Comparison of the Roche Cobas(®) 4800 HPV assay to Digene Hybrid Capture 2, Roche Linear Array and Roche Amplicor for Detection of High-Risk Human Papillomavirus Genotypes in Women undergoing treatment for cervical dysplasia.

PubMed

Phillips, Samuel; Garland, Suzanne M; Tan, Jeffery H; Quinn, Michael A; Tabrizi, Sepehr N

2015-01-01

The recently FDA (U.S. food and drug administration) approved Roche Cobas(®) 4800 (Cobas) human papillomavirus (HPV) has limited performance data compared to current HPV detection methods for test of cure in women undergoing treatment for high grade lesions. Evaluation of Cobas HPV assay using historical samples from women undergoing treatment for cervical dysplasia. A selection of 407 samples was tested on the Cobas assay and compared to previous results from Hybrid Capture 2, HPV Amplicor and Roche Linear Array. Overall, a correlation between high-risk HPV positivity and high grade histological diagnosis was 90.6% by the Cobas, 86.1% by Hybrid Capture 2, 92.9% by HPV Amplicor and 91.8% by Roche Linear Array. The Cobas HPV assay is comparative to both the HPV Amplicor and Roche Linear Array assays and better than Hybrid capture 2 assay in the detection of High-Risk HPV in women undergoing treatment for cervical dysplasia. Copyright © 2014 Elsevier B.V. All rights reserved.

Equilibrium configurations of perfect fluid orbiting Schwarzschild-de Sitter black holes

NASA Astrophysics Data System (ADS)

Stuchlík, Z.; Slaný, P.; Hledík, S.

2000-11-01

The hydrodynamical structure of perfect fluid orbiting Schwarzschild-de Sitter black holes is investigated for configurations with uniform distribution of angular momentum density. It is shown that in the black-hole backgrounds admitting the existence of stable circular geodesics, closed equipotential surfaces with a cusp, allowing the existence of toroidal accretion disks, can exist. Two surfaces with a cusp exist for the angular momentum density smaller than the one corresponding to marginally bound circular geodesics; the equipotential surface corresponding to the marginally bound circular orbit has just two cusps. The outer cusp is located nearby the static radius where the gravitational attraction is compensated by the cosmological repulsion. Therefore, due to the presence of a repulsive cosmological constant, the outflow from thick accretion disks can be driven by the same mechanism as the accretion onto the black hole. Moreover, properties of open equipotential surfaces in vicinity of the axis of rotation suggest a strong collimation effects of the repulsive cosmological constant acting on jets produced by the accretion disks.

The Potential and Equipotentiality of Spacecraft

NASA Astrophysics Data System (ADS)

Afonin, V. V.

2004-01-01

The problem of maintenance of the equipotentiality of spacecraft surfaces is considered. The method under examination is the use of the ``conductive thermal-vacuum multilayer blanket'' (CMLB), whose outer surface represents a fabric woven of threads of glass fiber type with interwoven metal threads. The process of spacecraft potential formation and methods of the potential calculation are described, and the results of such a calculation for the illuminated and shadowed parts of spacecraft surfaces in some characteristic near-Earth plasma environments are presented. The CMLB model is described, and the potential distribution near the CMLB surface is calculated. The conclusion was drawn that the conductive thermal-vacuum multilayer blanket used in some cases on Russian spacecraft does not ensure the equipotentiality of spacecraft surfaces, and in the case of using CMLB, the differential spacecraft charging in outer regions of the Earth's magnetosphere may reach a dangerous level for onboard electronic systems. In spite of the fact that CMLB guards against large-scale powerful discharges, one cannot exclude discharges completely, what may result in broadband noise enhancement and cause onboard systems failures.

Equipotential doming in flooded circular basins on the moon

NASA Technical Reports Server (NTRS)

Roth, L. E.; Elachi, C.; Phillips, R. J.

1977-01-01

A procedure is presented that permits determination of the shape of the gravity field due to an arbitrary mass configuration with circular symmetry. The procedure is used to model the shape of the field associated with the lunar circular basins. The mean slopes of the equipotential surfaces generated by a superisostatic deposit corresponding to a near-surface Crisium-size mascon are calculated to fall within the range from 1:700 to 1:1000; those generated by a mantle rebound of the same excess mass, at 60 km below the lunar surface, cluster around the value of 1:1500.

Estimates of dispersive effects in a bent NLC Main Linac

DOE Office of Scientific and Technical Information (OSTI.GOV)

Michael Syphers and Leo Michelotti

2000-10-31

An alternative being considered for the Next Linear Collider (NLC) is not to tunnel in a straight line but to bend the Main Linac into an arc so as to follow a gravitational equipotential. The authors begin here an examination of the effects that this would have on vertical dispersion, with its attendant consequences on synchrotron radiation and emittance growth by looking at two scenarios: a gentle continuous bending of the beam to follow an equipotential surface, and an introduction of sharp bends at a few sites in the linac so as to reduce the maximum sagitta produced.

Comparative evaluation of neonatal bilirubin using Radiometer whole blood co-oximetry and plasma bilirubin methods from Roche Diagnostics and Ortho Clinical Diagnostics.

PubMed

Lano, Ian Marie; Lyon, Andrew W; Wang, Li; Ruskin, Rob; Lyon, Martha E

2018-03-01

Clinically significant variation has been reported within and between plasma and whole blood total bilirubin methods used to identify neonates for whom clinical intervention for hyperbilirubinemia may be required. To evaluate total bilirubin measurements between the Radiometer whole blood co-oximeter and plasma bilirubin methods from Roche Diagnostics and Ortho Clinical Diagnostics using neonatal specimens. Total bilirubin levels were analyzed by whole blood co-oximetry (Radiometer® ABL90). Specimens were centrifuged and plasma analyzed for total bilirubin with a diazo method (Roche Cobas® C-601) and a reflectance spectrophotometric BuBc dry film method (Ortho Clinical Diagnostics VITROS® 350). Results were evaluated by regression, Bland-Altman comparisons and t-tests. The patient correlation study yielded the following regression equations in μmol/L: a) Radiometer=1.03 Roche - 3.5μmol/L b) Radiometer=0.98 Ortho - 5.7μmol/L c) Roche=0.97 Ortho - 2.4μmol/L. The mean bias over the range of total bilirubin levels examined was -1.0μmol/L for the Radiometer versus the Roche (p≤0.305); -4.4μmol/L for the Radiometer versus Ortho (p≤0.005) and -4.4μmol/L for the Roche versus Ortho (p≤0.002). Whole blood total bilirubin measurement using the Radiometer ABL90 blood gas analyzer provides accurate and precise results compared to the Roche plasma diazo method. Compared to the reflectance spectrophotometric method, results are precise and had a small but statistically significant bias of -4.4μmol/L. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Transference of CALIPER pediatric reference intervals to biochemical assays on the Roche cobas 6000 and the Roche Modular P.

PubMed

Higgins, Victoria; Chan, Man Khun; Nieuwesteeg, Michelle; Hoffman, Barry R; Bromberg, Irvin L; Gornall, Doug; Randell, Edward; Adeli, Khosrow

2016-01-01

The Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER) has recently established pediatric age- and sex-specific reference intervals for over 85 biochemical markers on the Abbott Architect system. Previously, CALIPER reference intervals for several biochemical markers were successfully transferred from Abbott assays to Roche, Beckman, Ortho, and Siemens assays. This study further broadens the CALIPER database by performing transference and verification for 52 biochemical assays on the Roche cobas 6000 and the Roche Modular P. Using CLSI C28-A3 and EP9-A2 guidelines, transference of the CALIPER reference intervals was attempted for 16 assays on the Roche cobas 6000 and 36 on the Modular P. Calculated reference intervals were further verified using 100 healthy CALIPER samples. Most assays showed strong correlation between assay systems and were transferable from Abbott to the Roche cobas 6000 (81%) and the Modular P (86%). Bicarbonate and magnesium were not transferable on either system and calcium and prealbumin were not transferable to the Modular P. Of the transferable analytes, 62% and 61% were verified on the cobas 6000 and the Modular P, respectively. This study extends the utility of the CALIPER database to two additional analytical systems, which facilitates the broad application of CALIPER reference intervals at pediatric centers utilizing Roche biochemical assays. Transference studies across different analytical platforms can later be collectively analyzed in an attempt to develop common reference intervals across all clinical chemistry instruments to harmonize laboratory test interpretation in diagnosis and monitoring of pediatric disease. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Comparison of the Roche Cobas® 4800 HPV assay to Roche Amplicor for detection of high-risk human papillomavirus.

PubMed

Phillips, S; Cornall, A M; Machalek, D A; Garland, S M; Bateson, D; Garefalakis, M; Tabrizi, S N

2016-08-01

Roche Amplicor HPV (AMP) had previously been used for detection of high-risk human papillomavirus (HR-HPV) in epidemiological and clinical studies. As this assay is no longer available, we compared its performance using PreservCyt samples from women aged of 18-24 years attending for routine cervical cytology screening to Roche Cobas® 4800 (Cobas) to determine if subsequent studies could continue using the Cobas assay. Overall 507 samples were tested on Cobas and compared to previous AMP results, with discrepant samples tested on Roche Linear Array. Overall, agreement between the Cobas and AMP for the presence of HR HPV types was very high (κ = 0.81) (95 % CI: 0.76 - 0.87) with percentage agreement of 91.57 %. Cobas is comparable to AMP for the detection of HR-HPV types in a community recruited cohort of healthy women.

Comparison of clinical performances among Roche Cobas HPV, RFMP HPV PapilloTyper and Hybrid Capture 2 assays for detection of high-risk types of human papillomavirus.

PubMed

Yu, Shinae; Kwon, Min-Jung; Lee, Eun Hee; Park, Hyosoon; Woo, Hee-Yeon

2015-09-01

The cervical cancer screening guidelines suggest that early detection of HPV16 and HPV18 is helpful for identifying women with cervical intraepithelial neoplasia (CIN) grade two or higher. We comparatively evaluated three HPV DNA assays, Roche Cobas HPV, RFMP HPV PapilloTyper, and Hybrid Capture 2 (HC2). A total of 861 cervical swab samples from women over 30 years of age were classified into two groups, that is, high grade squamous intraepithelial lesion (HSIL) and non-HSIL, according to cervical cytology results and analyzed by three assays. The results of direct sequencing or Linear array HPV genotyping test were considered true when the three assays presented discrepancies. The concordance rates between Roche Cobas HPV versus RFMP HPV PapilloTyper, RFMP HPV PapilloTyper versus HC2, and Roche Cobas versus HC2 were 94.5%, 94.3%, and 95.9%, respectively. For detection of HPV16 and HPV18, Roche Cobas HPV showed the concordance rates of 98.3% (κ = 0.73) and 99.4% (κ = 0.40) with the confirmation tests, respectively; and RFMP HPV PapilloTyper showed the concordance rates of 99.5% (κ = 0.92) and 100.0% (κ = 1.00), respectively. In conclusion, Roche Cobas HPV, RFMP HPV PapilloTyper, and HC2 showed high agreement rates. Roche Cobas HPV and RFMP HPV PapilloTyper are particularly useful, since both provide HPV specific genotypes, HPV16 and HPV18. © 2015 Wiley Periodicals, Inc.

Comparison of DRY and WET vaginal swabs with cervical specimens in Roche Cobas 4800 HPV and Abbott RealTime High Risk HPV tests.

PubMed

Jun, Jae Kwan; Lim, Myong Cheol; Hwang, Sang-Hyun; Shin, Hye Young; Hwang, Na Rae; Kim, Yeon-Jin; Yoo, Chong Woo; Lee, Dong Ock; Joo, Jungnam; Park, Sang-Yoon; Lee, Do-Hoon

2016-06-01

Self-collected vaginal swab samples have been proposed as an alternative specimen collection method for human papillomavirus (HPV) DNA detection. Two vaginal swabs (a cone-shaped flocked swab (DRY) and a L-shape FLOQSwab with 2mL eNAT transport medium (WET)) were compared to standard cervical samples for HPV DNA testing. Additionally, they were also compared by using Roche Cobas 4800 HPV (Roche_HPV) and Abbott Real-time High Risk HPV (Abbott_HPV) tests. Ninety-six women were prospectively enrolled from the National Cancer Center in Korea between June and August 2015. WET and DRY vaginal swabs and cervical specimens were collected. Roche_HPV and Abbott_HPV tests were performed. The Roche_HPV test on cervical specimens was used as reference. The observed agreements (kappa) of Roche_HPV and Abbott_HPV between WET and DRY swabs were 89.6% (0.790, 95% confidence interval (95% CI): 0.667-0.913) and 91.7% (0.833, 95%CI: 0.723-0.943), respectively. No statistical difference was observed between WET and DRY swabs (p>0.05 for all comparisons). For HPV16/18, the sensitivity/specificity of Roche_HPV on the DRY and WET samples presented 93.8%/96.3% and 87.5%/97.5%, respectively. For other High Risk HPV (hrHPV), the sensitivity/specificity of Roche_HPV on the DRY and WET swabs presented 91.9%/91.5% and 97.3%/98.3, respectively. The sensitivity/specificity of the Abbott_HPV on the DRY and WET swabs were 93.8%/98.8%, 87.5%/98.8% for HPV16/18, and 91.9%/93.2%, 100.0%/93.2% for other hrHPV, respectively. HPV tests performed similarly when using vaginal DRY and WET swab samples. Using DRY and WET swabs to collect vaginal specimens could be an alternative to collecting cervical samples for HPV DNA testing. Copyright © 2016 Elsevier B.V. All rights reserved.

Multilaboratory comparison of hepatitis C virus viral load assays.

PubMed

Caliendo, A M; Valsamakis, A; Zhou, Y; Yen-Lieberman, B; Andersen, J; Young, S; Ferreira-Gonzalez, A; Tsongalis, G J; Pyles, R; Bremer, J W; Lurain, N S

2006-05-01

We report a multilaboratory evaluation of hepatitis C virus (HCV) viral load assays to determine their linear range, reproducibility, subtype detection, and agreement. A panel of HCV RNA samples ranging in nominal concentration from 1.0 to 7.0 log10 IU/ml was constructed by diluting a clinical specimen (genotype 1b). Replicates of the panel were tested in multiple laboratories using the Abbott TaqMan analyte-specific reagent (Abbott reverse transcription-PCR [RT-PCR]), Roche TaqMan RUO (Roche RT-PCR), Roche Amplicor Monitor HCV 2.0 (Roche Monitor), and Bayer VERSANT HCV RNA 3.0 (Bayer bDNA) assays. Bayer bDNA-negative specimens were tested reflexively using the Bayer VERSANT HCV RNA qualitative assay (Bayer TMA). Abbott RT-PCR and Roche RT-PCR detected all 28 replicates with a concentration of 1.0 log10 IU/ml and were linear to 7.0 log10 IU/ml. Roche Monitor and Bayer bDNA detected 27 out of 28 and 13 out of 28 replicates, respectively, of 3.0 log10 IU/ml. Bayer TMA detected all seven replicates with 1.0 log10 IU/ml. Bayer bDNA was the most reproducible of the four assays. The mean viral load values for panel members in the linear ranges of the assays were within 0.5 log10 for the different tests. Eighty-nine clinical specimens of various genotypes (1 through 4) were tested in the Bayer bDNA, Abbott RT-PCR, and Roche RT-PCR assays. For Abbott RT-PCR, mean viral load values were 0.61 to 0.96 log10 greater than the values for Bayer bDNA assay for samples with genotype 1, 2, or 3 samples and 0.08 log10 greater for genotype 4 specimens. The Roche RT-PCR assay gave mean viral load values that were 0.28 to 0.82 log10 greater than those obtained with the Bayer bDNA assay for genotype 1, 2, and 3 samples. However, for genotype 4 samples the mean viral load value obtained with the Roche RT-PCR assay was, on average, 0.15 log10 lower than that of the Bayer bDNA. Based on these data, we conclude that the sensitivity and linear range of the Abbott and Roche RT-PCR assays enable them to be used for HCV diagnostics and therapeutic monitoring. However, the differences in the viral load values obtained with the different assays underscore the importance of using one assay when monitoring response to therapy.

On the origin of X-ray variability of SS 433

NASA Astrophysics Data System (ADS)

Band, D. L.; Grindlay, J. E.

1984-10-01

The X-ray flares observed from the central source in SS 433 by the Einstein telescope are attributed to surges in the mass transfer rate due to changes in the critical Roche volume of the companion. Analysis of the Roche potential for a primary with spin misaligned with the orbital axis, as required by the slaved disk model, predicts that the critical Roche volume will contract twice per orbit if the orbit is circular. A critical Roche volume fractional change of 1-2 percent is found by applying this potential to SS 433. The nutation of the companion should not affect the steady precession of its spin. Aspects of this work strengthen the evidence that the compact object might be a black hole.

Comparison of the Abbott RealTime High Risk HPV test and the Roche cobas 4800 HPV test using urine samples.

PubMed

Lim, Myong Cheol; Lee, Do-Hoon; Hwang, Sang-Hyun; Hwang, Na Rae; Lee, Bomyee; Shin, Hye Young; Jun, Jae Kwan; Yoo, Chong Woo; Lee, Dong Ock; Seo, Sang-Soo; Park, Sang-Yoon; Joo, Jungnam

2017-05-01

Human papillomavirus (HPV) testing based on cervical samples is important for use in cervical cancer screening. However, cervical sampling is invasive. Therefore, non-invasive methods for detecting HPV, such as urine samples, are needed. For HPV detection in urine samples, two real-time PCR (RQ-PCR) tests, Roche cobas 4800 test (Roche_HPV; Roche Molecular Diagnostics) and Abbott RealTime High Risk HPV test (Abbott_HPV; Abbott Laboratories) were compared to standard cervical samples. The performance of Roche_HPV and Abbott_HPV for HPV detection was evaluated at the National Cancer Center using 100 paired cervical and urine samples. The tests were also compared using urine samples stored at various temperatures and for a range of durations. The overall agreement between the Roche_HPV and Abbott_HPV tests using urine samples for any hrHPV type was substantial (86.0% with a kappa value of 0.7173), and that for HPV 16/18 was nearly perfect (99.0% with a kappa value of 0.9668). The relative sensitivities (based on cervical samples) for HPV 16/18 detection using Roche_HPV and Abbott_HPV with urine samples were 79.2% (95% CI; 57.9-92.9%) and 81.8% (95% CI; 59.7-94.8%), respectively. When the cut-off C T value for Abbott_HPV was extended to 40 for urine samples, the relative sensitivity of Abbott_HPV increased to 91.7% from 81.8% for HPV16/18 detection and to 87.0% from 68.5% for other hrHPV detection. The specificity was not affected by the change in the C T threshold. Roche_HPV and Abbott_HPV showed high concordance. However, HPV DNA detection using urine samples was inferior to HPV DNA detection using cervical samples. Interestingly, when the cut-off C T value was set to 40, Abbott_HPV using urine samples showed high sensitivity and specificity, comparable to those obtained using cervical samples. Fully automated DNA extraction and detection systems, such as Roche_HPV and Abbott_HPV, could reduce the variability in HPV detection and accelerate the standardization of HPV detection in urine. Thus, urine samples may be an effective alternative for HPV detection in women who hesitate to participate in cervical cancer screening programs. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison between Roche and Xpert in HIV-1 RNA quantitation: A high concordance between the two techniques except for a CRF02_AG subtype variant with high viral load titters detected by Roche but undetected by Xpert.

PubMed

Avidor, Boaz; Matus, Natalia; Girshengorn, Shirley; Achsanov, Svetlana; Gielman, Simona; Zeldis, Irene; Schweitzer, Inbal; Adler, Amos; Turner, Dan

2017-08-01

HIV-1 viral load (VL) testing is important to predict viral progression and to monitor the response to antiretroviral therapy. New HIV-1 VL tests are continuously introduced to the market. Their performance is usually compared to Abbott and/or Roche HIV-1 VL assays, as reference. The Xpert HIV-1 VL test was recently introduced, but its performance compared to Roche has not been sufficiently studied. To compare the Xpert assay with Roche and to assess its use in the HIV clinical laboratory. A total of 383 plasma samples of HIV-1 infected patients previously tested by Roche, were retrospectively tested by Xpert to determine concordance between the two assays. Samples included a diversity of HIV-1 subtypes and a wide range of VLs. There was a high concordance between the two assays, except for a CRF02_AG subtype variant with high VL titters, that was detected by Roche but undetected by Xpert. The 5' long terminal repeat gene region of this virus, targeted by the Xpert assay, was amplified and sequenced. A 25 nucleotide insert was identified, but was unmatched to any known sequences of HIV-1. This particular insert, however could not explain the false-negativity by the Xpert assay. This study underlines the challenge to routine VL testing due to the high genetic diversity of HIV-1. Clinicians should, therefore be advised that a negative VL in cases where the clinical picture does not match the laboratory report, might in fact be, a false-negative result of the VL assay. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of the Gen-Probe Aptima HIV-1 and Abbott HIV-1 qualitative assays with the Roche Amplicor HIV-1 DNA assay for early infant diagnosis using dried blood spots.

PubMed

Nelson, Julie A E; Hawkins, J Tyler; Schanz, Maria; Mollan, Katie; Miller, Melissa B; Schmitz, John L; Fiscus, Susan A

2014-08-01

The current gold standard for infant diagnosis of HIV-1 is the Roche Amplicor Qualitative DNA assay, but it is being phased out. Compare the Abbott qualitative assay and the Gen-Probe Aptima assay to the gold standard Roche DNA assay using dried blood spots (DBS). The Gen-Probe Aptima and Abbott qualitative HIV-1 assays were compared to the Roche DNA assay for early infant diagnosis. Specificity and sensitivity were determined for the three assays using DBS from 50 HIV-exposed uninfected infants and 269 HIV-1 infected adults from North Carolina, respectively. All of the negative and 151 of the positive DBS had valid results on the 3 different assays, and an additional 118 positive DBS had valid results on the Roche DNA and Aptima assays. All three assays were very specific. The Roche DNA assay was the most sensitive (96.7%) over a wide range of HIV PVL, including samples with PVL<400 copies/ml. Restricted to samples with PVL>400 copies/ml, the Gen-Probe Aptima assay had sensitivity (96.5%) comparable to the Roche DNA assay (98.8%). The Abbott Qualitative assay was the least sensitive and only had sensitivity above 95% among samples with PVL over 1000 copies/ml. The Abbott HIV-1 Qualitative assay was not as sensitive as the comparator assays, so it would not be a useful replacement assay, especially for infants taking antiretroviral prophylaxis. The Gen-Probe Aptima assay is an adequate replacement option for infant diagnosis using DBS. Copyright © 2014 Elsevier B.V. All rights reserved.

Intramolecular Oxidative O-Demethylation of an Oxoferryl Porphyrin Complexed with a Per-O-methylated β-Cyclodextrin Dimer.

PubMed

Kitagishi, Hiroaki; Kurosawa, Shun; Kano, Koji

2016-11-22

The intramolecular oxidation of ROCH 3 to ROCH 2 OH, where the latter compound spontaneously decomposed to ROH and HCHO, was observed during the reaction of the supramolecular complex (met-hemoCD3) with cumene hydroperoxide in aqueous solution. Met-hemoCD3 is composed of meso-tetrakis(4-sulfonatophenyl)porphinatoiron(III) (Fe III TPPS) and a per-O-methylated β-cyclodextrin dimer having an -OCH 2 PyCH 2 O- linker (Py=pyridine-3,5-diyl). The O=Fe IV TPPS complex was formed by the reaction of met-hemoCD3 with cumene hydroperoxide, and isolated by gel-filtration chromatography. Although the isolated O=Fe IV TPPS complex in the cyclodextrin cage was stable in aqueous solution at 25 °C, it was gradually converted to Fe II TPPS (t 1/2 =7.6 h). This conversion was accompanied by oxidative O-demethylation of an OCH 3 group in the cyclodextrin dimer. The results indicated that hydrogen abstraction by O=Fe IV TPPS from ROCH 3 yields HO-Fe III TPPS and ROCH 2 . . This was followed by radical coupling to afford Fe II TPPS and ROCH 2 OH. The hemiacetal (ROCH 2 OH) immediately decomposed to ROH and HCHO. This study revealed the ability of oxoferryl porphyrin to induce two-electron oxidation. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wallace, Joshua; Tremaine, Scott; Chambers, John, E-mail: joshuajw@princeton.edu

Collisional fragmentation is shown to not be a barrier to rocky planet formation at small distances from the host star. Simple analytic arguments demonstrate that rocky planet formation via collisions of homogeneous gravity-dominated bodies is possible down to distances of order the Roche radius ( r {sub Roche}). Extensive N -body simulations with initial bodies ≳1700 km that include plausible models for fragmentation and merging of gravity-dominated bodies confirm this conclusion and demonstrate that rocky planet formation is possible down to ∼1.1 r {sub Roche}. At smaller distances, tidal effects cause collisions to be too fragmenting to allow mass buildupmore » to a final, dynamically stable planetary system. We argue that even differentiated bodies can accumulate to form planets at distances that are not much larger than r {sub Roche}.« less

New patterns in dust off the edge of Saturn’s main rings

NASA Astrophysics Data System (ADS)

Chancia, Robert Ormal; Hedman, Matthew M.; Ye, Shengyi; Kurth, William S.

2017-10-01

The Roche Division is a 3000-km-span of diffuse dust located at the outer edge of Saturn’s main ring system between the A and F rings. Several high-resolution images from Cassini’s orbit insertion revealed two regions with higher concentrations of dust within the Roche Division. These proposed dusty ringlets R/2004 S1 (radius=137,630 km) and R/2004 S2 (radius=138,900 km) lie coincident with the orbit of Atlas and slightly interior to the orbit of Prometheus respectively (Porco et al. 2005a Science). Using several image sequences later obtained by Cassini Hedman et al. 2009 (Icarus) found that these concentrations of dusty ring material are not simple ringlets, but are in fact organized into canted azimuthal brightness variations with a periodicity akin to a 3:4 resonance with Saturn’s rotation rate. The presumed perturbing phenomenon is Saturn’s kilometric radiation (SKR), a strong low wavelength component of the planet’s radio emissions, whose power oscillates near the planet’s rotation rate at a frequency matching the Roche Division structures. However, over the course of the Cassini mission the SKR period has varied by at least 7 minutes. As a result, the location of the resonance moved interior to the edge of the A ring and out of the Roche Division around the time of Saturn’s equinox. Subsequent observations of the Roche Division in the this time period show no evidence of the prominent structures previously observed during the first few years of the Cassini mission. Recently, the 3:4 resonant structures have reappeared in the Roche Division as one of the SKR periods has increased. Here we show that the these dusty Roche Division structures are present in sync with the varying SKR period using images sequences spanning the entire Cassini mission. We also highlight some particularly optimal observations, obtained during Cassini’s F-ring proximal and grand finale orbits, which reveal the dusty structure of the Roche Division in unprecedented detail.

An Elliptic PDE Approach for Shape Characterization

PubMed Central

Haidar, Haissam; Bouix, Sylvain; Levitt, James; McCarley, Robert W.; Shenton, Martha E.; Soul, Janet S.

2009-01-01

This paper presents a novel approach to analyze the shape of anatomical structures. Our methodology is rooted in classical physics and in particular Poisson's equation, a fundamental partial differential equation [1]. The solution to this equation and more specifically its equipotential surfaces display properties that are useful for shape analysis. We present a numerical algorithm to calculate the length of streamlines formed by the gradient field of the solution to this equation for 2D and 3D objects. The length of the streamlines along the equipotential surfaces was used to build a new function which can characterize the shape of objects. We illustrate our method on 2D synthetic and natural shapes as well as 3D medical data. PMID:17271986

Utility of the Roche Cobas 4800 for detection of high-risk human papillomavirus in formalin-fixed paraffin-embedded oropharyngeal squamous cell carcinoma.

PubMed

Pettus, Jason R; Wilson, Terri L; Steinmetz, Heather B; Lefferts, Joel A; Tafe, Laura J

2017-02-01

Clinical laboratories are expected to reliably identify human papilloma virus (HPV) associated oropharyngeal squamous cell carcinoma (OPSCC) for prognostic and potential therapeutic applications. In addition to surrogate p16 immunohistochemistry (IHC) testing, DNA-based HPV-specific testing strategies are widely utilized. Recognizing the efficiency of the Roche Cobas 4800 platform for testing gynecological cytology specimens for high-risk HPV, we elected to evaluate the potential utility of this platform for testing formalin-fixed paraffin-embedded (FFPE) OPSCC tissue. Using the Roche Linear Array assay for comparison, we tested twenty-eight samples (16 primary OPSCC, 2 lymph node metastases from primary OPSCC, 1 oral tongue carcinoma, 3 benign squamous papillomas, and 3 non-oropharyngeal carcinoma tissues). Excluding two invalid results, the Roche Cobas 4800 testing resulted in excellent inter-assay concordance (25/26, 96.2%) and 100% concordance for HPV-16/HPV-18 positive samples. This data suggests that the Roche Cobas 4800 platform may be a cost-effective method for testing OPSCC FFPE tissues in a clinical molecular pathology laboratory setting. Copyright © 2016 Elsevier Inc. All rights reserved.

Calculations of the electrostatic potential adjacent to model phospholipid bilayers.

PubMed

Peitzsch, R M; Eisenberg, M; Sharp, K A; McLaughlin, S

1995-03-01

We used the nonlinear Poisson-Boltzmann equation to calculate electrostatic potentials in the aqueous phase adjacent to model phospholipid bilayers containing mixtures of zwitterionic lipids (phosphatidylcholine) and acidic lipids (phosphatidylserine or phosphatidylglycerol). The aqueous phase (relative permittivity, epsilon r = 80) contains 0.1 M monovalent salt. When the bilayers contain < 11% acidic lipid, the -25 mV equipotential surfaces are discrete domes centered over the negatively charged lipids and are approximately twice the value calculated using Debye-Hückel theory. When the bilayers contain > 25% acidic lipid, the -25 mV equipotential profiles are essentially flat and agree well with the values calculated using Gouy-Chapman theory. When the bilayers contain 100% acidic lipid, all of the equipotential surfaces are flat and agree with Gouy-Chapman predictions (including the -100 mV surface, which is located only 1 A from the outermost atoms). Even our model bilayers are not simple systems: the charge on each lipid is distributed over several atoms, these partial charges are non-coplanar, there is a 2 A ion-exclusion region (epsilon r = 80) adjacent to the polar headgroups, and the molecular surface is rough. We investigated the effect of these four factors using smooth (or bumpy) epsilon r = 2 slabs with embedded point charges: these factors had only minor effects on the potential in the aqueous phase.

Calculations of the electrostatic potential adjacent to model phospholipid bilayers.

PubMed Central

Peitzsch, R M; Eisenberg, M; Sharp, K A; McLaughlin, S

1995-01-01

We used the nonlinear Poisson-Boltzmann equation to calculate electrostatic potentials in the aqueous phase adjacent to model phospholipid bilayers containing mixtures of zwitterionic lipids (phosphatidylcholine) and acidic lipids (phosphatidylserine or phosphatidylglycerol). The aqueous phase (relative permittivity, epsilon r = 80) contains 0.1 M monovalent salt. When the bilayers contain < 11% acidic lipid, the -25 mV equipotential surfaces are discrete domes centered over the negatively charged lipids and are approximately twice the value calculated using Debye-Hückel theory. When the bilayers contain > 25% acidic lipid, the -25 mV equipotential profiles are essentially flat and agree well with the values calculated using Gouy-Chapman theory. When the bilayers contain 100% acidic lipid, all of the equipotential surfaces are flat and agree with Gouy-Chapman predictions (including the -100 mV surface, which is located only 1 A from the outermost atoms). Even our model bilayers are not simple systems: the charge on each lipid is distributed over several atoms, these partial charges are non-coplanar, there is a 2 A ion-exclusion region (epsilon r = 80) adjacent to the polar headgroups, and the molecular surface is rough. We investigated the effect of these four factors using smooth (or bumpy) epsilon r = 2 slabs with embedded point charges: these factors had only minor effects on the potential in the aqueous phase. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 PMID:7756540

Evaluation of a third party enzymatic ammonia method for use on the Roche Cobas 6000 (c501) automated platform.

PubMed

Seiden-Long, Isolde; Schnabl, Kareena; Skoropadyk, Wendy; Lennon, Nola; McKeage, Arlayne

2014-08-01

Adaptation of the Randox Enzymatic Manual UV Ammonia method to be used on the Roche Cobas 6000 (c501) automated analyzer platform. The Randox ammonia reagent was evaluated for precision, linearity, accuracy and interference from hemolysis, icterus and lipemia on the Roche c501 analyzer. Comparison studies were conducted for the Randox reagent between Roche c501, Siemens Vista, Ortho Vitros 250, and Beckman DxC methods. The Randox reagent demonstrates acceptable within-run (L1=65 μmol/L, CV 3.4% L2=168 μmol/L, CV 1.9%) and between-run precision (L1=29 μmol/L, CV 7.3% L2=102 μmol/L, CV 3.0%), Analytical Measurement Range (7-940 μmol/L), and accuracy. The method interference profile is superior for the Randox method (hemolysis index up to 600, icteric index up to 60, lipemic index up to 100) as compared to the Roche method (hemolysis index up to 200, icteric index up to 10, lipemic index up to 50). Comparison was very good between the Randox reagent and two other wet chemistry platforms. The Randox Enzymatic Manual UV Ammonia reagent is an available alternative to the Roche Cobas c501 reagent. The method is more robust to endogenous interferences and less prone to instrument error flags, thus allowing the majority of clinical specimens to be reported without additional sample handling at our institution. Copyright © 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Operational impact of using a vanadate oxidase method for direct bilirubin measurements at an academic medical center clinical laboratory.

PubMed

Dhungana, Neha; Morris, Cory; Krasowski, Matthew D

2017-08-01

The aim of this study was to compare the operational impact of using vanadate oxidase versus diazo direct bilirubin assays for an academic medical center patient population. Retrospective study was done over an approximately 3.5 year period. The main automated chemistry instrumentation was a Roche Diagnostics cobas 8000 line. The Roche Direct Bilirubin assay was compared to Diazyme Laboratories Direct Bilirubin Assay and Randox Laboratories Direct Bilirubin assay using manufacturer's guidelines for hemolysis index, lipemia index, and analytical measurement range (AMR). Retrospective data was analyzed for 47,333 serum/plasma specimens that had clinical orders for direct bilirubin. A total of 5943 specimens (12.6%) exceeded the hemolysis index limit for the Roche method compared to only 0.2% and 0.05% of specimens for the Diazyme and Randox methods, respectively. The impact was particularly large on patients less than 2 years old, for which 51.3% of specimens exceeded the hemolysis index for the Roche method. A total of 1671 specimens (3.5%) exceeded the lipemia index limit for the Roche method compared to less than 0.1% for the Randox method. Lastly, 988 (2.1%) of specimens had direct bilirubin concentrations exceeding the upper AMR limit of 10 mg/dL [171 µmol/L] for the Roche assay compared to less than 1% of specimens for the vanadate oxidase methods. Vanadate oxidase direct bilirubin methods offer advantages over diazo methods in terms of less interference by hemolysis and lipemia, as well as wider AMR. The advantages are particularly evident for neonatal and infant populations.

Semi-analytical model for a static sheath including a weakly collisional presheath

NASA Astrophysics Data System (ADS)

Shirafuji, Tatsuru; Denpoh, Kazuki

2018-06-01

A semi-analytical static sheath (SASS) model can provide a spatial potential profile on a biased surface with microstructures, which can be used for predicting ion trajectories on the surface. However, two- or three-dimensional SASS models require a search procedure for a sheath edge equipotential profile, at which ions have the Bohm velocity, as the starting positions for calculating ion trajectories. This procedure can be troublesome when surface microstructures have complex structures. This difficulty is due to the fact that the SASS model cannot handle a presheath region. In this work, we propose a modified SASS model that can handle a presheath region. By using the modified SASS model, ion trajectories can be calculated from edges with arbitrary geometry without searching for the equipotential profile corresponding to sheath edges.

Hazardous Waste Cleanup: DSM Nutritional Products Incorporated in Belvidere, New Jersey

EPA Pesticide Factsheets

DSM Nutritional Products, Inc., formerly Hoffman-LaRoche (Roche) Belvidere is located on Maunkachunk Road in White Township, New Jersey. The site occupies approximately 500 acres in Warren County. The facility has been manufacturing vitamins since 1961.

A comparison between two different automated total 25-hydroxyvitamin D immunoassay methods using liquid chromatography-tandem mass spectrometry.

PubMed

Kocak, Fatma Emel; Ozturk, Bahadir; Isiklar, Ozben Ozden; Genc, Ozlem; Unlu, Ali; Altuntas, Irfan

2015-01-01

Total 25-hydroxyvitamin D [25(OH)D] is the most reliable indicator of vitamin D status. In this study, we compared two automated immunoassay methods, the Abbott Architect 25-OH Vitamin D assay and the Roche Cobas Vitamin D total assay, with the liquid chromatography-tandem mass spectrometry (LC-MS/MS). One hundred venous blood samples were randomly selected from routine vitamin D tests. Two of the serum aliquots were analyzed at the Abbott Architect i2000 and the Roche Cobas 6000's module e601 in our laboratory within the same day. The other serum aliquots were analyzed at the LC-MS/MS in different laboratory. Passing-Bablok regression analysis and Bland-Altman plot were used to compare methods. Inter-rater agreement was analyzed using kappa (κ) analysis. The Roche assay showed acceptable agreement with the LC-MS/MS based on Passing-Bablok analysis (intercept: -5.23 nmol/L, 95% CI: -8.73 to 0.19; slope: 0.97, 95% CI: 0.77 to 1.15). The Abbott assay showed proportional (slope: 0.77, 95% CI: 0.67 to 0.85) and constant differences (intercept: 17.08 nmol/L; 95% CI: 12.98 to 21.39). A mean bias of 15.1% was observed for the Abbott and a mean bias of -14.1% was observed for the Roche based on the Bland-Altman plots. We found strong to nearly perfect agreement in vitamin D status between the immunoassays and LC-MS/MS. (κ: 0.83 for Abbott, κ: 0.93 for Roche) using kappa analysis. Both immunoassays demonstrated acceptable performance, but the Roche Cobas assay demonstrated better performance than the Abbott Architect in the studied samples.

Clinical evaluation of Roche COBAS® AmpliPrep/COBAS® TaqMan® CMV Test using non-plasma samples.

PubMed

Hildenbrand, Cynthia; Wedekind, Laura; Li, Ge; vonRentzell, Jeanne E; Shah, Krunal; Rooney, Paul; Harrington, Amanda T; Zhao, Richard Y

2018-05-24

Cytomegalovirus (CMV) infection is a leading cause of loss of hearing, vision, and mental retardation in congenitally infected children. It is also associated with complications of organ-transplant and opportunistic HIV co-infection. The Roche COBAS ® AmpliPrep/COBAS ® TaqMan ® CMV Test is a FDA-approved test that measures CMV DNA viral load in plasma for the diagnosis and management of patients at risk for CMV-associated diseases. Besides plasma, CMV is often found in bronchoalveolar lavage (BAL), cerebrospinal fluid (CSF) and urine. Thus, monitoring of CMV for critical care of patients in these non-plasma samples becomes necessary. The objective of this study was to conduct an analytic and clinical feasibility study of the Roche CMV Test in BAL, CSF, and urine. The lower limit of detection (LOD), analytic measurement range (AMR), assay sensitivity, specificity, and precision were determined. Results of this study showed the LODs were 50, 100 and 300 IU/mL for BAL, CSF, or urine, respectively. The AMRs were from log 10 2.48 to log 10 5.48. The assay specificity was 94.4% for BAL, and 100% for CSF and urine. The assay precision was all within the acceptable range. The performance of Roche test was further compared with two comparators including the RealTime CMV Assay (Abbott Molecular) and a CMV Quantitative PCR Test (Vela Diagnostics). There was a general positive correlation between the Roche method and the Abbott or the Vela method. Overall, this study suggests the Roche CMV Test is suitable for the quantification of CMV viral load DNA in the described non-plasma samples. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Multicenter evaluation of the new Abbott RealTime assays for quantitative detection of human immunodeficiency virus type 1 and hepatitis C virus RNA.

PubMed

Schutten, M; Peters, D; Back, N K T; Beld, M; Beuselinck, K; Foulongne, V; Geretti, A-M; Pandiani, L; Tiemann, C; Niesters, H G M

2007-06-01

The analytical performances of the new Abbott RealTime hepatitis C virus (HCV) and human immunodeficiency virus type 1 viral load assays were compared at nine laboratories with different competitor assays. These included the Abbott LcX, Bayer Versant bDNA, Roche COBAS Amplicor, and Roche COBAS TaqMan assays. Two different protocols used during the testing period with and without a pre-m1000 RNA isolation spin were compared. The difference proved to be nonsignificant. A uracil-N-glycosylase (UNG) contamination control option in the HCV test for previous Roche COBAS Amplicor users was evaluated. It proved to decrease amplicon carryover by 100-fold independent of the amplicon input concentration. The protocol including UNG proved to overcome problems with false-positive negative controls. Comparison with other assays revealed only minor differences. The largest difference was observed between the Abbott HCV RealTime assay and the Roche COBAS Amplicor HCV Monitor version 2.0 assay.

Electric Double-Layer Interaction between Dissimilar Charge-Conserved Conducting Plates.

PubMed

Chan, Derek Y C

2015-09-15

Small metallic particles used in forming nanostructured to impart novel optical, catalytic, or tribo-rheological can be modeled as conducting particles with equipotential surfaces that carry a net surface charge. The value of the surface potential will vary with the separation between interacting particles, and in the absence of charge-transfer or electrochemical reactions across the particle surface, the total charge of each particle must also remain constant. These two physical conditions require the electrostatic boundary condition for metallic nanoparticles to satisfy an equipotential whole-of-particle charge conservation constraint that has not been studied previously. This constraint gives rise to a global charge conserved constant potential boundary condition that results in multibody effects in the electric double-layer interaction that are either absent or are very small in the familiar constant potential or constant charge or surface electrochemical equilibrium condition.

Design and Development of an Equipotential Voltage Reference (Grounding) System for a Low-Cost Rapid-Development Modular Spacecraft Architecture

NASA Technical Reports Server (NTRS)

Lukash, James A.; Daley, Earl

2011-01-01

This work describes the design and development effort to adapt rapid-development space hardware by creating a ground system using solutions of low complexity, mass, & cost. The Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft is based on the modular common spacecraft bus architecture developed at NASA Ames Research Center. The challenge was building upon the existing modular common bus design and development work and improving the LADEE spacecraft design by adding an Equipotential Voltage Reference (EVeR) system, commonly referred to as a ground system. This would aid LADEE in meeting Electromagnetic Environmental Effects (E3) requirements, thereby making the spacecraft more compatible with itself and its space environment. The methods used to adapt existing hardware are presented, including provisions which may be used on future spacecraft.

Stress distribution and topography of Tellus Regio, Venus

NASA Technical Reports Server (NTRS)

Williams, David R.; Greeley, Ronald

1989-01-01

The Tellus Regio area of Venus represents a subset of a narrow latitude band where Pioneer Venus Orbiter (PVO) altimetry data, line-of-sight (LOS) gravity data, and Venera 15/16 radar images have all been obtained with good resolution. Tellus Regio also has a wide variety of surface morphologic features, elevations ranging up to 2.5 km, and a relatively low LOS gravity anomaly. This area was therefore chosen in order to examine the theoretical stress distributions resulting from various models of compensation of the observed topography. These surface stress distributions are then compared with the surface morphology revealed in the Venera 15/16 radar images. Conclusions drawn from these comparisons will enable constraints to be put on various tectonic parameters relevant to Tellus Regio. The stress distribution is calculated as a function of the topography, the equipotential anomaly, and the assumed model parameters. The topography data is obtained from the PVO altimetry. The equipotential anomaly is estimated from the PVO LOS gravity data. The PVO LOS gravity represents the spacecraft accelerations due to mass anomalies within the planet. These accelerations are measured at various altitudes and angles to the local vertical and therefore do not lend themselves to a straightforward conversion. A minimum variance estimator of the LOS gravity data is calculated, taking into account the various spacecraft altitudes and LOS angles and using the measured PVO topography as an a priori constraint. This results in an estimated equivalent surface mass distribution, from which the equipotential anomaly is determined.

Clinical performance of the LCx HCV RNA quantitative assay.

PubMed

Bertuzis, Rasa; Hardie, Alison; Hottentraeger, Barbara; Izopet, Jacques; Jilg, Wolfgang; Kaesdorf, Barbara; Leckie, Gregor; Leete, Jean; Perrin, Luc; Qiu, Chunfu; Ran, Iris; Schneider, George; Simmonds, Peter; Robinson, John

2005-02-01

This study was conducted to assess the performance of the Abbott laboratories LCx HCV RNA Quantitative Assay (LCx assay) in the clinical setting. Four clinical laboratories measured LCx assay precision, specificity, and linearity. In addition, a method comparison was conducted between the LCx assay and the Roche HCV Amplicor Monitor, version 2.0 (Roche Monitor 2.0) and the Bayer VERSANT HCV RNA 3.0 Assay (Bayer bDNA 3.0) quantitative assays. For precision, the observed LCx assay intra-assay standard deviation (S.D.) was 0.060-0.117 log IU/ml, the inter-assay S.D. was 0.083-0.133 log IU/ml, the inter-lot S.D. was 0.105-0.177 log IU/ml, the inter-site S.D. was 0.099-0.190 log IU/ml, and the total S.D. was 0.113-0.190 log IU/ml. The specificity of the LCx assay was 99.4% (542/545; 95% CI, 98.4-99.9%). For linearity, the mean pooled LCx assay results were linear (r=0.994) over the range of the panel (2.54-5.15 log IU/ml). A method comparison demonstrated a correlation coefficient of 0.881 between the LCx assay and Roche Monitor 2.0, 0.872 between the LCx assay and Bayer bDNA 3.0, and 0.870 between Roche Monitor 2.0 and Bayer bDNA 3.0. The mean LCx assay result was 0.04 log IU/ml (95% CI, -0.08, 0.01) lower than the mean Roche Monitor 2.0 result, but 0.57 log IU/ml (95% CI, 0.53, 0.61) higher than the mean Bayer bDNA 3.0 result. The mean Roche Monitor 2.0 result was 0.60 log IU/ml (95% CI, 0.56, 0.65) higher than the mean Bayer bDNA 3.0 result. The LCx assay quantitated genotypes 1-4 with statistical equivalency. The vast majority (98.9%, 278/281) of paired LCx assay-Roche Monitor 2.0 specimen results were within 1 log IU/ml. Similarly, 86.6% (240/277) of paired LCx assay and Bayer bDNA 3.0 specimen results were within 1 log, as were 85.6% (237/277) of paired Roche Monitor 2.0 and Bayer specimen results. These data demonstrate that the LCx assay may be used for quantitation of HCV RNA in HCV-infected individuals.

Field evaluation of Abbott Real Time HIV-1 Qualitative test for early infant diagnosis using dried blood spots samples in comparison to Roche COBAS Ampliprep/COBAS TaqMan HIV-1 Qual Test in Kenya

PubMed Central

Chang, Joy; Omuomo, Kenneth; Anyango, Emily; Kingwara, Leonard; Basiye, Frank; Morwabe, Alex; Shanmugam, Vedapuri; Nguyen, Shon; Sabatier, Jennifer; Zeh, Clement; Ellenberger, Dennis

2016-01-01

Timely diagnosis and treatment of infants infected with HIV are critical for reducing infant mortality. High-throughput automated diagnostic tests like Roche COBAS AmpliPrep/COBAS TaqMan HIV-1 Qual Test (Roche CAPCTM Qual) and the Abbott Real Time HIV-1 Qualitative (Abbott Qualitative) can be used to rapidly expand early infant diagnosis testing services. In this study, the performance characteristics of the Abbott Qualitative were evaluated using two hundred dried blood spots (DBS) samples (100 HIV-1 positive and 100 HIV-1 negative) collected from infants attending the antenatal facilities in Kisumu, Kenya. The Abbott Qualitative results were compared to the diagnostic testing completed using the Roche CAPCTM Qual in Kenya. The sensitivity and specificity of the Abbott Qualitative were 99.0% (95% CI: 95.0–100.0) and 100.0% (95% CI: 96.0–100.0), respectively, and the overall reproducibility was 98.0% (95% CI: 86.0–100.0). The limits of detection for the Abbott Qualitative and Roche CAPCTM Qual were 56.5 and 6.9 copies/mL at 95% CIs (p = 0.005), respectively. The study findings demonstrate that the Abbott Qualitative test is a practical option for timely diagnosis of HIV in infants. PMID:24726703

Field evaluation of Abbott Real Time HIV-1 Qualitative test for early infant diagnosis using dried blood spots samples in comparison to Roche COBAS Ampliprep/COBAS TaqMan HIV-1 Qual test in Kenya.

PubMed

Chang, Joy; Omuomo, Kenneth; Anyango, Emily; Kingwara, Leonard; Basiye, Frank; Morwabe, Alex; Shanmugam, Vedapuri; Nguyen, Shon; Sabatier, Jennifer; Zeh, Clement; Ellenberger, Dennis

2014-08-01

Timely diagnosis and treatment of infants infected with HIV are critical for reducing infant mortality. High-throughput automated diagnostic tests like Roche COBAS AmpliPrep/COBAS TaqMan HIV-1 Qual Test (Roche CAPCTM Qual) and the Abbott Real Time HIV-1 Qualitative (Abbott Qualitative) can be used to rapidly expand early infant diagnosis testing services. In this study, the performance characteristics of the Abbott Qualitative were evaluated using two hundred dried blood spots (DBS) samples (100 HIV-1 positive and 100 HIV-1 negative) collected from infants attending the antenatal facilities in Kisumu, Kenya. The Abbott Qualitative results were compared to the diagnostic testing completed using the Roche CAPCTM Qual in Kenya. The sensitivity and specificity of the Abbott Qualitative were 99.0% (95% CI: 95.0-100.0) and 100.0% (95% CI: 96.0-100.0), respectively, and the overall reproducibility was 98.0% (95% CI: 86.0-100.0). The limits of detection for the Abbott Qualitative and Roche CAPCTM Qual were 56.5 and 6.9copies/mL at 95% CIs (p=0.005), respectively. The study findings demonstrate that the Abbott Qualitative test is a practical option for timely diagnosis of HIV in infants. Published by Elsevier B.V.

Can the Roche hemolysis index be used for automated determination of cell-free hemoglobin? A comparison to photometric assays.

PubMed

Petrova, Darinka Todorova; Cocisiu, Gabriela Ariadna; Eberle, Christoph; Rhode, Karl-Heinz; Brandhorst, Gunnar; Walson, Philip D; Oellerich, Michael

2013-09-01

The aim of this study was to develop a novel method for automated quantification of cell-free hemoglobin (fHb) based on the HI (Roche Diagnostics). The novel fHb method based on the HI was correlated with fHb measured using the triple wavelength methods of both Harboe [fHb, g/L = (0.915 * HI + 2.634)/100] and Fairbanks et al. [fHb, g/L = (0.917 * HI + 2.131)/100]. fHb concentrations were estimated from the HI using the Roche Modular automated platform in self-made and commercially available quality controls, as well as samples from a proficiency testing scheme (INSTAND). The fHb using Roche automated HI results were then compared to results obtained using the traditional spectrophotometric assays for one hundred plasma samples with varying degrees of hemolysis, lipemia and/or bilirubinemia. The novel method using automated HI quantification on the Roche Modular clinical chemistry platform correlated well with results using the classical methods in the 100 patient samples (Harboe: r = 0.9284; Fairbanks et al.: r = 0.9689) and recovery was good for self-made controls. However, commercially available quality controls showed poor recovery due to an unidentified matrix problem. The novel method produced reliable determination of fHb in samples without interferences. However, poor recovery using commercially available fHb quality control samples currently greatly limits its usefulness. © 2013.

77 FR 2071 - Medical Devices; Availability of Safety and Effectiveness Summaries for Premarket Approval...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-13

.... Docket No. Applicant Trade name Approval date P100031, FDA-2011-M-0502...... Roche Diagnostics ELECSYS......... Roche Diagnostics ELECSYS ANTI-HBC IMMUNOASSAY, June 27, 2011. Corp.. ELECSYS PRECICONTROL ANTI-HBC FOR... IMMUNODIAGNOSTICS July 20, 2011. Diagnostics, PRODUCTS ANTI-HBE REAGENT PACK, Inc.. VITROS IMMUNODIAGNOSTIC PRODUCTS...

Analytical characteristics and comparative evaluation of Aptima HCV quant Dx assay with the Abbott RealTime HCV assay and Roche COBAS AmpliPrep/COBAS TaqMan HCV quantitative test v2.0.

PubMed

Worlock, A; Blair, D; Hunsicker, M; Le-Nguyen, T; Motta, C; Nguyen, C; Papachristou, E; Pham, J; Williams, A; Vi, M; Vinluan, B; Hatzakis, A

2017-04-04

The Aptima HCV Quant Dx assay (Aptima assay) is a fully automated quantitative assay on the Panther® system. This assay is intended for confirmation of diagnosis and monitoring of HCV RNA in plasma and serum specimens. The purpose of the testing described in this paper was to evaluate the performance of the Aptima assay. The analytical sensitivity, analytical specificity, precision, and linearity of the Aptima assay were assessed. The performance of the Aptima assay was compared to two commercially available HCV assays; the Abbott RealTime HCV assay (Abbott assay, Abbott Labs Illinois, USA) and the Roche COBAS Ampliprep/COBAS Taqman HCV Quantitative Test v2.0 (Roche Assay, Roche Molecular Systems, Pleasanton CA, USA). The 95% Lower Limit of Detection (LoD) of the assay was determined from dilutions of the 2nd HCV WHO International Standard (NIBSC 96/798 genotype 1) and HCV positive clinical specimens in HCV negative human plasma and serum. Probit analysis was performed to generate the 95% predicted detection limits. The Lower Limit of Quantitation (LLoQ) was established for each genotype by diluting clinical specimens and the 2nd HCV WHO International Standard (NIBSC 96/798 genotype 1) in HCV negative human plasma and serum. Specificity was determined using 200 fresh and 536 frozen HCV RNA negative clinical specimens including 370 plasma specimens and 366 serum specimens. Linearity for genotypes 1 to 6 was established by diluting armored RNA or HCV positive clinical specimens in HCV negative serum or plasma from 8.08 log IU/mL to below 1 log IU/mL. Precision was tested using a 10 member panel made by diluting HCV positive clinical specimens or spiking armored RNA into HCV negative plasma and serum. A method comparison was conducted against the Abbott assay using 1058 clinical specimens and against the Roche assay using 608 clinical specimens from HCV infected patients. In addition, agreement between the Roche assay and the Aptima assay using specimens with low HCV concentrations (

Venus: radar determination of gravity potential.

PubMed

Shapiro, I I; Pettengill, G H; Sherman, G N; Rogers, A E; Ingalls, R P

1973-02-02

We describe a method for the determination of the gravity potential of Venus from multiple-frequency radar measurements. The method is based on the strong frequency dependence of the absorption of radio waves in Venus' atmosphere. Comparison of the differing radar reflection intensities at several frequencies yields the height of the surface relative to a reference pressure contour; combination with measurements of round-trip echo delays allows the pressure, and hence the gravity potential contour, to be mapped relative to the mean planet radius. Since calibration data from other frequencies are unavailable, the absorption-sensitive Haystack Observatory data have been analyzed under the assumption of uniform surface reflectivity to yield a gravity equipotential contour for the equatorial region and a tentative upper bound of 6 x 10(-4) on the fractional difference of Venus' principal equatorial moments of inertia. The minima in the equipotential contours appear to be associated with topographic minima.

A multi-channel isolated power supply in non-equipotential circuit

NASA Astrophysics Data System (ADS)

Li, Xiang; Zhao, Bo-Wen; Zhang, Yan-Chi; Xie, Da

2018-04-01

A multi-channel isolation power supply is designed for the problems of different MOSFET or IGBT in the non-equipotential circuit in this paper. It mainly includes the square wave generation circuit, the high-frequency transformer and the three-terminal stabilized circuit. The first part is used to generate the 24V square wave, and as the input of the magnetic ring transformer. In the second part, the magnetic ring transformer consists of one input and three outputs to realize multi-channel isolation output. The third part can output different potential and realize non-equal potential function through the three-terminal stabilized chip. In addition, the multi-channel isolation power source proposed in this paper is Small size, high reliability and low price, and it is convenient for power electronic switches that operate on multiple different potentials. Therefore, the research on power supply of power electronic circuit has practical significance.

A comparative evaluation of the analytical performances of Capillarys 2 Flex Piercing, Tosoh HLC-723 G8, Premier Hb9210, and Roche Cobas c501 Tina-quant Gen 2 analyzers for HbA1c determination.

PubMed

Wu, Xiaobin; Chao, Yan; Wan, Zemin; Wang, Yunxiu; Ma, Yan; Ke, Peifeng; Wu, Xinzhong; Xu, Jianhua; Zhuang, Junhua; Huang, Xianzhang

2016-10-15

Haemoglobin A 1c (HbA 1c ) is widely used in the management of diabetes. Therefore, the reliability and comparability among different analytical methods for its detection have become very important. A comparative evaluation of the analytical performances (precision, linearity, accuracy, method comparison, and interferences including bilirubin, triglyceride, cholesterol, labile HbA 1c (LA 1c ), vitamin C, aspirin, fetal haemoglobin (HbF), and haemoglobin E (Hb E)) were performed on Capillarys 2 Flex Piercing (Capillarys 2FP) (Sebia, France), Tosoh HLC-723 G8 (Tosoh G8) (Tosoh, Japan), Premier Hb9210 (Trinity Biotech, Ireland) and Roche Cobas c501 (Roche c501) (Roche Diagnostics, Germany). A good precision was shown at both low and high HbA 1c levels on all four systems, with all individual CVs below 2% (IFCC units) or 1.5% (NGSP units). Linearity analysis for each analyzer had achieved a good correlation coefficient (R 2 > 0.99) over the entire range tested. The analytical bias of the four systems against the IFCC targets was less than ± 6% (NGSP units), indicating a good accuracy. Method comparison showed a great correlation and agreement between methods. Very high levels of triglycerides and cholesterol (≥ 15.28 and ≥ 8.72 mmol/L, respectively) led to falsely low HbA 1c concentrations on Roche c501. Elevated HbF induced false HbA 1c detection on Capillarys 2FP (> 10%), Tosoh G8 (> 30%), Premier Hb9210 (> 15%), and Roche c501 (> 5%). On Tosoh G8, HbE induced an extra peak on chromatogram, and significantly lower results were reported. The four HbA 1c methods commonly used with commercial analyzers showed a good reliability and comparability, although some interference may falsely alter the result.

Racialized Spaces in Teacher Discourse: A Critical Discourse Analysis of Place-Based Identities in Roche Bois, Mauritius

ERIC Educational Resources Information Center

Wiehe, Elsa M.

2013-01-01

This eleven-month ethnographic study puts critical discourse analysis in dialogue with postmodern conceptualizations of space and place to explore how eight educators talk about space and in the process, produce racialized spaces in Roche Bois, Mauritius. The macro-historical context of racialization of this urban marginalized community informs…

Before You Search that Locker.

ERIC Educational Resources Information Center

Dowling-Sendor, Benjamin

1998-01-01

In DesRoches v Caprio, federal district court ruled in favor of Jim DesRoches who had decided not to consent to a search of his backpack for a pair of allegedly stolen sneakers. Judge Robert G. Doumar decided the need to find the stolen sneakers did not outweigh the students' privacy interest and offered guidelines about school searches for stolen…

Notes on Experiments.

ERIC Educational Resources Information Center

Physics Education, 1989

1989-01-01

Described are the purposes, laboratory set-ups, and procedures of four classroom experiments: ultrasound speedometer; vibrating-bar depth gauge; folding three-dimensional model of equipotential surfaces; and a simple optical system for the reconstruction of images from computer-generated holograms. Diagrams and pictures are provided. (YP)

Baseline morning cortisol level as a predictor of pituitary-adrenal reserve: a comparison across three assays.

PubMed

Sbardella, Emilia; Isidori, Andrea M; Woods, Conor P; Argese, Nicola; Tomlinson, Jeremy W; Shine, Brian; Jafar-Mohammadi, Bahram; Grossman, Ashley B

2017-02-01

The short ACTH stimulation test (250 μg) is the dynamic test most frequently used to assess adrenal function. It is possible that a single basal cortisol could be used to predict the dynamic response, but research has been hampered by the use of different assays and thresholds. To propose a morning baseline cortisol criterion of three of the most commonly used modern cortisol immunoassays - Advia Centaur (Siemens), Architect (Abbott) and the Roche Modular System (Roche) - that could predict adrenal sufficiency. Observational, retrospective cross-sectional study at two centres. Retrospective analysis of the results of 1019 Short Synacthen tests (SSTs) with the Advia Centaur, 449 SSTs with the Architect and 2050 SSTs with the Roche Modular System assay. Serum cortisol levels were measured prior to injection of 250 μg Synacthen and after 30 min. Overall, we were able to collate data from a total of 3518 SSTs in 3571 patients. Using receiver-operator curve analysis, baseline cortisol levels for predicting passing the SST with 100% specificity were 358 nmol/l for Siemens, 336 nmol/l for Abbott and 506 nmol/l for Roche. Utilizing these criteria, 589, 158 and 578 SSTs, respectively, for Siemens, Abbott and Roche immunoassays could have been avoided. We have defined assay-specific morning cortisol levels that are able to predict the integrity of the hypothalamo-pituitary-adrenal axis. We propose that this represents a valid tool for the initial assessment of adrenal function and has the potential to obviate the need for dynamic testing in a significant number of patients. © 2016 John Wiley & Sons Ltd.

Homo-Roche Ester Derivatives By Asymmetric Hydrogenation and Organocatalysis

PubMed Central

Khumsubdee, Sakunchai; Zhou, Hua; Burgess, Kevin

2013-01-01

Asymmetric hydrogenation routes to homologs of The Roche ester tend to be restricted to hydrogenations of itaconic acid derivatives, ie substrates that contain a relatively unhindered, 1,1-disubstituted, alkene. This is because in hydrogenations mediated by RhP2 complexes, the typical catalysts, it is difficult to obtain high conversions using the alternative substrate for the same product, the isomeric trisubstituted alkenes (D in the text). However, chemoselective modification of the identical functional groups in itaconic acid derivatives are difficult, hence it would be favorable to use the trisubstituted alkene. Trisubstituted alkene substrates can be hydrogenated with high conversions using chiral analogs of Crabtree’s catalyst of the type IrN(carbene). This paper demonstrates such reactions are scalable (tens of grams) and can be manipulated to give optically pure homo-Roche ester chirons. Organocatalytic fluorination, chlorination, and amination of the homo-Roche building blocks was performed to demonstrate that they could be easily transformed into functionalized materials with two chiral centers and α,ω-groups that provide extensive scope for modifications. A synthesis of (S,S)- and (R,S)-γ-hydroxyvaline was performed to illustrate one application of the amination product. PMID:24219839

Computer-Drawn Field Lines and Potential Surfaces for a Wide Range of Field Configurations

ERIC Educational Resources Information Center

Brandt, Siegmund; Schneider, Hermann

1976-01-01

Describes a computer program that computes field lines and equipotential surfaces for a wide range of field configurations. Presents the mathematical technique and details of the program, the input data, and different modes of graphical representation. (MLH)

Predicting Life Expectancy for Pirfenidone in Idiopathic Pulmonary Fibrosis.

PubMed

Fisher, Mark; Nathan, Steven D; Hill, Christian; Marshall, Jade; Dejonckheere, Fred; Thuresson, Per-Olof; Maher, Toby M

2017-03-01

Conducting an adequately powered survival study in idiopathic pulmonary fibrosis (IPF) is challenging due to the rare nature of the disease and the need for extended follow-up. Consequently, registration trials of IPF treatments have not been designed to estimate long-term survival. To predict life expectancy for patients with IPF receiving pirfenidone versus best supportive care (BSC) in a population that met the inclusion criteria of patients enrolled in the ASCEND and CAPACITY trials. Kaplan-Meier survival data for pirfenidone and BSC were obtained from randomized controlled clinical studies (CAPACITY, ASCEND), an open-label extension study (RECAP), and the Inova Fairfax Hospital database. Data from the Inova registry were matched to the inclusion criteria of the CAPACITY and ASCEND trials. Life expectancy was estimated by the area under the curve of parametric survival distributions fit to the Kaplan-Meier data. Mean (95% confidence interval) life expectancy was calculated as 8.72 (7.65-10.15) years with pirfenidone and 6.24 (5.38-7.18) years with BSC. Therefore, pirfenidone improved life expectancy by 2.47 (1.26-4.17) years compared with BSC. In addition, treatment with pirfenidone recuperated 25% of the expected years of life lost due to IPF. Sensitivity analyses found that results were sensitive to the choice of parametric survival distribution, and alternative piecewise and parametric approaches. This analysis suggests that this population of patients with IPF has an improved life expectancy if treated with pirfenidone compared with BSC. This study was funded by InterMune International AG, a wholly owned Roche subsidiary since 2014. Fisher was previously employed by InterMune UK, a wholly owned Roche subsidiary, until July 2015. He is currently employed by FIECON, which has received funding from F. Hoffmann-La Roche for consulting services. Nathan has received consulting fees from Roche-Genentech and Boehringer Ingelheim. He is also on the speakers' bureau for Roche-Genentech and Boehringer Ingelheim and has received research funding from both companies. Hill was previously employed by InterMune UK until October 2014. Hill and Marshall are employees of MAP BioPharma, which has received funding from F. Hoffmann-La Roche for consulting services. Dejonckheere and Thuresson are employees of F. Hoffmann-La Roche. Maher has received grants, consulting fees, and speaker fees from GlaxoSmithKline and UCB, and grants from Novartis. He has also received consulting fees and speaker fees from AstraZeneca, Bayer, Biogen Idec, Boehringer Ingelheim, Cipla, Lanthio, InterMune International AG, F. Hoffmann-La Roche, Sanofi-Aventis, and Takeda. Maher is supported by a National Institute for Health Research Clinician Scientist Fellowship (NIHR Ref: CS: -2013-13-017). Study concept and design were contributed by Fisher, Hill, Marshall, and Dejonckheere. Fisher, Nathan, and Thuresson collected the data, along with Hill and Marshall. Data interpretation was performed by Fisher, Maher, Nathan, and Dejonckheere. The manuscript was written primarily by Fisher, along with Maher and Dejonckheere, and revised by Fisher and Maher, along with the other authors.

Verification of the harmonization of human epididymis protein 4 assays.

PubMed

Ferraro, Simona; Borille, Simona; Carnevale, Assunta; Frusciante, Erika; Bassani, Niccolò; Panteghini, Mauro

2016-10-01

Serum human epididymis protein 4 (HE4) has gained relevance as an ovarian cancer (OC) biomarker and new automated methods have replaced the first released manual EIA by tracing results to it. We verified agreement and bias of automated methods vs. EIA as well as possible effects on patients' management. One hundred and fifteen serum samples were measured by Abbott Architect i2000, Fujirebio Lumipulse G1200, Roche Modular E170, and Fujirebio EIA. Passing-Bablok regression was used to compare automated assays to EIA and agreement between methods was estimated by Lin's concordance correlation coefficient (CCC). The bias vs. EIA was estimated and compared to specifications derived from HE4 biological variation. Median (25th-75th percentiles) HE4 concentrations (pmol/L) were 84.5 (60.1-148.8) for EIA, 82.7 (50.3-153.9) for Abbott, 89.1 (55.2-154.9) for Roche, and 112.2 (67.8-194.2) for Fujirebio. Estimated regressions and agreements (95% confidence interval) were: Abbott=1.01(0.98-1.03) EIA-4.8(-7.5/-2.6), CCC=0.99(0.99-1.00); Roche=0.91(0.89-0.93) EIA+5.7(4.2/8.0), CCC=0.98(0.98-0.99); Fujirebio=1.20(1.17-1.24) EIA+ 2.4(-0.6/4.9), CCC=0.97(0.96-0.98). The average bias vs. EIA resulted within the desirable goal for Abbott [-3.3% (-6.1/-0.5)] and Roche [-0.2% (-3.0/2.5)]. However, while for Abbott the bias was constant and acceptable along the measurement concentration range, Roche bias increased up to -28% for HE4 values >250 pmol/L. Lumipulse showed a markedly positive bias [25.3% (21.8/28.8)]. Abbott and Roche assays exhibited a good comparability in the range of HE4 values around the previously recommended 140 pmol/L cut-off. For patient monitoring, however, the assay used for determining serial HE4 must not be changed as results from different systems in lower and higher concentration ranges can markedly differ.

A study of the electric field in an open magnetospheric model

NASA Technical Reports Server (NTRS)

Stern, D. P.

1972-01-01

The qualitative properties of an open magnetosphere and its electric field are examined and compared to a simple model of a dipole in a constant field and to actual observations. Many of these properties are found to depend on the separatrix, a curve connecting neutral points and separating different field-line regimes. In the simple model, the electric field in the central polar cap tends to point from dawn to dusk for a wide choice of external fields. Near the boundary of the polar cap electric equipotentials curve and become crescent-shaped, which may explain the correlation of polar magnetic variations with the azimuthal component of the interplanetary magnetic field, reported by Svalgaard. Modifications expected to occur in the actual magnetosphere are also investigated: in particular, it appears that bending of equipotentials may be reduced by cross-field flow during the merging of field lines and that open field lines connected to the polar caps emerge from a long and narrow slot extending along the tail.

Toxicologists in public health--Following the path of Louis Roche (based on the Louis Roche lecture "An accidental toxicologist in public health", Bordeaux, 2010).

PubMed

Dawson, Andrew H; Buckley, Nicholas A

2011-02-01

The global burden of clinical toxicology suggests a natural partnership with public health. This article reflects the content of a Louis Roche lecture given in 2010. HISTORICAL CONTEXT: Our practice and research in clinical toxicology has evolved from clinical cases to toxico-epidemiology to public health. This evolution in practice was initially unplanned but gained momentum and impact as we placed it more formally in a public health framework. This perspective is implicit in Louis Roche's call to "examine all aspects of the poisoning problem" and still provides a valuable starting point for any clinical toxicologist. Clinical toxicology has always had a patient centered focus but its greatest successes have been related to public health interventions. Our early failures and later success in pubic health toxicology correlated with our understanding of the importance of partnerships outside our field. The most rapid dissemination and implementation of information derived from research occur through apriori partnerships with other agencies and international partners. Addressing both local and global need has a number of bilateral synergies. Repositioning clinical toxicology into a public health framework increases access to strategic partnerships, research funds, and policy implementation while still addressing questions that are important to clinical practice.

FROM HOT JUPITERS TO SUPER-EARTHS VIA ROCHE LOBE OVERFLOW

DOE Office of Scientific and Technical Information (OSTI.GOV)

Valsecchi, Francesca; Rasio, Frederic A.; Steffen, Jason H.

2014-09-20

Through tidal dissipation in a slowly spinning host star, the orbits of many hot Jupiters may decay down to the Roche limit. We expect that the ensuing mass transfer will be stable in most cases. Using detailed numerical calculations, we find that this evolution is quite rapid, potentially leading to the complete removal of the gaseous envelope in a few gigayears, and leaving behind an exposed rocky core (a {sup h}ot super-Earth{sup )}. Final orbital periods are quite sensitive to the details of the planet's mass-radius relation and to the effects of irradiation and photo-evaporation, but could be as shortmore » as a few hours or as long as several days. Our scenario predicts the existence of planets with intermediate masses ({sup h}ot Neptunes{sup )} that should be found precisely at their Roche limit and in the process of losing mass through Roche lobe overflow. The observed excess of small single-planet candidate systems observed by Kepler may also be the result of this process. If so, the properties of their host stars should track those of the hot Jupiters. Moreover, the number of systems that produced hot Jupiters could be two to three times larger than one would infer from contemporary observations.« less

N-body simulations of star clusters

NASA Astrophysics Data System (ADS)

Engle, Kimberly Anne

1999-10-01

We investigate the structure and evolution of underfilling (i.e. non-Roche-lobe-filling) King model globular star clusters using N-body simulations. We model clusters with various underfilling factors and mass distributions to determine their evolutionary tracks and lifetimes. These models include a self-consistent galactic tidal field, mass loss due to stellar evolution, ejection, and evaporation, and binary evolution. We find that a star cluster that initially does not fill its Roche lobe can live many times longer than one that does initially fill its Roche lobe. After a few relaxation times, the cluster expands to fill its Roche lobe. We also find that the choice of initial mass function significantly affects the lifetime of the cluster. These simulations were performed on the GRAPE-4 (GRAvity PipE) special-purpose hardware with the stellar dynamics package ``Starlab.'' The GRAPE-4 system is a massively-parallel computer designed to calculate the force (and its first time derivative) due to N particles. Starlab's integrator ``kira'' employs a 4th- order Hermite scheme with hierarchical (block) time steps to evolve the stellar system. We discuss, in some detail, the design of the GRAPE-4 system and the manner in which the Hermite integration scheme with block time steps is implemented in the hardware.

