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Opioid/Adrenergic Interaction in Regulating Canine Cardiac Function

Description: Opioid/adrenergic interactions were studied to evaluate two hypotheses: (1) naloxone potentiates the effect of epinephrine on cardiac contractility by increasing circulating epinephrine concentrations; and (2) endogenous and exogenous opioids alter left cardiac nerve stimulationinduced norepinephrine release and cardiac function. A canine isolated heart-lung preparation was used for the first study. Plasma epinephrine was determined and myocardial epinephrine uptake was calculated during intravenous epinephrine infusion. Naloxone (4 mg) was given and the epinephrine infusion was repeated. Naloxone increased cardiac contractility, coronary blood flow, and the coronary sinus epinephrine concentration. When coronary blood flow was subsequently held constant (100% above resting), naloxone increased only contractility. This result indicated that the previously observed increase in coronary sinus epinephrine was flow dependent. Corticosterone (an uptake II blocker) was employed as a positive control. Corticosterone increased the contractile response to epinephrine, but unlike naloxone, corticosterone was accompanied by a clear decrease in myocardial epinephrine uptake. The stereospecificity of the response to naloxone was investigated and (+) naloxone equaled or exceeded (-) naloxone in potentiating the inotropic effect of epinephrine. In the second study, the left cardiac nerve was isolated and electrically stimulated in intact dogs. Norepinephrine overflow gradually declined during successive control stimulations. Pretreatment with naloxone (100 Mg/kg) prevented or delayed the decline. An intracoronary dynorphin 1-9 infusion (2 nmol/min/kg for 20 minutes) reduced both norepinephrine overflow and cardiac performance, and both effects were prevented by pretreatment with naloxone (100 /xg/kg) . To summarize, naloxone potentiated the inotropic effect of infused epinephrine without altering circulating epinephrine concentrations or myocardial epinephrine uptake. This effect of naloxone was not stereospecific and probably not mediated through a traditional opiate receptor. Endogenous and exogenous opioids inhibited the left cardiac nerve stimulation-induced norepinephrine overflow, suggesting that opiate receptors may regulate cardiac excitability by modulating norepinephrine release.
Date: May 1990
Creator: Gu, Hong

Ternary Oxide Structures for High Temperature Lubrication

Description: In this research, a temperature dependent tribological investigation of selected ternary oxides was undertaken. Based on the promising results of previous studies on silver based ternary oxides, copper based ternary oxides were selected to conduct a comparative study since both copper and silver are located in the same group in the periodic table of the elements. Two methods were used to create ternary oxides: (i) solid chemical synthesis to create powders and (ii) sputtering to produce thin films. X-ray diffraction was used to explore the evolution of phases, chemical properties, and structural properties of the coatings before and after tribotesting. Scanning electron microscopy, Auger scanning nanoprobe spectroscopy, and X-ray photoelectron spectroscopy were used to investigate the chemical and morphological properties of these materials after sliding tests. These techniques revealed that chameleon coatings of copper ternary oxides produce a friction coefficient of 0.23 when wear tested at 430 °C. The low friction is due to the formation of copper tantalate phase and copper in the coatings. All sputtering coatings showed similar tribological properties up to 430 °C.
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Date: August 2015
Creator: Gu, Jingjing

Intramolecular [2+2] Cycloadditions of Phenoxyketenes and Intermolecular [2+2] Cycloadditions of Aminoketenes

Description: One objective of this study was to explore the intramolecular [2+2] cycloadditions of phenoxyketenes to carbonyl groups with isoflavones and benzofurans as target compounds. The other objective was to investigate the eyeloaddition reactions of rarely studied aminoketenes. The conversion of 2-(carboxyalkoxy)benzils to the corresponding phenoxyketenes leads to an intramolecular [2+2] cycloaddition to ultimately yield isoflavones and/or 3-aroylbenzofurans. The product distributions are dependent upon the substitution pattern in the original benzil acids. The initial cycloaddition products, β-lactones, are isolated in some instances while some β-lactones spontaneously underwent decarboxylation and could not be isolated. The ketene intermediate was demonstrated in the intramolecular reaction of benzil acids or ketoacids with sodium acetate and acetic anhydride. It is suggested that sodium acetate and acetic anhydride could serve as a source for the generation of ketenes directly from certain organic acids. The treatment of ketoacids with acetic anhydride and sodium acetate provides a simpler procedure to prepare benzofurans than going through the acid chloride with subsequent triethylamine dehydrochlorination to give the ketenes. N-Ary1-N-alkylaminoketenes were prepared for the first time from the corresponding glycine derivatives by using p-toluenesulfonyl chloride and triethylamine. These aminoketenes underwent in situ cycloadditions with cyclopentadiene, cycloheptene and cyclooctenes to yield only the endo -bicyclobutanones. The cycloheptene and cyclooctene cycloaddition products underwent dehydrogenation under the reaction conditions to yield bicycloenamines. A mechanism is proposed for this dehydrogenation involving a radical cation of the arylalkylamine. (N-Phenyl-N-methyl) aminomethylketene was also prepared and found to undergo an intramolecular Friedel-Crafts type acylation to yield an indole derivative when prepared by the acetic anhydride, sodium acetate method. The in situ cycloaddition of N-aryl-N-alkyl aminoketenes with various imines was found to form predominately cis-3-amino-2-azetidinones. A mechanism involving a dipolar intermediate is provided whereby the structure of the intermediate is determined by both electronic and steric effects. The stereochemistry of ...
Date: May 1989
Creator: Gu, Yi Qi

