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Showing papers by "University of North Carolina at Charlotte published in 1993"


Book ChapterDOI
01 Jan 1993
TL;DR: It is realized that some bacteria, in response to certain environmental stresses, may lose the ability to grow on media on which they are routinely cultured, while remaining viable, and is of special concern when considering release into the environment of genetically engineered microorganisms and human pathogens.
Abstract: It has long been realized that plate counts can dramatically underestimate the total number of bacteria (typically determined by direct microscopic examination) present in samples taken from natural environments. In the late 1970s, several easily performed noncultural methods (Zimmerman et al., 1978; Kogure et al., 1979) for determining cell viability allowed confirmation of earlier microautoradiographic studies (e.g., Hoppe, 1976) which demonstrated that many of these nonculturable cells are indeed viable and able to actively metabolize. Such studies led to the further realization that some bacteria, in response to certain environmental stresses, may lose the ability to grow on media on which they are routinely cultured, while remaining viable. This state is of considerable interest to our understanding of microbial ecology. It is of special concern when considering release into the environment of genetically engineered microorganisms, and for those indicator bacteria (e.g., coliforms) and human pathogens which enter this nonculturable state and are thus not detectable through routine bacteriological procedures.

355 citations


Journal ArticleDOI
TL;DR: In this article, the authors examined the role of theoretical variables associated with both female and male gang membership and concluded that involvement in gangs is associated with substantially increased levels of delinquency and substance use.
Abstract: The purpose of this paper is to respond to gaps in our knowledge about patterns of female gang participation and its causes and consequences. Data from the Rochester Youth Development Study, a panel study that overrepresents adolescents at high risk for delinquency, are used to compare gang participation and delinquent involvement of female and male adolescents. We then examine the role of theoretical variables associated with both female and male gang membership. The results lead us to conclude that, for females as well as males, involvement in gangs is associated with substantially increased levels of delinquency and substance use. There is also some similarity in the factors associated with gang membership for both sexes, although lack of school success emerges as a factor of particular salience for female adolescents. The results suggest that theory and intervention need to address the phenomenon of female gang membership as an important component of urban youth problems.

248 citations


Journal ArticleDOI
TL;DR: This article investigated the channels through which partisan influence from a Presidential administration could affect monetary policy-making and found that the appointments process is the primary mechanism by which partisan differences in monetary policies arise.
Abstract: We investigate the channels through which partisan influence from a Presidential administration could affect monetary policy-making. Influence could be a result of direct Presidential pressure exerted on members of the Federal Open Market Committee (FOMC), or it could be a result of partisan considerations in Presidential appointments to the Board of Governors. To investigate these two channels of influence, we devise and apply a method for estimating parameters of monetary policy reaction functions that can vary across individual members of the FOMC. Our results suggest that the appointments process is the primary mechanism by which partisan differences in monetary policies arise.

192 citations


Journal ArticleDOI
TL;DR: The authors propose that, by nature, inquiry, discovery, and theoretical interpretation coexist simultaneously and must be recognized as such if the theory-research linkage is to advance nursing science through qualitative research.
Abstract: Increasingly philosophers and scientists have affirmed that all knowledge is theory-laden and that methods are theory-driven. These assertions raise important questions related to the role of theory in qualitative research. There are scholars who propose that qualitative research can enhance understanding and expand theoretical knowledge from a disciplinary perspective. And there are others who contend that qualitative inquiry is purely inductive and that its validity can therefore be judged by the extent to which preconceived theory is absent from it. The purpose of this article is to examine three qualitative methods, grounded theory, ethnography, and phenomenology, and their use in nursing in order to explicate the role of theory in knowledge development. The authors propose that, by nature, inquiry, discovery, and theoretical interpretation coexist simultaneously and must be recognized as such if the theory-research linkage is to advance nursing science through qualitative research.

