Effect of Colchicine on Neuronal Excitabilty

Effect of Colchicine on Neuronal Excitabilty

Date: August 1978
Creator: Okafo, Ngozi
Description: The abundance of microtubules in receptive dendrites suggests they may function in sensory transduction. Responses of frog muscle spindle receptors and joint receptors is inhibited within 25 minutes by 50 mM colchicine, a microtubuledisrupting agent. The inhibition is reversible upon removal of colchicine, and the time course of recovery is comparable to that of inhibition. Frog olfactory responses are briefly inhibited by washing the olfactory mucosa with perfusion fluid. Colchicine accentuates the inhibition and substantially retards the rate of recovery in a dose-dependent fashion. Colchicine does not affect axonal conduction, nor the oxygen uptake of isolated crab or frog leg nerves. The inhibitory action of colchicine is therefore an effect on the electrical excitability of the receptive dendrites or soma, and not an effect on axonal conduction.
Contributing Partner: UNT Libraries
Factor Analysis of the Clinical Scales on the Luria-Nebraska Neuropsychological Battery, Form II

Factor Analysis of the Clinical Scales on the Luria-Nebraska Neuropsychological Battery, Form II

Date: August 1987
Creator: Von Seggern, Heather Beth
Description: The Luria-Nebraska Neuropsychological Battery (LNNB) was published in 1980 as an attempt to provide clinicians with a standardized version of the neuropsychological assessment and diagnostic procedures proposed by A. R. Luria and A, L. Christensen. Research on the LNNB included a series of factor analyses for each of eleven clinical scales. The analyses were completed on the combined scores obtained from a sample of normal, brain-damaged, and psychiatric populations. A second version of the LNNB was published in 1985 as a largely parallel version of Form I, but included changes in stimulus materials, administration procedures, and scoring procedures. The present study completed factor analyses on same eleven clinical scales using data generated with the newer LNNB Form II. The statistical procedures and criteria employed in the present investigation were identical to those used earlier on Form I to allow for comparisons between the two resulting sets of factor structures. The patient populations were different, however, in that all subjects in the current study were receiving inpatient care in a private psychiatric hospital which specializes in long-term treatment. Despite the changes in materials and procedures and the difference in subject parameters, the factors identified in the present investigation are similar to ...
Contributing Partner: UNT Libraries
MMPI-2 Patterns of Adults with Attention-Deficit Hyperactivity Disorder

MMPI-2 Patterns of Adults with Attention-Deficit Hyperactivity Disorder

Date: August 1998
Creator: Campbell, Catherine Elaine
Description: Recent literature suggests that not only does Attention-deficit Hyperactivity Disorder (ADHD/ADD) persist into adulthood, but it can also be accompanied by personality characteristics which cause emotional difficulties. In fact, adults diagnosed with ADHD can present with a profusion of difficulties. Several constructs appear to accumulate dynamically throughout development to place the adult with ADHD at risk for multiple emotional problems. These interwoven influences include familial characteristics, childhood emotional and academic difficulties, and inadequate coping skills to respond to adulthood pressures. This document, first, describes a developmental model for conceptualizing negative trajectories leading to nonadaptive coping and psychopathology and identifies personality factors of adults diagnosed with ADHD. This model provides clinicians and researchers with a better understanding of the complexity and challenges of adulthood ADHD in order to aid in diagnosis, treatment, and prevention. The purpose of this study is to examine personality factors common to adults diagnosed with ADHD and compares these characteristics with a group of adults diagnosed with a depressive disorder. Adults responding to a community advertisement who provided documentation of the diagnosis of Attention-deficit Hyperactivity Disorder were administered the MMPI-2. This ADHD group was compared with MMPI-2 profiles of a group of adults diagnosed with Major Depressive ...
Contributing Partner: UNT Libraries
The Effects of Hypothermia on the Release of Cardiac Enzymes

The Effects of Hypothermia on the Release of Cardiac Enzymes

Date: August 1977
Creator: Strawn, William B.
Description: The myocardium is known to release CPK, LDH1 , and GOT in response to ischemia as a result of myocardial infarction. This study was designed to induce the release of cardiac enzymes without adversely effecting the myocardium by perfusion hypothermia, thereby suggesting that these enzymes are not as specific in the diagnosis of myocardial infarction as once thought. Hypothermia was by in vivo perfusion of the left anterior descending coronary artery. Enzyme activity was measured from sera samples spectrophotometrically and electrophoretically. Significant CPK and LDH1 increases were observed in animals perfused between 25 and 19 C. These results indicate that, while heart function remained unchanged, an alteration occurred in the membrane integrity of the myocardial cells.
Contributing Partner: UNT Libraries
Neuroregulation and Myosin Light Chain Phosphorylation in Ascaris Suum Obliquely Striated Skeletal Muscle