WiFi Networks through Directional Antenna: An Experimental Study

Description: In situations where information infrastructure is destroyed or not available, on-demand information infrastructure is pivotal for the success of rescue missions. In this paper, a drone-carried on demand information infrastructure for long-distance WiFi transmission system is developed. It can be used in the areas including emergency response, public event, and battlefield. The WiFi network can be connected to the Internet to extend WiFi access to areas where WiFi and other Internet infrastructures are not available. In order to establish a local area network to propagate WIFI service, directional antennas and wireless routers are used to create it. Due to unstable working condition on the flying drones, a precise heading turning stage is designed to maintain the two directional antennas facing to each other. Even if external interferences change the heading of the drones, the stages will automatically rotate back to where it should be to offset the bias. Also, to maintain the same flying altitude, a ground controller is designed to measure the height of the drones so that the directional antennas can communicate to each other successfully. To verify the design of the whole system, quite a few field experiments were performed. Experiments results indicates the design is reliable, viable and successful. Especially at disaster areas, it’ll help people a lot.
Date: May 2015
Creator: Gu, Yixin

Women and the Superintendency: a Study of Texas Women Superintendents

Description: Education remains one of the most gender imbalanced fields, with disproportionately fewer women in higher levels of leadership. Women who reach leadership positions in education experience many triumphs and tribulations during their tenures as principals, assistant superintendents, and superintendents. The experiences of these women in their various administrative levels of leadership can provide important insight into the reasons for their success as women superintendents in Texas. This research has probed the career trajectory of nine women who have successfully attained and retained superintendencies in Texas to determine what career decisions have helped them and the challenges these women have faced in their positions. A qualitative research method, open-ended interviews, yielded several findings of what women considered important in proceeding from teaching through the various levels and ending in becoming superintendents. According to nine successful women superintendents in Texas, there are specific characteristics one can bring to the table that would really make a difference: Communication, collaboration, compassion, preparedness, hard work, and passion. All nine participants overcame challenges when climbing to the higher levels of leadership in education. These women have achieved success in the superintendency, and several factors appear to have played into the success of these women who have achieved in education’s top position.
Date: August 2015
Creator: Guajardo, Lesli Ann

Autonomic Failure Identification and Diagnosis for Building Dependable Cloud Computing Systems

Description: The increasingly popular cloud-computing paradigm provides on-demand access to computing and storage with the appearance of unlimited resources. Users are given access to a variety of data and software utilities to manage their work. Users rent virtual resources and pay for only what they use. In spite of the many benefits that cloud computing promises, the lack of dependability in shared virtualized infrastructures is a major obstacle for its wider adoption, especially for mission-critical applications. Virtualization and multi-tenancy increase system complexity and dynamicity. They introduce new sources of failure degrading the dependability of cloud computing systems. To assure cloud dependability, in my dissertation research, I develop autonomic failure identification and diagnosis techniques that are crucial for understanding emergent, cloud-wide phenomena and self-managing resource burdens for cloud availability and productivity enhancement. We study the runtime cloud performance data collected from a cloud test-bed and by using traces from production cloud systems. We define cloud signatures including those metrics that are most relevant to failure instances. We exploit profiled cloud performance data in both time and frequency domain to identify anomalous cloud behaviors and leverage cloud metric subspace analysis to automate the diagnosis of observed failures. We implement a prototype of the anomaly identification system and conduct the experiments in an on-campus cloud computing test-bed and by using the Google datacenter traces. Our experimental results show that our proposed anomaly detection mechanism can achieve 93% detection sensitivity while keeping the false positive rate as low as 6.1% and outperform other tested anomaly detection schemes. In addition, the anomaly detector adapts itself by recursively learning from these newly verified detection results to refine future detection.
Date: May 2014
Creator: Guan, Qiang

