An experiment in the teaching of plane geometry comparing the formal method with the informal method

Thesis (Ed.M.)--Boston University This item was digitized by the Internet Archive

Isolation and Expression of a Gene Cluster Responsible for Biosynthesis of the Glycopeptidolipid Antigens of \u3cem\u3eMicobacterium avium\u3c/em\u3e

Bacteria within the Mycobacterium avium complex are prominent in the environment and are a source of serious disseminated infections in patients with AIDS. Serovars of the M. avium complex are distinguished from all other mycobacteria and from one another by the presence of highly antigenic glycolipids, the glycopeptidolipids, on their surfaces. A genomic library of DNA from serovar 2 of the M. avium complex was constructed in the Escherichia coli-Mycobacterium shuttle cosmid, pYUB18, and used to clone and express in Mycobacterium smegmatis the genes responsible for the biosynthesis of the oligosaccharide segment of the M. avium serovar 2-specific glycopeptidolipid. The responsible gene cluster was mapped to a 22- to 27-kb functional region of the M. avium genome. The recombinant glycolipid was also isolated by high-pressure liquid chromatography and chemically characterized, by gas chromatography-mass spectrometry and fast atom bombardment-mass spectrometry, to demonstrate that the lipopeptide core originated in M. smegmatis, whereas the oligosaccharide segment arose from the cloned M. avium genes. This first-time demonstration of the cloning and expression, in a nonpathogenic mycobacterium, of the genes encoding complex cell wall glycoconjugates from a pathogenic mycobacterium presents a new approach for studying the role of such products in disease processes

Historical and modern disturbance regimes of pinon-juniper vegetation in the Western U.S.

Pinon-juniper vegetation covers some 100 million acres in the western U.S. where it provides economic products, ecosystem services, biodiversity, and aesthetic beauty in some of the most scenic landscapes of North America. There are concerns, however, that the ecological dynamics of pinon-juniper woodlands have changed since Euro-American settlement, that trees are growing unnaturally dense, and that woodlands are encroaching into former grasslands and shrublands. Yet surprisingly little research has been conducted on historical conditions and ecological processes in pinon-juniper vegetation, and the research that does exist demonstrates that pinon-juniper structure, composition, and disturbance regimes were very diverse historically as well as today. The purpose of this report is to briefly summarize our current understanding of historical stand structures, disturbance regimes, and landscape dynamics in pinon-juniper vegetation throughout the western U.S. The authors gathered for a workshop in Boulder, CO, on August 22-24, 2006, to develop the information presented here

Deep Underground Science and Engineering Laboratory - Preliminary Design Report

The DUSEL Project has produced the Preliminary Design of the Deep Underground Science and Engineering Laboratory (DUSEL) at the rehabilitated former Homestake mine in South Dakota. The Facility design calls for, on the surface, two new buildings - one a visitor and education center, the other an experiment assembly hall - and multiple repurposed existing buildings. To support underground research activities, the design includes two laboratory modules and additional spaces at a level 4,850 feet underground for physics, biology, engineering, and Earth science experiments. On the same level, the design includes a Department of Energy-shepherded Large Cavity supporting the Long Baseline Neutrino Experiment. At the 7,400-feet level, the design incorporates one laboratory module and additional spaces for physics and Earth science efforts. With input from some 25 science and engineering collaborations, the Project has designed critical experimental space and infrastructure needs, including space for a suite of multidisciplinary experiments in a laboratory whose projected life span is at least 30 years. From these experiments, a critical suite of experiments is outlined, whose construction will be funded along with the facility. The Facility design permits expansion and evolution, as may be driven by future science requirements, and enables participation by other agencies. The design leverages South Dakota's substantial investment in facility infrastructure, risk retirement, and operation of its Sanford Laboratory at Homestake. The Project is planning education and outreach programs, and has initiated efforts to establish regional partnerships with underserved populations - regional American Indian and rural populations

Kyphoplasty vs Vertebroplasty: A Systematic Review of Height Restoration in Osteoporotic Vertebral Compression Fractures

