A comparison of Mediterranean Gecko (Hemidactylus turcicus) populations in two temperate zone urban habitats

Urban ecosystems represent unique habitats that might be more or less suitable than natural systems for many species. The Mediterranean Gecko, Hemidactylus turcicus is a synanthropic species that has successfully colonized many urban and suburban areas outside its natural range. In the United States, H. turcicus has been found predominantly in southern states on exterior surfaces of buildings. We compared population density, demographics, and extent of dispersal of populations of H. turcicus at two anthropogenic sites in a temperate region of the United States. The University of Central Oklahoma (UCO) had higher building density and greater cover by anthropogenic surfaces and the Oklahoma City Zoo (ZOO) had lower building density and greater cover by vegetation. Mark and recapture sampling was conducted at UCO from 2006 to 2007 and during 2008 at ZOO. The sizes of the populations at the two sites were estimated using the Schnabel method and population densities were calculated using those estimates. Age class of captured animals, sex of adults, and gravid status of adult females were determined at both sites. We assumed that greater exterior wall surface area of individual buildings at UCO and greater land cover by anthropogenic surfaces might 1) reduce population density and 2) facilitate dispersal there relative to the ZOO. Population sizes and density in animals per ha of land and building cover and demographics were similar at the two sites. Population density per ha of building exterior wall area was higher at ZOO than at UCO. The higher density of animals on buildings, lower proportion of subadults in the population and lower maximum dispersal distance at ZOO suggest that successful diffusion dispersal might be limited at that site relative to UCO.     

Getting Active in the Gulf: Environmental Attitudes and Action Following Two Mississippi Coastal Disasters

The current study examined the impact of the Gulf Oil Spill and Hurricane Katrina, environmental attitudes, and environmental action among residents of the Mississippi Gulf Coast. The authors sought to determine if disaster impact, worry about the environment, or connection to nature was associated with environmental action following the oil spill and in general. We hypothesized that disaster impact and environmental attitudes would be significantly associated with environmental action. Surveys were administered to 1,108 individuals receiving mental health services in connection with the Gulf Oil Spill. Results indicated that disaster impact was correlated with environmental worry, connection to nature, and action. Additionally, environmental worry and connection to nature were significantly associated with action, as were the effects of Hurricane Katrina to a lesser degree. This study supplements the existing literature by examining environmental attitudes, disaster impact, and their association with environmental action following two disasters.     

Weighting for unequal selection probabilities in multilevel models

When multilevel models are estimated from survey data derived using multistage sampling, unequal selection probabilities at any stage of sampling may induce bias in standard estimators, unless the sources of the unequal probabilities are fully controlled for in the covariates. This paper proposes alternative ways of weighting the estimation of a two-level model by using the reciprocals of the selection probabilities at each stage of sampling. Consistent estimators are obtained when both the sample number of level 2 units and the sample number of level 1 units within sampled level 2 units increase. Scaling of the weights is proposed to improve the properties of the estimators and to simplify computation. Variance estimators are also proposed. In a limited simulation study the scaled weighted estimators are found to perform well, although non-negligible bias starts to arise for informative designs when the sample number of level 1 units becomes small. The variance estimators perform extremely well. The procedures are illustrated using data from the survey of psychiatric morbidity.     

Optimal sample coordination using controlled selection

Sample coordination maximizes or minimizes the overlap of two or more samples selected from overlapping populations. It can be applied to designs with simultaneous or sequential selection of samples. We propose a method for sample coordination in the former case. We consider the case where units are to be selected with maximum overlap using two designs with given unit inclusion probabilities. The degree of coordination is measured by the expected sample overlap, which is bounded above by a theoretical bound, called the absolute upper bound, and which depends on the unit inclusion probabilities. If the expected overlap equals the absolute upper bound, the sample coordination is maximal. Most of the methods given in the literature consider fixed marginal sampling designs, but in many cases, the absolute upper bound is not achieved. We propose to construct optimal sampling designs for given unit inclusion probabilities in order to realize maximal coordination. Our method is based on some theoretical conditions on joint selection probability of two samples and on the controlled selection method with linear programming implementation. The method can also be applied to minimize the sample overlap.     

Perceptions of teen motherhood in Australian adolescent females: Life-line or lifederailment

PurposeThe findings presented in this paper describe the beliefs and attitudes of three different groups of adolescent females about teen motherhood. These were elicited from a larger analysis that explored and theorized contraceptive pathways in a sample of young Australian women.MethodsA purposive sample of females aged 14 to 19 years was recruited from three distinct populations in the city of Perth, Western Australia: (1) never-pregnant; (2) pregnant-terminated; and (3) pregnant-continued. Grounded theory principles were used to analyze data generated from 69 semi-structured interviews conducted over a 21 month period (2006–2008).ResultsTwo categories that described teenagers’ attitudes to pregnancy and motherhood were elicited from the analysis. These explained the level of priority that teenagers placed on using contraception and postponing the transition to parenthood. The category labeled ‘life derailment’ represented how those who had never had a pregnancy or had terminated a pregnancy constructed teen motherhood as potentially restricting their personal, career and social transition to adulthood. The alternative category, ‘life-line’, reflected how those who continued with their pregnancy perceived teen motherhood as a positive and transformative experience that fostered personal growth.ConclusionsThe findings from this study contribute further insight into the complex nature of adolescent contraceptive use and pregnancy risk. The analysis has strengthened evidence of the critical role of self-perceptions of pregnancy and childbearing on teenagers’ fertility outcomes. It has also emphasized the broader life circumstances that shape these attitudes, intentions and related behavior. Strategies directed toward academic support and vocational skill development may broaden teenage girls’ perceived future options and achievement capacity, thus influencing key reproductive health outcomes.     

A MONTE CARLO COMPARISON OF ELLIPTICAL-THEORY AND OTHER TESTS FOR EQUALITY OF COVARIANCE MATRICES

A Monte Carlo study of the size and power of tests of equality of two covariance matrices is carried out. Tests based upon normality assumptions, elliptical distribution assumptions as well as distribution-free tests are compared. Samples are generated from normal, elliptical and non-elliptical populations. The elliptical-theory tests, in particular, have poor size properties for both elliptical distributions with moderate sample sizes and for non-elliptical distributions.     

Sexual assault while in the military: violence as a predictor of cardiac risk?

The purpose of this article is to determine whether known cardiac risk factors are more prevalent among women veterans who report having sustained sexual assault while in the military. We surveyed a random sample of 3,632 women veterans using Veterans Administration (VA) ambulatory care nationally. Obesity, smoking, problem alcohol use, sedentary lifestyle, and hysterectomy before age 40 were found to be more common in women reporting a history of sexual assault while in the military than in women without such history. An association between myocardial infarction and prior sexual assault history may be mediated in part by known cardiac risk factors.     

The components of family policy education

The study of family policy in the United States began relatively recently. The academic community increasingly has shown interest in this new policy arena. Much of the conceptual writing on family policy emerged from disciplines such as family studies, social work, political science, economics, and sociology. These academic units have recently modified their course curricula to include more family policy content. These family policy education efforts are discussed in this article. Specific suggestions are made concerning the development and content of family policy education, broader educational training for those who want to pursue a career in family policy, and future goals and directions for family policy education. She received her Ph. D. in Human Development and Family Studies from The Pennsylvania State University. Her research interests are in the family and health policy arenas, with particular focus on ethnically diverse populations. Her most recent research is on homeless children and mothers. She received her Ph.D. in Family Social Science from the University of Minnesota. Her teaching and research interests are workplace and family issues and family policy and impact analysis.