Showing 301 - 310 of 733 Items
Date: 2011-01-01
Creator: Belinda Kong
Access: Open access
Date: 2019-01-01
Creator: Thomas D. King, Justine E. Johnson, Jack R. Bateman
Access: Open access
- Transvection is an epigenetic phenomenon wherein regulatory elements communicate between different chromosomes in trans, and is thereby dependent upon the three-dimensional organization of the genome. Transvection is best understood in Drosophila, where homologous chromosomes are closely paired in most somatic nuclei, although similar phenomena have been observed in other species. Previous data have supported that the Drosophila genome is generally permissive to enhancer action in trans, a form of transvection where an enhancer on one homolog activates gene expression from a promoter on a paired homolog. However, the capacity of different genomic positions to influence the quantitative output of transvection has yet to be addressed. To investigate this question, we employed a transgenic system that assesses and compares enhancer action in cis and in trans at defined chromosomal locations. Using the strong synthetic eye-specific enhancer GMR, we show that loci supporting strong cis-expression tend to support robust enhancer action in trans, whereas locations with weaker cis-expression show reduced transvection in a fluorescent reporter assay. Our subsequent analysis is consistent with a model wherein the chromatin state of the transgenic insertion site is a primary determinant of the degree to which enhancer action in trans will be supported, whereas other factors such as locus-specific variation in somatic homolog pairing are of less importance in influencing position effects on transvection.
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.”
Date: 2010-08-01
Creator: Sedat H. Beis, Saikrishna Mukkamala, Nathan Hill, Jincy Joseph, Cirila, Baker, Bruce Jensen, Elizabeth A. Stemmler, M. Clayton Wheeler, Brian G. Frederick
Access: Open access
- Three lignins: Indulin AT, Lignoboost™, and Acetocell lignin, were characterized and pyrolyzed in a continuous-fed fast pyrolysis process. The physical and chemical properties of the lignins included chemical composition, heat content, ash, and water content. The distributed activation energy model (DAEM) was used to describe the pyrolysis of each lignin. Activation energy distributions of each lignin were quite different and generally covered a broad range of energies, typically found in lignins. Process yields for initial continuous-fed fast pyrolysis experiments are reported. Bio-oil yield was low, ranging from 16 to 22%. Under the fast pyrolysis conditions used, the Indulin AT and Lignoboost™ lignin yielded slightly more liquid product than the Acetocell lignin. Lignin kinetic parameters and chemical composition vary considerably and fast pyrolysis processes must be specified for each type of lignin.
Date: 2021-01-01
Creator: Allison Cooper, Fernando Nascimento, David Francis
Access: Open access
- This article presents a case study of Kinolab, a digital platform for the analysis of narrative film language. It describes the need for a scholarly database of clips focusing on film language for cinema and media studies faculty and students, highlighting recent technological and legal advances that have created a favorable environment for this kind of digital humanities work. Discussion of the project is situated within the broader context of contemporary developments in moving image annotation and a discussion of the unique challenges posed by computationally-driven moving image analysis. The article also argues for a universally accepted data model for film language to facilitate the academic crowdsourcing of film clips and the sharing of research and resources across the Semantic Web.
Date: 2016-08-18
Creator: Crystal Hall
Access: Open access
- A survey distributed in English and Italian to collect information about the intersection of the fields of Italian Studies and Digital Humanities. The goals are to describe the kinds of work being done by scholars in this space of intersection, identify successful professional pathways that combine methods or content from the two fields, and inform next steps for organizations that support this work. Results will be discussed at the Wellesley "State of the Discipline" event on October 1, 2016 and the MLA Roundtable on the topic, January 5, 2017. The survey is provided here in case other fields are interested in conducting similar work.
Date: 2017-09-01
Creator: David K. Hecht
Access: Open access
- Nuclear history always compels. Scholars (and readers) can immerse themselves in the existential threat posed by the atomic bomb and its successor weapons, the tantalizing prospect of carbon-free energy, or the study of a natural phenomenon deeply at odds with our everyday experience of the world. There is thus always something profound at stake when we write nuclear historyÂ-Â be it physical, economic or intellectual. And while it may seem that the end of the Cold War should have diminished the academic attention accorded to the subject, it actually just allowed the historiography to evolve. To the wealth of technical and political studies that once dominated nuclear history, we can now add a host of excellent cultural, environmental, literary and transnational studies. Those of us who entered the field shortly after the break-up of the Soviet Union have been able to follow these developments first-hand, from the initial uncertainty of where nuclear history would go without its original raison d'être to seeing the possibilities opened up in a post-Cold War world. The books under review here provide important and timely additions to this historiography. Luis A. Campos's Radium and the Secret Life provides a rigorous and compelling account of the uses of radium in early twentieth-century biology; Timothy J. Jorgensen's Strange Glow: The Story of Radiation offers an accessible and illuminating analysis of the benefits and risks of radiation. The books also make for a fascinating juxtaposition. They complement each other well, but also contain some intriguing differences that allow us to reflect on the nature of nuclear history in the early twenty-first century.
Date: 2013-04-12
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.
Date: 2013-10-01
Creator: Brendan Eliot Depue, Nick Ketz, Matthew V. Mollison, Erika Nyhus, Marie T. Banich, Tim Curran
Access: Open access
- Although investigations of memory and the dynamics of ERP components and neural oscillations as assessed through EEG have been well utilized, little research into the volitional nature of suppression over memory retrieval have used these methods. Oscillation analyses conducted on the Think/No-Think (TNT) task and volitional suppression of retrieval are of interest to broaden our knowledge of neural oscillations associated not only during successful memory retrieval but also when retrieval is unwanted or suppressed. In the current study, we measured EEG during a TNT task and performed ERP and EEG spectral power band analyses. ERP results replicated other researchers' observations of increases in 500-800 msec parietal effects for items where retrieval was instructed to be elaborated compared with being suppressed. Furthermore, EEG analyses indicated increased alpha (8-12 Hz) and theta (3-8 Hz) oscillations across parietal electrodes for items that were instructed to be suppressed versus those to be elaborated. Additionally, during the second half of the experiment (after repeated attempts at control), increases in theta oscillations were found across both frontal and parietal electrodes for items that were instructed to be suppressed and that were ultimately forgotten versus those ultimately remembered. Increased alpha power for items that were instructed to be suppressed versus elaborated may indicate reductions of retrieval attempts or lack of retrieval success. Increased theta power for items that were instructed to be suppressed versus elaborated may indicate increased or prolonged cognitive control to monitor retrieval events. © 2013 Massachusetts Institute of Technology.