Precise alignment of the collection fiber assisted by real-time plasma imaging in laser-induced breakdown spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Motto-Ros, V., E-mail: vincent.motto-ros@univ-lyon1.fr [Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex (France); Negre, E. [Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex (France); CRITT Matériaux Alsace, 19, rue de St Junien, 67305 Schiltigheim (France); Pelascini, F. [CRITT Matériaux Alsace, 19, rue de St Junien, 67305 Schiltigheim (France); Panczer, G.; Yu, J. [Institut Lumière Matière, UMR 5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex (France)

2014-02-01

Improving the repeatability and the reproducibility of measurement with laser-induced breakdown spectroscopy (LIBS) is one of the actual challenging issues faced by the technique to fit the requirements of precise and accurate quantitative analysis. Among the numerous factors influencing the measurement stability in short and long terms, there are shot-to-shot and day-to-day fluctuations of the morphology of the plasma. Such fluctuations are due to the high sensitivity of laser-induced plasma to experimental conditions including properties of the sample, the laser parameters as well as properties of the ambient gas. In this paper, we demonstrate that precise alignment of the optical fiber for the collection of the plasma emission with respect to the actual morphology of the plasma assisted by real-time imaging, greatly improves the stability of LIBS measurements in short as well as in long terms. The used setup is based on a plasma imaging arrangement using a CCD camera and a real-time image processing. The obtained plasma image is displayed in a 2-dimensional frame where the position of the optical fiber is beforehand calibrated. In addition, the setup provides direct sample surface monitoring, which allows a precise control of the distance between the focusing lens and the sample surface. Test runs with a set of 8 reference samples show very high determination coefficient for calibration curves (R{sup 2} = 0.9999), and a long term repeatability and reproducibility of 4.6% (relative standard deviation) over a period of 3 months without any signal normalization. The capacity of the system to automatically correct the sample surface position for a tilted or non-regular sample surface during a surface mapping measurement is also demonstrated. - Highlights: • Automated alignment of the collection fiber by real-time plasma imaging • High level control of experimental parameters in LIBS experiments • Improvement of the short and long term stability in LIBS

Precise alignment of the collection fiber assisted by real-time plasma imaging in laser-induced breakdown spectroscopy

International Nuclear Information System (INIS)

Motto-Ros, V.; Negre, E.; Pelascini, F.; Panczer, G.; Yu, J.

2014-01-01

Improving the repeatability and the reproducibility of measurement with laser-induced breakdown spectroscopy (LIBS) is one of the actual challenging issues faced by the technique to fit the requirements of precise and accurate quantitative analysis. Among the numerous factors influencing the measurement stability in short and long terms, there are shot-to-shot and day-to-day fluctuations of the morphology of the plasma. Such fluctuations are due to the high sensitivity of laser-induced plasma to experimental conditions including properties of the sample, the laser parameters as well as properties of the ambient gas. In this paper, we demonstrate that precise alignment of the optical fiber for the collection of the plasma emission with respect to the actual morphology of the plasma assisted by real-time imaging, greatly improves the stability of LIBS measurements in short as well as in long terms. The used setup is based on a plasma imaging arrangement using a CCD camera and a real-time image processing. The obtained plasma image is displayed in a 2-dimensional frame where the position of the optical fiber is beforehand calibrated. In addition, the setup provides direct sample surface monitoring, which allows a precise control of the distance between the focusing lens and the sample surface. Test runs with a set of 8 reference samples show very high determination coefficient for calibration curves (R 2 = 0.9999), and a long term repeatability and reproducibility of 4.6% (relative standard deviation) over a period of 3 months without any signal normalization. The capacity of the system to automatically correct the sample surface position for a tilted or non-regular sample surface during a surface mapping measurement is also demonstrated. - Highlights: • Automated alignment of the collection fiber by real-time plasma imaging • High level control of experimental parameters in LIBS experiments • Improvement of the short and long term stability in LIBS measurements

Effect of sampling site, repeated sampling, pH, and PCO2 on plasma lactate concentration in healthy dogs.

Science.gov (United States)

Hughes, D; Rozanski, E R; Shofer, F S; Laster, L L; Drobatz, K J

1999-04-01

To characterize the variation in plasma lactate concentration among samples from commonly used blood sampling sites in conscious, healthy dogs. 60 healthy dogs. Cross-sectional study using a replicated Latin square design. Each dog was assigned to 1 of 6 groups (n = 10) representing all possible orders for 3 sites (cephalic vein, jugular vein, and femoral artery) used to obtain blood. Samples were analyzed immediately, by use of direct amperometry for pH, PO2, Pco2, glucose, and lactate concentration. Significant differences in plasma lactate concentrations were detected among blood samples from the cephalic vein (highest), femoral artery, and jugular vein (lowest). Mean plasma lactate concentration in the first sample obtained, irrespective of sampling site, was lower than in subsequent samples. Covariation was identified among plasma lactate concentration, pH, and PCO2, but correlation coefficients were low. Plasma lactate concentrations differed among blood samples from various sites. A reference range for plasma lactate concentration was 0.3 to 2.5 mmol/L. Differences in plasma lactate concentrations among samples from various sites and with repeated sampling, in healthy dogs, are small. Use of the reference range may facilitate the clinical use of plasma lactate concentration in dogs.

51Cr-EDTA plasma clearance in severe renal failure determined by one plasma sample

DEFF Research Database (Denmark)

Kamper, A L; Nielsen, S L

1989-01-01

Two hundred and thirty-four measurements of standard 51Cr-EDTA plasma clearance were made in 50 patients with severe chronic renal failure. Based on these data two calculation methods were attempted using one plasma sample drawn 24 h after injection of 51Cr-EDTA. One of the methods used the 'one...... at zero-time was derived from injected dose and body surface area. This method might provide values 1.5 ml/min below or 0.8 ml/min above the established method of 51Cr-EDTA plasma clearance, which would be acceptable for clinical purposes. It is concluded that exact plasma clearance of 51Cr-EDTA in severe...... renal dysfunction (estimated clearance values below 21 ml/min) may be determined with adequate precision by one plasma sample drawn at 24 h after injection of the tracer without sampling at 5 h. This appears to be a very practical simplification....

Collective plasma corrections to thermonuclear reactions rates in dense plasmas

International Nuclear Information System (INIS)

Tsytovich, V.N.

2002-01-01

General kinetic equations for nuclear reaction in dense plasmas are obtained. They take into account the first order collective plasma effects. Together with previously known corrections proportional to Z i Z j , the product of the charges Z i and Z j of two interacting nuclei, it is shown that there exist corrections proportional to the squares Z i 2 and Z j 2 of the charges. It is shown that the Salpeter's [1] correction due to the plasma screening of the interaction potential is at least r/d smaller (r is the nuclei size and d is Debye screening length) than previously thought and is zero in the approximation when the terms of the order r/d are neglected. But the correlation effects in the first approximation in the parameter 1/N d (where N d is the number of particle in the Debye sphere) give corrections which often coincide with the first order Salpeter's corrections (found by expansion in another small parameter, the ratio of thermal energy to Gamov's energy). The correlation corrections are ∝ Z i Z j , have a different physical meaning than the corrections [1], can have a different sign and are present for reactions where the Salpeter's corrections are zero. Previously in astrophysical applications it was widely used the interpolation formulas between weak and strong Salpeter's screening corrections. Since the correlation correction take place the previously known Salpeter's corrections and the strong correlation corrections is difficult to describe analytically, the interpolation formulas between the weak and strong correlations cannot be yet found. A new type of corrections are found here which are proportional to the square of the charges. They are due to collective change in electrostatic self-energy of the plasma system during the nuclear reactions. The latter corrections are found by taking into account the changes of plasma particle fluctuations by the nuclear reactions. Numerical evaluation of the plasma corrections for the nuclear reactions of the

First comparative analysis concerning the plasma platelet contamination during MNC collection.

Science.gov (United States)

Pfeiffer, Hella; Achenbach, Susanne; Strobel, Julian; Zimmermann, Robert; Eckstein, Reinhold; Strasser, Erwin F

2017-08-01

Monocytes can be cultured into dendritic cells with addition of autologous plasma, which is highly prone to platelet contamination due to the apheresis process. Since platelets affect the maturation process of monocytes into dendritic cells and might even lead to a diminished harvest of dendritic cells, it is very important to reduce the platelet contamination. A new collection device (Spectra Optia) was analyzed, compared to two established devices (COM.TEC, Cobe Spectra) and evaluated regarding the potential generation of source plasma. Concurrent plasma collected during leukapheresis was analyzed for residual cell contamination in a prospective study with the new Spectra Optia apheresis device (n=24) and was compared with COM.TEC and Cobe Spectra data (retrospective analysis, n=72). Donor pre-donation counts of platelets were analyzed for their predictive value of contaminating PLTs in plasma harvests. The newest apheresis device showed the lowest residual platelet count of the collected concurrent plasma (median 3.50×10 9 /l) independent of pre-donation counts. The other two devices and sets had a higher platelet contamination. The contamination of the plasma with leukocytes was very low (only 2.0% were higher than 0.5×10 9 /l). This study showed a significant reduction of platelet contamination of the concurrent plasma collected with the new Spectra Optia device. This plasma product with low residual platelets and leukocytes might also be used as plasma for fractionation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Atto-second control of collective electron motion in plasmas

International Nuclear Information System (INIS)

Borot, Antonin; Malvache, Arnaud; Chen, Xiaowei; Jullien, Aurelie; Lopez-Martens, Rodrigo; Geindre, Jean-Paul; Audebert, Patrick; Mourou, Gerard; Quere, Fabien

2012-01-01

Today, light fields of controlled and measured waveform can be used to guide electron motion in atoms and molecules with atto-second precision. Here, we demonstrate atto-second control of collective electron motion in plasmas driven by extreme intensity (approximate to 10 18 W cm -2 ) light fields. Controlled few-cycle near-infrared waves are tightly focused at the interface between vacuum and a solid-density plasma, where they launch and guide sub-cycle motion of electrons from the plasma with characteristic energies in the multi-kilo-electron-volt range-two orders of magnitude more than has been achieved so far in atoms and molecules. The basic spectroscopy of the coherent extreme ultraviolet radiation emerging from the light-plasma interaction allows us to probe this collective motion of charge with sub-200 as resolution. This is an important step towards atto-second control of charge dynamics in laser-driven plasma experiments. (authors)

Experimental breakdown of selected anodized aluminum samples in dilute plasmas

Science.gov (United States)

Grier, Norman T.; Domitz, Stanley

1992-01-01

Anodized aluminum samples representative of Space Station Freedom structural material were tested for electrical breakdown under space plasma conditions. In space, this potential arises across the insulating anodized coating when the spacecraft structure is driven to a negative bias relative to the external plasma potential due to plasma-surface interaction phenomena. For anodized materials used in the tests, it was found that breakdown voltage varied from 100 to 2000 volts depending on the sample. The current in the arcs depended on the sample, the capacitor, and the voltage. The level of the arc currents varied from 60 to 1000 amperes. The plasma number density varied from 3 x 10 exp 6 to 10 exp 3 ions per cc. The time between arcs increased as the number density was lowered. Corona testing of anodized samples revealed that samples with higher corona inception voltage had higher arcing inception voltages. From this it is concluded that corona testing may provide a method of screening the samples.

Immunoglobulin G levels during collection of large volume plasma for fractionation.

Science.gov (United States)

Burkhardt, Thomas; Rothe, Remo; Moog, Rainer

2017-06-01

There is a need of comprehensive work dealing with the quality of plasma for fractionation with respect to the IgG content as today most plasma derivates are used to treat patients with immunodeficiencies and autoimmune disorders. Therefore, a prospective study was carried out to analyse IgG levels before plasmapheresis and every 200ml collected plasma. Fifty-four experienced plasmapheresis donors were recruited for subsequent 850ml plasmapheresis using the Aurora Plasmapheresis System. Donorś peripheral blood counts were analysed before and after plasmapheresis using an electronic counter. Total protein, IgG and citrate were measured turbidometrically before, during and after apheresis as well as in the plasma product. Furthermore, platelets, red and white blood cells were analysed as parameters of product quality. An average of 2751±247ml blood was processed in 47±6min. The collected plasma volume was 850±1mL and citrate consumption was 177±15mL. A continuous drop of donors' IgG level was observed during plasmapheresis. The drop was 13% of the IgG baseline value at 800mL collected plasma. Total protein, IgG and cell counts of the plasma product met current guidelines of plasma for fractionation. Donors' IgG levels during apheresis showed a steady decrease without compromising the quality of plasma product. Copyright © 2017 Elsevier Ltd. All rights reserved.

High plasma corticosterone levels persist during frequent automatic blood sampling in rats

DEFF Research Database (Denmark)

Abelson, Klas S P; Adem, Bashir; Royo, Felix

2005-01-01

Corticosterone levels in blood may be used as a marker of stress in rodents, provided that the blood sampling procedure itself is non-stressful. Automated blood sampling equipment (Accusampler) allows blood sampling without any interference with the animal and might be useful as a tool for an on......-line measurement of stress markers in blood. However, the impact of the blood sampling itself on the corticosterone levels in blood is unknown. The present study was designed to evaluate whether the frequency of blood sampling influences the plasma corticosterone levels in male and female rats. During anaesthesia...... the importance of considering the frequency of blood withdrawal during automated blood sampling. This parameter may have an impact on the experimental results when using blood corticosterone levels as a stress marker, but also during any in vivo study where blood is collected, since high corticosterone levels...

Determination of organically bound Tritium in environmental samples by application of the oxidizing plasma technique

International Nuclear Information System (INIS)

Strack, S.; Koenig, L.A.

1981-12-01

The low-temperature oxidizing plasma technique with a suitable system for trapping the water formed in the oxidation process can be used to determine T bound organically in low-level samples. First, the samples are freeze-dried and the tissue water obtained in this way is measured, after distillation, in a liquid scintillation spectrometer. The residual dry matter is ashed in the reactor chamber of the plasma system. Oxidation takes place at temperatures not exceeding 200 0 C in an oxygen flow of about 40 ml/min. The water of oxidation is collected in a cold trap installed behind the reactor chamber. A volume of about 10 ml of water is sufficient to measure the tritium activity without enrichment. The oxidation behavior of various organic materials has been tested. Some first results of T concentrations in tissue water and the organic dry matter from food and plant samples collected in the vicinity of the Nuclear Research Center are presented. The method has the advantage that a commercially available instrument can be used requiring only little additional equipment. Handling is much less dangerous and contamination effects by atmospheric T can be easily kept at a minimum. (orig./HP) [de

Hybrid Plasma Reactor/Filter for Transportable Collective Protection Systems

Energy Technology Data Exchange (ETDEWEB)

Josephson, Gary B.; Tonkyn, Russell G.; Frye, J. G.; Riley, Brian J.; Rappe, Kenneth G.

2011-04-06

Pacific Northwest National Laboratory (PNNL) has performed an assessment of a Hybrid Plasma/Filter system as an alternative to conventional methods for collective protection. The key premise of the hybrid system is to couple a nonthermal plasma (NTP) reactor with reactive adsorption to provide a broader envelope of protection than can be provided through a single-solution approach. The first step uses highly reactive species (e.g. oxygen radicals, hydroxyl radicals, etc.) created in a nonthermal plasma (NTP) reactor to destroy the majority (~75% - 90%) of an incoming threat. Following the NTP reactor an O3 reactor/filter uses the O3 created in the NTP reactor to further destroy the remaining organic materials. This report summarizes the laboratory development of the Hybrid Plasma Reactor/Filter to protect against a ‘worst-case’ simulant, methyl bromide (CH3Br), and presents a preliminary engineering assessment of the technology to Joint Expeditionary Collective Protection performance specifications for chemical vapor air purification technologies.

Estimation of technetium 99m mercaptoacetyltriglycine plasma clearance by use of one single plasma sample

International Nuclear Information System (INIS)

Mueller-Suur, R.; Magnusson, G.; Karolinska Inst., Stockholm; Bois-Svensson, I.; Jansson, B.

1991-01-01

Recent studies have shown that technetium 99m mercaptoacetyltriglycine (MAG-3) is a suitable replacement for iodine 131 or 123 hippurate in gamma-camera renography. Also, the determination of its clearance is of value, since it correlates well with that of hippurate and thus may be an indirect measure of renal plasma flow. In order to simplify the clearance method we developed formulas for the estimation of plasma clearance of MAG-3 based on a single plasma sample and compared them with the multiple sample method based on 7 plasma samples. The correlation to effective renal plasma flow (ERPF) (according to Tauxe's method, using iodine 123 hippurate), which ranged from 75 to 654 ml/min per 1.73 m 2 , was determined in these patients. Using the developed regression equations the error of estimate for the simplified clearance method was acceptably low (18-14 ml/min), when the single plasma sample was taken 44-64 min post-injection. Formulas for different sampling times at 44, 48, 52, 56, 60 and 64 min are given, and we recommend 60 min as optimal, with an error of estimate of 15.5 ml/min. The correlation between the MAG-3 clearances and ERPF was high (r=0.90). Since normal values for MAG-3 clearance are not yet available, transformation to estimated ERPF values by the regression equation (ERPF=1.86xC MAG-3 +4.6) could be of clinical value in order to compare it with the normal values for ERPF given in the literature. (orig.)

Evaluating the optimum rest period prior to blood collection for fractionated plasma free metanephrines analysis

LENUS (Irish Health Repository)

Griffin, T.P.

2016-05-01

The high diagnostic accuracy of plasma metanephrines (PMets) in the di-agnosis of Phaeochromocytoma\\/Paraganglioma (PPGL) is well established. Considerable controversy exists regarding optimum sampling conditions for PMets. The use of reference intervals that do not compromise diagnostic sensitivity is recommended. However, the optimum rest period prior to sampling has yet to be clearly established. The aim of this study was to evaluate PMets concentrations in paired blood samples collected following 30 and 40 min seated-rest prior to sampling, in patients in whom it was clinically rea-sonable to suspect that PPGL may be present.

Effects of Long-Term Storage Time and Original Sampling Month on Biobank Plasma Protein Concentrations

Directory of Open Access Journals (Sweden)

Stefan Enroth

2016-10-01

Full Text Available The quality of clinical biobank samples is crucial to their value for life sciences research. A number of factors related to the collection and storage of samples may affect the biomolecular composition. We have studied the effect of long-time freezer storage, chronological age at sampling, season and month of the year and on the abundance levels of 108 proteins in 380 plasma samples collected from 106 Swedish women. Storage time affected 18 proteins and explained 4.8–34.9% of the observed variance. Chronological age at sample collection after adjustment for storage-time affected 70 proteins and explained 1.1–33.5% of the variance. Seasonal variation had an effect on 15 proteins and month (number of sun hours affected 36 proteins and explained up to 4.5% of the variance after adjustment for storage-time and age. The results show that freezer storage time and collection date (month and season exerted similar effect sizes as age on the protein abundance levels. This implies that information on the sample handling history, in particular storage time, should be regarded as equally prominent covariates as age or gender and need to be included in epidemiological studies involving protein levels.

Surface studies of plasma processed Nb samples

International Nuclear Information System (INIS)

Tyagi, Puneet V.; Doleans, Marc; Hannah, Brian S.; Afanador, Ralph; Stewart, Stephen; Mammosser, John; Howell, Matthew P; Saunders, Jeffrey W; Degraff, Brian D; Kim, Sang-Ho

2015-01-01

Contaminants present at top surface of superconducting radio frequency (SRF) cavities can act as field emitters and restrict the cavity accelerating gradient. A room temperature in-situ plasma processing technology for SRF cavities aiming to clean hydrocarbons from inner surface of cavities has been recently developed at the Spallation Neutron Source (SNS). Surface studies of the plasma-processed Nb samples by Secondary ion mass spectrometry (SIMS) and Scanning Kelvin Probe (SKP) showed that the NeO_2 plasma processing is very effective to remove carbonaceous contaminants from top surface and improves the surface work function by 0.5 to 1.0 eV.

Simple, miniaturized blood plasma extraction method.

Science.gov (United States)

Kim, Jin-Hee; Woenker, Timothy; Adamec, Jiri; Regnier, Fred E

2013-12-03

A rapid plasma extraction technology that collects a 2.5 μL aliquot of plasma within three minutes from a finger-stick derived drop of blood was evaluated. The utility of the plasma extraction cards used was that a paper collection disc bearing plasma was produced that could be air-dried in fifteen minutes and placed in a mailing envelop for transport to an analytical laboratory. This circumvents the need for venipuncture and blood collection in specialized vials by a phlebotomist along with centrifugation and refrigerated storage. Plasma extraction was achieved by applying a blood drop to a membrane stack through which plasma was drawn by capillary action. During the course of plasma migration to a collection disc at the bottom of the membrane stack blood cells were removed by a combination of adsorption and filtration. After the collection disc filled with an aliquot of plasma the upper membranes were stripped from the collection card and the collection disc was air-dried. Intercard differences in the volume of plasma collected varied approximately 1% while volume variations of less than 2% were seen with hematocrit levels ranging from 20% to 71%. Dried samples bearing metabolites and proteins were then extracted from the disc and analyzed. 25-Hydroxy vitamin D was quantified by LC-MS/MS analysis following derivatization with a secosteroid signal enhancing tag that imparted a permanent positive charge to the vitamin and reduced the limit of quantification (LOQ) to 1 pg of collected vitamin on the disc; comparable to values observed with liquid-liquid extraction (LLE) of a venipuncture sample. A similar study using conventional proteomics methods and spectral counting for quantification was conducted with yeast enolase added to serum as an internal standard. The LOQ with extracted serum samples for enolase was 1 μM, linear from 1 to 40 μM, the highest concentration examined. In all respects protein quantification with extracted serum samples was comparable to

Influence of collective nonideal shielding on fusion reaction in partially ionized classical nonideal plasmas

Science.gov (United States)

Lee, Myoung-Jae; Jung, Young-Dae

2017-04-01

The collective nonideal effects on the nuclear fusion reaction process are investigated in partially ionized classical nonideal hydrogen plasmas. The effective pseudopotential model taking into account the collective and plasma shielding effects is applied to describe the interaction potential in nonideal plasmas. The analytic expressions of the Sommerfeld parameter, the fusion penetration factor, and the cross section for the nuclear fusion reaction in nonideal plasmas are obtained as functions of the nonideality parameter, Debye length, and relative kinetic energy. It is found that the Sommerfeld parameter is suppressed due to the influence of collective nonideal shielding. However, the collective nonideal shielding is found to enhance the fusion penetration factor in partially ionized classical nonideal plasmas. It is also found that the fusion penetration factors in nonideal plasmas represented by the pseudopotential model are always greater than those in ideal plasmas represented by the Debye-Hückel model. In addition, it is shown that the collective nonideal shielding effect on the fusion penetration factor decreases with an increase of the kinetic energy.

Cracks and nanodroplets produced on tungsten surface samples by dense plasma jets

Science.gov (United States)

Ticoş, C. M.; Galaţanu, M.; Galaţanu, A.; Luculescu, C.; Scurtu, A.; Udrea, N.; Ticoş, D.; Dumitru, M.

2018-03-01

Small samples of 12.5 mm in diameter made from pure tungsten were exposed to a dense plasma jet produced by a coaxial plasma gun operated at 2 kJ. The surface of the samples was analyzed using a scanning electron microscope (SEM) before and after applying consecutive plasma shots. Cracks and craters were produced in the surface due to surface tensions during plasma heating. Nanodroplets and micron size droplets could be observed on the samples surface. An energy-dispersive spectroscopy (EDS) analysis revealed that the composition of these droplets coincided with that of the gun electrode material. Four types of samples were prepared by spark plasma sintering from powders with the average particle size ranging from 70 nanometers up to 80 μm. The plasma power load to the sample surface was estimated to be ≈4.7 MJ m-2 s-1/2 per shot. The electron temperature and density in the plasma jet had peak values 17 eV and 1.6 × 1022 m-3, respectively.

LC-MS analysis of the plasma metabolome–a novel sample preparation strategy

DEFF Research Database (Denmark)

Skov, Kasper; Hadrup, Niels; Smedsgaard, Jørn

2015-01-01

Blood plasma is a well-known body fluid often analyzed in studies on the effects of toxic compounds as physiological or chemical induced changes in the mammalian body are reflected in the plasma metabolome. Sample preparation prior to LC-MS based analysis of the plasma metabolome is a challenge...... as plasma contains compounds with very different properties. Besides, proteins, which usually are precipitated with organic solvent, phospholipids, are known to cause ion suppression in electrospray mass spectrometry. We have compared two different sample preparation techniques prior to LC-qTOF analysis...... of plasma samples: The first is protein precipitation; the second is protein precipitation followed by solid phase extraction with sub-fractionation into three sub-samples; a phospholipid, a lipid and a polar sub-fraction. Molecular feature extraction of the data files from LC-qTOF analysis of the samples...

