Faculty Scholarship

Showing 311 - 320 of 733 Items

Destabilization of cortical dendrites and spines by BDNF

Date: 1999-01-01

Creator: Hadley Wilson Horch, Alex Krüttgen, Stuart D. Portbury, Lawrence C. Katz

Access: Open access

Particle-mediated gene transfer and two-photon microscopy were used to monitor the behavior of dendrites of individual cortical pyramidal neurons coexpressing green fluorescent protein (GFP) and brain-derived neurotrophic factor (BDNF). While the dendrites and spines of neurons expressing GFP alone grew modestly over 24-48 hr, coexpressing BDNF elicited dramatic sprouting of basal dendrites, accompanied by a regression of dendritic spines. Compared to GFP-transfected controls, the newly formed dendrites and spines were highly unstable. Experiments utilizing Trk receptor bodies, K252a, and overexpression of nerve growth factor (NGF) demonstrated that these effects were mediated by secreted BDNF interacting with extracellular TrkB receptors. Thus, BDNF induces structural instability in dendrites and spines, which, when restricted to particular portions of a dendritic arbor, may help translate activity patterns into specific morphological changes.


Deciphering the bacterial glycocode: Recent advances in bacterial glycoproteomics

Date: 2013-02-01

Creator: Scott A. Longwell, Danielle H. Dube

Access: Open access

Bacterial glycoproteins represent an attractive target for new antibacterial treatments, as they are frequently linked to pathogenesis and contain distinctive glycans that are absent in humans. Despite their potential therapeutic importance, many bacterial glycoproteins remain uncharacterized. This review focuses on recent advances in deciphering the bacterial glycocode, including metabolic glycan labeling to discover and characterize bacterial glycoproteins, lectin-based microarrays to monitor bacterial glycoprotein dynamics, crosslinking sugars to assess the roles of bacterial glycoproteins, and harnessing bacterial glycosylation systems for the efficient production of industrially important glycoproteins. © 2012 Elsevier Ltd.


A nuclear narrative: Robert Oppenheimer, autobiography, and public authority

Date: 2010-12-01

Creator: David K. Hecht

Access: Open access



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.


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.


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.


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.


Modeling multiple ecosystem services, biodiversity conservation, commodity production, and tradeoffs at landscape scales

Date: 2009-02-01

Creator: Erik Nelson, Guillermo Mendoza, James Regetz, Stephen Polasky, Heather, Tallis, D. Richard Cameron, Kai M.A. Chan, Gretchen C. Daily, Joshua Goldstein

Access: Open access

Nature provides a wide range of benefits to people. There is increasing consensus about the importance of incorporating these "ecosystem services" into resource management decisions, but quantifying the levels and values of these services has proven difficult. We use a spatially explicit modeling tool, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST), to predict changes in ecosystem services, biodiversity conservation, and commodity production levels. We apply InVEST to stakeholder-defined scenarios of land-use/land-cover change in the Willamette Basin, Oregon. We found that scenarios that received high scores for a variety of ecosystem services also had high scores for biodiversity, suggesting there is little tradeoff between biodiversity conservation and ecosystem services. Scenarios involving more development had higher commodity production values, but lower levels of biodiversity conservation and ecosystem services. However, including payments for carbon sequestration alleviates this tradeoff. Quantifying ecosystem services in a spatially explicit manner, and analyzing tradeoffs between them, can help to make natural resource decisions more effective, efficient, and defensible. © The Ecological Society of America.


Cross-cultural temperamental differences in infants, children, and adults in the United States of America and Finland

Date: 2012-04-01

Creator: Larissa M. Gaias, Katri Räikkönen, Niina Komsi, Maria A. Gartstein, Philip A., Fisher, Samuel P. Putnam

Access: Open access

Cross-cultural differences in temperament were investigated between infants (n=131, 84 Finns), children (n=653, 427 Finns), and adults (n=759, 538 Finns) from the United States of America and Finland. Participants from both cultures completed the Infant Behavior Questionnaire, Childhood Behavior Questionnaire and the Adult Temperament Questionnaire. Across all ages, Americans received higher ratings on temperamental fearfulness than Finnish individuals, and also demonstrated higher levels of other negative affects at several time points. During infancy and adulthood, Finns tended to score higher on positive affect and elements of temperamental effortful control. Gender differences consistent with prior studies emerged cross-culturally, and were found to be more pronounced in the US during childhood and in Finland during adulthood. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.


Exuberant and inhibited toddlers: Stability of temperament and risk for problem behavior

Date: 2008-03-01

Creator: Cynthia A. Stifter, Samuel Putnam, Laudan Jahromi

Access: Open access

Temperament, effortful control, and problem behaviors at 4.5 years were assessed in 72 children classified as exuberant, inhibited, and low reactive as 2-year-olds. Exuberant toddlers were more positive, socially responsive to novel persons, less shy, and rated as having more problem behaviors, including externalizing and internalizing behaviors, than other children as preschoolers. Two forms of effortful control, the ability to delay a response and the ability to produce a subdominant response, were associated with fewer externalizing behaviors, whereas expressing more negative affect (relative to positive/neutral affect) when disappointed was related to more internalizing behaviors. Interaction effects implicated high levels of unregulated emotion during disappointment as a risk factor for problem behaviors in exuberant children. © 2008 Cambridge University Press.