125 citations


Journal ArticleDOI
TL;DR: In this paper, the cumulative distribution plot on a normal probability graph is used to characterize the texture of a plateau-enhanced cylinder liners for internal combustion engines, and an alternate approach is proposed based on analyzing the cumulative distributions of the normal probability graphs.
Abstract: The plateau honing operation is being widely used for finishing of cylinder liners for internal combustion engines Plateau honing has been shown to significantly reduce the costly running-in period due to the fact that very little further modification of the texture is required once the liner is put into operation In order to better understand, control, and ultimately “engineer” plateau honed surfaces, a comprehensive means of characterizing this texture is required In this paper the techniques currently used are briefly reviewed and an alternate approach is proposed The proposed approach is based on analyzing the cumulative distribution plot on a normal probability graph

118 citations


Proceedings ArticleDOI
02 Oct 1993
TL;DR: In this article, the geometry of Halbach arrays in Cartesian, polar, and cylindrical coordinates is presented for magnetic excitation in synchronous machines and a Cartesian linear motor is optimized for use in conjunction with high-precision magnetic suspension stages for photolithography.
Abstract: The authors demonstrate that the Halbach array is highly applicable for magnetic excitation in synchronous machines. To this end, they present the geometry of Halbach arrays in Cartesian, polar, and cylindrical coordinates. They also present the design of a Cartesian linear motor which has been optimized for use in conjunction with a class of high-precision magnetic suspension stages for photolithography. They give analytical solutions for this motor's fields, forces, commutation structure, and power dissipation. Results for the power-optimum thickness of the stator windings are obtained. It is suggested that an equivalent Halbach geometry electromagnet may find utility in areas such as magnetically levitated trains. >

109 citations


Book ChapterDOI
01 Feb 1993-Genetica
TL;DR: Principal components analysis and canonical correlation analysis confirmed the overall higher level of integration of FAs among the subpopulations and within the two character groupings.
Abstract: Morphological integration of fluctuating asymmetry (FA) was assessed for nine mandibular characters in random-bred house mice to test the hypothesis that there should be a significant integration or concordance of FAs at the population level, but not at the individual level. FA estimates for each of the nine characters were made for each of 16 subpopulations (two replicates each for mice varying in sex and age) and their correlations indicated a moderate level of integration (index of integration = 0.42). A matrix permutation test of the differences of the correlations within two (‘incisor’ and ‘muscle’) developmentally different character groups versus correlations between groups was significant, indicating the presence of morphological integration.Kendall’s coefficient of concordance also indicated a significant population asymmetry parameter for FAs within the two character groups. Correlations among individual FA estimates were generally lower than those calculated from subpopulations, the index of integration being 0.21. The matrix permutation test failed to show significant morphological integration among individual FAs, but Kendall’s coefficient of concordance was significant, indicating the presence of an ’individual asymmetry parameter’ among the nine characters. Principal components analysis and canonical correlation analysis confirmed the overall higher level of integration of FAs among the subpopulations and within the two character groupings.

108 citations


Journal ArticleDOI
TL;DR: This paper found that failure to include more elusive respondents (those who are more mobile) would bias estimates of prevalence and frequency of delinquency and drug use as well as results from basic regression analyses.
Abstract: Subject attrition is a potentially serious threat to the validity of inferences drawn from panel studies of delinquency and drug use. Prior assessments of this issue produce somewhat conflicting results, with some finding that respondents who leave the panel have higher rates of delinquency and drug use than those who remain, while other studies report little or no differential attrition. Despite these findings, there has been virtually no examination of the extent to which respondent attrition can bias substantive findings in panel studies of delinquency and drug use. The present article addresses this issue by simulating higher levels of attrition in an ongoing panel study that has a low rate of attrition and little differential attrition. It finds that failure to include more elusive respondents (those who are more mobile) would bias estimates of prevalence and frequency of delinquency and drug use as well as results from basic regression analyses. Failure to include less cooperative respondents (those who require more contacts) produces similar, but somewhat smaller, differences. The methodological implications of the results are discussed.

