Showing papers by "University of South Carolina published in 2000"

Compendium of physical activities: an update of activity codes and MET intensities.

Abstract: We provide an updated version of the Compendium of Physical Activities, a coding scheme that classifies specific physical activity (PA) by rate of energy expenditure. It was developed to enhance the comparability of results across studies using self-reports of PA. The Compendium coding scheme links a five-digit code that describes physical activities by major headings (e.g., occupation, transportation, etc.) and specific activities within each major heading with its intensity, defined as the ratio of work metabolic rate to a standard resting metabolic rate (MET). Energy expenditure in MET-minutes, MET-hours, kcal, or kcal per kilogram body weight can be estimated for specific activities by type or MET intensity. Additions to the Compendium were obtained from studies describing daily PA patterns of adults and studies measuring the energy cost of specific physical activities in field settings. The updated version includes two new major headings of volunteer and religious activities, extends the number of specific activities from 477 to 605, and provides updated MET intensity levels for selected activities.

Why Companies Go Green: A Model of Ecological Responsiveness

Abstract: The authors conducted a qualitative study of the motivations and contextual factors that induce corporate ecological responsiveness. Analytic induction applied to data collected from 53 firms in the United Kingdom and Japan revealed three motivations: competitiveness, legitimation, and ecological responsibility. These motivations were influenced by three contextual conditions: field cohesion, issue salience, and individual concern. In this article, the authors also identify the conditions that likely lead to high corporate ecological responsiveness.

Effects of Age at Entry, Knowledge Intensity, and Imitability on International Growth

Abstract: We employed knowledge-based theory to shed light on international growth in entrepreneurial firms. We found earlier initiation of internationalization and greater knowledge intensity to be associat...

Experiencing Transitions: An Emerging Middle-Range Theory

Abstract: Changes in health and illness of individuals create a process of transition, and clients in transition tend to be more vulnerable to risks that may in turn affect their health. Uncovering these risks may be enhanced by understanding the transition process. As a central concept of nursing, transition has been analyzed, its components identified, and a framework to articulate and to reflect the relationship between these components has been defined. In this article, the previous conceptual analysis of transitions is extended and refined by drawing on the results of five different research studies that have examined transitions using an integrative approach to theory development. The emerging middle-range theory of transitions consists of types and patterns of transitions, properties of transition experiences, facilitating and inhibiting conditions, process indicators, outcome indicators, and nursing therapeutics. The diversity, complexity, and multiple dimensionality of transition experiences need to be further explored and incorporated in future research and nursing practice related to transitions.

Revealing the Vulnerability of People and Places: A Case Study of Georgetown County, South Carolina

Abstract: Losses from environmental hazards have escalated in the past decade, prompting a reorientation of emergency management systems away from simple postevent response. There is a noticeable change in p...

Physical Health Consequences of Physical and Psychological Intimate Partner Violence

Abstract: Background: Past studies that have addressed the health effects of intimate partner violence (IPV) have defined IPV as violence based on physical blows that frequently cause injuries. To our knowledge, no epidemiologic research has assessed the physical health consequences of psychological forms of IPV. Objective: To estimate IPV prevalence by type and associated physical health consequences among women seeking primary health care. Design: Cross-sectional survey. Setting and Participants: A total of 1152 women, aged 18 to 65 years, recruited from family practice clinics from February 1997 through January 1999 and screened for IPV during a brief in-clinic interview; health history and current status were assessed in a follow-up interview. Results: Of 1152 women surveyed, 53.6% ever experienced any type of partner violence; 13.6% experienced psychological IPV without physical IPV. Women experiencing psychological IPV were significantly more likely to report poor physical and mental health (adjusted relative risk [RR], 1.69 for physical health and 1.74 for mental health). Psychological IPV was associated with a number of adverse health outcomes, including a disability preventing work (adjusted RR, 1.49), arthritis (adjusted RR, 1.67), chronic pain (adjusted RR, 1.91), migraine (adjusted RR, 1.54) and other frequent headaches (adjusted RR, 1.41), stammering (adjusted RR, 2.31), sexually transmitted infections (adjusted RR, 1.82), chronic pelvic pain (adjusted RR, 1.62), stomach ulcers (adjusted RR, 1.72), spastic colon (adjusted RR, 3.62), and frequent indigestion, diarrhea, or constipation (adjusted RR, 1.30). Psychological IPV was as strongly associated with the majority of adverse health outcomes as was physical IPV. Conclusions: Psychological IPV has significant physical health consequences. To reduce the range of health consequences associated with IPV, clinicians should screen for psychological forms of IPV as well as physical and sexual IPV.

