Showing 1731 - 1740 of 2039 Items
Date: 2011-03-01
Creator: Tess Chakkalakal
Access: Open access
Date: 2012-09-17
Creator: Takahito Watanabe
Hiroshi Ochiai
Tetsushi Sakuma
Hadley W. Horch
Naoya, Hamaguchi
Taro Nakamura
Tetsuya Bando
Hideyo Ohuchi
Takashi Yamamoto
Sumihare Noji
Taro Mito
Access: Open access
- Hemimetabolous, or incompletely metamorphosing, insects are phylogenetically relatively basal and comprise many pests. However, the absence of a sophisticated genetic model system, or targeted gene-manipulation system, has limited research on hemimetabolous species. Here we use zinc-finger nuclease and transcription activator-like effector nuclease technologies to produce genetic knockouts in the hemimetabolous insect Gryllus bimaculatus. Following the microinjection of mRNAs encoding zinc-finger nucleases or transcription activator-like effector nucleases into cricket embryos, targeting of a transgene or endogenous gene results in sequence-specific mutations. Up to 48% of founder animals transmit disrupted gene alleles after zinc-finger nucleases microinjection compared with 17% after microinjection of transcription activator-like effector nucleases. Heterozygous offspring is selected using mutation detection assays that use a Surveyor (Cel-I) nuclease, and subsequent sibling crosses create homozygous knockout crickets. This approach is independent from a mutant phenotype or the genetic tractability of the organism of interest and can potentially be applied to manage insect pests using a non-transgenic strategy. Ā© 2012 Macmillan Publishers Limited. All rights reserved.
Date: 2015-05-01
Creator: Mary A. Rogalski
Access: Open access
Date: 2017-12-01
Creator: Anne E. McBride
Access: Open access
- Candida albicans, a common commensal fungus, can cause disease in immunocompromised hosts ranging from mild mucosal infections to severe bloodstream infections with high mortality rates. The ability of C. albicans cells to switch between a budding yeast form and an elongated hyphal form is linked to pathogenicity in animal models. Hyphal-specific proteins such as cell-surface adhesins and secreted hydrolases facilitate tissue invasion and host cell damage, but the specific mechanisms leading to asymmetric protein localization in hyphae remain poorly understood. In many eukaryotes, directional cytoplasmic transport of messenger RNAs that encode asymmetrically localized proteins allows efficient local translation at the site of protein function. Over the past two decades, detailed mechanisms for polarized mRNA transport have been elucidated in the budding yeast Saccharomyces cerevisiae and the filamentous fungus Ustilago maydis. This review highlights recent studies of RNA-binding proteins in C. albicans that have revealed intriguing similarities to and differences from known fungal mRNA transport systems. I also discuss outstanding questions that will need to be answered to reach an in-depth understanding of C. albicans mRNA transport mechanisms and the roles of asymmetric mRNA localization in polarized growth, hyphal function, and virulence of this opportunistic pathogen.
Date: 2017-01-01
Creator: Sarah Harmon
Access: Open access
- An author might read other written works to polish their own writing skill, just as a painter might analyze other paintings to hone their own craft. Yet, either might also visit the theatre, listen to a piece of music, or otherwise experience the world outside their particular discipline in search of creative insight. This paper explores one example of how a computational system might rely on what they have learned from analyzing another distinct form of expression to produce creative work. Specifically, the system presented here extracts semantic meaning from an input text and uses this knowledge to generate ambient music. An independent measures experiment was conducted to provide a preliminary assessment of the system and direct future work.