Equipment for collecting samples of radioactive solutions

International Nuclear Information System (INIS)

Raggenbass, A.; Fradin, J.; Joubert, G.

1958-01-01

The authors present an equipment aimed at collecting samples of fission products to perform radio-chemical analysis. As the sample must have a total activity between 1 and 50 micro-Curie, this installation comprises a sampling system and a dilution device which aims at bringing the sample to the suitable activity. Samples are collected by means of needles. The sample reproducibility is discussed. The dilution device is described

Observations of non-collective x-ray scattering in warm dense carbon plasma

International Nuclear Information System (INIS)

Bao Lihua; Zhang Jiyan; Zhao Yang; Ding Yongkun; Zhang Xiaoding

2012-01-01

An experiment for observing the spectrally resolved non-collective x-ray scattering in warm dense carbon plasma is presented in this paper. The experiment used Ta M-band x-rays to heat a foamed carbon cylinder sample isochorically and measured the scattering spectrum with a HOPG crystal spectrometer. The spectrum was compared with the calculation results using a Born-Mermin-approximation model. The best fitting was found at an electron temperature of T e =34 eV and an electron density of n e =1.6×10 23 cm −3 .

The Quark-Gluon Plasma Collective Dynamics and Hard Thermal Loops

CERN Document Server

Blaizot, J P; Blaizot, Jean-Paul; Iancu, Edmond

2002-01-01

We present a unified description of the high temperature phase of QCD, the so-called quark-gluon plasma, in a regime where the effective gauge coupling $g$ is sufficiently small to allow for weak coupling calculations. The main focuss is the construction of the effective theory for the collective excitations which develop at a typical scale $gT$, which is well separated from the typical energy of single particle excitations which is the temperature $T$. We show that the plasma particles provide a source for long wavelength oscillations of average fields which carry the quantum numbers of the plasma constituents, the quarks and the gluons. To leading order in $g$, the plasma particles obey simple gauge-covariant kinetic equations, whose derivation from the general Dyson-Schwinger equations is outlined. As a by-product, the ``hard thermal loops'' emerge naturally in a physically transparent framework. We show that the collective excitations can be described in terms of classical fields, and develop for these a ...

Urine sample collection protocols for bioassay samples

Energy Technology Data Exchange (ETDEWEB)

MacLellan, J.A.; McFadden, K.M.

1992-11-01

In vitro radiobioassay analyses are used to measure the amount of radioactive material excreted by personnel exposed to the potential intake of radioactive material. The analytical results are then used with various metabolic models to estimate the amount of radioactive material in the subject`s body and the original intake of radioactive material. Proper application of these metabolic models requires knowledge of the excretion period. It is normal practice to design the bioassay program based on a 24-hour excretion sample. The Hanford bioassay program simulates a total 24-hour urine excretion sample with urine collection periods lasting from one-half hour before retiring to one-half hour after rising on two consecutive days. Urine passed during the specified periods is collected in three 1-L bottles. Because the daily excretion volume given in Publication 23 of the International Commission on Radiological Protection (ICRP 1975, p. 354) for Reference Man is 1.4 L, it was proposed to use only two 1-L bottles as a cost-saving measure. This raised the broader question of what should be the design capacity of a 24-hour urine sample kit.

Urine sample collection protocols for bioassay samples

Energy Technology Data Exchange (ETDEWEB)

MacLellan, J.A.; McFadden, K.M.

1992-11-01

In vitro radiobioassay analyses are used to measure the amount of radioactive material excreted by personnel exposed to the potential intake of radioactive material. The analytical results are then used with various metabolic models to estimate the amount of radioactive material in the subject's body and the original intake of radioactive material. Proper application of these metabolic models requires knowledge of the excretion period. It is normal practice to design the bioassay program based on a 24-hour excretion sample. The Hanford bioassay program simulates a total 24-hour urine excretion sample with urine collection periods lasting from one-half hour before retiring to one-half hour after rising on two consecutive days. Urine passed during the specified periods is collected in three 1-L bottles. Because the daily excretion volume given in Publication 23 of the International Commission on Radiological Protection (ICRP 1975, p. 354) for Reference Man is 1.4 L, it was proposed to use only two 1-L bottles as a cost-saving measure. This raised the broader question of what should be the design capacity of a 24-hour urine sample kit.

Polybrominated diphenyl ethers in paired samples of maternal and umbilical cord blood plasma and associations with house dust in a Danish cohort

DEFF Research Database (Denmark)

Frederiksen, Marie; Thomsen, Cathrine; Frøshaug, May

2010-01-01

determined in placental tissue from the same individuals, and the relationship with the external exposure from house dust from the participants' homes was explored. Samples of maternal and umbilical cord plasma from a cohort of 51 pregnant women from the Copenhagen area were collected. Paired maternal...... and umbilical cord plasma were analysed for BDE-28, 37, 47, 85, 99, 100, 119, 138, 153, 154, 183, 209 and the brominated biphenyl BB-153 using automated SPE extraction and GC-HRMS for the tri- to hepta-BDEs and GC-LRMS (ECNI) for BDE-209. PBDEs were detected in all maternal and umbilical cord plasma samples...

Genotoxicity studies in semiconductor industry. 1. In vitro mutagenicity and genotoxicity studies of waste samples resulting from plasma etching

Energy Technology Data Exchange (ETDEWEB)

Braun, R.; Huettner, E.M.; Merten, H.; Raabe, F. (Institute of Plant Genetics and Crop Plant Research, Gatersleben (Germany))

1993-07-01

Solid waste samples taken from the etching reactor, the turbo pump, and the waste air system of a plasma etching technology line in semiconductor production were studied as to their genotoxic properties in a bacterial repair test, in the Ames/Salmonella microsome assay, in the SOS chromotest, in primary mouse hepatocytes, and in Chinese hamster V79 cell cultures. All three waste samples were found to be active by inducing of unscheduled DNA-synthesis in mouse hepatocytes in vitro. In the bacterial rec-type repair test with Proteus mirabilis, waste samples taken from the turbo pump and the vacuum pipe system were not genotoxic. The waste sample taken from the chlorine-mediated plasma reactor was clearly positive in the bacterial repair assay and in the SOS chromotest with Escherichia coli. Mutagenic activity was demonstrated for all samples in the presence and absence of S9 mix made from mouse liver homogenate. Again, highest mutagenic activity was recorded for the waste sample taken from the plasma reactor, while samples collected from the turbo pump and from the waste air system before dilution and liberation of the air were less mutagenic. For all samples chromosomal damage in V79 cells was not detected, indicating absence of clastogenic activity in vitro. Altogether, these results indicate generation of genotoxic and mutagenic products as a consequence of chlorine-mediated plasma etching in the microelectronics industry and the presence of genotoxins even in places distant from the plasma reactor. Occupational exposure can be expected both from the precipitated wastes and from chemicals reaching the environment with the air stream.

28 CFR 28.12 - Collection of DNA samples.

Science.gov (United States)

2010-07-01

... Homeland Security, collecting DNA samples from: (1) Aliens lawfully in, or being processed for lawful... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Collection of DNA samples. 28.12 Section 28.12 Judicial Administration DEPARTMENT OF JUSTICE DNA IDENTIFICATION SYSTEM DNA Sample Collection...

IFCC guideline for sampling, measuring and reporting ionized magnesium in plasma

DEFF Research Database (Denmark)

Rayana, M.C. Ben; Burnett, R.W.; Covington, A.K.

2008-01-01

Analyzers with ion-selective electrodes (ISEs) for ionized magnesium (iMg) should yield comparable and unbiased results for iMg. This IFCC guideline on sampling, measuring and reporting iMg in plasma provides a prerequisite to achieve this goal [in this document, "plasma" refers to circulating...... plasma and the forms in which it is sampled, namely the plasma phase of anticoagulated whole blood (or "blood"), plasma separated from blood cells, or serum]. The guideline recommends measuring and reporting ionized magnesium as a substance concentration relative to the substance concentration...... of magnesium in primary aqueous calibrants with magnesium, sodium, and calcium chloride of physiological ionic strength. The recommended name is "the concentration of ionized magnesium in plasma". Based on this guideline, results will be approximately 3% higher than the true substance concentration and 4...

Collecting Ground Samples for Balloon-Borne Instruments

Science.gov (United States)

Jones, Jack; Zimmerman, Wayne; Wu, Jiunn Jenq

2009-01-01

A proposed system in a gondola containing scientific instruments suspended by a balloon over the surface of the Saturn moon Titan would quickly acquire samples of rock or ice from the ground below. Prototypes of a sample-collecting device that would be a major part of the system have been tested under cryogenic and non-cryogenic conditions on Earth. Systems like this one could also be used in non-cryogenic environments on Earth to collect samples of rock, soil, ice, mud, or other ground material from such inaccessible or hazardous locations as sites of suspected chemical spills or biological contamination. The sample-collecting device would be a harpoonlike device that would be connected to the balloon-borne gondola by a tether long enough to reach the ground. The device would be dropped from the gondola to acquire a sample, then would be reeled back up to the gondola, where the sample would be analyzed by the onboard instruments. Each prototype of the sample-collecting device has a sharp front (lower) end, a hollow core for retaining a sample, a spring for holding the sample in the hollow core, and a rear (upper) annular cavity for retaining liquid sample material. Aerodynamic fins at the rear help to keep the front end pointed downward. In tests, these prototype devices were dropped from various heights and used to gather samples of dry sand, moist sand, cryogenic water ice, and warmer water ice.

Untargeted metabolomic profiling plasma samples of patients with lung cancer for searching significant metabolites by HPLC-MS method

Science.gov (United States)

Dementeva, N.; Ivanova, K.; Kokova, D.; Kurzina, I.; Ponomaryova, A.; Kzhyshkowska, J.

2017-09-01

Lung cancer is one of the most common types of cancer leading to death. Consequently, the search and the identification of the metabolites associated with the risk of developing cancer are very valuable. For the purpose, untargeted metabolic profiling of the plasma samples collected from the patients with lung cancer (n = 100) and the control group (n = 100) was conducted. After sample preparation, the plasma samples were analyzed using LC-MS method. Biostatistics methods were applied to pre-process the data for elicitation of dominating metabolites which responded to the difference between the case and the control groups. At least seven significant metabolites were evaluated and annotated. The most part of identified metabolites are connected with lipid metabolism and their combination could be useful for follow-up studies of lung cancer pathogenesis.

Impurity flux collection at the plasma edge of the tokamak MT-1

International Nuclear Information System (INIS)

Hildebrandt, D.; Bakos, J.S.; Petravich, G.

1989-09-01

Fluxes of intrinsic and injected impurities and background plasma ions were collected using a bidirectional probe at the plasma edge of the tokamak MT-1. The directional and radial dependences of injected impurities and plasma ions were very similar indicating a strong coupling of the impurity transport to the dynamics of the background plasma. The measured intrinsic concentration of about 10 -4 for Mo at the plasma edge is derived. (author) 17 refs.; 5 figs

Excitation of collective plasma modes during collisions between dust grains and the formation of dust plasma crystals

International Nuclear Information System (INIS)

Goree, J.A.; Morfill, G.; Tsytovich, V.N.

1998-01-01

Dust plasma crystals have recently been produced in experiments in a number of laboratories. For dust crystallization to occur, there should exist an efficient mechanism for the cooling of the dust plasma component. It is shown that the excitation of collective plasma modes during collisions between the grains may serve as the required cooling mechanism. The excitation of dust sound waves is found to be most efficient. It is shown that the cooling of dust grains via the excitation of collective plasma modes can be even more efficient than that due to collisions with neutral particles, which was previously considered to be the only mechanism for cooling of the dust plasma component. At present, the first experiments are being carried out to study collisions between individual dust grains. High efficiency of the excitation of plasma modes caused by collisions between dust grains is attributed to the coherent displacement of the plasma particles that shield the grains. it is shown that the excitation efficiency is proportional to the fourth power of the charge of the dust grains and to a large power of their relative velocity, and is independent of their mass. The results obtained can be checked in experiments studying how the binary collisions between dust grains and the pressure of the neutral component influence the dust crystallization

Collective Thomson scattering capabilities to diagnose fusion plasmas

DEFF Research Database (Denmark)

Korsholm, Søren Bang; Bindslev, Henrik; Furtula, Vedran

2010-01-01

Collective Thomson scattering (CTS) is a versatile technique for diagnosing fusion plasmas. In particular, experiments on diagnosing the ion temperature and fast ion velocity distribution have been executed on a number of fusion devices. In this article the main aim is to describe the technique...

The Apollo lunar samples collection analysis and results

CERN Document Server

Young, Anthony

2017-01-01

This book focuses on the specific mission planning for lunar sample collection, the equipment used, and the analysis and findings concerning the samples at the Lunar Receiving Laboratory in Texas. Anthony Young documents the collection of Apollo samples for the first time for readers of all backgrounds, and includes interviews with many of those involved in planning and analyzing the samples. NASA contracted with the U.S. Geologic Survey to perform classroom and field training of the Apollo astronauts. NASA’s Geology Group within the Manned Spacecraft Center in Houston, Texas, helped to establish the goals of sample collection, as well as the design of sample collection tools, bags, and storage containers. In this book, detailed descriptions are given on the design of the lunar sampling tools, the Modular Experiment Transporter used on Apollo 14, and the specific areas of the Lunar Rover vehicle used for the Apollo 15, 16, and 17 missions, which carried the sampling tools, bags, and other related equipment ...

Comparison of glomerular filtration rate measured by plasma sample technique, Cockroft Gault method and Gates’ method in voluntary kidney donors and renal transplant recipients

International Nuclear Information System (INIS)

Hephzibah, Julie; Shanthly, Nylla; Oommen, Regi

2013-01-01

There are numerous methods for calculation of glomerular filtration rate (GFR), which is a crucial measurement to identify patients with renal disease. The aim of this study is to compare four different methods of GFR calculation. Clinical setup, prospective study. Data was collected from routine renal scans done for voluntary kidney donors (VKD) or renal transplant recipients 6 months after transplantation. Following technetium-99m diethylene triamine penta acetic acid injection, venous blood samples were collected from contralateral arm at 120, 180, and 240 min through an indwelling venous cannula and direct collection by syringe. A total volume of 1 ml of plasma from each sample and standards were counted in an automatic gamma counter for 1 min. Blood samples taken at 120 min and 240 min were used for double plasma sample method (DPSM) and a sample taken at 180 min for single plasma sample method (SPSM). Russell's formulae for SPSM and DPSM were used for GFR estimation. Gates’ method GFR was calculated by vendor provided software. Correlation analysis was performed using Pearson's correlation test. SPSM correlated well with DPSM. GFR value in healthy potential kidney donors has a significant role in the selection of donors. The mean GFR ± (standard deviation) in VKD using SPSM, DPSM, camera depth method and Cockroft Gault method was 134.6 (25.9), 137.5 (42.4), 98.6 (15.9), 83.5 (21.1) respectively. Gates’ GFR calculation did not correlate well with plasma sampling method. Calculation of GFR plays a vital role in the management of renal patients, hence it was noted that Gates GFR may not be a reliable method of calculation. SPSM was more reliable. DPSM is reliable but cumbersome. It is difficult to accurately calculate GFR without a gold standard

Influence of sexual stimulation on sperm parameters in semen samples collected via masturbation from normozoospermic men or cryptozoospermic men participating in an assisted reproduction programme.

Science.gov (United States)

Yamamoto, Y; Sofikitis, N; Mio, Y; Miyagawa, I

2000-05-01

To evaluate the influence of sexual stimulation via sexually stimulating videotaped visual images (VIM) on sperm function, two semen samples were collected from each of 19 normozoospermic men via masturbation with VIM. Two additional samples were collected from each man via masturbation without VIM. The volume of seminal plasma, total sperm count, sperm motility, percentage of morphologically normal spermatozoa, outcome of hypo-osmotic swelling test and zona-free hamster oocyte sperm penetration assay, and markers of the secretory function of prostate were significantly larger in semen samples collected via masturbation with VIM than masturbation without VIM. The improved sperm parameters in the samples collected via masturbation with VIM may reflect an enhanced prostatic secretory function and increased loading of the vas deferens at that time. In a similar protocol, two semen samples were collected via masturbation with VIM from each of 22 non-obstructed azoospermic men. Semen samples from these men had been occasionally positive in the past for a very small number of spermatozoa (cryptozoospermic men). Two additional samples were collected from each cryptozoospermic man via masturbation without VIM. The volume of seminal plasma, total sperm count, sperm motility, and a marker of the secretory function of prostate were significantly larger in semen samples collected via masturbation with VIM. Fourteen out of the 22 men were negative for spermatozoa in both samples collected via masturbation without VIM. These men demonstrated spermatozoa in both samples collected via masturbation with VIM. Six men with immotile spermatozoa in both samples collected via masturbation without VIM exposed motile spermatozoa in both samples collected via masturbation with VIM. High sexual stimulation during masturbation with VIM results in recovery of spermatozoa of greater fertilizing potential both in normozoospermic and cryptozoospermic men. The appearance of spermatozoa after

On-line Automated Sample Preparation-Capillary Gas Chromatography for the Analysis of Plasma Samples.

NARCIS (Netherlands)

Louter, A.J.H.; van der Wagt, R.A.C.A.; Brinkman, U.A.T.

1995-01-01

An automated sample preparation module, (the automated sample preparation with extraction columns, ASPEC), was interfaced with a capillary gas chromatograph (GC) by means of an on-column interface. The system was optimised for the determination of the antidepressant trazodone in plasma. The clean-up

Design and development of a highly sensitive, field portable plasma source instrument for on-line liquid stream monitoring and real-time sample analysis

International Nuclear Information System (INIS)

Duan, Yixiang; Su, Yongxuan; Jin, Zhe; Abeln, Stephen P.

2000-01-01

The development of a highly sensitive, field portable, low-powered instrument for on-site, real-time liquid waste stream monitoring is described in this article. A series of factors such as system sensitivity and portability, plasma source, sample introduction, desolvation system, power supply, and the instrument configuration, were carefully considered in the design of the portable instrument. A newly designed, miniature, modified microwave plasma source was selected as the emission source for spectroscopy measurement, and an integrated small spectrometer with a charge-coupled device detector was installed for signal processing and detection. An innovative beam collection system with optical fibers was designed and used for emission signal collection. Microwave plasma can be sustained with various gases at relatively low power, and it possesses high detection capabilities for both metal and nonmetal pollutants, making it desirable to use for on-site, real-time, liquid waste stream monitoring. An effective in situ sampling system was coupled with a high efficiency desolvation device for direct-sampling liquid samples into the plasma. A portable computer control system is used for data processing. The new, integrated instrument can be easily used for on-site, real-time monitoring in the field. The system possesses a series of advantages, including high sensitivity for metal and nonmetal elements; in situ sampling; compact structure; low cost; and ease of operation and handling. These advantages will significantly overcome the limitations of previous monitoring techniques and make great contributions to environmental restoration and monitoring. (c)

The development of a Martian atmospheric Sample collection canister

Science.gov (United States)

Kulczycki, E.; Galey, C.; Kennedy, B.; Budney, C.; Bame, D.; Van Schilfgaarde, R.; Aisen, N.; Townsend, J.; Younse, P.; Piacentine, J.

The collection of an atmospheric sample from Mars would provide significant insight to the understanding of the elemental composition and sub-surface out-gassing rates of noble gases. A team of engineers at the Jet Propulsion Laboratory (JPL), California Institute of Technology have developed an atmospheric sample collection canister for Martian application. The engineering strategy has two basic elements: first, to collect two separately sealed 50 cubic centimeter unpressurized atmospheric samples with minimal sensing and actuation in a self contained pressure vessel; and second, to package this atmospheric sample canister in such a way that it can be easily integrated into the orbiting sample capsule for collection and return to Earth. Sample collection and integrity are demonstrated by emulating the atmospheric collection portion of the Mars Sample Return mission on a compressed timeline. The test results achieved by varying the pressure inside of a thermal vacuum chamber while opening and closing the valve on the sample canister at Mars ambient pressure. A commercial off-the-shelf medical grade micro-valve is utilized in the first iteration of this design to enable rapid testing of the system. The valve has been independently leak tested at JPL to quantify and separate the leak rates associated with the canister. The results are factored in to an overall system design that quantifies mass, power, and sensing requirements for a Martian atmospheric Sample Collection (MASC) canister as outlined in the Mars Sample Return mission profile. Qualitative results include the selection of materials to minimize sample contamination, preliminary science requirements, priorities in sample composition, flight valve selection criteria, a storyboard from sample collection to loading in the orbiting sample capsule, and contributions to maintaining “ Earth” clean exterior surfaces on the orbiting sample capsule.

Ion sampling and transport in Inductively Coupled Plasma Mass Spectrometry

Science.gov (United States)

Farnsworth, Paul B.; Spencer, Ross L.

2017-08-01

Quantitative accuracy and high sensitivity in inductively coupled plasma mass spectrometry (ICP-MS) depend on consistent and efficient extraction and transport of analyte ions from an inductively coupled plasma to a mass analyzer, where they are sorted and detected. In this review we examine the fundamental physical processes that control ion sampling and transport in ICP-MS and compare the results of theory and computerized models with experimental efforts to characterize the flow of ions through plasma mass spectrometers' vacuum interfaces. We trace the flow of ions from their generation in the plasma, into the sampling cone, through the supersonic expansion in the first vacuum stage, through the skimmer, and into the ion optics that deliver the ions to the mass analyzer. At each stage we consider idealized behavior and departures from ideal behavior that affect the performance of ICP-MS as an analytical tool.

The U.S. Geological Survey Geologic Collections Management System (GCMS)—A master catalog and collections management plan for U.S. Geological Survey geologic samples and sample collections

Science.gov (United States)

,

2015-01-01

The U.S. Geological Survey (USGS) is widely recognized in the earth science community as possessing extensive collections of earth materials collected by research personnel over the course of its history. In 2006, a Geologic Collections Inventory was conducted within the USGS Geology Discipline to determine the extent and nature of its sample collections, and in 2008, a working group was convened by the USGS National Geologic and Geophysical Data Preservation Program to examine ways in which these collections could be coordinated, cataloged, and made available to researchers both inside and outside the USGS. The charge to this working group was to evaluate the proposition of creating a Geologic Collections Management System (GCMS), a centralized database that would (1) identify all existing USGS geologic collections, regardless of size, (2) create a virtual link among the collections, and (3) provide a way for scientists and other researchers to obtain access to the samples and data in which they are interested. Additionally, the group was instructed to develop criteria for evaluating current collections and to establish an operating plan and set of standard practices for handling, identifying, and managing future sample collections. Policies and procedures promoted by the GCMS would be based on extant best practices established by the National Science Foundation and the Smithsonian Institution. The resulting report—USGS Circular 1410, “The U.S. Geological Survey Geologic Collections Management System (GCMS): A Master Catalog and Collections Management Plan for U.S. Geological Survey Geologic Samples and Sample Collections”—has been developed for sample repositories to be a guide to establishing common practices in the collection, retention, and disposal of geologic research materials throughout the USGS.

Plasma rotation and ion temperature measurements by collective Thomson scattering at ASDEX Upgrade

DEFF Research Database (Denmark)

Stejner Pedersen, Morten; Nielsen, Stefan Kragh; Jacobsen, Asger Schou

2015-01-01

We present the first deuterium ion temperature and rotation measurements by collective Thomson scattering at ASDEX Upgrade. The results are in general agreement with boron-based charge exchange recombination spectroscopy measurements and consistent with neoclassical simulations for the plasma sce...... scenario studied here. This demonstration opens the prospect for direct non-perturbative measurements of the properties of the main ion species in the plasma core with applications in plasma transport and confinement studies.......We present the first deuterium ion temperature and rotation measurements by collective Thomson scattering at ASDEX Upgrade. The results are in general agreement with boron-based charge exchange recombination spectroscopy measurements and consistent with neoclassical simulations for the plasma...

Plasma androgen concentrations in initial samples from spotted ...

African Journals Online (AJOL)

1990-01-31

Jan 31, 1990 ... initial samples, the immobilization stress response and the response to exogenous GnRH administration, for ... the sex-specific differences in plasma androgens is confounded by other variables such as the reproductive.

Kinetic Analysis of Weakly ionized Plasmas in presence of collecting walls

Science.gov (United States)

Gonzalez, J.; Donoso, J. M.

