Background There are sex differences in addiction behaviors. To develop a pre-clinical animal model to investigate this, the present study examined sex differences in sucrose taking and seeking using Long-Evans rats. Methods Five experiments were conducted using separate groups of subjects. The first two examined sucrose or saccharin preference in two-bottle home cage choice tests. Experiment three assessed sucrose intake in a binge model with sucrose available in home cage bottles. Experiments four and five utilized operant-based procedures. In experiment four rats responded for sucrose on fixed and progressive ratio (FR, PR) schedules of reinforcement over a range of concentrations of sucrose. A final component of experiment four was measuring seeking in the absence of sucrose challenged with the dopamine D1 receptor antagonist SCH23390. Experiment five assessed responding for water on FR and PR schedules of reinforcement. Results When accounting for body weight, female rats consumed more sucrose than water; but there was no sex difference in saccharin preference over a range of saccharin concentrations. When accounting for body weight, females consumed more sucrose than males in the binge model, and only females increased binge intake over 14 days of the study. Females responded at higher rates for sucrose under both FR and PR schedules of reinforcement. Females responded at higher rates in extinction (seeking); SCH23390 reduced sucrose seeking of both females and males. Females responded at higher rates for water on FR and PR schedules than males, although rates of responding were low and decreased over sessions. Conclusions Across bottle-choice, binge intake, and operant procedures, female Long-Evans rats consumed more sucrose and responded at higher rates for sucrose. Although females also responded more for water, the vigor of responding did not explain the consistent sex difference in sucrose taking and seeking. The sex difference in sucrose taking was also not explained by sweet preference, as there was no sex difference in saccharin preference. These data provide a pre-clinical model to further evaluate sex differences in addiction behaviors and manipulations designed to reduce them.
Building on an exercise that identified potential harms from simulated investigational releases of a population suppression gene drive for malaria vector control, a series of online workshops identified nine recommendations to advance future environmental risk assessment of gene drive applications.
Neural collapse is an emergent phenomenon in deep learning that was recently discovered by Papyan, Han and Donoho. We propose a simple unconstrained features model in which neural collapse also emerges empirically. By studying this model, we provide some explanation for the emergence of neural collapse in terms of the landscape of empirical risk.
Transaction cost and internalization theory offers that firm-specific transaction-cost factors determine firm-specific optimal levels of multinationality. Decision makers should prefer alignment with optimal levels of multinationality. Yet, some firms continuously misalign with their optimal levels of multinationality. We argue that having multiple preferences may explain these ‘misfit’ firms. Specifically, firms with international experience may develop an inertial preference for further international growth, along with their preference for efficiency/optimization. Hence, more internationally experienced firms with insufficient multinationality will increase their levels of multinationality in subsequent time periods to satisfy both preferences. However, growth preferences in more internationally experienced firms with excess multinationality will counter optimization preferences, reducing the likelihood of decreases to levels of multinationality in subsequent periods. We find support for these ideas in the context of 242 Japanese electrical appliance firms between 2011 and 2019 (1401 firm-year observations).
Dalea pogonathera A. Gray was collected as part of a project to determine if metabolites of the genus Dalea have potential for the treatment of human hookworm disease, based on earlier findings of very active materials in D. ornata. We report here the isolation, characterization, and results of ex vivo bioassays of a new chalcone pogonatheridin A (1), and three new prenylated flavanones (3, 6, and 12). The isolated known compounds, a chalcone (2), flavanones (4,5,7-11,13,14), and a flavan-3-ol (15), were also examined. Pogonatheridin A (1) reduced the survival of the adults of Ancylostoma ceylanicum hookworm by 12.5 % (50 μg/mL), while all other compounds showed very weak or no activity. The compounds were tested (50 μg/mL) for toxicity to healthy mammalian cells. Seven of them (2-8) showed > 98 % reduction in survival of splenocytes, while 1 was somewhat less toxic at 74.3 % reduction in survival. While metabolites of D. pogonathera did not show promise as potential anthelmintics for hookworm disease, the toxicity information is of interest, and the rich diversity of metabolites of Dalea spp. remains apparent.
