148 research outputs found

    Simulation of a NASA LEO Satellite Hybrid Network

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    Various issues associated with "Simulation of a NASA LEO Satellite Hybrid Network" are presented in viewgraph form. Specific topics include: 1) Objective of the investigation; 2) Satellite orbit description and included nodes; 3) TCP and FTP simulation descriptions; 4) Simulation results; and 5) Derived conclusions

    Familial Papillary Thyroid Carcinoma: A Retrospective Analysis

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    Background. Whether or not the familial form of papillary thyroid carcinoma is more aggressive than the sporadic form of the disease remains controversial. Methods. To explore this question and whether or not increased aggressiveness is more apparent in families with multiple affected members, we performed a chi square by trend analysis on our patients clinical and pathologic data comparing: first degree families with three or more affected members versus first degree families with two affected members versus sporadic cases of papillary thyroid carcinoma. Results. No statistically significant trends were seen for any presenting surgical pathology parameter, age at presentation, length of follow-up or gender distribution. The familial groups exhibited significant trends for higher rates of reoperation (P = 0.05) and/or requiring additional radioactive iodine therapy (P = 0.03), distant metastases (P = 0.003) and deaths (P = 0.01). These aggressive features were most apparent in certain families with three or more affected members. Conclusions. Using the chi square by trend analysis, a significant trend was seen for the familial form of papillary thyroid cancer to possess more aggressive features than the sporadic disease. Prompt recognition of the familial nature of the disease may provide earlier diagnosis and treatment in similarly affected family members

    Burkhardt-Cottingham sum rule and forward spin polarizabilities in Heavy Baryon Chiral Perturbation Theory

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    We study spin-dependent sum rules for forward virtual Compton scattering(VVCS) off the nucleon in heavy baryon chiral perturbation theory at order O(p4)O(p^4). We show how these sum rules can be evaluated from low energy expansions (in the virtual photon energy) of the forward VVCS amplitudes. We study in particular the Burkhardt -Cottingham sum rule in HBChPT and higher terms in the low energy expansion, which can be related to the generalized forward spin polarizabilities of the nucleon. The dependence of these observables on the photon virtuality Q2Q^2 can be accessed, at small and intermediate Q2Q^2 values, from existing and forthcoming data at Jefferson Lab.Comment: 16 pages,4 fig

    GRFS and CRFS in alternative donor hematopoietic cell transplantation for pediatric patients with acute leukemia.

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    We report graft-versus-host disease (GVHD)-free relapse-free survival (GRFS) (a composite end point of survival without grade III-IV acute GVHD [aGVHD], systemic therapy-requiring chronic GVHD [cGVHD], or relapse) and cGVHD-free relapse-free survival (CRFS) among pediatric patients with acute leukemia (n = 1613) who underwent transplantation with 1 antigen-mismatched (7/8) bone marrow (BM; n = 172) or umbilical cord blood (UCB; n = 1441). Multivariate analysis was performed using Cox proportional hazards models. To account for multiple testing, P \u3c .01 for the donor/graft variable was considered statistically significant. Clinical characteristics were similar between UCB and 7/8 BM recipients, because most had acute lymphoblastic leukemia (62%), 64% received total body irradiation-based conditioning, and 60% received anti-thymocyte globulin or alemtuzumab. Methotrexate-based GVHD prophylaxis was more common with 7/8 BM (79%) than with UCB (15%), in which mycophenolate mofetil was commonly used. The univariate estimates of GRFS and CRFS were 22% (95% confidence interval [CI], 16-29) and 27% (95% CI, 20-34), respectively, with 7/8 BM and 33% (95% CI, 31-36) and 38% (95% CI, 35-40), respectively, with UCB (P \u3c .001). In multivariate analysis, 7/8 BM vs UCB had similar GRFS (hazard ratio [HR], 1.12; 95% CI, 0.87-1.45; P = .39), CRFS (HR, 1.06; 95% CI, 0.82-1.38; P = .66), overall survival (HR, 1.07; 95% CI, 0.80-1.44; P = .66), and relapse (HR, 1.44; 95% CI, 1.03-2.02; P = .03). However, the 7/8 BM group had a significantly higher risk for grade III-IV aGVHD (HR, 1.70; 95% CI, 1.16-2.48; P = .006) compared with the UCB group. UCB and 7/8 BM groups had similar outcomes, as measured by GRFS and CRFS. However, given the higher risk for grade III-IV aGVHD, UCB might be preferred for patients lacking matched donors. © 2019 American Society of Hematology. All rights reserved