2018-02-01

Description of plasmas in contact with a wall able to collecting or emitting charged particles is a research topic of great importance. This situation arises in a great variety of phenomena such as the characterization of plasmas by means of electric probes, in the surface treatment of materials and in the service-life of coatings in electric thrusters. In particular, in this work we devote attention to the dynamics of an argon weakly ionized plasma in the presence of a collecting wall. It is proposed a kinetic model in a 1D1V planar phase-space geometry. The model accounts for the electric field coupled to the system by solving the associated Poisson’s equation. To solve numerically the resulting non-linear system of equations, the Propagator Integral Method is used in conjunction with a slabbing method. On each interrelating plasma slab the integral advancing scheme operates in velocity space, in such a way that the all the species dynamics dominating the system evolution are kinetically described.

Biopolymers for sample collection, protection, and preservation.

Science.gov (United States)

Sorokulova, Iryna; Olsen, Eric; Vodyanoy, Vitaly

2015-07-01

One of the principal challenges in the collection of biological samples from air, water, and soil matrices is that the target agents are not stable enough to be transferred from the collection point to the laboratory of choice without experiencing significant degradation and loss of viability. At present, there is no method to transport biological samples over considerable distances safely, efficiently, and cost-effectively without the use of ice or refrigeration. Current techniques of protection and preservation of biological materials have serious drawbacks. Many known techniques of preservation cause structural damages, so that biological materials lose their structural integrity and viability. We review applications of a novel bacterial preservation process, which is nontoxic and water soluble and allows for the storage of samples without refrigeration. The method is capable of protecting the biological sample from the effects of environment for extended periods of time and then allows for the easy release of these collected biological materials from the protective medium without structural or DNA damage. Strategies for sample collection, preservation, and shipment of bacterial, viral samples are described. The water-soluble polymer is used to immobilize the biological material by replacing the water molecules within the sample with molecules of the biopolymer. The cured polymer results in a solid protective film that is stable to many organic solvents, but quickly removed by the application of the water-based solution. The process of immobilization does not require the use of any additives, accelerators, or plastifiers and does not involve high temperature or radiation to promote polymerization.

Self-modulation and anomalous collective scattering of laser produced intense ion beam in plasmas

Directory of Open Access Journals (Sweden)

K. Mima

2018-05-01

Full Text Available The collective interaction between intense ion beams and plasmas is studied by simulations and experiments, where an intense proton beam produced by a short pulse laser is injected into a pre-ionized gas. It is found that, depending on its current density, collective effects can significantly alter the propagated ion beam and the stopping power. The quantitative agreement that is found between theories and experiments constitutes the first validation of the collective interaction theory. The effects in the interaction between intense ion beams and background gas plasmas are of importance for the design of laser fusion reactors as well as for beam physics. Keywords: Two stream instabilities, Ultra intense short pulse laser, Proton beam, Wake field, Electron plasma wave, Laser plasma interaction, PACS codes: 52.38.Kd, 29.27.Fh, 52.40.Kh, 52.70.Nc

Comparison of measurement of 99mTc-MAG3 plasma clearance by single plasma sample and renal uptake ratio

International Nuclear Information System (INIS)

Ushijima, Yo; Sugihara, Hiroki; Okuyama, Chio; Okitsu, Sigeyuki; Nii, Takeshi; Nishida, Takuji; Okamoto, Kunio; Maeda, Tomoho

1997-01-01

Measurement of 99m Tc-MAG 3 plasma clearance based on one-compartment model (MPC method) is a non-invasive method using the renal uptake ratio. We evaluated the clinical usefulness of this method, compared with effective renal plasma flow (ERPF) using 123 I-OIH and two single-plasma sample methods using 99m Tc-MAG 3 (Russell method and Bubeck method). The ratio of 99m Tc-MAG 3 clearance to ERPF was 1.00±0.26. MPC method correlated well with Russell and Bubeck methods (r=0.904, r=0.897). We conclude that MPC method is a suitable replacement for single-plasma sample method in routine clinical use. (author)

Metabolic fingerprinting of high-fat plasma samples processed by centrifugation- and filtration-based protein precipitation delineates significant differences in metabolite information coverage.

Science.gov (United States)

Barri, Thaer; Holmer-Jensen, Jens; Hermansen, Kjeld; Dragsted, Lars O

2012-03-09

Metabolomics and metabolic fingerprinting are being extensively employed for improved understanding of biological changes induced by endogenous or exogenous factors. Blood serum or plasma samples are often employed for metabolomics studies. Plasma protein precipitation (PPP) is currently performed in most laboratories before LC-MS analysis. However, the impact of fat content in plasma samples on metabolite coverage has not previously been investigated. Here, we have studied whether PPP procedures influence coverage of plasma metabolites from high-fat plasma samples. An optimized UPLC-QTOF/MS metabolic fingerprinting approach and multivariate modeling (PCA and OPLS-DA) were utilized for finding characteristic metabolite changes induced by two PPP procedures; centrifugation and filtration. We used 12-h fasting samples and postprandial samples collected at 2h after a standardized high-fat protein-rich meal in obese non-diabetic subjects recruited in a dietary intervention. The two PPP procedures as well as external and internal standards (ISs) were used to track errors in response normalization and quantification. Remarkably and sometimes uniquely, the fPPP, but not the cPPP approach, recovered not only high molecular weight (HMW) lipophilic metabolites, but also small molecular weight (SMW) relatively polar metabolites. Characteristic SMW markers of postprandial samples were aromatic and branched-chain amino acids that were elevated (p<0.001) as a consequence of the protein challenge. In contrast, some HMW lipophilic species, e.g. acylcarnitines, were moderately lower (p<0.001) in postprandial samples. LysoPCs were largely unaffected. In conclusion, the fPPP procedure is recommended for processing high-fat plasma samples in metabolomics studies. While method improvements presented here were clear, use of several ISs revealed substantial challenges to untargeted metabolomics due to large and variable matrix effects. Copyright © 2012 Elsevier B.V. All rights reserved.

Concordance analysis of methylation biomarkers detection in self-collected and physician-collected samples in cervical neoplasm

International Nuclear Information System (INIS)

Chang, Cheng-Chang; Huang, Rui-Lan; Liao, Yu-Ping; Su, Po-Hsuan; Hsu, Yaw-Wen; Wang, Hui-Chen; Tien, Chau-Yang; Yu, Mu-Hsien; Lin, Ya-Wen; Lai, Hung-Cheng

2015-01-01

Non-attendance at gynecological clinics is a major limitation of cervical cancer screening and self-collection of samples may improve this situation. Although HPV testing of self-collected vaginal samples is acceptable, the specificity is inadequate. The current focus is increasing self-collection of vaginal samples to minimize clinic visits. In this study, we analyzed the concordance and clinical performance of DNA methylation biomarker (PAX1, SOX1, and ZNF582) detection in self-collected vaginal samples and physician-collected cervical samples for the identification of cervical neoplasm. We enrolled 136 cases with paired methylation data identified from abnormal Pap smears (n = 126) and normal controls (n = 10) regardless of HPV status at gynecological clinics. The study group comprised 37 cervical intraepithelial neoplasm I (CIN1), 23 cervical intraepithelial neoplasm II (CIN2), 16 cervical intraepithelial neoplasm III (CIN3), 30 carcinoma in situ (CIS), 13 squamous cell carcinomas (SCCs) and seven adenocarcinomas (ACs)/adenosquamous carcinomas (ASCs). PAX1, SOX1 and ZNF582 methylation in study samples was assessed by real-time quantitative methylation-specific polymerase chain reaction analysis. We generated methylation index cutoff values for the detection of CIN3+ in physician-collected cervical samples for analysis of the self-collected group. Concordance between the physician-collected and self-collected groups was evaluated by Cohen’s Kappa. Sensitivity, specificity and area under curve (AUC) were calculated for detection of CIN3+ lesions. Finally, we produced an optimal cutoff value with the best sensitivity from the self-collected groups. We generated a methylation index cutoff value from physician-collected samples for detection of CIN3+. There were no significant differences in sensitivity, specificity of PAX1, SOX1 and ZNF582 between the self-collected and physician-collected groups. The methylation status of all three genes in the normal control

Human herpesvirus infections of the central nervous system: laboratory diagnosis based on DNA detection by nested PCR in plasma and cerebrospinal fluid samples.

Science.gov (United States)

Rimério, Carla Aparecida Tavares; De Oliveira, Renato Souza; de Almeida Bonatelli, Murilo Queiroz; Nucci, Anamarli; Costa, Sandra Cecília Botelho; Bonon, Sandra Helena Alves

2015-04-01

Infections of the central nervous systems (CNS) present a diagnostic problem for which an accurate laboratory diagnosis is essential. Invasive practices, such as cerebral biopsy, have been replaced by obtaining a polymerase chain reaction (PCR) diagnosis using cerebral spinal fluid (CSF) as a reference method. Tests on DNA extracted from plasma are noninvasive, thus avoiding all of the collateral effects and patient risks associated with CSF collection. This study aimed to determine whether plasma can replace CSF in nested PCR analysis for the detection of CNS human herpesvirus (HHV) diseases by analysing the proportion of patients whose CSF nested PCR results were positive for CNS HHV who also had the same organism identified by plasma nested PCR. In this study, CSF DNA was used as the "gold standard," and nested PCR was performed on both types of samples. Fifty-two patients with symptoms of nervous system infection were submitted to CSF and blood collection. For the eight HHV, one positive DNA result-in plasma and/or CSF nested PCR-was considered an active HHV infection, whereas the occurrence of two or more HHVs in the same sample was considered a coinfection. HHV infections were positively detected in 27/52 (51.9%) of the CSF and in 32/52 (61.5%) of the plasma, difference not significant, thus nested PCR can be performed on plasma instead of CSF. In conclusion, this findings suggest that plasma as a useful material for the diagnosis of cases where there is any difficulty to perform a CSF puncture. © 2015 Wiley Periodicals, Inc.

Evaluation of Sample Stability and Automated DNA Extraction for Fetal Sex Determination Using Cell-Free Fetal DNA in Maternal Plasma

Directory of Open Access Journals (Sweden)

Elena Ordoñez

2013-01-01

Full Text Available Objective. The detection of paternally inherited sequences in maternal plasma, such as the SRY gene for fetal sexing or RHD for fetal blood group genotyping, is becoming part of daily routine in diagnostic laboratories. Due to the low percentage of fetal DNA, it is crucial to ensure sample stability and the efficiency of DNA extraction. We evaluated blood stability at 4°C for at least 24 hours and automated DNA extraction, for fetal sex determination in maternal plasma. Methods. A total of 158 blood samples were collected, using EDTA-K tubes, from women in their 1st trimester of pregnancy. Samples were kept at 4°C for at least 24 hours before processing. An automated DNA extraction was evaluated, and its efficiency was compared with a standard manual procedure. The SRY marker was used to quantify cfDNA by real-time PCR. Results. Although lower cfDNA amounts were obtained by automated DNA extraction (mean 107,35 GE/mL versus 259,43 GE/mL, the SRY sequence was successfully detected in all 108 samples from pregnancies with male fetuses. Conclusion. We successfully evaluated the suitability of standard blood tubes for the collection of maternal blood and assessed samples to be suitable for analysis at least 24 hours later. This would allow shipping to a central reference laboratory almost from anywhere in Europe.

Accuracy and Precision in Elemental Analysis of Environmental Samples using Inductively Coupled Plasma-Atomic Emission Spectrometry

International Nuclear Information System (INIS)

Quraishi, Shamsad Begum; Chung, Yong-Sam; Choi, Kwang Soon

2005-01-01

Inductively Coupled Plasma-Atomic Emission Spectrometry followed by micro-wave digestion have been performed on different environmental Certified Reference Materials (CRMs). Analytical results show that accuracy and precision in ICP-AES analysis were acceptable and satisfactory in case of soil and hair CRM samples. The relative error of most of the elements in these two CRMs is within 10% with few exceptions and coefficient of variation is also less than 10%. Z-score as an analytical performance was also within the acceptable range (±2). ICP-AES was found as an inadequate method for Air Filter CRM due to incomplete dissolution, low concentration of elements and very low mass of the sample. However, real air filter sample could have been analyzed with high accuracy and precision by increasing sample mass during collection. (author)

Effects of multiple collections on spermatozoa quality of Persian sturgeon, Acipenser persicus: motility, density and seminal plasma composition.

Science.gov (United States)

Aramli, M S; Kalbassi, M R; Gharibi, M R

2015-02-01

In this study, we investigated the effects of multiple collections of sperm on the endangered Persian sturgeon, Acipenser persicus, in terms of a number of sperm functional parameters (percentage of motile spermatozoa, total time period of motility and sperm concentration) as well as on the ionic composition, protein concentration and osmolality of seminal plasma. Semen samples were collected from 12 induced male fish in three experimental groups that had been injected intramuscularly with LHRH-A2, at dosages of 5 μg/kg body weight, at a number of time regimes: at 12 h, 17 h and 24 h after spawning induction (1); at 24, 29 and 34 h after spawning induction (2); and at 36, 41 and 46 h after spawning induction (3). The percentage of motile spermatozoa and the period of sperm motility decreased significantly (p collections. The concentration of spermatozoa decreased after the third collection, but this decline was not significant. No significant effect of multiple collections on protein concentration and ionic content (with exception of the Cl(-) ion) of seminal plasma was observed. In all experimental groups, a moderate impact of sequential collection on the osmolality (p collections on spermatological characteristics in the Persian sturgeon. Our results confirm that sequential stripping after the third collections has a negative effect on a number of functional parameters associated with sperm. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Measurements of plasma composition in the TEXTOR tokamak by collective Thomson scattering

DEFF Research Database (Denmark)

Stejner Pedersen, Morten; Korsholm, Søren Bang; Nielsen, Stefan Kragh

2012-01-01

We demonstrate the use of collective Thomson scattering (CTS) for spatially localized measurements of the isotopic composition of magnetically confined fusion plasmas. The experiments were conducted in the TEXTOR tokamak by scattering millimeter-wave probe radiation off plasma fluctuations...... with wave vector components nearly perpendicular to the magnetic field. Under such conditions the sensitivity of the CTS spectrum to plasma composition is enhanced by the spectral signatures of the ion cyclotron motion and of weakly damped ion Bernstein waves. Recent experiments on TEXTOR demonstrated...... the ability to resolve these signatures in the CTS spectrum as well as their sensitivity to the ion species mix in the plasma. This paper shows that the plasma composition can be inferred from the measurements through forward modeling of the CTS spectrum. We demonstrate that spectra measured in plasmas...

Mass spectrometric identification of diagnostic markers for chronic prostatitis in seminal plasma by analysis of seminal plasma protein clinical samples.

Science.gov (United States)

Rokka, A; Mehik, A; Tonttila, P; Vaarala, M

2017-08-15

There are few specific diagnostic markers for chronic prostatitis. Therefore, we used mass spectrometry to evaluate differences in seminal plasma protein expression among patients with prostatitis and young and middle-aged healthy controls. We analysed pooled seminal plasma protein samples from four prostatitis patients (two pools), three young controls (one pool), and three middle-aged controls (one pool). The samples were analysed by liquid chromatography-tandem mass spectrometry. Of the 349 proteins identified, 16 were differentially expressed between the two control pools. Five proteins were up- or down-regulated in both of the prostatitis pools compared to middle-aged controls but not between young and middle-aged pools. Progestagen-associated endometrial protein (PAEP) was over-expressed in prostatitis samples compared to young and middle-aged controls. Our findings and those of previous studies indicate that PAEP is a potential seminal plasma marker for chronic prostatitis. In conclusion, we found age-related changes in seminal plasma protein expression. PAEP expression in seminal plasma should be investigated further to evaluate its potential as a diagnostic marker for chronic prostatitis.

Proteomic Biomarker Discovery in 1000 Human Plasma Samples with Mass Spectrometry.

Science.gov (United States)

Cominetti, Ornella; Núñez Galindo, Antonio; Corthésy, John; Oller Moreno, Sergio; Irincheeva, Irina; Valsesia, Armand; Astrup, Arne; Saris, Wim H M; Hager, Jörg; Kussmann, Martin; Dayon, Loïc

2016-02-05

The overall impact of proteomics on clinical research and its translation has lagged behind expectations. One recognized caveat is the limited size (subject numbers) of (pre)clinical studies performed at the discovery stage, the findings of which fail to be replicated in larger verification/validation trials. Compromised study designs and insufficient statistical power are consequences of the to-date still limited capacity of mass spectrometry (MS)-based workflows to handle large numbers of samples in a realistic time frame, while delivering comprehensive proteome coverages. We developed a highly automated proteomic biomarker discovery workflow. Herein, we have applied this approach to analyze 1000 plasma samples from the multicentered human dietary intervention study "DiOGenes". Study design, sample randomization, tracking, and logistics were the foundations of our large-scale study. We checked the quality of the MS data and provided descriptive statistics. The data set was interrogated for proteins with most stable expression levels in that set of plasma samples. We evaluated standard clinical variables that typically impact forthcoming results and assessed body mass index-associated and gender-specific proteins at two time points. We demonstrate that analyzing a large number of human plasma samples for biomarker discovery with MS using isobaric tagging is feasible, providing robust and consistent biological results.

Levitation and dynamics of a collection of dust particles in a fully ionized plasma sheath

International Nuclear Information System (INIS)

Nitter, T.; Aslaksen, T.K.; Melandsoe, F.; Havnes, O.

1994-01-01

The authors have examined the dynamics of a collection of charged dust particles in the plasma sheath above a large body in a fully ionized space plasma when the radius of the large body is much larger than the sheath thickness. The dust particles are charged by the plasma, and the forces on the dust particles are assumed to be from the electric field in the sheath and from gravitation only. These forces will often act in opposite direction and may balance, making dust suspension and collection possible. The dust particles are supplied by injection or by electrostatic levitation. The ability of the sheath to collect dust particles, will be optimal for a certain combination of gravitation and plasma and dust particle parameters. In a dense dust sheath, the charges on the dust particles contribute significantly to the total space charge, and collective effects become important. These effects will reduce the magnitude of the sheath electric field strength and the charge on the dust particles. As dust particles are collected, the dust sheath is stretched and the largest dust particles may drop out, because the sheath is no longer able to suspend them. In a tenuous dust sheath, the inner layer, from the surface and about one Debye length thick, will be unstable for dust particle motion, and dust will not collect there. In a dense dust sheath, collective effects will decrease the thickness of this inner dust-free layer, making dust collection closer to the surface possible. By linearization of the force and current equations, they find the necessary and sufficient conditions which resemble those of planetary system bodies, but the results may also be of relevance to some laboratory plasmas

Collective attraction of equal-sign charged grains in plasmas

International Nuclear Information System (INIS)

Tsytovich, V.N.; Morfill, G.E.

2002-01-01

It is shown that, in the presence of many grains embedded in a plasma, any two grains with the same charge sign can attract each other. The attraction is caused by collective effects. Both the strength of attraction and the distance at which the attraction is located depend on the average dust density. In the limit of strong collective interaction, the potential energy of interaction is found to be equal to the Coulomb interaction with an amplitude periodically changing its sign at a sequence of interdust distances. The condition for collective effects to dominate lead to a threshold condition that is fulfilled in existing experiments. The effect of collective attraction is applied for the physical interpretation of the observed phenomenon of the formation of dust crystals in laboratory experiments

Three-phase double-arc plasma for spectrochemical analysis of environmental samples.

Science.gov (United States)

Mohamed, M M; Ghatass, Z F; Shalaby, E A; Kotb, M M; El-Raey, M

2000-12-01

A new instrument, which uses a three-phase current to support a double-arc argon plasma torch for evaporation, atomization and excitation of solid or powder samples, is described. The sampling arc is ignited between the first and second electrode while the excitation arc is ignited between the second and third electrode. Aerosol generated from the sample (first electrode) is swept by argon gas, through a hole in the second electrode (carbon tubing electrode), into the excitation plasma. A tangential stream of argon gas is introduced through an inlet orifice as a coolant gas for the second electrode. This gas stream forces the excitation arc discharge to rotate reproducibly around the electrode surface. Discharge rotation increases the stability of the excitation plasma. Spectroscopic measurements are made directly in the current-carrying region of the excitation arc. An evaluation of each parameter influencing the device performance was performed. Analytical calibration curves were obtained for Fe, Al, K, and Pb. Finally, the present technique was applied for the analysis of environmental samples. The present method appears to have significant, low cost analytical utility for environmental measurements.

Direct trace-elemental analysis of urine samples by laser ablation-inductively coupled plasma mass spectrometry after sample deposition on clinical filter papers.

Science.gov (United States)

Aramendía, Maite; Rello, Luis; Vanhaecke, Frank; Resano, Martín

2012-10-16

Collection of biological fluids on clinical filter papers shows important advantages from a logistic point of view, although analysis of these specimens is far from straightforward. Concerning urine analysis, and particularly when direct trace elemental analysis by laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) is aimed at, several problems arise, such as lack of sensitivity or different distribution of the analytes on the filter paper, rendering obtaining reliable quantitative results quite difficult. In this paper, a novel approach for urine collection is proposed, which circumvents many of these problems. This methodology consists on the use of precut filter paper discs where large amounts of sample can be retained upon a single deposition. This provides higher amounts of the target analytes and, thus, sufficient sensitivity, and allows addition of an adequate internal standard at the clinical lab prior to analysis, therefore making it suitable for a strategy based on unsupervised sample collection and ulterior analysis at referral centers. On the basis of this sampling methodology, an analytical method was developed for the direct determination of several elements in urine (Be, Bi, Cd, Co, Cu, Ni, Sb, Sn, Tl, Pb, and V) at the low μg L(-1) level by means of LA-ICPMS. The method developed provides good results in terms of accuracy and LODs (≤1 μg L(-1) for most of the analytes tested), with a precision in the range of 15%, fit-for-purpose for clinical control analysis.

Relative Abundance of Proteins in Blood Plasma Samples from Patients with Chronic Cerebral Ischemia.

Science.gov (United States)

Kaysheva, Anna L; Kopylov, Artur T; Ponomarenko, Elena A; Kiseleva, Olga I; Teryaeva, Nadezhda B; Potapov, Alexander A; Izotov, Alexander А; Morozov, Sergei G; Kudryavtseva, Valeria Yu; Archakov, Alexander I

2018-03-01

A comparative protein profile analysis of 17 blood plasma samples from patients with ischemia and 20 samples from healthy volunteers was carried out using ultra-high resolution mass spectrometry. The analysis of measurements was performed using the proteomics search engine OMSSA. Normalized spectrum abundance factor (NSAF) in the biological samples was assessed using SearchGUI. The findings of mass spectrometry analysis of the protein composition of blood plasma samples demonstrate that the depleted samples are quite similar in protein composition and relative abundance of proteins. By comparing them with the control samples, we have found a small group of 44 proteins characteristic of the blood plasma samples from patients with chronic cerebral ischemia. These proteins contribute to the processes of homeostasis maintenance, including innate immune response unfolding, the response of a body to stress, and contribution to the blood clotting cascade.

Ion collection from laser-induced plasma by applying radio-frequency voltage

International Nuclear Information System (INIS)

Shibata, Takemasa; Ogura, Koichi

1995-01-01

Ions were collected on the electrodes from a laser resonance photoionized plasma by applying 1.8MHz radio-frequency voltage to the electrode. It was demonstrated that the ions are collected in a shorter time at the same kinetic energy of the collected ions compared with ion collection by applying DC voltage to the electrode. A simple one-dimensional model was extended for prediction of ion collection times in the cases of applications of not only the DC voltage but also the radio-frequency voltage. The ion collection times estimated using the simple one-dimensional model agreed with experimental values in both cases of DC and radio-frequency voltages. (author)

Sample collections from healthy volunteers for biological variation estimates' update: a new project undertaken by the Working Group on Biological Variation established by the European Federation of Clinical Chemistry and Laboratory Medicine.

Science.gov (United States)

Carobene, Anna; Strollo, Marta; Jonker, Niels; Barla, Gerhard; Bartlett, William A; Sandberg, Sverre; Sylte, Marit Sverresdotter; Røraas, Thomas; Sølvik, Una Ørvim; Fernandez-Calle, Pilar; Díaz-Garzón, Jorge; Tosato, Francesca; Plebani, Mario; Coşkun, Abdurrahman; Serteser, Mustafa; Unsal, Ibrahim; Ceriotti, Ferruccio

2016-10-01

Biological variation (BV) data have many fundamental applications in laboratory medicine. At the 1st Strategic Conference of the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) the reliability and limitations of current BV data were discussed. The EFLM Working Group on Biological Variation is working to increase the quality of BV data by developing a European project to establish a biobank of samples from healthy subjects to be used to produce high quality BV data. The project involved six European laboratories (Milan, Italy; Bergen, Norway; Madrid, Spain; Padua, Italy; Istanbul, Turkey; Assen, The Netherlands). Blood samples were collected from 97 volunteers (44 men, aged 20-60 years; 43 women, aged 20-50 years; 10 women, aged 55-69 years). Initial subject inclusion required that participants completed an enrolment questionnaire to verify their health status. The volunteers provided blood specimens once per week for 10 weeks. A short questionnaire was completed and some laboratory tests were performed at each sampling consisting of blood collected under controlled conditions to provide serum, K2EDTA-plasma and citrated-plasma samples. Samples from six out of the 97 enroled subjects were discarded as a consequence of abnormal laboratory measurements. A biobank of 18,000 aliquots was established consisting of 120 aliquots of serum, 40 of EDTA-plasma, and 40 of citrated-plasma from each subject. The samples were stored at -80 °C. A biobank of well-characterised samples collected under controlled conditions has been established delivering a European resource to enable production of contemporary BV data.

