Showing 971 - 980 of 2039 Items
A Bayesian hierarchical mixture model with continuous-time Markov chains to capture bumblebee foraging behavior
Date: 2021-01-01
Creator: Max Thrush Hukill
Access: Open access
- The standard statistical methodology for analyzing complex case-control studies in ethology is often limited by approaches that force researchers to model distinct aspects of biological processes in a piecemeal, disjointed fashion. By developing a hierarchical Bayesian model, this work demonstrates that statistical inference in this context can be done using a single coherent framework. To do this, we construct a continuous-time Markov chain (CTMC) to model bumblebee foraging behavior. To connect the experimental design with the CTMC, we employ a mixture model controlled by a logistic regression on the two-factor design matrix. We then show how to infer these model parameters from experimental data using Markov chain Monte Carlo and interpret the results from a motivating experiment.
Narrative painting and visual gossip at the early-twentieth-century royal academy
Date: 2009-06-01
Creator: Pamela Fletcher
Access: Open access
- Narrative paintings of modern life were immensely popular at the Royal Academy from the 1850s well into the early twentieth century. Perfectly suited to the Academy's culture of conversation, the pictures invited viewers to respond to the scenes as if they were real life situations, and gossip about the depicted characters as if they were real people. While such responses were routinely derided by critics as evidence of the public's lack of aesthetic sophistication, they offer tantalizing glimpses of the pictures' social lives. This article argues that taking gossip seriously as a mode of engagement with art both amplifies our understanding of the meanings, functions, and pleasures of narrative painting, and suggests specific connections between exhibition culture and the meanings of pictures. Using the richly documented reception of the 'problem pictures' of the 1910s and 1920s as the primary evidence, this article establishes a taxonomy of gossipy modes of engagement with narrative painting, and argues that gossiping about pictures allowed for the performance of individual identity, the creation of social and artistic groups, and connected public and private understandings of the world.
The Role of Social Media for Knowledge Sharing and Collaboration in Distributed Teams
Creator: Nicole Ellison
Matthew Weber
Access: Open access
- Social media are providing a medium through which individuals are reshaping how they do many things – finding romantic partners, providing social support, grieving for loved ones, even buying mundane items like toothpaste. They are also reshaping organizations – the way they function, the relationships they contain, and the ways organizations interact with external stakeholders. In this paper, we consider the changes that social media have introduced to organizational knowledge-sharing practices. We believe the social and technical affordances of social media create new challenges for organizations and necessitate research examining the ways in which: (1) technological affordances impact knowledge sharing within and between teams, (2) interpersonal and relationship development processes shape knowledge sharing among distributed team members and their individual social networks, and (3) organizational social networks influence knowledge sharing among distributed team members.
A nuclear narrative: Robert Oppenheimer, autobiography, and public authority
Date: 2010-12-01
Creator: David K. Hecht
Access: Open access
Preparing for and managing change: Climate adaptation for biodiversity and ecosystems
Date: 2013-11-01
Creator: Bruce A. Stein
Amanda Staudt
Molly S. Cross
Natalie S. Dubois
Carolyn, Enquist
Roger Griffis
Lara J. Hansen
Jessica J. Hellmann
Joshua J. Lawler
Access: Open access
- The emerging field of climate-change adaptation has experienced a dramatic increase in attention as the impacts of climate change on biodiversity and ecosystems have become more evident. Preparing for and addressing these changes are now prominent themes in conservation and natural resource policy and practice. Adaptation increasingly is viewed as a way of managing change, rather than just maintaining existing conditions. There is also increasing recognition of the need not only to adjust management strategies in light of climate shifts, but to reassess and, as needed, modify underlying conservation goals. Major advances in the development of climate-adaptation principles, strategies, and planning processes have occurred over the past few years, although implementation of adaptation plans continues to lag. With ecosystems expected to undergo continuing climate-mediated changes for years to come, adaptation can best be thought of as an ongoing process, rather than as a fixed endpoint. © The Ecological Society of America.
The (Far) Backstory of the U.S.-Colombia Free Trade Agreement
Date: 2013-10-10
Creator: Stephen Meardon
Access: Open access
- In two pairs of episodes, first in 1824 and 1846 and then in 1892 and 1935, similar U.S.-Colombia trade agreements or their enabling laws were embraced first by protectionists and then by free traders. The history of the episodes supports the view that although political institutions exist to curb de facto political power, such power may be wielded to undo the institutions’ intended effects. The doctrinal affinities and interests of political actors are more decisive determinants of the free-trade or protectionist orientation of trade agreements than the agreements’ texts or legal superstructures. The long delay from signing to passage of the current U.S.-Colombia Free Trade Agreement is another case in point.