The Function of Social Structure in Controlling Violent Crime in Turkey

Description: This dissertation examines the relationship between social structural factors and violent crime rates in Turkey. The relationship between social structural characteristics and violent crime is worth exploring in areas that have attracted little academic attention, such as violent crime in Turkey. In order to understand and prevent the occurrence of crime, researchers have long investigated possible factors related to crime. Examining how crime varies across different regions can help us to understand underlying reasons for violent crime, which is considered one of the enduring problems in society. The findings of this research, to some extent, support the assumptions of social disorganization theory regarding the distribution of violent crime. Both the findings of multivariate and bivariate analysis indicated that poverty, unemployment, and family disruptions may have a positive effect on the distribution of violent crime in the cities of Turkey. The analysis of the effects of the social structure variables through the mediating variables, such as religious institutions, libraries and voluntary associations on the number of violent crimes and violent criminals, to some extent, support the tenets of social disorganization theory. However, all mediating variables cannot mediate all the indirect effects of social structural covariates. In brief, none of their indirect impacts on the social structural variables on the outcome variable was significant via mediating variables.
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Date: December 2010
Creator: Guclu, Idris

The Information-Seeking Behavior of Police Officers in Turkish National Police

Description: A current trend that has emerged as a result of the information age is information-seeking behavior. From individuals to large social institutions, information-seeking behavior is utilized to attain a wide variety of goals. This body of work investigates the information-seeking behaviors of police officers who work in police stations in the Turkish National Police force. The study utilizes Leckie et al.’s (1996) model of information-seeking behavior of professionals. The findings indicated that police officers initially consulted their personal knowledge and experience. Next, officers rely upon their colleagues and then official documents. These information sources were consulted in the context of both conducting tasks and staying current. However, contrary to expectation, they rarely consulted informants. In addition police officers rarely consulted printed journals, libraries, books and attendance at conferences as information sources. The results of this study show that there were significant differences in the information sources used by police officers based on their gender in the context of staying current. On the other hand, there were no significant differences in the context of conducting police station tasks, by gender. Surprisingly, there were no significant differences in the information sources used by police officers based on their educational level. There were significant differences in the use of information sources by age, service years in police stations and service years in policing in the context of conducting police station tasks. Lastly, the results of this study indicated that service years in policing and the roles in police station were significantly correlated with the information sources used by police officers regarding staying current. This body of work offers insight into the factors that guide the information-seeking behaviors of police officers.
Date: August 2011
Creator: Guclu, Idris

Identifiable Factors Which May Cause Delinquency Among Children of Elementary Age in Gainesville, Texas

Description: It is the purpose of this study to determine the identifiable causes of delinquency among children of elementary age in Gainesville and to make proposals for more effective youth services. To do this an analysis will be made of the possible sources and causes of delinquency, a modern educational approach, and the relation between the two.
Date: 1949
Creator: Gudgell, Arie Allen

A Measurement System for Monitoring Play in Typically Developing Children and Children with Autism

Description: A comprehensive measurement system was developed to monitor play in children with autism and typically developing children. The study was conducted in a preschool operated in conjunction with a center-based program for children with autism. The development of the measurement system was based on observations of four children with autism and three typically developing children during social and play activites. Data were collected on material use and several dimensions of play: Simple Manipulation, Functional Manipulation, Symbolic Toy Play, Symbolic Role Play and Play Themes. The results indicated that the measurement system consistently measured a wide range of play behaviors across children and materials. Significance of the information gathered from the measurement system in assessing play and designing interventions is discussed.
Date: May 2002
Creator: Gudmundsdottir, Kristin

