Psychopharmacologists are interested in delay and probability discounting because the tendency to discount the value of future and uncertain rewards has been linked with drug dependency. However, ...relatively little is known about the long-term stability of discounting measures typically studied in clinical psychopharmacology. To evaluate the stability of discounting over a 3-month period, the authors compared points of subjective equality (indifference points) with those collected from the same subjects 3 months earlier. Seven delay periods, ranging from 1 week to 25 years, and 7 probability values, ranging from .95 to .05, were assessed in an undergraduate sample (
n
= 22, delay discounting;
n
= 18, probability discounting). The authors examined both differential stability (stability of individual differences) and absolute stability (stability of the group mean) of delay and probability discounting measures as well as their respective indifference points. The results demonstrate that standard delay and probability discounting parameters (e.g., hyperbolic
k
and area under the curve) had both differential stability and absolute stability across 3 months. Moreover, most indifference points in the delay and probability discounting tasks demonstrated both differential and absolute stability. All together, these results suggest that delay and probability parameters are stable enough to predict future behavior, such as substance abuse. Additional findings indicated that a hyperbolic function fitted the data better than an exponential function and that delay and probability discounting parameters were not significantly correlated.
Human conflict - from family feuds, to labor strikes, to national warfare - is an ever-present and universal social problem and the methods to manage it, a challenge for everyone, from average ...citizens to policymakers and social theorists. Using Conflict Theory will educate students about how, under what conditions, and why conflict erupts, and how it can be managed. It is a unique classroom book blending theory and practical application and the first to bridge for students the science of social theory and the art of practice. The authors extract from classical sociological theory (Marx, Dahrendorf, Weber, Durkheim, and Parsons), and interpret for the student how these theoretical perspectives have contributed to understanding social conflict (its sources, the causes of escalation and de-escalation of violence, the negotiations process). The perspectives of contemporary theorists (such as Randall Collins, James Coleman, Joseph Himes, Hubert Blalock) are also brought to bear on these questions.
Human conflict - from family feuds, to labor strikes, to national warfare - is an ever-present and universal social problem and the methods to manage it, a challenge for everyone, from average ...citizens to policymakers and social theorists. Using Conflict Theory will educate students about how, under what conditions, and why conflict erupts, and how it can be managed. It is a unique classroom book blending theory and practical application and the first to bridge for students the science of social theory and the art of practice. The authors extract from classical sociological theory (Marx, Dahrendorf, Weber, Durkheim, and Parsons), and interpret for the student how these theoretical perspectives have contributed to understanding social conflict (its sources, the causes of escalation and de-escalation of violence, the negotiations process). The perspectives of contemporary theorists (such as Randall Collins, James Coleman, Joseph Himes, Hubert Blalock) are also brought to bear on these questions.
Penicillium italicum (Blue mold) is a major postharvest disease of citrus. An alternative to controlling the disease is through the use of yeasts. The purpose of the present study was to screen ...effective yeast antagonists against P. italicum, isolated from soil, leaves, flowers, and citrus fruits, to assess the action mechanisms of the yeast isolates that were demonstrated to be effective for biocontrol, and to identify the most effective yeast isolates for the biocontrol of blue mold. The in vitro assays showed that six yeast strains inhibited up to 90% of the pathogen's mycelial growth. In vivo assays, evaluating the incidence of blue mold on sweet oranges, the strains ACBL-04, ACBL-05, ACBL-10 and ACBL-11 were effective, demonstrating the potential for the blue mold control when preventively applied, whereas the ACBL-08 strain showed a high potential to preventive and curative applications. Additional studies on the modes of action of these yeast strains showed that most of the evaluated yeast strains did not produce antifungal substances, in sufficient quantities to inhibit the pathogen growth. Competition for nutrients was not a biocontrol strategy used by the yeast strains. The ‘killer’ activity might be the main action mechanism involved in P. italicum biocontrol. This study indicated that the multiple modes of action against the pathogen presented by yeasts may explain why these strains provided P. italicum control under in vitro and in vivo conditions. However, further studies in future might be able to elucidate the ‘killer’ activity and its interaction with pathogen cells and the bioproduct production using Candida stellimalicola strains for control postharvest diseases.
•Candida stellimalicola isolate showed the best control to Penicillium italicum.•The preventive treatments of yeast isolates improve the biocontrol of blue mold.•Killer activity was found to be a common biocontrol mechanism by the yeast isolates.
The larger movement for racial equality in the United States has experienced considerable structural and ideological differentiation in the past decade, largely as a consequence of disagreement over ...tactics to be employed. Two direct‐action sub‐movements, the southern sit‐ins and the urban riots, best illustrate the divergence with the former committed to tactical nonviolence and the latter to violent means of effecting social change.
To regain the momentum lost through this differentiation, certain leaders must reorganize a major part of the black population around a tactical approach that acknowledges both the peculiar needs and temper of the potential protestors, and the nature and tolerance level of the system it seeks to change. Responding to these criteria, the approach may develop in the form of an extremely militant but basically nonviolent tactic of social disruption, combining all but the most violent techniques used to date by equal rights activists.
How and why do activists persist in their commitment to a social movement beyond its initial mobilization phase? How do they manage their commitments? What role does creativity play in helping them ...keep their peace commitment intact over the long term? These are questions explored in this study. Based on extensive interviews with thirty persistent peace activists, a theory of sustained commitment is developed. It encompasses how people become available for peace activism and how political and social contexts affect their willingness to join and stay. It also identifies important social and personal factors that help to sustain commitment. These include creating an activist identity, integrating peace work into everyday life, holding beliefs that sustain activism, feeling bonded to a peace group, cultivating opportunities for action, sharing a peace vision with other activists, and managing responsibilities, criticism, and burnout. Persistent peace activists are rational in selecting courses of action, but also creative in the way they fashion their lives, manage their commitments, avoid burnout, and design and carry out projects. This creativity is an important factor contributing to pacifist persistence, yet it is a topic that has been largely neglected in collective action research. The authors argue for a stronger emphasis on 'creative action' in future research about activists and how they sustain their commitment in the face of many odds.
Implicit theories of intelligence were investigated via surveys of exemplars of intelligence. Study 1 was a four-sample survey of famous exemplars. These diverse samples reported a similar set of ...popular exemplars, which clustered into five groups. These groups represented five types of intelligence: scientific, artistic, entrepreneurial, communicative, and moral intelligence. In Study 2, the minimal overlap of intelligence exemplars with those of fame, creativity, and wisdom refuted the possibility that exemplar reports are indiscriminate or solely a result of availability. In Study 3, knowledgeable judges rated the similarity of 50 famous persons to exemplars representing each type of intelligence. All five similarity ratings predicted exemplar popularities. In Study 4, where exemplar reports were not restricted to famous people, 31% were nonfamous (friends, family members, teachers, etc.). The results indicate that five implicit types of intelligence, each represented by highly available exemplars, play a role in people’s implicit theories.
How and why do activists persist in their commitment to a social movement beyond its initial mobilization phase? How do they manage their commitments? What role does creativity play in helping them ...keep their peace commitment intact over the long term?