Neuroregulation and Myosin Light Chain Phosphorylation in Ascaris Suum Obliquely Striated Skeletal Muscle

Date: August 1985
Creator: Martin, Rex E. (Rex Edward)
Description: Extraction and quantitation of myosin light chain two coupled with myograph recordings from Ascaris muscle perfused with calmodulin inhibitors and neurotransmitters in conjunction with their respective agonists and antagonists have been used to establish the regulation of contraction in this muscle. Densitometric tracings of isolectric focusing gels separating the regulatory light chain were used to quantitate phosphorylation in resting, contracted and flaccid muscle. These studies indicated that inhibitory neurostimulation is mediated by a true GABA receptor. Myosin-mediated contraction is responsible for maintaining the level of tension observed in resting actin-mediated muscle. Actin-mediated contraction is responsible for the rapid rise in tension following excitatory stimuli. Both systems function simultaneously and are independant.
Contributing Partner: UNT Libraries
Brain Activity in Rats Exposed to Short-Term External Electrical Fields

Brain Activity in Rats Exposed to Short-Term External Electrical Fields

Date: May 1985
Creator: Hines, Gregory M. (Gregory Manuel)
Description: The effects of external electric fields (EEF) on brain activity in anesthetized rats were studied. The field strengths used, 9 kV/m and 5 kV/m, both D.C. and A.C. (60Hz) were in the range of those measured beneath current overhead transmission lines. Brain activity was monitored from surface electrodes and from electrodes stereotaxically implanted in the posterior-lateral portion of the hypothalamus. It was found that 9 kV/m and 5 kV/m EEF's both D.C. and A.C. brought about statistically significant changes in hypothalamic activity, however, the effects were bi-directional, (i.e. increases and decreases). Only seven of the 60 animals exposed showed changes in the EEG recorded with surface electrodes. The data clearly indicate that (1) anesthetized animals do respond to a change in the external electric field around them, (2) the hypothalamus may contain special electro-receptors that, in turn, may alter various other physiological processes, and (3) the data indicates the need for further research to help government agencies to establish more adequate safety guidelines.
Contributing Partner: UNT Libraries
The Effects of Oat Fiber and Corn Bran on Blood Serum Cholesterol and Triglyceride Levels

The Effects of Oat Fiber and Corn Bran on Blood Serum Cholesterol and Triglyceride Levels

Date: August 1985
Creator: Broeder, Craig E. (Craig Elliot)
Description: Forty Sprague Dawley rats were randomly placed in five groups with eight rats per group. Each group varied in dietary composition for fiber type and carbohydrate source. Groups one and two received oat fiber and either sucrose or corn starch as the carbohydrate source. Groups three and four received corn bran as the fiber source and either sucrose or corn starch as the carbohydrate source. Group five (considered the control group), received Purina standard rat chow. Analysis of variance showed only significant differences for food intake, and the control group had a significantly higher food intake. Weight gain, serum cholesterol and triglyceride levels showed no significant differences.
Contributing Partner: UNT Libraries
Effect of Calcium Channel Antagonists and Other Agents on Olfactory Reception

Effect of Calcium Channel Antagonists and Other Agents on Olfactory Reception

Date: August 1985
Creator: Rosick, Edward R. (Edward Rudolph)
Description: The role of Ca++ in olfactory responses was investigated with inorganic and organic calcium channel antagonists. Electrophysiological responses to odorants were recorded from frog olfactory mucosa before and after aerosol application of different agents. Electroolfactogram responses were blocked by certain inorganic ions with the order of effectiveness Zn++ >Ln+++>Cd++>Ca++>Co++>Sr++>Mg++. Ba++ potentiated olfactory responses, and is known to potentiate calcium channel-mediated responses in other tissues. Certain local anesthetics which are thought to act through calcium channel blockade were inhibitory to olfactory responses, with the order of effectiveness being dibucaine>tetracaine>procaine. These data support the idea that Ca++ is involved in olfaction, perhaps acting as a current carrier and/or a second messenger. Preliminary experiments on channel localization were performed using a silicon-labeled amine. Attempts to localize the silicon label were inconclusive, although silicon was detected in the olfactory tissue.
Contributing Partner: UNT Libraries
ReSource, Volume 7, Number 1, Fall 1990

ReSource, Volume 7, Number 1, Fall 1990

Date: 1990
Creator: University of North Texas
Description: ReSource magazine includes articles and notes about research at University of North Texas in various academic fields.
Contributing Partner: University Relations, Communications & Marketing department for UNT
Microsatellite-based genetic profiling for the management of wild and captive flamingo populations.