Life History Biology of the Desert Nesting Seagull Larus modestus

Description: Gray gulls Larus modestus are unique among birds of northern Chile as the only species nesting in the interior Atacama Desert, and the only seagull nesting far (30 - 100 km) from surface water. During breeding-nesting (August - February) gray gulls congregate on the coast of northern Chile where they feed and initiate courtship. As early as August, breeding pairs commute daily to the inner desert to establish nesting territories, round-trip distances of 60-200 Km. During incubation (30 days) and brooding (7 days) adults alternate daily foraging flights to the coast. Afterwards, both adults forage daily for their chick(s) until fledging (ca. 60 days). Foraging flights and thermoregulatory costs during the period of maximal solar radiation, when ground temperatures may reach 61 C in the day and drop to 2 C at night, have selected for adaptations which minimize those costs: tolerance of hypothermia and hyperthermia; dark plumage; low egg-shell water vapor conductance; low standard metabolic rate; elaborate repertory of thermoregulatory behavior which allow adults to take advantage of microclimatic variations in the desert and minimize costs relative to a sympatric congenor, Larus belcheri scheduling foraging flights to take advantage of optimal atmospheric conditions and presence of forage fish (anchovies) close to the surface; scheduling migration to coincide with anchovy production and levels of interspecific competition; and reduced clutch size ( ≤ 2) relative to most seagulls. Periodic El Nino-Southern Oscillations (ENSO), which reduce principal food items of gray gulls, have selected for 'bet hedging" tactic by which L. modestus either ceases reproduction or varies clutch size between one and two, as observed during and after the 1982-83 ENSO. During a typical reproductive season, breeding pairs allocate a minimum of 39 percent of their net metabolized energy (NME) to foraging flights. Including energy content of eggs, females have an overall ...
Date: December 1987
Creator: Guerra Correa, Carlos Guillermo

The Effects of Neighboring, Social Networks, and Collective Efficacy on Crime Victimization: an Alternative to the Systemic Model

Description: The systemic model posits that informal social control directly reduces crime victimization and social networks indirectly reduce crime victimization through informal social control. While empirical testing of the systemic model advanced the theory, important analytical issues remain. First, social networks are inconsistently conceptualized and measured. Second, the conceptual relationship between social networks and informal social control remains unclear. This study addresses these issues by testing an alternative to the systemic model, including new constructs and hypotheses. The goal is to develop better indicators for the model and refine the theory, rethinking and deepening the existing theory about neighborhood effects on crime victimization. The data come from the 2002-2003 Seattle Neighborhoods and Crime Survey (N=2,200). Structural equation modeling (SEM), a multivariate statistical technique, was used to analyze these data. The SEM included five latent constructs (neighboring, neighborhood and non-neighborhood social networks, collective efficacy, and crime victimization) and six social structural variables (racially homogeneous neighborhood, resident tenure, household income, family disruption, male, and non-white ethnicity). One of my 9 hypotheses was supported; the remaining hypotheses were partly supported. The results support my argument that the systemic model is too simplistic, but the relationships among the variables are not exactly as I hypothesized. The results provide insight into the complexities of the systemic model and areas for future research.
Date: May 2015
Creator: Guerrero-Soto, Anthony Jaime

The Characterstücke of Johannes Brahms

Description: With the advent of the Ballades, Intermezzi, Cappriccios and Rhapsodies of Johannes Brahms the musical world was to witness the apex of a development of a particular style of pianoforte composition which began in the nineteenth century with the publication in 1803 of a group of seven pieces called Bagatelles, opus 33 by Ludwig van Beethoven. This style thus originated was the Caracterstücke.
Date: August 1955
Creator: Guerry, Jack, 1931-

A Decay Scheme for 164 Ho

Description: The present investigation was prompted by several considerations. In previous studies there was considerable variance with regard to the reported values for the half-lives of the isomeric and ground states in 164 Ho. There was also considerable variance with regard to the values reported for the branching ratios and the relative intensities of the transitions. Thus a further study of the problem was needed.
Date: December 1972
Creator: Guertin, James

Letter to the Editor

Description: Letter written to the editor of the Journal of Near-Death Studies on the topic "Could Endorphins Participate in the Limbic Pathways Responsible for NDEs after Acute Cerebral Hypoxia?"
Date: Spring 1997
Creator: Guevara, Patricia
Item Type: Letter

Iconic Ida: Tennyson's The Princess and Her Uses

Description: Alfred Lord Tennyson's The Princess: A Medley has posed interpretative difficulties for readers since its 1847 debut. Critics, editors, and artists contemporary with Tennyson as well as in this century have puzzled over the poem's stance on the issue of the so-called Woman Question. Treating Tennyson as the first reader of the poem yields an understanding of the title character, Princess Ida, as an ambassador of Tennyson's optimistic and evolutionary views of human development and links his work to that of visionary educators of nineteenth-century England. Later artists, however, produced adaptations of the poem that twisted its hopefulness into satirical commentary, reduced its complexities to ease the task of reading, and put it to work in various causes, many ranged against the improvement of women's condition. In particular, a series of editions carried The Princess into various nations, classrooms, and homes, promoting interpretations that often obscure Tennyson's cautious optimism.
Date: May 1997
Creator: Guidici, Cynthia (Cynthia Dianne)

