713 research outputs found
Wheat classification exercise, using 11 June 1973, ERTS MSS data for Fayette County, Illinois (for CITARS task)
The prime emphasis was on classification of pixels in field centers, away from boundary effects. Results were encouraging in both training and test field centers for wheat and other major types of vegetation present. However, the location of fields was found to be a serious problem and it was even more difficult to select field-center pixels for fields of sizes less than 20 acres (or even larger, depending upon field shape) for use in the field-center analysis. The majority of fields in the segment are less than 20 acres in size. ERTS-1 data were received on 12 September 1973. Ground truth information and aerial photography were received on 9 and 15 September. The data were analyzed and processed digitally using the ERIM multispectral software system
Viscous instabilities in flowing foams: A Cellular Potts Model approach
The Cellular Potts Model (CPM) succesfully simulates drainage and shear in
foams. Here we use the CPM to investigate instabilities due to the flow of a
single large bubble in a dry, monodisperse two-dimensional flowing foam. As in
experiments in a Hele-Shaw cell, above a threshold velocity the large bubble
moves faster than the mean flow. Our simulations reproduce analytical and
experimental predictions for the velocity threshold and the relative velocity
of the large bubble, demonstrating the utility of the CPM in foam rheology
studies.Comment: 10 pages, 3 figures. Replaced with revised version accepted for
publication in JSTA
Recent Advances Concerning Certain Class of Geophysical Flows
This paper is devoted to reviewing several recent developments concerning
certain class of geophysical models, including the primitive equations (PEs) of
atmospheric and oceanic dynamics and a tropical atmosphere model. The PEs for
large-scale oceanic and atmospheric dynamics are derived from the Navier-Stokes
equations coupled to the heat convection by adopting the Boussinesq and
hydrostatic approximations, while the tropical atmosphere model considered here
is a nonlinear interaction system between the barotropic mode and the first
baroclinic mode of the tropical atmosphere with moisture.
We are mainly concerned with the global well-posedness of strong solutions to
these systems, with full or partial viscosity, as well as certain singular
perturbation small parameter limits related to these systems, including the
small aspect ratio limit from the Navier-Stokes equations to the PEs, and a
small relaxation-parameter in the tropical atmosphere model. These limits
provide a rigorous justification to the hydrostatic balance in the PEs, and to
the relaxation limit of the tropical atmosphere model, respectively. Some
conditional uniqueness of weak solutions, and the global well-posedness of weak
solutions with certain class of discontinuous initial data, to the PEs are also
presented.Comment: arXiv admin note: text overlap with arXiv:1507.0523
Randomised trials of 6 % tetrastarch (hydroxyethyl starch 130/0.4 or 0.42) for severe sepsis reporting mortality: systematic review and meta-analysis.
Cytogenetic profiles in multiple myeloma and monoclonal gammopathy of undetermined significance: a study in highly purified aberrant plasma cells
This is an open-access paper.Cytogenetic studies in clonal plasma cell disorders have mainly been done in whole bone marrow or CD138+ microbead-enriched plasma cells and suggest that recurrent immunoglobulin heavy chain translocations - e.g. t(4;14) - are primary oncogenetic events. The aim of this study was to determine cytogenetic patterns of highly purified aberrant plasma cells (median purity ≥98%) in different clonal plasma cell disorders. We analyzed aberrant plasma cells from 208 patients with multiple myeloma (n=148) and monoclonal gammopathy of undetermined significance (n=60) for the presence of del(13q14), del(17p13) and t(14q32) using multicolor interphase fluorescence in situ hybridization. Additionally, immunoglobulin heavy chain gene arrangements were analyzed and complementarity determining region 3 was sequenced in a subset of patients and combined multicolor interphase fluorescence in situ hybridization/immunofluorescent protein staining analyses were performed in selected cases to confirm clonality and cytogenetic findings. At diagnosis, 96% of cases with multiple myeloma versus 77% of monoclonal gammopathy of undetermined significance cases showed at least one cytogenetic alteration and/or hyperdiploidy. The cytogenetic heterogeneity of individual cases reflected coexistence of cytogenetically-defined aberrant plasma cell clones, and led to the assumption that