Background: Back pain is a leading cause of morbidity in older US adults, especially those with osteoporosis. Osteoporotic vertebral compression fractures (OVCF) commonly occur in people with osteoporosis. ~1/3 of OVCF are symptomatic with acute or chronic low back pain. Annual US cases of osteoporosis with OVCF are ~700,000/year. OVCF and osteoporosis cause high levels of morbidity, decreased functional independence, and chronic pain. Conservative treatment for OVCF is often insufficient for many patients. Insufficient vertebral height caused by OVCF can lead to spinal deformities, reduced pulmonary function, depression, reduced mobility, and lower quality of life. Surgical correction is a viable option for increasing vertebral height in patients with OVCF. Kyphoplasty and vertebroplasty are vertebral augmentation therapies that can restore bone height for the alleviation of OVCF. Both procedures involve injection of a polymer cement into sites of fracture. Only kyphoplasty involves using an inflatable balloon to first make space for polymer injection. These minimally invasive procedures are recommended for patients who have OVCF but are refractory to conventional therapies. Also, patients with benign bone tumors or traumatic acute vertebral compression fractures with a local kyphotic angle greater than 15 degrees can benefit from these procedures. The aim of our systematic review was to identify the overall effectiveness of kyphoplasty and vertebroplasty. Height restoration after treatment was used as the key indicator of therapeutic success. Restoration of function and pain relief were also assessed. Purpose: To critically investigate whether vertebral body height restoration correlates with pain relief after kyphoplasty and vertebroplasty. Primary Outcome: height restoration. Secondary Outcomes: pain relief, functionality, cement leakage, Cobb’s Angle, wedge angle restoration, kyphosis angle restoration, and Gardner’s angle. We assessed only randomized controlled trials (RCTs) to generate a more robust and clinically applicable. We also provide an update on the literature comparing kyphoplasty versus vertebroplasty for height restoration, pain relief, and function restoration. We searched 6 databases to ensure that the review was comprehensive. Methods: We performed a systematic review per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol. Level II randomized controlled trials assessing kyphoplasty and/or vertebroplasty were included. Study selection inclusion criteria: patients \u3e 18 years, in English, study of OVCF, active comparator vs placebo, outcome measure of height restoration, with pain relief and functionality as secondary outcomes. Of 4147 individual articles, 238 articles were screened, and 33 were analyzed. Of the 33 analyzed studies, 6 compared kyphoplasty to vertebroplasty. Results: Vertebral Height Restoration 7 studies of vertobroplasty 2 showed height loss 1 showed height restoration 2 showed absolute height gain 20 studies of kyphoplasty None showed height loss 8 showed height restoration 8 showed absolute height gain 6 head-to-head comparisons 3 showed correlation of cement injection volume with improved height 5 favored kyphoplasty for height restoration Alleviation of Pain: Assessed by visual analogue scale (VAS)score 6 of 6 vertebroplasty studies showed reduced postop pain 6 of 18 kyphoplasty studies showed sustained reduced pain at 12 months 6 studies compared kyphoplasty & vertebroplasty and none saw a difference between the 2 for reducing postop pain Restoration of Function Assessed by Oswestry disability index (ODI) 3 studies showed improved ODI after vertebroplasty at 18 to 36 months postop 4 studies showed improved ODI at 12 months after kyphoplasty 3 studies compared kyphoplasty & vertebroplasty and all showed lower postop ODI Conclusions: Both kyphoplasty and vertebroplasty are effective treatments for OVCF and are viable options for OVCF patients. Both treatments restored some vertebral body height, reduced kyphosis angle, improved Cobbs angle, and improved wedge angle. Both treatments showed similar benefits of pain reduction and improved functionality. It was unclear whether fracture type or age of fracture influence procedure outcomes. Kyphoplasty has the possibility of cement leakage, which can lead to negative outcomes. It was not possible to conclude whether one approach was superior.https://scholarlycommons.henryford.com/sarcd2021/1006/thumbnail.jp

Policy Feedback and the Politics of the Affordable Care Act

There is a large body of literature devoted to how “policies create politics” and how feedback effects from existing policy legacies shape potential reforms in a particular area. Although much of this literature focuses on self‐reinforcing feedback effects that increase support for existing policies over time, Kent Weaver and his colleagues have recently drawn our attention to self‐undermining effects that can gradually weaken support for such policies. The following contribution explores both self‐reinforcing and self‐undermining policy feedback in relationship to the Affordable Care Act, the most important health‐care reform enacted in the United States since the mid‐1960s. More specifically, the paper draws on the concept of policy feedback to reflect on the political fate of the ACA since its adoption in 2010. We argue that, due in part to its sheer complexity and fragmentation, the ACA generates both self‐reinforcing and self‐undermining feedback effects that, depending of the aspect of the legislation at hand, can either facilitate or impede conservative retrenchment and restructuring. Simultaneously, through a discussion of partisan effects that shape Republican behavior in Congress, we acknowledge the limits of policy feedback in the explanation of policy stability and change

Treatment effect of switching from intravenous to subcutaneous C1-inhibitor for prevention of hereditary angioedema attacks: COMPACT subgroup findings

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Control-focused, nonlinear and time-varying modelling of dielectric elastomer actuators with frequency response analysis

Current models of dielectric elastomer actuators (DEAs) are mostly constrained to first principal descriptions that are not well suited to the application of control design due to their computational complexity. In this work we describe an integrated framework for the identification of control focused, data driven and time-varying DEA models that allow advanced analysis of nonlinear system dynamics in the frequency-domain. Experimentally generated input–output data (voltage-displacement) was used to identify control-focused, nonlinear and time-varying dynamic models of a set of film-type DEAs. The model description used was the nonlinear autoregressive with exogenous input structure. Frequency response analysis of the DEA dynamics was performed using generalized frequency response functions, providing insight and a comparison into the time-varying dynamics across a set of DEA actuators. The results demonstrated that models identified within the presented framework provide a compact and accurate description of the system dynamics. The frequency response analysis revealed variation in the time-varying dynamic behaviour of DEAs fabricated to the same specifications. These results suggest that the modelling and analysis framework presented here is a potentially useful tool for future work in guiding DEA actuator design and fabrication for application domains such as soft robotics