Using objective physical activity measures with youth: how many days of monitoring are needed?

Abstract: Purpose The purpose of this study was to establish the minimal number of days of monitoring required for accelerometers to assess usual physical activity in children. Methods A total of 381 students (189 M, 192 F) wore a CSA 7164 uniaxial accelerometer for seven consecutive days. To examine age-related trends students were grouped as follows: Group I: grades 1-3 (N = 92); Group II: grades 4-6 (N = 98); Group III: grades 7-9 (N = 97); Group IV: grades 10-12 (N = 94). Average daily time spent in moderate-to-vigorous physical activity (MVPA) was calculated from minute-by-minute activity counts using the regression equation developed by Freedson et al. (1997). Results Compared with adolescents in grades 7 to 12, children in grades 1 to 6 exhibited less day-to-day variability in MVPA behavior. Spearman-Brown analysts indicated that between 4 and 5 d of monitoring would be necessary to a achieve a reliability of 0.80 in children, and between 8 and 9 d of monitoring would be necessary to achieve a reliability of 0.80 in adolescents. Within all grade levels, the 7-d monitoring protocol produced acceptable estimates of daily participation in MVPA (R = 0.76 (0.71-0.81) to 0.87 (0.84-0.90)). Compared with weekdays, children exhibited significantly higher levels of MVPA on weekends, whereas adolescents exhibited significantly lower levels of MVPA on weekends. Principal components analysis revealed two distinct time components for MVPA during the day for children (early morning, rest of the day), and three distinct time components for MVPA during the day for adolescents (morning, afternoon, early evening). Conclusions These results indicate that a 7-d monitoring protocol provides reliable estimates of usual physical activity behavior in children and adolescents and accounts for potentially important differences in weekend versus weekday activity behavior as well as differences in activity patterns within a given day.

Risk factors for adolescent substance abuse and dependence: data from a national sample

Abstract: A national household probability sample of 4,023 adolescents aged 12 to 17 years was interviewed by telephone about substance use, victimization experiences, familial substance use, and posttraumatic reactions to identify risk factors for Diagnostic and Statistical Manual of Mental Disorders--(4th ed.; American Psychiatric Association, 1994) defined substance abuse/dependence. Age and ethnicity data were available for 3,907 participants. Major findings were (a) adolescents who had been physically assaulted, who had been sexually assaulted, who had witnessed violence, or who had family members with alcohol or drug use problems had increased risk for current substance abuse/dependence; (b) posttraumatic stress disorder independently increased risk of marijuana and hard drug abuse/dependence; and (c) when effects of other variables were controlled, African Americans, but not Hispanics or Native Americans, were at approximately 1/3 the risk of substance abuse/dependence as Caucasians.

Microbial biofilms in intertidal systems: an overview

Abstract: Intertidal marine systems are highly dynamic systems which are characterized by periodic #uctuations in environmental parameters. Microbial processes play critical roles in the remineralization of nutrients and primary production in intertidal systems. Many of the geochemical and biological processes which are mediated by microorganisms occur within microenvironments which can be measured over micrometer spatial scales. These processes are localized by cells within a matrix of extracellular polymeric secretions (EPS), collectively called a ‘microbial bio"lma. Recent examinations of intertidal systems by a range of investigators using new approaches show an abundance of bio"lm communities. The purpose of this overview is to examine recent information concerning the roles of microbial bio"lms in intertidal systems. The microbial bio"lm is a common adaptation of natural bacteria and other microorganisms. In the #uctuating environments of intertidal systems, bio"lms form protective microenvironments and may structure a range of microbial processes. The EPS matrix of bio"lm forms sticky coatings on individual sediment particles and detrital surfaces, which act as a stabilizing anchor to bu!er cells and their extracellular processes during the frequent physical stresses (e.g., changes in salinity and temperature, UV irradiation, dessication). EPS is an operational de"nition designed to encompass a range of large microbially-secreted molecules having widely varying physical and chemical properties, and a range of biological roles. Examinations of EPS using Raman and Fourier-transform infared spectroscopy, and atomicforce microscopy suggest that some EPS gels possess physical and chemical properties which may hasten the development of sharp geochemical gradients, and contribute a protective e!ect to cells. Bio"lm polymers act as a sorptive sponge which binds and concentrates organic molecules and ions close to cells. Concurrently, the EPS appear to localize extracellular enzyme activities of bacteria, and hence contribute to the e$cient biomineralization of organics. At larger spatial scales, the copious secretion of speci"c types of EPS by diatoms on the surfaces of