Microsatellite-based genetic profiling for the management of wild and captive flamingo populations.

Date: December 2005
Creator: Kapil, Richa
Description: Flamingo species generate tremendous interest whether they are small captive groups or wild populations numbering in the thousands. Genetic pedigrees are invaluable for maintaining maximum genetic diversity in captive, as well as wild, populations. However, presently there is a general lack of genetic data for flamingo populations. Microsatellites are loci composed of 2-6 base pair tandem repeats, scattered throughout higher eukaryotic genomes, often exhibiting high levels of polymorphism and heterozygosity. These loci are thus important genetic markers for identity, parentage and population studies. Here, six microsatellite loci were isolated from a microsatellite-enriched Caribbean flamingo partial genomic library. Two are compound complex repeats and four are perfect trinucleotide repeats. Each locus was amplified from Caribbean, African greater, Chilean and lesser flamingo genomic DNAs. Heterozygosity frequencies were calculated for Caribbean (range 0.12-0.90) and African greater flamingos (range 0.23-0.94) loci. All six microsatellite loci were found to be in Hardy-Weinberg equilibrium and linkage disequilibrium analyses did not suggest linkage for any pair of two greater flamingo subspecies (African and Caribbean) loci. At least five of the loci also exhibit polymorphism in Chilean and lesser flamingos, but due to small sample numbers, relevant allele/heterozygosity frequency calculations could not be estimated. Nucleotide sequence comparisons of ...
Contributing Partner: UNT Libraries
Impaired virulence factor production in a dihydroorotate dehydrogenase mutant (pyrD) of  Pseudomonas aeruginosa.

Impaired virulence factor production in a dihydroorotate dehydrogenase mutant (pyrD) of Pseudomonas aeruginosa.

Date: December 2005
Creator: Ralli, Pooja
Description: Previous research in our laboratory showed that when knockout mutations were created in the pyrB and pyrC genes of the pyrimidine pathway in Pseudomonas aeruginosa, not only were the resultant mutants auxotrophic for pyrimidines but they were also impaired in virulence factor production. Such a correlation had not been previously reported for P. aeruginosa, a ubiquitous opportunistic pathogen in humans. In an earlier study it was reported that mutants blocked in one of the first three enzymes of the pyrimidine pathway in the non-pathogenic strain P. putida M produced no pyoverdin pigment while mutants blocked in the later steps produced copious amounts of pigment, just like the wild type. This study probed for the same connection between pyrimidine auxotrophy and pigment production applied in P. aeruginosa. To that end a knockout mutation was created in pyrD, the fourth step in the pyrimidine pathway which encodes dihydroorotate dehydrogenase. The resulting mutant required pyrimidines for growth but produced wild type pigment levels. Since the pigment pyoverdin is a siderophore it may also be considered a virulence factor, other virulence factors were quantified in the mutant. These included casein protease, hemolysin, elastase, swimming, swarming and twitching motility, and iron binding capacity. In all ...
Contributing Partner: UNT Libraries
Construction of a  Pseudomonas aeruginosa Dihydroorotase Mutant and the Discovery of a Novel Link between Pyrimidine Biosynthetic Intermediates and the Ability to Produce Virulence Factors

Construction of a Pseudomonas aeruginosa Dihydroorotase Mutant and the Discovery of a Novel Link between Pyrimidine Biosynthetic Intermediates and the Ability to Produce Virulence Factors