Radionuclide determination in environmental samples by inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Lariviere, Dominic; Taylor, Vivien F.; Evans, R. Douglas; Cornett, R. Jack

2006-01-01

The determination of naturally occurring and anthropogenic radionuclides in the environment by inductively coupled plasma mass spectrometry has gained recognition over the last fifteen years, relative to radiometric techniques, as the result of improvement in instrumental performance, sample introduction equipment, and sample preparation. With the increase in instrumental sensitivity, it is now possible to measure ultratrace levels (fg range) of many radioisotopes, including those with half-lives between 1 and 1000 years, without requiring very complex sample pre-concentration schemes. However, the identification and quantification of radioisotopes in environmental matrices is still hampered by a variety of analytical issues such as spectral (both atomic and molecular ions) and non-spectral (matrix effect) interferences and instrumental limitations (e.g., abundance sensitivity). The scope of this review is to highlight recent analytical progress and issues associated with the determination of radionuclides by inductively coupled plasma mass spectrometry. The impact of interferences, instrumental limitations (e.g., degree of ionization, abundance sensitivity, detection limits) and low sample-to-plasma transfer efficiency on the measurement of radionuclides by inductively coupled plasma mass spectrometry will be described. Solutions that overcome these issues will be discussed, highlighting their pros and cons and assessing their impact on the measurement of environmental radioactivity. Among the solutions proposed, mass and chemical resolution through the use of sector-field instruments and chemical reactions/collisions in a pressurized cell, respectively, will be described. Other methods, such as unique sample introduction equipment (e.g., laser ablation, electrothermal vaporisation, high efficiency nebulization) and instrumental modifications/optimizations (e.g., instrumental vacuum, radiofrequency power, guard electrode) that improve sensitivity and performance

Water sample-collection and distribution system

Science.gov (United States)

Brooks, R. R.

1978-01-01

Collection and distribution system samples water from six designated stations, filtered if desired, and delivers it to various analytical sensors. System may be controlled by Water Monitoring Data Acquisition System or operated manually.

Characterization Of Core Sample Collected From The Saltstone Disposal Facility

International Nuclear Information System (INIS)

Cozzi, A.; Duncan, A.

2010-01-01

During the month of September 2008, grout core samples were collected from the Saltstone Disposal Facility, Vault 4, cell E. This grout was placed during processing campaigns in December 2007 from Deliquification, Dissolution and Adjustment Batch 2 salt solution. The 4QCY07 Waste Acceptance Criteria sample collected on 11/16/07 represents the salt solution in the core samples. Core samples were retrieved to initiate the historical database of properties of emplaced Saltstone and to demonstrate the correlation between field collected and laboratory prepared samples. Three samples were collected from three different locations. Samples were collected using a two-inch diameter concrete coring bit. In April 2009, the core samples were removed from the evacuated sample container, inspected, transferred to PVC containers, and backfilled with nitrogen. Samples furthest from the wall were the most intact cylindrically shaped cored samples. The shade of the core samples darkened as the depth of coring increased. Based on the visual inspection, sample 3-3 was selected for all subsequent analysis. The density and porosity of the Vault 4 core sample, 1.90 g/cm 3 and 59.90% respectively, were comparable to values achieved for laboratory prepared samples. X-ray diffraction analysis identified phases consistent with the expectations for hydrated Saltstone. Microscopic analysis revealed morphology features characteristic of cementitious materials with fly ash and calcium silicate hydrate gel. When taken together, the results of the density, porosity, x-ray diffraction analysis and microscopic analysis support the conclusion that the Vault 4, Cell E core sample is representative of the expected waste form.

Assessing human error during collecting a hydrocarbon sample of ...

African Journals Online (AJOL)

This paper reports the assessment method of the hydrocarbon sample collection standard operation procedure (SOP) using THERP. The Performance Shaping Factors (PSF) from THERP analyzed and assessed the human errors during collecting a hydrocarbon sample of a petrochemical refinery plant. Twenty-two ...

Turbulence in Wendelstein 7-AS plasmas measured by collective light scattering

Energy Technology Data Exchange (ETDEWEB)

Basse, Nils Plesner

2002-08-01

This Ph.D. thesis contains theoretical and experimental work on plasma turbulence measurements using collective light scattering. The motivation for measuring turbulence in hot fusion plasmas is, along with the method used and results obtained, the subject of chapter 1. The theoretical part is divided into three chapters. Chapter 2 contains a full analytical derivation of the expected dependency of the detected signal on plasma parameters. Thereafter, spatial resolution of the measurements using different methods is treated in chapter 3. Finally, the spectral analysis tools used later in the thesis are described and illustrated in chapter 4. The experimental part is divided into four chapters. In chapter 5 transport concepts relevant to the thesis are outlined. Main parameters of the Wendelstein 7-AS (W7-AS) stellarator in which measurements were made are collected in chapter 6. The setup used to study fluctuations in the electron density of W7-AS plasmas is covered in chapter 7. This localised turbulence scattering (LOTUS) diagnostic is based on a CO{sub 2} laser radiating at a wavelength of 10.59 {mu}m. Fast, heterodyne, dual volume detection at variable wavenumbers between 14 and 62 cm{sup -1} is performed. The central chapter of the thesis, chapter 8, contains an analysis of the measured density fluctuations before, during and after several confinement transition types. The aim was to achieve a better understanding of the connection between turbulence and the confinement quality of the plasma. Conclusions and suggestions for further work are summarised in chapter 9. (au)

Turbulence in Wendelstein 7-AS plasmas measured by collective light scattering

International Nuclear Information System (INIS)

Basse, Nils Plesner

2002-08-01

This Ph.D. thesis contains theoretical and experimental work on plasma turbulence measurements using collective light scattering. The motivation for measuring turbulence in hot fusion plasmas is, along with the method used and results obtained, the subject of chapter 1. The theoretical part is divided into three chapters. Chapter 2 contains a full analytical derivation of the expected dependency of the detected signal on plasma parameters. Thereafter, spatial resolution of the measurements using different methods is treated in chapter 3. Finally, the spectral analysis tools used later in the thesis are described and illustrated in chapter 4. The experimental part is divided into four chapters. In chapter 5 transport concepts relevant to the thesis are outlined. Main parameters of the Wendelstein 7-AS (W7-AS) stellarator in which measurements were made are collected in chapter 6. The setup used to study fluctuations in the electron density of W7-AS plasmas is covered in chapter 7. This localised turbulence scattering (LOTUS) diagnostic is based on a CO 2 laser radiating at a wavelength of 10.59 μm. Fast, heterodyne, dual volume detection at variable wavenumbers between 14 and 62 cm -1 is performed. The central chapter of the thesis, chapter 8, contains an analysis of the measured density fluctuations before, during and after several confinement transition types. The aim was to achieve a better understanding of the connection between turbulence and the confinement quality of the plasma. Conclusions and suggestions for further work are summarised in chapter 9. (au)

Scientific guidelines for preservation of samples collected from Mars

International Nuclear Information System (INIS)

Gooding, J.L.

1990-04-01

The maximum scientific value of Martian geologic and atmospheric samples is retained when the samples are preserved in the conditions that applied prior to their collection. Any sample degradation equates to loss of information. Based on detailed review of pertinent scientific literature, and advice from experts in planetary sample analysis, number values are recommended for key parameters in the environmental control of collected samples with respect to material contamination, temperature, head-space gas pressure, ionizing radiation, magnetic fields, and acceleration/shock. Parametric values recommended for the most sensitive geologic samples should also be adequate to preserve any biogenic compounds or exobiological relics

Experimental and Sampling Design for the INL-2 Sample Collection Operational Test

Energy Technology Data Exchange (ETDEWEB)

Piepel, Gregory F.; Amidan, Brett G.; Matzke, Brett D.

2009-02-16

This report describes the experimental and sampling design developed to assess sampling approaches and methods for detecting contamination in a building and clearing the building for use after decontamination. An Idaho National Laboratory (INL) building will be contaminated with BG (Bacillus globigii, renamed Bacillus atrophaeus), a simulant for Bacillus anthracis (BA). The contamination, sampling, decontamination, and re-sampling will occur per the experimental and sampling design. This INL-2 Sample Collection Operational Test is being planned by the Validated Sampling Plan Working Group (VSPWG). The primary objectives are: 1) Evaluate judgmental and probabilistic sampling for characterization as well as probabilistic and combined (judgment and probabilistic) sampling approaches for clearance, 2) Conduct these evaluations for gradient contamination (from low or moderate down to absent or undetectable) for different initial concentrations of the contaminant, 3) Explore judgment composite sampling approaches to reduce sample numbers, 4) Collect baseline data to serve as an indication of the actual levels of contamination in the tests. A combined judgmental and random (CJR) approach uses Bayesian methodology to combine judgmental and probabilistic samples to make clearance statements of the form "X% confidence that at least Y% of an area does not contain detectable contamination” (X%/Y% clearance statements). The INL-2 experimental design has five test events, which 1) vary the floor of the INL building on which the contaminant will be released, 2) provide for varying the amount of contaminant released to obtain desired concentration gradients, and 3) investigate overt as well as covert release of contaminants. Desirable contaminant gradients would have moderate to low concentrations of contaminant in rooms near the release point, with concentrations down to zero in other rooms. Such gradients would provide a range of contamination levels to challenge the sampling

PIXE elemental analysis of erythrocyte and blood plasma samples from human pregnancies

International Nuclear Information System (INIS)

Borbely-Kiss, I.; Koltay, E.; Laszlo, S.; Szabo, Gy.

1984-01-01

Elemental concentrations of P, S, Cl, K, Ca, Fe, Ni, Cu, Zn, Br, Rb have been determined in erythrocyte and blood plasma samples from normal and diabetic human pregnancies. Average values, the dependence of the concentrations on the time during gestation period, the correlation coefficients for pairs of elements as well as for the same elements in plasma and erythrocyte samples are given. A marked difference appeared in a number of cases between normal and diabetic pregnancies. (author)

PIXE elemental analysis of erythrocyte and blood plasma samples from human pregnancies

Energy Technology Data Exchange (ETDEWEB)

Borbely-Kiss, I; Koltay, E; Laszlo, S; Szabo, Gy [Magyar Tudomanyos Akademia, Debrecen. Atommag Kutato Intezete; Goedeny, S [Orvostudomanyi Egyetem, Szeged (Hungary). Szueleszeti es Noegyogyaszati Klinika; Seif El-Nasr, S [Teachers' Coll. for Women, Samia (Kuwait)

1984-07-01

Elemental concentrations of P, S, Cl, K, Ca, Fe, Ni, Cu, Zn, Br, Rb have been determined in erythrocyte and blood plasma samples from normal and diabetic human pregnancies. Average values, the dependence of the concentrations on the time during gestation period, the correlation coefficients for pairs of elements as well as for the same elements in plasma and erythrocyte samples are given. A marked difference appeared in a number of cases between normal and diabetic pregnancies. 11 refs.

78 FR 46954 - Agency Information Collection Activities; Proposed Collection; Comment Request; Draft Guidance...

Science.gov (United States)

2013-08-02

... either electronic or written comments on the collection of information by October 1, 2013. ADDRESSES: Submit electronic comments on the collection of information to http://www.regulations.gov . Submit... detecting antibodies to T. cruzi in plasma and serum samples from individual human donors, including donors...

Method validation in plasma source optical emission spectroscopy (ICP-OES) - From samples to results

International Nuclear Information System (INIS)

Pilon, Fabien; Vielle, Karine; Birolleau, Jean-Claude; Vigneau, Olivier; Labet, Alexandre; Arnal, Nadege; Adam, Christelle; Camilleri, Virginie; Amiel, Jeanine; Granier, Guy; Faure, Joel; Arnaud, Regine; Beres, Andre; Blanchard, Jean-Marc; Boyer-Deslys, Valerie; Broudic, Veronique; Marques, Caroline; Augeray, Celine; Bellefleur, Alexandre; Bienvenu, Philippe; Delteil, Nicole; Boulet, Beatrice; Bourgarit, David; Brennetot, Rene; Fichet, Pascal; Celier, Magali; Chevillotte, Rene; Klelifa, Aline; Fuchs, Gilbert; Le Coq, Gilles; Mermet, Jean-Michel

2017-01-01

Even though ICP-OES (Inductively Coupled Plasma - Optical Emission Spectroscopy) is now a routine analysis technique, requirements for measuring processes impose a complete control and mastering of the operating process and of the associated quality management system. The aim of this (collective) book is to guide the analyst during all the measurement validation procedure and to help him to guarantee the mastering of its different steps: administrative and physical management of samples in the laboratory, preparation and treatment of the samples before measuring, qualification and monitoring of the apparatus, instrument setting and calibration strategy, exploitation of results in terms of accuracy, reliability, data covariance (with the practical determination of the accuracy profile). The most recent terminology is used in the book, and numerous examples and illustrations are given in order to a better understanding and to help the elaboration of method validation documents

An evaluation of multiplex bead-based analysis of cytokines and soluble proteins in archived lithium heparin plasma, EDTA plasma and serum samples

DEFF Research Database (Denmark)

Brøndum, Line; Sørensen, Brita Singers; Eriksen, Jesper Grau

2016-01-01

-13, and VEGF, LH plasma levels vs. EDTA plasma: IL-2 and IL-4. CONCLUSION: Stored serum, LH plasma, and EDTA plasma from clinical trials can be used for analysis of circulating cytokines and proteins. Variations in measurements occur, but are within reasonable ranges. The optimal type of media...... in plasma and serum from 86 head and neck cancer patients and 33 controls were evaluated: EGFR, leptin, OPN, VEGFR-1, VEGFR-2, IL-2, IL-13, PDGF-bb, TNF, PAI-1, SDF-1a, IL-4, IL-6, IL-8, eotaxin, G-CSF, VEGF, GRO-a, and HGF. RESULTS: The correlation between measurements of the same samples analyzed...... on different dates was reasonable. However, samples run on different dates could exhibit different absolute values. The 75th percentile of the fold differences for samples run on different dates was 2.2. No significant difference was found between one and four freeze-thaw cycles (except for HGF...

Composition of Trace Metals in Dust Samples Collected from Selected High Schools in Pretoria, South Africa

Directory of Open Access Journals (Sweden)

J. O. Olowoyo

2016-01-01

Full Text Available Potential health risks associated with trace metal pollution have necessitated the importance of monitoring their levels in the environment. The present study investigated the concentrations and compositions of trace metals in dust samples collected from classrooms and playing ground from the selected high schools In Pretoria. Schools were selected from Pretoria based on factors such as proximity to high traffic ways, industrial areas, and residential areas. Thirty-two dust samples were collected from inside and outside the classrooms, where learners often stay during recess period. The dust samples were analysed for trace metal concentrations using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS. The composition of the elements showed that the concentrations of Zn were more than all other elements except from one of the schools. There were significant differences in the concentrations of trace metals from the schools (p<0.05. Regular cleaning, proximity to busy road, and well maintained gardens seem to have positive effects on the concentrations of trace metals recorded from the classrooms dust. The result further revealed a positive correlation for elements such as Pb, Cu, Zn, Mn, and Sb, indicating that the dust might have a common source.

Inductively coupled plasma mass spectrometry in the analysis of biological samples and pharmaceutical drugs

Science.gov (United States)

Ossipov, K.; Seregina, I. F.; Bolshov, M. A.

2016-04-01

Inductively coupled plasma mass spectrometry (ICP-MS) is widely used in the analysis of biological samples (whole blood, serum, blood plasma, urine, tissues, etc.) and pharmaceutical drugs. The shortcomings of this method related to spectral and non-spectral interferences are manifested in full measure in determination of the target analytes in these complex samples strongly differing in composition. The spectral interferences are caused by similarity of masses of the target component and sample matrix components. Non-spectral interferences are related to the influence of sample matrix components on the physicochemical processes taking place during formation and transportation of liquid sample aerosols into the plasma, on the value and spatial distribution of plasma temperature and on the transmission of the ion beam from the interface to mass spectrometer detector. The review is devoted to analysis of different mechanisms of appearance of non-spectral interferences and to ways for their minimization or elimination. Special attention is paid to the techniques of biological sample preparation, which largely determine the mechanisms of the influence of sample composition on the results of element determination. The ways of lowering non-spectral interferences by instrumental parameter tuning and application of internal standards are considered. The bibliography includes 189 references.

Collection and preparation of samples for gamma spectrometry

International Nuclear Information System (INIS)

Pan Jingquan

1994-01-01

The paper presents the basic principles of sample collection and preparation: setting up unified sampling program, methods and procedures, sample packing, transportation and storage, determination of sample quantity, sample pretreatment and preparation of samples to be analysed, etc. for gamma spectrometry. And the paper also describes briefly the main methods and special issues of sampling and preparation for the same environmental and biological samples, such as, air, water, grass, soil and foods

Fieldwork and catalogue of samples collected in Polan, September 1995

Energy Technology Data Exchange (ETDEWEB)

Poulsen, N.; Drewniak, A.; Glowniak, E.; Ineson, J.; Matyja, B.A.; Merta, T.; Wierzbowski, A.

1995-12-31

This report lists the collection of samples taken during the field work of the EFP-95 Project, named `The Polish Middle to Late Jurassic Epicratonic basin, stratigraphy, facies and basin history` (short title: Jurrasic basin study, Poland) in Poland, August 7-20, 1995. The samples were collected for palynological studies, and/or sedimentaological studies, and/or source rock studies, and/or reservoir rock characteristics. Prepared samples (slides etc.) are stored in the collections of the GEUS, and remaining rock-material at the store of the GEUS. Field work with collection of samples for palynological studies has been carried earlier in 1988 and at the Oxfordian and Kimmeridgian Joint Working Groups Meeting 1992. (au)

Proteomic biomarker discovery in 1000 human plasma samples with mass spectrometry

DEFF Research Database (Denmark)

Cominetti, Ornella; Núñez Galindo, Antonio; Corthésy, John

2016-01-01

automated proteomic biomarker discovery workflow. Herein, we have applied this approach to analyze 1000 plasma samples from the multicentered human dietary intervention study "DiOGenes". Study design, sample randomization, tracking, and logistics were the foundations of our large-scale study. We checked...

Local regulation of interchange turbulence in a dipole-confined plasma torus using current-collection feedback

International Nuclear Information System (INIS)

Roberts, T. M.; Mauel, M. E.; Worstell, M. W.

2015-01-01

Turbulence in plasma confined by a magnetic dipole is dominated by interchange fluctuations with complex dynamics and short spatial coherence. We report the first use of local current-collection feedback to modify, amplify, and suppress these fluctuations. The spatial extent of turbulence regulation is limited to a correlation length near the collector. Changing the gain and phase of collection results in power either extracted from or injected into the turbulence. The measured plasma response shows some agreement with calculations of the linear response of global interchange-like MHD and entropy modes to current-collection feedback

Self-Collected versus Clinician-Collected Sampling for Chlamydia and Gonorrhea Screening: A Systemic Review and Meta-Analysis

Science.gov (United States)

Lunny, Carole; Taylor, Darlene; Hoang, Linda; Wong, Tom; Gilbert, Mark; Lester, Richard; Krajden, Mel; Ogilvie, Gina

2015-01-01

Background The increases in STI rates since the late 1990s in Canada have occurred despite widespread primary care and targeted public health programs and in the setting of universal health care. More innovative interventions are required that would eliminate barriers to STI testing such as internet-based or mail-in home and community service testing for patients that are hard to reach, who refuse to go for clinician-based testing, or who decline an examination. Jurisdictions such as New Zealand and some American states currently use self-collected sampling, but without the required evidence to determine whether self-collected specimens are as accurate as clinician-collected specimens in terms of chlamydia and gonorrhea diagnostic accuracy. The objective of the review is to compare self-collected vaginal, urine, pharyngeal and rectal samples to our reference standard - clinician-collected cervical, urethral, pharyngeal and rectal sampling techniques to identify a positive specimen using nucleic acid amplification test assays. Methods The hierarchical summary receiver operating characteristic and the fixed effect models were used to assess the accuracy of comparable specimens that were collected by patients compared to clinicians. Sensitivity and specificity estimates with 95% confidence intervals (CI) were reported as our main outcome measures. Findings We included 21 studies based on over 6100 paired samples. Fourteen included studies examined chlamydia only, 6 compared both gonorrhea and chlamydia separately in the same study, and one examined gonorrhea. The six chlamydia studies comparing self-collection by vaginal swab to a clinician-collected cervical swab had the highest sensitivity (92%, 95% CI 87-95) and specificity (98%, 95% CI 97-99), compared to other specimen-types (urine/urethra or urine/cervix). Six studies compared urine self-samples to urethra clinician-collected samples in males and produced a sensitivity of 88% (95% CI 83-93) and a specificity of

Acceptability of self-collected versus provider-collected sampling for HPV DNA testing among women in rural El Salvador.

Science.gov (United States)

Rosenbaum, Alan J; Gage, Julia C; Alfaro, Karla M; Ditzian, Lauren R; Maza, Mauricio; Scarinci, Isabel C; Felix, Juan C; Castle, Philip E; Villalta, Sofia; Miranda, Esmeralda; Cremer, Miriam L

2014-08-01

To determine the acceptability of self-collected versus provider-collected sampling among women participating in public sector HPV-based cervical cancer screening in El Salvador. Two thousand women aged 30-49 years underwent self-collected and provider-collected sampling with careHPV between October 2012 and March 2013 (Qiagen, Gaithersburg, MD, USA). After sample collection, a random sample of women (n=518) were asked about their experience. Participants were questioned regarding sampling method preference, previous cervical cancer screening, HPV and cervical cancer knowledge, HPV risk factors, and demographic information. All 518 women approached to participate in this questionnaire study agreed and were enrolled, 27.8% (142 of 511 responding) of whom had not received cervical cancer screening within the past 3 years and were considered under-screened. Overall, 38.8% (n=201) preferred self-collection and 31.9% (n=165) preferred provider collection. Self-collection preference was associated with prior tubal ligation, HPV knowledge, future self-sampling preference, and future home-screening preference (P<0.05). Reasons for self-collection preference included privacy/embarrassment, ease, and less pain; reasons cited for provider-collection preference were result accuracy and provider knowledge/experience. Self-sampling was found to be acceptable, therefore screening programs could consider offering this option either in the clinic or at home. Self-sampling at home may increase coverage in low-resource countries and reduce the burden that screening places upon clinical infrastructure. Copyright © 2014 International Federation of Gynecology and Obstetrics. All rights reserved.

Dispersive properties and attraction instability of low-frequency collective modes in dusty plasmas

International Nuclear Information System (INIS)

Tsytovich, V.N.; Rezendes, D.

1998-01-01

A dispersion relation for low-frequency collective modes in dusty plasmas is derived with allowance for attractive and repulsive forces arising between the dust grains due to dissipative fluxes of plasma particles onto the grain surfaces. It is shown that these fluxes give rise to dust attraction instabilities, which are similar to the gravitational instability. In the range of wave numbers corresponding to the stability domain, two types of dust sound waves arise, depending on whether the wavelengths of the collective modes are longer or shorter than the mean free path of the plasma particles (i.e., the distance they travel before they collide with dust grains). The dispersion relation derived is valid for any ratio between the wavelength of the perturbations and the mean free path and encompasses the entire range of intermediate wave numbers. The critical wave numbers that determine the threshold for the onset of attraction instability, which is similar to the Jeans instability, can, in particular, lie within this range. The thresholds for attraction instability and the instability growth rates are obtained numerically for a wide range of the plasma parameters (such as the ratio of the ion temperature to the electron temperature) that are of interest for present-day experiments with dust crystals, plasma etching, and space plasma studies. Computer simulation shows that, in the nonlinear stage, the attraction instability causes the dust cloud to collapse, which leads to the formation of dust plasma crystals. Our investigation makes it possible to trace the processes in the initial stage of dust crystallization. Results are obtained for hydrogen and silicon plasmas, which are most typical of laboratory experiments

Simulation of rarefied low pressure RF plasma flow around the sample

Science.gov (United States)

Zheltukhin, V. S.; Shemakhin, A. Yu

2017-01-01

The paper describes a mathematical model of the flow of radio frequency plasma at low pressure. The hybrid mathematical model includes the Boltzmann equation for the neutral component of the RF plasma, the continuity and the thermal equations for the charged component. Initial and boundary conditions for the corresponding equations are described. The electron temperature in the calculations is 1-4 eV, atoms temperature in the plasma clot is (3-4) • 103 K, in the plasma jet is (3.2-10) • 102 K, the degree of ionization is 10-7-10-5, electron density is 1015-1019 m-3. For calculations plasma parameters is developed soft package on C++ program language, that uses the OpenFOAM library package. Simulations for the vacuum chamber in the presence of a sample and the free jet flow were carried out.

