Showing 1 - 10 of 733 Items
The H.C. Carey School of U.S. Currency Doctors: A "Subtle Principle" and its Progeny
Date: 2024-02-20
Creator: Stephen Meardon
Access: Open access
- Henry C. Carey led a school of post-Civil War U.S. currency doctors prescribing an “elastic currency,” expanding and contracting according to commercial needs. The problem for the Careyites was reconciling elasticity, which implied inconvertibility with gold, with the related aim of decentralized financial power. Careyite currency doctors included, among others, Wallace P. Groom, editor of the New York Mercantile Journal, and Henry Carey Baird, Carey’s own nephew and inheritor of his mantle. Their prescribed reform of the banking system featured a financial innovation that would remove superfluous currency from circulation while supplying what was needed. The innovation was an “interconvertible bond,” a debt instrument of the U.S. Treasury that was to be issued upon demand and redeemable for currency at the option of the holder. Its function was supposed to be like the mechanical governor of a steam engine, operating by a “subtle principle” that obviated human governing power and discretion. The Carey school’s prescription and its rationale remained salient up to the advent of the Federal Reserve System.
Lake water chemistry and local adaptation shape NaCl toxicity in Daphnia ambigua
Date: 2024-01-01
Creator: Mary Alta Rogalski, Elizabeth S Baker, Clara M Benadon
Access: Open access
- Increasing application of road deicing agents (e.g., NaCl) has caused widespread salinization of freshwater environments. Chronic exposure to toxic NaCl levels can impact freshwater biota at genome to ecosystem scales, yet the degree of harm caused by road salt pollution is likely to vary among habitats and populations. The background ion chemistry of freshwater environments may strongly impact NaCl toxicity, with greater harm occurring in ion-poor, soft water conditions. In addition, populations exposed to salinization may evolve increased NaCl tolerance. Notably, if organisms are adapted to their natal lake water chemistry, toxicity responses may also vary among populations in a given test medium. We examined how this evolutionary and environmental context may interact in shaping NaCl toxicity with a pair of laboratory reciprocal transplant toxicity experiments, using natural populations of the water flea Daphnia ambigua from three lakes differing in ion availability. The lake water environment strongly influenced NaCl toxicity in both trials. NaCl greatly reduced reproduction and r in lake water from a low-ion/ calcium-poor environment compared with water from both a calcium-rich lake and an ion-rich coastal lake. Daphnia from this coastal lake were most robust to the effects of NaCl. A significant population x environment interaction shaped survival in both trials, suggesting that local adaptation to the test waters used contributed to toxicity responses. Our findings that the lake water environment, adaptation to that environment, and adaptation to a focal contaminant may shape toxicity demonstrate the importance of considering environmental and biological complexity in mitigating pollution impacts.
In situ HCR in non-traditional arthropods
Date: 2024-01-25
Creator: Heather Bruce, Hadley Wilson Horch
Access: Open access
- Visualizing the expression of genes is a fundamental tool in molecular biology. Traditional colorimetric in situ hybridization using long RNA probes has been a staple for visualizing gene expression but has many drawbacks. In situ HCR v3.0, developed by Choi et. al. 2018, offers improvements over traditional in situs in nearly every aspect: probes can simply be ordered rather than painstakingly cloned and transcribed, which also makes them cost-effective; an HCR takes just three days to complete rather than five or more days; HCR is robust and works well for first-time users; and HCR probes can be multiplexed, allowing four to eight genes to be visualized in a single sample. HCR has been used successfully in many arthropods, including insects (Drosophila, Tribolium), crustaceans (Parhyale, Daphnia, Artemia), and chelicerates (Limulus horseshoe crab, Acanthoscurria tarantula). In this demo, you will learn how to design and order HCR probes as well as best practices for experimental design.