Frequency and Correlates of Intimate Partner Violence by Type: Physical, Sexual, and Psychological Battering

Abstract: OBJECTIVES: This study estimated the frequency and correlates of intimate partner violence by type (physical, sexual, battering, or emotional abuse) among women seeking primary health care. METHODS: Women aged 18 to 65 years who attended family practice clinics in 1997 and 1998 took part. Participation included a brief in-clinic survey assessing intimate partner violence. Multiple polytomous logistic regression was used to assess correlates of partner violence by type. RESULTS: Of 1401 eligible women surveyed, 772 (55.1%) had experienced some type of intimate partner violence in a current, most recent, or past intimate relationship with a male partner; 20.2% were currently experiencing intimate partner violence. Among those who had experienced partner violence in any relationship, 77.3% experienced physical or sexual violence, and 22.7% experienced nonphysical abuse. Alcohol and/or drug abuse by the male partner was the strongest correlate of violence. CONCLUSIONS: Partner substance abuse and intimate partner violence in the woman's family of origin were strong risk factors for experiencing violence. Efforts to universally screen for partner violence and to effectively intervene to reduce the impact of such violence on women's lives must be a public health priority.

Re-examining the effects of psychological contract violations: unmet expectations and job dissatisfaction as mediators

Abstract: This research examines whether the relationships between psychological contract violations and three types of employee behavior (intention to quit, neglect of in-role job duties, and organizational citizenship behaviors) are mediated by unmet expectations and job dissatisfaction. Using a sample of over 800 managers from a wide variety of research sites, this study tests for mediator effects using both hierarchical regression analyses and structural equation modelling. The results suggest that unmet expectations and job dissatisfaction do partially mediate such relationships. Copyright © 2000 John Wiley & Sons, Ltd.

Tat-specific cytotoxic T lymphocytes select for SIV escape variants during resolution of primary viraemia.

Abstract: Human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infections are characterized by early peaks of viraemia that decline as strong cellular immune responses develop Although it has been shown that virus-specific CD8-positive cytotoxic T lymphocytes (CTLs) exert selective pressure during HIV and SIV infection, the data have been controversial Here we show that Tat-specific CD8-positive T-lymphocyte responses select for new viral escape variants during the acute phase of infection We sequenced the entire virus immediately after the acute phase, and found that amino-acid replacements accumulated primarily in Tat CTL epitopes This implies that Tat-specific CTLs may be significantly involved in controlling wild-type virus replication, and suggests that responses against viral proteins that are expressed early during the viral life cycle might be attractive targets for HIV vaccine development

Determinants of leisure time physical activity in rural compared with urban older and ethnically diverse women in the United States

Abstract: STUDY OBJECTIVE Determinants of leisure time physical activity (LTPA) in rural middle aged and older women of diverse racial and ethnic groups are not well understood. This study examined: (1) urban-rural differences in LTPA by sociodemographic factors, (2) urban-rural differences in LTPA determinants, and (3) the pattern of relations between LTPA determinants and LTPA. DESIGN A modified version of the sampling plan of the Behavioral Risk Factor Surveillance Survey (BRFSS) was used. Zip codes were selected with 20% or more of each of the following race/ethnic groups: African American, American Indian/Alaskan Native (AI/AN), and Hispanic. A comparison group of white women were also surveyed using standard BRFSS techniques. PARTICIPANTS Rural (n=1242) and urban (n=1096) women aged 40 years and older from the US Women9s Determinants Study. MAIN RESULTS Rural women, especially Southern and less educated women, were more sedentary than urban women. Rural women reported more personal barriers to LTPA, cited caregiving duties as their top barrier (compared with lack of time for urban women), and had greater body mass indices. Rural women were less likely to report sidewalks, streetlights, high crime, access to facilities, and frequently seeing others exercise in their neighbourhood. Multivariate correlates of sedentary behaviour in rural women were AI/AN and African American race, older age, less education, lack of enjoyable scenery, not frequently seeing others exercise, greater barriers, and less social support (p CONCLUSIONS Rural and urban women seem to face different barriers and enablers to LTPA, and have a different pattern of determinants, thus providing useful information for designing more targeted interventions.

