373 research outputs found
Vesuvianite From Pajsberg, Sweden, and the Role of Be In the Vesuvianite Structure
Vesuvianite from Pajsberg, Sweden contains about one atom of Mn, based on 50 cations per formula unit, and small amounts of Be, B, and As. Optical absorption analysis suggests that the Mn is predominantly or entirely trivalent. Crystal-structure analysis indicates that Mn is housed at the general octahedral site Y3, which exhibits only minor distortion from ideal octahedral symmetry. Arsenic is housed at Y2 and Z2, and the formula derived from electron microprobe and LA-ICP-MS analyses suggests minor substitution of Al for Si, also at Z2. Beryllium and B are at T1, between the edge-sharing trimers Y3Y2Y3, as is the case for B in the boron-dominant vesuvianite species wiluite. The total content at T1 is interpreted as 0.82Be, 0.34B, and 0.037Fe^(3+)
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Impacts of elevated atmospheric COā on nutrient content of important food crops.
One of the many ways that climate change may affect human health is by altering the nutrient content of food crops. However, previous attempts to study the effects of increased atmospheric CO2 on crop nutrition have been limited by small sample sizes and/or artificial growing conditions. Here we present data from a meta-analysis of the nutritional contents of the edible portions of 41 cultivars of six major crop species grown using free-air CO2 enrichment (FACE) technology to expose crops to ambient and elevated CO2 concentrations in otherwise normal field cultivation conditions. This data, collected across three continents, represents over ten times more data on the nutrient content of crops grown in FACE experiments than was previously available. We expect it to be deeply useful to future studies, such as efforts to understand the impacts of elevated atmospheric CO2 on crop macro- and micronutrient concentrations, or attempts to alleviate harmful effects of these changes for the billions of people who depend on these crops for essential nutrients
Three dimensional optic tissue culture and process
A process for artificially producing three-dimensional optic tissue has been developed. The optic cells are cultured in a bioreactor at low shear conditions. The tissue forms normal, functional tissue organization and extracellular matrix
Baker Center Journal of Applied Public Policy, Vol. III No. I
Welcome to the third issue of the Baker Center Journal for Applied PublicPolicy. I am pleased that this issue, as its predecessors, evidences the vibrancy of the Baker Centerās governance and public policy programs and makes a contribution to our collective understanding about a variety of policy issues currently being discussed in America. Relating to our system of governance, Jess Hale Jr. examines a proposal for a uniform state approach to reining in renegade presidential electors and Professor Glenn Reynolds reviews Jack Goldsmithās book The Terror Presidency: Law and Judgment Inside the Bush Administration. Relating to media and foreign affairs and the role of the media in political life, Dr. Mike Fitzgerald and two of his students provide us with āA Comparative Study of Images Created by Press Coverage of the United States and the Republic of Belarus.ā
Relating to health policy, Dr. David Mirvis, recently appointed as a Senior Fellow for Health Policy at the Center, explores the public policy implications of viewing health as an engine of economic growth.
Relating to energy and environmental policy, Drs. Bruce Tonn and Amy Gibson and Baker Scholars Stephanie Smith and Rachel Tuck explore U.S. Attitudes and Perspectives on National Energy Policy. I am also very pleased that this issue includes a report of an excellent conference ā āFormulation of a Bipartisan Energy and Climate Policy: Toward and Open and Transparent Process ā- that was co-sponsored by the Baker Center and the Woodrow Wilson International Center for Scholars. This issue also includes the result ofanother successful collaboration between the Baker and Wilson Centers that focused on āFive Public Policy Ideas for Building Obamaās New Economy.ā I look forward to further productive collaborations between the Baker and Wilson Centers.
Relating to global security policy, this issue includes a Student Symposium onNational Security. Although the Baker Center Journal has provided an outlet for publication of student scholarship since its inception, I am particularly pleased that the student co-editors - Baker Scholars Elizabeth Wilson Vaughan and Bradford A. Vaughan - took the initiative to expand upon the efforts of their predecessors and to provide us with an expanded set of excellent students essays each of which addresses an important national security policy issue. It is an important part of the Baker Centerās mission to engage UTK students in the political and public policy process, and I applaud our student authors fortheir contributions to this symposium.
I hope you find this issue of the Baker Center Journal for Applied Public Policy to be both interesting and thought-provoking and that it will encourage you to participate in Americaās unique and wonderful political and policy processes
Relationships of Polychlorinated Biphenyls and Dichlorodiphenyldichloroethylene (p,pā-DDE) with Testosterone Levels in Adolescent Males
Background: Concern persists over endocrine-disrupting effects of persistent organic pollutants (POPs) on human growth and sexual maturation. Potential effects of toxicant exposures on testosterone levels during puberty are not well characterized.
Objectives: In this study we evaluated the relationship between toxicants [polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,pĀ“-DDE), hexachlorobenzene (HCB), and lead] and testosterone levels among 127 Akwesasne Mohawk males 10 to \u3c 17 years of age with documented toxicant exposures.
Methods: Data were collected between February 1996 and January 2000. Fasting blood specimens were collected before breakfast by trained Akwesasne Mohawk staff. Multivariable regression models were used to estimates associations between toxicants and serum testosterone, adjusted for other toxicants, Tanner stage, and potential confounders.
