University of North Carolina at Wilmington

About: University of North Carolina at Wilmington is a education organization based out in Wilmington, North Carolina, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 3329 authors who have published 6797 publications receiving 186308 citations.

Positive and negative reinforcement: Should the distinction be preserved?

Abstract: Michael (1975) reviewed efforts to classify reinforcing events in terms of whether stimuli are added (positive reinforcement) or removed (negative reinforcement). He concluded that distinctions in these terms are confusing and ambiguous. Of necessity, adding a stimulus requires its previous absence and removing a stimulus its previous presence. Moreover, there is no good basis, either behavioral or physiological, that indicates the involvement of distinctly different processes, and on these grounds he proposed that the distinction be abandoned. Despite the cogency of Michael's analysis, the distinction between positive and negative reinforcement is still being taught. In this paper, we reconsider the issue from the perspective of 30 years. However, we could not find new evidence in contemporary research and theory that allows reliable classification of an event as a positive rather than a negative reinforcer. We conclude by reiterating Michael's admonitions about the conceptual confusion created by such a distinction.

Priming Media Stereotypes Reduces Support for Social Welfare Policies: The Mediating Role of Empathy

Abstract: Two experiments involving White participants tested the influence of media-based priming of Black stereotypes on support for government policy that assisted Black versus White persons-in-need. Experiment 1 showed that priming the "Black criminal" stereotype through exposure to photographs of Blacks looting after Hurricane Katrina reduced policy support for Black evacuees-in-need but did not influence support responses toward White evacuees-in-need. Experiment 2 showed that priming the "promiscuous Black female" stereotype through exposure to sexual rap music reduced policy support for a Black pregnant woman-in-need but did not influence support responses toward a White pregnant woman-in-need. Further tests of mediated moderation demonstrated that in both experiments, the interactive influence of priming Black stereotypes and race of persons-in-need on policy support was mediated by empathic responding.

Improving Stroke Caregiver Readiness for Transition From Inpatient Rehabilitation to Home.

Abstract: Purpose As the population ages, older adults are more often living with functional limitations from chronic illnesses, such as stroke, and require assistance. Because stroke occurs suddenly, many stroke family caregivers in the United States are unprepared to assume caregiving responsibilities post-discharge. Research is limited on how family members become ready to assume the caregiving role. In this study, we developed a theoretical model for improving stroke caregiver readiness and identifying gaps in caregiver preparation. Design and methods We interviewed 40 stroke family caregivers caring for 33 stroke survivors during inpatient rehabilitation and within 6 months post-discharge for this grounded theory study. Data were analyzed using dimensional analysis and constant comparative techniques. Results Caregivers identified critical areas where they felt unprepared to assume the caregiving role after discharge from inpatient rehabilitation. Steps to improve preparation include (a) conducting a risk assessment of the patient and caregiver; (b) identifying and prioritizing gaps between the patient's needs and caregiver's commitment and capacity; and (c) developing a plan for improving caregiver readiness. Implications The model presented provides a family-centered approach for identifying needs and facilitating caregiver preparation. Given recent focus on improving care coordination, care transitions, and patient-centered care to help improve patient safety and reduce readmissions in this population, this research provides a new approach to enhance these outcomes among stroke survivors with family caregivers.

Does the skeleton of a sponge provide a defense against predatory reef fish

Abstract: Sponge tissue often contains two structural components in high concentrations: spicules of silica, and refractory fibers of protein (spongin). Some terrestrial plants contain analogous structures, siliceous inclusions and refractory lignins, that have been demonstrated to deter herbivory. We performed feeding experiments with predatory reef fish to assess the deterrent properties of the structural components of three common Caribbean demosponges, Agelas clathrodes, Ectyoplasia ferox, and Xestospongia muta. The concentrations of spicules and spongin in the tissues varied widely between the three species, but when assayed at their natural volumetric concentrations, neither spicules (all three species assayed) nor the intact spiculated spongin skeleton (A. clathrodes and X. muta assayed) deterred feeding by reef fish in aquarium or field assays using prepared foods of a nutritional quality similar to, or higher than, that of sponge tissue. Spicules deterred feeding in aquarium assays when incorporated into prepared foods of a nutritional quality lower than that of sponge tissue (15-19 times less protein), but spiculated spongin skeleton was still palatable, even in prepared foods devoid of measurable protein, and even though spicules embedded in spongin were oriented in their natural conformation. Based on comparisons of the nutritional qualities of the tissues of the three sponge species and of the prepared foods, sponge tissue would have to be much lower in food value (5 times less protein or lower) for spicules to provide an effective defense, and spicules in combination with the spongin skeleton would be unlikely to provide an effective defense regardless of the nutritional quality of the tissue. Unlike terrestrial plants, marine sponges may use silica and refractory fibers solely for structural purposes.