639 research outputs found
Protecting Systems of Nature and Gender: Ecofeminism in Barbara Kingsolver\u27s Prodigal Summer and Ruth Ozeki\u27s All Over Creation
Ecofeminism has permeated the disciplines of politics, philosophy, science, and literature – all of which are embedded in the fiction of Barbara Kingsolver’s Prodigal Summer and Ruth Ozeki’s All Over Creation. In this thesis, I consider the authors’ use of scientific evidence to engage readers with their rhetorical goals of protecting the systems of nature and gender. In the first chapter, I define the history of ecofeminist activism and how Kingsolver and Ozeki continue its tradition. The second chapter considers the parallels between biodiversity and cultural diversity within both Prodigal Summer and All Over Creation. In the final chapter, I analyze themes of motherhood, maternity, and fertility in each novel, specifically as they are impacted by toxic human behavior
S\'{e}rsic galaxy models in weak lensing shape measurement: model bias, noise bias and their interaction
Cosmic shear is a powerful probe of cosmological parameters, but its
potential can be fully utilised only if galaxy shapes are measured with great
accuracy. Two major effects have been identified which are likely to account
for most of the bias for maximum likelihood methods in recent shear measurement
challenges. Model bias occurs when the true galaxy shape is not well
represented by the fitted model. Noise bias occurs due to the non-linear
relationship between image pixels and galaxy shape. In this paper we
investigate the potential interplay between these two effects when an imperfect
model is used in the presence of high noise. We present analytical expressions
for this bias, which depends on the residual difference between the model and
real data. They can lead to biases not accounted for in previous calibration
schemes. By measuring the model bias, noise bias and their interaction, we
provide a complete statistical framework for measuring galaxy shapes with model
fitting methods from GRavitational lEnsing Accuracy Testing (GREAT) like
images. We demonstrate the noise and model interaction bias using a simple toy
model, which indicates that this effect can potentially be significant. Using
real galaxy images from the Cosmological Evolution Survey (COSMOS) we quantify
the strength of the model bias, noise bias and their interaction. We find that
the interaction term is often a similar size to the model bias term, and is
smaller than the requirements of the current and shortly upcoming galaxy
surveys.Comment: 11 pages, 3 figure
Measurement and Calibration of Noise Bias in Weak Lensing Galaxy Shape Estimation
Weak gravitational lensing has the potential to constrain cosmological
parameters to high precision. However, as shown by the Shear TEsting Programmes
(STEP) and GRavitational lEnsing Accuracy Testing (GREAT) Challenges, measuring
galaxy shears is a nontrivial task: various methods introduce different
systematic biases which have to be accounted for. We investigate how pixel
noise on the image affects the bias on shear estimates from a
Maximum-Likelihood forward model-fitting approach using a sum of co-elliptical
S\'{e}rsic profiles, in complement to the theoretical approach of an an
associated paper. We evaluate the bias using a simple but realistic galaxy
model and find that the effects of noise alone can cause biases of order 1-10%
on measured shears, which is significant for current and future lensing
surveys. We evaluate a simulation-based calibration method to create a bias
model as a function of galaxy properties and observing conditions. This model
is then used to correct the simulated measurements. We demonstrate that this
method can effectively reduce noise bias so that shear measurement reaches the
level of accuracy required for estimating cosmic shear in upcoming lensing
surveys.Comment: 12 pages, 4 figures, submitted to MNRA
Semiclassical Gravity in the Far Field Limit of Stars, Black Holes, and Wormholes
Semiclassical gravity is investigated in a large class of asymptotically
flat, static, spherically symmetric spacetimes including those containing
static stars, black holes, and wormholes. Specifically the stress-energy
tensors of massless free spin 0 and spin 1/2 fields are computed to leading
order in the asymptotic regions of these spacetimes. This is done for spin 0
fields in Schwarzschild spacetime using a WKB approximation. It is done
numerically for the spin 1/2 field in Schwarzschild, extreme
Reissner-Nordstrom, and various wormhole spacetimes. And it is done by finding
analytic solutions to the leading order mode equations in a large class of
asymptotically flat static spherically symmetric spacetimes. Agreement is shown
between these various computational methods. It is found that for all of the
spacetimes considered, the energy density and pressure in the asymptotic region
are proportional to 1/r^5 to leading order. Furthermore, for the spin 1/2 field
and the conformally coupled scalar field, the stress-energy tensor depends only
on the leading order geometry in the far field limit. This is also true for the
minimally coupled scalar field for spacetimes containing either a static star
or a black hole, but not for spacetimes containing a wormhole.Comment: 43 pages, 2 figures. Reference added, minor changes, PRD versio
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Dynamic Patterns of Transcript Abundance of Transposable Element Families in Maize.