Results: The sum of 16 PCB congeners (Ī£16PCBs) that were detected in ā„ 50% of the population was significantly and negatively associated with serum testosterone levels, such that a 10% change in exposure was associated with a 5.6% decrease in testosterone (95% CI: ā10.8, ā0.5%). Of the 16 congeners, the more persistent ones (Ī£8PerPCBs) were related to testosterone, whereas the less persistent ones, possibly reflecting more recent exposure, were not. When PCB congeners were subgrouped, the association was significant for the sum of eight more persistent PCBs (5.7% decrease; 95% CI: ā11, ā0.4%), and stronger than the sum of six less persistent congeners (3.1% decrease; 95% CI: ā7.2, 0.9%). p,pĀ“-DDE was positively but not significantly associated with serum testosterone (5.2% increase with a 10% increase in exposure; 95% CI: ā0.5, 10.9%). Neither lead nor HCB was significantly associated with testosterone levels.
Conclusions: Exposure to PCBs, particularly the more highly persistent congeners, may negatively influence testosterone levels among adolescent males. The positive relationship between p,pĀ“-DDE and testosterone indicates that not all POPs act similarly
Mapping workforce configuration and operational models in Australian emergency departments: a national survey
Objective Hospital emergency departments (ED) in Australia and internationally have been experiencing increased demand, resulting in reduced hospital quality, impaired access and adverse health outcomes. Effective evaluation of new ED service models and their effect on outcomes is reliant on baseline measures of the staffing configuration and organisational characteristics of the EDs being studied. The aim of the present study was to comprehensively measure these variables in Australian EDs. Methods Australian hospital EDs with 24-h medical and nursing cover were identified and invited to participate in the study. Telephone interviews were conducted with nursing or medical department managers to collect data related to hospital characteristics, ED workforce and training and ED service and operational models. Results Surveys were completed in 87% of the population sample (nā=ā135). Metropolitan EDs were significantly more likely to retain higher full-time equivalents (FTEs) in several medical (staff specialist, registrar, resident and intern) and nursing (nurse practitioner (NP), nurse educator, nurse unit manager and registered nurse) positions. NPs were employed by 52% of Australian EDs overall, but this ranged from 40% to 75% depending on jurisdiction. The most commonly used operational models were FastTrack teams (72% of EDs), short-stay/observational unit (59%) and patient liaison models for aged care (84%) and mental health (61%). EDs that employed NPs were significantly more likely to use FastTrack (Pā=ā0.002). Allied health services most frequently available within these EDs were radiology (60%), social work (69%), physiotherapy (70%) and pharmacy (65%). Conclusions The present study has established a baseline measure of the staffing configuration and organisational characteristics of Australian EDs. What is known about the topic? EDs are overcrowded due, in part, to the combined effect of increased service demand and access block. Innovative service and workforce models have been implemented by health departments aiming to improve service and performance. National uptake of these service and workforce innovations is unknown. What does this paper add? The present study is the most comprehensive to date profiling Australian EDs covering hospital characteristics, workforce configuration, operational models and NP service patterns and practice. What are the implications for practitioners? Information from the present study will assist health service planners to evaluate workforce and service reform models, and to monitor trends in emergency service development. </jats:p
Effect of Alpine glaciation on thermochronometer ageāelevation profiles
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94703/1/grl22545.pd
Financing a sustainable ocean economy
The ocean, which regulates climate and supports vital ecosystem services, is crucial to our Earth system and livelihoods. Yet, it is threatened by anthropogenic pressures and climate change. A healthy ocean that supports a sustainable ocean economy requires adequate financing vehicles that generate, invest, align, and account for financial capital to achieve sustained ocean health and governance. However, the current finance gap is large; we identify key barriers to financing a sustainable ocean economy and suggest how to mitigate them, to incentivize the kind of public and private investments needed for topnotch science and management in support of a sustainable ocean economy
Elevated atmospheric [CO2] can dramatically increase wheat yields in semi-arid environments and buffer against heat waves
Wheat production will be impacted by increasing concentration of atmospheric CO2 [CO2], which is expected to rise from about 400 Ī¼mol molā1 in 2015 to 550 Ī¼mol molā1 by 2050. Changes to plant physiology and crop responses from elevated [CO2] (e[CO2]) are well documented for some environments, but field-level responses in dryland Mediterranean environments with terminal drought and heat waves are scarce. The Australian Grains Free Air CO2 Enrichment facility was established to compare wheat (Triticum aestivum) growth and yield under ambient (~370 Ī¼molā1 in 2007) and e[CO2] (550 Ī¼molā1) in semi-arid environments. Experiments were undertaken at two dryland sites (Horsham and Walpeup) across three years with two cultivars, two sowing times and two irrigation treatments. Mean yield stimulation due to e[CO2] was 24% at Horsham and 53% at Walpeup, with some treatment responses greater than 70%, depending on environment. Under supplemental irrigation, e[CO2] stimulated yields at Horsham by 37% compared to 13% under rainfed conditions, showing that water limited growth and yield response to e[CO2]. Heat wave effects were ameliorated under e[CO2] as shown by reductions of 31% and 54% in screenings and 10% and 12% larger kernels (Horsham and Walpeup). Greatest yield stimulations occurred in the e[CO2] late sowing and heat stressed treatments, when supplied with more water. There were no clear differences in cultivar response due to e[CO2]. Multiple regression showed that yield response to e[CO2] depended on temperatures and water availability before and after anthesis. Thus, timing of temperature and water and the crop's ability to translocate carbohydrates to the grain postanthesis were all important in determining the e[CO2] response. The large responses to e[CO2] under dryland conditions have not been previously reported and underscore the need for field level research to provide mechanistic understanding for adapting crops to a changing climate
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