karyotypic alterations were acquired stepwise. Cases of multiple myeloma and monoclonal gammopathy of undetermined significance frequently showed different but related cytogenetic profiles when other cytogenetic alterations such as deletions/gains of the immunoglobulin heavy chain or the fibroblast growth factor receptor 3 were additionally considered. Interestingly, in 24% of multiple myeloma versus 62% of monoclonal gammopathy of undetermined significance patients with an immunoglobulin heavy chain translocation, aberrant plasma cells with and without t(14q32) coexisted in the same patient. Our data suggest that recurrent immunoglobulin heavy chain translocations might be absent in the primordial plasma cell clone in a significant proportion of patients with clonal plasma cell disorders carrying these cytogenetic alterations.This work was partially supported by grants from the Fundacion Memoria de Don Samuel Solorzano Barruso, Salamanca, Spain (FS/4-2010). The authors would also like to thank the Dr. Werner Jackstädt Foundation (Wuppertal, Germany) for grant supporting the work of Martin Schmidt-Hieber. The authors would like to thank the Cooperative Research Thematic Network (RTICs; RTICC RD06/0020/0035, RD06/0020/0006 and G03/136), MM Jevitt, SL firm, Instituto de Salud Carlos III/Subdirección General de Investigación Sanitaria (FIS: PI060339; 02/0905; 01/0089/01-02; PS09/01897) and Gerencia Regional de Salud de Castilla y León; Ayuda de Excelencia de Castilla y León, Consejeria de Educación (EDU/894/2009, GR37), and Consejería de Sanidad (557/A/10), Junta de Castilla y León, Valladolid, Spain for supporting this study. JMS is supported by a grant (CP05/00321) from the ISCIII, Ministerio de Ciencia e Innovacion, Madrid, Spain.Peer Reviewe
Studies of the dose-effect relation
Dose-effect relations and, specifically, cell survival curves are surveyed with emphasis on the interplay of the random factors — biological variability, stochastic reaction of the cell, and the statistics of energy deposition —that co-determine their shape. The global parameters mean inactivation dose, , and coefficient of variance, V, represent this interplay better than conventional parameters. Mechanisms such as lesion interaction, misrepair, repair overload, or repair depletion have been invoked to explain sigmoid dose dependencies, but these notions are partly synonymous and are largely undistinguishable on the basis of observed dose dependencies. All dose dependencies reflect, to varying degree, the microdosimetric fluctuations of energy deposition, and these have certain implications, e.g. the linearity of the dose dependence at small doses, that apply regardless of unresolved molecular mechanisms of cellular radiation action
a randomized, open, multicenter phase III trial of lenalidomide/dexamethasone versus lenalidomide/dexamethasone plus subsequent autologous stem cell transplantation and lenalidomide maintenance in patients with relapsed multiple myeloma
Background Despite novel therapeutic agents, most multiple myeloma (MM)
patients eventually relapse. Two large phase III trials have shown
significantly improved response rates (RR) of lenalidomide/dexamethasone
compared with placebo/dexamethasone in relapsed MM (RMM) patients. These
results have led to the approval of lenalidomide for RMM patients and
lenalidomide/dexamethasone has since become a widely accepted second-line
treatment. Furthermore, in RMM patients consolidation with high-dose
chemotherapy plus autologous stem cell transplantation has been shown to
significantly increase progression free survival (PFS) as compared to
cyclophosphamide in a phase III trial. The randomized prospective ReLApsE
trial is designed to evaluate PFS after lenalidomide/dexamethasone induction,
high-dose chemotherapy consolidation plus autologous stem cell transplantation
and lenalidomide maintenance compared with the well-established
lenalidomide/dexamethasone regimen in RMM patients. Methods/Design ReLApsE is
a randomized, open, multicenter phase III trial in a planned study population
of 282 RMM patients. All patients receive three lenalidomide/dexamethasone
cycles and - in absence of available stem cells from earlier harvesting -
undergo peripheral blood stem cell mobilization and harvesting. Subsequently,
patients in arm A continue on consecutive lenalidomide/dexamethasone cycles,
patients in arm B undergo high dose chemotherapy plus autologous stem cell
transplantation followed by lenalidomide maintenance until discontinuation
criteria are met. Therapeutic response is evaluated after the 3rd (arm A + B)
and the 5th lenalidomide/dexamethasone cycle (arm A) or 2 months after
autologous stem cell transplantation (arm B) and every 3 months thereafter