Formation of oral and pharyngeal dentition in teleosts depends on differential recruitment of retinoic acid signaling
Date: 2010-09-01
Creator: Yann Gibert
Laure Bernard
Melanie Debiais-Thibaud
Franck Bourrat
Jean Stephane, Joly
Karen Pottin
Axel Meyer
Sylvie Retaux
David W. Stock
William R. Jackman
Pawat Seritrakul
Gerrit Begemann
Vincent Laudet
Access: Open access
- One of the goals of evolutionary developmental biology is to link specific adaptations to changes in developmental pathways. The dentition of cypriniform fishes, which in contrast to many other teleost fish species possess pharyngeal teeth but lack oral teeth, provides a suitable model to study the development of feeding adaptations. Here, we have examined the involvement of retinoic acid (RA) in tooth development and show that RA is specifically required to induce the pharyngeal tooth developmental program in zebrafish. Perturbation of RA signaling at this stage abolished tooth induction without affecting the development of tooth-associated ceratobranchial bones. We show that this inductive event is dependent on RA synthesis from aldh1a2 in the ventral posterior pharynx. Fibroblast growth factor (FGF) signaling has been shown to be critical for tooth induction in zebrafish, and its loss has been associated with oral tooth loss in cypriniform fishes. Pharmacological treatments targeting the RA and FGF pathways revealed that both pathways act independently during tooth induction. In contrast, we find that in Mexican tetra and medaka, species that also possess oral teeth, both oral and pharyngeal teeth are induced independently of RA. Our analyses suggest an evolutionary scenario in which the gene network controlling tooth development obtained RA dependency in the lineage leading to the cypriniforms. The loss of pharyngeal teeth in this group was cancelled out through a shift in aldh1a2 expression, while oral teeth might have been lost ultimately due to deficient RA signaling in the oral cavity. © FASEB.
Oakeshott, Berlin, and liberalism
Date: 2003-01-01
Creator: Paul Franco
Access: Open access
- This article compares the political philosophies of Michael Oakeshott and Isaiah Berlin, probably the two most important political philosophers in postwar Britain, who, strangely, had very little to do with one another during their illustrious careers. The article focuses on their respective critiques of rationalism and theories of liberal pluralism, arguing that Oakeshott provides the more consistent and philosophically satisfying account in both instances.
Modelling ecosystem services in terrestrial systems
Date: 2010-07-22
Creator: Erik J. Nelson
Gretchen C. Daily
Access: Open access
- Over the past few decades, a multi-disciplinary research community has documented the goods and services provided by ecosystems in specific sites scattered across the world. This research community has now begun to focus on creating methods and tools for mapping and valuing the ecosystem services produced on any landscape in the world. We describe some of these methods and tools and how they calculate and express ecosystem service provision and value on landscapes. We also describe methods for predicting landscape change. These predictions can be used by multi-ecosystem service models to assess potential changes and trade-offs in ecosystem service provision and values into the future. © 2010 Faculty of 1000 Ltd.
Who benefits? How interest-convergence shapes benefit-sharing and indigenous rights to sustainable livelihoods in Russia
Date: 2020-11-01
Creator: Maria S. Tysiachniouk
Laura A. Henry
Svetlana A. Tulaeva
Leah S. Horowitz
Access: Open access
- The paper examines interactions of oil companies and reindeer herders in the tundra of the Russian Arctic. We focus on governance arrangements that have an impact on the sustainability of oil production and reindeer herding. We analyze a shift in benefit-sharing arrangements between oil companies and Indigenous Nenets reindeer herders in Nenets Autonomous Okrug (NAO), Russia, as an evolution of the herders’ rights, defined as the intertwined co-production of legal processes, ideologies, and power relations. Semi-structured interviews, participant observation, and document analysis demonstrate that in NAO, benefit-sharing shifted from paternalism (dependent on herders’ negotiation skills) to company-centered social responsibility (formalized compensation rules). This shift was enabled by the adoption of a formal methodology for calculating income lost due to extractive projects and facilitated by the regional government’s efforts to develop reindeer-herding. While laws per se did not change, herders’ ability to access compensation and markets increased. This paper shows that even when ideologies of indigeneity are not influential, the use of existing laws and convergence of the government’s and Indigenous groups’ economic interests may shift legal processes and power relations toward greater rights for Indigenous groups.