5,765 research outputs found
Complete data and statistical code for: Seeding roadsides is necessary but not sufficient for restoring native floral communities
No full textThe data files contain plant observations for 63 roadside sites observed during the time period of May-Aug of 2021. The Program R code here will read in and summarize those data, complete analyses needed to duplicate the results of the manuscript, and create visualizations used in publication. See readme file for more information.These data were collected in support of a Minnesota Department of Transportation funded study evaluating roadside plantings. The goal of our study was understand how roadside pollinator forage is affected by planting pollinator-friendly seed mixes in roadsides in Minnesota, USA. We used a field study of mixed-age roadside plantings to assess this flower diversity in roadsides planted with status quo non-native seed mixes to those planted with pollinator friendly, native seed mixes. We found that while these native seed mixes did increase the abundance of native flowers, the roadsides' flower communities of native and non-native seedmixes converged through time to grass dominated and unplanted colonizing species. This repository contains the complete datasets as a comma-separated-value files and Program R code necessary to replicate the data prep, exploration, analysis, and visualizations presented in the manuscript.Minnesota Department of TransportationNational Science Foundation Graduate Research Fellowship Program under Grant No. CON-75851, project 00074041Mitchell, Timothy S; Verhoeven, Michael R; Darst, Ashley L; Patterson, Cate; Snell-Rood, Emilie C. (2024). Complete data and statistical code for: Seeding roadsides is necessary but not sufficient for restoring native floral communities. Retrieved from the Data Repository for the University of Minnesota (DRUM), https://doi.org/10.13020/4jnq-d711
Butterflies do not alter oviposition or larval foraging in response to anthropogenic increases in sodium, Animal Behaviour (2019)
No full textRaw data associated with Mitchell, T. S., et al., Butterflies do not alter oviposition or larval foraging in response to anthropogenic
increases in sodium, Animal Behaviour (2019), https://doi.org/10.1016/j.anbehav.2019.06.01
W. F. Mitchell
No full textEarlier this year, an article was published in the News Bulletin
(February 2012) on the background of Captain Boyns Hedley
Hocking, a dentist who became one of the first casualties in the
bombing of Darwin in 1942. The author, W F Mitchell, has kindly
provided a summary of the 70th anniversary activities held in
Darwin in February 2012 to commemorate this significant event in
the Northern Territory?s historyDate:2012-09News Bulletin no. 413, p. 36 - 37
Marriage record of Mitchell, Hampton and James, Lula
No full textMarriage license for Hampton Mitchell and Lula James. S. Timothy Tice was the officiant
Tomographic image of melt storage beneath Askja Volcano, Iceland using local microseismicity
No full textWe use P wave and S wave arrivals from microseismic earthquakes to construct 3-D tomographic Vp and Vs images of the magma storage region beneath Askja's central volcano in the Northern Volcanic Zone of Iceland. A distinctive ellipsoidal low-velocity anomaly, with both Vp and Vsvelocities 8-12% below the background, is imaged at 6-11 km depth beneath the caldera. The presence of a shallow magma chamber is corroborated by geodetic and gravity studies. The small Vp/Vs anomaly suggests a lack of pervasive melt. We interpret this anomaly as a region of multiple sills, some frozen but hot, others containing partial melt. A second, smaller low-velocity anomaly beneath the main magma storage region may represent a magma migration pathway. This interpretation is supported by the close proximity to the anomaly of clusters of deep, magmatically induced earthquakes. However, the location and shape of this deep anomaly are poorly constrained by the current data set
An Alternative Reading of Feminist Criticism on S. Weir Mitchell
No full textThis dissertation represents a renewed look at nineteenth-century physician and author, S. Weir Mitchell. This includes a discussion of how his “rest cure” fits into the medical and cultural trends of his era as well as revisiting the academic responses to both him and his cure. Those in the academy who write on Mitchell today are primarily feminist critics who approach him through the study of women writers who were his patients, such as Virginia Woolf and Charlotte Perkins Gilman, among others. The dominant pathway here is through Gilman’s short story, “The Yellow Wallpaper” as well as other documents produced by Gilman herself. This fact has created a body of criticism touching Mitchell that is unfortunately misrepresentative of his true nature, motives, and ideologies, especially regarding women. Part of the problem is the monolithic nature of the criticism itself, which tends to reject, even undermine, dissenting voices.