Date: August 2003
Creator: Brichta, Dayna Michelle
Description: The ability to synthesize pyrimidine nucleotides is essential for most organisms. Pyrimidines are required for RNA and DNA synthesis, as well as cell wall synthesis and the metabolism of certain carbohydrates. Recent findings, however, indicate that the pyrimidine biosynthetic pathway and its intermediates maybe more important for bacterial metabolism than originally thought. Maksimova et al., 1994, reported that a P. putida M, pyrimidine auxotroph in the third step of the pathway, dihydroorotase (DHOase), failed to produce the siderophore pyoverdin. We created a PAO1 DHOase pyrimidine auxotroph to determine if this was also true for P. aeruginosa. Creation of this mutant was a two-step process, as P. aeruginosa has two pyrC genes (pyrC and pyrC2), both of which encode active DHOase enzymes. The pyrC gene was inactivated by gene replacement with a truncated form of the gene. Next, the pyrC2 gene was insertionally inactivated with the aacC1 gentamicin resistance gene, isolated from pCGMW. The resulting pyrimidine auxotroph produced significantly less pyoverdin than did the wild type. In addition, the mutant produced 40% less of the phenazine antibiotic, pyocyanin, than did the wild type. As both of these compounds have been reported to be vital to the virulence response of P. aeruginosa, ...
Contributing Partner: UNT Libraries
The Confederate Pension Systems in Texas, Georgia, and Virginia: The Programs and the People

The Confederate Pension Systems in Texas, Georgia, and Virginia: The Programs and the People

Access: Use of this item is restricted to the UNT Community.
Date: December 2004
Creator: Wilson, Mary L.
Description: The United States government began paying pensions to disabled Union veterans before the Civil War ended in April 1865. By 1890 its pension programs included any Union veteran who had fought in the Civil War, regardless of his financial means, as well as surviving family members, including mothers, fathers, brothers, and sisters. Union veterans did not hesitate to "wave the bloody shirt" in their attempts to liberalize pension laws. Pension programs for Confederate veterans were much slower to develop. Lacking any higher organization, each southern state assumed the responsibility of caring for disabled and/or indigent Confederate veterans and widows. Texas began paying Confederate pensions in 1899, Georgia in 1888 and Virginia in 1889. Unlike Texas, Georgia and Virginia provided artificial limbs for their veterans long before they started paying pensions. At the time of his enlistment in the 1860s, the typical future pensioner was twenty-five years of age, and fewer than half were married heads of households. Very few could be considered wealthy and most were employed in agriculture. The pensioners of Georgia, Texas, and Virginia were remarkably similar, although there were some differences in nativity and marital status. They were all elderly and needy by the time they asked ...
Contributing Partner: UNT Libraries
Influence of Cholesterol Import on  Aspergillus fumigatus Growth and Antifungal Suscepibility

Influence of Cholesterol Import on Aspergillus fumigatus Growth and Antifungal Suscepibility

Access: Use of this item is restricted to the UNT Community.
Date: December 2003
Creator: Hassan, Saad A.
Description: Invasive pulmonary aspergillosis is a life-threatening fungal infection commonly observed in immunocompromised patients and has a mortality rate approaching 100% once the disease is disseminated. Aspergillus fumigatus is the most common pathogen. Early diagnosis improves the prognosis but is very difficult since most signs and symptoms are nonspecific. Antifungal therapy, usually based on sterol biosynthesis inhibitors, is also of limited efficacy. In my attempts to discover a diagnostic sterol marker for aspergillosis, I observed that A. fumigatus incorporates large amounts of cholesterol from serum-containing medium. This observation suggested the hypothesis that exogenous cholesterol from the host can be imported by A. fumigatus and used as a substitute for ergosterol in the cell membrane. This proposed mechanism would reduce the efficacy of antifungal drugs that act as sterol biosynthesis inhibitors. Experiments to test this hypothesis were designed to determine the effects of serum-free and serum-containing medium on growth of A. fumigatus in the presence and absence of azole antifungal agents. The results showed a marked increase in growth in the presence of human serum. Cultures in media containing cholesterol but no serum also showed enhanced growth, a result indicating that a non-cholesterol component of serum is not primarily responsible for the ...
Contributing Partner: UNT Libraries
Regulation of pyrimidine biosynthesis and virulence factor production in wild type, Pyr- and Crc- mutants in Pseudomonas aeruginosa.

Regulation of pyrimidine biosynthesis and virulence factor production in wild type, Pyr- and Crc- mutants in Pseudomonas aeruginosa.

