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Sample records for beta2-microglobulin quantitatively characterized

  1. Interconverting conformations of variants of the human amyloidogenic protein beta2-microglobulin quantitatively characterized by dynamic capillary electrophoresis and computer simulation

    DEFF Research Database (Denmark)

    Heegaard, Niels H H; Jørgensen, Thomas J D; Cheng, Lei;

    2006-01-01

    Capillary electrophoretic separation profiles of cleaved variants of beta2-microglobulin (beta2m) reflect the conformational equilibria existing in solutions of these proteins. The characterization of these equilibria is of interest since beta2m is responsible for amyloid formation in dialysis......-related amyloidosis and thus is able to attain alternative conformations that lead to irreversible aggregation and precipitation. In this study, we quantitate the increased conformational instability of cleaved beta2m by extracting rate constants and activation energies by simulating the experimental data using...

  2. Congophilicity (Congo red affinity) of different beta2-microglobulin conformations characterized by dye affinity capillary electrophoresis

    DEFF Research Database (Denmark)

    Heegaard, N H; Sen, J W; Nissen, Mogens Holst

    2000-01-01

    The amyloidogenic protein beta-microglobulin was characterized by affinity capillary electrophoresis (CE). CE could separate conformational variants of beta2-microglobulin and with the amyloid-specific dye Congo red as a buffer additive it was possible to measure different Congo red-affinities of......The amyloidogenic protein beta-microglobulin was characterized by affinity capillary electrophoresis (CE). CE could separate conformational variants of beta2-microglobulin and with the amyloid-specific dye Congo red as a buffer additive it was possible to measure different Congo red......-affinities of native and abnormally folded beta2-microglobulin. We find that native beta2-microglobulin has an intermediate affinity for Congo red at pH 7.3 and that binding involves electrostatic interactions. The conformational variant of beta2-microglobulin that appears in acetonitrile solutions binds Congo red...... more strongly. Affinity CE using Congo red as a buffer additive is a new, simple, fast, and quantitative micromethod for the characterization of soluble conformational intermediates of amyloidogenic proteins....

  3. Structural and conformational variants of human beta2-microglobulin characterized by capillary electrophoresis and complementary separation methods

    DEFF Research Database (Denmark)

    Heegaard, Niels H H; Rovatti, Luca; Nissen, Mogens H;

    2003-01-01

    of capillary temperature, organic solvent concentration, and analysis time. The results suggest that the apparent beta2-microglobulin heterogeneity observed by CE is caused by two distinct protein conformations that are present in beta2-microglobulin under partly denaturing conditions and that Met99-oxidized......The small (Mr = 11729) serum protein beta2-microglobulin is prone to precipitate as amyloid in a protein conformational disorder (PCD) that occurs in a significant number of patients on chronic hemodialysis. Analyses by capillary electrophoresis (CE) were undertaken to study beta2-microglobulin...... and normal (i.e. nonoxidized) beta2-microglobulin behave similarly with respect to the potential to attain this alternative conformation. CE is an attractive method to study early and intermediate soluble folding variants that may be involved in PCDs and CE thus may have an important role as a tool...

  4. Expression and characterization of recombinant single-chain salmon class I MHC fused with beta2-microglobulin with biological activity

    DEFF Research Database (Denmark)

    Zhao, Heng; Stet, René J M; Skjødt, Karsten;

    2008-01-01

    Heterodimeric class I major histocompatibility complex (MHC) molecules consist of a putative 45-kDa heavy chain and a 12-kDa beta2-microglobulin (beta2m) light chain. The knowledge about MHC genes in Atlantic salmon accumulated during the last decade has allowed us to generate soluble and stable...... antibodies were successfully produced against both the MHC class I heavy chain and beta(2)m, and showed binding to the recombinant molecule. The recombinant complex Sasabeta2mUBA*0301 was expressed and isolated; the production was scaled up by adjusting to its optimal conditions. Subsequently...

  5. Quantitative analysis of beta-actin, beta-2-microglobulin and porphobilinogen deaminase mRNA and their comparison as control transcripts for RT-PCR.

    Science.gov (United States)

    Lupberger, J; Kreuzer, K A; Baskaynak, G; Peters, U R; le Coutre, P; Schmidt, C A

    2002-02-01

    Quantitation of target mRNAs using the reverse-transcription polymerase chain reaction found a widespread field of application in diverse biomedical diagnostic assays. However, the problem of varying sample quality has to be solved by correcting target molecule amounts through detection of an endogenous control template. The choice of an appropriate reference gene is still object of debate as pseudogene co-amplification and expression level variations may limit the usefulness of some currently used reference reactions. We compared quantitative expression levels of the commonly used endogenous reference genes beta-actin (beta-actin), beta-2-microglobulin (beta2-MG) and porphobilinogen deaminase (PBDG) using the TaqMan chemistry. With these assays we investigated the respective expression patterns in K562 cells and leucocytes of normal individuals as well as of malignoma patients. In K562 cells 1544+246 beta-actin, 65+30 beta2-MG and 22+/-8 PBDG copies/cell were detected. In normal leucocytes 491+/-97 beta-actin, 40+/-17 beta2-MG and <1 PBDG copies/cell were quantified. Leucocytes of various malignancies exhibited 84+/-51 beta-actin, 106+/-8 beta2-MG and <1 PBDG copies/cell. We conclude that beta2-MG is the most suitable reference gene tested as its variation between different sample origins and within distinct cell types was acceptable low.

  6. Cleaved beta 2-microglobulin partially attains a conformation that has amyloidogenic features

    DEFF Research Database (Denmark)

    Heegaard, Niels H H; Roepstorff, Peter; Melberg, Steen G;

    2002-01-01

    beta(2)-Microglobulin, a small protein localized in serum and on cell surfaces, can adopt specific aggregating conformations that generate amyloid in tissues and joints as a complication to long-term hemodialysis. We characterize a proteolytic variant of beta(2)-microglobulin (cleaved after Lys(58...... while appearing homogeneous, except for a fraction of oxidized species detected by other techniques. The two components had different binding affinities for heparin and for the amyloid-specific dye Congo red, and the equilibrium between the two forms was dependent on solvent conditions. Together...... with analysis of the differences in circular dichroism, the results suggest that beta(2)-microglobulin cleaved after Lys(58) readily adopts two equilibrium conformations under native conditions. In the cleaved and trimmed beta(2)-microglobulin that appears in vivo, the less populated conformation...

  7. Increased expression of beta 2-microglobulin and histocompatibility antigens on human lymphoid cells induced by interferon

    DEFF Research Database (Denmark)

    Hokland, M; Heron, I; Berg, K

    1982-01-01

    Normal human peripheral blood lymphocytes were incubated in the presence of different concentrations of interferon for various incubation periods. Subsequently, the amount of beta 2-Microglobulin and HLA-A, B and C surface antigens was estimated by means of quantitative immunofluorescence (flow c...

  8. [Beta 2 microglobulin in children with neuroinfections].

    Science.gov (United States)

    Murawska, E; Szychowska, Z; Jarno, A

    1997-01-01

    CSF and plasma beta2 microglobulin (B2M) concentrations were determined by an enzyme linked fluorescent assay (ELFA) (Vidas-bioMerieux) in children with bacterial (B2M), viral (mumps and enteroviral) meningitis and in the controls. CSF B2M concentrations in children with B2M at admission, at 24-48 hrs of treatment and at recovery (day 10), in children with viral meningitis at admission and at recovery were significantly higher in comparison with the control group of children with non-pleiocytic CSF. The levels of CSF B2M at 24-48 hrs of treatment of B2M cases were significantly higher than those at the beginning of both mumps and enteroviral meningitis cases which may be helpful in differential diagnosis of meningitis, especially in cases of retarded diagnosis or partially treated B2M. Plasma levels of B2M during bacterial and mumps meningitis did not differ from those in healthy children but in children with enteroviral meningitis were significantly higher. There was a positive correlation between CSF B2M at the beginning of B2M and some laboratory findings of inflammatory response (CRP, ERS). The CSF B2M levels were significantly higher than its plasma levels in patients with B2M at 24-48 hours (second stage) of disease, mumps meningitis on admission and recovery which may suggest intrathecal production of B2M during central nervous system infection.

  9. Beta-2-Microglobulin in Autism Spectrum Disorders

    Directory of Open Access Journals (Sweden)

    Paula Goines

    2007-01-01

    Full Text Available Autism spectrum disorders (ASD are heterogeneous neurodevelopmental diseases of unknown etiology. There are no biological markers for ASD and current diagnosis is based on behavioral criteria. Recent data has shown that MHC I, a compound involved in adaptive immune function, is also involved in neurodevelopment, synaptic plasticity and behavior. It has been suggested that altered MHC I expression could play a part in neurodevelopmental diseases like ASD. To address this possibility, we measured plasma levels of beta-2-microglobulin (β2m, a molecule that associates with MHC I and is indicative of MHC I expression, in 36 children with autism, 28 typically developing controls and subjects with developmental disabilities (n=16 but not autism. The age range of our study population was 17-120 months. We found no statistically significant differences in plasma ß 2m levels between groups. Therefore, plasma levels of ß2m measured in early childhood in autism may not reflect changes in MHC class I in autism.

  10. 99mTc-MIBI scintigraphy and beta-2-microglobulin in patients with multiple myeloma

    International Nuclear Information System (INIS)

    Multiple myeloma is malignancy characterizing with autoimmune proliferation of malignant plasma cells. The aim of the study was to investigate the clinical usefulness of 99mTc-MIBI scintigraphy and serum beta-2-microglobulin for diagnosis, staging and therapy control in patients with multiple myeloma. 67 patients with multiple myeloma were investigated. 42 patients ware in active state and 25 patients were in remission. Planar images and/ or SPECT were performed on the rotating gamma camera (Siemens) 30 minutes and 3 hours after i.v. injection of 555-740 MBq 99mTc-MIBI. The uptake patterns were grouped as normal, diffusely increased and focal increased. Beta-2-microglobulin levels were measured by radioimmunoassay. The scintigraphy with 99mTc-MIBI was true positive in 40 patients with MM. From them, 21 patients were with diffuse uptake and 19 were with focal uptake with 29 lesions. 99mTc-MIBl marrow uptake correlated with the percentage of bone marrow plasma cells. All samples from patients in active state had a serum beta-2-microglobulin above the normal range. In two patients with false negative scan, the results were compared with the data of CT images. Positive clinical findings and increased value of tumour marker were found in these patients. One patient was with false positive scintigraphy. After therapy, the scintigraphy was true negative in 25 patients. In these patients in remission, the levels of the serum beta-2-microglobulin were near to the normal levels. In conclusion, our results demonstrated the effectiveness of both methods - 99mTc-MIBI scintigraphy and serum beta-2-microglobulin in different stage of the disease for the diagnosis, staging and therapy control by patients with multiple myeloma. (authors)

  11. The effect of surgery on the renal excretion of beta 2-microglobulin.

    Science.gov (United States)

    Walenkamp, G H; Vree, T B; Guelen, P J; Jongman-Nix, B

    1983-03-28

    Surgical trauma causes an increase in the renal excretion rate of beta 2-microglobulin whilst creatinine excretion is not influenced. The increase in the renal excretion rate of beta 2-microglobulin is probably the result of an increased release of beta 2-microglobulin by the cells which exceeds a maximum in the active tubular reabsorption of the compound by the proximal tubule cell. The renal excretion of beta 2-microglobulin is proportional to the relative clinical trauma score. PMID:6189646

  12. Amino acid sequences and structures of chicken and turkey beta 2-microglobulin

    DEFF Research Database (Denmark)

    Welinder, K G; Jespersen, H M; Walther-Rasmussen, J;

    1991-01-01

    to human beta 2-microglobulin at 46 and 47 positions, respectively, and to bovine beta 2-microglobulin at 47 positions, i.e. there is about 47% identity between avian and mammalian beta 2-microglobulins. The known X-ray crystallographic structures of bovine beta 2-microglobulin and human HLA-A2 complex...... suggest that the seven chicken to turkey differences are exposed to solvent in the avian MHC class I complex. The key residues of beta 2-microglobulin involved in alpha chain contacts within the MHC class I molecule are highly conserved between chicken and man. This explains that heterologous human beta 2...

  13. Enhanced expression of beta2-microglobulin and HLA antigens on human lymphoid cells by interferon

    DEFF Research Database (Denmark)

    Heron, I; Hokland, M; Berg, K

    1979-01-01

    Mononuclear cells from the blood of healthy normal humans were kept in cultures under nonstimulating conditions for 16 hr in the presence or absence of human interferon. The relative quantities of HLA antigens and beta(2)-microglobulin on the cultured cells were determined by quantitative...... was observed on B- and T-enriched lymphocyte populations and was found to be dose dependent with the optimum with "physiological" concentrations of interferon. Pretreatment of lymphocytes with interferon for 2 hr was found to be as effective as having interferon present during the total culture period...

  14. Beta 2-Microglobulin clearance as measured by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Woo, J.; Floyd, M.; Longley, M.A.; Cannon, D.C.

    1980-07-01

    We describe a radioimmunoassay for beta 2-microglobulin (beta 2 mu) in serum and urine. We incubated aliquots of diluted samples at room temperature for 1 h with /sup 125/I-labeled beta 2 mu and a rabbit antiserum monospecific for human beta 2 mu, and separated the phases by the double-antibody technique. The logit-log transformed dose-response curve was linear in the range 2 to 64 ng, equivalent to 0.5 to 16 mg/L of serum and 0.5 to 320 mg/L of urine. Assay sensitivity was 2.4 ng of beta 2 mu. Validation studies included tests of precision, accuracy, antibody specificity, and parallelism of the dose-response curves for standard and unknown. In a study of 25 normal individuals, serum and urine beta 2 mu ranged from 1.1 to 2.3 mg/L and 40 to 360 micrograms/24 h; the clearance of beta 2 mu was 8 to 130 microL/min. In 21 renal allograft recipients tested one to five weeks after transplantation, serum and urine beta 2 mu ranged from 3.9 to 15.6 mg/L and 7.2 to 611 mg/24 h; beta 2 mu clearance was 0.60 to 33.3 mL/min. Values for both serum and urine correlated well with severity of allograft rejection.

  15. A simple method for the preparation and purification of C1 complement cleaved beta 2-microglobulin from human serum

    DEFF Research Database (Denmark)

    Nissen, Mogens Holst; Johansen, B; Bjerrum, Ole Jannik

    1997-01-01

    dissolving the precipitate containing the C1 complement in Tris-HCl buffer, pH 7.6, efficient conversion of added beta 2-microglobulin to desLys58 beta 2-microglobulin was observed. Addition of a specific carboxypeptidase B inhibitor (Plummers inhibitor) could partly prevent the deletion of Lys-58 from...... cleaved beta 2-microglobulin, whereby Lys58-cleaved beta 2-microglobulin was obtained. The proteolytically processed forms were subsequently purified by G-75 Sephadex gel filtration followed by chromatofocusing. A yield of 10-40% of proteolytically processed beta 2-microglobulin was obtained. Only one...

  16. Clearance of beta-2-microglobulin and middle molecules in haemodiafiltration.

    Science.gov (United States)

    Tattersall, James

    2007-01-01

    Middle molecules, consisting mostly of peptides and small proteins with molecular weight the range of 500-60,000 Da, accumulate in renal failure and contribute to the uraemic toxic state. Beta2-microglobulin (beta2-MG) with a molecular weight of 11,000 is considered representative of these middle molecules. These solutes are not well cleared by low-flux dialysis. High-flux dialysis will clear middle molecules, partly by internal filtration. This convective component of high-flux dialysis can be enhanced in a predictable way by haemodiafiltration (HDF). The convective and diffusive clearance rates of any middle molecule across any haemodiafilter can be predicted from known or measurable factors such as its sieving coefficient, bound fraction and molecular weight. The removal of middle molecules is also influenced by factors within the patient. Beta2-MG is distributed within the extracellular fluid. During HDF, beta2-MG must transfer into the intravascular compartment across the capillary walls. This transcapillary transfer at a rate of approximately 100 ml/min slows beta2-MG removal from the body. Continuing transfer after the end of a treatment session results in a significant rebound of beta2-MG levels. This intercompartment transfer and its effect on beta2-MG clearance and concentration can be predicted by a 2-compartment model. By extrapolation, the behaviour of other middle molecules can be predicted. The 2-compartment model, which takes non-dialytic beta2-MG clearance at a rate of 3 ml/min and beta2-MG generation at a rate of 0.1 mg/min into account, can predict the effect of any HDF schedule on beta2-MG levels. Low-flux dialysis results in a beta2-MG level of around 40 mg/l. Three times weekly, 4-hour HDF can reduce beta2-MG levels to around 20 mg/l. Long (nocturnal) HDF can reduce beta2-MG levels to around 10 mg/l, compared to physiological levels of less than 5 mg/l.

  17. Rapidly reversible albumin and beta 2-microglobulin hyperexcretion in recent severe essential hypertension

    DEFF Research Database (Denmark)

    Christensen, Cramer

    1983-01-01

    with ensuing fall in blood pressure was rapidly and almost completely reversible in all but one patient during conventional treatment and the increased beta 2-microglobulin excretion was totally reversible in all but one patient. Both albumin and beta 2-microglobulin excretion rate were positively correlated......Seven young patients with newly diagnosed severe hypertension were studied for one week. The mean age was 34.9 years (range 28-44). The mean initial values +/- s.d. for systolic and diastolic pressures were 223 +/- 27 and 141 +/- 8 mmHg, respectively. Secondary hypertension was excluded...... by conventional methods and serum creatinine was normal. A pronounced but quite variably elevated albumin excretion 440 +/- 448 micrograms/min (mean +/- s.d.) and a moderately increased beta 2-microglobulin excretion 3.06 +/- 3.29 micrograms/min was noted before treatment. The abnormal albumin excretion...

  18. Interaction between the renal excretion rates of beta 2-microglobulin and tobramycin in man.

    Science.gov (United States)

    Vree, T B; Zweens, K; Huige, P J; Guelen, P J; Jongman-Nix, B

    1984-03-27

    The renal excretion rate of beta 2-microglobulin in man is 127 +/- 98 ng/min at alkaline urine pH (pH 7). Tobramycin, up to intravenous doses of 160 mg (2 mg/kg) does not increase the renal excretion rate of beta 2-microglobulin. Tobramycin must have less affinity than gentamicin for the tubular system for active reabsorption of amino groups containing organic compounds. Due to this reduced affinity tobramycin will be absorbed less by the proximal tubular cells, which may be one of the reasons for tobramycin being less toxic than gentamicin. beta 2-Microglobulin excretion can be used as a parameter for the relative binding affinity of aminoglycosides. PMID:6370509

  19. Isolation and characterization of chicken and turkey beta 2-microglobulin

    DEFF Research Database (Denmark)

    Skjødt, K; Welinder, K G; Crone, M;

    1986-01-01

    Chicken and turkey beta 2-m were isolated from citrated plasma in sequential use of three chromatographic steps: affinity chromatography, gel filtration chromatography and anion-exchange chromatography. The purified protein was identified as beta 2-m by reaction with a beta 2-m specific monoclonal...... antibody and by the ability to recombine with the chicken MHC class I heavy chain. The purity was estimated by SDS-PAGE and IEF. The pI was between 5.1 and 5.3 for chicken beta 2-m and 4.7 and 4.8 for turkey beta 2-m, which fact is reflected in their different electrophoretic mobilities in agarose gel...... (turkey migrates in the alpha and chicken migrates in the beta region). The mol. wt of both chicken and turkey beta 2-m was 14,500 estimated by SDS-PAGE whereas calculations based on the amino acid compositions gave mol. wts of 11,000. EM280 was 15.9 for chicken beta 2-m and 16.4 for turkey beta 2-m...

  20. Renal handling of beta-2-microglobulin, amylase and albumin in acute pancreatitis.

    Science.gov (United States)

    Karlsson, F A; Jacobson, G

    1979-01-01

    The renal handling of beta-2-microglobulin, amylase and albumin was studied in patients with acute pancreatitis. The data were compared with results obtained from patients with glomerular proteinuria and from patients with tubular proteinuria. Initially during acute pancreatitis, the clearance ratio (clearance protein/clearance creatinine) for beta-2-microglobulin was increased dramatically (77-fold) compared to normals. After four to seven days this ratio had fallen and was elevated only 7-fold. The corresponding figures for amylase were 3.3 and 1.8 times and for albumin 9 and 5 times respectively. In glomerular disease, the clearance ratios for beta-2-microglobulin, amylase and albumin were increased 6, 1.1, and 154 times and in tubular disease 448, 1.1, and 28 times, respectively. The electrophoretic pattern of the urinary proteins during pancreatitis was mostly normal. In a few cases, slight tubular proteinuria was noticed. Amylase activity in serum and urine from patients with pancreatitis was found to sediment, (S20,W = 4.6) in a sucrose gradient, identical to amylase from normal serum and urine. The marked increase in the excretion of beta-2-microglobulin probably reflects interference of the kidney function at the proximal tubular level. Determinations of this protein in urine may be of value in studies of kidney dysfunction that can accompany pancreatitis.

  1. Quantification of cleaved beta2-microglobulin in serum from patients undergoing chronic hemodialysis

    DEFF Research Database (Denmark)

    Corlin, Dorthe B; Sen, Jette W; Ladefoged, Søren;

    2005-01-01

    BACKGROUND: Patients on chronic hemodialysis are prone to develop amyloid deposits of misfolded beta(2)-microglobulin (beta(2)M) in osteoarticular tissues. beta(2)M with various deletions/truncations and chemical modifications has been found together with structurally intact beta(2)M in extracts...

  2. Urinary albumin and beta 2-microglobulin excretion rates in patients with systemic lupus erythematosus

    DEFF Research Database (Denmark)

    Parving, H H; Sørensen, S F; Mogensen, C E;

    1980-01-01

    The daily urinary albumin and beta 2-microglobulin excretion rates were measured with sensitive radioimmunoassays in 14 patients with systemic lupus erythematosus (SLE). The duration of SLE ranged from 0.5 to 18 years, mean 10 years. The mean age was 37 years. All patients except 5 received...

  3. Beta 2-microglobulin in urine and serum determined by a micro-ELISA technique

    DEFF Research Database (Denmark)

    Feldt-Rasmussen, B; Deckert, M; Dinesen, B

    1986-01-01

    An enzyme-linked immunoadsorbent assay for the determination of beta 2-microglobulin in serum and urine using microtest plates as solid phase is described. All reagents are commercially available. The assay has a high capacity and it is inexpensive using only 3% of the amounts of antibodies...

  4. Spontaneous inflammatory arthritis in HLA-B27 transgenic mice lacking beta 2-microglobulin: a model of human spondyloarthropathies

    OpenAIRE

    1995-01-01

    Human class I major histocompatibility complex allele HLA-B27 is associated with a group of human diseases called "spondyloarthropathies." Studies on transgenic rats expressing HLA-B27 and human beta 2-microglobulin have confirmed the role of HLA-B27 in disease pathogenesis. Here we report spontaneous inflammatory arthritis in HLA-B27 transgenic mice lacking beta 2-microglobulin (B27+ beta 2m-/- ). In the absence of beta 2-microglobulin, B27+ beta 2m-/- animals do not express the HLA-B27 tran...

  5. Cellular expression or binding of desLys58-beta2 microglobulin is not dependent on the presence of the tri-molecular MHC class I complex

    DEFF Research Database (Denmark)

    Wang, M; Corlin, D B; Heegaard, N H H;

    2008-01-01

    increased when cells were pre-incubated with dbeta2m and when TIB-202 cells were exposed to lipopolysaccharide. dbeta2m was also expressed on T leukaemic Jurkat cells as well as on low HLA-expressing erythroleukaemic K562 cells. beta2m gene-deleted murine splenocytes only bound 332-01 after pre......The monoclonal antibody 332-01 is a newly developed antibody which specifically recognizes human desLys58-beta2 microglobulin (dbeta2m). In the present study, we characterized the binding of 332-01 to peripheral blood mononuclear cells (PBMC), a number of human leukaemic and monocytic cell lines...

  6. The relationship between the renal clearance of creatinine and the apparent renal clearance of beta-2-microglobulin in patients with normal and impaired kidney function.

    Science.gov (United States)

    Vree, T B; Guelen, P J; Jongman-Nix, B; Walenkamp, G H

    1981-07-18

    The renal clearances of creatinine and beta 2-microglobulin of patients with either normal or impaired kidney function were measured. The renal clearance of beta 2-microglobulin depends on the urinary pH and must be considered as an apparent renal clearance because after tubular reabsorption the compound is metabolized in the kidney. Impaired kidney function reduces the percentage of tubular reabsorption of beta 2-microglobulin. PMID:6166414

  7. Complement activation by the amyloid proteins A beta peptide and beta 2-microglobulin

    DEFF Research Database (Denmark)

    Nybo, Mads; Nielsen, E H; Svehag, S E

    1999-01-01

    Complement activation (CA) has been reported to play a role in the pathogenesis of Alzheimer's disease (AD). To investigate whether CA may contribute to amyloidogenesis in general, the CA potential of different amyloid fibril proteins was tested. CA induced by A beta preparations containing soluble...... protein, protofilaments and some fibrils or only fibrils in a solid phase system (ELISA) was modest with a slow kinetics compared to the positive delta IgG control. Soluble A beta induced no detectable CA in a liquid phase system (complement consumption assay) while fibrillar A beta caused CA at 200 mg....../ml and higher concentrations. Soluble beta 2-microglobulin (beta 2M) purified from peritoneal dialysates was found to be as potent a complement activator as A beta in both solid and liquid phase systems while beta 2M purified from urine exhibited lower activity, a difference which may be explained...

  8. T cell precursor migration towards beta 2-microglobulin is involved in thymus colonization of chicken embryos

    DEFF Research Database (Denmark)

    Dunon, D; Kaufman, J; Salomonsen, J;

    1990-01-01

    beta 2-microglobulin (beta 2m) attracts hemopoietic precursors from chicken bone marrow cells in vitro. The cell population responding to beta 2m increases during the second period of thymus colonization, which takes place at days 12-14 of incubation. The precursors from 13.5 day old embryos were...... isolated after migration towards beta 2m in vitro and shown to be able to colonize a 13 day old thymus in ovo, where they subsequently acquire thymocyte markers. In contrast these beta 2m responsive precursors did not colonize embryonic bursa, i.e. differentiate into B lymphocytes. During chicken...... embryogenesis, peaks of beta 2m transcripts and of free beta 2m synthesis can only be detected in the thymus. The peak of free beta 2m synthesis in the thymus and the increase of beta 2m responding bone marrow cells both occur concomitantly with the second wave of thymus colonization in chicken embryo, facts...

  9. A beta2-microglobulin cleavage variant fibrillates at near-physiological pH

    DEFF Research Database (Denmark)

    Corlin, Dorthe B; Johnsen, Christina K; Nissen, Mogens H;

    2009-01-01

    several days. Here, we show that amyloid fibrils are generated in less than an hour when a cleavage variant of beta2m--found in the circulation of many dialysis patients--is exposed to pH levels (pH 6.6) occurring in joints during inflammation. Aggregation and fibrillation, including seeding effects......Beta2-microglobulin (beta2m) deposits as amyloid in dialysis-related amyloidosis (DRA), predominantly in joints. The molecular mechanisms underlying the amyloidogenicity of beta2m are still largely unknown. In vitro, acidic conditions, pH ... with intact, native beta2m were studied by Thioflavin T fluorescence spectroscopy, turbidimetry, capillary electrophoresis, and electron microscopy. We conclude that a biologically relevant variant of beta2m is amyloidogenic at slightly acidic pH. Also, only a very small amount of preformed fibrils...

  10. Creatine kinase BB and beta-2-microglobulin as markers of CNS metastases in patients with small-cell lung cancer

    DEFF Research Database (Denmark)

    Pedersen, A G; Bach, F W; Nissen, Mogens Holst;

    1985-01-01

    Creatine kinase (CK) and its BB isoenzyme (CK-BB) were measured in CSF in 65 evaluable patients suspected of CNS metastases secondary to small-cell lung cancer (SCLC). In addition, CSF and plasma levels of beta-2-microglobulin (beta-2-m) were measured in a group of 73 evaluable patients. Of the 65...

  11. [INTERACTION OF THE DYE CONGO RED WITH FIBRILS OF LYSOZYME, BETA2-MICROGLOBULIN AND TRANSTHYRETIN].

    Science.gov (United States)

    Antimonova, O I; Grudinina, N A; Egorov, V V; Polyakov, D S; Iljin, V V; Shavlovsky, M M

    2016-01-01

    By means of spectrophotometric assay we investigated interaction of the dye Congo red (CR) with fibrils of model proteins--hen egg white lysozyme, recombinant human beta2-microglobulin (b2M) and recombinant human transthyretin (TTR). The commercial dye sample was found to contain a significant amount of impurities. Methods for the dye purification are disclosed and CR molar extinction coefficient at 490 nm (ε490) was determined to be 3.3 x 10(4) M(-1) x cm(-1) at pH above 6.0. Formation of the CR-fibril complex results in changes in the dye visible absorption spectrum. According to the data on titration of fibril solutions with excess of the dye, CR binds to lysozyme fibrils at a ratio of about 5 molecules per protein monomer within fibril structure, to b2M fibrils--about 4 molecules per monomer, to TTR fibrils--about 4 molecules per subunit of the protein. PMID:27228663

  12. The Implication and Significance of Beta 2 Microglobulin: A Conservative Multifunctional Regulator

    Institute of Scientific and Technical Information of China (English)

    Ling Li; Mei Dong; Xiao-Guang Wang

    2016-01-01

    Objective: This review focuses on the current knowledge on the implication and significance of beta 2 microglobulin (β2M), a conservative immune molecule in vertebrate.Data Sources: The data used in this review were obtained from PubMed up to October 2015.Terms of β2M, immune response, and infection were used in the search.Study Selections: Articles related to β2M were retrieved and reviewed.Articles focusing on the characteristic and function of β2M were selected.The exclusion criteria of articles were that the studies on β2M-related molecules.Results: β2M is critical for the immune surveillance and modulation in vertebrate animals.The dysregulation of β2M is associated with multiple diseases, including endogenous and infectious diseases.β2M could directly participate in the development of cancer cells, and the level of β2M is deemed as a prognostic marker for several malignancies.It also involves in forming major histocompatibility complex (MHC class Ⅰ or MHC Ⅰ) or like heterodimers, covering from antigen presentation to immune homeostasis.Conclusions: Based on the characteristic of β2M, it or its signaling pathway has been targeted as biomedical or therapeutic tools.Moreover, β2M is highly conserved among different species, and overall structures are virtually identical, implying the versatility of β2M on applications.

  13. Target cell lysis by natural killer cells is influenced by beta 2-microglobulin expression.

    Science.gov (United States)

    Müllbacher, A; King, N J

    1989-07-01

    Natural killer (NK) cells form part of the vertebrate defence against viruses and tumours, but show only limited specificity. The molecule(s) recognized by NK cells on target cells are at present unknown. Major histocompatibility complex (MHC) class I antigen concentration on target cells is inversely correlated with NK cell lysis. Here we show that MHC class I-unassociated beta 2-microglobulin (beta 2-m) expression is involved in NK cell-target cell interaction. Two human MHC class I negative cell lines, Daudi and K562, are differentially susceptible to NK cell lysis. Daudi cells are beta 2-m-negative and resistant to NK lysis, K562 are beta 2-m-positive and highly susceptible to lysis by NK cells. Interferon (IFN) treatment augments beta 2-m expression and NK lysis of K562, but not in Daudi cells. NK cell lysis of K562, but not YAC-1 cells, can be inhibited by monoclonal anti-human beta 2-m antibody. Furthermore, susceptibility of mouse embryo fibroblasts (MEF) to NK lysis can be increased by infection with recombinant vaccinia virus expressing the human beta 2-m gene.

  14. Differential effect on serum neopterin and serum beta 2-microglobulin is induced by treatment in Pneumocystis carinii pneumonia

    DEFF Research Database (Denmark)

    Benfield, T L; Schattenkerk, J K; Hofmann, B;

    1994-01-01

    Forty-three human immunodeficiency virus-infected patients with Pneumocystis carinii pneumonia (PCP) were enrolled in a study of adjunctive corticosteroid treatment for 10 days versus placebo, in addition to antimicrobial treatment. Levels of neopterin and beta 2-microglobulin (beta 2M) were dete...... activation leading to neopterin production and decreased production of beta 2M by lymphocytes. Further, addition of corticosteroids modified and decreased this immune activation and may explain the earlier demonstrated beneficial effect of corticosteroids in PCP treatment....

  15. The Prognostic Significance of Beta2 Microglobulin in Patients with Hemophagocytic Lymphohistiocytosis

    Directory of Open Access Journals (Sweden)

    Tiantong Jiang

    2016-01-01

    Full Text Available Objective. To determine the prognostic significance of beta2 microglobulin (β2-m concentrations in patients with hemophagocytic lymphohistiocytosis (HLH, a rare disorder caused by pathologic activation of the immune system. Patients and Methods. The study population consisted of 74 patients diagnosed with HLH and 35 healthy controls. Serum β2-m levels were measured using a latex agglutination photometric immunoassay. Results. Median serum β2-m levels were significantly higher in HLH patients than in healthy controls (4.05 versus 1.5 mg/L; P<0.001 and were significantly higher in patients with lymphoma associated hemophagocytic syndrome (LAHS than in patients with benign disease-associated HLH (4.2 versus 3.3 mg/L; P<0.001. Higher serum β2-m levels were positively correlated with LAHS (P=0.005, abnormal lactate dehydrogenase concentrations (P=0.009, and hypoalbuminemia (P=0.003. ROC analysis showed that overall survival (OS was significantly shorter in LAHS patients with serum β2-m levels ≥4.03 mg/L compared to <4.03 mg/L (P<0.001. Moreover, multivariate analysis showed that serum β2-m level was an independent prognostic of OS (P=0.034 in patients with LAHS. Conclusion. High serum β2-m levels and LAHS were associated with markedly poorer OS in patients with HLH. Serum β2-m concentration was a powerful and independent prognostic factor for OS in patients with LAHS.

  16. The chicken beta 2-microglobulin gene is located on a non-major histocompatibility complex microchromosome: a small, G+C-rich gene with X and Y boxes in the promoter

    DEFF Research Database (Denmark)

    Riegert, P; Andersen, R; Bumstead, N;

    1996-01-01

    a similar genomic organization but smaller introns and higher G+C content than mammalian beta 2-microglobulin genes. The promoter region is particularly G+C-rich and contains, in addition to interferon regulatory elements, potential S/W, X, and Y boxes that were originally described for mammalian class II......beta 2-Microglobulin is an essential subunit of major histocompatibility complex (Mhc) class I molecules, which present antigenic peptides to T lymphocytes. We sequenced a number of cDNAs and two genomic clones corresponding to chicken beta 2-microglobulin. The chicken beta 2-microglobulin gene has...... but not class I alpha or beta 2-microglobulin genes. There is a single chicken beta 2-microglobulin gene that has little polymorphism in the coding region. Restriction fragment length polymorphisms from Mhc homozygous lines, Mhc congenic lines, and backcross families, as well as in situ hybridization, show...

  17. Beta-2 microglobulin and lactate dehydrogenase levels are useful prognostic markers in early stage primary gastric lymphoma.

    Science.gov (United States)

    Avilés, A; Narváez, B R

    1998-10-01

    The optimal management of primary gastric lymphoma (PGL) remains undecided because a definitive classification for therapeutic decision is not available. The International Index Project has proved to be useful in patients with nodal disease, but in extranodal presentation it has not been tested. We reviewed 297 patients with early stage PGL. They were initially classified according to the prognostic features of the International Index Project. No influence on duration of time to treatment failure (TTF) or overall survival was observed. For this reason we developed a logistical model to identify prognostic factors in patients with early stage PGL. Levels of beta-2 microglobulin and lactic dehydrogenase were observed to have prognostic significance in both univariate and multivariate analysis. With these parameters we constructed a logistical model to identify patients at low risk (TTF = 76%; at 7 years overall survival was 96%), statistically different to patients at high risk (TTF = 34% and overall survival = 22%). The number of patients at intermediate risk were too small to compare with the other groups. Because pathological or other clinical or laboratory prognostic features cannot help in the identification of a prognostic model, we propose that the use beta-2 microglobulin and lactic dehydrogenase can define different groups at risk and develop a prognostic system to define the best therapeutic approach in this patients. PMID:9807677

  18. Alpha-interferon induces enhanced expression of HLA-ABC antigens and beta-2-microglobulin in vivo and in vitro in various subsets of human lymphoid cells

    DEFF Research Database (Denmark)

    Nissen, Mogens Holst; Larsen, J K; Plesner, T;

    1987-01-01

    The effect of cloned alpha-interferon (alpha-IFN) on the in vitro and in vivo expression of HLA-ABC antigens and beta-2-microglobulin (beta-2-m) on subpopulations of human lymphoid cells was studied by flow cytometry. Mononuclear cells isolated from patients and cell cultures were labelled...

  19. Modification of beta 2-microglobulin in serum from patients with small cell carcinoma of the lung--correlation with the clinical course

    DEFF Research Database (Denmark)

    Nissen, Mogens Holst; Plesner, T; Rørth, M

    1984-01-01

    A beta 2-microglobulin (beta 2m) 'modifying activity' has been demonstrated by crossed radioimmunoelectrophoresis of serum. The activity could be estimated by planimetry and expressed in arbitrary units (A.U.). Elevated values of beta 2m 'modifying activity' (greater than 0.30 A.U.) has been demo...

  20. Cellular expression or binding of desLys58-beta2 microglobulin is not dependent on the presence of the tri-molecular MHC class I complex.

    Science.gov (United States)

    Wang, M; Corlin, D B; Heegaard, N H H; Claesson, M H; Nissen, M H

    2008-02-01

    The monoclonal antibody 332-01 is a newly developed antibody which specifically recognizes human desLys58-beta2 microglobulin (dbeta2m). In the present study, we characterized the binding of 332-01 to peripheral blood mononuclear cells (PBMC), a number of human leukaemic and monocytic cell lines, and beta2m gene-deleted murine lymphocytes. dbeta2m was found to be expressed on non-activated and activated monocytes. When cells were pre-exposed to dbeta2m, 332-01 also bound to non-activated T lymphocytes. dbeta2m was expressed on the monocytic cell lines U937 and TIB-202, and binding was significantly increased when cells were pre-incubated with dbeta2m and when TIB-202 cells were exposed to lipopolysaccharide. dbeta2m was also expressed on T leukaemic Jurkat cells as well as on low HLA-expressing erythroleukaemic K562 cells. beta2m gene-deleted murine splenocytes only bound 332-01 after pre-exposure to dbeta2m. Binding of 332-01 antibody could not be displaced by addition of high concentrations of native beta2m. In conclusion, our data indicate that dbeta2m - in contrast to native beta2m - binds to a hitherto unknown cell surface receptor independent of classical MHC class I molecules. As beta2m has previously been shown to display biological activities such as the induction of both growth promotion and apoptosis, C1 complement activity, shown to mediate cleavage of beta2m, could be involved in these processes.

  1. Usefulness of Beta2-Microglobulin as a Predictor of All-Cause and Nonculprit Lesion-Related Cardiovascular Events in Acute Coronary Syndromes (from the PROSPECT Study).

    Science.gov (United States)

    Möckel, Martin; Muller, Reinhold; Searle, Julia; Slagman, Anna; De Bruyne, Bernard; Serruys, Patrick; Weisz, Giora; Xu, Ke; Holert, Fabian; Müller, Christian; Maehara, Akiko; Stone, Gregg W

    2015-10-01

    In the Providing Regional Observations to Study Predictors of Events in the Coronary Tree (PROSPECT) study, plaque burden, plaque composition, and minimal luminal area were associated with an increased risk of adverse cardiovascular events arising from untreated atherosclerotic lesions (vulnerable plaques) in patients with acute coronary syndromes (ACS). We sought to evaluate the utility of biomarker profiling and clinical risk factors to predict 3-year all-cause and nonculprit lesion-related major adverse cardiac events (MACEs). Of 697 patients who underwent successful percutaneous coronary intervention (PCI) for ACS, an array of 28 baseline biomarkers was analyzed. Median follow-up was 3.4 years. Beta2-microglobulin displayed the strongest predictive power of all variables assessed for all-cause and nonculprit lesion-related MACE. In a classification and regression tree analysis, patients with beta2-microglobulin >1.92 mg/L had an estimated 28.7% 3-year incidence of all-cause MACE; C-peptide 1.92 mg/L identified a cohort with a 3-year rate of 18.5%, and C-peptide PROSPECT study, beta2-microglobulin strongly predicted all-cause and nonculprit lesion-related MACE within 3 years after PCI in ACS. C-peptide and HDL provided further risk stratification to identify angiographically mild nonculprit lesions prone to future MACE.

  2. Internalization of coxsackievirus A9 is mediated by {beta}2-microglobulin, dynamin, and Arf6 but not by caveolin-1 or clathrin.

    Science.gov (United States)

    Heikkilä, Outi; Susi, Petri; Tevaluoto, Tuire; Härmä, Heidi; Marjomäki, Varpu; Hyypiä, Timo; Kiljunen, Saija

    2010-04-01

    Coxsackievirus A9 (CAV9) is a member of the human enterovirus B species within the Enterovirus genus of the family Picornaviridae. It has been shown to utilize alphaV integrins, particularly alphaVbeta6, as its receptors. The endocytic pathway by which CAV9 enters human cells after the initial attachment to the cell surface has so far been unknown. Here, we present a systematic study concerning the internalization mechanism of CAV9 to A549 human lung carcinoma cells. The small interfering RNA (siRNA) silencing of integrin beta6 subunit inhibited virus proliferation, confirming that alphaVbeta6 mediates the CAV9 infection. However, siRNAs against integrin-linked signaling molecules, such as Src, Fyn, RhoA, phosphatidylinositol 3-kinase, and Akt1, did not reduce CAV9 proliferation, suggesting that the internalization of the virus does not involve integrin-linked signaling events. CAV9 endocytosis was independent of clathrin or caveolin-1 but was restrained by dynasore, an inhibitor of dynamin. The RNA interference silencing of beta2-microglobulin efficiently inhibited virus infection and caused CAV9 to accumulate on the cell surface. Furthermore, CAV9 infection was found to depend on Arf6 as both silencing of this molecule by siRNA and the expression of a dominant negative construct resulted in decreased virus infection. In conclusion, the internalization of CAV9 to A549 cells follows an endocytic pathway that is dependent on integrin alphaVbeta6, beta2-microglobulin, dynamin, and Arf6 but independent of clathrin and caveolin-1.

  3. Peptide-beta2-microglobulin-major histocompatibility complex expressing cells are potent antigen-presenting cells that can generate specific T cells.

    Science.gov (United States)

    Obermann, Sonja; Petrykowska, Susanne; Manns, Michael P; Korangy, Firouzeh; Greten, Tim F

    2007-09-01

    Adoptive T-cell therapy represents a promising therapeutic approach for the treatment of cancer. Successful adoptive immunotherapy depends on the ex vivo priming and expansion of antigen-specific T cells. However, the in vitro generation of adequate numbers of functional antigen-specific T cell remains a major obstacle. It is important to develop efficient and reproducible methods to generate high numbers of antigen-specific T cells for adoptive T-cell transfer. We have developed a new artificial antigen-presenting cell (aAPC) by transfection of major histocompatibility (MHC) class I negative Daudi cells with a peptide-beta2-microglobulin-MHC fusion construct (single-chain aAPC) ensuring presentation of the peptide-MHC complex of interest. Using this artificial antigen-presenting cell, we could generate up to 9.2 x 10(8) antigen-specific cytotoxic CD8(+) T cells from 10 ml blood. In vitro generated T cells lysed endogenously presented antigens. Direct comparison of the single-chain aAPC with autologous monocyte-derived dendritic cells demonstrated that these cells were equally efficient in stimulation of T cells. Finally, we were able to generate antigen-specific T cell lines from perpheral blood mononuclear cells of patients receiving cytotoxic chemotherapy. The use of single-chain aAPC represent a promising option for the generation of antigen-specific CD8(+) T cells, which could be used for adoptive T-cell therapy.

  4. Antitumor effect of beta2-microglobulin in leukemic cell-bearing mice via apoptosis-inducing activity: activation of caspase-3 and nuclear factor-kappaB.

    Science.gov (United States)

    Mori, M; Terui, Y; Tanaka, M; Tomizuka, H; Mishima, Y; Ikeda, M; Kasahara, T; Uwai, M; Ueda, M; Inoue, R; Itoh, T; Yamada, M; Hayasawa, H; Furukawa, Y; Ishizaka, Y; Ozawa, K; Hatake, K

    2001-06-01

    We have reported previously that beta2-microglobulin (beta2m) induces apoptosis in leukemic cells in vitro, and that an interaction between beta2m and HLA class I antigen induces apoptosis. Here we examined whether beta2m can induce apoptosis in leukemic cells in vivo and whether it has an antitumor effect in tumor-bearing mice. Daily administration of 50 or 250 microg of beta2m induced apoptosis and an antitumor effect on K562 leukemia cell-bearing mice in the same manner as tumor necrosis factor-alpha. In tumor tissues in beta2m-treated mice, both caspase-3 and nuclear factor-kappaB (NF-kappaB) were stained more strongly than in control mice by anti-caspase-3 and anti-NF-kappaB p65/Rel A polyclonal antibodies. We also observed the in vivo immunological effects of beta2m on lymphoid and hematopoietic organs, such as thymus, bone marrow, Peyer's patches, liver, and spleen in normal mice. Using antibodies against caspase-3 and NF-kappaB, immunohistochemical staining showed that no specific tissues were damaged or stained in normal mice. We conclude that beta2m stimulates caspase-3 and NF-kappaB pathways to induce apoptosis, making it a useful approach to a new therapy for leukemia.

  5. Modified human beta 2-microglobulin (desLys(58)) displays decreased affinity for the heavy chain of MHC class I and induces nitric oxide production and apoptosis

    DEFF Research Database (Denmark)

    Wang, M; Harhaji, L; Lamberth, K;

    2009-01-01

    Beta2-microglobulin (beta2m) is the light chain of major histocompatibility complex class I (MHC-I) molecules, and is a prerequisite for the binding of peptides to the heavy chain and their presentation to CD8+ T cells. beta2m can be modified in vivo and in vitro by proteolytic cleavage...... by complement C1 and subsequent carboxypeptidase B-like activity--processes that lead to the generation of desLys(58) beta2m (dbeta2m). This work aims to study the effect of dbeta2m on peptide binding to MHC-I, the influence of dbeta2m on the binding of beta2m to the MHC-I heavy chain and the biological...... activity of dbeta2m. Both beta2m and dbeta2m are able to support the generation of MHC-I/peptide complexes at 18 degrees C, but complexes formed in the presence of dbeta2m destabilize at 37 degrees C. Moreover, a 250 times higher concentration of dbeta2m than of beta2m is needed to displace MHC...

  6. The ESAT-6 Protein of Mycobacterium tuberculosis Interacts with Beta-2-Microglobulin (β2M) Affecting Antigen Presentation Function of Macrophage

    Science.gov (United States)

    Parveen, Nazia; Jha, Vishwanath; Valluri, Vijaya Lakshmi; Ghosh, Sudip; Mukhopadhyay, Sangita

    2014-01-01

    ESAT-6, an abundantly secreted protein of Mycobacterium tuberculosis (M. tuberculosis) is an important virulence factor, inactivation of which leads to reduced virulence of M. tuberculosis. ESAT-6 alone, or in complex with its chaperone CFP-10 (ESAT-6:CFP-10), is known to modulate host immune responses; however, the detailed mechanisms are not well understood. The structure of ESAT-6 or ESAT-6:CFP-10 complex does not suggest presence of enzymatic or DNA-binding activities. Therefore, we hypothesized that the crucial role played by ESAT-6 in the virulence of mycobacteria could be due to its interaction with some host cellular factors. Using a yeast two-hybrid screening, we identified that ESAT-6 interacts with the host protein beta-2-microglobulin (β2M), which was further confirmed by other assays, like GST pull down, co-immunoprecipitation and surface plasmon resonance. The C-terminal six amino acid residues (90–95) of ESAT-6 were found to be essential for this interaction. ESAT-6, in complex with CFP-10, also interacts with β2M. We found that ESAT-6/ESAT-6:CFP-10 can enter into the endoplasmic reticulum where it sequesters β2M to inhibit cell surface expression of MHC-I-β2M complexes, resulting in downregulation of class I-mediated antigen presentation. Interestingly, the ESAT-6:β2M complex could be detected in pleural biopsies of individuals suffering from pleural tuberculosis. Our data highlight a novel mechanism by which M. tuberculosis may undermine the host adaptive immune responses to establish a successful infection. Identification of such novel interactions may help us in designing small molecule inhibitors as well as effective vaccine design against tuberculosis. PMID:25356553

  7. The ESAT-6 protein of Mycobacterium tuberculosis interacts with beta-2-microglobulin (β2M affecting antigen presentation function of macrophage.

    Directory of Open Access Journals (Sweden)

    Gopalkrishna Sreejit

    2014-10-01

    Full Text Available ESAT-6, an abundantly secreted protein of Mycobacterium tuberculosis (M. tuberculosis is an important virulence factor, inactivation of which leads to reduced virulence of M. tuberculosis. ESAT-6 alone, or in complex with its chaperone CFP-10 (ESAT-6:CFP-10, is known to modulate host immune responses; however, the detailed mechanisms are not well understood. The structure of ESAT-6 or ESAT-6:CFP-10 complex does not suggest presence of enzymatic or DNA-binding activities. Therefore, we hypothesized that the crucial role played by ESAT-6 in the virulence of mycobacteria could be due to its interaction with some host cellular factors. Using a yeast two-hybrid screening, we identified that ESAT-6 interacts with the host protein beta-2-microglobulin (β2M, which was further confirmed by other assays, like GST pull down, co-immunoprecipitation and surface plasmon resonance. The C-terminal six amino acid residues (90-95 of ESAT-6 were found to be essential for this interaction. ESAT-6, in complex with CFP-10, also interacts with β2M. We found that ESAT-6/ESAT-6:CFP-10 can enter into the endoplasmic reticulum where it sequesters β2M to inhibit cell surface expression of MHC-I-β2M complexes, resulting in downregulation of class I-mediated antigen presentation. Interestingly, the ESAT-6:β2M complex could be detected in pleural biopsies of individuals suffering from pleural tuberculosis. Our data highlight a novel mechanism by which M. tuberculosis may undermine the host adaptive immune responses to establish a successful infection. Identification of such novel interactions may help us in designing small molecule inhibitors as well as effective vaccine design against tuberculosis.

  8. Interferon-gamma is a strong modulator of NK susceptibility and expression of beta 2-microglobulin but not of transferrin receptors of K562 cells.

    Science.gov (United States)

    Grönberg, A; Kiessling, R; Fiers, W

    1985-10-01

    The human cell line K562 was treated with human natural leukocyte interferon (IFN-alpha) and recombinant immune interferon (IFN-gamma). Cell cultures exposed to both types of IFNs displayed a reduced susceptibility to the cytotoxic activity of human PBL (NK activity). While this effect occurred preferentially at high doses of IFN-alpha, as little as 10 U/ml of IFN-gamma caused a marked decrease in susceptibility to NK-cell-mediated lysis. Using a monoclonal antibody against human beta2-microglobulin (beta2M) a low level of specific binding to K562 cells was detected. The binding increased after treatment with IFN-alpha (1.4-fold) and IFN-gamma (1.7-fold). The expression of transferrin receptors (TR) was not changed significantly. A hybrid cell line between K562 and a Burkitt's lymphoma-derived cell line displayed a similar pattern of response to IFN-alpha and IFN-gamma as did K562, when effects on NK susceptibility, beta2M expression, and TR expression were studied. The Burkitt's lymphoma line PUT showed no consistent changes in expression of beta2M and TR. These results demonstrate that IFN-gamma is highly efficient in modulating the NK susceptibility, and the expression of beta2M on K562. The presented data do not support a role for expression of TR as the only property that determines the degree of NK susceptibility, since there was no correlation between NK susceptibility and TR expression among the cell lines tested or when IFN-treated and untreated cells were compared.

  9. Serum levels of beta2-microglobulin and free light chains of immunoglobulins are associated with systemic disease activity in primary Sjogren's syndrome. Data at enrollment in the prospective ASSESS cohort.

    Directory of Open Access Journals (Sweden)

    Jacques-Eric Gottenberg

    Full Text Available OBJECTIVES: To analyze the clinical and immunological characteristics at enrollment in a large prospective cohort of patients with primary Sjögren's syndrome (pSS and to investigate the association between serum BAFF, beta2-microglobulin and free light chains of immunoglobulins and systemic disease activity at enrollment. METHODS: Three hundred and ninety five patients with pSS according to American-European Consensus Criteria were included from fifteen centers of Rheumatology and Internal Medicine in the "Assessment of Systemic Signs and Evolution of Sjögren's Syndrome" (ASSESS 5-year prospective cohort. At enrollment, serum markers were assessed as well as activity of the disease measured with the EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI. RESULTS: Patient median age was 58 (25(th-75(th: 51-67 and median disease duration was 5 (2-9 years. Median ESSDAI at enrollment was 2 (0-7 with 30.9% of patients having features of systemic involvement. Patients with elevated BAFF, beta2-microglobulin and kappa, lambda FLCS had higher ESSDAI scores at enrollment (4 [2]-[11] vs 2 [0-7], P = 0.03; 4 [1]-[11] vs 2 [0-7], P< 0.0001; 4 [2]-[10] vs 2 [0-6.6], P< 0.0001 and 4 [2-8.2] vs 2 [0-7.0], P = 0.02, respectively. In multivariate analysis, increased beta2-microglobulin, kappa and lambda FLCs were associated with a higher ESSDAI score. Median BAFF and beta2-microglobulin were higher in the 16 patients with history of lymphoma (1173.3(873.1-3665.5 vs 898.9 (715.9-1187.2 pg/ml, P = 0.01 and 2.6 (2.2-2.9 vs 2.1 (1.8-2.6 mg/l, P = 0.04, respectively. CONCLUSION: In pSS, higher levels of beta2-microglobulin and free light chains of immunoglobulins are associated with increased systemic disease activity.

  10. HLA-B27 heavy chains contribute to spontaneous inflammatory disease in B27/human beta2-microglobulin (beta2m) double transgenic mice with disrupted mouse beta2m.

    OpenAIRE

    Khare, S D; Hansen, J.; Luthra, H S; David, C S

    1996-01-01

    MHC class I allele, HLA-B27, is strongly associated with a group of human diseases called spondyloarthropathies. Some of these diseases have an onset after an enteric or genitourinary infection. In the present study, we describe spontaneous disease in HLA-B27 transgenic mice where endogenous beta2-microglobulin (beta2m) gene was replaced with transgenic human beta2m gene. These mice showed cell surface expression of HLA-B27 similar to that of human peripheral blood mononuclear cells. In addit...

  11. Binding of human beta 2-microglobulin to murine EL4 thymoma cells upregulates MHC class I heavy-chain epitopes, inhibits IL-2 secretion and induces resistance to killing by natural killer cells

    DEFF Research Database (Denmark)

    Claësson, M H; Nissen, Mogens Holst

    1994-01-01

    . EL4 cells which had bound h beta 2m decreased their rate of constitutive IL-2 secretion and became resistant to activated natural killer (NK) cell killing. The present data suggest the binding of h beta 2m to mouse T cells leads to conformational changes of MHC-I heavy chains which influence both......A variety of murine tumor cell lines was studied for its binding of exogeneously added human beta 2-microglobulin (h beta 2m). Three T lymphomas and one IL-2-dependent T-cell line (HT-1) bound substantial amounts of h beta 2m, whereas P815 mastocytoma cells, an Abelson virus-infected pre-B cell...... line (ABLS-8), X63 B-lymphoma cells and YAC cells did not bind h beta 2m. In two of the T lymphomas, EL4 and BW5147, binding of h beta 2m led to an increase in major histocompatibility complex class I (MHC-I) heavy-chain epitope expression as measured by anti-H-2K/D antibody binding and FACS analysis...

  12. Suppression of natural killer cell activity by rabbit antibody to human beta 2-microglobulin (beta 2m) is an Fc-mediated phenomenon and is not beta 2m specific.

    Science.gov (United States)

    Jones, R A; Richards, S J; Patel, D; Scott, C S

    1991-07-01

    Natural killer (NK) cell cytotoxicity constitutes an important component of the host immune defence system. The NK effector cell has been relatively well defined in terms of immunophenotypic characteristics, but in contrast to the functional T-cell receptor molecule associated with major histocompatibility complex (MHC)-restricted cytotoxic activity, the NK cell receptor has not to date been defined. However, several studies have suggested that the beta 2-microglobulin (beta 2m) molecule is functionally associated with NK cell activity. Using various heterospecific and monoclonal antibodies, this study has shown that intact rabbit IgG antibody bound either directly or indirectly to peripheral mononuclear cell (PMNC) effector populations significantly reduced their lytic activity against K562 targets. Substitution of F(ab)2 fragments for rabbit IgG antibodies, or the use of monoclonal antibodies alone, failed to reduce peripheral blood mononuclear cell (PMNC) lytic activity. Addition of non-NK cell components labelled with rabbit anti-beta 2m to purified NK-enriched effector cell populations also suppressed K562 lysis. In contrast, pre-treatment of a NK-enriched PMNC fraction with rabbit anti-beta 2m enhanced target lysis. These results strongly suggest that antibody-induced suppression of PMNC NK activity is mediated via rabbit Fc attached to co-existing non-NK cells in the mononuclear fraction, and are inconsistent with the previously suggested functional association between NK activity and membrane beta 2m.

  13. Enhanced expression in vivo of HLA-ABC antigens and beta 2-microglobulin on human lymphoid cells induced by human interferon-alpha in patients with lung cancer. Enhanced expression of class I major histocompatibility antigens prior to treatment

    DEFF Research Database (Denmark)

    Nissen, Mogens Holst; Plesner, T; Larsen, J K;

    1985-01-01

    The effect of cloned human interferon-alpha (IFN-alpha) on the expression of HLA-ABC antigens (HLA-ABC) and beta 2-microglobulin (beta 2m) on human peripheral lymphoid cells in vivo was studied by cytofluorometry using monoclonal antibodies and fluorescein-labelled rabbit anti-mouse immunoglobulin....... A significant increase in the mean fluorescence intensity of HLA-ABC (median 59%, P less than 0.001) and beta 2m (median 57%, P less than 0.001) on small lymphoid cells was observed 24 h after initiation of IFN-alpha treatment (50 X 10(6) units IFN-alpha/m2 three times a week). The enhanced expression...... of these antigens in vivo was found in 11 of 12 examined patients with primary bronchial carcinoma. A concomitant increase in serum beta 2m (median 90%, P less than 0.001) was found in all patients. In contrast the amount of cell-associated HLA-ABC and beta 2m remained unchanged (P greater than 0.1 and P greater...

  14. The relationship between concentrations of magnesium and oxidized low-density lipoprotein and Beta2-microglobulin in the serum of patients on the end-stage of renal disease.

    Science.gov (United States)

    Raikou, Vaia D; Kyriaki, Despina

    2016-05-01

    The end-stage of renal disease is associated with increased oxidative stress and oxidative modification of low-density lipoproteins (LDLs). Beta2 microglobulin (beta2M) is accumulated in the serum of dialysis patients. Magnesium (Mg) plays a protective role in the development of oxidative stress in healthy subjects. We studied the relationship between concentrations of magnesium and oxidized LDL (ox-LDL) and beta2M in the serum of patients on the end stage of renal disease. In 96 patients on on-line- predilution hemodiafiltration, beta2M and intact parathormone were measured by radioimmunoassays. High-sensitivity C-reactive protein (hsCRP) and ox-LDL were measured using ΕLISA. Serum bicarbonate levels were measured in the blood gas analyser gas machine. We performed logistic regression analysis models to investigate Mg as an important independent predictor of elevated ox-LDL and high beta2M serum concentrations, after adjustment to traditional and specific for dialysis patients' factors. We observed a positive correlation of Mg with ox-LDL (r = 0.383, P = 0.001), but the association of Mg with beta2M, hsCRP, and serum bicarbonate levels was significantly inverse (r = -0.252, P = 0.01, r = -0.292, P = 0.004, and r = -0.282, P = 0.04 respectively). The built logistic-regression analysis showed that Mg act as a significant independent factor for the elevated ox-LDL and beta2M serum concentrations adjusting to traditional and specific factors for these patients. We observed a positive relationship between magnesium and acidosis status- related ox-LDL concentrations, but the inverse association between magnesium and beta2M serum concentrations in hemodialysis patients.

  15. Calcium binding to beta-2-microglobulin at physiological pH drives the occurrence of conformational changes which cause the protein to precipitate into amorphous forms that subsequently transform into amyloid aggregates.

    Directory of Open Access Journals (Sweden)

    Sukhdeep Kumar

    Full Text Available Using spectroscopic, calorimetric and microscopic methods, we demonstrate that calcium binds to beta-2-microglobulin (β2m under physiological conditions of pH and ionic strength, in biological buffers, causing a conformational change associated with the binding of up to four calcium atoms per β2m molecule, with a marked transformation of some random coil structure into beta sheet structure, and culminating in the aggregation of the protein at physiological (serum concentrations of calcium and β2m. We draw attention to the fact that the sequence of β2m contains several potential calcium-binding motifs of the DXD and DXDXD (or DXEXD varieties. We establish (a that the microscopic aggregation seen at physiological concentrations of β2m and calcium turns into actual turbidity and visible precipitation at higher concentrations of protein and β2m, (b that this initial aggregation/precipitation leads to the formation of amorphous aggregates, (c that the formation of the amorphous aggregates can be partially reversed through the addition of the divalent ion chelating agent, EDTA, and (d that upon incubation for a few weeks, the amorphous aggregates appear to support the formation of amyloid aggregates that bind to the dye, thioflavin T (ThT, resulting in increase in the dye's fluorescence. We speculate that β2m exists in the form of microscopic aggregates in vivo and that these don't progress to form larger amyloid aggregates because protein concentrations remain low under normal conditions of kidney function and β2m degradation. However, when kidney function is compromised and especially when dialysis is performed, β2m concentrations probably transiently rise to yield large aggregates that deposit in bone joints and transform into amyloids during dialysis related amyloidosis.

  16. 纯化和标记抗人轻链β2m单克隆抗体的方法%Efficient purification and label of anti-human beta 2-microglobulin light chain monoclonal antibody

    Institute of Scientific and Technical Information of China (English)

    阮光萍; 姚翔; 庞荣清; 汪兴明; 戴莹; 潘兴华

    2011-01-01

    BACKGROUND: The inoculation of hybridoma cell strain onto mouse abdominal cavity may obtain ascites containing mass antibody. Previous method to purify monoclonal antibody in ascites is complex and difficult to operate.OBJECTIVE: To prepare, purify and label anti-human leukocyte antigen (HLA)-I class molecule light chain monoclonal antibody, and to detect the expression of tumor cell surface HLA-I class molecules. METHODS: Hybridoma cells were inoculated onto the mouse abdominal cavity. Ascites containing anti-human light chain beta2-microglobulin antibody were obtained and purified with the modified caprylic acid-ammonium sulfate method. The purified monoclonal antibody was labeled with fluorescein isothiocyanate to detect peripheral blood mononuclear cells, T2 cells expressing blank HLA-A2 molecule and K562 cells surface HLA-I class molecules. The expression of HLA-I class molecules was determined by using flow cytometry and fluorescent microscopy. RESULTS AND CONCLUSION: The purified anti-human light chain beta2-microglobulin-fluorescein isothiocyanate monoclonal antibodies accounted for 96% purity. Flow cytometry results showed that, the HLA-I class molecules were highly expressed in peripheral blood mononuclear cells surface, lowly expressed in T2 cells, and not expressed in K562 cells surface. It is a simple and convenient method to purify ascites with the modified caprylic acid-ammonium sulfate method, and according prepare anti-human light chain beta2-microglobulin-fluorescein isothiocyanate. This method is effective to distinguish the levels of HLA-I class molecules expressed in various cells.%背景:通过杂交瘤细胞株接种小鼠腹腔可获得含大量抗体的腹水,但以往纯化腹水中单克隆抗的方法较复杂,不易操作.目的:制备、纯化和标记抗人类白细胞抗原Ⅰ类分子轻链的单克隆抗体,以检测肿瘤细胞表面的人类白细胞抗原Ⅰ类分子的表达.方法:将杂交瘤细胞接种至小

  17. Serum beta2-microglobulin values among healthy Brazilians using a DPC IMMULITE® assay Valores de beta2-microglobulina em brasileiros saudáveis usando o sistema automatizado DPC IMMULITE®

    Directory of Open Access Journals (Sweden)

    Fabíola Branco Filippin

    2005-02-01

    Full Text Available PURPOSE: The present study was designed to determine the normal range of serum beta 2-microglobulin (Sb2M levels among healthy volunteers in Brazil. Levels of Sb2M are elevated in human immunodeficiency virus (HIV-infected patients and have been shown to be the best predictor of HIV infection status and of some malignant disorders, especially multiple myeloma. In order to achieve its optimal use in Brazilian clinical diagnosis, an adequate reference interval study was performed for Sb2M IMMULITE® assay, based on the fact that its reference range limits were evaluated among European populations. METHODS: Ninety-six healthy blood donors were evaluated, and Sb2M levels were measured by chemiluminescent enzyme immunoassay using the IMMULITE® automated analyzer. RESULTS: A normal range of Sb2M values, established by a nonparametric statistical method, was 1.05 to 3.9 mg/mL, with the upper limit being higher than that reported elsewhere. CONCLUSIONS: This study presented new data indicating that there is a significant difference between the current reference limits for Sb2M IMMULITE® assay and those found in Brazil, providing evidence that significant differences in range of normal values may occur among different populations, and that these new values should be considered for Brazilian individuals.OBJETIVO: O objetivo do presente estudo foi determinar valores de referência de beta2-Microglobulina sérica (Sb2M em voluntários saudáveis. Sabe-se que tal parâmetro apresenta-se elevado em pacientes infectados com o vírus da imunodeficiência humana (HIV e tem se mostrado melhor marcador da infecção por HIV e de desordens malignas, especialmente mieloma múltiplo. De forma a se obter o melhor diagnóstico clínico, um intervalo de referência adequado de Sb2M para a população brasileira foi determinado empregando-se o ensaio IMMULITE®; já que este tem como parâmetro uma faixa de referência determinada a partir de populações europ

  18. [Serum beta 2 microglobulin (beta 2M) following renal transplantation].

    Science.gov (United States)

    Pacheco-Silva, A; Nishida, S K; Silva, M S; Ramos, O L; Azjen, H; Pereira, A B

    1994-01-01

    Although there was an important improvement in graft and patient survival the last 10 years, graft rejection continues to be a major barrier to the success of renal transplantation. Identification of a laboratory test that could help to diagnose graft rejection would facilitate the management of renal transplanted patients. PURPOSE--To evaluate the utility of monitoring serum beta 2M in recently transplanted patients. METHODS--We daily determined serum beta 2M levels in 20 receptors of renal grafts (10 from living related and 10 from cadaveric donors) and compared them to their clinical and laboratory evolution. RESULTS--Eight patients who presented immediate good renal function following grafting and did not have rejection had a mean serum beta 2M of 3.7 mg/L on the 4th day post transplant. The sensitivity of the test for the diagnosis of acute rejection was 87.5%, but the specificity was only 46%. Patients who presented acute tubular necrosis (ATN) without rejection had a progressive decrease in their serum levels of beta 2M, while their serum creatinine changed as they were dialyzed. In contrast, patients with ATN and concomitance of acute rejection or CSA nephrotoxicity presented elevated beta 2M and creatinine serum levels. CONCLUSION--Daily monitoring of serum beta 2M does not improve the ability to diagnose acute rejection in patients with good renal function. However, serum beta 2M levels seemed to be useful in diagnosing acute rejection or CSA nephrotoxicity in patients with ATN.

