1,569 research outputs found

    The Catholic Position on Abortion

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    STEMteach: Preparing the Next Generation of Mathematics and Science Teachers

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    With an increasing demand for individuals prepared in Science, Technology, Engineering, and Mathematics (STEM), one university responded to this call by changing its teacher preparation program. Better-prepared mathematics and science teachers have the opportunity to engage and excite students, thereby preparing and promoting more of them to enter the STEM professions. The described program is a replication of the national UTeach model that recruits content majors in mathematics and science to explore the teaching profession during a first-semester course that includes an early field experience in the elementary grades. This field experience is designed to be engaging for both the teacher education candidates and the elementary students in an effort to demonstrate the joy of teaching and to retain the candidates in the program. The ultimate goal of the program is to increase the production of quality secondary mathematics and science teachers who can transfer their own deep understanding of their content to students so that these students will be career and college ready in the STEM disciplines

    Technical summary of accomplishments made in preparation for the USSR barley exploratory experiment

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    The highlights of the work accomplished under each subcomponent of the U.S.S.R. Barley Pilot Experiment, which is scheduled for completion in 1984, are summarized. A significant amount of developmental system implementation activity was in the final stages of preparation prior to the rescoping of project tasks. Unpublished materials which are significant to this exploratory experiment are incorporated into the appendixes

    Search for transient ultralight dark matter signatures with networks of precision measurement devices using a Bayesian statistics method

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    We analyze the prospects of employing a distributed global network of precision measurement devices as a dark matter and exotic physics observatory. In particular, we consider the atomic clocks of the Global Positioning System (GPS), consisting of a constellation of 32 medium-Earth orbit satellites equipped with either Cs or Rb microwave clocks and a number of Earth-based receiver stations, some of which employ highly-stable H-maser atomic clocks. High-accuracy timing data is available for almost two decades. By analyzing the satellite and terrestrial atomic clock data, it is possible to search for transient signatures of exotic physics, such as "clumpy" dark matter and dark energy, effectively transforming the GPS constellation into a 50,000km aperture sensor array. Here we characterize the noise of the GPS satellite atomic clocks, describe the search method based on Bayesian statistics, and test the method using simulated clock data. We present the projected discovery reach using our method, and demonstrate that it can surpass the existing constrains by several order of magnitude for certain models. Our method is not limited in scope to GPS or atomic clock networks, and can also be applied to other networks of precision measurement devices.Comment: See also Supplementary Information located in ancillary file

    Using Tax Refunds to Promote Asset Building in Low-Income Households: Program and Policy Options

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    Using Tax Refunds to Promote Asset Building in Low-Income Households: Program and Policy Option

    Guideline update for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 1: Introduction and methodology

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    pre-printFusion procedures are an accepted and successful management strategy to alleviate pain and/or neurological symptoms associated with degenerative disease of the lumbar spine. In 2005, the first version of the "Guidelines for the performance of fusion procedures for degenerative disease of the lumbar spine" was published in the Journal of Neurosurgery: Spine. In an effort to incorporate evidence obtained since the original publication of these guidelines, an expert panel of neurosurgical and orthopedic spine specialists was convened in 2009. Topics reviewed were essentially identical to the original publication. Selected manuscripts from the first iteration of these guidelines as well as relevant publications between 2005 through 2011 were reviewed. Several modifications to the methodology of guideline development were adopted for the current update. In contrast to the 2005 guidelines, a 5-tiered level of evidence strategy was employed, primarily allowing a distinction between lower levels of evidence. The qualitative descriptors (standards/guidelines/options) used in the 2005 recommendations were abandoned and replaced with grades to reflect the strength of medical evidence supporting the recommendation. Recommendations that conflicted with the original publication, if present, were highlighted at the beginning of each chapter. As with the original guideline publication, the intent of this update is to provide a foundation from which an appropriate treatment strategy can be formulated

    Guideline update for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 16: Bone graft extenders and substitutes as an adjunct for lumbar fusion