Date: May 2006
Creator: Asfour, Hani
Description: Previous research in our laboratory established that pyrB, pyrC or pyrD knock-out mutants in Pseudomonas aeruginosa required pyrimidines for growth. Each mutant was also discovered to be defective in the production of virulence factors. Moreover, the addition of exogenous uracil did not restore the mutant to wild type virulence levels. In an earlier study using non-pathogenic P. putida, mutants blocked in one of the first three enzymes of the pyrimidine pathway produced no pyoverdine pigment while mutants blocked in the fourth, fifth or sixth steps produced copious quantities of pigment, just like wild type P. putida. The present study explored the correlation between pyrimidine auxotrophy and pigment production in P. aeruginosa. Since the pigment pyoverdine is a siderophore it may also be considered a virulence factor. Other virulence factors tested included casein protease, elastase, hemolysin, swimming, swarming and twitching motilities, and iron binding capacity. In all cases, these virulence factors were significantly decreased in the pyrB, pyrC or pyrD mutants and even in the presence of uracil did not attain wild type levels. In order to complete this comprehensive study, pyrimidine mutants blocked in the fifth (pyrE) and sixth (pyrF) steps of the biosynthetic pathway were examined in P. aeruginosa. ...
Contributing Partner: UNT Libraries
Isolation and Characterization of Polymorphic Loci from the Caribbean Flamingo (Phoenicopterus ruber ruber): New Tools for Wildlife Management

Isolation and Characterization of Polymorphic Loci from the Caribbean Flamingo (Phoenicopterus ruber ruber): New Tools for Wildlife Management

Access: Use of this item is restricted to the UNT Community.
Date: December 2005
Creator: Preston, E. Lynn
Description: Methods to determine genetic diversity and relatedness within populations are essential tools for proper wildlife management. Today the approach of choice is polymerase chain reaction-based microsatellite analysis. Seven new polymorphic loci were isolated from a microsatellite-enriched Caribbean flamingo genomic library and used to characterize survey populations of Caribbean and African greater flamingos. In addition, four of these loci were used to verify parentage relationships within a captive-breeding population of African greater flamingos. Parentage predictions based upon gamekeeper observations of breeding and nesting did not always agree with genetic-based parentage analyses of the nine suggested family groups. Four family groups were supported (groups I, II, III and VI) by there results. However, an analysis of the remaining five suggested groups, with a total of eight offspring/dam and eight offspring/sire suggested relationships, yielded seven exclusions of the suggested dam and six exclusions of the suggested sire. This put the overall suggested dam exclusion rate at 35% and exclusion rate for suggested sires at 29%. Although the keeper observation data for our family groups must be considered a variable of concern at this time, these findings are certainly suggestive that more carefully controlled studies may reveal that flamingos are not monogamous as long ...
Contributing Partner: UNT Libraries
Pyrimidine Enzyme Specific Activity at Four Different Phases of Growth in Minimal and Rich Media, and Concomitant Virulence Factors Evaluation in Pseudomonas aeruginosa

Pyrimidine Enzyme Specific Activity at Four Different Phases of Growth in Minimal and Rich Media, and Concomitant Virulence Factors Evaluation in Pseudomonas aeruginosa

Access: Use of this item is restricted to the UNT Community.
Date: December 2005
Creator: Azad, Kamran Nikkhah
Description: Pseudomonas aeruginosa is a Gram-negative rod, aerobic, non-fermenting, oxidase positive, pigment producing, and nutritionally versatile bacterium. Infections by P. aeruginosa are the most important cause of morbidity and mortality in immunocompromised patients, given virulence factor production that suppresses antibiotic therapy and promotes persistent infection. This research is the first comprehensive report of the pyrimidine biosynthetic pathway for all phases of growth in minimal and rich media coupled with the evaluation of virulence factor production of P. aeruginosa in comparison to four other bacterial species (Pseudomonas putida, Pseudomonas fluorescens, Burkholderia cepacia, and Escherichia coli wild-type strains). Cellular growth and passing genetic information to the next generation depend on the synthesis of purines and pyrimidines, the precursors of DNA and RNA. The pyrimidine biosynthetic pathway is essential and found in most organisms, with the exception of a few parasites that depend upon the pyrimidine salvage pathway for growth. Both the pyrimidine biosynthetic and salvage enzymes are targets for chemotherapeutic agents. In our laboratory, research on pyrimidine auxotrophic mutants showed the role of the pyrimidine biosynthetic pathway and its intermediates on P. aeruginosa metabolism and impaired virulence factors production. The present research shows that pyrimidine enzymes are active in all phases of growth, ...
Contributing Partner: UNT Libraries
Control, Commitment, and Challenge: Relationships to Stress, Illness, and Gender