94 citations


Journal ArticleDOI
TL;DR: In this paper, a model of average scholastic aptitude test (SAT) scores that are a function of pigskin success, hoop success and key academic variables for the universities that engage in major intercollegiate athletics is presented.

88 citations


Journal ArticleDOI
TL;DR: In this article, the authors examined the effect of leader-member exchange on the relationship between employee performance and the supervisor's rating of that performance and found that poorly performing high LMX employees were given high performance ratings, regardless of their actual performance.
Abstract: This study examined the effect of leader-member exchange (LMX) on the relationship between employee performance (measured objectively) and the supervisor's rating of that performance. To date, no field study has tested whether high and low LMX members receive differential ratings based on their LMX relationship, beyond their actual performance. Data were collected from employees (directory assistants, cable technicians, and dispatch clerks) and their supervisors in a telephone company. The objective measures of performance which were available for these jobs were related to supervisory ratings of performance for high and low LMX employees. The results showed that poorly performing high LMX employees were given high performance ratings, regardless of their actual performance. The ratings of low LMX employees were consistent with their actual performance. The effect of LMX was more pronounced with more general task and relationship rating categories. Alternative explanations of the results, as well as the theoretical and practical implications for performance appraisal and LMX research, were discussed.

86 citations


Journal ArticleDOI
TL;DR: In this article, the authors investigated the relationship between teacher job satisfaction and the leadership behaviors of "telling,” "selling", and "salesperson" using Hersey and Blanchard's concept of situational leadership.
Abstract: This study made use of Hersey and Blanchard's concept of situational leadership to investigate the relationship between teacher job satisfaction and the leadership behaviors of “telling,” “selling,...

Journal ArticleDOI
TL;DR: A scoring system is described for the precise and quantified comparison of frontal sinuses in antemortem to postmortem CT scans and the application of these procedures to actual cases is described.

Journal ArticleDOI
TL;DR: The method of auxiliary mapping (MAM) as discussed by the authors has been shown to achieve exponential convergence for homogeneous Laplace equations with boundary singularities and Helmholtz equations with singularities.

Proceedings ArticleDOI
07 Feb 1993
TL;DR: Integrated force arrays (IFAs) as mentioned in this paper are flexible metallized membranes that can be patterned using the techniques of VLSI electronics and undergo substantial deformation when voltage is applied.
Abstract: Integrated force arrays (IFAs), which are flexible metallized membranes that can be patterned using the techniques of VLSI electronics and that undergo substantial deformation when voltage is applied, have been developed. They may be configured as macroscopic actuators or used in highly articulated systems of great complexity. The theory of operation, the methods of construction, and the observational results for IFA test structures are presented. >

Journal ArticleDOI
TL;DR: In this article, the authors examined cervical swabs of 375 women for HPV DNA using polymerase chain reaction (PCR) and ViraPap with an expanded probe range and found no statistically significant association between the prevalence at any level of infection and pregnancy status.

Journal ArticleDOI
TL;DR: The relative abundance of 88 proteins was measured in extracts from three strains of Escherichia coli K‐12 that are isogenic except for the topA and gyrB genes, suggesting that small, non‐lethal changes in DNA supercoiling can have widespread effects on patterns of gene expression.
Abstract: Summary The relative abundance of 88 proteins was measured in extracts from three strains of Escherichia coli K-12 that are isogenic except for the topA and gyrB genes. Mutations in these genes slightly raise or lower, respectively, steady-state DNA supercoiling levels but have little effect on growth rate. Altered protein abundances were observed in the mutant strains relative to wild type. Many proteins exhibited minimum abundance at wild-type supercoiling levels, and other proteins exhibited maximal abundance at relaxed levels. A smaller number showed maximal abundance at elevated levels of supercoiling. These data suggest that small, non-lethal changes in DNA supercoiling can have widespread effects on patterns of gene expression.

