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Theses/Dissertations

2001

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Full-Text Articles in Life Sciences

From Second Creek To New Pangea: A Multi-Scale Analysis Of Patterns And Trends In Aquatic Biodiversity, Jeffrey Robert Duncan Dec 2001

From Second Creek To New Pangea: A Multi-Scale Analysis Of Patterns And Trends In Aquatic Biodiversity, Jeffrey Robert Duncan

Doctoral Dissertations

The Earth’s freshwater ecosystems are undergoing a period of dramatic change. The simultaneous expansion and contraction of aquatic species’ ranges is leaving an indelible mark on the evolutionary histories of the world’s freshwater species. This dissertation represents a compilation of research efforts that quantify, explain, and propose policy recommendations concerning current trends in aquatic biodiversity. Part II provides an appraisal of the status of the world’s freshwater fishes that asks two primary questions—are all taxonomic groups equally susceptible to extinction, and can we identify a unifying suite of extinction risk factors? Although I concluded, that extinction risk is not randomly …


The Effect Of The Human Papillomavirus E5 Protein On Apoptosis In Human Foreskin Keratinocytes, Kasey Pattan Dec 2001

The Effect Of The Human Papillomavirus E5 Protein On Apoptosis In Human Foreskin Keratinocytes, Kasey Pattan

Electronic Dissertations and Theses

There are over seventy genotypes of Human Papillomaviruses (HPVs), some cause benign warts and others are risk factors for the development of carcinomas of the respiratory and genital tract. Research has proven that the high risk HPV 16 E5 protein in the presence of epidermal growth (EGF) acts as a survival factor resulting in elevated levels of activated epidermal growth factor receptor (EGFR) and activated levels of ERK 1/2 and Akt, two signaling molecules downstream of EGFR, in UVP irradiated human foreskin keratinocytes (HFKs). This leads to the protection of the cells from UVB induced apoptosis. The purpose of this …


Formation Of Multistranded Structures From The Self-Assembly Of G-Rich Dna Oligomers By Various Sequence And Environmental Influences, Bryan D. Vi Dec 2001

Formation Of Multistranded Structures From The Self-Assembly Of G-Rich Dna Oligomers By Various Sequence And Environmental Influences, Bryan D. Vi

Seton Hall University Dissertations and Theses (ETDs)

No abstract provided.


The Influence Of Peat And Inorganic Amendments On Physical Properties Of Sand-Based Rootzones, Freddie C. Waltz Jr. Dec 2001

The Influence Of Peat And Inorganic Amendments On Physical Properties Of Sand-Based Rootzones, Freddie C. Waltz Jr.

All Dissertations

Many golf course putting greens and athletic fields are constructed with a medium consisting of a high sand content. Peat is the most common amendment to rootzone sand (RZS). However, a trend to replace peat with inorganic soil amendments (IOSA), such as calcined clay (CC) and diatomaceous earth (DE), is occurring. Laboratory studies were conducted to evaluate physical and hydraulic properties of rootzone mixtures and a field study investigated the potential of IOSA as a replacement to peat. In laboratory evaluations, amended RZS reduced the bulk density of all mixtures, while saturated hydraulic conductivity (Ksat) for the RZS and mixtures …


Gametogenic Cycles Of Marine Mussels, Mytilus Edulis And Mytilus Trossulus, In Cobscook Bay, Maine, Aaron P. Maloy Dec 2001

Gametogenic Cycles Of Marine Mussels, Mytilus Edulis And Mytilus Trossulus, In Cobscook Bay, Maine, Aaron P. Maloy

Electronic Theses and Dissertations

The Mytilus edulis species complex includes three smooth-shelled blue mussels, M. edulis (Linnaeus 1 75 8), M trossulus (Gould 1 850), and M galloprovincialis (Lamarck 18 19). When any two of theses species occur sympatrically, hybridization and backcrossing of hybrid and parental genotypes is evident. Despite introgression of genes between taxa their genetic integrity is maintained. To test the hypothesis that a temporal variation in species-specific spawning times is the mechanism limiting hybridization and maintaining genetic integrity in a M edulis and M. trossulus hybrid zone in eastern Maine, mussels were sampled on monthly to semi-monthly intervals throughout 2000 from …


Insecticide Reduction Through Precision Foliar Banding With Various Spray Nozzles And Droplet Sizes, Christopher Wayne Smith Dec 2001

Insecticide Reduction Through Precision Foliar Banding With Various Spray Nozzles And Droplet Sizes, Christopher Wayne Smith

Masters Theses

The concept of precision foliar banding application was explored as a practical means of reducing insecticide use. Customfabricated 40-degree flat fan, standard hollow-cone, and twin-orifice nozzles applied over-the-row bands at 94 L ha-1, based on treated area in band, in field and controlled environment tests. Standard broadcast 80-degree hollow-cone and flat fan nozzles served as control treatments.