(arm A + B). After finishing the study treatment, patients are followed up for
survival and subsequent myeloma therapies. The expected trial duration is 6.25
years from first patient in to last patient out. The primary endpoint is PFS,
secondary endpoints include overall survival (OS), RR, time to best response
and the influence of early versus late salvage high dose chemotherapy plus
autologous stem cell transplantation on OS. Discussion This phase III trial is
designed to evaluate whether high dose chemotherapy plus autologous stem cell
transplantation and lenalidomide maintenance after lenalidomide/dexamethasone
induction improves PFS compared with the well-established continued
lenalidomide/dexamethasone regimen in RMM patients. Trial registration:
ISRCTN16345835 (date of registration 2010-08-24)
Histological and immunohistochemical features of the spleen in persistent polyclonal B-cell lymphocytosis closely mimic splenic B-cell lymphoma
Persistent polyclonal B-cell lymphocytosis (PPBL) is rare and intriguing hematological disorder predominantly reported in young to middle- aged smoking women. It is characterized by persistent moderate polyclonal B-cell lymphocytosis with circulating hallmark binucleated lymphocytes and elevated polyclonal serum IgM. Most patients have benign clinical course on long-term follow-up. Some pathologic features of PPBL may resemble malignant lymphoma, including morphology as well as frequent cytogenetic and molecular abnormalities. Significant symptomatic splenomegaly requiring splenectomy is very unusual for this disorder; therefore there is a lack of descriptions of the morphologic features of the spleen in the literature. We present here one of the first detailed descriptions of the morphologic and immunohistochemical features of the spleen from a young female with PPBL who developed massive splenomegaly during 6-year follow up. Splenectomy was performed for symptomatic relief and suspicion of malignant process. The morphological and immunohistochemical features of the spleen closely mimicked involvement by B-cell lymphoma, however there was no monotypic surface light chain restriction seen by flow cytometry and no clonal rearrangement of IgH gene was detected by molecular analysis. Evaluating a splenectomy sample in cases like this may present a diagnostic challenge to pathologists. Therefore, correlation with B cell clonality studies (by flow cytometry and molecular analysis), clinical findings and peripheral blood morphology searching for characteristic binucleated lymphocytes is essential to avoid misdiagnosing this benign process as B-cell lymphoma. We also present here a literature review on pathogenesis of PPBL
Radiation-induced cell transformation: transformation efficiencies of different types of ionizing radiation and molecular changes in radiation transformants and tumor cell lines
This study aims to compare the efficiencies of 5.4 keV soft X-rays, alpha-particles, and gamma-rays in transforming C3H 10T1/2 cells and to assess the sequence of cellular and molecular changes during the process of radiation-induced transformation of Syrian hamster embryo (SHE) cells. The somewhat more densely ionizing soft X-rays are more effective than gamma-rays both for cell inactivation and cell transformation. The relative biological effectiveness (RBE) appears to be independent of dose; it is approximately 1.3 for either end point. The RBE of alpha-particles versus gamma-rays, on the other hand, increases with decreasing dose; the dose dependence is somewhat more apparent for cell transformation than for cell inactivation. SHE cells transformed by different types of ionizing radiation and related tumor cell lines isolated from nude mice tumors were found to have a distinct growth advantage compared to primary SHE cells, documented by higher plating efficiencies, shorter doubling times, and higher cloning efficiencies in semisolid medium. Most transformed and tumor cell lines that were investigated have elevated mRNA levels for the H-ras gene, some of them show restriction fragment length polymorphisms of the H-ras gene, and some exhibit a substantially amplified c-myc gene. In a sequence analysis of the Syrian hamster H-ras gene of eight tumor cell lines from radiation transformants, we have not found any mutation in codons 12, 13, 59, 61, nor in the flanking regions of these codons. The transformed and tumor cell lines tend to have lower chromosome numbers than primary SHE cells
Glycogen-inspired trimannosylated serum albumin nanocarriers for targeted delivery of toll-like receptor 7/8 agonists to immune cells and liver
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