The Apostasy (and Return) of Lenny Gorsuch

Description: This comic romantic novel engages the question of how the Christianity of the southern, fundamentalist world of the Texas bible belt, finding its primary cultural assumptions about human existence challenged by the more confusing elements of a modern sensibility, a sensibility over-laden with strange-attractors, mechanistic psychologies, relativistic physics and ethics, evolutionary premises, newly proclaimed rights and freedoms, a deterioration in cultural political naivete, and the advent of an increasingly incomprehensible set of technologies, can survive. The "central" character is a young, slightly deformed man raised by his ostensibly "Christian" grandparents who, through a rather odd set of legal circumstances and physical events, not only become wealthy, but somewhat powerful in their immediate community. He finds himself involved with a young woman, raised in an equally "Christian" household, but, as is true of any romantic plot, the relationship between the two is destined, by virtue of circumstance and the meddling of other characters, to struggle and mishap. In the end, the text, in its own fashion, asserts that the Christian impulse can survive the modern era by virtue of one of its central tenets: faith, in the Christian world, is very much the same as life itself, a process of waiting and expecting. Its greatest threat, rather than something intrinsic to the modern period, is perhaps that of the dogmatism and misunderstanding of the characters who most loudly proclaim it to others.
Date: August 1998
Creator: Guidici, Guy R.

Subcloning and Nucleotide Sequence of the xylO/PUWCMA Region from the Pseudomonas putida TOL Plasmid pDK1

Description: The TOL plasmids of Pseudomonas putida encode enzymes required for the oxidation of toluene and other related aromatic compounds. These genes are organized into two operons, the xylUWCMABN operon (upper), and the xylXYZLTEGFJQKIH operon (lower). Here we report the nucleotide sequence of a 7107 bp segment of the TOL pDK1 plasmid encoding the region just upstream of the "upper" operon through the genes encoding xylUWCMA. Sequence analysis, comparison of base-usage patterns, codon-usage patterns, and intergenic distances between genes help support the idea that the "upper" and "lower" operons have evolved independently in different genetic backgrounds and have only more recently been brought together in TOL and related catabolic plasmids.
Date: December 1997
Creator: Guigneaux, Michelle M. (Michelle Marie)

A Decade of Grammatical Liberalism

Description: Against the background of conservatism, liberalism, and counter-reaction among linguists, this study will survey the degrees of liberality shown by the writers of a group of present-day handbooks and grammars toward six disputable issues.
Date: January 1955
Creator: Guinn, James M.

Parent-adolescent Attachment, Bullying and Victimization, and Mental Health Outcomes

Description: Traditional and cyber bullying have been identified as universal problematic issues facing adolescents, and research is needed to understand correlates associated with these phenomena. Structural equation modeling analyses examined associations between attachment to parents, traditional and cyber bullying or victimization, and mental health outcomes among 257 high school students (Average age 15.9 years). Key patterns emerged, including associations between maternal attachment and mental health outcomes; victimization and mental health concerns; and bullying and victimization in both traditional and cyber contexts. The role of attachment to mothers and fathers varied by context. Findings extend the literature by identifying risk factors in adolescence associated with bullying and victimization, as well as suggesting appropriate prevention and intervention strategies to increase adolescent well-being.
Date: December 2015
Creator: Guinn, Megan D.

Sibling Relationship Quality: Associations with Marital and Coparenting Subsystems

Description: Marital relationships play an important role in family functioning and in the development of sibling relationships. From a family systems perspective, other subsystems within the family, such as coparenting interactions, could explain the effects of the marital relationship on sibling bonds. Specifically, the quality of the coparenting relationship may mediate the association between marital functioning and sibling relationship quality. The current study examined relationships between these three subsystems (marital, coparenting, and sibling) as self-reported by mothers, fathers, and children with siblings. As part of a larger project, families with a child aged 8 to 11 and at least one sibling (N = 75) completed the Dyadic Adjustment Scale and the Coparenting Scale (both completed by mother and father), as well as the Sibling Relationship Questionnaire (completed by target child). Results suggested that marital functioning is a significant predictor of functioning within the coparenting relationship. Predicted associations did not emerge between sibling relationship quality and marital or coparenting relationships, with minor exceptions, and the coparenting relationship did not mediate the association between marital and sibling relationship quality. Implications of the current findings and suggestions for future research are discussed.
Date: December 2012
Creator: Guinn, Megan D.