Intermittent Dissipation and Heating in 3D Kinetic Plasma Turbulence

High resolution, fully kinetic, three dimensional (3D) simulation of collisionless plasma turbulence shows the development of turbulence characterized by sheetlike current density structures spanning a range of scales. The nonlinear evolution is initialized with a long wavelength isotropic spectrum of fluctuations having polarizations transverse to an imposed mean magnetic field. We present evidence that these current sheet structures are sites for heating and dissipation, and that stronger currents signify higher dissipation rates. The analyses focus on quantities such as J·E, electron, and proton temperatures, and conditional averages of these quantities based on local electric current density. Evidently, kinetic scale plasma, like magnetohydrodynamics, becomes intermittent due to current sheet formation, leading to the expectation that heating and dissipation in astrophysical and space plasmas may be highly nonuniform. Comparison with previous results from 2D kinetic simulations, as well as high frequency solar wind observational data, are discussed.

Intermittent dissipation at kinetic scales in collisionless plasma turbulence

High resolution kinetic simulations of collisionless plasma driven by shear show the development of turbulence characterized by dynamic coherent sheetlike current density structures spanning a range of scales down to electron scales. We present evidence that these structures are sites for heating and dissipation, and that stronger current structures signify higher dissipation rates. Evidently, kinetic scale plasma, like magnetohydrodynamics, becomes intermittent due to current sheet formation, leading to the expectation that heating and dissipation in astrophysical and space plasmas may be highly nonuniform and patchy.

Converting Paper Medical Records to Electronic Version To Support Breast Cancer Translational Research and Clinical Practice

Background: The healthcare system has extremely large volumes of patients' paper medical records (PMRs) scattered throughout various medical facilities. Currently the industry is transitioning to Electronic Medical Records (EMR). Although each source of information is equally important, a complete longitudinal health record is rarely available or currently attainable. The goal of this effort is to convert the existing PMRs into searchable electronic equivalents and merge them with existing EMRs to create a more complete longitudinal health record to support clinical care and biomedical research.Method: Using a subset of PMRs for subjects enrolled in the Clinical Breast Care Project at Walter Reed Army Medical Center, (WRAMC), we are developing an automated method to digitize and index the records, extract the biomedical information and prepare the data for delivery to clinicians and researchers. The electronic records were loaded into a database for immediate access by clinicians. To support translational research, MRs need to be de-identified, and information extracted and loaded into a research database; we used ten MRs to develop the operational method. Several methods were tested in the de-identification process: 1) manually, by striking out the protected health information (PHI) on paper before it was digitized and 2) “electronically”, by redacting the record electronically on the computer after it was digitized. We are in the process of testing automated data extraction tools and natural language processors to automatically de-identify and extract data from the EMR.Result: We quickly realized that only 10% of PMRs existed onsite at WRAMC; remaining MRs were held by the patients or other medical facilities. Approximately 300 PMRs, containing 66,600 pages, were scanned and digitized for this project. We have created a successful digitization process, which includes creating PDFs with hidden and searchable information. We have compared the effort and accuracy of various redaction methods. To de-identify 10 records, it took ∼10 hours manually and ∼20 hours electronically. It took longer electronically because of the preparations to ensure the removed information could not be retrieved. We expect that automated redaction tools will greatly reduce that effort. We also found that the electronic method had a 99% accuracy compared to 96% for the paper method. A portal prototype to allow access to medical records by clinicians and researchers is currently being tested and evaluated.Discussion: Conversion of non-searchable data into an explorable and computable format will enable clinicians to acquire needed information more conveniently in their clinical care including treatment plan development. Similarly, properly de-identified, complete MRs will serve as a rich source of clinical information to support translational research. Although the method we are developing will initially satisfy the CBCP need for clinical service and research, it will be further developed into a full solution to expand into other disease condition fields.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5123.

Gastrointestinal involvement in Henoch-Schönlein purpura

We report a 20-year-old young man with Henoch-Schönlein purpura (HSP) who presented with abdominal pain, arthralgia, and skin rash. The gastrointestinal tract was viewed by upper endoscopy and colonoscopy. We found characteristic endoscopic findings in the stomach, cecum and sigmoid colon, the combination of which has rarely been demonstrated in one patient. Histologic examination of skin biopsy specimens and gastrointestinal tract revealed leukocytoclastic vasculitis with positive staining for IgA in the capillaries. The clinical course of this patient was further improved after the combined therapy with steroids and immunosuppressive drug.

Blastocystis hominis as a cause of hypoalbuminemia and anasarca

The protozoan Blastocystis hominis has been considered nonpathogenic, but this classification has come under scrutiny in light of reports in the medical literature indicating it could be the cause of intestinal disorders and, in one case, hypoalbuminemia. Reported here is a severe case of infection with B. hominis that caused acute gastroenteritis with prolonged diarrhea, hypoalbuminemia and anasarca. The diagnosis was based on the parasitological finding, since no other pathological evidence was found. The patient responded favorably to treatment with metronidazole for 10 days. This case supports the idea that B. hominis should be considered as a cause of opportunistic infection in debilitated patients despite the controversy surrounding its pathogenicity.

Skin lesions as the presenting symptom of a gastrointestinal disease

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Dermatomyositis as presenting symptom of Hodgkin's disease

The association between dermatomyositis and malignancy is well documented. However, the association between dermatomyositis and Hodgkin's disease is very unusual, particularly in children, adolescents, and young adults. A MEDLINE search of the literature revealed only 13 previous cases.