  19. Research on the Characteristic of the Change of Serum Cystatin C and Beta2-microglobulin Concentration in Different Stages of Chronic Kidney Disease and the Correlation with Serum Creatinine%慢性肾脏病不同时期血清CysC、β2-MG的变化特点及其与Scr的相关性研究

    Institute of Scientific and Technical Information of China (English)

    孙秀丽; 陈爱珍

    2011-01-01

    目的 探讨慢性肾脏病(CKD)不同时期血清胱抑素C(cystatin C,CysC)和β2-微球蛋白(β2-MG)的变化特点及其与血肌酐(Scr)的相关性.方法 根据肾小球滤过率(GFR)将研究对象分为CKD 1、2、3、4、5 期组, 测定不同肾功能时期CysC、β2-MG、Scr、尿素氮(BUN)水平,分别与CKD1期组比较并将各期CysC、β2-MG和Scr进行相关性分析.结果 CKD2、3、4、5期组cystatin C、β2-MG与CKD1组比较有统计学意义(P<0.01).而CKD3、4、5期组SCr、BUN与CKD1组比较才有统计学意义(P<0.01).相关分析显示,385例患者血清cystatin C与SCr 之间呈正相关(r=0.85, P<0.01),β2-MG与SCr 之间呈正相关(r=0.88, P<0.01);除CKD2期组SCr与cystatin C 、β2-MG没有相关性外,其余各组SCr与cystatin C、β2-MG均有相关性.结论 慢性肾脏病患者的血清cysattniC、β2-MG在CKD2期就明显升高,提示在轻度肾功能不全患者中,CysC、β2-MG的灵敏度要明显优于SCr;CysC、β2-MG比SCr能更及时、早期反映GFR的下降.%Objective To investigate the characteristic of the change of serum cystatin C and beta2 - microglobulin concentration in different stages of chronic kidney disease and to study the correlation with serum creatinine.Methods According to glomerular filtration rate, patients were divided into five groups :1,2,3,4,5 stages of CKD groups.CysC, β2 - MG, Scr and BUN of 385 CKD patients were detected.Above mentioned chemical examination indexes of CKD 2,3,4,5 stages were compared with CKD1 respectively.CysC and β2 -MG of every CKD stage were processed by correlated analysis with Scr in accordingly CKD stages.Results The level of serum cystatin C and β2 - MG of CKD 2,3,4,5 stages had statistical significance compared to CKD1 stages( P <0.01 ),while the level of Scr and BUN of CKD 3,4,5 stages had statisticcal significance compared to CKD1 stages( P < 0.01 ).The level of serum cystatin C was positively correlated with SCr ( r = 0.85,P < 0.01 )and the

  20. 联合检测甲胎蛋白、α-岩藻糖苷酶、β2-微球蛋白及透明质酸对诊断原发性肝癌的意义%Significance of combined detection of alpha fetoprotein, alpha fucosidase, beta 2-microglobulin and hyaluronic acid in the diagnosis of primary liver cancer

    Institute of Scientific and Technical Information of China (English)

    叶宏

    2015-01-01

    目的 探讨联合检测甲胎蛋白(AFP)、α-岩藻糖苷酶(AFU)、β2-微球蛋白(β2-m)及透明质酸(HA)对诊断原发性肝癌的意义.方法 选取2012年3月~ 2014年3月在我院治疗的原发性肝癌患者60例、其他消化系癌症患者50例、肝硬化患者50例及正常健康人60例,检测所有患者血清AFP、AFU、β2-m及HA水平.结果 原发性肝癌组患者血清AFU、AFP、β2-m、HA水平及阳性检出率明显高于其他消化系癌症组、肝硬化组及正常对照组,差异有统计学意义(P<0.05).原发性肝癌组患者血清AFU、AFP、β2-m、HA四项联合检测的敏感性、诊断符合率均优于单项检测,差异有统计学意义(P<0.05).结论 联合检测AFU、AFP、β2-m、HA四种肿瘤标志物能提高早期原发性肝癌的敏感性和诊断率,为临床早期诊治提供可靠参考.%Objective To investigate the significance of combined detection of alpha fetoprotein (AFP), alpha fucosidase (AFU), beta 2-microglobulin (β2-m) and hyaluronic acid (HA) in the diagnosis of primary liver cancer. Methods 60 patients with primary liver cancer, 50 cases of other digestive system cancer, 50 patients with hepatic cirrhosis and 60 normal people from 2012 March to 2014 March in our hospital were selected,and serum AFP, AFU, β2-m and HA levels of all patients were detected.Results The levels and positive rates of serum AFP, AFU, β2-m and HA of patients with primary liver cancer were significantly higher than those of patients with other digestive system cancer, liver cirrhosis and normal people, the difference was statiscally significant (P<0.05). The sensitivity and diagnostic accordance rate of combined detection of serum AFU, AFU, β2-m and HA in patients with primary liver cancer were better than those of the single detection, the difference was statiscally significant (P<0.05). Conclusion Combined detection of AFP, AFU, β2-m and HA four tumor markers can improve the sensitivity and diagnosis rate of

  1. 脑脊液乳酸和β2微球蛋白对细菌性脑膜炎的诊断价值%The value of cerebrospinal fluid lactic acid and beta-2-microglobulin in the diagnosis of bacterial meningitis

    Institute of Scientific and Technical Information of China (English)

    赵娜; 李冬梅; 贺恒鹏; 周霞

    2014-01-01

    Objective To explore the significance of cerebrospinal fluid lactic acid (LA) and beta2-microglobulin (β2-MG) on the diagnosis of bacterial meningitis,and study their values compared with white blood cell (WBC) or protein in cerebrospinal fluid.Methods Thirty patients with bacterial meningitis were selected as bacterial meningitis group,and 30 surgical patients requiring spinal anesthesia were as control group.The level of cerebrospinal fluid LA was detected by Vitros950 automatic analyzer,and the level of cerebrospinal fluid β2-MG was detected by automatic AIA1800 enzyme immune analyzer.SPSS 13.0 and receiver operating characteristic curve (ROC curve) was used to analyze the data.Results The cerebrospinal fluid LA level in bacterial meningitis group was 1.53 (0.50) mmol/L,in control group was 1.11 (0.34) mmol/L,and there was statistical difference (P < 0.05).The cerebrospinal fluid β 2-MG level in bacterial meningitis group was 2.61 (1.00) mg/L,in control group was 0.83 (0.45) mg/L,and there was statistical difference (P < 0.01).For bacterial meningitis diagnosis,the areas under the ROC curve of cerebrospinal fluid WBC,protein,LA and β2-MG were 0.760,0.936,0.705 and 0.960.The best boundary value of LA in bacterial meningitis diagnosis was 1.78 mmol/L with a sensitivity of 68.0% and specificity of 88.9%.The best boundary value of β2-MG in bacterial meningitis diagnosis was 1.756 mg/L,with a sensitivity of 92.0% and specificity of 99.4%.Conclusions Both cerebrospinal fluid LA and β 2-MG is valuable in the diagnosis of bacterial meningitis.But for the diagnostic value,cerebrospinal fluid LA is not as good as WBC or protein in cerebrospinal fluid,but β2-MG is better than them.It has high sensitivity and specificity.%目的 探讨脑脊液(CSF)乳酸(LA)和β2微球蛋白(β2-MG)是否有助于细菌性脑膜炎(BM)的诊断,以及与CSF白细胞(WBC)、蛋白相比较,二者是否诊断价值更高.方法 选取BM患者30例作为BM组,外科手术

  2. Quantitative Analysis of Human Salivary Gland-Derived Intact Proteome Using Top-Down Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Si; Brown, Joseph N.; Tolic, Nikola; Meng, Da; Liu, Xiaowen; Zhang, Haizhen; Zhao, Rui; Moore, Ronald J.; Pevzner, Pavel A.; Smith, Richard D.; Pasa-Tolic, Ljiljana

    2014-05-31

    There are several notable challenges inherent to fully characterizing the entirety of the human saliva proteome using bottom-up approaches, including polymorphic isoforms, post-translational modifications, unique splice variants, deletions, and truncations. To address these challenges, we have developed a top-down based liquid chromatography-mass spectrometry (LC-MS) approach, which cataloged 20 major human salivary proteins with a total of 83 proteoforms, containing a broad range of post-translational modifications. Among these proteins, several previously reported disease biomarker proteins were identified at the intact protein level, such as beta-2 microglobulin (B2M). In addition, intact glycosylated proteoforms of several saliva proteins were also characterized, including intact N-glycosylated protein prolactin inducible protein (PIP) and O-glycosylated acidic protein rich protein (aPRP). These characterized proteoforms constitute an intact saliva proteoform database, which was used for quantitative comparison of intact salivary proteoforms among six healthy individuals. Human parotid (PS) and submandibular/sublingual gland (SMSL) secretion samples (2 μg of protein each) from six healthy individuals were compared using RPLC coupled with the 12T FTICR mass spectrometer. Significantly different protein and PTM patterns were resolved with high reproducibility between PS and SMSL glands. The results from this study provide further insight into the potential mechanisms of PTM pathways in oral glandular secretion, expanding our knowledge of this complex yet easily accessible fluid. Intact protein LC-MS approach presented herein can potentially be applied for rapid and accurate identification of biomarkers from only a few microliters of human glandular saliva.

  3. Quantitative Characterization of Nanostructured Materials

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Frank (Bud) Bridges, University of California-Santa Cruz

    2010-08-05

    The two-and-a-half day symposium on the "Quantitative Characterization of Nanostructured Materials" will be the first comprehensive meeting on this topic held under the auspices of a major U.S. professional society. Spring MRS Meetings provide a natural venue for this symposium as they attract a broad audience of researchers that represents a cross-section of the state-of-the-art regarding synthesis, structure-property relations, and applications of nanostructured materials. Close interactions among the experts in local structure measurements and materials researchers will help both to identify measurement needs pertinent to real-world materials problems and to familiarize the materials research community with the state-of-the-art local structure measurement techniques. We have chosen invited speakers that reflect the multidisciplinary and international nature of this topic and the need to continually nurture productive interfaces among university, government and industrial laboratories. The intent of the symposium is to provide an interdisciplinary forum for discussion and exchange of ideas on the recent progress in quantitative characterization of structural order in nanomaterials using different experimental techniques and theory. The symposium is expected to facilitate discussions on optimal approaches for determining atomic structure at the nanoscale using combined inputs from multiple measurement techniques.

  4. Quantitative flaw characterization with ultrasonic phased arrays

    Science.gov (United States)

    Engle, Brady John

    Ultrasonic nondestructive evaluation (NDE) is a critical diagnostic tool in many industries. It is used to characterize potentially dangerous flaws in critical components for aerospace, automotive, and energy applications. The use of phased array transducers allows for the extension of traditional techniques and the introduction of new methods for quantitative flaw characterization. An equivalent flaw sizing technique for use in time-of-flight diffraction setups is presented that provides an estimate of the size and orientation of isolated cracks, surface-breaking cracks, and volumetric flaws such as voids and inclusions. Experimental validation is provided for the isolated crack case. A quantitative imaging algorithm is developed that corrects for system effects and wave propagation, making the images formed directly related to the properties of the scatterer present. Simulated data is used to form images of cylindrical and spherical inclusions. The contributions of different signals to the image formation process are discussed and examples of the quantitative nature of the images are shown.

  5. Quantitative surface characterization using a Nomarski microscope

    NARCIS (Netherlands)

    Brug, H. van; Booij, S.M.; Fähnle, O.W.; Bijl, R.J.M. van der

    2000-01-01

    The use of a Nomarski microscope for the characterization of surface features will be presented. Since a Nomarski microscope measures slope values, the shape of a surface can be followed quantitatively. Besides, a Nomarski microscope can be used to analyze surface roughness in terms of rms value and

  6. The Significance of Serum beta2-Microglobulin Measurement in Various Renal Diseases

    Energy Technology Data Exchange (ETDEWEB)

    Koong, Sung Soo; Oh, Ha Yong; Han, Jin Suk; Lee, Jung Sang [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1985-03-15

    To evaluate change of serum beta{sub 2}-microglobulin concentration (sbeta{sub 2}-MG) and the usefulness of sbeta{sub 2}-MG and sbeta{sub 2}-MG/serum creatinine concentration (sCr) ratio in various renal diseases, sbeta{sub 2}-MG and sCr were measured in 25 normal controls and 90 patients of various renal diseases (16 cases of glomerulonephritis, 12 cases of acute renal failure, 8 cases of chronic renal failure, 24 cases of nephrotic syndrome, 15 cases of tubulointerstitial diseases and 15 cases of lupus nephritis) using Phadebas beta{sub 2}-Micro Test kits. The results were as follows; 1) In normal control, the mean value of sbeta{sub 2}-MG was 1.65+-0.41 mg/l and the mean value of sbeta{sub 2}-MG/sCr ratio was 0.14+-0.05. 2) In various renal diseases, the mean value of sbeta{sub 2}-MG was 6.74+-5.47 mg/l. The mean value of sbeta{sub 2}-MG/sCr ratio was 0.24+-0.11 and significantly elevated than that of normal contro1. (P<0.05). 3) The correlation between sbeta-2-MG and sCr in glomerular and tubulointerstitial disease was log sbeta{sub 2}-MG=0.90 log sCr-0.48 and its correlation coefficient was 0.78 (P<0.05). 4) In glomerular disease, the correlation between sbeta{sub 2}-MG and sCr was log sbeta{sub 2}-MG=0.89 log sCr-0.46 (r-0.76) and in tubulointerstitial disease, it was log sbeta{sub 2}-MG=0.95 1og sCr-0.59 (r-0.87). There was no significant difference between the two groups (p<0.05). 5) Among 32 cases of glomerular and tubulointerstitial disease patients, whose sCr was within normal range, 17 cases showed elevated sbeta{sub 2}-MG. The mean values of sbeta{sub 2}-MG/sCr ratio in these patients was 0.30+-0.14 and significantly elevated than that of normal control (p<0.05). 6) In 15 cases of lupus nephritis, 12 cases showed elevated sbeta{sub 2}-MG with normal sCr and 12 cases showed elevated sbeta{sub 2}-MG/sCr ratio. With above results, It was found that the sbeta{sub 2}-MG can be used as an index of glomerular filtration rate as in the case of sCr and thats sbeta{sub 2}-MG/sCr ratio can be used as a tool in early detection of slightly decreased glomerular filtration rate and in detection of the renal disease of increased beta{sub 2}-MG production.

  7. Neopterin and Beta-2 Microglobulin Relations to Immunity and Inflammatory Status in Nonischemic Dilated Cardiomyopathy Patients

    Directory of Open Access Journals (Sweden)

    Celina Wojciechowska

    2014-01-01

    Full Text Available Background. The aim of the study was to assess the relationships among serum neopterin (NPT, β2-microglobulin (β2-M levels, clinical status, and endomyocardial biopsy results of dilated cardiomyopathy patients (DCM. Methods. Serum NPT and β-2 M were determined in 172 nonischaemic DCM patients who underwent right ventricular endomyocardial biopsy and 30 healthy subjects (ELISA test. The cryostat biopsy specimens were assessed using histology, immunohistology, and immunochemistry methods (HLA ABC, HLA DR expression, CD3 + lymphocytes, and macrophages counts. Results. The strong increase of HLA ABC or HLA DR expression was detected in 27.2% patients—group A—being low in 72.8% patients—group B. Neopterin level was increased in patients in group A compared to healthy controls 8.11 (4.50–12.57 versus 4.99 (2.66–8.28 nmol/L (P<0.05. β-2 microglobulin level was higher in DCM groups A (2.60 (1.71–3.58 and B (2.52 (1.51–3.72 than in the control group 1.75 (1.28–1.96 mg/L, P<0.001. Neopterin correlated positively with the number of macrophages in biopsy specimens (P<0.05 acute phase proteins: C-reactive proteins (P<0.05; fibrinogen (P<0.01; and NYHA functional class (P<0.05 and negatively with left ventricular ejection fraction (P<0.05. Conclusions. Neopterin but not β-2 microglobulin concentration reflected immune response in biopsy specimens. Neopterin correlated with acute phase proteins and stage of heart failure and may indicate a general immune and inflammatory activation in heart failure.

  8. [Clinical usefulness of Beta2microglobulin in patients with Primary Sjögren Syndrome].

    Science.gov (United States)

    Rozzatti, M S; Fontaneto, E; Pedano, V; Racca, A; Pelosso, M; Gobbi, C; Alba, P; Demarchi, M

    2015-01-01

    Las manifestaciones extranglandulares y desórdenes linfoproliferativos son complicaciones que pueden comprometer el curso benigno del Síndrome de Sjögren Primario (SSp). Existen escasos marcadores serológicos con comprobada utilidad para predecirlas y/o diagnosticarlas. Objetivos: Evaluar la utilidad de Beta2microglobulina (β2m) en pacientes con SSp y correlacionarlos con parámetros séricos predictivos de manifestaciones extraglandulares y enfermedades linfoproliferativas (Factor Reumatoideo (FR), Inmunoglobulinas séricas (Igs), C3 y C4). Materiales y métodos: Se realizó una revisión retrospectiva de historias clínicas de pacientes que consultaron en la Unidad de Reumatología del Hospital Córdoba desde enero de 2010 a octubre 2013 y que fueron derivados a la Sección de Inmunología del Servicio de Bioquímica para la determinación de pruebas de laboratorio . Los pacientes fueron clasificados de acuerdo a los Criterios Diagnósticos de patologías autoinmunes en pacientes con diagnóstico de SSp según el Grupo Consenso Americano-Europeo, otras enfermedades autoinmunes y los controles sanos. Se estudiaron las IgG, IgA e IgM, factores del complemento C3, C4 séricos y FR por inmunoturbidimetría y β2m por ELISA. Resultados: 19 pacientes con SSp (Grupo SSp), 28 pacientes con patologías autoinmunes distintas a SSp (Grupo PAD), y 24 controles sanos (Grupo C) fueron incluidos en este estudio. Se evidenció un aumento estadísticamente significativo de β2m en el Grupo SSp respecto al Grupo C (6.19mg/dl vs 2.53mg/dl p<0.001) y respecto al Grupo PAD (6.19 vs 4.38mg/dl p<0.01). En el grupo SSp se observó aumento estadísticamente significativo de IgA (p<0.05) y G (p<0.001) y disminución de C4 (p<0.05) respecto al Grupo C. No se observó correlación entre β2m y el resto de parámetros séricos determinados. Conclusión: β2m permitió discriminar pacientes con SSp de aquellos con otras patologías autoinmunes y sujetos sanos. El aumento de β2m en pacientes con SSp podría reflejar la hiperactivación de células B y podría ser un marcador asociado con las manifestaciones extraglandulares y desórdenes linfoproliferativos.

  9. Proteolytically modified human beta 2-microglobulin augments the specific cytotoxic activity in murine mixed lymphocyte culture

    DEFF Research Database (Denmark)

    Nissen, Mogens Holst; Claësson, M H

    1987-01-01

    (M-beta 2-m) bind to murine lymphocytes expressing H-2 class I antigens; M-beta 2-m, when added at day 0 and 1 of culture in nanomolar concentrations to a one-way murine allogeneic mixed lymphocyte culture (MLC) augments the generation of specific cytotoxic T lymphocytes; M-beta 2-m increases...... the endogenous production of interleukin 2 in the MLC culture; monoclonal antibody which reacts with both the native beta 2-m and M-beta 2-m molecule blocks the augmentation of cytotoxic T lymphocyte production induced by M-beta 2-m; murine as well as human MLC responder cells can proteolytically modify native...

  10. Levels of Beta-2 Microglobulin and Cystatin C in Beta Thalassemia Major Patients

    Directory of Open Access Journals (Sweden)

    Ayse Kacar

    2014-03-01

    Full Text Available Aim: Thalassemia is accepted to be the most common genetic disease in the world. This study was performed to establish whether there was a glomerular renal damage, which was usually a less mentioned subject in patients with Beta Thalassemia Major, and to compare urea, creatinine and creatinine clearance with early indicators of kidney damage as Cystatin-C and %u03B2-2 microglobulin as on determining the glomerular damage. Material and Method: This study was prospectively performed in patients, who were regularly followed in the children hematology outpatient clinic with a diagnosis of Beta Thalassemia Major. Results: There was no statistically significant difference between urea and levels of creatinine clearance and Cystatin-C. There was a statistically negative relationship between creatinine and creatinine clearance at an advanced level as 53.7% (p: 0.002, p

  11. The Implication and Significance of Beta 2 Microglobulin: A Conservative Multifunctional Regulator

    Directory of Open Access Journals (Sweden)

    Ling Li

    2016-01-01

    Conclusions: Based on the characteristic of β2M, it or its signaling pathway has been targeted as biomedical or therapeutic tools. Moreover, β2M is highly conserved among different species, and overall structures are virtually identical, implying the versatility of β2M on applications.

  12. Serum beta-2-Microglobulin level: A parameter for early diagnosis of renal allograft rejection

    Directory of Open Access Journals (Sweden)

    Rezai A

    1994-05-01

    Full Text Available For monitoring of renal transplant function, serum B2m was evaluated in 23 recipients. According to clinical diagnosis the patients were in four groups: 1 Successful renal transplant; the mean concentration of SB2m pretransplantation was 73.1±26.1 mg/L but decreased to nearly normal level (4.43±1.17 mg/L within 24-48h and then reached to 3.1 mg/L duting 20 days after transplantation. 2 Renal dysfunction (except rejection; the maximum changes of SB2m was 1.1 mg/L/day and no significant changes of SB2m were found between this group and group 1. 3 Accelerated and acute rejection; during immunological rejection crisis, SB2m level increased and after response to antirejection therapy decreased. The daily changes of SB2m allowed to diffrentiate renal dysfunction fom rejection in 84% of cases. Moreover according to SB2m fluctuation levels, SB2m had a prognostic pattern for acute rejection due to significant differences between the level of SB2m on the day of clinical diagnosis of rejection and 4 days previously (P<0.025, and also 2 days before rejection (P<0.025, while this pattern was not found for serum creatinin and BUN.

  13. Quality control of radioimmunoassays and validation of beta-2-microglobulin radioimmunoassay

    International Nuclear Information System (INIS)

    The aim of this work was to devise a quality check procedure for radioimmunological analyses, easily applicable in all laboratories. The parameters most commonly analysed during such a test are: non-specific activity; total binding capacity; reproducibility; sensitivity; accuracy; specificity; specific activity of the labelled substance; affinity constant of the antigen towards its specific antibody. In the method proposed the calibration curve of any series of measurements is established by Rodbard's method. For the reproducibility study the use of Ekins' method, modified by Grillet and Marchand, was preferred. From the results obtained it is possible to plot the error-response relationship (ERR) and to establish the accuracy profile which gives a good idea of the sensitivity of the analysis method. For the specificity study this method matches the usual operational conditions as closely as possible. The determination is made on the following mixture: a half-volume (with respect to the usual volume) of biological liquid studied and previously analysed for cold antigen Ag0; a half-volume of one of the dilutions prepared with the substance X liable to interfere during the Ag0 determination. Any interferences between the substance X and the antigen are then plotted on a graph representing: as abscisse, the concentration of substance X; as ordinates, the difference between the measured and theoretical Ag0 concentrations. This very simple representation shows the interference threshold of each substance X; accounting for its physiopathological concentration

  14. Unfolding, aggregation, and seeded amyloid formation of lysine-58-cleaved beta(2)-microglobulin

    DEFF Research Database (Denmark)

    Heegaard, N.H.H.; Jørgensen, T.J.D.; Rozlosnik, N.;

    2005-01-01

    . Using amide hydrogen/deuterium exchange monitored by mass spectrometry, we show that Delta K58-beta(2)m has increased unfolding rates compared to wt-beta(2)m and that unfolding is highly temperature dependent. The unfolding rate is I order of magnitude faster in Delta K58-beta(2)M than in wt-beta(2)m....... After a few days at 37 degrees C, in contrast to wt-beta(2)M, Delta K-58-beta(2)M forms well-defined high molecular weight aggregates that are detected by size-exclusion chromatography. Atomic force microscopy after seeding with amyloid-beta(2)m fibrils under conditions that induce minimal fibrillation...

  15. Quantitative phosphoproteomics to characterize signaling networks

    DEFF Research Database (Denmark)

    Rigbolt, Kristoffer T G; Blagoev, Blagoy

    2012-01-01

    and quantify thousands of phosphorylations, thus providing extensive overviews of the cellular signaling networks. As a result of these developments quantitative phosphoproteomics have been applied to study processes as diverse as immunology, stem cell biology and DNA damage. Here we review the developments...... in phosphoproteomics technology that have facilitated the application of phosphoproteomics to signaling networks and introduce examples of recent system-wide applications of quantitative phosphoproteomics. Despite the great advances in phosphoproteomics technology there are still several outstanding issues and we...

  16. Towards quantitative mRNA analysis in paraffin-embedded tissues using real-time reverse transcriptase-polymerase chain reaction: a methodological study on lymph nodes from melanoma patients.

    Science.gov (United States)

    Abrahamsen, Helene Nortvig; Steiniche, Torben; Nexo, Ebba; Hamilton-Dutoit, Stephen J; Sorensen, Boe Sandahl

    2003-02-01

    Improved extraction techniques combined with sensitive real-time reverse transcriptase-polymerase chain reaction may allow detection of mRNA in formalin-fixed, paraffin-embedded (FFPE) materials, but the factors affecting mRNA quantification in clinical material using these methods have not been systematically analyzed. We designed analyses using real-time reverse transcriptase-polymerase chain reaction for quantification of MART-1, beta-actin, and beta(2)-microglobulin mRNAs. The analytical intra- and interassay imprecision (coefficient of variation) was in the range 10 to 20% for all three genes studied. Using these protocols, we studied the influence of tissue autolysis and length of formalin-fixation on mRNA detection in metastatic melanoma. Delay in freezing reduced detectable mRNA, although this was less than predicted and mostly occurred early in autolysis. MART-1, beta-actin, and beta(2)-microglobulin mRNAs were consistently detected in FFPE metastatic melanoma even after fixation for up to 3 weeks, although the total mRNA detected was markedly reduced in fixed compared with fresh tissues (up to 99%). Quantification of MART-1 was, however, possible if this was expressed relative to a housekeeping gene. The polymerase chain reaction product from FFPE tissues could be increased up to 100-fold amplifying short (tissue processing and in fixation length seem to be less important sources of imprecision than previously assumed. Our findings suggest that quantitative analysis of mRNA in archive and routine diagnostic tissues may be possible.

  17. Rheumatoid factors from patients with rheumatoid arthritis react with Des-Lys58-beta 2m, modified beta 2-microglobulin

    DEFF Research Database (Denmark)

    Williams, R C; Nissen, Mogens Holst; Malone, C C

    1993-01-01

    -cleaved beta 2m and Des-Lys58-beta 2m) appeared to parallel the previously determined beta 2m single amino acid specificities, in that RF showing strong reactivity with Lysine 58 also showed a significant diminished reactivity with the Des-Lys58-beta 2m lacking the critical lysine residue. The present...

  18. The interaction between beta 2-microglobulin (beta 2m) and purified class-I major histocompatibility (MHC) antigen

    DEFF Research Database (Denmark)

    Pedersen, L O; Hansen, A S; Olsen, A C;

    1994-01-01

    been generated recently and this paper reports on a similar assay for the interaction between beta 2m and class I. As a model system human beta 2m binding to mouse class I was used. The assay is strictly biochemical using purified reagents which interact in solution and complex formation is determined...... by size separation. It is specific and highly sensitive. The observed affinity of the interaction, KD, is close to 0.4 nM. The rate of association at 37 degrees C is very fast (the ka is around 5 x 10(4)/M/s) whereas the dissociation is slow (the kd is around 8 x 10(-6)/s); the ratio of dissociation...

  19. Pure quantitative characterization of linear groups over the binary field

    Institute of Scientific and Technical Information of China (English)

    SHI Wu-jie; WANG Lin-hong; WANG Shao-heng

    2006-01-01

    The purpose of this paper is to discuss the pure scalar characterization of the automorphism group Aut(L5(2)) and the linear group L6(2).It is proved that Aut(L5(2)) and L6(2) can be characterized quantitatively by the set of element orders.The main results are obtained by using William's work on prime graph components of finite groups and Brauer characters in trivializing the possible 2-subgroups.

  20. CMOS APS detector characterization for quantitative X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Endrizzi, Marco, E-mail: m.endrizzi@ucl.ac.uk [Dipartimento di Fisica, Università di Siena, Via Roma 56, 53100 Siena (Italy); Istituto Nazionale di Fisica Nucleare INFN, sezione di Pisa, 56127 Pisa (Italy); Oliva, Piernicola [Dipartimento di Chimica e Farmacia, Università di Sassari, via Piandanna 4, 07100 Sassari (Italy); Istituto Nazionale di Fisica Nucleare INFN, Sezione di Cagliari, 09042 Cagliari (Italy); Golosio, Bruno [Sezione di Matematica, Fisica e Ingegneria dell' Informazione, Università di Sassari, via Piandanna 4, 07100 Sassari (Italy); Istituto Nazionale di Fisica Nucleare INFN, Sezione di Cagliari, 09042 Cagliari (Italy); Delogu, Pasquale [Dipartimento di Fisica “E. Fermi”, Università di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Istituto Nazionale di Fisica Nucleare INFN, sezione di Pisa, 56127 Pisa (Italy)

    2013-03-01

    An X-ray Imaging detector based on CMOS Active Pixel Sensor and structured scintillator is characterized for quantitative X-ray imaging in the energy range 11–30 keV. Linearity, dark noise, spatial resolution and flat-field correction are the characteristics of the detector subject of investigation. The detector response, in terms of mean Analog-to-Digital Unit and noise, is modeled as a function of the energy and intensity of the X-rays. The model is directly tested using monochromatic X-ray beams and it is also indirectly validated by means of polychromatic X-ray-tube spectra. Such a characterization is suitable for quantitative X-ray imaging and the model can be used in simulation studies that take into account the actual performance of the detector.

  1. QUANTITATIVE CHARACTERIZATION OF MICROSTRUCTURE OF PURE COPPER PROCESSED BY ECAP

    Directory of Open Access Journals (Sweden)

    Ondřej Šedivý

    2013-06-01

    Full Text Available Orientation imaging microscopy (OIM allows to measure crystallic orientations at the surface of the material. Digitalized data representing the orientations are processed to recognize the grain structure and they are visualized in crystal orientation maps. Analysis of the data firstly consists in recognition of grain boundaries followed by identification of grains themselves. Knowing the grain morphology it is possible to characterize the homogeneity of the structure and estimate structural parameters related to the physical properties of the material. The paper describes methods of imaging and quantitative characterization of the grain boundary structure in metals based on data from electron backscattered diffraction (EBSD.

  2. Quantitative characterization of toughening mechanisms of rubber modified polymers

    Institute of Scientific and Technical Information of China (English)

    朱晓光; 漆宗能; 徐虎; 李刚; 蔡忠龙; C.L.Choy

    1997-01-01

    The volume changes of rubber modified polymers under creep at room temperature were successfully used to characterize the toughening mechanisms of blends with brittle polymer matrices such as high impact polystyrene.This approach cannot be applied to pseudo-ductile polymers such as polypropylene and polyamide,because they are ductile when stretched at low speed at room temperature.Based on the time-temperature equivalence princi ple,the volume change at low temperature is proposed to characterize quantitatively the toughening mechanisms of polymer blends with ductile matrices,which is illustrated by applying this approach to rubber modified polypropylene

  3. Fractal and Lacunarity Analyses: Quantitative Characterization of Hierarchical Surface Topographies.

    Science.gov (United States)

    Ling, Edwin J Y; Servio, Phillip; Kietzig, Anne-Marie

    2016-02-01

    Biomimetic hierarchical surface structures that exhibit features having multiple length scales have been used in many technological and engineering applications. Their surface topographies are most commonly analyzed using scanning electron microscopy (SEM), which only allows for qualitative visual assessments. Here we introduce fractal and lacunarity analyses as a method of characterizing the SEM images of hierarchical surface structures in a quantitative manner. Taking femtosecond laser-irradiated metals as an example, our results illustrate that, while the fractal dimension is a poor descriptor of surface complexity, lacunarity analysis can successfully quantify the spatial texture of an SEM image; this, in turn, provides a convenient means of reporting changes in surface topography with respect to changes in processing parameters. Furthermore, lacunarity plots are shown to be sensitive to the different length scales present within a hierarchical structure due to the reversal of lacunarity trends at specific magnifications where new features become resolvable. Finally, we have established a consistent method of detecting pattern sizes in an image from the oscillation of lacunarity plots. Therefore, we promote the adoption of lacunarity analysis as a powerful tool for quantitative characterization of, but not limited to, multi-scale hierarchical surface topographies. PMID:26758776

  4. Validation of Reference Genes for Normalization Gene Expression in Reverse Transcription Quantitative PCR in Human Normal Thyroid and Goiter Tissue

    Directory of Open Access Journals (Sweden)

    Raquel Weber

    2014-01-01

    Full Text Available Reverse transcription quantitative polymerase chain reaction (RT-qPCR has been recognized as the most accurate method for quantifying mRNA transcripts, but normalization of samples is a prerequisite for correct data interpretation. So, this study aimed to evaluate the most stable reference gene for RT-qPCR in human normal thyroid and goiter tissues. Beta-actin (ACTB; glyceraldehyde-3-phosphate dehydrogenase (GAPDH; succinate dehydrogenase, subunit A, flavoprotein (Fp (SDHA; hypoxanthine phosphoribosyltransferase I (HPRTI; tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein, zeta polypeptide (YWHAZ; and beta-2-microglobulin (B2M were evaluated in 14 thyroid tissue samples (7 normal and 7 goiter tissues by RT-qPCR. The mean Cq and the maximum fold change (MFC and NormFinder software were used to assess the stability of the genes. As a result, ACTB gene was more stable than GAPDH, SDHA, HPRTI, YWHAZ, and B2M. In conclusion, ACTB could be used to normalize RT-qPCR data in normal thyroid and goiter tissues.

  5. A new method for quantitatively characterizing atmospheric oxidation capacity

    Institute of Scientific and Technical Information of China (English)

    CHENG YanLi; WANG XueSong; LIU ZhaoRong; BAI YuHua; LI JinLong

    2008-01-01

    Based on atmospheric chemical kinetics, the rate constant of overall pseudo-first order oxidation re-moval of gaseous pollutants (Kpor.T) is proposed to characterize the atmospheric oxidation capacity in troposphere. Being a quantitative parameter, Kpor,T can be used to address the issues related to at-mospheric oxidation capacity. By applying this method, the regional oxidation capacity of the atmos-phere in Pearl River Delta (PRD) is numerically simulated based on CBM-Ⅳ chemical mechanism. Re-sults show the significant spatio-temporal variation of the atmospheric oxidation capacity in PRD. It is found that OH initiated oxidations, heterogeneous oxidation of SO2, and photolysis of aldehydes are the three most important oxidation processes influencing the atmospheric oxidation capacity in PRD.

  6. Characterization of early autophagy signaling by quantitative phosphoproteomics

    DEFF Research Database (Denmark)

    Rigbolt, Kristoffer Tg; Zarei, Mostafa; Sprenger, Adrian;

    2014-01-01

    Under conditions of nutrient shortage autophagy is the primary cellular mechanism ensuring availability of substrates for continuous biosynthesis. Subjecting cells to starvation or rapamycin efficiently induces autophagy by inhibiting the MTOR signaling pathway triggering increased autophagic flux....... To elucidate the regulation of early signaling events upon autophagy induction, we applied quantitative phosphoproteomics characterizing the temporal phosphorylation dynamics after starvation and rapamycin treatment. We obtained a comprehensive atlas of phosphorylation kinetics within the first 30 min upon...... induction of autophagy with both treatments affecting widely different cellular processes. The identification of dynamic phosphorylation already after 2 min demonstrates that the earliest events in autophagy signaling occur rapidly after induction. The data was subjected to extensive bioinformatics analysis...

  7. A new method for quantitatively characterizing atmospheric oxidation capacity

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Based on atmospheric chemical kinetics, the rate constant of overall pseudo-first order oxidation re-moval of gaseous pollutants (Kpor,T) is proposed to characterize the atmospheric oxidation capacity in troposphere. Being a quantitative parameter, Kpor,T can be used to address the issues related to at-mospheric oxidation capacity. By applying this method, the regional oxidation capacity of the atmos-phere in Pearl River Delta (PRD) is numerically simulated based on CBM-IV chemical mechanism. Re-sults show the significant spatio-temporal variation of the atmospheric oxidation capacity in PRD. It is found that OH initiated oxidations, heterogeneous oxidation of SO2, and photolysis of aldehydes are the three most important oxidation processes influencing the atmospheric oxidation capacity in PRD.

  8. Characterizing the anaerobic response of Chlamydomonas reinhardtii by quantitative proteomics.

    Science.gov (United States)

    Terashima, Mia; Specht, Michael; Naumann, Bianca; Hippler, Michael

    2010-07-01

    The versatile metabolism of the green alga Chlamydomonas reinhardtii is reflected in its complex response to anaerobic conditions. The anaerobic response is also remarkable in the context of renewable energy because C. reinhardtii is able to produce hydrogen under anaerobic conditions. To identify proteins involved during anaerobic acclimation as well as to localize proteins and pathways to the powerhouses of the cell, chloroplasts and mitochondria from C. reinhardtii in aerobic and anaerobic (induced by 8 h of argon bubbling) conditions were isolated and analyzed using comparative proteomics. A total of 2315 proteins were identified. Further analysis based on spectral counting clearly localized 606 of these proteins to the chloroplast, including many proteins of the fermentative metabolism. Comparative quantitative analyses were performed with the chloroplast-localized proteins using stable isotopic labeling of amino acids ([(13)C(6)]arginine/[(12)C(6)]arginine in an arginine auxotrophic strain). The quantitative data confirmed proteins previously characterized as induced at the transcript level as well as identified several new proteins of unknown function induced under anaerobic conditions. These proteins of unknown function provide new candidates for further investigation, which could bring insights for the engineering of hydrogen-producing alga strains. PMID:20190198

  9. Quantitative characterization of nanoparticle agglomeration within biological media

    Energy Technology Data Exchange (ETDEWEB)

    Hondow, Nicole, E-mail: n.hondow@leeds.ac.uk; Brydson, Rik [University of Leeds, Institute for Materials Research (United Kingdom); Wang, Peiyi [University of Leeds, Institute of Molecular and Cellular Biology (United Kingdom); Holton, Mark D.; Brown, M. Rowan; Rees, Paul; Summers, Huw D. [Swansea University, Centre for Nanohealth, College of Engineering (United Kingdom); Brown, Andy [University of Leeds, Institute for Materials Research (United Kingdom)

    2012-07-15

    Quantitative analysis of nanoparticle dispersion state within biological media is essential to understanding cellular uptake and the roles of diffusion, sedimentation, and endocytosis in determining nanoparticle dose. The dispersion of polymer-coated CdTe/ZnS quantum dots in water and cell growth medium with and without fetal bovine serum was analyzed by transmission electron microscopy (TEM) and dynamic light scattering (DLS) techniques. Characterization by TEM of samples prepared by plunge freezing the blotted solutions into liquid ethane was sensitive to the dispersion state of the quantum dots and enabled measurement of agglomerate size distributions even in the presence of serum proteins where DLS failed. In addition, TEM showed a reduced packing fraction of quantum dots per agglomerate when dispersed in biological media and serum compared to just water, highlighting the effect of interactions between the media, serum proteins, and the quantum dots. The identification of a heterogeneous distribution of quantum dots and quantum dot agglomerates in cell growth medium and serum by TEM will enable correlation with the previously reported optical metrology of in vitro cellular uptake of this quantum dot dispersion. In this paper, we present a comparative study of TEM and DLS and show that plunge-freeze TEM provides a robust assessment of nanoparticle agglomeration state.

  10. New quantitative, in-situ characterization of weathering in geomaterials.

    Science.gov (United States)

    Scrivano, Simona; Gaggero, Laura; Gisbert Aguilar, Josep; Yus Gonzalez, Adrian

    2016-04-01

    The mineralogical and microtextural analyses of weathered rocks and mortars are the main diagnostic tools to address the materials exposed under different environmental conditions in order to enucleate and mitigate the decay factors. The characterization of weathering intensity is mostly descriptive and non-quantitative (ICOMOS Glossary, 2008); the Fitzner indexes in arenites (Fitzner et al., 2002) and more recently applied to marbles (Scrivano et al., 2013) provide an operator dependent method. The current diagnostic of decay (Drdàcky & Slìzkovà, 2014) based on a scotch tape tearing off the surface was improved by a specifically adapted pocket penetrometer, and a joint gravimetric + minero-chemical analysis under SEM of ablational decay products. The steps are the following: i) Preparation of stubs for SEM with adherent conductive carbon tape (surface area 1.3 cm2) ii) Weighing of stub + tape + its plastic envelope at 0.001 g precision iii) Connecting the stub to a pocket penetrometer iv) Non invasive sampling of the incoherent dust applying a constant pressure of 2 kgf for 1 minute, and then packing away the stub without loosing grains v) Weighing of stub + tape + weathering products + their plastic envelope at 0.001 g precision vi) Recast the weight of removed material vii) Addressing the weathering products to SEM - EDS. Our quantitative peeling test was applied on a 96m long cladded wall in the Staglieno Monumental Cemetery in Genoa. The wall shows weathering gradients due to a neighbouring interred stream and to different insulation. Slabs of ophicalcite marble were tested from three different areas (5 samples were collected to the E, 5 samples at the centre, 5 samples to the W). The results highlighted capillary rise up to 2 meters height and a more weathered central area. On the whole, our protocol allows a delicate, virtually not impacting and reproducible factual sampling. Moreover, if carried out on a statistically significant population, the decay

  11. Identification of stable normalization genes for quantitative real-time PCR in porcine articular cartilage

    Directory of Open Access Journals (Sweden)

    McCulloch Ryan S

    2012-11-01

    Full Text Available Abstract Background Expression levels for genes of interest must be normalized with an appropriate reference, or housekeeping gene, to make accurate comparisons of quantitative real-time PCR results. The purpose of this study was to identify the most stable housekeeping genes in porcine articular cartilage subjected to a mechanical injury from a panel of 10 candidate genes. Results Ten candidate housekeeping genes were evaluated in three different treatment groups of mechanically impacted porcine articular cartilage. The genes evaluated were: beta actin, beta-2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, hydroxymethylbilane synthase, hypoxanthine phosphoribosyl transferase, peptidylprolyl isomerase A (cyclophilin A, ribosomal protein L4, succinate dehydrogenase flavoprotein subunit A, TATA box binding protein, and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein—zeta polypeptide. The stability of the genes was measured using geNorm, BestKeeper, and NormFinder software. The four most stable genes measured via geNorm were (most to least stable succinate dehydrogenase flavoprotein, subunit A, peptidylprolyl isomerase A, glyceraldehyde-3-phosphate dehydrogenase, beta actin; the four most stable genes measured via BestKeeper were glyceraldehyde-3-phosphate dehydrogenase, peptidylprolyl isomerase A, beta actin, succinate dehydrogenase flavoprotein, subunit A; and the four most stable genes measured via NormFinder were peptidylprolyl isomerase A, succinate dehydrogenase flavoprotein, subunit A, glyceraldehyde-3-phosphate dehydrogenase, beta actin. Conclusions BestKeeper, geNorm, and NormFinder all generated similar results for the most stable genes in porcine articular cartilage. The use of these appropriate reference genes will facilitate accurate gene expression studies of porcine articular cartilage and suggest appropriate housekeeping genes for articular cartilage studies in other species.

  12. Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments

    Science.gov (United States)

    Conners, Erin E.; West, Brooke S.; Roth, Alexis M.; Meckel-Parker, Kristen G.; Kwan, Mei-Po; Magis-Rodriguez, Carlos; Staines-Orozco, Hugo; Clapp, John D.; Brouwer, Kimberly C.

    2016-01-01

    Increasingly, ‘place’, including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC), whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs) in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1) Participatory mapping; 2) Quantitative interviews; 3) Sex work venue field observation; 4) Time-location-activity diaries; 5) In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions. PMID:27191846

  13. Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments.

    Science.gov (United States)

    Conners, Erin E; West, Brooke S; Roth, Alexis M; Meckel-Parker, Kristen G; Kwan, Mei-Po; Magis-Rodriguez, Carlos; Staines-Orozco, Hugo; Clapp, John D; Brouwer, Kimberly C

    2016-01-01

    Increasingly, 'place', including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC), whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs) in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1) Participatory mapping; 2) Quantitative interviews; 3) Sex work venue field observation; 4) Time-location-activity diaries; 5) In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions. PMID:27191846

  14. Quantitative Adhesion Characterization of Antireflective Coatings in Multijunction Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Brock, Ryan; Rewari, Raunaq; Novoa, Fernando D.; Hebert, Peter; Ermer, James; Miller, David C.; Dauskardt, Reinhold H.

    2016-08-01

    We discuss the development of a new composite dual cantilever beam (cDCB) thin-film adhesion testing method, which enables the quantitative measurement of adhesion on the thin and fragile substrates used in multijunction photovoltaics. In particular, we address the adhesion of several 2- and 3-layer antireflective coating systems on multijunction cells. By varying interface chemistry and morphology through processing, we demonstrate the marked effects on adhesion and help to develop an understanding of how high adhesion can be achieved, as adhesion values ranging from 0.5 J/m2 to 10 J/m2 were measured. Damp heat (85 degrees C/85% RH) was used to invoke degradation of interfacial adhesion. We demonstrate that even with germanium substrates that fracture relatively easily, quantitative measurements of adhesion can be made at high test yield. The cDCB test is discussed as an important new methodology, which can be broadly applied to any system that makes use of thin, brittle, or otherwise fragile substrates.

  15. Frequent lack of translation of antigen presentation-associated molecules MHC class I, CD1a and Beta(2)-microglobulin in Reed-Sternberg cells

    NARCIS (Netherlands)

    van den Berg, A.; Visser, L; Eberwine, J; Dadvand, L; Poppema, S

    2000-01-01

    Epstein-Barr virus (EBV) is present in Reed-Sternberg (RS) cells of a substantial proportion of Hodgkin's lymphoma cases. Most EBV-positive cases are also MHC class I-positive, whereas the majority of EBV-negative cases lack detectable levels of MHC class I expression. Application of the SAGE techni

  16. Normal luminal bacteria, especially Bacteroides species, mediate chronic colitis, gastritis, and arthritis in HLA-B27/human beta2 microglobulin transgenic rats.

    OpenAIRE

    Rath, H C; Herfarth, H H; Ikeda, J S; Grenther, W B; Hamm, T E; Balish, E; Taurog, J D; Hammer, R. E.; Wilson, K H; Sartor, R B

    1996-01-01

    Genetic and environmental factors are important in the pathogenesis of clinical and experimental chronic intestinal inflammation. We investigated the influence of normal luminal bacteria and several groups of selected bacterial strains on spontaneous gastrointestinal and systemic inflammation in HLA-B27 transgenic rats. Rats maintained germfree for 3-9 mo were compared with littermates conventionalized with specific pathogen-free bacteria. Subsequently, germfree transgenic rats were colonized...

  17. Dissection of a Synthesized Quantitative Trait to Characterize Transgene Interactions

    NARCIS (Netherlands)

    Nap, Jan-Peter; Conner, Anthony J.; Mlynárová, Ludmila; Stiekema, Willem J.; Jansen, Ritsert C.

    1997-01-01

    Six transgenic tobacco lines, each homozygous for the β-glucuronidase (GUS) gene at a different locus, and wild type were selfed and intercrossed to evaluate GUS activity in all possible hemizygous, homozygous and dihybrid combinations of GUS alleles. The transgenic lines are characterized by their

  18. Quantitative characterization of microstructure of pure copper processed by ECAP:

    OpenAIRE

    Ondřej Šedivý; Viktor Beneš; Petr Ponížil; Petr Král; Václav Sklenička

    2013-01-01

    Orientation imaging microscopy (OIM) allows to measure crystallic orientations at the surface of a material. Digitalized data representing the orientations are processed to recognize the grain structure and they are visualized in crystal orientation maps. Analysis of the data firstly consists in recognition of grain boundaries followed by identification of grains themselves. Knowing the grain morphology, it is possible to characterize the grain size homogeneity and estimate structural paramet...

  19. Quantitative Characterization of Phosphor Detector for Fusion Plasmas

    International Nuclear Information System (INIS)

    Experiments made to characterize phosphor screens with application as broadband radiation detectors, are described. Several radiation sources, covering the spectral range between the ultraviolet and X ray, were used. In addition, details are given of three original phosphor-screen-based detectors that were designed for use as broadband detectors in magnetically confined fusion devices. The first measurements obtained with these detectors in plasmas created in the TJ-II stellarator device are presented together with the analysis performed. (Author)

  20. Quantitative characterization of animal behavior following blast exposure

    OpenAIRE

    Rapp, Paul Ernest

    2007-01-01

    The simplest approach to quantifying animal behavior begins by identifying a list of discrete behaviors and observing the animal’s behavior at regular intervals for a specified period of time. The behavioral distribution (the fraction of observations corresponding to each behavior) is then determined. This is an incomplete characterization of behavior, and in some instances, mild injury is not reflected by statistically significant changes in the distribution even though a human observer can ...

  1. Human lymphoma-lymphoma hybrids and lymphoma-leukemia hybrids. I. Isolation, characterization, cell surface markers, and B-cell markers.

    Science.gov (United States)

    Zeuthen, J; Klein, G; Ber, R; Masucci, G; Bisballe, S; Povey, S; Terasaki, P; Ralph, P

    1982-02-01

    Four new somatic cell hybrids were obtained by fusion of various Burkitt's lymphoma (BL)-derived cell lines that had different selective markers: Raji-P3HR-1, Daudi-Raji, and a P3HR-1-P3HR-1 "autohybrid" derived from two P3HR-1 sublines. In addition, a hybrid was obtained between the Daudi (BL) line and the human leukemia cell line K562. The hybrids were extensively characterized by means of chromosome, isozyme, and HLA surface markers. The phenotypic differences between the parent cell lines allowed some conclusions with respect to the expression of latent Epstein-Barr virus (EBV) genomes, C3 and EBV receptors, and of immunoglobulin and beta 2-microglobulin-HLA expression as well as the influence of the leukemia cell (K562) genome on B-cell properties in the Daudi-K562 hybrid. B-cell and differentiated markers of these hybrids were characterized. High-level expression dominated for the marker C3 and EBV receptors, which showed a good correlation coefficient of 0.84, as was true for Fc receptors and surface immunoglobulin. The Daudi-K562 hybrid showed loss of all B-cell markers but retention of the leukemia cell markers (e.g., hemoglobin synthesis).

  2. Quantitative Characterization Guidelines of Erionite Series Minerals for Regulatory Agencies

    Science.gov (United States)

    Dogan, A.; Dogan, M.

    2013-05-01

    Erionite is a major health problem where contaminates an environment, which human population exists. Erionite - mesothelioma relationship was first observed in Turkey in 1980's and now the problem is emerging in other places in the world including Mexico. In the past, there have been in vivo or in vitro biological experiments performed using "not correctly characterized" erionite minerals. In addition, in 1997, the erionite was elevated to series status and new erionite minerals - erionite-Na, -K, -Ca - have been proposed. In 2008, erionite characterization guidelines have been proposed (Dogan and Dogan, 2008) and using these criteria, published data was re-evaluated and re-classified; and new mean chemical formula of erionite-Na, -K, -Ca was proposed. If data do not pass the E% and Mg-tests, then any reference to them in the literature is proposed to be disregarded. In some cases, different results have been reported for erionites from the same location by different authors. In these cases, if data do pass both tests but are characterized as from more than one type of erionite, then the mineral should be classified as "undifferentiated" until further clarification. Therefore, we propose (i) Erionite should be correctly characterized using proposed "positive" identification guidelines. (ii) Erionite species (whether it is -Na or -K or -Ca) should be correctly identified. (iii) There should be a close collaboration between medical community researchers and mineralogists in this field so that animal and cell experiments should be performed only with minerals that have passed "positive" identification tests. (iv) An international data bank should be established at one of the mineralogical societies and new data must be evaluated rigorously before being accepted. (v) Regulatory Agencies should ensure that the proposed guidelines for "positive" identification of erionite series minerals, both for a single fiber and a bulk mineral, are followed closely. (vi) Finally, the

  3. Quantitative microstructure characterization and elastic properties upscaling of carbonate rocks

    Science.gov (United States)

    Vialle, Stephanie; Lebedev, Maxim

    2016-04-01

    Most Rock Physics models commonly used to predict elastic properties rely on a very simplified representation of the pore and grains geometry. Initially developed for siliclastic rocks, they do not apply easily and/or with as much success, to rocks with more complicated microstructure such as carbonates, which exhibit complex relationships between geophysical attributes and rock properties, such as P-wave velocity versus porosity. Furthermore, until recently, most microstructure imaging techniques such as optical microscopy, SEM, X-ray micro-CT, etc., only give a qualitative description of the pore and grain arrangement. Nano-indentation technique is a method that gives quantitative information by mean of local (micrometer size) measurements of elastic moduli. We used this technique to obtain 300 μm * 300 μm maps of Young's moduli (around 1000 data points) of two microporous carbonates of same mineralogy but of two different microstructures. As the size of the indenter tip is much smaller than the characteristic length of the heterogeneities in microstructure, the distribution of the Young's moduli can be deconvolved into its component parts (i.e. phases). SEM imaging of the same areas than the ones mapped by nano-indentation shows correlations between type of micrite and phases of different mean Young's modulus: tight micrites exhibiting a higher Young's modulus (up to 64 GPa) than microporous micrites (as low as 9 GPa). We then investigate different ways to upscale the measurements in order to get the effective bulk and shear moduli, from simply using volume fractions of the different phases, classical Hashin-Shrikman bounds, and Hill average; to using micro-CT imaging and analysis combined with rock physics models. Though more work is still needed to render nano-indentation technique a robust method for rock physics, both on the theory behind and on the upscaling of the measurements, these results that use nano-indentation method in a statistical way are very

  4. Quantitative characterization of magnetic separators: Comparison of systems with and without integrated microfluidic mixers

    DEFF Research Database (Denmark)

    Lund-Olesen, Torsten; Bruus, Henrik; Hansen, Mikkel Fougt

    2006-01-01

    We present two new types of microfluidic passive magnetic bead separator systems as well as methods for performing quantitative characterizations of them. Both systems consist of a microfluidic channel with long rectangular magnetic elements of permalloy that are placed by the sides of the channe...

  5. Evaluation of reference genes for quantitative real-time RT-PCR analysis of gene expression in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Yang, Chang Geng; Wang, Xian Li; Tian, Juan; Liu, Wei; Wu, Fan; Jiang, Ming; Wen, Hua

    2013-09-15

    Quantitative real-time reverse-transcriptase polymerase chain reaction (RT-qPCR) has been used frequently to study gene expression related to fish immunology. In such studies, a stable reference gene should be selected to correct the expression of the target gene. In this study, seven candidate reference genes (glyceraldehyde-3-phosphate dehydrogenase (GADPH), ubiquitin-conjugating enzyme (UBCE), 18S ribosomal RNA (18S rRNA), beta-2-microglobulin (B2M), elongation factor 1 alpha (EF1A), tubulin alpha chain-like (TUBA) and beta actin (ACTB)), were selected to analyze their stability and normalization in seven tissues (liver, spleen, kidney, brain, heart, muscle and intestine) of Nile tilapia (Oreochromis niloticus) challenged with Streptococcus agalactiae or Streptococcus iniae, respectively. The results showed that all the candidate reference genes exhibited tissue-dependent transcriptional variations. With PBS injection as a control, UBCE was the most stable and suitable single reference gene in the intestine, liver, brain, kidney, and spleen after S. iniae infection, and in the liver, kidney, and spleen after S. agalactiae infection. EF1A was the most suitable in heart and muscle after S. iniae or S. agalactiae infection. GADPH was the most suitable gene in intestine and brain after S. agalactiae infection. In normal conditions, UBCE and 18S rRNA were the most stably expressed genes across the various tissues. These results showed that for RT-qPCR analysis of tilapia, selecting two or more reference genes may be more suitable for cross-tissue analysis of gene expression.

  6. Selection of suitable housekeeping genes for real-time quantitative PCR in CD4(+ lymphocytes from asthmatics with or without depression.

    Directory of Open Access Journals (Sweden)

    Ting Wang

    Full Text Available OBJECTIVE: No optimal housekeeping genes (HKGs have been identified for CD4(+ T cells from non-depressive asthmatic and depressive asthmatic adults for normalizing quantitative real-time PCR (qPCR assays. The aim of present study was to select appropriate HKGs for gene expression analysis in purified CD4(+ T cells from these asthmatics. METHODS: Three groups of subjects (Non-depressive asthmatic, NDA, n = 10, Depressive asthmatic, DA, n = 11, and Healthy control, HC, n = 10 respectively were studied. qPCR for 9 potential HKGs, namely RNA, 28S ribosomal 1 (RN28S1, ribosomal protein, large, P0 (RPLP0, actin, beta (ACTB, cyclophilin A (PPIA, glyceraldehyde-3-phosphate dehydrogenase (GAPDH, phosphoglycerate kinase 1 (PGK1, beta-2-microglobulin (B2M, glucuronidase, beta (GUSB and ribosomal protein L13a (RPL13A, was performed. Then the data were analyzed with three different applications namely BestKeeper, geNorm, and NormFinder. RESULTS: The analysis of gene expression data identified B2M and RPLP0 as the most stable reference genes and showed that the level of PPIA was significantly different among subjects of three groups when the two best HKGs identified were applied. Post-hoc analysis by Student-Newman-Keuls correction shows that depressive asthmatics and non-depressive asthmatics exhibited lower expression level of PPIA than healthy controls (p<0.05. CONCLUSIONS: B2M and RPLP0 were identified as the most optimal HKGs in gene expression studies involving human blood CD4(+ T cells derived from normal, depressive asthmatics and non-depressive asthmatics. The suitability of using the PPIA gene as the HKG for such studies was questioned due to its low expression in asthmatics.

  7. Quantitative data analysis methods for 3D microstructure characterization of Solid Oxide Cells

    DEFF Research Database (Denmark)

    Jørgensen, Peter Stanley

    the microstructure. The methods are exemplied by the analysis of Ni-YSZ and LSC-CGO electrode samples. Automatic methods for preprocessing the raw 3D image data are developed. The preprocessing steps correct for errors introduced by the image acquisition by the focused ion beam serial sectioning. Alignment...... for gaining further fundamental understanding of how microstructure affects performance. In this work, methods for automatic 3D characterization of microstructure are studied: from the acquisition of 3D image data by focused ion beam tomography to the extraction of quantitative measures that characterize...... of the individual image slices is performed by automatic detection of ducial marks. Uneven illumination is corrected by tting hypersurfaces to the spatial intensity variation in the 3D image data. Routine use of quantitative three dimensional analysis of microstructure is generally restricted by the time consuming...

  8. Pattern recognition characterizations of micromechanical and morphological materials states via analytical quantitative ultrasonics

    Science.gov (United States)

    Williams, J. H., Jr.; Lee, S. S.

    1986-01-01

    One potential approach to the quantitative acquisition of discriminatory information that can isolate a single structural state is pattern recognition. The pattern recognition characterizations of micromechanical and morphological materials states via analytical quantiative ultrasonics are outlined. The concepts, terminology, and techniques of statistical pattern recognition are reviewed. Feature extraction and classification and states of the structure can be determined via a program of ultrasonic data generation.

  9. Quantitative Ultrasound Spectroscopic Imaging for Characterization of Disease Extent in Prostate Cancer Patients

    Directory of Open Access Journals (Sweden)

    Ali Sadeghi-Naini

    2015-02-01

    Full Text Available Three-dimensional quantitative ultrasound spectroscopic imaging of prostate was investigated clinically for the noninvasive detection and extent characterization of disease in cancer patients and compared to whole-mount, whole-gland histopathology of radical prostatectomy specimens. Fifteen patients with prostate cancer underwent a volumetric transrectal ultrasound scan before radical prostatectomy. Conventional-frequency (~5 MHz ultrasound images and radiofrequency data were collected from patients. Normalized power spectra were used as the basis of quantitative ultrasound spectroscopy. Specifically, color-coded parametric maps of 0-MHz intercept, midband fit, and spectral slope were computed and used to characterize prostate tissue in ultrasound images. Areas of cancer were identified in whole-mount histopathology specimens, and disease extent was correlated to that estimated from quantitative ultrasound parametric images. Midband fit and 0-MHz intercept parameters were found to be best associated with the presence of disease as located on histopathology whole-mount sections. Obtained results indicated a correlation between disease extent estimated noninvasively based on midband fit parametric images and that identified histopathologically on prostatectomy specimens, with an r2 value of 0.71 (P < .0001. The 0-MHz intercept parameter demonstrated a lower level of correlation with histopathology. Spectral slope parametric maps offered no discrimination of disease. Multiple regression analysis produced a hybrid disease characterization model (r2 = 0.764, P < .05, implying that the midband fit biomarker had the greatest correlation with the histopathologic extent of disease. This work demonstrates that quantitative ultrasound spectroscopic imaging can be used for detecting prostate cancer and characterizing disease extent noninvasively, with corresponding gross three-dimensional histopathologic correlation.

  10. Quantitative ultrasound spectroscopic imaging for characterization of disease extent in prostate cancer patients.

    Science.gov (United States)

    Sadeghi-Naini, Ali; Sofroni, Ervis; Papanicolau, Naum; Falou, Omar; Sugar, Linda; Morton, Gerard; Yaffe, Martin J; Nam, Robert; Sadeghian, Alireza; Kolios, Michael C; Chung, Hans T; Czarnota, Gregory J

    2015-02-01

    Three-dimensional quantitative ultrasound spectroscopic imaging of prostate was investigated clinically for the noninvasive detection and extent characterization of disease in cancer patients and compared to whole-mount, whole-gland histopathology of radical prostatectomy specimens. Fifteen patients with prostate cancer underwent a volumetric transrectal ultrasound scan before radical prostatectomy. Conventional-frequency (~5MHz) ultrasound images and radiofrequency data were collected from patients. Normalized power spectra were used as the basis of quantitative ultrasound spectroscopy. Specifically, color-coded parametric maps of 0-MHz intercept, midband fit, and spectral slope were computed and used to characterize prostate tissue in ultrasound images. Areas of cancer were identified in whole-mount histopathology specimens, and disease extent was correlated to that estimated from quantitative ultrasound parametric images. Midband fit and 0-MHz intercept parameters were found to be best associated with the presence of disease as located on histopathology whole-mount sections. Obtained results indicated a correlation between disease extent estimated noninvasively based on midband fit parametric images and that identified histopathologically on prostatectomy specimens, with an r(2) value of 0.71 (P<.0001). The 0-MHz intercept parameter demonstrated a lower level of correlation with histopathology. Spectral slope parametric maps offered no discrimination of disease. Multiple regression analysis produced a hybrid disease characterization model (r(2)=0.764, P<.05), implying that the midband fit biomarker had the greatest correlation with the histopathologic extent of disease. This work demonstrates that quantitative ultrasound spectroscopic imaging can be used for detecting prostate cancer and characterizing disease extent noninvasively, with corresponding gross three-dimensional histopathologic correlation.

  11. Quantitative Ultrasound Spectroscopic Imaging for Characterization of Disease Extent in Prostate Cancer Patients1

    Science.gov (United States)

    Sadeghi-Naini, Ali; Sofroni, Ervis; Papanicolau, Naum; Falou, Omar; Sugar, Linda; Morton, Gerard; Yaffe, Martin J.; Nam, Robert; Sadeghian, Alireza; Kolios, Michael C.; Chung, Hans T.; Czarnota, Gregory J.

    2015-01-01

    Three-dimensional quantitative ultrasound spectroscopic imaging of prostate was investigated clinically for the noninvasive detection and extent characterization of disease in cancer patients and compared to whole-mount, whole-gland histopathology of radical prostatectomy specimens. Fifteen patients with prostate cancer underwent a volumetric transrectal ultrasound scan before radical prostatectomy. Conventional-frequency (~ 5 MHz) ultrasound images and radiofrequency data were collected from patients. Normalized power spectra were used as the basis of quantitative ultrasound spectroscopy. Specifically, color-coded parametric maps of 0-MHz intercept, midband fit, and spectral slope were computed and used to characterize prostate tissue in ultrasound images. Areas of cancer were identified in whole-mount histopathology specimens, and disease extent was correlated to that estimated from quantitative ultrasound parametric images. Midband fit and 0-MHz intercept parameters were found to be best associated with the presence of disease as located on histopathology whole-mount sections. Obtained results indicated a correlation between disease extent estimated noninvasively based on midband fit parametric images and that identified histopathologically on prostatectomy specimens, with an r2 value of 0.71 (P < .0001). The 0-MHz intercept parameter demonstrated a lower level of correlation with histopathology. Spectral slope parametric maps offered no discrimination of disease. Multiple regression analysis produced a hybrid disease characterization model (r2 = 0.764, P < .05), implying that the midband fit biomarker had the greatest correlation with the histopathologic extent of disease. This work demonstrates that quantitative ultrasound spectroscopic imaging can be used for detecting prostate cancer and characterizing disease extent noninvasively, with corresponding gross three-dimensional histopathologic correlation. PMID:25749174

  12. Quantitative analysis of estimated scattering coefficient and phase retardation for ovarian tissue characterization

    OpenAIRE

    Yang, Yi; Wang, Tianheng; Wang, Xiaohong; Sanders, Melinda; Brewer, Molly; Zhu, Quing

    2012-01-01

    In this report, optical scattering coefficient and phase retardation quantitatively estimated from polarization-sensitive OCT (PSOCT) were used for ovarian tissue characterization. A total of 33 ex vivo ovaries (normal: n = 26, malignant: n = 7) obtained from 18 patients were investigated. A specificity of 100% and a sensitivity of 86% were achieved by using estimated scattering coefficient alone; and a specificity of 100% and a sensitivity of 43% were obtained by using phase retardation alon...

  13. Quantitative characterization of processing-microstructure-properties relationships in pressure die-cast magnesium alloys

    Science.gov (United States)

    Lee, Soon Gi

    The central goal of this research is to quantitatively characterize the relationships between processing, microstructure, and mechanical properties of important high-pressure die-cast (HPDC) Mg-alloys. For this purpose, a new digital image processing technique for automatic detection and segmentation of gas and shrinkage pores in the cast microstructure is developed and it is applied to quantitatively characterize the effects of HPDC process parameters on the size distribution and spatial arrangement of porosity. To get better insights into detailed geometry and distribution of porosity and other microstructural features, an efficient and unbiased montage based serial sectioning technique is applied for reconstruction of three-dimensional microstructures. The quantitative microstructural data have been correlated to the HPDC process parameters and the mechanical properties. The analysis has led to hypothesis of formation of new type of shrinkage porosity called, "gas induced shrinkage porosity" that has been substantiated via simple heat transfer simulations. The presence of inverse surface macrosegregation has been also shown for the first time in the HPDC Mg-alloys. An image analysis based technique has been proposed for simulations of realistic virtual microstructures that have realistic complex pore morphologies. These virtual microstructures can be implemented in the object oriented finite elements framework to model the variability in the fracture sensitive mechanical properties of the HPDC alloys.

  14. Qualitative and Quantitative Assays for Detection and Characterization of Protein Antimicrobials.

    Science.gov (United States)

    Farris, M Heath; Ford, Kara A; Doyle, Richard C

    2016-01-01

    Initial evaluations of large microbial libraries for potential producers of novel antimicrobial proteins require both qualitative and quantitative methods to screen for target enzymes prior to investing greater research effort and resources. The goal of this protocol is to demonstrate two complementary assays for conducting these initial evaluations. The microslide diffusion assay provides an initial or simple detection screen to enable the qualitative and rapid assessment of proteolytic activity against an array of both viable and heat-killed bacterial target substrates. As a counterpart, the increased sensitivity and reproducibility of the dye-release assay provides a quantitative platform for evaluating and comparing environmental influences affecting the hydrolytic activity of protein antimicrobials. The ability to label specific heat-killed cell culture substrates with Remazol brilliant blue R dye expands this capability to tailor the dye-release assay to characterize enzymatic activity of interest.

  15. Quantitative characterization of the filiform mechanosensory hair array on the cricket cercus.

    Directory of Open Access Journals (Sweden)

    John P Miller

    Full Text Available BACKGROUND: Crickets and other orthopteran insects sense air currents with a pair of abdominal appendages resembling antennae, called cerci. Each cercus in the common house cricket Acheta domesticus is approximately 1 cm long, and is covered with 500 to 750 filiform mechanosensory hairs. The distribution of the hairs on the cerci, as well as the global patterns of their movement vectors, have been characterized semi-quantitatively in studies over the last 40 years, and have been shown to be very stereotypical across different animals in this species. Although the cercal sensory system has been the focus of many studies in the areas of neuroethology, development, biomechanics, sensory function and neural coding, there has not yet been a quantitative study of the functional morphology of the receptor array of this important model system. METHODOLOGY/PRINCIPAL FINDINGS: We present a quantitative characterization of the structural characteristics and functional morphology of the cercal filiform hair array. We demonstrate that the excitatory direction along each hair's movement plane can be identified by features of its socket that are visible at the light-microscopic level, and that the length of the hair associated with each socket can also be estimated accurately from a structural parameter of the socket. We characterize the length and directionality of all hairs on the basal half of a sample of three cerci, and present statistical analyses of the distributions. CONCLUSIONS/SIGNIFICANCE: The inter-animal variation of several global organizational features is low, consistent with constraints imposed by functional effectiveness and/or developmental processes. Contrary to previous reports, however, we show that the filiform hairs are not re-identifiable in the strict sense.

  16. QUANTITATIVE CHARACTERIZATION OF STRESS-STRAIN HYSTERESIS LOOPS OF Cu-Zn-Al SHAPE MEMORY ALLOY

    Institute of Scientific and Technical Information of China (English)

    Y.F. Guo; Y.Z. Huo; G.T. Zeng; X.T. Zu

    2001-01-01

    A six-parameter mathematical model was introduced to simulate the stress-strain hysteresis and the inner hysteresis of polycrystalline shape memory alloys (SMAs). By comparing with experiments of Cu-Zn-Al SMA, it was shown that the model could be used to calculate the stress-strain relations with rather good accuracy. Moreover,it was found that the six parameters introduced in this paper represented the characteristics of the stress-strain hysteresis of polycrystalline SMA and can be used to characterize the hysteresis quantitatively.

  17. Quantitative atom probe tomography characterization of microstructures in a proton irradiated 304 stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yimeng [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109-2136 (United States); Chou, Peter H. [Electric Power Research Institute, Palo Alto, CA 94304 (United States); Marquis, Emmanuelle A., E-mail: emarq@umich.edu [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109-2136 (United States)

    2014-08-01

    Abstract: Irradiation of 304 stainless steels induces complex microstructural changes such as solute clustering, precipitation, and segregation to dislocations, which have been best characterized by atom probe tomography. However, reliably and reproducibly quantifying these localized chemical changes can be challenging. To this end, an approach for quantitative cluster and dislocation analysis of the atom probe tomography data is proposed. The method is applied to the quantification of Cu clusters, Ni–Si rich clusters and Si, Ni and P segregation to dislocations that are observed in a 304 stainless steel that was proton irradiated at 360 °C to 10 dpa.

  18. Quantitative Acoustic Emission Fatigue Crack Characterization in Structural Steel and Weld

    Directory of Open Access Journals (Sweden)

    Adutwum Marfo

    2013-01-01

    Full Text Available The fatigue crack growth characteristics of structural steel and weld connections are analyzed using quantitative acoustic emission (AE technique. This was experimentally investigated by three-point bending testing of specimens under low cycle constant amplitude loading using the wavelet packet analysis. The crack growth sequence, that is, initiation, crack propagation, and fracture, is extracted from their corresponding frequency feature bands, respectively. The results obtained proved to be superior to qualitative AE analysis and the traditional linear elastic fracture mechanics for fatigue crack characterization in structural steel and welds.

  19. Satellite perspective of aerosol intercontinental transport: From qualitative tracking to quantitative characterization

    Science.gov (United States)

    Yu, Hongbin; Remer, Lorraine A.; Kahn, Ralph A.; Chin, Mian; Zhang, Yan

    2013-04-01

    Evidence of aerosol intercontinental transport (ICT) is both widespread and compelling. Model simulations suggest that ICT could significantly affect regional air quality and climate, but the broad inter-model spread of results underscores a need of constraining model simulations with measurements. Satellites have inherent advantages over in situ measurements to characterize aerosol ICT, because of their spatial and temporal coverage. Significant progress in satellite remote sensing of aerosol properties during the Earth Observing System (EOS) era offers the opportunity to increase quantitative characterization and estimates of aerosol ICT beyond the capability of pre-EOS era satellites that could only qualitatively track aerosol plumes. EOS satellites also observe emission strengths and injection heights of some aerosols, aerosol precursors, and aerosol-related gases, which can help characterize aerosol ICT. We review how the current generation of satellite measurements have been used to (1) characterize the evolution of aerosol plumes (e.g., both horizontal and vertical transport, and properties) on an episodic basis, (2) understand the seasonal and inter-annual variations of aerosol ICT and their control factors, (3) estimate the export and import fluxes of aerosols, and (4) evaluate and constrain model simulations. Substantial effort is needed to further explore an integrated approach using measurements from on-orbit satellites (e.g., A-Train synergy) for observational characterization and model constraint of aerosol intercontinental transport and to develop advanced sensors for future missions.

  20. Satellite Perspective of Aerosol Intercontinental Transport: From Qualitative Tracking to Quantitative Characterization

    Science.gov (United States)

    Yu, Hongbin; Remer, Lorraine A.; Kahn, Ralph A.; Chin, Mian; Zhang, Yan

    2012-01-01

    Evidence of aerosol intercontinental transport (ICT) is both widespread and compelling. Model simulations suggest that ICT could significantly affect regional air quality and climate, but the broad inter-model spread of results underscores a need of constraining model simulations with measurements. Satellites have inherent advantages over in situ measurements to characterize aerosol ICT, because of their spatial and temporal coverage. Significant progress in satellite remote sensing of aerosol properties during the Earth Observing System (EOS) era offers opportunity to increase quantitative characterization and estimates of aerosol ICT, beyond the capability of pre-EOS era satellites that could only qualitatively track aerosol plumes. EOS satellites also observe emission strengths and injection heights of some aerosols, aerosol precursors, and aerosol-related gases, which can help characterize aerosol ICT. After an overview of these advances, we review how the current generation of satellite measurements have been used to (1) characterize the evolution of aerosol plumes (e.g., both horizontal and vertical transport, and properties) on an episodic basis, (2) understand the seasonal and inter-annual variations of aerosol ICT and their control factors, (3) estimate the export and import fluxes of aerosols, and (4) evaluate and constrain model simulations. Substantial effort is needed to further explore an integrated approach using measurements from on-orbit satellites (e.g., A-Train synergy) for observational characterization and model constraint of aerosol intercontinental transport and to develop advanced sensors for future missions.