The Rubble of Culture: Debris of an Extinct Thought
Date: 2023-01-01
Creator: David A. Collings
Access: Open access
- Humanity now faces the possibility that it will become extinct over the next few decades or so. This is not simply a reality about the biological fate of the species; it also raises the prospect of thought’s own extinction. But what does it mean for thought that it, too, might disappear? Thought’s possible disappearance shatters the assumption, at work across all the institutions and disciplines of the West, that one version or another of thought is enduring and will survive. As it turns out, no familiar practice rests on a secure ground; under the sign of the terminus - the prospect of humanity’s extinction - each one is shattered and undone. The cultural legacy becomes a field of rubble. In dozens of short essays, this book moves through this field. It takes up a host of specific inheritances and traces how each is shattered and transformed by an extinct thought. It engages with religion, philosophy, history, literature, ethics, studies of political power and resistance, and depictions of humanity’s place in the nonhuman world. It reconsiders the emergence of capitalism and of biopower, the science of climate change, the import of mediation and technology, and philosophies of temporality. Moreover, it contends with many innovative waves of thought over the past two centuries, from German idealism to deconstruction, from psychoanalysis to queer theory, from decolonizing theory to Afropessimism, and from the critique of ideology to speculative realism. It concludes by assessing what it is like for thought, having confronted its extinction, to live on in this debris, to dance with its own oblivion.
“I Never Saw as Good a Nature Show Before”: Walt Disney, Environmental Education, and the True-Life Adventures
Date: 2022-01-01
Creator: Charles Dorn
Access: Open access
- Alongside Walt Disney’s animated movies, television programming, and theme parks, scholars have examined The Walt Disney Studios’ True-Life Adventures series of live-action nature documentary films for their impact on popular culture. Historians, however, have mostly overlooked the significance of the True-Life Adventures for student learning about the natural world. Amending this historiographical shortcoming, this essay examines Disney’s innovative approach to wildlife filmmaking, describes viewers’ reactions to the True-Life Adventures’ educational qualities, and investigates the Studios’ efforts to use the films to enter the education market. The study breaks new ground by analyzing seldom accessed documents preserved in theWalt Disney Archives both to reveal how students, teachers, and college and university faculty responded to the films and to examine the extension of the nature documentaries through related media.
Estimating the impact of Critical Habitat designation on the values of developed and undeveloped parcels (2nd version, current as of 7/29/2022)
Date: 2022-07-29
Creator: Saleh Mamun, Erik Nelson, Christoph Nolte
Access: Open access
- We use differences-in-differences (DD) estimators to measure the impact that Endangered Species Act (ESA)’s Critical Habitat (CH) rule had on developed and undeveloped parcel prices throughout the US between 2000 and 2019. In a national-level analysis we found that, on average, the price of parcels “treated” with CH were not statistically different than the prices of nearby parcels in listed species range space but not “treated” by CH. CH’s null impact on developed parcel prices is surprising given homeowner’s documented willingness to pay for property surrounded by protected open space. CH’s null impact on undeveloped parcel prices is surprising as previous research had indicated that the impact of CH on undeveloped parcel prices was negative due to the additional regulatory costs and development uncertainty the CH regulation imposes on land developers. When we used relevant subsets of CH areas to measure CH’s impact on parcel prices, we did occasionally find results that were consistent with expectations. We reach two conclusions. First, the impact of the economic impact of the CH rule, holding the impact of other ESA sections constant, cannot be reduced to a simple, consistent narrative. Second, CH’s relatively minor impact on parcel prices suggests that the rule does not have much regulatory “bite.”
Theta oscillations support active exploration in human spatial navigation
Date: 2022-11-15
Creator: Elizabeth R. Chrastil, Caroline Rice, Mathias Goncalves, Kylie N. Moore, Syanah C. Wynn, Chantal E. Stern, Erika Nyhus
Access: Open access
- Active navigation seems to yield better spatial knowledge than passive navigation, but it is unclear how active decision-making influences learning and memory. Here, we examined the contributions of theta oscillations to memory-related exploration while testing theories about how they contribute to active learning. Using electroencephalography (EEG), we tested individuals on a maze-learning task in which they made discrete decisions about where to explore at each choice point in the maze. Half the participants were free to make active decisions at each choice point, and the other half passively explored by selecting a marked choice (matched to active exploration) at each intersection. Critically, all decisions were made when stationary, decoupling the active decision-making process from movement and speed factors, which is another prominent potential role for theta oscillations. Participants were then tested on their knowledge of the maze by traveling from object A to object B within the maze. Results show an advantage for active decision-making during learning and indicate that the active group had greater theta power during choice points in exploration, particularly in midfrontal channels. These findings demonstrate that active exploration is associated with theta oscillations during human spatial navigation, and that these oscillations are not exclusively related to movement or speed. Results demonstrating increased theta oscillations in prefrontal regions suggest communication with the hippocampus and integration of new information into memory. We also found evidence for alpha oscillations during active navigation, suggesting a role for attention as well. This study finds support for a general mnemonic role for theta oscillations during navigational learning. © 2022