Electromagnetic fluctuation spectra of collective oscillations in magnetized Maxwellian plasmas for parallel wave vectors

Science.gov (United States)

Vafin, S.; Schlickeiser, R.; Yoon, P. H.

2016-05-01

The general electromagnetic fluctuation theory for magnetized plasmas is used to calculate the steady-state wave number spectra and total electromagnetic field strength of low-frequency collective weakly damped eigenmodes with parallel wavevectors in a Maxwellian electron-proton plasma. These result from the equilibrium of spontaneous emission and collisionless damping, and they represent the minimum electromagnetic fluctuations guaranteed in quiet thermal space plasmas, including the interstellar and interplanetary medium. Depending on the plasma beta, the ratio of |δB |/B0 can be as high as 10-12 .

Evaluation of standard methods for collecting and processing fuel moisture samples

Science.gov (United States)

Sally M. Haase; José Sánchez; David R. Weise

2016-01-01

A variety of techniques for collecting and processing samples to determine moisture content of wildland fuels in support of fire management activities were evaluated. The effects of using a chainsaw or handsaw to collect samples of largediameter wood, containers for storing and transporting collected samples, and quick-response ovens for estimating moisture content...

A random sampling approach for robust estimation of tissue-to-plasma ratio from extremely sparse data.

Science.gov (United States)

Chu, Hui-May; Ette, Ene I

2005-09-02

his study was performed to develop a new nonparametric approach for the estimation of robust tissue-to-plasma ratio from extremely sparsely sampled paired data (ie, one sample each from plasma and tissue per subject). Tissue-to-plasma ratio was estimated from paired/unpaired experimental data using independent time points approach, area under the curve (AUC) values calculated with the naïve data averaging approach, and AUC values calculated using sampling based approaches (eg, the pseudoprofile-based bootstrap [PpbB] approach and the random sampling approach [our proposed approach]). The random sampling approach involves the use of a 2-phase algorithm. The convergence of the sampling/resampling approaches was investigated, as well as the robustness of the estimates produced by different approaches. To evaluate the latter, new data sets were generated by introducing outlier(s) into the real data set. One to 2 concentration values were inflated by 10% to 40% from their original values to produce the outliers. Tissue-to-plasma ratios computed using the independent time points approach varied between 0 and 50 across time points. The ratio obtained from AUC values acquired using the naive data averaging approach was not associated with any measure of uncertainty or variability. Calculating the ratio without regard to pairing yielded poorer estimates. The random sampling and pseudoprofile-based bootstrap approaches yielded tissue-to-plasma ratios with uncertainty and variability. However, the random sampling approach, because of the 2-phase nature of its algorithm, yielded more robust estimates and required fewer replications. Therefore, a 2-phase random sampling approach is proposed for the robust estimation of tissue-to-plasma ratio from extremely sparsely sampled data.

Simulation of rarefied low pressure RF plasma flow around the sample

International Nuclear Information System (INIS)

Zheltukhin, V S; Shemakhin, A Yu

2017-01-01

The paper describes a mathematical model of the flow of radio frequency plasma at low pressure. The hybrid mathematical model includes the Boltzmann equation for the neutral component of the RF plasma, the continuity and the thermal equations for the charged component. Initial and boundary conditions for the corresponding equations are described. The electron temperature in the calculations is 1-4 eV, atoms temperature in the plasma clot is (3-4) • 10 3 K, in the plasma jet is (3.2-10) • 10 2 K, the degree of ionization is 10 -7 -10 -5 , electron density is 10 15 -10 19 m -3 . For calculations plasma parameters is developed soft package on C++ program language, that uses the OpenFOAM library package. Simulations for the vacuum chamber in the presence of a sample and the free jet flow were carried out. (paper)

Apheresis for collection of Ebola convalescent plasma in Liberia.

Science.gov (United States)

Brown, Jerry F; Rowe, Kathleen; Zacharias, Peter; van Hasselt, James; Dye, John M; Wohl, David A; Fischer, William A; Cunningham, Coleen K; Thielman, Nathan M; Hoover, David L

2017-06-01

This report describes initiation of apheresis capability in Liberia, Africa to support a clinical trial of convalescent plasma therapy for Ebola Virus Disease. A bloodmobile was outfitted in the United States as a four-bed apheresis unit with capabilities including pathogen reduction, electronic blood establishment computer system, designated areas for donor counseling and laboratory testing, and onboard electrical power generation. After air transport to Liberia, the bloodmobile was positioned at ELWA Hospital, Monrovia, and connected to the hospital's power grid. Liberian staff were trained to conduct donor screening, which included questionnaire and onsite blood typing and transfusion transmitted infection (TTI) testing, and plasma collection and processing. The bloodmobile was operational within 3 weeks after arrival of the advance team. Of 101 donors who passed the pre-screening questionnaire, 32 were deferred. Twenty-eight of ninty-nine tested survivors were deferred for positive transfusion transmitted infection (TTI) tests; twenty-one were positive for hepatitis B, hepatitis C, or human immunodeficiency virus. The majority of donors had type O blood; all but one were Rh positive. Forty-three survivors donated at least once; eighty-nine apheresis attempts resulted in eighty-one successful collections. Apheresis capability was emergently established in Liberia to support an efficacy trial of Ebola Convalescent Plasma. Extensive cooperation among multinational team members, engineers, logisticians, and blood safety technical personnel at the operational site was required to surmount challenges to execution posed by logistical factors. The high proportion of positive TTI tests supported the use of a pathogen reduction system to enhance product safety. J. Clin. Apheresis 32:175-181, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Isotopic analysis of calcium in blood plasma and bone from mouse samples by multiple collector-ICP-mass spectrometry

International Nuclear Information System (INIS)

Hirata, Takafumi; Tanoshima, Mina; Suga, Akinobu; Tanaka, Yu-ki; Nagata, Yuichi; Shinohara, Atsuko; Chiba, Momoko

2008-01-01

The biological processing of Ca produces significant stable isotope fractionation. The level of isotopic fractionation can provide key information about the variation in dietary consumption or Ca metabolism. To investigate this, we measured the 43 Ca/ 42 Ca and 44 Ca/ 42 Ca ratios for bone and blood plasma samples collected from mice of various ages using multiple collector-ICP-mass spectrometry (MC-ICP-MS). The 44 Ca/ 42 Ca ratio in bones was significantly (0.44 - 0.84 per mille) lower than the corresponding ratios in the diet, suggesting that Ca was isotopically fractionated during Ca metabolism for bone formation. The resulting 44 Ca/ 42 Ca ratios for blood plasma showed almost identical, or slightly higher, values (0.03 - 0.2 per mille) than found in a corresponding diet. This indicates that a significant amount of Ca in the blood plasma was from dietary sources. Unlike that discovered for Fe, there were not significant differences in the measured 44 Ca/ 42 Ca ratios between female and male specimens (for either bone or blood plasma samples). Similarity, the 44 Ca/ 42 Ca ratios suggests that there were no significant differences in Ca dietary consumption or Ca metabolism between female and male specimens. In contrast, the 44 Ca/ 42 Ca ratios of blood plasma from mother mice during the lactation period were significantly higher than those for all other adult specimens. This suggests that Ca supplied to infants through lactation was isotopically lighter, and the preferential supply of isotropically lighter Ca resulted in isotopically heavier Ca in blood plasma of mother mice during the lactation period. The data obtained here clearly demonstrate that the Ca isotopic ratio has a potential to become a new tool for evaluating changes in dietary consumption, or Ca metabolism of animals. (author)

Curating NASA's Past, Present, and Future Astromaterial Sample Collections

Science.gov (United States)

Zeigler, R. A.; Allton, J. H.; Evans, C. A.; Fries, M. D.; McCubbin, F. M.; Nakamura-Messenger, K.; Righter, K.; Zolensky, M.; Stansbery, E. K.

2016-01-01

The Astromaterials Acquisition and Curation Office at NASA Johnson Space Center (hereafter JSC curation) is responsible for curating all of NASA's extraterrestrial samples. JSC presently curates 9 different astromaterials collections in seven different clean-room suites: (1) Apollo Samples (ISO (International Standards Organization) class 6 + 7); (2) Antarctic Meteorites (ISO 6 + 7); (3) Cosmic Dust Particles (ISO 5); (4) Microparticle Impact Collection (ISO 7; formerly called Space-Exposed Hardware); (5) Genesis Solar Wind Atoms (ISO 4); (6) Stardust Comet Particles (ISO 5); (7) Stardust Interstellar Particles (ISO 5); (8) Hayabusa Asteroid Particles (ISO 5); (9) OSIRIS-REx Spacecraft Coupons and Witness Plates (ISO 7). Additional cleanrooms are currently being planned to house samples from two new collections, Hayabusa 2 (2021) and OSIRIS-REx (2023). In addition to the labs that house the samples, we maintain a wide variety of infra-structure facilities required to support the clean rooms: HEPA-filtered air-handling systems, ultrapure dry gaseous nitrogen systems, an ultrapure water system, and cleaning facilities to provide clean tools and equipment for the labs. We also have sample preparation facilities for making thin sections, microtome sections, and even focused ion-beam sections. We routinely monitor the cleanliness of our clean rooms and infrastructure systems, including measurements of inorganic or organic contamination, weekly airborne particle counts, compositional and isotopic monitoring of liquid N2 deliveries, and daily UPW system monitoring. In addition to the physical maintenance of the samples, we track within our databases the current and ever changing characteristics (weight, location, etc.) of more than 250,000 individually numbered samples across our various collections, as well as more than 100,000 images, and countless "analog" records that record the sample processing records of each individual sample. JSC Curation is co-located with JSC

Effect of sample matrix on the fundamental properties of the inductively coupled plasma

International Nuclear Information System (INIS)

Lehn, Scott A.; Warner, Kelly A.; Huang Mao; Hieftje, Gary M.

2003-01-01

In the inductively coupled plasma (ICP), the emission intensities of atomic and ionic spectral lines are controlled by fundamental parameters such as electron temperature, electron number density, gas-kinetic temperature, analyte atom and ion number densities, and others. Accordingly, the effect of a sample matrix on the analyte emission intensity in an ICP might be attributable to changes in these fundamental parameters caused by the matrix elements. In the present study, a plasma imaging instrument that combines Thomson scattering, Rayleigh scattering, laser-induced fluorescence and computed tomography has been employed to measure the above-mentioned parameters in the presence and absence of matrix elements. The data thus obtained were all collected on a spatially resolved basis and without the need for Abel inversion. Calcium, strontium and barium served as analytes, while lithium, copper and zinc were introduced as matrix elements. Comparing the data with and without the matrix elements allows us to determine the extent to which each fundamental parameter changes in the presence of a matrix element, and to better understand the nature of the matrix effects that occur in the ICP. As has been seen in previous studies with different matrix elements, ion emission and ion number densities follow opposite trends when matrix interferents are introduced into the plasma: ion emission is enhanced by the presence of matrix interferents while ion concentrations are lowered. These changes are consistent with a shift from collisional deactivation to radiative decay of excited-state analyte species

Effects of fusion relevant transient energetic radiation, plasma and thermal load on PLANSEE double forged tungsten samples in a low-energy plasma focus device

Science.gov (United States)

Javadi, S.; Ouyang, B.; Zhang, Z.; Ghoranneviss, M.; Salar Elahi, A.; Rawat, R. S.

2018-06-01

Tungsten is the leading candidate for plasma facing component (PFC) material for thermonuclear fusion reactors and various efforts are ongoing to evaluate its performance or response to intense fusion relevant radiation, plasma and thermal loads. This paper investigates the effects of hot dense decaying pinch plasma, highly energetic deuterium ions and fusion neutrons generated in a low-energy (3.0 kJ) plasma focus device on the structure, morphology and hardness of the PLANSEE double forged tungsten (W) samples surfaces. The tungsten samples were provided by Forschungszentrum Juelich (FZJ), Germany via International Atomic Energy Agency, Vienna, Austria. Tungsten samples were irradiated using different number of plasma focus (PF) shots (1, 5 and 10) at a fixed axial distance of 5 cm from the anode top and also at various distances from the top of the anode (5, 7, 9 and 11 cm) using fixed number (5) of plasma focus shots. The virgin tungsten sample had bcc structure (α-W phase). After PF irradiation, the XRD analysis showed (i) the presence of low intensity new diffraction peak corresponding to β-W phase at (211) crystalline plane indicating the partial structural phase transition in some of the samples, (ii) partial amorphization, and (iii) vacancy defects formation and compressive stress in irradiated tungsten samples. Field emission scanning electron microscopy showed the distinctive changes to non-uniform surface with nanometer sized particles and particle agglomerates along with large surface cracks at higher number of irradiation shots. X-ray photoelectron spectroscopy analysis demonstrated the reduction in relative tungsten oxide content and the increase in metallic tungsten after irradiation. Hardness of irradiated samples initially increased for one shot exposure due to reduction in tungsten oxide phase, but then decreased with increasing number of shots due to increasing concentration of defects. It is demonstrated that the plasma focus device provides

Plasma metanephrine for assessing the selectivity of adrenal venous sampling

NARCIS (Netherlands)

Dekkers, T.; Deinum, J.; Schultze Kool, L.J.; Blondin, D.; Vonend, O.; Hermus, A.R.M.M.; Peitzsch, M.; Rump, L.C.; Antoch, G.; Sweep, F.C.; Bornstein, S.R.; Lenders, J.W.M.; Willenberg, H.S.; Eisenhofer, G.

2013-01-01

Adrenal vein sampling is used to establish the origins of excess production of adrenal hormones in primary aldosteronism. Correct catheter positioning is confirmed using adrenal vein measurements of cortisol, but this parameter is not always reliable. Plasma metanephrine represents an alternative

Efficient discrimination and removal of phospholipids during electromembrane extraction from human plasma samples

DEFF Research Database (Denmark)

Vårdal, Linda; Gjelstad, Astrid; Huang, Chuixiu

2017-01-01

to be highly efficient for providing phospholipid-free extracts. CONCLUSION: Ultra-HPLC-MS/MS analysis of the donor solutions revealed that the phospholipids principally remained in the plasma samples. This proved that the phospholipids did not migrate in the electrical field and they were prevented from......AIM: For the first time, extracts obtained from human plasma samples by electromembrane extraction (EME) were investigated comprehensively with particular respect to phospholipids using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Thhe purpose...

Organic analysis of ambient samples collected near Tank 241-C-103: Results from samples collected on May 12, 1994

International Nuclear Information System (INIS)

Clauss, T.W.; Ligotke, M.W.; McVeety, B.D.; Lucke, R.B.; Young, J.S.; McCulloch, M.; Fruchter, J.S.; Goheen, S.C.

1995-06-01

This report describes organic analyses results from ambient samples collected both upwind and through the vapor sampling system (VSS) near Hanford waste storage Tank 241-C-103 (referred to as Tank C-103). The results described here were obtained to support safety and toxicological evaluations. A summary of the results for inorganic and organic analytes is listed. Quantitative results were obtained for organic compounds. Five organic tentatively identified compounds (TICS) were observed above the detection limit of (ca.) 10 ppbv, but standards for most of these were not available at the time of analysis, and the reported concentrations are semiquantitative estimates. In addition, we looked for the 40 standard TO-14 analytes. We observed 39. Of these, only one was observed above the 2-ppbv calibrated instrument detection limit. Dichloromethane was above the detection limits using both methods, but the result from the TO-14 method is traceable to a standard gas mixture and is considered more accurate. Organic analytes were found only in the sample collected through the VSS, suggesting that these compounds were residual contamination from a previous sampling job. Detailed descriptions of the results appear in the text

Ion collection by probing objects in flowing magnetized plasmas

International Nuclear Information System (INIS)

Kyu-Sun, Chung.

1989-04-01

A new one-dimensional collisionless kinetic model is developed for the flow of ions to probing structures in drifting plasmas. The cross-field flow into the presheath is modelled by accounting consistently for particle exchange between the collection flux tube and the outer plasma. Numerical solutions of the self-consistent plasma/sheath equations are obtained with arbitrary external ion temperature and parallel plasma flow velocity. Results are presented of the spatial dependence of the ion distribution function as well as its moments (density, particle flux, temperature, and power flux). The ion current to the probe is obtained and the ratio of the upstream to downstream currents is found to be well represented by the form R = exp[Ku d ], where K = 1.66 for T i = T e and u d is the drift velocity in units of (T e /m i ) 1/2 . The results agree well with comparable recent fluid calculations but show substantial deviations from other models which ignore particle exchange out of the presheath. No evidence is found of the formation of shocks in the downstream wake, contrary to the implications of some fluid theories. We have also extended the previous kinetic model by generalizing cross-field transport and adding ionization to the source of the Boltzmann equation along the presheath. Ion sheath current density and ratio(R) of upstream to downstream current are obtained as a function of plasma drift velocity, equivalent viscosity, ion temperature, and ionization rate. Constants(K) in the form R = exp[Ku d ] are obtained in terms of viscosity, ion temperature, and ionization rate. The effect of an electrical bias applied to the object on the presheath characteristics is discussed

Influence of sample temperature on the expansion dynamics and the optical emission of laser-induced plasma

Energy Technology Data Exchange (ETDEWEB)

Eschlböck-Fuchs, S.; Haslinger, M.J.; Hinterreiter, A.; Kolmhofer, P.; Huber, N. [Christian Doppler Laboratory for Laser-Assisted Diagnostics, Institute of Applied Physics, Johannes Kepler University Linz, A-4040 Linz (Austria); Rössler, R. [voestalpine Stahl GmbH, A-4031 Linz (Austria); Heitz, J. [Christian Doppler Laboratory for Laser-Assisted Diagnostics, Institute of Applied Physics, Johannes Kepler University Linz, A-4040 Linz (Austria); Pedarnig, J.D., E-mail: johannes.pedarnig@jku.at [Christian Doppler Laboratory for Laser-Assisted Diagnostics, Institute of Applied Physics, Johannes Kepler University Linz, A-4040 Linz (Austria)

2013-09-01

We investigate the influence of sample temperature on the dynamics and optical emission of laser induced plasma for various solid materials. Bulk aluminum alloy, silicon wafer, and metallurgical slag samples are heated to temperature T{sub S} ≤ 500 °C and ablated in air by Nd:YAG laser pulses (wavelength 1064 nm, pulse duration approx. 7 ns). The plasma dynamics is investigated by fast time-resolved photography. For laser-induced breakdown spectroscopy (LIBS) the optical emission of plasma is measured by Echelle spectrometers in combination with intensified CCD cameras. For all sample materials the temporal evolution of plume size and broadband plasma emission vary systematically with T{sub S}. The size and brightness of expanding plumes increase at higher T{sub S} while the mean intensity remains independent of temperature. The intensity of emission lines increases with temperature for all samples. Plasma temperature and electron number density do not vary with T{sub S}. We apply the calibration-free LIBS method to determine the concentration of major oxides in slag and find good agreement to reference data up to T{sub S} = 450 °C. The LIBS analysis of multi-component materials at high temperature is of interest for technical applications, e.g. in industrial production processes. - Highlights: • Size and emission of laser-induced plasma increase with sample temperature Ts. • Mean optical intensity of plasma is independent of Ts. • Plasma temperature and electron number density do not vary with Ts. • Major oxides in steel slag are quantified up to Ts = 450 °C. • Industrial steel slags are analyzed by calibration-free LIBS method.

Velocity-space tomography of fusion plasmas by collective Thomson scattering of gyrotron radiation

DEFF Research Database (Denmark)

Salewski, Mirko; Jacobsen, A.S.; Jensen, Thomas

2016-01-01

-tonoise ratio becomes fairly low for MeV-range ions. Ions at any energy can be detected well by collective Thomson scattering of mm-wave radiation from a high-power gyrotron. We demonstrate how collective Thomson scattering can be used to measure 푓2퐷푣 in the MeV-range in reactor relevant plasmas...

Methods for the collection of subsurface samples during environmental site assessments

International Nuclear Information System (INIS)

Weinstock, E.A.

1996-01-01

This paper discusses numerous sample collection techniques that have been successfully employed during Phase 2 Assessments and presents case histories of their application. Pollutants of concern include PCE and petroleum. The collection of shallow soil samples is described using commercially available hand augers and hand-driven core samplers. These devices are modified with extensions to collect deeper samples from storm drains and leaching pools. The performance of soil gas surveys are described using both hand-driven sample probes and vehicle-mounted, hydraulically driven vapor probes. Once the soil vapor is collected at the ground surface, a sample of the media is either analyzed on-site using a field-operated detection device or delivered to a laboratory for analysis. Application and case histories of the Geoprobe(trademark)sampling system, a form of direct push technology, are described. This device uses vehicle-mounted, hydraulically-driven sample probes. The probe can be advanced to depths as great as 100 feet below grade and can retrieve soil, soil gas and groundwater samples

The Spectral Emission Characteristics of Laser Induced Plasma on Tea Samples

International Nuclear Information System (INIS)

Zheng Peichao; Shi Minjie; Wang Jinmei; Liu Hongdi

2015-01-01

Laser induced breakdown spectroscopy (LIBS) provides a useful technique for food security as well as determining nutrition contents. In this paper, optical emission studies of laser induced plasma on commercial tea samples were carried out. The spectral intensities of Mg, Mn, Ca, Al, C and CN vibration bands varying with laser energy and the detection delay time of an intensified charge coupled device were studied. In addition, the relative concentrations of six microelements, i.e., Mg, Mn, Ca, Al, Na and K, were analyzed semi-quantitatively as well as H, for four kinds of tea samples. Moreover, the plasma parameters were explored, including electron temperature and electron number density. The electron temperature and electron number density were around 11000 K and 10 17 cm −3 , respectively. The results show that it is reasonable to consider the LIBS technique as a new method for analyzing the compositions of tea leaf samples. (paper)

Importance of sampling frequency when collecting diatoms

KAUST Repository

Wu, Naicheng; Faber, Claas; Sun, Xiuming; Qu, Yueming; Wang, Chao; Ivetic, Snjezana; Riis, Tenna; Ulrich, Uta; Fohrer, Nicola

2016-01-01

There has been increasing interest in diatom-based bio-assessment but we still lack a comprehensive understanding of how to capture diatoms’ temporal dynamics with an appropriate sampling frequency (ASF). To cover this research gap, we collected

Limited sampling strategy for determining metformin area under the plasma concentration-time curve

DEFF Research Database (Denmark)

Santoro, Ana Beatriz; Stage, Tore Bjerregaard; Struchiner, Claudio José

2016-01-01

AIM: The aim was to develop and validate limited sampling strategy (LSS) models to predict the area under the plasma concentration-time curve (AUC) for metformin. METHODS: Metformin plasma concentrations (n = 627) at 0-24 h after a single 500 mg dose were used for LSS development, based on all su...

Protocol for collecting eDNA samples from streams [Version 2.3

Science.gov (United States)

K. J. Carim; T. Wilcox; M. K. Young; K. S. McKelvey; M. K. Schwartz

2015-01-01

Throughout the 2014 field season, we had over two dozen biologist throughout the western US collect over 300 samples for eDNA analysis with paired controls. Control samples were collected by filtering 0.5 L of distilled water. No samples had any evidence of field contamination. This method of sampling verifies the cleanliness of the field equipment, as well as the...

Comparison of digoxin concentration in plastic serum tubes with clot activator and heparinized plasma tubes.