Control, Commitment, and Challenge: Relationships to Stress, Illness, and Gender

Date: May 1992
Creator: Embry, Judy K.
Description: Male and female college students were administered scales assessing their daily hassles, negative life events, control, commitment, challenge, psychological symptomatology, psychological distress, and physical symptomatology. Stepwise multiple regression analyses showed that control, commitment, and challenge act in an additive (rather than multiplicative) manner in relation to psychological and physical outcome measures.
Contributing Partner: UNT Libraries
Brief Imagery Training : Effects on Psychological, Physiological and Neuroendocrinological Measures of Stress and Pain

Brief Imagery Training : Effects on Psychological, Physiological and Neuroendocrinological Measures of Stress and Pain

Date: August 1992
Creator: Osborne, Connie M. Brajkovich (Connie Marie Brajkovich)
Description: The present study investigated the influence of a brief, intensive biofeedback-assisted imagery training regimen on psychological, physiological and neuroendocrinological measures of pain and stress in injury related chronic pain patients. The subjects were 36 patients (myelography examcandidates) who were assigned to the imagery or wait-list control group by order of referral presentation and to formulate equivalent groups.
Contributing Partner: UNT Libraries
Pyrimidine Metabolism in Rhizobium: Physiological Aspects of Pyrimidine Salvage

Pyrimidine Metabolism in Rhizobium: Physiological Aspects of Pyrimidine Salvage

Date: December 1989
Creator: Ibrahim, Mohamed M.
Description: The objective of this research was to study the pyrimidine salvage pathways of Rhizobium. Three approaches were used to define the pyrimidine salvage pathways operative in two species of Rhizobium, R. meliloti and R. leguminosarum . The first approach was to ascertain the pyrimidine bases and nucleosides that could satisfy the pyrimidine requirement of pyrimidine auxotrophs. Uracil, cytosine, uridine or cytidine all satisfied the absolute pyrimidine requirement. The second approach was to select for mutants resistant to 5-fluoropyrimidine analogues which block known steps in the interconversion of the pyrimidine bases and nucleosides. Mutants resistant to 5-fluorouracil lacked the enzyme uracil phosphoribosyltransferase (upp ) and could no longer use uracil to satisfy their pyrimidine requirement. Mutants resistant to 5-fluorocytosine, while remaining sensitive to 5- fluorouracil, lacked cytosine deaminase (cod) and thus could no longer use cytosine to satisfy their pyrimidine auxotrophy. The third approach used a reversed phase HPLC column to identify the products that accumulated when cytidine, uridine or cytosine was incubated with cell extracts of wild type and analogue resistant mutants of Rhizobium. When cytidine was incubated with cell extracts of Rhizobium wild type, uridine, uracil and cytosine were produced. This Indicated that Rhizobium had an active cytidine deaminase ...
Contributing Partner: UNT Libraries
Ethical Reasoning Among Baccalaureate Female Nursing Students

Ethical Reasoning Among Baccalaureate Female Nursing Students

Date: August 1989
Creator: Swanson, Jacqueline V. (Jacqueline Viola)
Description: The focus for this study was ethical reasoning among baccalaureate female nursing students. This descriptive and correlational study examined the ethical reasoning of freshmen and senior students at a large southwestern university for women. The research instrument used was the Defining Issues Test developed by Rest. The senior nursing students differed significantly (p < ,05) from the freshmen nursing students in ethical reasoning. However, nursing majors did not differ significantly from the non-nursing majors. A multiple regression analysis was performed that identified two factors associated with ethical reasoning (viz., age and GPA), The correlation coefficients were r= .377 for age and P_ score and r= .315 for GPA and P score. Older students were found to be significantly more advanced in ethical reasoning than were younger students. Students with higher GPAs used principled reasoning significantly more often than did students with lower GPAs. Of interest are the findings related to demographic characteristics, ethnicity, and religious preference. The sample was predominantly white, but a significant difference in use of principled reasoning between whites and non-whites was found. In the sample, whites used ethical reasoning more often than did non-whites. The students in the sample who labeled themselves as Baptists were significantly ...
Contributing Partner: UNT Libraries
Frontier Defense in Texas: 1861-1865