Piaget, Play and Cognition, Revisited.

ERIC Educational Resources Information Center

Sutton-Smith, Brian

Piaget's early contribution to theorizing about play is discussed critically with reference to three major interrelated problems. These are: (1) that despite their equipotentiality in Piaget's theory of intelligence, imitation and play are not conceptualized as making an equal contribution to cognition, play taking a subordinate role; (2) that…

75 FR 38021 - Safety Zones; Annual Firework Displays Within the Captain of the Port, Puget Sound Area of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-01

...]13.466[min] W 150 City of Kenmore Fireworks Lake Forest Park......... 47[deg]39.0[min] N 122[deg]13... Port Townsend 48[deg]08.067[min] N 122[deg]46.467[min] W 175 Friday Harbor Independence Friday Harbor 48[deg]32.6[min] N 122[deg]00.467[min] W 250 Roche Harbor Fireworks Roche Harbor 48[deg]36.7[min] N...

Observations, Roche Lobe Analysis, and Period Study of the Eclipsing Contact Binary System GM Canum Venaticorum

NASA Astrophysics Data System (ADS)

Alton, K. B.; Nelson, R. H.

2018-06-01

GM CVn is an eclipsing W UMa binary system (P = 0.366984 d) which has been largely neglected since its variability was first detected during the ROTSE campaign (1999-2000). Other than a single unfiltered light curve (LC) no other photometric data have been published. LC data collected in three bandpasses (B, V, and Rc) at UnderOak Observatory (UO) produced three new times of minimum for GM CVn. These along with other eclipse timings from the literature were used to update the linear ephemeris. Roche modeling to produce synthetic LC fits to the observed data was accomplished using binary maker 3, wdwint56a, and phoebe v.31a. Newly acquired radial velocity data were pivotal to defining the absolute and geometric parameters for this partially eclipsing binary system. An unspotted solution achieved the best Roche model fits for the multi-color LCs collected in 2013.

Tidal disruption of inviscid protoplanets

NASA Technical Reports Server (NTRS)

Boss, Alan P.; Cameron, A. G. W.; Benz, W.

1991-01-01

Roche showed that equilibrium is impossible for a small fluid body synchronously orbiting a primary within a critical radius now termed the Roche limit. Tidal disruption of orbitally unbound bodies is a potentially important process for planetary formation through collisional accumulation, because the area of the Roche limit is considerably larger then the physical cross section of a protoplanet. Several previous studies were made of dynamical tidal disruption and different models of disruption were proposed. Because of the limitation of these analytical models, we have used a smoothed particle hydrodynamics (SPH) code to model the tidal disruption process. The code is basically the same as the one used to model giant impacts; we simply choose impact parameters large enough to avoid collisions. The primary and secondary both have iron cores and silicate mantles, and are initially isothermal at a molten temperature. The conclusions based on the analytical and numerical models are summarized.

LUNAR ACCRETION FROM A ROCHE-INTERIOR FLUID DISK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salmon, Julien; Canup, Robin M., E-mail: julien@boulder.swri.edu, E-mail: robin@boulder.swri.edu

2012-11-20

We use a hybrid numerical approach to simulate the formation of the Moon from an impact-generated disk, consisting of a fluid model for the disk inside the Roche limit and an N-body code to describe accretion outside the Roche limit. As the inner disk spreads due to a thermally regulated viscosity, material is delivered across the Roche limit and accretes into moonlets that are added to the N-body simulation. Contrary to an accretion timescale of a few months obtained with prior pure N-body codes, here the final stage of the Moon's growth is controlled by the slow spreading of themore » inner disk, resulting in a total lunar accretion timescale of {approx}10{sup 2} years. It has been proposed that the inner disk may compositionally equilibrate with the Earth through diffusive mixing, which offers a potential explanation for the identical oxygen isotope compositions of the Earth and Moon. However, the mass fraction of the final Moon that is derived from the inner disk is limited by resonant torques between the disk and exterior growing moons. For initial disks containing <2.5 lunar masses (M{sub Last-Quarter-Moon }), we find that a final Moon with mass > 0.8 M{sub Last-Quarter-Moon} contains {<=}60% material derived from the inner disk, with this material preferentially delivered to the Moon at the end of its accretion.« less

Numerical Simulations of Gaseous Disks Generated from Collisional Cascades at the Roche Limits of White Dwarf Stars

NASA Astrophysics Data System (ADS)

Kenyon, Scott J.; Bromley, Benjamin C.

2017-11-01

We consider the long-term evolution of gaseous disks fed by the vaporization of small particles produced in a collisional cascade inside the Roche limit of a 0.6 {M}⊙ white dwarf. Adding solids with radius {r}0 at a constant rate {\\dot{M}}0 into a narrow annulus leads to two distinct types of evolution. When {\\dot{M}}0≳ {\\dot{M}}0,{crit}≈ 3× {10}4 {({r}0/1{km})}3.92 {{g}} {{{s}}}-1, the cascade generates a fairly steady accretion disk where the mass transfer rate of gas onto the white dwarf is roughly {\\dot{M}}0 and the mass in gas is {M}g≈ 2.3× {10}22 ({\\dot{M}}0/{10}10 {{g}} {{{s}}}-1) (1500 {{K}}/{T}0) ({10}-3/α ) g, where T 0 is the temperature of the gas near the Roche limit and α is the dimensionless viscosity parameter. If {\\dot{M}}0≲ {\\dot{M}}0,{crit}, the system alternates between high states with large mass transfer rates and low states with negligible accretion. Although either mode of evolution adds significant amounts of metals to the white dwarf photosphere, none of our calculations yield a vertically thin ensemble of solids inside the Roche limit. X-ray observations can place limits on the mass transfer rate and test this model for metallic line white dwarfs.

Pharmaceutical lobbying and pandemic stockpiling of Tamiflu: a qualitative study of arguments and tactics.

PubMed

Vilhelmsson, Andreas; Mulinari, Shai

2017-08-09

Little is known about how pharmaceutical companies lobby authorities or experts regarding procurement or the use of vaccines and antivirals. This paper investigates how members of Denmark's pandemic planning committee experienced lobbying efforts by Roche, manufacturer of Tamiflu, the antiviral that was stockpiled before the 2009 A(H1N1) pandemic. Analysis of interviews with six of seven members of the Danish core pandemic committee, supplemented with documentary analysis. We sought to identify (1) arguments and (2) tactics used in lobbying, and to characterize interviewees' views on the impact of (3) lobbying and (4) scientific evidence on the decision to stockpile Tamiflu. Roche lobbied directly (in its own name) and through a seemingly independent third party. Roche used two arguments: (1) the procurement agreement had to be signed quickly because the drug would be delivered on a first-come, first-served basis and (2) Denmark was especially vulnerable to an influenza crisis because it had smaller Tamiflu stocks than other countries. Most interviewees suspected that lobbying had an impact on Tamiflu procurement. Our study highlights risks posed by pharmaceutical lobbying. Arguments and tactics deployed by Roche are likely to be repeated whenever many countries are negotiating drug procurements in a monopolistic market. © The Author 2017. Published by Oxford University Press on behalf of Faculty of Public Health.

Analytical and clinical performance of the new Fujirebio 25-OH vitamin D assay, a comparison with liquid chromatography-tandem mass spectrometry (LC-MS/MS) and three other automated assays.

PubMed

Saleh, Lanja; Mueller, Daniel; von Eckardstein, Arnold

2016-04-01

We evaluated the analytical and clinical performance of the new Lumipulse® G 25-OH vitamin D assay from Fujirebio, and compared it to a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and three other commercial automated assays. Total 25 hydroxy vitamin D (25(OH)D) levels were measured in 100 selected serum samples from our routine analysis with Fujirebio 25(OH)D assay. The results were compared with those obtained with LC-MS/MS and three other automated 25(OH)D assays (Abbott, Beckman, and Roche). The accuracy of each assay tested was evaluated against a Labquality reference serum panel for 25(OH)D (Ref!25OHD; University of Ghent). Intra- and inter-day imprecision of the Fujirebio 25(OH)D assay was <5%. Fujirebio 25(OH)D assay showed the highest correlation among the assays tested with the LC-MS/MS method (R=0.986). The mean relative bias obtained was -15.6% (Fujirebio), -12.7% (Beckman), -2.1% (Abbott) and 9.7% (Roche) as compared to LC-MS/MS. Comparison with the Labquality certified reference serum panel yielded a mean bias of -11.8% (Fujirebio), -14.1% (Beckman), 4.4% (Abbott) and 3.2% (Roche), respectively. Compared to LC-MS/MS, the sensitivity of different methods in detecting vitamin D insufficiency (<50 nmol/L) varied from 100% for the Fujirebio assay to 72.7% for Roche, and specificity ranged from 94.4% for Roche to 87.6% for Beckman. The Lumipulse G 25-OH vitamin D assay from Fujirebio demonstrated a good correlation with LC-MS/MS and some immunoassays. The performance of the assay is well-suited for routine 25(OH)D measurement in clinical serum samples. A correction for the observed negative bias vs. LC-MS/MS could be considered.

Real-time polymerase chain reaction detection of parvovirus B19 DNA in blood donations using a commercial and an in-house assay.

PubMed

Koppelman, M H G M; van Swieten, P; Cuijpers, H T M

2011-06-01

European regulations require testing of manufacturing plasma for parvovirus B19 (B19) DNA to limit the load of this virus to a maximum acceptable level of 10 IU/µL. To meet this requirement, most manufacturers introduced a test algorithm to identify and eliminate high-load donations before making large manufacturing pools of plasma units. Sanquin screens all donations using a commercial assay from Roche and an in-house assay. Between 2006 and 2009, 6.2 million donations were screened using two different polymerase chain reaction (PCR) assays targeting B19 DNA. Donations with B19 DNA loads of greater than 1 × 10(6) IU/mL showing significant differences in viral load between the two assays were further analyzed by sequencing analysis. A total of 396 donations with B19 DNA loads of greater than 1 × 10(6) IU/mL were identified. Fifteen samples (3.8%) had discordant test results; 10 samples (2.5%) were underquantified by the Roche assay, two samples (0.5%) were underquantified by the in-house assay, and three samples (0.8%) were not detected by the Roche assay. Sequencing analysis revealed mismatches in primer and probe-binding regions. Phylogenetic analysis showed that 12 samples were B19 Genotype 1. The three samples not detected by the Roche assay were B19 Genotype 2. This study shows that 3.8% of the viremic B19 DNA-positive donations are not quantified correctly by the Roche or in-house B19 DNA assays. B19 Genotype 1 isolates showing incorrect test results are more common than B19 Genotype 2 or 3 isolates. Newly designed B19 PCR assays for blood screening should preferably have multiplexed formats targeting multiple regions of the B19 genome. © 2010 American Association of Blood Banks.

[Experimental studies on the diffusion of excitation on the right ventricular surface in the dog, during normal and stimulated beats].

PubMed

Arisi, G; Macchi, E; Baruffi, S; Musso, E; Spaggiari, S; Stilli, D; Taccardi, B

1982-01-01

Previous work on the spread of excitation on the dog's ventricular surface enabled us to locate up to 30 breakthrough points (BKTPs) where excitation reaches the ventricular surface. In particular the equipotential contour maps enabled us to detect 3 to 5 BKTPs on the anterior right ventricular surface, near the a-v groove when a large part of ventricular surface was still at rest. With a view to investigating the mechanism underlying the early excitation of these basal regions, we stimulated the heart at several right ventricular BKTPs and in other points located at a distance from the BKTPs. The instantaneous equipotential maps showed that after stimulation most right ventricular BKTPs remained in the same position as observed the normal beats. The early appearance of epicardial wavefronts in the basal region and generally in other areas of the right ventricle was attributed to the rapid propagation of excitation waves through the Purkinje network, probably associated to a short transmural crossing time, due to a local thinness of the ventricular wall.

Fourier analysis of polar cap electric field and current distributions

NASA Technical Reports Server (NTRS)

Barbosa, D. D.

1984-01-01

A theoretical study of high-latitude electric fields and currents, using analytic Fourier analysis methods, is conducted. A two-dimensional planar model of the ionosphere with an enhanced conductivity auroral belt and field-aligned currents at the edges is employed. Two separate topics are treated. A field-aligned current element near the cusp region of the polar cap is included to investigate the modifications to the convection pattern by the east-west component of the interplanetary magnetic field. It is shown that a sizable one-cell structure is induced near the cusp which diverts equipotential contours to the dawnside or duskside, depending on the sign of the cusp current. This produces characteristic dawn-dusk asymmetries to the electric field that have been previously observed over the polar cap. The second topic is concerned with the electric field configuration obtained in the limit of perfect shielding, where the field is totally excluded equatorward of the auroral oval. When realistic field-aligned current distributions are used, the result is to produce severely distorted, crescent-shaped equipotential contours over the cap. Exact, analytic formulae applicable to this case are also provided.

The narrow rings of Jupiter, Saturn and Uranus

NASA Technical Reports Server (NTRS)

Dermott, S. F.; Murray, C. D.; Sinclair, A. T.

1980-01-01

The origin of the newly discovered narrow ring systems around Jupiter, Saturn and Uranus is considered. It is pointed out that both the Uranian and Jovian ring systems have mean orbital radii of 1.8 planetary radii and lie within the Roche zones of their respective planets, and it is suggested that the Jovian ring is the product of the disintegration of a satellite that entered the Roche zone, and that large numbers of small particles are now in horseshoe orbits about the Lagrangian equilibrium points of the remnant chunks. Analysis of the path of a ring particle in a horseshoe orbit is shown to result in ring structures in agreement with those observed for the circular rings of Jupiter and the highly eccentric ring of Uranus. The stability of these ring systems is then considered, and it is suggested that the F ring of Saturn, which lies outside the Roche zone, represents primordial matter not yet accreted by small satellites just inside the Mimas first-order resonances.

A comparative evaluation between real time Roche COBas TAQMAN 48 HCV and bDNA Bayer Versant HCV 3.0.

PubMed

Giraldi, Cristina; Noto, Alessandra; Tenuta, Robert; Greco, Francesca; Perugini, Daniela; Spadafora, Mario; Bianco, Anna Maria Lo; Savino, Olga; Natale, Alfonso

2006-10-01

The HCV virus is a common human pathogen made of a single stranded RNA genome with 9600nt. This work compared two different commercial methods used for HCV viral load, the bDNA Bayer Versant HCV 3.0 and the RealTime Roche COBAS TaqMan 48 HCV. We compared the reproducibility and linearity of the two methods. Seventy-five plasma samples with genotypes 1 to 4, which represent the population (45% genotype 1; 24% genotype 2; 13% genotype 3; 18% genotype 4) were directly processed with the Versanto method based upon signal amplification; the same samples were first extracted (COBAS Ampliprep - TNAI) and then amplified using RealTime PCR (COBAS TaqMan 48). The results obtained indicate the same performance for both methods if they have genotype 1, but in samples with genotypes 2, 3 and 4 the RealTime PCR Roche method gave an underestimation in respect to the Bayer bDNA assay.

Accretion disks around black holes

NASA Technical Reports Server (NTRS)

Abramowicz, M. A.

1994-01-01

The physics of accretion flow very close to a black hole is dominated by several general relativistic effects. It cannot be described by the standard Shakura Sunyaev model or by its relativistic version developed by Novikov and Thome. The most important of these effects is a dynamical mass loss from the inner edge of the disk (Roche lobe overflow). The relativistic Roche lobe overflow induces a strong advective cooling, which is sufficient to stabilize local, axially symmetric thermal and viscous modes. It also stabilizes the non-axially-symmetric global modes discovered by Papaloizou and Pringle. The Roche lobe overflow, however, destabilizes sufficiently self-gravitating accretion disks with respect to a catastrophic runaway of mass due to minute changes of the gravitational field induced by the changes in the mass and angular momentum of the central black hole. One of the two acoustic modes may become trapped near the inner edge of the disk. All these effects, absent in the standard model, have dramatic implications for time-dependent behavior of the accretion disks around black holes.

Comparison of an assay using signal amplification of the heat-dissociated p24 antigen with the Roche Monitor human immunodeficiency virus RNA assay.

PubMed

Pascual, Alvaro; Cachafeiro, Ada; Funk, Michele L; Fiscus, Susan A

2002-07-01

We compared an assay using signal amplification of a heat-dissociated p24 antigen (HDAg) with the Roche Monitor human immunodeficiency virus (HIV) RNA assay. The two assays gave comparable results when 130 specimens from 130 patients were tested (r = 0.60, P < 0.0001). The HDAg assay was almost as sensitive (85%) as the Roche HIV RNA kit (95%), just as specific (25 negative results from 25 HIV seronegative volunteers [100%]), less variable (mean log standard deviation of 0.07 compared to 0.11 when eight specimens were tested three or four times), and less expensive (reagent and labor costs, $8 versus $75). The assay appeared to be useful for monitoring established patients (n = 17) and identifying seroconverters (n = 4). HIV subtypes A to F were all recognized. This assay should be useful for monitoring patients in resource-poor countries and for monitoring vaccine recipients.

Comparison of Two Commercial Automated Nucleic Acid Extraction and Integrated Quantitation Real-Time PCR Platforms for the Detection of Cytomegalovirus in Plasma

PubMed Central

Tsai, Huey-Pin; Tsai, You-Yuan; Lin, I-Ting; Kuo, Pin-Hwa; Chen, Tsai-Yun; Chang, Kung-Chao; Wang, Jen-Ren

2016-01-01

Quantitation of cytomegalovirus (CMV) viral load in the transplant patients has become a standard practice for monitoring the response to antiviral therapy. The cut-off values of CMV viral load assays for preemptive therapy are different due to the various assay designs employed. To establish a sensitive and reliable diagnostic assay for preemptive therapy of CMV infection, two commercial automated platforms including m2000sp extraction system integrated the Abbott RealTime (m2000rt) and the Roche COBAS AmpliPrep for extraction integrated COBAS Taqman (CAP/CTM) were evaluated using WHO international CMV standards and 110 plasma specimens from transplant patients. The performance characteristics, correlation, and workflow of the two platforms were investigated. The Abbott RealTime assay correlated well with the Roche CAP/CTM assay (R2 = 0.9379, P<0.01). The Abbott RealTime assay exhibited higher sensitivity for the detection of CMV viral load, and viral load values measured with Abbott RealTime assay were on average 0.76 log10 IU/mL higher than those measured with the Roche CAP/CTM assay (P<0.0001). Workflow analysis on a small batch size at one time, using the Roche CAP/CTM platform had a shorter hands-on time than the Abbott RealTime platform. In conclusion, these two assays can provide reliable data for different purpose in a clinical virology laboratory setting. PMID:27494707

A new primate assemblage from La Verrerie de Roches (Middle Eocene, Switzerland).

PubMed

Minwer-Barakat, Raef; Marigó, Judit; Becker, Damien; Costeur, Loïc

2017-12-01

Primates reached a great abundance and diversity during the Eocene, favored by warm temperatures and by the development of dense forests throughout the Northern Hemisphere. Here we describe new primate material from La Verrerie de Roches, a Middle Eocene karstic infill situated in the Jura Region (Switzerland), consisting of more than 80 dental remains. The primate assemblage from La Verrerie de Roches includes five different taxa. The best represented primate is Necrolemur aff. anadoni, similar in size and overall morphology to Necrolemur anadoni but resembling in some features the younger species Necrolemur antiquus. Microchoerines are also represented by two species of Pseudoloris, P. pyrenaicus and Pseudoloris parvulus, constituting the unique joint record of these two species known up to now. Remains of Adapiformes are limited to one isolated tooth of a large anchomomyin and another tooth belonging to the small adapine Microadapis cf. sciureus. The studied primate association allows assigning La Verrerie de Roches to the Robiacian Land Mammal Age. More specifically, this site can be confidently situated between the MP15 and MP16 reference levels, although the primate assemblage probably indicates some degree of temporal mixing. This is the first record of P. pyrenaicus and a form closely related to N. anadoni out of the Iberian Peninsula. The identification of these microchoerines in Switzerland gives further support to the connection of NE Spain and Central Europe during the Middle Eocene. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pharmaceutical quality of generic isotretinoin products, compared with Roaccutane.

PubMed

Taylor, Peter W; Keenan, Michael H J

2006-03-01

Isotretinoin is the drug of choice for the management of severe recalcitrant nodular acne. Several generic products are available. However, their pharmaceutical quality, in particular particle size distribution, which may affect safety and efficacy is unknown. Hence, prescribing of some generic products may be problematic. To assess the pharmaceutical quality of 14 generic isotretinoin products compared with Roaccutane (F. Hoffmann-La Roche Ltd). Tests were performed according to Roche standard procedures, European and US pharmacopoeia specifications. Tests included isotretinoin content, identity and amount of impurities and degradation products, effect of accelerated shelf-life studies on stability, particle size distribution and composition of non-active ingredients. The 14 isotretinoin products differed by 30-fold in median particle size and showed variation in their non-active ingredients. The average isotretinoin content of Acnotin and Acne-Tretin fell outside the 95-105% Roche specifications. Following accelerated shelf-life tests, only four products retained isotretinoin content within Roche specifications, whilst Acne-Tretin (the only powder formulation) lost 72.5% isotretinoin content. Two generic products exceeded the +/- 2% specification (Ph. Eur.) and a further three exceeded the +/- 1% (USP) for tretinoin content, eight exceeded the 2.54% specification for total impurities and six contained >or= 5 unknown impurities. Isotretinoin-5.6-epoxide content exceeded the 1.04% specification in five generic products. Thirteen generic products failed to match Roaccutane in one or more tests and 11 failed in three or more tests. It cannot be assumed that all generic isotretinoin products are as therapeutically effective or safe as Roaccutane.

Clinical evaluation of the new Roche platform of serological and molecular cytomegalovirus-specific assays in the diagnosis and prognosis of congenital cytomegalovirus infection.

PubMed

Chiereghin, Angela; Pavia, Claudia; Gabrielli, Liliana; Piccirilli, Giulia; Squarzoni, Diego; Turello, Gabriele; Gibertoni, Dino; Simonazzi, Giuliana; Capretti, Maria Grazia; Lanari, Marcello; Lazzarotto, Tiziana

2017-10-01

Clinical evaluation of the Elecsys ® CMV IgM, IgG, IgG Avidity and COBAS AmpliPrep/COBAS TaqMan CMV (COBAS CMV) assays (Roche Diagnostics AG) in the diagnosis and prognosis of congenital CMV infection was performed. In this study, 150 preselected clinical samples (50 primary infection sera, 50 amniotic fluid [AF] and 50 newborn urine) were processed using Roche serological/molecular CMV-specific tests. Results were compared with those obtained by routine assays (comparator assays). The Elecsys ® CMV IgM and IgG assays showed a perfect agreement (100%) with the comparator assays. Using the combination of the Elecsys ® CMV IgM and IgG Avidity assays results, a primary infection was identified in 100% of cases. Inappropriate avidity CMV IgG values in two samples with very low IgG values (<6 AU/mL) were observed. COBAS CMV assay showed an agreement equal to 98% and 100% with comparator assays by processing AF and urine samples, respectively. Among AF with quantitative results, Lin's concordance correlation was 0.933 and comparator-COBAS CMV assays gave CMV-DNA loads differing by <0.5 log 10 DNA. Finally, higher CMV-DNA levels in AF samples were associated with a symptomatic outcome (p=0.003). The Roche CMV-specific assays compared well with the comparator assays, thus providing to be suitable for clinical use. Copyright © 2017 Elsevier B.V. All rights reserved.

Clinical performance of three bolus calculators in subjects with type 1 diabetes mellitus: a head-to-head-to-head comparison.

PubMed

Zisser, Howard; Wagner, Robin; Pleus, Stefan; Haug, Cornelia; Jendrike, Nina; Parkin, Chris; Schweitzer, Matthias; Freckmann, Guido

2010-12-01

Insulin pump systems now provide automated bolus calculators (ABCs) that electronically calculate insulin boluses to address carbohydrate intake and out-of-range blood glucose (bG) levels. We compared the efficacy of three ABCs (Accu-Chek(®) Combo [Roche Insulin Delivery Systems (IDS), Inc., Fishers, IN, a member of the Roche Group], Animas(®) 2020 [Animas Corp., West Chester, PA, a Johnson and Johnson company], and MiniMed Paradigm Bolus Wizard(®) [Medtronic MiniMed, Northridge, CA]) to safely reduce postprandial hyperglycemia in type 1 diabetes mellitus (T1DM). T1DM subjects (n = 24) were recruited at a single center for a prospective, triple crossover study. ABCs with the programmed target range (80-140 mg/dL) were used in random order. Postprandial hyperglycemia was induced by reducing the calculated bolus by 25%. Two hours after test meals, the ABCs were allowed to determine whether a correction bolus was needed. Differences between 6-h bG values after test meals that achieved 2-h postprandial hyperglycemia and the mean of the target range (110 mg/dL) were determined. The mean difference between 6-h bG levels following test meals and the 110 mg/dL bG target with the MiniMed device (47.4 ± 31.8 mg/dL) was significantly higher than the Animas (17.3 ± 30.9 mg/dL) and Roche IDS (18.8 ± 33.8 mg/dL) devices (P = 0.0022 and P = 0.0049, respectively). The number of meals with 2-h postprandial hyperglycemia and bG levels at 2 h was similar. Roche IDS and Animas devices recommended correction boluses significantly (P = 0.0001 and P = 0.0002, respectively) more frequently than the MiniMed device. ABC use was not associated with severe hypoglycemia. There was no significant difference in the rate of mild hypoglycemia (bG <60 mg/dL not requiring assistance) among the three groups (Roche IDS and Animas, n = 2; MiniMed, n = 0). In this study, the Roche IDS and Animas devices were more efficacious in controlling postprandial hyperglycemia than the MiniMed device. This may be due, in part, to differences in ABC setup protocols and algorithms. Use of ABCs can assist in controlling postprandial glycemia without significant hypoglycemia.

High voltage variable diameter insulator

DOEpatents

Vanacek, D.L.; Pike, C.D.

1982-07-13

A high voltage feedthrough assembly having a tubular insulator extending between the ground plane ring and the high voltage ring. The insulator is made of Pyrex and decreases in diameter from the ground plane ring to the high voltage ring, producing equipotential lines almost perpendicular to the wall of the insulator to optimize the voltage-holding capability of the feedthrough assembly.

Effect of the traditional Chinese medicines Chan Su, Lu-Shen-Wan, Dan Shen, and Asian ginseng on serum digoxin measurement by Tina-quant (Roche) and Synchron LX system (Beckman) digoxin immunoassays.

PubMed

Chow, Leonard; Johnson, Myrtle; Wells, Alice; Dasgupta, Amitava

2003-01-01

Chan Su, Lu-Shen-Wan, Dan Shen, and Asian ginseng are traditionally used to treat a number of conditions, including cardiovascular disease. All of these traditional Chinese medicines exhibit cardioactive properties. Digoxin is a cardioactive drug with a narrow therapeutic range (0.8-1.9 ng/mL). A patient taking digoxin may also take these Chinese medicines for their cardiotonic effects. Moreover, the active components of these medicines that are responsible for cardiotonic effects bear structural similarities to digoxin. Therefore, we studied the potential interference of these Chinese medicines with two digoxin immunoassays--the Tina-quant (Roche Diagnostics) and the Beckman (Synchron LX system)--and compared the values with the fluorescence polarization immunoassay (FPIA; Abbott Laboratories). When very small amounts (2-5 microL) of aqueous extract of Chan Su or Lu-Shen-Wan were added to drug-free serum, we observed high digoxin-like immunoreactivity with the FPIA. In contrast, when ethyl acetate extract of Dan Shen or microliter amounts of ginseng extract were added to drug-free serum, we observed modest digoxin-like immunoreactivity with the FPIA, but no apparent digoxin activity with the Roche and Beckman digoxin immunoassays. When aliquots of a digoxin pool prepared from patients receiving digoxin were supplemented with these Chinese medicines, we observed the most significant interference with the FPIA. The presence of endogenous digoxin-like immunoreactive substances can have additive effects with these Chinese medicines and falsely increase apparent digoxin levels by the FPIA. On the other hand, the Roche and Beckman assays were free from interference from DLIS but showed significant interference from Chan Su and Lu-Shen-Wan. We conclude that the FPIA showed the most significant interference from all four of the Chinese medicines we studied. However, the Roche and Beckman assays showed no interference from two (Dan Shen and Asian ginseng) of the four Chinese medicines we studied. Copyright 2003 Wiley-Liss, Inc.

Analytical characteristics and comparative evaluation of Aptima HIV-1 Quant Dx assay with Ampliprep/COBAS TaqMan HIV-1 test v2.0.

PubMed

Hatzakis, Angelos; Papachristou, Helen; Nair, Sangeetha J; Fortunko, Jacqueline; Foote, Tracy; Kim, HeeCheol; Peling, Tashi L; Worlock, Andrew J

2016-10-21

Quantitation of HIV-RNA is critically important for diagnosis, prognosis, treatment, monitoring and assessment of infectivity in HIV-1 infection. The objective of this study was to assess performance characteristics of the Aptima HIV-1 Quant Dx assay (Aptima), a new transcription mediated amplification (TMA), fully integrated and automated assay from Hologic Inc., San Diego, CA, USA. The analytical sensitivity, analytical specificity, precision and detection of HIV-1 subtypes were tested based on commercially available international standards or panels. A selected group of 244 anti-HIV-1 (+) plasma samples was used for comparison with Roche COBAS Ampliprep/COBAS TaqMan HIV- 1 test v2.0 (Roche CAP/CTM), (Roche Molecular Systems, Pleasanton, CA). The 50 and 95 % limit of detection were estimated at 4.9 (95 % CI 3.9-5.7) and 17.6 (15.2-21.2) IU/mL respectively. The specificity was found 99.83 (99.06-99.97) %. The standard deviations and coefficient of variations for panels with 50 and 100 copies/mL (1.7 and 2 log copies/mL) were 0.14 log copies/mL (8.67 %CV) and 0.18 log copies/mL (9.91 %CV) respectively. The detection rate for Aptima and Roche assays was 220/244 (90.2 %) and 217/244 (88.9 %) respectively. The Aptima assay is a sensitive, specific, precise and accurate test for measuring HIV-1 viral loads and for the detection of HIV-1 infections.

Comparison of the Abbott m2000 HIV-1 Real-Time and Roche AMPLICOR Monitor v1.5 HIV-1 assays on plasma specimens from Rakai, Uganda.

PubMed

Ssebugenyi, I; Kizza, A; Mpoza, B; Aluma, G; Boaz, I; Newell, K; Laeyendecker, O; Shott, J P; Serwadda, D; Reynolds, S J

2011-07-01

The need for viral load (VL) monitoring of HIV patients receiving antiretroviral therapy (ART) in resource-limited settings (RLS) has become apparent with studies showing the limitations of immunological monitoring. We compared the Abbott m2000 Real-Time (Abbott) HIV-1 assay with the Roche AMPLICOR Monitor v1.5 (Roche) HIV-1 assay over a range of VL concentrations. Three hundred and eleven plasma samples were tested, including 164 samples from patients on ART ≥ six months and 147 from ART-naïve patients. The Roche assay detected ≥400 copies/mL in 158 (50.8%) samples. Of these, Abbott produced 145 (91.8%) detectable results ≥400 copies/mL; 13 (8.2%) samples produced discrepant results. Concordance between the assays for detecting HIV-1 RNA ≥400 copies/mL was 95.8% (298/311). The sensitivity, specificity, positive predictive value and negative predictive value of Abbott to detect HIV-1 RNA ≥400 copies/mL were 91.8%, 100%, 100% and 92.2%, respectively. For the 151 samples with HIV-1 RNA ≥400 copies/mL for both assays, a good linear correlation was found (r = 0.81, P < 0.0001; mean difference, 0.05). The limits of agreement were -0.97 and 1.07 log(10) copies/mL (mean ± 2 SD). The Abbott assay performed well in our setting, offering an alternative methodology for HIV-1 VL for laboratories with realtime polymerase chain reaction (PCR) capacity.

Exo-Mercury Analogues and the Roche Limit for Close-Orbiting Rocky Planets

NASA Astrophysics Data System (ADS)

Rogers, Leslie A.; Price, Ellen

2015-12-01

The origin of Mercury's enhanced iron content is a matter of ongoing debate. The characterization of rocky exoplanets promises to provide new independent insights on this topic, by constraining the occurrence rate and physical and orbital properties of iron-enhanced planets orbiting distant stars. The ultra-short-period transiting planet candidate KOI-1843.03 (0.6 Earth-radius, 4.245 hour orbital period, 0.46 Solar-mass host star) represents the first exo-Mercury planet candidate ever identified. For KOI-1843.03 to have avoided tidal disruption on such a short orbit, Rappaport et al. (2013) estimate that it must have a mean density of at least 7g/cc and be at least as iron rich as Mercury. This density lower-limit, however, relies upon interpolating the Roche limits of single-component polytrope models, which do not accurately capture the density profiles of >1000 km differentiated rocky bodies. A more exact calculation of the Roche limit for the case of rocky planets of arbitrary composition and central concentration is needed. We present 3D interior structure simulations of ultra-short-period tidally distorted rocky exoplanets, calculated using a modified version of Hachisu’s self-consistent field method and realistic equations of state for silicates and iron. We derive the Roche limits of rocky planets as a function of mass and composition, and refine the composition constraints on KOI-1843.03. We conclude by discussing the implications of our simulations for the eventual characterization of short-period transiting planets discovered by K2, TESS, CHEOPS and PLATO.

Equilibrium figures in geodesy and geophysics.

NASA Astrophysics Data System (ADS)

Moritz, H.

There is an enormous literature on geodetic equilibrium figures, but the various works have not always been interrelated, also for linguistic reasons (English, French, German, Italian, Russian). The author attempts to systematize the various approaches and to use the standard second-order theory for a study of the deviation of the actual earth and of the equipotential reference ellipsoid from an equilibrium figure.

The gravitational potential of a homogeneous polyhedron or don't cut corners

NASA Technical Reports Server (NTRS)

Werner, Robert A.

1994-01-01

A polyhedron can model irregularly shaped objects such as asteroids, comet nuclei, and small planetary satellites. With minor effort, such a model can incorporate important surface features such as large craters. Here we develop closed-form expressions for the exterior gravitational potential and acceleration components due to a constant-density polyhedron. An equipotential surface of Phobos is illustrated.

The Robin Hood method - A novel numerical method for electrostatic problems based on a non-local charge transfer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lazic, Predrag; Stefancic, Hrvoje; Abraham, Hrvoje

2006-03-20

We introduce a novel numerical method, named the Robin Hood method, of solving electrostatic problems. The approach of the method is closest to the boundary element methods, although significant conceptual differences exist with respect to this class of methods. The method achieves equipotentiality of conducting surfaces by iterative non-local charge transfer. For each of the conducting surfaces, non-local charge transfers are performed between surface elements, which differ the most from the targeted equipotentiality of the surface. The method is tested against analytical solutions and its wide range of application is demonstrated. The method has appealing technical characteristics. For the problemmore » with N surface elements, the computational complexity of the method essentially scales with N {sup {alpha}}, where {alpha} < 2, the required computer memory scales with N, while the error of the potential decreases exponentially with the number of iterations for many orders of magnitude of the error, without the presence of the Critical Slowing Down. The Robin Hood method could prove useful in other classical or even quantum problems. Some future development ideas for possible applications outside electrostatics are addressed.« less

Galactic Tidal Shocks Effects in Globular Clusters

NASA Astrophysics Data System (ADS)

Cruz, F.; Aguilar, L.

2001-07-01

We present results of a set of N--Body simulations of 105--particle King models in the presence of a realistic Galactic tidal field. Tidal effects over a cluster are dominated by two processes, differentiated by the way they produc e mass loss in the system. The first one is the Roche lobe overflow, which depend s directly on the ratio of cluster to the Roche lobe size. The second process is tidal heating, produced by the time varying part of the Galactic tide, which injects energy directly on the orbits of the stars inside the cluster.

[Measurement of the electric field of the heart in a homogeneous volume conductor].

PubMed

Tsukerman, B M; Titomir, L I

1975-01-01

The paper describes a technique and some results of experimental measurements of electrical potentials generated by an isolated dog heart in homogeneous conductor, drawing equipotential maps of the field, and calculating the characteristics of the dipole equivalent generator of the heart. The form of potential distribution on a spherical surface around the heart and its ideal orthogonal vectorcardiograms are discussed.

Precision, accuracy, cross reactivity and comparability of serum indices measurement on Abbott Architect c8000, Beckman Coulter AU5800 and Roche Cobas 6000 c501 clinical chemistry analyzers.

PubMed

Nikolac Gabaj, Nora; Miler, Marijana; Vrtarić, Alen; Hemar, Marina; Filipi, Petra; Kocijančić, Marija; Šupak Smolčić, Vesna; Ćelap, Ivana; Šimundić, Ana-Maria

2018-04-25

The aim of our study was to perform verification of serum indices on three clinical chemistry platforms. This study was done on three analyzers: Abbott Architect c8000, Beckman Coulter AU5800 (BC) and Roche Cobas 6000 c501. The following analytical specifications were verified: precision (two patient samples), accuracy (sample with the highest concentration of interferent was serially diluted and measured values compared to theoretical values), comparability (120 patients samples) and cross reactivity (samples with increasing concentrations of interferent were divided in two aliquots and remaining interferents were added in each aliquot. Measurements were done before and after adding interferents). Best results for precision were obtained for the H index (0.72%-2.08%). Accuracy for the H index was acceptable for Cobas and BC, while on Architect, deviations in the high concentration range were observed (y=0.02 [0.01-0.07]+1.07 [1.06-1.08]x). All three analyzers showed acceptable results in evaluating accuracy of L index and unacceptable results for I index. The H index was comparable between BC and both, Architect (Cohen's κ [95% CI]=0.795 [0.692-0.898]) and Roche (Cohen's κ [95% CI]=0.825 [0.729-0.922]), while Roche and Architect were not comparable. The I index was not comparable between all analyzer combinations, while the L index was only comparable between Abbott and BC. Cross reactivity analysis mostly showed that serum indices measurement is affected when a combination of interferences is present. There is heterogeneity between analyzers in the hemolysis, icteria, lipemia (HIL) quality performance. Verification of serum indices in routine work is necessary to establish analytical specifications.

Is there a suitable point-of-care glucose meter for tight glycemic control? Evaluation of one home-use and four hospital-use meters in an intensive care unit.

PubMed

Gijzen, Karlijn; Moolenaar, David L J; Weusten, Jos J A M; Pluim, Hendrik J; Demir, Ayse Y

2012-11-01

Implementation of tight glycemic control (TGC) and avoidance of hypoglycemia in intensive care unit (ICU) patients require frequent analysis of blood glucose. This can be achieved by accurate point-of-care (POC) hospital-use glucose meters. In this study one home-use and four different hospital-use POC glucose meters were evaluated in critically ill ICU patients. All patients (n = 80) requiring TGC were included in this study. For each patient three to six glucose measurements (n = 390) were performed. Blood glucose was determined by four hospital-use POC glucose meters, Roche Accu-Check Inform II System, HemoCue Glu201DM, Nova StatStrip, Abbott Precision Xceed Pro, and one home-use POC glucose meter, Menarini GlucoCard Memory PC. The criteria described in ISO 15197, Dutch TNO quality guideline and in NACB/ADA-2011 were applied in the comparisons. According to the ISO 15197, the percentages of the measured values that fulfilled the criterion were 99.5% by Roche, 95.1% by HemoCue, 91.0% by Nova, 96.6% by Abbott, and 63.3% by Menarini. According to the TNO quality guideline these percentages were 96.1% , 91.0% , 81.8% , 94.2% , and 47.7% , respectively. Application of the NACB/ADA guideline resulted in percentages of 95.6%, 89.2%, 77.9%, 93.4%, and 45.4%, respectively. When ISO 15197 was applied, Roche, HemoCue and Abbott fulfilled the criterion in this patient population, whereas Nova and Menarini did not. However, when TNO quality guideline and NACB/ADA 2011 guideline were applied only Roche fulfilled the criteria.

Glucose meters: evaluation of the new formulation measuring strips from Roche (Accu-Chek) and Abbott (MediSense).

PubMed

Dimeski, G; Jones, B W; Tilley, V; Greenslade, M N; Russell, A W

2010-07-01

Both Roche and Abbott have released new glucose meter strips. They supply the entire Australian hospital market. The present study compared the performance of the new strips utilizing various specimen types (capillary, venous lithium heparin whole blood, venous lithium heparin plasma and serum) and evaluated how well they comply with the International Standards Organization (ISO) 15197 criteria. The study included imprecision, patient comparison and interference studies. Participants with and without diabetes were recruited to evaluate the performance of various specimen types against the Beckman DxC800 glucose method. The strips were tested for different interferences: galactose, maltose, lactose, Icodextrin, Intragam, paracetamol, sodium, ascorbic acid, variable strip storage temperature, haematocrit, haemolysis and lipaemia. The imprecision of the two strips was approximately 5% or less, except for the Abbott strip at very low values (1.4 mmol/L), approximately 7%. In total, 78% and 84%, respectively, of the results from the finger prick capillary specimens with the Roche (Accu-Chek Performa meter) and Abbott (Optium Xceed meter) strips, not 95% or greater as recommended by the ISO guideline, were within the recommended limits compared with reference plasma estimation on laboratory analysers. Galactose, ascorbic acid, haematocrit and sodium on the Roche and ascorbic acid and haematocrit on the Abbott strip continue to interfere to a variable degree with the glucose measurement. Analytically small differences exist between the glucose meter strips. The most significant analytical difference with the strips was at low glucose levels when compared with laboratory analyses and this may be of clinical importance. The impact of some of the interferences is variable between the two strips. Individuals, health-care professionals and health-care institutions should consider these data when selecting glucose meters for the management of people with diabetes mellitus.

TIDALLY DRIVEN ROCHE-LOBE OVERFLOW OF HOT JUPITERS WITH MESA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Valsecchi, Francesca; Rasio, Frederic A.; Rappaport, Saul

2015-11-10

Many exoplanets have now been detected in orbits with ultra-short periods very close to the Roche limit. Building upon our previous work, we study the possibility that mass loss through Roche lobe overflow (RLO) may affect the evolution of these planets, and could possibly transform a hot Jupiter into a lower-mass planet (hot Neptune or super-Earth). We focus here on systems in which the mass loss occurs slowly (“stable mass transfer” in the language of binary star evolution) and we compute their evolution in detail with the binary evolution code Modules for Experiments in Stellar Astrophysics. We include the effectsmore » of tides, RLO, irradiation, and photo-evaporation (PE) of the planet, as well as the stellar wind and magnetic braking. Our calculations all start with a hot Jupiter close to its Roche limit, in orbit around a Sun-like star. The initial orbital decay and onset of RLO are driven by tidal dissipation in the star. We confirm that such a system can indeed evolve to produce lower-mass planets in orbits of a few days. The RLO phase eventually ends and, depending on the details of the mass transfer and on the planetary core mass, the orbital period can remain around a few days for several Gyr. The remnant planets have rocky cores and some amount of envelope material, which is slowly removed via PE at a nearly constant orbital period; these have properties resembling many of the observed super-Earths and sub-Neptunes. For these remnant planets, we also predict an anti-correlation between mass and orbital period; very low-mass planets (M{sub pl} ≲ 5 M{sub ⊕}) in ultra-short periods (P{sub orb} < 1 day) cannot be produced through this type of evolution.« less

Tidal Barrier and the Asymptotic Mass of Proto-Gas Giant Planets

NASA Astrophysics Data System (ADS)

Dobbs-Dixon, Ian; Li, Shu Lin; Lin, D. N. C.

2007-05-01

According to the conventional sequential accretion scenario, observed extrasolar planets acquired their current masses via efficient gas accretion onto super-Earth cores with accretion timescales that rapidly increase with mass. Gas accretion in weak-line T Tauri disks may be quenched by global depletion of gas, but such a mechanism is unlikely to have stalled the growth in planetary systems that contain relatively low-mass, close-in planets together with more massive, longer period companions. Here, we suggest a potential solution for this conundrum. In general, supersonic infall of surrounding gas onto a protoplanet is only possible interior to both its Bondi and Roche radii. Above the critical mass where the Roche and Bondi radii are equal to the disk thickness, the protoplanet's tidal perturbation induces the formation of a gap. However, despite continued diffusion into the gap, the azimuthal flux across the protoplanet's Roche lobe will be quenched. Using two different schemes, we present the results of numerical simulations and analysis to show that the accretion rate increases rapidly with the ratio of the protoplanet's Roche to Bondi radii or equivalently to the disk thickness. Gas accretion is quenched, yielding relatively low protoplanetary masses, in regions with low aspect ratios. This becomes important for determining the gas giant planet's mass function, the distribution of their masses within multiple-planet systems, and for suppressing the emergence of gas giants around low-mass stars. Finally, we find that accretion rates onto protoplanets declines gradually on a characteristic timescale of a few Myr, during which the protracted accretion timescale onto circumplanetary disks may allow for the formation and retention of regular satellites.

Detection of Accretion X-Rays from QS Vir: Cataclysmic or a Lot of Hot Air?

NASA Astrophysics Data System (ADS)

Matranga, Marco; Drake, Jeremy J.; Kashyap, Vinay; Steeghs, Danny

2012-03-01

An XMM-Newton observation of the nearby "pre-cataclysmic" short-period (P orb = 3.62 hr) binary QS Vir (EC 13471-1258) revealed regular narrow X-ray eclipses when the white dwarf passed behind its M2-4 dwarf companion. The X-ray emission provides a clear signature of mass transfer and accretion onto the white dwarf. The low-resolution XMM-Newton EPIC spectra are consistent with a cooling flow model and indicate an accretion rate of \\dot{M} = 1.7 \\times 10^{-13} \\,M_\\odot yr-1. At 48 pc distant, QS Vir is then the second nearest accreting cataclysmic variable known, with one of the lowest accretion rates found to date for a non-magnetic system. To feed this accretion through a wind would require a wind mass-loss rate of \\dot{M}\\sim 2\\times 10^{-12}\\,M_\\odot yr-1 if the accretion efficiency is of the order of 10%. Consideration of likely mass-loss rates for M dwarfs suggests this is improbably high and pure wind accretion unlikely. A lack of accretion disk signatures also presents some difficulties for direct Roche lobe overflow. We speculate that QS Vir is on the verge of Roche lobe overflow, and that the observed mass transfer could be supplemented by upward chromospheric flows on the M dwarf, analogous to spicules and mottles on the Sun, that escape the Roche surface to be subsequently swept up into the white dwarf Roche lobe. If so, QS Vir would be in a rare evolutionary phase lasting only a million years. The X-ray luminosity of the M dwarf estimated during primary eclipse is LX = 3 × 1028 erg s-1, which is consistent with that of rapidly rotating "saturated" K and M dwarfs.

Exoplanet recycling in massive white-dwarf debris discs

NASA Astrophysics Data System (ADS)

Van Lieshout, Rik

2017-06-01

When a star evolves into a white dwarf, the planetary system it hosts can become unstable. Planets in such systems may then be scattered onto star-grazing orbits, leading to their tidal disruption as they pass within the white dwarf’s Roche limit. We study the massive, compact debris discs that may arrise from this process using a combination of analytical estimates and numerical modelling. The discs are gravitationally unstable, resulting in an enhanced effective viscosity due to angular momentum transport associated with self-gravity wakes. For disc masses greater than ~1026 g (corresponding to progenitor objects comparable to the Galilean moons), viscous spreading dominates over Poynting-Robertson drag in the outer parts of the disc. In such massive discs, mass is transported both in- and outwards. When the outward-flowing material spreads beyond the Roche limit, it coagulates into new (minor) planets in a process analogous to the ongoing formation of Saturn’s innermost moonlets. This process recycles a substantial fraction of the original disc mass (tens of percents), with the bulk of the mass locked in a single large body orbitting in a 2:1 mean-motion resonance with the Roche limit. As such, the recycling of a tidally disrupted super-Earth could yield an Earth-mass planet on a 10--20 hr orbit. For white dwarfs with a temperature below 6000-7000 K (corresponding to a cooling age of >1--2 Gyr), this orbit is located in the white dwarf’s habitable zone. The recycling process also creates a string of smaller bodies just outside the Roche limit. These may account for the collection of minor planets postulated to orbit white dwarf WD 1145+017.

Analysis of HbA1c on an automated multicapillary zone electrophoresis system.

PubMed

Rollborn, Niclas; Åkerfeldt, Torbjörn; Nordin, Gunnar; Xu, Xiao Yan; Mandic-Havelka, Aleksandra; Hansson, Lars-Olof; Larsson, Anders

2017-02-01

Hemoglobin A1c (HbA1c) is a frequently requested laboratory test and there is thus a need for high throughput instruments for this assay. We evaluated a new automated multicapillary zone electrophoresis instrument (Capillarys 3 Tera, Sebia, Lisses, France) for analysis of HbA1c in venous samples. Routine requested HbA1c samples were analyzed immunologically on a Roche c6000 instrument (n = 142) and then with the Capillarys 3 Tera instrument. The Capillarys 3 Tera instrument performed approximately 70 HbA1c tests/hour. There was a strong linear correlation between Capillarys 3 Tera and Roche Tina-Quant HbA1c Gen 3 assay (y = 1.003x - 0.3246 R 2  = .996). The total CV for the 12 capillaries varied between 0.8 and 2.2% and there was a good agreement between duplicate samples (R 2  = .997). In conclusion, the Capillarys 3 Tera instrument has a high assay capacity for HbA1c. It has a good precision and agreement with the Roche Tina-Quant HbA1c method and is well suited for high volume testing of HbA1c.

Validating urinary measurement of beta-2-microglobulin with a Roche reagent kit designed for serum measurements.

PubMed

Chan, Pak Cheung R; Kulasingam, Vathany; Lem-Ragosnig, Bonny

2012-11-01

To validate the use of a Roche serum beta-2-microglobulin (B2MG) kit for urinary B2MG measurements, and to establish reference limits for urinary B2MG/creatinine ratio from healthy individuals. The Roche B2MG Tina-Quant serum kit was used to measure urinary B2MG immunoturbidimetrically. Using human urine as a diluent, the B2MG method was linear from 73-2156 μg/L. The imprecision on a commercially available urine QC was 4.4% at a concentration of 380 μg/L. Limit of quantification at <20% CV was 40 μg/L. Method comparison with Immulite 2000 (Siemens) yielded slope=1.180 (95% CI 1.14-1.22), intercept=11.5 (95% CI -3.6-26.6), SEE=27.6 and r=0.99 (n=26) by the Deming regression analysis. The upper reference limit of B2MG/creatinine ratio determined from 195 healthy adults was 29 μg/mmol (97.5th centile). The serum B2MG Tina Quant reagent kit is acceptable to measure urinary B2MG. Copyright © 2012. Published by Elsevier Inc.

Image Dependent Relative Formation Navigation for Autonomous Aerial Refueling

DTIC Science & Technology

2011-03-01

and local variations of the Earth’s surface make a mathematical model difficult to create and use. The definition of an equipotential surface ...controlled with flight control surfaces attached to it. To refuel using this method, the receiver pilot flies the aircraft to within a defined refueling...I-frame would unnecessarily complicate aircraft navigation that, by definition, is limited to altitudes relatively close to the surface of the Earth

Viability of Using Diamond Field Emitter Array Cathodes in Free Electron Lasers

DTIC Science & Technology

2010-06-01

essential component of a field emitter array is the shape of the electric field lines and equipotential lines at the surface of the array. The...BARRIER AND QUANTUM TUNNELING ...........25 B. FIELD ENHANCEMENT AND SURFACE PROTRUSIONS .........26 C. ELECTRIC FIELDS AND ELECTRON TRAVEL...26 Figure 4. Diagram of a protrusion (triangular in shape) from the surface of a cathode. The protrusion is of height h, with a

Variational Data Assimilation for the Global Ocean

DTIC Science & Technology

2013-01-01

ocean includes the Geoid (a fixed gravity equipotential surface ) as well as the MDT, which is not known accurately enough relative to the centimeter...scales, including processes that control the surface mixed layer, the formation of ocean eddies, meandering ocean J.A. Cummings (E3) nography Division...variables. Examples of this in the ocean are integral quantities, such as acous^B travel time and altimeter measures of sea surface height, and direct

General technique for the integration of MIC/MMIC'S with waveguides

NASA Technical Reports Server (NTRS)

Geller, Bernard D. (Inventor); Zaghloul, Amir I. (Inventor)

1987-01-01

A technique for packaging and integrating of a microwave integrated circuit (MIC) or monolithic microwave integrated circuit (MMIC) with a waveguide uses a printed conductive circuit pattern on a dielectric substrate to transform impedance and mode of propagation between the MIC/MMIC and the waveguide. The virtually coplanar circuit pattern lies on an equipotential surface within the waveguide and therefore makes possible single or dual polarized mode structures.

Extraction electrode geometry for a calutron

DOEpatents

Veach, A.M.; Bell, W.A. Jr.

1975-09-23

This patent relates to an improved geometry for the extraction electrode and the ground electrode utilized in the operation of a calutron. The improved electrodes are constructed in a partial-picture-frame fashion with the slits of both electrodes formed by two tungsten elongated rods. Additional parallel spaced-apart rods in each electrode are used to establish equipotential surfaces over the rest of the front of the ion source. (auth)

High voltage variable diameter insulator

DOEpatents

Vanecek, David L.; Pike, Chester D.

1984-01-01

A high voltage feedthrough assembly (10) having a tubular insulator (15) extending between the ground plane ring (16) and the high voltage ring (30). The insulator (15) is made of Pyrex and decreases in diameter from the ground plane ring (16) to the high voltage ring (30), producing equipotential lines almost perpendicular to the wall (27) of the insulator (15) to optimize the voltage-holding capability of the feedthrough assembly (10).

Characterizing the Shape of Anatomical Structures With Poisson’s Equation

PubMed Central

Haidar, Haissam; Levitt, James J.; McCarley, Robert W.; Shenton, Martha E.; Soul, Janet S.

2009-01-01

Poisson’s equation, a fundamental partial differential equation in classical physics, has a number of properties that are interesting for shape analysis. In particular, the equipotential sets of the solution graph become smoother as the potential increases. We use the displacement map, the length of the streamlines formed by the gradient field of the solution, to measure the “complexity” (or smoothness) of the equipotential sets, and study its behavior as the potential increases. We believe that this function complexity = f (potential), which we call the shape characteristic, is a very natural way to express shape. Robust algorithms are presented to compute the solution to Poisson’s equation, the displacement map, and the shape characteristic. We first illustrate our technique on two-dimensional synthetic examples and natural silhouettes. We then perform two shape analysis studies on three-dimensional neuroanatomical data extracted from magnetic resonance (MR) images of the brain. In the first study, we investigate changes in the caudate nucleus in Schizotypal Personality Disorder (SPD) and confirm previously published results on this structure [1]. In the second study, we present a data set of caudate nuclei of premature infants with asymmetric white matter injury. Our method shows structural shape differences that volumetric measurements were unable to detect. PMID:17024829

Peripheral functional organisation of vagally evoked gastric motor responses in the ferret.

PubMed Central

Andrews, P L; Lawes, I N; Bower, A J

1980-01-01

The aims of the present study were to determine the relative amplitudes of intragastric motor responses evoked by different vagal branches and to establish whether the effects of acute or chronic vagotomy could be predicted from these data. Intragastric pressure responses to electrical stimulation of the vagus were measured in urethane-anaesthetised ferrets and acute or chronic vagotomies were performed. The results show that the left and right cervical vagi were equipotential and fully overlaped each other. Their contributions to the dorsal trunk were equipotential and fully overlapping and so were their contributions to the ventral trunk. The dorsal trunk was more effective than the ventral trunk and there was total functional overlap between these two trunks. Vagal evoked gastric motor responses of the ferret are apparently organised in a different way from vagally induced acid secretion or hormone release in the cat. Acute removal of a trunk led to a reduction in evoked responses that was not linear function of the effect of stimulation of that trunk. In contrast, chronic removal caused a relative increase in evoked responses that ws inversely related to the decrease caused by acute removal. The implications of total functional overlap and neuromuscular reorganisation after chronic vagotomy are discussed. PMID:7439800

Ice cream and orbifold Riemann-Roch

NASA Astrophysics Data System (ADS)

Buckley, Anita; Reid, Miles; Zhou, Shengtian

2013-06-01

We give an orbifold Riemann-Roch formula in closed form for the Hilbert series of a quasismooth polarized n-fold (X,D), under the assumption that X is projectively Gorenstein with only isolated orbifold points. Our formula is a sum of parts each of which is integral and Gorenstein symmetric of the same canonical weight; the orbifold parts are called ice cream functions. This form of the Hilbert series is particularly useful for computer algebra, and we illustrate it on examples of {K3} surfaces and Calabi-Yau 3-folds. These results apply also with higher dimensional orbifold strata (see [1] and [2]), although the precise statements are considerably trickier. We expect to return to this in future publications.

Roche tomography of cataclysmic variables - VIII. The irradiated and spotted dwarf nova, SS Cygni

NASA Astrophysics Data System (ADS)

Hill, C. A.; Smith, Robert Connon; Hebb, L.; Szkody, P.

2017-12-01

We present the results of our spectroscopic study of the dwarf nova SS Cyg, using Roche tomography to map the stellar surface and derive the system parameters. Given that this technique takes into account the inhomogeneous brightness distribution on the surface of the secondary star, our derived parameters are (in principle) the most robust yet found for this system. Furthermore, our surface maps reveal that the secondary star is highly spotted, with strongly asymmetric irradiation on the inner hemisphere. Moreover, by constructing Doppler tomograms of several Balmer emission lines, we find strong asymmetric emission from the irradiated secondary star, and an asymmetric accretion disc that exhibits spiral structures.

Plasmonic Roche lobe in metal-dielectric-metal structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shiu, Ruei-Cheng; Lan, Yung-Chiang

2013-07-15

This study investigates a plasmonic Roche lobe that is based on a metal-dielectric-metal (MDM) structure using finite-difference time-domain simulations and theoretical analyses. The effective refractive index of the MDM structure has two centers and is inversely proportional to the distance from the position of interest to the centers, in a manner that is analogous to the gravitational potential in a two-star system. The motion of surface plasmons (SPs) strongly depends on the ratio of permittivities at the two centers. The Lagrange point is an unstable equilibrium point for SPs that propagate in the system. After the SPs have passed throughmore » the Lagrange point, their spread drastically increases.« less

Tidal compression of a star by a large black hole. I Mechanical evolution and nuclear energy release by proton capture

NASA Astrophysics Data System (ADS)

Carter, B.; Luminet, J.-P.

1983-05-01

The gross qualitative behaviour of a star plunging deeply within the Roche tidal radius, RR, of a large black hole to a pericentre radius β-1RR, with β≳3, is examined using a simplified affine star model whose evolution is canonically determined by a Lagrangian formalism. In Phase I, for R≳RR, the star remains in only slightly distorted self-gravitating quasi-equilibrium, but in Phase II its particles undergo approximately free fall in the strong external tidal field within the Roche radius. In Phase III the compression is halted and reversed by the build-up of pressure in a highly flattened pancake configuration, in which adiabatic heating raises the temperature to a maximum given in most cases by Θm ≍ β-2Θ* where Θ* is the equilibrium core temperature. In Phase IV the matter expands again in approximately free fall, and in Phase V, as the star moves outside the Roche radius, pressure and self-gravitational forces again come into play. For stars rich in intermediate weight elements, nuclear energy release by proton capture in Phase III is shown to be important. Consideration of the more spectacular possibility of helium detonation is postponed until Part II.

Profile of the Roche cobas® EGFR mutation test v2 for non-small cell lung cancer.

PubMed

Malapelle, Umberto; Sirera, Rafael; Jantus-Lewintre, Eloísa; Reclusa, Pablo; Calabuig-Fariñas, Silvia; Blasco, Ana; Pisapia, Pasquale; Rolfo, Christian; Camps, Carlos

2017-03-01

The discovery of driver mutations in non-small cell lung cancer (NSCLC) has led to the development of genome-based personalized medicine. Fifteen to 20% of adenocarcinomas harbor an epidermal growth factor receptor (EGFR) activating mutation associated with responses to EGFR tyrosine kinase inhibitors (TKIs). Individual laboratories' expertise and the availability of appropriate equipment are valuable assets in predictive molecular pathology, although the choice of methods should be determined by the nature of the samples to be tested and whether the detection of only well-characterized EGFR mutations or rather, of all detectable mutations, is required. Areas covered: The EGFR mutation testing landscape is manifold and includes both screening and targeted methods, each with their own pros and cons. Here we review one of these companion tests, the Roche cobas® EGFR mutation test v2, from a methodological point of view, also exploring its liquid-biopsy applications. Expert commentary: The Roche cobas® EGFR mutation test v2, based on real time RT-PCR, is a reliable option for testing EGFR mutations in clinical practice, either using tissue-derived DNA or plasma-derived cfDNA. This application will be valuable for laboratories with whose purpose is purely diagnostic and lacking high-throughput technologies.

Mass-loss evolution of close-in exoplanets: Evaporation of hot Jupiters and the effect on population

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurokawa, H.; Nakamoto, T., E-mail: kurokawa@nagoya-u.jp

2014-03-01

During their evolution, short-period exoplanets may lose envelope mass through atmospheric escape owing to intense X-ray and extreme ultraviolet (XUV) radiation from their host stars. Roche-lobe overflow induced by orbital evolution or intense atmospheric escape can also contribute to mass loss. To study the effects of mass loss on inner planet populations, we calculate the evolution of hot Jupiters considering mass loss of their envelopes and thermal contraction. Mass loss is assumed to occur through XUV-driven atmospheric escape and the following Roche-lobe overflow. The runaway effect of mass loss results in a dichotomy of populations: hot Jupiters that retain theirmore » envelopes and super Earths whose envelopes are completely lost. Evolution primarily depends on the core masses of planets and only slightly on migration history. In hot Jupiters with small cores (≅ 10 Earth masses), runaway atmospheric escape followed by Roche-lobe overflow may create sub-Jupiter deserts, as observed in both mass and radius distributions of planetary populations. Comparing our results with formation scenarios and observed exoplanets populations, we propose that populations of closely orbiting exoplanets are formed by capturing planets at/inside the inner edges of protoplanetary disks and subsequent evaporation of sub-Jupiters.« less

Routine screening of blood donations at Qingdao central blood bank, China, for hepatitis B virus (HBV) DNA with a real-time, multiplex nucleic acid test for HBV, hepatitis C virus, and human immunodeficiency virus Types 1 and 2.

PubMed

Yang, Zhongsi; Xu, Lei; Liu, Li; Feng, Qiuxia; Zhang, Longmu; Ma, Weijuan; Saldanha, John; Wang, Mingmin; Zhao, Lin

2013-10-01

The Roche cobas TaqScreen MPX test was used to evaluate the rate of hepatitis B surface antigen (HBsAg)-negative donations that were hepatitis B virus (HBV) DNA reactive from June 2010 to January 2011 in Qingdao, China. HBsAg-negative samples from 65,800 voluntary blood donors were tested with the cobas TaqScreen MPX test in pools of 6 on the Roche cobas s 201 blood screening platform. Samples positive for HBV DNA and negative for HBsAg were quantitated with the Roche COBAS AmpliPrep/COBAS TaqMan HBV test. In addition, serologic tests for HBsAg, hepatitis B surface antibody, anti-hepatitis B core antigen (anti-HBc), anti-hepatitis B e antigen (anti-HBe), and hepatitis B e antigen (HBe) were done using the Roche electrochemiluminescence immunoassay. A total of 80 nucleic acid amplification technology (NAT) test-reactive pools were identified and 59 pools (74%) resolved to a reactive sample. All samples were HBV DNA reactive and the viral load in each sample was quantitated. The viral loads of the samples ranged from less than 20 to 34,600 IU/mL; 13 samples (22%) had viral loads of more than 20 IU/mL, 27 samples (45.8%) had viral loads of less than 20 IU/mL, and 19 samples (32.2%) had undetectable viral loads. Of the 59 NAT-reactive samples, 40 (67.8%) were anti-HBc positive. Fifteen of the 59 samples could not be confirmed as NAT reactive either by an alternative NAT test or by serology. The HBV NAT yield in blood donors in Qingdao is 0.06% (38/65,800). This study confirmed the value of NAT for interdicting HBV-positive donations and preventing transfusion-transmitted HBV infections. © 2013 American Association of Blood Banks.

Robe's restricted problem of 2+2 bodies when the bigger primary is a Roche ellipsoid and the smaller primary is an oblate body

NASA Astrophysics Data System (ADS)

Kaur, Bhavneet; Aggarwal, Rajiv

2014-01-01

In this problem, one of the primaries of mass m 1 is a Roche ellipsoid filled with a homogeneous incompressible fluid of density ρ 1. The smaller primary of mass m 2 is an oblate body outside the Ellipsoid. The third and the fourth bodies (of mass m 3 and m 4 respectively) are small solid spheres of density ρ 3 and ρ 4 respectively inside the Ellipsoid, with the assumption that the mass and the radius of the third and the fourth body are infinitesimal. We assume that m 2 is describing a circle around m 1. The masses m 3 and m 4 mutually attract each other, do not influence the motions of m 1 and m 2 but are influenced by them. We have extended the Robe's restricted three-body problem to 2+2 body problem under the assumption that the fluid body assumes the shape of the Roche ellipsoid (Chandrashekhar in Ellipsoidal figures of equilibrium, Chap. 8, Dover, New York, 1987). We have taken into consideration all the three components of the pressure field in deriving the expression for the buoyancy force viz (i) due to the own gravitational field of the fluid (ii) that originating in the attraction of m 2 (iii) that arising from the centrifugal force. In this paper, equilibrium solutions of m 3 and m 4 and their linear stability are analyzed. We have proved that there exist only six equilibrium solutions of the system, provided they lie within the Roche ellipsoid. In a system where the primaries are considered as Earth-Moon and m 3, m 4 as submarines, the equilibrium solutions of m 3 and m 4 respectively when the displacement is given in the direction of x 1-axis or x 2-axis are unstable.

Overview of Next-generation Sequencing Platforms Used in Published Draft Plant Genomes in Light of Genotypization of Immortelle Plant (Helichrysium Arenarium)

PubMed Central

Hodzic, Jasin; Gurbeta, Lejla; Omanovic-Miklicanin, Enisa; Badnjevic, Almir

2017-01-01

Introduction: Major advancements in DNA sequencing methods introduced in the first decade of the new millennium initiated a rapid expansion of sequencing studies, which yielded a tremendous amount of DNA sequence data, including whole sequenced genomes of various species, including plants. A set of novel sequencing platforms, often collectively named as “next-generation sequencing” (NGS) completely transformed the life sciences, by allowing extensive throughput, while greatly reducing the necessary time, labor and cost of any sequencing endeavor. Purpose: of this paper is to present an overview NGS platforms used to produce the current compendium of published draft genomes of various plants, namely the Roche/454, ABI/SOLiD, and Solexa/Illumina, and to determine the most frequently used platform for the whole genome sequencing of plants in light of genotypization of immortelle plant. Materials and methods: 45 papers were selected (with 47 presented plant genome draft sequences), and utilized sequencing techniques and NGS platforms (Roche/454, ABI/SOLiD and Illumina/Solexa) in selected papers were determined. Subsequently, frequency of usage of each platform or combination of platforms was calculated. Results: Illumina/Solexa platforms are by used either as sole sequencing tool in 40.42% of published genomes, or in combination with other platforms - additional 48.94% of published genomes, followed by Roche/454 platforms, used in combination with traditional Sanger sequencing method (10.64%), and never as a sole tool. ABI/SOLiD was only used in combination with Illumina/Solexa and Roche/454 in 4.25% of publications. Conclusions: Illumina/Solexa platforms are by far most preferred by researchers, most probably due to most affordable sequencing costs. Taking into consideration the current economic situation in the Balkans region, Illumina Solexa is the best (if not the only) platform choice if the sequencing of immortelle plant (Helichrysium arenarium) is to be performed by the researchers in this region. PMID:28974852

The future of discovery chemistry: quo vadis? Academic to industrial--the maturation of medicinal chemistry to chemical biology.

PubMed

Hoffmann, Torsten; Bishop, Cheryl

2010-04-01

At Roche, we set out to think about the future role of medicinal chemistry in drug discovery in a project involving both Roche internal stakeholders and external experts in drug discovery chemistry. To derive a coherent strategy, selected scientists were asked to take extreme positions and to derive two orthogonal strategic options: chemistry as the traditional mainstream science and chemistry as the central entrepreneurial science. We believe today's role of medicinal chemistry in industry has remained too narrow. To provide the innovation that industry requires, medicinal chemistry must play its part and diversify at pace with our increasing understanding of chemical biology and network pharmacology. 2010 Elsevier Ltd. All rights reserved.

Comparison of five methods for extraction of Legionella pneumophila from respiratory specimens.

PubMed

Wilson, Deborah; Yen-Lieberman, Belinda; Reischl, Udo; Warshawsky, Ilka; Procop, Gary W

2004-12-01

The efficiencies of five commercially available nucleic acid extraction methods were evaluated for the recovery of a standardized inoculum of Legionella pneumophila in respiratory specimens (sputum and bronchoalveolar lavage [BAL] specimens). The concentrations of Legionella DNA recovered from sputa with the automated MagNA Pure (526,200 CFU/ml) and NucliSens (171,800 CFU/ml) extractors were greater than those recovered with the manual methods (i.e., Roche High Pure kit [133,900 CFU/ml], QIAamp DNA Mini kit [46,380 CFU/ml], and ViralXpress kit [13,635 CFU/ml]). The rank order was the same for extracts from BAL specimens, except that for this specimen type the QIAamp DNA Mini kit recovered more than the Roche High Pure kit.

A Relation Between the Eikonal Equation Associated to a Potential Energy Surface and a Hyperbolic Wave Equation.

PubMed

Bofill, Josep Maria; Quapp, Wolfgang; Caballero, Marc

2012-12-11

The potential energy surface (PES) of a molecule can be decomposed into equipotential hypersurfaces. We show in this article that the hypersurfaces are the wave fronts of a certain hyperbolic partial differential equation, a wave equation. It is connected with the gradient lines, or the steepest descent, or the steepest ascent lines of the PES. The energy seen as a reaction coordinate plays the central role in this treatment.

Newton’s Rotating Water Bucket: A Simple Model

DTIC Science & Technology

2013-01-01

surface of the water must be an equipotential relative to the sum of the gravitational and centrifugal potential energies [9].) The value of z0 can be...twisted and the bucket is then released, it begins to spin and the surface of the water acquires a paraboloidal shape. In this paper, the parabolic...adopts a curved surface . Ernst Mach, for example, postulated that the parabolic shape must be due to the existence of matter in the universe

Analytical study of spheroidal dust grains in plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zahed, H.; Mahmoodi, J.; Sobhanian, S.

2006-05-15

Using the modified spheroidal equations, the potential of a spheroidal conducting grain, floated in a plasma, is calculated. The electric field and capacitance for both prolate and oblate spheroidal grains are investigated. The solutions, obtained up to the second-order approximation, show that the plasma screening causes the equipotential surfaces around the grain to be more elongated or flattened than the potential spheroids of the Laplace equation. This leads to the variation of the plasma concentration around the grain.

Timing of oceans on Mars from shoreline deformation.

PubMed

Citron, Robert I; Manga, Michael; Hemingway, Douglas J

2018-03-29

Widespread evidence points to the existence of an ancient Martian ocean. Most compelling are the putative ancient shorelines in the northern plains. However, these shorelines fail to follow an equipotential surface, and this has been used to challenge the notion that they formed via an early ocean and hence to question the existence of such an ocean. The shorelines' deviation from a constant elevation can be explained by true polar wander occurring after the formation of Tharsis, a volcanic province that dominates the gravity and topography of Mars. However, surface loading from the oceans can drive polar wander only if Tharsis formed far from the equator, and most evidence indicates that Tharsis formed near the equator, meaning that there is no current explanation for the shorelines' deviation from an equipotential that is consistent with our geophysical understanding of Mars. Here we show that variations in shoreline topography can be explained by deformation caused by the emplacement of Tharsis. We find that the shorelines must have formed before and during the emplacement of Tharsis, instead of afterwards, as previously assumed. Our results imply that oceans on Mars formed early, concurrent with the valley networks, and point to a close relationship between the evolution of oceans on Mars and the initiation and decline of Tharsis volcanism, with broad implications for the geology, hydrological cycle and climate of early Mars.

Evolutionary conservativeness of electric field in the Cu,Zn superoxide dismutase active site. Evidence for co-ordinated mutation of charged amino acid residues.