Foreign subsidiaries face ‘institutional duality’ from competing parent-firm and host-country conformity pressures. However, international coalitions of firms experience pressures to conform from multiple parents, resulting in ‘institutional multiplicity.’ We argue that coalition members bargain and satisfice to agree upon goals and responses to external pressures. As institutional multiplicity increases, coalition responses are increasingly framed around simple threshold-type goals all members can agree upon. We test this idea in the context of international coalitions challenging biotechnology and organic chemistry patents of competitors in the United States Patent and Trademark Office's Patent Trial and Appeals Board. Our analysis includes 946 observations, and finds that larger coalitions with greater variance in member home-country patent enforcement institutions are more likely to pursue strategies that have a simple performance goal all members can agree upon: having a competitor's patent invalidated instead of a settlement. This relationship is further enhanced when coalition members have diverse levels of strategic interest, captured by variance in portions of coalition members' overall patent portfolios belonging to the same patent family as the disputed patent.
We combine monazite petrochronology with thermal modeling to evaluate the relative roles of crustal melting, surface denudation, and tectonics in facilitating ultrafast exhumation of the Nanga Parbat Massif in the western Himalayan syntaxis. Our results reveal diachronous melting histories between samples and a pulse of ultrafast exhumation (9 to 13 mm/year) that began ~1 Ma and was preceded by several million years of slower, but still rapid, exhumation (2 to 5 mm/year). Recent studies show that an exhumation pulse of similar timing and magnitude occurred in the eastern Himalayan syntaxis. A synchronous exhumation pulse in both Himalayan syntaxes suggests that neither erosion by rivers and/or glaciers nor a pulse of crustal melting was a primary trigger for accelerated exhumation. Rather, our results, combined with those of recent studies in the eastern syntaxis, imply that larger-scale tectonic processes impose the dominant control on the current tempo of rapid exhumation in the Himalayan syntaxes.
Mainstream images of “toddler” tend to serve a humorous purpose in mass media, most often presenting children of this age (18 months–3 years) as out-of-control. This assumed “barbaric” toddler promotes early childhood as a time for intervention, expecting adults to be the shapers of behavior and knowledge within discourses of social regulation which delineate possible childhoods. Within the Capitalocene, possible childhoods are inextricably linked to future adulthoods where this intervention is desired early to prepare children for future schooling and thus, future work to further industrial progress and consumption. This article revisits narrative, self-reflexive data from a larger study to identify and deconstruct mundane, acceptable teaching practices that promote the positioning of very young children as “lesser beings” through the constant control of children’s bodies, ideas, and subjectivities. Through this deconstruction of practice and in turn adult-child power relations, ruptures in habitual ways of knowing and teaching lead to a reimagining of toddlers’ actions in an effort to build counternarratives. Practices of disruption and resignification aim to challenge the positions of classroom subjects as they are continuously reproduced through discourses of development and the neoliberal agenda.
Implicit math = male stereotypes have been found in early childhood and are linked to girls’ disproportionate disengagement from math-related activities and later careers. Yet, little is known about how malleable children’s automatic stereotypes are, especially in response to brief interventions. In a sample of 336 six- to eleven-year-olds, we experimentally tested whether exposure to a brief story vignette intervention with either stereotypical, neutral, or counter-stereotypical content (three conditions: math = boy vs. neutral vs. math = girl) could change implicit math-gender stereotypes. Results suggested that children’s implicit math = male stereotypes were indeed responsive to brief stories that either reinforced or countered the widespread math = male stereotype. Children exposed to the counter-stereotypical stories showed significantly lower (and non-significant) stereotypes compared to children exposed to the stereotypical stories. Critically, exposure to stories that perpetuated math = male stereotypes significantly increased math-gender stereotypes over and above baseline, underscoring that implicit gender biases that are readily formed during this period in childhood and even brief exposure to stereotypical content can strengthen them. As a secondary question, we also examined whether changes in stereotypes might also lead to changes in implicit math self-concept. Evidence for effects on implicit self-concept were not statistically significant.