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    pre-printIn an attempt to enhance the potential to achieve a solid arthrodesis and avoid the morbidity of harvesting autologous iliac crest bone (AICB) for a lumbar fusion, numerous alternatives have been investigated. The use of these fusion adjuncts has become routine despite a lack of convincing evidence demonstrating a benefit to justify added costs or potential harm. Potential alternatives to AICB include locally harvested autograft, calcium-phosphate salts, demineralized bone matrix (DBM), and the family of bone morphogenetic proteins (BMPs). In particular, no option has created greater controversy than the BMPs. A significant increase in the number of publications, particularly with respect to the BMPs, has taken place since the release of the original guidelines. Both DBM and the calciumphosphate salts have demonstrated efficacy as a graft extender or as a substitute for AICB when combined with local autograft. The use of recombinant human BMP-2 (rhBMP-2) as a substitute for AICB, when performing an interbody lumbar fusion, is considered an option since similar outcomes have been observed; however, the potential for heterotopic bone formation is a concern. The use of rhBMP-2, when combined with calcium phosphates, as a substitute for AICB, or as an extender, when used with local autograft or AICB, is also considered an option as similar fusion rates and clinical outcomes have been observed. Surgeons electing to use BMPs should be aware of a growing body of literature demonstrating unique complications associated with the use of BMPs

    Guideline update for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 17: Bone growth stimulators as an adjunct for lumbar fusion

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    pre-printThe relationship between the formation of a solid arthrodesis and electrical and electromagnetic energy is well established; most of the information on the topic, however, pertains to the healing of long bone fractures. The use of both invasive and noninvasive means to supply this energy and supplement spinal fusions has been investigated. Three forms of electrical stimulation are routinely used: direct current stimulation (DCS), pulsed electromagnetic field stimulation (PEMFS), and capacitive coupled electrical stimulation (CCES). Only DCS requires the placement of electrodes within the fusion substrate and is inserted at the time of surgery. Since publication of the original guidelines, few studies have investigated the use of bone growth stimulators. Based on the current review, no conflict with the previous recommendations was generated. The use of DCS is recommended as an option for patients younger than 60 years of age, since a positive effect on fusion has been observed. The same, however, cannot be stated for patients over 60, because DCS did not appear to have an impact on fusion rates in this population. No study was reviewed that investigated the use of CCES or the routine use of PEMFS. A single low-level study demonstrated a positive impact of PEMFS on patients undergoing revision surgery for pseudarthrosis, but this single study is insufficient to recommend for or against the use of PEMFS in this patient population

    Is it possible to increase the sustainability of arable and ruminant agriculture by reducing inputs?

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    Until recently, agricultural production was optimised almost exclusively for profit but now farming is under pressure to meet environmental targets. A method is presented and applied for optimising the sustainability of agricultural production systems in terms of both economics and the environment. Components of the agricultural production chain are analysed using environmental life-cycle assessment (LCA) and a financial value attributed to the resources consumed and burden imposed on the environment by agriculture, as well as to the products. The sum of the outputs is weighed against the inputs and the system considered sustainable if the value of the outputs exceeds those of the inputs. If this ratio is plotted against the sum of inputs for all levels of input, a diminishing returns curve should result and the optimum level of sustainability is located at the maximum of the curve. Data were taken from standard economic almanacs and from published LCA reports on the extent of consumption and environmental burdens resulting from farming in the UK. Land-use is valued using the concept of ecosystem services. Our analysis suggests that agricultural systems are sustainable at rates of production close to current levels practiced in the UK. Extensification of farming, which is thought to favour non-food ecosystem services, requires more land to produce the same amount of food. The loss of ecosystem services hitherto provided by natural land brought into production is greater than that which can be provided by land now under extensive farming. This loss of ecosystem service is large in comparison to the benefit of a reduction in emission of nutrients and pesticides. However, food production is essential, so the coupling of subsidies that represent a relatively large component of the economic output in EU farming, with measures to reduce pollution are well-aimed. Measures to ensure that as little extra land is brought into production as possible or that marginal land is allowed to revert to nature would seem to be equally well-aimed, even if this required more intensive use of productive areas. We conclude that current arable farming in the EU is sustainable with either realistic prices for products or some degree of subsidy and that productivity per unit area of land and greenhouse gas emission (subsuming primary energy consumption) are the most important pressures on the sustainability of farming

    The Value of Green Residential Homes

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