PubMed

Desideri, A; Falconi, M; Polticelli, F; Bolognesi, M; Djinovic, K; Rotilio, G

1992-01-05

Equipotential lines were calculated, using the Poisson-Boltzmann equation, for six Cu,Zn superoxide dismutases with different protein electric charge and various degrees of sequence homology, namely those from ox, pig, sheep, yeast, and the isoenzymes A and B from the amphibian Xenopus laevis. The three-dimensional structures of the porcine and ovine superoxide dismutases were obtained by molecular modelling reconstruction using the structure of the highly homologous bovine enzyme as a template. The three-dimensional structure of the evolutionary distant yeast Cu,Zn superoxide dismutase was recently resolved by us, while computer-modelled structures are available for X. laevis isoenzymes. The six proteins display large differences in the net protein charge and distribution of electrically charged surface residues but the trend of the equipotential lines in the proximity of the active sites was found to be constant in all cases. These results are in line with the very similar catlytic rate constants experimentally measured for the corresponding enzyme activities. This analysis shows that electrostatic guidance for the enzyme-substrate interaction in Cu,Zn superoxide dismutases is related to a spatial distribution of charges, arranged so as to maintain, in the area surrounding the active sites, an identical electrostatic potential distribution, which is conserved in the evolution of this protein family.

Spectral analysis of the gravity and topography of Mars

NASA Technical Reports Server (NTRS)

Bills, Bruce G.; Frey, Herbert V.; Kiefer, Walter S.; Nerem, R. Steven; Zuber, Maria T.

1993-01-01

New spherical harmonic models of the gravity and topography of Mars place important constraints on the structure and dynamics of the interior. The gravity and topography models are significantly phase coherent for harmonic degrees n less than 30 (wavelengths greater than 700 km). Loss of coherence below that wavelength is presumably due to inadequacies of the models, rather than a change in behavior of the planet. The gravity/topography admittance reveals two very different spectral domains: for n greater than 4, a simple Airy compensation model, with mean depth of 100 km, faithfully represents the observed pattern; for degrees 2 and 3, the effective compensation depths are 1400 and 550 km, respectively, strongly arguing for dynamic compensation at those wavelengths. The gravity model has been derived from a reanalysis of the tracking data for Mariner 9 and the Viking Orbiters, The topography model was derived by harmonic analysis of the USGS digital elevation model of Mars. Before comparing gravity and topography for internal structure inferences, we must ensure that both are consistently referenced to a hydrostatic datum. For the gravity, this involves removal of hydrostatic components of the even degree zonal coefficients. For the topography, it involves adding the degree 4 equipotential reference surface, to get spherically referenced values, and then subtracting the full degree 50 equipotential. Variance spectra and phase coherence of orthometric heights and gravity anomalies are addressed.

A new intracavitary probe for detecting the site of origin of ectopic ventricular beats during one cardiac cycle.

PubMed

Taccardi, B; Arisi, G; Macchi, E; Baruffi, S; Spaggiari, S

1987-01-01

An olive-shaped probe (25 X 12 mm) with 41 evenly distributed recording electrodes on its surface was introduced into the left ventricles of seven open-chest dogs via the left atrium. In two other dogs a cylindrical probe (40 X 3 mm) was used. Electrical stimuli were delivered at 66 endocardial, midwall, or epicardial sites in the left and right ventricular walls and the septum. Mechanical stimuli were also applied at various epicardial sites. On-line mapping of equipotential contour lines on the surface of the probe invariably revealed a clear-cut potential minimum on the electrode that faced the pacing site. Time of appearance of potential minimum was 3 to 5 msec after endocardial stimuli, 10 to 25 msec for midwall and epicardial pacing, and 30 msec or more for right ventricular stimulation. Simultaneous stimulation at two sites 1.2 cm apart gave rise to two separate minima on the maps. "Pseudoisochrones" derived from electrograms recorded by the new probe were slightly less accurate in indicating the site of origin of extrasystoles. We conclude that equipotential and "isochrone" contour maps recorded from an array of semidirect electrodes, regularly distributed on the surface of an intraventricular probe, provide information on the site of origin (location and intramural depth) of ectopic paced beats in a normal dog heart.

How does ice sheet loading affect ocean flow around Antarctica?

NASA Astrophysics Data System (ADS)

Dijkstra, H. A.; Rugenstein, M. A.; Stocchi, P.; von der Heydt, A. S.

2012-12-01

Interactions and dynamical feedbacks between ocean circulation, heat and atmospheric moisture transport, ice sheet evolution, and Glacial Isostatic Adjustment (GIA) are overlooked issues in paleoclimatology. Here we will present first results on how ocean flows were possibly affected by the glaciation of Antarctica across the Eocene-Oligocene Transition (~ 34 Ma) through GIA and bathymetry variations. GIA-induced gravitationally self-consistent bathymetry variations are determined by solving the Sea Level Equation (SLE), which describes the time dependent shape of (i) the solid Earth and (ii) the equipotential surface of gravity. Since the ocean circulation equations are defined relative to the equipotential surface of gravity, only bathymetry variations can influence ocean flows, although the sea surface slope will also change through time due to gravitational attraction. We use the Hallberg Isopycnal Model under late Eocene conditions to calculate equilibrium ocean flows in a domain in which the bathymetry evolves under ice loading according to the SLE. The bathymetric effects of the glaciation of Antarctica lead to substantial spatial changes in ocean flows, and close to the coast, the flow even reverses direction. Volume transports through the Drake Passage and Tasman Seaway adjust to the new bathymetry. The results indicate that GIA-induced ocean flow variations alone may have had an impact on sedimentation and erosion patterns, the repositioning of fronts, ocean heat transport and grounding line and ice sheet stability.

LUT observations of the mass-transferring binary AI Dra

NASA Astrophysics Data System (ADS)

Liao, Wenping; Qian, Shengbang; Li, Linjia; Zhou, Xiao; Zhao, Ergang; Liu, Nianping

2016-06-01

Complete UV band light curve of the eclipsing binary AI Dra was observed with the Lunar-based Ultraviolet Telescope (LUT) in October 2014. It is very useful to adopt this continuous and uninterrupted light curve to determine physical and orbital parameters of the binary system. Photometric solutions of the spot model are obtained by using the W-D (Wilson and Devinney) method. It is confirmed that AI Dra is a semi-detached binary with secondary component filling its critical Roche lobe, which indicates that a mass transfer from the secondary component to the primary one should happen. Orbital period analysis based on all available eclipse times suggests a secular period increase and two cyclic variations. The secular period increase was interpreted by mass transfer from the secondary component to the primary one at a rate of 4.12 ×10^{-8}M_{⊙}/yr, which is in agreement with the photometric solutions. Two cyclic oscillations were due to light travel-time effect (LTTE) via the presence of two cool stellar companions in a near 2:1 mean-motion resonance. Both photometric solutions and orbital period analysis confirm that AI Dra is a mass-transferring binary, the massive primary is filling 69 % of its critical Roche lobe. After the primary evolves to fill the critical Roche lobe, the mass transfer will be reversed and the binary will evolve into a contact configuration.

Quantification of Parvovirus B19 DNA Using COBAS AmpliPrep Automated Sample Preparation and LightCycler Real-Time PCR

PubMed Central

Schorling, Stefan; Schalasta, Gunnar; Enders, Gisela; Zauke, Michael

2004-01-01

The COBAS AmpliPrep instrument (Roche Diagnostics GmbH, D-68305 Mannheim, Germany) automates the entire sample preparation process of nucleic acid isolation from serum or plasma for polymerase chain reaction analysis. We report the analytical performance of the LightCycler Parvovirus B19 Quantification Kit (Roche Diagnostics) using nucleic acids isolated with the COBAS AmpliPrep instrument. Nucleic acids were extracted using the Total Nucleic Acid Isolation Kit (Roche Diagnostics) and amplified with the LightCycler Parvovirus B19 Quantification Kit. The kit combination processes 72 samples per 8-hour shift. The lower detection limit is 234 IU/ml at a 95% hit-rate, linear range approximately 104-1010 IU/ml, and overall precision 16 to 40%. Relative sensitivity and specificity in routine samples from pregnant women are 100% and 93%, respectively. Identification of a persistent parvovirus B19-infected individual by the polymerase chain reaction among 51 anti-parvovirus B19 IgM-negative samples underlines the importance of additional nucleic acid testing in pregnancy and its superiority to serology in identifying the risk of parvovirus B19 transmission via blood or blood products. Combination of the Total Nucleic Acid Isolation Kit on the COBAS AmpliPrep instrument with the LightCycler Parvovirus B19 Quantification Kit provides a reliable and time-saving tool for sensitive and accurate detection of parvovirus B19 DNA. PMID:14736825

Meticulous plasma isolation is essential to avoid false low-level viraemia in Roche Cobas HIV-1 viral load assays.

PubMed

Mortier, Virginie; Vancoillie, Leen; Dauwe, Kenny; Staelens, Delfien; Demecheleer, Els; Schauvliege, Marlies; Dinakis, Sylvie; Van Maerken, Tom; Dessilly, Géraldine; Ruelle, Jean; Verhofstede, Chris

2017-10-24

Pre-analytical sample processing is often overlooked as a potential cause of inaccurate assay results. Here we demonstrate how plasma, extracted from standard EDTA-containing blood collection tubes, may contain traces of blood cells consequently resulting in a false low-level HIV-1 viral load when using Roche Cobas HIV-1 assays. The presence of human DNA in Roche Cobas 4800 RNA extracts and in RNA extracts from the Abbott HIV-1 RealTime assay was assessed by quantifying the human albumin gene by means of quantitative PCR. RNA was extracted from plasma samples before and after an additional centrifugation and tested for viral load and DNA contamination. The relation between total DNA content and viral load was defined. Elevated concentrations of genomic DNA were detected in 28 out of 100 Cobas 4800 extracts and were significantly more frequent in samples processed outside of the AIDS Reference Laboratory. An association between genomic DNA presence and spurious low-level viraemia results was demonstrated. Supplementary centrifugation of plasma before RNA extraction eliminated the contamination and the false viraemia. Plasma isolated from standard EDTA-containing blood collection tubes may contain traces of HIV DNA leading to false viral load results above the clinical cutoff. Supplementary centrifugation of plasma before viral load analysis may eliminate the occurrence of this spurious low-level viraemia.

Electromagnetic Characterization of Carbon Nanotube Films Subject to an Oxidative Treatment at Elevated Temperature (Preprint)

DTIC Science & Technology

2010-07-01

response to the tip causes a redistribution of charge on the tip in order to maintain the equipotential surface of the sphere, and also results in a shift...can be obtained. In some instances these treatments lead to uncapping of nanotubes. Geng et al. [25] have shown that the surfaces of SWNT bundles...20] discovered a new and catalyst-free method for the growth of CNTs: surface decomposition of silicon carbide (SiC). This thermal decomposition

[Some aspects of animal-to-human approximation of low frequency electromagnetic field exposure conditions].

PubMed

Vasin, A L

2003-01-01

Appropriateness of representation of a biological object surface as an equipotential surface has been proved for conditions of a quasistatic exposure to EMF of frequencies lower than 1 MHz. The conditions, at which a self capacitance of a biological object is its basic electrical parameter, have been considered. A factor of animal-to-human approximation of low-frequency EMF exposure conditions was estimated on the basis of equal dose loading in biological objects of different geometric sizes.

Bodily Tides Near Spin-Orbit Resonances

DTIC Science & Technology

2012-01-01

radial term may cause an equipotential - surface variation of about 10 cm. This magnitude is large enough to be observed by future missions and should...U (r) = ∞∑ l=2 Ul(r) = ∞∑ l=2 kl ( R r )l+1 Wl(R, r∗), (2) R now being the mean equatorial radius of the primary, R = (R, φ, λ) being a surface point...rheology. For a homogeneous incompressible spherical primary of density ρ, surface gravity g, and rigidity μ, the static Love number of degree l is

[Method of recording impulses from an implanted cardiostimulator].

PubMed

Vetkin, A N; Osipov, V P

1976-01-01

An analysis of pulses from an implanted cardiostimulator recorded from the surface of the patient's body is one of the methods permitting it to pass judgment as to its functioning. Because of the possibility of the recording electrodes location coinciding with the equipotential line an erroneous interpretation of the cardiostimulator's condition is not to be ruled out. It is recommended that the pulses should be recorded with their subsequent analysis in no less than 2 standard ECG leads from the limbs.

Measurement of gastrointestinal transmural electric potential difference in man.

PubMed

Geall, M G; Code, C F; McIlrath, D C; Summerskill, W H

1970-01-01

Measurement, in man, of the electric potential difference between venous blood and the mucosal surface of the gastrointestinal tract gave identical values to the potential difference between mucosa and serosa. Various parts of the peritoneum were equipotential with venous blood. By contrast, skin-enteric potential difference varied with time and among different subjects because of a potential difference between skin and blood that is unpredictably reduced by skin injury. The results with electrolyte bridges of KCl in agar or of flowing KCl were identical.

Asymmetric ion trap

DOEpatents

Barlow, Stephan E.; Alexander, Michael L.; Follansbee, James C.

1997-01-01

An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity.

Reverse Algols

NASA Technical Reports Server (NTRS)

Leung, K. C.

1989-01-01

Reverse Algols, binary systems with a semidetached configuration in which the more massive component is in contact with the critical equipotential surface, are examined. Observational evidence for reverse Algols is presented and the parameters of seven reverse Algols are listed. The evolution of Algols and reverse Algols is discussed. It is suggested that, because reverse Algols represent the premass-reversal semidetached phase of close binary evolution, the evolutionary time scale between regular and reverse Algols is the ratio of the number of confirmed systems of these two Algol types.

Measurement of gastrointestinal transmural electric potential difference in man

PubMed Central

Geall, Michael G.; Code, Charles F.; McIlrath, Donald C.; Summerskill, W. H. J.

1970-01-01

Measurement, in man, of the electric potential difference between venous blood and the mucosal surface of the gastrointestinal tract gave identical values to the potential difference between mucosa and serosa. Various parts of the peritoneum were equipotential with venous blood. By contrast, skin-enteric potential difference varied with time and among different subjects because of a potential difference between skin and blood that is unpredictably reduced by skin injury. The results with electrolyte bridges of KCl in agar or of flowing KCl were identical. PMID:5435266

Partitioning of Electromagnetic Energy Inputs to the Thermosphere during Geomagnetic Disturbances

DTIC Science & Technology

2012-06-01

boundary of a local flux tube volume is an equipotential . Figure 4 contains maps of Poynting flux normal to a 500 km altitude surface and maps of height...as a cell quantity throughout its computational volume, we are able to generate maps of the Poynting flux, ⃗ ⃗⃗⃗⃗⃗⃗ , on altitude surfaces at...the top of the thermosphere. We used separate modules to integrate the Poynting flux over this surface to compute the total electromagnetic energy

Plasma and Electro-energetic Physics

DTIC Science & Technology

2012-03-07

Dynamical Equations (with complex surfaces ): Relativistic Lorentz Force Law for relativistic momentum p and velocity u: tDcJcH tBcE   /)/1()/4...0.1-1 s • 3D, high-fidelity, parallel modeling of high energy density fields and particles in complex geometry with some surface effects...cathodes (500 µm separation) Tang, AFRL/RD 12 DISTRIBUTION A: Approved for public release; distribution is unlimited. ICEPIC simulations Equipotential

Multifunctional Carbon Nanotube-Based Sensors for Damage Detection and Self Healing in Structural Composites

DTIC Science & Technology

2010-10-29

established based on the concept of equipotential surface . The effect of nanotube length on the critical charge level is plotted in Fig. 17. Fig...walled carbon nanotubes was used to develop composites with agglomerated regions of nanotubes at the fiber surface [3]. An image of the nanotube...coating on the surface of two E-glass fibers is shown in Fig. 5. Fig. 5. (a) Carbon nanotube agglomerates on the surface of glass fibers in the

Arctic Sea Ice: Using Airborne Topographic Mapper Measurements (ATM) to Determine Sea Ice Thickness

DTIC Science & Technology

2011-05-10

Track Distance (Km) E le v a ti o n ( m ) ATM Elevation Profile Elevation 18 Figure 13: Geoid shape of earth’s equipotential surface , which is...inferred for the region between successive leads. Therefore, flying over a lead in the ice is very important for determining the exact sea surface elevation...inferred for the region between successive leads. Therefore, flying over a lead in the ice is very important for determining the exact sea surface

Modeling of Electrochemical Copying in a Finite-Width Cell

NASA Astrophysics Data System (ADS)

Zhitnikov, V. P.; Sherykhalina, N. M.; Zaripov, A. A.

2017-11-01

The problem of modeling of electrochemical machining is reduced to the solution of the Schwartz problem on a parametrical rectangle with the use of theta-functions. Various conditions (non-equipotentiality of electrodes and inconstancy of current efficiency) at the boundary of a processed surface are considered. Nonstationary, quasistationary, stationary, and limit solutions are studied. Results of machining of surfaces by tool electrodes of various shapes are given. It is shown that machining mode parameters significantly affect the dissolved layer size necessary for obtaining high-precision copying.

Monterey Bay Geoid

DTIC Science & Technology

1994-03-01

thought to be a flat disk. The first scientific hypothesis that the earth was spherical is credited to Thales of Milet in 600 B.C. or Pythagoras in 550...acceleration can be integrated over the surface, by Gauss’s theorem and gives: 35 v1 Wv2 <v3 Figure 12. Equipotential Surfaces and Gravity: V,, V2, V3 are...continuous derivatives where they satisfy Laplace’s equation. Stokes’ theorem states that a harmonic function outside a surface is uniquely determined by

[G-CSF (Neupogen Roche) in the treatment of patients with chronic aplastic anemia with severe neutropenia].

PubMed

Novotný, J; Zvarová, M; Prazáková, L; Jandlová, M; Konvicková, L

1995-10-01

Aplastic anaemia (AA) of the chronic type with severe cytopenia is very frequently a difficult therapeutic problem. Patients with granulocyte values below 0.5 G/l are threatened by infections, incl. sepsis possibly with a fatal outcome. If the pool of stem cells for granulocytes is not completely exhausted and can respond to growth factors, these patients can be treated either chronically and/or in risk situations (e.g. injury, surgery) with preparations of the type of a recombinant, granulocyte colony stimulating factor (rhG-CSF), or granulocyte and monocyte colony stimulating factor (rhGM-CSF). The authors present a review of diagnostic and therapeutic algorithms in patients with the AA syndrome and summarize their own experience with the preparation Neupogen Roche (rhG-CSF).

A PIONIER and Incisive Look at the Interacting Binary SS Lep

NASA Astrophysics Data System (ADS)

Blind, N.; Boffin, H. M. J.; Berger, J.-P.; Lebouquin, J.-B.; Mérand, A.

2011-09-01

Symbiotic stars are excellent laboratories to study a broad range of poorly understood physical processes, such as mass loss of red giants, accretion onto compact objects, and evolution of nova-like outbursts. As their evolution is strongly influenced by the mass transfer episodes, understanding the history of these systems requires foremost to determine which process is at play: Roche lobe overflow, stellar wind accretion, or some more complex mixture of both. We report here an interferometric study of the symbiotic system SS Leporis, performed with the unique PIONIER instrument. By determining the binary orbit and revisiting the parameters of the two stars, we show that the giant does not fill its Roche lobe, and that the mass transfer most likely occurs via the accretion of an important part of the giant's wind.

Presidential Green Chemistry Challenge: 2000 Greener Synthetic Pathways Award

EPA Pesticide Factsheets

Presidential Green Chemistry Challenge 2000 award winner, Roche Colorado, developed a greener synthesis for gancyclovir (Cytovene, a potent antiviral drug) that uses a second-generation Guanine Triester (GTE) process.

Little Tuber Moon

NASA Image and Video Library

2010-01-05

Saturn small moon Prometheus, slightly overexposed in this image taken by NASA Cassini spacecraft, shows off its potato-like shape as it orbits in the Roche Division between the A ring and thin F ring.

Laboratory Evaluation of the Liat HIV Quant (IQuum) Whole-Blood and Plasma HIV-1 Viral Load Assays for Point-of-Care Testing in South Africa

PubMed Central

Gous, Natasha; Carmona, Sergio; Stevens, Wendy

2015-01-01

Point-of-care (POC) HIV viral load (VL) testing offers the potential to reduce turnaround times for antiretroviral therapy monitoring, offer near-patient acute HIV diagnosis in adults, extend existing centralized VL services, screen women in labor, and prompt pediatrics to early treatment. The Liat HIV Quant plasma and whole-blood assays, prerelease version, were evaluated in South Africa. The precision, accuracy, linearity, and agreement of the Liat HIV Quant whole-blood and plasma assays were compared to those of reference technologies (Roche CAP CTMv2.0 and Abbott RealTime HIV-1) on an HIV verification plasma panel (n = 42) and HIV clinical specimens (n = 163). HIV Quant plasma assay showed good performance, with a 2.7% similarity coefficient of variation (CV) compared to the Abbott assay and a 1.8% similarity CV compared to the Roche test on the verification panel, and 100% specificity. HIV Quant plasma had substantial agreement (pc [concordance correlation] = 0.96) with Roche on clinical specimens and increased variability (pc = 0.73) in the range of <3.0 log copies/ml range with the HIV Quant whole-blood assay. HIV Quant plasma assay had good linearity (2.0 to 5.0 log copies/ml; R2 = 0.99). Clinical sensitivity at a viral load of 1,000 copies/ml of the HIV Quant plasma and whole-blood assays compared to that of the Roche assay (n = 94) was 100% (confidence interval [CI], 95.3% to 100%). The specificity of HIV Quant plasma was 88.2% (CI, 63.6% to 98.5%), and that for whole blood was 41.2% (CI, 18.4% to 67.1%). No virological failure (downward misclassification) was missed. Liat HIV Quant plasma assay can be interchanged with existing VL technology in South Africa. Liat HIV Quant whole-blood assay would be advantageous for POC early infant diagnosis at birth and adult adherence monitoring and needs to be evaluated further in this clinical context. LIAT cartridges currently require cold storage, but the technology is user-friendly and robust. Clinical cost and implementation modeling is required. PMID:25740777

Skin Microbiome in Patients With Psoriasis Before and After Balneotherapy at the Thermal Care Center of La Roche-Posay.

PubMed

Martin, Richard; Henley, Jessica B; Sarrazin, Patrick; Seité, Sophie

2015-12-01

Changes in the composition of microbial communities that colonize skin have been linked to several diseases including psoriasis. Nevertheless, the intra-individual dynamics and how these communities respond to balneotherapy remain poorly understood. This open label study was conducted between July and September 2012. Microbial communities of patients with psoriasis vulgaris were characterized prior and post a 3-week selenium-rich water balneotherapy treatment at the thermal care center La Roche-Posay (La Roche-Posay, France). Balneotherapy consisted of high-pressure filiform showers, baths, facial, and body spray treatments as well as La Roche-Posay thermal spring water (LRP-TSW) consumption. Swabs were taken from affected and proximal unaffected skin and the 16S rRNA bacterial gene was used to analyze the composition of bacterial communities. Using the same 16S rRNA gene tool, we tried to describe the LRP-TSW bacterial landscape. This study included 54 patients diagnosed with moderate to severe forms of psoriasis vulgaris. After eliminating individuals lacking paired samples from both visits, 29 individuals were analyzed for their microbiome profile. Shannon Diversity Index and global bacterial landscape indicate similar microbial communities on both unaffected and adjacent affected skin. PASI values decreased post-balneotherapy implying improvement of disease severity. No significant change in the Shannon Diversity Index was noticed at the end of the third week. The average taxonomic composition of skin microbial communities associated with unaffected and affected skin of psoriatic patients post-balneotherapy shows that treatment with LRP-TSW significantly increased the level of Xanthomonas genus and, to a lesser extent, Corynebacterium genus. The Xanthomonas genus belongs to the main Xanthomonadaceae family found in LRP-TSW and also on healthy skin. In psoriatic patients, a poor bacterial biodiversity was noticed and the bacterial communities were similar on unaffected and affected adjacent skin. Family analysis identified, for the first time, Xanthomonadaceae belonging to Proteobacteria phylum and known to be keratolytic, associated with the clinical improvement observed after a 3-week balneotherapy treatment. This data supports the interest of selenium-rich thermal spring water in the treatment of psoriasis vulgaris.

Conduction velocity of action potentials measured from unidimensional latency-topography in human and frog skeletal muscle fibers.

PubMed

Homma, S; Nakajima, Y; Hayashi, K; Toma, S

1986-01-01

Conduction of an action potential along skeletal muscle fibers was graphically displayed by unidimensional latency-topography, UDLT. Since the slopes of the equipotential line were linear and the width of the line was constant, it was possible to calculate conduction velocity from the slope. To determine conduction direction of the muscle action potential elicited by electric stimulation applied directly to the muscle, surface recording electrodes were placed on a two-dimensional plane over a human muscle. Thus a bi-dimensional topography was obtained. Then, twelve or sixteen surface electrodes were placed linearly along the longitudinal direction of the action potential conduction which was disclosed by the bi-dimensional topography. Thus conduction velocity of muscle action potential in man, calculated from the slope, was for m. brachioradialis, 3.9 +/- 0.4 m/s; for m. biceps brachii, 3.6 +/- 0.2 m/s; for m. sternocleidomastoideus, 3.6 +/- 0.4 m/s. By using a tungsten microelectrode to stimulate the motor axons, a convex-like equipotential line of an action potential in UDLT was obtained from human muscle fibers. Since a similar pattern of UDLT was obtained from experiments on isolated frog muscles, in which the muscle action potential was elicited by stimulating the motor axon, it was assumed that the maximum of the curve corresponds to the end-plate region, and that the slopes on both sides indicate bi-directional conduction of the action potential.

Inferences About the Early Moon from Gravity and Topography

NASA Technical Reports Server (NTRS)

Smith, David E.; Zuber, Maria T.

1998-01-01

Recent spacecraft missions to the Moon have significantly improved our knowledge of the lunar gravity and topography fields and have raised some new and old questions about the early lunar history. It has frequently been assumed that the shape of the Moon today reflects an earlier equilibrium state and that the Moon has retained some internal strength. Recent analysis indicating a superisostatic state of some lunar basins lends support to this hypothesis. On its simplest level the present shape of the Moon is slightly flattened by 2.2 +/- 0.2 km while its gravity field, represented by an equipotential surface, is flattened only about 0.5 km. The hydrostatic component to the flattening arising from the Moon's present-day rotation contributes only 7 m. This difference between the topographic shape of the Moon and the shape of its gravitational equipotential has frequently been explained as the "memory" of an earlier Moon that was rotating faster and had a correspondingly larger hydrostatic flattening. To obtain this amount of hydrostatic flattening from rotation alone, and accounting for the contribution of the present-day gravity field, the Moon's rotation rate would need to be about 15 times greater than at present leading to a period of under 2 days. Maintaining its synchronous rotation with Earth would require a radius for the Moon's orbit of order 9 earth radii. Unfortunately, our confidence in the observed lunar flattening is not as great as we would like.

Electrical Mapping of Silver Nanowire Networks: A Versatile Tool for Imaging Network Homogeneity and Degradation Dynamics during Failure.

PubMed

Sannicolo, Thomas; Charvin, Nicolas; Flandin, Lionel; Kraus, Silas; Papanastasiou, Dorina T; Celle, Caroline; Simonato, Jean-Pierre; Muñoz-Rojas, David; Jiménez, Carmen; Bellet, Daniel

2018-05-22

Electrical stability and homogeneity of silver nanowire (AgNW) networks are critical assets for increasing their robustness and reliability when integrated as transparent electrodes in devices. Our ability to distinguish defects, inhomogeneities, or inactive areas at the scale of the entire network is therefore a critical issue. We propose one-probe electrical mapping (1P-mapping) as a specific simple tool to study the electrical distribution in these discrete structures. 1P-mapping has allowed us to show that the tortuosity of the voltage equipotential lines of AgNW networks under bias decreases with increasing network density, leading to a better electrical homogeneity. The impact of the network fabrication technique on the electrical homogeneity of the resulting electrode has also been investigated. Then, by combining 1P-mapping with electrical resistance measurements and IR thermography, we propose a comprehensive analysis of the evolution of the electrical distribution in AgNW networks when subjected to increasing voltage stresses. We show that AgNW networks experience three distinctive stages: optimization, degradation, and breakdown. We also demonstrate that the failure dynamics of AgNW networks at high voltages occurs through a highly correlated and spatially localized mechanism. In particular the in situ formation of cracks could be clearly visualized. It consists of two steps: creation of a crack followed by propagation nearly parallel to the equipotential lines. Finally, we show that current can dynamically redistribute during failure, by following partially damaged secondary pathways through the crack.

On the Evolution of Low-Mass X-Ray Binaries under the Influence of a Donor Stellar Wind Induced by X-Rays from the Accretor

NASA Astrophysics Data System (ADS)

Iben, Icko, Jr.; Tutukov, Alexander V.; Fedorova, Alexandra V.

1997-09-01

In a low-mass X-ray binary (LMXB), an intense stellar wind from the mass donor may be a consequence of the absorption of X-rays from the mass-accreting neutron star or black hole, and such a wind could change the evolution of these binaries dramatically compared with the evolution of cataclysmic variables (CVs), which are close binaries in which the accretor is a white dwarf. An analytical study and numerical models show that, in the closest and brightest LMXBs, a relativistic companion can capture up to ~10% of the mass lost in the induced stellar wind (ISW) from the main-sequence or subgiant donor, and this is enough to keep the X-ray luminosity of a typical LMXB on the level of LX ~ 5000 L⊙ and to accelerate the rotation of an old neutron star with a low magnetic field into the millisecond-period range. A self-sustained ISW may exist even if the donor does not fill its Roche lobe, but the system can be bright (LX > 100 L⊙) only if the radius of the donor is a substantial fraction (>~0.8) of the Roche lobe radius. A lower limit on the Roche lobe filling factor follows from the circumstance that both the rate Ėwind at which work must be done to lift wind matter off the donor and the rate Ėabs at which the donor absorbs X-ray energy are proportional to ṀISW (the ISW mass-loss rate) and from the requirement that Ėwind<Ėabs in order for energy to be conserved. The observed number (~100) of bright LMXBs in our Galaxy can be understood as the product of a relatively short lifetime (a few × 107 yr) and a small theoretical birthrate (~2 × 10-6-8 × 10-6 yr-1), which is comparable to semiempirical estimates of the birthrate of LMXBs and millisecond pulsars (~2 × 10-6 yr-1). The theoretical lifetime is ~10-60 times shorter than when the ISW is not taken into account, and the theoretical birthrate is ~3-6 times smaller, because of the fact that the ISW acts to expand the orbit and reduce the number of systems that can evolve through an X-ray bright stage under the influence of a magnetic stellar wind (MSW) when the donor is a main-sequence star (CV-like LMXBs), or under the influence of nuclear evolution when the donor is a subgiant or giant with a degenerate helium core (Algol-like LMXBs) of mass in the range MHe = 0.13-0.45 M⊙. The observed concentration of LMXBs in the 3-24 hr orbital period range corresponds to a similar concentration in the CV distribution and could be interpreted as evidence that the MSW in LMXBs operates at a strength not too different from its strength in CVs. For 0.3-1 M⊙ main-sequence donors, if the radius of the donor is larger than ~70% of the Roche lobe radius, the tendency of the ISW to force orbital expansion can balance the braking influence of the MSW and prevent an LMXB with a main-sequence donor from evolving to periods less than ~3 hr. When a main-sequence donor becomes completely convective (donor mass ~0.1-0.3 M⊙, depending on the mass-loss rate) and the MSW shuts off, orbital angular momentum loss due to gravitational wave radiation (GWR) is unable to counter the tendency toward expansion, and this may explain the apparent absence of short-period (Porb < 3 hr) LMXBs with main-sequence donors. This contrasts with the CV family in which the number of systems in the Galaxy with Porb ~ 1.3-2 hr (with donor mass <=0.3 M⊙ and with evolution driven only by GWR) is larger by a factor of ~100 than the number of systems with Porb > 3 hr. In Algol-like LMXBs in the Galactic disk, the timescale for the evaporation (caused by the ISW) of the donor with a low-mass, degenerate helium core can be smaller than the timescale for the radial expansion of the donor owing to nuclear evolution, and the donor may never fill its Roche lobe. However, if progenitor binaries are initially wide enough, the donor may escape evaporation as a main-sequence star, and significant mass transfer may not occur until the secondary evolves into a giant with a degenerate helium core of large mass and fills its Roche lobe. In globular clusters, as a result of capture and exchange reactions, semidetached Algol-like LMXBs can be formed in which the donor can fill its Roche lobe even when its degenerate helium core is of small mass, and Roche lobe mediated mass transfer driven by the nuclear evolution of the donor can dominate over capture from the ISW. The numerical models formally imply the possible presence in the Galaxy of ~104 dim (LX ~ 1-100 L⊙), long-period LMXBs or radio pulsars with low-mass (~0.05 M⊙) companions. Since there are few, if any, known observational counterparts of these systems, it is necessary to invoke a mechanism or mechanisms to destroy their formal progenitors. Possible destruction mechanisms include: (1) evaporation driven by the radiation from the rapidly rotating pulsar into which the accretor has been transformed by accretion during the bright LMXB phase, and (2) a dynamical instability arising when the donor is almost completely convective and fills its Roche lobe. In the case of dynamical disruption, the donor may be transformed into the envelope of a Thorne-Żytkow (1975) object with a neutron star or black hole core or into a planet-forming disk around the neutron star or black hole. A few short-period (Porb < 3 hr) LMXBs do exist, and, in them, the donor may be a helium white dwarf of mass less than ~0.09 M⊙. An ISW operating before the donor fills its Roche lobe may be responsible for reducing the mass of the white dwarf from an initial value of >=0.13 M⊙ to a value of <=0.09 M⊙, thus permitting stable mass exchange (at a rate smaller than the Eddington limiting rate) and evolution to longer periods to occur after the donor fills its Roche lobe. Another scenario relies on the collapse of a massive oxygen-neon white dwarf, which has accreted from a Roche lobe filling helium white dwarf. Problems that must be explored further in order to acquire a better understanding of the evolution of LMXBs include the formation of a corona around an irradiated low-mass main-sequence or degenerate dwarf star, accretion of ISW matter by a neutron star or black hole companion, the effect of an ISW on the MSW, formation of millisecond pulsars, complete evaporation of low-mass donors, disruption by tidal forces of a low-mass main-sequence star or a degenerate dwarf companion into a gas disk around the accretor, and the formation of planetary systems in the disk around neutron stars and or black holes in post-LMXB systems. Supported in part by the NSF (US) grant AST 94-17156 and the Russian Fund for Fundamental Research.

Studies in matter antimatter separation and in the origin of lunar magnetism

NASA Technical Reports Server (NTRS)

Barker, W. A.; Greeley, R.; Parkin, C.; Aggarwal, H.

1974-01-01

Antimatter experiments of the University of Santa Clara are investigated. Topics reported include: (1) planetary geology, (2) lunar Apollo magnetometer experiments, and (3) Roche limit of a solid body.

Duplex detection of the Mycobacterium tuberculosis complex and medically important non-tuberculosis mycobacteria by real-time PCR based on the rnpB gene.

PubMed

Abdeldaim, Guma; Svensson, Erik; Blomberg, Jonas; Herrmann, Björn

2016-11-01

A duplex real-time PCR based on the rnpB gene was developed for Mycobacterium spp. The assay was specific for the Mycobacterium tuberculosis complex (MTB) and also detected all 19 tested species of non-tuberculous mycobacteria (NTM). The assay was evaluated on 404 clinical samples: 290 respiratory samples and 114 from tissue and other non-respiratory body sites. M. tuberculosis was detected by culture in 40 samples and in 30 samples by the assay. The MTB assay showed a sensitivity similar to Roche Cobas Amplicor MTB-PCR (Roche Molecular Systems, Pleasanton, CA, USA). There were only nine samples with non-tuberculous mycobacteria detected by culture. Six of them were detected by the PCR assay. © 2016 APMIS. Published by John Wiley & Sons Ltd.

Clinical evaluation of cobas core anti-dsDNA EIA quant.

PubMed

González, Concepción; Guevara, Paloma; García-Berrocal, Belén; Alejandro Navajo, José; Manuel González-Buitrago, José

2004-01-01

The measurement of antibodies to double-stranded DNA (anti-dsDNA) is a useful tool for the diagnosis and monitoring of patients with connective tissue diseases, particularly systemic lupus erythematosus (SLE). The aim of the present study was to compare a new enzyme-linked immunosorbent assay (ELISA) for the measurement of anti-dsDNA antibodies, which uses purified double-stranded plasmid DNA as the antigen (anti-dsDNA EIA Quant; Roche Diagnostics, Mannheim, Germany), with an established ELISA. The clinical usefulness of this new ELISA was also assessed. We measured anti-dsDNA antibodies in 398 serum samples that were divided into four groups: 1). routine samples sent to our laboratory for an antinuclear antibody (ANA) test (n=229), 2). samples from blood donors (n=74), 3). samples from patients with SLE (n=48), and 4) samples from patients with other autoimmune diseases (n=47). The methods used were the Cobas Core Anti-dsDNA EIA Quant (Roche Diagnostics, Mannheim, Germany) and the Anti-dsDNA test (Gull Diagnostics, Bois d'Arcy, France). We obtained a kappa index and Spearman correlation coefficient in the comparative study, and sensitivity, specificity, predictive values, and likelihood ratios in the clinical study. The results obtained show a good agreement between the two methods in both the qualitative results (kappa=0.91) and the quantitative data (r=0.854). The best accuracy, predictive values, likelihood ratios, and correlation with active disease were obtained with the Roche anti-dsDNA assay. Copyright 2004 Wiley-Liss, Inc.

[Development and application of CK-MB specific monoclonal antibodies].

PubMed

Chen, Zimin; Zhou, Guoliang; Xu, Weiling; Zheng, Xiaohong; Tong, Xunzhang; Ke, Qishen; Song, Liuwei; Ge, Shengxiang

2017-01-25

The aim of this study is to develop creatine kinase isoenzyme MB (CK-MB) specific monoclonal antibodies (mAb), and characterize the monoclonal antibody and further development of quantitative detection assay for CK-MB. The BALB/c mice were immunized with purchased CK-MB antigen, then monoclonal antibodies were prepared according to conventional hybridoma technique and screened by indirect and capture ELISA method. To identify the epitopes and evaluate the classification, purchased creatine kinase isoenzyme MB (CK-MM/BB/MB) antigen was used to identify the epitopes, with immunoblotting and synthetic CK-MM and CK-BB in different linear epitope. A double antibody sandwich ELISA was applied to screen the mAb pairs for CK-MB detection, and the quantitative detection assay for CK-MB was developed. We used 74 cases of clinical specimens for comparison of our assay with Roche's CK-MB assay. We successfully developed 22 strains of hybridoms against CK-MB, these mAbs can be divided into linear, partial conformational CK-MB, CK-MM or CK-BB cross monoclonal antibody and CK-MB specific reaction with partial conformational monoclonal antibody, and CK-MB quantitative detection assay was developed by using partial conformational monoclonal antibody. The correlation coefficient factor r of our reagent and Roche's was 0.930 9. This study established a screening method for CK-MB partial conformational specific monoclonal antibody, and these monoclonal antibodies were analyzed and an established quantitative detection assay was developed. The new assay had a high concordance with Roche's.

CCD Photometry and Roche Modeling of the Eclipsing Deep Low Mass, Overcontact Binary Star System TYC 2058-753-1

NASA Astrophysics Data System (ADS)

Alton, K. B.

2018-06-01

Abstract TYC 2058-753-1 (NSVS 7903497; ASAS 165139+2255.7) is a W UMa binary system (P = 0.353205 d) which has not been rigorously studied since first being detected nearly 15 years ago by the ROTSE-I telescope. Other than the unfiltered ROTSE-I and monochromatic All Sky Automated Survey (ASAS) survey data, no multi-colored light curves (LC) have been published. Photometric data collected in three bandpasses (B, V, and Ic) at Desert Bloom Observatory in June 2017 produced six times-of-minimum for TYC 2058-753-1 which were used to establish a linear ephemeris from the first directly measured Min I epoch (HJD0). No published radial velocity data are available for this system, however, since this W UMa binary undergoes a very obvious total eclipse, Roche modeling produced a well-constrained photometric value for the mass ratio (qph = 0.103 ± 0.001). This low-mass ratio binary star system also exhibits a high degree of contact (f > 56%). There is a suggestion from the ROTSE-I and ASAS survey data as well as from the new LCs reported herein that maximum light during quadrature (Max I and Max II) is often not equal. As a result, Roche modeling of the TYC 2058-753-1 LCs was investigated with and without surface spots to address this asymmetry as well as a diagonally-aligned flat bottom during Min I that was observed in 2017.

Characterization and Validation of the LT-SYS Copper Assay on a Roche Cobas 8000 c502 Analyzer.

PubMed

Kraus, F Bernhard; Mischereit, Marlies; Eller, Christoph; Ludwig-Kraus, Beatrice

2017-02-01

Validation of the LT-SYS quantitative in vitro copper assay on a Roche Cobas 8000 c502 analyzer and comparison with a BIOMED assay on a Roche Cobas Mira analyzer. Imprecision and bias were quantified at different concentration levels (serum and plasma) over a 20-day period. Linearity was assessed covering a range from 4.08 µmol/L to 33.8 µmol/L. Limit of blank (LoB) and limit of detection (LoD) were established based on a total of 120 blank and low-level samples. The method comparison was based on 58 plasma samples. Within-run imprecision ranged from 0.7% to 1.2% and within-laboratory imprecision from 1.4% to 3.3%. Relative bias for the 2 serum pools with known target values was less than 2.5%. The assay did not deviate from linearity over the tested measuring range. LoB and LoD were 0.12 µmol/L and 0.23 µmol/L, respectively. The method comparison revealed an average deviation of 11.5% (2.016 µmol/L), and the linear regression fit was y = 1.464 + 0.795x. The LT-SYS copper assay characterized in this study showed a fully acceptable performance with good degrees of imprecision and bias, no deviation from linearity in the relevant measuring rangem, and very low LoB and LoD. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Definition of Physical Height Systems for Telluric Planets and Moons

NASA Astrophysics Data System (ADS)

Tenzer, Robert; Foroughi, Ismael; Sjöberg, Lars E.; Bagherbandi, Mohammad; Hirt, Christian; Pitoňák, Martin

2018-01-01

In planetary sciences, the geodetic (geometric) heights defined with respect to the reference surface (the sphere or the ellipsoid) or with respect to the center of the planet/moon are typically used for mapping topographic surface, compilation of global topographic models, detailed mapping of potential landing sites, and other space science and engineering purposes. Nevertheless, certain applications, such as studies of gravity-driven mass movements, require the physical heights to be defined with respect to the equipotential surface. Taking the analogy with terrestrial height systems, the realization of height systems for telluric planets and moons could be done by means of defining the orthometric and geoidal heights. In this case, however, the definition of the orthometric heights in principle differs. Whereas the terrestrial geoid is described as an equipotential surface that best approximates the mean sea level, such a definition for planets/moons is irrelevant in the absence of (liquid) global oceans. A more natural choice for planets and moons is to adopt the geoidal equipotential surface that closely approximates the geometric reference surface (the sphere or the ellipsoid). In this study, we address these aspects by proposing a more accurate approach for defining the orthometric heights for telluric planets and moons from available topographic and gravity models, while adopting the average crustal density in the absence of reliable crustal density models. In particular, we discuss a proper treatment of topographic masses in the context of gravimetric geoid determination. In numerical studies, we investigate differences between the geodetic and orthometric heights, represented by the geoidal heights, on Mercury, Venus, Mars, and Moon. Our results reveal that these differences are significant. The geoidal heights on Mercury vary from - 132 to 166 m. On Venus, the geoidal heights are between - 51 and 137 m with maxima on this planet at Atla Regio and Beta Regio. The largest geoid undulations between - 747 and 1685 m were found on Mars, with the extreme positive geoidal heights under Olympus Mons in Tharsis region. Large variations in the geoidal geometry are also confirmed on the Moon, with the geoidal heights ranging from - 298 to 461 m. For comparison, the terrestrial geoid undulations are mostly within ± 100 m. We also demonstrate that a commonly used method for computing the geoidal heights that disregards the differences between the gravity field outside and inside topographic masses yields relatively large errors. According to our estimates, these errors are - 0.3/+ 3.4 m for Mercury, 0.0/+ 13.3 m for Venus, - 1.4/+ 125.6 m for Mars, and - 5.6/+ 45.2 m for the Moon.

The Quantum Dynamics of Chemical Reactions.

DTIC Science & Technology

1983-03-31

of the potential formed by taking a cut perpendicular to the minimum energy path (in Delves coordinates) V (s) = VmeP(s) + Ev(S) (5) ve sn where s is...current density and profiles of the component of jo normal to various straight-line cuts along the streamline field, for the H + H2(0) - H 2 + H...In order to visualize the nature of this topology, we display in Fig. 31 cuts of the equipotentials of V by the XZ. (y. - 0, x) and Y.Z, (’. - n/2, -x

An electrostatic elliptical mirror for neutral polar molecules.

PubMed

González Flórez, A Isabel; Meek, Samuel A; Haak, Henrik; Conrad, Horst; Santambrogio, Gabriele; Meijer, Gerard

2011-11-14

Focusing optics for neutral molecules finds application in shaping and steering molecular beams. Here we present an electrostatic elliptical mirror for polar molecules consisting of an array of microstructured gold electrodes deposited on a glass substrate. Alternating positive and negative voltages applied to the electrodes create a repulsive potential for molecules in low-field-seeking states. The equipotential lines are parallel to the substrate surface, which is bent in an elliptical shape. The mirror is characterized by focusing a beam of metastable CO molecules and the results are compared to the outcome of trajectory simulations.

Conductorlike behavior of a photoemitting dielectric surface

NASA Technical Reports Server (NTRS)

De, B. R.

1979-01-01

It has been suggested in the past that a uniformly illuminated photoemitting dielectric surface of finite extent acquires in the steady state a surface charge distribution as if the surface were conducting (i.e., the surface becomes equipotential). In this paper an analytical proof of this conductorlike behavior is given. The only restrictions are that the photoelectron emission from the surface has azimuthal symmetry and that the photosheath may be assumed to be collisionless. It is tacitly assumed that a steady state is attainable, which means that the photoelectron spectrum has a high-energy cutoff.

Asymmetric ion trap

DOEpatents

Barlow, S.E.; Alexander, M.L.; Follansbee, J.C.

1997-12-02

An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode is disclosed. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity. 4 figs.

The velocity field of growing ear cartilage.

PubMed Central

Cox, R W; Peacock, M A

1978-01-01

The velocity vector field of the growing rabbit ear cartilage has been investigated between 12 and 299 days. Empirical curves have been computed for path lines and for velocities between 12 and 87 days. The tissue movement has been found to behave as an irrotational flow of material. Stream lines and velocity equipotential lines have been calculated and provide akinematic description of the changes during growth. The importance of a knowledge of the velocity vector in physical descriptions of growth and morphological differentiation at the tissue and cellular levels is emphasized. PMID:689993

Proceedings of the Spacecraft Charging Technology Conference: Executive Summary

NASA Technical Reports Server (NTRS)

Pike, C. P.; Whipple, E. C., Jr.; Stevens, N. J.; Minges, M. L.; Lehn, W. L.; Bunn, M. H.

1977-01-01

Aerospace environments are reviewed in reference to spacecraft charging. Modelling, a theoretical scheme which can be used to describe the structure of the sheath around the spacecraft and to calculate the charging currents within, is discussed. Materials characterization is considered for experimental determination of the behavior of typical spacecraft materials when exposed to simulated geomagnetic substorm conditions. Materials development is also examined for controlling and minimizing spacecraft charging or at least for distributing the charge in an equipotential manner, using electrical conductive surfaces for materials exposed to space environment.

Use of altimetry data in a sampling-function approach to the geoid

NASA Technical Reports Server (NTRS)

Lundquist, C. A.; Giacaglia, G. E. O.

1972-01-01

Problems associated with using an altimetry sampling function approach to the geoid are examined. They include: (1) conventent mathematical representation of short-wavelength (eventually approximately 1 deg) features of the geoid or geopotential, (2) utilization of detailed data from only part of the globe (i.e., the oceans) (3) application of appropriate formalism to relate the sea-level equipotential below the atmospheric mass to the external potential above the atmosphere, (4) mathematical applicability of an adopted geopotential representation on the surface of the physical geoid.

Electrodynamic ratchet motor.

PubMed

Lim, Jiufu; Sader, John E; Mulvaney, Paul

2009-03-01

Brownian ratchets produce directed motion through rectification of thermal fluctuations and have been used for separation processes and colloidal transport. We propose a flashing ratchet motor that enables the transduction of electrical energy into rotary micromechanical work. This is achieved through torque generation provided by boundary shaping of equipotential surfaces. The present device contrasts to previous implementations that focus on translational motion. Stochastic simulations elucidate the performance characteristics of this device as a function of its geometry. Miniaturization to nanoscale dimensions yields rotational speeds in excess of 1 kHz, which is comparable to biomolecular motors of similar size.

Comment on "Effects of Magnetic Field Gradient on Ion Beam Current in Cylindrical Hall Ion Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raitses, Y.; Smirnov A.; Fisch, N.J.

It is argued that the key difference of the cylindrical Hall thruster (CHT) as compared to the end-Hall ion source cannot be exclusively attributed to the magnetic field topology [Tang et al. J. Appl. Phys., 102, 123305 (2007)]. With a similar mirror-type topology, the CHT configuration provides the electric field with nearly equipotential magnetic field surfaces and a better suppression of the electron cross-field transport, as compared to both the end-Hall ion source and the cylindrical Hall ion source of Tang et al.

Introduction to the application of QbD principles for the development of monoclonal antibodies.

PubMed

Finkler, Christof; Krummen, Lynne

2016-09-01

Quality by Design (QbD) is a global regulatory initiative with the goal of enhancing pharmaceutical development through the proactive design of pharmaceutical manufacturing process and controls to consistently deliver the intended performance of the product. The principles of pharmaceutical development relevant to QbD are described in the ICH guidance documents (ICHQ8-11). An integrated set of risk assessments and their related elements developed at Roche/Genentech were designed to provide an overview of product and process knowledge for the production of a recombinant monoclonal antibody. This chapter introduces a publication series on the application of Quality by Design for biopharmaceuticals, with a focus on the development of recombinant monoclonal antibodies. The development of and overview on the QbD concept applied by Roche and Genentech is described and essential QbD elements are presented. Copyright © 2016 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

FORMATION OF CENTAURS’ RINGS THROUGH THEIR PARTIAL TIDAL DISRUPTION DURING PLANETARY ENCOUNTERS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hyodo, Ryuki; Charnoz, Sébastien; Genda, Hidenori

Centaurs are minor planets orbiting between Jupiter and Neptune that have or had crossing orbits with one or more giant planets. Recent observations and reinterpretation of previous observations have revealed the existence of ring systems around 10199 Chariklo and 2060 Chiron. However, the origin of the ring systems around such a minor planet is still an open question. Here, we propose that the tidal disruption of a differentiated object that experiences a close encounter with a giant planet could naturally form diverse ring–satellite systems around the Centaurs. During the close encounter, the icy mantle of the passing object is preferentiallymore » ripped off by the planet's tidal force and the debris is distributed mostly within the Roche limit of the largest remnant body. Assuming the existence of a 20−50 wt% silicate core below the icy mantle, a disk of particles is formed when the objects pass within 0.4–0.8 of the planet's Roche limit with the relative velocity at infinity 3−6 km s{sup −1} and 8 hr initial spin period of the body. The resultant ring mass is 0.1%–10% of the central object's mass. Such particle disks are expected to spread radially, and materials spreading beyond the Roche limit would accrete into satellites. Our numerical results suggest that ring formation would be a natural outcome of such extreme close encounters, and Centaurs can naturally have such ring systems because they cross the orbits of the giant planets.« less

Traceability Assessment and Performance Evaluation of Results for Measurement of Abbott Clinical Chemistry Assays on 4 Chemistry Analyzers.

PubMed

Lim, Jinsook; Song, Kyung Eun; Song, Sang Hoon; Choi, Hyun-Jung; Koo, Sun Hoe; Kwon, Gye Choel

2016-05-01

-The traceability of clinical results to internationally recognized and accepted reference materials and reference measurement procedures has become increasingly important. Therefore, the establishment of traceability has become a mandatory requirement for all in vitro diagnostics devices. -To evaluate the traceability of the Abbott Architect c8000 system (Abbott Laboratories, Abbott Park, Illinois), consisting of calibrators and reagents, across 4 different chemistry analyzers, and to evaluate its general performance on the Toshiba 2000FR NEO (Toshiba Medical Systems Corporation, Otawara-shi, Tochigi-ken, Japan). -For assessment of traceability, secondary reference materials were evaluated 5 times, and then bias was calculated. Precision, linearity, and carryover were determined according to the guidelines of the Clinical and Laboratory Standards Institute (Wayne, Pennsylvania). -The biases from 4 different analyzers ranged from -2.33% to 2.70% on the Toshiba 2000FR NEO, -2.33% to 5.12% on the Roche Hitachi 7600 (Roche Diagnostics International, Basel, Switzerland), -0.93% to 2.87% on the Roche Modular, and -2.16% to 2.86% on the Abbott Architect c16000. The total coefficients of variance of all analytes were less than 5%. The coefficients of determination (R(2)) were more than 0.9900. The carryover rate ranged from -0.54% to 0.17%. -Abbott clinical chemistry assays met the performance criteria based on desirable biological variation for precision, bias, and total error. They also showed excellent linearity and carryover. Therefore, these clinical chemistry assays were found to be accurate and reliable and are readily applicable on the various platforms used in this study.

Evaluating new HbA1c methods for adoption by the IFCC and NGSP reference networks using international quality targets.

PubMed

Lenters-Westra, Erna; English, Emma

2017-08-28

As a reference laboratory for HbA1c, it is essential to have accurate and precise HbA1c methods covering a range of measurement principles. We report an evaluation of the Abbott Enzymatic (Architect c4000), Roche Gen.3 HbA1c (Cobas c513) and Tosoh G11 using different quality targets. The effect of hemoglobin variants, other potential interferences and the performance in comparison to both the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and the National Glycohemoglobin Standardization Program (NGSP) reference systems was assessed using certified evaluation protocols. Each of the evaluated HbA1c methods had CVs <3% in SI units and <2% in NGSP units at 46 mmol/mol (6.4%) and 72 mmol/mol (8.7%) and passed the NGSP criteria when compared with six secondary reference measurement procedures (SRMPs). Sigma was 8.6 for Abbott Enzymatic, 3.3 for Roche Cobas c513 and 6.9 for Tosoh G11. No clinically significant interference was detected for the common Hb variants for the three methods. All three methods performed well and are suitable for clinical application in the analysis of HbA1c. Partly based on the result of this study, the Abbott Enzymatic method on the Architect c4000 and the Roche Gen.3 HbA1c on the Cobas c513 are now official, certified IFCC and NGSP SRMPs in the IFCC and NGSP networks. Sigma metrics quality criteria presented in a graph distinguish between good and excellent performance.

Missed detection of significant positive and negative shifts in gentamicin assay: implications for routine laboratory quality practices.

PubMed

Koerbin, Gus; Liu, Jiakai; Eigenstetter, Alex; Tan, Chin Hon; Badrick, Tony; Loh, Tze Ping

2018-02-15

A product recall was issued for the Roche/Hitachi Cobas Gentamicin II assays on 25 th May 2016 in Australia, after a 15 - 20% positive analytical shift was discovered. Laboratories were advised to employ the Thermo Fisher Gentamicin assay as an alternative. Following the reintroduction of the revised assay on 12 th September 2016, a second reagent recall was made on 20 th March 2017 after the discovery of a 20% negative analytical shift due to erroneous instrument adjustment factor. The practices of an index laboratory were examined to determine how the analytical shifts evaded detection by routine internal quality control (IQC) and external quality assurance (EQA) systems. The ability of the patient result-based approaches, including moving average (MovAvg) and moving sum of outliers (MovSO) approaches in detecting these shifts were examined. Internal quality control data of the index laboratory were acceptable prior to the product recall. The practice of adjusting IQC target following a change in assay method resulted in the missed negative shift when the revised Roche assay was reintroduced. While the EQA data of the Roche subgroup showed clear negative bias relative to other laboratory methods, the results were considered as possible 'matrix effect'. The MovAvg method detected the positive shift before the product recall. The MovSO did not detect the negative shift in the index laboratory but did so in another laboratory 5 days before the second product recall. There are gaps in current laboratory quality practices that leave room for analytical errors to evade detection.

Falsely Elevated Plasma Creatinine Due to an Immunoglobulin M Paraprotein.

PubMed

McGill, Mitchell R; Vijayan, Anitha; Trulock, Elbert P; Witt, Chad A; Kohler, Giselle D; Scott, Mitchell G

2016-11-01

The most common method for measuring plasma creatinine is based on its reaction with picric acid. However, enzymatic methods are becoming more popular due to improved specificity. We present a case of falsely elevated plasma creatinine values obtained by an enzymatic method that turned out to be due to a monoclonal immunoglobulin M (IgM) paraprotein. A 63-year-old woman evaluated for lung transplantation had falsely increased plasma creatinine levels (1.54-1.71mg/dL; corresponding to estimated glomerular filtration rates of 32-36 mL/min/1.73m 2 ) as measured by the Roche Creatinine plus enzymatic assay when compared with the picric acid-based procedure and several other enzymatic methods, which gave plasma creatinine values of 0.7 to 0.8mg/dL. Serum protein electrophoresis revealed an IgM κ light chain paraprotein. Removal of high-molecular-weight (>30kDa) proteins by ultrafiltration reduced the patient's plasma creatinine level by the Roche enzymatic method to 0.7mg/dL. Addition of the patient's immunoglobulin fraction to plasma from other patients with normal plasma creatinine levels resulted in values that were increased by 0.58 to 0.62mg/dL. Furthermore, removal of non-IgM immunoglobulins with protein G-coupled beads did not eliminate the interference from the patient's plasma. Taken together, these studies demonstrate that falsely elevated plasma creatinine values by the Roche enzymatic method can be due to an IgM paraprotein. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Body fluid matrix evaluation on a Roche cobas 8000 system.

PubMed

Owen, William E; Thatcher, Mindy L; Crabtree, Karolyn J; Greer, Ryan W; Strathmann, Frederick G; Straseski, Joely A; Genzen, Jonathan R

2015-09-01

Chemical analysis of body fluids is commonly requested by physicians. Because most commercial FDA-cleared clinical laboratory assays are not validated by diagnostic manufacturers for "non-serum" and "non-plasma" specimens, laboratories may need to complete additional validation studies to comply with regulatory requirements regarding body fluid testing. The objective of this report is to perform recovery studies to evaluate potential body fluid matrix interferences for commonly requested chemistry analytes. Using an IRB-approved protocol, previously collected clinical body fluid specimens (biliary/hepatic, cerebrospinal, dialysate, drain, pancreatic, pericardial, peritoneal, pleural, synovial, and vitreous) were de-identified and frozen (-20°C) until experiments were performed. Recovery studies (spiking with high concentration serum, control, and/or calibrator) were conducted using 10% spiking solution by volume; n=5 specimens per analyte/body fluid investigated. Specimens were tested on a Roche cobas 8000 system (c502, c702, e602, and ISE modules). In all 80 analyte/body fluid combinations investigated (including amylase, total bilirubin, urea nitrogen, carbohydrate antigen 19-9, carcinoembryonic antigen, cholesterol, chloride, creatinine, glucose, potassium, lactate dehydrogenase, lipase, rheumatoid factor, sodium, total protein, triglycerides, and uric acid), the average percent recovery was within predefined acceptable limits (less than ±10% from the calculated ideal recovery). The present study provides evidence against the presence of any systematic matrix interference in the analyte/body fluid combinations investigated on the Roche cobas 8000 system. Such findings support the utility of ongoing body fluid validation initiatives conducted to maintain compliance with regulatory requirements. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Direct comparisons of Illumina vs. Roche 454 sequencing technologies on the same microbial community DNA sample.

PubMed

Luo, Chengwei; Tsementzi, Despina; Kyrpides, Nikos; Read, Timothy; Konstantinidis, Konstantinos T

2012-01-01

Next-generation sequencing (NGS) is commonly used in metagenomic studies of complex microbial communities but whether or not different NGS platforms recover the same diversity from a sample and their assembled sequences are of comparable quality remain unclear. We compared the two most frequently used platforms, the Roche 454 FLX Titanium and the Illumina Genome Analyzer (GA) II, on the same DNA sample obtained from a complex freshwater planktonic community. Despite the substantial differences in read length and sequencing protocols, the platforms provided a comparable view of the community sampled. For instance, derived assemblies overlapped in ~90% of their total sequences and in situ abundances of genes and genotypes (estimated based on sequence coverage) correlated highly between the two platforms (R(2)>0.9). Evaluation of base-call error, frameshift frequency, and contig length suggested that Illumina offered equivalent, if not better, assemblies than Roche 454. The results from metagenomic samples were further validated against DNA samples of eighteen isolate genomes, which showed a range of genome sizes and G+C% content. We also provide quantitative estimates of the errors in gene and contig sequences assembled from datasets characterized by different levels of complexity and G+C% content. For instance, we noted that homopolymer-associated, single-base errors affected ~1% of the protein sequences recovered in Illumina contigs of 10× coverage and 50% G+C; this frequency increased to ~3% when non-homopolymer errors were also considered. Collectively, our results should serve as a useful practical guide for choosing proper sampling strategies and data possessing protocols for future metagenomic studies.

The effect of cardiac electric anisotropy on epicardial potential fields during ventricular repolarization.

PubMed

Spaggiari, S; Baruffi, S; Macchi, E; Traversa, M; Arisi, G; Taccardi, B

1986-11-01

We tried to establish whether some of the manifestations of electrical anisotropy previously observed on the canine ventricular epicardium during the spread of excitation were also present during repolarization, with the appropriate polarity. To this end we determined the potential distribution on the ventricular surface of exposed dog hearts during ventricular excitation and repolarization. The ventricles were paced by means of epicardial or intramural electrodes. During the early stages of ventricular excitation following epicardial pacing we observed typical, previously described potential patterns, with negative, elliptical equipotential lines surrounding the pacing site, and two maxima aligned along the direction of subepicardial fibers. Intramural pacing gave rise to similar patterns. The axis joining the maxima, however, was oriented along the direction of intramural fibers. The repolarization potential pattern relating to epicardial excitation exhibited some features similar to those observed during the spread of excitation, namely the presence of families of elliptical equipotential lines around the pacing site, with pairs of potential extrema along the major or minor axes of the ellipses or both. The location of the extrema and the distribution of the epicardial potential gradients during repolarization suggested the presence of anisotropic current generators mainly oriented along the direction of deep myocardial fibers, with some contribution from more superficial sources which were oriented along the direction of subepicardial fibers. Deep stimulation elicited more complicated epicardial patterns whose interpretation is still obscure. We conclude that the electrical anisotropy of the heart affects the distribution of repolarization potentials and probably the strength of electrical generators during ventricular repolarization.

Electroencephalogram (EEG) and Magnetoencephalogram (MEG) as Tools for Evaluation of Cognitive Function

NASA Technical Reports Server (NTRS)

Fender, Derek H.; Hestenes, John D.

1985-01-01

We have developed computerized analysis and display techniques to help identify the origins of visually evoked scalped potentials (VESP). The potentials are recorded simultaneously from many electrodes (usually 40 to 48) spaced over the region of the scalp where appreciable evoked potentials are found in response to particular stimulus. Contour mapping algorithms are then used to display the time behavior of equipotential surfaces on the scalp during the VESP. We then use an optimization technique to select the parameters of arrays of current dipole sources within the model until the model equipotential field distribution closely fits the measured data. Computer graphics are then used to display, as a movie, the actual and model scalp potential fields and the parameters of the dipole generators within the model head during the course of VESP activity. We have devised reaction time tests that involve potentially separable stages of cognitive processing and utilize stimuli that produce measurable cognition-related features in the late component of the evoked potential. We have used these techniques to determine the loci in the brain where known cognition-related features in the evoked potential are generated and we have explored the extent to which each of these features can be related to the reaction time tasks. We have also examined the temporal-spatial aspects of their cerebral involvement. Our current work is planned to characterize the age-related changes in the processes performed by such sources. We also use a neuromagnetometer to measure the evoked magnetic fields in similar circumstances; we will discuss the relative merits of the two methodologies.

Normal Gravity Fields and Equipotential Ellipsoids of Small Objects in the Solar System: A Closed-form Solution in Ellipsoidal Harmonics up to the Second Degree

NASA Astrophysics Data System (ADS)

Hu, Xuanyu

2017-11-01

We propose a definition for the normal gravity fields and normal figures of small objects in the solar system, such as asteroids, cometary nuclei, and planetary moons. Their gravity fields are represented as series of ellipsoidal harmonics, ensuring more robust field evaluation in the proximity of an arbitrary, convex shape than using spherical harmonics. The normal gravity field, approximate to the actual field, can be described by a finite series of three terms, that is, degree zero, and the zonal and sectoral harmonics of degree two. The normal gravity is that of an equipotential ellipsoid, defined as the normal ellipsoid of the body. The normal ellipsoid may be distinct from the actual figure. We present a rationale for specifying and a numerical method for determining the parameters of the normal ellipsoid. The definition presented here generalizes the convention of the normal spheroid of a large, hydrostatically equilibrated planet, such as Earth. Modeling the normal gravity and the normal ellipsoid is relevant to studying the formation of the “rubble pile” objects, which may have been accreted, or reorganized after disruption, under self-gravitation. While the proposed methodology applies to convex, approximately ellipsoidal objects, those bi-lobed objects can be treated as contact binaries comprising individual convex subunits. We study an exemplary case of the nearly ellipsoidal Martian moon, Phobos, subject to strong tidal influence in its present orbit around Mars. The results allude to the formation of Phobos via gravitational accretion at some further distance from Mars.

Laboratory evaluation of the Liat HIV Quant (IQuum) whole-blood and plasma HIV-1 viral load assays for point-of-care testing in South Africa.

PubMed

Scott, Lesley; Gous, Natasha; Carmona, Sergio; Stevens, Wendy

2015-05-01

Point-of-care (POC) HIV viral load (VL) testing offers the potential to reduce turnaround times for antiretroviral therapy monitoring, offer near-patient acute HIV diagnosis in adults, extend existing centralized VL services, screen women in labor, and prompt pediatrics to early treatment. The Liat HIV Quant plasma and whole-blood assays, prerelease version, were evaluated in South Africa. The precision, accuracy, linearity, and agreement of the Liat HIV Quant whole-blood and plasma assays were compared to those of reference technologies (Roche CAP CTMv2.0 and Abbott RealTime HIV-1) on an HIV verification plasma panel (n = 42) and HIV clinical specimens (n = 163). HIV Quant plasma assay showed good performance, with a 2.7% similarity coefficient of variation (CV) compared to the Abbott assay and a 1.8% similarity CV compared to the Roche test on the verification panel, and 100% specificity. HIV Quant plasma had substantial agreement (pc [concordance correlation] = 0.96) with Roche on clinical specimens and increased variability (pc = 0.73) in the range of <3.0 log copies/ml range with the HIV Quant whole-blood assay. HIV Quant plasma assay had good linearity (2.0 to 5.0 log copies/ml; R(2) = 0.99). Clinical sensitivity at a viral load of 1,000 copies/ml of the HIV Quant plasma and whole-blood assays compared to that of the Roche assay (n = 94) was 100% (confidence interval [CI], 95.3% to 100%). The specificity of HIV Quant plasma was 88.2% (CI, 63.6% to 98.5%), and that for whole blood was 41.2% (CI, 18.4% to 67.1%). No virological failure (downward misclassification) was missed. Liat HIV Quant plasma assay can be interchanged with existing VL technology in South Africa. Liat HIV Quant whole-blood assay would be advantageous for POC early infant diagnosis at birth and adult adherence monitoring and needs to be evaluated further in this clinical context. LIAT cartridges currently require cold storage, but the technology is user-friendly and robust. Clinical cost and implementation modeling is required. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

The skin microbiome in psoriatic arthritis: methodology development and pilot data.

PubMed

Castelino, Madhura; Eyre, Stephen; Moat, John; Fox, Graeme; Martin, Paul; Ijaz, Umer; Quince, Christopher; Ho, Pauline; Upton, Mathew; Barton, Anne

2015-02-26

Skin microbiota are likely to be important in the development of conditions such as psoriatic arthritis. Profiling the bacterial community in the psosriatic plaques will contribute to our understanding of the role of the skin microbiome in these conditions. The aim of this work was to determine the optimum study design for work on the skin microbiome with use of the MiSeq platform. The objectives were to compare data generated from two platforms for two primer pairs in a low density mock bacterial community. DNA was obtained from two low density mock communities of 11 diverse bacterial strains (with and without human DNA supplementation) and from swabs taken from the skin of four healthy volunteers. The DNA was amplified with primer pairs covering hypervariable regions of the 16S rRNA gene: primers 63F and 519R (V1-V3), and 347F and 803R (V3-V4). The resultant libraries were indexed for the MiSeq and Roche454 platforms and sequenced. Both datasets were de-noised, cleaned of chimeras, and analysed by use of QIIME software (version 1.8.0). No significant difference in the diversity indices at the phylum and the genus level between the platforms was seen. Comparison of the diversity indices for the mock community data for the two primer pairs demonstrated that the V3-V4 hypervariable region had significantly better capture of bacterial diversity than did the V1-V3 region. Amplification with the same primer pairs showed strong concordance within each platform (98·9-99·8%), with negligible effect of spiked human DNA contamination. Comparison at the family level classification between samples processed on the MiSeq and Roche454 platforms using the V3-V4 hypervariable region also showed a high level of concordance (87%), although less so for the V1-V3 primers (10%). The pilot data from healthy volunteers were similar. Results obtained from the V3-V4 16S rRNA hypervariable region, sequencing on the MiSeq and Roche454 platforms, were concordant between replicates, and between each other. These findings suggest that the MiSeq platform, and these primers, is a comparable method for determining skin microbiota to the widely used Roche454 methodology. NIHR Manchester Musculoskeletal Biomedical Research Unit. Copyright © 2015 Elsevier Ltd. All rights reserved.

77 FR 61423 - Notice of Adjustment of Statewide Per Capita Impact Indicator

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-09

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency Notice of Adjustment of Statewide Per Capita Impact Indicator AGENCY: Federal Emergency Management Agency, DHS. ACTION: Notice... FURTHER INFORMATION CONTACT: William Roche, Recovery Directorate, Federal Emergency Management Agency, 500...

Ocean current surface measurement using dynamic elevations obtained by the GEOS-3 radar altimeter

NASA Technical Reports Server (NTRS)

Leitao, C. D.; Huang, N. E.; Parra, C. G.

1977-01-01

Remote Sensing of the ocean surface from the GEOS-3 satellite using radar altimeter data has confirmed that the altimeter can detect the dynamic ocean topographic elevations relative to an equipotential surface, thus resulting in a reliable direct measurement of the ocean surface. Maps of the ocean dynamic topography calculated over a one month period and with 20 cm contour interval are prepared for the last half of 1975. The Gulf Stream is observed by the rapid slope change shown by the crowding of contours. Cold eddies associated with the current are seen as roughly circular depressions.

Electrostatic force microscopy on oriented graphite surfaces: coexistence of insulating and conducting behaviors.

PubMed

Lu, Yonghua; Muñoz, M; Steplecaru, C S; Hao, Cheng; Bai, Ming; Garcia, N; Schindler, K; Esquinazi, P

2006-08-18

We present measurements of the electric potential fluctuations on the surface of highly oriented pyrolytic graphite using electrostatic force and atomic force microscopy. Micrometric domainlike potential distributions are observed even when the sample is grounded. Such potential distributions are unexpected given the good metallic conductivity of graphite because the surface should be an equipotential. Our results indicate the coexistence of regions with "metalliclike" and "insulatinglike" behaviors showing large potential fluctuations of the order of 0.25 V. In lower quality graphite, this effect is not observed. Experiments are performed in Ar and air atmospheres.

78 FR 64232 - Notice of Adjustment of Statewide Per Capita Impact Indicator

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-28

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency Notice of Adjustment of Statewide Per Capita Impact Indicator AGENCY: Federal Emergency Management Agency, DHS. ACTION: Notice... INFORMATION CONTACT: William Roche, Recovery Directorate, Federal Emergency Management Agency, 500 C Street SW...

Vitamin B(12) Immunoassay on Roche Elecsys 2010: Effects of High Excess Concentration of Serum Vitamin B(12) in CKD Patients on Parenteral Administration.