Proceedings ArticleDOI
02 May 1993
TL;DR: A method for obtaining sufficient topological contact information from the current position/orientation data for the objects and geometric models involved, taking into account sensing uncertainties, is introduced to achieve automatic recognition of unknown contact situations in spite of uncertainties.
Abstract: A method for obtaining sufficient topological contact information from the current position/orientation data for the objects and geometric models involved, taking into account sensing uncertainties, is introduced. The information obtained can serve as a basis for further and more accurate extraction of the topological contact data using additional sensing means, such as vision and force/moment sensing. The aim is to achieve automatic recognition of unknown contact situations in spite of uncertainties. The method is discussed in detail for contacts between 2-D polygons and can be extended to 3-D polyhedra. The key idea is to discretize the continuous region of uncertain configurations of an object so that the topological contacts formed at those finite and discrete configurations constitute all possible contact situations taking into account uncertainties. To accomplish this, some general geometric constraints on the objects, which are easy to satisfy, are imposed. >


Journal ArticleDOI
TL;DR: In this article, it was shown that the problem of uniform motion of a submerged body is solvable for all velocities except, possibly, for a finite number, where the advantage of these representations is that they are uniform with respect to all directions and depth.

Journal ArticleDOI
TL;DR: It is argued that (for a particular problem) stronger evolution programs (in terms of the problem-specific knowledge incorporated in the system) should perform better than weaker ones.
Abstract: In this paper we present the concept of evolution programs and discuss a hierarchy of such programs for a particular problem. We argue that (for a particular problem) stronger evolution programs (in terms of the problem-specific knowledge incorporated in the system) should perform better than weaker ones. This hypothesis is based on a number of experiments and a simple intuition that problem-specific knowledge enhances an algorithm's performance; at the same time it narrows the applicability of an algorithm. Trade-offs between the effort of finding an effective representation for general-purpose evolution programs and the effort of developing more specialized systems are also discussed.

Journal ArticleDOI
TL;DR: In this paper, the effects of repeated readings, intonation training and segmentation training on reading rate and reading comprehension were investigated with thirty fourth and fifth graders, reading below grade level.
Abstract: Thirty fourth and fifth graders, reading below grade level, participated in a study to investigate the effects of repeated readings, intonation training and segmentation training on reading rate and reading comprehension. The dependent variables were reading rate and comprehension. These measures were collected for passages read under each level of the repeated reading variable. A 2 x 3 mixed design with one between and one within group factor was used and two separate ANOVA's, one for each dependent variable were calculated. A significant increase in reading rate was noted as the number of repeated readings increased from one to three to seven. Comprehension also significantly increased when the students read the passage three times instead of one time and seven times instead of one time. Students trained to segment sentences did read at a faster rate and scored higher in comprehension than those students given intonation training, but not to a statistically significant degree. No interaction wa...

Journal ArticleDOI
TL;DR: College students’ perceptions of the sex typing of 129 occupations were gathered and compared with those reported by Shinar (1975), indicating that occupational sex typing continues to exist and that women tend to perceive jobs as being more neutral than men do.
Abstract: College students’ perceptions of the sex typing of 129 occupations were gathered and compared with those reported by Shinar (1975). Questionnaires were completed by 72 males and 70 females. As in Shinar's study, a continuum of the perceptions of occupations from masculine to feminine was replicated. A comparison of the mean ratings for the occupations and of the percentages of women in each occupation in 1975 and 1988 is reported in a comprehensive table. The results indicated that occupational sex typing continues to exist and that women tend to perceive jobs as being more neutral than men do. However, the occupational sex typing may not be based on the actual percentages of women in the occupations.

Journal ArticleDOI
TL;DR: The hydrology and elemental transport within five low-order Precambrian shield catchments was investigated during 1988-90 as discussed by the authors, and the dominant hydrologic pathways were Horton overland flow in the lichen-bedrock areas and shallow subsurface flow through organic rich LFH (forest floor) and Ah soil horizons in the forested areas.
Abstract: The hydrology and elemental transport within five low order Precambrian shield catchments was investigated during 1988–90. Catchments were subdivided and instrumented to examine the vertical and horizontal fluxes of elements within and between two distinct landscape types: open, lichen-covered bedrock outcrops and patches of conifer forest. The dominant hydrologic pathways were Horton overland flow in the lichen-bedrock areas and shallow subsurface flow through organic rich LFH (forest floor) and Ah soil horizons in the forested areas. Annual runoff coefficients ranged from 0.3 to 0.7.