  1. Thermographic detection and quantitative characterization of corrosion by application of thermal line source

    Science.gov (United States)

    Cramer, K. Elliott; Winfree, William P.; Reid, Dan; Johnson, Jane

    1999-02-01

    Wall thinning in utility boiler waterwall tubing is a significant inspection concern for boiler operators. Historically, conventional ultrasonics has been used for inspection of these tubes. This technique has proved to be very labor intensive and slow. This has resulted in a `spot check' approach to inspections, making thickness measurements over a relatively small percentage of the total boiler wall area. NASA Langley Research Center has developed a thermal NDE technique designed to image and quantitatively characterize the amount of material thinning present in steel tubing. The technique involves the movement of a thermal line source across the outer surface of the tubing followed by an infrared imager at a fixed distance behind the line source. Quantitative images of the material loss due to corrosion are reconstructed from measurements of the induced surface temperature variations. This paper will present a discussion of the development of the thermal imaging system as well as the techniques used to reconstruct images of flaws. The application of the thermal line source, coupled with this analysis technique, represents a significant improvement in the inspection speed for large structures such as boiler waterwalls while still providing high-resolution thickness measurements. A theoretical basis for the technique will be presented thus demonstrating the quantitative nature of the technique. Further, results of laboratory experiments on flat panel specimens with fabricated material loss regions will be presented to demonstrate the capabilities of the technique. Additionally, the results of applying this technology to actual waterwall tubing samples will be presented.

  2. Activated sludge characterization through microscopy: A review on quantitative image analysis and chemometric techniques

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, Daniela P. [IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Amaral, A. Luís [IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Instituto Politécnico de Coimbra, ISEC, DEQB, Rua Pedro Nunes, Quinta da Nora, 3030-199 Coimbra (Portugal); Ferreira, Eugénio C., E-mail: ecferreira@deb.uminho.pt [IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal)

    2013-11-13

    Graphical abstract: -- Highlights: •Quantitative image analysis shows potential to monitor activated sludge systems. •Staining techniques increase the potential for detection of operational problems. •Chemometrics combined with quantitative image analysis is valuable for process monitoring. -- Abstract: In wastewater treatment processes, and particularly in activated sludge systems, efficiency is quite dependent on the operating conditions, and a number of problems may arise due to sludge structure and proliferation of specific microorganisms. In fact, bacterial communities and protozoa identification by microscopy inspection is already routinely employed in a considerable number of cases. Furthermore, quantitative image analysis techniques have been increasingly used throughout the years for the assessment of aggregates and filamentous bacteria properties. These procedures are able to provide an ever growing amount of data for wastewater treatment processes in which chemometric techniques can be a valuable tool. However, the determination of microbial communities’ properties remains a current challenge in spite of the great diversity of microscopy techniques applied. In this review, activated sludge characterization is discussed highlighting the aggregates structure and filamentous bacteria determination by image analysis on bright-field, phase-contrast, and fluorescence microscopy. An in-depth analysis is performed to summarize the many new findings that have been obtained, and future developments for these biological processes are further discussed.

  3. Activated sludge characterization through microscopy: A review on quantitative image analysis and chemometric techniques

    International Nuclear Information System (INIS)

    Graphical abstract: -- Highlights: •Quantitative image analysis shows potential to monitor activated sludge systems. •Staining techniques increase the potential for detection of operational problems. •Chemometrics combined with quantitative image analysis is valuable for process monitoring. -- Abstract: In wastewater treatment processes, and particularly in activated sludge systems, efficiency is quite dependent on the operating conditions, and a number of problems may arise due to sludge structure and proliferation of specific microorganisms. In fact, bacterial communities and protozoa identification by microscopy inspection is already routinely employed in a considerable number of cases. Furthermore, quantitative image analysis techniques have been increasingly used throughout the years for the assessment of aggregates and filamentous bacteria properties. These procedures are able to provide an ever growing amount of data for wastewater treatment processes in which chemometric techniques can be a valuable tool. However, the determination of microbial communities’ properties remains a current challenge in spite of the great diversity of microscopy techniques applied. In this review, activated sludge characterization is discussed highlighting the aggregates structure and filamentous bacteria determination by image analysis on bright-field, phase-contrast, and fluorescence microscopy. An in-depth analysis is performed to summarize the many new findings that have been obtained, and future developments for these biological processes are further discussed

  4. Quantitative impact characterization of aeronautical CFRP materials with non-destructive testing methods

    Energy Technology Data Exchange (ETDEWEB)

    Kiefel, Denis, E-mail: Denis.Kiefel@airbus.com, E-mail: Rainer.Stoessel@airbus.com; Stoessel, Rainer, E-mail: Denis.Kiefel@airbus.com, E-mail: Rainer.Stoessel@airbus.com [Airbus Group Innovations, Munich (Germany); Grosse, Christian, E-mail: Grosse@tum.de [Technical University Munich (Germany)

    2015-03-31

    In recent years, an increasing number of safety-relevant structures are designed and manufactured from carbon fiber reinforced polymers (CFRP) in order to reduce weight of airplanes by taking the advantage of their specific strength into account. Non-destructive testing (NDT) methods for quantitative defect analysis of damages are liquid- or air-coupled ultrasonic testing (UT), phased array ultrasonic techniques, and active thermography (IR). The advantage of these testing methods is the applicability on large areas. However, their quantitative information is often limited on impact localization and size. In addition to these techniques, Airbus Group Innovations operates a micro x-ray computed tomography (μ-XCT) system, which was developed for CFRP characterization. It is an open system which allows different kinds of acquisition, reconstruction, and data evaluation. One main advantage of this μ-XCT system is its high resolution with 3-dimensional analysis and visualization opportunities, which enables to gain important quantitative information for composite part design and stress analysis. Within this study, different NDT methods will be compared at CFRP samples with specified artificial impact damages. The results can be used to select the most suitable NDT-method for specific application cases. Furthermore, novel evaluation and visualization methods for impact analyzes are developed and will be presented.

  5. Quantitative ultrasound characterization of locally advanced breast cancer by estimation of its scatterer properties

    Energy Technology Data Exchange (ETDEWEB)

    Tadayyon, Hadi [Physical Sciences, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario M5G 2M9 (Canada); Sadeghi-Naini, Ali; Czarnota, Gregory, E-mail: Gregory.Czarnota@sunnybrook.ca [Physical Sciences, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario M5G 2M9 (Canada); Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Radiation Oncology, Faculty of Medicine, University of Toronto, Toronto, Ontario M5T 1P5 (Canada); Wirtzfeld, Lauren [Department of Physics, Ryerson University, Toronto, Ontario M5B 2K3 (Canada); Wright, Frances C. [Division of Surgical Oncology, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada)

    2014-01-15

    Purpose: Tumor grading is an important part of breast cancer diagnosis and currently requires biopsy as its standard. Here, the authors investigate quantitative ultrasound parameters in locally advanced breast cancers that can potentially separate tumors from normal breast tissue and differentiate tumor grades. Methods: Ultrasound images and radiofrequency data from 42 locally advanced breast cancer patients were acquired and analyzed. Parameters related to the linear regression of the power spectrum—midband fit, slope, and 0-MHz-intercept—were determined from breast tumors and normal breast tissues. Mean scatterer spacing was estimated from the spectral autocorrelation, and the effective scatterer diameter and effective acoustic concentration were estimated from the Gaussian form factor. Parametric maps of each quantitative ultrasound parameter were constructed from the gated radiofrequency segments in tumor and normal tissue regions of interest. In addition to the mean values of the parametric maps, higher order statistical features, computed from gray-level co-occurrence matrices were also determined and used for characterization. Finally, linear and quadratic discriminant analyses were performed using combinations of quantitative ultrasound parameters to classify breast tissues. Results: Quantitative ultrasound parameters were found to be statistically different between tumor and normal tissue (p < 0.05). The combination of effective acoustic concentration and mean scatterer spacing could separate tumor from normal tissue with 82% accuracy, while the addition of effective scatterer diameter to the combination did not provide significant improvement (83% accuracy). Furthermore, the two advanced parameters, including effective scatterer diameter and mean scatterer spacing, were found to be statistically differentiating among grade I, II, and III tumors (p = 0.014 for scatterer spacing, p = 0.035 for effective scatterer diameter). The separation of the tumor

  6. Quantitative ultrasound characterization of locally advanced breast cancer by estimation of its scatterer properties

    International Nuclear Information System (INIS)

    Purpose: Tumor grading is an important part of breast cancer diagnosis and currently requires biopsy as its standard. Here, the authors investigate quantitative ultrasound parameters in locally advanced breast cancers that can potentially separate tumors from normal breast tissue and differentiate tumor grades. Methods: Ultrasound images and radiofrequency data from 42 locally advanced breast cancer patients were acquired and analyzed. Parameters related to the linear regression of the power spectrum—midband fit, slope, and 0-MHz-intercept—were determined from breast tumors and normal breast tissues. Mean scatterer spacing was estimated from the spectral autocorrelation, and the effective scatterer diameter and effective acoustic concentration were estimated from the Gaussian form factor. Parametric maps of each quantitative ultrasound parameter were constructed from the gated radiofrequency segments in tumor and normal tissue regions of interest. In addition to the mean values of the parametric maps, higher order statistical features, computed from gray-level co-occurrence matrices were also determined and used for characterization. Finally, linear and quadratic discriminant analyses were performed using combinations of quantitative ultrasound parameters to classify breast tissues. Results: Quantitative ultrasound parameters were found to be statistically different between tumor and normal tissue (p < 0.05). The combination of effective acoustic concentration and mean scatterer spacing could separate tumor from normal tissue with 82% accuracy, while the addition of effective scatterer diameter to the combination did not provide significant improvement (83% accuracy). Furthermore, the two advanced parameters, including effective scatterer diameter and mean scatterer spacing, were found to be statistically differentiating among grade I, II, and III tumors (p = 0.014 for scatterer spacing, p = 0.035 for effective scatterer diameter). The separation of the tumor

  7. A quantitative approach for hydrological drought characterization in southwestern China using GRACE

    Science.gov (United States)

    Chao, Nengfang; Wang, Zhengtao; Jiang, Weiping; Chao, Dingbo

    2016-06-01

    A quantitative approach for hydrological drought characterization, based on non-seasonal water storage deficit data from NASA's Gravity Recovery and Climate Experiment (GRACE) satellite mission, is assessed. Non-seasonal storage deficit is the negative terrestrial water storage after deducting trend, acceleration and seasonal signals, and it is designated as a drought event when it persists for three or more continuous months. The non-seasonal water storage deficit is used for measuring the hydrological drought in southwestern China. It is found that this storage-deficit method clearly identifies hydrological drought onset, end and duration, and quantifies instantaneous severity, peak drought magnitude, and time to recovery. Moreover, it is found that severe droughts have frequently struck southwestern China in the past several decades, among which, the drought of 2011-2012 was the most severe; the duration was 10 months, the severity was -208.92 km3/month, and the time to recovery was 17 months. These results compare well with the National Climate Center of China drought databases, which signifies that the GRACE-based non-seasonal water storage deficit has a quantitative effect on hydrological drought characterization and provides an effective tool for researching droughts.

  8. Highly Quantitative Electrochemical Characterization of Non-Aqueous Electrolytes & Solid Electrolyte Interphases

    Energy Technology Data Exchange (ETDEWEB)

    Sergiy V. Sazhin; Kevin L. Gering; Mason K. Harrup; Harry W. Rollins

    2012-10-01

    The methods to measure solid electrolyte interphase (SEI) electrochemical properties and SEI formation capability of non-aqueous electrolyte solutions are not adequately addressed in the literature. And yet, there is a strong demand in new electrolyte generations that promote stabilized SEIs and have an influence to resolve safety, calendar life and other limitations of Li-ion batteries. To fill this gap, in situ electrochemical approach with new descriptive criteria for highly quantitative characterization of SEI and electrolytes is proposed. These criteria are: SEI formation capacity, SEI corrosion rate, SEI maintenance rate, and SEI kinetic stability. These criteria are associated with battery parameters like irreversible capacity, self-discharge, shelf-life, power, etc. Therefore, they are especially useful for electrolyte development and standard fast screening, allowing a skillful approach to narrow down the search for the best electrolyte. The characterization protocol also allows retrieving information on interfacial resistance for SEI layers and the electrochemical window of electrolytes, the other important metrics of characterization. The method validation was done on electrolyte blends containing phosphazenes, developed at Idaho National Laboratory, as 1.2M LiPF6 [80 % EC-MEC (2:8) (v/v) + 20% Phosphazene variety] (v/v), which were targeted for safer electrolyte variations.

  9. COMPARATIVE, QUALITATIVE AND QUANTITATIVE CHEMOTYPIC CHARACTERIZATION AMONG NORTH INDIAN TRIBULUS TERRESTRIS

    Directory of Open Access Journals (Sweden)

    Kumar Ashwani

    2012-06-01

    Full Text Available In India, Several medicinal plant species are used in herbal drug industries, whereas Tribulus terrestris extract has an ancient tradition in folk medicine and in ayurveda as a diuretic, mood enhancer, antiseptic and anti-inflammatory agent. Due to few phytochemical and pharmacological studies, there are no quality criteria for this Tribulus terrestris species as raw material. In this work, we present unique fingerprints of six samples of Tribulus terrestris population relating to the presence of flavonoids, alkaloid and saponins. Qualitative analysis of the phytochemicals of methanolic extracts revealed the presence of carbohydrates, saponins, phytosterols, phenols, flavonoids and tannins in all the plants. Quantitative analysis showed that the crude saponin was the major phytochemical constituent present in highest percentage followed by crude tannin in all six plants. These chemical characterizations can provide, for example, authentication of samples, detection of adulterations, and differentiation between closely related species.

  10. Quantitative characterization of the microstructure and properties of nanocrystalline WC–Co bulk

    International Nuclear Information System (INIS)

    Graphical abstract: Microstructure of the nanocrystalline WC–Co cermet bulk was quantitatively described by transmission electron microscopy based precession electron diffraction technology. It is discovered that the fraction of the Σ2 grain boundaries increases with the decrease of WC grain size. The effect of microstructure on mechanical properties depends on Co distribution, Σ2 boundaries fraction and WC grain contiguity. -- Nanocrystalline WC–Co bulk was prepared using a novel route that combined in situ reactions and subsequent spark plasma sintering. The microstructure was characterized by transmission electron microscopy-based precession electron diffraction technology. The nanocrystalline microstructure has a high WC grain contiguity. The fraction of Σ2 boundaries increases with a decrease in WC grain size. The effect of microstructure on the mechanical properties was analyzed in terms of the correlations between Co distribution, Σ2 boundary fraction and WC grain contiguity.

  11. a Quantitative Procedure for the Spatial Characterization of Urban Land Use

    Science.gov (United States)

    Decraene, James; Monterola, Christopher; Lee, Gary Kee Khoon; Hung, Terence Gih Guang

    2013-02-01

    We have developed a procedure that characterizes the land use pattern of an urban system using: (a) Spatial entropy that measures the extent of spread of residential, business and industrial sectors; and (b) Index of dissimilarity that quantifies the degree of mixing in space of different sectors. The approach is illustrated by using the land use zoning maps of the city state of Singapore and a selection of North American cities. We show that a common feature of most cities is for the industrial areas to be highly clustered while at the same time segregated from the residential or business districts. We also demonstrate that the combination of entropy of residential and dissimilarity index between residential and business areas provides a quantitative and potentially useful means of differentiating the land use pattern of different cities.

  12. Quantitative characterization of nonstructural carbohydrates of mezcal Agave (Agave salmiana Otto ex Salm-Dick).

    Science.gov (United States)

    Michel-Cuello, Christian; Juárez-Flores, Bertha Irene; Aguirre-Rivera, Juan Rogelio; Pinos-Rodríguez, Juan Manuel

    2008-07-23

    Fructans are the reserve carbohydrates in Agave spp. plants. In mezcal factories, fructans undergoes thermal hydrolysis to release fructose and glucose, which are the basis to produce this spirit. Carbohydrate content determines the yield of the final product, which depends on plant organ, ripeness stage, and thermal hydrolysis. Thus, a qualitative and quantitative characterization of nonstructural carbohydrates was conducted in raw and hydrolyzed juices extracted from Agave salmiana stems and leaves under three ripeness stages. By high-performance liquid chromatography (HPLC), fructose, glucose, sucrose, xylose, and maltose were identified in agave juice. Only the plant fraction with hydrolysis interaction was found to be significant in the glucose concentration plant. Interactions of the fraction with hydrolysis and ripeness with hydrolysis were statistically significant in fructose concentration. Fructose concentration rose considerably with hydrolysis, but only in juice extracted from ripe agave stems (early mature and castrated). This increase was statistically significant only with acid hydrolysis.

  13. Impact Assessment of Abiotic Resources in LCA: Quantitative Comparison of Selected Characterization Models

    DEFF Research Database (Denmark)

    Rørbech, Jakob Thaysen; Vadenbo, Carl; Hellweg, Stefanie;

    2014-01-01

    Resources have received significant attention in recent years resulting in development of a wide range of resource depletion indicators within life cycle assessment (LCA). Understanding the differences in assessment principles used to derive these indicators and the effects on the impact assessment...... results is critical for indicator selection and interpretation of the results. Eleven resource depletion methods were evaluated quantitatively with respect to resource coverage, characterization factors (CF), impact contributions from individual resources, and total impact scores. We included 2247...... may be critical for impact assessment results. Although no consistent correlations between methods applying similar assessment models could be observed, all methods showed relatively high correlation regarding the assessment of energy resources. Finally, we classify the existing methods into three...

  14. Characterization of ubiquitination dependent dynamics in growth factor receptor signaling by quantitative proteomics

    DEFF Research Database (Denmark)

    Akimov, Vyacheslav; Rigbolt, Kristoffer T G; Nielsen, Mogens M;

    2011-01-01

    or chains of ubiquitin molecules of various types and lengths to targeted proteins is known to alter proteins' lifespan, localization and function and to modulate protein interactions. Despite its central importance in various aspects of cellular life and function there are only a limited number of reports...... investigating ubiquitination on a proteomic scale, mainly due to the inherited complexity and heterogeneity of ubiquitination. We describe here a quantitative proteomics strategy based on the specificity of ubiquitin binding domains (UBDs) and Stable Isotope Labeling by Amino acids in Cell culture (SILAC......) for selectively decoding ubiquitination-driven processes involved in the regulation of cellular signaling networks. We applied this approach to characterize the temporal dynamics of ubiquitination events accompanying epidermal growth factor receptor (EGFR) signal transduction. We used recombinant UBDs derived...

  15. Quantitative breast tissue characterization using grating-based x-ray phase-contrast imaging

    International Nuclear Information System (INIS)

    X-ray phase-contrast imaging has received growing interest in recent years due to its high capability in visualizing soft tissue. Breast imaging became the focus of particular attention as it is considered the most promising candidate for a first clinical application of this contrast modality. In this study, we investigate quantitative breast tissue characterization using grating-based phase-contrast computed tomography (CT) at conventional polychromatic x-ray sources. Different breast specimens have been scanned at a laboratory phase-contrast imaging setup and were correlated to histopathology. Ascertained tumor types include phylloides tumor, fibroadenoma and infiltrating lobular carcinoma. Identified tissue types comprising adipose, fibroglandular and tumor tissue have been analyzed in terms of phase-contrast Hounsfield units and are compared to high-quality, high-resolution data obtained with monochromatic synchrotron radiation, as well as calculated values based on tabulated tissue properties. The results give a good impression of the method’s prospects and limitations for potential tumor detection and the associated demands on such a phase-contrast breast CT system. Furthermore, the evaluated quantitative tissue values serve as a reference for simulations and the design of dedicated phantoms for phase-contrast mammography. (paper)

  16. Quantitative performance characterization of three-dimensional noncontact fluorescence molecular tomography

    Science.gov (United States)

    Favicchio, Rosy; Psycharakis, Stylianos; Schönig, Kai; Bartsch, Dusan; Mamalaki, Clio; Papamatheakis, Joseph; Ripoll, Jorge; Zacharakis, Giannis

    2016-02-01

    Fluorescent proteins and dyes are routine tools for biological research to describe the behavior of genes, proteins, and cells, as well as more complex physiological dynamics such as vessel permeability and pharmacokinetics. The use of these probes in whole body in vivo imaging would allow extending the range and scope of current biomedical applications and would be of great interest. In order to comply with a wide variety of application demands, in vivo imaging platform requirements span from wide spectral coverage to precise quantification capabilities. Fluorescence molecular tomography (FMT) detects and reconstructs in three dimensions the distribution of a fluorophore in vivo. Noncontact FMT allows fast scanning of an excitation source and noninvasive measurement of emitted fluorescent light using a virtual array detector operating in free space. Here, a rigorous process is defined that fully characterizes the performance of a custom-built horizontal noncontact FMT setup. Dynamic range, sensitivity, and quantitative accuracy across the visible spectrum were evaluated using fluorophores with emissions between 520 and 660 nm. These results demonstrate that high-performance quantitative three-dimensional visible light FMT allowed the detection of challenging mesenteric lymph nodes in vivo and the comparison of spectrally distinct fluorescent reporters in cell culture.

  17. Quantitative breast tissue characterization using grating-based x-ray phase-contrast imaging

    Science.gov (United States)

    Willner, M.; Herzen, J.; Grandl, S.; Auweter, S.; Mayr, D.; Hipp, A.; Chabior, M.; Sarapata, A.; Achterhold, K.; Zanette, I.; Weitkamp, T.; Sztrókay, A.; Hellerhoff, K.; Reiser, M.; Pfeiffer, F.

    2014-04-01

    X-ray phase-contrast imaging has received growing interest in recent years due to its high capability in visualizing soft tissue. Breast imaging became the focus of particular attention as it is considered the most promising candidate for a first clinical application of this contrast modality. In this study, we investigate quantitative breast tissue characterization using grating-based phase-contrast computed tomography (CT) at conventional polychromatic x-ray sources. Different breast specimens have been scanned at a laboratory phase-contrast imaging setup and were correlated to histopathology. Ascertained tumor types include phylloides tumor, fibroadenoma and infiltrating lobular carcinoma. Identified tissue types comprising adipose, fibroglandular and tumor tissue have been analyzed in terms of phase-contrast Hounsfield units and are compared to high-quality, high-resolution data obtained with monochromatic synchrotron radiation, as well as calculated values based on tabulated tissue properties. The results give a good impression of the method’s prospects and limitations for potential tumor detection and the associated demands on such a phase-contrast breast CT system. Furthermore, the evaluated quantitative tissue values serve as a reference for simulations and the design of dedicated phantoms for phase-contrast mammography.

  18. Quantitative characterization of disease severity in diseases with complex symptom profiles.

    Science.gov (United States)

    Kondraske, George V; Stewart, R Malcolm

    2006-01-01

    A number of clinical and research situations arise that require the integration of complex, multi-dimensional, performance-related information to determine a single quantity such as "disease severity" or "risk level" (for subsequent development of a disease). This process is generally carried out either by relying on a subjective gestalt approach or by using rating scales that combine scores for component measures using an additive process without justification. Concepts from general systems performance theory have provided insights into this problem, teaching that a fundamentally multiplicative method of integrating components is often appropriate. In this paper, concepts and previous supportive experimental work are reviewed in the context of the quantitative characterization of disease severity. A Parkinson's disease study (n=114) is presented that mimics the "two-condition" situation encountered in the clinical trial of a new drug or other therapy. Traditional and performance theory-based composite scores are computed for each condition ("on" and "off" medications) and compared, with emphasis on the different quantitative "pictures" conveyed by each approach. It is concluded that performance theory based composites are not only more sensitive to therapeutic agents experimentally, but also have superior conceptual validity compared to traditional forms of single-number composites. PMID:17946592

  19. Tree Root System Characterization and Volume Estimation by Terrestrial Laser Scanning and Quantitative Structure Modeling

    Directory of Open Access Journals (Sweden)

    Aaron Smith

    2014-12-01

    Full Text Available The accurate characterization of three-dimensional (3D root architecture, volume, and biomass is important for a wide variety of applications in forest ecology and to better understand tree and soil stability. Technological advancements have led to increasingly more digitized and automated procedures, which have been used to more accurately and quickly describe the 3D structure of root systems. Terrestrial laser scanners (TLS have successfully been used to describe aboveground structures of individual trees and stand structure, but have only recently been applied to the 3D characterization of whole root systems. In this study, 13 recently harvested Norway spruce root systems were mechanically pulled from the soil, cleaned, and their volumes were measured by displacement. The root systems were suspended, scanned with TLS from three different angles, and the root surfaces from the co-registered point clouds were modeled with the 3D Quantitative Structure Model to determine root architecture and volume. The modeling procedure facilitated the rapid derivation of root volume, diameters, break point diameters, linear root length, cumulative percentages, and root fraction counts. The modeled root systems underestimated root system volume by 4.4%. The modeling procedure is widely applicable and easily adapted to derive other important topological and volumetric root variables.

  20. Morphologic characterization and quantitative analysis on in vitro bacteria by nuclear techniques of measurement

    International Nuclear Information System (INIS)

    The great difficulty to identify microorganisms (bacteria) from infectious processes is related to the necessary time to obtain a reliable result, about 72 hours. The purpose of this work is to establish a faster method to characterize bacterial morphologies through the use of neutron radiography, which can take about 5 hours. The samples containing the microorganisms, bacteria with different morphologies, after the appropriate microbiologic procedures were incubated with B10 for 30 minutes and soon after deposited in a plate of a solid detector of nuclear tracks (SSNTD), denominated CR-39. To obtain the images relative to bacteria, the detector was submitted to the flow of thermal neutrons of the order of 2.2 x 105 n/cm2.s from the J-9 channel of the Reactor Argonauta (IEN/CNEN). To observe the images from bacteria in each sample under an optical microscope, the sheets were chemically developed. The analysis of the images revealed morphologic differences among the genera (Gram positive from Gram-negative and coccus from bacillus), in samples containing either isolated or mixed bacteria. We thus verified the viability of the technique to achieve morphological characterization of different microorganisms. A quantitative approach seemed also to be feasible with the technique. The whole process took about 2 hours. (author)

  1. Quantitative characterization of glycan-receptor binding of H9N2 influenza A virus hemagglutinin.

    Directory of Open Access Journals (Sweden)

    Karunya Srinivasan

    Full Text Available Avian influenza subtypes such as H5, H7 and H9 are yet to adapt to the human host so as to establish airborne transmission between humans. However, lab-generated reassorted viruses possessing hemagglutinin (HA and neuraminidase (NA genes from an avian H9 isolate and other genes from a human-adapted (H3 or H1 subtype acquired two amino acid changes in HA and a single amino acid change in NA that confer respiratory droplet transmission in ferrets. We previously demonstrated for human-adapted H1, H2 and H3 subtypes that quantitative binding affinity of their HA to α2→6 sialylated glycan receptors correlates with respiratory droplet transmissibility of the virus in ferrets. Such a relationship remains to be established for H9 HA. In this study, we performed a quantitative biochemical characterization of glycan receptor binding properties of wild-type and mutant forms of representative H9 HAs that were previously used in context of reassorted viruses in ferret transmission studies. We demonstrate here that distinct molecular interactions in the glycan receptor-binding site of different H9 HAs affect the glycan-binding specificity and affinity. Further we show that α2→6 glycan receptor-binding affinity of a mutant H9 HA carrying Thr-189→Ala amino acid change correlates with the respiratory droplet transmission in ferrets conferred by this change. Our findings contribute to a framework for monitoring the evolution of H9 HA by understanding effects of molecular changes in HA on glycan receptor-binding properties.

  2. Validation of putative reference genes for gene expression studies in human hepatocellular carcinoma using real-time quantitative RT-PCR

    International Nuclear Information System (INIS)

    Reference genes, which are often referred to as housekeeping genes are frequently used to normalize mRNA levels between different samples in quantitative reverse transcription polymerase chain reaction (qRT-PCR). The selection of reference genes is critical for gene expression studies because the expression of these genes may vary among tissues or cells and may change under certain circumstances. Here, a systematic evaluation of six putative reference genes for gene expression studies in human hepatocellular carcinoma (HCC) is presented. Six genes, beta-2-microglobulin (B2M), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), hydroxymethyl-bilane synthase (HMBS), hypoxanthine phosphoribosyl-transferase 1 (HPRT1), succinate dehydrogenase complex, subunit A (SDHA) and ubiquitin C (UBC), with distinct functional characteristics and expression patterns were evaluated by qRT-PCR. Inhibitory substances in RNA samples were quantitatively assessed and controlled using an external RNA control. The stability of selected reference genes was analyzed using both geNorm and NormFinder software. HMBS and GAPDH were identified as the optimal reference genes for normalizing gene expression data between paired tumoral and adjacent non-tumoral tissues derived from patients with HCC. HMBS, GAPDH and UBC were identified to be suitable for the normalization of gene expression data among tumor tissues; whereas the combination of HMBS, B2M, SDHA and GAPDH was suitable for normalizing gene expression data among five liver cancer cell lines, namely Hep3B, HepG2, HuH7, SK-HEP-1 and SNU-182. The determined gene stability was increased after exclusion of RNA samples containing relatively higher inhibitory substances. Of six genes studied, HMBS was found to be the single best reference gene for gene expression studies in HCC. The appropriate choice of combination of more than one reference gene to improve qRT-PCR accuracy depends on the kind of liver tissues or cells under investigation

  3. Dual-porosity poroviscoelasticity and quantitative hydromechanical characterization of the brain tissue with experimental hydrocephalus data.

    Science.gov (United States)

    Mehrabian, Amin; Abousleiman, Younane N; Mapstone, Timothy B; El-Amm, Christian A

    2015-11-01

    Hydromechanical brain models often involve constitutive relations which must account for soft tissue deformation and creep, together with the interstitial fluid movement and exchange through capillaries. The interaction of rather unknown mechanisms which produce, absorb, and circulate the cerebrospinal fluid within the central nervous system can further add to their complexity. Once proper models for these phenomena or processes are selected, estimation of the associated parameters could be even more challenging. This paper presents the results of a consistent, coupled poroviscoelastic modeling and characterization of the brain tissue as a dual-porosity system. The model draws from Biot's theory of poroviscoelasticity, and adopts the generalized Kelvin's rheological description of the viscoelastic tissue behavior. While the interstitial space serves as the primary porosity through which the bulk flow of the interstitial fluid occurs, a secondary porosity network comprising the capillaries and venous system allows for its partial absorption into the blood. The correspondence principle is used in deriving a time-dependent analytical solution to the proposed model. It allows for identical poroelastic formulation of the original poroviscoelastic problem in the Laplace transform space. Hydrocephalus generally refers to a class of medical conditions which share the ventricles enlargement as a common feature. A set of published data from induced hydrocephalus and follow-up perfusion of cats' brains is used for quantitative characterization of the proposed model. A selected portion of these data including the ventricular volume and rate of fluid absorption from the perfused brain, together with the forward model solution, is utilized via an inverse problem technique to find proper estimations of the model parameters. Results show significant improvement in model predictions of the experimental data. The convoluted and coupled solution results are presented through the time

  4. Quantitative characterization of the surface topography of rolled sheets by laser scanning microscopy and fourier transformation

    Science.gov (United States)

    Gjønnes, Liv

    1996-08-01

    The surface of twin-roll cast aluminum sheets undergoes dramatic changes during cold rolling. This is mainly due to variables in the roll gap, topography of the rolls, lubrication, material properties, and in particular the initial structure and topography of the cast sheet. Therefore, it is important to have means to quantitatively describe the changes in the surface structure of each pass and from pass to pass in order to optimize the desired final surface structure. To achieve this, the laser scanning microscope (LSM) with its confocal technique has been employed to image the three-dimensional (3-D) topography and to digitize the image for further computer analysis. The digitization of the image is primarily motivated by the need to introduce a Fourier transformation of the surface topography. The method is effective in describing qualitative periodic trends in the surface features. Information is gained on the shape and periodicities as well as roughness directionality. For instance, grooves and cross hatches and their remnants can be followed from one pass to the other. Important characteristics of the surface topography such as rolling ridges and shingles can also easily be characterized.

  5. Quantitative mineralogical characterization of chrome ore beneficiation plant tailing and its beneficiated products

    Science.gov (United States)

    Das, S. K.

    2015-04-01

    Mineralogical characterization and liberation of valuable minerals are primary concerns in mineral processing industries. The present investigation focuses on quantitative mineralogy, elemental deportment, and locking-liberation characteristics of the beneficiation of tailings from a chrome ore beneficiation plant in the Sukinda region, Odisha; methods used for the study of the beneficiated tailings are QEMSCAN®, X-ray diffraction (XRD), and mineral chemistry by a scanning electron microscope equipped with an energy-dispersive spectrometer (SEM-EDS). The tailing sample was fine grained (69.48wt% below 45 μm size), containing 20.25wt% Cr2O3 and 39.19wt% Fe2O3, with a Cr:Fe mass ratio of 0.51. Mineralogical investigations using QEMSCAN studies revealed that chromite, goethite, and gibbsite are the dominant mineral phases with minor amounts of hematite, kaolinite, and quartz. The sample contained 34.22wt% chromite, and chromite liberation is more than 80% for grains smaller than 250 μm in size. Based on these results, it was predicted that liberated chromite and high-grade middling chromite particles could be separated from the gangue by various concentration techniques. The tailing sample was beneficiated by hydrocyclone, tabling, wet high-intensity magnetic separation (WHIMS), and flotation in order to recover the chromite. A chromite concentrate with 45.29wt% Cr2O3 and a Cr:Fe mass ratio of 1.85 can be produced from these low-grade chromite ore beneficiation plant rejects.

  6. Mammographic quantitative image analysis and biologic image composition for breast lesion characterization and classification

    Energy Technology Data Exchange (ETDEWEB)

    Drukker, Karen, E-mail: kdrukker@uchicago.edu; Giger, Maryellen L.; Li, Hui [Department of Radiology, University of Chicago, Chicago, Illinois 60637 (United States); Duewer, Fred; Malkov, Serghei; Joe, Bonnie; Kerlikowske, Karla; Shepherd, John A. [Radiology Department, University of California, San Francisco, California 94143 (United States); Flowers, Chris I. [Department of Radiology, University of South Florida, Tampa, Florida 33612 (United States); Drukteinis, Jennifer S. [Department of Radiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612 (United States)

    2014-03-15

    Purpose: To investigate whether biologic image composition of mammographic lesions can improve upon existing mammographic quantitative image analysis (QIA) in estimating the probability of malignancy. Methods: The study population consisted of 45 breast lesions imaged with dual-energy mammography prior to breast biopsy with final diagnosis resulting in 10 invasive ductal carcinomas, 5 ductal carcinomain situ, 11 fibroadenomas, and 19 other benign diagnoses. Analysis was threefold: (1) The raw low-energy mammographic images were analyzed with an established in-house QIA method, “QIA alone,” (2) the three-compartment breast (3CB) composition measure—derived from the dual-energy mammography—of water, lipid, and protein thickness were assessed, “3CB alone”, and (3) information from QIA and 3CB was combined, “QIA + 3CB.” Analysis was initiated from radiologist-indicated lesion centers and was otherwise fully automated. Steps of the QIA and 3CB methods were lesion segmentation, characterization, and subsequent classification for malignancy in leave-one-case-out cross-validation. Performance assessment included box plots, Bland–Altman plots, and Receiver Operating Characteristic (ROC) analysis. Results: The area under the ROC curve (AUC) for distinguishing between benign and malignant lesions (invasive and DCIS) was 0.81 (standard error 0.07) for the “QIA alone” method, 0.72 (0.07) for “3CB alone” method, and 0.86 (0.04) for “QIA+3CB” combined. The difference in AUC was 0.043 between “QIA + 3CB” and “QIA alone” but failed to reach statistical significance (95% confidence interval [–0.17 to + 0.26]). Conclusions: In this pilot study analyzing the new 3CB imaging modality, knowledge of the composition of breast lesions and their periphery appeared additive in combination with existing mammographic QIA methods for the distinction between different benign and malignant lesion types.

  7. Mixed enzyme-linked immunosorbent assay (MELISA) for HLA class I antigen: a plasma membrane marker.

    Science.gov (United States)

    Bjerrum, O W; Borregaard, N

    1990-03-01

    This study introduces a simple, reproducible assay for HLA class I antigen using antibodies against beta 2-microglobulin and the heavy chain on HLA. The sandwich technique was named mixed enzyme-linked immunosorbent assay (MELISA), and was designed for identification of plasma membranes in neutrophil subcellular fractions. The subcellular localization of HLA was identical to that of other plasma membrane markers, [3H]concanavalin A and detergent-independent alkaline phosphatase, and was unchanged by stimulation of cells by weak and strong secretagogues. In addition to the presence as part of the HLA complex in the plasma membrane uncomplexed beta 2-microglobulin is present in the specific granules of neutrophils. However, the release of beta 2-microglobulin from intact neutrophils stimulated with formyl-methionylleucylphenylalanine was much higher than could be explained by exocytosis of specific granules. Subcellular fractionation studies demonstrated that beta 2-microglobulin is localized in fractions characterized by latent alkaline phosphatase and released from this novel secretory compartment in response to stimulation with formyl-methionylleucylphenylalanine. PMID:2181625

  8. Characterization of Membrane Protein Interactions in Plasma Membrane Derived Vesicles with Quantitative Imaging FRET

    Science.gov (United States)

    Sarabipour, Sarvenaz; Del Piccolo, Nuala; Hristova, Kalina

    2016-01-01

    CONSPECTUS Here we describe an experimental tool, termed Quantitative Imaging Förster Resonance Energy Transfer (QI-FRET), which enables the quantitative characterization of membrane protein interactions. The QI-FRET methodology allows us to acquire binding curves and calculate association constants for complex membrane proteins in the native plasma membrane environment. The method utilizes FRET detection, and thus requires that the proteins of interest are labeled with florescent proteins, either FRET donors or FRET acceptors. Since plasma membranes of cells have complex topologies precluding the acquisition of two-dimensional binding curves, the FRET measurements are performed in plasma membrane derived vesicles which bud off cells as a result of chemical or osmotic stress. The results overviewed here are acquired in vesicles produced with an osmotic vesiculation buffer developed in our laboratory, which does not utilize harsh chemicals. The concentrations of the donor-labeled and the acceptor-labeled proteins are determined, along with the FRET efficiencies, in each vesicle. The experiments utilize transient transfection, such that a wide variety of concentrations is sampled. Then, data from hundreds of vesicles are combined to yield dimerization curves. Here we discuss recent findings about the dimerization of receptor tyrosine kinases (RTKs), membrane proteins that control cell growth and differentiation via lateral dimerization in the plasma membrane. We focus on the dimerization of fibroblast growth factor receptor 3 (FGFR3), an RTK that plays a critically important role in skeletal development. We study the role of different FGFR3 domains in FGFR3 dimerization in the absence of ligand, and we show that FGFR3 extracellular domains inhibit unliganded dimerization, while contacts between the juxtamembrane domains, which connect the transmembrane domains to the kinase domains, stabilize the unliganded FGFR3 dimers. Since FGFR3 has been documented to harbor

  9. A single-chain fusion molecule consisting of peptide, major histocompatibility gene complex class I heavy chain and beta2-microglobulin can fold partially correctly, but binds peptide inefficiently

    DEFF Research Database (Denmark)

    Sylvester-Hvid, C; Buus, S

    1999-01-01

    The function of major histocompatibility complex class I (MHC-I) molecules is to sample peptides from the intracellular environment and present these peptides to CD8+ cytotoxic T lymphocytes (CTL). We have attempted to develop a general approach to produce large amounts of pure and active...

  10. The interaction of beta 2-microglobulin (beta 2m) with mouse class I major histocompatibility antigens and its ability to support peptide binding. A comparison of human and mouse beta 2m

    DEFF Research Database (Denmark)

    Pedersen, L O; Stryhn, A; Holter, T L;

    1995-01-01

    The function of major histocompatibility complex (MHC) class I molecules is to sample peptides derived from intracellular proteins and to present these peptides to CD8+ cytotoxic T lymphocytes. In this paper, biochemical assays addressing MHC class I binding of both peptide and beta 2-microglobul...

  11. Quantitative characterization of solid state phases by secondary neutral mass spectrometry

    Science.gov (United States)

    Oechsner, H.; Getto, R.; Kopnarski, M.

    2009-03-01

    The quantitative determination of chemical solid phases by secondary neutral mass spectrometry (SNMS) based on the quantitative character of this technique is described and demonstrated for several thin film structures. The intermetallic phases in a Ni-Zn coating on Fe are shown to be achieved directly from the concentration ratios determined by SNMS. When correlating the local elemental concentration tupels with the corresponding phase fractions by a matrix equation, the determination of chemical solid phase depth profiles becomes possible. This is exemplified by the detection of temperature induced chemical phases in Ni and Ti/Si films on SiC substrates.

  12. A method of quantitative characterization for the component of C/C composites based on the PLM video

    Science.gov (United States)

    Li, Y. X.; Qi, L. H.; Song, Y. S.; Li, H. J.

    2016-07-01

    PLM video is used for studying the microstructure of C/C composites, because it contains the structure and motion information at the same time. It means that PLM video could provide more comprehensive microstructure features of C/C composites, and then the microstructure could be quantitatively characterized by image processing. However, several unavoidable displacements still exist in the PLM video, which could occur during the process of image acquisition. Therefore, an image registration method was put forward to correct the displacements by the phase correlation, and further to achieve the quantitative characterization of component combined with image fusion and threshold segmentation based on the PLM video of C/C composites. Specifically, PLM video was decomposed to a frame sequence firstly. Then a series of processes was carried out on this basis, including selecting the frame as equal interval, segmenting the static and dynamic regions and correcting the relative displacements between the adjacent frames. Meanwhile, the result of image registration was verified through image fusion, and it indicates that the proposed method could eliminate the displacements effectively. Finally, some operations of image processing were used to segment the components and calculate their fractions, thus the quantitative calculation was achieved successfully.

  13. Quantitative characterization of agglomerates and aggregates of pyrogenic and precipitated amorphous silica nanomaterials by transmission electron microscopy

    Directory of Open Access Journals (Sweden)

    De Temmerman Pieter-Jan

    2012-06-01

    Full Text Available Abstract Background The interaction of a nanomaterial (NM with a biological system depends not only on the size of its primary particles but also on the size, shape and surface topology of its aggregates and agglomerates. A method based on transmission electron microscopy (TEM, to visualize the NM and on image analysis, to measure detected features quantitatively, was assessed for its capacity to characterize the aggregates and agglomerates of precipitated and pyrogenic synthetic amorphous silicon dioxide (SAS, or silica, NM. Results Bright field (BF TEM combined with systematic random imaging and semi-automatic image analysis allows measuring the properties of SAS NM quantitatively. Automation allows measuring multiple and arithmetically complex parameters simultaneously on high numbers of detected particles. This reduces operator-induced bias and assures a statistically relevant number of measurements, avoiding the tedious repetitive task of manual measurements. Access to multiple parameters further allows selecting the optimal parameter in function of a specific purpose. Using principle component analysis (PCA, twenty-three measured parameters were classified into three classes containing measures for size, shape and surface topology of the NM. Conclusion The presented method allows a detailed quantitative characterization of NM, like dispersions of precipitated and pyrogenic SAS based on the number-based distributions of their mean diameter, sphericity and shape factor.

  14. Quantitative Microstructural Characterization of Thick Aluminum Plates Heavily Deformed Using Equal Channel Angular Extrusion

    DEFF Research Database (Denmark)

    Mishin, Oleg; Segal, V.M.; Ferrasse, S.

    2012-01-01

    A detailed quantitative analysis of the microstructure has been performed in three orthogonal planes of 15-mm-thick aluminum plates heavily deformed via two equal channel angular extrusion (ECAE) routes. One route was a conventional route A with no rotation between passes. Another route involved ...

  15. Qualitative and quantitative characterization of the in vitro dehydration process of hydrogel contact lenses

    OpenAIRE

    González-Méijome, José Manuel; López-Alemany, António; Parafita, Manuel A.; Almeida, José B.; Refojo, Miguel F.

    2007-01-01

    PURPOSE: To investigate the in vitro dehydration process of conventional hydrogel and silicone-hydrogel contact lens materials. METHODS: Eight conventional hydrogel and five silicone-hydrogel contact lenses were dehydrated under controlled environmental conditions on an analytical balance. Data were taken at 1-min intervals and dehydration curves of cumulative dehydration (CD), valid dehydration (VD), and dehydration rate (DR) were obtained. Several quantitative descriptors of the dehydration...

  16. Quantitative characterization of myocardial infarction by cardiovascular magnetic resonance predicts future cardiovascular events in patients with ischemic cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Pauly John M

    2008-04-01

    Full Text Available Abstract Background Cardiovascular magnetic resonance (CMR can provide quantitative data of the myocardial tissue utilizing high spatial and temporal resolution along with exquisite tissue contrast. Previous studies have correlated myocardial scar tissue with the occurrence of ventricular arrhythmia. This study was conducted to evaluate whether characterization of myocardial infarction by CMR can predict cardiovascular events in patients with ischemic cardiomyopathy (ICM. Results We consecutively studied 86 patients with ICM (LVEF Conclusion Quantification of the scar volume and scar percentage by CMR is superior to LVEDV, LVESV, and LVEF in prognosticating the future likelihood of the development of cardiovascular events in patients with ICM.

  17. Quantitative radiological characterization of waste. Integration of gamma spectrometry and passive/active neutron assay

    Energy Technology Data Exchange (ETDEWEB)

    Simone, Gianluca; Mauro, Egidio; Gagliardi, Filippo; Gorello, Edoardo [Nucleco S.p.A., Rome (Italy)

    2016-06-15

    The radiological characterization of drums through Non-Destructive Assay (NDA) techniques commonly relies on gamma spectrometry. This paper introduces the procedure developed in Nucleco for the NDA radiological characterization of drums when the presence of Special Nuclear Material (SNM) is expected/observed. The procedure is based on the integration of a gamma spectrometry in SGS mode (Segmented Gamma Scanner) and a passive/active neutron assay. The application of this procedure is discussed on a real case of drums. The extension of the integration procedure to other gamma spectrometry systems is also discussed.

  18. Quantitative ultrasound tissue characterization in shoulder and thigh muscles – a new approach

    DEFF Research Database (Denmark)

    Nielsen, P.K.; Jensen, B.R.; Darvann, Tron Andre;

    2006-01-01

    the method for characterization of ultrasound images of the supraspinatus muscle, and the vastus lateralis muscle. Methods: Computerized texture analyses employing first-order and higher-order grey-scale statistics were developed to objectively characterize ultrasound images of m. supraspinatus and m. vastus......-contractile components than the supraspinatus muscle, and that the muscle was coarser. The image analyses supplemented each other and gave a more complete description of the tissue composition in the muscle than the mean grey-scale value alone....

  19. Development of a quantitative method for the characterization of hole quality during laser trepan drilling of high-temperature alloy

    Science.gov (United States)

    Zhang, Hongyu; Zhou, Ming; Wang, Yunlong; Zhang, Xiangchao; Yan, Yu; Wang, Rong

    2016-02-01

    Short-pulsed lasers are of significant industrial relevance in laser drilling, with an acceptable compromise between accuracy and efficiency. However, an intensive research with regard to qualitative and quantitative characterization of the hole quality has rarely been reported. In the present study, a series of through holes were fabricated on a high-temperature alloy workpiece with a thickness of 3 mm using a LASERTEC 80 PowerDrill manufacturing system, which incorporated a Nd:YAG millisecond laser into a five-axis positioning platform. The quality of the holes manufactured under different laser powers (80-140 W) and beam expanding ratios (1-6) was characterized by a scanning electron microscope associated with an energy-dispersive X-ray analysis, focusing mainly on the formation of micro-crack and recast layer. Additionally, the conicity and circularity of the holes were quantitatively evaluated by the apparent radius, root-mean-square deviation, and maximum deviation, which were calculated based on the extraction of hole edge through programming with MATLAB. The results showed that an amount of melting and spattering contents were presented at the entrance end and the exit end of the holes, and micro-cracks and recast layer (average thickness 15-30 µm) were detected along the side wall of the holes. The elemental composition of the melting and spattering contents and the recast layer was similar, with an obvious increase in the contents of O, Nb, and Cr and a great reduction in the contents of Fe and Ni in comparison with the bulk material. Furthermore, the conicity and circularity evaluation of the holes indicated that a laser power of 100 W and a beam expanding ratio of 4 or 5 represented the typical optimal drilling parameters in this specific experimental situation. It is anticipated that the quantitative method developed in the present study can be applied for the evaluation of hole quality in laser drilling and other drilling conditions.

  20. Quantitative characterization of solute transport processes in the laboratory using electrical resistivity tomography

    NARCIS (Netherlands)

    Korteland, S.

    2013-01-01

    The shallow subsurface is an important zone from a social, economical, and environmental point of view. The increased use of the shallow subsurface together with the call for its protection and sustainable exploitation have increased the need for tools to monitor and characterize the subsurface, as

  1. Quantitative characterization of crosstalk effects for friction force microscopy with scan-by-probe SPMs.

    Science.gov (United States)

    Prunici, Pavel; Hess, Peter

    2008-06-01

    If the photodetector and cantilever of an atomic force microscope (AFM) are not properly adjusted, crosstalk effects will appear. These effects disturb measurements of the absolute vertical and horizontal cantilever deflections, which are involved in friction force microscopy (FFM). A straightforward procedure is proposed to study quantitatively crosstalk effects observed in scan-by-probe SPMs. The advantage of this simple, fast, and accurate procedure is that no hardware change or upgrade is needed. The results indicate that crosstalk effects depend not only on the alignment of the detector but also on the cantilever properties, position, and detection conditions. The measurements may provide information on the origin of the crosstalk effect. After determination of its magnitude, simple correction formulas can be applied to correct the crosstalk effects and then the single-load wedge method, using a commercially available grating, can be employed for accurate calibration of the lateral force. PMID:18035500

  2. Quantitative characterization, classification and reconstruction of oocyst shapes of Eimeria species from cattle

    DEFF Research Database (Denmark)

    Sommer, C.

    1998-01-01

    by multivariate statistical techniques. The morphology of 810 Eimeria specimens was defined in binary (b/w) digital images by pixels of their oocyst outline. A Fourier transform of pixel positions yielded size and shape features. To classify coccidia, the quantitative data were employed in an agglomerative...... clustering by average linkage algorithm with equal weight assigned to size and shape. An inverse Fourier transform served to reconstruct oocyst outlines, i.e. outlines of average shape and size, from mean values of features in resulting clusters. Clusters were subsequently identified based on their average...... morphology by comparison with drawings of species in an earlier taxonomical work. Five hundred oocyst outlines were simulated for each cluster representing a species, and shape/size variability was presented in contour diagrams. Differences in species shapes, and correspondence in length and width, were seen...

  3. Quantitative roughness characterization and 3D reconstruction of electrode surface using cyclic voltammetry and SEM image

    Energy Technology Data Exchange (ETDEWEB)

    Dhillon, Shweta; Kant, Rama, E-mail: rkant@chemistry.du.ac.in

    2013-10-01

    Area measurements from cyclic voltammetry (CV) and image from scanning electron microscopy (SEM) are used to characterize electrode statistical morphology, 3D surface reconstruction and its electroactivity. SEM images of single phased materials correspond to two-dimensional (2D) projections of 3D structures, leading to an incomplete characterization. Lack of third dimension information in SEM image is circumvented using equivalence between denoised SEM image and CV area measurements. This CV-SEM method can be used to estimate power spectral density (PSD), width, gradient, finite fractal nature of roughness and local morphology of the electrode. We show that the surface morphological statistical property like distribution function of gradient can be related to local electro-activity. Electrode surface gradient micrographs generated here can provide map of electro-activity sites. Finally, the densely and uniformly packed small gradient over the Pt-surface is the determining criterion for high intrinsic electrode activity.

  4. Methodology for Quantitative Characterization of Fluorophore Photoswitching to Predict Superresolution Microscopy Image Quality

    Science.gov (United States)

    Bittel, Amy M.; Nickerson, Andrew; Saldivar, Isaac S.; Dolman, Nick J.; Nan, Xiaolin; Gibbs, Summer L.

    2016-07-01

    Single-molecule localization microscopy (SMLM) image quality and resolution strongly depend on the photoswitching properties of fluorophores used for sample labeling. Development of fluorophores with optimized photoswitching will considerably improve SMLM spatial and spectral resolution. Currently, evaluating fluorophore photoswitching requires protein-conjugation before assessment mandating specific fluorophore functionality, which is a major hurdle for systematic characterization. Herein, we validated polyvinyl alcohol (PVA) as a single-molecule environment to efficiently quantify the photoswitching properties of fluorophores and identified photoswitching properties predictive of quality SMLM images. We demonstrated that the same fluorophore photoswitching properties measured in PVA films and using antibody adsorption, a protein-conjugation environment analogous to labeled cells, were significantly correlated to microtubule width and continuity, surrogate measures of SMLM image quality. Defining PVA as a fluorophore photoswitching screening platform will facilitate SMLM fluorophore development and optimal image buffer assessment through facile and accurate photoswitching property characterization, which translates to SMLM fluorophore imaging performance.

  5. Quantitative Raman characterization of cross-linked collagen thin films as a model system for diagnosing early osteoarthritis

    Science.gov (United States)

    Wang, Chao; Durney, Krista M.; Fomovsky, Gregory; Ateshian, Gerard A.; Vukelic, Sinisa

    2016-03-01

    The onset of osteoarthritis (OA)in articular cartilage is characterized by degradation of extracellular matrix (ECM). Specifically, breakage of cross-links between collagen fibrils in the articular cartilage leads to loss of structural integrity of the bulk tissue. Since there are no broadly accepted, non-invasive, label-free tools for diagnosing OA at its early stage, Raman spectroscopyis therefore proposed in this work as a novel, non-destructive diagnostic tool. In this study, collagen thin films were employed to act as a simplified model system of the cartilage collagen extracellular matrix. Cross-link formation was controlled via exposure to glutaraldehyde (GA), by varying exposure time and concentration levels, and Raman spectral information was collected to quantitatively characterize the cross-link assignments imparted to the collagen thin films during treatment. A novel, quantitative method was developed to analyze the Raman signal obtained from collagen thin films. Segments of Raman signal were decomposed and modeled as the sum of individual bands, providing an optimization function for subsequent curve fitting against experimental findings. Relative changes in the concentration of the GA-induced pyridinium cross-links were extracted from the model, as a function of the exposure to GA. Spatially resolved characterization enabled construction of spectral maps of the collagen thin films, which provided detailed information about the variation of cross-link formation at various locations on the specimen. Results showed that Raman spectral data correlate with glutaraldehyde treatment and therefore may be used as a proxy by which to measure loss of collagen cross-links in vivo. This study proposes a promising system of identifying onset of OA and may enable early intervention treatments that may serve to slow or prevent osteoarthritis progression.

  6. A Morphological and Quantitative Characterization of Early Floral Development in Apple (Malus × domestica Borkh.)

    OpenAIRE

    Foster, Toshi; JOHNSTON, ROBYN; SELEZNYOVA, ALLA

    2003-01-01

    Apple is an important crop and a focus of research worldwide. However, some aspects of floral commitment and morphogenesis remain unclear. A detailed characterization of bourse shoot apex development was undertaken to provide a framework for future genetic, molecular and physiological studies. Eight morphologically distinct stages of shoot apex development, prior to winter dormancy, were defined. Based on measurements of meristem diameter, two stages of vegetative development were recognized....

  7. Quantitative characterization of microstructure of two phase materials : the case of pearlite

    OpenAIRE

    Walentek, Artur

    2007-01-01

    The strength of heavily drawn pearlitic wires can reach values exceeding 4GPa. However, to obtain this effect a careful control of the drawing process and of the pearlite microstructure is necessary. In the latter case, microstructural investigations should provide information allowing for an optimal design of a failure-free production process. Yet, the number of methods for the characterization of pearlite, despite a large variety of its possible microstructure forms, is limited. This, in tu...

  8. Quantitative characterization of highly efficient correlated photon-pair source using biexciton resonance.

    Science.gov (United States)

    Yamamoto, Yasuo; Oohata, Goro; Mizoguchi, Kohji

    2016-03-21

    A high efficiency method for the generation of correlated photon pairs accompanied by reliable means to characterize the efficiency of that process is needed in the study of entangled states, which have important potential applications in quantum information and quantum communication. In this study, we report the first characterization of the efficiency of generation of correlated photon pairs emitted from a CuCl single crystal using the biexciton-resonance hyper-parametric scattering (RHPS) method which is the highly efficient method of generation of correlated photon pairs. In order to characterize the generation efficiency and signal-to-noise ratio of correlated photon pairs using this method, we investigated the pump power dependence on the photon counting rate and coincidence counting rate under resonant excitation. The pump power dependence shows that the power characteristic of the photon counting rates changes from linear to quadratic dependence of the pump power. This behavior represents a superposition of contributions from correlated photon pairs and non-correlated photons. The analysis of the pump power dependence shows that one photon-pair is produced by a pump pulse with 2 x 106 photons. Moreover, the generation efficiency of this method obtained by calculating the number of generated photon pairs per pump power is comparable to that of several methods based on the χ(3) parametric process. PMID:27136797

  9. Linear Nitramine (DNDA-57): Synthesis, Scale-Up, Characterization, and Quantitative Estimation by GC/MS

    Science.gov (United States)

    Vijayalakshmi, R.; Naik, N. H.; Gore, G. M.; Sikder, A. K.

    2015-01-01

    Dinitro-diaza-alkanes (DNDA-57) are linear nitramine plasticizers and find use in low-temperature sensitivity coefficient propellants. DNDA-57 is a mixture of 2,4-dinitro-2,4-diazapentane (DNDA-5), 2,4-dinitro-2,4-diazahexane (DNDA-6), and 3,5-dinitro-3,5-diazaheptane (DNDA-7) with percentage composition of 40 ± 5%, 44 ± 5% and 11 ± 2%, respectively. The synthesis process of DNDA-57 was established with slight modification of the reaction parameters to obtain good yield and the process was scaled up. The synthesized compound was thoroughly characterized by spectroscopic as well as thermal methods. The present study emphasizes gas chromatographic-mass spectrometric (GC/MS) characterization by electron impact (EI) mode and chemical ionization (CI) mode to determine the fragmentation pattern. Further, the identified components were confirmed with general characterization. The study reveals that DNDA-5, DNDA-6, and DNDA-7 follow identical decomposition pattern. The friction and impact sensitivity study unveils the insensitive nature of DNDA-57.

  10. A Quantitative Characterization of Nucleoplasmin/Histone Complexes Reveals Chaperone Versatility.

    Science.gov (United States)

    Fernández-Rivero, Noelia; Franco, Aitor; Velázquez-Campoy, Adrian; Alonso, Edurne; Muga, Arturo; Prado, Adelina

    2016-01-01

    Nucleoplasmin (NP) is an abundant histone chaperone in vertebrate oocytes and embryos involved in storing and releasing maternal histones to establish and maintain the zygotic epigenome. NP has been considered a H2A-H2B histone chaperone, and recently it has been shown that it can also interact with H3-H4. However, its interaction with different types of histones has not been quantitatively studied so far. We show here that NP binds H2A-H2B, H3-H4 and linker histones with Kd values in the subnanomolar range, forming different complexes. Post-translational modifications of NP regulate exposure of the polyGlu tract at the disordered distal face of the protein and induce an increase in chaperone affinity for all histones. The relative affinity of NP for H2A-H2B and linker histones and the fact that they interact with the distal face of the chaperone could explain their competition for chaperone binding, a relevant process in NP-mediated sperm chromatin remodelling during fertilization. Our data show that NP binds H3-H4 tetramers in a nucleosomal conformation and dimers, transferring them to DNA to form disomes and tetrasomes. This finding might be relevant to elucidate the role of NP in chromatin disassembly and assembly during replication and transcription. PMID:27558753

  11. Quantitative magnetometry analysis and structural characterization of multisegmented cobalt–nickel nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Cantu-Valle, Jesus [Department of Physics and Astronomy, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249 (United States); Díaz Barriga-Castro, Enrique [Centro de Investigación de Ciencias Físico Matemáticas/Facultad de Ciencias Físico Matemáticas, Universidad Autónoma de Nuevo León, Pedro de Alba s/n, San Nicolás de Los Garza, Nuevo León 66450 (Mexico); Vega, Víctor; García, Javier [Departamento de Física, Universidad de Oviedo, Calvo Sotelo s/n, Oviedo 33007 (Spain); Mendoza-Reséndez, Raquel [Facultad de Ingeniería Mecánica y Eléctrica. Universidad Autónoma de Nuevo León, Pedro de Alba s/n, San Nicolás de Los Garza, Nuevo León 66450 (Mexico); Luna, Carlos [Centro de Investigación de Ciencias Físico Matemáticas/Facultad de Ciencias Físico Matemáticas, Universidad Autónoma de Nuevo León, Pedro de Alba s/n, San Nicolás de Los Garza, Nuevo León 66450 (Mexico); Manuel Prida, Víctor [Departamento de Física, Universidad de Oviedo, Calvo Sotelo s/n, Oviedo 33007 (Spain); and others

    2015-04-01

    Understanding and measuring the magnetic properties of an individual nanowire and their relationship with crystalline structure and geometry are of scientific and technological great interest. In this work, we report the localized study of the magnetic flux distribution and the undisturbed magnetization of a single ferromagnetic nanowire that poses a bar-code like structure using off-axis electron holography (EH) under Lorentz conditions. The nanowires were grown by template-assisted electrodeposition, using AAO templates. Electron holography allows the visualization of the magnetic flux distribution within and surroundings as well as its quantification. The magnetic analysis performed at individual nanowires was correlated with the chemical composition and crystalline orientation of the nanowires. - Highlights: • The structure-magnetic property relationship of CoNi nanowires is determined. • Off axis electron holography for the magnetic nanowires is used for the analysis. • The magnetization is quantitatively obtained from the retrieved phase images. • These results lead to a better comprehension of the magneto-crystalline phenomena.

  12. Characterization of Quantitative Trait Loci for Grain Minerals in Hexaploid Wheat (Triticum aestivum L.)

    Institute of Scientific and Technical Information of China (English)

    SHI Rong-li; TONG Yi-ping; JING Rui-lian; ZHANG Fu-suo; ZOU Chun-qin

    2013-01-01

    Wheat is an important source of essential minerals for human body. Breeding wheat with high grain mineral concentration thus benefits human health. The objective of present study was to identify quantitative trait loci (QTLs) controlling grain mineral concentration and to evaluate the relation between nitrogen (N) and other essential minerals in winter wheat. Wheat grains were harvested from field experiment which conducted in China and analyzed for this purpose. Forty-three QTLs controlling grain mineral concentration and nitrogen-related traits were detected by using a double haploid (DH) population derived from winter wheat varieties Hanxuan 10 and Lumai 14. Chromosomes 4D and 5A might be very important in controlling mineral status in wheat grains. Significant positive correlations were found between grain nitrogen concentration (GNC) and nutrients Fe, Mn, Cu, Mg concentrations (FeGC, MnGC, CuGC, MgGC). Flag leaf N concentration at anthesis (FLNC) significantly and positively correlated with GNC, FeGC, MnGC, and CuGC. The study extended our knowledge on minerals in wheat grains and suggested which interactions between minerals should be considered in future breeding program.

  13. Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

    Energy Technology Data Exchange (ETDEWEB)

    Castle, James W.; Molz, Fred W.; Bridges, Robert A.; Dinwiddie, Cynthia L.; Lorinovich, Caitlin J.; Lu, Silong

    2003-02-07

    This project involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation. The investigation was performed in collaboration with Chevron Production Company U.S.A. as an industrial partner, and incorporates data from the Temblor Formation in Chevron's West Coalinga Field, California. Improved prediction of interwell reservoir heterogeneity was needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contained approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley.

  14. Quantitative void characterization in structural ceramics using scanning laser acoustic microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Roth, D.J.; Generazio, E.R.; Baaklini, G.Y.

    1986-01-01

    The ability of scanning laser acoustic microscopy (SLAM) to characterize artificially seeded voids in sintered silicon nitride structural ceramic specimens was investigated. Using trigonometric relationships and Airy's diffraction theory, predictions of internal void depth and size were obtained from acoustic diffraction patterns produced by the voids. Agreement was observed between actual and predicted void depths. However, predicted void diameters were generally much greater than actual diameters. Precise diameter predictions are difficult to obtain due to measurement uncertainty and the limitations of 100 MHz SLAM applied to typical ceramic specimens.

  15. Quantitative characterization for dielectrophoretic behavior of biological cells using optical tweezers

    Science.gov (United States)

    Park, In Soo; Hee Park, Se; Woo Lee, Sang; Sung Yoon, Dae; Kim, Beop-Min

    2014-02-01

    We report a method to precisely quantify dielectrophoretic (DEP) forces and cutoff frequencies (fc) of viable and nonviable yeast cells. The method consists of a two-step process in which generated DEP forces act upon a cell through a micro-electrode device, followed by direct measurement of DEP forces using optical tweezers. DEP behaviors of viable and nonviable yeast cells are monitored as a function of AC frequency. We believe that the proposed method can be used as a powerful platform for cell-based assays to characterize the DEP behavior of various cell types including cancer and normal cells.

  16. A straightforward and quantitative approach for characterizing the photoactivation performance of optical highlighter fluorescent proteins

    Science.gov (United States)

    Liu, Jun; Pei, Zhiguo; Wang, Liang; Zhang, Zhihong; Zeng, Shaoqun; Huang, Zhen-Li

    2010-11-01

    Characterizing the photoactivation performance of highlighter fluorescence proteins (FPs) is crucial for screening better highlighter FPs and optimizing the photoactivation efficiency of a certain highlighter FP. Currently, photoactivation contrast and half-time values of photoactivation and photobleaching processes are used for such purpose. However, the relations among these parameters are not clear, and little guidance for practical experiments could be obtained from the half-time values. Here, we show that light dose dependent fluorescence curve, which is calculated from activation-intensity-dependent photoactivation and photobleaching rates, is capable of quantifying the photoactivation performance straightforwardly. Moreover, the photoactivation contrast is easily obtained from the curve.

  17. Quantitative characterization of fatty liver disease using x-ray scattering

    Science.gov (United States)

    Elsharkawy, Wafaa B.; Elshemey, Wael M.

    2013-11-01

    Nonalcoholic fatty liver disease (NAFLD) is a dynamic condition in which fat abnormally accumulates within the hepatocytes. It is believed to be a marker of risk of later chronic liver diseases, such as liver cirrhosis and carcinoma. The fat content in liver biopsies determines its validity for liver transplantation. Transplantation of livers with severe NAFLD is associated with a high risk of primary non-function. Moreover, NAFLD is recognized as a clinically important feature that influences patient morbidity and mortality after hepatic resection. Unfortunately, there is a lack in a precise, reliable and reproducible method for quantification of NAFLD. This work suggests a method for the quantification of NAFLD. The method is based on the fact that fatty liver tissue would have a characteristic x-ray scattering profile with a relatively intense fat peak at a momentum transfer value of 1.1 nm-1 compared to a soft tissue peak at 1.6 nm-1. The fat content in normal and fatty liver is plotted against three profile characterization parameters (ratio of peak intensities, ratio of area under peaks and ratio of area under fat peak to total profile area) for measured and Monte Carlo simulated x-ray scattering profiles. Results show a high linear dependence (R2>0.9) of the characterization parameters on the liver fat content with a reported high correlation coefficient (>0.9) between measured and simulated data. These results indicate that the current method probably offers reliable quantification of fatty liver disease.

  18. Molecular Characterization and SYBR Green Ⅰ-Based Quantitative PCR for Duck Hepatitis Virus Type 1

    Institute of Scientific and Technical Information of China (English)

    LUO Yu-jun; ZHANG Gui-hong; XU Xiao-qin; CHEN Jian-hong; LIAO Ming

    2008-01-01

    To determine the genomic sequence of a duck hepatitis virus type 1 (DHV-1) strain,real-time quantitative polyrnerase chain reaction (RTQ-PCR) assay based on SYBR Green Ⅰ technology was developed to target 3D gene of DHV-1.Comparative sequence analysis showed that the genome has a typical picornarivus genetic organization,and strain DHV-1 R genetic organaiztion is 5' untranslated region (UTR)-VPO-VP3-VP1-2A1-2A2-2B-2C-3A-3B-3C-3D-3' UTR,DHV-1 R has close relationship with Parechovirus,and has 95.1-99.1% nucleotide sequence identity with other DHV-1 strains.Based on the DHV-1 sequences in GenBank,three pairs of specific primers were designed to amplify DHV-1 using real-time PCR.The results showed that real-time PCR Tm value is 85.6℃ and the real-time PCR provides a broad dynamic range,detecting from 102 to 109 copies of DHV-1 cDNA per reaction.No cross-reactions were found in specimens containing DPV,AIV and NDV.It is concluded that DHV-1 belongs to a new group of the family Picornaviridae that may form a separate genus most closely related to the genus Parechovirus.All results showed that the real-time PCR has high sensitivity and specificity to detect DHV-1 using SYBR Green Ⅰ dissociation curve analysis,isolates can be distinguished by their melting temperature.These methods are rapid,sensitive,and reliable,and can be readily adapted for detection of DHV-1 from other clinical samples.

  19. Characterization of the gut microbiota of Papua New Guineans using reverse transcription quantitative PCR.

    Directory of Open Access Journals (Sweden)

    Andrew R Greenhill

    Full Text Available There has been considerable interest in composition of gut microbiota in recent years, leading to a better understanding of the role the gut microbiota plays in health and disease. Most studies have been limited in their geographical and socioeconomic diversity to high-income settings, and have been conducted using small sample sizes. To date, few analyses have been conducted in low-income settings, where a better understanding of the gut microbiome could lead to the greatest return in terms of health benefits. Here, we have used quantitative real-time polymerase chain reaction targeting dominant and sub-dominant groups of microorganisms associated with human gut microbiome in 115 people living a subsistence lifestyle in rural areas of Papua New Guinea. Quantification of Clostridium coccoides group, C. leptum subgroup, C. perfringens, Bacteroides fragilis group, Bifidobacterium, Atopobium cluster, Prevotella, Enterobacteriaceae, Enterococcus, Staphylococcus, and Lactobacillus spp. was conducted. Principle coordinates analysis (PCoA revealed two dimensions with Prevotella, clostridia, Atopobium, Enterobacteriaceae, Enterococcus and Staphylococcus grouping in one dimension, while B. fragilis, Bifidobacterium and Lactobacillus grouping in the second dimension. Highland people had higher numbers of most groups of bacteria detected, and this is likely a key factor for the differences revealed by PCoA between highland and lowland study participants. Age and sex were not major determinants in microbial population composition. The study demonstrates a gut microbial composition with some similarities to those observed in other low-income settings where traditional diets are consumed, which have previously been suggested to favor energy extraction from a carbohydrate rich diet.

  20. Characterization of the gut microbiota of Papua New Guineans using reverse transcription quantitative PCR.

    Science.gov (United States)

    Greenhill, Andrew R; Tsuji, Hirokazu; Ogata, Kiyohito; Natsuhara, Kazumi; Morita, Ayako; Soli, Kevin; Larkins, Jo-Ann; Tadokoro, Kiyoshi; Odani, Shingo; Baba, Jun; Naito, Yuichi; Tomitsuka, Eriko; Nomoto, Koji; Siba, Peter M; Horwood, Paul F; Umezaki, Masahiro

    2015-01-01

    There has been considerable interest in composition of gut microbiota in recent years, leading to a better understanding of the role the gut microbiota plays in health and disease. Most studies have been limited in their geographical and socioeconomic diversity to high-income settings, and have been conducted using small sample sizes. To date, few analyses have been conducted in low-income settings, where a better understanding of the gut microbiome could lead to the greatest return in terms of health benefits. Here, we have used quantitative real-time polymerase chain reaction targeting dominant and sub-dominant groups of microorganisms associated with human gut microbiome in 115 people living a subsistence lifestyle in rural areas of Papua New Guinea. Quantification of Clostridium coccoides group, C. leptum subgroup, C. perfringens, Bacteroides fragilis group, Bifidobacterium, Atopobium cluster, Prevotella, Enterobacteriaceae, Enterococcus, Staphylococcus, and Lactobacillus spp. was conducted. Principle coordinates analysis (PCoA) revealed two dimensions with Prevotella, clostridia, Atopobium, Enterobacteriaceae, Enterococcus and Staphylococcus grouping in one dimension, while B. fragilis, Bifidobacterium and Lactobacillus grouping in the second dimension. Highland people had higher numbers of most groups of bacteria detected, and this is likely a key factor for the differences revealed by PCoA between highland and lowland study participants. Age and sex were not major determinants in microbial population composition. The study demonstrates a gut microbial composition with some similarities to those observed in other low-income settings where traditional diets are consumed, which have previously been suggested to favor energy extraction from a carbohydrate rich diet.

