A method for obtaining Darboux transformations

In this paper we give a method to obtain Darboux transformations (DTs) of integrable equations. As an example we give a DT of the dispersive water wave equation. Using the Miura map, we also obtain the DT of the Jaulent-Miodek equation. \end{abstract

Faster linearizability checking via PP-compositionality

Linearizability is a well-established consistency and correctness criterion for concurrent data types. An important feature of linearizability is Herlihy and Wing's locality principle, which says that a concurrent system is linearizable if and only if all of its constituent parts (so-called objects) are linearizable. This paper presents $P$-compositionality, which generalizes the idea behind the locality principle to operations on the same concurrent data type. We implement $P$-compositionality in a novel linearizability checker. Our experiments with over nine implementations of concurrent sets, including Intel's TBB library, show that our linearizability checker is one order of magnitude faster and/or more space efficient than the state-of-the-art algorithm.Comment: 15 pages, 2 figure

Adolescent Resilience: Promotive Factors That Inform Prevention

Resilience theory provides a framework for studying and understanding how some youths overcome risk exposure and guides the development of interventions for prevention using a strengths‐based approach. In this article, we describe basic concepts of the theory, such as promotive factors, and distinguish assets and resources that help youths overcome the negative effects of risk exposure. We also present three models of resilience theory—compensatory, protective, and challenge—and review empirical research on three promotive factors—ethnic identity, social support, and prosocial involvement—that include individual, family, and community levels of analysis and have modifiable qualities for informing interventions. Finally, we present examples of how research findings from the three promotive factors can be translated into interventions to enhance youth development.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/101789/1/cdep12042.pd

Conservation laws of semidiscrete canonical Hamiltonian equations

There are many evolution partial differential equations which can be cast into Hamiltonian form. Conservation laws of these equations are related to one-parameter Hamiltonian symmetries admitted by the PDEs. The same result holds for semidiscrete Hamiltonian equations. In this paper we consider semidiscrete canonical Hamiltonian equations. Using symmetries, we find conservation laws for the semidiscretized nonlinear wave equation and Schrodinger equation.Comment: 19 pages, 2 table

Approximation of excitonic absorption in disordered systems using a compositional component weighted CPA

Employing a recently developed technique of component weighted two particle Green's functions in the CPA of a binary substitutional alloy $A_cB_{1-c}$ we extend the existing theory of excitons in such media using a contact potential model for the interaction between electrons and holes to an approximation which interpolates correctly between the limits of weak and strong disorder. With our approach we are also able to treat the case where the contact interaction between carriers varies between sites of different types, thus introducing further disorder into the system. Based on this approach we study numerically how the formation of exciton bound states changes as the strengths of the contact potentials associated with either of the two site types are varied through a large range of parameter values.Comment: 27 pages RevTeX (preprint format), 13 Postscript figure file

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

Impact of COVID-19 Pandemic on Patients\u27 Perceptions of Safety and Need for Elective Foot and Ankle Surgery in the United States

Background: With the development of the COVID-19 pandemic, elective foot and ankle surgeries were delayed throughout the United States to divert health care resources and limit exposure. Little is known about the impact of COVID-19 on patient\u27s willingness to proceed with elective procedures once restrictions are lifted and factors contributing to such decision. Methods: Patients across 6 US orthopedic institutions who had their elective foot and ankle surgeries cancelled secondary to the pandemic were given a questionnaire. Specifically, patients were asked about their willingness to move forward with surgery once restrictions were lifted and if not why. Pain-level and pain medication use were also assessed. Univariate analysis was used to identify factors that contribute to patient\u27s decisions. Results: A total of 150 patients participated in this study. Twenty-one (14%) opted not to proceed with surgery once restrictions were lifted. Forty-three percent (n = 9) listed concern for COVID infection as the reason; however, 14% of them would proceed if procedures were performed in surgery center. Twenty-nine (19% of the total cohort) patients had increased pain and 11% of patients were taking more pain meds because of the delay to their procedure. Patients who decided not to proceed with surgery reported pain reduction (3% vs 14%) and lower increase in pain medication used (5% vs 12%). Conclusion: COVID-19 has made a significant impact on the health care system. Delay of elective foot and ankle procedures impact patient quality of life and outcomes. Access to surgery centers may provide a partial solution during the pandemic. Level of Evidence: Level III

Altering Murine Leukemia Virus Integration Through Disruption of the Integrase and BET Protein Family Interaction

We report alterations to the murine leukemia virus (MLV) integrase (IN) protein that successfully result in decreasing its integration frequency at transcription start sites and CpG islands, thereby reducing the potential for insertional activation. The host bromo and extraterminal (BET) proteins Brd2, 3 and 4 interact with the MLV IN protein primarily through the BET protein ET domain. Using solution NMR, protein interaction studies, and next generation sequencing, we showthat the C-terminal tail peptide region ofMLV IN is important for the interaction with BET proteins and that disruption of this interaction through truncation mutations affects the global targeting profile of MLV vectors. The use of the unstructured tails of gammaretroviral INs to direct association with complexes at active promoters parallels that used by histones and RNA polymerase II. Viruses bearingMLV IN C-terminal truncations can provide new avenues to improve the safety profile of gammaretroviral vectors for human gene therapy

How are "teaching the teachers" courses in evidence based medicine evaluated? A systematic review

Background Teaching of evidence-based medicine (EBM) has become widespread in medical education. Teaching the teachers (TTT) courses address the increased teaching demand and the need to improve effectiveness of EBM teaching. We conducted a systematic review of assessment tools for EBM TTT courses. To summarise and appraise existing assessment methods for teaching the teachers courses in EBM by a systematic review. Methods We searched PubMed, BioMed, EmBase, Cochrane and Eric databases without language restrictions and included articles that assessed its participants. Study selection and data extraction were conducted independently by two reviewers. Results Of 1230 potentially relevant studies, five papers met the selection criteria. There were no specific assessment tools for evaluating effectiveness of EBM TTT courses. Some of the material available might be useful in initiating the development of such an assessment tool. Conclusion There is a need for the development of educationally sound assessment tools for teaching the teachers courses in EBM, without which it would be impossible to ascertain if such courses have the desired effect

A web-based library consult service for evidence-based medicine: Technical development

BACKGROUND: Incorporating evidence based medicine (EBM) into clinical practice requires clinicians to learn to efficiently gain access to clinical evidence and effectively appraise its validity. Even using current electronic systems, selecting literature-based data to solve a single patient-related problem can require more time than practicing physicians or residents can spare. Clinical librarians, as informationists, are uniquely suited to assist physicians in this endeavor. RESULTS: To improve support for evidence-based practice, we have developed a web-based EBM library consult service application (LCS). Librarians use the LCS system to provide full text evidence-based literature with critical appraisal in response to a clinical question asked by a remote physician. LCS uses an entirely Free/Open Source Software platform and will be released under a Free Software license. In the first year of the LCS project, the software was successfully developed and a reference implementation put into active use. Two years of evaluation of the clinical, educational, and attitudinal impact on physician-users and librarian staff are underway, and expected to lead to refinement and wide dissemination of the system. CONCLUSION: A web-based EBM library consult model may provide a useful way for informationists to assist clinicians, and is feasible to implement