Date: 2021-06-01
Creator: Tom Ichibha
Allison L. Dzubak
Jaron T. Krogel
Valentino R. Cooper
Fernando A., Reboredo
Access: Open access
- CrI3 has recently been shown to exhibit low-dimensional, long-range magnetic ordering from few layers to single layers of CrI3. The properties of CrI3 bulk and few-layered systems are uniquely defined by a combination of short-range intralayer and long-range interlayer interactions, including strong correlations, exchange, and spin-orbit coupling. Unfortunately, both the long-range van der Waals interactions, which are driven by dynamic, many-body electronic correlations, and the competing strong intralayer correlations, present a formidable challenge for the local or semilocal mean-field approximations employed in workhorse electronic structure approaches like density-functional theory. In this paper we employ a sophisticated many-body approach that can simultaneously describe long- and short-range correlations. We establish that the fixed-node diffusion Monte Carlo (FNDMC) method reproduces the experimental interlayer separation distance of bulk CrI3 for the high-temperature monoclinic phase with a reliable prediction of the interlayer binding energy. We subsequently employed the FNDMC results to benchmark the accuracy of several density-functional theory exchange-correlation approximations.
Date: 2013-11-18
Creator: Stephen M. Majercik
Access: Open access
- In the Particle Swarm Optimization (PSO) algorithm, the expense of evaluating the objective function can make it difficult, or impossible, to use this approach effectively; reducing the number of necessary function evaluations would make it possible to apply the PSO algorithm more widely. Many function approximation techniques have been developed that address this issue, but an alternative to function approximation is function conservation. We describe GREEN-PSO (GR-PSO), an algorithm that, given a fixed number of function evaluations, conserves those function evaluations by probabilistically choosing a subset of particles smaller than the entire swarm on each iteration and allowing only those particles to perform function evaluations. The "surplus" of function evaluations thus created allows a greater number of particles and/or iterations. In spite of the loss of information resulting from this more parsimonious use of function evaluations, GR-PSO performs as well as, or better than, the standard PSO algorithm on a set of six benchmark functions, both in terms of the rate of error reduction and the quality of the final solution.
Date: 2013-12-01
Creator: Crystal Hall
Access: Open access
- The Venetian poet and librettist Giulio Strozzi (1583 -1652) spent much of his career glorifying he Serenissima through a series of theatrical pieces. His only epic poem, the Venetia edificata (1621, 1624), while ostensibly a celebration of the republic, shows a level of commitment to alileo Galilei (1564 -1643) and to Galileo's science that is unique among poets of the time, enetian or otherwise. It is the apex of Strozzi's artistic project to incorporate Galileo's discoveries nd texts into poetic works. The Venetia edificata also represents the culmination of a fifteen-year ffort to gain patronage from the Medici Grand Dukes in Florence. While the first, incomplete ersion is dedicated to the Venetian Doge, the second, finished version is dedicated to Grand DukeFerdinando II de' Medici of Florence. More than a decade after Galileo's departure from the eneto to Florence, Strozzi cites from Galileo's early works, creates a character inspired by Galileo, ncorporates the principles of Galileo's science into the organizing structure of the poem, and nswers one of Galileo's loudest complaints about Torquato Tasso's Jerusalem Delivered (1581). trozzi's strategies both in writing the Venetia edificata and in seeking patronage for it underscore he ambivalent response to Galileo in contemporary poetry.
Date: 2014-10-01
Creator: Erik Nelson
John C. Withey
Derric Pennington
Joshua J. Lawler
Access: Open access
- We determine the effect of the US Endangered Species Actās Critical Habitat designation on land use change from 1992 to 2011. We find that the rate of change in developed land (constructed material) and agricultural land is not significantly affected by Critical Habitat designation. Therefore, Sections 7 and 9 of the Endangered Species Act do not appear to be more heavily applied in lands designated as Critical Habitat areas versus lands within listed speciesā ranges, but without critical habitat designation. Further, there does not appear to be any extraordinary conservation activity in critical habitat areas; for example, environmental non-profits and land trusts do not appear to be concentrating activity in these areas. Before we conclude that the opportunity cost of Critical Habitat designation is negligible we need to examine the land management impacts of designation.
Date: 2009-01-01
Creator: Aviva Briefel
Access: Open access