  1. Quantitative characterization of the impact of pulp refining on enzymatic saccharification of the alkaline pretreated corn stover.

    Science.gov (United States)

    Xu, Huanfei; Li, Bin; Mu, Xindong; Yu, Guang; Liu, Chao; Zhang, Yuedong; Wang, Haisong

    2014-10-01

    In this work, corn stover was refined by a pulp refining instrument (PFI refiner) after NaOH pretreatment under varied conditions. The quantitative characterization of the influence of PFI refining on enzymatic hydrolysis was studied, and it was proved that the enhancement of enzymatic saccharification by PFI refining of the pretreated corn stover was largely due to the significant increment of porosity of substrates and the reduction of cellulose crystallinity. Furthermore, a linear relationship between beating degree and final total sugar yields was found, and a simple way to predict the final total sugar yields by easily testing the beating degree of PFI refined corn stover was established. Therefore, this paper provided the possibility and feasibility for easily monitoring the fermentable sugar production by the simple test of beating degree, and this will be of significant importance for the monitoring and controlling of industrial production in the future.

  2. Quantitative characterization of modulation-doped strained quantum wells through line-shape analysis of room-temperature photoluminescence spectra

    Science.gov (United States)

    Brierley, Steven K.

    1993-08-01

    Room-temperature photoluminescence (PL) was presented as a nondestructive characterization method for modulation-doped strained quantum well epitaxial structures suited for pseudomorphic high electron mobility transistors (pHEMTs). Though the spectra showed broad peaks, in contrast to the sharp, well-defined peaks in low-temperature PL spectra, quantitative energy data was obtained through fitting a phenomenological line-shape model to the spectra. This model included the four transitions linking the first two electron subbands and the first two heavy-hole subbands, which can take credit for all of the peaks noted in pHEMT epitaxial configurations at realistic doping levels. The obtained results revealed that by using a simple line-shape model to the room-temperature PL spectrum of a pHEMT, a substantial amount of detailed structural and electronic data can be acquired regarding the quantum well.

  3. Characterization of Expression Quantitative Trait Loci in Pedigrees from Colombia and Costa Rica Ascertained for Bipolar Disorder

    Science.gov (United States)

    Peterson, Christine B.; Service, Susan K.; Jasinska, Anna J.; Gao, Fuying; Zelaya, Ivette; Teshiba, Terri M.; Bearden, Carrie E.; Cantor, Rita M.; Reus, Victor I.; Macaya, Gabriel; López-Jaramillo, Carlos; Bogomolov, Marina; Benjamini, Yoav; Eskin, Eleazar; Coppola, Giovanni; Freimer, Nelson B.; Sabatti, Chiara

    2016-01-01

    The observation that variants regulating gene expression (expression quantitative trait loci, eQTL) are at a high frequency among SNPs associated with complex traits has made the genome-wide characterization of gene expression an important tool in genetic mapping studies of such traits. As part of a study to identify genetic loci contributing to bipolar disorder and other quantitative traits in members of 26 pedigrees from Costa Rica and Colombia, we measured gene expression in lymphoblastoid cell lines derived from 786 pedigree members. The study design enabled us to comprehensively reconstruct the genetic regulatory network in these families, provide estimates of heritability, identify eQTL, evaluate missing heritability for the eQTL, and quantify the number of different alleles contributing to any given locus. In the eQTL analysis, we utilize a recently proposed hierarchical multiple testing strategy which controls error rates regarding the discovery of functional variants. Our results elucidate the heritability and regulation of gene expression in this unique Latin American study population and identify a set of regulatory SNPs which may be relevant in future investigations of complex disease in this population. Since our subjects belong to extended families, we are able to compare traditional kinship-based estimates with those from more recent methods that depend only on genotype information. PMID:27176483

  4. Quantitative analysis of the precipitation conditions in fine grained structural steel for materials characterization

    International Nuclear Information System (INIS)

    In the framework of the preparation of the atlas of structures of structural materials, mechanical-technological, metallographic, phase-analytical and electron microscopic investigations were carried out on 17 melts (11 production and 6 test melts with graduated Al and N contents) of the material 15 NiCuMoNb 5 for the characterization of the welding properties. The investigations were focussed on the quantification of the microstructure parameters. The reason for the investigations was the occurrence of uncertainties concerning relaxation-induced cracking in welding. The results confirm the possibility of a decrease of the relaxation capacity by precipitation processes, which are favoured by coarse grain formation or expansion, as well as by grain boundary embrittlement. Which mechanism, however, takes effect depends essentially on the chemical composition of the melt. (orig./MM)

  5. Segmentation of nanotomographic cortical bone images for quantitative characterization of the osteoctyte lacuno-canalicular network

    Energy Technology Data Exchange (ETDEWEB)

    Ciani, A.; Kewish, C. M. [Synchrotron Soleil, L’Orme des Merisiers, 91192 Saint-Aubin (France); Guizar-Sicairos, M.; Diaz, A.; Holler, M. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Pallu, S.; Achiou, Z.; Jennane, R.; Toumi, H.; Lespessailles, E. [Univ Orléans, I3MTO, Ea 4708, 45000 Orléans (France)

    2016-01-28

    A newly developed data processing method able to characterize the osteocytes lacuno-canalicular network (LCN) is presented. Osteocytes are the most abundant cells in the bone, living in spaces called lacunae embedded inside the bone matrix and connected to each other with an extensive network of canals that allows for the exchange of nutrients and for mechanotransduction functions. The geometrical three-dimensional (3D) architecture is increasingly thought to be related to the macroscopic strength or failure of the bone and it is becoming the focus for investigating widely spread diseases such as osteoporosis. To obtain 3D LCN images non-destructively has been out of reach until recently, since tens-of-nanometers scale resolution is required. Ptychographic tomography was validated for bone imaging in [1], showing clearly the LCN. The method presented here was applied to 3D ptychographic tomographic images in order to extract morphological and geometrical parameters of the lacuno-canalicular structures.

  6. Quantitative Characterization of the Microstructure and Transport Properties of Biopolymer Networks

    CERN Document Server

    Jiao, Yang

    2012-01-01

    Biopolymer networks are of fundamental importance to many biological processes in normal and tumorous tissues. In this paper, we employ the panoply of theoretical and simulation techniques developed for characterizing heterogeneous materials to quantify the microstructure and effective diffusive transport properties (diffusion coefficient $D_e$ and mean survival time $\\tau$) of collagen type I networks at various collagen concentrations. In particular, we compute the pore-size probability density function $P(\\delta)$ for the networks and present a variety of analytical estimates of the effective diffusion coefficient $D_e$ for finite-sized diffusing particles. The Hashin-Strikman upper bound on the effective diffusion coefficient $D_e$ and the pore-size lower bound on the mean survival time $\\tau$ are used as benchmarks to test our analytical approximations and numerical results. Moreover, we generalize the efficient first-passage-time techniques for Brownian-motion simulations in suspensions of spheres to th...

  7. Quantitative characterization of articular cartilage using Mueller matrix imaging and multiphoton microscopy

    Science.gov (United States)

    Ellingsen, Pa˚L. Gunnar; Lilledahl, Magnus Borstad; Aas, Lars Martin Sandvik; Davies, Catharina De Lange; Kildemo, Morten

    2011-11-01

    The collagen meshwork in articular cartilage of chicken knee is characterized using Mueller matrix imaging and multiphoton microscopy. Direction and degree of dispersion of the collagen fibers in the superficial layer are found using a Fourier transform image-analysis technique of the second-harmonic generated image. Mueller matrix images are used to acquire structural data from the intermediate layer of articular cartilage where the collagen fibers are too small to be resolved by optical microscopy, providing a powerful multimodal measurement technique. Furthermore, we show that Mueller matrix imaging provides more information about the tissue compared to standard polarization microscopy. The combination of these techniques can find use in improved diagnosis of diseases in articular cartilage, improved histopathology, and additional information for accurate biomechanical modeling of cartilage.

  8. Organic matter produced by algae and cyanobacteria: Quantitative and qualitative characterization

    Institute of Scientific and Technical Information of China (English)

    Maud Leloup; Rudy Nicolau; Virginie Pallier; Claude Yéprémian; Geneviève Feuillade-Cathalifaud

    2013-01-01

    This work aims at characterizing organic matter produced by an alga Euglena gracilis and a cyanobacteria Microcystis aeruginosa and assessing the evolution of its characteristics during growth.A culture medium was optimized.The species growth phases were monitored using both visible spectrophotometry and flow cytometry cell counting.Organic matter fractionation according to hydrophobicity and specific UV absorbance (SUVA) index were used to specifically characterize the produced algal organic matter (AOM).The AOM characteristics were both growth phase and species dependent.However,a similar evolution was observed.The hydrophilic fraction (HPI) was the major fraction whatever the growth phases and was almost the only one produced during lag and exponential phases.It represented around 75% of AOM during exponential phase and then decreased when the stationary phase appeared.It represented 46% and 60% of the AOM during late decline phase for the cyanobacteria and the alga respectively.The hydrophobic (HPO) and transphilic (TPH) fractions started to appear from the beginning of the stationary phase with more hydrophobic compounds coming from intracellular organic material of dying cells.HPO and TPH percentages still increased during the decline phase probably because of two additional processes:photo-dissolution and leaching of particulate organic matter from cells fragments.A comparison of AOM during late decline phase and natural organic matter (NOM) from Glane River (France) underlined that AOM was more hydrophilic and presented a lower SUVA for each fractions than NOM.However,the difference between NOM and AOM hydrophobicity narrowed during decline phase.

  9. Quantitative characterization of the influence of the nanoscale morphology of nanostructured surfaces on bacterial adhesion and biofilm formation.

    Directory of Open Access Journals (Sweden)

    Ajay Vikram Singh

    Full Text Available Bacterial infection of implants and prosthetic devices is one of the most common causes of implant failure. The nanostructured surface of biocompatible materials strongly influences the adhesion and proliferation of mammalian cells on solid substrates. The observation of this phenomenon has led to an increased effort to develop new strategies to prevent bacterial adhesion and biofilm formation, primarily through nanoengineering the topology of the materials used in implantable devices. While several studies have demonstrated the influence of nanoscale surface morphology on prokaryotic cell attachment, none have provided a quantitative understanding of this phenomenon. Using supersonic cluster beam deposition, we produced nanostructured titania thin films with controlled and reproducible nanoscale morphology respectively. We characterized the surface morphology; composition and wettability by means of atomic force microscopy, X-ray photoemission spectroscopy and contact angle measurements. We studied how protein adsorption is influenced by the physico-chemical surface parameters. Lastly, we characterized Escherichia coli and Staphylococcus aureus adhesion on nanostructured titania surfaces. Our results show that the increase in surface pore aspect ratio and volume, related to the increase of surface roughness, improves protein adsorption, which in turn downplays bacterial adhesion and biofilm formation. As roughness increases up to about 20 nm, bacterial adhesion and biofilm formation are enhanced; the further increase of roughness causes a significant decrease of bacterial adhesion and inhibits biofilm formation. We interpret the observed trend in bacterial adhesion as the combined effect of passivation and flattening effects induced by morphology-dependent protein adsorption. Our findings demonstrate that bacterial adhesion and biofilm formation on nanostructured titanium oxide surfaces are significantly influenced by nanoscale morphological

  10. Characterization of Precipitates in a Microalloyed Steel Using Quantitative X-ray Diffraction

    Directory of Open Access Journals (Sweden)

    J. Barry Wiskel

    2016-04-01

    Full Text Available Quantitative X-ray diffraction (QXRD (also known as the Rietveld method was used to analyze the precipitates present in Grade 100 microalloyed steel. The precipitates were extracted from the steel using electrolytic dissolution and the residue from the dissolution was analyzed using XRD. The XRD pattern exhibited three (3 distinct diffraction peaks, and significant broadening of a fourth peak corresponding to the <10 nm size precipitates. QXRD analysis was applied to the XRD pattern to obtain precipitate size, composition, and weight fraction data for each of the four diffraction peaks observed. The predicted mean precipitate diameter and average atomic composition of the nano-size (<10 nm precipitates was 4.7 nm and (Nb0.50Ti0.32Mo0.18(C0.59N0.41, respectively. The predicted precipitate size correlates well with the average size of precipitates measured in previous work by the authors using both transmission electron microscopy (TEM and small angle neutron scattering (SANS. The average atomic composition correlates well with the composition measured in this work using energy dispersive X-ray (EDX analysis of individual nano-sized precipitates. The calculated weight fraction of the nano-size precipitates in the extracted residue was 42.2 wt. %. The calculated atomic compositions of the other three diffraction peaks were TiN, (Ti0.87Nb0.13N, and (Nb0.82Ti0.18(C0.87N0.13 with weight fraction values of 12.9 wt. %, 31.7 wt. %, and 13.1 wt. %, respectively. The sizes of both the (Ti0.87Nb0.13N and the (Nb0.82Ti0.18(C0.87N0.13 groups of precipitates were directly measured and were observed to range from 150 nm to 570 nm and from 90 nm to 475 nm, respectively. QXRD was unable to determine a reasonable mean precipitate size for either of these two groups of precipitates. The wide compositional range (i.e., varying levels of Nb and Ti of these precipitates (as measured by EDX resulted in XRD peak broadening that was erroneously interpreted as a size

  11. Quantitative nanoscale characterization of undulated silicon-germanium/silicon(100) epitaxial thin films

    Science.gov (United States)

    Wu, Chi-Chin

    Heteroepitaxial thin films are important for the fabrication of advanced devices and as model systems for understanding fundamental materials phenomena. Depending on the growth conditions, film thickness, and extent of lattice mismatch at the film/substrate interface during growth, the epitaxial film will undergo morphological surface evolution to help release the stored elastic strain energy. For low-mismatched structures, a compressively-strained film often roughens and/or forms misfit dislocations after achieving a characteristic thickness. Using undulated Si1-xGex/Si(100) thin films, this work focuses on measurement of quantitative nanoscale variations of compositional and strain/stress fields within roughened heteroepitaxial films. The research was initiated by calculating local and overall stresses for roughened films assuming a sinusoidal film geometry with finite element (FE) models. Chemical wet etching was then applied to experimentally determine the lateral variations of Ge composition within the undulated film. Additional FE modeling results indicated that such composition variations would contribute further overall stress reduction in the film. In-situ transmission electron microscopy (TEM) annealing experiments were performed to measure the dislocation propagation velocity in strained Si1-xGex films to explore the nanoscale correlations between stress variations and surface morphology. The local dislocation velocity data were translated into stresses using previously established stress-velocity relations developed for this system. The inferred stress variations correlated well spatially to the period of surface undulations. However, there was a large discrepancy in the stress variations between undulation peaks and troughs inferred from the local dislocation velocities compared to those calculated by FE models. A stress-dependent single-kink nucleation model was then successfully applied to reconcile these differences. The detailed local

  12. Quantitative analysis of the dual-energy CT virtual spectral curve for focal liver lesions characterization

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qi, E-mail: wq20@hotmail.com; Shi, Gaofeng, E-mail: gaofengs62@sina.com; Qi, Xiaohui, E-mail: qixiaohui1984@163.com; Fan, Xueli, E-mail: 407849960@qq.com; Wang, Lijia, E-mail: 893197597@qq.com

    2014-10-15

    Highlights: • We establish a feasible method using the virtual spectral curves (VSC) to differentiate focal liver lesions using DECT. • Our study shows the slope of the VSC can be used to differentiate between hemangioma, HCC, metastasis and cyst. • Importantly, the diagnostic specificities associated with using the slope to diagnose both hemangioma and cysts were 100%. - Abstract: Objective: To assess the usefulness of the spectral curve slope of dual-energy CT (DECT) for differentiating between hepatocellular carcinoma (HCC), hepatic metastasis, hemangioma (HH) and cysts. Methods: In total, 121 patients were imaged in the portal venous phase using dual-energy mode. Of these patients, 23 patients had HH, 28 patients had HCC, 40 patients had metastases and 30 patients had simple cysts. The spectral curves of the hepatic lesions were derived from the 40–190 keV levels of virtual monochromatic spectral imaging. The spectral curve slopes were calculated from 40 to 110 keV. The slopes were compared using the Kruskal–Wallis test. Receiver operating characteristic curves (ROC) were used to determine the optimal cut-off value of the slope of the spectral curve to differentiate between the lesions. Results: The spectral curves of the four lesion types had different baseline levels. The HH baseline level was the highest followed by HCC, metastases and cysts. The slopes of the spectral curves of HH, HCC, metastases and cysts were 3.81 ± 1.19, 1.49 ± 0.57, 1.06 ± 0.76 and 0.13 ± 0.17, respectively. These values were significantly different (P < 0.008). Based on ROC analysis, the respective diagnostic sensitivity and specificity were 87% and 100% for hemangioma (cut-off value ≥ 2.988), 82.1% and 65.9% for HCC (cut-off value 1.167–2.998), 65.9% and 59% for metastasis (cut-off value 0.133–1.167) and 44.4% and 100% for cysts (cut-off value ≤ 0.133). Conclusion: Quantitative analysis of the DECT spectral curve in the portal venous phase can be used to

  13. Quantitative Characterization of Nut Yield and Fruit Components in Indigenous Coconut Germplasm in Sri Lanka

    Directory of Open Access Journals (Sweden)

    S. A. C. N. Perera

    2014-01-01

    Full Text Available Coconut (Cocos nucifera L. is a tropical palm offering multiple uses. Conservation of coconut germplasm has been undertaken globally in view of its economic importance. This research was designed to evaluate nine Sri Lankan indigenous coconut germplasm representing the three varieties Typica, Nana, and Aurantiaca. Total annual nut yield and the weights of fresh nut, husked nut, split nut, and fresh and dry kernel were scored and analyzed with analysis of variance. The annual average number of bunches varied from 14.9 to 16.8 which is significantly higher than the generally accepted 12–14 bunches in tall coconuts. The high potential of phenotypes Ran thembili and Gon thembili for kernel production was revealed. The high potential of Gon thembili, Sri Lanka Tall, and Ran thembili to produce fibre was also identified. Phenotypes Ran thembili and Gon thembili displayed their potential as pure cultivars and as parents in hybridization. King coconut, Red dwarf, and Bodiri were shown to be suitable as beverage coconuts due to the high production of nuts, bunches, and the quantity of nut water. This study reiterated the importance of conservation and characterization of indigenous coconut varieties globally for their effective use in the genetic improvement of the coconut palm.

  14. Multi-technique approach for qualitative and quantitative characterization of furazidin degradation kinetics under alkaline conditions.

    Science.gov (United States)

    Bērziņš, Kārlis; Kons, Artis; Grante, Ilze; Dzabijeva, Diana; Nakurte, Ilva; Actiņš, Andris

    2016-09-10

    Degradation of drug furazidin was studied under different conditions of environmental pH (11-13) and temperature (30-60°C). The novel approach of hybrid hard- and soft-multivariate curve resolution-alternating least squares (HS-MCR-ALS) method was applied to UV-vis spectral data to determine a valid kinetic model and kinetic parameters of the degradation process. The system was found to be comprised of three main species and best characterized by two consecutive first-order reactions. Furazidin degradation rate was found to be highly dependent on the applied environmental conditions, showing more prominent differences between both degradation steps towards higher pH and temperature. Complimentary qualitative analysis of the degradation process was carried out using HPLC-DAD-TOF-MS. Based on the obtained chromatographic and mass spectrometric results, as well as additional computational analysis of the species (theoretical UV-vis spectra calculations utilizing TD-DFT methodology), the operating degradation mechanism was proposed to include formation of a 5-hydroxyfuran derivative, followed by complete hydrolysis of furazidin hydantoin ring.

  15. Advanced Mass Spectrometric Methods for the Rapid and Quantitative Characterization of Proteomes

    Directory of Open Access Journals (Sweden)

    Richard D. Smith

    2006-04-01

    Full Text Available Progress is reviewed towards the development of a global strategy that aims to extend the sensitivity, dynamic range, comprehensiveness and throughput of proteomic measurements based upon the use of high performance separations and mass spectrometry. The approach uses high accuracy mass measurements from Fourier transform ion cyclotron resonance mass spectrometry (FTICR to validate peptide ‘accurate mass tags’ (AMTs produced by global protein enzymatic digestions for a specific organism, tissue or cell type from ‘potential mass tags’ tentatively identified using conventional tandem mass spectrometry (MS/MS. This provides the basis for subsequent measurements without the need for MS/ MS. High resolution capillary liquid chromatography separations combined with high sensitivity, and high resolution accurate FTICR measurements are shown to be capable of characterizing peptide mixtures of more than 105 components. The strategy has been initially demonstrated using the microorganisms Saccharomyces cerevisiae and Deinococcus radiodurans. Advantages of the approach include the high confidence of protein identification, its broad proteome coverage, high sensitivity, and the capability for stableisotope labeling methods for precise relative protein abundance measurements.

  16. Quantitative characterization of the fracture surface of Si single crystals by confocal microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Xin, Y.B.; Hsia, K.J.; Lange, D.A. [Univ. of Illinois, Urbana, IL (United States)

    1995-12-01

    Experiments are conducted to study the dislocation nucleation conditions at the crack tip in {l_brace}110{r_brace}<110> oriented Si single crystals. Specimens with surface cracks are first statically loaded at elevated temperatures for a prolonged period of time to initiate and move dislocations away from the crack tip, then cooled down to room temperature and loaded to fracture to measure the fracture toughness. Fractographic analysis of the fracture surfaces is performed. Distinct wavy patterns on the fracture surface at the initial cleavage crack front are observed, which is attributed to the existence of local mixed mode 1/mode 3 stresses resulting from the inhomogeneous dislocation activity. Confocal microscopy is employed to quantify the fracture surface roughness. The results show that the increase of fracture toughness is directly associated with the increased area of the rough surface, which is characterized by the roughness number or the fractal dimension increment. The results also demonstrate that dislocation nucleation can occur only at discrete sites. The spacing between these dislocation nucleation sources is of the order of 1 {micro}m. A simple model is developed for the relationship between the fracture toughness and the surface roughness parameters, which is in good agreement with the experimental results.

  17. Characterization of global yeast quantitative proteome data generated from the wild-type and glucose repression Saccharomyces cerevisiae strains: The comparison of two quantitative methods

    DEFF Research Database (Denmark)

    Usaite, Renata; Wohlschlegel, James; Venable, John D.;

    2008-01-01

    The quantitative proteomic analysis of complex protein mixtures is emerging as a technically challenging but viable systems-level approach for studying cellular function. This study presents a large-scale comparative analysis of protein abundances from yeast protein lysates derived from both wild......-type yeast and yeast strains lacking key components of the Snf1 kinase complex. Four different strains were grown under well-controlled chemostat conditions. Multidimensional protein identification technology followed by quantitation using either spectral counting or stable isotope labeling approaches...... labeling strategy. The stable isotope labeling based quantitative approach was found to be highly reproducible among biological replicates when complex protein mixtures containing small expression changes were analyzed. Where poor correlation between stable isotope labeling and spectral counting was found...

  18. TU-F-12A-02: Quantitative Characterization of Normal Bone Marrow Proliferative Activity with FLT PET/CT

    International Nuclear Information System (INIS)

    Purpose: [F-18]FLT PET is a tool for assessing health of bone marrow by evaluating its proliferative activity. This study establishes a baseline quantitative characterization of healthy marrow proliferation to aid in diagnosis of hematological disease. Methods: 31 patients (20 male, 11 female, 41–76 years) being treated for solid cancers with no history of hematological disease, osseous metastatic disease, or radiation therapy received pre-treatment FLT PET/CT scans. Total bone marrow was isolated from whole body FLT PET images by manually removing organs and applying a standardize uptake value (SUV) threshold of 1.0. Because adult marrow is concentrated in the axial skeleton, quantitative total bone marrow analysis (QTBMA) was used to isolate marrow in the lumbar spine, thoracic spine, sacrum, and pelvis for analysis. SUVmean, SUVmax, and SUVCV were used to quantify bone marrow proliferation. Correlations were explored between SUV and patient characteristics including age, weight, height, and BMI using the Spearman coefficient (ρ). Results: The population-averaged whole-skeleton SUVmean, SUVmax, and SUVCV were 3.0±0.6, 18.4±5.7, and 0.6±0.1, respectively. Uptake values in the axial skeleton were similar to the whole-skeleton demonstrated by SUVmean in the thoracic spine (3.6±0.6), lumbar spine (3.3±0.5), sacrum (3.0±0.6), and pelvis regions (2.8±0.5). Whole-skeleton SUVmax correlated with patient weight (ρ=0.47, p<0.01) and BMI (ρ=0.60, p<0.01), suggesting marrow activity is related to the body's burden. SUV measures in the thoracic spine, lumbar spine, sacrum, and pelvis were negatively correlated with age (ρ:−0.41 to −0.46, p≤0.02). These negative correlations reflect the fact that active marrow in the adult skeleton is localized in the axial skeleton and decreases with age. Conclusions: Normal bone marrow characterizations were determined using FLT

  19. QUANTITATIVE METHODS FOR RESERVOIR CHARACTERIZATION AND IMPROVED RECOVERY: APPLICATION TO HEAVY OIL SANDS

    Energy Technology Data Exchange (ETDEWEB)

    James W. Castle; Fred J. Molz; Ronald W. Falta; Cynthia L. Dinwiddie; Scott E. Brame; Robert A. Bridges

    2002-10-30

    Improved prediction of interwell reservoir heterogeneity has the potential to increase productivity and to reduce recovery cost for California's heavy oil sands, which contain approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley. This investigation involves application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation, particularly in heavy oil sands. The investigation was performed in collaboration with Chevron Production Company U.S.A. as an industrial partner, and incorporates data from the Temblor Formation in Chevron's West Coalinga Field. Observations of lateral variability and vertical sequences observed in Temblor Formation outcrops has led to a better understanding of reservoir geology in West Coalinga Field. Based on the characteristics of stratigraphic bounding surfaces in the outcrops, these surfaces were identified in the subsurface using cores and logs. The bounding surfaces were mapped and then used as reference horizons in the reservoir modeling. Facies groups and facies tracts were recognized from outcrops and cores of the Temblor Formation and were applied to defining the stratigraphic framework and facies architecture for building 3D geological models. The following facies tracts were recognized: incised valley, estuarine, tide- to wave-dominated shoreline, diatomite, and subtidal. A new minipermeameter probe, which has important advantages over previous methods of measuring outcrop permeability, was developed during this project. The device, which measures permeability at the distal end of a small drillhole, avoids surface weathering effects and provides a superior seal compared with previous methods for measuring outcrop permeability. The new probe was used successfully for obtaining a high-quality permeability data set from an outcrop in southern Utah

  20. Quantitative phase analysis and microstructure characterization of magnetite nanocrystals obtained by microwave assisted non-hydrolytic sol–gel synthesis

    International Nuclear Information System (INIS)

    An innovative preparation procedure, based on microwave assisted non-hydrolytic sol–gel synthesis, to obtain spherical magnetite nanoparticles was reported together with a detailed quantitative phase analysis and microstructure characterization of the synthetic products. The nanoparticle growth was analyzed as a function of the synthesis time and was described in terms of crystallization degree employing the Rietveld method on the magnetic nanostructured system for the determination of the amorphous content using hematite as internal standard. Product crystallinity increases as the microwave thermal treatment is increased and reaches very high percentages for synthesis times longer than 1 h. Microstructural evolution of nanocrystals was followed by the integral breadth methods to obtain information on the crystallite size-strain distribution. The results of diffraction line profile analysis were compared with nanoparticle grain distribution estimated by dimensional analysis of the transmission electron microscopy (TEM) images. A variation both in the average grain size and in the distribution of the coherently diffraction domains is evidenced, allowing to suppose a relationship between the two quantities. The traditional integral breadth methods have proven to be valid for a rapid assessment of the diffraction line broadening effects in the above-mentioned nanostructured systems and the basic assumption for the correct use of these methods are discussed as well. - Highlights: • Fe3O4 nanocrystals were obtained by MW-assisted non-hydrolytic sol–gel synthesis. • Quantitative phase analysis revealed that crystallinity up to 95% was reached. • The strategy of Rietveld refinements was discussed in details. • Dimensional analysis showed nanoparticles ranging from 4 to 8 nm. • Results of integral breadth methods were compared with microscopic analysis

  1. Quantitative phase analysis and microstructure characterization of magnetite nanocrystals obtained by microwave assisted non-hydrolytic sol–gel synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Sciancalepore, Corrado, E-mail: corrado.sciancalepore@unimore.it [Department of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, Via Pietro Vivarelli 10, 41100 Modena (Italy); Bondioli, Federica [Department of Industrial Engineering, University of Parma, Parco Area delle Scienze, 181/A, 43124 Parma (Italy); INSTM Consortium, Via G. Giusti 9, 51121 Firenze (Italy); Manfredini, Tiziano [Department of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, Via Pietro Vivarelli 10, 41100 Modena (Italy); INSTM Consortium, Via G. Giusti 9, 51121 Firenze (Italy); Gualtieri, Alessandro [Department of Chemical and Geological Science, University of Modena and Reggio Emilia, Via S. Eufemia 19, 41121 Modena Italy (Italy)

    2015-02-15

    An innovative preparation procedure, based on microwave assisted non-hydrolytic sol–gel synthesis, to obtain spherical magnetite nanoparticles was reported together with a detailed quantitative phase analysis and microstructure characterization of the synthetic products. The nanoparticle growth was analyzed as a function of the synthesis time and was described in terms of crystallization degree employing the Rietveld method on the magnetic nanostructured system for the determination of the amorphous content using hematite as internal standard. Product crystallinity increases as the microwave thermal treatment is increased and reaches very high percentages for synthesis times longer than 1 h. Microstructural evolution of nanocrystals was followed by the integral breadth methods to obtain information on the crystallite size-strain distribution. The results of diffraction line profile analysis were compared with nanoparticle grain distribution estimated by dimensional analysis of the transmission electron microscopy (TEM) images. A variation both in the average grain size and in the distribution of the coherently diffraction domains is evidenced, allowing to suppose a relationship between the two quantities. The traditional integral breadth methods have proven to be valid for a rapid assessment of the diffraction line broadening effects in the above-mentioned nanostructured systems and the basic assumption for the correct use of these methods are discussed as well. - Highlights: • Fe{sub 3}O{sub 4} nanocrystals were obtained by MW-assisted non-hydrolytic sol–gel synthesis. • Quantitative phase analysis revealed that crystallinity up to 95% was reached. • The strategy of Rietveld refinements was discussed in details. • Dimensional analysis showed nanoparticles ranging from 4 to 8 nm. • Results of integral breadth methods were compared with microscopic analysis.

  2. Quantitative characterization of conformational-specific protein-DNA binding using a dual-spectral interferometric imaging biosensor

    Science.gov (United States)

    Zhang, Xirui; Daaboul, George G.; Spuhler, Philipp S.; Dröge, Peter; Ünlü, M. Selim

    2016-03-01

    DNA-binding proteins play crucial roles in the maintenance and functions of the genome and yet, their specific binding mechanisms are not fully understood. Recently, it was discovered that DNA-binding proteins recognize specific binding sites to carry out their functions through an indirect readout mechanism by recognizing and capturing DNA conformational flexibility and deformation. High-throughput DNA microarray-based methods that provide large-scale protein-DNA binding information have shown effective and comprehensive analysis of protein-DNA binding affinities, but do not provide information of DNA conformational changes in specific protein-DNA complexes. Building on the high-throughput capability of DNA microarrays, we demonstrate a quantitative approach that simultaneously measures the amount of protein binding to DNA and nanometer-scale DNA conformational change induced by protein binding in a microarray format. Both measurements rely on spectral interferometry on a layered substrate using a single optical instrument in two distinct modalities. In the first modality, we quantitate the amount of binding of protein to surface-immobilized DNA in each DNA spot using a label-free spectral reflectivity technique that accurately measures the surface densities of protein and DNA accumulated on the substrate. In the second modality, for each DNA spot, we simultaneously measure DNA conformational change using a fluorescence vertical sectioning technique that determines average axial height of fluorophores tagged to specific nucleotides of the surface-immobilized DNA. The approach presented in this paper, when combined with current high-throughput DNA microarray-based technologies, has the potential to serve as a rapid and simple method for quantitative and large-scale characterization of conformational specific protein-DNA interactions.DNA-binding proteins play crucial roles in the maintenance and functions of the genome and yet, their specific binding mechanisms are

  3. Quantitative comparison between PGNAA measurements and MCNP calculations in view of the characterization of radioactive wastes in Germany and France

    Science.gov (United States)

    Mauerhofer, E.; Havenith, A.; Carasco, C.; Payan, E.; Kettler, J.; Ma, J. L.; Perot, B.

    2013-04-01

    The Forschungszentrum Jülich GmbH (FZJ), together with the Aachen University Rheinisch-Westfaelische Technische Hochschule (RWTH) and the French Alternative Energies and Atomic Energy Commission (CEA Cadarache) are involved in a cooperation aiming at characterizing toxic and reactive elements in radioactive waste packages by means of Prompt Gamma Neutron Activation Analysis (PGNAA) [1]. The French and German waste management agencies have indeed defined acceptability limits concerning these elements in view of their projected geological repositories. A first measurement campaign was performed in the new Prompt Gamma Neutron Activation Analysis (PGNAA) facility called MEDINA, at FZJ, to assess the capture gamma-ray signatures of some elements of interest in large samples up to waste drums with a volume of 200 liter. MEDINA is the acronym for Multi Element Detection based on Instrumental Neutron Activation. This paper presents MCNP calculations of the MEDINA facility and quantitative comparison between measurement and simulation. Passive gamma-ray spectra acquired with a high purity germanium detector and calibration sources are used to qualify the numerical model of the crystal. Active PGNAA spectra of a sodium chloride sample measured with MEDINA then allow for qualifying the global numerical model of the measurement cell. Chlorine indeed constitutes a usual reference with reliable capture gamma-ray production data. The goal is to characterize the entire simulation protocol (geometrical model, nuclear data, and postprocessing tools) which will be used for current measurement interpretation, extrapolation of the performances to other types of waste packages or other applications, as well as for the study of future PGNAA facilities.

  4. Quantitative comparison between PGNAA measurements and MCNP calculations in view of the characterization of radioactive wastes in Germany and France

    Energy Technology Data Exchange (ETDEWEB)

    Mauerhofer, E. [FZJ, Institute for Energy and Climate Research - Nuclear Waste Management and Reactor Safety, Wilhelm-Johnen-Strasse, D-52428 Juelich (Germany); Havenith, A.; Kettler, J. [RWTH Aachen University, Institute of Nuclear Fuel Cycle, Elisabethstrasse 16, D-52062 Aachen (Germany); Carasco, C.; Payan, E.; Ma, J. L.; Perot, B. [CEA, DEN, Cadarache, Nuclear Measurement Laboratory, F-13108 St Paul-lez-Durance (France)

    2013-04-19

    The Forschungszentrum Juelich GmbH (FZJ), together with the Aachen University Rheinisch-Westfaelische Technische Hochschule (RWTH) and the French Alternative Energies and Atomic Energy Commission (CEA Cadarache) are involved in a cooperation aiming at characterizing toxic and reactive elements in radioactive waste packages by means of Prompt Gamma Neutron Activation Analysis (PGNAA). The French and German waste management agencies have indeed defined acceptability limits concerning these elements in view of their projected geological repositories. A first measurement campaign was performed in the new Prompt Gamma Neutron Activation Analysis (PGNAA) facility called MEDINA, at FZJ, to assess the capture gamma-ray signatures of some elements of interest in large samples up to waste drums with a volume of 200 liter. MEDINA is the acronym for Multi Element Detection based on Instrumental Neutron Activation. This paper presents MCNP calculations of the MEDINA facility and quantitative comparison between measurement and simulation. Passive gamma-ray spectra acquired with a high purity germanium detector and calibration sources are used to qualify the numerical model of the crystal. Active PGNAA spectra of a sodium chloride sample measured with MEDINA then allow for qualifying the global numerical model of the measurement cell. Chlorine indeed constitutes a usual reference with reliable capture gamma-ray production data. The goal is to characterize the entire simulation protocol (geometrical model, nuclear data, and postprocessing tools) which will be used for current measurement interpretation, extrapolation of the performances to other types of waste packages or other applications, as well as for the study of future PGNAA facilities.

  5. Quantitative comparison between PGNAA measurements and MCNP calculations in view of the characterization of radioactive wastes in Germany and France

    International Nuclear Information System (INIS)

    The Forschungszentrum Jülich GmbH (FZJ), together with the Aachen University Rheinisch-Westfaelische Technische Hochschule (RWTH) and the French Alternative Energies and Atomic Energy Commission (CEA Cadarache) are involved in a cooperation aiming at characterizing toxic and reactive elements in radioactive waste packages by means of Prompt Gamma Neutron Activation Analysis (PGNAA). The French and German waste management agencies have indeed defined acceptability limits concerning these elements in view of their projected geological repositories. A first measurement campaign was performed in the new Prompt Gamma Neutron Activation Analysis (PGNAA) facility called MEDINA, at FZJ, to assess the capture gamma-ray signatures of some elements of interest in large samples up to waste drums with a volume of 200 liter. MEDINA is the acronym for Multi Element Detection based on Instrumental Neutron Activation. This paper presents MCNP calculations of the MEDINA facility and quantitative comparison between measurement and simulation. Passive gamma-ray spectra acquired with a high purity germanium detector and calibration sources are used to qualify the numerical model of the crystal. Active PGNAA spectra of a sodium chloride sample measured with MEDINA then allow for qualifying the global numerical model of the measurement cell. Chlorine indeed constitutes a usual reference with reliable capture gamma-ray production data. The goal is to characterize the entire simulation protocol (geometrical model, nuclear data, and postprocessing tools) which will be used for current measurement interpretation, extrapolation of the performances to other types of waste packages or other applications, as well as for the study of future PGNAA facilities.

  6. Quantitative Microanalysis with high Spatial Resolution: Application of FEG-DTEM XEDS Microanalysis to the Characterization of Complex Microstructures in Irradiated Low Alloy Steet

    Energy Technology Data Exchange (ETDEWEB)

    Williams, D.B., Watanabe, M. and Burke, M.G.

    2001-11-14

    To assist in the characterization of microstructural changes associated with irradiation damage in low alloy steels, the technique of quantitative x-ray mapping using a field emission gun scanning transmission electron microscope (FEG-STEM) equipped with an x-ray energy Dispersive spectrometer (XEDS) has been employed. Quantitative XEDS microanalyses of the matrix and grain boundaries of irradiated specimens have been compared with previous quantitative analyses obtained using 3D-Atom Probe Field-Ion Microscopy (3D-APFIM). In addition, the FEG-STEM XEDS maps obtained from the irradiated steel have revealed the presence of 2 to 3 nm Ni-enriched 'precipitates' in the matrix, which had previously been detected using 3D-APFIM. These quantitative FEG-STEM XEDS results represent the first direct and independent microchemical corroboration of the 3D-APFIM results showing ultra-fine irradiation-induced hardening features in low alloy steel.

  7. High-resolution gas chromatography/mas spectrometry method for characterization and quantitative analysis of ginkgolic acids in ginkgo biloba plants, extracts, and dietary supplements

    Science.gov (United States)

    A high resolution GC/MS with Selected Ion Monitor (SIM) method focusing on the characterization and quantitative analysis of ginkgolic acids (GAs) in Ginkgo biloba L. plant materials, extracts and commercial products was developed and validated. The method involved sample extraction with (1:1) meth...

  8. Adsorption of small biological molecules on silica from diluted aqueous solutions: Quantitative characterization and implications to the Bernal's hypothesis

    Science.gov (United States)

    Basiuk, Vladimir A.; Gromovoy, Taras Yu.; Khil'Chevskaya, Elena G.

    1995-08-01

    To describe quantitatively the adsorption of prebiotically important compounds of low molecular weight (amino acids, short linear peptides, cyclic dipeptides, the Krebs's cycle and other carboxylic acids, nucleosides and related phosphates) on silica surface from diluted neutral aqueous solutions, equilibrium constants (K) and free energies (-ΔG) of adsorption were determined from the retention values measured by means of high-performance liquid chromatography on a silica gel column and from the isotherms measured under static conditions. For most carboxylic acids (including amino acids and linear peptides) -ΔG values were negative and K0 and K>1 were found for most of them. Influence of the structure of α-substituent on the adsorbability is analyzed. A linear dependence of -ΔG on the number of aliphatic carbon atoms in a sorbate molecule was found for the series of aliphatic bifunctional amino acids, related dipeptides and 2,5-piperazinediones, as well as for the row from glycine to triglycyl glycine. The adsorption of nucleosides and their phosphates is characterized by much higherK and -ΔG values (of the order of 102 and 104, respectively). The adsorption data available from our work and literature are summarized and discussed with implications to the Bernal's hypothesis on the roles of solid surfaces in the prebiotic formation of biopolymers from monomeric ‘building blocks’.

  9. Quantitative characterization of crude oils and fuels in mineral substrates using reflectance spectroscopy: Implications for remote sensing

    Science.gov (United States)

    Scafutto, Rebecca Del'Papa Moreira; Souza Filho, Carlos Roberto de

    2016-08-01

    The near and shortwave infrared spectral reflectance properties of several mineral substrates impregnated with crude oils (°APIs 19.2, 27.5 and 43.2), diesel, gasoline and ethanol were measured and assembled in a spectral library. These data were examined using Principal Component Analysis (PCA) and Partial Least Squares (PLS) Regression. Unique and characteristic absorption features were identified in the mixtures, besides variations of the spectral signatures related to the compositional difference of the crude oils and fuels. These features were used for qualitative and quantitative determination of the contaminant impregnated in the substrates. Specific wavelengths, where key absorption bands occur, were used for the individual characterization of oils and fuels. The intensity of these features can be correlated to the abundance of the contaminant in the mixtures. Grain size and composition of the impregnated substrate directly influence the variation of the spectral signatures. PCA models applied to the spectral library proved able to differentiate the type and density of the hydrocarbons. The calibration models generated by PLS are robust, of high quality and can also be used to predict the concentration of oils and fuels in mixtures with mineral substrates. Such data and models are employable as a reference for classifying unknown samples of contaminated substrates. The results of this study have important implications for onshore exploration and environmental monitoring of oil and fuels leaks using proximal and far range multispectral, hyperspectral and ultraespectral remote sensing.

  10. Characterization of human metabolism and disposition of levo-tetrahydropalmatine: Qualitative and quantitative determination of oxidative and conjugated metabolites.

    Science.gov (United States)

    Xiao, Weibin; Shen, Guolin; Zhuang, Xiaomei; Ran, Xiaorong; Zhu, Mingshe; Li, Hua

    2016-09-01

    Levo-tetrahydropalmatine (l-THP) is a tetrahydroprotoberberine isoquinoline alkaloid and has been used as an analgesic agent in China for over 50 years. Recent studies revealed that l-THP was effective in the treatment of drug addiction. However, the plasma metabolic profile, mass balance and clearance pathways of l-THP in human remain unknown. In the present study, an analytical strategy was developed for qualitative and quantitative investigation of metabolism and disposition of l-THP in human. Detection and structural characterization of l-THP metabolites were performed using liquid chromatography-quadrupole time-of-flight mass spectrometry. Selected major metabolites in plasma, urine and feces determined by liquid chromatography with UV detection were further quantified using a triple quadruple mass spectrometry and reference standards. A total of 20 metabolites were identified, most of which were formed via demethylation, mono-hydroxylation, and glucuronidation and sulfonation of desmethyl metabolites. Five major metabolites accounted for over 10% of the parent drug concentration in plasma. Major urinary and fecal metabolites and the parent drug that were monitored for 72h accounted for 46.3% of the dose, while only 0.16% of the dose was the unchanged drug. Multiple demethylations followed by glucuronide and sulfate conjugations and renal excretion were the major drug clearance pathways of l-THP in human. PMID:27343900

  11. Quantitative characterization of the interfacial adhesion of Ni thin film on steel substrate: A compression-induced buckling delamination test

    Science.gov (United States)

    Zhu, W.; Zhou, Y. C.; Guo, J. W.; Yang, L.; Lu, C.

    2015-01-01

    A compression-induced buckling delamination test is employed to quantitatively characterize the interfacial adhesion of Ni thin film on steel substrate. It is shown that buckles initiate from edge flaws and surface morphologies exhibit symmetric, half-penny shapes. Taking the elastoplasticity of film and substrate into account, a three-dimensional finite element model for an edge flaw with the finite size is established to simulate the evolution of energy release rates and phase angles in the process of interfacial buckling-driven delamination. The results show that delamination propagates along both the straight side and curved front. The mode II delamination plays a dominant role in the process with a straight side whilst the curved front experiences almost the pure mode I. Based on the results of finite element analysis, a numerical model is developed to evaluate the interfacial energy release rate, which is in the range of 250-315 J/m2 with the corresponding phase angle from -41° to -66°. These results are in agreement with the available values determined by other testing methods, which confirms the effectiveness of the numerical model.

  12. Monte Carlo simulation approach for a quantitative characterization of the band edge in InGaN quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Kazlauskas, K.; Tamulatis, G.; Jursenas, S.; Zukauskas, A. [Institute of Materials Science and Applied Research, Vilnius University, Sauletekio 9, Build. III, 10222 Vilnius (Lithuania); Springis, M. [Institute of Solid State Physics, University of Latvia, Kengaraga iela 8, 1063 Riga (Latvia); Cheng, Yung-Chen; Wang, Hsiang-Chen; Huang, Chi-Feng; Yang, C.C. [Graduate Institute of Electro-Optical Engineering, National Taiwan University, 1 Roosevelt Road, Sec. 4, Taipei (Taiwan)

    2005-02-01

    Monte Carlo simulation approach based on exciton hopping through randomly distributed localized states is proposed for quantitative characterization of the band edge of In{sub x}Ga{sub 1-x}N/GaN multiple quantum wells with different indium content (x{approx}0.22-0.27). The band edge dynamics is investigated in the 10-300 K range by analyzing the measured S- and W-shaped temperature behavior of the photoluminescence peak position and linewidth, respectively. The simulation of the W-shaped temperature dependence using double-scaled potential profile model enabled us to estimate the scale of the potential fluctuations due to variation of indium content inside and among In-rich regions formed in InGaN alloy. Increased indium content in InGaN alloy resulted in an increase of the both scales of the potential fluctuations. Moreover, the temperature dependence of the exciton energy was reconstructed and compared with that obtained from the photoreflectance measurements. The density of localized states used in the simulations was in agreement with the photoluminescence excitation data. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Quantitative electron density characterization of soft tissue substitute plastic materials using grating-based x-ray phase-contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sarapata, A.; Chabior, M.; Zanette, I.; Pfeiffer, F. [Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Cozzini, C.; Sperl, J. I.; Bequé, D. [GE Global Research, 85748 Garching (Germany); Langner, O.; Coman, J. [QRM GmbH, Möhrendorf (Germany); Ruiz-Yaniz, M. [Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); European Synchrotron Radiation Facility, Grenoble (France)

    2014-10-15

    Many scientific research areas rely on accurate electron density characterization of various materials. For instance in X-ray optics and radiation therapy, there is a need for a fast and reliable technique to quantitatively characterize samples for electron density. We present how a precise measurement of electron density can be performed using an X-ray phase-contrast grating interferometer in a radiographic mode of a homogenous sample in a controlled geometry. A batch of various plastic materials was characterized quantitatively and compared with calculated results. We found that the measured electron densities closely match theoretical values. The technique yields comparable results between a monochromatic and a polychromatic X-ray source. Measured electron densities can be further used to design dedicated X-ray phase contrast phantoms and the additional information on small angle scattering should be taken into account in order to exclude unsuitable materials.

  14. Quantitative electron density characterization of soft tissue substitute plastic materials using grating-based x-ray phase-contrast imaging

    Science.gov (United States)

    Sarapata, A.; Chabior, M.; Cozzini, C.; Sperl, J. I.; Bequé, D.; Langner, O.; Coman, J.; Zanette, I.; Ruiz-Yaniz, M.; Pfeiffer, F.

    2014-10-01

    Many scientific research areas rely on accurate electron density characterization of various materials. For instance in X-ray optics and radiation therapy, there is a need for a fast and reliable technique to quantitatively characterize samples for electron density. We present how a precise measurement of electron density can be performed using an X-ray phase-contrast grating interferometer in a radiographic mode of a homogenous sample in a controlled geometry. A batch of various plastic materials was characterized quantitatively and compared with calculated results. We found that the measured electron densities closely match theoretical values. The technique yields comparable results between a monochromatic and a polychromatic X-ray source. Measured electron densities can be further used to design dedicated X-ray phase contrast phantoms and the additional information on small angle scattering should be taken into account in order to exclude unsuitable materials.

  15. Wax and cutin mutants of Arabidopsis: Quantitative characterization of the cuticular transport barrier in relation to chemical composition.

    Science.gov (United States)

    Sadler, Christina; Schroll, Bettina; Zeisler, Viktoria; Waßmann, Friedrich; Franke, Rochus; Schreiber, Lukas

    2016-09-01

    Using (14)C-labeled epoxiconazole as a tracer, cuticular permeability of Arabidopsis thaliana leaves was quantitatively measured in order to compare different wax and cutin mutants (wax2, cut1, cer5, att1, bdg, shn3 and shn1) to the corresponding wild types (Col-0 and Ws). Mutants were characterized by decreases or increases in wax and/or cutin amounts. Permeances [ms(-1)] of Arabidopsis cuticles either increased in the mutants compared to wild type or were not affected. Thus, genetic changes in wax and cutin biosynthesis in some of the investigated Arabidopsis mutants obviously impaired the coordinated cutin and wax deposition at the outer leaf epidermal cell wall. As a consequence, barrier properties of cuticles were significantly decreased. However, increasing cutin and wax amounts by genetic modifications, did not automatically lead to improved cuticular barrier properties. As an alternative approach to the radioactive transport assay, changes in chlorophyll fluorescence were monitored after foliar application of metribuzine, an herbicide inhibiting electron transport in chloroplasts. Since both, half-times of photosynthesis inhibition as well as times of complete inhibition, in fact correlated with (14)C-epoxiconazole permeances, different rates of decline of photosynthetic yield between mutants and wild type must be a function of foliar uptake of the herbicide across the cuticle. Thus, monitoring changes in chlorophyll fluorescence, instead of conducting radioactive transport assays, represents an easy-to-handle and fast alternative evaluating cuticular barrier properties of different genotypes. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.

  16. Implementation of Contraction to Electrophysiological Ventricular Myocyte Models, and Their Quantitative Characterization via Post-Extrasystolic Potentiation.

    Directory of Open Access Journals (Sweden)

    Yanyan Claire Ji

    Full Text Available Heart failure (HF affects over 5 million Americans and is characterized by impairment of cellular cardiac contractile function resulting in reduced ejection fraction in patients. Electrical stimulation such as cardiac resynchronization therapy (CRT and cardiac contractility modulation (CCM have shown some success in treating patients with HF. Computer simulations have the potential to help improve such therapy (e.g. suggest optimal lead placement as well as provide insight into the underlying mechanisms which could be beneficial. However, these myocyte models require a quantitatively accurate excitation-contraction coupling such that the electrical and contraction predictions are correct. While currently there are close to a hundred models describing the detailed electrophysiology of cardiac cells, the majority of cell models do not include the equations to reproduce contractile force or they have been added ad hoc. Here we present a systematic methodology to couple first generation contraction models into electrophysiological models via intracellular calcium and then compare the resulting model predictions to experimental data. This is done by using a post-extrasystolic pacing protocol, which captures essential dynamics of contractile forces. We found that modeling the dynamic intracellular calcium buffers is necessary in order to reproduce the experimental data. Furthermore, we demonstrate that in models the mechanism of the post-extrasystolic potentiation is highly dependent on the calcium released from the Sarcoplasmic Reticulum. Overall this study provides new insights into both specific and general determinants of cellular contractile force and provides a framework for incorporating contraction into electrophysiological models, both of which will be necessary to develop reliable simulations to optimize electrical therapies for HF.

  17. Implementation of Contraction to Electrophysiological Ventricular Myocyte Models, and Their Quantitative Characterization via Post-Extrasystolic Potentiation.

    Science.gov (United States)

    Ji, Yanyan Claire; Gray, Richard A; Fenton, Flavio H

    2015-01-01

    Heart failure (HF) affects over 5 million Americans and is characterized by impairment of cellular cardiac contractile function resulting in reduced ejection fraction in patients. Electrical stimulation such as cardiac resynchronization therapy (CRT) and cardiac contractility modulation (CCM) have shown some success in treating patients with HF. Computer simulations have the potential to help improve such therapy (e.g. suggest optimal lead placement) as well as provide insight into the underlying mechanisms which could be beneficial. However, these myocyte models require a quantitatively accurate excitation-contraction coupling such that the electrical and contraction predictions are correct. While currently there are close to a hundred models describing the detailed electrophysiology of cardiac cells, the majority of cell models do not include the equations to reproduce contractile force or they have been added ad hoc. Here we present a systematic methodology to couple first generation contraction models into electrophysiological models via intracellular calcium and then compare the resulting model predictions to experimental data. This is done by using a post-extrasystolic pacing protocol, which captures essential dynamics of contractile forces. We found that modeling the dynamic intracellular calcium buffers is necessary in order to reproduce the experimental data. Furthermore, we demonstrate that in models the mechanism of the post-extrasystolic potentiation is highly dependent on the calcium released from the Sarcoplasmic Reticulum. Overall this study provides new insights into both specific and general determinants of cellular contractile force and provides a framework for incorporating contraction into electrophysiological models, both of which will be necessary to develop reliable simulations to optimize electrical therapies for HF. PMID:26317204

  18. A case of dialysis-related amyloidosis of the hip and cervical spine: imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gyung Kyu; Kang, Ik Won; Min, Seon Jung; Cho, Seong Whi; Kim, Seok Woo; Jang, Woo Young [Hallym University College of Medicine, Chuncheon (Korea, Republic of); Lee, Seon Joo [Inje University College of Medicine, Seoul (Korea, Republic of); Suh, Kyung Jin [Dankook University College of Medicine, Busan Paik Hospital, Busan (Korea, Republic of)

    2006-05-15

    Dialysis-related amyloidosis is a complication of long-term hemodialysis and it is characterized by the accumulation of {beta} 2-microglobulin in the osteoarticular structures. We describe here the imaging findings of a case of dialysis-related amyloidosis involving the hip and cervical spine in a 62-year-old woman who received long-term dialysis. We focus here on the CT and MR imaging findings of the cervical spine and we include a review of the relevant literatures.

  19. Characterization of membrane protein interactions in plasma membrane derived vesicles with quantitative imaging Förster resonance energy transfer.

    Science.gov (United States)

    Sarabipour, Sarvenaz; Del Piccolo, Nuala; Hristova, Kalina

    2015-08-18

    Here we describe an experimental tool, termed quantitative imaging Förster resonance energy transfer (QI-FRET), that enables the quantitative characterization of membrane protein interactions. The QI-FRET methodology allows us to acquire binding curves and calculate association constants for complex membrane proteins in the native plasma membrane environment. The method utilizes FRET detection, and thus requires that the proteins of interest are labeled with florescent proteins, either FRET donors or FRET acceptors. Since plasma membranes of cells have complex topologies precluding the acquisition of two-dimensional binding curves, the FRET measurements are performed in plasma membrane derived vesicles that bud off cells as a result of chemical or osmotic stress. The results overviewed here are acquired in vesicles produced with an osmotic vesiculation buffer developed in our laboratory, which does not utilize harsh chemicals. The concentrations of the donor-labeled and the acceptor-labeled proteins are determined, along with the FRET efficiencies, in each vesicle. The experiments utilize transient transfection, such that a wide variety of concentrations is sampled. Then, data from hundreds of vesicles are combined to yield dimerization curves. Here we discuss recent findings about the dimerization of receptor tyrosine kinases (RTKs), membrane proteins that control cell growth and differentiation via lateral dimerization in the plasma membrane. We focus on the dimerization of fibroblast growth factor receptor 3 (FGFR3), a RTK that plays a critically important role in skeletal development. We study the role of different FGFR3 domains in FGFR3 dimerization in the absence of ligand, and we show that FGFR3 extracellular domains inhibit unliganded dimerization, while contacts between the juxtamembrane domains, which connect the transmembrane domains to the kinase domains, stabilize the unliganded FGFR3 dimers. Since FGFR3 has been documented to harbor many pathogenic

  20. Sulfonium Ion Derivatization, Isobaric Stable Isotope Labeling and Data Dependent CID- and ETD-MS/MS for Enhanced Phosphopeptide Quantitation, Identification and Phosphorylation Site Characterization

    OpenAIRE

    Lu, Yali; Zhou, Xiao; Stemmer, Paul M.; Reid, Gavin E.

    2011-01-01

    An amine specific peptide derivatization strategy involving the use of novel isobaric stable isotope encoded ‘fixed charge’ sulfonium ion reagents, coupled with an analysis strategy employing capillary HPLC, ESI-MS, and automated data dependent ion trap CID-MS/MS, -MS3, and/or ETD-MS/MS, has been developed for the improved quantitative analysis of protein phosphorylation, and for identification and characterization of their site(s) of modification. Derivatization of 50 synthetic phosphopeptid...

  1. A quantitative method to characterize the Al_{4}C_{3}-formed interfacial reaction : the case study of MWCNT/Al composites

    OpenAIRE

    Yan, Laipeng; Tan, Zhanqiu; Ji, Gang; Li, Zhiqiang; Fan, Genlian; Schryvers, D.; Shan, Aidang; Zhang, Di

    2016-01-01

    Abstract: The Al4C3-formed interfacial reaction plays an important role in tuning the mechanical and thermal properties of carbon/aluminum (C/Al) composites reinforced with carbonaceous materials such as multi-wall carbon nanotube (MWCNT) and graphene nanosheet. In terms of the hydrolysis nature of Al4C3, an electrochemical dissolution method was developed to quantitatively characterize the extent of C/Al interfacial reaction, which involves dissolving the composite samples in alkaline soluti...

  2. Optical characterization of red blood cells from individuals with sickle cell trait and disease in Tanzania using quantitative phase imaging

    Science.gov (United States)

    Jung, Jaehwang; Matemba, Lucas E.; Lee, Kyeoreh; Kazyoba, Paul E.; Yoon, Jonghee; Massaga, Julius J.; Kim, Kyoohyun; Kim, Dong-Jin; Park, Yongkeun

    2016-08-01

    Sickle cell disease (SCD) is common across Sub-Saharan Africa. However, the investigation of SCD in this area has been significantly limited mainly due to the lack of research facilities and skilled personnel. Here, we present optical measurements of individual red blood cells from healthy individuals and individuals with SCD and sickle cell trait in Tanzania using the quantitative phase imaging technique. By employing a quantitative phase imaging unit, an existing microscope in a clinic is transformed into a powerful quantitative phase microscope providing measurements on the morphological, biochemical, and biomechanical properties of individual cells. The present approach will open up new opportunities for cost-effective investigation and diagnosis of several diseases in low resource environments.

  3. Optical characterization of red blood cells from individuals with sickle cell trait and disease in Tanzania using quantitative phase imaging.

    Science.gov (United States)

    Jung, JaeHwang; Matemba, Lucas E; Lee, KyeoReh; Kazyoba, Paul E; Yoon, Jonghee; Massaga, Julius J; Kim, Kyoohyun; Kim, Dong-Jin; Park, YongKeun

    2016-01-01

    Sickle cell disease (SCD) is common across Sub-Saharan Africa. However, the investigation of SCD in this area has been significantly limited mainly due to the lack of research facilities and skilled personnel. Here, we present optical measurements of individual red blood cells from healthy individuals and individuals with SCD and sickle cell trait in Tanzania using the quantitative phase imaging technique. By employing a quantitative phase imaging unit, an existing microscope in a clinic is transformed into a powerful quantitative phase microscope providing measurements on the morphological, biochemical, and biomechanical properties of individual cells. The present approach will open up new opportunities for cost-effective investigation and diagnosis of several diseases in low resource environments. PMID:27546097

  4. Optical characterization of red blood cells from individuals with sickle cell trait and disease in Tanzania using quantitative phase imaging

    CERN Document Server

    Jung, JaeHwang; Lee, KyeoReh; Kazyoba, Paul E; Yoon, Jonghee; Massaga, Julius J; Kim, Kyoohyun; Kim, Dong-Jin; Park, YongKeun

    2016-01-01

    Sickle cell disease (SCD) is common across Sub-Saharan Africa. However, the investigation of SCD in this area has been significantly limited mainly due to the lack of research facilities and skilled personnel. Here, we present optical measurements of individual red blood cells (RBCs) from healthy individuals and individuals with SCD and sickle cell trait in Tanzania using the quantitative phase imaging technique. By employing a quantitative phase imaging unit (QPIU), an existing microscope in a clinic is transformed into a powerful quantitative phase microscope providing measurements on the morphological, biochemical, and biomechanical properties of individual cells. The present approach will open up new opportunities for cost-effective investigation and diagnosis of several diseases in low resource environments.

  5. Multimodal label-free growth and morphology characterization of different cell types in a single culture with quantitative digital holographic phase microscopy

    Science.gov (United States)

    Kemper, Björn; Wibbeling, Jana; Kastl, Lena; Schnekenburger, Jürgen; Ketelhut, Steffi

    2015-03-01

    For the analysis of the impact of pharmaceuticals or pathogens on different cellular phenotypes under identical measurement conditions and to analyze interactions between different cellular specimens a minimally-invasive quantitative observation of different cell types in a single culture is of particular interest. Digital holographic microscopy (DHM), a var-iant of quantitative phase microscopy (QPM), provides high resolution detection of optical path length changes that is suitable for stain-free minimally-invasive live cell analysis. Due to low light intensities for object illumination, QPM minimizes the interaction with the sample and has been demonstrated in particular to be suitable for long-term time-lapse investigations, e.g., for the detection of cell morphology alterations due to drugs and toxins. Furthermore, QPM has been demonstrated to be a versatile tool for the quantification of cellular growth and motility. Thus, we studied the feasibility of QPM for the analysis of mixed cell cultures and explored if quantitative phase images provide sufficient information to distinguish between different cell types and to extract cell specific parameters. For the experiments quantitative phase imaging with DHM was utilized. Mixed cell cultures with different cell types were observed with quantitative DHM phase contrast up to 35 h. The obtained series of quantitative phase images were evaluated by adapted algorithms for image segmentation. From the segmented images the area covered by the cells, the cellular dry mass and the mean cell thickness were calculated and used in the further analysis as parameters to quantify the reliability of the measurement principle. The obtained results demonstrate that it is possible to characterize the growth of cell types with different mor-phology features separately in a single culture.

  6. Characterization of human myotubes from type 2 diabetic and non-diabetic subjects using complementary quantitative mass spectrometric methods

    DEFF Research Database (Denmark)

    Thingholm, Tine E; Bak, Steffen; Beck-Nielsen, Henning;

    2011-01-01

    2 diabetes. Several abnormalities have been identified in skeletal muscle from type 2 diabetic subjects, however, the exact molecular mechanisms leading to the diabetic phenotype has still not been found. Here we present a large-scale study in which we combine a quantitative proteomic discovery...... strategy using iTRAQ and a label-free study with a targeted quantitative proteomic approach using selected reaction monitoring (SRM) to identify, quantify and validate changes in protein abundance between human myotubes obtained from non-diabetic lean, non-diabetic obese and type 2 diabetic subjects...

  7. Quantitative energy-dispersive electron probe X-ray microanalysis for single-particle analysis and its application for characterizing atmospheric aerosol particles

    Indian Academy of Sciences (India)

    Shila Maskey; Chul-Un Ro

    2011-02-01

    An energy-dispersive electron probe X-ray microanalysis (ED-EPMA) technique using an energy-dispersive X-ray detector with an ultra-thin window, designated as low-Z particle EPMA, has been developed. The low-Z particle EPMA allows the quantitative determination of concentrations of low-Z elements such as C, N and O, as well as higher-Z elements that can be analysed by conventional ED-EPMA. The quantitative determination of low-Z elements (using full Monte Carlo simulations, from the electron impact to the X-ray detection) in individual particles has improved the applicability of single-particle analysis, especially in atmospheric environmental aerosol research; many environmentally important atmospheric particles, e.g. sulphates, nitrates, ammonium and carbonaceous particles, contain low-Z elements. To demonstrate its practical applicability, the application of the low-Z particle EPMA for the characterization of Asian Dust, urban and subway aerosol particles is shown herein. In addition, it is demonstrated that the Monte Carlo calculation can also be applied in a quantitative single-particle analysis using transmission electron microscopy (TEM) coupled with energy-dispersive X-ray spectrometry (EDX), showing that the technique is useful and reliable for the characterization of submicron aerosol particles

  8. Quantitative characterization of phase separation in the photoactive layer of polymer solar cells by the phase image of atomic force microscopy

    International Nuclear Information System (INIS)

    We have quantitatively characterized the phase separation of poly(3-hexylthiophene) (P3HT):C61-butyric acid methyl ester (PCBM) blend films and studied the effect of phase separation of photoactive layer on the performance of polymer solar cells. A mixed solvent of dichlorobenzene and chlorobenzene was adopted to prepare the P3HT:PCBM blend films, and a series of blend films with different morphologies were obtained by adjusting both the volume ratio of dichlorobenzene to chlorobenzene and the solvent annealing time. The surface morphology and phase distribution were measured by atomic force microscopy (AFM). The interface length between the domains of donor and acceptor, which is extracted from the AFM phase image of blend film, was used to quantitatively characterize the phase separation of photoactive layer. It was found that the short-circuit current density (JSC) of bulk heterojunction solar cells is proportional to the interfacial area of two phases, while it has a negligible effect on the open-circuit voltage. These results indicate that the larger interfacial area of donor and acceptor phases is beneficial to the exciton dissociation and carrier transport resulting in a significant increase of JSC and power conversion efficiency. - Highlights: • Phase separation of photoactive layers in polymer solar cells was evaluated quantitatively. • Interface contours between the donor and acceptor were extracted from AFM phase images. • Effects of phase separation on polymer solar cell performance were investigated. • The interface area mainly influences short-circuit current of the polymer solar cells

  9. Cellular distribution of ferric iron, ferritin, transferrin and divalent metal transporter 1 (DMT1) in substantia nigra and basal ganglia of normal and β2-microglobulin deficient mouse brain

    DEFF Research Database (Denmark)

    Moos, Torben; Trinder, D.; Morgan, E.H.

    2000-01-01

    beta-2-microglobulin, blood-brain barrier, gene knock out, iron, neurodegenerative disorders, oxidative damage, subthalamic nucleus......beta-2-microglobulin, blood-brain barrier, gene knock out, iron, neurodegenerative disorders, oxidative damage, subthalamic nucleus...

  10. Vortex flow during early and late left ventricular filling in normal subjects: quantitative characterization using retrospectively-gated 4D flow cardiovascular magnetic resonance and three-dimensional vortex core analysis

    NARCIS (Netherlands)

    Elbaz, M.S.M.; Calkoen, E.E.; Westenberg, J.J.M.; Lelieveldt, B.P.F.; Roest, A.A.W.; Van der Geest, R.J.

    2014-01-01

    Background LV diastolic vortex formation has been suggested to critically contribute to efficient blood pumping function, while altered vortex formation has been associated with LV pathologies. Therefore, quantitative characterization of vortex flow might provide a novel objective tool for evaluatin

  11. Quantitative Characterization of Gold Nanoparticles by Field-Flow Fractionation Coupled Online with Light Scattering Detection and Inductively Coupled Plasma Mass Spectrometry

    DEFF Research Database (Denmark)

    Schmidt, Bjørn; Löschner, Katrin; Hadrup, Niels;

    2011-01-01

    An analytical platform coupling asymmetric flow field-flow fractionation (AF4) with multiangle light scattering (MALS), dynamic light scattering (DLS), and inductively coupled plasma mass spectrometry (ICPMS) was established and used for separation and quantitative determination of size and mass...... was found to be a major cause for incomplete recoveries. The lower limit of detection (LOD) ranged between 0.02 ng Au and 0.4 ng Au, with increasing LOD by increasing nanoparticle diameter. The analytical platform was applied to characterization of Au NPs in livers of rats, which were dosed with 10 nm, 60...

  12. Genetic and Physiological Characterization of Two Clusters of Quantitative Trait Loci Associated With Seed Dormancy and Plant Height in Rice

    OpenAIRE

    Ye, Heng; Beighley, Donn H.; Feng, Jiuhuan; Gu, Xing-You

    2013-01-01

    Seed dormancy and plant height have been well-studied in plant genetics, but their relatedness and shared regulatory mechanisms in natural variants remain unclear. The introgression of chromosomal segments from weedy into cultivated rice (Oryza sativa) prompted the detection of two clusters (qSD1-2/qPH1 and qSD7-2/qPH7) of quantitative trait loci both associated with seed dormancy and plant height. Together, these two clusters accounted for >96% of the variances for plant height and ~71% of t...

  13. Quantitative characterization of phase separation in the photoactive layer of polymer solar cells by the phase image of atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Gao, H.L.; Zhang, X.W., E-mail: xwzhang@semi.ac.cn; Meng, J.H.; Yin, Z.G.; Zhang, L.Q.; Wu, J.L.; Liu, X.

    2015-02-02

    We have quantitatively characterized the phase separation of poly(3-hexylthiophene) (P3HT):C61-butyric acid methyl ester (PCBM) blend films and studied the effect of phase separation of photoactive layer on the performance of polymer solar cells. A mixed solvent of dichlorobenzene and chlorobenzene was adopted to prepare the P3HT:PCBM blend films, and a series of blend films with different morphologies were obtained by adjusting both the volume ratio of dichlorobenzene to chlorobenzene and the solvent annealing time. The surface morphology and phase distribution were measured by atomic force microscopy (AFM). The interface length between the domains of donor and acceptor, which is extracted from the AFM phase image of blend film, was used to quantitatively characterize the phase separation of photoactive layer. It was found that the short-circuit current density (J{sub SC}) of bulk heterojunction solar cells is proportional to the interfacial area of two phases, while it has a negligible effect on the open-circuit voltage. These results indicate that the larger interfacial area of donor and acceptor phases is beneficial to the exciton dissociation and carrier transport resulting in a significant increase of J{sub SC} and power conversion efficiency. - Highlights: • Phase separation of photoactive layers in polymer solar cells was evaluated quantitatively. • Interface contours between the donor and acceptor were extracted from AFM phase images. • Effects of phase separation on polymer solar cell performance were investigated. • The interface area mainly influences short-circuit current of the polymer solar cells.

  14. Characterization of the human myocardial proteome in inflammatory dilated cardiomyopathy by label-free quantitative shotgun proteomics of heart biopsies

    NARCIS (Netherlands)

    Hammer, E.; Goritzka, M.; Ameling, S.; Darm, K.; Steil, L.; Klingel, K.; Trimpert, C.; Herda, L.R.; Dorr, M.; Kroemer, H.K.; Kandolf, R.; Staudt, A.; Felix, S.B.; Volker, U.