Transposable Elements (TEs) are mobile elements that contribute the majority of DNA sequences in the maize genome. Due to their repetitive nature, genomic studies of TEs are complicated by the difficulty of properly attributing multi-mapped short reads to specific genomic loci. Here, we utilize a method to attribute RNA-seq reads to TE families rather than particular loci in order to characterize transcript abundance for TE families in the maize genome. We applied this method to assess per-family expression of transposable elements in >800 published RNA-seq libraries representing a range of maize development, genotypes, and hybrids. While a relatively small proportion of TE families are transcribed, expression is highly dynamic with most families exhibiting tissue-specific expression. A large number of TE families were specifically detected in pollen and endosperm, consistent with reproductive dynamics that maintain silencing of TEs in the germ line. We find that B73 transcript abundance is a poor predictor of TE expression in other genotypes and that transcript levels can differ even for shared TEs. Finally, by assessing recombinant inbred line and hybrid transcriptomes, complex patterns of TE transcript abundance across genotypes emerged. Taken together, this study reveals a dynamic contribution of TEs to maize transcriptomes
Operational Considerations for Oxygen Flammability Risks: Concentrated Oxygen Diffusion and Permeation Behaviors
Increased human spaceflight operations utilize oxygen concentrations that are frequently varied with use of concentrations up to 100 percent oxygen. Even after exiting a higher percentage oxygen environment, high oxygen concentrations can still be maintained due to material saturation and oxygen entrapment between barrier materials. This paper examines the material flammability concerns that arise from changing oxygen environments during spaceflight operations. We examine the time required for common spacecraft and spacesuit materials exposed to oxygen to return to reduced ignitability and flammability once removed from the increased concentration. Various common spacecraft materials were considered: spacecraft cabin environment foams, Extra Vehicular Mobility Unit materials and foams, Advanced Crew Escape Suit materials, and other materials of interest such as Cotton, Nomex^ HT90-40, and Tiburon Surgical Drape. This paper presents calculated diffusion coefficients derived from experimentally obtained oxygen transmission rates for the tested materials and the analytically derived times necessary for reduced flammability to be achieved based on NASA flammability criteria. Oxygen material saturation and entrapment scenarios are examined. Experimental verification data on oxygen diffusion in saturation scenarios are also presented and discussed. We examine how to use obtained data to address flammability concerns during operational planning to reduce the likelihood of fires while improving efficiency for procedures
A study of the environmental economic effect on implementing subsidies on alternatives to red meat
The rapidly increasing trend in meat consumption causes a great challenge for policy makers. With 20% of the individual’s total emissions originating in food consumption, this gives an area of opportunity in decreasing emissions through promoting dietary changes. This study investigates the effects on greenhouse gas emissions and net costs of subsidizing less emitting alternatives to red meat. A regression model is applied, attaining own-price and cross-price elasticities on which the rest of the calculations are based. It is found that cheese and chicken are counterproductive to the aim of decreasing emissions. The best result on emissions is found when subsidizing only seafood and eggs, while cutting the net costs in half. However, the small effect on emissions does not justify the costs of implementing the subsidy. We therefore suggest a combination with a tax on more emission intense goods
Identification and Validation of Small Molecules That Enhance Recombinant Adeno-associated Virus Transduction following High-Throughput Screens