PubMed

Basu, Surupa; Chaudhuri, Subimal

2011-10-01

Vitamin B(12) being water soluble is excreted in the urine when administered in excess. The probability of finding an abnormally excess serum concentration would be almost surreal. We report a peculiar clinical situation that may impact the vitamin B(12) immunoassay on the Roche Elecsys 2010 due to excess analyte concentration. In separate episodes (Feb and June 2010), the Biochemistry laboratory of a tertiary-care hospital, Kolkata, India, encountered two critically ill patients with background chronic kidney disease (CKD), low urine output, and on cyanocoabalamin supplementation, who had serum vitamin B(12) concentrations far exceeding expected values; even post dialysis. The B(12) assays (pmol/l) were performed using electrochemiluminiscence immunoassay on Roche Elecsys 2010, the assay validity confirmed by concomitant quality control runs. The immunoassays failed to deliver results, flagged with "signal level below limit". Biotin therapy was ruled out as a possible interferent. In the first episode, re-assay of a repeat draw yielded same outcome; outsourcing on Immulite provided concentration of >738 pmol/l. Serial dilution gave result of >29520 pmol/l on Elecsys 2010. In the second, we gained from past experience. Vitamin B(12) concentration >59040 pmol/l was conveyed to the treating nephrologist the very day. The B(12) immunoassay on the Elecsys 2010 employs sequential incubation steps for competitive binding that is compromised in the event of abnormally excess B(12) concentration in patient sera akin to the prozone effect. This knowledge may be beneficial while assaying sera of CKD patients to avoid financial loss due unnecessary repeats and delay in turnaround time.

[Comparison between the LightCycler CMV Quant Kit (Roche Diagnostics) with a standardized in-house Taqman assay for cytomegalovirus blood viral load quantification].

PubMed

Alain, S; Lachaise, V; Hantz, S; Denis, F

2010-04-01

The broad use of cytomegalovirus (CMV) viral load quantification in blood to follow immunosuppressed patients need standardized assays. Choice of whole blood allows follow-up for several viruses and simplifies pretreatment and storage of samples. We therefore evaluated the LightCycler CMV Quant Kit (Roche Diagnostics) assay on whole blood after a manual extraction (High Pure viral nucleic acid kit, Roche Diagnostics), using as a reference an in-house Taqman assay (LC1UL83) which has been validated in various clinical situations. A panel obtained by serial dilutions of a virion stock in CMV whole blood, a commercial plasma quality control (VQC, Argène, France) crude or diluted in whole blood, infected cells extracts and 46 clinical samples from transplanted patients were tested simultaneously by both techniques. For plasma quality controls, both PCR assays are correlated VQC (R(2)=0.93). On whole blood or infected cells dilutions, correlation shows an overestimation by the LC1UL83 assay (mean 1.2 log copies/ml) over 3 log though R(2)=0.94. Results with CMV Quant Kit are closer to expected values. Results on clinical samples are close to quality controls with a lower variation of quantification (0.76 log copies/ml). CMV Quant Kit performs well when compared with a clinically validated PCR. Quality control results showed discrepancies between plasma and whole blood, demonstrating the need for whole blood standardized panels to compare the methods. This underlines the need to follow a patient with the same technique during his follow-up. Copyright 2009 Elsevier Masson SAS. All rights reserved.

Performance evaluation of the Roche Tina-quant Cystatin C assay and reference interval for cystatin C in healthy blood donors.

PubMed

Erlandsen, Erland J; Randers, Else

2010-07-01

To evaluate the performance of the Roche Diagnostics Tina-quant Cystatin C particle enhanced immuno turbidimetric assay for the measurement of plasma and serum cystatin C, and to establish reference intervals for cystatin C in healthy blood donors. The cystatin C measurements were performed on the Roche Modular Analytics P automated clinical chemistry analyzer. The cystatin C assay was linear in the measuring range 0.40-7.00 mg/L. Within-run CVs < or = 2.0%, between-run CVs < or = 4.2%, and total CVs < or = 5.5% in plasma pools and in commercial cystatin C control materials (range 1.0-4.7 mg/L). Recovery was 99.4-109.3%. No interference was detected from haemoglobin < 0.9 mmol/L, bilirubin < 330 micromol/L and Intralipid < 20 g/L. Measurement of cystatin C in Li-heparin plasma did not differ significantly from cystatin C measured in serum. Forty patient samples run on the Modular Analytics P (y) were compared to the Siemens Cystatin C assay on the BN II (x): y = 0.817x + 0.270, Sy.x = 0.168 (Deming regression). The non-parametric reference interval for cystatin C was calculated to be 0.41-0.91 mg/L in females (n = 86), and 0.43-0.94 mg/L in males (n = 76). The Mann-Whitney U test showed a significant difference between the two genders (p = 0.015), but the difference was without clinical relevance. A common reference interval for both genders (n = 162) was calculated to be 0.41-0.92 mg/L. The performance of the Tina-quant Cystatin C assay was acceptable for clinical use.

Performance of an Early Infant Diagnostic Test, AmpliSens DNA-HIV-FRT, Using Dried Blood Spots Collected from Children Born to Human Immunodeficiency Virus-Infected Mothers in Ukraine

PubMed Central

Shanmugam, Vedapuri; Azarskova, Marianna; Nguyen, Shon; Hurlston, Mackenzie; Sabatier, Jennifer; Zhang, Guoqing; Osmanov, Saladin; Ellenberger, Dennis; Yang, Chunfu; Vitek, Charles; Liulchuk, Maria; Nizova, Natalya

2015-01-01

An accurate accessible test for early infant diagnosis (EID) is crucial for identifying HIV-infected infants and linking them to treatment. To improve EID services in Ukraine, dried blood spot (DBS) samples obtained from 237 HIV-exposed children (≤18 months of age) in six regions in Ukraine in 2012 to 2013 were tested with the AmpliSens DNA-HIV-FRT assay, the Roche COBAS AmpliPrep/COBAS TaqMan (CAP/CTM) HIV-1 Qual test, and the Abbott RealTime HIV-1 Qualitative assay. In comparison with the paired whole-blood results generated from AmpliSens testing at the oblast HIV reference laboratories in Ukraine, the sensitivity was 0.99 (95% confidence interval [CI], 0.95 to 1.00) for the AmpliSens and Roche CAP/CTM Qual assays and 0.96 (95% CI, 0.90 to 0.98) for the Abbott Qualitative assay. The specificity was 1.00 (95% CI, 0.97 to 1.00) for the AmpliSens and Abbott Qualitative assays and 0.99 (95% CI, 0.96 to 1.00) for the Roche CAP/CTM Qual assay. McNemar analysis indicated that the proportions of positive results for the tests were not significantly different (P > 0.05). Cohen's kappa (0.97 to 0.99) indicated almost perfect agreement among the three tests. These results indicated that the AmpliSens DBS and whole-blood tests performed equally well and were comparable to the two commercially available EID tests. More importantly, the performance characteristics of the AmpliSens DBS test meets the World Health Organization EID test requirements; implementing AmpliSens DBS testing might improve EID services in resource-limited settings. PMID:26447114

Analytical and clinical performance of thyroglobulin autoantibody assays in thyroid cancer follow-up.

PubMed

Katrangi, Waddah; Grebe, Stephan K G; Algeciras-Schimnich, Alicia

2017-10-26

While thyroglobulin autoantibodies (TgAb) can result in false low serum thyroglobulin (Tg) immunoassay (IA) measurements, they might also be indicators of disease persistence/recurrence. Hence, accurate TgAb measurement, in addition to Tg quantification, is crucial for thyroid cancer monitoring. We compared the analytical and clinical performance of four commonly used TgAb IAs. We measured Tg by mass spectrometry (Tg-MS) and by four pairs of Tg and TgAb IAs (Beckman, Roche, Siemens, Thermo) in 576 samples. Limit of quantitation (LOQ) and manufacturers' upper reference interval cut-off (URI) were used for comparisons. Clinical performance was assessed by receiving operator characteristics (ROC) curve analysis. Quantitative and qualitative agreement between TgAb-IAs was moderate with R2 of 0.20-0.70 and κ from 0.41-0.66 using LOQ and 0.47-0.71 using URI. In samples with TgAb interference, detection rates of TgAb were similar using LOQ and URI for Beckman, Siemens, and Thermo, but much lower for the Roche TgAb-IA when the URI was used. In TgAb positive cases, the ROC areas under the curve (AUC) for the TgAb-IAs were 0.59 (Beckman), 0.62 (Siemens), 0.59 (Roche), and 0.59 (Thermo), similar to ROC AUCs achieved with Tg. Combining Tg and TgAb measurements improved the ROC AUCs compared to Tg or TgAb alone. TgAb-IAs show significant qualitative and quantitative differences. For 2 of the 4 TgAb-IAs, using the LOQ improves the detection of interfering TgAbs. All assays showed suboptimal clinical performance when used as surrogate markers of disease, with modest improvements when Tg and TgAb were combined.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Naoz, Smadar; Stephan, Alexander P.; Fragos, Tassos

The formation of black hole (BH) low-mass X-ray binaries (LMXB) poses a theoretical challenge, as low-mass companions are not expected to survive the common-envelope scenario with the BH progenitor. Here we propose a formation mechanism that skips the common-envelope scenario and relies on triple-body dynamics. We study the evolution of hierarchical triples following the secular dynamical evolution up to the octupole-level of approximation, including general relativity, tidal effects, and post-main-sequence evolution such as mass loss, changes to stellar radii, and supernovae. During the dynamical evolution of the triple system the “eccentric Kozai-Lidov” mechanism can cause large eccentricity excitations in themore » LMXB progenitor, resulting in three main BH-LMXB formation channels. Here we define BH-LMXB candidates as systems where the inner BH-companion star crosses its Roche limit. In the “eccentric” channel (∼81% of the LMXBs in our simulations) the donor star crosses its Roche limit during an extreme eccentricity excitation while still on a wide orbit. Second, we find a “giant” LMXB channel (∼11%), where a system undergoes only moderate eccentricity excitations but the donor star fills its Roche-lobe after evolving toward the giant branch. Third, we identify a “classical” channel (∼8%), where tidal forces and magnetic braking shrink and circularize the orbit to short periods, triggering mass-transfer. Finally, for the giant channel we predict an eccentric (∼0.3–0.6) preferably inclined (∼40°, ∼140°) tertiary, typically on a wide enough orbit (∼10{sup 4} au) to potentially become unbound later in the triple evolution. While this initial study considers only one representative system and neglects BH natal kicks, we expect our scenario to apply across a broad region of parameter space for triple-star systems.« less

THE QUASI-ROCHE LOBE OVERFLOW STATE IN THE EVOLUTION OF CLOSE BINARY SYSTEMS CONTAINING A RADIO PULSAR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benvenuto, O. G.; De Vito, M. A.; Horvath, J. E., E-mail: adevito@fcaglp.unlp.edu.ar, E-mail: foton@iag.usp.br

We study the evolution of close binary systems formed by a normal (solar composition), intermediate-mass-donor star together with a neutron star. We consider models including irradiation feedback and evaporation. These nonstandard ingredients deeply modify the mass-transfer stages of these binaries. While models that neglect irradiation feedback undergo continuous, long-standing mass-transfer episodes, models including these effects suffer a number of cycles of mass transfer and detachment. During mass transfer, the systems should reveal themselves as low-mass X-ray binaries (LMXBs), whereas when they are detached they behave as binary radio pulsars. We show that at these stages irradiated models are in amore » Roche lobe overflow (RLOF) state or in a quasi-RLOF state. Quasi-RLOF stars have radii slightly smaller than their Roche lobes. Remarkably, these conditions are attained for an orbital period as well as donor mass values in the range corresponding to a family of binary radio pulsars known as ''redbacks''. Thus, redback companions should be quasi-RLOF stars. We show that the characteristics of the redback system PSR J1723-2837 are accounted for by these models. In each mass-transfer cycle these systems should switch from LMXB to binary radio pulsar states with a timescale of approximately one million years. However, there is recent and fast growing evidence of systems switching on far shorter, human timescales. This should be related to instabilities in the accretion disk surrounding the neutron star and/or radio ejection, still to be included in the model having the quasi-RLOF state as a general condition.« less

The gene space in wheat: the complete γ-gliadin gene family from the wheat cultivar Chinese Spring.

PubMed

Anderson, Olin D; Huo, Naxin; Gu, Yong Q

2013-06-01

The complete set of unique γ-gliadin genes is described for the wheat cultivar Chinese Spring using a combination of expressed sequence tag (EST) and Roche 454 DNA sequences. Assemblies of Chinese Spring ESTs yielded 11 different γ-gliadin gene sequences. Two of the sequences encode identical polypeptides and are assumed to be the result of a recent gene duplication. One gene has a 3' coding mutation that changes the reading frame in the final eight codons. A second assembly of Chinese Spring γ-gliadin sequences was generated using Roche 454 total genomic DNA sequences. The 454 assembly confirmed the same 11 active genes as the EST assembly plus two pseudogenes not represented by ESTs. These 13 γ-gliadin sequences represent the complete unique set of γ-gliadin genes for cv Chinese Spring, although not ruled out are additional genes that are exact duplications of these 13 genes. A comparison with the ESTs of two other hexaploid cultivars (Butte 86 and Recital) finds that the most active genes are present in all three cultivars, with exceptions likely due to too few ESTs for detection in Butte 86 and Recital. A comparison of the numbers of ESTs per gene indicates differential levels of expression within the γ-gliadin gene family. Genome assignments were made for 6 of the 13 Chinese Spring γ-gliadin genes, i.e., one assignment from a match to two γ-gliadin genes found within a tetraploid wheat A genome BAC and four genes that match four distinct γ-gliadin sequences assembled from Roche 454 sequences from Aegilops tauschii, the hexaploid wheat D-genome ancestor.

Assessment of MagNA pure LC extraction system for detection of human papillomavirus (HPV) DNA in PreservCyt samples by the Roche AMPLICOR and LINEAR ARRAY HPV tests.

PubMed

Stevens, Matthew P; Rudland, Elice; Garland, Suzanne M; Tabrizi, Sepehr N

2006-07-01

Roche Molecular Systems recently released two PCR-based assays, AMPLICOR and LINEAR ARRAY (LA), for the detection and genotyping, respectively, of human papillomaviruses (HPVs). The manual specimen processing method recommended for use with both assays, AmpliLute, can be time-consuming and labor-intensive and is open to potential specimen cross-contamination. We evaluated the Roche MagNA Pure LC (MP) as an alternative for specimen processing prior to use with either assay. DNA was extracted from cervical brushings, collected in PreservCyt media, by AmpliLute and MP using DNA-I and Total Nucleic Acid (TNA) kits, from 150 patients with histologically confirmed cervical abnormalities. DNA was amplified and detected by AMPLICOR and the LA HPV test. Concordances of 96.5% (139 of 144) (kappa=0.93) and 95.1% (135 of 142) (kappa=0.90) were generated by AMPLICOR when we compared DNA extracts from AmpliLute to MP DNA-I and TNA, respectively. The HPV genotype profiles were identical in 78.7 and 74.7% of samples between AmpliLute and DNA-I or TNA, respectively. To improve LA concordance, all 150 specimens were extracted by MP DNA-I protocol after the centrifugation of 1-ml PreservCyt samples. This modified approach improved HPV genotype concordance levels between AmpliLute and MP DNA-I to 88.0% (P=0.043) without affecting AMPLICOR sensitivity. Laboratories that have an automated MP extraction system would find this procedure more feasible and easier to handle than the recommended manual extraction method and could substitute such extractions for AMPLICOR and LA HPV tests once internally validated.

Performance Evaluation of the Bioneer AccuPower® HIV-1 Quantitative RT-PCR kit: Comparison with the Roche COBAS® AmpliPrep/COBAS TaqMan® HIV-1 Test Ver.2.0 for Quantification of HIV-1 Viral Load in Indonesia.

PubMed

Kosasih, Agus Susanto; Sugiarto, Christine; Hayuanta, Hubertus Hosti; Juhaendi, Runingsih; Setiawan, Lyana

2017-08-08

Measurement of viral load in human immunodeficiency virus type 1 (HIV-1) infected patients is essential for the establishment of a therapeutic strategy. Several assays based on qPCR are available for the measurement of viral load; they differ in sample volume, technology applied, target gene, sensitivity and dynamic range. The Bioneer AccuPower® HIV-1 Quantitative RT-PCR is a novel commercial kit that has not been evaluated for its performance. This study aimed to evaluate the performance of the Bioneer AccuPower® HIV-1 Quantitative RT-PCR kit. In total, 288 EDTA plasma samples from the Dharmais Cancer Hospital were analyzed with the Bioneer AccuPower® HIV-1 Quantitative RT-PCR kit and the Roche COBAS? AmpliPrep/COBAS® TaqMan® HIV-1 version 2.0 (CAP/CTM v2.0). The performance of the Bioneer assay was then evaluated against the Roche CAP/CTM v2.0. Overall, there was good agreement between the two assays. The Bioneer assay showed significant linear correlation with CAP/CTM v2.0 (R2=0.963, p<0.001) for all samples (N=118) which were quantified by both assays, with high agreement (94.9%, 112/118) according to the Bland-Altman model. The mean difference between the quantitative values measured by Bioneer assay and CAP/CTM v2.0 was 0.11 Log10 IU/mL (SD=0.26). Based on these results, the Bioneer assay can be used to quantify HIV-1 RNA in clinical laboratories.

Characterization of the scope and magnitude of biotin interference in susceptible Roche Elecsys competitive and sandwich immunoassays.

PubMed

Trambas, Christina; Lu, Zhong; Yen, Tina; Sikaris, Ken

2018-03-01

Background Biotin interference is a significant problem to which at-risk laboratories must now be attuned. We sought to systematically characterize the nature of this interference in Roche immunoassays. Methods Known concentrations of biotin were titrated into serum samples and the effects on competitive and sandwich immunoassays were analysed. The maximum and minimum concentrations examined reflect those likely to be achieved in individuals on 5 to 10 mg supplements at the lower end, and 100 to 300 mg biotin at the high end. Results A high variability in biotin tolerance was observed. Some assays, such as troponin T, TSH and antithyroid antibodies, were extremely sensitive to the lower concentrations of biotin (15.6 and 31.3 ng/mL), whereas the majority of assays were relatively resistant. At concentrations ≥500 ng/mL, all assays showed significant interference from biotin but, again, the magnitude of the interference was variable. The more sensitive assays showed profound analytical bias at biotin concentrations that occur with high-dose therapy. Conclusion Our data demonstrate high variability in biotin tolerance across Roche immunoassays. The shape of the dose-response curves provides more detailed information than the single manufacturer-quoted figure for biotin tolerance. Accordingly, these data may be used by laboratories for more accurate risk assessment in predicting the effects of biotin. Our data may also be extrapolated to guide timing of blood tests in patients on high-dose biotin therapy: it demonstrates the number of half-lives required to withhold biotin in order to decrease its concentration to below a given assay tolerance.

Exoplanet recycling in massive white-dwarf debris discs

NASA Astrophysics Data System (ADS)

van Lieshout, R.; Kral, Q.; Charnoz, S.; Wyatt, M. C.; Shannon, A.

2018-05-01

Several tens of white dwarfs are known to host circumstellar discs of dusty debris, thought to arise from the tidal disruption of rocky bodies originating in the star's remnant planetary system. This paper investigates the evolution of such discs if they are very massive, as may be the case if their progenitor was a terrestrial planet, moon, or dwarf planet. Assuming the discs are physically thin and flat, like Saturn's rings, their evolution is governed by Poynting-Robertson drag or viscous spreading, where the disc's effective viscosity is due to self-gravity wakes. For discs with masses ≳ 1026 g, located in the outer parts of the tidal disruption zone, viscous spreading dominates the evolution, and mass is transported both in- and outwards. When outwards-spreading material flows beyond the Roche limit, it coagulates into new (minor) planets in a process analogous to the ongoing formation of moonlets at the outer edge of Saturn's rings. The newly formed bodies migrate outwards by exchanging angular momentum with the disc and coalesce into larger objects through mutual collisions. Eventually, the disc's Roche-limit overflow recycles tens of percent of the original disc mass; most ends up in a single large body near 2:1 mean-motion resonance with the disc's outer edge. Hence, the recycling of a tidally disrupted super-Earth, for example, could yield an Earth-mass planet on a ˜10-h orbit, located in the habitable zone for 2-to-10-Gyr-old white dwarfs. The recycling process also creates a population of smaller bodies just outside the Roche limit, which may explain the minor planets recently postulated to orbit WD 1145+017.

Crystallization-induced dynamic resolution R-epimer from 25-OCH3-PPD epimeric mixture.

PubMed

Zhang, Sainan; Tang, Yun; Cao, Jiaqing; Zhao, Chen; Zhao, Yuqing

2015-11-15

25-OCH3-PPD is a promising antitumor dammarane sapogenin isolated from the total saponin-hydrolyzed extract of Panax ginseng berry and Panax notoginseng leaves. 20(R)-25-OCH3-PPD was more potent as an anti-cancer agent than 20(S)-25-OCH3-PPD and epimeric mixture of 25-OCH3-PPD. This paper describes the rapid separation process of the R-epimer of 25-OCH3-PPD from its epimeric mixture by crystallization-induced dynamic resolution (CIDR). The optimized CIDR process was based on single factor analysis and nine well-planned orthogonal design experiments (OA9 matrix). A rapid and sensitive reverse phase high-performance liquid chromatographic (HPLC) method with evaporative light-scattering detector (ELSD) was developed and validated for the quantitation of 25-OCH3-PPD epimeric mixture and crystalline product. Separation and quantitation were achieved with a silica column using a mobile phase consisting of methanol and water (87:13, v/v) at a flow rate of 1.0mL/min. The ELSD detection was performed at 50°C and 3L/min. Under conditions involving 3mL of 95% ethanol, 8% HCl, and a hermetically sealed environment for 72h, the maximum production of 25(R)-OCH3-PPD was achieved with a chemical purity of 97% and a total yield of 87% through the CIDR process. The 25(R)-OCH3-PPD was nearly completely separated from the 220mg 25-OCH3-PPD epimeric mixture. Overall, a simple and steady small-batch purification process for the large-scale production of 25(R)-OCH3-PPD from 25-OCH3-PPD epimeric mixture was developed. Copyright © 2015 Elsevier B.V. All rights reserved.

[Comparison of manual and automated (MagNA Pure) nucleic acid isolation methods in molecular diagnosis of HIV infections].

PubMed

Alp, Alpaslan; Us, Dürdal; Hasçelik, Gülşen

2004-01-01

Rapid quantitative molecular methods are very important for the diagnosis of human immunodeficiency virus (HIV) infections, assessment of prognosis and follow up. The purpose of this study was to compare and evaluate the performances of conventional manual extraction method and automated MagNA Pure system, for the nucleic acid isolation step which is the first and most important step in molecular diagnosis of HIV infections. Plasma samples of 35 patients in which anti-HIV antibodies were found as positive by microparticule enzyme immunoassay and confirmed by immunoblotting method, were included in the study. The nucleic acids obtained simultaneously by manual isolation kit (Cobas Amplicor, HIV-1 Monitor Test, version 1.5, Roche Diagnostics) and automated system (MagNA Pure LC Total Nucleic Acid Isolation Kit, Roche Diagnostics), were amplified and detected in Cobas Amplicor (Roche Diagnostics) instrument. Twenty three of 35 samples (65.7%) were found to be positive, and 9 (25.7%) were negative by both of the methods. The agreement between the methods were detected as 91.4%, for qualitative results. Viral RNA copies detected by manual and MagNA Pure isolation methods were found between 76.0-7.590.000 (mean: 487.143) and 113.0-20.300.0000 (mean: 2.174.097) copies/ml, respectively. When both of the overall and individual results were evaluated, the number of RNA copies obtained with automatized system, were found higher than the manual method (p<0.05). Three samples which had low numbers of nucleic acids (113, 773, 857, respectively) with MagNA Pure, yielded negative results with manual method. In conclusion, the automatized MagNA Pure system was found to be a reliable, rapid and practical method for the isolation of HIV-RNA.

Discordances with HIV-1 RNA quantitative determinations by three commercial assays in Pointe Noire, Republic of Congo.

PubMed

Bruzzone, Bianca; Bisio, Francesca; Caligiuri, Patrizia; Mboungou, Franc A Mayinda; Nigro, Nicola; Sticchi, Laura; Ventura, Agostina; Saladini, Francesco; Zazzi, Maurizio; Icardi, Giancarlo; Viscoli, Claudio

2014-07-01

Accurate HIV-1 RNA quantitation is required to support the scale up of antiretroviral therapy in African countries. Extreme HIV-1 genetic variability in Africa may affect the ability of commercially available assays to detect and quantify HIV-1 RNA accurately. The aim of this study was to compare three real-time PCR assays for quantitation of plasma HIV-1 RNA levels in patients from the Republic of Congo, an area with highly diversified HIV-1 subtypes and recombinants. The Abbott RealTime HIV-1, BioMérieux HIV-1 EasyQ test 1.2 and Cobas AmpliPrep/Cobas TaqMan HIV-1 1.0 were compared for quantitation of HIV-1 RNA in 37 HIV-1 seropositive pregnant women enrolled in the Kento-Mwana project for prevention of mother-to-child transmission in Pointe-Noire, Republic of Congo. The sample panel included a variety of HIV-1 subtypes with as many as 21 (56.8%) putative unique recombinant forms. Qualitative detection of HIV-1 RNA was concordant by all three assays in 33/37 (89.2%) samples. Of the remaining 4 (10.8%) samples, all were positive by Roche, three by Abbott and none by BioMérieux. Differences exceeding 1Log in positive samples were found in 4/31 (12.9%), 10/31 (32.3%) and 5/31 (16.1%) cases between Abbott and BioMérieux, Roche and BioMérieux, and Abbott and Roche, respectively. In this sample panel representative of highly polymorphic HIV-1 in Congo, the agreement among the three assays was moderate in terms of HIV-1 RNA detectability and rather inconsistent in terms of quantitation. Copyright © 2014. Published by Elsevier B.V.

Environment-Mediated Drug Resistance in Neuroblastoma

DTIC Science & Technology

2013-10-01

mice. A. MRI of abdominal cavity of representative mice from NB-Tag and NB- TagxIL6KOat 3 different ages. B. There were no difference between growth...radioimmunoprecipitation assay (RIPA) buffer supplemented with 1 tablet of complete mini-EDTA protease inhibitor cocktail (Roche Diagnostics) or halt

A Relational Frame Theory Account of Empathy

ERIC Educational Resources Information Center

Vilardaga, Roger

2009-01-01

The current paper proposes a Relational Frame Theory (RFT, Hayes, Barnes-Holmes, & Roche, 2001a) conceptualization of empathy and perspective taking that follows previous literature outlining a relationship between those phenomena and general functioning. Deictic framing, a relational operant investigated by RFT researchers, constitutes the…

Impact of pH on Urine Chemistry Assayed on Roche Analyzers.

PubMed

Cohen, R; Alkouri, R; Tostivint, I; Djiavoudine, S; Mestari, F; Dever, S; Atlan, G; Devilliers, C; Imbert-Bismut, F; Bonnefont-Rousselot, D; Monneret, D

2017-10-01

The pH may impact the concentration of certain urinary parameters, making urine pre-treatment questionable. 1) Determining the impact of pH in vitro on the urinary concentration of chemistry parameters assayed on Roche Modular analyzers. 2) Evaluating whether concentrations depended on pH in non-pretreated urines from patients. 1) The optimal urinary pH values for each measurement were: 6.3 ± 0.8 (amylase), < 5.5 (calcium and magnesium), < 6.5 (phosphorus), > 6.5 (uric acid). Urinary creatinine, sodium and urea concentrations were not pH-dependent. 2) In urines from patients, the pH was negatively associated with the concentration of some urinary parameters. However, concentrations of all the parameters were strongly and positively correlated with urinary creatinine, and relationships with pH were no longer evidenced after creatinine-normalization. The need for urine pH adjustment does not seem necessary when considering renal function. However, from an analytical and accreditation standpoint, the relationship between urine pH and several parameters justifies its measurement.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hellier, Coel; Anderson, D. R.; Smalley, B.

WASP-19b has the shortest orbital period of any known exoplanet, orbiting at only 1.2 times the Roche tidal radius. By observing the Rossiter-McLaughlin effect we show that WASP-19b's orbit is aligned, with {lambda} = 4.{sup 0}6 {+-} 5.{sup 0}2. Using, in addition, a spectroscopic vsin I and the observed rotation period we conclude that the obliquity, {psi}, is less than 20{sup 0}. Further, the eccentricity of the orbit is less than 0.02. We argue that hot Jupiters with orbital periods as short as that of WASP-19b are two orders of magnitude less common than hot Jupiters at the 3-4 daymore » 'pileup'. We discuss the evolution of WASP-19b's orbit and argue that most likely it was first moved to near twice the Roche limit by third-body interactions, and has since spiralled inward to its current location under tidal decay. This is compatible with a stellar tidal-dissipation quality factor, Q'{sub *}, of order 10{sup 7}.« less

A Neutron Star-White Dwarf Binary Model for Repeating Fast Radio Burst 121102

NASA Astrophysics Data System (ADS)

Gu, Wei-Min; Dong, Yi-Ze; Liu, Tong; Ma, Renyi; Wang, Junfeng

2016-06-01

We propose a compact binary model for the fast radio burst (FRB) repeaters, where the system consists of a magnetic white dwarf (WD) and a neutron star (NS) with strong bipolar magnetic fields. When the WD fills its Roche lobe, mass transfer will occur from the WD to the NS through the inner Lagrange point. The accreted magnetized materials may trigger magnetic reconnection when they approach the NS surface, and therefore the electrons can be accelerated to an ultra-relativistic speed. In this scenario, the curvature radiation of the electrons moving along the NS magnetic field lines can account for the characteristic frequency and the timescale of an FRB. Owing to the conservation of angular momentum, the WD may be kicked away after a burst, and the next burst may appear when the system becomes semi-detached again through the gravitational radiation. By comparing our analyses with the observations, we show that such an intermittent Roche-lobe overflow mechanism can be responsible for the observed repeating behavior of FRB 121102.

Influence of stellar radiation pressure on flow structure in the envelope of hot-Jupiter HD 209458b

NASA Astrophysics Data System (ADS)

Cherenkov, A. A.; Bisikalo, D. V.; Kosovichev, A. G.

2018-03-01

Close-in exoplanets are subjected to extreme radiation of their host stars. Photometric observations of the hot-Jupiter HD 209458b transit by HST/STIS detected strong absorption in the Ly α line, thus indicating the existence of a hydrogen envelope extending beyond the Roche lobe. The gasdynamic modelling (Bisikalo et al.) showed that the stable structure of this envelope is maintained by the balance between the Roche lobe overfilling and stellar wind pressure. Obviously, the dynamics and stability of the envelope can be affected by stellar radiation pressure. Using 3D gasdynamic simulations, we study the impact of radiation pressure in the Ly α line on the envelope of hot-Jupiter HD 209458b, and show that the effect is not strong enough to significantly affect the gasdynamics in the system. For a detectable radiation pressure effect the intensity of the Ly α line has to be by two orders of magnitude greater.

SEPAC data analysis in support of the environmental interaction program

NASA Technical Reports Server (NTRS)

Lin, Chin S.

1990-01-01

Injections of nonrelativistic electron beams from an isolated equipotential conductor into a uniform background of plasma and neutral gas were simulated using a two dimensional electrostatic particle code. The ionization effects of spacecraft charging are examined by including interactions of electrons with neutral gas. The simulations show that the conductor charging potential decreases with increasing neutral background density due to the production of secondary electrons near the conductor surface. In the spacecraft wake, the background electrons accelerated towards the charged space craft produced an enhancement of secondary electrons and ions. Simulations run for longer times indicate that the spacecraft potential is further reduced and short wavelength beam-plasma oscillations appear. The results are applied to explain the space craft charging potential measured during the SEPAC experiments from Spacelab 1. A second paper is presented in which a two dimensional electrostatic particle code was used to study the beam radial expansion of a nonrelativistic electron beam injected from an isolated equipotential conductor into a background plasma. The simulations indicate that the beam radius is generally proportional to the beam electron gyroradius when the conductor is charged to a large potential. The simulations also suggest that the charge buildup at the beam stagnation point causes the beam radial expansion. From a survey of the simulation results, it is found that the ratio of the beam radius to the beam electron gyroradius increases with the square root of beam density and decreases inversely with beam injection velocity. This dependence is explained in terms of the ratio of the beam electron Debye length to the ambient electron Debye length. These results are most applicable to the SEPAC electron beam injection experiments from Spacelab 1, where high charging potential was observed.

Improvement of patient return electrodes in electrosurgery by experimental investigations and numerical field calculations.

PubMed

Golombeck, M A; Dössel, O; Raiser, J

2003-09-01

Numerical field calculations and experimental investigations were performed to examine the heating of the surface of human skin during the application of a new electrode design for the patient return electrode. The new electrode is characterised by an equipotential ring around the central electrode pads. A multi-layer thigh model was used, to which the patient return electrode and the active electrode were connected. The simulation geometry and the dielectric tissue parameters were set according to the frequency of the current. The temperature rise at the skin surface due to the flow of current was evaluated using a two-step numerical solving procedure. The results were compared with experimental thermographical measurements that yielded a mean value of maximum temperature increase of 3.4 degrees C and a maximum of 4.5 degrees C in one test case. The calculated heating patterns agreed closely with the experimental results. However, the calculated mean value in ten different numerical models of the maximum temperature increase of 12.5 K (using a thermodynamic solver) exceeded the experimental value owing to neglect of heat transport by blood flow and also because of the injection of a higher test current, as in the clinical tests. The implementation of a simple worst-case formula that could significantly simplify the numerical process led to a substantial overestimation of the mean value of the maximum skin temperature of 22.4 K and showed only restricted applicability. The application of numerical methods confirmed the experimental assertions and led to a general understanding of the observed heating effects and hotspots. Furthermore, it was possible to demonstrate the beneficial effects of the new electrode design with an equipotential ring. These include a balanced heating pattern and the absence of hotspots.

CRE Activation in Antiestrogen Resistance

DTIC Science & Technology

2005-05-01

differences in transfection efficiency, 0.1 ug of a plasmid containing the Renilla luciferase gene was also cotransfected into the cells. Both plasmid DNAs...containing the Renilla luciferase gene was also cotransfected into the cells. Both plasmid DNAs were added to a mix of Fugene 6 (Roche) and serum free

Genome Wide Characterization of Simple Sequence Repeats in Cucumber

USDA-ARS?s Scientific Manuscript database

The whole genome sequence of the cucumber cultivar Gy14 was recently sequenced at 15× coverage with the Roche 454 Titanium technology. The microsatellite DNA sequences (simple sequence repeats, SSRs) in the assembled scaffolds were computationally explored and characterized. A total of 112,073 SSRs ...

Identification and initial characterization of a novel turkey-origin picobirnavirus using a metagenomic approach

USDA-ARS?s Scientific Manuscript database

Using the Genome Sequencer FLX Titanium technology (Roche, 454 Life Sciences), a ribonucleic acid (RNA) virus-specific metagenome was prepared using the pooled intestinal contents collected from North Carolina turkey flocks experiencing enteric disease signs. This analysis produced 6526 contigs rang...

Analysis of genetic diversity using SNP markers in oat

USDA-ARS?s Scientific Manuscript database

A large-scale single nucleotide polymorphism (SNP) discovery was carried out in cultivated oat using Roche 454 sequencing methods. DNA sequences were generated from cDNAs originating from a panel of 20 diverse oat cultivars, and from Diversity Array Technology (DArT) genomic complexity reductions fr...

The contribution of air-fluidization to the mobility of rapid flowslides involving fine particles

NASA Astrophysics Data System (ADS)

Stilmant, Frédéric; Dewals, Benjamin; Archambeau, Pierre; Erpicum, Sébastien; Pirotton, Michel

2016-04-01

Air-fluidization can be the origin of the long runout of gravitational flows involving fine particles such as ash. An excessive air pore pressure dramatically reduces the friction angle of the material as long as this pressure has not been dissipated, which occurs during the flow. This phenomenon can be modelled thanks to the 2D depth-averaged equations of mass and momentum conservation and an additional transport equation for basal pore pressure evolution (Iverson and Denlinger, 2001). In this contribution, we discuss the application of this model in relation to recent experimental results on air-fluidized flows by Roche et al. (2008) and Roche (2012). The experimental results were used to set a priori the value of the diffusion coefficient in the model, taking into account the difference of scale between the experiments and real-world applications. We also compare the model predictions against detailed observations of a well-documented historical event, the collapse of a fly-ash heap in Belgium (Stilmant et al., 2015). In particular, we analyse the influence of the different components of the model on the results (pore pressure dissipation vs. pore pressure generation). The diffusion coefficient which characterizes the dissipation of air pore pressure is found sufficiently low for maintaining a fluidized flow over hundreds of meters. The study concludes that an air-fluidization theory is consistent with the field observations. These findings are particularly interesting as they seem not in line with the mainstream acceptation in landslide modelling that air generally plays a secondary role (e.g., Legros, 2002). References Iverson, R.M., Denlinger, R.P., 2001. Flow of variably fluidized granular masses across three-dimensional terrain - 1. Coulomb mixture theory. J. Geophys. Res. 106, 537 552. Legros, F., 2002. The mobility of long-runout landslides. Eng. Geol. 63, 301-331. Roche, O., 2012. Depositional processes and gas pore pressure in pyroclastic flows: an experimental perspective. Bull. Volcanol. 74, 1807-1820. Roche, O., Montserrat, S., Niño, Y., Tamburrino, A., 2008. Experimental observations of water-like behavior of initially fluidized, dam break granular flows and their relevance for the propagation of ash-rich pyroclastic flows. J. Geophys. Res. 113, B12203. Stilmant, F., Pirotton, M., Archambeau, P., Erpicum, S., & Dewals, B. (2015). Can the collapse of a fly ash heap develop into an air-fluidized flow? - Reanalysis of the Jupille accident (1961). Geomorphology, 228, 746-755.

454-pyrosequencing: A tool for discovery and biomarker development

USDA-ARS?s Scientific Manuscript database

The Roche GS-FLX (454) sequencer has made possible what was thought impossible just a few years ago: sequence >1 million high-quality nucleotide reads (mean 400 bp) in less than 12 h. This technology provides valuable species-specific sequence information, and is a valuable tool to discover and und...

Peer Group Learning in Roche Pharma Development

ERIC Educational Resources Information Center

Boulden, George P.; De Laat, Richard

2005-01-01

Pharma Development has used action learning to help participants in their 360[degrees] feedback programme develop their leadership competencies. The article describes how the programme was designed, supported and run across four sites over a period of 2 years. The programme was systematically evaluated and found to be successful in meeting its…

Sharing Cookies: A Case Study

ERIC Educational Resources Information Center

Salls, Jenny

2014-01-01

Rational number interpretations can include part-whole, measure, ratio, quotient, and operator. These are all subconstructs of partitioning (Barnett-Clarke et al. 2010; Behr et al. 1980; Clarke, Roche, and Mitchell 2008; Flores, Samson, and Yanik 2006). Each of these subconstructs uses different cognitive skills (Driscoll 1984), so it is important…

Ultra high-throughput nucleic acid sequencing as a tool for virus discovery in the turkey gut.

USDA-ARS?s Scientific Manuscript database

Recently, the use of the next generation of nucleic acid sequencing technology (i.e., 454 pyrosequencing, as developed by Roche/454 Life Sciences) has allowed an in-depth look at the uncultivated microorganisms present in complex environmental samples, including samples with agricultural importance....

Spiral Learning: An Introductory Course on Reading LOTE Online

ERIC Educational Resources Information Center

Schuetze, Ulf

2010-01-01

In teaching reading, authentic texts with abundant lexical items and complex grammatical structures are typically used (Roche, 1992). Unfortunately, this has been a challenge for students enrolled in reading courses developed for English as a Second Language (ESL) as well as Languages Other Than English (LOTE) students. Students often translate…

27 CFR 12.31 - List of approved names by country.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., Chateau Yquem, Chateauneuf-du-Pape, Chenas, Chevalier-Montrachet, Chiroubles, Clos de la Roche, Clos de Vougeot, Corton, Corton-Charlemagne, Cote de Beaune, Cote de Beaune-Villages, Cote de Brouilly, Cote de Nuits, Cote de Nuits-Villages, Cote Rotie, Coteaux du Layon, Cotes du Rhone, Echezeaux, Entre-Deux-Mers...

27 CFR 12.31 - List of approved names by country.

Code of Federal Regulations, 2011 CFR

2011-04-01

..., Chateau Yquem, Chateauneuf-du-Pape, Chenas, Chevalier-Montrachet, Chiroubles, Clos de la Roche, Clos de Vougeot, Corton, Corton-Charlemagne, Cote de Beaune, Cote de Beaune-Villages, Cote de Brouilly, Cote de Nuits, Cote de Nuits-Villages, Cote Rotie, Coteaux du Layon, Cotes du Rhone, Echezeaux, Entre-Deux-Mers...

Systematic Review and Network Meta-analysis of Idiopathic Pulmonary Fibrosis Treatments.

PubMed

Fleetwood, Kelly; McCool, Rachael; Glanville, Julie; Edwards, Susan C; Gsteiger, Sandro; Daigl, Monica; Fisher, Mark

2017-03-01

The antifibrotics pirfenidone and nintedanib are both approved for the treatment of idiopathic pulmonary fibrosis (IPF) by regulatory agencies and are recommended by health technology assessment bodies. Other treatments such as N-acetylcysteine are used in clinical practice but have not received regulatory approval. No head-to-head trials have been conducted to directly compare the efficacy of these therapies in IPF. To compare the efficacy of treatments for IPF. A systematic review was conducted up to April 2015. Phase II/III randomized controlled trials in adults with IPF were eligible. A Bayesian network meta-analysis (NMA) was used to compare pirfenidone, nintedanib, and N-acetylcysteine with respect to forced vital capacity (FVC) and mortality. Nine studies were included in the NMA. For change from baseline in FVC, the NMA indicated that pirfenidone and nintedanib were more effective than placebo after 1 year (pirfenidone vs. placebo: difference = 0.12 liter (L), 95% credible interval [CrI] = 0.03-0.21 L; nintedanib vs. placebo: difference = 0.11 L, 95% CrI = 0.00-0.22 L). There was no evidence that N-acetylcysteine had an effect on FVC compared with placebo (N-acetylcysteine vs. placebo: difference = 0.01 L, 95% CrI = -0.15-0.17 L). Patients treated with pirfenidone also had a lower risk of experiencing a decline in percent predicted FVC of ≥ 10% over 1 year (odds ratio [OR]: 0.58, 95% CrI = 0.40-0.88), whereas there was no conclusive evidence of a difference between nintedanib and placebo (OR: 0.65, 95% CrI = 0.42-1.02). The NMA indicated that pirfenidone reduced all-cause mortality relative to placebo over 1 year (hazard ratio [HR]: 0.52, 95% CrI = 0.28-0.92). There was no evidence of a difference in all-cause mortality between nintedanib and placebo (HR: 0.70, 95% CrI = 0.32-1.55), or N-acetylcysteine and placebo (HR: 2.00, 95% CrI=0.46-8.62). Our primary analysis of the available evidence indicates that over 1 year, pirfenidone and nintedanib are effective at reducing lung-function decline, and pirfenidone may reduce the odds of experiencing a decline in percent predicted FVC of ≥10% compared with placebo in the first year of treatment. The results of our analysis also suggest that pirfenidone improves survival. Fleetwood is an employee of Quantics Consulting. McCool and Glanville are employees of York Health Economics Consortium (YHEC). Quantics and YHEC received funding from F. Hoffmann-La Roche for conducting the systematic review and network meta-analysis reported in this paper. Edwards, Gsteiger, and Daigl are employees of F. Hoffmann-La Roche. Fisher was employed by InterMune UK, a wholly owned Roche subsidiary, until July 2015. He is currently employed by FIECON, which has received funding from F. Hoffmann-La Roche for consulting services. The systematic review and network meta-analysis reported in this paper were conducted by Fleetwood (Quantics Consulting) and McCool and Glanville (YHEC), funded by F. Hoffmann-La Roche. The original network analysis was funded by InterMune. Study concept and design were contributed by Edwards, Gsteiger, and Daigl, along with Fleetwood, McCool, and Glanville. Fleetwood, McCool, and Glanville collected the data, with assistance from Edwards, Gsteiger, and Daigl. Data interpretation was performed by Fleetwood and Fisher, with assistance from the other authors. The manuscript was written by Fleetwood, McCool, and Glanville, with assistance from Edwards, Daigl, and Fisher, and revised by all the authors.

Etalon (standard) for surface potential distribution produced by electric activity of the heart.

PubMed

Szathmáry, V; Ruttkay-Nedecký, I

1981-01-01

The authors submit etalon (standard) equipotential maps as an aid in the evaluation of maps of surface potential distributions in living subjects. They were obtained by measuring potentials on the surface of an electrolytic tank shaped like the thorax. The individual etalon maps were determined in such a way that the parameters of the physical dipole forming the source of the electric field in the tank corresponded to the mean vectorcardiographic parameters measured in a healthy population sample. The technique also allows a quantitative estimate of the degree of non-dipolarity of the heart as the source of the electric field.

Comment on 'Effects of magnetic field gradient on ion beam current in cylindrical Hall ion source' [J. Appl. Phys. 102, 123305 (2007)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raitses, Y.; Smirnov, A.; Fisch, N. J.

It is argued that the key difference in the cylindrical Hall thruster (CHT) as compared to the end-Hall ion source cannot be exclusively attributed to the magnetic field topology [Tang et al., J. Appl. Phys. 102, 123305 (2007)]. With a similar mirror-type topology, the CHT configuration provides the electric field with nearly equipotential magnetic field surfaces and a better suppression of the electron cross-field transport, as compared to both the end-Hall ion source and the cylindrical Hall ion source of [Tang et al., J. Appl. Phys. 102, 123305 (2007)].

78 FR 25259 - Notice of Intent To Grant an Exclusive License; Integrata Security, LLC

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-30

..., 9800 Savage Road, Suite 6848, Fort George G. Meade, MD 20755-6848. FOR FURTHER INFORMATION CONTACT: Marian T. Roche, Director, Technology Transfer Program, 9800 Savage Road, Suite 6848, Fort George G. Meade, MD 20755-6848, telephone (443) 634-3514. Dated: April 24, 2013. Aaron Siegel, Alternate OSD...

Swedish Defence Research Abstracts 82/83-2 (Froe Foersvars Forsknings Referat 82/83-2).

DTIC Science & Technology

1983-08-01

alarm (78) Carbon dioxide retention inside motorcycle helmets (79) Vibration and decompression gas bubbles (80) No effects of nootropic drugs on memory... nootropic drugs on memory and psychomotor performance during reduced air pressure (in English) S. Levander and others Report I from the Roche Clinical Unit

75 FR 52932 - Notice of Intent To Grant an Exclusive License; Doar, Pekuin, Sall Limited Liability Company

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-30

... Government- Owned invention as described in U.S. Patent No. 6,404,407 entitled ``Ridge laser with oxidized... National Security Agency Technology Transfer Program, 9800 Savage Road, Suite 6541, Fort George G. Meade, MD 20755-6541. FOR FURTHER INFORMATION CONTACT: Marian T. Roche, Director, Technology Transfer...

The American cranberry mitochondrial genome reveals the presence of selenocysteine (tRNA-Sec and SECIS) insertion machinery in land plants

USDA-ARS?s Scientific Manuscript database

The American cranberry (Vaccinium macrocarpon Ait.) mitochondrial genome was assembled and reconstructed from whole genome 454 Roche GS-FLX and Illumina shotgun sequences. Compared with other Asterids, the reconstruction of the genome revealed an average size mitochondrion (459,678 nt) with comparat...

Sequencing Technologies Panel at SFAF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turner, Steve; Fiske, Haley; Knight, Jim

2010-06-02

From left to right: Steve Turner of Pacific Biosciences, Haley Fiske of Illumina, Jim Knight of Roche, Michael Rhodes of Life Technologies and Peter Vander Horn of Life Technologies' Single Molecule Sequencing group discuss new sequencing technologies and applications on June 2, 2010 at the "Sequencing, Finishing, Analysis in the Future" meeting in Santa Fe, NM

New Generation Sequencing Technology Panel at SFAF-Part II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fiske, Haley; Turner, Steve; Rhodes, Michael

2009-05-27

From left to right: Haley Fiske of Illumina Inc., Steve Turner of Pacific Biosciences, Michael Rhodes of Applied Biosystems, Patrice Milos of Helicos Biosciences and Tim Harkins of Roche Diagnostics answer questions in a forum moderated by Bob Fulton at the "Sequencing, Finishing, Analysis in the Future" meeting in Santa Fe, NM.

New Generation Sequencing Technology Panel at SFAF-Part I

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fiske, Haley; Turner, Steve; Rhodes, Michael

2009-05-27

From left to right: Haley Fiske of Illumina Inc., Steve Turner of Pacific Biosciences, Michael Rhodes of Applied Biosystems, Patrice Milos of Helicos Biosciences and Tim Harkins of Roche Diagnostics answer questions in a forum moderated by Bob Fulton at the "Sequencing, Finishing, Analysis in the Future" meeting in Santa Fe, NM.

Listening Walks and Singing Maps

ERIC Educational Resources Information Center

Cardany, Audrey Berger

2011-01-01

The Listening Walk by Paul Showers and illustrated by Aliki, and "It's My City: A Singing Map" by April Pulley Sayre with pictures by Denis Roche, provide two examples of texts that aid in building children's phonological awareness for reading and music. The author describes each narrative and discusses its function as a springboard to composition…

An Experimental Analysis of the Relation between Assigned Grades and Instructor Evaluations

ERIC Educational Resources Information Center

Smith, Dale L.; Cook, Patrick; Buskist, William

2011-01-01

The perceived relation between assigned student grades and instructor evaluations of teaching has been the subject of much debate, though few laboratory studies have been conducted with adequate controls. Marsh and Roche suggested that experimental field studies may be a particularly promising avenue for further analyses of this relation. The…

40 CFR Table 2 to Subpart F of... - Organic Hazardous Air Pollutants

Code of Federal Regulations, 2010 CFR

2010-07-01

... (N,N-) 121697 Diethyl sulfate 64675 Dimethylbenzidine (3,3″-) 119937 Dimethylformamide (N,N-) 68122... Hexachlorobenzene 118741 Hexachlorobutadiene 87683 Hexachloroethane 67721 Hexane 110543 Hydroquinone 123319... ethylene glycol, diethylene glycol, and triethylene glycol R-(OCH2 CH2n-OR where: n=1, 2, or 3; R=alkyl or...

40 CFR Table 2 to Subpart F of... - Organic Hazardous Air Pollutants

Code of Federal Regulations, 2012 CFR

2012-07-01

... (N,N-) 121697 Diethyl sulfate 64675 Dimethylbenzidine (3,3′-) 119937 Dimethylformamide (N,N-) 68122... Hexachlorobenzene 118741 Hexachlorobutadiene 87683 Hexachloroethane 67721 Hexane 110543 Hydroquinone 123319... ethylene glycol, diethylene glycol, and triethylene glycol R-(OCH2 CH2n-OR where: n=1, 2, or 3; R=alkyl or...

The Neurobiological Basis and Potential Modification of Emotional Intelligence through Affective / Behavioral Training

DTIC Science & Technology

2013-04-01

alertness (Banks and Dinges, 2007; Punjabi et al., 2003; Van Dongen and Maislin, 2003). Relative to being well rested, prolonged sleep debt may also...Sleep Research Society Sleep credit, grey matter and emotion 7 Punjabi , N. M., Bandeen-Roche, K. and Young, T. Predictors of objective sleep tendency in

The Moon's orbit history and inferences on its origin

NASA Technical Reports Server (NTRS)

Conway, B. A.

1984-01-01

A frequency dependent model of tidal friction was used to determine the evolution of the Earth-Moon system. The analysis considers the lunar orbit eccentricity and inclination, the solar tide on the Earth, Earth oblateness, and higher order terms in the tidal potential. A solution of the equations governing the precession of the Earth's rotational angular momentum and the lunar ascending node is found. The history is consistent with a capture origin for the Moon. It rules out the origin of the Moon by fission. Results are shown for a range of assumed values for the lunar tidal dissipation. Tidal dissipation within the Moon, during what would be the immediate postcapture period, is shown to be capable of significantly heating the Moon. The immediate postcapture orbit has a periapsis within the Earth's Roche limit. Capture into resonance with the Earth's gravitational field as this orbit tidally evolves is suggested to be a mechanism to prevent so close, an approach. It is shown that the probability of such capture is negligibly small and alternative hypotheses for the survival of the Roche limit passage is offered.

Advancing the understanding of progression in multiple sclerosis: an interview with Shibeshih Belachew.

PubMed

Belachew, Shibeshih

2018-02-01

Shibeshih Belachew speaks to Laura Dormer, Commissioning Editor: Dr Shibeshih Belachew, MD, PhD, is a Senior Medical Director for Multiple Sclerosis (MS) Disease Area in Global Product Development Medical Affairs at Roche (Basel, Switzerland). Prior to joining Roche in January 2016, he was Director of MS Franchise and Head of Medical Director's office for Biogen Region Europe and Canada. Previously at Biogen he also served as a Director in Global Neurology for the natalizumab program in Cambridge (MA, USA). Prior to joining industry, he was a Clinical Professor of Neurology at the University of Liège in Belgium. Shibeshih completed neurology postgraduate training at the University of Liège and has a PhD in Biomedical Science in the field of Developmental Neurobiology. Shibeshih has been a post-doctoral fellow in the Laboratory of Cellular and Synaptic Neurophysiology at the National Institutes of Health (Bethesda, MD, USA) and later at the Center for Neuroscience Research of Children's National Medical Center in Washington DC. He is a member of the Belgian Neurological Society.

Constraining Roche-Lobe Overflow Models Using the Hot-Subdwarf Wide Binary Population

NASA Astrophysics Data System (ADS)

Vos, Joris; Vučković, Maja

2017-12-01

One of the important issues regarding the final evolution of stars is the impact of binarity. A rich zoo of peculiar, evolved objects are born from the interaction between the loosely bound envelope of a giant, and the gravitational pull of a companion. However, binary interactions are not understood from first principles, and the theoretical models are subject to many assumptions. It is currently agreed upon that hot subdwarf stars can only be formed through binary interaction, either through common envelope ejection or stable Roche-lobe overflow (RLOF) near the tip of the red giant branch (RGB). These systems are therefore an ideal testing ground for binary interaction models. With our long term study of wide hot subdwarf (sdB) binaries we aim to improve our current understanding of stable RLOF on the RGB by comparing the results of binary population synthesis studies with the observed population. In this article we describe the current model and possible improvements, and which observables can be used to test different parts of the interaction model.

Computer vision-based sorting of Atlantic salmon (Salmo salar) fillets according to their color level.

PubMed

Misimi, E; Mathiassen, J R; Erikson, U

2007-01-01

Computer vision method was used to evaluate the color of Atlantic salmon (Salmo salar) fillets. Computer vision-based sorting of fillets according to their color was studied on 2 separate groups of salmon fillets. The images of fillets were captured using a digital camera of high resolution. Images of salmon fillets were then segmented in the regions of interest and analyzed in red, green, and blue (RGB) and CIE Lightness, redness, and yellowness (Lab) color spaces, and classified according to the Roche color card industrial standard. Comparisons of fillet color between visual evaluations were made by a panel of human inspectors, according to the Roche SalmoFan lineal standard, and the color scores generated from computer vision algorithm showed that there were no significant differences between the methods. Overall, computer vision can be used as a powerful tool to sort fillets by color in a fast and nondestructive manner. The low cost of implementing computer vision solutions creates the potential to replace manual labor in fish processing plants with automation.

Comparative evaluation of three automated systems for DNA extraction in conjunction with three commercially available real-time PCR assays for quantitation of plasma Cytomegalovirus DNAemia in allogeneic stem cell transplant recipients.

PubMed

Bravo, Dayana; Clari, María Ángeles; Costa, Elisa; Muñoz-Cobo, Beatriz; Solano, Carlos; José Remigia, María; Navarro, David

2011-08-01

Limited data are available on the performance of different automated extraction platforms and commercially available quantitative real-time PCR (QRT-PCR) methods for the quantitation of cytomegalovirus (CMV) DNA in plasma. We compared the performance characteristics of the Abbott mSample preparation system DNA kit on the m24 SP instrument (Abbott), the High Pure viral nucleic acid kit on the COBAS AmpliPrep system (Roche), and the EZ1 Virus 2.0 kit on the BioRobot EZ1 extraction platform (Qiagen) coupled with the Abbott CMV PCR kit, the LightCycler CMV Quant kit (Roche), and the Q-CMV complete kit (Nanogen), for both plasma specimens from allogeneic stem cell transplant (Allo-SCT) recipients (n = 42) and the OptiQuant CMV DNA panel (AcroMetrix). The EZ1 system displayed the highest extraction efficiency over a wide range of CMV plasma DNA loads, followed by the m24 and the AmpliPrep methods. The Nanogen PCR assay yielded higher mean CMV plasma DNA values than the Abbott and the Roche PCR assays, regardless of the platform used for DNA extraction. Overall, the effects of the extraction method and the QRT-PCR used on CMV plasma DNA load measurements were less pronounced for specimens with high CMV DNA content (>10,000 copies/ml). The performance characteristics of the extraction methods and QRT-PCR assays evaluated herein for clinical samples were extensible at cell-based standards from AcroMetrix. In conclusion, different automated systems are not equally efficient for CMV DNA extraction from plasma specimens, and the plasma CMV DNA loads measured by commercially available QRT-PCRs can differ significantly. The above findings should be taken into consideration for the establishment of cutoff values for the initiation or cessation of preemptive antiviral therapies and for the interpretation of data from clinical studies in the Allo-SCT setting.

[Multisite validation of CDT measurement by the %CDT TIA and the Tina Quant %CDT kits].

PubMed

Boehrer, J L; Cano, Y; Capolaghi, B; Desch, G; Dosbaa, I; Estepa, L; Hennache, B; Schellenberg, F

2007-01-01

The measurement of CDT (Carbohydrate Deficient Transferrin) is an essential biological tool in the diagnosis and follow-up of alcohol abuse. It is also employed as a marker of abstinence for the restitution of driving licences. However, the precision of measurement, and the between laboratory homogeneity of the results are still discussed. The ion exchange followed by immunodetermination of CDT is available in two products, the Tina Quant %CDT (Roche, Mannheim, Germany) and the %CDT TIA (Bio-Rad, Hercules, United States). This multicentre study was undertaken: 1) to evaluate the analytical characteristics of these kits and the homogeneity of the results from one laboratory to another, independently of the method used, 2) to validate the differences between the proposed normal values of both kits, 3) to study the possibility of using commercial control sera as external quality control. Four analytical systems were included in the study (Roche Modular/Hitachi 717, Beckman Coulter Immage and LX20, Dade Behring BNII). Determinations were carried out on pools of sera, commercial control sera, kit controls, and 30 serums of patients. These latter were also analyzed in capillary electrophoresis in order to establish correlations between the techniques. The calibrations were stable over one 2 weeks period. The repeatability of measurements spread out from 3,1% to 24,7%, for a mean value lower than 10%. The commercial control sera provided reliable results, with values adapted to a routine quality control use. The results of the Bio-Rad applications were lower by approximately 20% than those of the Roche application, which justifies the difference of the normal values (2,6% versus 3%), and an identical classification of the patients in at least 27 of the 30 samples. We conclude that the analytical quality of the compared techniques, even if it could be improved, is sufficient to guarantee a good reliability of the results. An external quality control could be proposed by using the control sera that we tested.

Stability and Evolution of Supernova Fallback Disks

NASA Astrophysics Data System (ADS)

Menou, Kristen; Perna, Rosalba; Hernquist, Lars

2001-10-01

We show that thin accretion disks made of carbon or oxygen are subject to the same thermal ionization instability as hydrogen and helium disks. We argue that the instability applies to disks of any metal content. The relevance of the instability to supernova fallback disks probably means that their power-law evolution breaks down when they first become neutral. We construct simple analytical models for the viscous evolution of fallback disks to show that it is possible for these disks to become neutral when they are still young (ages of a few 103 to 104 yr), compact in size (a few 109 to 1011 cm) and generally accreting at sub-Eddington rates (M~a few 1014-1018 g s-1). Based on recent results on the nature of viscosity in the disks of close binaries, we argue that this time may also correspond to the end of the disk activity period. Indeed, in the absence of a significant source of viscosity in the neutral phase, the entire disk will likely turn to dust and become passive. We discuss various applications of the evolutionary model, including anomalous X-ray pulsars and young radio pulsars. Our analysis indicates that metal-rich fallback disks around newly born neutron stars and black holes become neutral generally inside the tidal truncation radius (Roche limit) for planets at ~1011 cm. Consequently, the efficiency of the planetary formation process in this context will mostly depend on the ability of the resulting disk of rocks to spread via collisions beyond the Roche limit. It appears easier for the merger product of a doubly degenerate binary, whether it is a massive white dwarf or a neutron star, to harbor planets because its remnant disk has a rather large initial angular momentum, which allows it to spread beyond the Roche limit before becoming neutral. The early super-Eddington phase of accretion is a source of uncertainty for the disk evolution models presented here.

Pharmaceutical quality of seven generic Levodopa/Benserazide products compared with original Madopar® / Prolopa®.

PubMed

Gasser, Urs E; Fischer, Anton; Timmermans, Jan P; Arnet, Isabelle

2013-04-23

By definition, a generic product is considered interchangeable with the innovator brand product. Controversy exists about interchangeability, and attention is predominantly directed to contaminants. In particular for chronic, degenerative conditions such as in Parkinson's disease (PD) generic substitution remains debated among physicians, patients and pharmacists. The objective of this study was to compare the pharmaceutical quality of seven generic levodopa/benserazide hydrochloride combination products marketed in Germany with the original product (Madopar® / Prolopa® 125, Roche, Switzerland) in order to evaluate the potential impact of Madopar® generics versus branded products for PD patients and clinicians. Madopar® / Prolopa® 125 tablets and capsules were used as reference material. The generic products tested (all 100 mg/25 mg formulations) included four tablet and three capsule formulations. Colour, appearance of powder (capsules), disintegration and dissolution, mass of tablets and fill mass of capsules, content, identity and amounts of impurities were assessed along with standard physical and chemical laboratory tests developed and routinely practiced at Roche facilities. Results were compared to the original "shelf-life" specifications in use by Roche. Each of the seven generic products had one or two parameters outside the specifications. Deviations for the active ingredients ranged from +8.4% (benserazide) to -7.6% (levodopa) in two tablet formulations. Degradation products were measured in marked excess (+26.5%) in one capsule formulation. Disintegration time and dissolution for levodopa and benserazide hydrochloride at 30 min were within specifications for all seven generic samples analysed, however with some outliers. Deviations for the active ingredients may go unnoticed by a new user of the generic product, but may entail clinical consequences when switching from original to generic during a long-term therapy. Degradation products may pose a safety concern. Our results should prompt caution when prescribing a generic of Madopar®/Prolopa®, and also invite to further investigations in view of a more comprehensive approach, both pharmaceutical and clinical.

Performance of an Early Infant Diagnostic Test, AmpliSens DNA-HIV-FRT, Using Dried Blood Spots Collected from Children Born to Human Immunodeficiency Virus-Infected Mothers in Ukraine.

PubMed

Chang, Joy; Tarasova, Tetyana; Shanmugam, Vedapuri; Azarskova, Marianna; Nguyen, Shon; Hurlston, Mackenzie; Sabatier, Jennifer; Zhang, Guoqing; Osmanov, Saladin; Ellenberger, Dennis; Yang, Chunfu; Vitek, Charles; Liulchuk, Maria; Nizova, Natalya

2015-12-01

An accurate accessible test for early infant diagnosis (EID) is crucial for identifying HIV-infected infants and linking them to treatment. To improve EID services in Ukraine, dried blood spot (DBS) samples obtained from 237 HIV-exposed children (≤18 months of age) in six regions in Ukraine in 2012 to 2013 were tested with the AmpliSens DNA-HIV-FRT assay, the Roche COBAS AmpliPrep/COBAS TaqMan (CAP/CTM) HIV-1 Qual test, and the Abbott RealTime HIV-1 Qualitative assay. In comparison with the paired whole-blood results generated from AmpliSens testing at the oblast HIV reference laboratories in Ukraine, the sensitivity was 0.99 (95% confidence interval [CI], 0.95 to 1.00) for the AmpliSens and Roche CAP/CTM Qual assays and 0.96 (95% CI, 0.90 to 0.98) for the Abbott Qualitative assay. The specificity was 1.00 (95% CI, 0.97 to 1.00) for the AmpliSens and Abbott Qualitative assays and 0.99 (95% CI, 0.96 to 1.00) for the Roche CAP/CTM Qual assay. McNemar analysis indicated that the proportions of positive results for the tests were not significantly different (P > 0.05). Cohen's kappa (0.97 to 0.99) indicated almost perfect agreement among the three tests. These results indicated that the AmpliSens DBS and whole-blood tests performed equally well and were comparable to the two commercially available EID tests. More importantly, the performance characteristics of the AmpliSens DBS test meets the World Health Organization EID test requirements; implementing AmpliSens DBS testing might improve EID services in resource-limited settings. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Evaluation of the new restandardized Abbott Architect 25-OH Vitamin D assay in vitamin D-insufficient and vitamin D-supplemented individuals.

PubMed

Annema, Wijtske; Nowak, Albina; von Eckardstein, Arnold; Saleh, Lanja

2017-09-19

Recently, Abbott Diagnostics has restandardized the Architect 25(OH)D assay against the NIST SRM 2972. We have evaluated the analytical and clinical performance of the restandardized Architect 25(OH)D assay and compared its performance with a NIST-traceable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and the Roche total 25(OH)D assay in vitamin D-insufficient individuals before and after vitamin D 3 supplementation. Frozen serum samples were obtained from 88 healthy subjects with self-perceived fatigue and vitamin D-insufficiency <50 nmol L -1 who were randomized to receive a single 100 000 IU dose of vitamin D 3 (n = 48) or placebo (n = 40). Total 25(OH)D concentrations were measured before and 4 weeks after supplementation by the restandardized Architect 25(OH)D assay, LC-MS/MS, and Roche assay. The Architect 25(OH)D assay showed an intra- and inter-assay imprecision of <5%. Comparison of the Architect assay with the LC-MS/MS method showed a good correlation in both vitamin D-insufficient and vitamin D-supplemented subjects, however, with a negative mean bias of 17.4% and 8.9%, respectively. As compared to the Roche assay, the Abbott assay underestimated 25(OH)D results in insufficient subjects (<50 nmol L -1 ) with a mean negative bias of 17.1%, this negative bias turned into a positive bias in supplemented subjects. Overall there was a moderate agreement in classification of vitamin D-insufficient and -supplemented individuals into different vitamin D states between the Architect 25(OH)D method and LC-MS/MS. The routine use of the restandardized Architect 25(OH)D results in a slight underestimation of circulating total 25(OH)D levels at lower concentrations and thus potential misclassification of vitamin D status. © 2017 Wiley Periodicals, Inc.

A comparison of three apolipoprotein B methods and their associations with incident coronary heart disease risk over a 12-year follow-up period: The Multi-Ethnic Study of Atherosclerosis.

PubMed

Cao, Jing; Steffen, Brian T; Guan, Weihua; Remaley, Alan T; McConnell, Joseph P; Palamalai, Vikram; Tsai, Michael Y

Apolipoprotein B-100 (ApoB) is a well-researched lipoprotein marker used in assessing the risk of coronary heart disease (CHD) development. Despite its continued use at the bedside, ApoB methodologies have not been thoroughly compared and may differentially discriminate CHD risk, resulting in patient misclassification. This study compared 3 ApoB immunoassays and their associations with incident CHD risk over a 12-year follow-up period in the Multi-Ethnic Study of Atherosclerosis. Plasma ApoB concentrations were measured in 4679 participants of Multi-Ethnic Study of Atherosclerosis at baseline, using 3 immunoturbidimetric methods. Roche and Kamiya reagent-based methods were analyzed on a Roche modular P analyzer, and the Diazyme reagent-based method was analyzed on a Siemens Dimension analyzer. Cox proportional analysis estimated ApoB-related risk of incident CHD over a median follow-up period of 12.5 years with adjustments for nonlipid CHD risk factors. ApoB concentrations were examined as continuous variables but were also dichotomized based on clinical designations of borderline (100 mg/dL), high (120 mg/dL), and very high ApoB levels (140 mg/dL). Moderate to strong correlations among ApoB methods were observed (r = 0.79-0.98). ApoB concentrations (per standard deviation) were similarly associated with CHD risk and hazard ratio (95% confidence interval): Roche: 1.16 (1.03-1.30); Kamiya: 1.14 (1.02-1.28); and Diazyme: 1.14 (1.02-1.28). Although all 3 ApoB were similarly associated with risk of incident CHD over the study period regardless of the reagent type, the bias between methods suggests that these reagents are not fungible, and assay harmonization may be warranted. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Management of rosacea-prone skin: evaluation of a skincare product containing Ambophenol, Neurosensine, and La Roche-Posay Thermal spring water as monotherapy or adjunctive therapy.

PubMed

Seite, Sophie; Benech, Florence; Berdah, Sandrine; Bayer, Muriel; Veyrat, Sophie; Segot, Evelyne; Sakalikova, Marcela; Gibejova, Lucia; Zelenkova, Hana

2013-08-01

The objective of these studies was to investigate whether a skincare product containing Ambophenol, Neurosensine, and La Roche-Posay thermal spring water formulated in a highly protective packaging can have an impact in the management of rosacea-prone skin subjects. Several studies were performed to evaluate the efficacy of this product in the management of rosacea prone skin, as either monotherapy or adjunctive therapy or to maintain the efficacy of a Metronidazole treatment. The first study was performed on 37 women aged 18-45 with added stage 2 erythro-couperosis, who applied test formula as monotherapy twice a day for 4 weeks. During a second study, a dermatological evaluation was performed on patients with stage I or II rosacea, a questionnaire containing information about patient characteristics, tolerance, clinical signs, symptoms and skin reactivity to "trigger factors" was completed by dermatologists at baseline and 2 months after treatment with the test formula as either monotherapy or adjunctive therapy. Finally, in a third study, 65 patients finishing a Metronidazole treatment applied once daily and the tested formula twice daily were divided into 2 groups using the test formula or vehicle control, twice a day for 8 weeks for the evaluation of efficacy as adjunctive therapy. We noted that the test formula, as an adjunctive therapy, helped prolong the efficacy of a Metronidazole treatment. In monotherapy, there was a significant efficacy of the test formula associated with an excellent tolerance. A significant improvement of all the clinical signs and symptoms of rosacea and a reduction of the skin reactivity to "trigger factors" were shown. These studies highlight the interest value and impact of a skincare product containing Ambophenol, Neurosensine, and La Roche-Posay thermal spring water formulated in a highly protective packaging in monotherapy or in combination with or after a therapeutic treatment in the management of patients suffering from rosacea.

Diagnostic accuracy of the ROCHE Septifast PCR system for the rapid detection of blood pathogens in neonatal sepsis-A prospective clinical trial.

PubMed

Straub, Julia; Paula, Helga; Mayr, Michaela; Kasper, David; Assadian, Ojan; Berger, Angelika; Rittenschober-Böhm, Judith

2017-01-01

Diagnosis of neonatal sepsis remains a major challenge in neonatology. Most molecular-based methods are not customized for neonatal requirements. The aim of the present study was to assess the diagnostic accuracy of a modified multiplex PCR protocol for the detection of neonatal sepsis using small blood volumes. 212 episodes of suspected neonatal late onset sepsis were analyzed prospectively using the Roche SeptiFast® MGRADE PCR with a modified DNA extraction protocol and software-handling tool. Results were compared to blood culture, laboratory biomarkers and clinical signs of sepsis. Of 212 episodes, 85 (40.1%) were categorized as "not infected". Among these episodes, 1 was false positive by blood culture (1.2%) and 23 were false positive by PCR (27.1%). Of 51 (24.1%) episodes diagnosed as "culture proven sepsis", the same pathogen was detected by blood culture and PCR in 39 episodes (76.5%). In 8 episodes, more pathogens were detected by PCR compared to blood culture, and in 4 episodes the pathogen detected by blood culture was not found by PCR. One of these episodes was caused by Bacillus cereus, a pathogen not included in the PCR panel. In 76/212 (35.8%) episodes, clinical sepsis was diagnosed. Among these, PCR yielded positive results in 39.5% of episodes (30/76 episodes). For culture-positive sepsis, PCR showed a sensitivity of 90.2% (95%CI 86.2-94.2%) and a specificity of 72.9% (95%CI 67.0-79.0%). The Roche SeptiFast® MGRADE PCR using a modified DNA extraction protocol showed acceptable results for rapid detection of neonatal sepsis in addition to conventional blood culture. The benefit of rapid pathogen detection has to be balanced against the considerable risk of contamination, loss of information on antibiotic sensitivity pattern and increased costs.