    2011-01-01

    Dilated cardiomyopathy (DCM) is characterized by contractile dysfunction leading to heart failure. The molecular changes in the human heart associated with this disease have so far mostly been addressed at the gene expression level and only a few studies have analyzed global changes in the myocardia

  15. Quantitative sampling and analysis of trace elements in ambient air: impactor characterization and Synchrotron-XRF mass calibration

    Directory of Open Access Journals (Sweden)

    A. Richard

    2010-06-01

    Full Text Available Identification of trace elements in ambient air can add substantial information to pollution source apportionment studies, although they do not contribute significantly to emissions in terms of mass. A method for quantitative size and time-resolved trace element evaluation in ambient aerosols with a rotating drum impactor and synchrotron radiation based X-ray fluorescence is presented. The impactor collection efficiency curves and size segregation characteristics were investigated in an experiment with oil and salt particles. Cutoff diameters were determined through the ratio of size distributions measured with two particles sizers. Furthermore, an external calibration technique to empirically link fluorescence intensities to ambient concentrations was developed. Solutions of elemental standards were applied with an ink-jet printer on thin films and area concentrations were subsequently evaluated with external wet chemical methods. These customized and reusable reference standards enable quantification of different data sets analyzed under varying experimental conditions.

  16. Quantitative sampling and analysis of trace elements in atmospheric aerosols: impactor characterization and Synchrotron-XRF mass calibration

    Directory of Open Access Journals (Sweden)

    A. Richard

    2010-10-01

    Full Text Available Identification of trace elements in ambient air can add substantial information to pollution source apportionment studies, although they do not contribute significantly to emissions in terms of mass. A method for quantitative size and time-resolved trace element evaluation in ambient aerosols with a rotating drum impactor and synchrotron radiation based X-ray fluorescence is presented. The impactor collection efficiency curves and size segregation characteristics were investigated in an experiment with oil and salt particles. Cutoff diameters were determined through the ratio of size distributions measured with two particle sizers. Furthermore, an external calibration technique to empirically link fluorescence intensities to ambient concentrations was developed. Solutions of elemental standards were applied with an ink-jet printer on thin films and area concentrations were subsequently evaluated with external wet chemical methods. These customized and reusable reference standards enable quantification of different data sets analyzed under varying experimental conditions.

  17. An Integrated Quantitative Methodology to Longitudinally Characterize Complex Dynamic Processes Associated with Ovarian Aging and the Menopausal Transition

    Directory of Open Access Journals (Sweden)

    Huiyong Zheng

    2011-06-01

    Full Text Available An integrative methodology is developed to characterize the complex patterns of change in highly variable dynamic biological processes. The method permits estimatation of the population mean profile, multiple change points and length of time-windows defined by any two change points of interest using a semi-/non-parametric stochastic mixed effect model and a Bayesian Modeling Average (BMA approach to account for model uncertainty. It also allows estimation of the mean rate of change of sub-processes by fitting piecewise linear mixed effect models. The methodology is applied to characterize the stages of female ovarian aging and the menopausal transition defined by hormone measures of estradiol (E2 and follicle stimulating hormone (FSH from two large-scale epidemiological studies with community-based longitudinal designs and ethnic diversity.

  18. Quantitative Characterization of Phosphor Detector for Fusion Plasmas; Caracterizacion Cuantitativa de Detectores Luminiscentes para Plasmas de Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Baciero, A.; Zurro, B.; McCarthy, K. J.

    2004-07-01

    Experiments made to characterize phosphor screens with application as broadband radiation detectors, are described. Several radiation sources, covering the spectral range between the ultraviolet and X ray, were used. In addition, details are given of three original phosphor-screen-based detectors that were designed for use as broadband detectors in magnetically confined fusion devices. The first measurements obtained with these detectors in plasmas created in the TJ-II stellarator device are presented together with the analysis performed. (Author)

  19. Quantitative MR characterization of disease activity in the knee in children with juvenile idiopathic arthritis: a longitudinal pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Workie, Dagnachew W. [University of Cincinnati, Department of Physics, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Cincinnati, OH (United States); Graham, T.B. [Cincinnati Children' s Hospital Medical Center, Division of Rheumatology, Cincinnati, OH (United States); Laor, Tal; Racadio, Judy M. [Cincinnati Children' s Hospital Medical Center, Department of Pediatrics, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Rajagopal, Akila; O' Brien, Kendall J.; Bommer, Wendy A. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Cincinnati, OH (United States); Shire, Norah J. [University of Cincinnati, Division of Epidemiology and Biostatistics, Cincinnati, OH (United States); University of Cincinnati, Division of Digestive Diseases, Cincinnati, OH (United States); Dardzinski, Bernard J. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Pediatrics, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2007-06-15

    The development of a quantifiable and noninvasive method of monitoring disease activity and response to therapy is vital for arthritis management. The purpose of this study was to investigate the utility of quantitative dynamic contrast-enhanced MRI (DCE-MRI) based on pharmacokinetic (PK) modeling to evaluate disease activity in the knee and correlate the results with the clinical assessment in children with juvenile idiopathic arthritis (JIA). A group of 17 children with JIA underwent longitudinal clinical and laboratory assessment and DCE-MRI of the knee at enrollment, 3 months, and 12 months. A PK model was employed using MRI signal enhancement data to give three parameters, K{sup trans} ' (min{sup -1}), k{sub ep} (min{sup -1}), and V{sub p} ' and to calculate synovial volume. The PK parameters, synovial volumes, and clinical and laboratory assessments in most children were significantly decreased (P < 0.05) at 12 months when compared to the enrollment values. There was excellent correlation between the PK and synovial volume and the clinical and laboratory assessments. Differences in MR and clinical parameter values in individual subjects illustrate persistent synovitis when in clinical remission. A decrease in PK parameter values obtained from DCE-MRI in children with JIA likely reflects diminution of disease activity. This technique may be used as an objective follow-up measure of therapeutic efficacy in patients with JIA. MR imaging can detect persistent synovitis in patients considered to be in clinical remission. (orig.)

  20. Roles of biologic breast tissue composition and quantitative image analysis of mammographic images in breast tumor characterization

    Science.gov (United States)

    Drukker, Karen; Giger, Maryellen L.; Duewer, Fred; Malkov, Serghei; Flowers, Christopher I.; Joe, Bonnie; Kerlikowske, Karla; Drukteinis, Jennifer S.; Shepherd, John

    2014-03-01

    Purpose. Investigate whether knowledge of the biologic image composition of mammographic lesions provides imagebased biomarkers above and beyond those obtainable from quantitative image analysis (QIA) of X-ray mammography. Methods. The dataset consisted of 45 in vivo breast lesions imaged with the novel 3-component breast (3CB) imaging technique based on dual-energy mammography (15 malignant, 30 benign diagnoses). The 3CB composition measures of water, lipid, and protein thicknesses were assessed and mathematical descriptors, `3CB features', were obtained for the lesions and their periphery. The raw low-energy mammographic images were analyzed with an established in-house QIA method obtaining `QIA features' describing morphology and texture. We investigated the correlation within the `3CB features', within the `QIA features', and between the two. In addition, the merit of individual features in the distinction between malignant and benign lesions was assessed. Results. Whereas many descriptors within the `3CB features' and `QIA features' were, often by design, highly correlated, correlation between descriptors of the two feature groups was much weaker (maximum absolute correlation coefficient 0.58, pappeared equally well-suited for the distinction between malignant and benign lesions, with maximum area under the ROC curve 0.71 for a protein feature (3CB) and 0.71 for a texture feature (QIA). Conclusions. In this pilot study analyzing the new 3CB imaging modality, knowledge of breast tissue composition appeared additive in combination with existing mammographic QIA methods for the distinction between benign and malignant lesions.

  1. Characterization of individual aerosol particles collected during a haze episode in Incheon, Korea using the quantitative ED-EPMA technique

    Directory of Open Access Journals (Sweden)

    H. Geng

    2010-11-01

    Full Text Available Haze is an atmospheric phenomenon that leads to low visibility, and is mostly due to elevated levels of fine particulate matter. It can have effects on cloud formation, public health, agriculture, and even the global climate. Although urban haze has been increasing in occurrence over the past several years over the Seoul-Incheon metropolis, Korea, studies of the morphology and chemical composition of ambient aerosol particles by single-particle analysis during haze episodes have rarely been conducted. Herein, a quantitative energy-dispersive electron probe microanalysis (ED-EPMA, called low-Z particle EPMA, was used to analyze individual aerosol particles collected in Incheon, Korea on 13–18 October 2008 (a typical haze episode occurred from 15 to 18 October. Overall, 3600 particles in 12 aerosol samples collected on haze and non-haze days were measured by low-Z particle EPMA. Based on quantitative X-ray analysis, together with secondary electron images of individual particles, we successfully identified the aerosol particle types as follows: elemental carbon (EC, organic carbon (OC, (NH42SO4/NH4HSO4-containing, genuine (fresh and reacted (aged sea-salt, mineral dust (such as aluminosilicate, SiO2, CaCO3/CaMg(CO32, etc., and K-containing, Fe-rich, and fly ash particles. By analyzing the relative abundances of different particle types, it was concluded that (a on non-haze days, reacted sea-salts and reacted mineral dust particles were abundant in both the PM2.5–10 and PM1.0–2.5 fractions (with relative abundances of 65.0% and 57.7%, respectively; whereas on haze days, the relative abundances of OC and (NH42SO4/NH4HSO4-containing particles were significantly elevated, indicating that organic matter and secondary aerosols were abundant in the atmosphere

  2. Characterization and quantitative analysis of surfactants in textile wastewater by liquid chromatography/quadrupole-time-of-flight mass spectrometry.

    Science.gov (United States)

    González, Susana; Petrović, Mira; Radetic, Maja; Jovancic, Petar; Ilic, Vesna; Barceló, Damià

    2008-05-01

    A method based on the application of ultra-performance liquid chromatography (UPLC) coupled to hybrid quadrupole-time-of-flight mass spectrometry (QqTOF-MS) with an electrospray (ESI) interface has been developed for the screening and confirmation of several anionic and non-ionic surfactants: linear alkylbenzenesulfonates (LAS), alkylsulfate (AS), alkylethersulfate (AES), dihexyl sulfosuccinate (DHSS), alcohol ethoxylates (AEOs), coconut diethanolamide (CDEA), nonylphenol ethoxylates (NPEOs), and their degradation products (nonylphenol carboxylate (NPEC), octylphenol carboxylate (OPEC), 4-nonylphenol (NP), 4-octylphenol (OP) and NPEO sulfate (NPEO-SO4). The developed methodology permits reliable quantification combined with a high accuracy confirmation based on the accurate mass of the (de)protonated molecules in the TOFMS mode. For further confirmation of the identity of the detected compounds the QqTOF mode was used. Accurate masses of product ions obtained by performing collision-induced dissociation (CID) of the (de)protonated molecules of parent compounds were matched with the ions obtained for a standard solution. The method was applied for the quantitative analysis and high accuracy confirmation of surfactants in complex mixtures in effluents from the textile industry. Positive identification of the target compounds was based on accurate mass measurement of the base peak, at least one product ion and the LC retention time of the analyte compared with that of a standard. The most frequently surfactants found in these textile effluents were NPEO and NPEO-SO4 in concentrations ranging from 0.93 to 5.68 mg/L for NPEO and 0.06 to 4.30 mg/L for NPEO-SO4. AEOs were also identified. PMID:18398847

  3. Characterization of individual submicrometer aerosol particles collected in Incheon, Korea, by quantitative transmission electron microscopy energy-dispersive X-ray spectrometry

    Science.gov (United States)

    Geng, Hong; Kang, Sujin; Jung, Hae-Jin; ChoëL, Marie; Kim, Hyekyeong; Ro, Chul-Un

    2010-08-01

    For the last decade the Monte Carlo calculation method has been proven to be an excellent tool for accurately simulating electron-solid interactions in atmospheric individual particles of micrometer size. Although it was designed for application to scanning electron microscopy, in the present study it is demonstrated that the Monte Carlo calculation can also be applied in a quantitative single particle analysis using transmission electron microscopy (TEM) with an ultrathin window energy-dispersive X-ray (EDX) spectrometer with a high accelerating voltage (200 kV). By utilizing an iterative reverse Monte Carlo simulation combined with successive approximation, atomic elemental concentrations (including low-Z elements) of submicrometer standard particles were determined with high accuracy for electron beam refractory particles such as NaCl, KCl, SiO2, Fe2O3, Na2SO4, K2SO4, CaCO3, and CaSO4. On the basis of quantitative X-ray analysis together with morphological information from TEM images, overall 1638 submicrometer individual particles from 10 sets of aerosol samples collected in Incheon, Korea, were identified. The most frequently encountered particle types are carbonaceous and (NH4)2SO4/NH4HSO4-containing particles, followed by mineral (e.g., aluminosilicate, SiO2, CaCO3), sea salt, K-rich (e.g., K2SO4 and KCl), Fe-rich, fly ash, and transition or heavy-metal-containing (e.g., ZnSO4, ZnCl2, PbSO4) particles. The relative abundances of the submicrometer particle types vary among samples collected in different seasons and also depend on different air mass transport routes. This study demonstrates that the quantitative TEM-EDX individual particle analysis is a useful and reliable technique in characterizing urban submicrometer aerosol particles.

  4. Characterization and diagnostic evaluation of chronic polyneuropathies induced by oxaliplatin and docetaxel comparing skin biopsy to quantitative sensory testing and nerve conduction studies

    DEFF Research Database (Denmark)

    Krøigård, T; Schrøder, H D; Qvortrup, C;

    2014-01-01

    was to characterize the neuropathies with regard to symptoms, neurological signs and objective evidence of damage to the structure and function of the peripheral nerves. Furthermore, the diagnostic values of skin biopsy, quantitative sensory testing (QST) and nerve conduction studies (NCS) were...... fibre density in skin biopsies from the proximal and distal parts of the leg, QST and NCS. RESULTS: Clinically only sensory functions were affected. In general, neuropathy scores were higher in the oxaliplatin-treated group. Both sensory and motor fibres were affected in the NCS, showing predominantly...... after oxaliplatin or docetaxel treatment is a clinically sensory, axonal neuropathy affecting only small nerve fibres in some patients. NCS are often normal, whereas QST and skin biopsy have a higher diagnostic sensitivity....

  5. High-resolution gas chromatography/mass spectrometry method for characterization and quantitative analysis of ginkgolic acids in Ginkgo biloba plants, extracts, and dietary supplements.

    Science.gov (United States)

    Wang, Mei; Zhao, Jianping; Avula, Bharathi; Wang, Yan-Hong; Avonto, Cristina; Chittiboyina, Amar G; Wylie, Philip L; Parcher, Jon F; Khan, Ikhlas A

    2014-12-17

    A high-resolution gas chromatography/mass spectrometry (GC/MS) with selected ion monitor method focusing on the characterization and quantitative analysis of ginkgolic acids (GAs) in Ginkgo biloba L. plant materials, extracts, and commercial products was developed and validated. The method involved sample extraction with (1:1) methanol and 10% formic acid, liquid-liquid extraction with n-hexane, and derivatization with trimethylsulfonium hydroxide (TMSH). Separation of two saturated (C13:0 and C15:0) and six unsaturated ginkgolic acid methyl esters with different positional double bonds (C15:1 Δ8 and Δ10, C17:1 Δ8, Δ10, and Δ12, and C17:2) was achieved on a very polar (88% cyanopropyl) aryl-polysiloxane HP-88 capillary GC column. The double bond positions in the GAs were determined by ozonolysis. The developed GC/MS method was validated according to ICH guidelines, and the quantitation results were verified by comparison with a standard high-performance liquid chromatography method. Nineteen G. biloba authenticated and commercial plant samples and 21 dietary supplements purported to contain G. biloba leaf extracts were analyzed. Finally, the presence of the marker compounds, terpene trilactones and flavonol glycosides for Ginkgo biloba in the dietary supplements was determined by UHPLC/MS and used to confirm the presence of G. biloba leaf extracts in all of the botanical dietary supplements.

  6. Identification and Quantitative Characterization of PSORI-CM01, a Chinese Medicine Formula for Psoriasis Therapy, by Liquid Chromatography Coupled with an LTQ Orbitrap Mass Spectrometer

    Directory of Open Access Journals (Sweden)

    Shao-Dan Chen

    2015-01-01

    Full Text Available PSORI-CM01 is a Chinese medicine formula prepared from medicinal herbs and used in China for the treatment of psoriasis. However, the chemical constituents in PSORI-CM01 have not been clarified yet. In order to quickly define the chemical profiles and control the quality of PSORI-CM01 preparations, ultra-high liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole Orbitrap mass spectrometry (UHPLC-ESI-LTQ/Orbitrap-MS was applied for simultaneous identification and quantification of multiple constituents. A total of 108 compounds, including organic acids, phenolic acids, flavonoids, and terpenoids, were identified or tentatively deduced on the base of their retention behaviors, MS and MSn data, or by comparing with reference substances and literature data. In addition, an optimized UHPLC-ESI-MS method was established for the quantitative determination of 14 marker compounds in different dosage forms of PSORI-CM01 preparations. The validation of the method, including spike recoveries, linearity, sensitivity (LOQ, precision, and repeatability, was carried out and demonstrated to be satisfied the requirements of quantitative analysis. This is the first report on the comprehensive determination of chemical constituents in PSORI-CM01 preparations by UHPLC-ESI-LTQ/Orbitrap mass spectrometry. The results suggested that the established methods would be a powerful and reliable analytical tool for the characterization of multi-constituents in complex chemical system and quality control of TCM preparations.

  7. Sulfonium Ion Derivatization, Isobaric Stable Isotope Labeling and Data Dependent CID- and ETD-MS/MS for Enhanced Phosphopeptide Quantitation, Identification and Phosphorylation Site Characterization

    Science.gov (United States)

    Lu, Yali; Zhou, Xiao; Stemmer, Paul M.; Reid, Gavin E.

    2012-04-01

    An amine specific peptide derivatization strategy involving the use of novel isobaric stable isotope encoded `fixed charge' sulfonium ion reagents, coupled with an analysis strategy employing capillary HPLC, ESI-MS, and automated data dependent ion trap CID-MS/MS, -MS3, and/or ETD-MS/MS, has been developed for the improved quantitative analysis of protein phosphorylation, and for identification and characterization of their site(s) of modification. Derivatization of 50 synthetic phosphopeptides with S, S'-dimethylthiobutanoylhydroxysuccinimide ester iodide (DMBNHS), followed by analysis using capillary HPLC-ESI-MS, yielded an average 2.5-fold increase in ionization efficiencies and a significant increase in the presence and/or abundance of higher charge state precursor ions compared to the non-derivatized phosphopeptides. Notably, 44% of the phosphopeptides (22 of 50) in their underivatized states yielded precursor ions whose maximum charge states corresponded to +2, while only 8% (4 of 50) remained at this maximum charge state following DMBNHS derivatization. Quantitative analysis was achieved by measuring the abundances of the diagnostic product ions corresponding to the neutral losses of `light' (S(CH3)2) and `heavy' (S(CD3)2) dimethylsulfide exclusively formed upon CID-MS/MS of isobaric stable isotope labeled forms of the DMBNHS derivatized phosphopeptides. Under these conditions, the phosphate group stayed intact. Access for a greater number of peptides to provide enhanced phosphopeptide sequence identification and phosphorylation site characterization was achieved via automated data-dependent CID-MS3 or ETD-MS/MS analysis due to the formation of the higher charge state precursor ions. Importantly, improved sequence coverage was observed using ETD-MS/MS following introduction of the sulfonium ion fixed charge, but with no detrimental effects on ETD fragmentation efficiency.

  8. Validation of housekeeping genes in the brains of rats submitted to chronic intermittent hypoxia, a sleep apnea model.

    Science.gov (United States)

    Julian, Guilherme Silva; de Oliveira, Renato Watanabe; Perry, Juliana Cini; Tufik, Sergio; Chagas, Jair Ribeiro

    2014-01-01

    Obstructive sleep apnea (OSA) is a syndrome characterized by intermittent nocturnal hypoxia, sleep fragmentation, hypercapnia and respiratory effort, and it has been associated with several complications, such as diabetes, hypertension and obesity. Quantitative real-time PCR has been performed in previous OSA-related studies; however, these studies were not validated using proper reference genes. We have examined the effects of chronic intermittent hypoxia (CIH), which is an experimental model mainly of cardiovascular consequences of OSA, on reference genes, including beta-actin, beta-2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, hypoxanthine guanine phosphoribosyl transferase and eukaryotic 18S rRNA, in different areas of the brain. All stability analyses were performed using the geNorm, Normfinder and BestKeeper software programs. With exception of the 18S rRNA, all of the evaluated genes were shown to be stable following CIH exposure. However, gene stability rankings were dependent on the area of the brain that was analyzed and varied according to the software that was used. This study demonstrated that CIH affects various brain structures differently. With the exception of the 18S rRNA, all of the tested genes are suitable for use as housekeeping genes in expression analyses.

  9. Validation of housekeeping genes in the brains of rats submitted to chronic intermittent hypoxia, a sleep apnea model.

    Directory of Open Access Journals (Sweden)

    Guilherme Silva Julian

    Full Text Available Obstructive sleep apnea (OSA is a syndrome characterized by intermittent nocturnal hypoxia, sleep fragmentation, hypercapnia and respiratory effort, and it has been associated with several complications, such as diabetes, hypertension and obesity. Quantitative real-time PCR has been performed in previous OSA-related studies; however, these studies were not validated using proper reference genes. We have examined the effects of chronic intermittent hypoxia (CIH, which is an experimental model mainly of cardiovascular consequences of OSA, on reference genes, including beta-actin, beta-2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, hypoxanthine guanine phosphoribosyl transferase and eukaryotic 18S rRNA, in different areas of the brain. All stability analyses were performed using the geNorm, Normfinder and BestKeeper software programs. With exception of the 18S rRNA, all of the evaluated genes were shown to be stable following CIH exposure. However, gene stability rankings were dependent on the area of the brain that was analyzed and varied according to the software that was used. This study demonstrated that CIH affects various brain structures differently. With the exception of the 18S rRNA, all of the tested genes are suitable for use as housekeeping genes in expression analyses.

  10. Validation of Housekeeping Genes in the Brains of Rats Submitted to Chronic Intermittent Hypoxia, a Sleep Apnea Model

    Science.gov (United States)

    Julian, Guilherme Silva; de Oliveira, Renato Watanabe; Perry, Juliana Cini; Tufik, Sergio; Chagas, Jair Ribeiro

    2014-01-01

    Obstructive sleep apnea (OSA) is a syndrome characterized by intermittent nocturnal hypoxia, sleep fragmentation, hypercapnia and respiratory effort, and it has been associated with several complications, such as diabetes, hypertension and obesity. Quantitative real-time PCR has been performed in previous OSA-related studies; however, these studies were not validated using proper reference genes. We have examined the effects of chronic intermittent hypoxia (CIH), which is an experimental model mainly of cardiovascular consequences of OSA, on reference genes, including beta-actin, beta-2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, hypoxanthine guanine phosphoribosyl transferase and eukaryotic 18S rRNA, in different areas of the brain. All stability analyses were performed using the geNorm, Normfinder and BestKeeper software programs. With exception of the 18S rRNA, all of the evaluated genes were shown to be stable following CIH exposure. However, gene stability rankings were dependent on the area of the brain that was analyzed and varied according to the software that was used. This study demonstrated that CIH affects various brain structures differently. With the exception of the 18S rRNA, all of the tested genes are suitable for use as housekeeping genes in expression analyses. PMID:25289636

  11. Usability of ECT for quantitative and qualitative characterization of trickle-bed flow dynamics experiencing filtration conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tibirna, C.; Fortin, A. [Laval Univ., Quebec City, PQ (Canada). GIREF; Edouard, D.; Larachi, F. [Laval Univ., Quebec City, PQ (Canada). Dept. of Chemical Engineering

    2006-07-01

    The feasibility of using electrical capacitance tomography (ECT) as an imaging method for trickle-bed reaction processes was examined in this study. In particular, the advantages and disadvantages of using ECT to characterize the flow dynamics in a four-phase trickle bed reactor were investigated. This work was part of a larger study to extend the service life of catalyst beds used during the hydrotreatment of some oil fractions, such as Athabasca bitumen. A better understanding of the flow dynamics and clogging physics in trickle-bed reactors is needed in order to prevent clogging in the catalyst bed. This study focused on several aspects of the ECT as a non-intrusive imaging method for such processes. This paper described the experimental setup in detail. The ECT equipment allowed for up to 100 tomograms per second to be recorded. The clogging experiments lasted about 30 hours from a completely clean catalyst bed to a stable, non-filtering clogging state. A series of algorithms for ECT image reconstruction were presented. Truncated and filtered single value decomposition (SVD) and Landweber methods were found to be the most appropriate. ECT was shown to be faster and less expensive than nuclear ionizing, non-ionizing and other tomography methods. However, the main advantage of ECT was its non-intrusive attributes. It was also suggested that the complex technologies involved in ECT still require further refinement and better calibration methods. 9 refs., 5 figs.

  12. Quantitative performance characterization of image quality and radiation dose for a CS 9300 dental cone beam computed tomography machine.

    Science.gov (United States)

    Abouei, Elham; Lee, Sierra; Ford, Nancy L

    2015-10-01

    This paper aims to characterize the radiation dose and image quality (IQ) performance of a dental cone beam computed tomography (CBCT) unit over a range of fields of view (FOV). IQ and dose were measured using a Carestream 9300 dental CBCT. Phantoms were positioned in the FOV to imitate clinical positioning. IQ was assessed by scanning a SEDENTEXCT IQ phantom, and images were analyzed in ImageJ. Dose index 1 was obtained using a thimble ionization chamber and SEDENTEXCT DI phantom. Mean gray values agreed within 93.5% to 99.7% across the images, with pixel-to-pixel fluctuations of 6% to 12.5%, with poorer uniformity and increased noise for child protocols. CNR was fairly constant across FOVs, with higher CNR for larger patient settings. The measured limiting spatial resolution agreed well with 10% MTF and bar pattern measurements. Dose was reduced for smaller patient settings within a given FOV; however, smaller FOVs obtained with different acquisition settings did not necessarily result in reduced dose. The use of patient-specific acquisition settings decreased the radiation dose for smaller patients, with minimal impact on the IQ. The full set of IQ and dose measurements is reported to allow dental professionals to compare the different FOV settings for clinical use. PMID:26587550

  13. Reconstruction and Quantitative Characterization of Multiphase, Multiscale Three-Dimensional Microstructure of a Cast Al-Si Base Alloy

    Science.gov (United States)

    Singh, H.; Gokhale, A. M.; Mao, Y.; Tewari, A.; Sachdev, A. K.

    2009-12-01

    The serial sectioning technique is well known for the reconstruction of three-dimensional (3D) microstructures of opaque materials. In recent years, techniques also have been developed for the reconstruction of high-fidelity, large-volume segments of 3D microstructures that use montage serial sections and robot-assisted automated acquisitions of montage serial sections. This article reports the reconstruction of the multiphase, multiscale 3D microstructure of a permanent mold cast unmodified Al-12 wt pct Si-1 wt pct Ni base alloy that contains eutectic Si platelets, coarse primary polyhedral Si particles, Fe-rich script intermetallic particles, and pores. These constituents are segmented, reconstructed, rendered, and characterized in three dimensions. The estimated 3D microstrucutral attributes include the distribution of eutectic platelet thickness; the mean volume, mean surface area, and mean thickness of the eutectic Si platelets; the mean volume and the mean surface area of the polyhedral primary Si particles; and the mean number of faces, edges, and corners on the polyhedral primary Si particles.

  14. Phase contrast imaging X-ray computed tomography: quantitative characterization of human patellar cartilage matrix with topological and geometrical features

    Science.gov (United States)

    Nagarajan, Mahesh B.; Coan, Paola; Huber, Markus B.; Diemoz, Paul C.; Wismüller, Axel

    2014-03-01

    Current assessment of cartilage is primarily based on identification of indirect markers such as joint space narrowing and increased subchondral bone density on x-ray images. In this context, phase contrast CT imaging (PCI-CT) has recently emerged as a novel imaging technique that allows a direct examination of chondrocyte patterns and their correlation to osteoarthritis through visualization of cartilage soft tissue. This study investigates the use of topological and geometrical approaches for characterizing chondrocyte patterns in the radial zone of the knee cartilage matrix in the presence and absence of osteoarthritic damage. For this purpose, topological features derived from Minkowski Functionals and geometric features derived from the Scaling Index Method (SIM) were extracted from 842 regions of interest (ROI) annotated on PCI-CT images of healthy and osteoarthritic specimens of human patellar cartilage. The extracted features were then used in a machine learning task involving support vector regression to classify ROIs as healthy or osteoarthritic. Classification performance was evaluated using the area under the receiver operating characteristic (ROC) curve (AUC). The best classification performance was observed with high-dimensional geometrical feature vectors derived from SIM (0.95 ± 0.06) which outperformed all Minkowski Functionals (p analysis of chondrocyte patterns in human patellar cartilage matrix involving SIM-derived geometrical features can distinguish between healthy and osteoarthritic tissue with high accuracy.

  15. Morphologic characterization and quantitative analysis on in vitro bacteria by nuclear techniques of measurement; Caracterizacao morfologica e analise quantitativa de bacterias in vitro por tecnicas nucleares de medidas

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Joana D' Arc Ramos

    2001-10-01

    The great difficulty to identify microorganisms (bacteria) from infectious processes is related to the necessary time to obtain a reliable result, about 72 hours. The purpose of this work is to establish a faster method to characterize bacterial morphologies through the use of neutron radiography, which can take about 5 hours. The samples containing the microorganisms, bacteria with different morphologies, after the appropriate microbiologic procedures were incubated with B{sup 10} for 30 minutes and soon after deposited in a plate of a solid detector of nuclear tracks (SSNTD), denominated CR-39. To obtain the images relative to bacteria, the detector was submitted to the flow of thermal neutrons of the order of 2.2 x 10{sup 5} n/cm{sup 2}.s from the J-9 channel of the Reactor Argonauta (IEN/CNEN). To observe the images from bacteria in each sample under an optical microscope, the sheets were chemically developed. The analysis of the images revealed morphologic differences among the genera (Gram positive from Gram-negative and coccus from bacillus), in samples containing either isolated or mixed bacteria. We thus verified the viability of the technique to achieve morphological characterization of different microorganisms. A quantitative approach seemed also to be feasible with the technique. The whole process took about 2 hours. (author)

  16. Final technical report for project titled Quantitative Characterization of Cell Aggregation/Adhesion as Predictor for Distribution and Transport of Microorganisms in Subsurface Environment

    Energy Technology Data Exchange (ETDEWEB)

    Gu, April Z [Northeastern University; Wan, Kai-tak [Northeastern Univeristy

    2014-09-02

    This project aims to explore and develop enabling methodology and techniques for nano-scale characterization of microbe cell surface contact mechanics, interactions and adhesion quantities that allow for identification and quantification of indicative properties related to microorganism migration and transport behavior in porous media and in subsurface environments. Microbe transport has wide impact and therefore is of great interest in various environmental applications such as in situ or enhanced subsurface bioremediation,filtration processes for water and wastewater treatments and protection of drinking water supplies. Although great progress has been made towards understanding the identities and activities of these microorganisms in the subsurface, to date, little is known of the mechanisms that govern the mobility and transport of microorganisms in DOE’s contaminated sites, making the outcomes of in situ natural attenuation or contaminant stability enhancement unpredictable. Conventionally, movement of microorganisms was believed to follows the rules governing solute (particle) transport. However, recent studies revealed that cell surface properties, especially those pertaining to cell attachment/adhesion and aggregation behavior, can cause the microbe behavior to deviate from non-viable particles and hence greatly influence the mobility and distribution of microorganisms in porous media.This complexity highlights the need to obtain detailed information of cell-cell and cell-surface interactions in order to improve and refine the conceptual and quantitative model development for fate and transport of microorganisms and contaminant in subsurface. Traditional cell surface characterization methods are not sufficient to fully predict the deposition rates and transport behaviors of microorganism observed. A breakthrough of methodology that would allow for quantitative and molecular-level description of intrinsic cell surface properties indicative for cell

  17. Quantitative film radiography

    International Nuclear Information System (INIS)

    We have developed a system of quantitative radiography in order to produce quantitative images displaying homogeneity of parts. The materials that we characterize are synthetic composites and may contain important subtle density variations not discernible by examining a raw film x-radiograph. In order to quantitatively interpret film radiographs, it is necessary to digitize, interpret, and display the images. Our integrated system of quantitative radiography displays accurate, high-resolution pseudo-color images in units of density. We characterize approximately 10,000 parts per year in hundreds of different configurations and compositions with this system. This report discusses: the method; film processor monitoring and control; verifying film and processor performance; and correction of scatter effects

  18. Direct measurement of oleocanthal and oleacein levels in olive oil by quantitative (1)H NMR. Establishment of a new index for the characterization of extra virgin olive oils.

    Science.gov (United States)

    Karkoula, Evangelia; Skantzari, Angeliki; Melliou, Eleni; Magiatis, Prokopios

    2012-11-28

    A new method for direct measurement of the oleocanthal and oleacein levels in olive oil by quantitative (1)H NMR was developed. The method was applied to the study of 175 monovarietal commercial Greek and California olive oil samples. The main findings were as follows: (1) There was a significant variation concerning the concentrations of oleocanthal and oleacein among the studied samples. Their concentrations ranged from nondetectable to 355 mg/kg and their sum (index D1) from 0 to 501 mg/kg. (2) There are olive varieties that independent of geographic origin and harvest time produce oil that contains both compounds in low levels. (3) There is a positive correlation of a high level of oleocanthal and oleacein in olive oils with the early time of harvest. Although there is a need for more extensive study, a new index for the characterization of extra virgin olive oils, which is a combination of D1 = oleocanthal + oleacein level and D2 = oleocanthal/oleacein ratio, seems to be very useful. PMID:23116297

  19. Inverse PCR and Quantitative PCR as Alternative Methods to Southern Blotting Analysis to Assess Transgene Copy Number and Characterize the Integration Site in Transgenic Woody Plants.

    Science.gov (United States)

    Stefano, Biricolti; Patrizia, Bogani; Matteo, Cerboneschi; Massimo, Gori

    2016-06-01

    One of the major unanswered questions with respect to the commercial use of genetic transformation in woody plants is the stability of the transgene expression over several decades within the same individual. Gene expression is strongly affected by the copy number which has been integrated into the plant genome and by the local DNA features close to the integration sites. Because woody plants cannot be subjected to selfing or backcrossing to modify the transgenic allelic structure without affecting the valuable traits of the cultivar, molecular characterization of the transformation event is therefore crucial. After assessing the transgene copy number of a set of apple transgenic clones with Southern blotting, we describe two alternative methods: the first is based on inverse PCR (i-PCR) and the second on the quantitative PCR (q-PCR). The methods produced comparable results with the exception of the data regarding a high copy number clone, but while the q-PCR-based system is rapid and easily adaptable to high throughput systems, the i-PCR-based method can provide information regarding the transformation event and the characteristics of the sequences flanking the transgenic construct.

  20. Nondestructive and quantitative characterization of TRU and LLW mixed-waste using active and passive gamma-ray spectrometry and computed tomography

    International Nuclear Information System (INIS)

    The technology being proposed by LLNL is an Active and Passive Computed Tomography (A ampersand P CT) Drum Scanner for contact-handled (CH) wastes. It combines the advantages offered by two well-developed nondestructive assay technologies: gamma-ray spectrometry and computed tomography (CT). Coupled together, these two technologies offer to nondestructively and quantitatively characterize mixed- wastes forms. Gamma-ray spectroscopy uses one or more external radiation detectors to passively and nondestructively measure the energy spectrum emitted from a closed container. From the resulting spectrum one can identify most radioactivities detected, be they transuranic isotopes, mixed-fission products, activation products or environmental radioactivities. Spectral libraries exist at LLNL for all four. Active (A) or transmission CT is a well-developed, nondestructive medical and industrial technique that uses an external-radiation beam to map regions of varying attenuation within a container. Passive (P) or emission CT is a technique mainly developed for medical application, e.g., single-photon emission CT. Nondestructive industrial uses of PCT are under development and just coming into use. This report discuses work on the A ampersand P CT Drum Scanner at LLNL

  1. Stand-replacing patches within a `mixed severity' fire regime: quantitative characterization using recent fires in a long-established natural fire area

    Science.gov (United States)

    Collins, B.; Stephens, S.

    2010-12-01

    The complexity inherent in variable, or mixed-severity fire regimes makes quantitative characterization of important fire regime attributes (e.g., proportion of landscape burned at different severities, size and distribution of stand-replacing patches) difficult. As a result, there is ambiguity associated with the term ‘mixed-severity’. We address this ambiguity through spatial analysis of two recent wildland fires in upper elevation mixed-conifer forests that occurred in an area with over 30 years of relatively freely-burning natural fires. We take advantage of robust estimates of fire severity and detailed spatial datasets to investigate patterns and controls on stand-replacing patches within these fires. Stand-replacing patches made up 15 % of the total burned area between the two fires, which consisted of many small patches ( 60 ha). Smaller stand-replacing patches were generally associated with shrub-dominated (Arctostaphylos spp. and Ceanothus spp.) and pine-dominated vegetation types, while larger stand-replacing patches tended to occur in more shade-tolerant, fir-dominated types. Additionally, in shrub-dominated types stand-replacing patches were often constrained to the underlying patch of vegetation, which for the shrub type were smaller across the two fire areas than vegetation patches for all other dominant vegetation types. For white and red fir forest types we found little evidence of vegetation patch constraint on the extent of stand-replacing patches. The patch dynamics we identified can be used to inform management strategies for landscapes in similar forest types.

  2. TU-C-12A-07: Characterization of Longitudinal Reproducibility of Quantitative Diffusion Imaging Data Acquired with Four Different Protocols Using a Phantom

    Energy Technology Data Exchange (ETDEWEB)

    Li, X [Georgia Regents University - Athens, Athens, Georgia (United States); Buzzelli, M; Randazzo, W; Yanasak, N [Georgia Regents University, Augusta, GA (Georgia)

    2014-06-15

    Purpose: To characterize and compare the longitudinal reproducibility of diffusion imaging data acquired with four different protocols using a phantom. Methods: The Diffusive Quantitative Imaging Phantom (DQIP) was constructed using fifteen cylindrical compartments within a larger compartment, filled with deionized water doped with CuSO4 and NaCl. The smaller compartments contained arrays of hexagonal or cylindrical glass capillaries of varying inner diameters, for differing restraint of water diffusion. The sensitivity of diffusion imaging metrics to signal-to-noise ratio (SNR) was probed by doping compartments with differing ratios of deuterium oxide to H2O. A cork phantom enclosure was constructed to increase thermal stability during scanning and a cork holder was made to reproduce scanner positioning. Four different protocols of DWI (diffusion weighted imaging) and DTI (Diffusion tensor imaging) imaging were assembled on a GE Excite HDx 3.0T MRI scanner to collect imaging data over 9-10 days. Data was processed with in-house software created in Matlab to obtain fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values. Results: All DTI and DWI sequences showed good longitudinal stability of mean FA and ADC values per compartment, exhibiting low standard deviation ∼9%. A t-test was performed to compare mean FA values from the DTI clinical protocol to those of the DTI special protocol, indicating significantly different values in the majority of compartments. ANOVA performed on ADC values for all DTI and DWI sequences also showed significantly different values in a majority of compartments. Conclusion: This work has the potential for quantifying systemic variations between diffusion imaging sequences from different platforms. Characterization of DWI and DTI performance were done over four sequences with predictable results. This data suggests that the DQIP phantom may be a reliable method of monitoring day-to-day and scan-to-scan variation in

  3. Assessment of vulnerability in karst aquifers using a quantitative integrated numerical model: catchment characterization and high resolution monitoring - Application to semi-arid regions- Lebanon.

    Science.gov (United States)

    Doummar, Joanna; Aoun, Michel; Andari, Fouad

    2016-04-01

    Karst aquifers are highly heterogeneous and characterized by a duality of recharge (concentrated; fast versus diffuse; slow) and a duality of flow which directly influences groundwater flow and spring responses. Given this heterogeneity in flow and infiltration, karst aquifers do not always obey standard hydraulic laws. Therefore the assessment of their vulnerability reveals to be challenging. Studies have shown that vulnerability of aquifers is highly governed by recharge to groundwater. On the other hand specific parameters appear to play a major role in the spatial and temporal distribution of infiltration on a karst system, thus greatly influencing the discharge rates observed at a karst spring, and consequently the vulnerability of a spring. This heterogeneity can only be depicted using an integrated numerical model to quantify recharge spatially and assess the spatial and temporal vulnerability of a catchment for contamination. In the framework of a three-year PEER NSF/USAID funded project, the vulnerability of a karst catchment in Lebanon is assessed quantitatively using a numerical approach. The aim of the project is also to refine actual evapotranspiration rates and spatial recharge distribution in a semi arid environment. For this purpose, a monitoring network was installed since July 2014 on two different pilot karst catchment (drained by Qachqouch Spring and Assal Spring) to collect high resolution data to be used in an integrated catchment numerical model with MIKE SHE, DHI including climate, unsaturated zone, and saturated zone. Catchment characterization essential for the model included geological mapping and karst features (e.g., dolines) survey as they contribute to fast flow. Tracer experiments were performed under different flow conditions (snow melt and low flow) to delineate the catchment area, reveal groundwater velocities and response to snowmelt events. An assessment of spring response after precipitation events allowed the estimation of the

  4. Quantitative research.

    Science.gov (United States)

    Watson, Roger

    2015-04-01

    This article describes the basic tenets of quantitative research. The concepts of dependent and independent variables are addressed and the concept of measurement and its associated issues, such as error, reliability and validity, are explored. Experiments and surveys – the principal research designs in quantitative research – are described and key features explained. The importance of the double-blind randomised controlled trial is emphasised, alongside the importance of longitudinal surveys, as opposed to cross-sectional surveys. Essential features of data storage are covered, with an emphasis on safe, anonymous storage. Finally, the article explores the analysis of quantitative data, considering what may be analysed and the main uses of statistics in analysis.

  5. STUDY ON THE SEQUENCE STRUCTURE OF BUTADIENE-STYRENE RUBBER BY 13C-NMR METHOD Ⅲ. QUANTITATIVE CHARACTERIZATION OF SEQUENCE STRUCTURE

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiaonong; HU Liping; YAN Baozhen; JIAO Shuke

    1990-01-01

    The quantitative description of the sequence structure of emulsion-processed SBR and solution-processed SBR (by lithium catalyst)was carried out based on their spectral data of 13C-NMR.The calculating formulae which could be used to obtain diad concentration from the peak intensities of carbon spectra, average block length, average number of block, and the microstructure composition of the molecular chain were derived. The quantitative result showed that on the molecular chain styrene unit had the tendency to attach to trans-1,4 butadiene unit. The calculated result of the microstructure was in good agreement with that obtained through IR measurement.

  6. Characterization, quantitation and evolution of monoepoxy compounds formed in model systems of fatty acid methyl esters and monoacid triglycerides heated at high temperature

    Directory of Open Access Journals (Sweden)

    Berdeaux, O.

    1999-02-01

    Full Text Available Monoepoxy compounds formed after heating methyl oleate and linoleate, triolein and trilinolein at 180°C for 5, 10 and 15 hours, were characterized and quantitated after derivatization to fatty acid methyl esters by using two base-catalyzed procedures. Structures were identified by GC-MS before and after hydrogénation. A complete recovery of the epoxy compounds was obtained by comparing results from methyl oleate and linoleate before and after transesterification, and good repeatability was also attained. Similar amounts of epoxides were found for methyl esters and triglycerides of the same degree of unsaturation, although formation was considerably greater for the less unsaturated substrates, methyl oleate and triolein, possibly due to the absence of remaining double bonds in the molecule which would involve a lower tendency to participate in further reactions. On other hand, independently of the degree of unsaturation of the model systems and of the period of heating, significantly higher amounts of trans isomers were formed. Finally from comparison between the amounts of epoxides and the level of polar fatty acids in samples, it was deduced that monoepoxy compounds were one of the major groups formed under the conditions used.

    En este estudio se identifican y cuantifican los compuestos epoxidados formados a partir de sistemas modelo de oleato y linoleato de metilo, trioleína y trilinoleína, calentados a 180°C durante 5,10 y 15 horas. La identificación se lleva a cabo mediante CG-EM en las muestras de esteres metílicos antes y después de someter a hidrogenación y para su cuantificación se utilizan dos procedimientos de transesterificación en medio alcalino. La comparación de las cantidades obtenidas, antes y después de la derivatización de los sistemas modelo de esteres metílicos, permitió deducir que la recuperación fue completa, obteniéndose también una excelente repetibilidad. Las cantidades de ep

  7. Suitability of thin-layer chromatography-flame ionization detection with regard to quantitative characterization of different fossil fuel products. II. Calibration methods concerning quantitative hydrocarbon-group type analysis

    Energy Technology Data Exchange (ETDEWEB)

    Vela, J.; Membrado, L.; Cebolla, V.L.; Ferrando, A.C. [CSIC, Zaragoza (Spain). Inst. de Carboquimica, Dept. de Procesos Quimicos

    1998-10-01

    Time-consuming external standard-based calibration methods are usually performed for hydrocarbon group type analysis (HGTA) of fossil fuels, regardless of the instrumental chromatographic technique. HGTA of a broad variety of coal and petroleum products was performed using a modern thin-layer chromatography-flame ionization detection (TLC-FID) system and a rapid method based on internal normalization. Repeatability, linear intervals, and sample load ranges for quantitative application of this method are given, namely a heavy oil and its derived hydrocracked products, raw and chemically-modified petroleum asphaltenes, a coal-tar pitch, several coal extracts, and coal hydroliquefaction products. Results from external standard calibration and a normalization method (both obtained by TLC-FID) are in agreement, and they are validated using TLC-ultraviolet scanning. The use of the latter demonstrates that TLC-FID can also be applied to products such as coal extracts and hydroliquefaction products, despite these products being more volatile than petroleum asphaltenes or heavy oils. 14 refs., 3 figs., 5 tabs.

  8. Quantitative graph theory mathematical foundations and applications

    CERN Document Server

    Dehmer, Matthias

    2014-01-01

    The first book devoted exclusively to quantitative graph theory, Quantitative Graph Theory: Mathematical Foundations and Applications presents and demonstrates existing and novel methods for analyzing graphs quantitatively. Incorporating interdisciplinary knowledge from graph theory, information theory, measurement theory, and statistical techniques, this book covers a wide range of quantitative-graph theoretical concepts and methods, including those pertaining to real and random graphs such as:Comparative approaches (graph similarity or distance)Graph measures to characterize graphs quantitat

  9. Qualitative and quantitative characterization of phenolic and diterpenoid constituents in Danshen (Salvia miltiorrhiza) by comprehensive two-dimensional liquid chromatography coupled with hybrid linear ion trap Orbitrap mass.

    Science.gov (United States)

    Cao, Ji-Liang; Wei, Jin-Chao; Hu, Yuan-Jia; He, Cheng-Wei; Chen, Mei-Wan; Wan, Jian-Bo; Li, Peng

    2016-01-01

    Danshen is one of the most frequently used traditional Chinese herbs owing to its remarkable and reliable therapeutic effects. Phenolic acids and diterpenoids have proved to be the bioactive substance groups. In order to fully profile its chemical compositions and explore new potential bioactive compounds, a comprehensive two-dimensional liquid chromatography system coupled to DAD detector and hybrid linear ion trap (LTQ) Orbitrap mass spectrometry (LC × LC-DAD-ESI/HRMS/MS(n)) was set up in this study based on the column combination of Hypersil gold CN (150 mm × 1 mm, 3 μm) and Accucore C18 (50 mm × 4.6 mm, 2.6 μm). Using the optimal segment gradient program, phenolic acids and diterpenoids were separated into two independent groups and a total of 328 peaks were successfully detected on the contour plot of Danshen. By means of the accurate mass and reliable MS(n) data, 102 compounds were identified or tentatively identified and 7 of them were discovered from Danshen for the first time. Moreover, the LC × LC-DAD system was validated for the quantitative analysis of 14 bioactive analytes using the contour plot, exhibiting satisfactory linearity (r ≥ 0.9976) and high precision for both peak locating (≤ 1.07%) and peak volume calculating (0.34%-4.11%). The established method could afford powerful separation capability, reliable identification data and accurate quantitative results, which is very suitable for analysis of complex herbal samples. PMID:26687169

  10. Characterization of the Key Odorants in Chinese Zhima Aroma-Type Baijiu by Gas Chromatography-Olfactometry, Quantitative Measurements, Aroma Recombination, and Omission Studies.

    Science.gov (United States)

    Zheng, Yang; Sun, Baoguo; Zhao, Mouming; Zheng, Fuping; Huang, Mingquan; Sun, Jinyuan; Sun, Xiaotao; Li, Hehe

    2016-07-01

    Zhima aroma-type Baijiu with typical sesame aroma is particularly popular in northern China. To our knowledge, it is still uncertain which components are important to make contributions to its unique aroma, although a few pieces of research have reported many volatile compounds in this Baijiu. The aroma-active compounds from the Baijiu were researched in this paper. A total of 56 odorants were identified in Chinese Zhima aroma-type Baijiu by aroma extract dilution analysis (AEDA). Their odor activity values (OAVs) were determined by different quantitative measurements, and then 26 aroma compounds were further confirmed as important odorants due to their OAVs ≥ 1, and these had higher values, such as ethyl hexanoate (OAV 2691), 3-methylbutanal (2403), ethyl pentanoate (1019), and so on. The overall aroma of Zhima aroma-type Baijiu could be simulated by mixing of the 26 key odorants in their measured concentrations. The similarity of the overall aroma profiles between the recombination model and the commercial sample was judged to be 2.7 out of 3.0 points. Omission experiments further corroborated the importance of methional and ethyl hexanoate for the overall aroma of Chinese Zhima aroma-type Baijiu. PMID:27263543

  11. Quantitative Characterization of the Interaction Space of the Mammalian Carbonic Anhydrase Isoforms I, II, VII, IX, XII, and XIV and their Inhibitors, Using the Proteochemometric Approach.

    Science.gov (United States)

    Rasti, Behnam; Karimi-Jafari, Mohammad H; Ghasemi, Jahan B

    2016-09-01

    The critical role of carbonic anhydrases in different physiological processes has put this protein family at the center of attention, challenging major diseases like glaucoma, neurological disorders such as epilepsy and Alzheimer's disease, obesity, and cancers. Many QSAR/QSPR (quantitative structure-activity/property relationship) researches have been carried out to design potent carbonic anhydrase inhibitors (CAIs); however, using inhibitors with no selectivity for different isoforms can lead to major side-effects. Given that QSAR/QSPR methods are not capable of covering multiple targets in a unified model, we have applied the proteochemometric approach to model the interaction space that governs selective inhibition of different CA isoforms by some mono-/dihydroxybenzoic acid esters. Internal and external validation methods showed that all models were reliable in terms of both validity and predictivity, whereas Y-scrambling assessed the robustness of the models. To prove the applicability of our models, we showed how structural changes of a ligand can affect the selectivity. Our models provided interesting information that can be useful for designing inhibitors with selective behavior toward isoforms of carbonic anhydrases, aiding in their selective inhibition. PMID:26990115

  12. Quantitative characterization of pulverized coal and biomass–coal blends in pneumatic conveying pipelines using electrostatic sensor arrays and data fusion techniques

    International Nuclear Information System (INIS)

    Quantitative data about the dynamic behaviour of pulverized coal and biomass–coal blends in fuel injection pipelines allow power plant operators to detect variations in fuel supply and oscillations in the flow at an early stage, enable them to balance fuel distribution between fuel feeding pipes and ultimately to achieve higher combustion efficiency and lower greenhouse gas emissions. Electrostatic sensor arrays and data fusion algorithms are combined to provide a non-intrusive solution to the measurement of fuel particle velocity, relative solid concentration and flow stability under pneumatic conveying conditions. Electrostatic sensor arrays with circular and arc-shaped electrodes are integrated in the same sensing head to measure ‘averaged’ and ‘localized’ characteristics of pulverized fuel flow. Data fusion techniques are applied to optimize and integrate the results from the sensor arrays. Experimental tests were conducted on the horizontal section of a 150 mm bore pneumatic conveyor circulating pulverized coal and sawdust under various flow conditions. Test results suggest that pure coal particles travel faster and carry more electrostatic charge than biomass–coal blends. As more biomass particles are added to the flow, the overall velocity of the flow reduces, the electrostatic charge level on particles decreases and the flow becomes less stable compared to the pure coal flow. (paper)

  13. A SELDI-TOF MS procedure for the detection, quantitation, and preliminary characterization of low-molecular-weight recombinant proteins expressed in transgenic plants.

    Science.gov (United States)

    Badri, M Amine; Rivard, Daniel; Coenen, Karine; Vaillancourt, Louis-Philippe; Goulet, Charles; Michaud, Dominique

    2009-01-01

    We describe a SELDI-TOF MS procedure for the rapid detection and quantitation of low-molecular-weight recombinant proteins expressed in plants. Transgenic lines of potato (Solanum tuberosum L.) expressing the clinically useful protein bovine aprotinin or the cysteine protease inhibitor corn cystatin II were generated by Agrobacterium tumefaciens-mediated transformation, and then used as test material for the analyses. Real-time RT-PCR amplifications and detection of the recombinant proteins by immunoblotting were first conducted for transformed potato lines accumulating the proteins in different cell compartments. Both proteins were found at varying levels in leaves, depending on their final cellular destination and transgene expression rate. These conclusions drawn from standard immunodetection assays were easily confirmed by SELDI-TOF MS comparative profiling, after immobilizing the leaf proteins of control and transformed lines on protein biochips for weak cationic exchange. This procedure, carried out in less than 2 h, allows for the rapid comparison of recombinant protein levels in transgenic plant lines. The molecular weight of immobilized proteins can also be determined directly from the MS spectra, thus providing a simple way to assess the structural integrity and homogeneity of recombinant proteins in planta, and to identify the most suitable cellular compartments for their heterologous production.

  14. Quantitative characterization of the protein contents of the exocrine pancreatic acinar cell by soft x-ray microscopy and advanced digital imaging methods

    Energy Technology Data Exchange (ETDEWEB)

    Loo Jr., Billy W.

    2000-06-09

    The study of the exocrine pancreatic acinar cell has been central to the development of models of many cellular processes, especially of protein transport and secretion. Traditional methods used to examine this system have provided a wealth of qualitative information from which mechanistic models have been inferred. However they have lacked the ability to make quantitative measurements, particularly of the distribution of protein in the cell, information critical for grounding of models in terms of magnitude and relative significance. This dissertation describes the development and application of new tools that were used to measure the protein content of the major intracellular compartments in the acinar cell, particularly the zymogen granule. Soft x-ray microscopy permits image formation with high resolution and contrast determined by the underlying protein content of tissue rather than staining avidity. A sample preparation method compatible with x-ray microscopy was developed and its properties evaluated. Automatic computerized methods were developed to acquire, calibrate, and analyze large volumes of x-ray microscopic images of exocrine pancreatic tissue sections. Statistics were compiled on the protein density of several organelles, and on the protein density, size, and spatial distribution of tens of thousands of zymogen granules. The results of these measurements, and how they compare to predictions of different models of protein transport, are discussed.

  15. Preliminary evaluation of a fully automated quantitative framework for characterizing general breast tissue histology via color histogram and color texture analysis

    Science.gov (United States)

    Keller, Brad M.; Gastounioti, Aimilia; Batiste, Rebecca C.; Kontos, Despina; Feldman, Michael D.

    2016-03-01

    Visual characterization of histologic specimens is known to suffer from intra- and inter-observer variability. To help address this, we developed an automated framework for characterizing digitized histology specimens based on a novel application of color histogram and color texture analysis. We perform a preliminary evaluation of this framework using a set of 73 trichrome-stained, digitized slides of normal breast tissue which were visually assessed by an expert pathologist in terms of the percentage of collagenous stroma, stromal collagen density, duct-lobular unit density and the presence of elastosis. For each slide, our algorithm automatically segments the tissue region based on the lightness channel in CIELAB colorspace. Within each tissue region, a color histogram feature vector is extracted using a common color palette for trichrome images generated with a previously described method. Then, using a whole-slide, lattice-based methodology, color texture maps are generated using a set of color co-occurrence matrix statistics: contrast, correlation, energy and homogeneity. The extracted features sets are compared to the visually assessed tissue characteristics. Overall, the extracted texture features have high correlations to both the percentage of collagenous stroma (r=0.95, phistological processes in digitized histology specimens.

  16. [Exploration of a quantitative methodology to characterize the retention of PM2.5 and other atmospheric particulate matter by plant leaves: taking Populus tomentosa as an example].

    Science.gov (United States)

    Zhang, Zhi-Dan; Xi, Ben-Ye; Cao, Zhi-Guo; Jia, Li-Ming

    2014-08-01

    Taking Populus tomentosa as an example, a methodology called elution-weighing-particle size-analysis (EWPA) was proposed to evaluate quantitatively the ability of retaining fine particulate matter (PM2.5, diameter d ≤ 2.5 μm) and atmospheric particulate matter by plant leaves using laser particle size analyzer and balance. This method achieved a direct, accurate measurement with superior operability about the quality and particle size distribution of atmospheric particulate matter retained by plant leaves. First, a pre-experiment was taken to test the stability of the method. After cleaning, centrifugation and drying, the particulate matter was collected and weighed, and then its particle size distribution was analyzed by laser particle size analyzer. Finally, the mass of particulate matter retained by unit area of leaf and stand was translated from the leaf area and leaf area index. This method was applied to a P. tomentosa stand which had not experienced rain for 27 days in Beijing Olympic Forest Park. The results showed that the average particle size of the atmospheric particulate matter retained by P. tomentosa was 17.8 μm, and the volume percentages of the retained PM2.5, inhalable particulate matter (PM10, d ≤ 10 μm) and total suspended particle (TSP, d ≤ 100 μm) were 13.7%, 47.2%, and 99.9%, respectively. The masses of PM2.5, PM10, TSP and total particulate matter were 8.88 x 10(-6), 30.6 x 10(-6), 64.7 x 10(-6) and 64.8 x 10(-6) g x cm(-2) respectively. The retention quantities of PM2.5, PM10, TSP and total particulate matter by the P. tomentosa stand were 0.963, 3.32, 7.01 and 7.02 kg x hm(-2), respectively.

  17. PET-based compartmental modeling of {sup 124}I-A33 antibody: quantitative characterization of patient-specific tumor targeting in colorectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Zanzonico, Pat; O' Donoghue, Joseph A.; Humm, John L. [Memorial Sloan Kettering Cancer Center, Department of Medical Physics, New York, NY (United States); Carrasquillo, Jorge A.; Pandit-Taskar, Neeta; Ruan, Shutian; Larson, Steven M. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Smith-Jones, Peter [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Stony Brook School of Medicine, Departments of Psychiatry and Radiology, Stony Brook, NY (United States); Divgi, Chaitanya [Columbia University Medical Center, New York, NY (United States); Scott, Andrew M. [La Trobe University, Olivia Newton-John Cancer Research Institute, Melbourne (Australia); Kemeny, Nancy E.; Wong, Douglas; Scheinberg, David [Memorial Sloan Kettering Cancer Center, Department of Medicine, New York, NY (United States); Fong, Yuman [Memorial Sloan Kettering Cancer Center, Department of Surgery, New York, NY (United States); City of Hope, Department of Surgery, Duarte, CA (United States); Ritter, Gerd; Jungbluth, Achem; Old, Lloyd J. [Memorial Sloan Kettering Cancer Center, Ludwig Institute for Cancer Research, New York, NY (United States)

    2015-10-15

    The molecular specificity of monoclonal antibodies (mAbs) directed against tumor antigens has proven effective for targeted therapy of human cancers, as shown by a growing list of successful antibody-based drug products. We describe a novel, nonlinear compartmental model using PET-derived data to determine the ''best-fit'' parameters and model-derived quantities for optimizing biodistribution of intravenously injected {sup 124}I-labeled antitumor antibodies. As an example of this paradigm, quantitative image and kinetic analyses of anti-A33 humanized mAb (also known as ''A33'') were performed in 11 colorectal cancer patients. Serial whole-body PET scans of {sup 124}I-labeled A33 and blood samples were acquired and the resulting tissue time-activity data for each patient were fit to a nonlinear compartmental model using the SAAM II computer code. Excellent agreement was observed between fitted and measured parameters of tumor uptake, ''off-target'' uptake in bowel mucosa, blood clearance, tumor antigen levels, and percent antigen occupancy. This approach should be generally applicable to antibody-antigen systems in human tumors for which the masses of antigen-expressing tumor and of normal tissues can be estimated and for which antibody kinetics can be measured with PET. Ultimately, based on each patient's resulting ''best-fit'' nonlinear model, a patient-specific optimum mAb dose (in micromoles, for example) may be derived. (orig.)

  18. Characterization of the collagen component of cartilage repair tissue of the talus with quantitative MRI: comparison of T2 relaxation time measurements with a diffusion-weighted double-echo steady-state sequence (dwDESS)

    Energy Technology Data Exchange (ETDEWEB)

    Kretzschmar, M.; Hainc, N.; Studler, U. [University Hospital Basel, Department of Radiology, Basel (Switzerland); Bieri, O. [University Hospital Basel, Division of Radiological Physics, Basel (Switzerland); Miska, M. [University Hospital, Department of Orthopedics, Heidelberg (Germany); Wiewiorski, M.; Valderrabano, V. [University Hospital Basel, Department of Orthopedic Surgery, Basel (Switzerland)

    2015-04-01

    The purpose of this study was to characterize the collagen component of repair tissue (RT) of the talus after autologous matrix-induced chondrogenesis (AMIC) using quantitative T2 and diffusion-weighted imaging. Mean T2 values and diffusion coefficients of AMIC-RT and normal cartilage of the talus of 25 patients with posttraumatic osteochondral lesions and AMIC repair were compared in a cross-sectional design using partially spoiled steady-state free precession (pSSFP) for T2 quantification, and diffusion-weighted double-echo steady-state (dwDESS) for diffusion measurement. RT and cartilage were graded with modified Noyes and MOCART scores on morphological sequences. An association between follow-up interval and quantitative MRI measures was assessed using multivariate regression, after stratifying the cohort according to time interval between surgery and MRI. Mean T2 of the AMIC-RT and cartilage were 43.1 ms and 39.1 ms, respectively (p = 0.26). Mean diffusivity of the RT (1.76 μm{sup 2}/ms) was significantly higher compared to normal cartilage (1.46 μm{sup 2}/ms) (p = 0.0092). No correlation was found between morphological and quantitative parameters. RT diffusivity was lowest in the subgroup with follow-up >28 months (p = 0.027). Compared to T2-mapping, dwDESS demonstrated greater sensitivity in detecting differences in the collagen matrix between AMIC-RT and cartilage. Decreased diffusivity in patients with longer follow-up times may indicate an increased matrix organization of RT. (orig.)

  19. Identification of phenolic compounds in plum fruits (Prunus salicina L. and Prunus domestica L.) by high-performance liquid chromatography/tandem mass spectrometry and characterization of varieties by quantitative phenolic fingerprints.

    Science.gov (United States)

    Jaiswal, Rakesh; Karaköse, Hande; Rühmann, Susanne; Goldner, Katharina; Neumüller, Michael; Treutter, Dieter; Kuhnert, Nikolai

    2013-12-11

    Plums (Prunus domestica L. and Prunus salicina L.) are edible fruits mostly consumed in America, China, and Europe. We have used LC-MS(n) to detect and characterize the phenolic compounds in plum varieties. Forty-one phenolics were detected comprising caffeoylquinic acids, feruloylquinic acid, p-coumaroylquinic acids, methyl caffeoylquinates, methyl p-coumaroylquinate, caffeoylshikimic acids, catechin, epicatechin, rutin, esculin, quercetin, quercetin-3-O-hexosides, dimeric proanthocyanidins, trimeric proanthocyanidins, caffeoyl-glucoside, feruloyl-glucoside, p-coumaroyl-glucoside, vanillic acid-glucosides, 3,4-dihydroxybenzoyl-glucoside, quercetin-3-O-pentosides, quercetin-3-O-rhamnoside, quercetin-pentoside-rhamnosides, and 3-p-methoxycinnamoylquinic acid. This is the first time when 3-p-methoxycinnamoylquinic acid is reported in nature. Chlorogenic acids and proanthocyanidins were the major phenolics present in plums. Furthermore, HPLC with DAD and chemical reaction detection was used to generate quantitative phenolic fingerprints from the fruit flesh of 33 plum varieties. The predominant compound was 3-caffeoylquinic acid in nearly all varieties studied; generally, however, the qualitative and quantitative profiles showed high diversity even among closely related progenies.

  20. Qualitative and Quantitative Characterization of Porosity in a Low Porous and Low Permeable Organic Rich Shale by Combining Broad Ion Beam and Scanning Electron Microscopy (BIB-SEM)

    International Nuclear Information System (INIS)

    This contribution focuses on the characterization of porosity in low porous shale using a broad ion beam (BIB) polishing technique combined with a conventional scanning electron microscopy (SEM). Porosity was traced in certain representative elementary areas (REA) and pores detected are segmented from mosaics of secondary electron (SE) images. Traced pores could be classified into two major pore-size classes. Relative large pores (> 0.5 μm2) were found in the organic matter and matrix. They contribute strongly to the overall porosity con-tent of the shale. Nevertheless the far majority of the pores traced have equivalent radius less than 400 nm. Including the latter pore class, the imaged porosity from both samples gives similar results in the order of < 1 %. (authors)

  1. Metabolic alterations produced by 3-nitropropionic acid in rat striata and cultured astrocytes: quantitative in vitro 1H nuclear magnetic resonance spectroscopy and biochemical characterization

    International Nuclear Information System (INIS)

    Quantitative high resolution in vitro 1H nuclear magnetic resonance spectroscopy was employed to study the metabolic effects of 3-nitropropionic acid associated with aging from perchloric acid extracts of rat striata. Systemic injection of 3-nitropropionic acid in rats at a dose of 10 mg/kg/day for seven consecutive days significantly impaired energy metabolism in rats one, four and eight months of age, as evidenced by a marked elevation of succinate and lactate levels. However, a significant decrease in N-acetyl-l-aspartate level, a neuronal marker, was observed in four- and eight-month-old rats but not in one-month-old rats. This would indicate that rats at four to eight months are more susceptible to 3-nitropropionic acid than those at one month. A significant decrease in GABA level was observed in four-month-old 3-nitropropionic acid-treated rats, which is consistent with the literature that GABAergic neurons are particularly vulnerable to 3-nitropropionic acid treatment. In addition, glutamine and glutamate levels were markedly decreased at four and eight months in 3-nitropropionic acid-treated rats. Since glutamine is synthesized predominantly in glia, the observation above suggests that 3-nitropropionic acid intoxication may involve perturbation of energy metabolism, glial injury and consequent neuronal damage. Astrocytes which are essential in the metabolism of glutamate and glutamine were used to further assess 3-nitropropionic acid-induced toxicity. Glial proliferation, mitochondrial metabolism and glutamine synthetase activity were all reduced by 3-nitropropionic acid treatment with a concomitant increase, in a dose-dependent manner, of lactate levels, suggesting that 3-nitropropionic acid is also detrimental to astrocytes in vivo and thus may affect metabolic interaction between neurons and glia.These results not only imply that 3-nitropropionic acid blocks energy metabolism prior to exerting neurotoxic damage but also demonstrate that the degree of

  2. Quantitative characterization of metabolism and metabolic shifts during growth of the new human cell line AGE1.HN using time resolved metabolic flux analysis.

    Science.gov (United States)

    Niklas, Jens; Schräder, Eva; Sandig, Volker; Noll, Thomas; Heinzle, Elmar

    2011-06-01

    For the improved production of vaccines and therapeutic proteins, a detailed understanding of the metabolic dynamics during batch or fed-batch production is requested. To study the new human cell line AGE1.HN, a flexible metabolic flux analysis method was developed that is considering dynamic changes in growth and metabolism during cultivation. This method comprises analysis of formation of cellular components as well as conversion of major substrates and products, spline fitting of dynamic data and flux estimation using metabolite balancing. During batch cultivation of AGE1.HN three distinct phases were observed, an initial one with consumption of pyruvate and high glycolytic activity, a second characterized by a highly efficient metabolism with very little energy spilling waste production and a third with glutamine limitation and decreasing viability. Main events triggering changes in cellular metabolism were depletion of pyruvate and glutamine. Potential targets for the improvement identified from the analysis are (i) reduction of overflow metabolism in the beginning of cultivation, e.g. accomplished by reduction of pyruvate content in the medium and (ii) prolongation of phase 2 with its highly efficient energy metabolism applying e.g. specific feeding strategies. The method presented allows fast and reliable metabolic flux analysis during the development of producer cells and production processes from microtiter plate to large scale reactors with moderate analytical and computational effort. It seems well suited to guide media optimization and genetic engineering of producing cell lines. PMID:21188421

  3. Characterization of variation and quantitative trait loci related to terpenoid indole alkaloid yield in a recombinant inbred line mapping population of Catharanthus roseus

    Indian Academy of Sciences (India)

    Vishakha Sharma; Swati Chaudhary; Suchi Srivastava; Richa Pandey; Sushil Kumar

    2011-04-01

    Improved Catharanthus roseus cultivars are required for high yields of vinblastine, vindoline and catharanthine and/or serpentine and ajmalicine, the pharmaceutical terpenoid indole alkaloids. An approach to derive them is to map QTL for terpenoid indole alkaloids yields, identify DNA markers tightly linked to the QTL and apply marker assisted selection. Towards the end, 197 recombinant inbred lines from a cross were grown over two seasons to characterize variability for seven biomass and 23 terpenoid indole alkaloids content-traits and yield-traits. The recombinant inbred lines were genotyped for 178 DNA markers which formed a framework genetic map of eight linkage groups (LG), spanning 1786.5 cM, with 10.0 cM average intermarker distance. Estimates of correlations between traits allowed selection of seven relatively more important traits for terpenoid indole alkaloids yields. QTL analysis was performed on them using single marker (regression) analysis, simple interval mapping and composite interval mapping procedures. A total of 20 QTL were detected on five of eight LG, 10 for five traits on LG1, five for four traits on LG2, three for one trait on LG3 and one each for different traits on LG three and four. QTL for the same or different traits were found clustered on three LG. Co-location of two QTL for biomass traits was in accord of correlation between them. The QTL were validated for use in marker assisted selection by the recombinant inbred line which transgressively expressed 16 traits contributory to the yield vinblastine, vindoline and catharanthine from leaves and roots that possessed favourable alleles of 13 relevant QTL.