The Corporate Social Responsibility (CSR) efforts of brands impact consumers’ willingness to support them, yet consumers are generally skeptical about CSR communication. This empirical work uses three experimental studies to show that framing CSR messages in values-based terms (“It is our duty to engage in this CSR initiative”) enhances consumers’ brand attitudes by increasing perceived moralization and perceived commitment to the initiative. More interestingly, we show that this effect is reversed for highly formalistic consumers (those motivated by the duty to follow values, principles, and rules) who are opposed to the CSR initiative. We also show that in the long term, values-based frames can lead to higher perceived hypocrisy in the eyes of highly formalistic people if the firm does not live up to its lofty principles. This is the first paper to establish the link between values-based CSR communication, perceived moralization, perceived commitment, and brand attitudes. It also brings together the research streams on CSR communication and consumer ethical systems to show that though values-based framing of CSR is a high-return strategy for brands in terms of improved brand attitudes, it is also a high-risk strategy for firms targeting highly formalistic consumers.
Just a decade ago Vision and Change in Undergraduate Biology Education : A Call to Action was released, catalyzing several initiatives to transform undergraduate life sciences education. Among these was the Partnership for Undergraduate Life Sciences Education (PULSE), a national organization commissioned to increase the adoption of Vision and Change recommendations within academic life sciences departments. PULSE activities have been designed based on the recognition that life sciences departments and faculty are embedded within institutions of higher education which, similar to other large organizations, are complex systems composed of multiple, interconnected subsystems. The organizational change research suggests that effecting large-scale changes (e.g., undergraduate STEM education transformation) may be facilitated by applying systems thinking to change efforts. In this paper we introduce the approach of systems thinking as a professional development tool to empower individual STEM faculty to effect department-level transformation. We briefly describe a professional development experience designed to increase life sciences faculty members’ understanding of systems thinking, present evidence that faculty applied a systems thinking approach to initiate department-level change, and discuss the degree to which transformation efforts were perceived to be successful. Though focused on faculty in the life sciences, our findings are broadly transferable to other efforts seeking to effect change in undergraduate STEM education.
Introduction: In Rwanda, only 20% of sexually active unmarried youth use contraception as compared to 64% of married women. Adolescence is an important time of growth and development that often includes the initiation of sexual activity. Sexually active adolescents need support in accessing contraceptive services to prevent negative health outcomes. In sub-Saharan Africa, the adolescent population represents a large share of the total population and that proportion is predicted to expand over time. Adolescent contraceptive needs have largely been unmet, and with growing numbers, there is increased potential for more negative health sequelae. Due to the low use of contraception by adolescents in Rwanda, and the growing population of adolescents, this study aims to explore the perspectives of family planning providers and adult contraceptive users on adolescent contraceptive use. Inclusion of adult community members in the study is a unique contribution, as research on adolescent contraceptive use in sub-Saharan Africa relies primarily on perspectives from adolescent and family planning providers.Methods: This qualitative study in 2018 utilized 32 in-depth interviews with experienced users of modern contraceptive methods and eight focus group discussions with family planning providers. Respondents were from Musanze and Nyamasheke Districts, the districts with the highest and lowest modern contraceptive use, respectively. Thematic content analysis was conducted in Atlas.ti. Results: Stigma regarding premarital sex results in barriers to adolescent access to contraceptive services. Family planning providers do provide services to adolescents; however, they often recommend secondary abstinence, offer a limited method selection, and accentuate risks associated with sexual activity and contraceptive use. Providers do support adolescent clients by emphasizing the need for privacy, confidentiality, and expedient services, particularly through youth corners, which are spaces within health facilities designed to meet youth needs specifically. Contraceptive using adult female community members advocate for youth access to contraception, however mothers are mixed in their comfort with discussing sexual health with their own youth. Conclusion: To destigmatize premarital sexual activity, government efforts to initiate communication about this topic must occur at national and community levels with the goal of continued conversation within the family. The government should also train family planning providers and all health personnel interacting with youth on adolescent-friendly health services. Dialogue between community members and family planning providers about adolescent access to contraceptive services could also reduce barriers for adolescents due to community members' generally supportive views on adolescent contraceptive use. Efforts to engage adolescent caregivers in how to talk with youth about sex could also contribute to expanded use.