Science.gov (United States)

Dukić, Lora; Simundić, Ana-Maria; Malogorski, Davorin

2014-01-01

Sample type recommended by the manufacturer for the digoxin Abbott assay is either serum collected in glass tubes or plasma (sodium heparin, lithium heparin, citrate, EDTA or oxalate as anticoagulant) collected in plastic tubes. In our hospital samples are collected in plastic tubes. Our hypothesis was that the serum sample collected in plastic serum tube can be used interchangeably with plasma sample for measurement of digoxin concentration. Our aim was verification of plastic serum tubes for determination of digoxin concentration. Concentration of digoxin was determined simultaneously in 26 venous blood plasma (plastic Vacuette, LH Lithium heparin) and serum (plastic Vacuette, Z Serum Clot activator; both Greiner Bio-One GmbH, Kremsmünster, Austria) samples, on Abbott AxSYM analyzer using the original Abbott Digoxin III assay (Abbott, Wiesbaden, Germany). Tube comparability was assessed using the Passing Bablok regression and Bland-Altman plot. Serum and plasma digoxin concentrations are comparable. Passing Bablok intercept (0.08 [95% CI = -0.10 to 0.20]) and slope (0.99 [95% CI = 0.92 to 1.11]) showed there is no constant or proportional error. Blood samples drawn in plastic serum tubes and plastic plasma tubes can be interchangeably used for determination of digoxin concentration.

Sample collection and sample analysis plan in support of the 105-C/190-C concrete and soil sampling activities

International Nuclear Information System (INIS)

Marske, S.G.

1996-07-01

This sampling and analysis plan describes the sample collection and sample analysis in support of the 105-C water tunnels and 190-C main pumphouse concrete and soil sampling activities. These analytical data will be used to identify the radiological contamination and presence of hazardous materials to support the decontamination and disposal activities

Etching of Niobium Sample Placed on Superconducting Radio Frequency Cavity Surface in Ar/CL2 Plasma

International Nuclear Information System (INIS)

Upadhyay, Janardan; Phillips, Larry; Valente, Anne-Marie

2011-01-01

Plasma based surface modification is a promising alternative to wet etching of superconducting radio frequency (SRF) cavities. It has been proven with flat samples that the bulk Niobium (Nb) removal rate and the surface roughness after the plasma etchings are equal to or better than wet etching processes. To optimize the plasma parameters, we are using a single cell cavity with 20 sample holders symmetrically distributed over the cell. These holders serve the purpose of diagnostic ports for the measurement of the plasma parameters and for the holding of the Nb sample to be etched. The plasma properties at RF (100 MHz) and MW (2.45 GHz) frequencies are being measured with the help of electrical and optical probes at different pressures and RF power levels inside of this cavity. The niobium coupons placed on several holders around the cell are being etched simultaneously. The etching results will be presented at this conference.

Etching of Niobium Sample Placed on Superconducting Radio Frequency Cavity Surface in Ar/CL2 Plasma

Energy Technology Data Exchange (ETDEWEB)

Janardan Upadhyay, Larry Phillips, Anne-Marie Valente

2011-09-01

Plasma based surface modification is a promising alternative to wet etching of superconducting radio frequency (SRF) cavities. It has been proven with flat samples that the bulk Niobium (Nb) removal rate and the surface roughness after the plasma etchings are equal to or better than wet etching processes. To optimize the plasma parameters, we are using a single cell cavity with 20 sample holders symmetrically distributed over the cell. These holders serve the purpose of diagnostic ports for the measurement of the plasma parameters and for the holding of the Nb sample to be etched. The plasma properties at RF (100 MHz) and MW (2.45 GHz) frequencies are being measured with the help of electrical and optical probes at different pressures and RF power levels inside of this cavity. The niobium coupons placed on several holders around the cell are being etched simultaneously. The etching results will be presented at this conference.

Enriched lithium collection from lithium plasma flow

International Nuclear Information System (INIS)

Karchevsky, A.I.; Laz'ko, V.S.; Muromkin, Y.A.; Pashkovsky, V.G.; Ustinov, A.L.; Dolgolenko, D.A.

1994-01-01

In order to understand the physical processes concerned with the selective heating by ion cyclotron resonance and with the subsequent collection of heated particles, experiments were carried out with the extraction of lithium samples, enriched with 6 Li isotopes. Probe and integral extractors allow to collect enriched Li at the end of the selective heating region. Surface density distribution on the collector and local isotopic content of lithium are measured, as a function of the screen height and the retarding potential. Dependence of the collected amount of lithium and of its isotopic content on the value of the magnetic field is also measured. 4 figs., 2 tabs., 5 refs

Sample Preparation Report of the Fourth OPCW Confidence Building Exercise on Biomedical Sample Analysis

Energy Technology Data Exchange (ETDEWEB)

Udey, R. N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Corzett, T. H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Alcaraz, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2014-07-03

Following the successful completion of the 3rd biomedical confidence building exercise (February 2013 – March 2013), which included the analysis of plasma and urine samples spiked at low ppb levels as part of the exercise scenario, another confidence building exercise was targeted to be conducted in 2014. In this 4th exercise, it was desired to focus specifically on the analysis of plasma samples. The scenario was designed as an investigation of an alleged use of chemical weapons where plasma samples were collected, as plasma has been reported to contain CWA adducts which remain present in the human body for several weeks (Solano et al. 2008). In the 3rd exercise most participants used the fluoride regeneration method to analyze for the presence of nerve agents in plasma samples. For the 4th biomedical exercise it was decided to evaluate the analysis of human plasma samples for the presence/absence of the VX adducts and aged adducts to blood proteins (e.g., VX-butyrylcholinesterase (BuChE) and aged BuChE adducts using a pepsin digest technique to yield nonapeptides; or equivalent). As the aging of VX-BuChE adducts is relatively slow (t1/2 = 77 hr at 37 °C [Aurbek et al. 2009]), soman (GD), which ages much more quickly (t1/2 = 9 min at 37 °C [Masson et al. 2010]), was used to simulate an aged VX sample. Additional objectives of this exercise included having laboratories assess novel OP-adducted plasma sample preparation techniques and analytical instrumentation methodologies, as well as refining/designating the reporting formats for these new techniques.

Quality standards for sample collection in coagulation testing.

Science.gov (United States)

Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Lima-Oliveira, Gabriel; Guidi, Gian Cesare; Favaloro, Emmanuel J

2012-09-01

Preanalytical activities, especially those directly connected with blood sample collection and handling, are the most vulnerable steps throughout the testing process. The receipt of unsuitable samples is commonplace in laboratory practice and represents a serious problem, given the reliability of test results can be adversely compromised following analysis of these specimens. The basic criteria for an appropriate and safe venipuncture are nearly identical to those used for collecting blood for clinical chemistry and immunochemistry testing, and entail proper patient identification, use of the correct technique, as well as appropriate devices and needles. There are, however, some peculiar aspects, which are deemed to be particularly critical when collecting quality specimens for clot-based tests, and these require clearer recognition. These include prevention of prolonged venous stasis, collection of nonhemolyzed specimens, order of draw, and appropriate filling and mixing of the primary collection tubes. All of these important preanalytical issues are discussed in this article, and evidence-based suggestions as well as recommendations on how to obtain a high-quality sample for coagulation testing are also illustrated. We have also performed an investigation aimed to identify variation of test results due to underfilling of primary blood tubes, and have identified a clinically significant bias in test results when tubes are drawn at less than 89% of total fill for activated partial thromboplastin time, less than 78% for fibrinogen, and less than 67% for coagulation factor VIII, whereas prothrombin time and activated protein C resistance remain relatively reliable even in tubes drawn at 67% of the nominal volume. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Plasma catecholamines and plasma corticosterone following restraint stress in juvenile alligators.

Science.gov (United States)

Lance, V A; Elsey, R M

1999-05-01

Ten juvenile alligators, mean body mass 793 g, hatched from artificially incubated eggs and raised under controlled conditions, were held out of water with their jaws held closed for 48 hr. An initial blood sample was taken and further samples collected at 1, 2, 4, 8, 24, and 48 hr. Epinephrine, norepinephrine, and dopamine were measured in plasma aliquots of 1.5 ml using high pressure liquid chromatography with electrochemical detection. Corticosterone was measured by radioimmunoassay. Plasma glucose was measured using the Trinder method and plasma calcium, cholesterol, and triglycerides were measured in an autoanalyzer. Epinephrine was about 4 ng/ml at the initial bleed, but declined steadily to blood cells showed changes indicating immune system suppression. By the end of the treatment the hetorophil/lymphocyte ratio increased to 4.7. These results suggest that handling alligators, taking multiple blood samples, and keeping them restrained for more than 8 hr is a severe stress to the animals.

Rapid determination of piracetam in human plasma and cerebrospinal fluid by micellar electrokinetic chromatography with sample direct injection.

Science.gov (United States)

Yeh, Hsin-Hua; Yang, Yuan-Han; Ko, Ju-Yun; Chen, Su-Hwei

2006-07-07

A simple micellar electrokinetic chromatography (MEKC) method with UV detection at 200 nm for analysis of piracetam in plasma and in cerebrospinal fluid (CSF) by direct injection without any sample pretreatment is described. The separation of piracetam from biological matrix was performed at 25 degrees C using a background electrolyte consisting of Tris buffer with sodium dodecyl sulfate (SDS) as the electrolyte solution. Several parameters affecting the separation of the drug from biological matrix were studied, including the pH and concentrations of the Tris buffer and SDS. Under optimal MEKC condition, good separation with high efficiency and short analyses time is achieved. Using imidazole as an internal standard (IS), the linear ranges of the method for the determination of piracetam in plasma and in CSF were all between 5 and 500 microg/mL; the detection limit of the drug in plasma and in CSF (signal-to-noise ratio=3; injection 0.5 psi, 5s) was 1.0 microg/mL. The applicability of the proposed method for determination of piracetam in plasma and CSF collected after intravenous administration of 3g piracetam every 6h and oral administration 1.2g every 6h in encephalopathy patients with aphasia was demonstrated.

Determination of uranium from nuclear fuel in environmental samples using inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Boulyga, S.F.; Becker, J.S.

2000-01-01

As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The 236 U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on inductively coupled plasma quadrupole mass spectrometry with a hexapole collision cell (HEX-ICP-QMS). The figures of merit of the HEX-ICP-QMS were studied with a plasma-shielded torch using different nebulizers (such as an ultrasonic nebulizer (USN) and Meinhard nebulizer) for solution introduction. A 238 U + ion intensity of up to 27000 MHz/ppm in HEX-ICP-QMS with USN was observed by introducing helium into the hexapole collision cell as the collision gas at a flow rate of 10 ml min -1 . The formation rate of uranium hydride ions UH + /U + of 2 x 10 -6 was obtained by using USN with a membrane desolvator. The limit of 236 U/ 238 U ratio determination in 10 μg 1 -1 uranium solution was 3 x 10 -7 corresponding to the detection limit for 236 U of 3 pg 1 -1 . The precision of uranium isotopic ratio measurements in 10 μg 1 -1 laboratory uranium isotopic standard solution was 0.13% ( 235 U/ 238 U) and 0.33% ( 236 U/ 238 U) using a Meinhard nebulizer and 0.45% ( 235 U/ 238 U) and 0.88% ( 236 U/ 238 U) using a USN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the 236 U/ 238 U ratio ranged from 10 -5 to 10 -3 . (orig.)

Principles of fuel ion ratio measurements in fusion plasmas by collective Thomson scattering

DEFF Research Database (Denmark)

Stejner Pedersen, Morten; Nielsen, Stefan Kragh; Bindslev, Henrik

2011-01-01

ratio. Measurements of the fuel ion ratio will be important for plasma control and machine protection in future experiments with burning fusion plasmas. Here we examine the theoretical basis for fuel ion ratio measurements by CTS. We show that the sensitivity to plasma composition is enhanced......For certain scattering geometries collective Thomson scattering (CTS) measurements are sensitive to the composition of magnetically confined fusion plasmas. CTS therefore holds the potential to become a new diagnostic for measurements of the fuel ion ratio—i.e. the tritium to deuterium density...... by the signatures of ion cyclotron motion and ion Bernstein waves which appear for scattering geometries with resolved wave vectors near perpendicular to the magnetic field. We investigate the origin and properties of these features in CTS spectra and give estimates of their relative importance for fuel ion ratio...

Quantification of isotope-labelled and unlabelled folates in plasma, ileostomy and food samples.

Science.gov (United States)

Büttner, Barbara E; Öhrvik, Veronica E; Witthöft, Cornelia M; Rychlik, Michael

2011-01-01

New stable isotope dilution assays were developed for the simultaneous quantitation of [(13)C(5)]-labelled and unlabelled 5-methyltetrahydrofolic acid, 5-formyltetrahydrofolic acid, folic acid along with unlabelled tetrahydrofolic acid and 10-formylfolic acid in clinical samples deriving from human bioavailability studies, i.e. plasma, ileostomy samples, and food. The methods were based on clean-up by strong anion exchange followed by LC-MS/MS detection. Deuterated analogues of the folates were applied as the internal standards in the stable isotope dilution assays. Assay sensitivity was sufficient to detect all relevant folates in the respective samples as their limits of detection were below 0.62 nmol/L in plasma and below 0.73 μg/100 g in food or ileostomy samples. Quantification of the [(13)C(5)]-label in clinical samples offers the possibility to differentiate between folate from endogenous body pools and the administered dose when executing bioavailability trials.

Standardized Method for Measuring Collection Efficiency from Wipe-sampling of Trace Explosives.

Science.gov (United States)

Verkouteren, Jennifer R; Lawrence, Jeffrey A; Staymates, Matthew E; Sisco, Edward

2017-04-10

One of the limiting steps to detecting traces of explosives at screening venues is effective collection of the sample. Wipe-sampling is the most common procedure for collecting traces of explosives, and standardized measurements of collection efficiency are needed to evaluate and optimize sampling protocols. The approach described here is designed to provide this measurement infrastructure, and controls most of the factors known to be relevant to wipe-sampling. Three critical factors (the applied force, travel distance, and travel speed) are controlled using an automated device. Test surfaces are chosen based on similarity to the screening environment, and the wipes can be made from any material considered for use in wipe-sampling. Particle samples of the explosive 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) are applied in a fixed location on the surface using a dry-transfer technique. The particle samples, recently developed to simulate residues made after handling explosives, are produced by inkjet printing of RDX solutions onto polytetrafluoroethylene (PTFE) substrates. Collection efficiency is measured by extracting collected explosive from the wipe, and then related to critical sampling factors and the selection of wipe material and test surface. These measurements are meant to guide the development of sampling protocols at screening venues, where speed and throughput are primary considerations.

Multi-element analyses of Vietnamese environmental samples for radiation protection

International Nuclear Information System (INIS)

Mai, T.H.; Nguyen, T.B.; Nguyen, T.N.; Yoshida, S.

2005-01-01

The Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) were used for measuring 8 major and 27 trace elements in food and soil samples collected in Vietnam. The concentration of elements in food samples was different from different locations and also from different food groups. Depth profiles of the elements were discussed for soil samples. (author)

General principles for the formation of dust self-organizing structures. Dust collective attraction and plasma crystal formation

International Nuclear Information System (INIS)

Tsytovich, V.N.

2005-01-01

It is demonstrated that a homogeneous dusty plasma is universally unstable to form structures. The effect of collective grain attraction is a basic phenomenon for the proposed new paradigm (general principles) for the plasma crystal formation

Detection of drugs of abuse in exhaled breath using a device for rapid collection: comparison with plasma, urine and self-reporting in 47 drug users.

Science.gov (United States)

Beck, Olof; Stephanson, Niclas; Sandqvist, Sören; Franck, Johan

2013-06-01

Exhaled breath has recently been identified as a matrix for the detection of drugs of abuse. This work aims to further document this application using a new and simple collection device in patients following recovery from acute intoxication. Breath, plasma and urine samples were collected from 47 patients (38 males, age range 25-74) together with interview data. Analysis of breath and plasma samples was done by liquid chromatography-mass spectrometry methods. Urine was screened using immunochemical reagents and positive findings confirmed with liquid chromatography-mass spectrometry methods. The 12 analytes investigated were: methadone, amphetamine, methamphetamine, 6-acetylmorphine, morphine, benzoylecgonine, cocaine, diazepam, oxazepam, alprazolam, buprenorphine and tetrahydrocannabinol. In all 47 cases, recent intake of an abused substance prior to admission was reported, but in one case the substance (ketobemidone) was not investigated. In 40 of the remaining cases (87%) breath analysis gave a positive finding of any of the substances that were part of the analytical investigation. Identifications were based on correct chromatographic retention time and product ion ratios obtained in selected reaction monitoring mode. In general, data from breath, plasma, urine and self-reporting were in good agreement, but in 23% of the cases substances were detected that had not been self-reported. All substances covered were detected in a number of breath samples. Considering that breath sampling was often done about 24 h after intake, the detection rate was considered to be high for most substances. Analytes with low detection rates were benzodiazepines, and a further increase in analytical sensitivity is needed to overcome this. This study further supports use of exhaled breath as a new matrix in clinical toxicology.

Association of plasma homocysteine and white matter hypodensities in a sample of stroke patients

International Nuclear Information System (INIS)

Naveed, G.

2015-01-01

Studies of homocysteine in vascular disorders have yielded conflicting data. There are also differences based on various ethnicities and cultures. In this study, we have examined the homocysteine patterns in local stroke patients, so as to ascertain the homocysteine status in a sample of local population. Homocysteine-white matter hypodensities relationship in stroke is emerging, as an important aspect in stroke pathophysiology and is thought to have prognostic and therapeutic values. Methods: We included 150 stroke patients who were diagnosed as having clinical stroke on the basis of history; physical examination and CT (Computerized Tomography) scan of brain. These patients were recruited from neurology and emergency wards of two public sector hospitals of Lahore. The presence or absence of white matter hypodensities were diagnosed after consultation with a radiologist. Blood samples were collected from the same stroke patients. Results: We found a strong association between white matter hypodensities and total homocysteine in plasma of stroke patients p<0.001. Conclusion: Homocysteine is a risk factor for white matter hypodensities in stroke patients in our study. (author)

Self-collected versus clinician-collected sampling for sexually transmitted infections: a systematic review and meta-analysis protocol.

Science.gov (United States)

Taylor, Darlene; Lunny, Carole; Wong, Tom; Gilbert, Mark; Li, Neville; Lester, Richard; Krajden, Mel; Hoang, Linda; Ogilvie, Gina

2013-10-10

Three meta-analyses and one systematic review have been conducted on the question of whether self-collected specimens are as accurate as clinician-collected specimens for STI screening. However, these reviews predate 2007 and did not analyze rectal or pharyngeal collection sites. Currently, there is no consensus on which sampling method is the most effective for the diagnosis of genital chlamydia (CT), gonorrhea (GC) or human papillomavirus (HPV) infection. Our meta-analysis aims to be comprehensive in that it will examine the evidence of whether self-collected vaginal, urine, pharyngeal and rectal specimens provide as accurate a clinical diagnosis as clinician-collected samples (reference standard). Eligible studies include both randomized and non-randomized controlled trials, pre- and post-test designs, and controlled observational studies. The databases that will be searched include the Cochrane Database of Systematic Reviews, Web of Science, Database of Abstracts of Reviews of Effects (DARE), EMBASE and PubMed/Medline. Data will be abstracted independently by two reviewers using a standardized pre-tested data abstraction form. Heterogeneity will be assessed using the Q2 test. Sensitivity and specificity estimates with 95% confidence intervals as well as negative and positive likelihood ratios will be pooled and weighted using random effects meta-analysis, if appropriate. A hierarchical summary receiver operating characteristics curve for self-collected specimens will be generated. This synthesis involves a meta-analysis of self-collected samples (urine, vaginal, pharyngeal and rectal swabs) versus clinician-collected samples for the diagnosis of CT, GC and HPV, the most prevalent STIs. Our systematic review will allow patients, clinicians and researchers to determine the diagnostic accuracy of specimens collected by patients compared to those collected by clinicians in the detection of chlamydia, gonorrhea and HPV.

Plasma Levels of Middle Molecules to Estimate Residual Kidney Function in Haemodialysis without Urine Collection.

Directory of Open Access Journals (Sweden)

Enric Vilar

Full Text Available Residual Kidney Function (RKF is associated with survival benefits in haemodialysis (HD but is difficult to measure without urine collection. Middle molecules such as Cystatin C and β2-microglobulin accumulate in renal disease and plasma levels have been used to estimate kidney function early in this condition. We investigated their use to estimate RKF in patients on HD.Cystatin C, β2-microglobulin, urea and creatinine levels were studied in patients on incremental high-flux HD or hemodiafiltration(HDF. Over sequential HD sessions, blood was sampled pre- and post-session 1 and pre-session 2, for estimation of these parameters. Urine was collected during the whole interdialytic interval, for estimation of residual GFR (GFRResidual = mean of urea and creatinine clearance. The relationships of plasma Cystatin C and β2-microglobulin levels to GFRResidual and urea clearance were determined.Of the 341 patients studied, 64% had urine output>100 ml/day, 32.6% were on high-flux HD and 67.4% on HDF. Parameters most closely correlated with GFRResidual were 1/β2-micoglobulin (r2 0.67 and 1/Cystatin C (r2 0.50. Both these relationships were weaker at low GFRResidual. The best regression model for GFRResidual, explaining 67% of the variation, was: GFRResidual = 160.3 · (1/β2m - 4.2. Where β2m is the pre-dialysis β2 microglobulin concentration (mg/L. This model was validated in a separate cohort of 50 patients using Bland-Altman analysis. Areas under the curve in Receiver Operating Characteristic analysis aimed at identifying subjects with urea clearance≥2 ml/min/1.73 m2 was 0.91 for β2-microglobulin and 0.86 for Cystatin C. A plasma β2-microglobulin cut-off of ≤19.2 mg/L allowed identification of patients with urea clearance ≥2 ml/min/1.73 m2 with 90% specificity and 65% sensitivity.Plasma pre-dialysis β2-microglobulin levels can provide estimates of RKF which may have clinical utility and appear superior to cystatin C. Use of cut-off levels

Collective phenomena in the non-equilibrium quark-gluon plasma

Energy Technology Data Exchange (ETDEWEB)

Schenke, Bjoern Peter

2008-07-03

In this work we study the non-equilibrium dynamics of a quark-gluon plasma, as created in heavy-ion collisions. We investigate how big of a role plasma instabilities can play in the isotropization and equilibration of a quark-gluon plasma. In particular, we determine, among other things, how much collisions between the particles can reduce the growth rate of unstable modes. This is done both in a model calculation using the hard-loop approximation, as well as in a real-time lattice simulation combining both classical Yang-Mills-fields as well as inter-particle collisions. The new extended version of the simulation is also used to investigate jet transport in isotropic media, leading to a cutoff-independent result for the transport coefficient q. The precise determination of such transport coefficients is essential, since they can provide important information about the medium created in heavy ion collisions. In anisotropic media, the effect of instabilities on jet transport is studied, leading to a possible explanation for the experimental observation that high-energy jets traversing the plasma perpendicular to the beam axis experience much stronger broadening in rapidity than in azimuth. The investigation of collective modes in the hard-loop limit is extended to fermionic modes, which are shown to be all stable. Finally, we study the possibility of using high energy photon production as a tool to experimentally determine the anisotropy of the created system. Knowledge of the degree of local momentum-space anisotropy reached in a heavy-ion collision is essential for the study of instabilities and their role for isotropization and thermalization, because their growth rate depends strongly on the anisotropy. (orig.)

Collective modes of the quantum one-component plasma in a magnetic field

NARCIS (Netherlands)

John, P.; Suttorp, L.G.

1993-01-01

The authors derive the collective modes of a quantum one-component plasma in a magnetic field by using a projection operator technique. With the help of these modes the long-time behaviour of the time correlation functions for the charge density, the current density and the energy density is

Soil sample collection and analysis for the Fugitive Dust Characterization Study

Science.gov (United States)

Ashbaugh, Lowell L.; Carvacho, Omar F.; Brown, Michael S.; Chow, Judith C.; Watson, John G.; Magliano, Karen C.

A unique set of soil samples was collected as part of the Fugitive Dust Characterization Study. The study was carried out to establish whether or not source profiles could be constructed using novel analytical methods that could distinguish soil dust sources from each other. The soil sources sampled included fields planted in cotton, almond, tomato, grape, and safflower, dairy and feedlot facilities, paved and unpaved roads (both urban and rural), an agricultural staging area, disturbed land with salt buildup, and construction areas where the topsoil had been removed. The samples were collected using a systematic procedure designed to reduce sampling bias, and were stored frozen to preserve possible organic signatures. For this paper the samples were characterized by particle size (percent sand, silt, and clay), dry silt content (used in EPA-recommended fugitive dust emission factors), carbon and nitrogen content, and potential to emit both PM 10 and PM 2.5. These are not the "novel analytical methods" referred to above; rather, it was the basic characterization of the samples to use in comparing analytical methods by other scientists contracted to the California Air Resources Board. The purpose of this paper is to document the methods used to collect the samples, the collection locations, the analysis of soil type and potential to emit PM 10, and the sample variability, both within field and between fields of the same crop type.

Collection of biological samples in forensic toxicology.