  4. Whole Body MRI at 3T with Quantitative Diffusion Weighted Imaging and Contrast-Enhanced Sequences for the Characterization of Peripheral Lesions in Patients with Neurofibromatosis Type 2 and Schwannomatosis

    International Nuclear Information System (INIS)

    Purpose. WB-MRI is mainly used for tumor detection and surveillance. The purpose of this study is to establish the feasibility of WB-MRI at 3T for lesion characterization, with DWI/ADC-mapping and contrast-enhanced sequences, in patients with neurofibromatosis type 2 (NF-2) and schwannomatosis. Materials and Methods. At 3T, WB-MRI was performed in 11 subjects (10 NF-2 and 1 schwannomatosis) with STIR, T1, contrast-enhanced T1, and DWI/ADC mapping (b = 50, 400, 800 s/mm2). Two readers reviewed imaging for the presence and character of peripheral lesions. Lesion size and features (signal intensity, heterogeneity, enhancement characteristics, and ADC values) were recorded. Descriptive statistics were reported. Results. Twenty-three lesions were identified, with average size of 4.6 ± 2.8 cm. Lesions were characterized as tumors (21/23) or cysts (2/23) by contrast-enhancement properties (enhancement in tumors, no enhancement in cysts). On T1, tumors were homogeneously isointense (5/21) or hypointense (16/21); on STIR, tumors were hyperintense and homogeneous (10/21) or heterogeneous (11/21); on postcontrast T1, tumors enhanced homogeneously (14/21) or heterogeneously (7/21); on DWI, tumor ADC values were variable (range 0.8–2.7), suggesting variability in intrinsic tumor properties. Conclusion. WB-MRI with quantitative DWI and contrast-enhanced sequences at 3T is feasible and advances the utility of WB-MRI not only to include detection, but also to provide additional metrics for lesion characterization

  5. Quantitative SPECT techniques.

    Science.gov (United States)

    Watson, D D

    1999-07-01

    Quantitative imaging involves first, a set of measurements that characterize an image. There are several variations of technique, but the basic measurements that are used for single photon emission computed tomography (SPECT) perfusion images are reasonably standardized. Quantification currently provides only relative tracer activity within the myocardial regions defined by an individual SPECT acquisition. Absolute quantification is still a work in progress. Quantitative comparison of absolute changes in tracer uptake comparing a stress and rest study or preintervention and postintervention study would be useful and could be done, but most commercial systems do not maintain the data normalization that is necessary for this. Measurements of regional and global function are now possible with electrocardiography (ECG) gating, and this provides clinically useful adjunctive data. Techniques for measuring ventricular function are evolving and promise to provide clinically useful accuracy. The computer can classify images as normal or abnormal by comparison with a normal database. The criteria for this classification involve more than just checking the normal limits. The images should be analyzed to measure how far they deviate from normal, and this information can be used in conjunction with pretest likelihood to indicate the level of statistical certainty that an individual patient has a true positive or true negative test. The interface between the computer and the clinician interpreter is an important part of the process. Especially when both perfusion and function are being determined, the ability of the interpreter to correctly assimilate the data is essential to the use of the quantitative process. As we become more facile with performing and recording objective measurements, the significance of the measurements in terms of risk evaluation, viability assessment, and outcome should be continually enhanced. PMID:10433336

  6. The clinical usefulness of extravascular lung water and pulmonary vascular permeability index to diagnose and characterize pulmonary edema: a prospective multicenter study on the quantitative differential diagnostic definition for acute lung injury/acute respiratory distress syndrome

    Science.gov (United States)

    2012-01-01

    Introduction Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is characterized by features other than increased pulmonary vascular permeability. Pulmonary vascular permeability combined with increased extravascular lung water content has been considered a quantitative diagnostic criterion of ALI/ARDS. This prospective, multi-institutional, observational study aimed to clarify the clinical pathophysiological features of ALI/ARDS and establish its quantitative diagnostic criteria. Methods The extravascular lung water index (EVLWI) and the pulmonary vascular permeability index (PVPI) were measured using the transpulmonary thermodilution method in 266 patients with PaO2/FiO2 ratio ≤ 300 mmHg and bilateral infiltration on chest radiography, in 23 ICUs of academic tertiary referral hospitals. Pulmonary edema was defined as EVLWI ≥ 10 ml/kg. Three experts retrospectively determined the pathophysiological features of respiratory insufficiency by considering the patients' history, clinical presentation, chest computed tomography and radiography, echocardiography, EVLWI and brain natriuretic peptide level, and the time course of all preceding findings under systemic and respiratory therapy. Results Patients were divided into the following three categories on the basis of the pathophysiological diagnostic differentiation of respiratory insufficiency: ALI/ARDS, cardiogenic edema, and pleural effusion with atelectasis, which were noted in 207 patients, 26 patients, and 33 patients, respectively. EVLWI was greater in ALI/ARDS and cardiogenic edema patients than in patients with pleural effusion with atelectasis (18.5 ± 6.8, 14.4 ± 4.0, and 8.3 ± 2.1, respectively; P < 0.01). PVPI was higher in ALI/ARDS patients than in cardiogenic edema or pleural effusion with atelectasis patients (3.2 ± 1.4, 2.0 ± 0.8, and 1.6 ± 0.5; P < 0.01). In ALI/ARDS patients, EVLWI increased with increasing pulmonary vascular permeability (r = 0.729, P < 0.01) and was weakly

  7. Validation and Characterization of Ghd7.1, a Major Quantitative Trait Locus with Pleiotropic Effects on Spikelets per Panicle, Plant Height, and Heading Date in Rice (Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    Touming Liu; Haiyang Liu; Huang Zhan; Yongzhong Xing

    2013-01-01

    A quantitative trait locus (QTL) that affects heading date (HD) and the number of spikelets per panicle (SPP) was previously identified in a small region on chromosome 7 in rice (Oryza sativa L.). In order to further characterize the QTL region, near isogenic lines (NILs) were quickly obtained by self-crossing recombinant inbred line 189, which is heterozygous in the vicinity of the target region. The pleiotropic effects of QTL Ghd7.1 on plant height (PH), SPP, and HD, were validated using an NIL-F2 population. Ghd7.1 explained 50.2%, 45.3%, and 76.9%of phenotypic variation in PH, SPP, and HD, respectively. Ghd7.1 was precisely mapped to a 357-kb region on the basis of analysis of the progeny of the NIL-F2 population. Day-length treatment confirmed that Ghd7.1 is sensitive to photoperiod, with long days delaying heading up to 12.5 d. Identification of panicle initiation and development for the pair of NILs showed that Ghd7.1 elongated the photoperiod-sensitive phase more than 10 d, but did not change the basic vegetative phase and the reproductive growth phase. These findings indicated that Ghd7.1 regulates SPP by controlling the rate of panicle differentiation rather than the duration of panicle development.

  8. Separation, characterization, and quantitation of process-related substances of the anti-hypertensive drug doxazosin mesylate by reversed-phase LC with PDA and ESI-MS as detectors.

    Science.gov (United States)

    Nageswara Rao, R; Nagaraju, D; Das, A K; Jena, Nivedita

    2007-02-01

    A simple and rapid reversed-phase liquid chromatography (LC) method with photodiode array (PDA) and electrospray ionization (ESI)-mass spectrometry (MS) as detectors was developed and validated to separate, identify, and quantitate the related substances of Doxazosin mesylate (DXZN) for monitoring the reactions involved during process development. The high-performance liquid chromatography profiles of related-substances of DXZN are used as fingerprints to follow the procedures used in the manufacturing units. The separation is accomplished on an Inertsil ODS-3 column with acetonitrile-ammonium acetate (10 mM, pH 4.0) as the mobile phase, using a gradient elution mode and monitoring the eluents by a photodiode array detector at 265 nm at ambient temperature. LC-ESI-MS-MS is used to identify the additional impurities formed during the synthesis. The identified impurities were synthesized and characterized by UV, Fourier transform-IR, 1H NMR, and MS data. The detection limits for the impurities are 0.74 - 4.14 x 10(-9) g, and the method is found to be suitable not only for the monitoring of synthetic reactions, but also for quality assurance of DXZN in bulk drugs and formulations.

  9. Some Quantitative Characterizations of Certain Symplectic Groups

    OpenAIRE

    M. Akbari; A. R. Moghaddamfar

    2013-01-01

    Given a finite group $G$, denote by ${\\rm D}(G)$ the degree pattern of $G$ and by ${\\rm OC}(G)$ the set of all order components of $G$. Denote by $h_{{\\rm OD}}(G)$ (resp. $h_{{\\rm OC}}(G)$) the number of isomorphism classes of finite groups $H$ satisfying conditions $|H|=|G|$ and ${\\rm D}(H)={\\rm D}(G)$ (resp. ${\\rm OC}(H)={\\rm OC}(G)$). A finite group $G$ is called OD-characterizable (resp. OC-characterizable) if $h_{\\rm OD}(G)=1$ (resp. $h_{\\rm OC}(G)=1$). Let $C=C_p(2)$ be a symplectic gro...

  10. Sugarcane starch: quantitative determination and characterization

    OpenAIRE

    Joelise de Alencar Figueira; Priscila Hoffmann Carvalho; Hélia Harumi Sato

    2011-01-01

    Starch is found in sugarcane as a storage polysaccharide. Starch concentrations vary widely depending on the country, variety, developmental stage, and growth conditions. The purpose of this study was to determine the starch content in different varieties of sugarcane, between May and November 2007, and some characteristics of sugarcane starch such as structure and granules size; gelatinization temperature; starch solution filterability; and susceptibility to glucoamylase, pullulanase, and co...

  11. Sugarcane starch: quantitative determination and characterization

    Directory of Open Access Journals (Sweden)

    Joelise de Alencar Figueira

    2011-09-01

    Full Text Available Starch is found in sugarcane as a storage polysaccharide. Starch concentrations vary widely depending on the country, variety, developmental stage, and growth conditions. The purpose of this study was to determine the starch content in different varieties of sugarcane, between May and November 2007, and some characteristics of sugarcane starch such as structure and granules size; gelatinization temperature; starch solution filterability; and susceptibility to glucoamylase, pullulanase, and commercial bacterial and fungal α-amylase enzymes. Susceptibility to debranching amylolytic isoamylase enzyme from Flavobacterium sp. was also tested. Sugarcane starch had spherical shape with a diameter of 1-3 µm. Sugarcane starch formed complexes with iodine, which showed greater absorption in the range of 540 to 620 nm. Sugarcane starch showed higher susceptibility to glucoamylase compared to that of waxy maize, cassava, and potato starch. Sugarcane starch also showed susceptibility to debranching amylolytic pullulanases similar to that of waxy rice starch. It also showed susceptibility to α-amylase from Bacillus subtilis, Bacillus licheniformis, and Aspergillus oryzae similar to that of the other tested starches producing glucose, maltose, maltotriose, maltotetraose, maltopentose and limit α- dextrin.

  12. Quantitative lithofacies palaeogeography

    Institute of Scientific and Technical Information of China (English)

    Zeng-Zhao; Feng; Xiu-Juan; Zheng; Zhi-Dong; Bao; Zhen-Kui; Jin; Sheng-He; Wu; You-Bin; He; Yong-Min; Peng; Yu-Qing; Yang; Jia-Qiang; Zhang; Yong-Sheng; Zhang

    2014-01-01

    Quantitative lithofacies palaeogeography is an important discipline of palaeogeography.It is developed on the foundation of traditional lithofacies palaeogeography and palaeogeography,the core of which is the quantitative lithofacies palaeogeographic map.Quantity means that in the palaeogeographic map,the division and identification of each palaeogeographic unit are supported by quantitative data and quantitative fundamental maps.Our lithofacies palaeogeographic maps are quantitative or mainly quantitative.A great number of quantitative lithofacies palaeogeographic maps have been published,and articles and monographs of quantitative lithofacies palaeogeography have been published successively,thus the quantitative lithofacies palaeogeography was formed and established.It is an important development in lithofacies palaeogeography.In composing quantitative lithofacies palaeogeographic maps,the key measure is the single factor analysis and multifactor comprehensive mapping method—methodology of quantitative lithofacies palaeogeography.In this paper,the authors utilize two case studies,one from the Early Ordovician of South China and the other from the Early Ordovician of Ordos,North China,to explain how to use this methodology to compose the quantitative lithofacies palaeogeographic maps,and to discuss the palaeogeographic units in these maps.Finally,three characteristics,i.e.,quantification,multiple orders and multiple types,of quantitative lithofacies palaeogeographic maps are conclusively discussed.

  13. Quantitative investment analysis

    CERN Document Server

    DeFusco, Richard

    2007-01-01

    In the "Second Edition" of "Quantitative Investment Analysis," financial experts Richard DeFusco, Dennis McLeavey, Jerald Pinto, and David Runkle outline the tools and techniques needed to understand and apply quantitative methods to today's investment process.

  14. Rigour in quantitative research.

    Science.gov (United States)

    Claydon, Leica Sarah

    2015-07-22

    This article which forms part of the research series addresses scientific rigour in quantitative research. It explores the basis and use of quantitative research and the nature of scientific rigour. It examines how the reader may determine whether quantitative research results are accurate, the questions that should be asked to determine accuracy and the checklists that may be used in this process. Quantitative research has advantages in nursing, since it can provide numerical data to help answer questions encountered in everyday practice.

  15. Quantitative phase imaging of arthropods

    Science.gov (United States)

    Sridharan, Shamira; Katz, Aron; Soto-Adames, Felipe; Popescu, Gabriel

    2015-01-01

    Abstract. Classification of arthropods is performed by characterization of fine features such as setae and cuticles. An unstained whole arthropod specimen mounted on a slide can be preserved for many decades, but is difficult to study since current methods require sample manipulation or tedious image processing. Spatial light interference microscopy (SLIM) is a quantitative phase imaging (QPI) technique that is an add-on module to a commercial phase contrast microscope. We use SLIM to image a whole organism springtail Ceratophysella denticulata mounted on a slide. This is the first time, to our knowledge, that an entire organism has been imaged using QPI. We also demonstrate the ability of SLIM to image fine structures in addition to providing quantitative data that cannot be obtained by traditional bright field microscopy. PMID:26334858

  16. Quantitative phase imaging of arthropods

    Science.gov (United States)

    Sridharan, Shamira; Katz, Aron; Soto-Adames, Felipe; Popescu, Gabriel

    2015-11-01

    Classification of arthropods is performed by characterization of fine features such as setae and cuticles. An unstained whole arthropod specimen mounted on a slide can be preserved for many decades, but is difficult to study since current methods require sample manipulation or tedious image processing. Spatial light interference microscopy (SLIM) is a quantitative phase imaging (QPI) technique that is an add-on module to a commercial phase contrast microscope. We use SLIM to image a whole organism springtail Ceratophysella denticulata mounted on a slide. This is the first time, to our knowledge, that an entire organism has been imaged using QPI. We also demonstrate the ability of SLIM to image fine structures in addition to providing quantitative data that cannot be obtained by traditional bright field microscopy.

  17. QUANTITATIVE CONFOCAL LASER SCANNING MICROSCOPY

    Directory of Open Access Journals (Sweden)

    Merete Krog Raarup

    2011-05-01

    Full Text Available This paper discusses recent advances in confocal laser scanning microscopy (CLSM for imaging of 3D structure as well as quantitative characterization of biomolecular interactions and diffusion behaviour by means of one- and two-photon excitation. The use of CLSM for improved stereological length estimation in thick (up to 0.5 mm tissue is proposed. The techniques of FRET (Fluorescence Resonance Energy Transfer, FLIM (Fluorescence Lifetime Imaging Microscopy, FCS (Fluorescence Correlation Spectroscopy and FRAP (Fluorescence Recovery After Photobleaching are introduced and their applicability for quantitative imaging of biomolecular (co-localization and trafficking in live cells described. The advantage of two-photon versus one-photon excitation in relation to these techniques is discussed.

  18. Directional and quantitative phosphorylation networks

    DEFF Research Database (Denmark)

    Jørgensen, Claus; Linding, Rune

    2008-01-01

    for unravelling phosphorylation-mediated cellular interaction networks. In particular, we will discuss how the combination of new quantitative mass-spectrometric technologies and computational algorithms together are enhancing mapping of these largely uncharted dynamic networks. By combining quantitative......Directionality in protein signalling networks is due to modulated protein-protein interactions and is fundamental for proper signal progression and response to external and internal cues. This property is in part enabled by linear motifs embedding post-translational modification sites. These serve...... as recognition sites, guiding phosphorylation by kinases and subsequent binding of modular domains (e.g. SH2 and BRCT). Characterization of such modification-modulated interactions on a proteome-wide scale requires extensive computational and experimental analysis. Here, we review the latest advances in methods...

  19. Quantitative analysis chemistry

    International Nuclear Information System (INIS)

    This book is about quantitative analysis chemistry. It is divided into ten chapters, which deal with the basic conception of material with the meaning of analysis chemistry and SI units, chemical equilibrium, basic preparation for quantitative analysis, introduction of volumetric analysis, acid-base titration of outline and experiment examples, chelate titration, oxidation-reduction titration with introduction, titration curve, and diazotization titration, precipitation titration, electrometric titration and quantitative analysis.

  20. Delineation of concentration ranges and longitudinal changes of human plasma protein variants.

    Directory of Open Access Journals (Sweden)

    Olgica Trenchevska

    Full Text Available Human protein diversity arises as a result of alternative splicing, single nucleotide polymorphisms (SNPs and posttranslational modifications. Because of these processes, each protein can exists as multiple variants in vivo. Tailored strategies are needed to study these protein variants and understand their role in health and disease. In this work we utilized quantitative mass spectrometric immunoassays to determine the protein variants concentration of beta-2-microglobulin, cystatin C, retinol binding protein, and transthyretin, in a population of 500 healthy individuals. Additionally, we determined the longitudinal concentration changes for the protein variants from four individuals over a 6 month period. Along with the native forms of the four proteins, 13 posttranslationally modified variants and 7 SNP-derived variants were detected and their concentration determined. Correlations of the variants concentration with geographical origin, gender, and age of the individuals were also examined. This work represents an important step toward building a catalog of protein variants concentrations and examining their longitudinal changes.

  1. Development and Characterization of Probe-Based Real Time Quantitative RT-PCR Assays for Detection and Serotyping of Foot-And-Mouth Disease Viruses Circulating in West Eurasia.

    Directory of Open Access Journals (Sweden)

    Syed M Jamal

    Full Text Available Rapid and accurate diagnosis of foot-and-mouth disease (FMD and virus serotyping are of paramount importance for control of this disease in endemic areas where vaccination is practiced. Ideally this virus characterization should be achieved without the need for virus amplification in cell culture. Due to the heterogeneity of FMD viruses (FMDVs in different parts of the world, region specific diagnostic tests are required. In this study, hydrolysable probe-based real time reverse transcription quantitative polymerase chain reaction (RT-qPCR assays were developed for specific detection and serotyping of the FMDVs currently circulating in West Eurasia. These assays were evaluated, in parallel with pan-FMDV diagnostic assays and earlier serotype-specific assays, using field samples originating from Pakistan and Afghanistan containing FMD viruses belonging to different sublineages of O-PanAsia, A-Iran05 and Asia-1 (Group-II and Group-VII (Sindh-08. In addition, field samples from Iran and Bulgaria, containing FMDVs belonging to the O-PanAsiaANT-10 sublineage were also tested. Each of the three primer/probe sets was designed to be specific for just one of the serotypes O, A and Asia-1 of FMDV and detected the RNA from the target viruses with cycle threshold (CT values comparable with those obtained with the serotype-independent pan-FMDV diagnostic assays. No cross-reactivity was observed in these assays between the heterotypic viruses circulating in the region. The assays reported here have higher diagnostic sensitivity (100% each for serotypes O and Asia-1, and 92% [95% CI = 81.4-100%] for serotype A positive samples and specificity (100% each for serotypes O, A and Asia-1 positive samples for the viruses currently circulating in West Eurasia compared to the serotyping assays reported earlier. Comparisons of the sequences of the primers and probes used in these assays and the corresponding regions of the circulating viruses provided explanations for

  2. On Quantitative Rorschach Scales.

    Science.gov (United States)

    Haggard, Ernest A.

    1978-01-01

    Two types of quantitative Rorschach scales are discussed: first, those based on the response categories of content, location, and the determinants, and second, global scales based on the subject's responses to all ten stimulus cards. (Author/JKS)

  3. Digital radiography: a quantitative approach

    Energy Technology Data Exchange (ETDEWEB)

    Retraint, F. [Universite de Technologie de Troyes, Troyes (France)

    2004-07-01

    'Full-text:' In a radiograph the value of each pixel is related to the material thickness crossed by the x-rays. Using this relationship, an object can be characterized by parameters such as depth, surface and volume. Assuming a locally linear detector response and using a radiograph of reference object, the quantitative thickness map of object can be obtained by applying offset and gain corrections. However, for an acquisition system composed of cooled CCD camera optically coupled to a scintillator screen, the radiographic image formation process generates some bias which prevent from obtaining the quantitative information: non uniformity of the x-ray source, beam hardening, Compton scattering, scintillator screen, optical system response. In a first section, we propose a complete model of the radiographic image formation process taking account of these biases. In a second section, we present an inversion scheme of this model for a single material object, which enables to obtain the thickness map of the object crossed by the x-rays. (author)

  4. Quantitative Decision Support Requires Quantitative User Guidance

    Science.gov (United States)

    Smith, L. A.

    2009-12-01

    Is it conceivable that models run on 2007 computer hardware could provide robust and credible probabilistic information for decision support and user guidance at the ZIP code level for sub-daily meteorological events in 2060? In 2090? Retrospectively, how informative would output from today’s models have proven in 2003? or the 1930’s? Consultancies in the United Kingdom, including the Met Office, are offering services to “future-proof” their customers from climate change. How is a US or European based user or policy maker to determine the extent to which exciting new Bayesian methods are relevant here? or when a commercial supplier is vastly overselling the insights of today’s climate science? How are policy makers and academic economists to make the closely related decisions facing them? How can we communicate deep uncertainty in the future at small length-scales without undermining the firm foundation established by climate science regarding global trends? Three distinct aspects of the communication of the uses of climate model output targeting users and policy makers, as well as other specialist adaptation scientists, are discussed. First, a brief scientific evaluation of the length and time scales at which climate model output is likely to become uninformative is provided, including a note on the applicability the latest Bayesian methodology to current state-of-the-art general circulation models output. Second, a critical evaluation of the language often employed in communication of climate model output, a language which accurately states that models are “better”, have “improved” and now “include” and “simulate” relevant meteorological processed, without clearly identifying where the current information is thought to be uninformative and misleads, both for the current climate and as a function of the state of the (each) climate simulation. And thirdly, a general approach for evaluating the relevance of quantitative climate model output

  5. Quantitative Compositional Reasoning

    NARCIS (Netherlands)

    Chatterjee, K.; Alfaro, de L.; Faella, M.; Henzinger, T.A.; Majumdar, R.; Stoelinga, M.I.A.

    2006-01-01

    We present a compositional theory of system verifica tion, where specifications assign real-numbered costs to systems. These costs can express a wide variety of quantitative system properties, such as resource consumption, price or a measure of how well a system satisfies its specification. The theo

  6. Critical Quantitative Inquiry in Context

    Science.gov (United States)

    Stage, Frances K.; Wells, Ryan S.

    2014-01-01

    This chapter briefly traces the development of the concept of critical quantitative inquiry, provides an expanded conceptualization of the tasks of critical quantitative research, offers theoretical explanation and justification for critical research using quantitative methods, and previews the work of quantitative criticalists presented in this…

  7. Non destructive testing of industrial pieces by radiography: quantitative characterization and 3 D reconstruction by the way of a limited number of images; Controle non destructif de pieces industrielles par radiographie: caracterisation quantitative et reconstruction 3D a partir d`un nombre limite de vues

    Energy Technology Data Exchange (ETDEWEB)

    Retraint, F

    1998-12-31

    The non destructive testing of industrial pieces is evaluated on the basis of numerical radiographies.The context of the study is the online control of the fuel rods production. A direct model of a numerical radiography formation is proposed and detailed for an acquisition system consisting of a CCD video connected to a converter screen by an optical system. As this approach does not allow the determination of the measured matter thickness from the X-ray photograph, an approximate model based on realistic approximations of the industrial non destructive testing, has been developed. For the specific cases it is possible to inverse the model and to reach the quantitative information present in the x-ray photograph, in other words, the map of the X-rays measured matter thickness. It becomes then possible to access to the quantitative parameters of the possible defects present in the measured specimen, such as the surface and the bulk. To reach the 3 D information on the defects a 3 D reconstruction method, from 3 X-rays photographs, is proposed.The inverse problem is solved by the non convex energy minimization. (A.L.B.) 109 refs.

  8. Characterization of copy numbers of 16S rDNA and 16S rRNA of Candidatus Liberibacter asiaticus and the implication in detection in planta using quantitative PCR

    Directory of Open Access Journals (Sweden)

    Wang Nian

    2009-03-01

    Full Text Available Abstract Background Citrus Huanglongbing (HLB is one of the most devastating diseases on citrus and is associated with Candidatus Liberibacter spp.. The pathogens are phloem limited and have not been cultured in vitro. The current management strategy of HLB is to remove infected citrus trees and reduce psyllid populations with insecticides to prevent the spreading. This strategy requires sensitive and reliable diagnostic methods for early detection. Results We investigated the copy numbers of the 16S rDNA and 16S rRNA of the HLB pathogen and the implication of improving the diagnosis of HLB for early detection using Quantitative PCR. We compared the detection of HLB with different Quantitative PCR based methods with primers/probe targeting either 16S rDNA, beta-operon DNA, 16S rRNA, or beta-operon RNA. The 16S rDNA copy number of Ca. Liberibacter asiaticus was estimated to be three times of that of the beta-operon region, thus allowing detection of lower titer of Ca. L. asiaticus. Quantitative reverse transcriptional PCR (QRT-PCR indicated that the 16S rRNA averaged 7.83 times more than that of 16S rDNA for the same samples. Dilution analysis also indicates that QRT-PCR targeting 16S rRNA is 10 time more sensitive than QPCR targeting 16S rDNA. Thus QRT-PCR was able to increase the sensitivity of detection by targeting 16S rRNA. Conclusion Our result indicates that Candidatus Liberibacter asiaticus contains three copies of 16S rDNA. The copy number of 16S rRNA of Ca. L. asiaticus in planta averaged about 7.8 times of 16S rDNA for the same set of samples tested in this study. Detection sensitivity of HLB could be improved through the following approaches: using 16S rDNA based primers/probe in the QPCR assays; and using QRT-PCR assays targeting 16S rRNA.

  9. Quantitative social science

    Science.gov (United States)

    Weidlich, W.

    1987-03-01

    General concepts for the quantitative description of the dynamics of social processes are introduced. They allow for embedding social science into the conceptual framework of synergetics. Equations of motion for the socioconfiguration are derived on the stochastic and quasideterministic level. As an application the migration of interacting human populations is treated. The solutions of the nonlinear migratory equations include limit cycles and strange attractors. The empiric evaluation of interregional migratory dynamics is exemplified in the case of Germany.

  10. Quantitative FDG in depression

    International Nuclear Information System (INIS)

    Full text: Studies of regional cerebral glucose metabolism (rCMRGlu) using positron emission tomography (PET) in patients with affective disorders have consistently demonstrated reduced metabolism in the frontal regions. Different quantitative and semi-quantitative rCMRGlu regions of interest (ROI) comparisons, e.g. absolute metabolic rates, ratios of dorsolateral prefrontal cortex (DLPFC) to ipsilateral hemisphere cortex, have been reported. These studies suffered from the use of a standard brain atlas to define ROls, whereas in this case study, the individual''s magnetic resonance imaging (MRI) scan was registered with the PET scan to enable accurate neuroanatomical ROI definition for the subject. The patient is a 36-year-old female with a six-week history of major depression (HAM-D = 34, MMSE = 28). A quantitative FDG PET study and an MRI scan were performed. Six MRI-guided ROls (DLPFC, PFC, whole hemisphere) were defined. The average rCMRGlu in the DLPFC (left = 28.8 + 5.8 mol/100g/min; right = 25.6 7.0 mol/100g/min) were slightly reduced compared to the ipsilateral hemispherical rate (left = 30.4 6.8 mol/100g/min; right = 29.5 7.2 mol/100g/min). The ratios of DLPFC to ipsilateral hemispheric rate were close to unity (left = 0.95 0.29; right 0.87 0.32). The right to left DLPFC ratio did not show any significant asymmetry (0.91 0.30). These results do not correlate with earlier published results reporting decreased left DLPFC rates compared to right DLPFC, although our results will need to be replicated with a group of depressed patients. Registration of PET and MRI studies is necessary in ROI-based quantitative FDG PET studies to allow for the normal anatomical variation among individuals, and thus is essential for accurate comparison of rCMRGlu between individuals

  11. Suitability of thin-layer chromatography-flame ionization detection with regard to quantitative characterization of different fossil fuel products. 1. FID performances and response of pure compounds related to fossil fuel products

    Energy Technology Data Exchange (ETDEWEB)

    Cebolla, V.L.; Vela, J.; Membrado, L.; Ferrando, A.C. [CSIC, Zaragoza (Spain). Inst. de Carboquimica, Dept. de Procesos Quimicos

    1998-10-01

    The performance of a modern TLC-FID system (which includes the newest detector configuration) was tested on polycyclic aromatic compound standards and related compounds as a preliminary step to evaluate its suitability for quantitative hydrocarbon group type analysis of different coal and petroleum products. FID linearity was evaluated as a function of sample load and scan speed for high-molecular-weight and semi-volatile standards. TLC-FID response factors for compounds of several homologous series were studied in order to differentiate effects of volatility from those exclusively due to the chemical nature concerning FID response. Criteria are developed for the accurate application of TLC-FID to fossil fuel samples. Measurements of chromarod temperatures were carried out in order to evaluate whether an evaporation of compounds outside the H{sub 2} flame might take place. 10 refs., 3 figs., 4 tabs.

  12. Development and Characterization of Probe-Based Real Time Quantitative RT-PCR Assays for Detection and Serotyping of Foot-And-Mouth Disease Viruses Circulating in West Eurasia

    DEFF Research Database (Denmark)

    Jamal, Syed M.; Belsham, Graham

    2015-01-01

    . Due to the heterogeneity of FMD viruses (FMDVs) in different parts of the world, region specific diagnostic tests are required. In this study, hydrolysableprobe-based real time reverse transcription quantitative polymerase chain reaction (RTqPCR) assays were developed for specific detection...... and serotyping of the FMDVs currently circulating in West Eurasia. These assays were evaluated, in parallel with pan-FMDV diagnosticassays and earlier serotype-specific assays, using field samples originating from Pakistan and Afghanistan containing FMD viruses belonging to different sublineages of OPan...... and detected the RNA from the targetviruses with cycle threshold (CT) values comparable with those obtained with the serotype independentpan-FMDV diagnostic assays. No cross-reactivity was observed in the seassays between the heterotypic viruses circulating in the region. The assays reported here have higher...

  13. Highly efficient, selective, sensitive and stability indicating RP-HPLC-UV method for the quantitative determination of potential impurities and characterization of four novel impurities in eslicarbazepine acetate active pharmaceutical ingredient by LC/ESI-IT/MS/MS.

    Science.gov (United States)

    Thomas, Saji; Bharti, Amber; Maddhesia, Pawan Kumar; Shandilya, Sanjeev; Agarwal, Ashutosh; Dharamvir; Biswas, Sujay; Bhansal, Vikas; Gupta, Ashish Kumar; Tewari, Praveen Kumar; Mathela, Chandra S

    2012-03-01

    A novel, sensitive, selective and stability indicating LC-UV method was developed for the determination of potential impurities of eslicarbazepine acetate. High performance liquid chromatographic investigation of eslicarbazepine acetate laboratory sample revealed the presence of several impurities. Three impurities were characterized rapidly and four impurities were found to be unknown. The unknown impurities were identified by liquid chromatography coupled with electrospray ionization, ion trap mass spectrometry (LC/ESI-IT/MS/MS). Structural confirmation of these impurities was unambiguously carried out by synthesis followed by characterization using nuclear magnetic resonance spectroscopy (NMR), infrared spectroscopy (FT-IR) and mass spectrometry (MS). Based on the spectroscopic, spectrometric and elemental analysis data unknown impurities were characterized as 5-acetyl-5,11-dihydro-10H-dibenzo [b,f]azepin-10-one, N-acetyl-5H-dibenzo[b,f]azepine-5-carboxamide, 5-acetyl-10,11-dihydro-5H-dibenzo[b,f]azepin-10-yl acetate and 5-acetyl-5H-dibenzo[b,f]azepin-10-yl acetate. The newly developed LC-UV method was validated according to ICH guidelines considering eleven potential impurities and four new impurities to demonstrate specificity, precision, linearity, accuracy and stability indicating nature of the method. The newly developed method was found to be highly efficient, selective, sensitive and stability indicating. A plausible pathway for the formation of four new impurities is proposed. PMID:22178334

  14. The effect of metabolic regulation on microvascular permeability to small and large molecules in short-term juvenile diabetics

    DEFF Research Database (Denmark)

    Parving, H H; Noer, Ivan; Deckert, Toke;

    1976-01-01

    of albumin (TER), glomerular filtration rate (GFR), capillary filtration coefficient (CFC), and capillary diffusion capacity (CDC). The urinary albumin and beta2-microglobulin concentration were measured by sensitive radioimmunoassays; TER was detemined from the initial disappearance of intravenously......The microvascular permeability to small and large molecules was studied during good and poor metabolic regulation in ten short duration juvenile diabetics. The following variables were measured; daily urinary albumin and beta2-microglobulin-excretion rates, whole body transcapillary escape rate...

  15. F# for quantitative finance

    CERN Document Server

    Astborg, Johan

    2013-01-01

    To develop your confidence in F#, this tutorial will first introduce you to simpler tasks such as curve fitting. You will then advance to more complex tasks such as implementing algorithms for trading semi-automation in a practical scenario-based format.If you are a data analyst or a practitioner in quantitative finance, economics, or mathematics and wish to learn how to use F# as a functional programming language, this book is for you. You should have a basic conceptual understanding of financial concepts and models. Elementary knowledge of the .NET framework would also be helpful.

  16. Whole Body MRI at 3T with Quantitative Diffusion Weighted Imaging and Contrast-Enhanced Sequences for the Characterization of Peripheral Lesions in Patients with Neurofibromatosis Type 2 and Schwannomatosis

    OpenAIRE

    Fayad, Laura M.; Blakeley, Jaishri; Plotkin, Scott; Widemann, Brigitte; Jacobs, Michael A.

    2013-01-01

    Purpose. WB-MRI is mainly used for tumor detection and surveillance. The purpose of this study is to establish the feasibility of WB-MRI at 3T for lesion characterization, with DWI/ADC-mapping and contrast-enhanced sequences, in patients with neurofibromatosis type 2 (NF-2) and schwannomatosis. Materials and Methods. At 3T, WB-MRI was performed in 11 subjects (10 NF-2 and 1 schwannomatosis) with STIR, T1, contrast-enhanced T1, and DWI/ADC mapping (b = 50, 400, 800 s/mm2). Two readers reviewed...

  17. Quantitative Seismic Amplitude Analysis

    NARCIS (Netherlands)

    Dey, A.K.

    2011-01-01

    The Seismic Value Chain quantifies the cyclic interaction between seismic acquisition, imaging and reservoir characterization. Modern seismic innovation to address the global imbalance in hydrocarbon supply and demand requires such cyclic interaction of both feed-forward and feed-back processes. Cur

  18. Quantitative analysis and morphological characterization of 6063 alloy. Microstructural and mechanical comparison between periphery and center of semi-continuous casting round billets; Analisis cuantitativo y caracterizacion morfologica de la aleacion 6063. Diferencias microestructurales y mecanicas entre la superficie y el nucleo de barras cilindricas de colada semicontinua

    Energy Technology Data Exchange (ETDEWEB)

    Asensio-Lozano, J.; Suarez-Pena, B.

    2012-11-01

    In the present work it has been studied the effect of microstructure on tensile properties of semi-continuously cast round billets manufactured in the industrial 6063 alloy either in the as cast state or after heat treatment. Relevant microstructural features were characterized by quantitative metallographic techniques, both in the periphery and centre of billets, and contrasted against the measured tensile properties at room temperature. Special attention in the study was paid to the way in which chemical non-homogeneities could be minimized. For such purpose the refinement and shape modification of second phase particles formed during solidification, thereafter transformed during the subsequent industrial heat treatment, were assessed. It was observed that the morphology of iron-rich intermetallic compounds developed during solidification was highly influenced by the solidification rate as seen in the billet cross section. It was also verified that the optimal elongation corresponded to the central portion of the billet once industrially homogenized. (Author) 50 refs.

  19. Quantitative velocity modulation spectroscopy

    Science.gov (United States)

    Hodges, James N.; McCall, Benjamin J.

    2016-05-01

    Velocity Modulation Spectroscopy (VMS) is arguably the most important development in the 20th century for spectroscopic study of molecular ions. For decades, interpretation of VMS lineshapes has presented challenges due to the intrinsic covariance of fit parameters including velocity modulation amplitude, linewidth, and intensity. This limitation has stifled the growth of this technique into the quantitative realm. In this work, we show that subtle changes in the lineshape can be used to help address this complexity. This allows for determination of the linewidth, intensity relative to other transitions, velocity modulation amplitude, and electric field strength in the positive column of a glow discharge. Additionally, we explain the large homogeneous component of the linewidth that has been previously described. Using this component, the ion mobility can be determined.

  20. Quantitative Concept Analysis

    CERN Document Server

    Pavlovic, Dusko

    2012-01-01

    Formal Concept Analysis (FCA) begins from a context, given as a binary relation between some objects and some attributes, and derives a lattice of concepts, where each concept is given as a set of objects and a set of attributes, such that the first set consists of all objects that satisfy all attributes in the second, and vice versa. Many applications, though, provide contexts with quantitative information, telling not just whether an object satisfies an attribute, but also quantifying this satisfaction. Contexts in this form arise as rating matrices in recommender systems, as occurrence matrices in text analysis, as pixel intensity matrices in digital image processing, etc. Such applications have attracted a lot of attention, and several numeric extensions of FCA have been proposed. We propose the framework of proximity sets (proxets), which subsume partially ordered sets (posets) as well as metric spaces. One feature of this approach is that it extracts from quantified contexts quantified concepts, and thu...

  1. Quantitative metamaterial property extraction

    CERN Document Server

    Schurig, David

    2015-01-01

    We examine an extraction model for metamaterials, not previously reported, that gives precise, quantitative and causal representation of S parameter data over a broad frequency range, up to frequencies where the free space wavelength is only a modest factor larger than the unit cell dimension. The model is comprised of superposed, slab shaped response regions of finite thickness, one for each observed resonance. The resonance dispersion is Lorentzian and thus strictly causal. This new model is compared with previous models for correctness likelihood, including an appropriate Occam's factor for each fit parameter. We find that this new model is by far the most likely to be correct in a Bayesian analysis of model fits to S parameter simulation data for several classic metamaterial unit cells.

  2. Herbs and spices: characterization and quantitation of biologically-active markers for routine quality control by multiple headspace solid-phase microextraction combined with separative or non-separative analysis.

    Science.gov (United States)

    Sgorbini, Barbara; Bicchi, Carlo; Cagliero, Cecilia; Cordero, Chiara; Liberto, Erica; Rubiolo, Patrizia

    2015-01-01

    Herbs and spices are used worldwide as food flavoring, thus determination of their identity, origin, and quality is mandatory for safe human consumption. An analysis strategy based on separative (HS-SPME-GC-MS) and non-separative (HS-SPME-MS) approaches is proposed for the volatile fraction of herbs and spices, for quality control and to quantify the aromatic markers with a single analysis directly on the plant material as such. Eight-to-ten lots of each of the following herbs/spices were considered: cloves (Syzygium aromaticum (L.) Merr. & Perry), American peppertree (Schinus molle L.), black pepper and white pepper (Piper nigrum L.), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.) and thyme (Thymus vulgaris L.). Homogeneity, origin, and chemotypes of the investigated lots of each herb/spice were defined by fingerprinting, through statistical elaboration with principal component analysis (PCA). Characterizing aromatic markers were directly quantified on the solid matrix through multiple headspace extraction-HS-SPME (MHS-SPME). Reliable results were obtained with both separative and non-separative methods (where the latter were applicable); the two were in full agreement, RSD% ranging from 1.8 to 7.7% for eugenol in cloves, 2.2-18.4% for carvacrol+thymol in thyme, and 3.1-16.8% for thujones in sage. PMID:25541091

  3. Herbs and spices: characterization and quantitation of biologically-active markers for routine quality control by multiple headspace solid-phase microextraction combined with separative or non-separative analysis.

    Science.gov (United States)

    Sgorbini, Barbara; Bicchi, Carlo; Cagliero, Cecilia; Cordero, Chiara; Liberto, Erica; Rubiolo, Patrizia

    2015-01-01

    Herbs and spices are used worldwide as food flavoring, thus determination of their identity, origin, and quality is mandatory for safe human consumption. An analysis strategy based on separative (HS-SPME-GC-MS) and non-separative (HS-SPME-MS) approaches is proposed for the volatile fraction of herbs and spices, for quality control and to quantify the aromatic markers with a single analysis directly on the plant material as such. Eight-to-ten lots of each of the following herbs/spices were considered: cloves (Syzygium aromaticum (L.) Merr. & Perry), American peppertree (Schinus molle L.), black pepper and white pepper (Piper nigrum L.), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.) and thyme (Thymus vulgaris L.). Homogeneity, origin, and chemotypes of the investigated lots of each herb/spice were defined by fingerprinting, through statistical elaboration with principal component analysis (PCA). Characterizing aromatic markers were directly quantified on the solid matrix through multiple headspace extraction-HS-SPME (MHS-SPME). Reliable results were obtained with both separative and non-separative methods (where the latter were applicable); the two were in full agreement, RSD% ranging from 1.8 to 7.7% for eugenol in cloves, 2.2-18.4% for carvacrol+thymol in thyme, and 3.1-16.8% for thujones in sage.

  4. Quantitative Characterization of E-selectin Interaction with Native CD44 and P-selectin Glycoprotein Ligand-1 (PSGL-1) Using a Real Time Immunoprecipitation-based Binding Assay

    KAUST Repository

    Abu Samra, Dina Bashir Kamil

    2015-06-29

    Selectins (E-, P-, and L-selectins) interact with glycoprotein ligands to mediate the essential tethering/rolling step in cell transport and delivery that captures migrating cells from the circulating flow. In this work, we developed a real time immunoprecipitation assay on a surface plasmon resonance chip that captures native glycoforms of two well known E-selectin ligands (CD44/hematopoietic cell E-/L-selectin ligand and P-selectin glycoprotein ligand-1) from hematopoietic cell extracts. Here we present a comprehensive characterization of their binding to E-selectin. We show that both ligands bind recombinant monomeric E-selectin transiently with fast on- and fast off-rates, whereas they bind dimeric E-selectin with remarkably slow onand off-rates. This binding requires the sialyl Lewis x sugar moiety to be placed on both O- and N-glycans, and its association, but not dissociation, is sensitive to the salt concentration. Our results suggest a mechanism through which monomeric selectins mediate initial fast on and fast off kinetics to help capture cells out of the circulating shear flow; subsequently, tight binding by dimeric/oligomeric selectins is enabled to significantly slow rolling. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Programmable Quantitative DNA Nanothermometers.

    Science.gov (United States)

    Gareau, David; Desrosiers, Arnaud; Vallée-Bélisle, Alexis

    2016-07-13

    Developing molecules, switches, probes or nanomaterials that are able to respond to specific temperature changes should prove of utility for several applications in nanotechnology. Here, we describe bioinspired strategies to design DNA thermoswitches with programmable linear response ranges that can provide either a precise ultrasensitive response over a desired, small temperature interval (±0.05 °C) or an extended linear response over a wide temperature range (e.g., from 25 to 90 °C). Using structural modifications or inexpensive DNA stabilizers, we show that we can tune the transition midpoints of DNA thermometers from 30 to 85 °C. Using multimeric switch architectures, we are able to create ultrasensitive thermometers that display large quantitative fluorescence gains within small temperature variation (e.g., > 700% over 10 °C). Using a combination of thermoswitches of different stabilities or a mix of stabilizers of various strengths, we can create extended thermometers that respond linearly up to 50 °C in temperature range. Here, we demonstrate the reversibility, robustness, and efficiency of these programmable DNA thermometers by monitoring temperature change inside individual wells during polymerase chain reactions. We discuss the potential applications of these programmable DNA thermoswitches in various nanotechnology fields including cell imaging, nanofluidics, nanomedecine, nanoelectronics, nanomaterial, and synthetic biology. PMID:27058370

  6. Quantitative Electron Nanodiffraction.

    Energy Technology Data Exchange (ETDEWEB)

    Spence, John [Arizona State Univ., Mesa, AZ (United States)

    2015-01-30

    This Final report summarizes progress under this award for the final reporting period 2002 - 2013 in our development of quantitive electron nanodiffraction to materials problems, especially devoted to atomistic processes in semiconductors and electronic oxides such as the new artificial oxide multilayers, where our microdiffraction is complemented with energy-loss spectroscopy (ELNES) and aberration-corrected STEM imaging (9). The method has also been used to map out the chemical bonds in the important GaN semiconductor (1) used for solid state lighting, and to understand the effects of stacking sequence variations and interfaces in digital oxide superlattices (8). Other projects include the development of a laser-beam Zernike phase plate for cryo-electron microscopy (5) (based on the Kapitza-Dirac effect), work on reconstruction of molecular images using the scattering from many identical molecules lying in random orientations (4), a review article on space-group determination for the International Tables on Crystallography (10), the observation of energy-loss spectra with millivolt energy resolution and sub-nanometer spatial resolution from individual point defects in an alkali halide, a review article for the Centenary of X-ray Diffration (17) and the development of a new method of electron-beam lithography (12). We briefly summarize here the work on GaN, on oxide superlattice ELNES, and on lithography by STEM.

  7. Quantitive DNA Fiber Mapping

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Chun-Mei; Wang, Mei; Greulich-Bode, Karin M.; Weier, Jingly F.; Weier, Heinz-Ulli G.

    2008-01-28

    Several hybridization-based methods used to delineate single copy or repeated DNA sequences in larger genomic intervals take advantage of the increased resolution and sensitivity of free chromatin, i.e., chromatin released from interphase cell nuclei. Quantitative DNA fiber mapping (QDFM) differs from the majority of these methods in that it applies FISH to purified, clonal DNA molecules which have been bound with at least one end to a solid substrate. The DNA molecules are then stretched by the action of a receding meniscus at the water-air interface resulting in DNA molecules stretched homogeneously to about 2.3 kb/{micro}m. When non-isotopically, multicolor-labeled probes are hybridized to these stretched DNA fibers, their respective binding sites are visualized in the fluorescence microscope, their relative distance can be measured and converted into kilobase pairs (kb). The QDFM technique has found useful applications ranging from the detection and delineation of deletions or overlap between linked clones to the construction of high-resolution physical maps to studies of stalled DNA replication and transcription.

  8. Quantitative Literacy: Geosciences and Beyond

    Science.gov (United States)

    Richardson, R. M.; McCallum, W. G.

    2002-12-01

    Quantitative literacy seems like such a natural for the geosciences, right? The field has gone from its origin as a largely descriptive discipline to one where it is hard to imagine failing to bring a full range of mathematical tools to the solution of geological problems. Although there are many definitions of quantitative literacy, we have proposed one that is analogous to the UNESCO definition of conventional literacy: "A quantitatively literate person is one who, with understanding, can both read and represent quantitative information arising in his or her everyday life." Central to this definition is the concept that a curriculum for quantitative literacy must go beyond the basic ability to "read and write" mathematics and develop conceptual understanding. It is also critical that a curriculum for quantitative literacy be engaged with a context, be it everyday life, humanities, geoscience or other sciences, business, engineering, or technology. Thus, our definition works both within and outside the sciences. What role do geoscience faculty have in helping students become quantitatively literate? Is it our role, or that of the mathematicians? How does quantitative literacy vary between different scientific and engineering fields? Or between science and nonscience fields? We will argue that successful quantitative literacy curricula must be an across-the-curriculum responsibility. We will share examples of how quantitative literacy can be developed within a geoscience curriculum, beginning with introductory classes for nonmajors (using the Mauna Loa CO2 data set) through graduate courses in inverse theory (using singular value decomposition). We will highlight six approaches to across-the curriculum efforts from national models: collaboration between mathematics and other faculty; gateway testing; intensive instructional support; workshops for nonmathematics faculty; quantitative reasoning requirement; and individual initiative by nonmathematics faculty.

  9. Deterministic quantitative risk assessment development

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, Jane; Colquhoun, Iain [PII Pipeline Solutions Business of GE Oil and Gas, Cramlington Northumberland (United Kingdom)

    2009-07-01

    Current risk assessment practice in pipeline integrity management is to use a semi-quantitative index-based or model based methodology. This approach has been found to be very flexible and provide useful results for identifying high risk areas and for prioritizing physical integrity assessments. However, as pipeline operators progressively adopt an operating strategy of continual risk reduction with a view to minimizing total expenditures within safety, environmental, and reliability constraints, the need for quantitative assessments of risk levels is becoming evident. Whereas reliability based quantitative risk assessments can be and are routinely carried out on a site-specific basis, they require significant amounts of quantitative data for the results to be meaningful. This need for detailed and reliable data tends to make these methods unwieldy for system-wide risk k assessment applications. This paper describes methods for estimating risk quantitatively through the calibration of semi-quantitative estimates to failure rates for peer pipeline systems. The methods involve the analysis of the failure rate distribution, and techniques for mapping the rate to the distribution of likelihoods available from currently available semi-quantitative programs. By applying point value probabilities to the failure rates, deterministic quantitative risk assessment (QRA) provides greater rigor and objectivity than can usually be achieved through the implementation of semi-quantitative risk assessment results. The method permits a fully quantitative approach or a mixture of QRA and semi-QRA to suit the operator's data availability and quality, and analysis needs. For example, consequence analysis can be quantitative or can address qualitative ranges for consequence categories. Likewise, failure likelihoods can be output as classical probabilities or as expected failure frequencies as required. (author)

  10. Quantitative Luminescence Imaging System

    International Nuclear Information System (INIS)

    The goal of the MEASUREMENT OF CHEMILUMINESCENCE project is to develop and deliver a suite of imaging radiometric instruments for measuring spatial distributions of chemiluminescence. Envisioned deliverables include instruments working at the microscopic, macroscopic, and life-sized scales. Both laboratory and field portable instruments are envisioned. The project also includes development of phantoms as enclosures for the diazoluminomelanin (DALM) chemiluminescent chemistry. A suite of either phantoms in a variety of typical poses, or phantoms that could be adjusted to a variety of poses, is envisioned. These are to include small mammals (rats), mid-sized mammals (monkeys), and human body parts. A complete human phantom that can be posed is a long-term goal of the development. Taken together, the chemistry and instrumentation provide a means for imaging rf dosimetry based on chemiluminescence induced by the heat resulting from rf energy absorption. The first delivered instrument, the Quantitative Luminescence Imaging System (QLIS), resulted in a patent, and an R ampersand D Magazine 1991 R ampersand D 100 award, recognizing it as one of the 100 most significant technological developments of 1991. The current status of the project is that three systems have been delivered, several related studies have been conducted, two preliminary human hand phantoms have been delivered, system upgrades have been implemented, and calibrations have been maintained. Current development includes sensitivity improvements to the microscope-based system; extension of the large-scale (potentially life-sized targets) system to field portable applications; extension of the 2-D large-scale system to 3-D measurement; imminent delivery of a more refined human hand phantom and a rat phantom; rf, thermal and imaging subsystem integration; and continued calibration and upgrade support

  11. Quali/quantitative characterization of biogas produced in batch digesters supplied with six distinct substrates Caracterização quali/quantitativa do biogás produzido em biodigestores de batelada alimentados com seis substratos distintos

    Directory of Open Access Journals (Sweden)

    João A. Galbiatti

    2011-01-01

    Full Text Available The present research was carried out at the DER/FCAV, São Paulo State University - Brazil, with the purpose of analyzing the quantity and quality of biogas produced by six types of substrates. The substrates used in the anaerobic digestion were characterized as: 1- Litter of broiler (LB; 2- Grinded broiler litter (GBL; 3- Broiler litter with wood shavings (BLWS; 4- Grinded broiler litter with wood shavings (GBLWS; 5- Broiler litter with peanut hulls (BLPH; 6- Grinded broiler litter with peanut hull (GBLPH. It was concluded from the collected data that: the (GBL substrate showed a superior biogas accumulated production in relation to the other substrates, while the BLWS presented an inferior accumulated production; the grinded substrates showed higher quantities of accumulated biogas in relation to the non-grinded substrates, except for GBLPH, with 20.9 m³ inferior than BLPH; the period of maximum biogas production started from 45 to 60 days, declining after 120 days; at 57 days after filling up the digesters the biogas produced had levels of CH4 superior than 53%, and from 99 days all of them produced biogas with levels of CH4 superior than 70%; LB and GBL presented higher concentrations of CH4 in the biogas.Com a finalidade de se analisar quali/quantitativamente o biogás produzido por 6 tipos de substratos, efetuou-se a presente pesquisa no DER/FCAV/UNESP- SP, Brasil. Os substratos utilizados na digestão anaeróbia foram caracterizados como: 1- Esterco de aves de postura (EAP; 2- Esterco de aves de postura triturado (EAPT; 3- Esterco de aves de corte com cama de maravalha (EACM; 4- Esterco de aves de corte com cama de maravalha triturado (EACMT; 5- Esterco de aves de corte com cama de casca de amendoim (EACA, e 6- Esterco de aves de corte com cama de casca de amendoim triturado (EACAT. Dos resultados obtidos, concluiu-se que, em relação à produção acumulada de biogás, o substrato EAPT foi superior aos demais, enquanto EACM apresentou

  12. Quantitative Nuclear Medicine. Chapter 17

    International Nuclear Information System (INIS)

    Planar imaging is still used in clinical practice although tomographic imaging (single photon emission computed tomography (SPECT) and positron emission tomography (PET)) is becoming more established. In this chapter, quantitative methods for both imaging techniques are presented. Planar imaging is limited to single photon. For both SPECT and PET, the focus is on the quantitative methods that can be applied to reconstructed images

  13. Mastering R for quantitative finance

    CERN Document Server

    Berlinger, Edina; Badics, Milán; Banai, Ádám; Daróczi, Gergely; Dömötör, Barbara; Gabler, Gergely; Havran, Dániel; Juhász, Péter; Margitai, István; Márkus, Balázs; Medvegyev, Péter; Molnár, Julia; Szucs, Balázs Árpád; Tuza, Ágnes; Vadász, Tamás; Váradi, Kata; Vidovics-Dancs, Ágnes

    2015-01-01

    This book is intended for those who want to learn how to use R's capabilities to build models in quantitative finance at a more advanced level. If you wish to perfectly take up the rhythm of the chapters, you need to be at an intermediate level in quantitative finance and you also need to have a reasonable knowledge of R.

  14. Rational quantitative safety goals: a summary

    International Nuclear Information System (INIS)

    We introduce the notion of a Rational Quantitative Safety Goal. Such a goal reflects the imprecision and vagueness inherent in any reasonable notion of adequate safety and permits such vagueness to be incorporated into the formal regulatory decision-making process. A quantitative goal of the form, the parameter x, characterizing the safety level of the nuclear plant, shall not exceed the value x0, for example, is of a non-rational nature in that it invokes a strict binary logic in which the parameter space underlying x is cut sharply into two portions: that containing those values of x that comply with the goal and that containing those that do not. Here, we utilize an alternative form of logic which, in accordance with any intuitively reasonable notion of safety, permits a smooth transition of a safety determining parameter between the adequately safe and inadequately safe domains. Fuzzy set theory provides a suitable mathematical basis for the formulation of rational quantitative safety goals. The decision-making process proposed here is compatible with current risk assessment techniques and produces results in a transparent and useful format. Our methodology is illustrated with reference to the NUS Corporation risk assessment of the Limerick Generating Station

  15. Quantitative Proteomic Analysis of the Human Nucleolus.

    Science.gov (United States)

    Bensaddek, Dalila; Nicolas, Armel; Lamond, Angus I

    2016-01-01

    Recent years have witnessed spectacular progress in the field of mass spectrometry (MS)-based quantitative proteomics, including advances in instrumentation, chromatography, sample preparation methods, and experimental design for multidimensional analyses. It is now possible not only to identify most of the protein components of a cell proteome in a single experiment, but also to describe additional proteome dimensions, such as protein turnover rates, posttranslational modifications, and subcellular localization. Furthermore, by comparing the proteome at different time points, it is possible to create a "time-lapse" view of proteome dynamics. By combining high-throughput quantitative proteomics with detailed subcellular fractionation protocols and data analysis techniques it is also now possible to characterize in detail the proteomes of specific subcellular organelles, providing important insights into cell regulatory mechanisms and physiological responses. In this chapter we present a reliable workflow and protocol for MS-based analysis and quantitation of the proteome of nucleoli isolated from human cells. The protocol presented is based on a SILAC analysis of human MCF10A-Src-ER cells with analysis performed on a Q-Exactive Plus Orbitrap MS instrument (Thermo Fisher Scientific). The subsequent chapter describes how to process the resulting raw MS files from this experiment using MaxQuant software and data analysis procedures to evaluate the nucleolar proteome using customized R scripts. PMID:27576725

  16. Some exercises in quantitative NMR imaging

    International Nuclear Information System (INIS)

    The articles represented in this thesis result from a series of investigations that evaluate the potential of NMR imaging as a quantitative research tool. In the first article the possible use of proton spin-lattice relaxation time T1 in tissue characterization, tumor recognition and monitoring tissue response to radiotherapy is explored. The next article addresses the question whether water proton spin-lattice relaxation curves of biological tissues are adequately described by a single time constant T1, and analyzes the implications of multi-exponentiality for quantitative NMR imaging. In the third article the use of NMR imaging as a quantitative research tool is discussed on the basis of phantom experiments. The fourth article describes a method which enables unambiguous retrieval of sign information in a set of magnetic resonance images of the inversion recovery type. The next article shows how this method can be adapted to allow accurate calculation of T1 pictures on a pixel-by-pixel basis. The sixth article, finally, describes a simulation procedure which enables a straightforward determination of NMR imaging pulse sequence parameters for optimal tissue contrast. (orig.)

  17. Quantitatively Characterizing the Tight-bond Cluster in Zr55 Cu35 Al10 Metallic Glass%Zr55 Cu35 Al 10金属玻璃中紧键结合团簇的定量表征∗

    Institute of Scientific and Technical Information of China (English)

    陈刚; 杨现; 范沧; 唐政

    2015-01-01

    定量表征金属玻璃的原子结构是深入理解和解释金属玻璃独特的物理性能和力学性能的关键。本文通过铜模吸铸法制备了 Zr55 Cu35 Al10大块金属玻璃圆棒状试样,并利用中子衍射获得试样的对分布函数,从而定量地定义了金属玻璃紧键合团簇模型中的紧键合团簇。还通过第一性原理分子动力学模拟对 Zr55 Cu35 Al10大块金属玻璃局域原子结构进行模拟计算,从模拟得到的结构中提取了许多紧键合团簇,并通过团簇尺寸对其定量地表征。%The quantitative characterization of the atomic structure of bulk metallic glass plays an im-portant role in deeply understanding its individual physical properties and mechanical properties.Some cy-lindrical Zr5 5 Cu3 5 Al1 0 bulk metallic glass specimens were prepared with a suction casting in a copper mold, the pair distribution function (PDF)was obtained by neutron diffraction,and then,the tight bond cluster was defined in the present work.In addition,the local atomic structure of Zr5 5 Cu3 5 Al1 0 bulk metallic glass was simulated by ab initio molecular dynamic (AIMD).A large number of tight-bond clusters were extrac-ted from the results and simulated in association with the quantitative characterization of sizes,which were abundant in the ideal tight-bond cluster model at present.

  18. Validation of reference genes for quantitative RT-qPCR studies of gene expression in Atlantic cod (Gadus morhua l. during temperature stress

    Directory of Open Access Journals (Sweden)

    Karlsen Hans E

    2011-04-01

    Full Text Available Abstract Background One important physiological response to environmental stress in animals is change in gene expression. To obtain reliable data from gene expression studies using RT-qPCR it is important to evaluate a set of possible reference genes as normalizers for expression. The expression of these candidate genes should be analyzed in the relevant tissues during normal and stressed situations. To find suitable reference genes it was crucial that the genes were stably expressed also during a situation of physiological stress. For poikilotermic animals like cod, changes in temperature are normal, but if the changes are faster than physiological compensation, the animals respond with typical stress responses. It has previously been shown that Atlantic cod show stress responses when elevation of water temperature is faster than 1 degree/day, for this reason we chose hyperthermia as stress agent for this experiment. Findings We here describe the expression of eight candidate reference genes from Atlantic cod (Gadus morhua l. and their stability during thermal stress (temperature elevation of one degree C/day for 5 days. The genes investigated were: Eukaryotic elongation factor 1 alpha, ef1a; 18s ribosomal RNA; 18s, Ubiquitin conjugate protein; ubiq, cytoskeletal beta-actin; actb, major histcompatibility complex I; MHC-I light chain, beta-2 -microglobulin; b2m, cytoskeletal alpha-tubulin; tba1c, acidic ribosomal phosphoprotein; rplp1, glucose-6-phosphate dehydrogenase; g6pd. Their expression were analyzed in 6 tissues (liver, head kidney, intestine, spleen, heart and gills from cods exposed to elevated temperature and compared to a control group. Although there were variations between tissues with respect to reference gene stability, four transcripts were more consistent than the others: ubiq, ef1a, 18s and rplp1. We therefore used these to analyze the expression of stress related genes (heat shock proteins induced during hyperthermia. We found

  19. Spectroscopic Tools for Quantitative Studies of DNA Structure and Dynamics

    DEFF Research Database (Denmark)

    Preus, Søren

    The main objective of this thesis is to develop quantitative fluorescence-based, spectroscopic tools for probing the 3D structure and dynamics of DNA and RNA. The thesis is founded on six peer-reviewed papers covering mainly the development, characterization and use of fluorescent nucleobase...

  20. Etiology and Diagnosis of Major Depression - A Novel Quantitative Approach

    DEFF Research Database (Denmark)

    Ottesen, Johnny T.

    2013-01-01

    Background: Classical psychiatric opinions are relative uncertain and treatment results are not impressive when dealing with major depression. Depression is related to the endocrine system, but despite much effort a good quantitative measure for characterizing depression has not yet emerged. Meth...

  1. Quantitative magnetic resonance imaging of cortical multiple sclerosis pathology

    DEFF Research Database (Denmark)

    Tardif, Christine L; Bedell, Barry J; Eskildsen, Simon Fristed;

    2012-01-01

    pathology. The objective of this study was to characterize the MRI signature of CLs to help interpret the changes seen in vivo and elucidate the factors limiting their visualization. A quantitative 3D high-resolution (350 μm isotropic) MRI study at 3 Tesla of a fixed post mortem cerebral hemisphere from...

  2. Quantitative EPR A Practitioners Guide

    CERN Document Server

    Eaton, Gareth R; Barr, David P; Weber, Ralph T

    2010-01-01

    This is the first comprehensive yet practical guide for people who perform quantitative EPR measurements. No existing book provides this level of practical guidance to ensure the successful use of EPR. There is a growing need in both industrial and academic research to provide meaningful and accurate quantitative EPR results. This text discusses the various sample, instrument and software related aspects required for EPR quantitation. Specific topics include: choosing a reference standard, resonator considerations (Q, B1, Bm), power saturation characteristics, sample positioning, and finally, putting all the factors together to obtain an accurate spin concentration of a sample.

  3. Quantitative vs qualitative research methods.

    Science.gov (United States)

    Lakshman, M; Sinha, L; Biswas, M; Charles, M; Arora, N K

    2000-05-01

    Quantitative methods have been widely used because of the fact that things that can be measured or counted gain scientific credibility over the unmeasurable. But the extent of biological abnormality, severity, consequences and the impact of illness cannot be satisfactorily captured and answered by the quantitative research alone. In such situations qualitative methods take a holistic perspective preserving the complexities of human behavior by addressing the "why" and "how" questions. In this paper an attempt has been made to highlight the strengths and weaknesses of both the methods and also that a balanced mix of both qualitative as well as quantitative methods yield the most valid and reliable results.

  4. A Quantitative Characterization of Weighted Kripke Structures in Temporal Logic

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand; Thrane, Claus Rørbæk; Fahrenberg, Uli

    2009-01-01

    We extend the usual notion of Kripke Structures with a weighted transition relation, and generalize the usual Boolean satisfaction relation of CTL to a map which assigns to states and temporal formulae a real-valued distance describing the degree of satisfaction. We describe a general approach...

  5. Characterizing the Anaerobic Response of Chlamydomonas reinhardtii by Quantitative Proteomics

    OpenAIRE

    Terashima, Mia; Specht, Michael; Naumann, Bianca; Hippler, Michael

    2010-01-01

    The versatile metabolism of the green alga Chlamydomonas reinhardtii is reflected in its complex response to anaerobic conditions. The anaerobic response is also remarkable in the context of renewable energy because C. reinhardtii is able to produce hydrogen under anaerobic conditions. To identify proteins involved during anaerobic acclimation as well as to localize proteins and pathways to the powerhouses of the cell, chloroplasts and mitochondria from C. reinhardtii in aerobic and anaerobic...

  6. Quantitative spatiotemporal characterization of methane venting from lake sediments

    Science.gov (United States)

    Scandella, B.; Pillsbury, L.; Weber, T.; Ruppel, C. D.; Hemond, H.; Juanes, R.

    2014-12-01

    Methane is a potent greenhouse gas, and the production and emission of methane from sediments in inland waters and shallow oceans both contributes to and may be exacerbated by climate change. In some of these shallow-water settings, methane fluxes are often controlled by episodic free-gas venting. The fraction of the methane released from the sediments that bypasses dissolution in the water column and reaches the atmosphere impacts the magnitude of the climate forcing, and this fraction depends critically on the mode and spatiotemporal characteristics of the bubble releases. The spacing and persistence of the gas vents may be determined by the heterogeneity of the methane source, but within regions of uniform methanogenesis they arise from the competition between mechanisms driving lateral and vertical transport of methane in the sediments. Here, we present measurements of the spacing, persistence and variability in intensity of methane vents within a wide area of lake sediments (~400 m2) and over a multi-month period. The measurements were made using a fixed-location Imagenex DeltaT 837B multibeam sonar, which was calibrated to quantify gas fluxes with unprecedented spatial and temporal resolution (~0.5 m, 6 Hz). Drops in hydrostatic pressure were a characteristic trigger for the sonar-detected ebullition events, and the episodicity of the fluxes is reproduced with a mechanistic numerical model of methane venting through dynamic conduits that dilate in response to hydrostatic unloading. The spatial characteristics of the sonar-detected vents inform conceptual and mathematical models of methane transport and release from deformable sediments, as well as the uncertainty associated with upscaling. Taken together, these results point towards a better understanding of the microscale processes controlling methane venting from deformable sediments, as well as their impact on large-scale methane fluxes from shallow-water bodies. Figure: Top: time series of daily sonar-estimated gas fluxes over the entire observation area (black bars and circles) from March 1 - May 18, 2014, compared with a mechanistic, numerical model (orange) that is driven by fluctuations in hydrostatic pressure (blue, rescaled to fit). Bottom: maps of fluxes at 0.5 m resolution within the sonar fan, for March 13 and 14.

  7. Characterization of persistent postoperative pain by quantitative sensory testing

    DEFF Research Database (Denmark)

    Werner, Mads U.; Kehlet, Henrik

    2010-01-01

    of the sensory system either by mechanical, thermal or electrical stimuli, with assessment of the evoked psychophysical response. QST has been used in prospective assessments of how and why some individuals develop persistent postoperative pain. This comprehensive review describes, first, QST as a predictive...

  8. Quantitative characterization of the viscosity of a microemulsion

    Science.gov (United States)

    Berg, Robert F.; Moldover, Michael R.; Huang, John S.

    1987-01-01

    The viscosity of the three-component microemulsion water/decane/AOT has been measured as a function of temperature and droplet volume fraction. At temperatures well below the phase-separation temperature the viscosity is described by treating the droplets as hard spheres suspended in decane. Upon approaching the two-phase region from low temperature, there is a large (as much as a factor of four) smooth increase of the viscosity which may be related to the percolation-like transition observed in the electrical conductivity. This increase in viscosity is not completely consistent with either a naive electroviscous model or a simple clustering model. The divergence of the viscosity near the critical point (39 C) is superimposed upon the smooth increase. The magnitude and temperature dependence of the critical divergence are similar to that seen near the critical points of binary liquid mixtures.

  9. Characterization of persistent postoperative pain by quantitative sensory testing

    DEFF Research Database (Denmark)

    Werner, Mads U.; Kehlet, Henrik

    2010-01-01

    , the implications of these findings for use of QST in future research are discussed. More rational design of predictive studies in PPP, based on surgical procedure specific approaches, is needed in order to improve our understanding of prevention and management of this debilitating postsurgical condition....

  10. Quantitative Application Data Flow Characterization for Heterogeneous Multicore Architectures

    NARCIS (Netherlands)

    Ostadzadeh, S.A.

    2012-01-01

    Recent trends show a steady increase in the utilization of heterogeneous multicore architectures in order to address the ever-growing need for computing performance. These emerging architectures pose specific challenges with regard to their programmability. In addition, they require efficient applic

  11. Quantitative methods in accounting research

    OpenAIRE

    Marek Gruszczynski

    2009-01-01

    Quantitative methods are in frequent use in modern accounting research. The evidence may be found e.g. in the journals like “Journal of Accounting Research”, “European Accounting Review”, “Review of Quantitative Finance and Accounting” or in the Accounting Research Network in SSRN base. Paper presents a brief survey of research areas and statistical-econometric approaches in accounting research. Particular reference goes to research on corporate disclosure. Methodological component of the pap...

  12. Quantitative determination of the structure-property relationships in nuclear fuel element materials. Final report, June 1969--July 1973

    International Nuclear Information System (INIS)

    New developments in quantitative microscopy are first described. The use of the described techniques to quantitatively characterize the microstructural states of nickel and uranium dioxide samples is then discussed. The determination of gas permeability, thermal conductivity, mechanical properties, and creep behavior in the characterized samples are also described. (U.S.)

  13. Quantitative NDE of Composite Structures at NASA

    Science.gov (United States)

    Cramer, K. Elliott; Leckey, Cara A. C.; Howell, Patricia A.; Johnston, Patrick H.; Burke, Eric R.; Zalameda, Joseph N.; Winfree, William P.; Seebo, Jeffery P.

    2015-01-01

    The use of composite materials continues to increase in the aerospace community due to the potential benefits of reduced weight, increased strength, and manufacturability. Ongoing work at NASA involves the use of the large-scale composite structures for spacecraft (payload shrouds, cryotanks, crew modules, etc). NASA is also working to enable the use and certification of composites in aircraft structures through the Advanced Composites Project (ACP). The rapid, in situ characterization of a wide range of the composite materials and structures has become a critical concern for the industry. In many applications it is necessary to monitor changes in these materials over a long time. The quantitative characterization of composite defects such as fiber waviness, reduced bond strength, delamination damage, and microcracking are of particular interest. The research approaches of NASA's Nondestructive Evaluation Sciences Branch include investigation of conventional, guided wave, and phase sensitive ultrasonic methods, infrared thermography and x-ray computed tomography techniques. The use of simulation tools for optimizing and developing these methods is also an active area of research. This paper will focus on current research activities related to large area NDE for rapidly characterizing aerospace composites.

  14. Quantitative linkage genome scan for atopy in a large collection of Caucasian families

    DEFF Research Database (Denmark)

    Webb, BT; van den Oord, E; Akkari, A;

    2007-01-01

    Quantitative phenotypes correlated with a complex disorder offer increased power to detect linkage in comparison to affected-unaffected classifications. Asthma is a complex disorder characterized by periods of bronchial obstruction and increased bronchial hyper reactivity. In childhood and early ...

  15. Ocular manifestations of Apert and Crouzon syndromes: qualitative and quantitative findings

    DEFF Research Database (Denmark)

    Kreiborg, Sven; Cohen, M Michael

    2010-01-01

    There are significant differences in the ocular manifestations of Apert and Crouzon syndromes. Here, we present qualitative and quantitative data about the oculo-orbital region to demonstrate these differences. Although ocular protosis and hypertelorism characterize both disorders, the nature...

  16. Quantitative mass spectrometry: an overview

    Science.gov (United States)

    Urban, Pawel L.