Field testing under 6 kmh-1 wind conditions produced WSP coverage, as determined by digital image analysis, of 38, 31, 30, 28, and 19 percent for banded 40-degree flat fan, broadcast 80-degree flat fan, banded twin orifice, broadcast twin orifice, and 3-nozzle banded hollow …


Effect Of Monounsaturated Fat Rich Almonds On Hemostatic And Inflammatory Factors In Healthy Adults, Kristianne M. Connell Dec 2001

Effect Of Monounsaturated Fat Rich Almonds On Hemostatic And Inflammatory Factors In Healthy Adults, Kristianne M. Connell

Loma Linda University Electronic Theses, Dissertations & Projects

Background: The frequent consumption of nuts is inversely associated with the incidence of cardiovascular disease. Nuts are known to decrease the risk of cardiovascular disease by reducing serum total and low-density lipoprotein (LDL) cholesterol. Markers of inflammation including C-reactive protein, E-selectin and interleukin-6 have been proposed to be newer risk factors for cardiovascular disease. However, the influence of nuts such as almonds on markers of inflammation and hemostasis that influence cardiovascular disease risk is not currently known.

Objective: The objective of this study was to determine the effect of almond consumption on markers of inflammation and hemostatic factors in healthy …


Enzymatic Deinking Of Flexographic Water-Based Inks, Somporn Chaiarrekij Dec 2001

Enzymatic Deinking Of Flexographic Water-Based Inks, Somporn Chaiarrekij

Masters Theses

Introduction

In recent times, environmental concerns have led to the development of water-based flexographic and rotogravure inks. One of the major concerns for water-based inks is their deinkability. Wash deinking of flexographic water-based ink is much more effective than flotation deinking; however, it has two major disadvantages. It consumes large amounts of water and gives a lower yield than flotation due to the loss of fines and fillers in the effluent (1).


Validation Of A Sun-Exposure Questionnaire For Adolescent Girls, Jennifer L. Cobb Dec 2001

Validation Of A Sun-Exposure Questionnaire For Adolescent Girls, Jennifer L. Cobb

Electronic Theses and Dissertations

Sunlight is a major contributor to an individual's vitamin D status. Determinants of sun exposure have been used in conjunction with dietary data to study the effect of sunlight on bone health of elderly populations. Sun-exposure questionnaires to assess vitamin D status have not been utilized or tested in populations of children in the United States. This is the first questionnaire, used in accordance with vitamin D research, to be tested against an objective measure of sun exposure and to account for diurnal variation in ultraviolet B (UVB) ray strength. The objective of this study was to develop and validate …


Effects Of An Increasing Harbor Seal Population On Changes In Sites Used For Pupping, Nikolina Guldager Dec 2001

Effects Of An Increasing Harbor Seal Population On Changes In Sites Used For Pupping, Nikolina Guldager

Electronic Theses and Dissertations

Aerial survey data from 198 1 to 1997 of an increasing harbor seal (Phoca vitulina concolor) population in Penobscot and Blue Hill bays, Maine, were used to evaluate spatial and temporal patterns of use of pupping sites by mother-pup pairs. Pupping sites refer to haul-out sites where pups were observed during surveys, and are assumed to be used consistently from birth to weaning. Sites with pups were spatially clustered to remove spatial auto-correlation, reduce temporal variability and provide biologically cohesive and independent sample units. Spatial, temporal and habitat analyses were completed for 2 spatial scales: individual sites and …


Detection Of Insulin Receptor, Epidermal Growth Factor Receptor, And Interleukin-6 On Individual Mouse Embryos By Immuno-Polymerase Chain Reaction, Kun Xu Dec 2001

Detection Of Insulin Receptor, Epidermal Growth Factor Receptor, And Interleukin-6 On Individual Mouse Embryos By Immuno-Polymerase Chain Reaction, Kun Xu