Continuum viscoplastic simulation of a granular column collapse on large slopes : μ(I) rheology and lateral wall effects

NASA Astrophysics Data System (ADS)

Martin, Nathan; Mangeney, Anne; Ionescu, Ioan; Bouchut, Francois

2016-04-01

The description of the mechanical behaviour of granular flows and in particular of the static/flowing transition is still an open and challenging issue with strong implication for hazard assessment [{Delannay et al.}, 2016]. In particular, {detailed quantitative} comparison between numerical models and observations is necessary to go further in this direction. We simulate here dry granular flows resulting from the collapse of granular columns on an inclined channel (from horizontal to 22^o) and compare precisely the results with laboratory experiments performed by {Mangeney et al.} [2010] and {Farin et al.} [2014]. Incompressibility is assumed despite the dilatancy observed in the experiments (up to 10%). The 2-D model is based on the so-called μ(I) rheology that induces a Drucker-Prager yield stress and a variable viscosity. A nonlinear Coulomb friction term, representing the friction on the lateral walls of the channel is added to the model. We demonstrate that this term is crucial to accurately reproduce granular collapses on slopes higher than 10o whereas it remains of little effect on horizontal slope [{Martin et al.}, 2016]. We show that the use of a variable or a constant viscosity does not change significantly the results provided that these viscosities are of the same order [{Ionescu et al.}, 2015]. However, only a fine tuning of the constant viscosity (η = 1 Pa.s) makes it possible to predict the slow propagation phase observed experimentally on large slopes. This was not possible when using, without tuning, the variable viscosity calculated from the μ(I) rheology with the parameters estimated from experiments. Finally, we discuss the well-posedness of the model with variable and constant viscosity based in particular on the development of shear bands observed in the numerical simulations. References Delannay, R., Valance, A., Mangeney, A., Roche, O., and Richard, P., 2016. Granular and particle-laden flows: from laboratory experiments to field observations, {J. Phys. D: Appl. Phys.}, submitted. Farin, M., Mangeney, A., and Roche, O., 2014. Dynamics, deposit and erosion processes in granular collapse over sloping beds, {J. Geophys. Res. Earth Surf.}, 119(3), 504-532. Ionescu, I., Mangeney, A., Bouchut, F., and Roche, O., 2015. Viscoplastic modelling of granular column collapse with pressure and rate dependent viscosity, {J. Non-Newtonian Fluid Mech.}, 219, 1-18. Mangeney, A., Roche, O., Hungr, O., Mangold, Faccanoni, G., and Lucas, A., 2010. Erosion and mobility in granular collapse over sloping beds, {J. Geophys. Res.-Earth Surf.}, 115, F03040. Martin, N., Ionescu, I. R., Mangeney, A., Bouchut, F. and Farin, M., Continuum viscoplastic simulation of a granular column collapse on large slopes: μ(I) rheology and lateral wall effects, submitted.

Annotation-based genome-wide SNP discovery in the large and complex Aegilops tauschii genome using next-generation sequencing without a reference genome sequence

PubMed Central

2011-01-01

Background Many plants have large and complex genomes with an abundance of repeated sequences. Many plants are also polyploid. Both of these attributes typify the genome architecture in the tribe Triticeae, whose members include economically important wheat, rye and barley. Large genome sizes, an abundance of repeated sequences, and polyploidy present challenges to genome-wide SNP discovery using next-generation sequencing (NGS) of total genomic DNA by making alignment and clustering of short reads generated by the NGS platforms difficult, particularly in the absence of a reference genome sequence. Results An annotation-based, genome-wide SNP discovery pipeline is reported using NGS data for large and complex genomes without a reference genome sequence. Roche 454 shotgun reads with low genome coverage of one genotype are annotated in order to distinguish single-copy sequences and repeat junctions from repetitive sequences and sequences shared by paralogous genes. Multiple genome equivalents of shotgun reads of another genotype generated with SOLiD or Solexa are then mapped to the annotated Roche 454 reads to identify putative SNPs. A pipeline program package, AGSNP, was developed and used for genome-wide SNP discovery in Aegilops tauschii-the diploid source of the wheat D genome, and with a genome size of 4.02 Gb, of which 90% is repetitive sequences. Genomic DNA of Ae. tauschii accession AL8/78 was sequenced with the Roche 454 NGS platform. Genomic DNA and cDNA of Ae. tauschii accession AS75 was sequenced primarily with SOLiD, although some Solexa and Roche 454 genomic sequences were also generated. A total of 195,631 putative SNPs were discovered in gene sequences, 155,580 putative SNPs were discovered in uncharacterized single-copy regions, and another 145,907 putative SNPs were discovered in repeat junctions. These SNPs were dispersed across the entire Ae. tauschii genome. To assess the false positive SNP discovery rate, DNA containing putative SNPs was amplified by PCR from AL8/78 and AS75 and resequenced with the ABI 3730 xl. In a sample of 302 randomly selected putative SNPs, 84.0% in gene regions, 88.0% in repeat junctions, and 81.3% in uncharacterized regions were validated. Conclusion An annotation-based genome-wide SNP discovery pipeline for NGS platforms was developed. The pipeline is suitable for SNP discovery in genomic libraries of complex genomes and does not require a reference genome sequence. The pipeline is applicable to all current NGS platforms, provided that at least one such platform generates relatively long reads. The pipeline package, AGSNP, and the discovered 497,118 Ae. tauschii SNPs can be accessed at (http://avena.pw.usda.gov/wheatD/agsnp.shtml). PMID:21266061

Flow boundary conditions for chain-end adsorbing polymer blends.

PubMed

Zhou, Xin; Andrienko, Denis; Delle Site, Luigi; Kremer, Kurt

2005-09-08

Using the phenol-terminated polycarbonate blend as an example, we demonstrate that the hydrodynamic boundary conditions for a flow of an adsorbing polymer melt are extremely sensitive to the structure of the epitaxial layer. Under shear, the adsorbed parts (chain ends) of the polymer melt move along the equipotential lines of the surface potential whereas the adsorbed additives serve as the surface defects. In response to the increase of the number of the adsorbed additives the surface layer becomes thinner and solidifies. This results in a gradual transition from the slip to the no-slip boundary condition for the melt flow, with a nonmonotonic dependence of the slip length on the surface concentration of the adsorbed ends.

The Earth Gravitational Model 1996: The NCCS: Resource for Development, Resource for the Future

NASA Technical Reports Server (NTRS)

2002-01-01

For centuries, men have attempted to understand the climate system through observations obtained from Earth's surface. These observations yielded preliminary understanding of the ocean currents, tides, and prevailing winds using visual observation and simple mechanical tools as their instruments. Today's sensitive, downward-looking radar systems, called altimeters, onboard satellites can measure globally the precise height of the ocean surface. This surface is largely that of the equipotential gravity surface, called the geoid - the level surface to which the oceans would conform if there were no forces acting on them apart from gravity, as well as having a significant 1-2- meter-level signal arising from the motion of the ocean's currents.

Dimensional oscillation. A fast variation of energy embedding gives good results with the AMBER potential energy function.

PubMed

Snow, M E; Crippen, G M

1991-08-01

The structure of the AMBER potential energy surface of the cyclic tetrapeptide cyclotetrasarcosyl is analyzed as a function of the dimensionality of coordinate space. It is found that the number of local energy minima decreases as the dimensionality of the space increases until some limit at which point equipotential subspaces appear. The applicability of energy embedding methods to finding global energy minima in this type of energy-conformation space is explored. Dimensional oscillation, a computationally fast variant of energy embedding is introduced and found to sample conformation space widely and to do a good job of finding global and near-global energy minima.

Hybrid anodes for redox flow batteries

DOEpatents

Wang, Wei; Xiao, Jie; Wei, Xiaoliang; Liu, Jun; Sprenkle, Vincent L.

2015-12-15

RFBs having solid hybrid electrodes can address at least the problems of active material consumption, electrode passivation, and metal electrode dendrite growth that can be characteristic of traditional batteries, especially those operating at high current densities. The RFBs each have a first half cell containing a first redox couple dissolved in a solution or contained in a suspension. The solution or suspension can flow from a reservoir to the first half cell. A second half cell contains the solid hybrid electrode, which has a first electrode connected to a second electrode, thereby resulting in an equipotential between the first and second electrodes. The first and second half cells are separated by a separator or membrane.

Recent development of plasma optical systems (invited)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goncharov, A. A., E-mail: gonchar@iop.kiev.ua

2016-02-15

The article devotes a brief description of the recent development and current status of an ongoing research of plasma optical systems based on the fundamental plasma optical idea magnetic electron isolation, equipotentialization magnetic field lines, and the axi-symmetric cylindrical electrostatic plasma lens (PL) configuration. The experimental, theoretical, and simulation investigations have been carried out over recent years collaboratively between IP NASU (Kiev), LBNL (Berkeley, USA), and HCEI RAS (Tomsk). The crossed electric and magnetic fields inherent the PL configuration that provides the attractive method for establishing a stable plasma discharge at low pressure. Using PL configuration, several high reliability plasmamore » devices were developed. These devices are attractive for many high-tech applications.« less

Nonlinear Time Series Analysis via Neural Networks

NASA Astrophysics Data System (ADS)

Volná, Eva; Janošek, Michal; Kocian, Václav; Kotyrba, Martin

This article deals with a time series analysis based on neural networks in order to make an effective forex market [Moore and Roche, J. Int. Econ. 58, 387-411 (2002)] pattern recognition. Our goal is to find and recognize important patterns which repeatedly appear in the market history to adapt our trading system behaviour based on them.

Neural Stem Cell Delivery of Therapeutic Antibodies to Treat Breast Cancer Brain Metastases

DTIC Science & Technology

2010-10-01

Barry AM, MacKenzie LT, Mikulis DJ, Palmieri D, Bronder JL, Steeg PS, Yoneda T, MacDonald IC, Chambers AF, Rutt BK, Foster PJ: In vivo MRI of cancer...Fransisco, CA). Caspase-3 was immunoprecipitated from cell lysates in the presence of protease inhibitors (Roche complete Mini tablet , EDTA-free and 2

Global Analysis of Transcript and Protein Levels Across the Plasmodium falciparum Life Cycle

DTIC Science & Technology

2004-01-01

presence of 500 ng·mL1 pyrimethamine and gametocytogenesis was induced (Ifediba and Vanderberg 1981). N-acetyl-D- glucosamine (50 mM) was added to the...in 5 mM Tris(2-Carboxyethyl)phosphine hydrochloride (TCEP, Roche); (3) alkylated by 20 mM iodoacetamide (IAM); and (4) digested with proteinase K

Sandy Point Fun Run: A Context for Understanding and Using Scale

ERIC Educational Resources Information Center

Roche, Anne

2013-01-01

In the middle years of school, it is important that mathematics is challenging, engaging and focuses on worthwhile mathematics. In this article, Anne Roche describes a lesson that seemed to have all three of these characteristics, as students grappled with issues of scale to create a fun run, given a range of challenging mathematical constraints.…

Parameterization of Middle Atmospheric Water Vapor Photochemistry for High-Altitude NWP and Data Assimilation

DTIC Science & Technology

2008-01-01

Hood, L. L.: Solar- QBO in- teraction and its impact on stratospheric ozone in a zonally aver- aged photochemical transport model of the middle...Mon. Weather Rev., 132, 1254–1268, 2004. Randel, W. J., Wu, F., Russel, J. M., Roche, A., and Waters, J. W.: Seasonal cycles and QBO variations in

Waiting for 4.1

ERIC Educational Resources Information Center

Bernd, Karen

2003-01-01

What better way to clarify a topic and allow it to come alive than to provide students with a way to actually see it? Images, diagrams, and flowcharts can draw students in. In this article, the author reviews "Roche Genetics: Education Program" CD-ROM version 4.0. The program is organized using a theme park analogy. An information booth leads to a…

Effects of Proactive and Prosocial Behaviors on Critical Incidents of Schoolers from Lima

ERIC Educational Resources Information Center

Holguin Alvarez, Jhon A.

2017-01-01

The study focuses on the theoretical approaches of proactive and prosocial behavior of Covey (1996), Xifra (2009) and Roche-Olivar (2004), with the objective of analyzing the significant differences in the reduction of critical incidents in students from public and private schools in the district of San Juan de Lurigancho. To this end, two…

Breast EIT using a new projected image reconstruction method with multi-frequency measurements.

PubMed

Lee, Eunjung; Ts, Munkh-Erdene; Seo, Jin Keun; Woo, Eung Je

2012-05-01

We propose a new method to produce admittivity images of the breast for the diagnosis of breast cancer using electrical impedance tomography(EIT). Considering the anatomical structure of the breast, we designed an electrode configuration where current-injection and voltage-sensing electrodes are separated in such a way that internal current pathways are approximately along the tangential direction of an array of voltage-sensing electrodes. Unlike conventional EIT imaging methods where the number of injected currents is maximized to increase the total amount of measured data, current is injected only twice between two pairs of current-injection electrodes attached along the circumferential side of the breast. For each current injection, the induced voltages are measured from the front surface of the breast using as many voltage-sensing electrodes as possible. Although this electrode configurational lows us to measure induced voltages only on the front surface of the breast,they are more sensitive to an anomaly inside the breast since such an injected current tends to produce a more uniform internal current density distribution. Furthermore, the sensitivity of a measured boundary voltage between two equipotential lines on the front surface of the breast is improved since those equipotential lines are perpendicular to the primary direction of internal current streamlines. One should note that this novel data collection method is different from those of other frontal plane techniques such as the x-ray projection and T-scan imaging methods because we do not get any data on the plane that is perpendicular to the current flow. To reconstruct admittivity images using two measured voltage data sets, a new projected image reconstruction algorithm is developed. Numerical simulations demonstrate the frequency-difference EIT imaging of the breast. The results show that the new method is promising to accurately detect and localize small anomalies inside the breast.

Imperfect coupling between northern and southern ionospheres: asymmetry in TEC anomalies before earthquakes

NASA Astrophysics Data System (ADS)

Jhuang, Hau-Kun; Ho, Yi-Ying; Lee, Lou-Chuang

2016-04-01

The northern ionosphere is coupled to the conjugate southern ionosphere through the highly conducting geomagenetic field lines. The coupling is very strong or "perfect" if the geomagnetic field lines are equipotential (the parallel electric field E||=0) and hence the perpendicular electric field (E⊥) at the conjugate sites of both ionospheres are equal. The coupling is "imperfect" if some of the geomagnetic field lines are non-equipotential (E||≠0). The field-aligned electric field E|| can be associated with electron inertia, pressure gradient and collisions appearing in the form of double layer, kinetic Alfvén waves and finite field-aligned conductivity σ||. We use the Global Ionospheric Maps (GIM) data to examine the conjugate effect of total electron content (TEC) for six significant earthquakes. The anomalous (ΔTEC)source in the source ionosphere and (ΔTEC)conjugate in the conjugate ionosphere are obtained for 85 events before the six earthquakes. The ΔTEC ratio β = (ΔTEC)conjugate / (ΔTEC)source is calculated for each anomaly. For a "perfect" coupling, β=1. There are 85 anomalous events before the six significant earthquakes, with 62 events occurring in the daytime (07-18 LT) and 23 events in the nighttime (19-06 LT). The average value of daytime (07-18 LT) TEC variations in the source ionosphere is |ΔTEC|source =20.13 TECu, while the average value in the nighttime (19-06 LT) ionosphere is |ΔTEC|source=14.43 TECu. The value of ΔTEC ratio β ranges from 0.05 (very weak coupling) to 0.98 (nearly perfect coupling) with an average of 0.52. There are 14 strong coupling cases with β ≥0.8, which take place from 11 LT to 19 LT. The daytime (07-18 LT) β average value is 0.57 and the nighttime (19-06 LT) β average is 0.37. The south-north ionosphere coupling is stronger (weaker) in the daytime (nighttime).

A re-evaluation of the relativistic redshift on frequency standards at NIST, Boulder, Colorado, USA

NASA Astrophysics Data System (ADS)

Pavlis, Nikolaos K.; Weiss, Marc A.

2017-08-01

We re-evaluated the relativistic redshift correction applicable to the frequency standards at the National Institute of Standards and Technology (NIST) in Boulder, Colorado, USA, based on a precise GPS survey of three benchmarks on the roof of the building where these standards had been previously housed, and on global and regional geoid models supported by data from the GRACE and GOCE missions, including EGM2008, USGG2009, and USGG2012. We also evaluated the redshift offset based on the published NAVD88 geopotential number of the leveling benchmark Q407 located on the side of Building 1 at NIST, Boulder, Colorado, USA, after estimating the bias of the NAVD88 datum at our specific location. Based on these results, our current best estimate of the relativistic redshift correction, if frequency standards were located at the height of the leveling benchmark Q407 outside the second floor of Building 1, with respect to the EGM2008 geoid whose potential has been estimated to be {{W}0}=62 636 855.69 {{m}2} {{s}-2} , is equal to (-1798.50  ±  0.06)  ×  10-16. The corresponding value, with respect to an equipotential surface defined by the International Astronomical Union’s (IAU) adopted value of {{W}0}=62 636 856.0 {{m}2} {{s}-2} , is (-1798.53  ±  0.06)  ×  10-16. These values are comparable to the value of (-1798.70  ±  0.30)  ×  10-16, estimated by Pavlis and Weiss in 2003, with respect to an equipotential surface defined by {{W}0}=62 636 856.88 {{m}2} {{s}-2} . The minus sign implies that clocks run faster in the laboratory in Boulder than a corresponding clock located on the geoid. Contribution of US government, not subject to Copyright.

Relativistic Transverse Gravitational Redshift

NASA Astrophysics Data System (ADS)

Mayer, A. F.

2012-12-01

The parametrized post-Newtonian (PPN) formalism is a tool for quantitative analysis of the weak gravitational field based on the field equations of general relativity. This formalism and its ten parameters provide the practical theoretical foundation for the evaluation of empirical data produced by space-based missions designed to map and better understand the gravitational field (e.g., GRAIL, GRACE, GOCE). Accordingly, mission data is interpreted in the context of the canonical PPN formalism; unexpected, anomalous data are explained as similarly unexpected but apparently real physical phenomena, which may be characterized as ``gravitational anomalies," or by various sources contributing to the total error budget. Another possibility, which is typically not considered, is a small modeling error in canonical general relativity. The concept of the idealized point-mass spherical equipotential surface, which originates with Newton's law of gravity, is preserved in Einstein's synthesis of special relativity with accelerated reference frames in the form of the field equations. It was not previously realized that the fundamental principles of relativity invalidate this concept and with it the idea that the gravitational field is conservative (i.e., zero net work is done on any closed path). The ideal radial free fall of a material body from arbitrarily-large range to a point on such an equipotential surface (S) determines a unique escape-velocity vector of magnitude v collinear to the acceleration vector of magnitude g at this point. For two such points on S separated by angle dφ , the Equivalence Principle implies distinct reference frames experiencing inertial acceleration of identical magnitude g in different directions in space. The complete equivalence of these inertially-accelerated frames to their analogous frames at rest on S requires evaluation at instantaneous velocity v relative to a local inertial observer. Because these velocity vectors are not parallel, a symmetric energy potential exists between the frames that is quantified by the instantaneous Δ {v} = v\\cdot{d}φ between them; in order for either frame to become indistinguishable from the other, such that their respective velocity and acceleration vectors are parallel, a change in velocity is required. While the qualitative features of general relativity imply this phenomenon (i.e., a symmetric potential difference between two points on a Newtonian `equipotential surface' that is similar to a friction effect), it is not predicted by the field equations due to a modeling error concerning time. This is an error of omission; time has fundamental geometric properties implied by the principles of relativity that are not reflected in the field equations. Where b is the radius and g is the gravitational acceleration characterizing a spherical geoid S of an ideal point-source gravitational field, an elegant derivation that rests on first principles shows that for two points at rest on S separated by a distance d << b, a symmetric relativistic redshift exists between these points of magnitude z = gd2/bc^2, which over 1 km at Earth sea level yields z ˜{10-17}. It can be tested with a variety of methods, in particular laser interferometry. A more sophisticated derivation yields a considerably more complex predictive formula for any two points in a gravitational field.

[Examples of the keeping of drugs during the XVIth, XVIIth and XVIIIth centuries: silenes and drawers].

PubMed

Fievet, B

1998-01-01

Silenes are wooden boxes with colourful paintings for the keeping of drugs and can be found nowadays in three collections in France: Hotel-Dieu in Troyes (Aube), a pharmacy in Bauge (Maine-et-Loire) and St-Roch museum in Issoudun (Indre). Drawers can be related to silenes but they are more ordinary and less attractive.

Feasibility Analysis For Heating Tribal Buildings with Biomass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steve Clairmont; Micky Bourdon; Tom Roche

2009-03-03

This report provides a feasibility study for the heating of Tribal buildings using woody biomass. The study was conducted for the Confederated Salish and Kootenai Tribes of the Flathead Reservation in western Montana. S&K Holding Company and TP Roche Company completed the study and worked together to provide the final report. This project was funded by the DOE's Tribal Energy Program.

Defending the Freedom to Innovate: Faculty Intellectual Property Rights after "Stanford v. Roche"

ERIC Educational Resources Information Center

American Association of University Professors, 2014

2014-01-01

Tensions over faculty control of the fruits of their scholarship have been slowly building since the 1980s, but they have also intensified since late 2011. There have long been differences of opinion over ownership of patentable inventions, but over the last two years a number of universities have categorically asserted that they own these…

Datasets of Odontocete Sounds Annotated for Developing Automatic Detection Methods

DTIC Science & Technology

2010-12-01

Passive acoustic detection of Minke whales (Balaenoptera acutorostrata) off the West Coast of Kauai, HI. Book of abstracts, Fourth International...Workshop on Detection , Classification and Localization of Marine Mammals using Passive Acoustics , Pavia, Italy, Sept. 10- 13, 2009, p. 57. Roch, M., Y...Mellinger, and D. Gillespie. 2010. Comparison of beaked whale detection algorithms. Applied Acoustics 71:1043-1049. 8 References

Defining the transcriptome assembly and its use for genome dynamics and transcriptome profiling studies in pigeonpea (Cajanus cajan L.)

USDA-ARS?s Scientific Manuscript database

This study reports generation of large-scale genomic resources for pigeonpea, a so-called ‘orphan crop species’ of the semi-arid tropic regions. Roche FLX/454 sequencing was carried out on a normalized cDNA pool prepared from 31 tissues produced 494,353 short transcript reads (STRs). Cluster analysi...

Application of Cydia pomonella expressed sequence tags: identification and expression of three general odorant binding proteins in codling moth

USDA-ARS?s Scientific Manuscript database

The codling moth, Cydia pomonella, is one of the most important pests of pome fruits in the world, yet the molecular genetics and physiology of this insect remains poorly understood. A combined assembly of 8340 expressed sequence tags (ESTs) was generated from Roche 454 GS-FLX sequencing of 8 tissu...

SXR, A Novel Target for Breast Cancer Therapeutics

DTIC Science & Technology

2009-04-01

incubated overnight at 4°C with SXR (Anti-412, or PP-H4417, Perseus Proteomics inc., Japan) or p53 (FL- 393 HRP, Santa Cruz Biotechnology Inc., USA) antibod...min at 37°C in the presence of 0.1 U/ml nitrate reductase (from Aspergillus species, Roche), 50 μM NADPH (Sigma, USA) and 5 μM FAD (Sigma, USA). When

Comparative evaluation of the Aptima HIV-1 Quant Dx assay and COBAS TaqMan HIV-1 v2.0 assay using the Roche High Pure System for the quantification of HIV-1 RNA in plasma.

PubMed

Schalasta, Gunnar; Börner, Anna; Speicher, Andrea; Enders, Martin

2016-03-01

Quantification of human immunodeficiency virus type 1 (HIV-1) RNA in plasma has become the standard of care in the management of HIV-infected patients. There are several commercially available assays that have been implemented for the detection of HIV-1 RNA in plasma. Here, the new Hologic Aptima® HIV-1 Quant Dx assay (Aptima HIV) was compared to the Roche COBAS® TaqMan® HIV-1 Test v2.0 for use with the High Pure System (HPS/CTM). The performance characteristics of the assays were assessed using commercially available HIV reference panels, dilution of the WHO 3rd International HIV-1 RNA International Standard (WHO-IS) and plasma from clinical specimens. Assay performance was determined by linear regression, Deming correlation analysis and Bland-Altman analysis. Testing of HIV-1 reference panels revealed excellent agreement. The 61 clinical specimens quantified in both assays were linearly associated and strongly correlated. The Aptima HIV assay offers performance comparable to that of the HPS/CTM assay and, as it is run on a fully automated platform, a significantly improved workflow.

Atlantic salmon skin and fillet color changes effected by perimortem handling stress, rigor mortis, and ice storage.

PubMed

Erikson, U; Misimi, E

2008-03-01

The changes in skin and fillet color of anesthetized and exhausted Atlantic salmon were determined immediately after killing, during rigor mortis, and after ice storage for 7 d. Skin color (CIE L*, a*, b*, and related values) was determined by a Minolta Chroma Meter. Roche SalmoFan Lineal and Roche Color Card values were determined by a computer vision method and a sensory panel. Before color assessment, the stress levels of the 2 fish groups were characterized in terms of white muscle parameters (pH, rigor mortis, and core temperature). The results showed that perimortem handling stress initially significantly affected several color parameters of skin and fillets. Significant transient fillet color changes also occurred in the prerigor phase and during the development of rigor mortis. Our results suggested that fillet color was affected by postmortem glycolysis (pH drop, particularly in anesthetized fillets), then by onset and development of rigor mortis. The color change patterns during storage were different for the 2 groups of fish. The computer vision method was considered suitable for automated (online) quality control and grading of salmonid fillets according to color.

Simultaneous detection of human mitochondrial DNA and nuclear-inserted mitochondrial-origin sequences (NumtS) using forensic mtDNA amplification strategies and pyrosequencing technology.

PubMed

Bintz, Brittania J; Dixon, Groves B; Wilson, Mark R

2014-07-01

Next-generation sequencing technologies enable the identification of minor mitochondrial DNA variants with higher sensitivity than Sanger methods, allowing for enhanced identification of minor variants. In this study, mixtures of human mtDNA control region amplicons were subjected to pyrosequencing to determine the detection threshold of the Roche GS Junior(®) instrument (Roche Applied Science, Indianapolis, IN). In addition to expected variants, a set of reproducible variants was consistently found in reads from one particular amplicon. A BLASTn search of the variant sequence revealed identity to a segment of a 611-bp nuclear insertion of the mitochondrial control region (NumtS) spanning the primer-binding sites of this amplicon (Nature 1995;378:489). Primers (Hum Genet 2012;131:757; Hum Biol 1996;68:847) flanking the insertion were used to confirm the presence or absence of the NumtS in buccal DNA extracts from twenty donors. These results further our understanding of human mtDNA variation and are expected to have a positive impact on the interpretation of mtDNA profiles using deep-sequencing methods in casework. © 2014 American Academy of Forensic Sciences.

Polar hysteria: an expression of hypervitaminosis A.

PubMed

O'Donnell, James

2004-01-01

Isotretinoin (Accutane) is a drug closely related to the chemical structure of Vitamin A. The pharmacology and toxicology of these two retinoids is similar enough to warrant comparison. Accutane is a powerful drug which its manufacturer, Roche, indicates is limited for severe recalcitrant nodular acne. This potency is also reflected in Accutane's well-known ability to produce severe birth defects if taken during pregnancy. Less well-known is the risk of this lipid soluble chemical to affect the Central Nervous System. Reports of intracranial hypertension, depression, and suicidal indeation with Accutane use have prompted an examination of this serious and life threatening potential. Though Roche has added a warning to its product label for signs of depression and suicidal ideation, this product is being overprescribed for all forms of acne, including mild cases and moderate acne that have not been treated with alternative medications, which have a lesser risk of depression and suicide. There is no contesting that this drug is effective at clearing up the most severe forms of acne, but the public must be informed of its proper, limited indication for use; depression and suicide can follow in patients with no prior history of psychiatric symptoms or suicide attempts.

A Variant of the Mukai Pairing via Deformation Quantization

NASA Astrophysics Data System (ADS)

Ramadoss, Ajay C.

2012-06-01

Let X be a smooth projective complex variety. The Hochschild homology HH•( X) of X is an important invariant of X, which is isomorphic to the Hodge cohomology of X via the Hochschild-Kostant-Rosenberg isomorphism. On HH•( X), one has the Mukai pairing constructed by Caldararu. An explicit formula for the Mukai pairing at the level of Hodge cohomology was proven by the author in an earlier work (following ideas of Markarian). This formula implies a similar explicit formula for a closely related variant of the Mukai pairing on HH•( X). The latter pairing on HH•( X) is intimately linked to the study of Fourier-Mukai transforms of complex projective varieties. We give a new method to prove a formula computing the aforementioned variant of Caldararu's Mukai pairing. Our method is based on some important results in the area of deformation quantization. In particular, we use part of the work of Kashiwara and Schapira on Deformation Quantization modules together with an algebraic index theorem of Bressler, Nest and Tsygan. Our new method explicitly shows that the "Noncommutative Riemann-Roch" implies the classical Riemann-Roch. Further, it is hoped that our method would be useful for generalization to settings involving certain singular varieties.

Resonant Tidal Forcing in Close Binaries: Implications for CVs

NASA Astrophysics Data System (ADS)

Ford, K. E. Saavik; McKernan, Barry; Schwab, Elliana

2018-01-01

Resonant tidal forcing occurs when the tidal forcing frequency of a binary matches a quadrupolar oscillation mode of one of the binary members and energy is transferred from the orbit of the binary to the mode. Tidal locking permits ongoing resonant driving of modes even as binary orbital parameters change. At small binary separations during tidal lock, a significant fraction of binary orbital energy can be deposited quickly into a resonant mode and the binary decays faster than via the emission of gravitational radiation alone. Here we discuss some of the implications of resonant tidal forcing for the class of binaries known as Cataclysmic Variable (CV) stars. We show that resonant tidal forcing of the donor’s Roche lobe could explain the observed 2‑3hr period gap in CVs, assuming modest orbital eccentricities are allowed (eb ∼ 0.03), and can be complementary or an alternative to, existing models. Sudden collapse of the companion orbit, yielding a Type Ia supernova is disfavoured, since Hydrogen is not observed in Type Ia supernova spectra. Therefore, resonance must generally be truncated, probably via mass loss from the Roche lobe or orbital perturbation, ultimately producing a short period CV containing an ’overheated’ white dwarf.

Reconstruction of electrocardiogram using ionic current models for heart muscles.

PubMed

Yamanaka, A; Okazaki, K; Urushibara, S; Kawato, M; Suzuki, R

1986-11-01

A digital computer model is presented for the simulation of the electrocardiogram during ventricular activation and repolarization (QRS-T waves). The part of the ventricular septum and the left ventricular free wall of the heart are represented by a two dimensional array of 730 homogeneous functional units. Ionic currents models are used to determine the spatial distribution of the electrical activities of these units at each instant of time during simulated cardiac cycle. In order to reconstruct the electrocardiogram, the model is expanded three-dimensionally with equipotential assumption along the third axis and then the surface potentials are calculated using solid angle method. Our digital computer model can be used to improve the understanding of the relationship between body surface potentials and intracellular electrical events.

Preliminary design of the thermal protection system for solar probe

NASA Technical Reports Server (NTRS)

Dirling, R. B., Jr.; Loomis, W. C.; Heightland, C. N.

1982-01-01

A preliminary design of the thermal protection system for the NASA Solar Probe spacecraft is presented. As presently conceived, the spacecraft will be launched by the Space Shuttle on a Jovian swing-by trajectory and at perihelion approach to three solar radii of the surface of the Earth's sun. The system design satisfies maximum envelope, structural integrity, equipotential, and mass loss/contamination requirements by employing lightweight carbon-carbon emissive shields. The primary shield is a thin shell, 15.5-deg half-angle cone which absorbs direct solar flux at up to 10-deg off-nadir spacecraft pointing angles. Secondary shields of sandwich construction and low thickness-direction thermal conductivity are used to reduce the primary shield infrared radiation to the spacecraft payload.

Electrowetting on a lotus leaf

PubMed Central

Feng, Jiang-Tao; Wang, Feng-Chao; Zhao, Ya-Pu

2009-01-01

Electrowetting on dielectrics has been widely used to manipulate and control microliter or nanoliter liquids in micro-total-analysis systems and laboratory on a chip. We carried out experiments on electrowetting on a lotus leaf, which is quite different from the equipotential plate used in conventional electrowetting. This has not been reported in the past. The lotus leaf is superhydrophobic and a weak conductor, so the droplet can be easily actuated on it through electrical potential gradient. The capillary motion of the droplet was recorded by a high-speed camera. The droplet moved toward the counterelectrode to fulfill the actuation. The actuation speed could be of the order of 10 mm∕s. The actuation time is of the order of 10 ms. PMID:19693341

DIN 1.7035 Steel Modification with High Intensity Nitrogen Ion Implantation

NASA Astrophysics Data System (ADS)

Ryabchikov, A. I.; Sivin, D. O.; Anan'in, P. S.; Ivanova, A. I.; Uglov, V. V.; Korneva, O. S.

2018-06-01

The paper presents research results on the formation of deep ion-modified layers of the grade DIN 1.7035 alloy steel due to a high intensity, repetitively-pulsed nitrogen ion beams with the ion current density of up to 0.5 A/cm2. The formation of a low-energy, high intensity nitrogen ion beam is based on a plasma immersion ion extraction followed by the ballistic focusing in the equipotential drift region. The nitrogen ion implantation in steel specimens is performed at a 1.2 keV energy and 450, 500, 580 and 650°C temperatures during 60 minutes. The morphology, elementary composition and mechanical properties are investigated in deep layers of steel specimens alloyed with nitrogen ions.

Enhancement of Anti-Telomerase Immunity Against Prostate Cancer

DTIC Science & Technology

2007-11-01

patients, a separate clinical trial has been designed. ATRA in capsules ( Tretinoin ) was given to patients for 7 consecutive days. After ATRA...Calbiochem (La Jolla, CA). Tetanus toxoid was purchased from List Biological Labs (Campbell, CA). ATRA ( Tretinoin ) was obtained from Roche Pharmaceuticals...patients with Tretinoin (ATRA) in combination with cancer vaccine. To evaluate whether in vivo ATRA treatment could diminish immune suppression mediated by

Effects of Stress and Nicotine on Cognitive Function in Male and Female Rats

DTIC Science & Technology

2016-05-20

abnormal psychology 109:188-97 84. Shih RA, Glass TA, Bandeen-Roche K, Carlson MC, Bolla KI, et al. 2006. Environmental lead exposure and cognitive...submitted to the Faculty of the Medical and Clinical Psychology Graduate Program Uniformed Services University of the Health Sciences In partial...Molecular & Cell Biology -Neuroscience Departmental -Cli.nical Psychology -Environmental Health Sciences -Medical Psychology -Medical Zoology

Identification of Two New Protective Pre-erythrocytic Malaria Vaccine Antigen Candidates

DTIC Science & Technology

2011-01-01

Anthony R, Grainger M, Haynes J, Moch J, Muster N, Sacci J, Tabb D, Witney A, Wolters D, Wu Y, Gardner M, Holder A, Sinden R, Yates J, Carucci D: A...proteomic view of the Plasmodium falciparum life cycle. Nature 2002, 419:520-526. 16. LeRoch D, Zhou Y, Blair P, Grainger M, Moch J, Haynes J, De La Vega P

Do Items that Measure Self-Perceived Physical Appearance Function Differentially across Gender Groups? An Application of the MACS Model

ERIC Educational Resources Information Center

Gonzalez-Roma, Vicente; Tomas, Ines; Ferreres, Doris; Hernandez, Ana

2005-01-01

The aims of this study were to investigate whether the 6 items of the Physical Appearance Scale (Marsh, Richards, Johnson, Roche, & Tremayne, 1994) show differential item functioning (DIF) across gender groups of adolescents, and to show how this can be done using the multigroup mean and covariance structure (MG-MACS) analysis model. Two samples…

D-Amino Acids Enhance the Activity of Antimicrobials against Biofilms of Clinical Wound Isolates of Staphylococcus aureus and Pseudomonas aeruginosa

DTIC Science & Technology

2014-05-19

and P. aeruginosa biofilms. Screening of dispersive activity of individual D-amino acids, D-methionine (D-Met), D- phenylalanine (D-Phe), and D...Microb. Ecol. http://dx.doi.org/10.1007/s00248 -013-0297-x. 16. Roche ED, Renick PJ, Tetens SP, Ramsay SJ, Daniels EQ, Carson DL . 2012. Increasing the

Pharmaceutical quality of seven generic Levodopa/Benserazide products compared with original Madopar® / Prolopa®

PubMed Central

2013-01-01

Background By definition, a generic product is considered interchangeable with the innovator brand product. Controversy exists about interchangeability, and attention is predominantly directed to contaminants. In particular for chronic, degenerative conditions such as in Parkinson’s disease (PD) generic substitution remains debated among physicians, patients and pharmacists. The objective of this study was to compare the pharmaceutical quality of seven generic levodopa/benserazide hydrochloride combination products marketed in Germany with the original product (Madopar® / Prolopa® 125, Roche, Switzerland) in order to evaluate the potential impact of Madopar® generics versus branded products for PD patients and clinicians. Methods Madopar® / Prolopa® 125 tablets and capsules were used as reference material. The generic products tested (all 100 mg/25 mg formulations) included four tablet and three capsule formulations. Colour, appearance of powder (capsules), disintegration and dissolution, mass of tablets and fill mass of capsules, content, identity and amounts of impurities were assessed along with standard physical and chemical laboratory tests developed and routinely practiced at Roche facilities. Results were compared to the original “shelf-life” specifications in use by Roche. Results Each of the seven generic products had one or two parameters outside the specifications. Deviations for the active ingredients ranged from +8.4% (benserazide) to −7.6% (levodopa) in two tablet formulations. Degradation products were measured in marked excess (+26.5%) in one capsule formulation. Disintegration time and dissolution for levodopa and benserazide hydrochloride at 30 min were within specifications for all seven generic samples analysed, however with some outliers. Conclusions Deviations for the active ingredients may go unnoticed by a new user of the generic product, but may entail clinical consequences when switching from original to generic during a long-term therapy. Degradation products may pose a safety concern. Our results should prompt caution when prescribing a generic of Madopar®/Prolopa®, and also invite to further investigations in view of a more comprehensive approach, both pharmaceutical and clinical. PMID:23617953

Evaluation of the effects of insufficient blood volume samples on the performance of blood glucose self-test meters.

PubMed

Pfützner, Andreas; Schipper, Christina; Ramljak, Sanja; Flacke, Frank; Sieber, Jochen; Forst, Thomas; Musholt, Petra B

2013-11-01

Accuracy of blood glucose readings is (among other things) dependent on the test strip being completely filled with sufficient sample volume. The devices are supposed to display an error message in case of incomplete filling. This laboratory study was performed to test the performance of 31 commercially available devices in case of incomplete strip filling. Samples with two different glucose levels (60-90 and 300-350 mg/dl) were used to generate three different sample volumes: 0.20 µl (too low volume for any device), 0.32 µl (borderline volume), and 1.20 µl (low but supposedly sufficient volume for all devices). After a point-of-care capillary reference measurement (StatStrip, NovaBiomedical), the meter strip was filled (6x) with the respective volume, and the response of the meters (two devices) was documented (72 determinations/meter type). Correct response was defined as either an error message indicating incomplete filling or a correct reading (±20% compared with reference reading). Only five meters showed 100% correct responses [BGStar and iBGStar (both Sanofi), ACCU-CHEK Compact+ and ACCU-CHEK Mobile (both Roche Diagnostics), OneTouch Verio (LifeScan)]. The majority of the meters (17) had up to 10% incorrect reactions [predominantly incorrect readings with sufficient volume; Precision Xceed and Xtra, FreeStyle Lite, and Freedom Lite (all Abbott); GlucoCard+ and GlucoMen GM (both Menarini); Contour, Contour USB, and Breeze2 (all Bayer); OneTouch Ultra Easy, Ultra 2, and Ultra Smart (all LifeScan); Wellion Dialog and Premium (both MedTrust); FineTouch (Terumo); ACCU-CHEK Aviva (Roche); and GlucoTalk (Axis-Shield)]. Ten percent to 20% incorrect reactions were seen with OneTouch Vita (LifeScan), ACCU-CHEK Aviva Nano (Roche), OmniTest+ (BBraun), and AlphaChek+ (Berger Med). More than 20% incorrect reactions were obtained with Pura (Ypsomed), GlucoCard Meter and GlucoMen LX (both Menarini), Elite (Bayer), and MediTouch (Medisana). In summary, partial and incomplete blood filling of glucose meter strips is often associated with inaccurate reading. These findings underline the importance of appropriate patient education on this aspect of blood glucose self-monitoring. © 2013 Diabetes Technology Society.

PHOTOMETRIC PROPERTIES FOR SELECTED ALGOL-TYPE BINARIES. II. AO SERPENTIS AND V338 HERCULIS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Y.-G.; Dai, H.-F.; Hu, S.-M.

2010-04-15

We present the first multiband photometry for the semidetached eclipsing binary AO Serpentis, observed on seven nights between 2009 April and July at the Weihai Observatory of Shandong University. By using the 2003 version of the Wilson-Devinney code, the photometric solutions of AO Ser and a similar object V338 Her were (re)deduced. The spectral types and orbital periods are A2 and P = 0.8793 days for AO Ser, F1V and P = 1.3057 days for V338 Her. The results reveal that two binaries are low mass ratio systems, whose secondary components fill their Roche lobes. The fill-out factors of themore » primary components are f = 58.6% for AO Ser and f = 54.2% for V338 Her, respectively. From the O - C curves of AO Ser and V338 Her, it is discovered that secular period changes with cyclic variations exist. The periods and semiamplitudes are 17.32({+-}0.01) yr and 0.0051({+-}0.0001) days for AO Ser, 29.07({+-}0.04) yr and 0.0116({+-}0.0015) days for V338 Her, respectively. This kind of cyclic oscillation may be attributed to either the light-time effect via an assumed third body or perhaps cyclic magnetic activity on the secondary component. For AO Ser, the long-term period decreases at a rate of dP/dt = -5.35({+-}0.03) x 10{sup -7} days yr{sup -1}, which may be caused by mass and angular momentum loss from the system. Considering the period decreasing, the fill-out factor of the primary for AO Ser will increase and it will finally fill its Roche lobe. Meanwhile, the secular period increase rate for V338 Her is dP/dt = +1.44({+-}0.24) x 10{sup -7} days yr{sup -1}, indicating that mass transfers from the less massive component to the more massive component. This will also cause the fill-out factor of the primary to increase. When the primaries fill their Roche lobes, AO Ser and V338 Her may evolve into contact stars, as predicted by the theory of thermal relaxation oscillations.« less

Multi-center validation of the Response Biomedical Corporation RAMP NT-proBNP assay with comparison to the Roche Diagnostics GmbH Elecsys proBNP assay.

PubMed

Lee-Lewandrowski, Elizabeth; Januzzi, James L; Green, Sandy M; Tannous, Bakhos; Wu, Alan H B; Smith, Andrew; Wong, Alicia; Murakami, MaryAnn M; Kaczmarek, Jason; Apple, Fred S; Miller, Wayne L; Hartman, Karen; Jaffe, Allan S

2007-01-01

NT-proBNP measurements aid in the evaluation of patients with suspected heart failure (HF) and may facilitate risk stratification in patients with HF and acute coronary syndrome (ACS). Point-of-care (POC) assays may provide more timely results and potentially improve patient outcomes. We evaluated the analytical performance of the Response Biomedical Corporation whole blood RAMP amino-terminal pro-B type natriuretic peptide (NT-proBNP) POC assay compared to the Roche Elecsys proBNP (NT-proBNP) assay. Intra-day and total imprecision (% CV) ranged from 5.5% to 10.3% at 140, 449 and 1675 ng/L. The lowest concentration that yields a 20% CV was 57 ng/L. The lower limit of detection was 18 ng/L. The upper limit of linearity was validated to 23,428 ng/L with an average recovery of 95%. Correlation by Passing and Bablok regression yielded RAMP=1.01 Elecsys+14.6, r=0.98 (n=540; range of Elecsys values <5 to >35,000). Concordance of RAMP versus Elecsys using cut-offs of 125 ng/L for subjects <75 years and 450 ng/L for subjects > or =75 was 92% (95% CI 89-94%) for a group consisting of 127 apparently healthy individuals and 208 non-healthy subjects without HF, and 99% (95% CI 97-100%) for patients with HF, using the New York Heart Association (NYHA) functional classification. Overall, 80%, 87%, 97% and 100% of the RAMP results and 77%, 85%, 96% and 100% of the Elecsys results were greater than the age appropriate cut-off for NYHA I, II, III or IV groups. For both the RAMP and Elecsys results, the median NT-proBNP value was statistically correlated (increasing) with NYHA I, II, III or IV groups, respectively (p<0.0001), with no significant difference between the two methods. The POC Response Biomedical RAMP NT-proBNP assay provides comparable results that measured on the FDA cleared Roche Elecsys central laboratory platform.

Mind the Gap when Data Mining the Ritter-Kolb Cataclysmic Variable Catalogue

NASA Astrophysics Data System (ADS)

Sparks, Warren M.; Sion, Edward M.

2017-01-01

The cataclysmic variable (CV) binary consists of a white dwarf primary and a low-mass secondary which overflows its Roche lobe. The Ritter-Kolb catalogue (2003, A&A, 404, 301) is a collection (~1000) of CV binaries and related objects. We have mined this catalogue for CVs with unevolved secondaries whose mass ratio (secondary/primary) is known (~130). A plot of the secondary mass verses the log of the orbital period exhibits the well-known period gap at 2-3 hrs. In addition, this plot shows that the secondary masses just above the period gap are collectively much larger than those just below. The average of the first ten secondary masses above the period is 180% larger than the average below the gap.The disrupted magnetic braking hypothesis (Howell, Nelson, and Rappaport 2001, ApJ, 550, 897 [HNR]) predicts that when the secondary becomes fully convective, the magnetic braking, which has driven the secondary out of thermal equilibrium, stops. In adjusting to thermal equilibrium the secondary shrinks below its Roche lobe and no longer loses mass. The binary system ceases to appear as a CV until gravitational radiation loss brings the secondary back in contact with its Roche lobe. This scenario is at odds with the apparent secondary mass loss across the period gap. Either the secondary continues to lose mass while crossing the period gap or the secondary masses are miscalculated!Magnetic braking causes the secondary to expand or inflate larger than its single star counterpart. Any orbital parameter calculation which assumes a radius-mass relationship based on single main-sequence stars will overestimate the mass of the secondary. We can approximate this mass overestimation from calculations by HNR which take into account the thermal heating from magnetic braking. Using this approximation as a first-order correction to the secondary mass, we replot the deflated secondary mass versus the binary period. The deflated masses immediately above and below the period gap are similar and do not indicate secondary mass loss across the gap. Thus, magnetic braking not only explains the period gap but the apparent secondary mass shift across it. Orbital parameters must be based upon actual secondary mass-radius observations.

Forming Inner Ice-Rich Moons at Saturn from a Massive Early Ring

NASA Astrophysics Data System (ADS)

Salmon, Julien; Canup, Robin M.

2014-11-01

Saturn’s rings are 90 to 95% water ice. As a group, Saturn’s moons interior to and including Tethys are also about 90% ice. The small inner moons (interior to and including Janus) are dynamically young with histories tied to that of the rings (e.g., Goldreich & Tremaine 1982; Esposito 1986). Charnoz et al. (2010) showed that ring material viscously spreading outward across the Roche limit can produce these small moons and their observed mass vs. distance relationship within the last 107 years. Canup (2010) proposed that at the end of Saturn’s formation, tidal stripping from a differentiated Titan-sized moon as it spiraled into Saturn could have produced a massive 1024 - 1025 g initial ice ring, and that Mimas, Enceladus and Tethys could have been similarly spawned from this primordial ring as it viscously evolved. Charnoz et al. (2011) considered a massive ice-rock ring and a tidal dissipation factor for Saturn of Q ˜ 103, and found that satellites out to Rhea could be spawned from such a ring. However the likelihood of such a small value for Q is debated. In addition, capture into mutual mean motion resonances and resulting eccentricity growth (not included in the Charnoz et al. model) could lead to orbital destabilization as the moons tidally expand over large distances (Peale & Canup 2014). Here we consider a dissipation factor for Saturn Q ˜ 104 - 105 and investigate whether Mimas, Enceladus and Tethys could have been spawned from a massive initial ice ring. In this scenario, the rock in these moons would be delivered by material from outside the rings, e.g. by heliocentric impactors during the LHB (Canup 2013). We have expanded a numerical model developed to study the accretion of Earth's Moon (Salmon and Canup 2012, 2014), which couples an analytic Roche-interior disk model to the N-body code SyMBA for material exterior to the Roche limit, so that we can directly track the accretion and mutual interactions of growing satellites (including mean-motion resonances) as well as their tidal interaction with the planet. Implications for the origin and early dynamical evolution of Saturn’s inner moons will be discussed.

Chronological constraints on the Holocene glacier dynamics of the Argentière Glacier (Mont Blanc massif, France) based on cosmogenic nuclide dating

NASA Astrophysics Data System (ADS)

Protin, Marie; Schimmelpfennig, Irene; Mugnier, Jean-Louis; Ravanel, Ludovic; Deline, Philip; Le Roy, Melaine; Moreau, Luc; Aster Team

2017-04-01

While reconstruction of glacier fluctuations during the Holocene provides important information about the glacier response to natural climate change, it is still a challenge to accurately constrain chronologies of past glacier advances and retreats. Moraine deposits and roches moutonnées represent valuable geomorphic markers of advanced glacier extensions, while the currently ongoing glacier melt uncovers proglacial bedrock that can be used as a new archive to investigate the durations when a glacier was in retreated position during the Holocene. Our study focuses on the Mont-Blanc massif (MBM), located in the Western Alps and hosting some of the largest glaciers of Europe. Chronologies of Holocene glacier fluctuations in this area are still sparse, even if recent studies considerably improved the temporal reconstruction of Holocene advances of some glaciers in the MBM and locations near-by (e.g. Le Roy et al., 2015). Here we present preliminary 10Be exposure ages obtained from moraine boulders, roches moutonnées and pro- and subglacial bedrock in the area of the Argentière Glacier, located on the north-western flank of the MBM. The ages of moraine boulders and roche moutonnée surfaces outboard of the investigated moraines suggest that the Early Holocene deglaciation of this area started around 11 ka ago. Also, 10Be measurements of recently deglaciated bedrock surfaces indicate that the glacier was at a position at least as retracted as today for a minimum duration of 7 ka throughout the Holocene. The 10Be measurement of one sample from a surface that is currently still covered by 60 m of ice suggests that the glacier was shorter than today for at least a duration of 3 ka. These first results will soon be completed with in situ 14C measurements, which will allow us to quantify and take into account subglacial erosion rates and thus to more accurately determine the cumulative duration of pro- and subglacial bedrock exposure during the Holocene.

Evaluation of the Cobas TaqMan MTB Test for the Detection of Mycobacterium tuberculosis Complex According to Acid-Fast-Bacillus Smear Grades in Respiratory Specimens

PubMed Central

Huh, Hee Jae; Koh, Won-Jung; Song, Dong Joon

2014-01-01

We evaluated the performance of the Cobas TaqMan MTB test (Roche Diagnostics, Basel, Switzerland), stratified by acid-fast bacilli (AFB) smear grades. The sensitivity of this test in smear-positive specimens was >95% in all grades, while that in trace and negative specimens was 85.3% and 34.4%, respectively. PMID:25428157

Analytical and clinical comparison of Elecsys syphilis (Roche®) - Architect syphilis TP and reformulated Architect syphilis TP (Abbott®) assay.

PubMed

De Keukeleire, Steven; Desmet, Stefanie; Lagrou, Katrien; Oosterlynck, Julie; Verhulst, Manon; Van Besien, Jessica; Saegeman, Veroniek; Reynders, Marijke

2017-03-01

The performance of Elecsys Syphilis was compared to Architect Syphilis TP and Reformulated Architect Syphilis TP. The overall sensitivity and specificity were 98.4% and 99.5%, 97.7% and 97.1%, and 99.2% and 99.7% respectively. The assays are comparable and considered adequate for syphilis screening. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of a Hypocretin/Orexin Antagonist on Neurocognitive Performance

DTIC Science & Technology

2015-11-01

somnolence without cataplexy and, in rat, decreases active wake and increases the time spent in non-rapid eye movement (NREM) and (REM) sleep (Brisbare-Roch...system results in a narcoleptic phenotype characterized by excessive sleepiness, fragmented sleep, abnormally timed Rapid- Eye -Movement (REM) sleep, and...spent in non-rapid eye movement (NREM) and (REM) sleep with differential effects on various neurotransmitter systems. To date, no studies have reported

European Science Notes. Volume 39, Number 6.

DTIC Science & Technology

1985-06-01

recently, in the Roche Research Department to prepare plant science; and (2) to provide an in- probes for gene isolation and modifica- ternational...projects are carried out at the insti- ciated with the growth of axons and den- tute: gene expression in yeast; plant drites in the developing brain...synaptic junction of storage proteins in corn seeds; bio- proteins with the ultimate aim of estab- chemical genetics of cultured plant lishing

Smallpox and pan-Orthodox Virus Detection by Real-Time 3’-Minor Groove Binder TaqMan Assays Oil the Roche LightCycler and the Cepheid Smart Cycler Platforms

DTIC Science & Technology

2003-11-08

Bacillus anthracis BA0068 Ames Sterne SPS 97.13.213 Bacillus cereus Bacillus coagulans Bacillus licheniformis Bacillus macerans Bacillus ...megaterium Bacillus polymyxa Bacillus sphaericus Bacillus stearothermophilus Bacillus subtilis subsp. niger Bacillus thuringiensis Bacillus popilliae...varicella- zoster virus, and Bacillus anthracis DNA by LightCycler polymerase chain reaction after autoclaving:

Evaluation of the LightCycler Staphylococcus MGRADE Kits on Positive Blood Cultures That Contained Gram-Positive Cocci in Clusters

PubMed Central

Shrestha, Nabin K.; Tuohy, Marion J.; Padmanabhan, Ravindran A.; Hall, Gerri S.; Procop, Gary W.

2005-01-01

We evaluated the Roche LightCycler Staphylococcus MGRADE kits to differentiate between Staphylococcus aureus and coagulase-negative staphylococci in blood cultures growing clusters of gram-positive cocci. Testing 100 bottles (36 containing S. aureus), the assay was 100% sensitive and 98.44% specific for S. aureus and 100% sensitive and specific for coagulase-negative staphylococci. PMID:16333115

Evaluation of the LightCycler Staphylococcus M GRADE kits on positive blood cultures that contained gram-positive cocci in clusters.

PubMed

Shrestha, Nabin K; Tuohy, Marion J; Padmanabhan, Ravindran A; Hall, Gerri S; Procop, Gary W

2005-12-01

We evaluated the Roche LightCycler Staphylococcus M(GRADE) kits to differentiate between Staphylococcus aureus and coagulase-negative staphylococci in blood cultures growing clusters of gram-positive cocci. Testing 100 bottles (36 containing S. aureus), the assay was 100% sensitive and 98.44% specific for S. aureus and 100% sensitive and specific for coagulase-negative staphylococci.

EDTA analysis on the Roche MODULAR analyser.

PubMed

Davidson, D F

2007-05-01

Patient specimens can be subject to subtle interference from cross contamination by liquid-based, potassium-containing EDTA anticoagulant, leading to misinterpretation of results. A rapid method for EDTA analysis to detect such contamination is described. An in-house EDTA assay on the Roche MODULAR analyser was assessed for accuracy and precision by comparison with an adjusted calcium difference measurement (atomic absorption and o-cresolphthalein complexone colorimetry). EDTA method versus adjusted calcium difference showed: slope = 1.038 (95% confidence interval [CI] 0.949-1.131); intercept = 0.073 (95% CI 0.018-0.132) mmol/L; r = 0.914; n = 94. However, inter-assay precision of the calcium difference method was estimated to be poorer (coefficient of variation 24.8% versus 3.4% for the automated colorimetric method at an EDTA concentration of 0.25 mmol/L). Unequivocal contamination was observed at an EDTA concentration of > or =0.2 mmol/L. The automated method showed positive interference from haemolysis and negative interference from oxalate. The method was unaffected by lipaemia (triglycerides <20 mmol/L), icterus (bilirubin <500 micromol/L), glucose (<100 mmol/L), iron (<100 micromol/L), and citrate, phosphate or fluoride (all <2.5 mmol/L). The automated colorimetric assay described is an accurate, precise and rapid (3 min) means of detecting EDTA contamination of unhaemolysed biochemistry specimens.

Dissection of the Octoploid Strawberry Genome by Deep Sequencing of the Genomes of Fragaria Species

PubMed Central

Hirakawa, Hideki; Shirasawa, Kenta; Kosugi, Shunichi; Tashiro, Kosuke; Nakayama, Shinobu; Yamada, Manabu; Kohara, Mistuyo; Watanabe, Akiko; Kishida, Yoshie; Fujishiro, Tsunakazu; Tsuruoka, Hisano; Minami, Chiharu; Sasamoto, Shigemi; Kato, Midori; Nanri, Keiko; Komaki, Akiko; Yanagi, Tomohiro; Guoxin, Qin; Maeda, Fumi; Ishikawa, Masami; Kuhara, Satoru; Sato, Shusei; Tabata, Satoshi; Isobe, Sachiko N.

2014-01-01

Cultivated strawberry (Fragaria x ananassa) is octoploid and shows allogamous behaviour. The present study aims at dissecting this octoploid genome through comparison with its wild relatives, F. iinumae, F. nipponica, F. nubicola, and F. orientalis by de novo whole-genome sequencing on an Illumina and Roche 454 platforms. The total length of the assembled Illumina genome sequences obtained was 698 Mb for F. x ananassa, and ∼200 Mb each for the four wild species. Subsequently, a virtual reference genome termed FANhybrid_r1.2 was constructed by integrating the sequences of the four homoeologous subgenomes of F. x ananassa, from which heterozygous regions in the Roche 454 and Illumina genome sequences were eliminated. The total length of FANhybrid_r1.2 thus created was 173.2 Mb with the N50 length of 5137 bp. The Illumina-assembled genome sequences of F. x ananassa and the four wild species were then mapped onto the reference genome, along with the previously published F. vesca genome sequence to establish the subgenomic structure of F. x ananassa. The strategy adopted in this study has turned out to be successful in dissecting the genome of octoploid F. x ananassa and appears promising when applied to the analysis of other polyploid plant species. PMID:24282021

Performance of a commercial assay for the diagnosis of influenza A (H1N1) infection in comparison to the Centers for Disease Control and Prevention protocol of real time RT-PCR.

PubMed

Barbás, María G; Gallego, Sandra V; Castro, Gonzalo M; Baumeister, Elsa; Kademian, Silvia; De Leon, Juan; Cudolá, Analía

2012-01-01

At the time of influenza A (H1N1) emergency, the WHO responded with remarkable speed by releasing guidelines and a protocol for a real-time RT-PCR assay (rRT-PCR). The aim of the present study was to evalúate the performance of the "Real Time Ready Influenza A/H1N1 Detection Set" (June 2009)-Roche kit in comparison to the CDC reference rRT-PCR protocol. The overall sensitivity of the Roche assay for detection of the Inf A gene in the presence or absence of the H1 gene was 74.5 %. The sensitivity for detecting samples that were only positive for the Inf A gene (absence of the H1 gene) was 53.3 % whereas the sensitivity for H1N1-positive samples (presence of the Inf A gene and any other swine gene) was 76.4 %. The specificity of the assay was 97.1 %. A new version of the kit (November 2009) is now available, and a recent evaluation of its performance showed good sensitivity to detect pandemic H1N1 compared to other molecular assays.

Robe's Restricted Problem of 2 + 2 Bodies with a Roche Ellipsoid - Triaxial System

NASA Astrophysics Data System (ADS)

Aggarwal, Rajiv; Kaur, Bhavneet; Yadav, Sushil

2018-03-01

This paper investigates the motion of two infinitesimal masses on the location and stability of the equilibrium points in Robe's restricted problem of 2 + 2 bodies with the bigger primary a Roche ellipsoid and the smaller a triaxial body. We suppose the bigger primary of mass m 1 to be filled with a homogeneous incompressible fluid of density ρ 1. The third and the fourth bodies (of mass m 3 and m 4 respectively) are small solid spheres of density ρ 3 and ρ 4 respectively inside the ellipsoid, with the assumption that the mass and the radius of the third and the fourth body are infinitesimal. We assume that m 2 is describing a circle around m 1. The masses m 3 and m 4 mutually attract each other, do not influence the motion of m 1 and m 2 but are influenced by them. We have taken into consideration all the three components of the pressure field in deriving the expression for the buoyancy force viz (i) due to the own gravitational field of the fluid (ii) that originating in the attraction of m 2 (iii) that arising from the centrifugal force. In this paper, equilibrium solutions of m 3 and m 4 and their linear stability are analyzed.

Numerical Simulations of Dynamical Mass Transfer in Binaries

NASA Astrophysics Data System (ADS)

Motl, P. M.; Frank, J.; Tohline, J. E.

1999-05-01

We will present results from our ongoing research project to simulate dynamically unstable mass transfer in near contact binaries with mass ratios different from one. We employ a fully three-dimensional self-consistent field technique to generate synchronously rotating polytropic binaries. With our self-consistent field code we can create equilibrium binaries where one component is, by radius, within about 99 of filling its Roche lobe for example. These initial configurations are evolved using a three-dimensional, Eulerian hydrodynamics code. We make no assumptions about the symmetry of the subsequent flow and the entire binary system is evolved self-consistently under the influence of its own gravitational potential. For a given mass ratio and polytropic index for the binary components, mass transfer via Roche lobe overflow can be predicted to be stable or unstable through simple theoretical arguments. The validity of the approximations made in the stability calculations are tested against our numerical simulations. We acknowledge support from the U.S. National Science Foundation through grants AST-9720771, AST-9528424, and DGE-9355007. This research has been supported, in part, by grants of high-performance computing time on NPACI facilities at the San Diego Supercomputer Center, the Texas Advanced Computing Center and through the PET program of the NAVOCEANO DoD Major Shared Resource Center in Stennis, MS.

The Crowded Magnetosphere Of The Post-Common-Envelope Binary QS Virginis

NASA Astrophysics Data System (ADS)

Hill, Colin

2016-06-01

We present high-speed photometry and high-resolution spectroscopy of the short-period (Prot = 3.6 h) eclipsing post-common-envelope binary QS Virginis (QS Vir). Our UVES spectra span in excess of 6 orbits, over more than a year, and reveal the presence of several large prominences passing in front of both the M star and its white dwarf (WD) companion. Despite showing small variations on a time-scale of days, they persist for more than a year and may last decades. Roche tomography reveals a heavily spotted M star, with long-lived spots remaining in fixed locations, preferentially found on the hemisphere facing the WD. We find the 14,220 ± 350 K WD is relatively massive at 0.782 ± 0.013 M(_{odot}),with a radius of0.01068 ± 0.00007 R(_{odot}), consistent with evolutionary models. The tidally distorted M star has a mass of 0.382 ± 0.006 M(_{odot})and a radius of0.381 ± 0.003 R(_{odot}), also consistent with evolutionary models. Since the M star's radius is still within its Roche lobe and there is no evidence that it is overinflated, we conclude that QS Vir is most likely a pre-cataclysmic binary just about to become semidetached.

COUPLED EVOLUTIONS OF THE STELLAR OBLIQUITY, ORBITAL DISTANCE, AND PLANET'S RADIUS DUE TO THE OHMIC DISSIPATION INDUCED IN A DIAMAGNETIC HOT JUPITER AROUND A MAGNETIC T TAURI STAR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, Yu-Ling; Gu, Pin-Gao; Bodenheimer, Peter H.

We revisit the calculation of the ohmic dissipation in a hot Jupiter presented by Laine et al. by considering more realistic interior structures, stellar obliquity, and the resulting orbital evolution. In this simplified approach, the young hot Jupiter of one Jupiter mass is modeled as a diamagnetic sphere with a finite resistivity, orbiting across tilted stellar magnetic dipole fields in vacuum. Since the induced ohmic dissipation occurs mostly near the planet's surface, we find that the dissipation is unable to significantly expand the young hot Jupiter. Nevertheless, the planet inside a small corotation orbital radius can undergo orbital decay bymore » the dissipation torque and finally overfill its Roche lobe during the T Tauri star phase. The stellar obliquity can evolve significantly if the magnetic dipole is parallel/antiparallel to the stellar spin. Our results are validated by the general torque-dissipation relation in the presence of the stellar obliquity. We also run the fiducial model of Laine et al. and find that the planet's radius is sustained at a nearly constant value by the ohmic heating, rather than being thermally expanded to the Roche radius as suggested by the authors.« less

The Influence of Coronal Mass Ejections on the Mass-loss Rates of Hot-Jupiters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cherenkov, A.; Bisikalo, D.; Fossati, L.

Hot-Jupiters are subject to extreme radiation and plasma flows coming from their host stars. Past ultraviolet Hubble Space Telescope observations, supported by hydrodynamic models, confirmed that these factors lead to the formation of an extended envelope, part of which lies beyond the Roche lobe. We use gas-dynamic simulations to study the impact of time variations in the parameters of the stellar wind, namely that of coronal mass ejections (CMEs), on the envelope of the typical hot-Jupiter HD 209458b. We consider three CMEs characterized by different velocities and densities, taking their parameters from typical CMEs observed for the Sun. The perturbationsmore » in the ram-pressure of the stellar wind during the passage of each CME tear off most of the envelope that is located beyond the Roche lobe. This leads to a substantial increase of the mass-loss rates during the interaction with the CME. We find that the mass lost by the planet during the whole crossing of a CME is of ≈10{sup 15} g, regardless of the CME taken into consideration. We also find that over the course of 1 Gyr, the mass lost by the planet because of CME impacts is comparable to that lost because of high-energy stellar irradiation.« less

Extremely high myoglobin plasma concentrations producing hook effect in a critically ill patient.

PubMed

Kurt-Mangold, Michelle; Drees, Denny; Krasowski, Matthew D

2012-12-24

A 21-year old female suffered a cardiac arrest after a one week history of viral illness later shown to be caused by influenza B. The patient required extended cardiopulmonary resuscitation and had further complications including compartment syndrome. Plasma myoglobin concentration was measured using the Roche Diagnostics electrochemiluminescent myoglobin assay. The myoglobin concentration was 205,590 μg/l in an undiluted specimen, consistent with severe rhabdomyolysis. Subsequent myoglobin concentrations measured two days later showed dramatic decreases to approximately 1000 μg/l, raising suspicion of a hook effect. Dilution and re-analysis of the specimens revealed that the actual myoglobin concentrations were >395,000 μg/l, with one specimen possessing an estimated myoglobin concentration of >600,000 μg/l. Interestingly, three specimens from this patient did not show evidence of hook effect, with undiluted specimens producing myoglobin concentrations as high as 284,000 μg/l. Retrospective analysis of myoglobin results over an 8-year period did not reveal other cases with suspicion of hook effect. The case patient had the highest myoglobin concentrations out of 7301 specimens. This case illustrates that while the Roche myoglobin assay has a very wide dynamic range, hook effect can occur with extremely high concentrations of plasma myoglobin. Copyright © 2012 Elsevier B.V. All rights reserved.

Profile of Roche's Ariosa Harmony prenatal test.

PubMed

Bevilacqua, Elisa; Resta, Serena; Carlin, Andrew; Kang, Xin; Cos Sanchez, Teresa; de Marchin, Jérôme; Jani, Jacques C

2018-06-18

Roche's Ariosa Harmony TM Prenatal Test, a noninvasive cfDNA (cell-free DNA) method for major trisomies has been available since January-2013 at the authors unit and tests were sent to California. From July-2017 onwards, prenatal cfDNA has been reimbursed in Belgium for all pregnancies, however since then samples are sent to a local technology transfer center. Little data are available on patient's profile and choices towards cfDNA and on the performance of local technology transfer centers. Areas covered: The profiles and choices of women regarding this test were evaluated. Further, the performance of cfDNA at the local center was compared to the one in California. The results showed that women from the Netherlands, as compared to Belgium, were more likely to undergo cfDNA testing for maternal request and would be less likely to undergo karyotyping if cfDNA were unavailable, and therefore are better candidates for cfDNA testing, when this is used as first-line screening. The local test failure rate was nearly twice that of the main laboratory in California, however when repeated, the success rate was quite high. Expert commentary: The findings highlight the importance of conducting these types of studies, before decisions about clinical implementation are made by national governments and ministries of health.

NG6: Integrated next generation sequencing storage and processing environment.

PubMed

Mariette, Jérôme; Escudié, Frédéric; Allias, Nicolas; Salin, Gérald; Noirot, Céline; Thomas, Sylvain; Klopp, Christophe

2012-09-09

Next generation sequencing platforms are now well implanted in sequencing centres and some laboratories. Upcoming smaller scale machines such as the 454 junior from Roche or the MiSeq from Illumina will increase the number of laboratories hosting a sequencer. In such a context, it is important to provide these teams with an easily manageable environment to store and process the produced reads. We describe a user-friendly information system able to manage large sets of sequencing data. It includes, on one hand, a workflow environment already containing pipelines adapted to different input formats (sff, fasta, fastq and qseq), different sequencers (Roche 454, Illumina HiSeq) and various analyses (quality control, assembly, alignment, diversity studies,…) and, on the other hand, a secured web site giving access to the results. The connected user will be able to download raw and processed data and browse through the analysis result statistics. The provided workflows can easily be modified or extended and new ones can be added. Ergatis is used as a workflow building, running and monitoring system. The analyses can be run locally or in a cluster environment using Sun Grid Engine. NG6 is a complete information system designed to answer the needs of a sequencing platform. It provides a user-friendly interface to process, store and download high-throughput sequencing data.

Potential mapping with charged-particle beams

NASA Technical Reports Server (NTRS)

Robinson, J. W.; Tillery, D. G.

1979-01-01

Experimental methods of mapping the equipotential surfaces near some structure of interest rely on the detection of charged particles which have traversed the regions of interest and are detected remotely. One method is the measurement of ion energies for ions created at a point of interest and expelled from the region by the fields. The ion energy at the detector in eV corresponds to the potential where the ion was created. An ionizing beam forms the ions from background neutrals. The other method is to inject charged particles into the region of interest and to locate their exit points. A set of several trajectories becomes a data base for a systematic mapping technique. An iterative solution of a boundary value problem establishes concepts and limitations pertaining to the mapping problem.

Modeling of a carbon nanotube ultracapacitor.

PubMed

Orphanou, Antonis; Yamada, Toshishige; Yang, Cary Y

2012-03-09

The modeling of carbon nanotube ultracapacitor (CNU) performance based on the simulation of electrolyte ion motion between the cathode and the anode is described. Using a molecular dynamics (MD) approach, the equilibrium positions of the electrode charges interacting through the Coulomb potential are determined, which in turn yield the equipotential surface and electric field associated with the capacitor. With an applied ac voltage, the current is computed based on the nanotube and electrolyte particle distribution and interaction, resulting in the frequency-dependent impedance Z(ω). From the current and impedance profiles, the Nyquist and cyclic voltammetry (CV) plots are then extracted. The results of these calculations compare well with existing experimental data. A lumped-element equivalent circuit for the CNU is proposed and the impedance computed from this circuit correlates well with the simulated and measured impedances.

Charge interaction between particle-laden fluid interfaces.

PubMed

Xu, Hui; Kirkwood, John; Lask, Mauricio; Fuller, Gerald

2010-03-02

Experiments are described where two oil/water interfaces laden with charged particles move at close proximity relative to one another. The particles on one of the interfaces were observed to be attracted toward the point of closest approach, forming a denser particle monolayer, while the particles on the opposite interface were repelled away from this point, forming a particle depletion zone. Such particle attraction/repulsion was observed even if one of the interfaces was free of particles. This phenomenon can be explained by the electrostatic interaction between the two interfaces, which causes surface charges (charged particles and ions) to redistribute in order to satisfy surface electric equipotential at each interface. In a forced particle oscillation experiment, we demonstrated the control of charged particle positions on the interface by manipulating charge interaction between interfaces.

Shape, Density, and Geology of the Nucleus of Comet 103P/Hartley 2

NASA Technical Reports Server (NTRS)

Thomas, P.C.; A'hearn, Michael F.; Veverka, Joseph; Belton, Michael J. S.; Kissel, Jochen; Belton, Michael J. S.; Klaasen, Kenneth P.; McFadden, Lucy A.; Melosh, H. Jay; Schultz, Peter H.;

A study of the electric field in an open magnetospheric model

NASA Technical Reports Server (NTRS)

Stern, D. P.