Science.gov (United States)

Dinis-Oliveira, R J; Carvalho, F; Duarte, J A; Remião, F; Marques, A; Santos, A; Magalhães, T

2010-09-01

Forensic toxicology is the study and practice of the application of toxicology to the purposes of the law. The relevance of any finding is determined, in the first instance, by the nature and integrity of the specimen(s) submitted for analysis. This means that there are several specific challenges to select and collect specimens for ante-mortem and post-mortem toxicology investigation. Post-mortem specimens may be numerous and can endow some special difficulties compared to clinical specimens, namely those resulting from autolytic and putrefactive changes. Storage stability is also an important issue to be considered during the pre-analytic phase, since its consideration should facilitate the assessment of sample quality and the analytical result obtained from that sample. The knowledge on degradation mechanisms and methods to increase storage stability may enable the forensic toxicologist to circumvent possible difficulties. Therefore, advantages and limitations of specimen preservation procedures are thoroughfully discussed in this review. Presently, harmonized protocols for sampling in suspected intoxications would have obvious utility. In the present article an overview is given on sampling procedures for routinely collected specimens as well as on alternative specimens that may provide additional information on the route and timing of exposure to a specific xenobiotic. Last, but not least, a discussion on possible bias that can influence the interpretation of toxicological results is provided. This comprehensive review article is intented as a significant help for forensic toxicologists to accomplish their frequently overwhelming mission.

Ion-collecting sphere in a stationary, weakly magnetized plasma with finite shielding length

International Nuclear Information System (INIS)

Patacchini, Leonardo; Hutchinson, Ian H

2007-01-01

Collisionless ion collection by a negatively biased stationary spherical probe in a finite shielding length plasma is investigated using the Particle in Cell code SCEPTIC, in the presence of a weak magnetic field B. The overall effect of the magnetic field is to reduce the ion current, linearly in |B| for weak enough fields, with a slope steepness increasing with the electron Debye length. The angular current distribution and space-charge buildup strongly depend on the focusing properties of the probe, hence on its potential and the plasma shielding length. In particular, it is found that the concavity of the ion collection flux distribution can reverse sign when the electron Debye length is comparable to or larger than the probe radius (λ De ∼> r p ), provided the ion temperature is much lower than the probe bias (T i p )

Mineral profiling of ostrich (Struthio camelus) seminal plasma and its relationship with semen traits and collection day.

Science.gov (United States)

Smith, A M J; Bonato, M; Dzama, K; Malecki, I A; Cloete, S W P

2018-06-01

Successful assisted reproduction techniques, with specific focus on in vitro semen storage for artificial insemination, are dependent on certain key elements which includes the biochemical profiling of semen. The objective of this study was to complete an ostrich seminal plasma (SP) evaluation by inductively coupled plasma mass spectrometry (ICP-MS) among seven males at different daily intervals (day 1, 3, 7, 11, 15, 19, 21, 23, 25, 26, 27, 28) for a period of 28 days during spring (August to September) for mineral profiling. The effect of collection day and male on sperm concentration, semen volume and seminal plasma volume, was explored as well as the relationships amongst these specific sperm traits and SP minerals. Variation amongst SP mineral concentrations, accounted for by the fixed effects of sperm concentration, semen volume, seminal plasma volume, collection day and male, ranged from 18% to 77%. Male had the largest effect on variation in SP minerals, namely: phosphorus (P), potassium (K), calcium (Ca), sodium (Na), boron (B), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), molybdenum (Mo), barium (Ba), arsenic (As) and selenium (Se). Sperm concentration instigated fluctuations of P, magnesium (Mg), B, zinc (Zn), Fe, aluminium (Al), Se, manganese (Mn) and lead (Pb). Semen volume had an effect on Na, K, B, Pb and Ba while seminal plasma volume only influenced variation in Na. There were fluctuations among collection days of specific micro minerals, Ni and Mo, with initial Ni concentrations being relatively greater and Mo at lesser concentrations. Semen volume, seminal plasma volume and sperm concentration varied amongst males. Sperm concentrations during the initial collection days, 1 and 3, were less than that for days 7 to 28. Significant variation of SP minerals and sperm characteristics among ejaculates and males suggest an association of these specific elements with sperm function and are, therefore, considered to be of potential importance to

Fluid sample collection and distribution system. [qualitative analysis of aqueous samples from several points

Science.gov (United States)

Brooks, R. L. (Inventor)

1979-01-01

A multipoint fluid sample collection and distribution system is provided wherein the sample inputs are made through one or more of a number of sampling valves to a progressive cavity pump which is not susceptible to damage by large unfiltered particles. The pump output is through a filter unit that can provide a filtered multipoint sample. An unfiltered multipoint sample is also provided. An effluent sample can be taken and applied to a second progressive cavity pump for pumping to a filter unit that can provide one or more filtered effluent samples. The second pump can also provide an unfiltered effluent sample. Means are provided to periodically back flush each filter unit without shutting off the whole system.

Energy metabolism in mobile, wild-sampled sharks inferred by plasma lipids.

Science.gov (United States)

Gallagher, Austin J; Skubel, Rachel A; Pethybridge, Heidi R; Hammerschlag, Neil

2017-01-01

Evaluating how predators metabolize energy is increasingly useful for conservation physiology, as it can provide information on their current nutritional condition. However, obtaining metabolic information from mobile marine predators is inherently challenging owing to their relative rarity, cryptic nature and often wide-ranging underwater movements. Here, we investigate aspects of energy metabolism in four free-ranging shark species ( n  = 281; blacktip, bull, nurse, and tiger) by measuring three metabolic parameters [plasma triglycerides (TAG), free fatty acids (FFA) and cholesterol (CHOL)] via non-lethal biopsy sampling. Plasma TAG, FFA and total CHOL concentrations (in millimoles per litre) varied inter-specifically and with season, year, and shark length varied within a species. The TAG were highest in the plasma of less active species (nurse and tiger sharks), whereas FFA were highest among species with relatively high energetic demands (blacktip and bull sharks), and CHOL concentrations were highest in bull sharks. Although temporal patterns in all metabolites were varied among species, there appeared to be peaks in the spring and summer, with ratios of TAG/CHOL (a proxy for condition) in all species displaying a notable peak in summer. These results provide baseline information of energy metabolism in large sharks and are an important step in understanding how the metabolic parameters can be assessed through non-lethal sampling in the future. In particular, this study emphasizes the importance of accounting for intra-specific and temporal variability in sampling designs seeking to monitor the nutritional condition and metabolic responses of shark populations.

Plasma functionalization of powdery nanomaterials using porous filter electrode and sample circulation

Science.gov (United States)

Lee, Deuk Yeon; Choi, Jae Hong; Shin, Jung Chul; Jung, Man Ki; Song, Seok Kyun; Suh, Jung Ki; Lee, Chang Young

2018-06-01

Compared with wet processes, dry functionalization using plasma is fast, scalable, solvent-free, and thus presents a promising approach for grafting functional groups to powdery nanomaterials. Previous approaches, however, had difficulties in maintaining an intimate sample-plasma contact and achieving uniform functionalization. Here, we demonstrate a plasma reactor equipped with a porous filter electrode that increases both homogeneity and degree of functionalization by capturing and circulating powdery carbon nanotubes (CNTs) via vacuum and gas blowing. Spectroscopic measurements verify that treatment with O2/air plasma generates oxygen-containing groups on the surface of CNTs, with the degree of functionalization readily controlled by varying the circulation number. Gas sensors fabricated using the plasma-treated CNTs confirm alteration of molecular adsorption on the surface of CNTs. A sequential treatment with NH3 plasma following the oxidation pre-treatment results in the functionalization with nitrogen species of up to 3.2 wt%. Our approach requiring no organic solvents not only is cost-effective and environmentally friendly, but also serves as a versatile tool that applies to other powdery micro or nanoscale materials for controlled modification of their surfaces.

Field desorption and field ion surface studies of samples exposed to the plasmas of PLT and ISX

International Nuclear Information System (INIS)

Kellogg, G.L.; Panitz, J.A.

1978-01-01

Modifications to the surface of field-ion specimens exposed to plasma discharges in PLT and ISX determined by Imaging Probe, Field Ion Microscope, and Transmission Electron Microscope analysis have in the past shown several consistent features. Surface films consisting primarily of limiter material with trapped plasma and impurity species have been found to reside on samples with direct line of sight exposure to the plasma during the discharges. Control specimens placed in the tokamak, but shielded from the plasma, on the other hand, remained free of deposits. When exposed to only high power plasma discharges, samples placed at the wall position in PLT and ISX have survived the exposures with no evidence of damage or implantation. In this paper we describe the results of a recent exposure in PLT in which for the first time samples of stainless steel were included for High-Field Surface Analysis. Tokamak operating conditions, including stainless-steel limiters, titanium gettering between discharges, and the occurrence of a disruption, also distinguished this exposure from those carried out previously. Surprisingly, even with stainless-steel limiters, carbon films were found to be deposited on the samples at a rate

Collection and control of tritium bioassay samples at Pantex

International Nuclear Information System (INIS)

Fairrow, N.L.; Ivie, W.E.

1992-01-01

Pantex is the final assembly/disassembly point for US nuclear weapons. The Pantex internal dosimetry section monitors radiation workers once a month for tritium exposure. In order to manage collection and control of the bioassay specimens efficiently, a bar code system for collection of samples was developed and implemented to speed up the process and decrease the number of errors probable when transferring data. In the past, all the bioassay data from samples were entered manually into a computer database. Transferring the bioassay data from the liquid scintillation counter to each individual's dosimetry record required as much as two weeks of concentrated effort

Collective effects in spin polarized plasmas

International Nuclear Information System (INIS)

Coppi, B.; Cowley, S.; Detragiache, P.; Kulsrud, R.; Pegoraro, F.

1984-10-01

A fusing plasma with coherently polarized spin nuclei can be subject to instabilities due to the anisotropy of the reaction product distributions in velocity space, which is a result of their polarization. The characteristics of these instabilities depend strongly on the plasma spatial inhomogeneities and a significant rate of spin depolarization can be produced by them if adequate fluctuation amplitudes are reached. The results of the relevant analysis are, in addition, of interest for plasma heating processes with frequencies in the range of the cyclotron frequencies of the considered nuclei

Fast egg collection method greatly improves randomness of egg sampling in Drosophila melanogaster

DEFF Research Database (Denmark)

Schou, Mads Fristrup

2013-01-01

When obtaining samples for population genetic studies, it is essential that the sampling is random. For Drosophila, one of the crucial steps in sampling experimental flies is the collection of eggs. Here an egg collection method is presented, which randomizes the eggs in a water column...... and diminishes environmental variance. This method was compared with a traditional egg collection method where eggs are collected directly from the medium. Within each method the observed and expected standard deviations of egg-to-adult viability were compared, whereby the difference in the randomness...... and to obtain a representative collection of genotypes, the method presented here is strongly recommended when collecting eggs from Drosophila....

Collective phenomena with energetic particles in fusion plasmas

International Nuclear Information System (INIS)

Breizman, B.N.; Berk, H.L.; Candy, J.

2001-01-01

Recent progress in the theory of collective modes driven by energetic particles, as well as interpretations of fast particle effects observed in fusion-related experiments, are described. New developments in linear theory include: (a) Alfven-mode frequency gap widening due to energetic trapped ions, (b) interpretation of JET results for plasma pressure effect on TAE modes, and (c) ''counter'' propagation of TAE modes due to trapped fast ion anisotropy. The new nonlinear results are: (a) theoretical explanation for the pitchfork splitting effect observed in TAE experiments on JET, (b) existence of coherent structures with strong frequency chirping due to kinetic instability, (c) self-consistent nonlinear theory for fishbone instabilities, and (d) intermittent quasilinear diffusion model for anomalous fast particle losses. (author)

Collective phenomena with energetic particles in fusion plasmas

International Nuclear Information System (INIS)

Breizman, B.N.; Berk, H.L.; Candy, J.

1999-01-01

Recent progress in the theory of collective modes driven by energetic particles, as well as interpretations of fast particle effects observed in fusion-related experiments, are described. New developments in linear theory include: (a) Alfven-mode frequency gap widening due to energetic trapped ions, (b) interpretation of JET results for plasma pressure effect on TAE modes, and (c) 'counter' propagation of TAE modes due to trapped fast ion anisotropy. The new nonlinear results are: (a) theoretical explanation for the pitchfork splitting effect observed in TAE experiments on JET, (b) existence of coherent structures with strong frequency chirping due to kinetic instability, (c) self-consistent nonlinear theory for fishbone instabilities, and (d) intermittent quasilinear diffusion model for anomalous fast particle losses. (author)

OSIRIS-REx Touch-and-Go (TAG) Mission Design for Asteroid Sample Collection

Science.gov (United States)

May, Alexander; Sutter, Brian; Linn, Timothy; Bierhaus, Beau; Berry, Kevin; Mink, Ron

2014-01-01

The Origins Spectral Interpretation Resource Identification Security Regolith Explorer (OSIRIS-REx) mission is a NASA New Frontiers mission launching in September 2016 to rendezvous with the near-Earth asteroid Bennu in October 2018. After several months of proximity operations to characterize the asteroid, OSIRIS-REx flies a Touch-And-Go (TAG) trajectory to the asteroid's surface to collect at least 60 g of pristine regolith sample for Earth return. This paper provides mission and flight system overviews, with more details on the TAG mission design and key events that occur to safely and successfully collect the sample. An overview of the navigation performed relative to a chosen sample site, along with the maneuvers to reach the desired site is described. Safety monitoring during descent is performed with onboard sensors providing an option to abort, troubleshoot, and try again if necessary. Sample collection occurs using a collection device at the end of an articulating robotic arm during a brief five second contact period, while a constant force spring mechanism in the arm assists to rebound the spacecraft away from the surface. Finally, the sample is measured quantitatively utilizing the law of conservation of angular momentum, along with qualitative data from imagery of the sampling device. Upon sample mass verification, the arm places the sample into the Stardust-heritage Sample Return Capsule (SRC) for return to Earth in September 2023.

Automated processing of whole blood samples into microliter aliquots of plasma.

Science.gov (United States)

Burtis, C A; Johnson, W W; Walker, W A

1988-01-01

A rotor that accepts and automatically processes a bulk aliquot of a single blood sample into multiple aliquots of plasma has been designed and built. The rotor consists of a central processing unit, which includes a disk containing eight precision-bore capillaries. By varying the internal diameters of the capillaries, aliquot volumes ranging 1 to 10 mul can be prepared. In practice, an unmeasured volume of blood is placed in a centre well, and, as the rotor begins to spin, is moved radially into a central annular ring where it is distributed into a series of processing chambers. The rotor is then spun at 3000 rpm for 10 min. When the centrifugal field is removed by slowly decreasing the rotor speed, an aliquot of plasma is withdrawn by capillary action into each of the capillary tubes. The disk containing the eight measured aliquots of plasma is subsequently removed and placed in a modifed rotor for conventional centrifugal analysis. Initial evaluation of the new rotor indicates that it is capable of producing discrete, microliter volumes of plasma with a degree of accuracy and precision approaching that of mechanical pipettes.

Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

International Nuclear Information System (INIS)

Rapp, Juergen; Aaron, A. M.; Bell, Gary L.; Burgess, Thomas W.; Ellis, Ronald James; Giuliano, D.; Howard, R.; Kiggans, James O.; Lessard, Timothy L.; Ohriner, Evan Keith; Perkins, Dale E.; Varma, Venugopal Koikal

2015-01-01

5-20 MW/m"2 and ion fluxes up to 10"2"4 m"-"2s"-"1. Since PFCs will have to withstand neutron irradiation displacement damage up to 50 dpa, the target station design must accommodate radioactive specimens (materials to be irradiated in HFIR or at SNS) to enable investigations of the impact of neutron damage on materials. Therefore, the system will have to be able to install and extract irradiated specimens using equipment and methods to avoid sample modification, control contamination, and minimize worker dose. Included in the design considerations will be an assessment of all the steps between neutron irradiation and post-exposure materials examination/characterization, as well as an evaluation of the facility hazard categorization. In particular, the factors associated with the acquisition of radioactive specimens and their preparation, transportation, experimental configuration at the plasma-specimen interface, post-plasma-exposure sample handling, and specimen preparation will be evaluated. Neutronics calculations to determine the dose rates of the samples were carried out for a large number of potential plasma-facing materials.

The UK Biobank sample handling and storage protocol for the collection, processing and archiving of human blood and urine.

Science.gov (United States)

Elliott, Paul; Peakman, Tim C

2008-04-01

UK Biobank is a large prospective study in the UK to investigate the role of genetic factors, environmental exposures and lifestyle in the causes of major diseases of late and middle age. Extensive data and biological samples are being collected from 500,000 participants aged between 40 and 69 years. The biological samples that are collected and how they are processed and stored will have a major impact on the future scientific usefulness of the UK Biobank resource. The aim of the UK Biobank sample handling and storage protocol is to specify methods for the collection and storage of participant samples that give maximum scientific return within the available budget. Processing or storage methods that, as far as can be predicted, will preclude current or future assays have been avoided. The protocol was developed through a review of the literature on sample handling and processing, wide consultation within the academic community and peer review. Protocol development addressed which samples should be collected, how and when they should be processed and how the processed samples should be stored to ensure their long-term integrity. The recommended protocol was extensively tested in a series of validation studies. UK Biobank collects about 45 ml blood and 9 ml of urine with minimal local processing from each participant using the vacutainer system. A variety of preservatives, anti-coagulants and clot accelerators is used appropriate to the expected end use of the samples. Collection of other material (hair, nails, saliva and faeces) was also considered but rejected for the full cohort. Blood and urine samples from participants are transported overnight by commercial courier to a central laboratory where they are processed and aliquots of urine, plasma, serum, white cells and red cells stored in ultra-low temperature archives. Aliquots of whole blood are also stored for potential future production of immortalized cell lines. A standard panel of haematology assays is

Speciation of arsenic in biological samples.

Science.gov (United States)

Mandal, Badal Kumar; Ogra, Yasumitsu; Anzai, Kazunori; Suzuki, Kazuo T

2004-08-01

Speciation of arsenicals in biological samples is an essential tool to gain insight into its distribution in tissues and its species-specific toxicity to target organs. Biological samples (urine, hair, fingernail) examined in the present study were collected from 41 people of West Bengal, India, who were drinking arsenic (As)-contaminated water, whereas 25 blood and urine samples were collected from a population who stopped drinking As contaminated water 2 years before the blood collection. Speciation of arsenicals in urine, water-methanol extract of freeze-dried red blood cells (RBCs), trichloroacetic acid treated plasma, and water extract of hair and fingernail was carried out by high-performance liquid chromatography (HPLC)-inductively coupled argon plasma mass spectrometry (ICP MS). Urine contained arsenobetaine (AsB, 1.0%), arsenite (iAs(III), 11.3), arsenate (iAs(V), 10.1), monomethylarsonous acid (MMA(III), 6.6), monomethylarsonic acid (MMA(V), 10.5), dimethylarsinous acid (DMA(III), 13.0), and dimethylarsinic acid (DMA(V), 47.5); fingernail contained iAs(III) (62.4%), iAs(V) (20.2), MMA(V) (5.7), DMA(III) (8.9), and DMA(V) (2.8); hair contained iAs(III) (58.9%), iAs(V) (34.8), MMA(V) (2.9), and DMA(V) (3.4); RBCs contained AsB (22.5%) and DMA(V) (77.5); and blood plasma contained AsB (16.7%), iAs(III) (21.1), MMA(V) (27.1), and DMA(V) (35.1). MMA(III), DMA(III), and iAs(V) were not found in any plasma and RBCs samples, but urine contained all of them. Arsenic in urine, fingernails, and hair are positively correlated with water As, suggesting that any of these measurements could be considered as a biomarker to As exposure. Status of urine and exogenous contamination of hair urgently need speciation of As in these samples, but speciation of As in nail is related to its total As (tAs) concentration. Therefore, total As concentrations of nails could be considered as biomarker to As exposure in the endemic areas.

Speciation of arsenic in biological samples

International Nuclear Information System (INIS)

Mandal, Badal Kumar; Ogra, Yasumitsu; Anzai, Kazunori; Suzuki, Kazuo T.

2004-01-01

Speciation of arsenicals in biological samples is an essential tool to gain insight into its distribution in tissues and its species-specific toxicity to target organs. Biological samples (urine, hair, fingernail) examined in the present study were collected from 41 people of West Bengal, India, who were drinking arsenic (As)-contaminated water, whereas 25 blood and urine samples were collected from a population who stopped drinking As contaminated water 2 years before the blood collection. Speciation of arsenicals in urine, water-methanol extract of freeze-dried red blood cells (RBCs), trichloroacetic acid treated plasma, and water extract of hair and fingernail was carried out by high-performance liquid chromatography (HPLC)-inductively coupled argon plasma mass spectrometry (ICP MS). Urine contained arsenobetaine (AsB, 1.0%), arsenite (iAs III , 11.3), arsenate (iAs V , 10.1), monomethylarsonous acid (MMA III , 6.6), monomethylarsonic acid (MMA V , 10.5), dimethylarsinous acid (DMA III , 13.0), and dimethylarsinic acid (DMA V , 47.5); fingernail contained iAs III (62.4%), iAs V (20.2), MMA V (5.7), DMA III (8.9), and DMA V (2.8); hair contained iAs III (58.9%), iAs V (34.8), MMA V (2.9), and DMA V (3.4); RBCs contained AsB (22.5%) and DMA V (77.5); and blood plasma contained AsB (16.7%), iAs III (21.1), MMA V (27.1), and DMA V (35.1). MMA III , DMA III , and iAs V were not found in any plasma and RBCs samples, but urine contained all of them. Arsenic in urine, fingernails, and hair are positively correlated with water As, suggesting that any of these measurements could be considered as a biomarker to As exposure. Status of urine and exogenous contamination of hair urgently need speciation of As in these samples, but speciation of As in nail is related to its total As (tAs) concentration. Therefore, total As concentrations of nails could be considered as biomarker to As exposure in the endemic areas

A 'feather-trap' for collecting DNA samples from birds.

Science.gov (United States)

Maurer, Golo; Beck, Nadeena; Double, Michael C

2010-01-01

Genetic analyses of birds are usually based on DNA extracted from a blood sample. For some species, however, obtaining blood samples is difficult because they are sensitive to handling, pose a conservation or animal welfare concern, or evade capture. In such cases, feathers obtained from live birds in the wild can provide an alternative source of DNA. Here, we provide the first description and evaluation of a 'feather-trap', consisting of small strips of double-sided adhesive tape placed close to a nest with chicks, as a simple, inexpensive and minimally invasive method to collect feathers. The feather-trap was tested in tropical conditions on the Australian pheasant coucal (Centropus phasianinus). None of the 12 pairs of coucals on which the feather-trap was used abandoned the nest, and feeding rates did not differ from those of birds not exposed to a feather-trap. On average, 4.2 feathers were collected per trap over 2-5 days and, despite exposure to monsoonal rain, DNA was extracted from 71.4% of samples, albeit at low concentrations. The amount of genomic DNA extracted from each feather was sufficient to reliably genotype individuals at up to five microsatellite loci for parentage analysis. We show that a feather-trap can provide a reliable alternative for obtaining DNA in species where taking blood is difficult. It may also prove useful for collecting feather samples for other purposes, e.g. stable-isotope analysis. © 2009 Blackwell Publishing Ltd.

Determination of uranium from nuclear fuel in environmental samples using inductively coupled plasma mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Boulyga, S.F. [Forschungszentrum Juelich GmbH (Germany). Zentralabteilung fuer Chemische Analysen]|[Radiation Physics and Chemistry Problems Inst., Minsk (Belarus); Becker, J.S. [Forschungszentrum Juelich GmbH (Germany). Zentralabteilung fuer Chemische Analysen

2000-11-01

As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The {sup 236}U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on inductively coupled plasma quadrupole mass spectrometry with a hexapole collision cell (HEX-ICP-QMS). The figures of merit of the HEX-ICP-QMS were studied with a plasma-shielded torch using different nebulizers (such as an ultrasonic nebulizer (USN) and Meinhard nebulizer) for solution introduction. A {sup 238}U{sup +} ion intensity of up to 27000 MHz/ppm in HEX-ICP-QMS with USN was observed by introducing helium into the hexapole collision cell as the collision gas at a flow rate of 10 ml min{sup -1}. The formation rate of uranium hydride ions UH{sup +}/U{sup +} of 2 x 10{sup -6} was obtained by using USN with a membrane desolvator. The limit of {sup 236}U/{sup 238}U ratio determination in 10 {mu}g 1{sup -1} uranium solution was 3 x 10{sup -7} corresponding to the detection limit for {sup 236}U of 3 pg 1{sup -1}. The precision of uranium isotopic ratio measurements in 10 {mu}g 1{sup -1} laboratory uranium isotopic standard solution was 0.13% ({sup 235}U/{sup 238}U) and 0.33% ({sup 236}U/{sup 238}U) using a Meinhard nebulizer and 0.45% ({sup 235}U/{sup 238}U) and 0.88% ({sup 236}U/{sup 238}U) using a USN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the {sup 236}U/{sup 238}U ratio ranged from 10{sup -5} to 10{sup -3}. (orig.)