Chapter one, S. Weir Mitchell, A Physician of the Moment for the Disease of a Moment, traces the history of nervousness, nervous exhaustion, and neurasthenia to provide a cultural background of these “diseases” as well as a backstory for the discussion of such elements within subsequent chapters. This chapter also provides a brief origin story of Mitchell’s rest cure.
Chapter two, Misunderstandings of S. Weir Mitchell’s Rest Cure, addresses Mitchell’s unfortunate legacy within the academy, especially with the birth of the feminist movement and the critical “re-discovery” of Gilman’s story, “The Yellow Wallpaper,” in the 1970’s and 80’s.
Chapter three, Misunderstandings of S. Weir Mitchell’s Rest Cure, Continued, extends the analysis of feminist criticism on Mitchell to the 1990s and beyond. The tone of this criticism is slightly more equitable toward Mitchell, yet a negative bias remains evident, even within the work of the most fastidious of feminist scholars.
Chapter four, The Unapotheosis of Charlotte Perkins Gilman, discusses some of the editorial errors made within the early academic editions of Gilman’s “The Yellow Wallpaper” that were uncovered by Julie Bates Dock in the 1990s. This chapter also revisits Gilman’s account of her interaction with Mitchell, accomplished primarily through reconsiderations of her autobiography and initial letter to Mitchell.
Chapter five, Baking Lies and Leaving Breadcrumbs, addresses Gilman’s relationships with others, including Mitchell, Ambrose Bierce, William Randolph Hearst, and W.D. Howells. This chapter traces Gilman’s “breadcrumbs”—documents painting herself as a victim within such relationships—which critics often use to construct narratives of further victimhood.
Chapter six, Cervetti’s Spurious Scholarship, offers a comparison between Nancy Cervetti’s biography, S. Weir Mitchell, 1829-1914: Philadelphia’s Literary Physician (2012) and Mitchell’s unpublished autobiography. As an English Professor, Cervetti’s work is a testament to the fact that the “contagion” of negativity toward Mitchell in the academy is yet ongoing
Substrate Influences Turtle Nest Temperature, Incubation Period, and Offspring Sex Ratio in the Field
No full textTemperature-dependent sex determination, where egg incubation temperature irreversibly determines offspring sex, is a common sex-determining mechanism in reptiles. Weather is the primary determinant of temperature in reptile nests, yet the effects of weather are mediated through the nest microhabitat selected by the mother (e.g., overstory canopy cover). One potentially important aspect of the nest microhabitat is the physical substrate used for nesting. However, the influence of substrate type on nest temperature and offspring sex determination has never been experimentally assessed in the field. We incubated eggs of Painted Turtles (Chrysemys picta) in three substrate types similar to those commonly selected for nesting within our study population. Within a single study site, we constructed pits, which we refilled with loam, sand, or gravel. Then, we created artificial nests in each substrate type, and randomly assigned eggs to a substrate treatment. Substrate type influenced nest temperature and soil moisture, and affected incubation duration, but no other phenotype measured beyond offspring sex ratios. The cooler loam yielded the most male-biased outcome. This finding illustrates the potential importance of nesting substrate as a component of nest-site choice and as a factor in modeling future nest temperature scenarios.This is a manuscript of an article published as Mitchell, Timothy S., and Fredric J. Janzen. "Substrate Influences Turtle Nest Temperature, Incubation Period, and Offspring Sex Ratio in the Field." Herpetologica 75, no. 1 (2019): 57-62. doi: 10.1655/0018-0831-75.1.57. Posted with permission.</p
Feasibility and design of a tertiary education entitlement in Australia
No full textOverview: This report to the Mitchell Institute presents the outcomes of modelling the potential costs of an income contingent loan (ICL) that would form a core element of a tertiary education entitlement, as proposed in the February 2015 Mitchell Institute paper Financing tertiary education in Australia – the reform imperative and rethinking student entitlements by Mitchell Professorial Fellow Peter Noonan and Mitchell Policy Analyst Sarah Pilcher.
This report, Feasibility and design of a tertiary education entitlement in Australia: Modelling and costing a universal income contingent loan, models the costs of a single income contingent loans scheme for higher education and vocational education and training (VET) students. It seeks to quantify the largely hidden subsidies involved in income contingent loans through unpaid debt and the difference between the rate at which debt is indexed and the costs to government of borrowing to finance student debt.
Feasibility and design of a tertiary education entitlement in Australia: Modelling and costing a universal income contingent loan has been prepared by Dr Timothy Higgins and Professor Bruce Chapman, two of Australia’s leading experts on the design of income contingent loans.