    2016-10-01

    Mass spectrometry (MS) is a mainstream chemical analysis technique in the twenty-first century. It has contributed to numerous discoveries in chemistry, physics and biochemistry. Hundreds of research laboratories scattered all over the world use MS every day to investigate fundamental phenomena on the molecular level. MS is also widely used by industry-especially in drug discovery, quality control and food safety protocols. In some cases, mass spectrometers are indispensable and irreplaceable by any other metrological tools. The uniqueness of MS is due to the fact that it enables direct identification of molecules based on the mass-to-charge ratios as well as fragmentation patterns. Thus, for several decades now, MS has been used in qualitative chemical analysis. To address the pressing need for quantitative molecular measurements, a number of laboratories focused on technological and methodological improvements that could render MS a fully quantitative metrological platform. In this theme issue, the experts working for some of those laboratories share their knowledge and enthusiasm about quantitative MS. I hope this theme issue will benefit readers, and foster fundamental and applied research based on quantitative MS measurements. This article is part of the themed issue 'Quantitative mass spectrometry'.

  17. Quantitative mass spectrometry: an overview

    Science.gov (United States)

    2016-01-01

    Mass spectrometry (MS) is a mainstream chemical analysis technique in the twenty-first century. It has contributed to numerous discoveries in chemistry, physics and biochemistry. Hundreds of research laboratories scattered all over the world use MS every day to investigate fundamental phenomena on the molecular level. MS is also widely used by industry—especially in drug discovery, quality control and food safety protocols. In some cases, mass spectrometers are indispensable and irreplaceable by any other metrological tools. The uniqueness of MS is due to the fact that it enables direct identification of molecules based on the mass-to-charge ratios as well as fragmentation patterns. Thus, for several decades now, MS has been used in qualitative chemical analysis. To address the pressing need for quantitative molecular measurements, a number of laboratories focused on technological and methodological improvements that could render MS a fully quantitative metrological platform. In this theme issue, the experts working for some of those laboratories share their knowledge and enthusiasm about quantitative MS. I hope this theme issue will benefit readers, and foster fundamental and applied research based on quantitative MS measurements. This article is part of the themed issue ‘Quantitative mass spectrometry’. PMID:27644965

  18. Quantitative mass spectrometry: an overview.

    Science.gov (United States)

    Urban, Pawel L

    2016-10-28

    Mass spectrometry (MS) is a mainstream chemical analysis technique in the twenty-first century. It has contributed to numerous discoveries in chemistry, physics and biochemistry. Hundreds of research laboratories scattered all over the world use MS every day to investigate fundamental phenomena on the molecular level. MS is also widely used by industry-especially in drug discovery, quality control and food safety protocols. In some cases, mass spectrometers are indispensable and irreplaceable by any other metrological tools. The uniqueness of MS is due to the fact that it enables direct identification of molecules based on the mass-to-charge ratios as well as fragmentation patterns. Thus, for several decades now, MS has been used in qualitative chemical analysis. To address the pressing need for quantitative molecular measurements, a number of laboratories focused on technological and methodological improvements that could render MS a fully quantitative metrological platform. In this theme issue, the experts working for some of those laboratories share their knowledge and enthusiasm about quantitative MS. I hope this theme issue will benefit readers, and foster fundamental and applied research based on quantitative MS measurements.This article is part of the themed issue 'Quantitative mass spectrometry'.

  19. Quantitative mass spectrometry: an overview.

    Science.gov (United States)

    Urban, Pawel L

    2016-10-28

    Mass spectrometry (MS) is a mainstream chemical analysis technique in the twenty-first century. It has contributed to numerous discoveries in chemistry, physics and biochemistry. Hundreds of research laboratories scattered all over the world use MS every day to investigate fundamental phenomena on the molecular level. MS is also widely used by industry-especially in drug discovery, quality control and food safety protocols. In some cases, mass spectrometers are indispensable and irreplaceable by any other metrological tools. The uniqueness of MS is due to the fact that it enables direct identification of molecules based on the mass-to-charge ratios as well as fragmentation patterns. Thus, for several decades now, MS has been used in qualitative chemical analysis. To address the pressing need for quantitative molecular measurements, a number of laboratories focused on technological and methodological improvements that could render MS a fully quantitative metrological platform. In this theme issue, the experts working for some of those laboratories share their knowledge and enthusiasm about quantitative MS. I hope this theme issue will benefit readers, and foster fundamental and applied research based on quantitative MS measurements.This article is part of the themed issue 'Quantitative mass spectrometry'. PMID:27644965

  20. Classification of cassava genotypes based on qualitative and quantitative data.

    Science.gov (United States)

    Oliveira, E J; Oliveira Filho, O S; Santos, V S

    2015-02-02

    We evaluated the genetic variation of cassava accessions based on qualitative (binomial and multicategorical) and quantitative traits (continuous). We characterized 95 accessions obtained from the Cassava Germplasm Bank of Embrapa Mandioca e Fruticultura; we evaluated these accessions for 13 continuous, 10 binary, and 25 multicategorical traits. First, we analyzed the accessions based only on quantitative traits; next, we conducted joint analysis (qualitative and quantitative traits) based on the Ward-MLM method, which performs clustering in two stages. According to the pseudo-F, pseudo-t2, and maximum likelihood criteria, we identified five and four groups based on quantitative trait and joint analysis, respectively. The smaller number of groups identified based on joint analysis may be related to the nature of the data. On the other hand, quantitative data are more subject to environmental effects in the phenotype expression; this results in the absence of genetic differences, thereby contributing to greater differentiation among accessions. For most of the accessions, the maximum probability of classification was >0.90, independent of the trait analyzed, indicating a good fit of the clustering method. Differences in clustering according to the type of data implied that analysis of quantitative and qualitative traits in cassava germplasm might explore different genomic regions. On the other hand, when joint analysis was used, the means and ranges of genetic distances were high, indicating that the Ward-MLM method is very useful for clustering genotypes when there are several phenotypic traits, such as in the case of genetic resources and breeding programs.

  1. Quantitative Proteome Mapping of Nitrotyrosines

    Energy Technology Data Exchange (ETDEWEB)

    Bigelow, Diana J.; Qian, Weijun

    2008-02-10

    An essential first step in the understanding disease and environmental perturbations is the early and quantitative detection of the increased levels of the inflammatory marker nitrotyrosine, as compared with its endogenous levels within the tissue or cellular proteome. Thus, methods that successfully address a proteome-wide quantitation of nitrotyrosine and related oxidative modifications can provide early biomarkers of risk and progression of disease as well as effective strategies for therapy. Multidimensional separations LC coupled with tandem mass spectrometry (LC-MS/MS) has, in recent years, significantly expanded our knowledge of human (and mammalian model system) proteomes including some nascent work in identification of post-translational modifications. In the following review, we discuss the application of LC-MS/MS for quantitation and identification of nitrotyrosine-modified proteins within the context of complex protein mixtures presented in mammalian proteomes.

  2. Quantitative relations between corruption and economic factors

    CERN Document Server

    Shao, Jia; Podobnik, Boris; Stanley, H Eugene

    2007-01-01

    We report quantitative relations between corruption level and economic factors, such as country wealth and foreign investment per capita, which are characterized by a power law spanning multiple scales of wealth and investments per capita. These relations hold for diverse countries, and also remain stable over different time periods. We also observe a negative correlation between level of corruption and long-term economic growth. We find similar results for two independent indices of corruption, suggesting that the relation between corruption and wealth does not depend on the specific measure of corruption. The functional relations we report have implications when assessing the relative level of corruption for two countries with comparable wealth, and for quantifying the impact of corruption on economic growth and foreign investments.

  3. Quantitative current measurements using scanning magnetoresistance microscopy.

    Science.gov (United States)

    Takezaki, Taiichi; Sueoka, Kazuhisa

    2008-08-01

    We have demonstrated the capability of scanning magnetoresistance microscope (SMRM) to be used for quantitative current measurements. The SMRM is a magnetic microscope that is based on an atomic force microscope (AFM) and simultaneously measures the localized surface magnetic field distribution and surface topography. The proposed SMRM employs an in-house built AFM cantilever equipped with a miniaturized magnetoresistive (MR) sensor as a magnetic field sensor. In this study, a spin-valve type MR sensor with a width of 1 microm was used to measure the magnetic field distribution induced by a current carrying wire with a width of 5 microm and a spacing of 1.6 microm at room temperature and under ambient conditions. Simultaneous imaging of the magnetic field distribution and the topography was successfully performed in the DC current ranging from 500 microA to 8 mA. The characterized SV sensor, which has a linear response to magnetic fields, offers the quantitative analysis of a magnetic field and current. The measured magnetic field strength was in good agreement with the result simulated using Biot-Savart's law. PMID:18599218

  4. Quantitative two-qutrit entanglement

    Energy Technology Data Exchange (ETDEWEB)

    Eltschka, Christopher [Institut fuer Theoretische Physik, Universitaet Regensburg, D-93040 Regensburg (Germany); Siewert, Jens [Departamento de Quimica Fisica, Universidad del Pais Vasco UPV/EHU, 48080 Bilbao (Spain); IKERBASQUE, Basque Foundation for Science, 48011 Bilbao (Spain)

    2013-07-01

    We introduce the new concept of axisymmetric bipartite states. For d x d-dimensional systems these states form a two-parameter family of nontrivial mixed states that include the isotropic states. We present exact quantitative results for class-specific entanglement as well as for the negativity and I-concurrence of two-qutrit axisymmetric states. These results have interesting applications such as for quantitative witnesses of class-specific entanglement in arbitrary two-qutrit states and as device-independent witness for the number of entangled dimensions.

  5. Quantitative risk assessment of CO

    NARCIS (Netherlands)

    Koornneef, J.; Spruijt, M.; Molag, M.; Ramírez, A.; Turkenburg, W.; Faaij, A.

    2010-01-01

    A systematic assessment, based on an extensive literature review, of the impact of gaps and uncertainties on the results of quantitative risk assessments (QRAs) for CO2 pipelines is presented. Sources of uncertainties that have been assessed are: failure rates, pipeline pressure, temperat

  6. La quantite en islandais modern

    Directory of Open Access Journals (Sweden)

    Magnús Pétursson

    1978-12-01

    Full Text Available La réalisation phonétique de la quantité en syllabe accentuée dans la lecture de deux textes continus. Le problème de la quantité est un des problèmes les plus étudiés dans la phonologie de l'islandais moderne. Du point de vue phonologique il semble qu'on ne peut pas espérer apporter du nouveau, les possibilités théoriques ayant été pratiquement épuisées comme nous 1'avons rappelé dans notre étude récente (Pétursson 1978, pp. 76-78. Le résultat le plus inattendu des recherches des dernières années est sans doute la découverte d'une différenciation quantitative entre le Nord et le Sud de l'Islande (Pétursson 1976a. Il est pourtant encore prématuré de parler de véritables zones quantitatives puisqu'on n' en connaît ni les limites ni l' étendue sur le plan géographique.

  7. Time-resolved quantitative phosphoproteomics

    DEFF Research Database (Denmark)

    Verano-Braga, Thiago; Schwämmle, Veit; Sylvester, Marc;

    2012-01-01

    proteins involved in the Ang-(1-7) signaling, we performed a mass spectrometry-based time-resolved quantitative phosphoproteome study of human aortic endothelial cells (HAEC) treated with Ang-(1-7). We identified 1288 unique phosphosites on 699 different proteins with 99% certainty of correct peptide...

  8. [Qualitative and quantitative EEG-findings in schizophrenia (author's transl)].

    Science.gov (United States)

    Itil, T M

    1978-03-01

    The results of the qualitative but particularly the quantitative EEG-studies indicate that 1. The EEG of adult schizophrenics is characterized by an appearance of excessive fast activity along with some slow waves and the lack of alpha-activity. 2. Excessive fast activity and lack of alpha-waves have also been found in the EEGs of psychotic children and most interestingly in children whose parents (particularly the mother) are schizophrenic (high risk children). 3. Based on the studies during sleep and investigations with neuroleptics, it was established that the origin of the excess fast activity in schizophrenia cannot be the muscle potential. Particularly the excess fast activity in high risk children for schizophrenia goes against the muscle potential hypothesis. 4. The quantitative EEG changes seen in schizophrenia show similarity to those seen after hallucinogenic compounds particularly after anticholinergic hallucinogenics. 5. All neuroleptics (major tranquilizers) produce quantitative EEG alterations which are almost diametrically opposite to those seen in schizoprenia. PMID:416942

  9. Mapping Protein-Protein Interactions by Quantitative Proteomics

    DEFF Research Database (Denmark)

    Dengjel, Joern; Kratchmarova, Irina; Blagoev, Blagoy

    2010-01-01

    Proteins exert their function inside a cell generally in multiprotein complexes. These complexes are highly dynamic structures changing their composition over time and cell state. The same protein may thereby fulfill different functions depending on its binding partners. Quantitative mass...... spectrometry (MS)-based proteomics in combination with affinity purification protocols has become the method of choice to map and track the dynamic changes in protein-protein interactions, including the ones occurring during cellular signaling events. Different quantitative MS strategies have been used to...... characterize protein interaction networks. In this chapter we describe in detail the use of stable isotope labeling by amino acids in cell culture (SILAC) for the quantitative analysis of stimulus-dependent dynamic protein interactions....

  10. [Qualitative and quantitative EEG-findings in schizophrenia (author's transl)].

    Science.gov (United States)

    Itil, T M

    1978-03-01

    The results of the qualitative but particularly the quantitative EEG-studies indicate that 1. The EEG of adult schizophrenics is characterized by an appearance of excessive fast activity along with some slow waves and the lack of alpha-activity. 2. Excessive fast activity and lack of alpha-waves have also been found in the EEGs of psychotic children and most interestingly in children whose parents (particularly the mother) are schizophrenic (high risk children). 3. Based on the studies during sleep and investigations with neuroleptics, it was established that the origin of the excess fast activity in schizophrenia cannot be the muscle potential. Particularly the excess fast activity in high risk children for schizophrenia goes against the muscle potential hypothesis. 4. The quantitative EEG changes seen in schizophrenia show similarity to those seen after hallucinogenic compounds particularly after anticholinergic hallucinogenics. 5. All neuroleptics (major tranquilizers) produce quantitative EEG alterations which are almost diametrically opposite to those seen in schizoprenia.

  11. Quantitative proteome profiling of normal human circulating microparticles

    DEFF Research Database (Denmark)

    Østergaard, Ole; Nielsen, Christoffer T; Iversen, Line V;

    2012-01-01

    Circulating microparticles (MPs) are produced as part of normal physiology. Their numbers, origin, and composition change in pathology. Despite this, the normal MP proteome has not yet been characterized with standardized high-resolution methods. We here quantitatively profile the normal MP...... proteome using nano-LC-MS/MS on an LTQ-Orbitrap with optimized sample collection, preparation, and analysis of 12 different normal samples. Analytical and procedural variation were estimated in triply processed samples analyzed in triplicate from two different donors. Label-free quantitation was validated...... by the correlation of cytoskeletal protein intensities with MP numbers obtained by flow cytometry. Finally, the validity of using pooled samples was evaluated using overlap protein identification numbers and multivariate data analysis. Using conservative parameters, 536 different unique proteins were quantitated...

  12. Quantitative biological imaging by ptychographic X-ray diffraction microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Giewekemeyer, Klaus; Kalbfleisch, Sebastian; Beerlink, Andre; Salditt, Tim [Institut fuer Roentgenphysik, Georg-August-Universitaet Goettingen (Germany); Thibault, Pierre; Dierolf, Martin; Pfeiffer, Franz [Department Physik (E17), Technische Universitaet Muenchen, Garching (Germany); Kewish, Cameron M. [Paul Scherrer Institut, Villigen PSI (Switzerland)

    2010-07-01

    Mesoscopic structures with specific functions are abundant in many cellular systems and have been well characterized by electron microscopy in the past. However, the quantitative study of the three-dimensional structure and density of subcellular components remains a difficult problem. In this contribution we show how these limitations could be overcome in the future by the application of recently introduced and now rapidly evolving coherent X-ray imaging techniques for quantitative biological imaging on the nanoscale. More specifically, we report on a recent scanning (ptychographic) diffraction experiment on unstained and unsliced freeze-dried cells of the bacterium Deinococcus radiourans using only a pinhole as beam defining optical element. As a result quantitative density projections well below optical resolution have been achieved.

  13. Quantitative multimodality imaging in cancer research and therapy.

    Science.gov (United States)

    Yankeelov, Thomas E; Abramson, Richard G; Quarles, C Chad

    2014-11-01

    Advances in hardware and software have enabled the realization of clinically feasible, quantitative multimodality imaging of tissue pathophysiology. Earlier efforts relating to multimodality imaging of cancer have focused on the integration of anatomical and functional characteristics, such as PET-CT and single-photon emission CT (SPECT-CT), whereas more-recent advances and applications have involved the integration of multiple quantitative, functional measurements (for example, multiple PET tracers, varied MRI contrast mechanisms, and PET-MRI), thereby providing a more-comprehensive characterization of the tumour phenotype. The enormous amount of complementary quantitative data generated by such studies is beginning to offer unique insights into opportunities to optimize care for individual patients. Although important technical optimization and improved biological interpretation of multimodality imaging findings are needed, this approach can already be applied informatively in clinical trials of cancer therapeutics using existing tools. These concepts are discussed herein.

  14. Automated Quantitative Rare Earth Elements Mineralogy by Scanning Electron Microscopy

    Science.gov (United States)

    Sindern, Sven; Meyer, F. Michael

    2016-09-01

    Increasing industrial demand of rare earth elements (REEs) stems from the central role they play for advanced technologies and the accelerating move away from carbon-based fuels. However, REE production is often hampered by the chemical, mineralogical as well as textural complexity of the ores with a need for better understanding of their salient properties. This is not only essential for in-depth genetic interpretations but also for a robust assessment of ore quality and economic viability. The design of energy and cost-efficient processing of REE ores depends heavily on information about REE element deportment that can be made available employing automated quantitative process mineralogy. Quantitative mineralogy assigns numeric values to compositional and textural properties of mineral matter. Scanning electron microscopy (SEM) combined with a suitable software package for acquisition of backscatter electron and X-ray signals, phase assignment and image analysis is one of the most efficient tools for quantitative mineralogy. The four different SEM-based automated quantitative mineralogy systems, i.e. FEI QEMSCAN and MLA, Tescan TIMA and Zeiss Mineralogic Mining, which are commercially available, are briefly characterized. Using examples of quantitative REE mineralogy, this chapter illustrates capabilities and limitations of automated SEM-based systems. Chemical variability of REE minerals and analytical uncertainty can reduce performance of phase assignment. This is shown for the REE phases parisite and synchysite. In another example from a monazite REE deposit, the quantitative mineralogical parameters surface roughness and mineral association derived from image analysis are applied for automated discrimination of apatite formed in a breakdown reaction of monazite and apatite formed by metamorphism prior to monazite breakdown. SEM-based automated mineralogy fulfils all requirements for characterization of complex unconventional REE ores that will become

  15. Quantitative gold nanoparticle analysis methods: A review.

    Science.gov (United States)

    Yu, Lei; Andriola, Angelo

    2010-08-15

    Research and development in the area of gold nanoparticles' (AuNPs) preparation, characterization, and applications are burgeoning in recent years. Many of the techniques and protocols are very mature, but two major concerns are with the mass domestic production and the consumption of AuNP based products. First, how many AuNPs exist in a dispersion? Second, where are the AuNPs after digestion by the environment and how many are there? To answer these two questions, reliable and reproducible methods are needed to analyze the existence and the population of AuNP in samples. This review summarized the most recent chemical and particle quantitative analysis methods that have been used to characterize the concentration (in number of moles of gold per liter) or population (in number of particles per mL) of AuNPs. The methods summarized in this review include, mass spectroscopy, electroanalytical methods, spectroscopic methods, and particle counting methods. These methods may count the number of AuNP directly or analyze the total concentration of element gold in an AuNP dispersion.

  16. Quantitative vibrational dynamics of iron in nitrosyl porphyrins

    OpenAIRE

    Leu, B. M.; Zgierski, M. Z.; Wyllie, G. R. A.; Scheidt, W. R.; Sturhahn, W.; Alp, E. E.; Durbin, S. M.; Sage, J. T.

    2004-01-01

    We use quantitative experimental and theoretical approaches to characterize the vibrational dynamics of the Fe atom in porphyrins designed to model heme protein active sites. Nuclear resonance vibrational spectroscopy (NRVS) yields frequencies, amplitudes, and directions for 57Fe vibrations in a series of ferrous nitrosyl porphyrins, which provide a benchmark for evaluation of quantum chemical vibrational calculations. Detailed normal mode predictions result from DFT calculations on ferrous n...

  17. Quantitative Membrane Electrostatics with the Atomic Force Microscope

    OpenAIRE

    Yang, Yi; Mayer, Kathryn M.; Hafner, Jason H.

    2006-01-01

    The atomic force microscope (AFM) is sensitive to electric double layer interactions in electrolyte solutions, but provides only a qualitative view of interfacial electrostatics. We have fully characterized silicon nitride probe tips and other experimental parameters to allow a quantitative electrostatic analysis by AFM, and we have tested the validity of a simple analytical force expression through numerical simulations. As a test sample, we have measured the effective surface charge density...

  18. Quantitative immunoassay of Treponema denticola serovar C in adult periodontitis.

    OpenAIRE

    Simonson, L. G.; Goodman, C H; Morton, H E

    1990-01-01

    Murine monoclonal antibodies specific for Treponema denticola serovar C were produced and characterized in this study. An immunoassay was then developed by using these monoclonal antibodies, and the T. denticola serovar C antigen content of subgingival plaque was quantitated for samples taken from patients with periodontitis and healthy volunteers. The human subgingival plaque samples were grouped by severity of disease and pocket depth measurements at the collection site. The T. denticola se...

  19. Quantitative detection of protein arrays.

    Science.gov (United States)

    Levit-Binnun, Nava; Lindner, Ariel B; Zik, Ory; Eshhar, Zelig; Moses, Elisha

    2003-03-15

    We introduce a quantitative method that utilizes scanning electron microscopy for the analysis of protein chips (SEMPC). SEMPC is based upon counting target-coated gold particles interacting specifically with ligands or proteins arrayed on a derivative microscope glass slide by utilizing backscattering electron detection. As model systems, we quantified the interactions of biotin and streptavidin and of an antibody with its cognate hapten. Our method gives quantitative molecule-counting capabilities with an excellent signal-to-noise ratio and demonstrates a broad dynamic range while retaining easy sample preparation and realistic automation capability. Increased sensitivity and dynamic range are achieved in comparison to currently used array detection methods such as fluorescence, with no signal bleaching, affording high reproducibility and compatibility with miniaturization. Thus, our approach facilitates the determination of the absolute number of molecules bound to the chip rather than their relative amounts, as well as the use of smaller samples.

  20. Quantitative Methods for Teaching Review

    OpenAIRE

    Irina Milnikova; Tamara Shioshvili

    2011-01-01

    A new method of quantitative evaluation of teaching processes is elaborated. On the base of scores data, the method permits to evaluate efficiency of teaching within one group of students and comparative teaching efficiency in two or more groups. As basic characteristics of teaching efficiency heterogeneity, stability and total variability indices both for only one group and for comparing different groups are used. The method is easy to use and permits to rank results of teaching review which...

  1. Quantitative aspects of magnetospheric physics

    International Nuclear Information System (INIS)

    In this book, certain quantitative aspects of magnetospheric physics are described as used at the earth which illustrate the complex and wondrous ways in which the basic laws of physics enable us to obtain an understanding of our surroundings. The author investigates the charged-particle motion in magnetic and electric fields; the trapping region and currents due to trapped particles; the existence of large-scale electric fields in the magnetosphere; the effect of plasma waves on the distribution of particles. (Auth.)

  2. Essays on Quantitative Risk Management

    OpenAIRE

    Fei, Fei

    2013-01-01

    The costly lessons from global crisis in the past decade reinforce the importance as well as challenges of risk management. This thesis explores several core concepts of quantitative risk management and provides further insight. We start with rating migration risk and propose a Mixture of Markov Chains (MMC) model to account for stochastic business cycle effects in credit rating migration risk. The model shows superior in-sample estimation and out-of-sample predication than its rivals. Co...

  3. Quantitative patterns in drone wars

    OpenAIRE

    Garcia-Bernardo, Javier; Dodds, Peter Sheridan; Johnson, Neil F.

    2014-01-01

    Attacks by drones (i.e., unmanned combat air vehicles) continue to generate heated political and ethical debates. Here we examine the quantitative nature of drone attacks, focusing on how their intensity and frequency compare with that of other forms of human conflict. Instead of the power-law distribution found recently for insurgent and terrorist attacks, the severity of attacks is more akin to lognormal and exponential distributions, suggesting that the dynamics underlying drone attacks li...

  4. A quantitative ELISA for dystrophin.

    Science.gov (United States)

    Morris, G E; Ellis, J M; Nguyen, T M

    1993-05-01

    A novel approach to the quantitation of the muscular dystrophy protein, dystrophin, in muscle extracts is described. The two-site ELISA uses two monoclonal antibodies against dystrophin epitopes which lie close together in the rod domain of the dystrophin molecule in order to minimize the effects of dystrophin degradation. Dystrophin is assayed in its native form by extracting with non-ionic detergents and avoiding the use of SDS. PMID:8486926

  5. Quantitative wave-particle duality

    Science.gov (United States)

    Qureshi, Tabish

    2016-07-01

    The complementary wave and particle character of quantum objects (or quantons) was pointed out by Niels Bohr. This wave-particle duality, in the context of the two-slit experiment, is here described not just as two extreme cases of wave and particle characteristics, but in terms of quantitative measures of these characteristics, known to follow a duality relation. A very simple and intuitive derivation of a closely related duality relation is presented, which should be understandable to the introductory student.

  6. Quantitative characterisation of sedimentary grains

    Science.gov (United States)

    Tunwal, Mohit; Mulchrone, Kieran F.; Meere, Patrick A.

    2016-04-01

    Analysis of sedimentary texture helps in determining the formation, transportation and deposition processes of sedimentary rocks. Grain size analysis is traditionally quantitative, whereas grain shape analysis is largely qualitative. A semi-automated approach to quantitatively analyse shape and size of sand sized sedimentary grains is presented. Grain boundaries are manually traced from thin section microphotographs in the case of lithified samples and are automatically identified in the case of loose sediments. Shape and size paramters can then be estimated using a software package written on the Mathematica platform. While automated methodology already exists for loose sediment analysis, the available techniques for the case of lithified samples are limited to cases of high definition thin section microphotographs showing clear contrast between framework grains and matrix. Along with the size of grain, shape parameters such as roundness, angularity, circularity, irregularity and fractal dimension are measured. A new grain shape parameter developed using Fourier descriptors has also been developed. To test this new approach theoretical examples were analysed and produce high quality results supporting the accuracy of the algorithm. Furthermore sandstone samples from known aeolian and fluvial environments from the Dingle Basin, County Kerry, Ireland were collected and analysed. Modern loose sediments from glacial till from County Cork, Ireland and aeolian sediments from Rajasthan, India have also been collected and analysed. A graphical summary of the data is presented and allows for quantitative distinction between samples extracted from different sedimentary environments.

  7. A microfabrication-based approach to quantitative isothermal titration calorimetry.

    Science.gov (United States)

    Wang, Bin; Jia, Yuan; Lin, Qiao

    2016-04-15

    Isothermal titration calorimetry (ITC) directly measures heat evolved in a chemical reaction to determine equilibrium binding properties of biomolecular systems. Conventional ITC instruments are expensive, use complicated design and construction, and require long analysis times. Microfabricated calorimetric devices are promising, although they have yet to allow accurate, quantitative ITC measurements of biochemical reactions. This paper presents a microfabrication-based approach to integrated, quantitative ITC characterization of biomolecular interactions. The approach integrates microfabricated differential calorimetric sensors with microfluidic titration. Biomolecules and reagents are introduced at each of a series of molar ratios, mixed, and allowed to react. The reaction thermal power is differentially measured, and used to determine the thermodynamic profile of the biomolecular interactions. Implemented in a microdevice featuring thermally isolated, well-defined reaction volumes with minimized fluid evaporation as well as highly sensitive thermoelectric sensing, the approach enables accurate and quantitative ITC measurements of protein-ligand interactions under different isothermal conditions. Using the approach, we demonstrate ITC characterization of the binding of 18-Crown-6 with barium chloride, and the binding of ribonuclease A with cytidine 2'-monophosphate within reaction volumes of approximately 0.7 µL and at concentrations down to 2mM. For each binding system, the ITC measurements were completed with considerably reduced analysis times and material consumption, and yielded a complete thermodynamic profile of the molecular interaction in agreement with published data. This demonstrates the potential usefulness of our approach for biomolecular characterization in biomedical applications.

  8. Quantitative Trait Loci in Inbred Lines

    NARCIS (Netherlands)

    Jansen, R.C.

    2001-01-01

    Quantitative traits result from the influence of multiple genes (quantitative trait loci) and environmental factors. Detecting and mapping the individual genes underlying such 'complex' traits is a difficult task. Fortunately, populations obtained from crosses between inbred lines are relatively ide

  9. Quantitative relationships in delphinid neocortex

    DEFF Research Database (Denmark)

    Mortensen, Heidi S.; Pakkenberg, Bente; Dam, Maria;

    2014-01-01

    Possessing large brains and complex behavioral patterns, cetaceans are believed to be highly intelligent. Their brains, which are the largest in the Animal Kingdom and have enormous gyrification compared with terrestrial mammals, have long been of scientific interest. Few studies, however, report...... density in long-finned pilot whales is lower than that in humans, their higher cell number appears to be due to their larger brain. Accordingly, our findings make an important contribution to the ongoing debate over quantitative relationships in the mammalian brain....

  10. Quantitative Characterisation of Surface Texture

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Lonardo, P.M.; Trumpold, H.;

    2000-01-01

    This paper reviews the different methods used to give a quantitative characterisation of surface texture. The paper contains a review of conventional 2D as well as 3D roughness parameters, with particular emphasis on recent international standards and developments. It presents new texture...... characterisation methods, such as fractals, wavelets, change trees and others, including for each method a short review, the parameters that the new methods calculate, and applications of the methods to solve surface problems. The paper contains a discussion on the relevance of the different parameters...

  11. Quantitative evaluation of Alzheimer's disease

    Science.gov (United States)

    Duchesne, S.; Frisoni, G. B.

    2009-02-01

    We propose a single, quantitative metric called the disease evaluation factor (DEF) and assess its efficiency at estimating disease burden in normal, control subjects (CTRL) and probable Alzheimer's disease (AD) patients. The study group consisted in 75 patients with a diagnosis of probable AD and 75 age-matched normal CTRL without neurological or neuropsychological deficit. We calculated a reference eigenspace of MRI appearance from reference data, in which our CTRL and probable AD subjects were projected. We then calculated the multi-dimensional hyperplane separating the CTRL and probable AD groups. The DEF was estimated via a multidimensional weighted distance of eigencoordinates for a given subject and the CTRL group mean, along salient principal components forming the separating hyperplane. We used quantile plots, Kolmogorov-Smirnov and χ2 tests to compare the DEF values and test that their distribution was normal. We used a linear discriminant test to separate CTRL from probable AD based on the DEF factor, and reached an accuracy of 87%. A quantitative biomarker in AD would act as an important surrogate marker of disease status and progression.

  12. Quantitative measurements in capsule endoscopy.

    Science.gov (United States)

    Keuchel, M; Kurniawan, N; Baltes, P; Bandorski, D; Koulaouzidis, A

    2015-10-01

    This review summarizes several approaches for quantitative measurement in capsule endoscopy. Video capsule endoscopy (VCE) typically provides wireless imaging of small bowel. Currently, a variety of quantitative measurements are implemented in commercially available hardware/software. The majority is proprietary and hence undisclosed algorithms. Measurement of amount of luminal contamination allows calculating scores from whole VCE studies. Other scores express the severity of small bowel lesions in Crohn׳s disease or the degree of villous atrophy in celiac disease. Image processing with numerous algorithms of textural and color feature extraction is further in the research focuses for automated image analysis. These tools aim to select single images with relevant lesions as blood, ulcers, polyps and tumors or to omit images showing only luminal contamination. Analysis of motility pattern, size measurement and determination of capsule localization are additional topics. Non-visual wireless capsules transmitting data acquired with specific sensors from the gastrointestinal (GI) tract are available for clinical routine. This includes pH measurement in the esophagus for the diagnosis of acid gastro-esophageal reflux. A wireless motility capsule provides GI motility analysis on the basis of pH, pressure, and temperature measurement. Electromagnetically tracking of another motility capsule allows visualization of motility. However, measurement of substances by GI capsules is of great interest but still at an early stage of development. PMID:26299419

  13. Quantitative risk assessment system (QRAS)

    Science.gov (United States)

    Weinstock, Robert M (Inventor); Smidts, Carol S (Inventor); Mosleh, Ali (Inventor); Chang, Yung-Hsien (Inventor); Swaminathan, Sankaran (Inventor); Groen, Francisco J (Inventor); Tan, Zhibin (Inventor)

    2001-01-01

    A quantitative risk assessment system (QRAS) builds a risk model of a system for which risk of failure is being assessed, then analyzes the risk of the system corresponding to the risk model. The QRAS performs sensitivity analysis of the risk model by altering fundamental components and quantifications built into the risk model, then re-analyzes the risk of the system using the modifications. More particularly, the risk model is built by building a hierarchy, creating a mission timeline, quantifying failure modes, and building/editing event sequence diagrams. Multiplicities, dependencies, and redundancies of the system are included in the risk model. For analysis runs, a fixed baseline is first constructed and stored. This baseline contains the lowest level scenarios, preserved in event tree structure. The analysis runs, at any level of the hierarchy and below, access this baseline for risk quantitative computation as well as ranking of particular risks. A standalone Tool Box capability exists, allowing the user to store application programs within QRAS.

  14. Computer code for quantitative ALARA evaluations

    International Nuclear Information System (INIS)

    A FORTRAN computer code has been developed to simplify the determination of whether dose reduction actions meet the as low as is reasonably achievable (ALARA) criterion. The calculations are based on the methodology developed for the Atomic Industrial Forum. The code is used for analyses of eight types of dose reduction actions, characterized as follows: reduce dose rate, reduce job frequency, reduce productive working time, reduce crew size, increase administrative dose limit for the task, and increase the workers' time utilization and dose utilization through (a) improved working conditions, (b) basic skill training, or (c) refresher training for special skills. For each type of action, two analysis modes are available. The first is a generic analysis in which the program computes potential benefits (in dollars) for a range of possible improvements, e.g., for a range of lower dose rates. Generic analyses are most useful in the planning stage and for evaluating the general feasibility of alternative approaches. The second is a specific analysis in which the potential annual benefits of a specific level of improvement and the annual implementation cost are compared. The potential benefits reflect savings in operational and societal costs that can be realized if occupational radiation doses are reduced. Because the potential benefits depend upon many variables which characterize the job, the workplace, and the workers, there is no unique relationship between the potential dollar savings and the dose savings. The computer code permits rapid quantitative analyses of alternatives and is a tool that supplements the health physicist's professional judgment. The program output provides a rational basis for decision-making and a record of the assumptions employed

  15. No effect of dietary fish oil on renal hemodynamics, tubular function, and renal functional reserve in long-term renal transplant recipients

    DEFF Research Database (Denmark)

    Hansen, J M; Løkkegaard, H; Høy, Carl-Erik;

    1995-01-01

    Dietary supplementation with fish oil rich in n-3 polyunsaturated fatty acids has been suggested to protect the kidney against cyclosporin A (CsA) toxicity. This study investigated the effects of a 10-wk dietary supplementation with fish oil on renal function and renal functional reserve in healthy...... and effective RPF were measured as the renal clearances of (99mTc)DTPA and (131I)hippuran, respectively. Renal tubular function was evaluated by use of the renal clearance of lithium and the urinary excretion of beta 2-microglobulin. Fish oil did not change baseline values of effective RPF, GFR, lithium...... clearance, and urinary excretion of beta 2-microglobulin in any of the groups. The infusion of amino acids induced a comparable increase in GFR, lithium clearance, and the urinary excretion rate of beta 2-microglobulin in all three groups with no additional effect of fish oil. Thus, long-term renal...

  16. Rapid and sustained CD4(+) T-cell-independent immunity from adenovirus-encoded vaccine antigens

    DEFF Research Database (Denmark)

    Holst, Peter J; Bartholdy, Christina; Buus, Anette Stryhn;

    2007-01-01

    Many novel vaccine strategies rely on recombinant viral vectors for antigen delivery, and adenovirus vectors have emerged among the most potent of these. In this report, we have compared the immune response induced through priming with adenovirus vector-encoded full-length viral protein...... to that elicited with an adenovirus-encoded minimal epitope covalently linked to beta(2)-microglobulin. We demonstrate that the beta(2)-microglobulin-linked epitope induced an accelerated and augmented CD8(+) T-cell response. Furthermore, the immunity conferred by vaccination with beta(2)-microglobulin...... in the absence of CD4(+) T-cell help were sustained in the long term and able to expand and control a secondary challenge with LCMV. Our results demonstrate that modifications to the antigen used in adenovirus vaccines may be used to improve the induced T-cell response. Such a strategy for CD4(+) T...

  17. Immunological predictors of survival in HIV type 2-infected rural villagers in Guinea-Bissau

    DEFF Research Database (Denmark)

    Jaffar, Shabbar; Van der Loeff, Maarten Schim; Eugen-Olsen, Jesper;

    2005-01-01

    , CD4%, and plasma viral load were associated independently with survival in multivariate analyses. Neopterin and suPAR did not reach statistical significance. These findings suggest that immune activation is central to the pathogenesis of HIV. They also have important implications for resource......We investigated the association between beta2-microglobulin, neopterin, serum levels of soluble urokinase-type plasminogen activator receptor (suPAR), CD4 count, and plasma viremia with survival in 133 HIV-2-infected villagers and 160 controls living in rural Guinea-Bissau. Subjects were recruited...... in 1991 and visited at home every 3-6 months until 1998. Median beta2-microglobulin, neopterin, and suPAR were significantly higher and CD4% significantly lower among HIV-2-infected individuals than controls. Thirty-one HIV-2-infected individuals died and 7 were lost to follow-up. beta2-Microglobulin...

  18. Quantitative multi-modal NDT data analysis

    Energy Technology Data Exchange (ETDEWEB)

    Heideklang, René; Shokouhi, Parisa [Division 8.5, BAM Fed. Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin (Germany)

    2014-02-18

    A single NDT technique is often not adequate to provide assessments about the integrity of test objects with the required coverage or accuracy. In such situations, it is often resorted to multi-modal testing, where complementary and overlapping information from different NDT techniques are combined for a more comprehensive evaluation. Multi-modal material and defect characterization is an interesting task which involves several diverse fields of research, including signal and image processing, statistics and data mining. The fusion of different modalities may improve quantitative nondestructive evaluation by effectively exploiting the augmented set of multi-sensor information about the material. It is the redundant information in particular, whose quantification is expected to lead to increased reliability and robustness of the inspection results. There are different systematic approaches to data fusion, each with its specific advantages and drawbacks. In our contribution, these will be discussed in the context of nondestructive materials testing. A practical study adopting a high-level scheme for the fusion of Eddy Current, GMR and Thermography measurements on a reference metallic specimen with built-in grooves will be presented. Results show that fusion is able to outperform the best single sensor regarding detection specificity, while retaining the same level of sensitivity.

  19. Quantitative framework for assessing indoor radon policy

    International Nuclear Information System (INIS)

    Radon gas in the indoor environment is recognized as a problem of considerable magnitude; likely responsible for 5,000 to 20,000 lung cancer deaths per year in the United States (Cohen, 1978; Nero, 1986). Radon is an inert, radioactive element in the decay chain or uranium-238 which occurs ubiquitously in soil and rock. Radon emanating from the ground enters houses through cracks and porous building materials in the substructure. Depending on characteristics of the housing design, construction and ventilation practices, dangerously high concentrations can result. The U.S. Environmental Protection Agency (EPA) has taken a lead role in addressing the indoor radon problem. Their strategy is to work with the States and the private sector to characterize the extent of exposure in problem areas and identify alternative actions to reduce health risks. Since radon poses a risk that occurs in private homes, the responsibility for testing and remediation lies largely with the homeowner. This paper presents a quantitative framework to analyze indoor radon policy on a regional scale. A model is developed which describes regional radon risk reduction in terms of the percentage of homeowners in the region who decide to monitor their homes, the likelihood of homeowners taking alternative remedial actions, and the effectiveness of remediation methods in lowering radon concentrations. Different government policies are analyzed in terms of their potential effect on model parameters and resulting risk reductions

  20. Controlled surface chemistries and quantitative cell response

    Science.gov (United States)

    Plant, Anne L.

    2002-03-01

    Living cells experience a large number of signaling cues from their extracellular matrix. As a result of these inputs, a variety of intracellular signaling pathways are apparently initiated simultaneously. The vast array of alternative responses that result from the integration of these inputs suggests that it may be reasonable to look for cellular response not as an 'on' or 'off' condition but as a distribution of responses. A difficult challenge is to determine whether variations in responses from individual cells arise from the complexity of intracellular signals or are due to variations in the cell culture environment. By controlling surface chemistry so that every cell 'sees' the same chemical and physical environment, we can begin to assess how the distribution of cell response is affected strictly by changes in the chemistry of the cell culture surface. Using the gene for green fluorescent protein linked to the gene for the promoter of the extracellular matrix protein, tenascin, we can easily probe the end product in a signaling pathway that is purported to be linked to surface protein chemistry and to cell shape. Cell response to well-controlled, well-characterized, and highly reproducible surfaces prepared using soft lithography techniques are compared with more conventional ways of preparing extracellular matrix proteins for cell culture. Using fluorescence microscopy and image analysis of populations of cells on these surfaces, we probe quantitatively the relationship between surface chemistry, cell shape and variations in gene expression endpoint.

  1. A quantitative fitness analysis workflow.

    Science.gov (United States)

    Banks, A P; Lawless, C; Lydall, D A

    2012-01-01

    Quantitative Fitness Analysis (QFA) is an experimental and computational workflow for comparing fitnesses of microbial cultures grown in parallel(1,2,3,4). QFA can be applied to focused observations of single cultures but is most useful for genome-wide genetic interaction or drug screens investigating up to thousands of independent cultures. The central experimental method is the inoculation of independent, dilute liquid microbial cultures onto solid agar plates which are incubated and regularly photographed. Photographs from each time-point are analyzed, producing quantitative cell density estimates, which are used to construct growth curves, allowing quantitative fitness measures to be derived. Culture fitnesses can be compared to quantify and rank genetic interaction strengths or drug sensitivities. The effect on culture fitness of any treatments added into substrate agar (e.g. small molecules, antibiotics or nutrients) or applied to plates externally (e.g. UV irradiation, temperature) can be quantified by QFA. The QFA workflow produces growth rate estimates analogous to those obtained by spectrophotometric measurement of parallel liquid cultures in 96-well or 200-well plate readers. Importantly, QFA has significantly higher throughput compared with such methods. QFA cultures grow on a solid agar surface and are therefore well aerated during growth without the need for stirring or shaking. QFA throughput is not as high as that of some Synthetic Genetic Array (SGA) screening methods(5,6). However, since QFA cultures are heavily diluted before being inoculated onto agar, QFA can capture more complete growth curves, including exponential and saturation phases(3). For example, growth curve observations allow culture doubling times to be estimated directly with high precision, as discussed previously(1). Here we present a specific QFA protocol applied to thousands of S. cerevisiae cultures which are automatically handled by robots during inoculation, incubation and

  2. Quantitative computed tomography imaging of airway remodeling in severe asthma.

    Science.gov (United States)

    Grenier, Philippe A; Fetita, Catalin I; Brillet, Pierre-Yves

    2016-02-01

    Asthma is a heterogeneous condition and approximately 5-10% of asthmatic subjects have severe disease associated with structure changes of the airways (airway remodeling) that may develop over time or shortly after onset of disease. Quantitative computed tomography (QCT) imaging of the tracheobronchial tree and lung parenchyma has improved during the last 10 years, and has enabled investigators to study the large airway architecture in detail and assess indirectly the small airway structure. In severe asthmatics, morphologic changes in large airways, quantitatively assessed using 2D-3D airway registration and recent algorithms, are characterized by airway wall thickening, luminal narrowing and bronchial stenoses. Extent of expiratory gas trapping, quantitatively assessed using lung densitometry, may be used to assess indirectly small airway remodeling. Investigators have used these quantitative imaging techniques in order to attempt severity grading of asthma, and to identify clusters of asthmatic patients that differ in morphologic and functional characteristics. Although standardization of image analysis procedures needs to be improved, the identification of remodeling pattern in various phenotypes of severe asthma and the ability to relate airway structures to important clinical outcomes should help target treatment more effectively. PMID:26981458

  3. Carnegie Stages 20, 22 and 23: A Quantitative Perspective

    Directory of Open Access Journals (Sweden)

    Maria Aimée Vila Bormey

    2015-06-01

    Full Text Available Background: today, studying the quantitative morphology of the embryonic period in depth is a necessity due to the real prospect of implementing the procedures of prenatal medicine earlier in gestation for better assessment of growth and development at this stage.Objective: to determine quantitative indicators of growth at the stages within the eighth week of the human embryonic period. Methods: a cross-sectional study involving 17 human embryos from abortions using Misoprostol was conducted with prior informed consent. Eight macroscopic morphometric variables were analysed based on the maximum diameters of the body areas, weight and length. The statistical processing included the descriptive analysis of each variable by stage, the weekly average and correlation analysis. The stages 20, 22 and 23 were morphometrically characterized as well as the week eight in general. Results: significant correlations between variables were found. At the eighth week, all variables showed increases from one stage to another proportional to the length of the embryo. The predominance of the cephalic region in the embryonic anatomy, followed by the abdominal and the thoracic regions was quantitatively confirmed. The dominant plane in all regions was the anteroposterior, although the majority of average diameter increases towards the end of week eight occurred in the lateral plane indicating a growth remodeling. Conclusions: the increase in weight and skull-spine length found constitutes a quantitative restatement of the accelerated growth at the stages analysed.

  4. Quantitative photoacoustic elastography in humans

    Science.gov (United States)

    Hai, Pengfei; Zhou, Yong; Gong, Lei; Wang, Lihong V.

    2016-06-01

    We report quantitative photoacoustic elastography (QPAE) capable of measuring Young's modulus of biological tissue in vivo in humans. By combining conventional PAE with a stress sensor having known stress-strain behavior, QPAE can simultaneously measure strain and stress, from which Young's modulus is calculated. We first demonstrate the feasibility of QPAE in agar phantoms with different concentrations. The measured Young's modulus values fit well with both the empirical expectation based on the agar concentrations and those measured in an independent standard compression test. Next, QPAE was applied to quantify the Young's modulus of skeletal muscle in vivo in humans, showing a linear relationship between muscle stiffness and loading. The results demonstrated the capability of QPAE to assess the absolute elasticity of biological tissue noninvasively in vivo in humans, indicating its potential for tissue biomechanics studies and clinical applications.

  5. Innovations in Quantitative Risk Management

    CERN Document Server

    Scherer, Matthias; Zagst, Rudi

    2015-01-01

    Quantitative models are omnipresent –but often controversially discussed– in todays risk management practice. New regulations, innovative financial products, and advances in valuation techniques provide a continuous flow of challenging problems for financial engineers and risk managers alike. Designing a sound stochastic model requires finding a careful balance between parsimonious model assumptions, mathematical viability, and interpretability of the output. Moreover, data requirements and the end-user training are to be considered as well. The KPMG Center of Excellence in Risk Management conference Risk Management Reloaded and this proceedings volume contribute to bridging the gap between academia –providing methodological advances– and practice –having a firm understanding of the economic conditions in which a given model is used. Discussed fields of application range from asset management, credit risk, and energy to risk management issues in insurance. Methodologically, dependence modeling...

  6. Quantitative patterns in drone wars

    Science.gov (United States)

    Garcia-Bernardo, Javier; Dodds, Peter Sheridan; Johnson, Neil F.

    2016-02-01

    Attacks by drones (i.e., unmanned combat air vehicles) continue to generate heated political and ethical debates. Here we examine the quantitative nature of drone attacks, focusing on how their intensity and frequency compare with that of other forms of human conflict. Instead of the power-law distribution found recently for insurgent and terrorist attacks, the severity of attacks is more akin to lognormal and exponential distributions, suggesting that the dynamics underlying drone attacks lie beyond these other forms of human conflict. We find that the pattern in the timing of attacks is consistent with one side having almost complete control, an important if expected result. We show that these novel features can be reproduced and understood using a generative mathematical model in which resource allocation to the dominant side is regulated through a feedback loop.

  7. Qualitative and Quantitative Sentiment Proxies

    DEFF Research Database (Denmark)

    Zhao, Zeyan; Ahmad, Khurshid

    2015-01-01

    Sentiment analysis is a content-analytic investigative framework for researchers, traders and the general public involved in financial markets. This analysis is based on carefully sourced and elaborately constructed proxies for market sentiment and has emerged as a basis for analysing movements...... in stock prices and the associated traded volume. This approach is particularly helpful just before and after the onset of market volatility. We use an autoregressive framework for predicting the overall changes in stock prices by using investor sentiment together with lagged variables of prices...... and trading volumes. The case study we use is a small market index (Danish Stock Exchange Index, OMXC 20, together with prevailing sentiment in Denmark, to evaluate the impact of sentiment on OMXC 20. Furthermore, we introduce a rather novel and quantitative sentiment proxy, that is the use of the index...

  8. Quantitative evaluation of dermatological antiseptics.

    Science.gov (United States)

    Leitch, C S; Leitch, A E; Tidman, M J

    2015-12-01

    Topical antiseptics are frequently used in dermatological management, yet evidence for the efficacy of traditional generic formulations is often largely anecdotal. We tested the in vitro bactericidal activity of four commonly used topical antiseptics against Staphylococcus aureus, using a modified version of the European Standard EN 1276, a quantitative suspension test for evaluation of the bactericidal activity of chemical disinfectants and antiseptics. To meet the standard for antiseptic effectiveness of EN 1276, at least a 5 log10 reduction in bacterial count within 5 minutes of exposure is required. While 1% benzalkonium chloride and 6% hydrogen peroxide both achieved a 5 log10 reduction in S. aureus count, neither 2% aqueous eosin nor 1 : 10 000 potassium permanganate showed significant bactericidal activity compared with control at exposure periods of up to 1 h. Aqueous eosin and potassium permanganate may have desirable astringent properties, but these results suggest they lack effective antiseptic activity, at least against S. aureus.

  9. Quantitative analysis of Boehm's GC

    Institute of Scientific and Technical Information of China (English)

    GUAN Xue-tao; ZHANG Yuan-rui; GOU Xiao-gang; CHENG Xu

    2003-01-01

    The term garbage collection describes the automated process of finding previously allocated memorythatis no longer in use in order to make the memory available to satisfy subsequent allocation requests. Wehave reviewed existing papers and implementations of GC, and especially analyzed Boehm' s C codes, which isa real-time mark-sweep GC running under Linux and ANSI C standard. In this paper, we will quantitatively an-alyze the performance of different configurations of Boehm' s collector subjected to different workloads. Reportedmeasurements demonstrate that a refined garbage collector is a viable alternative to traditional explicit memorymanagement techniques, even for low-level languages. It is more a trade-off for certain system than an all-or-nothing proposition.

  10. Automated quantitative analysis for pneumoconiosis

    Science.gov (United States)

    Kondo, Hiroshi; Zhao, Bin; Mino, Masako

    1998-09-01

    Automated quantitative analysis for pneumoconiosis is presented. In this paper Japanese standard radiographs of pneumoconiosis are categorized by measuring the area density and the number density of small rounded opacities. And furthermore the classification of the size and shape of the opacities is made from the measuring of the equivalent radiuses of each opacity. The proposed method includes a bi- level unsharp masking filter with a 1D uniform impulse response in order to eliminate the undesired parts such as the images of blood vessels and ribs in the chest x-ray photo. The fuzzy contrast enhancement is also introduced in this method for easy and exact detection of small rounded opacities. Many simulation examples show that the proposed method is more reliable than the former method.

  11. Quantitative evaluation of dermatological antiseptics.

    Science.gov (United States)

    Leitch, C S; Leitch, A E; Tidman, M J

    2015-12-01

    Topical antiseptics are frequently used in dermatological management, yet evidence for the efficacy of traditional generic formulations is often largely anecdotal. We tested the in vitro bactericidal activity of four commonly used topical antiseptics against Staphylococcus aureus, using a modified version of the European Standard EN 1276, a quantitative suspension test for evaluation of the bactericidal activity of chemical disinfectants and antiseptics. To meet the standard for antiseptic effectiveness of EN 1276, at least a 5 log10 reduction in bacterial count within 5 minutes of exposure is required. While 1% benzalkonium chloride and 6% hydrogen peroxide both achieved a 5 log10 reduction in S. aureus count, neither 2% aqueous eosin nor 1 : 10 000 potassium permanganate showed significant bactericidal activity compared with control at exposure periods of up to 1 h. Aqueous eosin and potassium permanganate may have desirable astringent properties, but these results suggest they lack effective antiseptic activity, at least against S. aureus. PMID:26456933

  12. Quantitative analysis of qualitative images

    Science.gov (United States)

    Hockney, David; Falco, Charles M.

    2005-03-01

    We show optical evidence that demonstrates artists as early as Jan van Eyck and Robert Campin (c1425) used optical projections as aids for producing their paintings. We also have found optical evidence within works by later artists, including Bermejo (c1475), Lotto (c1525), Caravaggio (c1600), de la Tour (c1650), Chardin (c1750) and Ingres (c1825), demonstrating a continuum in the use of optical projections by artists, along with an evolution in the sophistication of that use. However, even for paintings where we have been able to extract unambiguous, quantitative evidence of the direct use of optical projections for producing certain of the features, this does not mean that paintings are effectively photographs. Because the hand and mind of the artist are intimately involved in the creation process, understanding these complex images requires more than can be obtained from only applying the equations of geometrical optics.

  13. GPC and quantitative phase imaging

    Science.gov (United States)

    Palima, Darwin; Bañas, Andrew Rafael; Villangca, Mark Jayson; Glückstad, Jesper

    2016-03-01

    Generalized Phase Contrast (GPC) is a light efficient method for generating speckle-free contiguous optical distributions using binary-only or analog phase levels. It has been used in applications such as optical trapping and manipulation, active microscopy, structured illumination, optical security, parallel laser marking and labelling and recently in contemporary biophotonics applications such as for adaptive and parallel two-photon optogenetics and neurophotonics. We will present our most recent GPC developments geared towards these applications. We first show a very compact static light shaper followed by the potential of GPC for biomedical and multispectral applications where we experimentally demonstrate the active light shaping of a supercontinuum laser over most of the visible wavelength range. Finally, we discuss how GPC can be advantageously applied for Quantitative Phase Imaging (QPI).

  14. Quantitative analysis of endogenous compounds.

    Science.gov (United States)

    Thakare, Rhishikesh; Chhonker, Yashpal S; Gautam, Nagsen; Alamoudi, Jawaher Abdullah; Alnouti, Yazen

    2016-09-01

    Accurate quantitative analysis of endogenous analytes is essential for several clinical and non-clinical applications. LC-MS/MS is the technique of choice for quantitative analyses. Absolute quantification by LC/MS requires preparing standard curves in the same matrix as the study samples so that the matrix effect and the extraction efficiency for analytes are the same in both the standard and study samples. However, by definition, analyte-free biological matrices do not exist for endogenous compounds. To address the lack of blank matrices for the quantification of endogenous compounds by LC-MS/MS, four approaches are used including the standard addition, the background subtraction, the surrogate matrix, and the surrogate analyte methods. This review article presents an overview these approaches, cite and summarize their applications, and compare their advantages and disadvantages. In addition, we discuss in details, validation requirements and compatibility with FDA guidelines to ensure method reliability in quantifying endogenous compounds. The standard addition, background subtraction, and the surrogate analyte approaches allow the use of the same matrix for the calibration curve as the one to be analyzed in the test samples. However, in the surrogate matrix approach, various matrices such as artificial, stripped, and neat matrices are used as surrogate matrices for the actual matrix of study samples. For the surrogate analyte approach, it is required to demonstrate similarity in matrix effect and recovery between surrogate and authentic endogenous analytes. Similarly, for the surrogate matrix approach, it is required to demonstrate similar matrix effect and extraction recovery in both the surrogate and original matrices. All these methods represent indirect approaches to quantify endogenous compounds and regardless of what approach is followed, it has to be shown that none of the validation criteria have been compromised due to the indirect analyses. PMID

  15. Optimization of quantitative infrared analysis

    Science.gov (United States)

    Duerst, Richard W.; Breneman, W. E.; Dittmar, Rebecca M.; Drugge, Richard E.; Gagnon, Jim E.; Pranis, Robert A.; Spicer, Colleen K.; Stebbings, William L.; Westberg, J. W.; Duerst, Marilyn D.

    1994-01-01

    A number of industrial processes, especially quality assurance procedures, accept information on relative quantities of components in mixtures, whenever absolute values for the quantitative analysis are unavailable. These relative quantities may be determined from infrared intensity ratios even though known standards are unavailable. Repeatability [vs precisionhl in quantitative analysis is a critical parameter for meaningful results. In any given analysis, multiple runs provide "answers" with a certain standard deviation. Obviously, the lower the standard deviation, the better the precision. In attempting to minimize the standard deviation and thus improve precision, we need to delineate which contributing factors we have control over (such as sample preparation techniques, data analysis methodology) and which factors we have little control over (environmental and instrument noise, for example). For a given set of conditions, the best instrumental precision achievable on an IR instrument should be determinable. Traditionally, the term "signal-to-noise" (S/N) has been used for a single spectrum, realizing that S/N improves with an increase in number of scans coadded for generation of that single spectrum. However, the S/N ratio does not directly reflect the precision achievable for an absorbing band. We prefer to use the phrase "maximum achievable instrument precision" (MAIP), which is equivalent to the minimum relative standard deviation for a given peak (either height or area) in spectra. For a specific analysis, the analyst should have in mind the desired precision. Only if the desired precision is less than the MA1P will the analysis be feasible. Once the MAIP is established, other experimental procedures may be modified to improve the analytical precision, if it is below that which is expected (the MAIP).

  16. Quantitative wood anatomy - practical guidelines

    Directory of Open Access Journals (Sweden)

    Georg evon Arx

    2016-06-01

    Full Text Available Quantitative wood anatomy analyzes the variability of xylem anatomical features in trees, shrubs and herbaceous species to address research questions related to plant functioning, growth and environment. Among the more frequently considered anatomical features are lumen dimensions and wall thickness of conducting cells, fibers and several ray properties. The structural properties of each xylem anatomical feature are mostly fixed once they are formed, and define to a large extent its functionality, including transport and storage of water, nutrients, sugars and hormones, and providing mechanical support. The anatomical features can often be localized within an annual growth ring, which allows to establish intra-annual past and present structure-function relationships and its sensitivity to environmental variability. However, there are many methodological obstacles to overcome when aiming at producing (large data sets of xylem anatomical data.Here we describe the different steps from wood sample collection to xylem anatomical data, provide guidance and identify pitfalls, and present different image-analysis tools for the quantification of anatomical features, in particular conducting cells. We show that each data production step from sample collection in the field, microslide preparation in the lab, image capturing through an optical microscope and image analysis with specific tools can readily introduce measurement errors between 5 to 30% and more, whereby the magnitude usually increases the smaller the anatomical features. Such measurement errors – if not avoided or corrected – may make it impossible to extract meaningful xylem anatomical data in light of the rather small range of variability in many anatomical features as observed, for example, within time series of individual plants. Following a rigid protocol and quality control as proposed in this paper is thus mandatory to use quantitative data of xylem anatomical features as a powerful

  17. Quantitative linkage genome scan for atopy in a large collection of Caucasian families

    DEFF Research Database (Denmark)

    Webb, BT; van den Oord, E; Akkari, A;

    2007-01-01

    Quantitative phenotypes correlated with a complex disorder offer increased power to detect linkage in comparison to affected-unaffected classifications. Asthma is a complex disorder characterized by periods of bronchial obstruction and increased bronchial hyper reactivity. In childhood and early...... report represents one of the biggest genome scans so far reported for asthma related phenotypes. This study also demonstrates the utility of increased sample sizes and quantitative phenotypes in linkage analysis of complex disorders....

  18. Adjustments to the preanalytical phase of quantitative cell-free DNA analysis

    OpenAIRE

    Abel Jacobus Bronkhorst; Janine Aucamp; Piet J. Pretorius

    2015-01-01

    Evaluating the kinetics of cell-free DNA (cfDNA) in the blood of cancer patients could be a strong auxiliary component to the molecular characterization of cfDNA, but its potential clinical significance is obscured by the absence of an analytical consensus. To utilize quantitative cfDNA assessment with confidence, it is crucial that the preanalytical phase is standardized. In a previous publication, several preanalytical variables that may affect quantitative measurements of cfDNA were identi...

  19. Quantitative bound entanglement in two-qutrit states

    Science.gov (United States)

    Sentís, Gael; Eltschka, Christopher; Siewert, Jens

    2016-08-01

    Among the many facets of quantum correlations, bound entanglement has remained one the most enigmatic phenomena, despite the fact that it was discovered in the early days of quantum information. Even its detection has proven to be difficult, let alone its precise quantitative characterization. In this work, we present the exact quantification of entanglement for a two-parameter family of highly symmetric two-qutrit mixed states, which contains a sizable part of bound entangled states. We achieve this by explicitly calculating the convex-roof extensions of the linear entropy as well as the concurrence for every state within the family. Our results provide a benchmark for future quantitative studies of bipartite entanglement in higher-dimensional systems.

  20. High-Content Screening for Quantitative Cell Biology.

    Science.gov (United States)

    Mattiazzi Usaj, Mojca; Styles, Erin B; Verster, Adrian J; Friesen, Helena; Boone, Charles; Andrews, Brenda J

    2016-08-01

    High-content screening (HCS), which combines automated fluorescence microscopy with quantitative image analysis, allows the acquisition of unbiased multiparametric data at the single cell level. This approach has been used to address diverse biological questions and identify a plethora of quantitative phenotypes of varying complexity in numerous different model systems. Here, we describe some recent applications of HCS, ranging from the identification of genes required for specific biological processes to the characterization of genetic interactions. We review the steps involved in the design of useful biological assays and automated image analysis, and describe major challenges associated with each. Additionally, we highlight emerging technologies and future challenges, and discuss how the field of HCS might be enhanced in the future.

  1. Mass spectrometry as a quantitative tool in plant metabolomics.

    Science.gov (United States)

    Jorge, Tiago F; Mata, Ana T; António, Carla

    2016-10-28

    Metabolomics is a research field used to acquire comprehensive information on the composition of a metabolite pool to provide a functional screen of the cellular state. Studies of the plant metabolome include the analysis of a wide range of chemical species with very diverse physico-chemical properties, and therefore powerful analytical tools are required for the separation, characterization and quantification of this vast compound diversity present in plant matrices. In this review, challenges in the use of mass spectrometry (MS) as a quantitative tool in plant metabolomics experiments are discussed, and important criteria for the development and validation of MS-based analytical methods provided.This article is part of the themed issue 'Quantitative mass spectrometry'. PMID:27644967

  2. Quantitation of Leishmania lipophosphoglycan repeat units by capillary electrophoresis.

    Science.gov (United States)

    Barron, Tamara L; Turco, Salvatore J

    2006-04-01

    The glycosylphosphatidylinositol (GPI)-anchored lipophosphoglycan (LPG) of Leishmania is the dominant cell surface glycoconjugate of these pathogenic parasites. LPG is structurally characterized by a series of phosphoglycan repeat units. Determining the number of repeat units per LPG molecule has proven difficult using current technologies, such as mass spectrometry. As an alternative method to quantitate the number of repeat units in LPG, a procedure based on capillary electrophoretic analysis of the proportion of mannose to 2,5-anhydromannose (derived from the nonacetylated glucosamine of the GPI anchor of LPG) was developed. The CE-based technique is sensitive and relatively rapid compared to GC-MS-based protocols. Its application was demonstrated in quantitating the number of LPG repeat units from several species of Leishmania as well as from two life-cycle stages of these organisms. PMID:16310310

  3. Quantitative approach for damage detection of reinforced concrete frames

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The objective of this paper is to provide an analytical basis for the quantitative evaluation of damage to a reinforced concrete structure based on the vibration data obtained by using the damage detection technique. A partial reinforced concrete system of a weak beam/strong column moment frame is chosen as an example. A pushover analysis is carried out in order to numerically examine both the story shear-relative displacement characteristics and the associated damage level. In the analysis, a two dimensional nonlinear finite element analysis is employed considering several constitutive models. As a result, the degradation of the stiffness at the damaged story is characterized in association with the story relative displacement. It is also pointed out that the rotation angle of the column-base is highly correlated with the story relative displacement. Based on the analytical findings, quantitative approaches for a structural health monitoring system are suggested considering both the current sensor technologies and those available in the future.

  4. Experimental bath engineering for quantitative studies of quantum control

    CERN Document Server

    Soare, A; Hayes, D; Zhen, X; Jarratt, M C; Uys, H; Biercuk, M J

    2014-01-01

    We develop and demonstrate a technique to engineer universal unitary baths in quantum systems. Using the correspondence between unitary decoherence due to ambient environmental noise and errors in a control system for quantum bits, we show how a wide variety of relevant classical error models may be realized through In-Phase/Quadrature modulation on a vector signal generator producing a resonant carrier signal. We demonstrate our approach through high-bandwidth modulation of the 12.6 GHz carrier appropriate for trapped $^{171}$Yb$^{+}$ ions. Experiments demonstrate the reduction of coherent lifetime in the system in the presence of an engineered bath, with the observed $T_{2}$ scaling as predicted by a quantitative model described herein. These techniques form the basis of a toolkit for quantitative tests of quantum control protocols, helping experimentalists characterize the performance of their quantum coherent systems.

  5. Urinary retinol binding protein is a marker of the extent of interstitial kidney fibrosis.

    Directory of Open Access Journals (Sweden)

    Nicolas Pallet

    Full Text Available Currently, a non-invasive method to estimate the degree of interstitial fibrosis (IF in chronic kidney disease is not available in routine. The aim of our study was to evaluate the diagnostic performance of the measurement of urinary low molecular weight (LMW protein concentrations as a method to determine the extent of IF. The urines specimen from 162 consecutive patients who underwent renal biopsy were used in the analysis. Numerical quantification software based on the colorimetric analysis of fibrous areas was used to assess the percentage IF. Total proteinuria, albuminuria, and the urinary levels of retinol binding protein (RBP, alpha1-microglobulin (α1MG, beta 2-microglobulin (β2MG, transferrin, and IgG immunoglobulins were measured. There was a significant correlation between the degree of IF and the RBP/creatinine (creat ratio (R2: 0.11, p25% of the parenchyma was 95% when using a threshold of 20 mg/g creat. In conclusion, RBP appears to be a quantitative and non-invasive marker for the independent prediction of the extent of kidney IF. Because methods for the measurement of urinary RBP are available in most clinical chemistry departments, RBP measurement is appealing for implementation in the routine care of patients with chronic kidney disease.

  6. Diabetic gastroparesis in association with autonomic neuropathy and microvasculopathy.

    Directory of Open Access Journals (Sweden)

    Koçkar MC

    2002-10-01

    Full Text Available Gastroparesis is a frequent and sometimes life-threatening complication of diabetes mellitus. Autonomic neuropathy seems to be one of the most important mechanisms underlying this entity, together with the other probable pathologies. The present study was performed in order to identify an alternative to gastric scintigraphy as a screening test. The gastric emptying times of 60 subjects (Group 1: 20 insulin-dependent patients, Group 2: 20 non-insulin-dependent diabetes mellitus patients, and Group 3: 20 healthy volunteers were monitored by gastric scintigraphy. Perception thresholds for cold, heat, and vibration were tested by a quantitative sensory test, and QTc dispersions were calculated from standard electrocardiography recordings. In addition, fasting blood glucose, hemoglobin A1c and urine beta2-microglobulin and microalbumin concentrations were determined for the patient groups. Funduscopic examination was performed by an independent ophthalmologist. Gastroparesis was determined in both patient groups, regardless of fasting blood glucose and hemoglobin A1c concentrations. A strong correlation was observed between nephropathy, retinopathy, and cardiac autonomic denervation (QTc and gastroparesis. In conclusion, retinal and renal microvasculopathy parameters and cardiac autonomic function tests may be useful for screening diabetic patients for gastroparesis.

  7. A multicenter photoprovocation study to identify potential biomarkers by global peptide profiling in cutaneous lupus erythematosus.

    Science.gov (United States)

    Calderon, C; Zucht, H D; Kuhn, A; Wozniacka, A; Szepietowski, J C; Nyberg, F; Weichenthal, M; Piantone, A; Budde, P

    2015-11-01

    Cutaneous lupus erythematosus (CLE) is an inflammatory autoimmune skin disease in which abnormal photosensitivity is an important pathogenetic factor but is difficult to predict, creating a challenge in determining treatment efficacy. Although photosensitivity in CLE patients may change over time, photoprovocation testing with ultraviolet (UV) A and UVB irradiation can be a helpful tool to explore differences between responders and nonresponders during photoprovocation. To identify biomarkers that could substitute for the clinical endpoint lesion development, we performed a global peptidomics profiling analysis of CLE subjects in a controlled photoprovocation study. Plasma and skin biopsy samples were collected before and after UV-irradiation from 13 healthy volunteers and 47 CLE subjects. Twenty-two of the 47 CLE subjects developed skin lesions. The samples were analyzed using a label-free quantitative peptidomics workflow combined with univariate and multivariate statistical analyses. The primary finding was identification of a specific plasma peptide signature separating responders versus nonresponders at baseline. The peptide signature consisted of beta 2-microglobulin (B2MG), human beta-defensin-1, and peptides derived from CD99, polymeric immunoglobulin receptor, and immunoglobulin kappa light chains. In skin, elevated B2MG levels correlated with lesion formation. Our results show that the peptidome is a rich source of potential biomarkers for predicting photosensitivity in CLE.

  8. Cystatin B-deficient mice have increased expression of apoptosis and glial activation genes

    Energy Technology Data Exchange (ETDEWEB)

    Lieuallen, Kimberly; Pennacchio, Len A.; Park, Morgan; Myers, Richard M.; Lennon, Gregory G.

    2001-07-05

    Loss-of-function mutations in the cystatin B (Cstb) gene cause a neurological disorder known as Unverricht Lundborg disease (EPM1) in human patients. Mice that lack Cstb provide a mammalian model for EPM1 by displaying progressive ataxia and myoclonic seizures. We analyzed RNAs from brains of Cstb-deficient mice by using modified differential display, oligonucleotide microarray hybridization and quantitative reverse transcriptase polymerase chain reaction to examine the molecular consequences of the lack of Cstb. We identified seven genes that have consistently increased transcript levels in neurological tissues from the knockout mice. These genes are cathepsin S, C1q B-chain of complement (C1qB), beta-2-microglobulin, glial fibrillary acidic protein (Gfap), apolipoprotein D, fibronectin 1 and metallothionein II, which are expected to be involved in increased proteolysis, apoptosis and glial activation. The molecular changes in Cstb-deficient mice are consistent with the pathology found in the mouse model and may provide clues towards the identification of therapeutic points of intervention for EPM1 patients.