The role of microbes in accretion, lamination and early lithification of modern marine stromatolites

Abstract: For three billion years, before the Cambrian diversification of life, laminated carbonate build-ups called stromatolites were widespread in shallow marine seas. These ancient structures are generally thought to be microbial in origin and potentially preserve evidence of the Earth's earliest biosphere. Despite their evolutionary significance, little is known about stromatolite formation, especially the relative roles of microbial and environmental factors in stromatolite accretion. Here we show that growth of modern marine stromatolites represents a dynamic balance between sedimentation and intermittent lithification of cyanobacterial mats. Periods of rapid sediment accretion, during which stromatolite surfaces are dominated by pioneer communities of gliding filamentous cyanobacteria, alternate with hiatal intervals. These discontinuities in sedimentation are characterized by development of surface films of exopolymer and subsequent heterotrophic bacterial decomposition, forming thin crusts of microcrystalline carbonate. During prolonged hiatal periods, climax communities develop, which include endolithic coccoid cyanobacteria. These coccoids modify the sediment, forming thicker lithified laminae. Preservation of lithified layers at depth creates millimetre-scale lamination. This simple model of modern marine stromatolite growth may be applicable to ancient stromatolites.

Systematic errors in digital image correlation caused by intensity interpolation

Abstract: Recently, digital image correlation as a tool for surface defor- mation measurements has found widespread use and acceptance in the field of experimental mechanics. The method is known to reconstruct displacements with subpixel accuracy that depends on various factors such as image quality, noise, and the correlation algorithm chosen. How- ever, the systematic errors of the method have not been studied in detail. We address the systematic errors of the iterative spatial domain cross- correlation algorithm caused by gray-value interpolation. We investigate the position-dependent bias in a numerical study and show that it can lead to apparent strains of the order of 40% of the actual strain level. Furthermore, we present methods to reduce this bias to acceptable lev- els. © 2000 Society of Photo-Optical Instrumentation Engineers. (S0091-3286(00)00911-9)

Managing Images in Different Cultures: A Cross-National Study of Color Meanings and Preferences

Abstract: Color is an integral part of products, services, packaging, logos, and other collateral and can be an effective means of creating and sustaining brand and corporate images in customers’ minds. Through an eight-country study, the authors explore consumers’ preferences for different colors and color combinations. The results show cross-cultural patterns of both similarity and dissimilarity in color preferences and color meaning associations. When subjects are asked to match colors for a product logo, some color combinations suggest a consistency in meaning, whereas other combinations suggest colors whose meanings are complementary. The authors discuss implications for managing color to create and sustain brand and corporate images across international markets.

Advances in Two-Dimensional and Three-Dimensional Computer Vision

Abstract: The foundations of two- and three-dimensional image correlation, as well as recent developments, are described in detail. The versatility and robustness of these methods are illustrated through application examples from diverse areas including fracture mechanics, biomechanics, constitutive property measurement in complex materials, model verification for large, flawed structures and nondestructive evaluation. A detailed description of experimental and data-reduction procedures is presented for the application of the two-dimensional image-correlation method to thin-sheet mixed-mode I/II fracture studies, local crack-closure measurements using optical microscopy and the measurement of constitutive properties. Application examples using three-dimensional image correlation include profiling of components for reverse engineering and manufacturing and the measurement of full-field surface deformation during wide cracked panel tensile tests for verification of buckling and crack-growth models. Results from nearly sixteen years of use have demonstrated that both two-dimensional and three-dimensional image-correlation methods are robust and accurate tools for deformation measurements in a variety of applications. The range of uses for the two-and three-dimensional image-correlation methods is growing rapidly as scientists and engineers begin to understand their true capabilities.

Sports Participation and Health-Related Behaviors Among US Youth

Abstract: Objective To examine the relationship between sports participation and health-related behaviors among high school students. Design Cross-sectional design using data from the 1997 Centers for Disease Control and Prevention Youth Risk Behavior Survey. Participants A nationally representative sample of 14,221 US high school students. Main Outcome Measures Prevalence of sports participation among males and females from 3 ethnic groups and its associations with other health behaviors, including diet, tobacco use, alcohol and illegal drug use, sexual activity, violence, and weight loss practices. Results Approximately 70% of male students and 53% of female students reported participating on 1 or more sports teams in school and/or nonschool settings; rates varied substantially by age, sex, and ethnicity. Male sports participants were more likely than male nonparticipants to report fruit and vegetable consumption on the previous day and less likely to report cigarette smoking, cocaine and other illegal drug use, and trying to lose weight. Compared with female nonparticipants, female sports participants were more likely to report consumption of vegetables on the previous day and less likely to report having sexual intercourse in the past 3 months. Among white males and females, several other beneficial health behaviors were associated with sports participation. A few associations with negative health behaviors were observed in African American and Hispanic subgroups. Conclusion Sports participation is highly prevalent among US high school students, and is associated with numerous positive health behaviors and few negative health behaviors.