    Adrenomedullin is up-regulated in patients with pancreatic cancer and causes insulin resistance in β cells and mice

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    New-onset diabetes in patients with pancreatic cancer is likely to be a paraneoplastic phenomenon caused by tumor-secreted products. We aimed to identify the diabetogenic secretory product(s) of pancreatic cancer. Methods: Using microarray analysis, we identified adrenomedullin as a potential mediator of diabetes in patients with pancreatic cancer. Adrenomedullin was up-regulated in pancreatic cancer cell lines, in which supernatants reduced insulin signaling in beta cell lines. We performed quantitative reverse-transcriptase polymerase chain reaction and immunohistochemistry on human pancreatic cancer and healthy pancreatic tissues (controls) to determine expression of adrenomedullin messenger RNA and protein, respectively. We studied the effects of adrenomedullin on insulin secretion by beta cell lines and whole islets from mice and on glucose tolerance in pancreatic xenografts in mice. We measured plasma levels of adrenomedullin in patients with pancreatic cancer, patients with type 2 diabetes mellitus, and individuals with normal fasting glucose levels (controls). Results: Levels of adrenomedullin messenger RNA and protein were increased in human pancreatic cancer samples compared with controls. Adrenomedullin and conditioned media from pancreatic cell lines inhibited glucose-stimulated insulin secretion from beta cell lines and islets isolated from mice; the effects of conditioned media from pancreatic cancer cells were reduced by small hairpin RNA-mediated knockdown of adrenomedullin. Conversely, overexpression of adrenomedullin in mice with pancreatic cancer led to glucose intolerance. Mean plasma levels of adrenomedullin (femtomoles per liter) were higher in patients with pancreatic cancer compared with patients with diabetes or controls. Levels of adrenomedullin were higher in patients with pancreatic cancer who developed diabetes compared those who did not. Conclusions: Adrenomedullin is up-regulated in patients with pancreatic cancer and causes insulin resistance in β cells and mice.Fil: Aggarwal, Gaurav. Mayo Clinic College of Medicine; Estados UnidosFil: Ramachandran, Vijaya. University of Texas Health Science Center at Houston. University of Texas Md Anderson Cancer Center; Estados UnidosFil: Javeed, Naureen. Mayo Clinic College of Medicine; Estados UnidosFil: Arumugam, Thiruvengadam. University of Texas Health Science Center at Houston. University of Texas Md Anderson Cancer Center; Estados UnidosFil: Dutta, Shamit. Mayo Clinic College of Medicine; Estados UnidosFil: Klee, George G.. Mayo Clinic College of Medicine; Estados UnidosFil: Klee, Eric W.. Mayo Clinic College of Medicine; Estados UnidosFil: Smyrk, Thomas C.. Mayo Clinic College of Medicine; Estados UnidosFil: Bamlet, William. Mayo Clinic College of Medicine; Estados UnidosFil: Han, Jing Jing. Mayo Clinic College of Medicine; Estados UnidosFil: Rumie Vittar, Natalia Belen. Mayo Clinic College of Medicine; Estados Unidos. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Biología Molecular. Sección Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: De Andrade, Mariza. Mayo Clinic College of Medicine; Estados UnidosFil: Mukhopadhyay, Debabrata. Mayo Clinic College of Medicine; Estados UnidosFil: Petersen, Gloria M.. Mayo Clinic College of Medicine; Estados UnidosFil: Fernandez Zapico, Martin Ernesto. Mayo Clinic College of Medicine; Estados UnidosFil: Logsdon, Craig D.. University of Texas Health Science Center at Houston. University of Texas Md Anderson Cancer Center; Estados UnidosFil: Chari, Suresh T.. Mayo Clinic College of Medicine; Estados Unido

    First measurement of the Gerasimov-Drell-Hearn integral for Hydrogen from 200 to 800 MeV

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    A direct measurement of the helicity dependence of the total photoabsorption cross section on the proton was carried out at MAMI (Mainz) in the energy range 200 < E_gamma < 800 MeV. The experiment used a 4π\pi detection system, a circularly polarized tagged photon beam and a frozen spin target. The contributions to the Gerasimov-Drell-Hearn sum rule and to the forward spin polarizability γ0\gamma_0 determined from the data are 226 \pm 5 (stat)\pm 12(sys) \mu b and -187 \pm 8 (stat)\pm 10(sys)10^{-6} fm^4, respectively, for 200 < E_\gamma < 800 MeV.Comment: 6 pages, 3 figures, 3 table
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