1973-01-01

Recently, Svalgaard and Heppner reported two separate features of the polar electromagnetic field that correlate with the dawn-dusk component of the interplanetary magnetic field. This work attempts to explain these findings in terms of properties of the open magnetosphere. The topology and qualitative properties of the open magnetosphere are first studied by means of a simple model, consisting of a dipole in a constant field. Many such properties are found to depend on the separation line, a curve connecting neutral points and separating different field line regimes. In the simple model it turns out that the electric field in the central polar cap tends to point from dawn to dusk for a wide variety of external fields, but, near the boundary of the polar cap, electric equipotentials are deformed into crescents.

Flaviviruses

DTIC Science & Technology

1990-01-01

R, Paryanonda A. Human immunoglobulin M anti- virus de lots de moustiques adultes males et femelles. Med body in the serodiagnosis of Japanese...Immun 274. Roche JC, Cordellier R, Hervy JP, et al. Isolement de 96 1984;43:429-43 1. souches de virus dengue 2 a partir de moustiques captures en...dengue chez les moustiques . C R Acad Sci Paris persisting virus. Acta Virol (Praha) 1981 ;25:352-360. 1987;304:347-350. 257. Pool WA, Brownlee A, Wilson

Rapid Identification of Genetic Modifications in Bacillus anthracis Using Whole Genome Draft Sequences Generated by 454 Pyrosequencing

DTIC Science & Technology

2010-08-25

or intentional genetic modifications that circumvent the targets of the detection assays or in the case of a biological attack using an antibiotic ...genetic changes conferring antibiotic resistance can be deciphered rapidly and accurately using WGS. We demonstrate the utility of Roche 454...Rapid Identification of Genetic Modifications in Bacillus anthracis Using Whole Genome Draft Sequences Generated by 454 Pyrosequencing Peter E. Chen1

Novel Inhibitors of Protein-Protein Interaction for Prostate Cancer Therapy

DTIC Science & Technology

2014-04-01

treated mice compared to vehicle control. A subset of mice was followed by longitudinal MRI imaging for prostate tumor growth. As shown in Figure...treated (N=7) mice were followed by longitudinal MRI imaging for tumor growth (bottom panel). 9 KEY RESEARCH ACCOMPLISHMENTS • Identified...EDTA) containing a tablet of complete protease inhibitors from Roche (Indianapolis, IN). Total protein from each sample was separated on a 4–12% Bis

Integrated Control and Assessment of Knapweed and Cheatgrass on Department of Defense Installations. Addendum

DTIC Science & Technology

2008-02-01

United States are infested by exotic plant species, particularly knapweeds (Centaurea maculosa , C. diffusa) (Roché 1994, Hirsch and Leitch 1996, Sheley et...population of spotted knapweed (Centaurea maculosa ) at this site was identified by base personnel as a high priority for control. The area is regularly...2006. Comparative fungal responses in managed spotted knapweed (Centaurea maculosa Lam.), and diffuse knapweed (C. diffusa Lam.) - infested plant

Environmental Assessment for the Construction of a Photovoltaic Solar Array at Laughlin Air Force Base, Texas

DTIC Science & Technology

2011-10-01

Alabama, 1996 Years of Experience: 24 Brian Howard. Ph.D, Quality Assurance Post Doctoral Research Associate, Burnham Institute for Medical... Research , La Jolla, CA, 1991 Post -Doctoral Research Fellow, F. Hoffmann-La Roche & Co., Basel, Switzerland, 1990 Ph.D. Toxicology, Utah State University... research any eligibility determinations, additional archeological testing or avoidance that may be warranted. Thank you for your cooperation in this state

Manipulation of Muscle Glycogen Concentrations Using High and Low Carbohydrate Diets and Exercise

DTIC Science & Technology

1987-08-01

high in carbohydrates in the form of simple sugars (i.e., sucrose, fructose , lactose) and complex carbohydrates (i.e., starches, dietary fiber...AD-A 187 732 REPORT NO T32-87 MANIPULATION OF MUSCLE GLYCOGEN CONCENTRATIONS USING HIGH AND LOW CARBOHYDRATE DIETS AND EXERCISE U S ARMY RESEARCH...Muscle Glycogen Concentrations Using High and Low Carbohydrate Diets and Exercise 12. PERSONAL AUTHOR(S) Buchbinder, J., Pocost, J., Hodgess, L., Roche

Development and Demonstration of a Networked Telepathology 3-D Imaging, Databasing, and Communication System

DTIC Science & Technology

1996-10-01

aligned using an octree search algorithm combined with cross correlation analysis . Successive 4x downsampling with optional and specifiable neighborhood...desired and the search engine embedded in the OODBMS will find the requested imagery and que it to the user for further analysis . This application was...obtained during Hoftmann-LaRoche production pathology imaging performed at UMICH. Versant works well and is easy to use; 3) Pathology Image Analysis

Inferences About the Early Moon From Gravity and Topography

NASA Technical Reports Server (NTRS)

Smith, D. E.; Zuber, M. T.

1998-01-01

Recent spacecraft missions to the Moon have significantly improved our knowledge of the lunar gravity and topography fields, and have raised some new and old questions about the early lunar history. It has frequently been assumed that the shape of the Moon today reflects an earlier equilibrium state and that the Moon has retained some internal strength. Recent analysis indicating a superisostatic state of some lunar basins lends support to this hypothesis. On its simplest level, the present shape of the Moon is slightly flattened by 2.2 +/- 0.2 km while its gravity field, represented by an equipotential surface, is flattened only about 0.5 km. The hydrostatic component to the flattening arising from the Moon's present day rotation contributes only 7 m. This difference between the topographic shape of the MOon and the shape of its gravitational equipotential has frequently been explained as the "memory" of an earlier moon that was rotating faster and had a correspondingly larger hydrostatic flattening. To obtain this amount of hydrostatic flattening from rotation alone, and accounting for the contribution of the present-day gravity field, the Moon's rotation rate would need to be about 15x greater than at present, leading ot a period of < 2 days. Maintaining its synchronous rotation with Earth would require a radius for the Moon's orbit of approximately 9 Earth Radii. Unfortunately, our confidence in the observed lunar flattening is not as great as we would like. The uncertainty of .02 km may not properly reflect the limitations of the Clementine dataset, which did not sample poleward of latitudes 81 N and 79 S. Also, the large variation of topography +/- 8 km seen on the MOon dwarfs our estimate fo the flattening. Further the lunar south pole is on the edge of, or possibly inside the massive deep, South Pole-Aitken Basin. Thus, polar radii could be underestimated. This would yield a smaller flattening, which would imply a greater lunar rotation period and orbital radius. However, Basin compensation states and analyses of support and relaxation of topography at long wavelengths point to a lunar shape that has retained a flattening from an earlier faster rotation period.

An evaluation of krypton propellant in Hall thrusters

NASA Astrophysics Data System (ADS)

Linnell, Jesse Allen

Due to its high specific impulse and low price, krypton has long sparked interest as an alternate Hall thruster propellant. Unfortunately at the moment, krypton's relatively poor performance precludes it as a legitimate option. This thesis presents a detailed investigation into krypton operation in Hall thrusters. These findings suggest that the performance gap can be decreased to 4% and krypton can finally become a realistic propellant option. Although krypton has demonstrated superior specific impulse, the xenon-krypton absolute efficiency gap ranges between 2 and 15%. A phenomenological performance model indicates that the main contributors to the efficiency gap are propellant utilization and beam divergence. Propellant utilization and beam divergence have relative efficiency deficits of 5 and 8%, respectively. A detailed characterization of internal phenomena is conducted to better understand the xenon-krypton efficiency gap. Krypton's large beam divergence is found to be related to a defocusing equipotential structure and a weaker magnetic field topology. Ionization processes are shown to be linked to the Hall current, the magnetic mirror topology, and the perpendicular gradient of the magnetic field. Several thruster design and operational suggestions are made to optimize krypton efficiency. Krypton performance is optimized for discharge voltages above 500 V and flow rates corresponding to an a greater than 0.015 mg/(mm-s), where alpha is a function of flow rate and discharge channel dimensions (alpha = m˙alphab/Ach). Performance can be further improved by increasing channel length or decreasing channel width for a given flow rate. Also, several magnetic field design suggestions are made to enhance ionization and beam focusing. Several findings are presented that improve the understanding of general Hall thruster physics. Excellent agreement is shown between equipotential lines and magnetic field lines. The trim coil is shown to enhance beam focusing, ionization processes, and electron dynamics. Electron mobility and the Hall parameter are studied and compared to different mobility models. Azimuthal electron current is studied using a fluid and particle drift approach. Analyses of several magnetic field features are conducted and simple tools are suggested for the development of future Hall thrusters. These findings have strong implications for future Hall thruster design, lifetimes, and modeling.

The theoretical simulation on electrostatic distribution of 1st proximity region in proximity focusing low-light-level image intensifier

NASA Astrophysics Data System (ADS)

Zhang, Liandong; Bai, Xiaofeng; Song, De; Fu, Shencheng; Li, Ye; Duanmu, Qingduo

2015-03-01

Low-light-level night vision technology is magnifying low light level signal large enough to be seen by naked eye, which uses the photons - photoelectron as information carrier. Until the micro-channel plate was invented, it has been possibility for the realization of high performance and miniaturization of low-light-level night vision device. The device is double-proximity focusing low-light-level image intensifier which places a micro-channel plate close to photocathode and phosphor screen. The advantages of proximity focusing low-light-level night vision are small size, light weight, small power consumption, no distortion, fast response speed, wide dynamic range and so on. It is placed parallel to each other for Micro-channel plate (both sides of it with metal electrode), the photocathode and the phosphor screen are placed parallel to each other. The voltage is applied between photocathode and the input of micro-channel plate when image intensifier works. The emission electron excited by photo on the photocathode move towards to micro-channel plate under the electric field in 1st proximity focusing region, and then it is multiplied through the micro-channel. The movement locus of emission electrons can be calculated and simulated when the distributions of electrostatic field equipotential lines are determined in the 1st proximity focusing region. Furthermore the resolution of image tube can be determined. However the distributions of electrostatic fields and equipotential lines are complex due to a lot of micro-channel existing in the micro channel plate. This paper simulates electrostatic distribution of 1st proximity region in double-proximity focusing low-light-level image intensifier with the finite element simulation analysis software Ansoft maxwell 3D. The electrostatic field distributions of 1st proximity region are compared when the micro-channel plates' pore size, spacing and inclination angle ranged. We believe that the electron beam movement trajectory in 1st proximity region will be better simulated when the electronic electrostatic fields are simulated.

Efectos difusivos en la formación de enanas blancas de Helio de baja masa en sistemas binarios cerrados

NASA Astrophysics Data System (ADS)

De Vito, M. A.; Benvenuto, O. G.

In the last years, and thanks to advances in observational techniques, many astronomers have discovered in a great number of binary radio-pulsars the presence of a helium white dwarf resulting from a previous evolutionary state in which the progenitor of this star experienced one or more episodes of mass transfer to the compact component in the pair. That is the case for PSR B1855+09 (van Kerkwijk, M. H., Bell, J. F, Kaspi, V. M., & Kulkarni, S. R. 2000, ApJ 530, L37), where the mass for the white dwarf is known accurately from measurements of the Shapiro delay of the pulsar signal, MWD = 0.258+0.028-0.016 M⊙; for PSR J02018 + 4232 (Bassa, C. G., van Kerkwijk, M. H., & Kulkarni, S. R. 2003, A&A, 403, 1067), the spectra confirm that the companion is a helium-core white dwarf of ≈ 0.2 M⊙. On the other hand, there are several authors (Ferraro, F., Possenti, A., Sabbi, E., & D'Amico, N. 2003, ApJ, 596, L211; Bassa et al. 2003) that have identified the optical binary companion to the BMSP PSR J1911 - 5958A, located in the halo of the Galactic globular cluster NGC 6752, like a blue star whose position in the color-magnitude diagram is consistent with the cooling sequence of a low-mass, ≈ 0.17 - 0.20 M⊙, low metallicity helium white dwarf at the cluster distance. Finally, the color and magnitude of the stellar companion for B 1620-26 indicate that is a white dwarf of 0.34 ± 0.04 M⊙ (Sigurdson, S., Richer, H. B., Hansen, B. M., Stairs, I. H. & Thorset, S. E. 2003, Science, 301, 193S). This has motivated us to study the formation of low mass helium white dwarfs in the context of binary evolution. For that purpose, using the code of binary evolution, entirely developed in the Facultad de Ciencias Astronómicas y Geofísicas of the Universidad Nacional de La Plata, Argentina, we have investigated the effects of diffusive processes on the evolution of a star member of a close binary system. A similar study was performed for Althaus, L. G., Serenelli, A. M., & Benvenuto, O. G. (2001, MNRAS, 323, 471) but in that paper the mass transfer was mimicked by subtracting mass to a progenitor of 1 M⊙ to obtain the mass for the desired object. Actually, our binary code has a full nuclear reactions network for hydrogen and helium burning that allowed us to follow the abundances of fifteen isotopes throughout the entire evolution of the star. We have also included a detailed equation of state. The mass loss treatment is non conservative. We have modified the conditions for the beginning and end of mass transfer episodes. In our previous version, we assumed it to occur when the stellar radius was greater or smaller, respectively, that the Roche Lobe radius for the star. This introduced numerical problems, especially at the end of mass transfer phases. We adopted H. Ritter (1988, A&A, 202, 93) formulation that considers a finite scale height in the stellar atmosphere. The numerical behaviour in much more satisfactory, besides that it constitutes a more appropriate description for the physical problem. We perform the calculations for the evolution of the primary star in a close binary system of initial mass 2 M⊙, initial period of 1 day, initial mass ratio of 1.4142 and solar metallicity. We have done the calculations in four cases: A) with diffusion and all Roche Lobe overflows, B) with diffusion and only the first Roche Lobe overflow, C) without diffusion and all Roche Lobe overflows, D) without diffusion and only the first Roche Lobe overflow. Cases B) and D) where performed to compare with results obtained for Althaus et al. (2001). The main conclusion of this work is that the age of these objects is mainly determined by diffusive effects, and the late stages of mass transfer, not considered in Althaus et al. (2001), constituted a minor effect on the scales of cooling times.

Modifications and substitutions of the RNA extraction module in the ViroSeq HIV-1 genotyping system version 2: effects on sensitivity and complexity of the assay.

PubMed

Stürmer, Martin; Berger, Annemarie; Doerr, Hans-Wilhelm

2003-12-01

Genotypic testing for HIV-1 resistance to anti-retroviral drugs has become accepted widely as a routine method to guide anti-retroviral therapy. However, implementation into routine high-throughput laboratory diagnosis is difficult due to the complexity of the assay. A commercially available assay is the ViroSeq HIV-1 Genotyping System (Applied Biosystems, Weiterstadt, Germany). We modified and substituted the RNA extraction module to optimize the proportion of samples amplified successfully as follows: 1 ml plasma was concentrated by ultracentrifugation and extracted according to the manufacturer's instructions (Kit), by substituting the lysis buffer (Roche, Roche Diagnostics GmbH, Mannheim, Germany), and by using the QIAamp Viral RNA Kit (Qiagen GmbH, Hilden, Germany) with elution volumes of 60 (Q60) or 50 micro l (Q50). Overall Q50 showed a higher success rate (97%) than the other extraction modules used (range 88-91%). In samples with a viral load range of 1,000-4,999 copies/ml, Q50 was superior (95 vs. 65% to 83%), while in samples with a viral load range of 5,000-9,999 copies/ml or those with 10,000 or more copies/ml, the success rate of the extraction procedures showed no significant differences. In 18 samples, which were negative using the Kit or Roche extraction, Q60 resulted in 7/18 positive results; in addition the Q50 was successful in amplifying 7/10 of the Q60 negative samples. When investigating samples with a measurable viral load of less than 1,000 copies/ml or lower, Q50 had the highest success rate with 80% compared to the other procedures (33-63%). A statistically significant new cut-off could be defined for Q50 at a value of 250 copies/ml. The results showed clearly that the ViroSeq System is suitable for analyzing the HIV-1 genotype over a wide range of viral loads but could be improved significantly when substituting the RNA extraction module with Q50 without using a nested PCR protocol. This is of great importance as it avoids further time- and cost-intensive steps. Copyright 2003 Wiley-Liss, Inc.

Multicenter Comparison of Roche COBAS AMPLICOR MONITOR Version 1.5, Organon Teknika NucliSens QT with Extractor, and Bayer Quantiplex Version 3.0 for Quantification of Human Immunodeficiency Virus Type 1 RNA in Plasma

PubMed Central

Murphy, Donald G.; Côté, Louise; Fauvel, Micheline; René, Pierre; Vincelette, Jean

2000-01-01

The performance and characteristics of Roche COBAS AMPLICOR HIV-1 MONITOR version 1.5 (CA MONITOR 1.5) UltraSensitive (usCA MONITOR 1.5) and Standard (stCA MONITOR 1.5) procedures, Organon Teknika NucliSens HIV-1 RNA QT with Extractor (NucliSens), and Bayer Quantiplex HIV RNA version 3.0 (bDNA 3.0) were compared in a multicenter trial. Samples used in this study included 460 plasma specimens from human immunodeficiency virus (HIV) type 1 (HIV-1)-infected persons, 100 plasma specimens from HIV antibody (anti-HIV)-negative persons, and culture supernatants of HIV-1 subtype A to E isolates diluted in anti-HIV-negative plasma. Overall, bDNA 3.0 showed the least variation in RNA measures upon repeat testing. For the Roche assays, usCA MONITOR 1.5 displayed less variation in RNA measures than stCA MONITOR 1.5. NucliSens, at an input volume of 2 ml, showed the best sensitivity. Deming regression analysis indicated that the results of all three assays were significantly correlated (P < 0.0001). However, the mean difference in values between CA MONITOR 1.5 and bDNA 3.0 (0.274 log10 RNA copies/ml; 95% confidence interval, 0.192 to 0.356) was significantly different from 0, indicating that CA MONITOR 1.5 values were regularly higher than bDNA 3.0 values. Upon testing of 100 anti-HIV-negative plasma specimens, usCA MONITOR 1.5 and NucliSens displayed 100% specificity, while bDNA 3.0 showed 98% specificity. NucliSens quantified 2 of 10 non-subtype B viral isolates at 1 log10 lower than both CA MONITOR 1.5 and bDNA 3.0. For NucliSens, testing of specimens with greater than 1,000 RNA copies/ml at input volumes of 0.1, 0.2, and 2.0 ml did not affect the quality of results. Additional factors differing between assays included specimen throughput and volume requirements, limit of detection, ease of execution, instrument work space, and costs of disposal. These characteristics, along with assay performance, should be considered when one is selecting a viral load assay. PMID:11060065

A proposal for adopting a standard coordinate system for defining atmospheric nomenclature for the giant planets

NASA Technical Reports Server (NTRS)

Beebe, R.

1986-01-01

Although the albedo of specific belts and zones varies as a function of time, there is evidence that wind maxima may be fixed in latitude. Before considering a standard notation for wind jets, it is necessary to establish a coordinate system within which the nomenclature would be defined. Traditionally, the BAA has used planetographic latitudes; however, this system is based not only on an accurate determination of the polar diameter but also on the assumption that the equipotential surfaces can be represented by biaxial ellipsoids. The International Astronomical Union strives to adopt unambiguous nomenclature that will be universally acceptable. It is proposed that planetocentric coordinates be utilized and that a standardized value of the ratio of the polar diameter to the equatorial diameter be established for each planet to facilitate transformation into planetographic coordinates.

Particle flows to shape and voltage surface discontinuities in the electron sheath surrounding a high voltage solar array in LEO

NASA Technical Reports Server (NTRS)

Metz, Roger N.

1991-01-01

This paper discusses the numerical modeling of electron flows from the sheath surrounding high positively biased objects in LEO (Low Earth Orbit) to regions of voltage or shape discontinuity on the biased surfaces. The sheath equations are derived from the Two-fluid, Warm Plasma Model. An equipotential corner and a plane containing strips of alternating voltage bias are treated in two dimensions. A self-consistent field solution of the sheath equations is outlined and is pursued through one cycle. The electron density field is determined by numerical solution of Poisson's equation for the electrostatic potential in the sheath using the NASCAP-LEO relation between electrostatic potential and charge density. Electron flows are calculated numerically from the electron continuity equation. Magnetic field effects are not treated.

PIC code modeling of spacecraft charging potential during electron beam injection into a background of neutral gas and plasma, part 1

NASA Technical Reports Server (NTRS)

Koga, J. K.; Lin, C. S.; Winglee, R. M.

1989-01-01

Injections of nonrelativistic electron beams from an isolated equipotential conductor into a uniform background of plasma and neutral gas were simulated using a 2-D electrostatic particle code. The ionization effects on spacecraft charging are examined by including interactions of electrons with neutral gas. The simulations show that the conductor charging potential decreases with increasing neutral background density due to the production of secondary electrons near the conductor surface. In the spacecraft wake, the background electrons accelerated towards the charged spacecraft produce an enhancement of secondary electrons and ions. Simulations run for longer times indicate that the spacecraft potential is further reduced and short wavelength beam-plasma oscillations appear. The results are applied to explain the spacecraft charging potential measured during the SEPAC experiments from Spacelab 1.

Corrected body surface potential mapping.

PubMed

Krenzke, Gerhard; Kindt, Carsten; Hetzer, Roland

2007-02-01

In the method for body surface potential mapping described here, the influence of thorax shape on measured ECG values is corrected. The distances of the ECG electrodes from the electrical heart midpoint are determined using a special device for ECG recording. These distances are used to correct the ECG values as if they had been measured on the surface of a sphere with a radius of 10 cm with its midpoint localized at the electrical heart midpoint. The equipotential lines of the electrical heart field are represented on the virtual surface of such a sphere. It is demonstrated that the character of a dipole field is better represented if the influence of the thorax shape is reduced. The site of the virtual reference electrode is also important for the dipole character of the representation of the electrical heart field.

Current distribution in a three-dimensional IC analyzed by a perturbation method. Part 1: A simple steady state theory

NASA Technical Reports Server (NTRS)

Edmonds, Larry D.

1987-01-01

The steady state current distribution in a three dimensional integrated circuit is presented. A device physics approach, based on a perturbation method rather than an equivalent lumped circuit approach, is used. The perturbation method allows the various currents to be expressed in terms of elementary solutions which are solutions to very simple boundary value problems. A Simple Steady State Theory is the subtitle because the most obvious limitation of the present version of the analysis is that all depletion region boundary surfaces are treated as equipotential surfaces. This may be an adequate approximation in some applications but it is an obvious weakness in the theory when applied to latched states. Examples that illustrate the use of these analytical methods are not given because they will be presented in detail in the future.

Samples of Asteroid Surface Ponded Deposits in Chondritic Meteorites

NASA Technical Reports Server (NTRS)

Zolensky, M. E.; Lee, R.; Le, L.

2004-01-01

One of the many unexpected observations of asteroid 433 Eros by the Near Earth Asteroid Rendezvous (NEAR) mission was the many ponds of fine-grained materials [1-3]. The ponds have smooth surfaces, and define equipotential surfaces up to 10's of meters in diameter [4]. The ponds have a uniformly sub-cm grain size and appear to be cohesive or indurated to some degree, as revealed by slumping. The ponds appear to be concentrated within 30 degrees of the equator of Eros, where gravity is lowest. There is some insight into the mineralogy and composition of the ponds surfaces from NEAR spectroscopy [2,4,5,6]. Compared to the bulk asteroid, ponds: (1) are distinctly bluer (high 550/760 nm ratio), (2) have a deeper 1um mafic band, (3) have reflectance elevated by 5%.

Parallel electric fields detected via conjugate electron echoes during the Echo 7 sounding rocket flight

NASA Technical Reports Server (NTRS)

Nemzek, R. J.; Winckler, J. R.

1991-01-01

Electron detectors on the Echo 7 active sounding rocket experiment measured 'conjugate echoes' resulting from artificial electron beam injections. Analysis of the drift motion of the electrons after a complete bounce leads to measurements of the magnetospheric convection electric field mapped to ionospheric altitudes. The magnetospheric field was highly variable, changing by tens of mV/m on time scales of as little as hundreds of millisec. While the smallest-scale magnetospheric field irregularities were mapped out by ionospheric conductivity, larger-scale features were enhanced by up to 50 mV/m in the ionosphere. The mismatch between magnetospheric and ionspheric convection fields indicates a violation of the equipotential field line condition. The parallel fields occurred in regions roughly 10 km across and probably supported a total potential drop of 10-100 V.

A monopole model for annihilation line emission from the Galactic center

NASA Astrophysics Data System (ADS)

Wang, D. Y.; Peng, Q. H.

Two traditional theoretical interpretations of the observed plasmapause are compared, namely, the plasmapause as: (1) the boundary between closed flux tubes that have been in the inner magnetosphere for several days and those that have recently drifted in from the magnetotail or (2) the last closed electric equipotential. Although the two interpretations become equivalent in the case where the electric-field pattern is steady for several days, interpretation 1 seems theoretically more secure for typical magnetospheric conditions. The results of old theoretical studies of the effects of time variations in the electric-field pattern on the shape of the plasmapause are reviewed briefly. The formulation of the present version of the Rice Convection Model is also reviewed. Preliminary results of recent computations of quiet-time electric fields, carried out with this model, are presented and discussed.

The Ascent of Olympus - An Everest Anniversary Perspective

NASA Astrophysics Data System (ADS)

Cockell, C. S.

Olympus Mons, at 21,183 m above the Mars gravitational equipotential, stands just under 2.5 times the height of Mount Everest. Symbolically, as the highest construct in the Solar System, it is the most important feature to be climbed. Despite its powerful symbolism, the mountain presents one of the most tedious long distance expeditions on Mars - a ~300 km journey up a near constant 5 degree slope. Only at the beginning and the end of the expedition do the scarp and caldera cliffs present impressive climbs. In almost all respects Olympus presents environmental challenges much worse than Everest, apart from the lack of fatal storms, perhaps the only environmental factor in which Olympus is an improvement. Similarly to Everest, Olympus presents scien- tific questions of immense interest. In this mini-review I compare Olympus and Everest as exploratory and scientific challenges.

WOLF: a computer code package for the calculation of ion beam trajectories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vogel, D.L.

1985-10-01

The WOLF code solves POISSON'S equation within a user-defined problem boundary of arbitrary shape. The code is compatible with ANSI FORTRAN and uses a two-dimensional Cartesian coordinate geometry represented on a triangular lattice. The vacuum electric fields and equipotential lines are calculated for the input problem. The use may then introduce a series of emitters from which particles of different charge-to-mass ratios and initial energies can originate. These non-relativistic particles will then be traced by WOLF through the user-defined region. Effects of ion and electron space charge are included in the calculation. A subprogram PISA forms part of this codemore » and enables optimization of various aspects of the problem. The WOLF package also allows detailed graphics analysis of the computed results to be performed.« less

Evaluation of the Cobas TaqMan MTB test for the detection of Mycobacterium tuberculosis complex according to acid-fast-bacillus smear grades in respiratory specimens.

PubMed

Huh, Hee Jae; Koh, Won-Jung; Song, Dong Joon; Ki, Chang-Seok; Lee, Nam Yong

2015-02-01

We evaluated the performance of the Cobas TaqMan MTB test (Roche Diagnostics, Basel, Switzerland), stratified by acid-fast bacilli (AFB) smear grades. The sensitivity of this test in smear-positive specimens was >95% in all grades, while that in trace and negative specimens was 85.3% and 34.4%, respectively. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

1998 UBV Light Curves of Eclipsing Binary AI Draconis and Absolute Parameters

NASA Astrophysics Data System (ADS)

Jassur, D. M. Z.; Khaledian, M. S.; Kermani, M. H.

New UBV photometry of Algol-Type eclipsing binary star AI Dra and the absolute physical parameters of this system have been presented. The light curve analysis carried out by the method of differential corrections indicates that both components are inside their Roche-Lobes. From combining the photometric solution with spectroscopic data obtained from velocity curve analysis, it has been found that the system consist of a main sequence primary and an evolved (subgiant) secondary.

Mechanisms Down-Regulating Sprouty1, a Growth Inhibitor in Prostate Cancer

DTIC Science & Technology

2007-10-01

Development 1999, 126: 4139-4147. 6. de Maximy AA, Nakatake Y, Moncada S, Itoh N, Thiery JP, Bellusci S: Cloning and expression pattern of a mouse...J Biol Chem 2004, 279: 22992-22995. 10. Gross I, Bassit B, Benezra M, Licht JD: Mammalian sprouty proteins inhibit cell growth and differentiation...Unincorporated [γ-32P] dATP were removed by purifying the probes using a G-25 ( Fine ) Sephadex Quick spin columns (Roche). The EMSAs were carried

A Field-expedient Method for Detection of Leptospirosis Causative Agents in Rodents

DTIC Science & Technology

2012-01-01

carboxytetramethylrhodamine (TAMRA)) (Roche Molecular Diagnostics, Pleasanton, California).24,25 Polymerase Chain Reaction. Wet reagent LPS PCR assay...City, Utah). Primers and probe were optimized with R.A.P.I.D. wet reagents and the optimum condition was 5 mmol/L MgCl2, 400 nmol/L primers, 100 nmol...for 20 seconds of combined annealing and primer extension. Linearity and Limit of Detection. The linearity of the LPS freeze-dried assay was

Cognitive Load in Mild Traumatic Brain Injury: A Pupillometric Assessment of Multiple Attentional Processes

DTIC Science & Technology

2016-05-20

such as Schizophrenia and ADHD (27; 77). Another such condition is mild traumatic brain injury. Mild TBI is caused by a closed head injury (e.g., car...cognitive load on semantic priming in patients with schizophrenia . Journal of Abnormal Psychology 104:576 26. Hogan MJ, Carolan L, Roche RAP...performance and cerebral functional response during working memory in schizophrenia . Schizophrenia research 53:45-56 28. Iverson G, Lange R. 2011

Sesquinary Catenae on the Martian Satellite Phobos from Reaccretion of Escaping Ejecta

DTIC Science & Technology

2016-08-30

Life near the Roche limit—behavior of ejecta from satellites close to planets . Icarus 42, 422–441 (1980). 13. Soter, S. in Studies of the Terrestrial...sesquinaries are probes of the primary ejection process, but are also bound to the dynamics of the planet -satellite system. Unlike secondaries, to...intermediate between vesc and the orbital velocity vorb. When the satellite is far from the planet , sesquinaries can produce primary- like crater morphology

Evolutionary Processes in Multiple Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eggleton, P P; Kisseleva-Eggleton, L

There are several ways in which triple stars can evolve in somewhat unusual ways. They discuss two situations where Case A Roche-lobe overflow, followed by a merger, can produce anomalous wide binaries such as {gamma} Per; and Kozai cycles in triples with non-parallel orbits, which can produce merged rapidly-rotating stars like AB Dor, and which can also lead to the delayed ejection of one component of a multiple, as may have been observed in T Tau in 1998.

Performance evaluation of new automated hepatitis B viral markers in the clinical laboratory: two quantitative hepatitis B surface antigen assays and an HBV core-related antigen assay.

PubMed

Park, Yongjung; Hong, Duck Jin; Shin, Saeam; Cho, Yonggeun; Kim, Hyon-Suk

2012-05-01

We evaluated quantitative hepatitis B surface antigen (qHBsAg) assays and a hepatitis B virus (HBV) core-related antigen (HBcrAg) assay. A total of 529 serum samples from patients with hepatitis B were tested. HBsAg levels were determined by using the Elecsys (Roche Diagnostics, Indianapolis, IN) and Architect (Abbott Laboratories, Abbott Park, IL) qHBsAg assays. HBcrAg was measured by using Lumipulse HBcrAg assay (Fujirebio, Tokyo, Japan). Serum aminotransferases and HBV DNA were respectively quantified by using the Hitachi 7600 analyzer (Hitachi High-Technologies, Tokyo, Japan) and the Cobas AmpliPrep/Cobas TaqMan test (Roche). Precision of the qHBsAg and HBcrAg assays was assessed, and linearity of the qHBsAg assays was verified. All assays showed good precision performance with coefficients of variation between 4.5% and 5.3% except for some levels. Both qHBsAg assays showed linearity from 0.1 to 12,000.0 IU/mL and correlated well (r = 0.9934). HBsAg levels correlated with HBV DNA (r = 0.3373) and with HBcrAg (r = 0.5164), and HBcrAg also correlated with HBV DNA (r = 0.5198; P < .0001). This observation could provide impetus for further research to elucidate the clinical usefulness of the qHBsAg and HBcrAg assays.

Participation costs can suppress the evolution of upstream reciprocity.

PubMed

Peña, Jorge; Pestelacci, Enea; Berchtold, André; Tomassini, Marco

2011-03-21

Indirect reciprocity, one of the many mechanisms proposed to explain the evolution of cooperation, is the idea that altruistic actions can be rewarded by third parties. Upstream or generalized reciprocity is one type of indirect reciprocity in which individuals help someone if they have been helped by somebody else in the past. Although empirically found to be at work in humans, the evolution of upstream reciprocity is difficult to explain from a theoretical point of view. A recent model of upstream reciprocity, first proposed by Nowak and Roch (2007) and further analyzed by Iwagami and Masuda (2010), shows that while upstream reciprocity alone does not lead to the evolution of cooperation, it can act in tandem with mechanisms such as network reciprocity and increase the total level of cooperativity in the population. We argue, however, that Nowak and Roch's model systematically leads to non-uniform interaction rates, where more cooperative individuals take part in more games than less cooperative ones. As a result, the critical benefit-to-cost ratios derived under this model in previous studies are not invariant with respect to the addition of participation costs. We show that accounting for these costs can hinder and even suppress the evolution of upstream reciprocity, both for populations with non-random encounters and graph-structured populations. Copyright © 2011 Elsevier Ltd. All rights reserved.

In Vitro Metabolism of 20(R)-25-Methoxyl-Dammarane-3, 12, 20-Triol from Panax notoginseng in Human, Monkey, Dog, Rat, and Mouse Liver Microsomes

PubMed Central

Li, Wei; Liu, Li; Sun, Baoshan; Guo, Zhenghong; Shi, Caihong; Zhao, Yuqing

2014-01-01

The present study characterized in vitro metabolites of 20(R)-25-methoxyl-dammarane-3β, 12β, 20-triol (20(R)-25-OCH3-PPD) in mouse, rat, dog, monkey and human liver microsomes. 20(R)-25-OCH3-PPD was incubated with liver microsomes in the presence of NADPH. The reaction mixtures and the metabolites were identified on the basis of their mass profiles using LC-Q/TOF and were quantified using triple quadrupole instrument by multiple reaction monitoring. A total of 7 metabolites (M1–M7) of the phase I metabolites were detected in all species. 25(R)-OCH3-PPD was metabolized by hydroxylation, dehydrogenation, and O-demethylation. Enzyme kinetic of 20(R)-25-OCH3-PPD metabolism was evaluated in rat and human hepatic microsomes. Incubations studies with selective chemical inhibitors demonstrated that the metabolism of 20(R)-25-OCH3-PPD was primarily mediated by CYP3A4. We conclude that 20(R)-25-OCH3-PPD was metabolized extensively in mammalian species of mouse, rat, dog, monkey, and human. CYP3A4-catalyzed oxygenation metabolism played an important role in the disposition of 25(R)-OCH3-PPD, especially at the C-20 hydroxyl group. PMID:24736630

LUT Reveals a New Mass-transferring Semi-detached Binary

NASA Astrophysics Data System (ADS)

Qian, S.-B.; Zhou, X.; Zhu, L.-Y.; Zejda, M.; Soonthornthum, B.; Zhao, E.-G.; Zhang, J.; Zhang, B.; Liao, W.-P.

2015-12-01

GQ Dra is a short-period eclipsing binary in a double stellar system that was discovered by Hipparcos. Complete light curves in the UV band were obtained with the Lunar-based Ultraviolet Telescope in 2014 November and December. Photometric solutions are determined using the W-D (Wilson and Devinney) method. It is discovered that GQ Dra is a classical Algol-type semi-detached binary where the secondary component is filling the critical Roche lobe. An analysis of all available times of minimum light suggests that the orbital period is increasing continuously at a rate of \\dot{P}=+3.48(+/- 0.23)× {10}-7 days yr-1. This could be explained by mass transfer from the secondary to the primary, which is in agreement with the semi-detached configuration with a lobe-filling secondary. By assuming a conservation of mass and angular momentum, the mass transfer rate is estimated as \\dot{m}=9.57(+/- 0.63)× {10}-8 {M}⊙ {{yr}}-1. All of these results reveal that GQ Dra is a mass-transferring semi-detached binary in a double system that was formed from an initially detached binary star. After the massive primary evolves to fill the critical Roche lobe, the mass transfer will be reversed and the binary will evolve into a contact configuration with two sub-giant or giant component stars.

Comparison of the Abbott Architect i2000 assay, the Roche Modular Analytics E170 assay, and an immunoradiometric assay for serum hepatitis B virus markers.

PubMed

Kim, Hyunjung; Oh, Eun-Jee; Kang, Mi-Sook; Kim, Sung Hoon; Park, Yeon-Joon

2007-01-01

Serum hepatitis B virus (HBV) markers are the most important data for epidemiological screening and clinical diagnosis of HBV infection, especially in endemic areas. We compared the results of the Roche Modular Analytics E170 assay, the Abbott Architect i2000 assay, and an immunoradiometric assay (IRMA) for HBV surface antigen (HBsAg), anti-HBV surface antigen (anti-HBs), HBV e antigen (HBeAg), and anti-HBV e antigen (anti-HBe). A number of serum samples (264, 263, 224, and 202 for HBsAg, anti-HBs, HBeAg, and anti-HBe, respectively) were studied. For samples giving discrepant results for HBeAg between methods, real-time PCR assays were performed. The concordance rates among the three methods were high for HBsAg (100%) and HBeAg (94.6), but low for anti-HBs (91.6%) and anti-HBe (82.2%). For anti-HBs, which could be measured quantitatively by the Modular E170 and Architect i2000 procedures, discrepant results were observed at low levels of anti-HBs. For anti-HBe, the positive rate was highest with Modular E170 (60.9%) followed by the IRMA kit (54.1%) and Architect i2000 (51.0%). This study shows substantial differences between the assay results by the three methods, which should be taken into account in determinations of serum HBV markers.

Use of polymerase chain reaction for the detection of Chlamydia trachomatis in ocular and nasopharyngeal specimens from infants with conjunctivitis.

PubMed

Hammerschlag, M R; Roblin, P M; Gelling, M; Tsumura, N; Jule, J E; Kutlin, A

1997-03-01

Chlamydia trachomatis is the most common identifiable infectious cause of neonatal conjunctivitis. Nonculture tests including enzyme immunoassays and direct fluorescent antibody tests have been shown to perform well for the diagnosis of chlamydial conjunctivitis with sensitivities and specificities > or = 90%. However, the performance with respiratory specimens has been less than satisfactory. We compared a new, commercially available polymerase chain reaction (PCR) assay, Roche AMPLICOR (Roche Diagnostic Systems, Branchburg, NJ) with culture for the detection of C. trachomatis in conjunctival and nasopharyngeal specimens from infants with conjunctivitis. We also evaluated AMPLICOR for the detection of C. trachomatis in the urine of mothers of positive infants. Ocular and nasopharyngeal specimens from 75 infants with conjunctivitis were obtained for culture and PCR. AMPLICOR was equivalent to culture for eye specimens and more sensitive than culture for nasopharyngeal specimens. The sensitivity, specificity and positive and negative predictive values of PCR compared with culture for conjunctival specimens were 92.3, 100, 100 and 98.4%, respectively. The sensitivity, specificity and positive and negative predictive values for nasopharyngeal specimens were 100, 97.2, 60 and 100%, respectively. We also detected C. trachomatis by PCR in the urine of 12 mothers of culture positive infants. PCR performed comparably to culture for detection of C. trachomatis in conjunctival and nasopharyngeal specimens from infants with conjunctivitis.

VizieR Online Data Catalog: Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2003)

NASA Astrophysics Data System (ADS)

Ritter, H.; Kolb, U.

2004-03-01

Cataclysmic Binaries are semi-detached binaries consisting of a white dwarf or a white dwarf precursor primary and a low-mass secondary which is filling its critical Roche lobe. The secondary is not necessarily unevolved, it may even be a highly evolved star as for example in the case of the AM CVn-type stars. Low-Mass X-Ray Binaries are semi-detached binaries consisting of either a neutron star or a black hole primary, and a low-mass secondary which is filling its critical Roche lobe. Related Objects are detached binaries consisting of either a white dwarf or a white dwarf precursor primary and of a low-mass secondary. The secondary may also be a highly evolved star. The catalogue lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components and other characteristic properties of 522 cataclysmic binaries, 75 low-mass X-ray binaries and 117 related objects with known or suspected orbital periods together with a comprehensive selection of the relevant recent literature. In addition the catalogue contains a list of references to published finding charts for 695 of the 714 objects. A cross-reference list of alias object designations concludes the catalogue. Literature published before 31 December 2003 has, as far as possible, been taken into account. This catalogue supersedes the 5th edition (catalogue ) and the updated lists by Ritter and Kolb (1995; catalogue ) (1998; catalogue ). (10 data files).

VizieR Online Data Catalog: Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2003)

NASA Astrophysics Data System (ADS)

Ritter, H.; Kolb, U.

2005-03-01

Cataclysmic Binaries are semi-detached binaries consisting of a white dwarf or a white dwarf precursor primary and a low-mass secondary which is filling its critical Roche lobe. The secondary is not necessarily unevolved, it may even be a highly evolved star as for example in the case of the AM CVn-type stars. Low-Mass X-Ray Binaries are semi-detached binaries consisting of either a neutron star or a black hole primary, and a low-mass secondary which is filling its critical Roche lobe. Related Objects are detached binaries consisting of either a white dwarf or a white dwarf precursor primary and of a low-mass secondary. The secondary may also be a highly evolved star. The catalogue lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components and other characteristic properties of 572 cataclysmic binaries, 80 low-mass X-ray binaries and 142 related objects with known or suspected orbital periods together with a comprehensive selection of the relevant recent literature. In addition the catalogue contains a list of references to published finding charts for 761 of the 794 objects. A cross-reference list of alias object designations concludes the catalogue. Literature published before 31 December 2004 has, as far as possible, been taken into account. This catalogue supersedes the 5th edition (catalogue ) and the updated lists by Ritter and Kolb (1995; catalogue ) (1998; catalogue ). (10 data files).

Use of the Real Time xCelligence System for Purposes of Medical Microbiology.

PubMed

Junka, Adam Feliks; Janczura, Adriana; Smutnicka, Danuta; Mączyńska, Beata; Anna, Secewicz; Nowicka, Joanna; Bartoszewicz, Marzenna; Gościniak, Grażyna

2012-09-28

Roche's xCelligence impedance-measuring instrument is one of a few commercially available systems of such type. According to the best knowledge of authors, instrument was tested so far only for eukaryotic cell research. The aim of this work was to estimate xCELLigence suitability for the microbiological tests, including (i) measurement of morphological changes in eukaryotic cells as a result of bacterial toxin activity, (ii) measurement of bacterial biofilm formation and (iii) impact of antiseptics on the biofilm structure. To test the infuence of bacterial LT enterotoxin on eukaryotic cell lines, Chinese Hamster Ovary (CHO) cell line and reference strain Escherichia coli ATTC 35401 were used. To investigate Roche's instrument ability to measure biofilm formation and impact of antiseptics on its development, Staphylococcus aureus ATTC6538 reference strain was used. The data generated during the experiments indicate excellent ability of xCelligence instrument to detect cytopathic effect caused by bacterial LT endotoxin and to detect staphylococcal biofilm formation. However, interpretation of the results obtained during real-time measurement of antiseptic's bactericidal activity against staphylococcal biofilm, caused many difficulties. xCelligence instrument can be used for real-time monitoring of morphological changes in CHO cells treated with bacterial LT enterotoxin and for real-time measurement of staphylococcal biofilm formation in vitro. Further investigation is necessary to confirm suitability of system to analyze antiseptic's antimicrobial activity against biofilm in vitro.

Simultaneous CCD Photometry of Two Eclipsing Binary Stars in Pegasus - Part2: BX Peg

NASA Astrophysics Data System (ADS)

Alton, K. B.

2013-05-01

BX Peg is an overcontact W UMa binary system (P = 0.280416 d) which has been rather well studied, but not fully understood due to complex changes in eclipse timings and light curve variations attributed to star spots. Photometric data collected in three bandpasses (B, V, and Ic) produced nineteen new times of minimum for BX Peg. These were used to update the linear ephemeris and further analyze potential changes in orbital periodicity by examining long-term changes in eclipse timings. In addition, synthetic fitting of light curves by Roche modeling was accomplished with the assistance of three different programs, two of which employ the Wilson-Devinney code. Different spotted solutions were necessary to achieve the best Roche model fits for BX Peg light curves collected in 2008 and 2011. Overall, the long-;term decrease (9.66 × 10-3 sec y-1) in orbital period defined by the parabolic fit of eclipse timing data could arise from mass transfer or angular momentum loss. The remaining residuals from observed minus predicted eclipse timings for BX Peg exhibit complex but non-random behavior. These may be related to magnetic activity cycles and/or the presence of an unseen mass influencing the times of minimum, however, additional minima need to be collected over a much longer timescale to resolve the nature of these complex changes.

Constraining Engine Paradigms of Pre-Planetary Nebulae Using Kinematic Properties of their Outflows

NASA Astrophysics Data System (ADS)

Blackman, E.

2014-04-01

Binary interactions and accretion plausibly conspire to produce the ubiquitous collimated outflows from planetary nebulae (PN) and their presumed pre-planetary nebulae (PPN) progenitors. But which accretion engines are viable? The difficulty in observationally resolving the engines warrants indirect constraints. I discuss how momentum outflow data for PPN can be used to determine the minimum required accretion rate for presumed main sequence (MS) or white dwarf (WD) accretors by comparing to several example accretion rates inferred from published models. While the main goal is to show the method in anticipation of more data and better theoretical constraints, taking the present results at face value already rule out modes of accretion: Bondi-Hoyle Lyttleton (BHL) wind accretion and wind Roche lobe overflow (M-WRLOF, based on Mira parameters) are too feeble for all 19/19 objects for a MS accretor. For a WD accretor, BHL is ruled out for 18/19 objects and M-WRLOF for 15/19 objects. Roche lobe overflow from the primary can accommodate 7/19 objects but only common envelope evolution accretion modes seem to be able to accommodate all 19 objects. Sub-Eddington rates for a MS accretor are acceptable but 8/19 would require super-Eddington rates for a WD. I also briefly discuss a possible anti-correlation between age and maximum observed outflow speed, and the role of magnetic fields.

Validation of Roche LightCycler Epstein-Barr virus quantification reagents in a clinical laboratory setting.

PubMed

Gulley, Margaret L; Fan, Hongxin; Elmore, Sandra H

2006-11-01

Epstein-Barr virus (EBV) is associated with a wide range of benign and malignant diseases, including infectious mononucleosis, lymphoma, posttransplant lymphoproliferative disorder, and nasopharyngeal carcinoma. Measurement of EBV viral load in plasma is increasingly used for rapid assessment of disease status. We evaluated the performance characteristics of an EBV polymerase chain reaction assay that uses commercial reagents and instruments from Roche Diagnostics (Indianapolis, IN). DNA was extracted from plasma using a MagNaPure instrument, and viral load was measured by real-time polymerase chain reaction on a LightCycler. Analyte-specific reagents included primers and hybridization probes targeting the EBV LMP2 gene and a spiked control sequence. Accuracy and reproducibility were established using DNA from three cell lines. The assay was sensitive to approximately 750 copies of EBV DNA per milliliter of plasma and was linear across at least four orders of magnitude. The assay detected EBV DNA in three of five samples from nasopharyngeal carcinoma patients, seven of nine infectious mononucleosis samples, and 34/34 samples from immunosuppressed patients with clinically significant EBV-related disease, whereas EBV DNA was undetectable in plasma from 21 individuals without EBV-related disease. In conclusion, this LightCycler EBV assay is rapid, sensitive, and linear for quantifying EBV viral load. The assay appears to be useful for measuring clinically significant EBV levels in immunodeficient patients.

Assay of anti-HBs antibodies using a recombinant antigen and latex particle counting: comparison with five commercial tests.

PubMed

Galanti, L M; Cornu, C; Masson, P L; Robert, A R; Becheanu, D; Lamy, M E; Cambiaso, C L

1991-05-01

An assay of anti-HBs antibodies based on agglutination of latex particles coated with recombinant HBs-antigen was compared with Abbott radioimmunoassay (Abbott-RIA), which uses a human plasma-derived antigen. The population examined consisted of 76 Abbott-RIA anti-HBs-negative prevaccinated subjects and 1044 serum samples anti-HBs found positive by Abbott-RIA, including 283 samples of subjects vaccinated either with a human plasma-derived vaccine (group A; n = 180) or with a recombinant vaccine (group B; n = 103). Correlation coefficients between the two techniques were respectively r = 0.89 for the whole population (n = 1044), r = 0.98 in group A and r = 0.74 in group B. Anti-HBs titres were higher with latex than with RIA in group B as shown by the regression slopes: latex = 508 + 1.11 RIA in group A and latex = -1138 + 3.97 RIA in group B, suggesting that some vaccinated subjects from group B produced antibodies against epitopes proper to the recombinant antigen. In the prevaccinated population and in group A, the latex results were compared with those of radioimmunoassays (Abbott, Sorin) and enzyme immunoassays (Behring, Roche, Pasteur). Only the Roche-EIA detected anti-HBs in the prevaccinated subjects. The correlation between the various immunoassays was r greater than 0.96 only for values higher than 100 IU/l.

Detection and identification of occult HBV in blood donors in Taiwan using a commercial, multiplex, multi-dye nucleic acid amplification technology screening test.

PubMed

Lin, K T; Chang, C L; Tsai, M H; Lin, K S; Saldanha, J; Hung, C M

2014-02-01

The ability of a new generation commercial, multiplex, multi-dye test from Roche, the cobas TaqScreen MPX test, version 2.0, to detect and identify occult HBV infections was evaluated using routine donor samples from Kaohsiung Blood Bank, Taiwan. A total of 5973 samples were tested by nucleic acid amplification technology (NAT); 5898 in pools of six, 66 in pools of less than six and nine samples individually. NAT-reactive samples were retested with alternative NAT tests, and follow-up samples from the donors were tested individually by NAT and for all the HBV serological markers. Eight NAT-only-reactive donors were identified, and follow-up samples were obtained from six of the donors. The results indicated that all eight donors had an occult HBV infection with viral loads <12 IU/ml. The cobas(®) TaqScreen MPX test, version 2.0, has an advantage over the current Roche blood screening test, the cobas TaqScreen MPX test, for screening donations in countries with a high prevalence of occult HBV infections since the uncertainty associated with identifying samples with very low viremia is removed by the ability of the test to identify the viral target in samples that are reactive with the cobas TaqScreen MPX test, version 2.0. © 2013 International Society of Blood Transfusion.

Presence of human papillomavirus in semen in relation to semen quality.

PubMed

Luttmer, Roosmarijn; Dijkstra, Maaike G; Snijders, Peter J F; Hompes, Peter G A; Pronk, Divera T M; Hubeek, Isabelle; Berkhof, Johannes; Heideman, Daniëlle A M; Meijer, Chris J L M

2016-02-01

Is the presence of human papillomavirus (HPV) in semen associated with impairment of semen quality? In a large cohort of males seeking fertility evaluation, no associations were observed between seminal HPV presence and semen parameters. HPV is commonly detected in semen samples. Whether the presence of HPV is related to impairment of semen quality, remains unclear. This cross-sectional study included a cohort of 430 males. Male partners in couples seeking fertility evaluation provided one semen sample per person. Semen samples were tested for HPV-DNA using GP5+/6+-PCR. Sperm concentration was counted and motility was assessed in a Makler counting chamber at a magnification of ×200. The presence of antisperm antibodies was assessed by a mixed agglutination reaction (MAR)-test. Overall HPV was detected in 14.9% (64/430) of semen samples, including 2.1% (9/430) that contained both high-risk (hr) HPV and low-risk (lr) HPV types, 8.8% (38/430) with exclusively hrHPV types and 4.0% (17/430) with exclusively lrHPV types. The presence of HPV in semen was not associated with the age of the participants, seminal pH, semen volume, total sperm count, sperm concentration, progressive motility or the presence of antisperm antibodies. This study did not observe an association between HPV presence in semen and impairment of semen quality. However, we cannot exclude an effect of seminal HPV on early embryo development and clinical reproductive outcomes. As HPV is frequently present in semen, screening of donor semen for HPV should be considered to prevent iatrogenic cervical HPV infections in the recipient. However our findings do not support standardized HPV testing of semen in the diagnostic work-up of subfertile couples. This study was sponsored by an unrestricted grant of Stichting Researchfonds Pathology Amsterdam, the Netherlands. P.J.F.S. has been on the speakers bureau of Roche, Gen-Probe, Abbott, Qiagen and Seegene and has been a consultant for Crucell B.V. J.B. has been on the speakers bureau of Qiagen and has been a consultant for Roche, DDL Diagnostic Laboratory, GlaxoSmithKline and Merck. D.A.M.H. has been member of the scientific advisory boards of Amgen and Pfizer, and has been on the speakers bureau of Hologic/Gen-Probe. C.J.L.M.M. has been on the speakers bureau of GlaxoSmithKline, Qiagen, Merck, Roche, Menarini and Seegene, has served occasionally on the scientific advisory board of GlaxoSmithKline, Qiagen, Merck, Roche and Genticel, and has occasionally been a consultant for Qiagen. Formerly, C.J.L.M.M. was a minority shareholder of Delphi Biosciences, which bankrupted in 2014. C.J.L.M.M. is a minority shareholder of Diassay B.V. P.J.F.S., D.A.M.H. and C.J.L.M.M. have minority stake in Self-Screen B.V., a spin-off company of VU University Medical Center. R.L., M.G.D., P.G.A.H., D.T.M.P., and I.H. do not have any conflicts of interest to disclose. Not applicable. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Adiabatic Mass Loss Model in Binary Stars

NASA Astrophysics Data System (ADS)

Ge, H. W.

2012-07-01

Rapid mass transfer process in the interacting binary systems is very complicated. It relates to two basic problems in the binary star evolution, i.e., the dynamically unstable Roche-lobe overflow and the common envelope evolution. Both of the problems are very important and difficult to be modeled. In this PhD thesis, we focus on the rapid mass loss process of the donor in interacting binary systems. The application to the criterion of dynamically unstable mass transfer and the common envelope evolution are also included. Our results based on the adiabatic mass loss model could be used to improve the binary evolution theory, the binary population synthetic method, and other related aspects. We build up the adiabatic mass loss model. In this model, two approximations are included. The first one is that the energy generation and heat flow through the stellar interior can be neglected, hence the restructuring is adiabatic. The second one is that he stellar interior remains in hydrostatic equilibrium. We model this response by constructing model sequences, beginning with a donor star filling its Roche lobe at an arbitrary point in its evolution, holding its specific entropy and composition profiles fixed. These approximations are validated by the comparison with the time-dependent binary mass transfer calculations and the polytropic model for low mass zero-age main-sequence stars. In the dynamical time scale mass transfer, the adiabatic response of the donor star drives it to expand beyond its Roche lobe, leading to runaway mass transfer and the formation of a common envelope with its companion star. For donor stars with surface convection zones of any significant depth, this runaway condition is encountered early in mass transfer, if at all; but for main sequence stars with radiative envelopes, it may be encountered after a prolonged phase of thermal time scale mass transfer, so-called delayed dynamical instability. We identify the critical binary mass ratio for the onset of dynamical time scale mass transfer; if the ratio of donor to accretor masses exceeds this critical value, the dynamical time scale mass transfer ensues. The grid of criterion for all stars can be used to be the basic input as the binary population synthetic method, which will be improved absolutely. In common envelope evolution, the dissipation of orbital energy of the binary provides the energy to eject the common envelope; the energy budget for this process essentially consists of the initial orbital energy of the binary and the initial binding energies of the binary components. We emphasize that, because stellar core and envelope contribute mutually to each other's gravitational potential energy, proper evaluation of the total energy of a star requires integration over the entire stellar interior, not the ejected envelope alone as commonly assumed. We show that the change in total energy of the donor star, as a function of its remaining mass along an adiabatic mass-loss sequence, can be calculated. This change in total energy of the donor star, combined with the requirement that both remnant donor and its companion star fit within their respective Roche lobes, then circumscribes energetically possible survivors of common envelope evolution. It is the first time that we can calculate the accurate total energy of the donor star in common envelope evolution, while the results with the old method are inconsistent with observations.

Evaluating of the Anticonvulsant Gabapentin against Nerve Agent-Induced Seizures in a Guinea Pig Model

DTIC Science & Technology

2010-07-01

from Cutter Labs, Inc. (Berkeley, CA). Pyridostigmine bromide was obtained from Hoffmann- La Roche, Inc. (Nutley, NJ), and pyridine-2-aldoxime... Pyridostigmine bromide was prepared in sterile water to a concentration of 0.052 mg/ml. Atropine sulfate (4 mg/ml) and 2-PAM (50 mg/ml) were prepared in...activity. After a week recovery, animals were pretreated with pyridostigmine 30 min prior to subcutaneous soman challenge (56 ug/kg; 2 X LD50

Imaging Stellar Surface with The CHARA Array

NASA Astrophysics Data System (ADS)

Schaefer, Gail

2018-04-01

I will provide an overview of results on imaging stellar surfaces with the CHARA Array. These include imaging gravity darkening on rapid rotators, starspots on magnetically active stars, convective cells on red supergiants, and stellar winds from massive stars. In binary systems, the CHARA Array has been used to observe tidal distortions from Roche lobe filling in interactive binaries, transiting companions as they move through eclipse, and the angular expansion of novae explosions. I will discuss the impact of these results in an astrophysical context.

American Peptide Symposium Proceedings (13th) Held in Edmonton, Alberta, Canada on June 20-25, 1993. Peptides: Chemistry, Structure and Biology

DTIC Science & Technology

1993-06-20

La Roche, Inc. Vydac/The SEP/A/RA/IIONS Group, Inc. DONORS BioChem Pharma , Inc. Biomeasure Incorporated Boehringer Mannheim GmbH Bristol-Myers Squibb...Alberta Tourism, Parks and Recreation Astra Pharma , Inc. Bio-Mega, Inc. Ciba-Geigy Canada, Inc. CSPS Cytogen Edmonton Convention and Tourist Authority...Van der Walle, C. Toomey and L Toth Design and synthesis of poly-tricosapeptides to enhance hydrophobic- induced pKa shifts 940 D.C. Gowda, T.M

Glider-based Passive Acoustic Monitoring Techniques in the Southern California Region & West Coast Naval Training Range Demonstration of Glider-based Passive Acoustic Monitoring

DTIC Science & Technology

2012-09-30

generalized power-law detection algorithm for humpback whale vocalizations. J. Acous. Soc. Am. 131(4), 2682-2699. Roch, M. A., H. Klinck, S...Heaney (2012b). Site specific probability of passive acoustic detection of humpback whale calls from single fixed hydrophones. J. Acous. Soc. Am...monitoring: Correcting humpback call detections for site-specific and time-dependent environmental characteristics . JASA Express Letters, submitted October, 2012, 5 pgs plus 3 figs.

Usutu virus infections among blood donors, Austria, July and August 2017 - Raising awareness for diagnostic challenges.

PubMed

Bakonyi, Tamás; Jungbauer, Christof; Aberle, Stephan W; Kolodziejek, Jolanta; Dimmel, Katharina; Stiasny, Karin; Allerberger, Franz; Nowotny, Norbert

2017-10-01

Between July and August 2017, seven of 12,047 blood donations from eastern Austria, reacted positive to West Nile virus (WNV) in the cobas test (Roche). Follow-up investigations revealed Usutu virus (USUV) nucleic acid in six of these. Retrospective analyses of four blood donors diagnosed as WNV-infected in 2016 showed one USUV positive. Blood transfusion services and public health authorities in USUV-endemic areas should be aware of a possible increase of human USUV infections.

Modeling of Habitat and Foraging Behavior of Beaked Whales in the Southern California Bight

DTIC Science & Technology

2012-09-30

patterns of beaked whale echolocation signals in the North Pacific over 26 sites (Figure 3) (Baumann-Pickering et al., 2012a) revealed that Wake Atoll ... Atoll are not considered typical territory for this species and would be a surprising finding. BW43 signal encounters were restricted to the...Roch, M. A., Schnitzler, H. U., and Hildebrand, J. A. (2010). "Echolocation signals of a beaked whale at Palmyra Atoll ," J. Acoust. Soc. Am. 127

The Journal Microarrays

PubMed Central

Lin, Shu-Kun

2011-01-01

Our publishing company MDPI AG has its headquarters in Basel, Switzerland where there are thousands of scientists working in the laboratories of pharmaceutical companies and institutes including Novartis [1], F. Hoffmann-La Roche [2] and institutes affiliated with University of Basel [3]. In 1996, the first annual microplate conference MipTec was held in Basel, and the MipTec 2011 was held a few days ago in Basel [4]. I published a paper on microplate standardization presented at MipTec 1996 in MDPI’s longest-running journal Molecules [5-7]. [....] PMID:27605331

Studies of an x ray selected sample of cataclysmic variables. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Silber, Andrew D.

1986-01-01

Just prior to the thesis research, an all-sky survey in hard x rays with the HEAO-1 satellite and further observations in the optical resulted in a catalog of about 700 x-ray sources with known optical counterparts. This sample includes 43 cataclysmic variables, which are binaries consisting of a detached white-dwarf and a Roche lobe filling companion star. This thesis consists of studies of the x-ray selected sample of catalcysmic variables.

The Journal Microarrays.

PubMed

Lin, Shu-Kun

2011-10-14

Our publishing company MDPI AG has its headquarters in Basel, Switzerland where there are thousands of scientists working in the laboratories of pharmaceutical companies and institutes including Novartis [1], F. Hoffmann-La Roche [2] and institutes affiliated with University of Basel [3]. In 1996, the first annual microplate conference MipTec was held in Basel, and the MipTec 2011 was held a few days ago in Basel [4]. I published a paper on microplate standardization presented at MipTec 1996 in MDPI's longest-running journal Molecules [5-7]. [....].

Millimeter Wave Communications Program: Link Tests of High Speed Digital Radio Set AN/GRC-173 (XW-1)

DTIC Science & Technology

1975-01-01

Terrence Kelly, John Mutty, Edward Rich, James Roche, William J. Smxth, Carson Tsao, and David Trask. Hugh N. Siegel (DCCW) was the RADC...shelter, except for the parabolic dish and front-feed antenna system, which is mast-mounted adjacent to the shelter and connected to an rf input...Equipment: All rf and digital units 8. POWER SUPPLIES Quantity: 1 for rf , 1 for digital Primary Power: 120/240V +10% single phase, 47 - 420 Hz

Resolving components of wind accreting systems: a case study of Mira AB

NASA Astrophysics Data System (ADS)

Karovska, M.

2004-12-01

Mass transfer in many systems occurs by wind interaction rather then by tidal interaction, because the primary does not fill its Roche surface. The nearby detached binary Mira AB provides a unique laboratory for studying wind accretion processes because this system can be resolved and the interacting components can be studied individually, which is not possible in most accreting systems. The study of Mira AB wind accretion and mass transfer may therefore help understand the accretion processes in many other astronomical systems.

Draft Genome Sequence of Streptomyces clavuligerus NRRL 3585, a Producer of Diverse Secondary Metabolites▿

PubMed Central

Song, Ju Yeon; Jeong, Haeyoung; Yu, Dong Su; Fischbach, Michael A.; Park, Hong-Seog; Kim, Jae Jong; Seo, Jeong-Sun; Jensen, Susan E.; Oh, Tae Kwang; Lee, Kye Joon; Kim, Jihyun F.

2010-01-01

Streptomyces clavuligerus is an important industrial strain that produces a number of antibiotics, including clavulanic acid and cephamycin C. A high-quality draft genome sequence of the S. clavuligerus NRRL 3585 strain was produced by employing a hybrid approach that involved Sanger sequencing, Roche/454 pyrosequencing, optical mapping, and partial finishing. Its genome, comprising four linear replicons, one chromosome, and four plasmids, carries numerous sets of genes involved in the biosynthesis of secondary metabolites, including a variety of antibiotics. PMID:20889745

Pioneer 10 and 11 radio occultations by Jupiter. [atmospheric temperature structure

NASA Technical Reports Server (NTRS)

Kliore, A. J.; Woiceshyn, P. M.; Hubbard, W. B.

1977-01-01

Results on the temperature structure of the Jovian atmosphere are reviewed which were obtained by applying an integral inversion technique combined with a model for the planet's shape based on gravity data to Pioneer 10 and 11 radio-occultation data. The technique applied to obtain temperature profiles from the Pioneer data consisted of defining a center of refraction based on a computation of the radius of curvature in the plane of refraction and the normal direction to the equipotential surface at the closest approach point of a ray. Observations performed during the Pioneer 10 entry and exit and the Pioneer 11 exit are analyzed, sources of uncertainty are identified, and representative pressure-temperature profiles are presented which clearly show a temperature inversion between 10 and 100 mb. Effects of zonal winds on the reliability of radio-occultation temperature profiles are briefly discussed.

High mass resolution isochronous time-of-flight spectrograph for three-dimensional space plasma measurements

NASA Technical Reports Server (NTRS)

Moebius, E.; Bochsler, P.; Ghielmetti, A. G.; Hamilton, D. C.

1990-01-01

By combining a toroidal electrostatic analyzer with a novel cylindrically symmetric isochronous time-of-flight mass spectrometer, an instrument was developed that simultaneously determines the three-dimensional distribution function of ions and differentiates species. The ion mass is determined to high resolution (M/Delta-M greater than 50) from the time of flight within a harmonic field configuration defined by hyperboloid equipotential surfaces. A second conventional time-of-flight channel makes use of particles leaving the thin entrance foil as neutrals. An additional solid state detector in which the neutrals are stopped allows the total energy and thereby the ionic charge of the incident ions to be determined as well. Information from the neutral and the ion channels can be combined to determine the total mass of an incident molecular ion and the mass of one atomic fragment.

The moment of inertia and isostasy of Mars

NASA Technical Reports Server (NTRS)

Reasenberg, R. D.

1977-01-01

The systematic and large deviation of the gravitational equipotential surface (EPS) of Mars from a spheroid of revolution suggests a description of Mars in terms of a spheroid nearly in isostatic equilibrium with an extra mass in the Tharsis region. The displacement from Mars and the shape of the spheroid are calculated by using this description and a Mars gravity model. The EPS is represented as a contour map of its height above the spheroid. This representation provides the first clear demonstration that the Hellas depression coincides with a depression in the EPS. The disequilibrium contribution of Tharsis to the coefficient J2 of the second-degree harmonics of gravitational potential of Mars is estimated to be (126 + or - 5) times 10 to the minus 6th. The optical flattening and dynamic flattening calculated on this basis are in substantially better agreement than are those calculated in the usual way.

Anisotropic conductivity imaging with MREIT using equipotential projection algorithm.

PubMed

Değirmenci, Evren; Eyüboğlu, B Murat

2007-12-21

Magnetic resonance electrical impedance tomography (MREIT) combines magnetic flux or current density measurements obtained by magnetic resonance imaging (MRI) and surface potential measurements to reconstruct images of true conductivity with high spatial resolution. Most of the biological tissues have anisotropic conductivity; therefore, anisotropy should be taken into account in conductivity image reconstruction. Almost all of the MREIT reconstruction algorithms proposed to date assume isotropic conductivity distribution. In this study, a novel MREIT image reconstruction algorithm is proposed to image anisotropic conductivity. Relative anisotropic conductivity values are reconstructed iteratively, using only current density measurements without any potential measurement. In order to obtain true conductivity values, only either one potential or conductivity measurement is sufficient to determine a scaling factor. The proposed technique is evaluated on simulated data for isotropic and anisotropic conductivity distributions, with and without measurement noise. Simulation results show that the images of both anisotropic and isotropic conductivity distributions can be reconstructed successfully.

An improved design of electrodes for measurement of streaming potentials on wet bone in vitro and in vivo.

PubMed

Cochran, G V; Dell, D G; Palmieri, V R; Johnson, M W; Otter, M W; Kadaba, M P

1989-01-01

Streaming potentials are generated by mechanical stress in wet bone and may constitute a control mechanism for bone remodeling. Measurement of streaming potentials in bone has attracted considerable effort in past years but quantitative studies have been hampered by relatively poor repeatability when using Ag.AgCl electrodes which contact bone via a wick moistened with electrolyte. Improvement now has been achieved with an electrode design that limits the specific area of contact of an agar/salt bridge by means of a silastic seal, thus permitting the same equipotential surface to be contacted for each set of measurements. This reduces variations caused by bone structure and impedance, and facilitates quantitative comparisons of the response of bone samples to selected variables. The new design also permits considerable qualitative improvement in recordings made from bone during locomotor function in experimental animals in vivo.

Altered epidermal growth factor-like sequences provide evidence for a role of Notch as a receptor in cell fate decisions.

PubMed

Heitzler, P; Simpson, P

1993-03-01

In Drosophila each neural precursor is chosen from a group of cells through cell interactions mediated by Notch and Delta which may function as receptor and ligand (signal), respectively, in a lateral signalling pathway. The cells of a group are equipotential and express both Notch and Delta. Hyperactive mutant Notch molecules, (Abruptex), probably have an enhanced affinity for the ligand. When adjacent to wild-type cells, cells bearing the Abruptex proteins are unable to produce the signal. It is suggested that in addition to the binding of Notch molecules on one cell to the Delta molecules of opposing cells, the Notch and Delta proteins on the surface of the same cell may interact. Binding between a cell's own Notch and Delta molecules would alter the availability of these proteins to interact with their counterparts on adjacent cells.

I-BIEM calculations of the frequency dispersion and ac current distribution at disk and ring-disk electrodes

NASA Technical Reports Server (NTRS)

Cahan, Boris D.

1991-01-01

The Iterative Boundary Integral Equation Method (I-BIEM) has been applied to the problem of frequency dispersion at a disk electrode in a finite geometry. The I-BIEM permits the direct evaluation of the AC potential (a complex variable) using complex boundary conditions. The point spacing was made highly nonuniform, to give extremely high resolution in those regions where the variables change most rapidly, i.e., in the vicinity of the edge of the disk. Results are analyzed with respect to IR correction, equipotential surfaces, and reference electrode placement. The current distribution is also examined for a ring-disk configuration, with the ring and the disk at the same AC potential. It is shown that the apparent impedance of the disk is inductive at higher frequencies. The results are compared to analytic calculations from the literature, and usually agree to better than 0.001 percent.

I-BIEM calculations of the frequency dispersion and AC current distribution at disk and ring-disk electrodes

NASA Technical Reports Server (NTRS)

Cahan, Boris D.

1991-01-01

The Iterative Boundary Integral Equation Method (I-BIEM) has been applied to the problem of frequency dispersion at a disk electrode in a finite geometry. The I-BIEM permits the direct evaluation of the AC potential (a complex variable) using complex boundary conditions. The point spacing was made highly nonuniform, to give extremely high resolution in those regions where the variables change most rapidly, i.e., in the vicinity of the edge of the disk. Results are analyzed with respect to IR correction, equipotential surfaces, and reference electrode placement. The current distribution is also examined for a ring-disk configuration, with the ring and the disk at the same AC potential. It is shown that the apparent impedance of the disk is inductive at higher frequencies. The results are compared to analytic calculations from the literature, and usually agree to better than 0.001 percent.

Topographic Constraints on the Evolution and Connectivity of Titan's Lacustrine Basins

NASA Astrophysics Data System (ADS)

Hayes, A. G.; Birch, S. P. D.; Dietrich, W. E.; Howard, A. D.; Kirk, R. L.; Poggiali, V.; Mastrogiuseppe, M.; Michaelides, R. J.; Corlies, P. M.; Moore, J. M.; Malaska, M. J.; Mitchell, K. L.; Lorenz, R. D.; Wood, C. A.

2017-12-01

The topography provided by altimetry, synthetic aperture radar-topography, and stereo radargrammetry has opened new doors for Titan research by allowing for quantitative analysis of morphologic form. Using altimetry measurements, we show that Titan's Maria are consistent with an equipotential surface but that several filled lakes are found to be hundreds of meters above this sea level, suggesting that they exist in isolated or perched basins. Within a given drainage basin, empty lake floors are typically higher than the liquid elevation of nearby lakes/seas, suggesting local subsurface connectivity. The majority of Titan's lakes reside in topographically closed, sharp-edged depressions whose planform curvature suggests lateral expansion through uniform scarp retreat. Many, but not all, empty lake basins exhibit flat floors and hectometer-scale raised rims that present a challenge to formation models. We conclude that dissolution erosion can best match the observed constraints but that challenges remain in the interpretation of formation processes and materials.

Simulation of radial expansion of an electron beam injected into a background plasma

NASA Technical Reports Server (NTRS)

Koga, J.; Lin, C. S.