Background
Feasibility and design of a tertiary education entitlement in Australia presents the outcomes of various financial modelling of the potential costs of applying an income contingent loan scheme to include all tertiary education students in Australia. The modelling maps students’ projected incomes by qualification level, finding significant variation in lifetime incomes across VET and higher education qualifications.
At present, there are a range of different income contingent loan schemes operating in Australia’s higher education and VET sectors. Under such schemes, students are not required to pay the upfront cost of their course. Instead, they are able to take out a loan with the government and repay the loan through the taxation system once they enter the workforce and their incomes reach a certain threshold.
But these loans are not available to all students. In the VET system, those studying for Certificate III and most Certificate IV VET courses, for example, early childhood education, aged care, and hospitality, do not have access to an income contingent loan. These students must pay the cost of their course upfront – a potential barrier as fees for many of these courses are increasing.
The Mitchell Institute will draw on the Higgins and Chapman report to finalise its proposal for an integrated tertiary education funding system in Australia
Publicpension governance and performance : lessons for developing countries
No full textThe author examines the relationship between public sector pension plan performance and management practices to improve the design and governance of public pensions in developing countries. Understanding this relationship is important because better yields on public pension plan investment reduce the need for additional taxes to support retirees - and well-funded plans stand a better chance of paying promised benefits. The author's model relates investment returns on public pension assets, as well as plan funding status, to features characterizing the pension systems'governance structure and authority, using new data set on U.S. state and local public sector plans. The following findings stand out. The higher the fraction of retirees elected to the pension board, the stronger the negative effect on investment return in 1990, and the more variable the returns. Systems fared about the same whether they had in-house or external money managers, or independent performance analysis (even if the external managers were drawn from the top 10). But public pensions performed better when fund and actuarial computations were done by professional actuarial and investment counselors rather than relying on former or current employees to choose investment strategies. Social investment rules hurt public pension yields. Public pension plans which mandated that a certain portion of investments be director to instate projects generated much lower returns. The data show that many public pension systems funded their plans satisfactorily but others did not. The results show the following. Fiscal stress reduced stock funding ratios. Stock funding rates were lower, the higher the fraction of elected retirees and elected active workers represented on the pension system board. Stock funding ratios were higher when a system had in-house actuaries, when the board authorized benefit levels, and when board members had liability insurance. Stock funding rates were unaltered by state statutes guaranteering that benefits be guaranteed by law, or by legally set funding requirements, or by the state's ability to carry budget deficits from one year to the next. Nor did they vary when dedicated or special taxes were earmarked for pension revenue. Policymakers in developing countries can profit from the mistakes made and lessons learned by U.S. pension analysis. Although no single package of pension plan practices can optimize investment performance for all systems across all time periods, care must be taken when designing the regulatory and investment environment in which these plans operate. Developing countries should study the work of the U.S. Government Accounting Standards Board. The author discusses some of the complex issues that must be confronted when establishing funding norms for defined benefit pension plans in the public sector.ICT Policy and Strategies,Financial Intermediation,Economic Theory&Research,Pensions&Retirement Systems,Economic Stabilization
Influence of subinhibitory concentrations of protein-synthesis-inhibiting antibiotics on production and release of the pneumococcal virulence factor pneumolysin in vitro
No full textOBJECTIVE: Pneumolysin is an important virulence factor of Streptococcus pneumoniae with cytotoxic and proinflammatory activities released during growth and autolysis. At concentrations above the minimal inhibitory concentration, the protein-synthesis-inhibiting antibiotics erythromycin, clindamycin and rifampicin inhibit the production and/or release of virulence factors in various bacterial species. We investigated the influence of subinhibitory concentrations of these antibiotics on production and release of pneumolysin by S. pneumoniae strain D39.METHODS: The pneumococcal strain D39 was grown in broth and treated with antibiotics at a concentration of 1/32 of the respective minimal inhibitory concentration. Cytoplasmic and extracellular pneumolysin was measured by quantitative immunoblotting with recombinant pneumolysin as standard.RESULTS: The subinhibitory antibiotic concentrations evaluated did not affect bacterial growth. During logarithmic growth, production of pneumolysin was decreased by clindamycin, erythromycin and rifampicin by approximately 50% compared with untreated controls. The release of pneumolysin was decreased to a similar extent.CONCLUSION: A decrease in pneumolysin production by 50% probably has a moderate biological effect. We do not advocate the use of subinhibitory concentrations of antibiotics to modulate the expression of virulence factors during pneumococcal disease, particularly with regard to the risk of development of antibiotic resistance.</p
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