This research features a discourse analysis of two podcasts: the “Mobb Deep, Shook Ones, Pt. II” episode of Song Exploder and the “Rap on Trial” episode of Hidden Brain. We selected these podcasts through an abductive method of what we call “fortuitous listening” because of how they reveal community cultural wealth (CCW) through their descriptions of the creative process. Specifically, our study addressed two questions: (1) What does an examination of two Hip Hop podcast process texts reveal about CCW? (2) How could a discussion of the CCW that is revealed through descriptions of creative process inform literacy practices? Findings demonstrate how linguistic, familial, navigational, and aspirational capital exhibited in first-person descriptions of rap composition helped to showcase Hip Hop texts as what Bettina Love calls a “complex personhood” well-beyond simplified or stereotypical critiques. Because of how these process texts demonstrate the ways that Hip Hop feature Alim's ill-literacies criteria of being based on intimate, lived, and liberatory experiences, we posit them to be effective tools of cultural brokerage, particularly for educators wishing to enact Hip Hop-Based Education.
While there is evidence for the effects of positive psychology interventions (PPIs) in the Western world, we know little about their effects on Arab cultures. This review aimed to assess the effects of PPIs on well‐being and mental health across Arab countries. Systematic searches of randomised controlled trials (RCTs) and quasi‐experimental studies investigating PPIs in Arabia were conducted in six English and Arabic databases from the inception of positive psychology in 1998 to 28 February 2022. The quality of the studies was assessed using the Cochrane risk‐of‐bias tools. The protocol was published in the BMJ Open. Forty‐four studies from 10 Arab countries (n = 3598 participants) were included. Of these, 12 were RCTs and 32 were quasi‐experimental. The studies mainly focused on adults (73%) and healthy populations (86%). PPIs included mindfulness, positive thinking, strengths, hope, optimism, self‐compassion, positive traits, and multiple PPIs. Nearly all studies (91%) mentioned cultural adaptation; however, little detail was given. This is the first review in Arabia. PPIs appear to be effective for promoting well‐being and reducing mental health issues. However, there were some risks of bias concerns. Future research should include younger and clinical populations, using larger samples and providing more details about adaptation.
We describe studies of the thermal guanidine metathesis (TGM) reaction, a reversible transformation that results in exchange of N-substituents of the guanidine functional group. By comparing the effects of discrete structural variations, we find that steric congestion is an important factor in determining both the equilibrium guanidine composition and the reaction kinetics. The alkyl versus aryl nature of N-substitution also plays an essential role in the reaction rate, up to the point that minimal TGM reactivity is observed when the guanidine contains wholly alkyl substituents. Furthermore, we demonstrate that TGM occurs under thermodynamic control and present evidence that it proceeds by a dissociative mechanism, supported by direct observation of a carbodiimide intermediate.
In the summer of 2019, our research team collected fossil wood from a high alpine meadow situated in the southern Rocky Mountains of Colorado. The silicified plant remains date back more than 300 million years, long before the time when the modern Rocky Mountains were uplifted. A single scientific study of this site occurred nearly eight decades before our investigation and had focused on the taxonomic affinities of the plant remains. The specimens we collected resulted in a new scientific study of the site that included an updated explanation of how remnants of a Pennsylvanian-age lycopsid forest growing near sea level in the paleotropical belt became silicified fossils preserved in a high mountain meadow at a mid-latitude.
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