Electronic Theses and Dissertations

Three series of experiments were conducted to: 1) optimize the conditions for the production of pUC19 plasmid and of biotinylated pUC19 fragments; 2) optimize the conditions for the production of protein A-streptavidin chimera (chimeric protein); and 3) detect soluble antigens [bovine serum albumin (BSA) and interleukin-6 (IL-6)] and membrane-bound antigens [insulin receptor and epidermal growth factor receptor (EGFr)] of mouse embryos by immuno-polymerase chain reaction (I-PCR). The first experimental series, which included bacterial culture, chimeric protein purification, and chimeric protein functional experiments, was performed to investigate the effects of IPTG (isopropyl-β-D-thiogalactopyranoside) induction time and temperature, bacterial culture medium, and protein …


Characterization Of Biochelators, Membrane Redox Systems, And Quinone Reductases From Wood Degrading Basidiomycetes, Weihong Qi Dec 2001

Characterization Of Biochelators, Membrane Redox Systems, And Quinone Reductases From Wood Degrading Basidiomycetes, Weihong Qi

Electronic Theses and Dissertations

Biodegradation of wood by brown rot fungi is dependent upon a non-enzymatic system involving Fenton chemistry. Iron biochelators with molecular weights lower than 1kD are important components in this process. Phenolate biochelators drive a hydroxyl radical generating Fenton reaction by reducing ferric iron. Biochelators may be mineralized or alternately, in some cases oxidized biochelators may be regenerated via a quinone redox cycle. Electron donors for this postulated regeneration have not been identified. Extracellular cellobiose dehydrogenase has also been found to drive the Fenton reaction by generating ferrous iron and hydrogen peroxide. This research compared the production of biochelators and the …


Study Of Conidia Production And Transmission Of Beauverza Bassiana (Balsamo) Vuill. In Colorado Potato Beetle (Leptinotarsa Decemlineata), Silvia Fernandez Dec 2001

Study Of Conidia Production And Transmission Of Beauverza Bassiana (Balsamo) Vuill. In Colorado Potato Beetle (Leptinotarsa Decemlineata), Silvia Fernandez

Electronic Theses and Dissertations

This work is an investigation of:( 1) mortality of the Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), under different modes of exposure to the pathogen Beauveria bassiana (Bals.) Vuill., (2) host and environmental factors affecting sporulation, production, and viability of B. bassiana conidia from infected cadavers of CPB larvae, and (3) transmission of the disease in CPB populations. The research leads to an improved understanding of the process of transmission of B. bassiana in CPB populations. This may enhance its use as a biological control agent for this pest insect. The highest rate of mortality of CPB larvae (77 percent) …


Evaluating Shade Bias In Insect Trap Catch And Assessing The Short- And Long-Term Impacts Of Herbicide Application In Regenerating Clearcuts On Flowering Plant Communities, Kathryn M. Georgitis Dec 2001

Evaluating Shade Bias In Insect Trap Catch And Assessing The Short- And Long-Term Impacts Of Herbicide Application In Regenerating Clearcuts On Flowering Plant Communities, Kathryn M. Georgitis

Electronic Theses and Dissertations

Regenerating clearcuts are commonly sprayed with a broad-spectrum herbicide, Glyphosate, to suppress regenerating hardwoods that outcompete the more desirable softwood species. Although the direct effects of herbicide application are minimal, the resulting changes in vegetation have raised concern over its indirect effects on wildlife. On the other hand, clearcuts are high in plant diversity, which may provide beneficial resources for Hymenoptera in the clearcut area and the adjacent forest stands. To assess the short- and long-term impacts of herbicide application on insect communities, comparisons between stands of various ages and treatments are necessary. Insect traps provide one efficient method for …


Genomic Organization Of Infectious Salmon Anemia Virus, Trent Rector Dec 2001

Genomic Organization Of Infectious Salmon Anemia Virus, Trent Rector

Electronic Theses and Dissertations

Infectious salmon anemia virus (ISAV) is an emerging pathogen of farmed Atlantic salmon (Salmo salar). The development of an effective ISA virus vaccine is a high priority for salmon producers in the U.S. and elsewhere. The process of developing a recombinant vaccine requires complete genetic characterization of the virus. Toward this end we have cloned, sequenced and determined the organization of the eight segments of single-stranded RNA from ISA virus isolate CCBB. The virus was grown in cell culture and purified by density gradient ultracentrifugation. Viral RNA was isolated from purified ISAV and used in the construction of two different …