Journal ArticleDOI
TL;DR: This study addressed the stability of informed death penalty opinions (and reasons for opinions) by examining them approximately two and three years after subjects completed a month-long college class on the death penalty.

Journal ArticleDOI
TL;DR: In this paper, it was shown that if B is t-linked over A, then the map I →( IB ) t gives a homomorphism from the group of t-invertible t-ideals of B to the group T-ideal of A. Conditions are given for these maps to be surjective which extend Nagata's Theorem for Krull domains to a much larger class of domains including Noetherian domains.

Journal ArticleDOI
TL;DR: In this article, the authors examine outpatient commitment from two points of view: clinicians (the controllers) and clients (the controlled) and conclude that clinicians favored the greater control over clients' outpatient commitment provided and clients were cognisant of the greater liberty it afforded them.
Abstract: This paper utilises qualitative data to examine outpatient commitment from two points of view: clinicians (the controllers) and clients (the controlled). Outpatient commitment is a legal mechanism whereby ‘mentally ill’ individuals are court-ordered to report to their community mental health centre for treatment. In this paper I provide the reader with an understanding of how outpatient commitment works by allowing clinicians and clients to describe the meaning outpatient commitment has for them. While the experience of outpatient commitment varies, and supports the contention that there are multiple definitions of reality, it is clear that in general clinicians favoured the greater control over clients’ outpatient commitment provided and clients were cognisant of the greater liberty it afforded them. This has important theoretical implications for research into medicalisation and social control, in that providers and clients interpret medical dominance and ideology differentially. Consequently I analyse the interpretations of controllers and controlled from those sociological perspectives relevant to the issues of ideology, power, and social control. I conclude by calling for further investigation of those agents who seek to engage in ‘heretical discourse’ (Bourdieu 1991) which challenge dominant medical constructions.

Journal ArticleDOI
TL;DR: La presente etude epidemiologique en dresse un tableau lie au contexte social du pays de 1870 a 1940.
Abstract: Jusqu'en 1940, le typhus a fait un ravage dans la population russe. La presente etude epidemiologique en dresse un tableau lie au contexte social du pays de 1870 a 1940

Journal ArticleDOI
TL;DR: In this paper, a finite element-based simulation of the plasma arc welding process is presented, which determines the weld pool's three-dimensional capillary surface shape, the approximate solid-liquid phase boundary, and calculates the pool's 3D flow and temperature fields.

Journal Article
TL;DR: A qualitative study of child-rearing stressors of 13 parents: 10 patients with cancer and 3 of their spouses, and parents' perceptions of child stressors and coping strategies.
Abstract: A diagnosis of cancer creates multiple problems for families, including major changes in life-styles, relationships, communication, roles, and living patterns. This article describes the results of a qualitative study of child-rearing stressors of 13 parents: 10 patients with cancer and 3 of their spouses. Data were collected using open-ended interviews. The major categories derived from the data were parent stressors and coping strategies, and parents' perceptions of child stressors and coping strategies. Parent stressors were related to the parents' knowledge and feelings, to their children, and to parent-child communication. Parent coping strategies included seeking support, making decisions, talking with the children, making alternative childcare arrangements, and trying to be supportive to child and spouse. Child stressors identified by the parents included changes in family life-style, embarrassment over the parent's appearance, hospital visiting, and obtaining information. Nursing interventions based on the identified stressors are suggested.

Journal ArticleDOI
TL;DR: In this article, the weak scattering case of a 3D inverse scattering problem is studied in the framework of a Quasi-Newton method, which is defined in the iterative sequence.