Related Genes5 Affects Potassium Homeostasis In Arabidopsis Thaliana, Monica Borghi, Ana Rus, David E. Salt Oct 2011

Loss-Of-Function Of Constitutive Expresser Of Pathogenesis Related Genes5 Affects Potassium Homeostasis In Arabidopsis Thaliana, Monica Borghi, Ana Rus, David E. Salt

Biology Faculty Publications

Here, we demonstrate that the reduction in leaf K+ observed in a mutant previously identified in an ionomic screen of fast neutron mutagenized Arabidopsis thaliana is caused by a loss-of-function allele of CPR5, which we name cpr5-3. This observation establishes low leaf K+ as a new phenotype for loss-of-function alleles of CPR5. We investigate the factors affecting this low leaf K+ in cpr5 using double mutants defective in salicylic acid (SA) and jasmonic acid (JA) signalling, and by gene expression analysis of various channels and transporters. Reciprocal grafting between cpr5 and Col-0 was used to determine the relative importance of …


The Group-Level Consequences Of Sexual Conflict In Multigroup Populations, Omar Tonsi Eldakar, Andrew C. Gallup Oct 2011

The Group-Level Consequences Of Sexual Conflict In Multigroup Populations, Omar Tonsi Eldakar, Andrew C. Gallup

Biology Faculty Articles

In typical sexual conflict scenarios, males best equipped to exploit females are favored locally over more prudent males, despite reducing female fitness. However, local advantage is not the only relevant form of selection. In multigroup populations, groups with less sexual conflict will contribute more offspring to the next generation than higher conflict groups, countering the local advantage of harmful males. Here, we varied male aggression within-and between-groups in a laboratory population of water striders and measured resulting differences in local population growth over a period of three weeks. The overall pool fitness (i.e., adults produced) of less aggressive pools exceeded …


Demasculinization And Feminization Of Male Gonads By Atrazine: Consistent Effects Across Vertebrate Classes, Krista A. Mccoy Oct 2011

Demasculinization And Feminization Of Male Gonads By Atrazine: Consistent Effects Across Vertebrate Classes, Krista A. Mccoy

Integrative Biology Faculty and Staff Publications

Atrazine is the most commonly detected pesticide contaminant of ground water, surface water, and precipitation. Atrazine is also an endocrine disruptor that, among other effects, alters male reproductive tissues when animals are exposed during development. Here, we apply the nine so-called “Hill criteria” (Strength, Consistency, Specificity, Temporality, Biological Gradient, Plausibility, Coherence, Experiment, and Analogy) for establishing cause–effect relationships to examine the evidence for atrazine as an endocrine disruptor that demasculinizes and feminizes the gonads of male vertebrates. We present experimental evidence that the effects of atrazine on male development are consistent across all vertebrate classes examined and we present a …


Composition Of Suspended And Benthic Particulate Matter In The Tidal Freshwater James River, Anne Schlegel Sep 2011

Composition Of Suspended And Benthic Particulate Matter In The Tidal Freshwater James River, Anne Schlegel

Theses and Dissertations

Investigating linkages between the compositions of suspended (seston) and benthic particulate matter is important to the understanding of organic matter (OM) cycling and nutrient retention in aquatic systems. We compared the quantity and quality of the truly suspended (TS) and settleable (SB) fractions of seston as well as benthic particulate matter in the tidal freshwater James River, Virginia. The mass of seston and OM was consistently higher in the TS fraction compared to the SB fraction. OM was preferentially retained in the TS fraction relative to seston. The proportional contribution of OM constituents (chlorophyll a, particulate organic carbon and nitrogen) …


Rhythmic Leptin Is Required For Weight Gain From Circadian Desynchronized Feeding In The Mouse, Deanna M. Arble, Martha H. Vitaterna, Fred W. Turek Sep 2011

Rhythmic Leptin Is Required For Weight Gain From Circadian Desynchronized Feeding In The Mouse, Deanna M. Arble, Martha H. Vitaterna, Fred W. Turek

Biological Sciences Faculty Research and Publications

The neuroendocrine and metabolic effects of leptin have been extensively researched since the discovery, and the later identification, of the leptin gene mutated within the ob/ob mouse. Leptin is required for optimal health in a number of physiological systems (e.g. fertility, bone density, body weight regulation). Despite the extensive leptin literature and many observations of leptin’s cyclical pattern over the 24-hour day, few studies have specifically examined how the circadian rhythm of leptin may be essential to leptin signaling and health. Here we present data indicating that a rhythmic leptin profile (e.g. 1 peak every 24 hours) leads to excessive …


Biotic Resistance Via Granivory: Establishment By Invasive, Naturalized, And Native Asters Reflects Generalist Preference, Dean E. Pearson, Ragan M. Callaway, John L. Maron Sep 2011

Biotic Resistance Via Granivory: Establishment By Invasive, Naturalized, And Native Asters Reflects Generalist Preference, Dean E. Pearson, Ragan M. Callaway, John L. Maron

Biological Sciences Faculty Publications

Escape from specialist natural enemies is frequently invoked to explain exotic plant invasions, but little attention has been paid to how generalist consumers in the recipient range may influence invasion. We examined how seed preferences of the widespread generalist granivore Peromyscus maniculatus related to recruitment of the strongly invasive exotic Centaurea stoebe and several weakly invasive exotics and natives by conducting laboratory feeding trials and seed addition experiments in the field. Laboratory feeding trials showed that P. maniculatus avoided consuming seeds of C. stoebe relative to the 12 other species tested, even when seeds of alternative species were 53–94% smaller …


Physiological Trade-Offs In Self-Maintenance: Plumage Molt And Stress Physiology In Birds, Jamie M. Cornelius, Nicole Perfito, Richard Zann, Creagh W. Breuner, Thomas P. Hahn Aug 2011

Physiological Trade-Offs In Self-Maintenance: Plumage Molt And Stress Physiology In Birds, Jamie M. Cornelius, Nicole Perfito, Richard Zann, Creagh W. Breuner, Thomas P. Hahn

Biological Sciences Faculty Publications

Trade-offs between self-maintenance processes can affect life-history evolution. Integument replacement and the stress response both promote self-maintenance and affect survival in vertebrates. Relationships between the two processes have been studied most extensively in birds, where hormonal stress suppression is down regulated during molt in seasonal species, suggesting a resource-based trade-off between the two processes. The only species found to differ are the rock dove and Eurasian tree sparrow, at least one of which performs a very slow molt that may reduce resource demands during feather growth, permitting investment in the stress response. To test for the presence of a molt–stress …