The Role Of Water Motion In Algal Reproduction, Richard Gordon Dec 2001

The Role Of Water Motion In Algal Reproduction, Richard Gordon

Electronic Theses and Dissertations

Environmental conditions, such as water motion, can influence fertilization success and spore dispersal in marine algae. Previous studies on fucoid algae showed that gamete release is restricted to, or enhanced by, periods of low water motion. Few other algal taxa have been investigated, however, including species with an alternation of generations. I investigated gamete and spore release in the macroalgae Alaria esculenta and Ulva lactuca, as well as in the diatom Pseudo-nitachia multiseries to determine if water motion is inhibitory or stimulates propagule production and release. I used orbital shakers to simulate water motion; these were interspersed with stationary platforms …


Effects Of A Serine 364 To Proline Mutation Of The Connexin43 Protein In Transgenic Mice, Chia-Ling Nhan-Chang Dec 2001

Effects Of A Serine 364 To Proline Mutation Of The Connexin43 Protein In Transgenic Mice, Chia-Ling Nhan-Chang

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]


Variables Influencing Nest Success Of Eastern Wild Turkeys In Connecticut: Nesting Habitat, Home Range-Scale Fragmentation, And Nest Attentiveness, Shelley M. Spohr Dec 2001

Variables Influencing Nest Success Of Eastern Wild Turkeys In Connecticut: Nesting Habitat, Home Range-Scale Fragmentation, And Nest Attentiveness, Shelley M. Spohr

Electronic Theses and Dissertations

Nest success is the most important demographic parameter influencing rates of population change of eastern wild turkeys (Meleagris gallopavo si1vestris) and many variables operating at multiple spatial and temporal scales may influence whether a nest is successful. Most studies of nest success and survival of turkeys have occurred in forested or agricultural landscapes; variables influencing nest success have not been studied in suburban landscapes. My objectives were to: 1 ) quantify survival and reproductive parameters of eastern wild turkey hens in the suburban environment of southeastern Connecticut and compare results to studies conducted in other northeastern states; 2) …


Antibiotic Resistance: Multi-Drug Profiles And Genetic Determinants., Lashan Denise Taylor Dec 2001

Antibiotic Resistance: Multi-Drug Profiles And Genetic Determinants., Lashan Denise Taylor

Electronic Theses and Dissertations

Antimicrobial susceptibility profiles were assembled for isolates of Moraxella catarrhalis collected from the Mountain Home Veteran's Affairs Medical Center (VAMC) clinical laboratory in Johnson City, Tennessee. The goal of the study was to identify isolates for genetic characterization using comparisons of susceptibility profiles. Isolates of Moraxella catarrhalis collected from July 1984 through 1994 were analyzed for β-lactamase production using a Cefinase disk assay.

A multi-drug profile consisting of 11 β-lactam antibiotics was performed on the 41 M. catarrhalis isolates. Kirby Bauer disk assays were performed for 7 cephalosporin and 4 non-cephalosporin antibiotics.

In summary, 2 observations implicate more complex resistance …


Polycyclic Aromatic Hydrocarbon Degradation By Novel Bacteria Isolated From Burrow Sediments Of Marine Benthic Macrofauna, Wai Ki Chung Dec 2001

Polycyclic Aromatic Hydrocarbon Degradation By Novel Bacteria Isolated From Burrow Sediments Of Marine Benthic Macrofauna, Wai Ki Chung

Electronic Theses and Dissertations

Polycyclic aromatic hydrocarbons (PAH) are significant environmental pollutants and represent a severe health threat. Many cosmopolitan areas including coastal environments are heavily impacted by PAH. This research investigates the isolation of PAH-degrading bacteria from burrow sediment of marine benthic macrofauna and their potential in bioremediation. Macrofaunal burrow sediment is biogeochemically distinct from bulk sediment and has high microbial activities. Samples were collected from a local uncontaminated cove and PAH degradation potential was measured by incubating sediment slurries with exogenous PAH. Burrow sediments from two polychaetes and a mollusc showed significantly higher PAH degradation potential than the bulk sediment. The degradation …