  9. Selection of reference genes for studies of porcine endometrial gene expression on gestational day 12.

    Science.gov (United States)

    Wang, Shouqi; Li, Jiaqi; Zhang, Ailing; Liu, Manqing; Zhang, Hao

    2011-05-01

    Comparing gene expression patterns in the endometrium on gestational day 12 (GD12) between Erhualian (ER) and Landrace×Large White (LL) pigs is helpful to understand the biological mechanisms of fecundity. Selecting genes that have stable expression levels as the internal standards in a comparative study is essential for identifying real gene-specific variation by quantitative RT-PCR (qRT-PCR). Five genes expressed in sow endometria on GD12 were evaluated for their suitability as internal control for relative quantification by qRT-PCR. These genes were beta-actin (ACTB), beta-2-microglobulin (B2M), phosphoglycerate kinase 1 (PGK1), RNA polymerase II polypeptide G (RPG), and ribosomal protein S20 (RPS20), which represent different functional classes. Our results indicated that ACTB, B2M, and PGK1 were not suitable as internal standards for normalization because of their huge variability between the two breeds. RPS20 and RPG were most stable, and the former is recommended to serve as the internal standard when the use of multiple housekeeping genes is unpractical. PMID:21501585

  10. Validation of reference genes for RT-qPCR analysis of CYP4T expression in crucian carp

    Directory of Open Access Journals (Sweden)

    Fei Mo

    2014-09-01

    Full Text Available Reference genes are commonly used for normalization of target gene expression during RT-qPCR analysis. However, no housekeeping genes or reference genes have been identified to be stable across different tissue types or under different experimental conditions. To identify the most suitable reference genes for RT-qPCR analysis of target gene expression in the hepatopancreas of crucian carp (Carassius auratus under various conditions (sex, age, water temperature, and drug treatments, seven reference genes, including beta actin (ACTB, beta-2 microglobulin (B2M, embryonic elongation factor-1 alpha (EEF1A, glyceraldehyde phosphate dehydrogenase (GAPDH, alpha tubulin (TUBA, ribosomal protein l8 (RPL8 and glucose-6-phosphate dehydrogenase (G6PDH, were evaluated in this study. The stability and ranking of gene expression were analyzed using three different statistical programs: GeNorm, Normfinder and Bestkeeper. The expression errors associated with selection of the genes were assessed by the relative quantity of CYP4T. The results indicated that all the seven genes exhibited variability under the experimental conditions of this research, and the combination of ACTB/TUBA/EEF1A or of ACTB/EEF1A was the best candidate that raised the accuracy of quantitative analysis of gene expression. The findings highlighted the importance of validation of housekeeping genes for research on gene expression under different conditions of experiment and species.

  11. Isoelectric focusing of urinary metallothionein.

    Science.gov (United States)

    Felley-Bosco, E; Hunziker, P E; Savolainen, H

    1990-05-01

    Isoelectric focusing of human urinary metallothionein at a pH range of 4.8 to 7.0 yielded a single protein band with a pI of 5.57 which co-migrated with authentic purified metallothionein I from human liver. Minimum pretreatment of the urine samples (160 ml) was needed. The preparatory steps included sample concentration with the original protein, enriched from 69 +/- 23 micrograms/ml to 2.0 +/- 1.4 mg/ml (+/- SD; n = 9), followed by heat treatment at 80 degrees C for 5 min (2.4 +/- 1.7 mg protein/ml). After focusing, the gels were stained with silver and the lanes were scanned with a laser scanner. Peak areas were used for quantitation with commercial beta 2-microglobulin as a standard. The urinary metallothionein ranged from 1.0 to 2.6 nmol/mmol creatinine, which is comparable with values reached by radio-immunoassay.

  12. Identification of suitable reference genes in bone marrow stromal cells from osteoarthritic donors.

    Science.gov (United States)

    Schildberg, Theresa; Rauh, Juliane; Bretschneider, Henriette; Stiehler, Maik

    2013-11-01

    Bone marrow stromal cells (BMSCs) are key cellular components for musculoskeletal tissue engineering strategies. Furthermore, recent data suggest that BMSCs are involved in the development of Osteoarthritis (OA) being a frequently occurring degenerative joint disease. Reliable reference genes for the molecular evaluation of BMSCs derived from donors exhibiting OA as a primary co-morbidity have not been reported on yet. Hence, the aim of the study was to identify reference genes suitable for comparative gene expression analyses using OA-BMSCs. Passage 1 bone marrow derived BMSCs were isolated from n=13 patients with advanced stage idiopathic hip osteoarthritis and n=15 age-matched healthy donors. The expression of 31 putative reference genes was analyzed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) using a commercially available TaqMan(®) assay. Calculating the coefficient of variation (CV), mRNA expression stability was determined and afterwards validated using geNorm and NormFinder algorithms. Importin 8 (IPO8), TATA box binding protein (TBP), and cancer susceptibility candidate 3 (CASC3) were identified as the most stable reference genes. Notably, commonly used reference genes, e.g. beta-actin (ACTB) and beta-2-microglobulin (B2M) were among the most unstable genes. For normalization of gene expression data of OA-BMSCs the combined use of IPO8, TBP, and CASC3 gene is recommended.

  13. Characterization of housekeeping genes in zebrafish: male-female differences and effects of tissue type, developmental stage and chemical treatment

    Directory of Open Access Journals (Sweden)

    Callard Gloria V

    2008-11-01

    Full Text Available Abstract Background Research using the zebrafish model has experienced a rapid growth in recent years. Although real-time reverse transcription PCR (QPCR, normalized to an internal reference ("housekeeping" gene, is a frequently used method for quantifying gene expression changes in zebrafish, many commonly used housekeeping genes are known to vary with experimental conditions. To identify housekeeping genes that are stably expressed under different experimental conditions, and thus suitable as normalizers for QPCR in zebrafish, the present study evaluated the expression of eight commonly used housekeeping genes as a function of stage and hormone/toxicant exposure during development, and by tissue type and sex in adult fish. Results QPCR analysis was used to quantify mRNA levels of bactin1, tubulin alpha 1(tuba1, glyceraldehyde-3-phosphate dehydrogenase (gapdh, glucose-6-phosphate dehydrogenase (g6pd, TATA-box binding protein (tbp, beta-2-microglobulin (b2m, elongation factor 1 alpha (elfa, and 18s ribosomal RNA (18s during development (2 – 120 hr postfertilization, hpf; in different tissue types (brain, eye, liver, heart, muscle, gonads of adult males and females; and after treatment of embryos/larvae (24 – 96 hpf with commonly used vehicles for administration and agents that represent known environmental endocrine disruptors. All genes were found to have some degree of variability under the conditions tested here. Rank ordering of expression stability using geNorm analysis identified 18s, b2m, and elfa as most stable during development and across tissue types, while gapdh, tuba1, and tpb were the most variable. Following chemical treatment, tuba1, bactin1, and elfa were the most stably expressed whereas tbp, 18s, and b2m were the least stable. Data also revealed sex differences that are gene- and tissue-specific, and treatment effects that are gene-, vehicle- and ligand-specific. When the accuracy of QPCR analysis was tested using

  14. Quantitative Magnetic Resonance Imaging of Cortical Multiple Sclerosis Pathology

    Directory of Open Access Journals (Sweden)

    Christine L. Tardif

    2012-01-01

    Full Text Available Although significant improvements have been made regarding the visualization and characterization of cortical multiple sclerosis (MS lesions using magnetic resonance imaging (MRI, cortical lesions (CL continue to be under-detected in vivo, and we have a limited understanding of the causes of GM pathology. The objective of this study was to characterize the MRI signature of CLs to help interpret the changes seen in vivo and elucidate the factors limiting their visualization. A quantitative 3D high-resolution (350 μm isotropic MRI study at 3 Tesla of a fixed post mortem cerebral hemisphere from a patient with MS is presented in combination with matched immunohistochemistry. Type III subpial lesions are characterized by an increase in T1, T2 and M0, and a decrease in MTR in comparison to the normal appearing cortex (NAC. All quantitative MR parameters were associated with cortical GM myelin content, while T1 showed the strongest correlation. The histogram analysis showed extensive overlap between CL and NAC for all MR parameters and myelin content. This is due to the poor contrast in myelin content between CL and NAC in comparison to the variability in myelo-architecture throughout the healthy cortex. This latter comparison is highlighted by the representation of T1 times on cortical surfaces at several laminar depths.

  15. Computationally driven, quantitative experiments discover genes required for mitochondrial biogenesis.

    Directory of Open Access Journals (Sweden)

    David C Hess

    2009-03-01

    Full Text Available Mitochondria are central to many cellular processes including respiration, ion homeostasis, and apoptosis. Using computational predictions combined with traditional quantitative experiments, we have identified 100 proteins whose deficiency alters mitochondrial biogenesis and inheritance in Saccharomyces cerevisiae. In addition, we used computational predictions to perform targeted double-mutant analysis detecting another nine genes with synthetic defects in mitochondrial biogenesis. This represents an increase of about 25% over previously known participants. Nearly half of these newly characterized proteins are conserved in mammals, including several orthologs known to be involved in human disease. Mutations in many of these genes demonstrate statistically significant mitochondrial transmission phenotypes more subtle than could be detected by traditional genetic screens or high-throughput techniques, and 47 have not been previously localized to mitochondria. We further characterized a subset of these genes using growth profiling and dual immunofluorescence, which identified genes specifically required for aerobic respiration and an uncharacterized cytoplasmic protein required for normal mitochondrial motility. Our results demonstrate that by leveraging computational analysis to direct quantitative experimental assays, we have characterized mutants with subtle mitochondrial defects whose phenotypes were undetected by high-throughput methods.

  16. Quantitative analysis of PET measurements in tumors

    International Nuclear Information System (INIS)

    The positron emission tomograhpy (PET) has been used for the evaluation of the characteristics of various tumors. The role of PET in oncology has been evolved from a pure research tool to a methodology of enormous clinical potential. The unique characteristics of PET imaging make sophisticated quantitation possible. Several quantitative methods, such as standardized uptake values (SUV), simplifield quantitation method, Patlak graphical analysis, and Sokoloff's glucose metabolism measurement, have been used in the field of oncology. However, each quantitative method has limitations of its own. For example, the SUV has been used as a quantitative index of glucose metabolism for tumor classification and monitoring response to treatment, even though it depends on blood glucose level, body configuration of patient, and scanning time. The quantitative methods of PET are reviewed and strategy for implementing these methods are presented

  17. The effect of short-term glucagon infusion on kidney function in normal man

    DEFF Research Database (Denmark)

    Parving, H H; Noer, J; Kehlet, H;

    1977-01-01

    Kidney function was studied in six normal males before and during a 2 h glucagon (10 ng/kg/min) infusion. The following variables were determined during each 20 min clearance period; glomerular filtration rate (GFR), renal plasma-flow (RPF) , filtration fraction (FF), urinary albumin and beta2......-microglobulin-excretion rates. Glucagon infusion resulted in a fourfold increase in plasma glucagon concentration. The infusion induced a significant increase in GFR (+9%), FF (+9%) and urinary beta2-microglobulin excretion rate (+32%), (p less than 0.01). RPF and urinary albumin excretion rates were...

  18. Amyloidosis associated with dialysis. Dialyseassoziierte Amyloidosteopathie - radiologische Aspekte

    Energy Technology Data Exchange (ETDEWEB)

    Schadmand, S.; Klose, K.J. (Mainz Univ. (Germany, F.R.). Inst. fuer Klinische Strahlenkunde); Wandel, E. (Mainz Univ. (Germany, F.R.). 1. Medizinische Klinik und Poliklinik)

    1991-06-01

    Amongst the complications of dialysis, amyloid osteopathy is getting increasingly significant. It is due to deposition of {beta}2-microglobulin. To determine the incidence and time of development of this complication, the skeletal radiographs of 185 patients undergoing dialysis, some for up to ten years, were analysed retrospectively. In about 10% of patients, the presence of {beta}2-microglobulin osteopathy may be expected. The radiological features, sites of predilection and differential diagnosis of amyloid osteopathy and of other skeletal changes due to dialysis are discussed. (orig.).

  19. Quantitative imaging of nonlinear shear modulus by combining static elastography and shear wave elastography.

    Science.gov (United States)

    Latorre-Ossa, Heldmuth; Gennisson, Jean-Luc; De Brosses, Emilie; Tanter, Mickaël

    2012-04-01

    The study of new tissue mechanical properties such as shear nonlinearity could lead to better tissue characterization and clinical diagnosis. This work proposes a method combining static elastography and shear wave elastography to derive the nonlinear shear modulus by applying the acoustoelasticity theory in quasi-incompressible soft solids. Results demonstrate that by applying a moderate static stress at the surface of the investigated medium, and by following the quantitative evolution of its shear modulus, it is possible to accurately and quantitatively recover the local Landau (A) coefficient characterizing the shear nonlinearity of soft tissues.

  20. A quantitative philology of introspection

    Directory of Open Access Journals (Sweden)

    Carlos eDiuk

    2012-09-01

    Full Text Available The cultural evolution of introspective thought has been recognized to undergo a drastic change during the middle of the first millennium BC. This period, known as the ``Axial Age'', saw the birth of religions and philosophies still alive in modern culture, as well as the transition from orality to literacy - which led to the hypothesis of a link between introspection and literacy. Here we set out to examine the evolution of introspection in the Axial Age, studying the cultural record of the Greco-Roman and Judeo-Christian literary traditions. Using a statistical measure of semantic similarity, we identify a single ``arrow of time'' in the Old and New Testaments of the Bible, and a more complex non-monotonic dynamics in the Greco-Roman tradition reflecting the rise and fall of the respective societies. A comparable analysis of the 20th century cultural record shows a steady increase in the incidence of introspective topics, punctuated by abrupt declines during and preceding the First and Second World Wars. Our results show that (a it is possible to devise a consistent metric to quantify the history of a high-level concept such as introspection, cementing the path for a new quantitative philology and (b to the extent that it is captured in the cultural record, the increased ability of human thought for self-reflection that the Axial Age brought about is still heavily determined by societal contingencies beyond the orality-literacy nexus.

  1. Quantitative relationships in delphinid neocortex

    Directory of Open Access Journals (Sweden)

    Heidi S Mortensen

    2014-11-01

    Full Text Available Possessing large brains and complex behavioural patterns, cetaceans are believed to be highly intelligent. Their brains, which are the largest in the Animal Kingdom and have enormous gyrification compared with terrestrial mammals, have long been of scientific interest. Few studies, however, report total number of brain cells in cetaceans, and even fewer have used unbiased counting methods. In this study, using stereological methods, we estimated the total number of cells in the long-finned pilot whale (Globicephala melas brain. For the first time, we show that a species of dolphin has more neocortical neurons than in any mammal studied to date including humans. These cell numbers are compared across various mammals with different brain sizes, and the function of possessing many neurons is discussed. We found that the long-finned pilot whale neocortex has approximately 37.2 × 109 neurons, which is almost twice as many as humans, and 127 × 109 glial cells. Thus, the absolute number of neurons in the human neocortex is not correlated with the superior cognitive abilities of humans (at least compared to cetaceans as has previously been hypothesized. However, as neuron density in long-finned pilot whales is lower than that in humans, their higher cell number appears to be due to their larger brain. Accordingly, our findings make an important contribution to the ongoing debate over quantitative relationships in the mammalian brain.

  2. Quantitative relationships in delphinid neocortex.

    Science.gov (United States)

    Mortensen, Heidi S; Pakkenberg, Bente; Dam, Maria; Dietz, Rune; Sonne, Christian; Mikkelsen, Bjarni; Eriksen, Nina

    2014-01-01

    Possessing large brains and complex behavioral patterns, cetaceans are believed to be highly intelligent. Their brains, which are the largest in the Animal Kingdom and have enormous gyrification compared with terrestrial mammals, have long been of scientific interest. Few studies, however, report total number of brain cells in cetaceans, and even fewer have used unbiased counting methods. In this study, using stereological methods, we estimated the total number of cells in the neocortex of the long-finned pilot whale (Globicephala melas) brain. For the first time, we show that a species of dolphin has more neocortical neurons than any mammal studied to date including humans. These cell numbers are compared across various mammals with different brain sizes, and the function of possessing many neurons is discussed. We found that the long-finned pilot whale neocortex has approximately 37.2 × 10(9) neurons, which is almost twice as many as humans, and 127 × 10(9) glial cells. Thus, the absolute number of neurons in the human neocortex is not correlated with the superior cognitive abilities of humans (at least compared to cetaceans) as has previously been hypothesized. However, as neuron density in long-finned pilot whales is lower than that in humans, their higher cell number appears to be due to their larger brain. Accordingly, our findings make an important contribution to the ongoing debate over quantitative relationships in the mammalian brain. PMID:25505387

  3. Submarine Pipeline Routing Risk Quantitative Analysis

    Institute of Scientific and Technical Information of China (English)

    徐慧; 于莉; 胡云昌; 王金英

    2004-01-01

    A new method for submarine pipeline routing risk quantitative analysis was provided, and the study was developed from qualitative analysis to quantitative analysis.The characteristics of the potential risk of the submarine pipeline system were considered, and grey-mode identification theory was used. The study process was composed of three parts: establishing the indexes system of routing risk quantitative analysis, establishing the model of grey-mode identification for routing risk quantitative analysis, and establishing the standard of mode identification result. It is shown that this model can directly and concisely reflect the hazard degree of the routing through computing example, and prepares the routing selection for the future.

  4. Principles of Quantitative Estimation of the Chaperone-Like Activity

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Molecular chaperones are able to interact with unfolded states of the protein molecule preventing their aggregation and facilitating folding of the polypeptide chain into the native structure. An understanding of the mechanism of protein aggregation is required to estimate the efficiency of action of chaperones in the test-systems based on the suppression of aggregation of protein substrates. The kinetic regimes of aggregation of proteins are discussed. The analysis of the aggregation kinetics of proteins shows that after passing the lag phase, aggregation follows, as a rule, first order kinetics. The quantitative characterization methods of the ability of chaperones to prevent aggregation of protein substrates have been elaborated.

  5. Etiology and Diagnosis of Major Depression - A Novel Quantitative Approach

    DEFF Research Database (Denmark)

    Ottesen, Johnny T.

    2013-01-01

    Background: Classical psychiatric opinions are relative uncertain and treatment results are not impressive when dealing with major depression. Depression is related to the endocrine system, but despite much effort a good quantitative measure for characterizing depression has not yet emerged......, however, the healthy system is able to deal with such elevated (suppressed) levels by compensating through suppressing (stimulating) the other component. In contrast the O-index shows that depressed subjects are incapable of making such compensation to a satisfactory degree. We illustrate how the O...

  6. Quantitative studies of multiphoton ionization using tunable VUV radiation

    International Nuclear Information System (INIS)

    The storage ring free electron laser makes studies of multiphoton ionization in the vacuum ultraviolet possible. At relatively low laser intensities one can study two-photon resonant three-photon ionization of atoms in a regime where perturbation theory works well. In this regime cross sections for the multiphoton processes can be measured accurately and then used for sensitive, quantitative detection of atoms. At higher intensities higher-order processes such as multiple ionization can take place. The tunability, variable pulse length, and well characterized spatial distribution of the FEL is important in unraveling the mechanisms of these processes

  7. Neurocognitive deficit in schizophrenia: a quantitative review of the evidence.

    Science.gov (United States)

    Heinrichs, R W; Zakzanis, K K

    1998-07-01

    The neurocognitive literature on test performance in schizophrenia is reviewed quantitatively. The authors report 22 mean effect sizes from 204 studies to index schizophrenia versus control differences in global and selective verbal memory, nonverbal memory, bilateral and unilateral motor performance, visual and auditory attention, general intelligence, spatial ability, executive function, language, and interhemispheric tactile-transfer test performance. Moderate to large raw effect sizes (d > .60) were obtained for all 22 neurocognitive test variables, and none of the associated confidence intervals included zero. The results indicate that schizophrenia is characterized by a broadly based cognitive impairment, with varying degrees of deficit in all ability domains measured by standard clinical tests. PMID:9673998

  8. Quantitative paleogeography and accretionary history, northern Appalachians

    Energy Technology Data Exchange (ETDEWEB)

    Pluijm, B.A. van der; Voo, R. van der (Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Geological Sciences)

    1992-01-01

    Ongoing paleomagnetic work on Early and Middle Paleozoic units provides quantitative data on paleogeography, latitudinal separation and latitudinal drift rates of tectonic elements that characterize the history of the northern segment of the Appalachian orogen. Following rifting and opening of Iapetus, the southern margin of Laurentia moved from ca 15S in the Ordovician to ca. 30S in the late Silurian: the northern margin of Avalon drifted northward (separate from Gondwana) from > 50--30S during the same time interval. Paleolatitudes from volcanic units of the intervening Central Mobile Belt that yield primary magnetizations are: Newfoundland: Ordovician arc-back arc basin: 11[degree]S; Ordovician ocean island/arc: 31[degree]S; Silurian continental cover: Botwood Gp: 24[degree]S, Springdale Gp: 17[degree]S New Brunswick: Ordovician rift-subduction complex: 53[degree]S. Maine: Munsungun Volcanic Terrane 18[degree]S; Winterville Volcanic Terrane 15--20[degree]S; upper part Lunksoos Composite Terrane: 20[degree]S. The Ordovician results indicate several near-Laurentian volcanic terranes and back-arc basins, landward-dipping subduction complexes on opposite margins of Iapetus, and intra-Iapetus ocean islands/arcs. Silurian paleogeographic and tectonostratigraphic data show that closure of Iapetus and progressive outboard accretion in the northern portion of the Appalachian orogen was complete by the late Silurian. This closure is accompanied by considerable Ordovician to Early Silurian left-lateral strike slip and subsequent right-lateral displacement based on the relative positions of Laurentia, Avalon and Gondwana in Early and Middle Paleozoic times.

  9. Low molecular weight oligomers of amyloid peptides display β-barrel conformations: A replica exchange molecular dynamics study in explicit solvent

    Science.gov (United States)

    De Simone, Alfonso; Derreumaux, Philippe

    2010-04-01

    The self-assembly of proteins and peptides into amyloid fibrils is connected to over 40 pathological conditions including neurodegenerative diseases and systemic amyloidosis. Diffusible, low molecular weight protein and peptide oligomers that form in the early steps of aggregation appear to be the harmful cytotoxic species in the molecular etiology of these diseases. So far, the structural characterization of these oligomers has remained elusive owing to their transient and dynamic features. We here address, by means of full atomistic replica exchange molecular dynamics simulations, the energy landscape of heptamers of the amyloidogenic peptide NHVTLSQ from the beta-2 microglobulin protein. The simulations totaling 5 μs show that low molecular weight oligomers in explicit solvent consist of β-barrels in equilibrium with amorphous states and fibril-like assemblies. The results, also accounting for the influence of the pH on the conformational properties, provide a strong evidence of the formation of transient β-barrel assemblies in the early aggregation steps of amyloid-forming systems. Our findings are discussed in terms of oligomers cytotoxicity.

  10. [Cardiac amyloidosis].

    Science.gov (United States)

    Hoyer, Caroline; Angermann, Christiane E; Knop, Stefan; Ertl, Georg; Störk, Stefan

    2008-03-15

    Amyloidoses are a heterogeneous group of multisystem disorders, which are characterized by an extracellular deposition of amyloid fibrils. Typically affected are the heart, liver, kidneys, and nervous system. More than half of the patients die due to cardiac involvement. Clinical signs of cardiac amyloidosis are edema of the lower limbs, hepatomegaly, ascites and elevated jugular vein pressure, frequently in combination with dyspnea. There can also be chest pain, probably due to microvessel disease. Dysfunction of the autonomous nervous system or arrhythmias may cause low blood pressure, dizziness, or recurrent syncope. The AL amyloidosis caused by the deposition of immunoglobulin light chains is the most common form. It can be performed by monoclonal gammopathy. The desirable treatment therapy consists of high-dose melphalan therapy twice followed by autologous stem cell transplantation. Due to the high peritransplantation mortality, selection of appropriate patients is mandatory. The ATTR amyloidosis is an autosomal dominant disorder caused by the amyloidogenic form of transthyretin, a plasmaprotein that is synthesized in the liver. Therefore, liver transplantation is the only curative therapy. The symptomatic treatment of cardiac amyloidosis is based on the current guidelines for chronic heart failure according to the patient's New York Heart Association (NYHA) state. Further types of amyloidosis with possible cardiac involvement comprise the senile systemic amyloidosis caused by the wild-type transthyretin, secondary amyloidosis after chronic systemic inflammation, and the beta(2)-microglobulin amyloidosis after long-term dialysis treatment. PMID:18344065

  11. Identification and quantitation of signal molecule-dependent protein phosphorylation

    KAUST Repository

    Groen, Arnoud J.

    2013-09-03

    Phosphoproteomics is a fast-growing field that aims at characterizing phosphorylated proteins in a cell or a tissue at a given time. Phosphorylation of proteins is an important regulatory mechanism in many cellular processes. Gel-free phosphoproteome technique involving enrichment of phosphopeptide coupled with mass spectrometry has proven to be invaluable to detect and characterize phosphorylated proteins. In this chapter, a gel-free quantitative approach involving 15N metabolic labelling in combination with phosphopeptide enrichment by titanium dioxide (TiO2) and their identification by MS is described. This workflow can be used to gain insights into the role of signalling molecules such as cyclic nucleotides on regulatory networks through the identification and quantification of responsive phospho(proteins). © Springer Science+Business Media New York 2013.

  12. Quantitative metagenomic analyses based on average genome size normalization

    DEFF Research Database (Denmark)

    Frank, Jeremy Alexander; Sørensen, Søren Johannes

    2011-01-01

    Over the past quarter-century, microbiologists have used DNA sequence information to aid in the characterization of microbial communities. During the last decade, this has expanded from single genes to microbial community genomics, or metagenomics, in which the gene content of an environment can...... provide not just a census of the community members but direct information on metabolic capabilities and potential interactions among community members. Here we introduce a method for the quantitative characterization and comparison of microbial communities based on the normalization of metagenomic data...... by estimating average genome sizes. This normalization can relieve comparative biases introduced by differences in community structure, number of sequencing reads, and sequencing read lengths between different metagenomes. We demonstrate the utility of this approach by comparing metagenomes from two different...

  13. Development of Quantitative electron nano-diffraction

    NARCIS (Netherlands)

    Kumar, V.

    2009-01-01

    This thesis is a step towards development of quantitative parallel beam electron nano-diffraction (PBED). It is focused on the superstructure determination of zig-zag and zig-zig NaxCoO2 and analysis of charge distribution in the two polymorphs Nb12O29 using PBED. It has been shown that quantitative

  14. Development and Measurement of Preschoolers' Quantitative Knowledge

    Science.gov (United States)

    Geary, David C.

    2015-01-01

    The collection of studies in this special issue make an important contribution to our understanding and measurement of the core cognitive and noncognitive factors that influence children's emerging quantitative competencies. The studies also illustrate how the field has matured, from a time when the quantitative competencies of infants and young…

  15. Applications of quantitative remote sensing to hydrology

    NARCIS (Netherlands)

    Su, Z.; Troch, P.A.A.

    2003-01-01

    In order to quantify the rates of the exchanges of energy and matter among hydrosphere, biosphere and atmosphere, quantitative description of land surface processes by means of measurements at different scales are essential. Quantitative remote sensing plays an important role in this respect. The se

  16. Using Popular Culture to Teach Quantitative Reasoning

    Science.gov (United States)

    Hillyard, Cinnamon

    2007-01-01

    Popular culture provides many opportunities to develop quantitative reasoning. This article describes a junior-level, interdisciplinary, quantitative reasoning course that uses examples from movies, cartoons, television, magazine advertisements, and children's literature. Some benefits from and cautions to using popular culture to teach…

  17. A Primer on Disseminating Applied Quantitative Research

    Science.gov (United States)

    Bell, Bethany A.; DiStefano, Christine; Morgan, Grant B.

    2010-01-01

    Transparency and replication are essential features of scientific inquiry, yet scientific communications of applied quantitative research are often lacking in much-needed procedural information. In an effort to promote researchers dissemination of their quantitative studies in a cohesive, detailed, and informative manner, the authors delineate…

  18. Theory and Practice in Quantitative Genetics

    DEFF Research Database (Denmark)

    Posthuma, Daniëlle; Beem, A Leo; de Geus, Eco J C;

    2003-01-01

    With the rapid advances in molecular biology, the near completion of the human genome, the development of appropriate statistical genetic methods and the availability of the necessary computing power, the identification of quantitative trait loci has now become a realistic prospect for quantitative...... geneticists. We briefly describe the theoretical biometrical foundations underlying quantitative genetics. These theoretical underpinnings are translated into mathematical equations that allow the assessment of the contribution of observed (using DNA samples) and unobserved (using known genetic relationships......) genetic variation to population variance in quantitative traits. Several statistical models for quantitative genetic analyses are described, such as models for the classical twin design, multivariate and longitudinal genetic analyses, extended twin analyses, and linkage and association analyses. For each...

  19. A quantitative approach to evolution of music and philosophy

    International Nuclear Information System (INIS)

    The development of new statistical and computational methods is increasingly making it possible to bridge the gap between hard sciences and humanities. In this study, we propose an approach based on a quantitative evaluation of attributes of objects in fields of humanities, from which concepts such as dialectics and opposition are formally defined mathematically. As case studies, we analyzed the temporal evolution of classical music and philosophy by obtaining data for 8 features characterizing the corresponding fields for 7 well-known composers and philosophers, which were treated with multivariate statistics and pattern recognition methods. A bootstrap method was applied to avoid statistical bias caused by the small sample data set, with which hundreds of artificial composers and philosophers were generated, influenced by the 7 names originally chosen. Upon defining indices for opposition, skewness and counter-dialectics, we confirmed the intuitive analysis of historians in that classical music evolved according to a master–apprentice tradition, while in philosophy changes were driven by opposition. Though these case studies were meant only to show the possibility of treating phenomena in humanities quantitatively, including a quantitative measure of concepts such as dialectics and opposition, the results are encouraging for further application of the approach presented here to many other areas, since it is entirely generic. (paper)

  20. Cleavage entropy as quantitative measure of protease specificity.

    Directory of Open Access Journals (Sweden)

    Julian E Fuchs

    2013-04-01

    Full Text Available A purely information theory-guided approach to quantitatively characterize protease specificity is established. We calculate an entropy value for each protease subpocket based on sequences of cleaved substrates extracted from the MEROPS database. We compare our results with known subpocket specificity profiles for individual proteases and protease groups (e.g. serine proteases, metallo proteases and reflect them quantitatively. Summation of subpocket-wise cleavage entropy contributions yields a measure for overall protease substrate specificity. This total cleavage entropy allows ranking of different proteases with respect to their specificity, separating unspecific digestive enzymes showing high total cleavage entropy from specific proteases involved in signaling cascades. The development of a quantitative cleavage entropy score allows an unbiased comparison of subpocket-wise and overall protease specificity. Thus, it enables assessment of relative importance of physicochemical and structural descriptors in protease recognition. We present an exemplary application of cleavage entropy in tracing substrate specificity in protease evolution. This highlights the wide range of substrate promiscuity within homologue proteases and hence the heavy impact of a limited number of mutations on individual substrate specificity.

  1. Quantitative epistasis analysis and pathway inference from genetic interaction data.

    Directory of Open Access Journals (Sweden)

    Hilary Phenix

    2011-05-01

    Full Text Available Inferring regulatory and metabolic network models from quantitative genetic interaction data remains a major challenge in systems biology. Here, we present a novel quantitative model for interpreting epistasis within pathways responding to an external signal. The model provides the basis of an experimental method to determine the architecture of such pathways, and establishes a new set of rules to infer the order of genes within them. The method also allows the extraction of quantitative parameters enabling a new level of information to be added to genetic network models. It is applicable to any system where the impact of combinatorial loss-of-function mutations can be quantified with sufficient accuracy. We test the method by conducting a systematic analysis of a thoroughly characterized eukaryotic gene network, the galactose utilization pathway in Saccharomyces cerevisiae. For this purpose, we quantify the effects of single and double gene deletions on two phenotypic traits, fitness and reporter gene expression. We show that applying our method to fitness traits reveals the order of metabolic enzymes and the effects of accumulating metabolic intermediates. Conversely, the analysis of expression traits reveals the order of transcriptional regulatory genes, secondary regulatory signals and their relative strength. Strikingly, when the analyses of the two traits are combined, the method correctly infers ~80% of the known relationships without any false positives.

  2. Facegram - Objective quantitative analysis in facial reconstructive surgery.

    Science.gov (United States)

    Gerós, Ana; Horta, Ricardo; Aguiar, Paulo

    2016-06-01

    Evaluation of effectiveness in reconstructive plastic surgery has become an increasingly important asset in comparing and choosing the most suitable medical procedure to handle facial disfigurement. Unfortunately, traditional methods to assess the results of surgical interventions are mostly qualitative and lack information about movement dynamics. Along with this, the few existing methodologies tailored to objectively quantify surgery results are not practical in the medical field due to constraints in terms of cost, complexity and poor suitability to clinical environment. These limitations enforce an urgent need for the creation of a new system to quantify facial movement and allow for an easy interpretation by medical experts. With this in mind, we present here a novel method capable of quantitatively and objectively assess complex facial movements, using a set of morphological, static and dynamic measurements. For this purpose, RGB-D cameras are used to acquire both color and depth images, and a modified block matching algorithm, combining depth and color information, was developed to track the position of anatomical landmarks of interest. The algorithms are integrated into a user-friendly graphical interface and the analysis outcomes are organized into an innovative medical tool, named facegram. This system was developed in close collaboration with plastic surgeons and the methods were validated using control subjects and patients with facial paralysis. The system was shown to provide useful and detailed quantitative information (static and dynamic) making it an appropriate solution for objective quantitative characterization of facial movement in a clinical environment. PMID:26994664

  3. A quantitative approach to evolution of music and philosophy

    Science.gov (United States)

    Vieira, Vilson; Fabbri, Renato; Travieso, Gonzalo; Oliveira, Osvaldo N., Jr.; da Fontoura Costa, Luciano

    2012-08-01

    The development of new statistical and computational methods is increasingly making it possible to bridge the gap between hard sciences and humanities. In this study, we propose an approach based on a quantitative evaluation of attributes of objects in fields of humanities, from which concepts such as dialectics and opposition are formally defined mathematically. As case studies, we analyzed the temporal evolution of classical music and philosophy by obtaining data for 8 features characterizing the corresponding fields for 7 well-known composers and philosophers, which were treated with multivariate statistics and pattern recognition methods. A bootstrap method was applied to avoid statistical bias caused by the small sample data set, with which hundreds of artificial composers and philosophers were generated, influenced by the 7 names originally chosen. Upon defining indices for opposition, skewness and counter-dialectics, we confirmed the intuitive analysis of historians in that classical music evolved according to a master-apprentice tradition, while in philosophy changes were driven by opposition. Though these case studies were meant only to show the possibility of treating phenomena in humanities quantitatively, including a quantitative measure of concepts such as dialectics and opposition, the results are encouraging for further application of the approach presented here to many other areas, since it is entirely generic.

  4. Brain microstructure mapping using quantitative and diffusion MRI

    International Nuclear Information System (INIS)

    This thesis is focused on the human brain microstructure mapping using quantitative and diffusion MRI. The T1/T2 quantitative imaging relies on sequences dedicated to the mapping of T1 and T2 relaxation times. Their variations within the tissue are linked to the presence of different water compartments defined by a specific organization of the tissue at the cell scale. Measuring these parameters can help, therefore, to better characterize the brain microstructure. The dMRI, on the other hand, explores the brownian motion of water molecules in the brain tissue, where the water molecules' movement is constrained by natural barriers, such as cell membranes. Thus, the information on their displacement carried by the dMRI signal gives access to the underlying cyto-architecture. Combination of these two modalities is, therefore, a promising way to probe the brain tissue microstructure. The main goal of the present thesis is to set up the methodology to study the microstructure of the white matter of the human brain in vivo. The first part includes the acquisition of a unique MRI database of 79 healthy subjects (the Archi/CONNECT), which includes anatomical high resolution data, relaxometry data, diffusion-weighted data at high spatio-angular resolution and functional data. This database has allowed us to build the first atlas of the anatomical connectivity of the healthy brain through the automatic segmentation of the major white matter bundles, providing an appropriate anatomical reference for the white matter to study individually the quantitative parameters along each fascicle, characterizing its microstructure organization. Emphasis was placed on the construction of the first atlas of the T1/T2 profiles along the major white matter pathways. The profiles of the T1 and T2 relaxation times were then correlated to the quantitative profiles computed from the diffusion MRI data (fractional anisotropy, radial and longitudinal diffusivities, apparent diffusion coefficient

  5. Quantitative Sensory Testing in Patients With Postthoracotomy Pain Syndrome

    DEFF Research Database (Denmark)

    Wildgaard, Kim; Ringsted, Thomas K; Kehlet, Henrik;

    2013-01-01

    OBJECTIVES:: Quantitative sensory testing is a reference method for characterization of postsurgical neuropathic components. Correct interpretation of data requires detailed information concerning the validity of the testing methods. The objective of the study was to assess the test-retest variab......OBJECTIVES:: Quantitative sensory testing is a reference method for characterization of postsurgical neuropathic components. Correct interpretation of data requires detailed information concerning the validity of the testing methods. The objective of the study was to assess the test......-retest variability of thermal thresholds in patients (n=14) with the postthoracotomy pain syndrome. METHODS:: Sensory mapping with a metal roller (25°C) on the surgical side delineated an area with cool sensory dysfunction. In this area and in a contralateral area, 4 prespecified sites (2.6 cm) were outlined......, in addition to the maximum pain site on the surgical side. In these total 9 sites, warmth detection threshold, cool detection threshold, and heat pain threshold were assessed. RESULTS:: Comparisons of thermal test-retest assessments did not demonstrate any significant intraside differences. The SDs...

  6. Lessons learned from quantitative dynamical modeling in systems biology.

    Directory of Open Access Journals (Sweden)

    Andreas Raue

    Full Text Available Due to the high complexity of biological data it is difficult to disentangle cellular processes relying only on intuitive interpretation of measurements. A Systems Biology approach that combines quantitative experimental data with dynamic mathematical modeling promises to yield deeper insights into these processes. Nevertheless, with growing complexity and increasing amount of quantitative experimental data, building realistic and reliable mathematical models can become a challenging task: the quality of experimental data has to be assessed objectively, unknown model parameters need to be estimated from the experimental data, and numerical calculations need to be precise and efficient. Here, we discuss, compare and characterize the performance of computational methods throughout the process of quantitative dynamic modeling using two previously established examples, for which quantitative, dose- and time-resolved experimental data are available. In particular, we present an approach that allows to determine the quality of experimental data in an efficient, objective and automated manner. Using this approach data generated by different measurement techniques and even in single replicates can be reliably used for mathematical modeling. For the estimation of unknown model parameters, the performance of different optimization algorithms was compared systematically. Our results show that deterministic derivative-based optimization employing the sensitivity equations in combination with a multi-start strategy based on latin hypercube sampling outperforms the other methods by orders of magnitude in accuracy and speed. Finally, we investigated transformations that yield a more efficient parameterization of the model and therefore lead to a further enhancement in optimization performance. We provide a freely available open source software package that implements the algorithms and examples compared here.

  7. The reproducibility of quantitative measurements in lumbar magnetic resonance imaging of children from the general population

    DEFF Research Database (Denmark)

    Masharawi, Y; Kjær, Per; Bendix, T;

    2008-01-01

    and disc sagittal wedging at L5 (CCC Quantitative lumbar MRI measurements in children from the general population were found to be reproducible indicating a good visualization of immature vertebral anatomic margins on MRIs and an accurate definition of the measurement protocol.......STUDY DESIGN: Quantitative lumbar magnetic resonance imaging (MRI) measurements in children were taken twice and analyzed for intra- and intertester reproducibility. OBJECTIVE: To evaluate the reproducibility of a variety of lumbar quantitative measurements taken from MRIs of children from...... the general population. SUMMARY OF BACKGROUND DATA: The reproducibility of lumbar quantitative measurements has never been tested on MRIs of children from the general population. This is a prerequisite for a reliable anatomic characterization of the immature spine in normal and pathologic conditions. METHODS...

  8. Analysis of archaeological ceramics by total-reflection X-ray fluorescence: Quantitative approaches

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Ruiz, R. [Servicio Interdepartamental de Investigacion, Facultad de Ciencias, Universidad Autonoma de Madrid, Modulo C-9, Laboratorio de TXRF, Crta. Colmenar, Km 15, Cantoblanco, E-28049, Madrid (Spain)], E-mail: ramon.fernandez@uam.es; Garcia-Heras, M. [Grupo de Arqueometria de Vidrios y Materiales Ceramicos, Instituto de Historia, Centro de Ciencias Humanas y Sociales, CSIC, C/ Albasanz, 26-28, 28037 Madrid (Spain)

    2008-09-15

    This paper reports the quantitative methodologies developed for the compositional characterization of archaeological ceramics by total-reflection X-ray fluorescence at two levels. A first quantitative level which comprises an acid leaching procedure, and a second selective level, which seeks to increase the number of detectable elements by eliminating the iron present in the acid leaching procedure. Total-reflection X-ray fluorescence spectrometry has been compared, at a quantitative level, with Instrumental Neutron Activation Analysis in order to test its applicability to the study of this kind of materials. The combination of a solid chemical homogenization procedure previously reported with the quantitative methodologies here presented allows the total-reflection X-ray fluorescence to analyze 29 elements with acceptable analytical recoveries and accuracies.

  9. Composition and Quantitation of Microalgal Lipids by ERETIC 1H NMR Method

    OpenAIRE

    Angelo Fontana; Adele Cutignano; Angela Sardo; Giuliana d'Ippolito; Carmela Gallo; Genoveffa Nuzzo

    2013-01-01

    Accurate characterization of biomass constituents is a crucial aspect of research in the biotechnological application of natural products. Here we report an efficient, fast and reproducible method for the identification and quantitation of fatty acids and complex lipids (triacylglycerols, glycolipids, phospholipids) in microalgae under investigation for the development of functional health products (probiotics, food ingredients, drugs, etc.) or third generation biofuels. The procedure consist...

  10. African swine fever virus excretion patterns in persistently infected animals: A quantitative approach

    NARCIS (Netherlands)

    Carvalho Ferreira, de H.C.; Weesendorp, E.; Elbers, A.R.W.; Bouma, A.; Quak, S.; Stegeman, J.A.; Loeffen, W.L.A.

    2012-01-01

    The continuing circulation of African swine fever (ASF) in Russia and in the Trans-Caucasian countries has led to increased efforts in characterizing the epidemiology of ASF. For a better insight in epidemiology, quantitative data on virus excretion is required. Until now, excretion data has mainly

  11. On Characterizing Particle Shape

    Science.gov (United States)

    Ennis, Bryan J.; Rickman, Douglas; Rollins, A. Brent; Ennis, Brandon

    2014-01-01

    It is well known that particle shape affects flow characteristics of granular materials, as well as a variety of other solids processing issues such as compaction, rheology, filtration and other two-phase flow problems. The impact of shape crosses many diverse and commercially important applications, including pharmaceuticals, civil engineering, metallurgy, health, and food processing. Two applications studied here include the dry solids flow of lunar simulants (e.g. JSC-1, NU-LHT-2M, OB-1), and the flow properties of wet concrete, including final compressive strength. A multi-dimensional generalized, engineering method to quantitatively characterize particle shapes has been developed, applicable to both single particle orientation and multi-particle assemblies. The two-dimension, three dimension inversion problem is also treated, and the application of these methods to DEM model particles will be discussed. In the case of lunar simulants, flow properties of six lunar simulants have been measured, and the impact of particle shape on flowability - as characterized by the shape method developed here -- is discussed, especially in the context of three simulants of similar size range. In the context of concrete processing, concrete construction is a major contributor to greenhouse gas production, of which the major contributor is cement binding loading. Any optimization in concrete rheology and packing that can reduce cement loading and improve strength loading can also reduce currently required construction safety factors. The characterization approach here is also demonstrated for the impact of rock aggregate shape on concrete slump rheology and dry compressive strength.

  12. The mathematics of cancer: integrating quantitative models.

    Science.gov (United States)

    Altrock, Philipp M; Liu, Lin L; Michor, Franziska

    2015-12-01

    Mathematical modelling approaches have become increasingly abundant in cancer research. The complexity of cancer is well suited to quantitative approaches as it provides challenges and opportunities for new developments. In turn, mathematical modelling contributes to cancer research by helping to elucidate mechanisms and by providing quantitative predictions that can be validated. The recent expansion of quantitative models addresses many questions regarding tumour initiation, progression and metastases as well as intra-tumour heterogeneity, treatment responses and resistance. Mathematical models can complement experimental and clinical studies, but also challenge current paradigms, redefine our understanding of mechanisms driving tumorigenesis and shape future research in cancer biology.

  13. MR morphology of triangular fibrocartilage complex: correlation with quantitative MR and biomechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Won C.; Chang, Eric Y.; Chung, Christine B. [VA San Diego Healthcare System, Radiology Service, San Diego, CA (United States); University of California-San Diego, Department of Radiology, San Diego, CA (United States); Ruangchaijatuporn, Thumanoon [Mahidol University, Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine Ramathibodi Hospital, Rachathewi, Bangkok (Thailand); Biswas, Reni; Du, Jiang; Statum, Sheronda [University of California-San Diego, Department of Radiology, San Diego, CA (United States)

    2016-04-15

    To evaluate pathology of the triangular fibrocartilage complex (TFCC) using high-resolution morphologic magnetic resonance (MR) imaging, and compare with quantitative MR and biomechanical properties. Five cadaveric wrists (22-70 years) were imaged at 3 T using morphologic (proton density weighted spin echo, PD FS, and 3D spoiled gradient echo, 3D SPGR) and quantitative MR sequences to determine T2 and T1rho properties. In eight geographic regions, morphology of TFC disc and laminae were evaluated for pathology and quantitative MR values. Samples were disarticulated and biomechanical indentation testing was performed on the distal surface of the TFC disc. On morphologic PD SE images, TFC disc pathology included degeneration and tears, while that of the laminae included degeneration, degeneration with superimposed tear, mucinous transformation, and globular calcification. Punctate calcifications were highly visible on 3D SPGR images and found only in pathologic regions. Disc pathology occurred more frequently in proximal regions of the disc than distal regions. Quantitative MR values were lowest in normal samples, and generally higher in pathologic regions. Biomechanical testing demonstrated an inverse relationship, with indentation modulus being high in normal regions with low MR values. The laminae studied were mostly pathologic, and additional normal samples are needed to discern quantitative changes. These results show technical feasibility of morphologic MR, quantitative MR, and biomechanical techniques to characterize pathology of the TFCC. Quantitative MRI may be a suitable surrogate marker of soft tissue mechanical properties, and a useful adjunct to conventional morphologic MR techniques. (orig.)

  14. Characterization of the oligodeoxynucleotide-mediated inhibition of interferon-gamma-induced major histocompatibility complex class I and intercellular adhesion molecule-1.

    Science.gov (United States)

    Ramanathan, M; Lantz, M; MacGregor, R D; Garovoy, M R; Hunt, C A

    1994-10-01

    The major histocompatibility complex (MHC) Class I and II genes and intercellular adhesion molecule-1 (ICAM-1) are regulated by interferon-gamma in a variety of cell types. We have previously shown that the oligodeoxynucleotide 5'-GGG GTT GGT TGT GTT GGG TGT TGT GT-RNH2 (oligo I) inhibits the interferon-gamma-mediated enhancement of MHC Class I and ICAM-1 proteins in the K562 cell line. We have now investigated the mechanism of action of oligo I and report that it acts by inhibiting the binding of interferon-gamma to cells. We also show that the dose-response curves, the selectivity profile, and the kinetics of oligo I are consistent with this novel mechanism of action. The dose-response curves for oligo I, obtained using antibodies against the MHC Class I heavy chain, beta 2-microglobulin, or ICAM-1, are almost superimposable at each observation time. MHC Class I induction by 6400 units/ml interferon-alpha or interferon-beta or ICAM-1 enhancement by 800 units/ml tumor necrosis factor-alpha is not inhibited by oligo I. However, the synergistic induction of MHC Class I by mixtures of tumor necrosis factor-alpha and interferon-gamma is inhibited. Oligo I belongs to a class of active oligodeoxynucleotides that inhibits interferon-gamma-induced MHC Class I and ICAM-1 in K562 cells. The activity and potency is sequence-dependent, but remarkably different sequences can have comparable effects. The activity of oligo I in the HeLa S3 cell line inhibits the interferon-gamma-mediated enhancement of both ICAM-1 and MHC Class II DR and the interferon-gamma-mediated reduction in transferrin receptor expression. Thus, oligo I appears to specifically inhibit interferon-gamma-induced changes in protein expression, which is consistent with oligo I acting at an early step(s) in the induction process. Taken together, our results show that oligo I exerts its effects by inhibiting the association of interferon-gamma with the cell surface, which is a novel mechanism of action for

  15. Electronic Noses Using Quantitative Artificial Neural Networ

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The present paper covers a new type of electronic nose(e-nose) with a four-sensor array,which has been applied to detecting gases quantitatively in the presence of interference. This e-nose has adapted fundamental aspects of relative error(RE) in changing quantitative analysis into the artificial neural network (ANN).. Thus, both the quantitative and the qualitative requirements for ANN in implementing e-nose can be satisfied. In addition, the e-nose uses only 4 sensors in the sensor array, and can be designed for different usages simply by changing one or two sensor(s). Various gases were tested by this kind of e-nose, including alcohol vapor, CO, liquefied-petrol-gas and CO2. Satisfactory quantitative results were obtained and no qualitative mistake in prediction was observed for the samples being mixed with interference gases.

  16. Instrumentation and quantitative methods of evaluation

    International Nuclear Information System (INIS)

    This report summarizes goals and accomplishments of the research program entitled Instrumentation and Quantitative Methods of Evaluation, during the period January 15, 1989 through July 15, 1991. This program is very closely integrated with the radiopharmaceutical program entitled Quantitative Studies in Radiopharmaceutical Science. Together, they constitute the PROGRAM OF NUCLEAR MEDICINE AND QUANTITATIVE IMAGING RESEARCH within The Franklin McLean Memorial Research Institute (FMI). The program addresses problems involving the basic science and technology that underlie the physical and conceptual tools of radiotracer methodology as they relate to the measurement of structural and functional parameters of physiologic importance in health and disease. The principal tool is quantitative radionuclide imaging. The objective of this program is to further the development and transfer of radiotracer methodology from basic theory to routine clinical practice. The focus of the research is on the development of new instruments and radiopharmaceuticals, and the evaluation of these through the phase of clinical feasibility. 234 refs., 11 figs., 2 tabs

  17. Understanding Pre-Quantitative Risk in Projects

    Science.gov (United States)

    Cooper, Lynne P.

    2011-01-01

    Standard approaches to risk management in projects depend on the ability of teams to identify risks and quantify the probabilities and consequences of these risks (e.g., the 5 x 5 risk matrix). However, long before quantification does - or even can - occur, and long after, teams make decisions based on their pre-quantitative understanding of risk. These decisions can have long-lasting impacts on the project. While significant research has looked at the process of how to quantify risk, our understanding of how teams conceive of and manage pre-quantitative risk is lacking. This paper introduces the concept of pre-quantitative risk and discusses the implications of addressing pre-quantitative risk in projects.

  18. Quantitative risk assessment of durable glass fibers.

    Science.gov (United States)

    Fayerweather, William E; Eastes, Walter; Cereghini, Francesco; Hadley, John G

    2002-06-01

    This article presents a quantitative risk assessment for the theoretical lifetime cancer risk from the manufacture and use of relatively durable synthetic glass fibers. More specifically, we estimate levels of exposure to respirable fibers or fiberlike structures of E-glass and C-glass that, assuming a working lifetime exposure, pose a theoretical lifetime cancer risk of not more than 1 per 100,000. For comparability with other risk assessments we define these levels as nonsignificant exposures. Nonsignificant exposure levels are estimated from (a) the Institute of Occupational Medicine (IOM) chronic rat inhalation bioassay of durable E-glass microfibers, and (b) the Research Consulting Company (RCC) chronic inhalation bioassay of durable refractory ceramic fibers (RCF). Best estimates of nonsignificant E-glass exposure exceed 0.05-0.13 fibers (or shards) per cubic centimeter (cm3) when calculated from the multistage nonthreshold model. Best estimates of nonsignificant C-glass exposure exceed 0.27-0.6 fibers/cm3. Estimates of nonsignificant exposure increase markedly for E- and C-glass when non-linear models are applied and rapidly exceed 1 fiber/cm3. Controlling durable fiber exposures to an 8-h time-weighted average of 0.05 fibers/cm3 will assure that the additional theoretical lifetime risk from working lifetime exposures to these durable fibers or shards is kept below the 1 per 100,000 level. Measured airborne exposures to respirable, durable glass fibers (or shards) in glass fiber manufacturing and fabrication operations were compared with the nonsignificant exposure estimates described. Sampling results for B-sized respirable E-glass fibers at facilities that manufacture or fabricate small-diameter continuous-filament products, from those that manufacture respirable E-glass shards from PERG (process to efficiently recycle glass), from milled fiber operations, and from respirable C-glass shards from Flakeglass operations indicate very low median exposures of 0

  19. Quantitative analysis of learning object repositories

    OpenAIRE

    Ochoa, Xavier; Duval, Erik

    2008-01-01

    This paper conducts the first detailed quantitative study of the process of publication of learning objects in repositories. This process has been often discussed theoretically, but never empirically evaluated. Several question related to basic characteristics of the publication process are raised at the beginning of the paper and answered through quantitative analysis. To provide a wide view of the publication process, this paper analyzes four types of repositories: Learning Object Repositor...

  20. Cancer detection by quantitative fluorescence image analysis.

    Science.gov (United States)

    Parry, W L; Hemstreet, G P

    1988-02-01

    Quantitative fluorescence image analysis is a rapidly evolving biophysical cytochemical technology with the potential for multiple clinical and basic research applications. We report the application of this technique for bladder cancer detection and discuss its potential usefulness as an adjunct to methods used currently by urologists for the diagnosis and management of bladder cancer. Quantitative fluorescence image analysis is a cytological method that incorporates 2 diagnostic techniques, quantitation of nuclear deoxyribonucleic acid and morphometric analysis, in a single semiautomated system to facilitate the identification of rare events, that is individual cancer cells. When compared to routine cytopathology for detection of bladder cancer in symptomatic patients, quantitative fluorescence image analysis demonstrated greater sensitivity (76 versus 33 per cent) for the detection of low grade transitional cell carcinoma. The specificity of quantitative fluorescence image analysis in a small control group was 94 per cent and with the manual method for quantitation of absolute nuclear fluorescence intensity in the screening of high risk asymptomatic subjects the specificity was 96.7 per cent. The more familiar flow cytometry is another fluorescence technique for measurement of nuclear deoxyribonucleic acid. However, rather than identifying individual cancer cells, flow cytometry identifies cellular pattern distributions, that is the ratio of normal to abnormal cells. Numerous studies by others have shown that flow cytometry is a sensitive method to monitor patients with diagnosed urological disease. Based upon results in separate quantitative fluorescence image analysis and flow cytometry studies, it appears that these 2 fluorescence techniques may be complementary tools for urological screening, diagnosis and management, and that they also may be useful separately or in combination to elucidate the oncogenic process, determine the biological potential of tumors

  1. The SAGE Dictionary of Quantitative Management Research

    CERN Document Server

    Moutinho, Professor Luiz A M

    2011-01-01

    A must-have reference resource for quantitative management researchers, the Dictionary contains over 100 entries covering the fundamentals of quantitative methodologies; covering both analysis and implementation and examples of use, as well as detailed graphics to aid understanding. Every entry features: -An introduction to the topic, -Key relevant features, -A worked example, -A concise summary and a selection of further reading suggestions -Cross-references to associated concepts within the dictionary

  2. Quantitative Trait Loci in Inbred Lines

    OpenAIRE

    Jansen, R. C.

    2001-01-01

    Quantitative traits result from the influence of multiple genes (quantitative trait loci) and environmental factors. Detecting and mapping the individual genes underlying such 'complex' traits is a difficult task. Fortunately, populations obtained from crosses between inbred lines are relatively ideal for this - at least far more ideal than livestock and human populations - and true multigenic models are now available and have been applied successfully. In this chapter we will introduce the r...

  3. Strategies for quantitation of phosphoproteomic data

    DEFF Research Database (Denmark)

    Palmisano, Giuseppe; Thingholm, Tine Engberg

    2010-01-01

    strategies in order to study the biological role of protein phosphorylation during disease progression, differentiation or during external stimulation of a cellular system. In this article, a brief summary of the most popular strategies for phosphoproteomic studies is given; however, the main focus...... will be on different quantitation strategies. Methods for metabolic labeling, chemical modification and label-free quantitation and their applicability or inapplicability in phosphoproteomic studies are discussed....

  4. A Quantitative Theory of Credit Scoring

    OpenAIRE

    Xuan Tam; Eric Young; Kartik Athreya

    2013-01-01

    Starting in the early 1990s credit scoring became widespread and central in credit granting decisions. Credit scores are scalar representations of default risk. They are used, in turn, to price credit, and as a result alter household borrowing and default decisions. We build on recent work on defaultable consumer credit under asymmetric information to develop a quantitative theory of credit scores. We construct and solve a rich and quantitatively-disciplined lifecycle model of consumption in ...

  5. Quantitative Methods in Psychology: Inevitable and Useless

    OpenAIRE

    Aaro Toomela

    2010-01-01

    Science begins with the question, what do I want to know? Science becomes science, however, only when this question is justified and the appropriate methodology is chosen for answering the research question. Research question should precede the other questions; methods should be chosen according to the research question and not vice versa. Modern quantitative psychology has accepted method as primary; research questions are adjusted to the methods. For understanding thinking in modern quantit...

  6. Quantitative methods in psychology: inevitable and useless

    Directory of Open Access Journals (Sweden)

    Aaro Toomela

    2010-07-01

    Full Text Available Science begins with the question, what do I want to know? Science becomes science, however, only when this question is justified and the appropriate methodology is chosen for answering the research question. Research question should precede the other questions; methods should be chosen according to the research question and not vice versa. Modern quantitative psychology has accepted method as primary; research questions are adjusted to the methods. For understanding thinking in modern quantitative psychology, two epistemologies should be distinguished: structural-systemic that is based on Aristotelian thinking, and associative-quantitative that is based on Cartesian-Humean thinking. The first aims at understanding the structure that underlies the studied processes; the second looks for identification of cause-effect relationships between the events with no possible access to the understanding of the structures that underlie the processes. Quantitative methodology in particular as well as mathematical psychology in general, is useless for answering questions about structures and processes that underlie observed behaviors. Nevertheless, quantitative science is almost inevitable in a situation where the systemic-structural basis of behavior is not well understood; all sorts of applied decisions can be made on the basis of quantitative studies. In order to proceed, psychology should study structures; methodologically, constructive experiments should be added to observations and analytic experiments.

  7. Image Analysis for Tongue Characterization

    Institute of Scientific and Technical Information of China (English)

    SHENLansun; WEIBaoguo; CAIYiheng; ZHANGXinfeng; WANGYanqing; CHENJing; KONGLingbiao

    2003-01-01

    Tongue diagnosis is one of the essential methods in traditional Chinese medical diagnosis. The ac-curacy of tongue diagnosis can be improved by tongue char-acterization. This paper investigates the use of image anal-ysis techniques for tongue characterization by evaluating visual features obtained from images. A tongue imaging and analysis instrument (TIAI) was developed to acquire digital color tongue images. Several novel approaches are presented for color calibration, tongue area segmentation,quantitative analysis and qualitative description for the colors of tongue and its coating, the thickness and moisture of coating and quantification of the cracks of the toilgue.The overall accuracy of the automatic analysis of the colors of tongue and the thickness of tongue coating exceeds 85%.This work shows the promising future of tongue character-ization.

  8. Analytical nondestructive evaluation for materials characterization

    International Nuclear Information System (INIS)

    Science and technology of nondestructive testing and evaluation has contributed immensely to the safety and productivity of industrial plants. In recent years, nondestructive evaluation (NDE) has emerged as a frontline research area of equal if not greater technological relevance, for materials characterization as well. A comprehensive range of techniques from qualitative nondestructive testing for quality control of engineering products and materials to quantitative NDE for materials characterization is being used by the engineering industry and materials researchers, for better understanding of the manufacturing practices and materials behaviour. Quantitative NDE is considered essential for ensuring fitness for purpose at the start of the life in case the component has been designed using fracture mechanics parameters. Quantitative NDE is also vital for assessing degradation of material during service. Moreover, quantitative NDE enables characterization of dynamics of certain phenomenon (not achievable by destructive test methodologies) leading to better understanding of the performance of materials in relation to unavoidable defects in the materials. As the next logical step, the need for an analytical approach to NDE is felt. The need and motivation for such an approach is addressed and the means to achieve this objective are identified. It is argued that analytical NDE is essential to meet the challenges of characterization, intelligent processing of materials and life prediction of components and plants. These requirements are of significant importance in the context of recent developments in materials engineering, and for enhancing the competitive advantage of Indian engineering industry in the international market. (author). 9 refs., 3 figs

  9. Biophysical characterization of GPCR oligomerization in viro

    DEFF Research Database (Denmark)

    Mathiasen, Signe

    a quantitative characterization of GPCR oligomerization. The assay provided the first quantification of the association energy of the β2 Adrenergic Receptor (β2AR), a prototypical GPCR. Furthermore we directly observed the time-dependent dimerization of β2AR and Cannabinoid receptor 1 at the single molecule...

  10. Quantitative image analysis in sonograms of the thyroid gland

    Science.gov (United States)

    Catherine, Skouroliakou; Maria, Lyra; Aristides, Antoniou; Lambros, Vlahos

    2006-12-01

    High-resolution, real-time ultrasound is a routine examination for assessing the disorders of the thyroid gland. However, the current diagnosis practice is based mainly on qualitative evaluation of the resulting sonograms, therefore depending on the physician's experience. Computerized texture analysis is widely employed in sonographic images of various organs (liver, breast), and it has been proven to increase the sensitivity of diagnosis by providing a better tissue characterization. The present study attempts to characterize thyroid tissue by automatic texture analysis. The texture features that are calculated are based on co-occurrence matrices as they have been proposed by Haralick. The sample consists of 40 patients. For each patient two sonographic images (one for each lobe) are recorded in DICOM format. The lobe is manually delineated in each sonogram, and the co-occurrence matrices for 52 separation vectors are calculated. The texture features extracted from each one of these matrices are: contrast, correlation, energy and homogeneity. Primary component analysis is used to select the optimal set of features. The statistical analysis resulted in the extraction of 21 optimal descriptors. The optimal descriptors are all co-occurrence parameters as the first-order statistics did not prove to be representative of the images characteristics. The bigger number of components depends mainly on correlation for very close or very far distances. The results indicate that quantitative analysis of thyroid sonograms can provide an objective characterization of thyroid tissue.

  11. Quantitative Imaging in Cancer Clinical Trials.

    Science.gov (United States)

    Yankeelov, Thomas E; Mankoff, David A; Schwartz, Lawrence H; Lieberman, Frank S; Buatti, John M; Mountz, James M; Erickson, Bradley J; Fennessy, Fiona M M; Huang, Wei; Kalpathy-Cramer, Jayashree; Wahl, Richard L; Linden, Hannah M; Kinahan, Paul E; Zhao, Binsheng; Hylton, Nola M; Gillies, Robert J; Clarke, Laurence; Nordstrom, Robert; Rubin, Daniel L

    2016-01-15

    As anticancer therapies designed to target specific molecular pathways have been developed, it has become critical to develop methods to assess the response induced by such agents. Although traditional, anatomic CT, and MRI examinations are useful in many settings, increasing evidence suggests that these methods cannot answer the fundamental biologic and physiologic questions essential for assessment and, eventually, prediction of treatment response in the clinical trial setting, especially in the critical period soon after treatment is initiated. To optimally apply advances in quantitative imaging methods to trials of targeted cancer therapy, new infrastructure improvements are needed that incorporate these emerging techniques into the settings where they are most likely to have impact. In this review, we first elucidate the needs for therapeutic response assessment in the era of molecularly targeted therapy and describe how quantitative imaging can most effectively provide scientifically and clinically relevant data. We then describe the tools and methods required to apply quantitative imaging and provide concrete examples of work making these advances practically available for routine application in clinical trials. We conclude by proposing strategies to surmount barriers to wider incorporation of these quantitative imaging methods into clinical trials and, eventually, clinical practice. Our goal is to encourage and guide the oncology community to deploy standardized quantitative imaging techniques in clinical trials to further personalize care for cancer patients and to provide a more efficient path for the development of improved targeted therapies.

  12. Quantitative label-free sperm imaging by means of transport of intensity

    Science.gov (United States)

    Poola, Praveen Kumar; Pandiyan, Vimal Prabhu; Jayaraman, Varshini; John, Renu

    2016-03-01

    Most living cells are optically transparent which makes it difficult to visualize them under bright field microscopy. Use of contrast agents or markers and staining procedures are often followed to observe these cells. However, most of these staining agents are toxic and not applicable for live cell imaging. In the last decade, quantitative phase imaging has become an indispensable tool for morphological characterization of the phase objects without any markers. In this paper, we report noninterferometric quantitative phase imaging of live sperm cells by solving transport of intensity equations with recorded intensity measurements along optical axis on a commercial bright field microscope.

  13. A study of the 42CrMo4 steel surface by quantitative XPS electron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Flori, M. [' Politehnica' University of Timisoara, Faculty of Engineering of Hunedoara, Str. Revolutiei, No. 5, 331128 Hunedoara (Romania)], E-mail: flori.mihaela@fih.upt.ro; Gruzza, B.; Bideux, L.; Monier, G.; Robert-Goumet, C. [LASMEA, UMR CNRS 6602, Blaise Pascal University, 63177 Aubiere Cedex (France)

    2008-05-30

    Quantitative X-ray photoelectron spectroscopy was used to characterize the native oxide film formed on 42CrMo4 steel surface by air exposure in normal conditions. In order to determine the thickness and composition of the oxide layer we have used a stacking layer model together with experimental XPS sputtering depth profiling. At a nanoscale study, to obtain quantitative results one must take into account fundamental parameters like the attenuation depth of photoelectrons. We have found that both lepidocrocit ({gamma}-FeOOH) and magnetite (Fe{sub 3}O{sub 4}) were present and the total thickness of the oxide layer was 16 monolayers.

  14. A study of the 42CrMo4 steel surface by quantitative XPS electron spectroscopy

    Science.gov (United States)

    Flori, M.; Gruzza, B.; Bideux, L.; Monier, G.; Robert-Goumet, C.

    2008-05-01

    Quantitative X-ray photoelectron spectroscopy was used to characterize the native oxide film formed on 42CrMo4 steel surface by air exposure in normal conditions. In order to determine the thickness and composition of the oxide layer we have used a stacking layer model together with experimental XPS sputtering depth profiling. At a nanoscale study, to obtain quantitative results one must take into account fundamental parameters like the attenuation depth of photoelectrons. We have found that both lepidocrocit (γ-FeOOH) and magnetite (Fe 3O 4) were present and the total thickness of the oxide layer was 16 monolayers.

  15. Will Quantitative Proteomics Redefine Some of the Key Concepts in Skeletal Muscle Physiology?

    Directory of Open Access Journals (Sweden)

    Agnieszka Gizak

    2016-01-01

    Full Text Available Molecular and cellular biology methodology is traditionally based on the reasoning called “the mechanistic explanation”. In practice, this means identifying and selecting correlations between biological processes which result from our manipulation of a biological system. In theory, a successful application of this approach requires precise knowledge about all parameters of a studied system. However, in practice, due to the systems’ complexity, this requirement is rarely, if ever, accomplished. Typically, it is limited to a quantitative or semi-quantitative measurements of selected parameters (e.g., concentrations of some metabolites, and a qualitative or semi-quantitative description of expression/post-translational modifications changes within selected proteins. A quantitative proteomics approach gives a possibility of quantitative characterization of the entire proteome of a biological system, in the context of the titer of proteins as well as their post-translational modifications. This enables not only more accurate testing of novel hypotheses but also provides tools that can be used to verify some of the most fundamental dogmas of modern biology. In this short review, we discuss some of the consequences of using quantitative proteomics to verify several key concepts in skeletal muscle physiology.

  16. Quantitative blood group typing using surface plasmon resonance.

    Science.gov (United States)

    Then, Whui Lyn; Aguilar, Marie-Isabel; Garnier, Gil

    2015-11-15

    The accurate and reliable typing of blood groups is essential prior to blood transfusion. While current blood typing methods are well established, results are subjective and heavily reliant on analysis by trained personnel. Techniques for quantifying blood group antibody-antigen interactions are also very limited. Many biosensing systems rely on surface plasmon resonance (SPR) detection to quantify biomolecular interactions. While SPR has been widely used for characterizing antibody-antigen interactions, measuring antibody interactions with whole cells is significantly less common. Previous studies utilized SPR for blood group antigen detection, however, showed poor regeneration causing loss of functionality after a single use. In this study, a fully regenerable, multi-functional platform for quantitative blood group typing via SPR detection is achieved by immobilizing anti-human IgG antibody to the sensor surface, which binds to the Fc region of human IgG antibodies. The surface becomes an interchangeable platform capable of quantifying the blood group interactions between red blood cells (RBCs) and IgG antibodies. As with indirect antiglobulin tests (IAT), which use IgG antibodies for detection, IgG antibodies are initially incubated with RBCs. This facilitates binding to the immobilized monolayer and allows for quantitative blood group detection. Using the D-antigen as an example, a clear distinction between positive (>500 RU) and negative (anti-D IgG. Complete regeneration of the anti-human IgG surface is also successful, showing negligible degradation of the surface after more than 100 regenerations. This novel approach is validated with human-sourced whole blood samples to demonstrate an interesting alternative for quantitative blood grouping using SPR analysis. PMID:26047997

  17. Use of "one-pot, mix-and-read" peptide-MHC class I tetramers and predictive algorithms to improve detection of cytotoxic T lymphocyte responses in cattle

    DEFF Research Database (Denmark)

    Svitek, Nicholas; Hansen, Andreas Martin; Steinaa, Lucilla;

    2014-01-01

    LA) and recombinant bovine beta 2-microglobulin from which p-MHC class I tetramers can be derived in similar to 48 h. We validated a set of p-MHC class I tetramers against a panel of CTL lines specific to seven epitopes on five different antigens of Theileria parva, a protozoan pathogen causing the lethal bovine...

  18. A novel proteomic biomarker panel as a diagnostic tool for patients with ovarian cancer

    DEFF Research Database (Denmark)

    Høgdall, Claus; Fung, Eric T; Christensen, Ib J;

    2011-01-01

    Previous reports have shown that the proteomic markers apolipoprotein A1, hepcidin, transferrin, inter-alpha trypsin IV internal fragment, transthyretin, connective-tissue activating protein 3 and beta-2 microglobulin may discriminate between a benign pelvic mass and ovarian cancer (OC). The aim ...

  19. Renal effects of acute exposure to toluene. A controlled clinical trial

    DEFF Research Database (Denmark)

    Nielsen, H K; Krusell, Lars Romer; Bælum, Jesper;

    1985-01-01

    Urinary excretion rates of beta 2-microglobulin and albumin were measured in 43 male printing trade workers and 43 age-matched male controls before and during exposure to toluene, 382 mg/m3, for 6 1/2 hours in a climate chamber. There were no significant changes in renal excretion rates of albumin...

  20. Changes in glomerular filtration rate, lithium clearance and plasma protein clearances in the early phase after unilateral nephrectomy in living healthy renal transplant donors

    DEFF Research Database (Denmark)

    Strandgaard, S; Kamper, A; Skaarup, P;

    1988-01-01

    1. Glomerular and tubular function was studied before and 2 months after unilateral nephrectomy in 14 healthy kidney donors by measurement of the clearances of 51Cr-labelled ethylenediaminetetra-acetate, lithium, beta 2-microglobulin, albumin and immunoglobulin G. 2. The glomerular filtration rate...