1989-01-01

A 2-D electrostatic particle code was used to study the beam radial expansion of a nonrelativistic electron beam injected from an isolated equipotential conductor into a background plasma. The simulations indicate that the beam radius is generally proportional to the beam electron gyroradius when the conductor is charged to a large potential. The simulations also suggest that the charge buildup at the beam stagnation point causes the beam radial expansion. From a survey of the simulation results, it is found that the ratio of the beam radius to the beam electron gyroradius increases with the square root of beam density and decreases inversely with beam injection velocity. This dependence is explained in terms of the ratio of the beam electron Debye length to the ambient electron Debye length. These results are most applicable to the SEPAC electron beam injection experiments from Spacelab 1, where high charging potential was observed.

Ion extraction from a plasma. Ph.D. Thesis. Progress Report, 1 Dec. 1979 - 1 Dec. 1980

NASA Technical Reports Server (NTRS)

Aston, G.

1980-01-01

An experimental investigation of the physical processes governing ion extraction from a plasma is presented. The screen hole plasma sheath of a multiaperture ion accelerator system is defined by equipotential plots for a variety of accelerator system geometries and operating conditions. A sheath thickness of at least fifteen Debye lengths is shown to be typical. The electron density variation within the sheath satisfies a Maxwell Boltzmann density distribution at an effective electron temperature dependent on the discharge plasma primary to Maxwellian electron density ratio. Plasma ion flow up to and through the sheath is predominately one dimensional and the ions enter the sheath with a modified Bohm velocity. Low values of the screen grid thickness to screen hole diameter ratio give good ion focusing and high extracted ion currents because of the effect of screen webbing on ion focusing.

The Circle of Apollonius and Its Applications in Introductory Physics

NASA Astrophysics Data System (ADS)

Partensky, Michael B.

2008-02-01

The circle of Apollonius is named after the ancient geometrician Apollonius of Perga. This beautiful geometric construct can be helpful when solving some general problems of geometry and mathematical physics, optics, and electricity. Here we discuss two of its applications: localizing an object in space and calculating electric fields. First, we pose an entertaining localization problem to trigger students' interest in the subject. Analyzing this problem, we introduce the circle of Apollonius and show that this geometric technique helps solve the problem in an elegant and intuitive manner. Then we switch to seemingly unrelated problems of calculating the electric fields. We show that the zero equipotential line for two unlike charges is the Apollonius circle for these two charges and use this discovery to find the electric field of a charge positioned near a grounded conductive sphere. Finally, we pose some questions for further examination.

Some new concepts in the n-body and 3-body problems

NASA Astrophysics Data System (ADS)

Kyrala, A.

1982-06-01

A new approach to the n-body problem in terms of an rms particle velocity and a harmonic mean particle separation has been constructed by using averaging procedures formulated in terms of a single parameter. A systematic classification of escape and collision processes by means of specific polynomials, which can be used somewhat like generating functions, is introduced. For n-body problems with non-null total angular momentum, an rms angular momentum is defined which together with a harmonic mean centroidal moment of inertia characterizes the rotational kinetic energy. Finally, a graphical construction for the equipotentials of the three-body problem is given and attention is drawn to the use of the apex, defined as the point of least average separation, in this problem. It is supposed that the n-bodies interact with one another via the Newtonian potential in an inertial system.

How do octopuses use their arms?

PubMed

Mather, J A

1998-09-01

A taxonomy of the movement patterns of the 8 flexible arms of octopuses is constructed. Components consist of movements of the arm itself, the ventral suckers and their stalks, as well as the relative position of arms and the skin web between them. Within 1 arm, combinations of components result in a variety of behaviors. At the level of all arms, 1 group of behaviors is described as postures, on the basis of the spread of all arms and the web to make a 2-dimensional surface whose position differs in the 3rd dimension. Another group of arm behaviors is actions, more or less coordinated and involving several to all arms. Arm control appears to be based on radial symmetry, relative equipotentiality of all arms, relative independence of each arm, and separability of components within the arm. The types and coordination of arm behaviors are discussed with relationship to biomechanical limits, muscle structures, and neuronal programming.

Trends, prospects and challenges in quantifying flow and transport through fractured rocks

NASA Astrophysics Data System (ADS)

Neuman, Shlomo P.

2005-03-01

Among the current problems that hydrogeologists face, perhaps there is none as challenging as the characterization of fractured rock (Faybishenko and Benson 2000). This paper discusses issues associated with the quantification of flow and transport through fractured rocks on scales not exceeding those typically associated with single- and multi-well pressure (or flow) and tracer tests. As much of the corresponding literature has focused on fractured crystalline rocks and hard sedimentary rocks such as sandstones, limestones (karst is excluded) and chalk, so by default does this paper. Direct quantification of flow and transport in such rocks is commonly done on the basis of fracture geometric data coupled with pressure (or flow) and tracer tests, which therefore form the main focus. Geological, geophysical and geochemical (including isotope) data are critical for the qualitative conceptualization of flow and transport in fractured rocks, and are being gradually incorporated in quantitative flow and transport models, in ways that this paper unfortunately cannot describe but in passing. The hydrogeology of fractured aquifers and other earth science aspects of fractured rock hydrology merit separate treatments. All evidence suggests that rarely can one model flow and transport in a fractured rock consistently by treating it as a uniform or mildly nonuniform isotropic continuum. Instead, one must generally account for the highly erratic heterogeneity, directional dependence, dual or multicomponent nature and multiscale behavior of fractured rocks. One way is to depict the rock as a network of discrete fractures (with permeable or impermeable matrix blocks) and another as a nonuniform (single, dual or multiple) continuum. A third way is to combine these into a hybrid model of a nonuniform continuum containing a relatively small number of discrete dominant features. In either case the description can be deterministic or stochastic. The paper contains a brief assessment of these trends in light of recent experimental and theoretical findings, ending with a short list of prospects and challenges for the future. Parmis les problèmes aucquels font face les hydrogéologues, il y a celui de la caractérisation des roches fracturées (Faybishenko and Benson, 2000). Cet article discute des solutions associées aux quantifications des écoulements et des transports à travers les roches fracturées à l'échelles des essais de puits et des essais de traçage. Une part importante de la litérature traite des roches cristallines, des roches sédimentaires consolidées telles les grés, les calcaires (exeptés les karsts) et la craie. De fait, cet article traitera la même panoplie de roches. La quantification directe des écoulements et du transport dans de tels milieux est généralement abordée via la géométrie des fractures, les données de pression et de traçage, qui déslors sont les objets principaux de notre étude. La géologie, la géophysique et la géochimie (incluant la géochimie isotopique) sont criticables car elles donnent des informations qualitatives sur l'écoulement et le transport des aquifères fracturés, et son intégrées graduellement dans des modèles qualitatifs. La manière d'intégrer ces données dépasse malheureusement cet article. L'hydrogéologie des aquifères de fractures et les autres sciences de la terre s'intéressant aux roches fracturées méritent des traîtements différents. En toute évidence il est suggéré que rarement un modèle d'écoulement et de transport dans une roche fracturée puisse être traité comme un milieu isotropique continu, uniforme ou moyennement non-uniforme. Par ailleurs, il est admis la dépendance entre la forte hétérogénéité erratique et la variété de natures et de comportements des roches fracturées. Une manière de régler le problème est de considérer le milieu comme un réseau de fractures discrètes (avec une perméabilité de matrice ou de bloc). Une autre est de l'envisager comme un milieu non-uniforme (simple, double ou multiple) continu. Une troisième manière est de combiner ceci dans un modèle hybride d'un milieu non-uniforme, contenant un relativement petit nombre de fractures dominantes et discrètes. Dans d'auters cas la description peut être déterministe ou stochastique. L'article contient un brève apperçu de ces tendances à la lumière d'expériences récentes et de nouvelles théories, et se termine par une courte liste de «challenge» et de priorités pour le futur. Entre los problemas actuales que enfrentan los hidrogeólogos, quizá no hay uno tan desafiante como la caracterización de roca fracturada (Faybishenko y Benson, 2000). Este artículo discute problemas asociados con la cuantificación de flujo y transporte a través de rocas fracturadas en escalas que no exceden las típicas asociadas con presión (o flujo) en un solo pozo o varios pozos y pruebas con trazadores. Debido a que mucha de la literatura del tema se ha enfocado en rocas cristalinas fracturadas y rocas sedimentarias duras tal como areniscas, calizas (excluyendo karst) y creta, también en contumacia lo hace este artículo. La cuantificación directa del flujo y transporte en tales rocas se hace comúnmente en base a datos geométricos de fracturas acoplados con pruebas de presión (o flujo) y trazadores, los cuales por lo tanto constituyen nuestra principal orientación. Datos geológicos, geofísicos y geoquímicos (incluyendo isótopos) son críticos para la conceptualización cuantitativa de flujo y transporte en rocas fracturadas, y se han estado incorporando gradualmente en modelos cuantitativos de flujo y transporte, en formas que desafortunadamente este artículo solo puede describir de paso. La hidrogeología de rocas fracturadas y otros aspectos de ciencia de la tierra de hidrología de rocas fracturadas amerita tratamientos separados. Toda la evidencia sugiere que uno raramente puede modelizar flujo y transporte en una roca consistentemente fracturada si la considera como una unidad continua isotrópica uniforme o poco uniforme. En vez de adoptar este enfoque, uno tiene generalmente que explicar la heterogeneidad altamente errática, dependencia direccional, naturaleza doble o multicomponente y comportamiento multiescalar de las rocas fracturadas. Una manera de lograr esto consiste en considerar que la roca contiene una redde fracturas discretas (con bloques de matriz permeable o impermeable) y otro modo en considerar la roca como una unidad continua no uniforme (sola, doble o múltiple). Un tercer procedimiento consiste en combinar las dos maneras anteriores en un modelo híbrido el cual consiste de un continuo no uniforme conteniendo un número relativamente pequeño de fracturas principalmente discretas. En ambos casos la descripción puede ser determinística o estocástica. El artículo contiene una evaluación breve de estas tendencias en base a descubrimientos recientes teóricos y experimentales, terminando con una lista corta de prospectos y desafíos para el futuro.

Comparison of Abbott AxSYM and Roche Elecsys 2010 for measurement of BNP and NT-proBNP.

PubMed

Chien, Tzu-I; Chen, Hui-Hou; Kao, Jau-Tsuen

2006-07-15

B-type natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are small cardiac hormones released from the heart. They can be used as an important aid to diagnose congestive heart failure (CHF). We compared the performances of the Abbott AxSYM and Roche Elecsys 2010 for the measurement of BNP and NT-proBNP. The first method uses a microparticle enzyme-linked immunoassay, whereas the other uses chemiluminescent immunometric assay. The CVs using pooled sera ranged from 3.7% to 12.7% for the AxSYM and 0.9% to 2.2% for the Elecsys 2010. The Passing and Bablok regression was Elecsys 2010 NT-proBNP=7.23xAxSYM BNP+2.53. The BNP in EDTA plasma was more stable than in serum. The immunoreactivity difference of NT-proBNP in serum or EDTA plasma was within 10% when stored at 4 degrees Celsius or 25 degrees Celsius for 72 h. Receiver operating characteristic (ROC) curves were different for both assays, and the areas under the curves were 0.704 and 0.841 for the AxSYM and Elecsys 2010 method, respectively. Both assays were not entirely specific for heart failure. The precision and stability for NT-proBNP was better than for BNP in serum. It is important to use method-appropriate reference ranges (or cutoff) for the BNP and NT-proBNP, respectively, in the assessment of CHF.

Comparison of MagNA Pure 96, Chemagic MSM1, and QIAamp MinElute for hepatitis B virus nucleic acid extraction.

PubMed

Kang, Seong-Ho; Lee, Eun Hee; Park, Geon; Jang, Sook Jin; Moon, Dae Soo

2012-01-01

This study was designed to compare two automated systems and one manual system for hepatitis B virus (HBV) nucleic acid extraction. The two automated systems were the MagNA Pure 96 system (Roche Applied Science, Manheim, Germany) and the Chemagic system (Chemagen, Baesweiler, Germany), and the manual system was the QIAamp system (Qiagen, Hilden, Germany). Sixty-eight samples that were within the detection range of the Cobas Ampliprep/Cobas TaqMan (CAP/CTM) platform (Roche Molecular Systems, Manheim, Germany) were selected. Extracted viral nucleic acids from the three systems were quantified using an AccuPower HBV Quantitative PCR kit (Bioneer, Daejon, Korea). The MagNA Pure 96 system and QIAamp system did not detect viral loads in one sample. The Chemagic system did not detect low viral loads in nine samples (range, 26-290 IU/mL by the CAP/CTM platform). Comparisons of the viral loads of the samples from the MagNA Pure 96 system, the Chemagic system, and the QIAamp system with those from the CAP/CTM platform yielded correlation coefficients of 0.977, 0.914, and 0.967, respectively. Comparisons of the MagNA Pure 96 system and the Chemagic system with the QIAamp system yielded correlation coefficients of 0.987 and 0.939, respectively. The MagNA Pure 96 system demonstrated better performance than the Chemagic system for HBV nucleic acid extraction. The MagNA Pure 96 system demonstrated comparable performance with the QIAamp system.

Study on the decomposition mechanism of alkyl carbonate on lithium metal by pyrolysis-gas chromatography-mass spectroscopy

NASA Astrophysics Data System (ADS)

Mogi, Ryo; Inaba, Minoru; Iriyama, Yasutoshi; Abe, Takeshi; Ogumi, Zempachi

The surface films formed on deposited lithium in electrolyte solutions based on ethylene carbonate (EC), diethyl carbonate (DEC), and dimethyl carbonate (DMC) were analyzed by pyrolysis-gas chromatography-mass spectroscopy (Py-GC-MS). In 1 M LiClO 4/EC, the main component of the surface film was easily hydrolyzed to give ethylene glycol after exposure to air, and hence was considered to have a chemical structure of ROCH 2CH 2OR', of which OR and OR' are OLi or OCO 2Li. Ethylene oxide, acetaldehyde, and 1,4-dioxane were detected in decomposition products, and they were considered to have been formed by pyrolysis of ROCH 2CH 2OR' in the pyrolyzer. The presence of ethanol in decomposition products confirmed that ring cleavage at the CH 2O bonds of EC occurs by one electron reduction. In addition, the presence of methanol implied the cleavage of the CC bond of EC upon reduction. From the surface films formed in 1 M LiClO 4/DEC and /DMC, ethanol and methanol, respectively, were detected, which suggested that corresponding lithium alkoxides and/or lithium alkyl carbonates were the main components. In 1 M LiClO 4/EC+DEC (1:1), EC dominantly decomposed to form the surface film. The surface film formed in 1 M LiPF 6/EC+DEC (1:1) contained a much smaller amount of organic compounds.

Improving clinical laboratory efficiency: a time-motion evaluation of the Abbott m2000 RealTime and Roche COBAS AmpliPrep/COBAS TaqMan PCR systems for the simultaneous quantitation of HIV-1 RNA and HCV RNA.

PubMed

Amendola, Alessandra; Coen, Sabrina; Belladonna, Stefano; Pulvirenti, F Renato; Clemens, John M; Capobianchi, M Rosaria

2011-08-01

Diagnostic laboratories need automation that facilitates efficient processing and workflow management to meet today's challenges for expanding services and reducing cost, yet maintaining the highest levels of quality. Processing efficiency of two commercially available automated systems for quantifying HIV-1 and HCV RNA, Abbott m2000 system and Roche COBAS Ampliprep/COBAS TaqMan 96 (docked) systems (CAP/CTM), was evaluated in a mid/high throughput workflow laboratory using a representative daily workload of 24 HCV and 72 HIV samples. Three test scenarios were evaluated: A) one run with four batches on the CAP/CTM system, B) two runs on the Abbott m2000 and C) one run using the Abbott m2000 maxCycle feature (maxCycle) for co-processing these assays. Cycle times for processing, throughput and hands-on time were evaluated. Overall processing cycle time was 10.3, 9.1 and 7.6 h for Scenarios A), B) and C), respectively. Total hands-on time for each scenario was, in order, 100.0 (A), 90.3 (B) and 61.4 min (C). The interface of an automated analyzer to the laboratory workflow, notably system set up for samples and reagents and clean up functions, are as important as the automation capability of the analyzer for the overall impact to processing efficiency and operator hands-on time.

VizieR Online Data Catalog: Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2003)

NASA Astrophysics Data System (ADS)

Ritter, H.; Kolb, U.

2003-08-01

Cataclysmic Binaries are semi-detached binaries consisting of a white dwarf or a white dwarf precursor primary and a low-mass secondary which is filling its critical Roche lobe. The secondary is not necessarily unevolved, it may even be a highly evolved star as for example in the case of the AM CVn-type stars. Low-Mass X-Ray Binaries are semi-detached binaries consisting of either a neutron star or a black hole primary, and a low-mass secondary which is filling its critical Roche lobe. Related Objects are detached binaries consisting of either a white dwarf or a white dwarf precursor primary and of a low-mass secondary. The secondary may also be a highly evolved star. The catalogue lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components and other characteristic properties of 501 cataclysmic binaries, 74 low-mass X-ray binaries and 114 related objects with known or suspected orbital periods together with a comprehensive selection of the relevant recent literature. In addition the catalogue contains a list of references to published finding charts for 651 of the 689 objects. A cross-reference list of alias object designations concludes the catalogue. Literature published before 30 June 2003 has, as far as possible, been taken into account. This catalogue supersedes the 5th edition (catalogue ) and the updated lists by Ritter and Kolb (1995; catalogue ) (1998; catalogue ). (10 data files).

Evaluation of Cobas Integra 800 under simulated routine conditions in six laboratories.

PubMed

Redondo, Francisco L; Bermudez, Pilar; Cocco, Claudio; Colella, Francesca; Graziani, Maria Stella; Fiehn, Walter; Hierla, Thomas; Lemoël, Gisèle; Belliard, AnneMarie; Manene, Dieudonne; Meziani, Mourad; Liebel, Maryann; McQueen, Matthew J; Stockmann, Wolfgang

2003-03-01

The new selective access analyser Cobas Integra 800 from Roche Diagnostics was evaluated in an international multicentre study at six sites. Routine simulation experiments showed good performance and full functionality of the instrument and provocation of anomalous situations generated no problems. The new features on Cobas Integra 800, namely clot detection and dispensing control, worked according to specifications. The imprecision of Cobas Integra 800 fulfilled the proposed quality specifications regarding imprecision of analytical systems for clinical chemistry with few exceptions. Claims for linearity, drift, and carry-over were all within the defined specifications, except urea linearity. Interference exists in some cases, as could be expected due to the chemistries applied. Accuracy met the proposed quality specifications, except in some special cases. Method comparisons with Cobas Integra 700 showed good agreement; comparisons with other analysis systems yielded in several cases explicable deviations. Practicability of Cobas Integra 800 met or exceeded the requirements for more than 95% of all attributes rated. The strong points of the new analysis system were reagent handling, long stability of calibration curves, high number of tests on board, compatibility of the sample carrier to other Roche systems, and the sample integrity check for more reliable analytical results. The improvement of the workflow offered by the 5-position rack and STAT handling like on Cobas Integra 800 makes the instrument attractive for further consolidation in the medium-sized laboratory, for dedicated use of special analytes, and/or as back-up in the large routine laboratory.

Evaluation of the Abbott RealTime HCV assay for quantitative detection of hepatitis C virus RNA.

PubMed

Michelin, Birgit D A; Muller, Zsofia; Stelzl, Evelyn; Marth, Egon; Kessler, Harald H

2007-02-01

The Abbott RealTime HCV assay for quantitative detection of HCV RNA has recently been introduced. In this study, the performance of the Abbott RealTime HCV assay was evaluated and compared to the COBAS AmpliPrep/COBAS TaqMan HCV test. Accuracy, linearity, interassay and intra-assay variations were determined, and a total of 243 routine clinical samples were investigated. When accuracy of the new assay was tested, the majority of results were found to be within +/-0.5 log(10) unit of the results obtained by reference laboratories. Determination of linearity resulted in a quasilinear curve up to 1.0 x 10(6)IU/ml. The interassay variation ranged from 15% to 32%, and the intra-assay variation ranged from 5% to 8%. When clinical samples were tested by the Abbott RealTime HCV assay and the results were compared with those obtained by the COBAS AmpliPrep/COBAS TaqMan HCV test, the results for 93% of all samples with positive results by both tests were found to be within +/-1.0 log(10) unit. The viral loads for all patients measured by the Abbott and Roche assays showed a high correlation (R(2)=0.93); quantitative results obtained by the Abbott assay were found to be lower than those obtained by the Roche assay. The Abbott RealTime HCV assay proved to be suitable for use in the routine diagnostic laboratory. The time to results was similar for both of the assays.

The Prevalence of Human Papilloma Virus (HPV) in Women using Liquid Base Pap Smear in Rasht, Northern of Iran.

PubMed

Mehran, Seyed Mohamad Mohseni; Ghanaei, Mandana Mansour; Mojtehadi, Ali

2015-07-01

HPV is one of the most common sexually transmitted infections. However, little is known about its prevalence in the female population in Rasht, Northern of Iran. The aim of this study was to find the incidences of HPV viruses in high-risk women in Rasht by wet Pap smear from 2010 to 2015. This cross-sectional study investigated HPV prevalence and its genotype distribution among 103 apparently healthy and non- healthy women with abnormal cells in pap exam. DNA samples were extracted by boiling and phenol - chloroform methods, then used as template for amplifying of specific fragment of HPV genome by PCR using GP5+ / GP6+ primers. PCR products were electrophoresed in 1.5% agarose gel (Roche, Germany) containing Sybrsafe. DNA ladder (Roche Co, Germany) was used to detect the molecular weights of observed bands under UV lamp. Overall, 4/98 women (4.08%) with normal cells and 1/5 women (20%) with abnormal cells were positive for at least one of the high risk HPV types in wet Pap smear. The most HPV infection was found in 26 to 39-year-old individuals. We evidenced a moderate prevalence of HPV infection but needs to be given more attention because in apparently healthy women also, HPV infection was observed. Health officials should conduct the study and wider screening of this infection occurring in this province. Screening for this infection must be recommended in this region.

Robotic Enrichment Processing of Roche 454 Titanium Emlusion PCR at the DOE Joint Genome Institute

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamilton, Matthew; Wilson, Steven; Bauer, Diane

2010-05-28

Enrichment of emulsion PCR product is the most laborious and pipette-intensive step in the 454 Titanium process, posing the biggest obstacle for production-oriented scale up. The Joint Genome Institute has developed a pair of custom-made robots based on the Microlab Star liquid handling deck manufactured by Hamilton to mediate the complexity and ergonomic demands of the 454 enrichment process. The robot includes a custom built centrifuge, magnetic deck positions, as well as heating and cooling elements. At present processing eight emulsion cup samples in a single 2.5 hour run, these robots are capable of processing up to 24 emulsion cupmore » samples. Sample emulsions are broken using the standard 454 breaking process and transferred from a pair of 50ml conical tubes to a single 2ml tube and loaded on the robot. The robot performs the enrichment protocol and produces beads in 2ml tubes ready for counting. The robot follows the Roche 454 enrichment protocol with slight exceptions to the manner in which it resuspends beads via pipette mixing rather than vortexing and a set number of null bead removal washes. The robotic process is broken down in similar discrete steps: First Melt and Neutralization, Enrichment Primer Annealing, Enrichment Bead Incubation, Null Bead Removal, Second Melt and Neutralization and Sequencing Primer Annealing. Data indicating our improvements in enrichment efficiency and total number of bases per run will also be shown.« less

Evaluation of the Ortho-Clinical Diagnostics Vitros ECi Anti-HCV test: comparison with three other methods.

PubMed

Watterson, Jeannette M; Stallcup, Paulina; Escamilla, David; Chernay, Patrick; Reyes, Alfred; Trevino, Sylvia C

2007-01-01

After observing a high incidence of low positive hepatitis C virus (HCV) antibody screens by the Ortho-Clinical Vitros ECi test (Orthoclinical Diagnostics, Raritan, NJ), we compared results against those obtained using another chemiluminescent analyzer, as well as two U.S. Food and Drug Administration (FDA)-approved confirmatory methodologies. To ascertain the true anti-HCV status of samples deemed low-positive by the Ortho-Clinical Vitros ECi test, we tested samples using the ADVIA Centaur HCV screen test (Siemens Medical Solutions Diagnostics), the Chiron recombinant immunoblot assay (RIBA) test (Chiron Corp., Emeryville, CA), and the Roche COBAS Amplicor HCV qualitative test (Roche Diagnostics, Indianapolis, IN) in a series of studies. Of 94 specimens positive by Vitros ECi, 19% were observed to be negative by Centaur. A separate study of 91 samples with signal-to-cutoff (s/co) values less than 8.0 showed that all but one was negative for HCV ribonucleic acid (RNA). In comparison with RIBA, 100% (77) samples positive by the Vitros ECi test with s/co values less than 12.0 were negative or indeterminate by RIBA. A final study comparing all four methods side-by-side showed 63% disagreement by Centaur for Vitros ECi low-positive samples, 75% disagreement by RIBA, and 97% disagreement by polymerase chain reaction (PCR). In conclusion, the Ortho-Clinical Vitros ECi Anti-HCV test yields a high rate of false-positive results in the low s/co range in our patient population. (c) 2007 Wiley-Liss, Inc.

FDA approval summary: vemurafenib for treatment of unresectable or metastatic melanoma with the BRAFV600E mutation.

PubMed

Kim, Geoffrey; McKee, Amy E; Ning, Yang-Min; Hazarika, Maitreyee; Theoret, Marc; Johnson, John R; Xu, Qiang Casey; Tang, Shenghui; Sridhara, Rajeshwari; Jiang, Xiaoping; He, Kun; Roscoe, Donna; McGuinn, W David; Helms, Whitney S; Russell, Anne Marie; Miksinski, Sarah Pope; Zirkelbach, Jeanne Fourie; Earp, Justin; Liu, Qi; Ibrahim, Amna; Justice, Robert; Pazdur, Richard

2014-10-01

On August 17, 2011, the U.S. Food and Drug Administration (FDA) approved vemurafenib tablets (Zelboraf, Hoffmann-LaRoche Inc.) for the treatment of patients with unresectable or metastatic melanoma with the BRAF(V600E) mutation as detected by an FDA-approved test. The cobas 4800 BRAF V600 Mutation Test (Roche Molecular Systems, Inc.) was approved concurrently. An international, multicenter, randomized, open-label trial in 675 previously untreated patients with BRAF(V600E) mutation-positive unresectable or metastatic melanoma allocated 337 patients to receive vemurafenib, 960 mg orally twice daily, and 338 patients to receive dacarbazine, 1,000 mg/m(2) intravenously every 3 weeks. Overall survival was significantly improved in patients receiving vemurafenib [HR, 0.44; 95% confidence interval (CI), 0.33-0.59; P < 0.0001]. Progression-free survival was also significantly improved in patients receiving vemurafenib (HR, 0.26; 95% CI, 0.20-0.33; P < 0.0001). Overall response rates were 48.4% and 5.5% in the vemurafenib and dacarbazine arms, respectively. The most common adverse reactions (≥30%) in patients treated with vemurafenib were arthralgia, rash, alopecia, fatigue, photosensitivity reaction, and nausea. Cutaneous squamous cell carcinomas or keratoacanthomas were detected in approximately 24% of patients treated with vemurafenib. Other adverse reactions included hypersensitivity, Stevens-Johnson syndrome, toxic epidermal necrolysis, uveitis, QT prolongation, and liver enzyme laboratory abnormalities. ©2014 American Association for Cancer Research.

Models for various aspects of dwarf novae and nova-like stars

NASA Technical Reports Server (NTRS)

Ladous, Constanze

1993-01-01

The first attempts to explain the nature of dwarf novae were based on the assumption of single-star phenomena, in which emission lines were assumed to be caused by circumstellar gas shells. The outburst behavior was tentatively ascribed to the kind of (also not understood) mechanism leading to nova outbursts. The realization that some, and possibly all, dwarf novae and nova-like stars (and novae) are binaries eventually led to models which bore more and more similarities to the modern interpretation on the basis of the Roche model. Not all cataclysmic variables are known binaries. In fact, with respect to the entire number of known objects, the proven binaries are still the minority, but all the brightest variables are in fact known to binaries. Not a single system is known which exhibits the usual characteristics of a cataclysmic variable and at the same time can be declared with certainty to be a single star. Two systems are known, the dwarf nova EY Cyg and the recurrent nova V1017 Sgr, in which, in spite of intensive search, no radial velocity variations have been found; but they still exhibit composite spectra consisting of a bright continuum, an emission spectrum, and a cool absorption spectrum. If the Roche model is correct, it is to be expected that a small percentage of objects is viewed pole-on, so orbital motions do not make themselves felt as Doppler shifts of spectral lines. So even these two systems support the hypothesis that all cataclysmic variables (with the possible exception of symbiotic stars) are binaries. In cataclysmic variables, it seems that the brightness changes observed in dwarf novae and nova-like stars in the optical and the UV are due directly to changes in the accretion disks. The study and understanding of accretion disks in these systems can bear potentially valuable consequences for many other fields in astronomy. The observed spectra of dwarf novae and nova-like stars comprise a fairly large range: pure emission spectra, pure absorption spectra, a mixture of both, asymmetric line profiles, very different slopes of the continuous flux distribution -- and one single system may exhibit all of these features at different times. Agreement and disagreement between computed and observed spectra should show whether or not the Roche model is applicable and where it probably will have to be modified and improved. Except for their outburst behavior and its immediate consequences, novae, dwarf novae, and nova-like stars cannot be physically distinguished from each other.

Service impact of a change in HIV-1 viral load quantification assay.

PubMed

Tipple, Craig; Oomeer, Soonita; Dosekun, Olamide; Mackie, Nicola

2014-01-01

Due to discontinuation of the Siemens Versant HIV-1 RNA (bDNA) assay in the UK, our laboratory switched to the Roche Cobas Ampliprep/Taqman HIV-1 viral load (VL) assay (Roche) in April 2013. This assay has a lower cut-off of 20 RNA copies/mL (compared with <50 for the Siemens assay). Our laboratory demonstrated previously that a significant proportion (18%) of patients undetectable using bDNA HIV-1 RNA quantification exhibited low level viraemia (LLV) using the new assay. Local guidelines recommend that patients stable on therapy receive twice-yearly VLs. We evaluated the impact of the introduction of the new assay on our clinical service. A retrospective cohort analysis of treated patients with stable undetectable VL by bDNA (<50 copies/mL) followed by ≥ one low-level (<400 copies/mL) VL with the Roche assay. Demographic data were collected in addition to frequency of VL testing and genotypic resistance assays. Referrals to virtual clinic (VC) were recorded. Patients were identified using laboratory data and information collected from electronic patient records. RESULTS were analyzed with SPSS v18. One hundred and ninety patients were included. 79.5% male; 60.6% homosexual; mean age of 46 years. Duration on stable treatment was 46.35 (std. dev. 38.15) months. Current treatment regimens were 43.3% PI-based; 43.3% NNRTI-based and 13.7% other. Patients were stratified into VL 20-49 copies/mL (n=109); VL 50-199 copies/mL (n=71) and VL 200-399 copies/mL (n=10). In total, there were 471 VLs measured of which 274 were additional as a result of the assay switch. This resulted in six HIV-1 genotype requests and 16 VC discussions (Table 1). Longer duration on HAART was associated with reduced frequency of VL testing. The relative risk of ongoing detectability according to drug class are: PI 1.62 (95% CI 1.18-2.21); NNRTI 0.507 (95% CI 0.30-0.85) and other 1.09 (95% CI 0.48-2.43). Changes in assay can result in difficulties in interpretation of patient results. The assay switch in our service had significant impact on patient and staff time and cost with an increase in patient recalls; increased frequency of VL measurement, genotypes and discussions in VC. Choice of assay is paramount to running an efficient and cost-effective clinical service.

Topography of the Flattest Surface on Earth: using ICESAT, GPS, and MISR to Measure Salt Surface Topography on Salar de Uyuni, Bolivia

NASA Technical Reports Server (NTRS)

Comstock, Robert L.; Bills, Bruce G.

2004-01-01

Salt flats are aptly named: they are composed largely of salt, and are maintained as nearly equipotential surfaces via frequent flooding. The salar de Uyuni, on the Altiplano in southwestern Bolivia, is the largest salt flat on Earth, with an area of 9,800 sq km. Except for a few bedrock islands, it has less than 40 cm of relief. The upper-most salt unit averages 5 m thick and contains 50 cu km of nearly pure halite. It includes most of the salt that was in solution in paleolake Minchin, which attained a maximum area of 60,000 sq km and a maximum depth of 150 m, roughly 15 kyr ago. Despite approx. 10 m of differential isostatic rebound since deposition, the salar surface has been actively maintained as an extraordinarily flat and smooth surface by annual flooding during the rainy season. We have used the strong optical absorption properties of water in the visible band to map spatial variations in water depth during a time when the salar was flooded. As water depth increases, the initially pure white surface appears both darker and bluer. We utilized MISR images taken during the interval from April to November 2001. The red and infra-red bands (672 and 867 nm wavelength) were most useful since the water depth is small and the absorption at those wavelengths is quite strong. Nadir pointed MISR images have 275 m spatial resolution. To aid in our evaluation of water depth variations over the saiar surface, we utilized two sources of direct topographic measurements: several ICESAT altimetry tracks cross the area, and a 40x50 km GPS grid was surveyed to calibrate ICESAT. A difficulty in using these data types is that both give salt surface elevations relative to the ellipsoid, whereas the water surface will, in the absence of wind or tidal disturbances, follow an equipotential surface. Geoid height is not known to the required accuracy of a few cm in the central Andes. As a result, before comparing optical absorption from MISR to salt surface topography from GPS or ICESAT, we removed the longest wavelengths from both.

Topography of the Moon from the Clementine Lidar

NASA Technical Reports Server (NTRS)

Smith, David E.; Zuber, Maria T.; Neumann, Gregory A.; Lemoine, Frank G.

1997-01-01

Range measurements from the lidar instrument carried aboard the Clementine spacecraft have been used to produce an accurate global topographic model of the Moon. This paper discusses the function of the lidar; the acquisition, processing, and filtering of observations to produce a global topographic model; and the determination of parameters that define the fundamental shape of the Moon. Our topographic model: a 72nd degree and order spherical harmonic expansion of lunar radii, is designated Goddard Lunar Topography Model 2 (GLTM 2). This topographic field has an absolute vertical accuracy of approximately 100 m and a spatial resolution of 2.5 deg. The field shows that the Moon can be described as a sphere with maximum positive and negative deviations of approx. 8 km, both occurring on the farside, in the areas of the Korolev and South Pole-Aitken (S.P.-Aitken) basins. The amplitude spectrum of the topography shows more power at longer wavelengths as compared to previous models, owing to more complete sampling of the surface, particularly the farside. A comparison of elevations derived from the Clementine lidar to control point elevations from the Apollo laser altimeters indicates that measured relative topographic heights generally agree to within approx. 200 in over the maria. While the major axis of the lunar gravity field is aligned in the Earth-Moon direction, the major axis of topography is displaced from this line by approximately 10 deg to the cast and intersects the farside 24 deg north of the equator. The magnitude of impact basin topography is greater than the lunar flattening (approx. 2 km) and equatorial ellipticity (approx. 800 m), which imposes a significant challenge to interpreting the lunar figure. The floors of mare basins are shown to lie close to an equipotential surface, while the floors of unflooded large basins, except for S.P.-Aitken, lie above this equipotential. The radii of basin floors are thus consistent with a hydrostatic mechanism for the absence of significant farside maria except for S.P.-Aitken, whose depth and lack of mare require significant internal compositional and/or thermal heterogeneity. A macroscale surface roughness map shows that roughness at length scales of 10(exp 1) - 10(exp 2) km correlates with elevation and surface age.

Design and analysis of a high power moderate band radiator using a switched oscillator

NASA Astrophysics Data System (ADS)

Armanious, Miena Magdi Hakeem

Quarter-wave switched oscillators (SWOs) are an important technology for the generation of high-power, moderate bandwidth (mesoband) wave forms. The use of SWOs in high power microwave sources has been discussed for the past 10 years [1--6], but a detailed discussion of the design of this type of oscillators for particular waveforms has been lacking. In this dissertation I develop a design methodology for a realization of SWOs, also known as MATRIX oscillators in the scientific community. A key element in the design of SWOs is the self-breakdown switch, which is created by a large electric field. In order for the switch to close as expected from the design, it is essential to manage the electrostatic field distribution inside the oscillator during the charging time. This enforces geometric constraints on the shape of the conductors inside MATRIX. At the same time, the electrodynamic operation of MATRIX is dependent on the geometry of the structure. In order to generate a geometry that satisfies both the electrostatic and electrodynamic constraints, a new approach is developed to generate this geometry using the 2-D static solution of the Laplace equation, subject to a particular set of boundary conditions. These boundary conditions are manipulated to generate equipotential lines with specific dimensions that satisfy the electrodynamic constraints. Meanwhile, these equipotential lines naturally support an electrostatic field distribution that meets the requirements for the switch operation. To study the electrodynamic aspects of MATRIX, three different (but interrelated) numerical models are built. Depending on the assumptions made in each model, different information about the electrodynamic properties of the designed SWO are obtained. In addition, the agreement and consistency between the different models, validate and give confidence in the calculated results. Another important aspect of the design process is understanding the relationship between the geometric parameters of MATRIX and the output waveforms. Using the numerical models, the relationship between the dimensions of MATRIX and its calculated resonant parameters are studied. For a given set of geometric constraints, this provides more flexibility to the output specifications. Finally, I present a comprehensive design methodology that generates the geometry of a MATRIX system from the desired specification then calculates the radiated waveform.

Complete genome sequence of Clostridium pasteurianum NRRL B-598, a non-type strain producing butanol.

PubMed

Sedlar, Karel; Kolek, Jan; Skutkova, Helena; Branska, Barbora; Provaznik, Ivo; Patakova, Petra

2015-11-20

The strain Clostridium pasteurianum NRRL B-598 is non-type, oxygen tolerant, spore-forming, mesophilic and heterofermentative strain with high hydrogen production and ability of acetone-butanol fermentation (ethanol production being negligible). Here, we present the annotated complete genome sequence of this bacterium, replacing the previous draft genome assembly. The genome consisting of a single circular 6,186,879 bp chromosome with no plasmid was determined using PacBio RSII and Roche 454 sequencing. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of aniracetam on delayed matching-to-sample performance of monkeys and pigeons.

PubMed

Pontecorvo, M J; Evans, H L

1985-05-01

A 3-choice, variable-delay, matching-to-sample procedure was used to evaluate drugs in both pigeons and monkeys while tested under nearly-identical conditions. Aniracetam (Roche 13-5057) improved accuracy of matching at all retention intervals following oral administration (12.5, 25 and 50 mg/kg) to macaque monkeys, with a maximal effect at 25 mg/kg. Aniracetam also antagonized scopolamine-induced impairment of the monkey's performance. Intramuscular administration of these same doses of aniracetam produced a similar, but not significant trend toward improved matching accuracy in pigeons.

Doublet craters and the tidal disruption of binary asteroids

NASA Technical Reports Server (NTRS)

Melosh, H. J.; Stansberry, J. A.

1991-01-01

An evaluation is conducted of the possibility that the tidal disruption of a population of contact binary asteroids can account for terrestrial-impact 'doublet' craters. Detailed orbital integrations indicate that while such asteroids are often disrupted by tidal forces outside the Roche limit, the magnitude of the resulting separations is too small to account for the observed doublet craters. It is hypothesized that an initial population of km-scale earth-crossing objects encompassing 10-20 percent binaries must be responsible for doublet impacts, as may be verified by future observations of earth-approaching asteroids.

Performance of the Abbott RealTime HIV-1 Viral Load Assay Is Not Impacted by Integrase Inhibitor Resistance-Associated Mutations▿

PubMed Central

Young, Thomas P.; Cloherty, Gavin; Fransen, Signe; Napolitano, Laura; Swanson, Priscilla; Herman, Christine; Parkin, Neil T.; Hackett, John

2011-01-01

The Abbott RealTime HIV-1 viral load assay uses primers and probes targeted to integrase, which is also the target of integrase inhibitors such as raltegravir. Viral loads of 42 raltegravir-susceptible and 40 raltegravir-resistant specimens were determined using RealTime HIV-1 and Roche Monitor (v1.5). The differences in viral load measurements between assays were comparable in the two groups, demonstrating that the RealTime HIV-1 assay can tolerate raltegravir-selected mutations. PMID:21289145

The mass of the black hole in the X-ray binary LMC X-1

NASA Astrophysics Data System (ADS)

Abubekerov, M. K.; Antokhina, E. A.; Gostev, N. Yu.; Cherepashchuk, A. M.; Shimansky, V. V.

2016-12-01

A dynamical estimate of the mass of the black hole in the LMC X-1 binary system is obtained in the framework of a Roche model for the optical star, based on fitting of the He I 4471 Å and He II 4200 Å absorption lines assuming LTE. The mass of the black hole derived from the radial-velocity curve for the He II 4200 Å line is m x = 10.55 M ⊙, close to the value found earlier based on a model with two point bodies [1].

CMV information: print, online, phone, video.

PubMed

1996-10-04

There are a number of treatment options available for cytomegalovirus (CMV) and approved preventive treatments for persons at high risk. Partnership in Vision has published a CMV Retinitis Report. A one-hour continuing medication education course entitled CMV Prophylaxis and Intraocular Therapy is available on the World Wide Web. The National Association of People with AIDS (NAPWA) has extended its CMV information hotline. Cidofovir is a new drug approved for marketing for CMV treatment. It is infused only once every two weeks. CMV videotapes are available from Hoffman-La Roche.

MODULAR ANALYTICS: A New Approach to Automation in the Clinical Laboratory.

PubMed

Horowitz, Gary L; Zaman, Zahur; Blanckaert, Norbert J C; Chan, Daniel W; Dubois, Jeffrey A; Golaz, Olivier; Mensi, Noury; Keller, Franz; Stolz, Herbert; Klingler, Karl; Marocchi, Alessandro; Prencipe, Lorenzo; McLawhon, Ronald W; Nilsen, Olaug L; Oellerich, Michael; Luthe, Hilmar; Orsonneau, Jean-Luc; Richeux, Gérard; Recio, Fernando; Roldan, Esther; Rymo, Lars; Wicktorsson, Anne-Charlotte; Welch, Shirley L; Wieland, Heinrich; Grawitz, Andrea Busse; Mitsumaki, Hiroshi; McGovern, Margaret; Ng, Katherine; Stockmann, Wolfgang

2005-01-01

MODULAR ANALYTICS (Roche Diagnostics) (MODULAR ANALYTICS, Elecsys and Cobas Integra are trademarks of a member of the Roche Group) represents a new approach to automation for the clinical chemistry laboratory. It consists of a control unit, a core unit with a bidirectional multitrack rack transportation system, and three distinct kinds of analytical modules: an ISE module, a P800 module (44 photometric tests, throughput of up to 800 tests/h), and a D2400 module (16 photometric tests, throughput up to 2400 tests/h). MODULAR ANALYTICS allows customised configurations for various laboratory workloads. The performance and practicability of MODULAR ANALYTICS were evaluated in an international multicentre study at 16 sites. Studies included precision, accuracy, analytical range, carry-over, and workflow assessment. More than 700 000 results were obtained during the course of the study. Median between-day CVs were typically less than 3% for clinical chemistries and less than 6% for homogeneous immunoassays. Median recoveries for nearly all standardised reference materials were within 5% of assigned values. Method comparisons versus current existing routine instrumentation were clinically acceptable in all cases. During the workflow studies, the work from three to four single workstations was transferred to MODULAR ANALYTICS, which offered over 100 possible methods, with reduction in sample splitting, handling errors, and turnaround time. Typical sample processing time on MODULAR ANALYTICS was less than 30 minutes, an improvement from the current laboratory systems. By combining multiple analytic units in flexible ways, MODULAR ANALYTICS met diverse laboratory needs and offered improvement in workflow over current laboratory situations. It increased overall efficiency while maintaining (or improving) quality.

Measurement Differences Between Two Immunoassay Systems for LH and FSH: A Comparison of Roche Cobas e601 vs. Abbott Architect i2000sr.

PubMed

Yin, Lianli; Tang, Yinghua; Chen, Xiang; Sun, Yifan

2018-03-01

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) regulate the growth and reproductive activity of gonadal tissue and determine the concentration of LH is essential for the prediction of ovulation. Collectively, FSH and LH are important measurements to ascertain the causes of infertility as well as diagnosing disorders such as polycystic ovary syndrome and pituitary and gonadal dysfunction. This study compares the correlation between LH and FSH measurements during examination with two different systems, Architect i2000sr (Abbott Laboratories; Lake Bluff, IL, USA) and Cobas e601 (Roche; Geneva, Switzerland), and assesses the differences between these systems. Serum analysis was performed for 95 patients using both the Cobas e601 and Architect i2000sr systems. The method used to compare the systems was Passing-Bablok regression analysis with a Bland-Altman agreement plot. Inter-rater agreement was analyzed using a concordance correlation coefficient. Architect i2000sr and Cobas e601 have strong correlations in their LH and FSH results. However, the Bland-Altman plot shows that LH and FSH measurements in Cobas e601 are about 1.31 times and 1.26 times higher than those in Architect i2000sr, respectively. Passing-Bablok regression analysis also shows significant proportional deviation between them. The difference between the test results for LH and FSH in Cobas e601 and Architect i2000sr indicate that the results from one system cannot be directly used to evaluate the other system.

Comparison of the Roche COBAS Amplicor Monitor, Roche COBAS Ampliprep/COBAS Taqman and Abbott RealTime Test assays for quantification of hepatitis C virus and HIV RNA.

PubMed

Wolff, Dietmar; Gerritzen, Andreas

2007-01-01

We have evaluated the performance of two newly developed automated real-time PCR assays, the COBAS Ampliprep/COBAS TaqMan (CAP/CTM) and the Abbott RealTime tests, in the quantification of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) RNA. The widely used semi-automated COBAS Amplicor Monitor (CAM) assay served as the reference test. Several specimens were analyzed, including 102 plasma samples from HCV patients and 109 from HIV patients and 10 samples from negative donors, as well as Quality Control in Molecular Diagnostics (QCMD) and National Institute for Biological Standards and Controls (NIBSC) proficiency program panels. Good correlation was observed among the three assays, with correlation coefficients (R2) of 0.8 (CAM-CAP/CTM), 0.89 (CAM-RealTime) and 0.91 (CAP/CTM-RealTime) for HCV and 0.83 (CAM-RealTime), 0.85 (CAM-CAP/CTM) and 0.89 (CAP/CTM-RealTime) for HIV. The overall concordance for negative/positive results was 100% for HCV and 98% for HIV. All assays were equally able to quantify HCV genotypes 1, 3, 5 and HIV group M (subtypes A-H) and N from QCMD and NIBSC panels. In terms of workflow, the RealTime assay requires more hands-on-time than the CAP/CTM assay. The results indicate that real-time PCR assays can improve the efficiency of end-point PCR tests by better covering viral dynamic ranges and providing higher throughput and automation.

Prolactin levels in manganese-exposed male welders.

PubMed

Tutkun, Engin; Abuşoğlu, Sedat; Yılmaz, Hinç; Gündüzöz, Meşide; Gıynas, Nilgün; Bal, Ceylan Demir; Ünlü, Ali

2014-12-01

Early studies on manganese (Mn) exposure have demonstrated that this transition metal affects dopamine neurotransmission. Dopamine serves as a tonic inhibitor of prolactin release in the anterior hypophysis. Our aim was to determine the relation between serum prolactin levels and manganese-exposure. Whole blood was collected from 95 non-exposed control subjects and 179 manganese-exposed male welders. Whole blood manganese was analyzed by Inductively Coupled Plasma--Mass Spectrometer on Agilent 7700 (Agilent Technologies, USA). Serum prolactin levels (PRL), aspartate transaminase (AST), alanine transaminase (ALT), urea, creatinine, soduim (Na), potassium (K) were analyzed by immunological and spectrophotometric methods on Roche E170 Modular System (Roche Diagnostics, Mannheim, Germany). The mean ages for control and manganese-exposed group were 40.5 ± 7.8 and 39.5 ± 8.7, respectively (p = 0.258). The mean working period (years) for control and manganese-exposed group were 17.4 ± 9.8 and 18.2 ± 7.7 years, respectively (p = 0.581). Serum AST and potassium levels were significantly higher in control group than manganese-exposed group (p = 0.002 and p = 0.048, respectively) and body-mass index (BMI) was significantly lower in control group than manganese-exposed group (p = 0.033). There was a significantly positive correlation between whole blood manganese levels and serum prolactin (r = 0.860, p < 0.001). Serum ALT levels were positively correlated with serum AST, urea and sodium (r = 0.315, p < 0.001; r = 0.121, p = 0.046; r = 0.130, p = 0.031). Serum prolactin level is a diagnostic marker for determining the effect of manganese-exposure.

MODULAR ANALYTICS: A New Approach to Automation in the Clinical Laboratory

PubMed Central

Zaman, Zahur; Blanckaert, Norbert J. C.; Chan, Daniel W.; Dubois, Jeffrey A.; Golaz, Olivier; Mensi, Noury; Keller, Franz; Stolz, Herbert; Klingler, Karl; Marocchi, Alessandro; Prencipe, Lorenzo; McLawhon, Ronald W.; Nilsen, Olaug L.; Oellerich, Michael; Luthe, Hilmar; Orsonneau, Jean-Luc; Richeux, Gérard; Recio, Fernando; Roldan, Esther; Rymo, Lars; Wicktorsson, Anne-Charlotte; Welch, Shirley L.; Wieland, Heinrich; Grawitz, Andrea Busse; Mitsumaki, Hiroshi; McGovern, Margaret; Ng, Katherine; Stockmann, Wolfgang

2005-01-01

MODULAR ANALYTICS (Roche Diagnostics) (MODULAR ANALYTICS, Elecsys and Cobas Integra are trademarks of a member of the Roche Group) represents a new approach to automation for the clinical chemistry laboratory. It consists of a control unit, a core unit with a bidirectional multitrack rack transportation system, and three distinct kinds of analytical modules: an ISE module, a P800 module (44 photometric tests, throughput of up to 800 tests/h), and a D2400 module (16 photometric tests, throughput up to 2400 tests/h). MODULAR ANALYTICS allows customised configurations for various laboratory workloads. The performance and practicability of MODULAR ANALYTICS were evaluated in an international multicentre study at 16 sites. Studies included precision, accuracy, analytical range, carry-over, and workflow assessment. More than 700 000 results were obtained during the course of the study. Median between-day CVs were typically less than 3% for clinical chemistries and less than 6% for homogeneous immunoassays. Median recoveries for nearly all standardised reference materials were within 5% of assigned values. Method comparisons versus current existing routine instrumentation were clinically acceptable in all cases. During the workflow studies, the work from three to four single workstations was transferred to MODULAR ANALYTICS, which offered over 100 possible methods, with reduction in sample splitting, handling errors, and turnaround time. Typical sample processing time on MODULAR ANALYTICS was less than 30 minutes, an improvement from the current laboratory systems. By combining multiple analytic units in flexible ways, MODULAR ANALYTICS met diverse laboratory needs and offered improvement in workflow over current laboratory situations. It increased overall efficiency while maintaining (or improving) quality. PMID:18924721

Continuous Glucose Monitoring in Newborn Infants

PubMed Central

Thomas, Felicity; Signal, Mathew; Harris, Deborah L.; Weston, Philip J.; Harding, Jane E.; Shaw, Geoffrey M.

2014-01-01

Neonatal hypoglycemia is common and can cause serious brain injury. Continuous glucose monitoring (CGM) could improve hypoglycemia detection, while reducing blood glucose (BG) measurements. Calibration algorithms use BG measurements to convert sensor signals into CGM data. Thus, inaccuracies in calibration BG measurements directly affect CGM values and any metrics calculated from them. The aim was to quantify the effect of timing delays and calibration BG measurement errors on hypoglycemia metrics in newborn infants. Data from 155 babies were used. Two timing and 3 BG meter error models (Abbott Optium Xceed, Roche Accu-Chek Inform II, Nova Statstrip) were created using empirical data. Monte-Carlo methods were employed, and each simulation was run 1000 times. Each set of patient data in each simulation had randomly selected timing and/or measurement error added to BG measurements before CGM data were calibrated. The number of hypoglycemic events, duration of hypoglycemia, and hypoglycemic index were then calculated using the CGM data and compared to baseline values. Timing error alone had little effect on hypoglycemia metrics, but measurement error caused substantial variation. Abbott results underreported the number of hypoglycemic events by up to 8 and Roche overreported by up to 4 where the original number reported was 2. Nova results were closest to baseline. Similar trends were observed in the other hypoglycemia metrics. Errors in blood glucose concentration measurements used for calibration of CGM devices can have a clinically important impact on detection of hypoglycemia. If CGM devices are going to be used for assessing hypoglycemia it is important to understand of the impact of these errors on CGM data. PMID:24876618

Journalism as health education: media coverage of a nonbranded pharma web site.

PubMed

Mackert, Michael; Love, Brad; Holton, Avery E

2011-03-01

As healthcare consumers increasingly use the Internet as a source for health information, direct-to-consumer (DTC) prescription drug advertising online merits additional attention. The purpose of this research was to investigate media coverage of the joint marketing program linking the movie Happy Feet and the nonbranded disease education Web site FluFacts-a resource from Tamiflu flu treatment manufacturer Roche Laboratories Inc. Twenty-nine articles (n = 29) were found covering the Happy Feet-FluFacts marketing campaign. A coding guide was developed to assess elements of the articles, including those common in the sample and information that ideally would be included in these articles. Two coders independently coded the articles, achieving intercoder agreement of κ = 0.98 before resolving disagreements to arrive at a final dataset. The majority of articles reported that Roche operated FluFacts (51.7%) and mentioned the product Tamiflu (58.6%). Almost half (48.3%) reported FluFacts was an educational resource; yet, no articles mentioned other antiviral medications or nonmedical options for preventing the flu. Almost a quarter of the articles (24.1%) provided a call to action-telling readers to visit FluFacts or providing a link for them to do so. Findings suggest that journalists' coverage of this novel campaign-likely one of the goals of the campaign-helped spread the message of the Happy Feet-FluFacts relationship, often omitting other useful health information. Additional research is needed to better understand online DTC campaigns and how consumers react to these campaigns and resulting media coverage and to inform the policymakers' decisions regarding DTC advertising online.

STABILITY OF GAS CLOUDS IN GALACTIC NUCLEI: AN EXTENDED VIRIAL THEOREM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Xian; Cuadra, Jorge; Amaro-Seoane, Pau, E-mail: xchen@astro.puc.cl, E-mail: jcuadra@astro.puc.cl, E-mail: Pau.Amaro-Seoane@aei.mpg.de

2016-03-10

Cold gas entering the central 1–10{sup 2} pc of a galaxy fragments and condenses into clouds. The stability of the clouds determines whether they will be turned into stars or can be delivered to the central supermassive black hole (SMBH) to turn on an active galactic nucleus (AGN). The conventional criteria to assess the stability of these clouds, such as the Jeans criterion and Roche (or tidal) limit, are insufficient here, because they assume the dominance of self-gravity in binding a cloud, and neglect external agents, such as pressure and tidal forces, which are common in galactic nuclei. We formulatemore » a new scheme for judging this stability. We first revisit the conventional Virial theorem, taking into account an external pressure, to identify the correct range of masses that lead to stable clouds. We then extend the theorem to further include an external tidal field, which is equally crucial for the stability in the region of our interest—in dense star clusters, around SMBHs. We apply our extended Virial theorem to find new solutions to controversial problems, namely, the stability of the gas clumps in AGN tori, the circum-nuclear disk in the Galactic Center, and the central molecular zone of the Milky Way. The masses we derive for these structures are orders of magnitude smaller than the commonly used Virial masses (equivalent to the Jeans mass). Moreover, we prove that these clumps are stable, contrary to what one would naively deduce from the Roche (tidal) limit.« less

Resolution of an apparent hook effect in Roche partner DRI oxycodone immunoassay.

PubMed

Colón-Franco, Jessica M; Cox, Elbert T; Crosby, David B; Dawling, Sheila

2013-01-01

A presumed hook effect in the semiquantitative DRI Oxycodone immunoassay, OXY3S (Cobas Integra, Roche Diagnostics), was investigated in 14 urine samples with gas chromatography/mass spectrometry (GC-MS) >10,000 ng/mL but OXY3S <1,000 ng/mL. These samples included the index case, a false-negative OXY3S result with >75,000 ng/mL oxycodone + oxymorphone by GC-MS confirmation. Patient samples needed 2- to 16-fold dilution to obtain the correct OXY3S response. The OXY3S test did not hook at high-spiked concentrations of oxycodone, oxymorphone or oxymorphone-3β-d-glucuronide in drug-free urine. The OXY3S test parameters were replicated in a development channel on the Cobas using DRI Reagents (Microgenics, CA, USA) and were subsequently modified. Delayed sample addition or doubling of Reagent 1 (R1: antibody/substrate/co-factor) yielded maximal immunoassay response (>10,000 ng/mL) in 12 of 14 and 14 of 14 undiluted patient samples, respectively. Supplementation of R1 with substrate alone did not correctly recover oxycodone from any of the samples, while co-factor supplementation resulted a maximal OXY3S response in 13 of 14 samples. The remaining (index) sample could only be corrected by supplemental R1. The semiquantitative utility of the DRI Oxycodone assay is questionable. Although the precise cause of the under-recovery could not be determined, the modification presented permits reliable oxycodone determination at the high concentrations frequently seen in clinical urine samples.

Hemolysis indexes for biochemical tests and immunoassays on Roche analyzers: determination of allowable interference limits according to different calculation methods.

PubMed

Monneret, Denis; Mestari, Fouzi; Atlan, Gregory; Corlouer, Camille; Ramani, Zo; Jaffre, Jeremy; Dever, Sylvie; Fressart, Veronique; Alkouri, Rana; Lamari, Foudil; Devilliers, Catherine; Imbert-Bismut, Françoise; Bonnefont-Rousselot, Dominique

2015-04-01

To determine the hemolysis interference on biochemical tests and immunoassays performed on Roche Diagnostics analyzers, according to different maximum allowable limits. Heparinized plasma and serum pools, free of interferences, were overloaded by increasing amounts of a hemoglobin-titrated hemolysate. This interference was evaluated for 45 analytes using Modular(®) and Cobas(®) analyzers. For each parameter, the hemolysis index (HI) corresponding to the traditional ± 10% change of concentrations from baseline (± 10%Δ) was determined, as well as those corresponding to the analytical change limit (ACL), and to the reference change value (RCV). Then, the relative frequencies distribution (% RFD) of hemolyzed tests performed in a hospital laboratory over a 25-day period were established for each HI as allowable limit. Considering the ± 10%Δ, the analyte concentrations enhanced by hemolysis were: Lactate dehydrogenase (LDH), aspartate aminotransferase (AST), folate, potassium, creatine kinase, phosphorus, iron, alanine aminotransferase, lipase, magnesium and triglycerides, decreasingly. The analyte concentrations decreased by hemolysis were: Haptoglobin, high-sensitive troponin T and alkaline phosphatase. Over the 25-day period, the % RFD of tests impacted more than 10%Δ by hemolysis were < 7% for LDH; < 5% for AST, folates and iron; and < 1% for the other analytes. Considering the ACL, HI were lower, giving % RFD substantially increased for many analytes, whereas only four analytes remain sensitive to hemolysis when considering RCV. This study proposes new HI based on different allowable limits, and can therefore serve as a starting point for future harmonization of hemolysis interference evaluation needed in routine laboratory practice.

Developing Disease-Modifying Treatments in Alzheimer's Disease - A Perspective from Roche and Genentech.

PubMed

Doody, R

2017-01-01

Alzheimer's disease (AD) is a chronic neurodegenerative disease for which no preventative or disease-modifying treatments currently exist. Pathological hallmarks include amyloid plaques and neurofibrillary tangles composed of hyper-phosphorylated tau protein. Evidence suggests that both pathologies are self-propagating once established. However, the lag time between neuropathological changes in the brain and the onset of even subtle clinical symptomatology means that patients are often diagnosed late when pathology, and neurodegeneration secondary to these changes, may have been established for several years. Complex pathological pathways associated with susceptibility to AD and changes that occur downstream of the neuropathologic process further contribute to the challenging endeavour of developing novel disease-modifying therapy. Recognising this complexity, effective management of AD must include reliable screening and early diagnosis in combination with effective therapeutic management of the pathological processes. Roche and Genentech are committed to addressing these unmet needs through developing a comprehensive portfolio of diagnostics and novel therapies. Beginning with the most scientifically supported targets, this approach includes two targeted amyloid-β monoclonal antibody therapies, crenezumab and gantenerumab, and an anti-tau monoclonal antibody, RO7105705, as well as a robust biomarker platform to aid in the early identification of people at risk or in the early stages of AD. Identification and implementation of diagnostic tools will support the enrolment of patients into clinical trials; furthermore, these tools should also support evaluation of the clinical efficacy and safety profile of the novel therapeutic agents tested in these trials. This review discusses the therapeutic agents currently under clinical development.

Optimizing Anti-VEGF Treatment Outcomes for Patients with Neovascular Age-Related Macular Degeneration.

PubMed

Wykoff, Charles C; Clark, W Lloyd; Nielsen, Jared S; Brill, Joel V; Greene, Laurence S; Heggen, Cherilyn L

2018-02-01

The introduction of anti-vascular endothelial growth factor (anti-VEGF) drugs to ophthalmology has revolutionized the treatment of neovascular age-related macular degeneration (nAMD). Despite this significant progress, gaps and challenges persist in the diagnosis of nAMD, initiation of treatment, and management of frequent intravitreal injections. Thus, nAMD remains a leading cause of blindness in the United States. To present current knowledge, evidence, and expert perspectives on anti-VEGF therapies in nAMD to support managed care professionals and providers in decision making and collaborative strategies to overcome barriers to optimize anti-VEGF treatment outcomes among nAMD patients. Three anti-VEGF therapies currently form the mainstay of treatment for nAMD, including 2 therapies approved by the FDA for treatment of nAMD (aflibercept and ranibizumab) and 1 therapy approved by the FDA for oncology indications and used off-label for treatment of nAMD (bevacizumab). In clinical trials, each of the 3 agents maintained visual acuity (VA) in approximately 90% or more of nAMD patients over 2 years. However, in long-term and real-world settings, significant gaps and challenges in diagnosis, treatment, and management pose barriers to achieving optimal outcomes for patients with nAMD. Many considerations, including individual patient characteristics, on-label versus off-label treatment, repackaging, and financial considerations, add to the complexity of nAMD decision making and management. Many factors may contribute to additional challenges leading to suboptimal long-term outcomes among nAMD patients, such as delays in diagnosis and/or treatment approval and initiation, individual patient response to different anti-VEGF therapies, lapses in physician regimentation of anti-VEGF injection and monitoring, and inadequate patient adherence to treatment and monitoring. These latter factors highlight the considerable logistical, emotional, and financial burdens of long-term, frequent intravitreal injections and the vital importance of personalized approaches to anti-VEGF treatment decision making and management for patients with nAMD. To address these challenges and reduce the number of yearly injections, studies have examined alternative dosing regimens, including extended fixed intervals, as needed, and treat-and-extend strategies in specific nAMD patient populations. New clinical evidence and insights into expert clinical practice discussed in this article can support managed care professionals in the key role they play in addressing challenges in nAMD treatment and management and optimizing patient outcomes through appropriate management of anti-VEGF treatment. PRIME Education is an independent medical education company and has been an accredited provider of continuing education for 23 years. There is no fee for this activity as it is sponsored by PRIME through an educational grant from Regeneron. All authors contributed to the writing and reviewing of the article. Wykoff reports consultancies/research grants from Alcon Laboratories, Genentech/Roche, Clearside, and Iconic Therapeutics; consultancies/honoraria, research grants, and speaker fees from Allergan and Regeneron; research grants from Allegro, Apellis, Aura, NEI, NIH, Novartis, OHR Pharmaceuticals, Ophthotech, pSivida, Roche, Santen, SciFluor, Tyrogenex; and consultancies for Alimera Sciences, Alnylam Pharmaceuticals, Bayer, DORC, ONL Therapeutics, Thrombogenics, and Valeant. Clark reports advisory board work, consultancies, research grants, and speaker fees from Genentech/Roche and Regeneron and consultancy for Bayer. Brill reports consultancies for Aries Pharma, Avella, BaroNova, Braeburn Pharmaceuticals, Cardinal Health, Endogastric Solutions, GeneNews, Halt Medical, Lumendi, Medtronic, Monteris Medical, Natera, Phosphorus, Rebiotix, Seno Medical, UCB, Vermillion, Echosens, and HAP Innovations. Brill is a shareholder in EndoChoice, GeneNews, SonarMD, and SynerZ and reports advisory board work with Nestle Health Sciences, Indivior Pharmaceuticals, Eli Lilly, Blue Earth Diagnostics, Bayer, and AstraZeneca. Nielson reports advisory board work/consultancy and research grants for Genentech/Roche; advisory board work and research grants from Regeneron; and research grants from Alcon and Ophthotech.

Evolution of vaporizing pulsars

NASA Technical Reports Server (NTRS)

Mccormick, P.

1994-01-01

We construct evolutional scenarios for LMXB's using a simplified stellar model. We discuss the origin and evolution of short-period, low mass binary pulsars with evaporating companions. We suggest that these systems descend from low-mass X-ray binaries and that angular momentum loss mainly due to evaporative wind drives their evolution. We derive limits on the energy and angular momentum carried away by the wind based on the observed low eccentricity. In our model the companion remains near contact, and its quasiadiabatic expansion causes the binary to expand. Short-term oscillations of the orbital period may occur if the Roche-lobe overflow forms an evaporating disk.

Methodologies for Quantitative Systems Pharmacology (QSP) Models: Design and Estimation.

PubMed

Ribba, B; Grimm, H P; Agoram, B; Davies, M R; Gadkar, K; Niederer, S; van Riel, N; Timmis, J; van der Graaf, P H

2017-08-01

With the increased interest in the application of quantitative systems pharmacology (QSP) models within medicine research and development, there is an increasing need to formalize model development and verification aspects. In February 2016, a workshop was held at Roche Pharma Research and Early Development to focus discussions on two critical methodological aspects of QSP model development: optimal structural granularity and parameter estimation. We here report in a perspective article a summary of presentations and discussions. © 2017 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

Catalytic, Enantioselective Synthesis of Stilbene cis-Diamines: A Concise Preparation of (–)-Nutlin-3, a Potent p53/MDM2 Inhibitor

PubMed Central

Davis, Tyler A.

2012-01-01

The first highly diastereo- and enantioselective additions of aryl nitromethane pronucleophiles to aryl aldimines are described. Identification of an electron rich chiral Bis(Amidine) catalyst for this aza-Henry variant was key to this development, leading ultimately to differentially protected cis-stilbene diamines in two steps. This method then became the lynchpin for an enantioselective synthesis of (–)-Nutlin-3 (Hoffmann-LaRoche), a potent cis-imidazoline small molecule inhibitor of p53-MDM2 used extensively as a probe of cell biology and currently in drug development. PMID:22708054

SCARF: maximizing next-generation EST assemblies for evolutionary and population genomic analyses.

PubMed

Barker, Michael S; Dlugosch, Katrina M; Reddy, A Chaitanya C; Amyotte, Sarah N; Rieseberg, Loren H

2009-02-15

Scaffolded and Corrected Assembly of Roche 454 (SCARF) is a next-generation sequence assembly tool for evolutionary genomics that is designed especially for assembling 454 EST sequences against high-quality reference sequences from related species. The program was created to knit together 454 contigs that do not assemble during traditional de novo assembly, using a reference sequence library to orient the 454 sequences. SCARF is freely available at http://msbarker.com/software.htm, and is released under the open source GPLv3 license (http://www.opensource.org/licenses/gpl-3.0.html.

AK Sco: a tidally induced atmospheric dynamo in a pre-main sequence binary?

NASA Astrophysics Data System (ADS)

Gómez de Castro, A. I.

2009-02-01

AK Sco is a unique source: a 10-30 Myrs old pre-main sequence spectroscopic binary composed by two nearly equal F5 stars that at periastron are separated by barely eleven stellar radii so, the stellar magnetospheres fill the Roche lobe at periastron. The orbit is not yet circularized (e = 0.47) and very strong tides are expected. This makes of AK Sco, the ideal laboratory to study the effect of gravitational tides in the stellar magnetic field building up during pre-main sequence evolution. Evidence of this effect is reported in this contribution.

[Epidermic chalone receptors in psoriasis treated with retinoid:Ro 10-9359].

PubMed

Vignale, R A; Lasalvia, E; Espasandín, J; Borras, A

1983-01-01

The epidermic chalone receptor of skin with lesion and without lesion are studied on 20 patients with active psoriasis. The testlest were performed before and two month after oral treatment with RO 10-9359. Roche. The results show significant variation with an increased a the number of receptors after treatment. As these receptors are in the cell membrane, the authors consider that RO 10-9359 action in on the membrane and its surrounding, making in possible to the epithelial cell to begin its autoregulation, autocontrol and differentiation when the specific activity of the chalones become normal.

Proto-jet configurations in RADs orbiting a Kerr SMBH: symmetries and limiting surfaces

NASA Astrophysics Data System (ADS)

Pugliese, D.; Stuchlík, Z.

2018-05-01

Ringed accretion disks (RADs) are agglomerations of perfect-fluid tori orbiting around a single central attractor that could arise during complex matter inflows in active galactic nuclei. We focus our analysis to axi-symmetric accretion tori orbiting in the equatorial plane of a supermassive Kerr black hole; equilibrium configurations, possible instabilities, and evolutionary sequences of RADs were discussed in our previous works. In the present work we discuss special instabilities related to open equipotential surfaces governing the material funnels emerging at various regions of the RADs, being located between two or more individual toroidal configurations of the agglomerate. These open structures could be associated to proto-jets. Boundary limiting surfaces are highlighted, connecting the emergency of the jet-like instabilities with the black hole dimensionless spin. These instabilities are observationally significant for active galactic nuclei, being related to outflows of matter in jets emerging from more than one torus of RADs orbiting around supermassive black holes.

A porous flow model for the geometrical form of volcanoes - Critical comments

NASA Technical Reports Server (NTRS)

Wadge, G.; Francis, P.

1982-01-01

A critical evaluation is presented of the assumptions on which the mathematical model for the geometrical form of a volcano arising from the flow of magma in a porous medium of Lacey et al. (1981) is based. The lack of evidence for an equipotential surface or its equivalent in volcanoes prior to eruption is pointed out, and the preference of volcanic eruptions for low ground is attributed to the local stress field produced by topographic loading rather than a rising magma table. Other difficulties with the model involve the neglect of the surface flow of lava under gravity away from the vent, and the use of the Dupuit approximation for unconfined flow and the assumption of essentially horizontal magma flow. Comparisons of model predictions with the shapes of actual volcanoes reveal the model not to fit lava shield volcanoes, for which the cone represents the solidification of small lava flows, and to provide a poor fit to composite central volcanoes.

Spatial potential ripples of azimuthal surface modes in topological insulator Bi2Te3 nanowires

PubMed Central

Muñoz Rojo, Miguel; Zhang, Yingjie; Manzano, Cristina V.; Alvaro, Raquel; Gooth, Johannes; Salmeron, Miquel; Martin-Gonzalez, Marisol

2016-01-01

Topological insulators (TI) nanowires (NW) are an emerging class of structures, promising both novel quantum effects and potential applications in low-power electronics, thermoelectrics and spintronics. However, investigating the electronic states of TI NWs is complicated, due to their small lateral size, especially at room temperature. Here, we perform scanning probe based nanoscale imaging to resolve the local surface potential landscapes of Bi2Te3 nanowires (NWs) at 300 K. We found equipotential rings around the NWs perimeter that we attribute to azimuthal 1D modes. Along the NW axis, these modes are altered, forming potential ripples in the local density of states, due to intrinsic disturbances. Potential mapping of electrically biased NWs enabled us to accurately determine their conductivity which was found to increase with the decrease of NW diameter, consistent with surface dominated transport. Our results demonstrate that TI NWs can pave the way to both exotic quantum states and novel electronic devices. PMID:26751282

Spatiotemporal mapping of scalp potentials.

PubMed

Fender, D H; Santoro, T P

1977-11-01

Computerized analysis and display techniques are applied to the problem of identifying the origins of visually evoked scalped potentials (VESP's). A new stimulus for VESP work, white noise, is being incorporated in the solution of this problem. VESP's for white-noise stimulation exhibit time domain behavior similar to the classical response for flash stimuli but with certain significant differences. Contour mapping algorithms are used to display the time behavior of equipotential surfaces on the scalp during the VESP. The electrical and geometrical parameters of the head are modeled. Electrical fields closely matching those obtained experimentally are generated on the surface of the model head by optimally selecting the location and strength parameters of one or two dipole current sources contained within the model. Computer graphics are used to display as a movie the actual and model scalp potential field and the parameters of the dipole generators whithin the model head during the time course of the VESP. These techniques are currently used to study retinotopic mapping, fusion, and texture perception in the human.