ABSTRACT While the recent success of adeno-associated virus (AAV)-mediated gene therapy in clinical trials is promising, challenges still face the widespread applicability of recombinant AAV(rAAV). A major goal is to enhance the transduction efficiency of vectors in order to achieve therapeutic levels of gene expression at a vector dose that is below the immunological response threshold. In an attempt to identify novel compounds that enhance rAAV transduction, we performed two high-throughput screens comprising 2,396 compounds. We identified 13 compounds that were capable of enhancing transduction, of which 12 demonstrated vector-specific effects and 1 could also enhance vector-independent transgene expression. Many of these compounds had similar properties and could be categorized into five groups: epipodophyllotoxins (group 1), inducers of DNA damage (group 2), effectors of epigenetic modification (group 3), anthracyclines (group 4), and proteasome inhibitors (group 5). We optimized dosing for the identified compounds in several immortalized human cell lines as well as normal diploid cells. We found that the group 1 epipodophyllotoxins (teniposide and etoposide) consistently produced the greatest transduction enhancement. We also explored transduction enhancement among single-stranded, self-complementary, and fragment vectors and found that the compounds could impact fragmented rAAV2 transduction to an even greater extent than single-stranded vectors. In vivo analysis of rAAV2 and all of the clinically relevant compounds revealed that, consistent with our in vitro results, teniposide exhibited the greatest level of transduction enhancement. Finally, we explored the capability of teniposide to enhance transduction of fragment vectors in vivo using an AAV8 capsid that is known to exhibit robust liver tropism. Consistent with our in vitro results, teniposide coadministration greatly enhanced fragmented rAAV8 transduction at 48 h and 8 days. This study provides a foundation based on the rAAV small-molecule screen methodology, which is ideally used for more-diverse libraries of compounds that can be tested for potentiating rAAV transduction. IMPORTANCE This study seeks to enhance the capability of adeno-associated viral vectors for therapeutic gene delivery applicable to the treatment of diverse diseases. To do this, a comprehensive panel of FDA-approved drugs were tested in human cells and in animal models to determine if they increased adeno-associated virus gene delivery. The results demonstrate that particular groups of drugs enhance adeno-associated virus gene delivery by unknown mechanisms. In particular, the enhancement of gene delivery was approximately 50 to 100 times better with than without teniposide, a compound that is also used as chemotherapy for cancer. Collectively, these results highlight the potential for FDA-approved drug enhancement of adeno-associated virus gene therapy, which could result in safe and effective treatments for diverse acquired or genetic diseases
Student Voices Session / Moderator: Ed Vermue
Hear how objects-based pedagogy has shaped and positively impacted the educational experiences of students.
Jennifer Lin: English and East Asian StudiesUna Creedon-Carey: Medieval StudiesSarah Rose Lejeune: Book ArtsJulian Hirsch: ArchaeologyNathan Carpenter: Africatown Projec
The Sustained Effects of CBT Training on Therapist Competence and Patient Outcomes
The continued effectiveness of in-service psychological therapy training requires evaluation. This study assessed therapist competence and patient clinical outcome during cognitive behaviour therapy training and 12+ months post-training. Trainee competence was assessed using audio-recorded sessions rated on the Cognitive Therapy Scale Revised at the beginning (n = 33) and end of training (n = 45), and at least 12 months post-training (n = 45). Pre-to-posttreatment clinical outcome for trainees’ patients during the course (n = 360) and post-training (n = 360) was evaluated using standardised self-report measures. The relationship between therapist competence and patient outcomes was explored. Trainees achieved competence during training (100%, n = 45) and largely maintained competence post-training (84%, n = 38). Patients demonstrated pre-to-posttreatment effect sizes between 1.38 and 1.89 and reliable improvement exceeding 80% during and after training. Competence was not significantly associated with patient outcome. Trainees predominantly maintained competence and achieved good clinical outcomes post-training. Structured training and continued use of regular supervision possibly supported retention of competence
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