Geometric phases for mixed states in interferometry.

Abstract: We provide a physical prescription based on interferometry for introducing the total phase of a mixed state undergoing unitary evolution, which has been an elusive concept in the past. We define the parallel transport condition that provides a connection form for obtaining the geometric phase for mixed states. The expression for the geometric phase for mixed state reduces to well known formulas in the pure state case when a system undergoes noncyclic and unitary quantum evolution.

Issue Framing and Public Opinion on Government Spending

Abstract: The issue of government spending provides an interesting context for testing issue-framing effects in American public opinion. Competing partisan elites clearly portray the spending issue in different ways: Republicans tend to focus on broad, general appeals, while Democrats aim at more specific forms of programmatic expenditures. Their differing arguments undoubtedly arise because the varied issue frames generate different kinds of responses. This study uses data from the 1992 CPS National Election Study to examine the preceding hypothesis. The results from the empirical analysis show that public opinion on government spending does, in fact, vary markedly with the presentation of the issue. This framing effect is powerful enough to induce individual-level opinion change. And, framing effects arise because varying presentations of the government-spending issue activate different sets of influences on citizens' issue attitudes. These findings have broad implications concerning both the magnitude of framing effects and the explicitly political nature of the issue-framing process. his article examines issue-framing effects in American public opinion. A single social problem can be characterized and discussed in several different ways. The specific terms used to "create" a political issue out of a social problem have a strong effect on the nature and degree of popular agreement with the various sides of that issue. An obvious implication is that politicians will attempt to define, or "frame," issues in ways that maximize support for their own positions. The issue of government spending provides an interesting context for testing these ideas about issue framing. Republicans and Democrats clearly portray the use of public expenditures in different ways. Republicans focus on broad, general appeals (e.g., "government spending must be cut!"), while Democrats aim at more specific forms of programmatic outlays (e.g., "It is important to fund medical care for the elderly!"). Their differing arguments undoubtedly arise because the varied issue frames-in this case, the general presentation versus the more specific portrayal of government spending-generate different kinds of responses. In this study, I will employ public opinion data from the 1992 CPS National Election Study to examine the preceding hypothesis, along with its causes and consequences. Public opinion on government spending does, in fact, vary markedly with the presentation of the issue. And framing effects arise because varying presentations of the government-spending issue activate different sets of influences on citizens' attitudes. These findings contribute to scholarly understanding of issue framing in several ways. First, they demonstrate that significant framing effects exist outside the laboratory. The effects occur in settings that approximate the everyday world of political discourse, on an issue that is central to the predominant lines of partisan cleavage in contemporary American politics. Second, the analysis shows that framing does not merely produce different distributions of public opinion; instead, varying issue presentations can ac-

Compromised HOXA5 function can limit p53 expression in human breast tumours

Abstract: Expression of the p53 gene protects cells against malignant transformation1,2. Whereas control of p53 degradation has been a subject of intense scrutiny, little is known about the factors that regulate p53 synthesis1,2. Here we show that p53 messenger RNA levels are low in a large proportion of breast tumours. Seeking potential regulators of p53 transcription, we found consensus HOX binding sites3,4 in the p53 promoter5. Transient transfection of Hox/HOXA5 activated the p53 promoter. Expression of HOXA5 in epithelial cancer cells expressing wild-type p53, but not in isogenic variants lacking the p53 gene6, led to apoptotic cell death. Moreover, breast cancer cell lines and patient tumours display a coordinate loss of p53 and HOXA5 mRNA and protein expression. The HOXA5 promoter region was methylated in 16 out of 20 p53-negative breast tumour specimens. We conclude that loss of expression of p53 in human breast cancer may be primarily due to lack of expression of HOXA5.

Working In Retirement: The Antecedents Of Bridge Employment And Its Consequences For Quality Of Life In Retirement

Abstract: In this study, we used a continuity theory of aging to examine bridge employment. Excellent health, organizational tenure, and having working spouses and dependent children were positively associat...