Hyperthermia with implanted electrodes.

PubMed

Brezovich, I A; Young, J H

1981-01-01

A general solution is given for the steady state form of the heat conduction equation applied to a simple tumor model which is imagined as being heated by means of electrical currents flowing between metallic electrodes. The model assumes a homogeneous tumor with no bloodflow. The solution for the special case of constant temperature and potential at the surface of the heated volume is examined in detail. The solution shows that there exists, independent of the particular tumor and electrode geometry, a close relationship between the steady state temperature distribution and the electrical potential. Among the more important implications of this relationship are that equipotential surfaces within the heated volume are also isothermal surfaces and that no areas of excessive heat at or near any sharp edges or corners of the electrodes should develop, despite the high electric field intensity. Based on the theory, a procedure is outlined which might greatly facilitate the determination of temperature distributions in phantoms. Finally, the usefulness and the limitations of the theoretical models in clinical hyperthermia are discussed.

Optics of ion beams for the neutral beam injection system on HL-2A Tokamak.

PubMed

Zou, G Q; Lei, G J; Cao, J Y; Duan, X R

2012-07-01

The ion beam optics for the neutral beam injection system on HL-2A Tokomak is studied by two- dimensional numerical simulation program firstly, where the emitting surface is taken at 100 Debye lengths from the plasma electrode. The mathematical formulation, computation techniques are described. Typical ion orbits, equipotential contours, and emittance diagram are shown. For a fixed geometry electrode, the effect of plasma density, plasma potential and plasma electron temperature on ion beam optics is examined, and the calculation reliability is confirmed by experimental results. In order to improve ion beam optics, the application of a small pre-acceleration voltage (∼100 V) between the plasma electrode and the arc discharge anode is reasonable, and a lower plasma electron temperature is desired. The results allow optimization of the ion beam optics in the neutral beam injection system on HL-2A Tokomak and provide guidelines for designing future neutral beam injection system on HL-2M Tokomak.

Free-air and Bouguer gravity anomalies and the Martian crustal dichotomy

NASA Technical Reports Server (NTRS)

Frey, Herbert; Bills, Bruce G.; Kiefer, Walter S.; Nerem, R. Steven; Roark, James H.; Zuber, Maria T.

1993-01-01

Free-air and Bouguer gravity anomalies from a 50x50 field, derived from re-analysis of Viking Orbiter and Mariner 9 tracking data and using a 50x50 expansion of the current Mars topography and the GSFC degree 50 geoid as the equipotential reference surface, with the Martian crustal dichotomy are compared. The spherical harmonic topography used has zero mean elevation, and differs from the USGS maps by about 2 km. In this field the dichotomy boundary in eastern Mars lies mostly at -1 to -2 km elevation. Bouguer gravity anomalies are shown on a map of Noachian, Hesperian, and Amazonian age terrains, simplified from current geologic maps. The map is centered at 300 deg W to show the continuity of the dichotomy boundary. Contour interval is 100 mgals. Gravity and topography were compared along approximately 40 profiles oriented parallel to the dichotomy boundary topographic gradient, to determine how the geophysical character of the boundary changes along its length and what this implies for its origin and development.

Electrophysiological mapping of the accessory olfactory bulb of the rabbit (Oryctolagus cuniculus).

PubMed

van Groen, T; Ruardy, L; da Silva, F H

1986-07-01

Field potentials elicited by electrical stimulation of the vomeronasal nerve were measured in the accessory olfactory bulb of the rabbit. Maps were made of the distribution of surface field potentials and of the corresponding depth profiles. The surface maps followed closely the contours of the accessory olfactory bulb: at the frontal border the field potential tended to zero and at the center of the structure the field potential attained a maximum. Depth profiles of the field potentials through the accessory olfactory bulb presented a surface-negative wave and, in depth, a positive wave. The polarity reversal occurred at the deep part of the granule cell layer. The zero equipotential line followed closely the curvature of the granule cell layer. Current source density analysis of the depth profiles revealed a main sink at the external plexiform and granule cell layers. This indicates that the main activity in the accessory olfactory bulb is generated by the synapses between the mitral cells and the granule cells as is found in the main olfactory bulb.

Finite element simulations of electrostatic dopant potentials in thin semiconductor specimens for electron holography.

PubMed

Somodi, P K; Twitchett-Harrison, A C; Midgley, P A; Kardynał, B E; Barnes, C H W; Dunin-Borkowski, R E

2013-11-01

Two-dimensional finite element simulations of electrostatic dopant potentials in parallel-sided semiconductor specimens that contain p-n junctions are used to assess the effect of the electrical state of the surface of a thin specimen on projected potentials measured using off-axis electron holography in the transmission electron microscope. For a specimen that is constrained to have an equipotential surface, the simulations show that the step in the projected potential across a p-n junction is always lower than would be predicted from the properties of the bulk device, but is relatively insensitive to the value of the surface state energy, especially for thicker specimens and higher dopant concentrations. The depletion width measured from the projected potential, however, has a complicated dependence on specimen thickness. The results of the simulations are of broader interest for understanding the influence of surfaces and interfaces on electrostatic potentials in nanoscale semiconductor devices. © 2013 Elsevier B.V. All rights reserved.

Spatial potential ripples of azimuthal surface modes in topological insulator Bi2Te3 nanowires.

PubMed

Muñoz Rojo, Miguel; Zhang, Yingjie; Manzano, Cristina V; Alvaro, Raquel; Gooth, Johannes; Salmeron, Miquel; Martin-Gonzalez, Marisol

2016-01-11

Topological insulators (TI) nanowires (NW) are an emerging class of structures, promising both novel quantum effects and potential applications in low-power electronics, thermoelectrics and spintronics. However, investigating the electronic states of TI NWs is complicated, due to their small lateral size, especially at room temperature. Here, we perform scanning probe based nanoscale imaging to resolve the local surface potential landscapes of Bi2Te3 nanowires (NWs) at 300 K. We found equipotential rings around the NWs perimeter that we attribute to azimuthal 1D modes. Along the NW axis, these modes are altered, forming potential ripples in the local density of states, due to intrinsic disturbances. Potential mapping of electrically biased NWs enabled us to accurately determine their conductivity which was found to increase with the decrease of NW diameter, consistent with surface dominated transport. Our results demonstrate that TI NWs can pave the way to both exotic quantum states and novel electronic devices.

Quantum trajectories in elastic atom-surface scattering: threshold and selective adsorption resonances.

PubMed

Sanz, A S; Miret-Artés, S

2005-01-01

The elastic resonant scattering of He atoms off the Cu(117) surface is fully described with the formalism of quantum trajectories provided by Bohmian mechanics. Within this theory of quantum motion, the concept of trapping is widely studied and discussed. Classically, atoms undergo impulsive collisions with the surface, and then the trapped motion takes place covering at least two consecutive unit cells. However, from a Bohmian viewpoint, atom trajectories can smoothly adjust to the equipotential energy surface profile in a sort of sliding motion; thus the trapping process could eventually occur within one single unit cell. In particular, both threshold and selective adsorption resonances are explained by means of this quantum trapping considering different space and time scales. Furthermore, a mapping between each region of the (initial) incoming plane wave and the different parts of the diffraction and resonance patterns can be easily established, an important issue only provided by a quantum trajectory formalism. (c) 2005 American Institute of Physics.

An efficient finite element with layerwise mechanics for smart piezoelectric composite and sandwich shallow shells

NASA Astrophysics Data System (ADS)

Yasin, M. Yaqoob; Kapuria, S.

2014-01-01

In this work, we present a new efficient four-node finite element for shallow multilayered piezoelectric shells, considering layerwise mechanics and electromechanical coupling. The laminate mechanics is based on the zigzag theory that has only seven kinematic degrees of freedom per node. The normal deformation of the piezoelectric layers under the electric field is accounted for without introducing any additional deflection variables. A consistent quadratic variation of the electric potential across the piezoelectric layers with the provision of satisfying the equipotential condition of electroded surfaces is adopted. The performance of the new element is demonstrated for the static response under mechanical and electric potential loads, and for free vibration response of smart shells under different boundary conditions. The predictions are found to be very close to the three dimensional piezoelasticity solutions for hybrid shells made of not only single-material composite substrates, but also sandwich substrates with a soft core for which the equivalent single layer (ESL) theories perform very badly.

Ion extraction from a plasma

NASA Technical Reports Server (NTRS)

Aston, G.; Wilbur, P. J.

1981-01-01

The physical processes governing ion extraction from a plasma have been examined experimentally. The screen hole plasma sheath (the transition region wherein significant ion acceleration and complete electron retardation occurs) has been defined by equipotential plots for a variety of ion accelerator system geometries and operating conditions. It was found that the screen hole plasma sheath extends over a large distance, and influences ion and electron trajectories at least 15 Debye lengths within the discharge chamber. The electron density variation within the screen hole plasma sheath satisfied a Maxwell-Boltzmann density distribution at an effective electron temperature dependent on the discharge plasma primary-to-Maxwellian electron density ratio. Plasma ion flow up to and through the sheath was predominantly one-dimensional, and the ions entered the sheath region with a modified Bohm velocity. Low values of the screen grid thickness to screen hole diameter ratio were found to give good ion focusing and high extracted ion currents because of the effect of screen webbing on ion focusing.

Secondary electron emission from a dielectric film subjected to an electric field. M.S. Thesis

NASA Technical Reports Server (NTRS)

Quoc-Nguyen, N.

1977-01-01

An electric field in the range of 0.3,3.3 kV/mm is created normal to a thin film FEP teflon sample which accumulates potential of up to 8.8, 13.7 or 18.3 kV when exposed to an electron beam having energy of 10.0, 15.0 or 20.0 kV, respectively. It is found that the secondary electron emission from the charged sample varies with field. The threshold voltage, at which the secondary electron emission coefficient sigma is unity, drops down from a low field value of 13.73 kV to a high field value of 13.11 kV for a 15.0 kV beam. A computational technique was developed that generates equipotential lines or contours and field vectors above a plane where potential is known. The utilization of conformal transformations allows the extension of the technique to configurations which map into a plane.

Focusing a fountain of neutral cesium atoms with an electrostatic lens triplet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalnins, Juris G.; Amini, Jason M.; Gould, Harvey

2005-10-15

An electrostatic lens with three focusing elements in an alternating-gradient configuration is used to focus a fountain of cesium atoms in their ground (strong-field-seeking) state. The lens electrodes are shaped to produce only sextupole plus dipole equipotentials which avoids adding the unnecessary nonlinear forces present in cylindrical lenses. Defocusing between lenses is greatly reduced by having all of the main electric fields point in the same direction and be of nearly equal magnitude. The addition of the third lens gave us better control of the focusing strength in the two transverse planes and allowed focusing of the beam to halfmore » the image size in both planes. The beam envelope was calculated for lens voltages selected to produced specific focusing properties. The calculations, starting from first principles, were compared with measured beam sizes and found to be in good agreement. Application to fountain experiments, atomic clocks, and focusing polar molecules in strong-field-seeking states is discussed.« less

Experimental Investigation of Electron Cloud Containment in a Nonuniform Magnetic Field

NASA Technical Reports Server (NTRS)

Eninger, J. E.

1974-01-01

Dense clouds of electrons were generated and studied in an axisymmetric, nonuniform magnetic field created by a short solenoid. The operation of the experiment was similar to that of a low-pressure (approximately 0.000001 Torr) magnetron discharge. Discharge current characteristics are presented as a function of pressure, magnetic field strength, voltage, and cathode end-plate location. The rotation of the electron cloud is determined from the frequency of diocotron waves. In the space charge saturated regime of operation, the cloud is found to rotate as a solid body with frequency close to V sub a/phi sub a where V sub a is the anode voltage and phi suba is the total magnetic flux. This result indicates that, in regions where electrons are present, the magnetic field lines are electrostatic equipotentials (E bar, B bar = 0). Equilibrium electron density distributions suggested by this conditions are integrated with respect to total ionizing power and are found consistent with measured discharge currents.

Validation of recent geopotential models in Tierra Del Fuego

NASA Astrophysics Data System (ADS)

Gomez, Maria Eugenia; Perdomo, Raul; Del Cogliano, Daniel

2017-10-01

This work presents a validation study of global geopotential models (GGM) in the region of Fagnano Lake, located in the southern Andes. This is an excellent area for this type of validation because it is surrounded by the Andes Mountains, and there is no terrestrial gravity or GNSS/levelling data. However, there are mean lake level (MLL) observations, and its surface is assumed to be almost equipotential. Furthermore, in this article, we propose improved geoid solutions through the Residual Terrain Modelling (RTM) approach. Using a global geopotential model, the results achieved allow us to conclude that it is possible to use this technique to extend an existing geoid model to those regions that lack any information (neither gravimetric nor GNSS/levelling observations). As GGMs have evolved, our results have improved progressively. While the validation of EGM2008 with MLL data shows a standard deviation of 35 cm, GOCO05C shows a deviation of 13 cm, similar to the results obtained on land.

Spatial potential ripples of azimuthal surface modes in topological insulator Bi 2Te 3 nanowires

DOE PAGES

Muñoz Rojo, Miguel; Zhang, Yingjie; Manzano, Cristina V.; ...

2016-01-11

Topological insulators (TI) nanowires (NW) are an emerging class of structures, promising both novel quantum effects and potential applications in low-power electronics, thermoelectrics and spintronics. However, investigating the electronic states of TI NWs is complicated, due to their small lateral size, especially at room temperature. Here, we perform scanning probe based nanoscale imaging to resolve the local surface potential landscapes of Bi 2Te 3 nanowires (NWs) at 300 K. We found equipotential rings around the NWs perimeter that we attribute to azimuthal 1D modes. Along the NW axis, these modes are altered, forming potential ripples in the local density ofmore » states, due to intrinsic disturbances. Potential mapping of electrically biased NWs enabled us to accurately determine their conductivity which was found to increase with the decrease of NW diameter, consistent with surface dominated transport. Finally, our results demonstrate that TI NWs can pave the way to both exotic quantum states and novel electronic devices.« less

Equilibrium configurations of the conducting liquid surface in a nonuniform electric field

NASA Astrophysics Data System (ADS)

Zubarev, N. M.; Zubareva, O. V.

2011-01-01

Possible equilibrium configurations of the free surface of a conducting liquid deformed by a nonuniform external electric field are investigated. The liquid rests on an electrode that has the shape of a dihedral angle formed by two intersecting equipotential half-planes (conducting wedge). It is assumed that the problem has plane symmetry: the surface is invariant under shift along the edge of the dihedral angle. A one-parametric family of exact solutions for the shape of the surface is found in which the opening angle of the region above the wedge serves as a parameter. The solutions are valid when the pressure difference between the inside and outside of the liquid is zero. For an arbitrary pressure difference, approximate solutions to the problem are constructed and it is demonstrated the approximation error is small. It is found that, when the potential difference exceeds a certain threshold value, equilibrium solutions are absent. In this case, the region occupied by the liquid disintegrates, the disintegration scenario depending on the opening angle.

The impact of change in albumin assay on reference intervals, prevalence of 'hypoalbuminaemia' and albumin prescriptions.

PubMed

Coley-Grant, Deon; Herbert, Mike; Cornes, Michael P; Barlow, Ian M; Ford, Clare; Gama, Rousseau

2016-01-01

We studied the impact on reference intervals, classification of patients with hypoalbuminaemia and albumin infusion prescriptions on changing from a bromocresol green (BCG) to a bromocresol purple (BCP) serum albumin assay. Passing-Bablok regression analysis and Bland-Altman plot were used to compare Abbott BCP and Roche BCG methods. Linear regression analysis was used to compare in-house and an external laboratory Abbott BCP serum albumin results. Reference intervals for Abbott BCP serum albumin were derived in two different laboratories using pathology data from adult patients in primary care. Prescriptions for 20% albumin infusions were compared one year before and one year after changing the albumin method. Abbott BCP assay had a negative bias of approximately 6 g/L compared with Roche BCG method.There was good agreement (y = 1.04 x - 1.03; R(2 )= 0.9933) between in-house and external laboratory Abbott BCP results. Reference intervals for the serum albumin Abbott BCP assay were 31-45 g/L, different to those recommended by Pathology Harmony and the manufacturers (35-50 g/L). Following the change in method there was a large increase in the number of patients classified as hypoalbuminaemic using Pathology Harmony references intervals (32%) but not when retrospectively compared to locally derived reference intervals (16%) compared with the previous year (12%). The method change was associated with a 44.6% increase in albumin prescriptions. This equated to an annual increase in expenditure of £35,234. We suggest that serum albumin reference intervals be method specific to prevent misclassification of albumin status in patients. Change in albumin methodology may have significant impact on hospital resources. © The Author(s) 2015.

Genotype 3 is the predominant hepatitis C genotype in a multi-ethnic Asian population in Malaysia.

PubMed

Ho, Shiaw-Hooi; Ng, Kee-Peng; Kaur, Harvinder; Goh, Khean-Lee

2015-06-01

Genotypes of hepatitis C virus (HCV) are distributed differently across the world. There is a paucity of such data in a multi-ethnic Asian population like Malaysia. The objectives of this study were to determine the distribution of HCV genotypes between major ethnic groups and to ascertain their association with basic demographic variables like age and gender. This was a cross-sectional prospective study conducted from September 2007 to September 2013. Consecutive patients who were detected to have anti-HCV antibodies in the University of Malaya Medical Centre were included and tested for the presence of HCV RNA using Roche Cobas Amplicor Analyzer and HCV genotype using Roche single Linear Array HCV Genotyping strip. Five hundred and ninety-six subjects were found to have positive anti-HCV antibodies during this period of time. However, only 396 (66.4%) were HCV RNA positive and included in the final analysis. Our results showed that HCV genotype 3 was the predominant genotype with overall frequency of 61.9% followed by genotypes 1 (35.9%), 2 (1.8%) and 6 (0.5%). There was a slightly higher prevalence of HCV genotype 3 among the Malays when compared to the Chinese (P=0.043). No other statistical significant differences were observed in the distribution of HCV genotypes among the major ethnic groups. There was also no association between the predominant genotypes and basic demographic variables. In a multi-ethnic Asian society in Malaysia, genotype 3 is the predominant genotype among all the major ethnic groups with genotype 1 as the second commonest genotype. Both genotypes 2 and 6 are uncommon. Neither genotype 4 nor 5 was detected. There is no identification of HCV genotype according to ethnic origin, age and gender.

Validation of a Human Papillomavirus (HPV) DNA Cervical Screening Test That Provides Expanded HPV Typing.

PubMed

Demarco, Maria; Carter-Pokras, Olivia; Hyun, Noorie; Castle, Philip E; He, Xin; Dallal, Cher M; Chen, Jie; Gage, Julia C; Befano, Brian; Fetterman, Barbara; Lorey, Thomas; Poitras, Nancy; Raine-Bennett, Tina R; Wentzensen, Nicolas; Schiffman, Mark

2018-05-01

As cervical cancer screening shifts from cytology to human papillomavirus (HPV) testing, a major question is the clinical value of identifying individual HPV types. We aimed to validate Onclarity (Becton Dickinson Diagnostics, Sparks, MD), a nine-channel HPV test recently approved by the FDA, by assessing (i) the association of Onclarity types/channels with precancer/cancer; (ii) HPV type/channel agreement between the results of Onclarity and cobas (Roche Molecular Systems, Pleasanton, CA), another FDA-approved test; and (iii) Onclarity typing for all types/channels compared to typing results from a research assay (linear array [LA]; Roche). We compared Onclarity to histopathology, cobas, and LA. We tested a stratified random sample ( n = 9,701) of discarded routine clinical specimens that had tested positive by Hybrid Capture 2 (HC2; Qiagen, Germantown, MD). A subset had already been tested by cobas and LA ( n = 1,965). Cervical histopathology was ascertained from electronic health records. Hierarchical Onclarity channels showed a significant linear association with histological severity. Onclarity and cobas had excellent agreement on partial typing of HPV16, HPV18, and the other 12 types as a pool (sample-weighted kappa value of 0.83); cobas was slightly more sensitive for HPV18 and slightly less sensitive for the pooled high-risk types. Typing by Onclarity showed excellent agreement with types and groups of types identified by LA (kappa values from 0.80 for HPV39/68/35 to 0.97 for HPV16). Onclarity typing results corresponded well to histopathology and to an already validated HPV DNA test and could provide additional clinical typing if such discrimination is determined to be clinically desirable. This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply.

Doubling immunochemistry laboratory testing efficiency with the cobas e 801 module while maintaining consistency in analytical performance.

PubMed

Findeisen, P; Zahn, I; Fiedler, G M; Leichtle, A B; Wang, S; Soria, G; Johnson, P; Henzell, J; Hegel, J K; Bendavid, C; Collet, N; McGovern, M; Klopprogge, K

2018-06-04

The new immunochemistry cobas e 801 module (Roche Diagnostics) was developed to meet increasing demands on routine laboratories to further improve testing efficiency, while maintaining high quality and reliable data. During a non-interventional multicenter evaluation study, the overall performance, functionality and reliability of the new module was investigated under routine-like conditions. It was tested as a dedicated immunochemistry system at four sites and as a consolidator combined with clinical chemistry at three sites. We report on testing efficiency and analytical performance of the new module. Evaluation of sample workloads with site-specific routine request patterns demonstrated increased speed and almost doubled throughput (maximal 300 tests per h), thus revealing that one cobas e 801 module can replace two cobas e 602 modules while saving up to 44% floor space. Result stability was demonstrated by QC analysis per assay throughout the study. Precision testing over 21 days yielded excellent results within and between labs, and, method comparison performed versus the cobas e 602 module routine results showed high consistency of results for all assays under study. In a practicability assessment related to performance and handling, 99% of graded features met (44%) or even exceeded (55%) laboratory expectations, with enhanced reagent management and loading during operation being highlighted. By nearly doubling immunochemistry testing efficiency on the same footprint as a cobas e 602 module, the new module has a great potential to further consolidate and enhance laboratory testing while maintaining high quality analytical performance with Roche platforms. Copyright © 2018 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Quantitative analysis of cytomegalovirus (CMV) viremia using the pp65 antigenemia assay and the COBAS AMPLICOR CMV MONITOR PCR test after blood and marrow allogeneic transplantation.

PubMed

Boivin, G; Bélanger, R; Delage, R; Béliveau, C; Demers, C; Goyette, N; Roy, J

2000-12-01

The performance of a commercially available qualitative PCR test for plasma (AMPLICOR CMV Test; Roche Diagnostics) and a quantitative PCR test for plasma and leukocytes (COBAS AMPLICOR CMV MONITOR Test; Roche Diagnostics) was evaluated with samples from 50 blood or marrow allogeneic transplant recipients who received short courses of sequential ganciclovir therapy (2 weeks intravenously followed by 2 weeks orally) based on a positive cytomegalovirus (CMV) pp65 antigenemia (AG) assay. The number of persons with a positive CMV test was significantly higher for leukocyte-based assays (AG, 67.5%; PCR, 62.5%) compared to both quantitative and qualitative PCR tests of plasma (42.5 and 35%, respectively). One person developed CMV disease during the study despite a negative AG assay; in this particular case, all PCR assays were found to be positive 10 days before his death. There was a trend for earlier positivity after transplantation and more rapid negativity after initiation of ganciclovir for the tests performed on leukocytes. The mean number of CMV copies as assessed by PCR was significantly higher in leukocytes than in plasma (P = 0.02). Overall, excellent agreement (kappa coefficient, >0.75) was found only between the two PCR assays (qualitative and quantitative) based on plasma. These results suggest that either the pp65 AG assay or the COBAS AMPLICOR CMV MONITOR Test using leukocytes could be used to safely monitor CMV viremia in related allogeneic blood or marrow transplant recipients. Such a strategy will result in preemptive treatment for about two-thirds of the persons with a relatively low rate (<33%) of secondary viremic episodes following short courses of ganciclovir therapy.

NMR relaxation induced by iron oxide particles: testing theoretical models.

PubMed

Gossuin, Y; Orlando, T; Basini, M; Henrard, D; Lascialfari, A; Mattea, C; Stapf, S; Vuong, Q L

2016-04-15

Superparamagnetic iron oxide particles find their main application as contrast agents for cellular and molecular magnetic resonance imaging. The contrast they bring is due to the shortening of the transverse relaxation time T 2 of water protons. In order to understand their influence on proton relaxation, different theoretical relaxation models have been developed, each of them presenting a certain validity domain, which depends on the particle characteristics and proton dynamics. The validation of these models is crucial since they allow for predicting the ideal particle characteristics for obtaining the best contrast but also because the fitting of T 1 experimental data by the theory constitutes an interesting tool for the characterization of the nanoparticles. In this work, T 2 of suspensions of iron oxide particles in different solvents and at different temperatures, corresponding to different proton diffusion properties, were measured and were compared to the three main theoretical models (the motional averaging regime, the static dephasing regime, and the partial refocusing model) with good qualitative agreement. However, a real quantitative agreement was not observed, probably because of the complexity of these nanoparticulate systems. The Roch theory, developed in the motional averaging regime (MAR), was also successfully used to fit T 1 nuclear magnetic relaxation dispersion (NMRD) profiles, even outside the MAR validity range, and provided a good estimate of the particle size. On the other hand, the simultaneous fitting of T 1 and T 2 NMRD profiles by the theory was impossible, and this occurrence constitutes a clear limitation of the Roch model. Finally, the theory was shown to satisfactorily fit the deuterium T 1 NMRD profile of superparamagnetic particle suspensions in heavy water.

High-mass X-ray binary populations. 1: Galactic modeling

NASA Technical Reports Server (NTRS)

Dalton, William W.; Sarazin, Craig L.

1995-01-01

Modern stellar evolutionary tracks are used to calculate the evolution of a very large number of massive binary star systems (M(sub tot) greater than or = 15 solar mass) which cover a wide range of total masses, mass ratios, and starting separations. Each binary is evolved accounting for mass and angular momentum loss through the supernova of the primary to the X-ray binary phase. Using the observed rate of star formation in our Galaxy and the properties of massive binaries, we calculate the expected high-mass X-ray binary (HMXRB) population in the Galaxy. We test various massive binary evolutionary scenarios by comparing the resulting HMXRB predictions with the X-ray observations. A major goal of this study is the determination of the fraction of matter lost from the system during the Roche lobe overflow phase. Curiously, we find that the total numbers of observable HMXRBs are nearly independent of this assumed mass-loss fraction, with any of the values tested here giving acceptable agreement between predicted and observed numbers. However, comparison of the period distribution of our HMXRB models with the observed period distribution does reveal a distinction among the various models. As a result of this comparison, we conclude that approximately 70% of the overflow matter is lost from a massive binary system during mass transfer in the Roche lobe overflow phase. We compare models constructed assuming that all X-ray emission is due to accretion onto the compact object from the donor star's wind with models that incorporate a simplified disk accretion scheme. By comparing the results of these models with observations, we conclude that the formation of disks in HMXRBs must be relatively common. We also calculate the rate of formation of double degenerate binaries, high velocity detached compact objects, and Thorne-Zytkow objects.

Multicenter Comparative Evaluation of Five Commercial Methods for Toxoplasma DNA Extraction from Amniotic Fluid▿

PubMed Central

Yera, H.; Filisetti, D.; Bastien, P.; Ancelle, T.; Thulliez, P.; Delhaes, L.

2009-01-01

Over the past few years, a number of new nucleic acid extraction methods and extraction platforms using chemistry combined with magnetic or silica particles have been developed, in combination with instruments to facilitate the extraction procedure. The objective of the present study was to investigate the suitability of these automated methods for the isolation of Toxoplasma gondii DNA from amniotic fluid (AF). Therefore, three automated procedures were compared to two commercialized manual extraction methods. The MagNA Pure Compact (Roche), BioRobot EZ1 (Qiagen), and easyMAG (bioMérieux) automated procedures were compared to two manual DNA extraction kits, the QIAamp DNA minikit (Qiagen) and the High Pure PCR template preparation kit (Roche). Evaluation was carried out with two specific Toxoplasma PCRs (targeting the 529-bp repeat element), inhibitor search PCRs, and human beta-globin PCRs. The samples each consisted of 4 ml of AF with or without a calibrated Toxoplasma gondii RH strain suspension (0, 1, 2.5, 5, and 25 tachyzoites/ml). All PCR assays were laboratory-developed real-time PCR assays, using either TaqMan or fluorescent resonance energy transfer probes. A total of 1,178 PCRs were performed, including 978 Toxoplasma PCRs. The automated and manual methods were similar in sensitivity for DNA extraction from T. gondii at the highest concentration (25 Toxoplasma gondii cells/ml). However, our results showed that the DNA extraction procedures led to variable efficacy in isolating low concentrations of tachyzoites in AF samples (<5 Toxoplasma gondii cells/ml), a difference that might have repercussions since low parasite concentrations in AF exist and can lead to congenital toxoplasmosis. PMID:19846633

CLSI-based transference of the CALIPER database of pediatric reference intervals from Abbott to Beckman, Ortho, Roche and Siemens Clinical Chemistry Assays: direct validation using reference samples from the CALIPER cohort.

PubMed

Estey, Mathew P; Cohen, Ashley H; Colantonio, David A; Chan, Man Khun; Marvasti, Tina Binesh; Randell, Edward; Delvin, Edgard; Cousineau, Jocelyne; Grey, Vijaylaxmi; Greenway, Donald; Meng, Qing H; Jung, Benjamin; Bhuiyan, Jalaluddin; Seccombe, David; Adeli, Khosrow

2013-09-01

The CALIPER program recently established a comprehensive database of age- and sex-stratified pediatric reference intervals for 40 biochemical markers. However, this database was only directly applicable for Abbott ARCHITECT assays. We therefore sought to expand the scope of this database to biochemical assays from other major manufacturers, allowing for a much wider application of the CALIPER database. Based on CLSI C28-A3 and EP9-A2 guidelines, CALIPER reference intervals were transferred (using specific statistical criteria) to assays performed on four other commonly used clinical chemistry platforms including Beckman Coulter DxC800, Ortho Vitros 5600, Roche Cobas 6000, and Siemens Vista 1500. The resulting reference intervals were subjected to a thorough validation using 100 reference specimens (healthy community children and adolescents) from the CALIPER bio-bank, and all testing centers participated in an external quality assessment (EQA) evaluation. In general, the transferred pediatric reference intervals were similar to those established in our previous study. However, assay-specific differences in reference limits were observed for many analytes, and in some instances were considerable. The results of the EQA evaluation generally mimicked the similarities and differences in reference limits among the five manufacturers' assays. In addition, the majority of transferred reference intervals were validated through the analysis of CALIPER reference samples. This study greatly extends the utility of the CALIPER reference interval database which is now directly applicable for assays performed on five major analytical platforms in clinical use, and should permit the worldwide application of CALIPER pediatric reference intervals. Copyright © 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Prevalence of hepatitis C infection among intravenous drug users in Shanghai.

PubMed

Tao, Yan-Lin; Tang, Yu-Fan; Qiu, Jian-Ping; Cai, Xiao-Feng; Shen, Xiao-Ting; Wang, Ya-Xin; Zhao, Xue-Tao

2013-08-28

To characterize the prevalence of hepatitis C virus (HCV) infection among Chinese intravenous drug users (IDUs). A total of 432 adult IDUs (95 women and 337 men) in Shanghai were included in the study. The third-generation Elecsys Anti-HCV assay (Roche Diagnostics GmbH, Sandhofer Strasse 116, D-68305, Mannheim, Germany) was used to screen for antibodies against HCV. The RIBA strip, a supplemental anti-HCV test with high specificity, was performed on all of the samples that tested positive during the initial screening. All of the anti-HCV positive samples were analyzed with a Cobas TaqMan 48 Analyzer (Roche Diagnostics) for direct detection of HCV RNA. All of the HCV RNA-positive samples were sequenced for genotype determination. The preliminary screening identified 262 (60.6%) subjects who were seropositive for HCV. Of the 62 females and 200 males seropositive subjects, 16 (16.7%) and 65 (19.3%), respectively, were confirmed by RIBA, yielding an overall HCV seropositive rate of 18.8%. Four female (6.5%) and 14 male (7.0%) subjects tested positive for HCV RNA, indicating an active infection rate of 4.2% for the entire study population. The 18 HCV RNA-positive serum samples were genotyped. Seven individuals were genotype 1b, and four were genotype 1a. One individual each was infected with genotypes 2a, 2b and 3a. Four subjects were co-infected with multiple strains: two with genotypes 1a and 2a, and two with genotypes 1b and 2a. The active infection rate among HCV-seropositive individuals was 22.2%, which was significantly lower than most estimates. The prevalence of HCV is relatively low among IDUs in Shanghai, with a spontaneous recovery rate much higher than previous estimates.

Evaluation of the clinical sensitivity for the quantification of human immunodeficiency virus type 1 RNA in plasma: Comparison of the new COBAS TaqMan HIV-1 with three current HIV-RNA assays--LCx HIV RNA quantitative, VERSANT HIV-1 RNA 3.0 (bDNA) and COBAS AMPLICOR HIV-1 Monitor v1.5.

PubMed

Katsoulidou, Antigoni; Petrodaskalaki, Maria; Sypsa, Vana; Papachristou, Eleni; Anastassopoulou, Cleo G; Gargalianos, Panagiotis; Karafoulidou, Anastasia; Lazanas, Marios; Kordossis, Theodoros; Andoniadou, Anastasia; Hatzakis, Angelos

2006-02-01

The COBAS TaqMan HIV-1 test (Roche Diagnostics) was compared with the LCx HIV RNA quantitative assay (Abbott Laboratories), the Versant HIV-1 RNA 3.0 (bDNA) assay (Bayer) and the COBAS Amplicor HIV-1 Monitor v1.5 test (Roche Diagnostics), using plasma samples of various viral load levels from HIV-1-infected individuals. In the comparison of TaqMan with LCx, TaqMan identified as positive 77.5% of the 240 samples versus 72.1% identified by LCx assay, while their overall agreement was 94.6% and the quantitative results of samples that were positive by both methods were strongly correlated (r=0.91). Similarly, in the comparison of TaqMan with bDNA 3.0, both methods identified 76.3% of the 177 samples as positive, while their overall agreement was 95.5% and the quantitative results of samples that were positive by both methods were strongly correlated (r=0.95). Finally, in the comparison of TaqMan with Monitor v1.5, TaqMan identified 79.5% of the 156 samples as positive versus 80.1% identified by Monitor v1.5, while their overall agreement was 95.5% and the quantitative results of samples that were positive by both methods were strongly correlated (r=0.96). In conclusion, the new COBAS TaqMan HIV-1 test showed excellent agreement with other widely used commercially available tests for the quantitation of HIV-1 viral load.

Gravity-darkening exponents in semi-detached binary systems from their photometric observations. II.

NASA Astrophysics Data System (ADS)

Djurašević, G.; Rovithis-Livaniou, H.; Rovithis, P.; Georgiades, N.; Erkapić, S.; Pavlović, R.

2006-01-01

This second part of our study concerning gravity-darkening presents the results for 8 semi-detached close binary systems. From the light-curve analysis of these systems the exponent of the gravity-darkening (GDE) for the Roche lobe filling components has been empirically derived. The method used for the light-curve analysis is based on Roche geometry, and enables simultaneous estimation of the systems' parameters and the gravity-darkening exponents. Our analysis is restricted to the black-body approximation which can influence in some degree the parameter estimation. The results of our analysis are: 1) For four of the systems, namely: TX UMa, β Per, AW Cam and TW Cas, there is a very good agreement between empirically estimated and theoretically predicted values for purely convective envelopes. 2) For the AI Dra system, the estimated value of gravity-darkening exponent is greater, and for UX Her, TW And and XZ Pup lesser than corresponding theoretical predictions, but for all mentioned systems the obtained values of the gravity-darkening exponent are quite close to the theoretically expected values. 3) Our analysis has proved generally that with the correction of the previously estimated mass ratios of the components within some of the analysed systems, the theoretical predictions of the gravity-darkening exponents for stars with convective envelopes are highly reliable. The anomalous values of the GDE found in some earlier studies of these systems can be considered as the consequence of the inappropriate method used to estimate the GDE. 4) The empirical estimations of GDE given in Paper I and in the present study indicate that in the light-curve analysis one can apply the recent theoretical predictions of GDE with high confidence for stars with both convective and radiative envelopes.

Validation of an automated method for compounding monoclonal antibody patient doses

PubMed Central

Peters, Bas J.M.; Capelle, Martinus A.H.; Arvinte, Tudor; van de Garde, Ewoudt M.W.

2013-01-01

Automation robots have recently come to the market as an alternative for manual compounding of drugs for intravenous administration. Our aim was to assess whether robotic compounding can be performed with monoclonal antibodies (mAbs) without influencing the aggregation state of the proteins. Three frequently used mAbs were studied: infliximab (Remicade®, Janssen Biotech) and trastuzumab (Herceptin®, Roche) in lyophilised form, and bevacizumab (Avastin®, Roche) as a liquid formulation stored at 2°C to 8°C. The effects of different procedures to prepare the patient doses on antibody aggregation were evaluated. Remicade® and Herceptin® were reconstituted both manually and by a robotic arm (i.v.STATION®, Health Robotics). Additionally, the influence of vigorous shaking during reconstitution was investigated. The effects of rapid aspiration and dispensing on antibody aggregation were investigated for all three mAbs. Aggregation state was assessed by UV-Vis absorbance, 90° light scatter, fluorescence spectroscopy, Nile red fluorescence microscopy, and field flow fractionation without cross and focus flow. Robotic reconstituted samples showed similar findings compared with manual reconstitution if performed exactly according to the summary of product characteristics (SPC). Vials that were vigorously shaken showed a significant increase in aggregates. Similarly, rapid aspiration/dispense cycles resulted in a strong increase in the number and sizes of aggregates for all three mAbs; this result was observed after just one rapid aspiration/dispense cycle. Our study showed that robotic compounding of mAbs is feasible if the robot is exactly programmed according to the SPC, indicating that robotic compounding can be used to achieve reproducible high-quality compounding for delicate formulations. PMID:23255057

EVOLUTION OF CATACLYSMIC VARIABLES AND RELATED BINARIES CONTAINING A WHITE DWARF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalomeni, B.; Rappaport, S.; Molnar, M.

We present a binary evolution study of cataclysmic variables (CVs) and related systems with white dwarf (WD) accretors, including for example, AM CVn systems, classical novae, supersoft X-ray sources (SXSs), and systems with giant donor stars. Our approach intentionally avoids the complications associated with population synthesis algorithms, thereby allowing us to present the first truly comprehensive exploration of all of the subsequent binary evolution pathways that zero-age CVs might follow (assuming fully non-conservative, Roche-lobe overflow onto an accreting WD) using the sophisticated binary stellar evolution code MESA. The grid consists of 56,000 initial models, including 14 WD accretor masses, 43more » donor-star masses (0.1–4.7 M {sub ⊙}), and 100 orbital periods. We explore evolution tracks in the orbital period and donor-mass ( P {sub orb}– M {sub don}) plane in terms of evolution dwell times, masses of the WD accretor, accretion rate, and chemical composition of the center and surface of the donor star. We report on the differences among the standard CV tracks, those with giant donor stars, and ultrashort period systems. We show where in parameter space one can expect to find SXSs, present a diagnostic to distinguish among different evolutionary paths to forming AM CVn binaries, quantify how the minimum orbital period in CVs depends on the chemical composition of the donor star, and update the P {sub orb}( M {sub wd}) relation for binaries containing WDs whose progenitors lost their envelopes via stable Roche-lobe overflow. Finally, we indicate where in the P {sub orb}– M {sub don} the accretion disks will tend to be stable against the thermal-viscous instability, and where gravitational radiation signatures may be found with LISA.« less

Reliability of the rapid bedside whole-blood quantitative cardiac troponin T assay in the diagnosis of myocardial injury in patients with acute coronary syndrome.

PubMed

Saadeddin, Salam; Habbab, Mohammed; Siddieg, Hisham; Fayomi, Mahmoud; Dafterdar, Rofaida

2004-03-01

A rapid bedside whole-blood quantitative cTnT assay has recently been developed. We evaluated the reliability of this test for the diagnosis of myocardial injury in patients with acute coronary syndrome (ACS). Whole-blood cTnT levels were measured in 96 patients with ACS using the Roche Cardiac Reader(R) rapid bedside assay device, and the results were compared with serum cTnT levels in the same patients measured by the Roche Elecsys(R) Immunoanalyzer. There were 50 patients with clinical evidence of myocardial injury and 56 without. From the qualitative point of view (reporting negative or positive tests), the results of the rapid bedside tests were identical to those obtained by the serum immunoanalyzer. From quantitative the point of view, the rapid bedside tests could not measure exact values below 0.1 ng/ml (reported negative) or above 2.0 ng/ml (reported >2.0). The measurements made by the rapid bedside tests within the range of 0.1 to 2.0 ng/ml correlated well with those of the serum immunoanalyzer (Cardiac Reader(R) cTnT=0.61, Elecsys(R) cTnT+0.12; r=0.88), but their mean values were significantly lower (1.20I0.71 vs. 1.41I1.03, p=0.0007). The rapid bedside cTnT assay correlates well with immunoanalyzer measurements between the values of 0.1 and 2.0 ng/ml. However, they tend to give significantly lower values and fail to give exact values below 0.1 and above 2.0 ng/ml, which may affect their performance in monitoring and managing patients with ACS, and limit their use in predicting outcome.

The crowded magnetosphere of the post-common-envelope binary QS Virginis

NASA Astrophysics Data System (ADS)

Parsons, S. G.; Hill, C. A.; Marsh, T. R.; Gänsicke, B. T.; Watson, C. A.; Steeghs, D.; Dhillon, V. S.; Littlefair, S. P.; Copperwheat, C. M.; Schreiber, M. R.; Zorotovic, M.

2016-05-01

We present high-speed photometry and high-resolution spectroscopy of the eclipsing post-common-envelope binary QS Virginis (QS Vir). Our Ultraviolet and Visual Echelle Spectrograph (UVES) spectra span multiple orbits over more than a year and reveal the presence of several large prominences passing in front of both the M star and its white dwarf companion, allowing us to triangulate their positions. Despite showing small variations on a time-scale of days, they persist for more than a year and may last decades. One large prominence extends almost three stellar radii from the M star. Roche tomography reveals that the M star is heavily spotted and that these spots are long-lived and in relatively fixed locations, preferentially found on the hemisphere facing the white dwarf. We also determine precise binary and physical parameters for the system. We find that the 14 220 ± 350 K white dwarf is relatively massive, 0.782 ± 0.013 M⊙, and has a radius of 0.010 68 ± 0.000 07 R⊙, consistent with evolutionary models. The tidally distorted M star has a mass of 0.382 ± 0.006 M⊙ and a radius of 0.381 ± 0.003 R⊙, also consistent with evolutionary models. We find that the magnesium absorption line from the white dwarf is broader than expected. This could be due to rotation (implying a spin period of only ˜700 s), or due to a weak (˜100 kG) magnetic field, we favour the latter interpretation. Since the M star's radius is still within its Roche lobe and there is no evidence that it is overinflated, we conclude that QS Vir is most likely a pre-cataclysmic binary just about to become semidetached.

Roche-lobe overflow systems powered by black holes in young star clusters: the importance of dynamical exchanges

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mapelli, Michela; Zampieri, Luca, E-mail: michela.mapelli@oapd.inaf.it

2014-10-10

We have run 600 N-body simulations of intermediate-mass (∼3500 M {sub ☉}) young star clusters (SCs; with three different metallicities (Z = 0.01, 0.1, and 1 Z {sub ☉}). The simulations include the dependence of stellar properties and stellar winds on metallicity. Massive stellar black holes (MSBHs) with mass >25 M {sub ☉} are allowed to form through direct collapse of very massive metal-poor stars (Z < 0.3 Z {sub ☉}). We focus on the demographics of black hole (BH) binaries that undergo mass transfer via Roche lobe overflow (RLO). We find that 44% of all binaries that undergo anmore » RLO phase (RLO binaries) formed through dynamical exchange. RLO binaries that formed via exchange (RLO-EBs) are powered by more massive BHs than RLO primordial binaries (RLO-PBs). Furthermore, the RLO-EBs tend to start the RLO phase later than the RLO-PBs. In metal-poor SCs (0.01-0.1 Z {sub ☉}), >20% of all RLO binaries are powered by MSBHs. The vast majority of RLO binaries powered by MSBHs are RLO-EBs. We have produced optical color-magnitude diagrams of the simulated RLO binaries, accounting for the emission of both the donor star and the irradiated accretion disk. We find that RLO-PBs are generally associated with bluer counterparts than RLO-EBs. We compare the simulated counterparts with the observed counterparts of nine ultraluminous X-ray sources. We discuss the possibility that IC 342 X-1, Ho IX X-1, NGC 1313 X-2, and NGC 5204 X-1 are powered by an MSBH.« less

UNDERSTANDING THE EVOLUTION OF CLOSE BINARY SYSTEMS WITH RADIO PULSARS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benvenuto, O. G.; De Vito, M. A.; Horvath, J. E., E-mail: obenvenu@fcaglp.unlp.edu.ar, E-mail: adevito@fcaglp.unlp.edu.ar, E-mail: foton@astro.iag.usp.br

We calculate the evolution of close binary systems (CBSs) formed by a neutron star (behaving as a radio pulsar) and a normal donor star, which evolve either to a helium white dwarf (HeWD) or to ultra-short orbital period systems. We consider X-ray irradiation feedback and evaporation due to radio pulsar irradiation. We show that irradiation feedback leads to cyclic mass transfer episodes, allowing CBSs to be observed in between episodes as binary radio pulsars under conditions in which standard, non-irradiated models predict the occurrence of a low-mass X-ray binary. This behavior accounts for the existence of a family of eclipsingmore » binary systems known as redbacks. We predict that redback companions should almost fill their Roche lobe, as observed in PSR J1723-2837. This state is also possible for systems evolving with larger orbital periods. Therefore, binary radio pulsars with companion star masses usually interpreted as larger than expected to produce HeWDs may also result in such quasi-Roche lobe overflow states, rather than hosting a carbon-oxygen WD. We found that CBSs with initial orbital periods of P{sub i} < 1 day evolve into redbacks. Some of them produce low-mass HeWDs, and a subgroup with shorter P{sub i} becomes black widows (BWs). Thus, BWs descend from redbacks, although not all redbacks evolve into BWs. There is mounting observational evidence favoring BW pulsars to be very massive (≳ 2 M {sub ☉}). As they should be redback descendants, redback pulsars should also be very massive, since most of the mass is transferred before this stage.« less

Large-scale transcriptome analysis in chickpea (Cicer arietinum L.), an orphan legume crop of the semi-arid tropics of Asia and Africa.

PubMed

Hiremath, Pavana J; Farmer, Andrew; Cannon, Steven B; Woodward, Jimmy; Kudapa, Himabindu; Tuteja, Reetu; Kumar, Ashish; Bhanuprakash, Amindala; Mulaosmanovic, Benjamin; Gujaria, Neha; Krishnamurthy, Laxmanan; Gaur, Pooran M; Kavikishor, Polavarapu B; Shah, Trushar; Srinivasan, Ramamurthy; Lohse, Marc; Xiao, Yongli; Town, Christopher D; Cook, Douglas R; May, Gregory D; Varshney, Rajeev K

2011-10-01

Chickpea (Cicer arietinum L.) is an important legume crop in the semi-arid regions of Asia and Africa. Gains in crop productivity have been low however, particularly because of biotic and abiotic stresses. To help enhance crop productivity using molecular breeding techniques, next generation sequencing technologies such as Roche/454 and Illumina/Solexa were used to determine the sequence of most gene transcripts and to identify drought-responsive genes and gene-based molecular markers. A total of 103,215 tentative unique sequences (TUSs) have been produced from 435,018 Roche/454 reads and 21,491 Sanger expressed sequence tags (ESTs). Putative functions were determined for 49,437 (47.8%) of the TUSs, and gene ontology assignments were determined for 20,634 (41.7%) of the TUSs. Comparison of the chickpea TUSs with the Medicago truncatula genome assembly (Mt 3.5.1 build) resulted in 42,141 aligned TUSs with putative gene structures (including 39,281 predicted intron/splice junctions). Alignment of ∼37 million Illumina/Solexa tags generated from drought-challenged root tissues of two chickpea genotypes against the TUSs identified 44,639 differentially expressed TUSs. The TUSs were also used to identify a diverse set of markers, including 728 simple sequence repeats (SSRs), 495 single nucleotide polymorphisms (SNPs), 387 conserved orthologous sequence (COS) markers, and 2088 intron-spanning region (ISR) markers. This resource will be useful for basic and applied research for genome analysis and crop improvement in chickpea. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd. No claim to original US government works.

Performance in Measurement of Serum Cystatin C by Laboratories Participating in the College of American Pathologists 2014 CYS Survey.

PubMed

Eckfeldt, John H; Karger, Amy B; Miller, W Greg; Rynders, Gregory P; Inker, Lesley A

2015-07-01

Cystatin C is becoming an increasingly popular biomarker for estimating glomerular filtration rate, and accurate measurements of cystatin C concentrations are necessary for accurate estimates of glomerular filtration rate. To assess the accuracy of cystatin C concentration measurements in laboratories participating in the College of American Pathologists CYS Survey. Two fresh frozen serum pools, the first from apparently healthy donors and the second from patients with chronic kidney disease, were prepared and distributed to laboratories participating in the CYS Survey along with the 2 usual processed human plasma samples. Target values were established for each pool by using 2 immunoassays and ERM DA471/IFCC international reference material. For the normal fresh frozen pool (ERM-DA471/IFCC-traceable target of 0.960 mg/L), the all-method mean (SD, % coefficient of variation [CV]) reported by all of the 123 reporting laboratories was 0.894 mg/L (0.128 mg/L, 14.3%). For the chronic kidney disease pool (ERM-DA471/IFCC-traceable target of 2.37 mg/L), the all-method mean (SD, %CV) was 2.258 mg/L (0.288 mg/L, 12.8%). There were substantial method-specific biases (mean milligram per liter reported for the normal pool was 0.780 for Siemens, 0.870 for Gentian, 0.967 for Roche, 1.061 for Diazyme, and 0.970 for other/not specified reagents; and mean milligram per liter reported for the chronic kidney disease pool was 2.052 for Siemens, 2.312 for Gentian, 2.247 for Roche, 2.909 for Diazyme, and 2.413 for other/not specified reagents). Manufacturers need to improve the accuracy of cystatin C measurement procedures if cystatin C is to achieve its full potential as a biomarker for estimating glomerular filtration rate.

Evaluation of the highly sensitive Roche thyroglobulin II assay and establishment of a reference limit for thyroglobulin-negative patient samples.

PubMed

Rotteveel-de Groot, Dorien M; Ross, H Alec; Janssen, Marcel J R; Netea-Maier, Romana T; Oosting, Janine D; Sweep, Fred C G J; van Herwaarden, Antonius E

2016-08-01

Thyroglobulin (Tg) measurements are used to monitor for residual thyroid tissue in patients with differentiated thyroid cancer (DTC) after thyroidectomy and radioiodine ablative therapy. In recent years highly sensitive Tg assays have been developed. In this study the analytical performance of the new Roche Elecsys Tg II assay was evaluated and compared with the well documented Access2 Tg assay (Beckman-Coulter). Analytical performance was examined using various Clinical and Laboratory Standards Institute (CLSI) evaluation protocols. Tg negative patient sera were used to establish an upper reference limit (URL) for the Elecsys Tg II assay. Non-linearity, drift and carry-over according to CLSI EP10 and EP6 in a measuring range of 0.04-500 ng/mL were non-significant. Total precision according to CLSI EP5 was 10% at a Tg concentration of 0.08 ng/mL. A patient serum comparison performed according to a modified CLSI EP9 protocol showed a significant difference of a factor of approximately 1.4, despite using an identical CRM calibrator. The Elecsys Tg II assay measured Tg with a two-fold higher sensitivity than the Access2 assay. Finally, using human sera without Tg, an URL of 0.05 ng/mL was determined. In our hands the highly sensitive Elecsys Tg II assay shows a good analytical performance and a higher sensitivity compared to the Access2 Tg assay. An URL of 0.05 ng/mL for the Elecsys Tg II assay was determined which may improve the clinical utility of the assay for the detection of residual DTC or disease recurrence.

Evaluation of the Roche prototype 454 HIV-1 ultradeep sequencing drug resistance assay in a routine diagnostic laboratory.

PubMed

Garcia-Diaz, A; Guerrero-Ramos, A; McCormick, A L; Macartney, M; Conibear, T; Johnson, M A; Haque, T; Webster, D P

2013-10-01

Studies have shown that low-frequency resistance mutations can influence treatment outcome. However, the lack of a standardized high-throughput assay has precluded their detection in clinical settings. To evaluate the performance of the Roche prototype 454 UDS HIV-1 drug resistance assay (UDS assay) in a routine diagnostic laboratory. 50 plasma samples, previously characterized by population sequencing and that had shown ≥1 resistance associated mutation (RAM), were retrospectively tested by the UDS assay, including 18 B and 32 non-B subtypes; viral loads between 114-1,806,407 cp/ml; drug-naive (n=27) and drug-experienced (n=23) individuals. The UDS assay was successful for 37/50 (74%) samples. It detected all RAMs found by population sequencing at frequencies above 20%. In addition, 39 low-frequency RAMs were exclusively detected by the UDS assay at frequencies below 20% in both drug-naïve (19/26, 73%) and drug-experienced (9/18, 50%) individuals. UDS results would lead to changes from susceptible to resistant to efavirenz (EFV) in one drug-naive individual with suboptimal response to an EFV-containing regimen and from susceptible to resistance to lamivudine (3TC) in one drug naïve subject who subsequently failed a 3TC-containing regimen and in a treatment experienced subject who had failed a 3TC-containing regimen. The UDS assay performed well across a wide range of subtypes and viral loads; it showed perfect agreement with population sequencing for all RAMs analyzed. In addition, the UDS assay detected additional mutations at frequencies below 20% which correlate with patients' treatment history and had in some cases important prognostic implications. Copyright © 2013 Elsevier B.V. All rights reserved.

Evolution of Cataclysmic Variables and Related Binaries Containing a White Dwarf

NASA Astrophysics Data System (ADS)

Kalomeni, B.; Nelson, L.; Rappaport, S.; Molnar, M.; Quintin, J.; Yakut, K.

2016-12-01

We present a binary evolution study of cataclysmic variables (CVs) and related systems with white dwarf (WD) accretors, including for example, AM CVn systems, classical novae, supersoft X-ray sources (SXSs), and systems with giant donor stars. Our approach intentionally avoids the complications associated with population synthesis algorithms, thereby allowing us to present the first truly comprehensive exploration of all of the subsequent binary evolution pathways that zero-age CVs might follow (assuming fully non-conservative, Roche-lobe overflow onto an accreting WD) using the sophisticated binary stellar evolution code MESA. The grid consists of 56,000 initial models, including 14 WD accretor masses, 43 donor-star masses (0.1-4.7 M ⊙), and 100 orbital periods. We explore evolution tracks in the orbital period and donor-mass (P orb-M don) plane in terms of evolution dwell times, masses of the WD accretor, accretion rate, and chemical composition of the center and surface of the donor star. We report on the differences among the standard CV tracks, those with giant donor stars, and ultrashort period systems. We show where in parameter space one can expect to find SXSs, present a diagnostic to distinguish among different evolutionary paths to forming AM CVn binaries, quantify how the minimum orbital period in CVs depends on the chemical composition of the donor star, and update the P orb(M wd) relation for binaries containing WDs whose progenitors lost their envelopes via stable Roche-lobe overflow. Finally, we indicate where in the P orb-M don the accretion disks will tend to be stable against the thermal-viscous instability, and where gravitational radiation signatures may be found with LISA.

Rms-flux relation and fast optical variability simulations of the nova-like system MV Lyr

NASA Astrophysics Data System (ADS)

Dobrotka, A.; Mineshige, S.; Ness, J.-U.

2015-03-01

The stochastic variability (flickering) of the nova-like system (subclass of cataclysmic variable) MV Lyr yields a complicated power density spectrum with four break frequencies. Scaringi et al. analysed high-cadence Kepler data of MV Lyr, taken almost continuously over 600 d, giving the unique opportunity to study multicomponent Power Density Spectra (PDS) over a wide frequency range. We modelled this variability with our statistical model based on disc angular momentum transport via discrete turbulent bodies with an exponential distribution of the dimension scale. Two different models were used, a full disc (developed from the white dwarf to the outer radius of ˜1010 cm) and a radially thin disc (a ring at a distance of ˜1010 cm from the white dwarf) that imitates an outer disc rim. We succeed in explaining the two lowest observed break frequencies assuming typical values for a disc radius of 0.5 and 0.9 times the primary Roche lobe and an α parameter of 0.1-0.4. The highest observed break frequency was also modelled, but with a rather small accretion disc with a radius of 0.3 times the primary Roche lobe and a high α value of 0.9 consistent with previous findings by Scaringi. Furthermore, the simulated light curves exhibit the typical linear rms-flux proportionality linear relation and the typical log-normal flux distribution. As the turbulent process is generating fluctuations in mass accretion that propagate through the disc, this confirms the general knowledge that the typical rms-flux relation is mainly generated by these fluctuations. In general, a higher rms is generated by a larger amount of superposed flares which is compatible with a higher mass accretion rate expressed by a larger flux.

Continuous glucose monitoring in newborn infants: how do errors in calibration measurements affect detected hypoglycemia?

PubMed

Thomas, Felicity; Signal, Mathew; Harris, Deborah L; Weston, Philip J; Harding, Jane E; Shaw, Geoffrey M; Chase, J Geoffrey

2014-05-01

Neonatal hypoglycemia is common and can cause serious brain injury. Continuous glucose monitoring (CGM) could improve hypoglycemia detection, while reducing blood glucose (BG) measurements. Calibration algorithms use BG measurements to convert sensor signals into CGM data. Thus, inaccuracies in calibration BG measurements directly affect CGM values and any metrics calculated from them. The aim was to quantify the effect of timing delays and calibration BG measurement errors on hypoglycemia metrics in newborn infants. Data from 155 babies were used. Two timing and 3 BG meter error models (Abbott Optium Xceed, Roche Accu-Chek Inform II, Nova Statstrip) were created using empirical data. Monte-Carlo methods were employed, and each simulation was run 1000 times. Each set of patient data in each simulation had randomly selected timing and/or measurement error added to BG measurements before CGM data were calibrated. The number of hypoglycemic events, duration of hypoglycemia, and hypoglycemic index were then calculated using the CGM data and compared to baseline values. Timing error alone had little effect on hypoglycemia metrics, but measurement error caused substantial variation. Abbott results underreported the number of hypoglycemic events by up to 8 and Roche overreported by up to 4 where the original number reported was 2. Nova results were closest to baseline. Similar trends were observed in the other hypoglycemia metrics. Errors in blood glucose concentration measurements used for calibration of CGM devices can have a clinically important impact on detection of hypoglycemia. If CGM devices are going to be used for assessing hypoglycemia it is important to understand of the impact of these errors on CGM data. © 2014 Diabetes Technology Society.

Associated liver enzymes with hyperlipidemic profile in type 2 diabetes patients.

PubMed

Al-Jameil, Noura; Khan, Farah A; Arjumand, Sadia; Khan, Mohammad F; Tabassum, Hajera

2014-01-01

Type 2 diabetes mellitus (T2DM) is characterized by hyperglycemia and is associated with dyslipidemia and disturbed liver function. Aim of the present work is to assess the liver enzymes and to find its association with hyperlipidemic profile in T2DM. Total of 157 subjects were studied and divided into two groups; diabetes (n=81) and non-diabetes (n=76). Various biochemical parameters like fasting glucose, post prandial glucose, HbA1c, total cholesterol (TC), triglycerides (Tg), high density lipoprotein cholesterol (HDL-C), alanine amino transferase (ALT), aspartate amino transferase (AST) and gamma-glutamyl transferase (GGT) were analyzed by ROCHE module Cobas 6000 (C501 & C601) analyzer, kits were procured by ROCHE diagnostics. Low density lipoprotein cholesterol (LDL-C) was estimated by Freidwald's formula. Statistical analysis was performed by applying student t test and Pearson's correlation coefficient, at 0.0001 and 0.05 level of significance, respectively. All the glycemic control parameters, lipid profile parameters except HDL-C and liver enzymes were found increased in diabetes group and significantly differ from non-diabetes group (p>0.0001). ALT showed significant positive correlation with fasting glucose, post prandial glucose, HbA1c, TC, Tg, LDL-C and GGT at p>0.05. AST showed very weak relation with all parameters while GGT was positively associated with fasting glucose, post prandial glucose, HbA1c, TC, Tg, LDL-C and ALT at p>0.05. In conclusion, T2DM incline to elevate liver enzymes, especially ALT and GGT were of significance. Routine screening of ALT and GGT in T2DM patients may assists early detection of liver abnormalities and to arrest the progress of disease.

Evaluation of the Roche LightMix Gastro parasites multiplex PCR assay detecting Giardia duodenalis, Entamoeba histolytica, cryptosporidia, Dientamoeba fragilis, and Blastocystis hominis.

PubMed

Friesen, J; Fuhrmann, J; Kietzmann, H; Tannich, E; Müller, M; Ignatius, R

2018-03-23

Multiplex PCR assays offer highly sensitive and specific tools for the detection of enteric pathogens. This prospective study aimed at comparing the novel Roche LightMix Modular Assay Gastro Parasites (LMAGP) detecting Giardia duodenalis, Entamoeba histolytica, Cryptosporidium spp., Blastocystishominis, and Dientamoebafragilis with routine laboratory procedures. Stool specimens (n = 1062 from 1009 patients) were consecutively examined by LMAGP, R-Biopharm Ridascreen enzyme immunoassays (EIAs) detecting G. duodenalis or E. histolytica/dispar, and microscopy of wet mounts. Discrepant results were analysed by in-house PCR. D. fragilis or B. hominis were detected by LMAGP in 131 (14.4%) and 179 (19.9%; 16 samples positive by microscopy; p < 0.0001) of 909 samples, respectively. Of 918 samples analysed for Cryptosporidium spp., six were positive by LMAGP (three could be confirmed by Kinyoun staining and one by in-house PCR). G. duodenalis was detected by LMAGP, EIA, or microscopy in 20, 16, or 9 of 1039 stool samples, respectively; all four samples missed by EIA were confirmed by in-house PCR. In total, 938 stool samples were analysed for E. histolytica/dispar. Nine of ten EIA-positive samples were negative by LMAGP but positive by in-house PCR for E. dispar. One E. histolytica infection (positive by both LMAGP and in-house PCR) was missed by EIA and microscopy. Parasites only detected by microscopy included Enterobius vermicularis eggs (n = 3) and apathogenic amoebae (n = 27). The data call for routine use of multiplex PCR assays for the detection of enteric protozoan parasites in laboratory diagnostics. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Laboratory blood analysis in Strigiformes-Part II: plasma biochemistry reference intervals and agreement between the Abaxis Vetscan V2 and the Roche Cobas c501.

PubMed

Ammersbach, Mélanie; Beaufrère, Hugues; Gionet Rollick, Annick; Tully, Thomas

2015-03-01

Limited plasma biochemical information is available in Strigiformes. Only one study investigated the agreement between a point-of-care with a reference laboratory analyzer for biochemistry variables in birds. The objective was to report reference intervals (RI) for plasma biochemistry variables in Strigiformes, and to assess agreement between the Abaxis Vetscan V2 and Roche Cobas c501. A prospective study was designed to assess plasma biochemistry RI for concentration of calcium, phosphorus, total protein, albumin, globulin, glucose, bilirubin, uric acid, bile acids, sodium, potassium, and chloride, and activities of AST, GGT, CK, amylase, lipase, LDH, and GLDH. In addition, the agreement between the Vetscan and the Cobas in owl species was assessed. A total of 190 individuals were sampled belonging to 12 Strigiformes species including Barn Owls, Barred Owls, Great Horned Owls, Eurasian Eagle Owls, Spectacled Owls, Eastern Screech Owls, Long-Eared Owls, Short-Eared Owls, Great Gray Owls, Snowy Owls, Northern Saw-Whet Owls, and Northern Hawk-Owls. Order-, species-, and method-specific RI were determined on both analyzers. Although Vetscan data were not equivalent to the Cobas, 4 analytes (glucose, AST, CK, and total protein, with correction for bias) were within acceptable agreement, 3 analytes (uric acid, calcium, and phosphorus) were within close agreement, and the remaining analytes were in strong disagreement. Species-specific differences were observed notably for the concentration of glucose in Barn Owls and electrolytes in Northern Saw-Whet Owls. Overall, this study suggests that the Vetscan has acceptable clinical performance in Strigiformes for some analytes and highlights discrepancies for several analytes. © 2015 American Society for Veterinary Clinical Pathology.

[Contribution of the laboratory in hypoglycemia diagnosis induced by insulin administration in a 2-year-old girl].

PubMed

Dejoie, T; Ramos, E; Baron, S; Bach-Ngohou, K; Masson, D

2008-01-01

We report the case of a 2 year-old child presented to the emergency department following a seizure. The child was hypotonic and examination was unremarkable but laboratory tests confirmed a severe hypoglycaemia. The insulin level, inappropriately high for the glycemia and the peptide C undetectable suggested exogenous hyperinsulinism. We conclude that the hypoglycaemia was likely the result of Munchhausen syndrome by proxy. The specificity of two immunoassays used (Elecsys Roche and IRMA CisBio) for the synthetic analogues of insulin explains the discrepancy between the insulin levels obtained but was crucially useful to the approach of the cause of the hypoglycaemia.

[Cutaneous melanoma - "black death" of modern times? Traces in contemporary literature].

PubMed

Bahmer, F A; Bahmer, J A

2013-11-01

Cutaneous melanoma, sometimes labeled as "black skin cancer", is increasing in frequency and becoming a more common literary motive. In US literature, Sylvia Plath and Charles Bukowski depicted melanoma more than 50 years ago, later Stephen King and Thomas C. Boyle. In German literature, Charlotte Roche shortly mentioned this tumor. Jörg Pönnighaus, both poet and dermatologist, intensively deals in his poems with the effects melanoma has on patients and doctors alike. Melanoma definitely is not the "Black Death" of modern times. However, the perception of this tumor as extremely malignant and as life-threatening makes melanoma a metaphor of the deadly danger of cancer.

Fault Tolerant Design Concepts for Highly Integrated Flight Critical Guidance and Control Systems: Conference Proceedings Held at the Guidance and Control Panel Symposium (49th) Held in Toulouse, France on 10-13 October 1989

DTIC Science & Technology

1990-04-01

conception des postes de pilotage et les r6les des pilotes doivent itre difinis avec soin en face des tiches automatis6es ainsi que les pcifications de...from USA and Canada: Commandant M.Mouhamad. FAF AGARD-NATO Executive, GCP Attention : GCP Executive AGARD-OTAN APO New York 09777 7 rue Ancelle F-92200...G.Manfeld 54 UN SYSTEME DE REFERENCES PRIMAIRES DE HAUTE INTEGRITE (A High Integrity Flight Data System) par J.L.Roch et J.Contet 55 ..... 4- K- ’-I

How Zantac became the best-selling drug in history.

PubMed

Wright, R

1996-01-01

Glaxo's Zantac began its dominance of the acid/peptic marketplace with a launch strategy, taking advantage of the established Roche sales force to rapidly promote the product. Educational symposia for physicians were instrumental in disseminating both disease and product information to primary care physicians and specialists. This technique not only pleased physicians (more referrals), but also increased public awareness of gastrointestinal disease, further expanding the patient market. Several novel marketing strategies contributed to Zantac's success, including the public-service announcements, celebrity media tours, and consumer-awareness bulletins, which brought the drug to the lay public and encouraged individuals to seek advice from their physicians.

LongISLND: in silico sequencing of lengthy and noisy datatypes

PubMed Central

Lau, Bayo; Mohiyuddin, Marghoob; Mu, John C.; Fang, Li Tai; Bani Asadi, Narges; Dallett, Carolina; Lam, Hugo Y. K.

2016-01-01

Summary: LongISLND is a software package designed to simulate sequencing data according to the characteristics of third generation, single-molecule sequencing technologies. The general software architecture is easily extendable, as demonstrated by the emulation of Pacific Biosciences (PacBio) multi-pass sequencing with P5 and P6 chemistries, producing data in FASTQ, H5, and the latest PacBio BAM format. We demonstrate its utility by downstream processing with consensus building and variant calling. Availability and Implementation: LongISLND is implemented in Java and available at http://bioinform.github.io/longislnd Contact: hugo.lam@roche.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27667791

Spectroscopic orbits of symbiotic stars - Preliminary results

NASA Technical Reports Server (NTRS)

Garcia, M. R.

1986-01-01

The present search for radial velocity variations due to orbital motions in symbiotic stars involved observations of 17 such stars at approximately 1-month intervals, as well as of radial velocity variations in the M-giant primary in nine stars. The observed radial velocity curves are commensurate with those expected from a group of binaries having random sin i and about 20 km/sec orbital velocities. Four of the orbital periods thus suggested for seven stars confirm previously known photometric periods, while one confirms a previously known orbital period and two are completely new. Knowledge of the orbits allows identification of those symbiotics that are close to filling their Roche lobes.

Active and realistic passive marijuana exposure tested by three immunoassays and GC/MS in urine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mule, S.J.; Lomax, P.; Gross, S.J.

Human urine samples obtained before and after active and passive exposure to marijuana were analyzed by immune kits (Roche, Amersham, and Syva) and gas chromatography/mass spectrometry (GC/MS). Seven of eight subjects were positive for the entire five-day test period with one immune kit. The latter correlated with GC/MS in 98% of the samples. Passive inhalation experiments under conditions likely to reflect realistic exposure resulted consistently in less than 10 ng/mL of cannabinoids. The 10-100-ng/mL cannabinoid concentration range essential for detection of occasional and moderate marijuana users is thus unaffected by realistic passive inhalation.

[Detection of Staphylococcus aureus resistant to methicillin (MRSA) by molecular biology (Cepheid GeneXpert IL, GeneOhm BD, Roche LightCycler, Hyplex Evigene I2A) versus screening by culture: Economic and practical strategy for the laboratory].

PubMed

Laudat, P; Demondion, E; Jouannet, C; Charron, J; Chillou, C; Salaun, V; Mankikian, B

2012-06-01

Patients admitted in cardiac surgery and cardiac ICU at the Clinic Saint-Gatien (Tours) are screened for MRSA at the entrance by nasal swab and culture on blood agar and selective chromogenic medium made by addition of cefoxitin: BBL CHROMagar MRSA-II BD (result obtained at Day +1). We wanted to assess the molecular biology techniques available to obtain a result at day 0 for the majority of patients and to define an economic and practical strategy for the laboratory. We studied four molecular biology techniques: Cepheid GeneXpert (Cepheid) GeneOhm (BD), LightCycler (Roche) and Hyplex (I2A). Upon reception, nasal swabs were treated by culture, considered as reference, and one of the techniques of molecular biology, according to the manufacturer's notice. We conducted four studies between April 2008 and February 2009 to obtain a significant sample for each of them. By screening we mean a method that allows us to exclude MRSA carriage for patients waiting for surgery, and not to change patient management: for example, lack of isolation measures specific to entrance, no modification of antibiotic prophylaxis during surgery and no isolation measures in the immediate postoperative period. The criteria we considered for this evaluation were: (1) technician time: time to perform one or a series of sample(s) n=10 or more (about 2h for all techniques except GeneXpert 75min), level of skilled competences (no specific training for GeneXpert); (2) results: turnaround time (all molecular biology techniques), ease of reading and results interpretations (no specialized training required for GeneXpert), failure or not (12% of failure of internal controls for GeneOhm); (3) economic: cost for one or a series of sample(s) (n=10 or more), if we considered X as the reference culture cost (10 X Hyplex and LightCycler, 20 X and 40 X for GeneXpert GeneOhm); (4) NPV: 100% for GeneXpert and LightCycler. At same sensitivity, no technique, including culture, can solve alone our problem, which is: (1) get results at day 0 for batch of samples (n<10): all molecular biology techniques; (2) beyond 10 samples: LightCycler (Roche) automated or Hyplex (I2A) manual; (3) when the result at day 1 is sufficient, the use of chromogenic agar with a reading of less than 18h as BBL CHROMagar MRSA II (BD) remains the most economical; (4) to be sure that a patient admitted at Day 0, even at night's emergency, is not carrier of MRSA: only Cepheid GeneXpert technology (IL). Furthermore, Cepheid GeneXpert (IL) allows performing several tests in parallel. The rapidity of this system can help control the transmission and make better use of antibiotics. Copyright © 2011 Elsevier Masson SAS. All rights reserved.