Autoimmunity, Immune Deficiency And Cancer: Multiple Roles Of The Protein Tyrosine Phosphate Shp-1, Melissa J. Joliat Dec 2001

Autoimmunity, Immune Deficiency And Cancer: Multiple Roles Of The Protein Tyrosine Phosphate Shp-1, Melissa J. Joliat

Electronic Theses and Dissertations

One of a large number of mutant mice used in immunological research, the "motheaten" mouse was the first model of a specific protein tyrosine phosphatase deficiency. Mice carrying one of two allelic mutations at the "motheaten" locus have severe systemic autoimmunity and immune dysfunction as a result of mutations in the hematopoietic-cell phosphatase (Hcph) gene, which encodes the protein tyrosine phosphatase SHP-1. Studies using "motheaten" (me/me) and "viable motheaten" (mev/mev) mice have increased the understanding of numerous signaling pathways in immune and hematopoietic cells. A number of studies on SHP-1 function …


Cold-Temperature Adaptation Of Muscle Creatine Kinase From An Antartic Teleost (Chaenocephalus Aceratus), Paul Winnard Jr. Dec 2001

Cold-Temperature Adaptation Of Muscle Creatine Kinase From An Antartic Teleost (Chaenocephalus Aceratus), Paul Winnard Jr.

Electronic Theses and Dissertations

The white muscle of Chuenocephulus aceratus, an Antarctic teleost of the Channicthyidae family, has a compromised glycoiytic capacity and this fish cannot depend on glycolysis for rapid ATP generation For C. aceratus, creatine kinase (CK) and phosphocreatine (PCr) reserves comprise the metabolic pathway that may supplement and overcome this deficiency in energy transduction. Two conditions, low glycolytic capacity and evolution in a chronically cold habitat (-1.86°C), give us reason to believe that C. aceratus muscle CK (MMCK) has been subjected to strong selective pressure. Thus, the hypothesis of this thesis is that MMCK fiom C. aceratus white muscle …


Iron Acquisition In Rhodococcus Erythrolpolis: The Isolation Of Mutant(S) That Do Not Produce A Siderophore., Jaishree M. Vellore Dec 2001

Iron Acquisition In Rhodococcus Erythrolpolis: The Isolation Of Mutant(S) That Do Not Produce A Siderophore., Jaishree M. Vellore

Electronic Theses and Dissertations

Rhodococcus, a soil bacterium, displays a diverse range of metabolic capabilities with a number of potential practical applications. To exploit the metabolic potential of Rhodococcus, their basic physiology, genetics, and especially the acquisition of essential nutrients like iron, must be understood.

R. erythropolis strain IGTS8 releases a small compound called a siderophore, that scavenges ferric iron from the environment. To learn more about the genetic control of iron acquisition, mutant(s) defective in siderophore production were isolated. Mutants were generated, by inserting a mutagenic plasmid, pJCS506, into the bacterial cell using electroporation. The plasmid, which cannot replicate in these …


Examining The Effects Of Deer Antler Velvet Supplementation On Muscular Strength, Performance, And Markers Of Delayed Onset Muscle Soreness., Robyn Suzanne Percival Dec 2001

Examining The Effects Of Deer Antler Velvet Supplementation On Muscular Strength, Performance, And Markers Of Delayed Onset Muscle Soreness., Robyn Suzanne Percival

Electronic Theses and Dissertations

Purpose: To examine the effects of deer antler velvet on muscular strength, performance, and markers of delayed onset muscle soreness following a 10-week resistance training period.

Participants: 16 resistance-trained males (18-35) volunteered.

Measures: DEXA, 1-RM, a power test, and a 70% performance trial were measured. Creatine kinase and self-reported soreness levels were measured following an eccentric trial.