Frontier Defense in Texas: 1861-1865

Date: December 1987
Creator: Smith, David Paul, 1949-
Description: The Texas Ranger tradition of over twenty-five years of frontier defense influenced the methods by which Texans provided for frontier defense, 1861-1865. The elements that guarded the Texas frontier during the war combined organizational policies that characterized previous Texas military experience and held the frontier together in marked contrast to its rapid collapse at the Confederacy's end. The first attempt to guard the Indian frontier during the Civil War was by the Texas Mounted Rifles, a regiment patterned after the Rangers, who replaced the United States troops forced out of the state by the Confederates. By the spring of 1862 the Frontier Regiment, a unit funded at state expense, replaced the Texas Mounted Rifles and assumed responsibility for frontier defense during 1862 and 1863. By mid-1863 the question of frontier defense for Texas was not so clearly defined as in the war's early days. Then, the Indian threat was the only responsibility, but the magnitude of Civil War widened the scope of frontier protection. From late 1863 until the war's end, frontier defense went hand in hand with protecting frontier Texans from a foe as deadly as Indians—themselves. The massed bands of deserters, Union sympathizers, and criminals that accumulated on ...
Contributing Partner: UNT Libraries
An Analysis of Respiratory Mechanisms Controlling Exercise Hyperpnea During Cycle Ergometry Conducted at Selected Workloads and Pedal Frequencies

An Analysis of Respiratory Mechanisms Controlling Exercise Hyperpnea During Cycle Ergometry Conducted at Selected Workloads and Pedal Frequencies

Date: December 1986
Creator: Wise, Charles Hamilton
Description: Respiratory and metabolic patterns in response to variations in exercise workload (WL) and pedal frequency (RPM) were examined in 10 healthy males. Each subject performed WLs of low (L), moderate (M) and high (H) intensity, equivalent to 25%, 50% and 75% V02 m a x at 7 pedal frequencies (40, 50, 60, 70, 80, 90 and 100 RPM). ANOVA ( 3 X 7 design) indicated that WL and RPM had independent and significant effects on all respiratory and metabolic measures; i.e., the greater the WL and RPM, the higher the HR, V02, VC02, Ve, Fb, Vt, Vt/Ti, Vt/Te and Ti/TtQt and the lower the Ti and Te. However, analysis of the interaction effect revealed different response patterns for Fb, Vt, Ti, Vt/Ti, Vt/Te and Ve among the WLs. During L-WL, increases in RPM produced increases in Ve which were due to progressive increases in both Fb and Vt. However, during M-WL and H-WL, increases in RPM produced increases in Ve which were accomplished by a constant Vt and a progressive increase in Fb. My findings suggest that during low WLs, the signal for Vt is dependent on rate of contraction, while during M-WL and H-WL, the signal for Vt appears ...
Contributing Partner: UNT Libraries
Roles of Calcium Ions and Cyclic AMP in Olfactory Transduction

Roles of Calcium Ions and Cyclic AMP in Olfactory Transduction

Date: December 1986
Creator: Winegar, Bruce D. (Bruce David)
Description: The roles of Ca2 + and cAMP in olfactory transduction were explored using agents which affect calcium channels and second messenger systems. These agents were applied at certain calculated final concentrations onto olfactory epithelia of urethane-anesthetized frogs (Sana PiPlens) by two-sec aerosol spray. During extracellular recording, saturated vapors of isoamyl acetate were delivered every 100 sec in 0.3 sec pulses to produce an electroolfactogram (EOG). Inorganic cations that block inward calcium currents inhibit EOG responses with the following rank order: (La3+) > (Zn2+, Cd2+) > (Al3+, Ca2+, Sr2+) > (Co2+). Application of 7.5 mM La3+ eradicates ÂŁ0G's, while Ba2+ (which can carry more current that Ca2+) initially produces significant enhancement (F=43.04, p<0.001, df=19). Magnesium ion has no effect on EOG's at 7.5 mM, while 1.5 X 10"4M Ca2+ is significantly inhibitory (F=5.74; p=0.0355; df=12). Control aerosol sprays of distilled water depress EOG's by an average of 5%. The organic calcium channel antagonists diltiazem and verapamil inhibit EOG's by 17% and 36X, respectively, at a concentration of 1.5 X 10~*M. Verapamil produces significant inhibition (F=17.17; p=0.002; df=ll) at 1.5 X 10" 5 M, while the 1,4-dihydropyridine calcium channel antagonists, nicardipine and nifedipine, do not inhibit beyond 1% DMSO controls. Several calmodulin ...
Contributing Partner: UNT Libraries
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