Brain activity patterns underlying memory confidence
Date: 2022-04-01
Creator: Syanah C. Wynn, Erika Nyhus
Access: Open access
- The primary aim of this review is to examine the brain activity patterns that are related to subjectively perceived memory confidence. We focus on the main brain regions involved in episodic memory: the medial temporal lobe (MTL), prefrontal cortex (PFC), and posterior parietal cortex (PPC), and relate activity in their subregions to memory confidence. How this brain activity in both the encoding and retrieval phase is related to (subsequent) memory confidence ratings will be discussed. Specifically, encoding related activity in MTL regions and ventrolateral PFC mainly shows a positive linear increase with subsequent memory confidence, while dorsolateral and ventromedial PFC activity show mixed patterns. In addition, encoding-related PPC activity seems to only have indirect effects on memory confidence ratings. Activity during retrieval in both the hippocampus and parahippocampal cortex increases with memory confidence, especially during high-confident recognition. Retrieval-related activity in the PFC and PPC show mixed relationships with memory confidence, likely related to post-retrieval monitoring and attentional processes, respectively. In this review, these MTL, PFC, and PPC activity patterns are examined in detail and related to their functional roles in memory processes. This insight into brain activity that underlies memory confidence is important for our understanding of brain–behaviour relations and memory-guided decision making. © 2022 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
Alpha modulation in younger and older adults during distracted
encoding
Date: 2022-06-01
Creator: Syanah C. Wynn, Erika Nyhus, Ole Jensen
Access: Open access
- To successfully encode information into long-term memory, we need top-down control to focus our attention on target stimuli. This attentional focus is achieved by the modulation of sensory neuronal excitability through alpha power. Failure to modulate alpha power and to inhibit distracting information has been reported in older adults during attention and working memory tasks. Given that alpha power during encoding can predict subsequent memory performance, aberrant oscillatory modulations might play a role in age-related memory deficits. However, it is unknown whether there are age-related differences in memory performance or alpha modulation when encoding targets with distraction. Here we show that both older and younger adults are able to encode targets paired with distractors and that the level of alpha power modulation during encoding predicted recognition success. Even though older adults showed signs of higher distractibility, this did not harm their episodic memory for target information. Also, we demonstrate that older adults only modulated alpha power during high distraction, both by enhancing target processing and inhibiting distractor processing. These results indicate that both younger and older adults are able to employ the same inhibitory control mechanisms successfully, but that older adults fail to call upon these when distraction is minimal. The findings of this study give us more insight into the mechanisms involved in memory encoding across the lifespan. © 2020 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
Feasibility and acceptability of an online mindfulness-based group intervention for adults with tic disorders
Date: 2021-12-01
Creator: Hannah E. Reese, W. Alan Brown, Berta J. Summers, Jin Shin, Grace, Wheeler, Sabine Wilhelm
Access: Open access
- Abstract: Background: Preliminary research suggests that a mindfulness-based treatment approach may be beneficial for adults with tic disorders. In the present study, we report on the feasibility, acceptability, safety, and symptomatic effect of a novel online mindfulness-based group intervention for adults with Tourette syndrome or persistent tic disorder. Data from this study will directly inform the conduct of a funded randomized controlled trial comparing the efficacy of this intervention to another active psychological intervention. Methods: One cohort of adults with Tourette syndrome participated in an 8-week online mindfulness-based group intervention. Measures of feasibility, acceptability, and safety were administered throughout and at posttreatment. Self-reported measures of mindfulness and clinician-rated measures of tic severity and impairment were administered at baseline and posttreatment. Results: Data on refusal, dropout rate, attendance, participant satisfaction, and safety suggest that this is a feasible and acceptable intervention. However, participant adherence to home practice was lower than anticipated. Mindfulness, tic severity, and tic-related impairment only modestly improved from baseline to posttreatment. Qualitative analysis of participant feedback revealed aspects of the intervention that were most helpful and also areas for improvement. Conclusions: Data suggest that although this is a feasible and acceptable intervention, it should be modified to enhance participant adherence, more successfully engage the target mechanism, and optimize outcomes. Trial registration: Clinicaltrials.gov registration #NCT03525626. Registered on 24 April 2018