Results: No pre-experimental significant differences existed between the groups for any of the variables measured. There were no significant differences between the groups regarding body composition, strength, muscular performance, or improvements in creatine kinase and soreness levels from pre to post-intervention. Both groups …


Comparison Of Black And White Elderly Women On Muscle Mass Bone Mineral Density And Balance., Tyanez Jones Dec 2001

Comparison Of Black And White Elderly Women On Muscle Mass Bone Mineral Density And Balance., Tyanez Jones

Electronic Theses and Dissertations

Few studies have compared balance between aging black (BW) and white women (WW) and examined its relationship to muscle mass and bone mineral density (BMD). Nineteen BW and 56 WW between 60-91 years participated. Upper and lower body strength, body composition, BMD, volitional and non-volitional control of dynamic balance, and physical activity ratings were assessed. There were no differences in strength between the groups. A trend was reported for total body BMD (p=0.07). WW exhibited better control of rapid volitional movements, in the limits of stability and rhythmic weight shift tests. The relationships of strength and muscle mass to BMD …


Intra- And Inter-Person Variability In Glycemic Responsiveness, Cassandra S. Baldwin Dec 2001

Intra- And Inter-Person Variability In Glycemic Responsiveness, Cassandra S. Baldwin

Honors Theses

No abstract provided.


Comparative Anatomy Of The Lower Respiratory Tract Of The Gray Short-Tailed Opossum (Monodelphis Domestica) And North American Opossum (Didelphis Virginiana), Lee Anne Cope Dec 2001

Comparative Anatomy Of The Lower Respiratory Tract Of The Gray Short-Tailed Opossum (Monodelphis Domestica) And North American Opossum (Didelphis Virginiana), Lee Anne Cope

Doctoral Dissertations

The present study describes the lower respiratory tract anatomy of the gray short-tailed opossum (Monodelphis domestica) and North American opossum (Didelphis virginiana). The trachea of the gray short-tailed opossum consists of 25 c-shaped tracheal cartilages. The trachea of the North American opossum consists of 28 c-shaped cartilages. The right lung of both species is separated into cranial, middle, caudal and accessory lobes by interlobar fissures. The left lung consists of unseparated cranial and caudal lobes. The right and left pulmonary arteries of the gray short-tailed and North American opossums divide into pulmonary lobar arteries. The pulmonary lobar veins join to …


Determination Of 17Β-Estradiol And Estrone Concentrations In Runoff And Topsoil From Plots Receiving Dairy Manure, Angel Renea Peters Dyer Dec 2001

Determination Of 17Β-Estradiol And Estrone Concentrations In Runoff And Topsoil From Plots Receiving Dairy Manure, Angel Renea Peters Dyer

Masters Theses

Because of increasing concern about estrogenic compounds in animal wastes, the objective of this research was to measure 17β-estradiol and estrone concentrations in runoff and soil from plots fertilized with liquid dairy waste. Nine plots were established at The University of Tennessee Dairy Experiment Station located at Lewisburg, Tennessee, and dairy manure was applied to six of the nine plots in November, 2000. Three of the plots received manure at a rate sufficient to meet the nitrogen (N) requirement for winter wheat; three received manure at a rate sufficient to meet the phosphorus (P) requirement for winter wheat, and three …


Cost Comparisons Considering Herd Size, Transport Distance, And Nitrogen Versus Phosphorus Application Rates For Liquid Dairy Waste Transport And Application Systems, Adam Shane Daugherty Dec 2001

Cost Comparisons Considering Herd Size, Transport Distance, And Nitrogen Versus Phosphorus Application Rates For Liquid Dairy Waste Transport And Application Systems, Adam Shane Daugherty

Masters Theses

A cost estimation model was developed that compares the economics associated with different animal waste transport and application systems used by confined animal operations. The model was constructed from data collected from individual farmers, equipment manufacturers, and gleaned from waste management system manuals. The model was developed to provide animal waste transport and application cost estimates for both liquid and dry waste management systems. The model was developed in Microsoft Excel. Using facility specific information, the model estimates the costs associated with various components of manure transport and application systems. Specifically, the model enables comparisons of capital costs, annual operating …


Hamp Domain And Signaling Mechanism Of The Aer Protein, Qinhong Ma Dec 2001

Hamp Domain And Signaling Mechanism Of The Aer Protein, Qinhong Ma

Loma Linda University Electronic Theses, Dissertations & Projects

Escherichia coli utilizes the Aer protein to sense changes in the intracellular energy level and guide the bacteria to a niche where the cellular energy level is optimal. Aer contains a PAS sensory domain and an FI fragment in the N terminus and a chemotaxis signaling domain in the C terminus, separated by a putative transmembrane region. In this dissertation, I report that the linker region of Aer (residues 205-265), which joins the transmembrane region to the signaling domain, is a conserved signal transduction module in numerous methyl-accepting chemoreceptors, histidine kinases, adenylyl cyclases, and other sensory proteins in all three …