New high temperature plasmas and sample introduction systems for analytical atomic emission and mass spectrometry

International Nuclear Information System (INIS)

Montaser, A.

1993-01-01

In this research, new high-temperature plasmas and new sample introduction systems are explored for rapid elemental and isotopic analysis of gases, solutions, and solids using mass spectrometry and atomic emission spectrometry. During the period January 1993--December 1993, emphasis was placed on (a) analytical investigations of atmospheric-pressure helium inductively coupled plasma (He ICP) that are suitable for atomization, excitation, and ionization of elements possessing high excitation and ionization energies; (b) simulation and computer modeling of plasma sources to predict their structure and fundamental and analytical properties without incurring the enormous cost of experimental studies; (c) spectrosopic imaging and diagnostic studies of high-temperature plasmas; (d) fundamental studies of He ICP discharges and argon-nitrogen plasma by high-resolution Fourier transform spectrometry; and (e) fundamental and analytical investigation of new, low-cost devices as sample introduction systems for atomic spectrometry and examination of new diagnostic techniques for probing aerosols. Only the most important achievements are included in this report to illustrate progress and obstacles. Detailed descriptions of the authors' investigations are outlined in the reprints and preprints that accompany this report. The technical progress expected next year is briefly described at the end of this report

Liquid sampling-atmospheric pressure glow discharge as a secondary excitation source: Assessment of plasma characteristics

Science.gov (United States)

Manard, Benjamin T.; Gonzalez, Jhanis J.; Sarkar, Arnab; Dong, Meirong; Chirinos, Jose; Mao, Xianglei; Russo, Richard E.; Marcus, R. Kenneth

The liquid sampling-atmospheric pressure glow discharge (LS-APGD) has been assessed as a secondary excitation source with a parametric evaluation regarding carrier gas flow rate, applied current, and electrode distance. With this parametric evaluation, plasma optical emission was monitored in order to obtain a fundamental understanding with regards to rotational temperature (Trot), excitation temperature (Texc), electron number density (ne), and plasma robustness. Incentive for these studies is not only for a greater overall fundamental knowledge of the APGD, but also in instrumenting a secondary excitation/ionization source following laser ablation (LA). Rotational temperatures were determined through experimentally fitting of the N2 and OH molecular emission bands while atomic excitation temperatures were calculated using a Boltzmann distribution of He and Mg atomic lines. The rotational and excitation temperatures were determined to be ~ 1000 K and ~ 2700 K respectively. Electron number density was calculated to be on the order of ~ 3 × 1015 cm- 3 utilizing Stark broadening effects of the Hα line of the Balmer series and a He I transition. In addition, those diagnostics were performed introducing magnesium (by solution feed and laser ablation) into the plasma in order to determine any perturbation under heavy matrix sampling. The so-called plasma robustness factor, derived by monitoring Mg II/Mg I emission ratios, is also employed as a reflection of potential perturbations in microplasma energetics across the various operation conditions and sample loadings. While truly a miniaturized source (laser ablation sample introduction.

Evaluation of some pollutant levels in environmental samples collected from the area of the new campus of Taif University.

Science.gov (United States)

Sharshar, Taher; Hassan, H Ebrahim; Arida, Hassan A; Aydarous, Abdulkadir; Bazaid, Salih A; Ahmed, Mamdouh A

2013-01-01

The levels of radioactivity and heavy metals in soil, plant and groundwater samples collected from the area of the new campus of Taif University, Saudi Arabia, and its neighbouring areas have been determined. High-resolution gamma-ray spectroscopy was used for radioactivity measurements, and inductively coupled plasma atomic emission spectroscopy was used to determine the concentration of heavy metals. The means of (226)Ra, (228)Ra and (40)K concentrations in water samples collected from four wells were found to be 0.13 ± 0.03, 0.05 ± 0.03 and 1.3 ± 0.5 Bq l(-1), respectively. The means of (238)U, (226)Ra, (228)Ra ((232)Th for soil samples) and (40)K concentrations in wild plant and soil samples were found to be 3.7 ± 4.1, 8.8 ± 11.6, 3.8 ± 2.9 and 1025 ± 685, and 8.6 ± 3.4, 12.8 ± 3.4, 16.6 ± 7.1 and 618 ± 82 Bq kg(-1) dry weight (DW), respectively. The (137)Cs of artificial origin was also detected in soil samples with a mean concentration of 3.8 ± 2.2 Bq kg(-1) DW. Evaluating the results, it can be concluded that the concentrations of (238)U, (226)Ra, (232)Th and (40)K in soil samples fall within the world average. Furthermore, 19 trace and major elements in groundwater samples and 22 elements in soil and plant samples were determined. The sampling locations of soil can be classified into three groups (relatively high, medium and low polluted) according to their calculated metal pollution index using the contents of trace and major elements. A cluster analysis of the contents of radioactivity and trace element contents in soil samples shows the presence of two main distinct clusters of sampling locations.

Heparin removal by ecteola-cellulose pre-treatment enables the use of plasma samples for accurate measurement of anti-Yellow fever virus neutralizing antibodies.

Science.gov (United States)

Campi-Azevedo, Ana Carolina; Peruhype-Magalhães, Vanessa; Coelho-Dos-Reis, Jordana Grazziela; Costa-Pereira, Christiane; Yamamura, Anna Yoshida; Lima, Sheila Maria Barbosa de; Simões, Marisol; Campos, Fernanda Magalhães Freire; de Castro Zacche Tonini, Aline; Lemos, Elenice Moreira; Brum, Ricardo Cristiano; de Noronha, Tatiana Guimarães; Freire, Marcos Silva; Maia, Maria de Lourdes Sousa; Camacho, Luiz Antônio Bastos; Rios, Maria; Chancey, Caren; Romano, Alessandro; Domingues, Carla Magda; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis

2017-09-01

Technological innovations in vaccinology have recently contributed to bring about novel insights for the vaccine-induced immune response. While the current protocols that use peripheral blood samples may provide abundant data, a range of distinct components of whole blood samples are required and the different anticoagulant systems employed may impair some properties of the biological sample and interfere with functional assays. Although the interference of heparin in functional assays for viral neutralizing antibodies such as the functional plaque-reduction neutralization test (PRNT), considered the gold-standard method to assess and monitor the protective immunity induced by the Yellow fever virus (YFV) vaccine, has been well characterized, the development of pre-analytical treatments is still required for the establishment of optimized protocols. The present study intended to optimize and evaluate the performance of pre-analytical treatment of heparin-collected blood samples with ecteola-cellulose (ECT) to provide accurate measurement of anti-YFV neutralizing antibodies, by PRNT. The study was designed in three steps, including: I. Problem statement; II. Pre-analytical steps; III. Analytical steps. Data confirmed the interference of heparin on PRNT reactivity in a dose-responsive fashion. Distinct sets of conditions for ECT pre-treatment were tested to optimize the heparin removal. The optimized protocol was pre-validated to determine the effectiveness of heparin plasma:ECT treatment to restore the PRNT titers as compared to serum samples. The validation and comparative performance was carried out by using a large range of serum vs heparin plasma:ECT 1:2 paired samples obtained from unvaccinated and 17DD-YFV primary vaccinated subjects. Altogether, the findings support the use of heparin plasma:ECT samples for accurate measurement of anti-YFV neutralizing antibodies. Copyright © 2017 Elsevier B.V. All rights reserved.

A liquid chromatography/tandem mass spectrometry assay for the analysis of atomoxetine in human plasma and in vitro cellular samples

Science.gov (United States)

Appel, David I.; Brinda, Bryan; Markowitz, John S.; Newcorn, Jeffrey H.; Zhu, Hao-Jie

2012-01-01

A simple, rapid and sensitive method for quantification of atomoxetine by liquid chromatography- tandem mass spectrometry (LC-MS/MS) was developed. This assay represents the first LC-MS/MS quantification method for atomoxetine utilizing electrospray ionization. Deuterated atomoxetine (d3-atomoxetine) was adopted as the internal standard. Direct protein precipitation was utilized for sample preparation. This method was validated for both human plasma and in vitro cellular samples. The lower limit of quantification was 3 ng/ml and 10 nM for human plasma and cellular samples, respectively. The calibration curves were linear within the ranges of 3 ng/ml to 900 ng/ml and 10 nM to 10 μM for human plasma and cellular samples, respectively (r2 > 0.999). The intra- and inter-day assay accuracy and precision were evaluated using quality control samples at 3 different concentrations in both human plasma and cellular lysate. Sample run stability, assay selectivity, matrix effect, and recovery were also successfully demonstrated. The present assay is superior to previously published LC-MS and LC-MS/MS methods in terms of sensitivity or the simplicity of sample preparation. This assay is applicable to the analysis of atomoxetine in both human plasma and in vitro cellular samples. PMID:22275222

Ground-water sample collection and analysis plan for the ground-water surveillance project

International Nuclear Information System (INIS)

Bryce, R.W.; Evans, J.C.; Olsen, K.B.

1991-12-01

The Pacific Northwest Laboratory performs ground-water sampling activities at the US Department of Energy's (DOE's) Hanford Site in support of DOE's environmental surveillance responsibilities. The purpose of this document is to translate DOE's General Environmental Protection Program (DOE Order 5400.1) into a comprehensive ground-water sample collection and analysis plan for the Hanford Site. This sample collection and analysis plan sets forth the environmental surveillance objectives applicable to ground water, identifies the strategy for selecting sample collection locations, and lists the analyses to be performed to meet those objectives

Biopolymers for Sample Collection, Protection, and Preservation

Science.gov (United States)

2015-05-19

knowledge of sample collection from various matrices is crucial. Recovery and preservation of microorganisms prior to analysis are important...Another method for encapsulating bacteria for use in biodegradation of gasoline involves a complex process using gellan gum (Moslemy et al. 2002). Many...use of acacia gum in preserving microorganisms for extended periods of time without refrigeration (Krumnow et al. 2009; Sorokulova et al. 2008, 2012

Remote blood collection in reindeer (Rangifer tarandus tarandus L: a preliminary study

Directory of Open Access Journals (Sweden)

E. Wiklund

1994-12-01

Full Text Available Automatic blood sampling equipment (ABSE was used successfully to collect blood samples from two reindeer. During blood sampling, two methods of restraint were applied which caused no short term changes in plasma concentrations of urea, aspartate aminotransferase, alanine aminotransferase or total protein. Plasma Cortisol concentrations were significantly elevated by the two restraint techniques. The value of ABSE in studies of stress in reindeer is discussed.

A very sensitive ion collection device for plasma-laser characterization.

Science.gov (United States)

Cavallaro, S; Torrisi, L; Cutroneo, M; Amato, A; Sarta, F; Wen, L

2012-06-01

In this paper a very sensitive ion collection device, for diagnostic of laser ablated-target plasma, is described. It allows for reducing down to few microvolts the signal threshold at digital scope input. A standard ion collector is coupled to a transimpedance amplifier, specially designed, which increases data acquisition sensitivity by a gain ≈1100 and does not introduce any significant distortion of input signal. By time integration of current intensity, an amount of charge as small as 2.7 × 10(-2) pC can be detected for photopeak events.

Liquid sampling-atmospheric pressure glow discharge as a secondary excitation source: Assessment of plasma characteristics

International Nuclear Information System (INIS)

Manard, Benjamin T.; Gonzalez, Jhanis J.; Sarkar, Arnab; Dong, Meirong; Chirinos, Jose; Mao, Xianglei; Russo, Richard E.; Marcus, R. Kenneth

2014-01-01

The liquid sampling-atmospheric pressure glow discharge (LS-APGD) has been assessed as a secondary excitation source with a parametric evaluation regarding carrier gas flow rate, applied current, and electrode distance. With this parametric evaluation, plasma optical emission was monitored in order to obtain a fundamental understanding with regards to rotational temperature (T rot ), excitation temperature (T exc ), electron number density (n e ), and plasma robustness. Incentive for these studies is not only for a greater overall fundamental knowledge of the APGD, but also in instrumenting a secondary excitation/ionization source following laser ablation (LA). Rotational temperatures were determined through experimentally fitting of the N 2 and OH molecular emission bands while atomic excitation temperatures were calculated using a Boltzmann distribution of He and Mg atomic lines. The rotational and excitation temperatures were determined to be ∼ 1000 K and ∼ 2700 K respectively. Electron number density was calculated to be on the order of ∼ 3 × 10 15 cm −3 utilizing Stark broadening effects of the Hα line of the Balmer series and a He I transition. In addition, those diagnostics were performed introducing magnesium (by solution feed and laser ablation) into the plasma in order to determine any perturbation under heavy matrix sampling. The so-called plasma robustness factor, derived by monitoring Mg II/Mg I emission ratios, is also employed as a reflection of potential perturbations in microplasma energetics across the various operation conditions and sample loadings. While truly a miniaturized source ( 3 volume), the LS-APGD is shown to be quite robust with plasma characteristics and temperatures being unaffected upon introduction of metal species, whether by liquid or laser ablation sample introduction. - Highlights: • Liquid sampling-atmospheric pressure glow discharge (LS-APGD) • LS-APGD as a secondary excitation source for laser-ablated (LA

Is it acceptable to use coagulation plasma samples stored at room temperature and 4°C for 24 hours for additional prothrombin time, activated partial thromboplastin time, fibrinogen, antithrombin, and D-dimer testing?

Science.gov (United States)

Rimac, V; Coen Herak, D

2017-10-01

Coagulation laboratories are faced on daily basis with requests for additional testing in already analyzed fresh plasma samples. This prompted us to examine whether plasma samples stored at room temperature (RT), and 4°C for 24 hours can be accepted for additional prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen (Fbg), antithrombin (AT), and D-dimer testing. We measured PT, aPTT, Fbg in 50 and AT in 30 plasma samples with normal and pathological values, within 4 hours of blood collection (baseline results) and after 24-hours storage at RT (primary tubes), and 4°C (aliquots). D-dimer stability was investigated in 20 samples stored in primary tubes at 4°C. No statistically significant difference between baseline results and results in samples stored at RT and 4°C was observed for PT (P=.938), aPTT (P=.186), Fbg (P=.962), AT (P=.713), and D-dimers (P=.169). The highest median percentage changes were found for aPTT, being more pronounced for samples stored at 4°C (13.0%) than at RT (8.7%). Plasma samples stored both at RT and 4°C for 24 hours are acceptable for additional PT, Fbg, and AT testing. Plasma samples stored 24 hours in primary tubes at 4°C are suitable for D-dimer testing. © 2017 John Wiley & Sons Ltd.

Importance of sampling frequency when collecting diatoms

KAUST Repository

Wu, Naicheng

2016-11-14

There has been increasing interest in diatom-based bio-assessment but we still lack a comprehensive understanding of how to capture diatoms’ temporal dynamics with an appropriate sampling frequency (ASF). To cover this research gap, we collected and analyzed daily riverine diatom samples over a 1-year period (25 April 2013–30 April 2014) at the outlet of a German lowland river. The samples were classified into five clusters (1–5) by a Kohonen Self-Organizing Map (SOM) method based on similarity between species compositions over time. ASFs were determined to be 25 days at Cluster 2 (June-July 2013) and 13 days at Cluster 5 (February-April 2014), whereas no specific ASFs were found at Cluster 1 (April-May 2013), 3 (August-November 2013) (>30 days) and Cluster 4 (December 2013 - January 2014) (<1 day). ASFs showed dramatic seasonality and were negatively related to hydrological wetness conditions, suggesting that sampling interval should be reduced with increasing catchment wetness. A key implication of our findings for freshwater management is that long-term bio-monitoring protocols should be developed with the knowledge of tracking algal temporal dynamics with an appropriate sampling frequency.

Comparison of ESR1 Mutations in Tumor Tissue and Matched Plasma Samples from Metastatic Breast Cancer Patients

Directory of Open Access Journals (Sweden)

Takashi Takeshita

2017-10-01

Full Text Available BACKGROUND: ESR1 mutation in circulating cell-free DNA (cfDNA is emerging as a noninvasive biomarker of acquired resistance to endocrine therapy, but there is a paucity of data comparing the status of ESR1 gene in cfDNA with that in its corresponding tumor tissue. The objective of this study is to validate the degree of concordance of ESR1 mutations between plasma and tumor tissue. METHODS: ESR1 ligand-binding domain mutations Y537S, Y537N, Y537C, and D538G were analyzed using droplet digital PCR in 35 patients with metastatic breast cancer (MBC (35 tumor tissue samples and 67 plasma samples. RESULTS: Of the 35 paired samples, 26 (74.3% were concordant: one patient had detectable ESR1 mutations both plasma (ESR1 Y537S/Y537N and tumor tissue (ESR1 Y537S/Y537C, and 25 had WT ESR1 alleles in both. Nine (25.7% had discordance between the plasma and tissue results: five had mutations detected only in their tumor tissue (two Y537S, one Y537C, one D538G, and one Y537S/Y537N/D538G, and four had mutations detected only in their plasma (one Y537S, one Y537N, and two Y537S/Y537N/D538G. Furthermore, longitudinal plasma samples from 19 patients were used to assess changes in the presence of ESR1 mutations during treatment. Eleven patients had cfDNA ESR1 mutations over the course of treatment. A total of eight of 11 patients with MBC with cfDNA ESR1 mutations (72.7% had the polyclonal mutations. CONCLUSION: We have shown the independent distribution of ESR1 mutations between plasma and tumor tissue in 35 patients with MBC.

Evaluation of a cost effective in-house method for HIV-1 drug resistance genotyping using plasma samples.

Directory of Open Access Journals (Sweden)

Devidas N Chaturbhuj

Full Text Available OBJECTIVES: Validation of a cost effective in-house method for HIV-1 drug resistance genotyping using plasma samples. DESIGN: The validation includes the establishment of analytical performance characteristics such as accuracy, reproducibility, precision and sensitivity. METHODS: The accuracy was assessed by comparing 26 paired Virological Quality Assessment (VQA proficiency testing panel sequences generated by in-house and ViroSeq Genotyping System 2.0 (Celera Diagnostics, US as a gold standard. The reproducibility and precision were carried out on five samples with five replicates representing multiple HIV-1 subtypes (A, B, C and resistance patterns. The amplification sensitivity was evaluated on HIV-1 positive plasma samples (n = 88 with known viral loads ranges from 1000-1.8 million RNA copies/ml. RESULTS: Comparison of the nucleotide sequences generated by ViroSeq and in-house method showed 99.41±0.46 and 99.68±0.35% mean nucleotide and amino acid identity respectively. Out of 135 Stanford HIVdb listed HIV-1 drug resistance mutations, partial discordance was observed at 15 positions and complete discordance was absent. The reproducibility and precision study showed high nucleotide sequence identities i.e. 99.88±0.10 and 99.82±0.20 respectively. The in-house method showed 100% analytical sensitivity on the samples with HIV-1 viral load >1000 RNA copies/ml. The cost of running the in-house method is only 50% of that for ViroSeq method (112$ vs 300$, thus making it cost effective. CONCLUSIONS: The validated cost effective in-house method may be used to collect surveillance data on the emergence and transmission of HIV-1 drug resistance in resource limited countries. Moreover, the wide applications of a cost effective and validated in-house method for HIV-1 drug resistance testing will facilitate the decision making for the appropriate management of HIV infected patients.

On the improvement of blood sample collection at clinical laboratories.

Science.gov (United States)

Grasas, Alex; Ramalhinho, Helena; Pessoa, Luciana S; Resende, Mauricio G C; Caballé, Imma; Barba, Nuria

2014-01-09

Blood samples are usually collected daily from different collection points, such hospitals and health centers, and transported to a core laboratory for testing. This paper presents a project to improve the collection routes of two of the largest clinical laboratories in Spain. These routes must be designed in a cost-efficient manner while satisfying two important constraints: (i) two-hour time windows between collection and delivery, and (ii) vehicle capacity. A heuristic method based on a genetic algorithm has been designed to solve the problem of blood sample collection. The user enters the following information for each collection point: postal address, average collecting time, and average demand (in thermal containers). After implementing the algorithm using C programming, this is run and, in few seconds, it obtains optimal (or near-optimal) collection routes that specify the collection sequence for each vehicle. Different scenarios using various types of vehicles have been considered. Unless new collection points are added or problem parameters are changed substantially, routes need to be designed only once. The two laboratories in this study previously planned routes manually for 43 and 74 collection points, respectively. These routes were covered by an external carrier company. With the implementation of this algorithm, the number of routes could be reduced from ten to seven in one laboratory and from twelve to nine in the other, which represents significant annual savings in transportation costs. The algorithm presented can be easily implemented in other laboratories that face this type of problem, and it is particularly interesting and useful as the number of collection points increases. The method designs blood collection routes with reduced costs that meet the time and capacity constraints of the problem.

Analysis of bioethanol samples through Inductively Coupled Plasma Mass Spectrometry with a total sample consumption system

Science.gov (United States)

Sánchez, Carlos; Lienemann, Charles-Philippe; Todolí, Jose-Luis

2016-10-01

Bioethanol real samples have been directly analyzed through ICP-MS by means of the so called High Temperature Torch Integrated Sample Introduction System (hTISIS). Because bioethanol samples may contain water, experiments have been carried out in order to determine the effect of ethanol concentration on the ICP-MS response. The ethanol content studied went from 0 to 50%, because higher alcohol concentrations led to carbon deposits on the ICP-MS interface. The spectrometer default spray chamber (double pass) equipped with a glass concentric pneumatic micronebulizer has been taken as the reference system. Two flow regimes have been evaluated: continuous sample aspiration at 25 μL min- 1 and 5 μL air-segmented sample injection. hTISIS temperature has been shown to be critical, in fact ICP-MS sensitivity increased with this variable up to 100-200 °C depending on the solution tested. Higher chamber temperatures led to either a drop in signal or a plateau. Compared with the reference system, the hTISIS improved the sensitivities by a factor included within the 4 to 8 range while average detection limits were 6 times lower for the latter device. Regarding the influence of the ethanol concentration on sensitivity, it has been observed that an increase in the temperature was not enough to eliminate the interferences. It was also necessary to modify the torch position with respect to the ICP-MS interface to overcome them. This fact was likely due to the different extent of ion plasma radial diffusion encountered as a function of the matrix when working at high chamber temperatures. When the torch was moved 1 mm plasma down axis, ethanolic and aqueous solutions provided statistically equal sensitivities. A preconcentration procedure has been applied in order to validate the methodology. It has been found that, under optimum conditions from the point of view of matrix effects, recoveries for spiked samples were close to 100%. Furthermore, analytical concentrations for real

Active Collection of Land Cover Sample Data from Geo-Tagged Web Texts

Directory of Open Access Journals (Sweden)

Dongyang Hou

2015-05-01

Full Text Available Sample data plays an important role in land cover (LC map validation. Traditionally, they are collected through field survey or image interpretation, either of which is costly, labor-intensive and time-consuming. In recent years, massive geo-tagged texts are emerging on the web and they contain valuable information for LC map validation. However, this kind of special textual data has seldom been analyzed and used for supporting LC map validation. This paper examines the potential of geo-tagged web texts as a new cost-free sample data source to assist LC map validation and proposes an active data collection approach. The proposed approach uses a customized deep web crawler to search for geo-tagged web texts based on land cover-related keywords and string-based rules matching. A data transformation based on buffer analysis is then performed to convert the collected web texts into LC sample data. Using three provinces and three municipalities directly under the Central Government in China as study areas, geo-tagged web texts were collected to validate artificial surface class of China’s 30-meter global land cover datasets (GlobeLand30-2010. A total of 6283 geo-tagged web texts were collected at a speed of 0.58 texts per second. The collected texts about built-up areas were transformed into sample data. User’s accuracy of 82.2% was achieved, which is close to that derived from formal expert validation. The preliminary results show that geo-tagged web texts are valuable ancillary data for LC map validation and the proposed approach can improve the efficiency of sample data collection.

Probing Leader Cells in Endothelial Collective Migration by Plasma Lithography Geometric Confinement

OpenAIRE

Yongliang Yang; Nima Jamilpour; Baoyin Yao; Zachary S. Dean; Reza Riahi; Pak Kin Wong

2016-01-01

When blood vessels are injured, leader cells emerge in the endothelium to heal the wound and restore the vasculature integrity. The characteristics of leader cells during endothelial collective migration under diverse physiological conditions, however, are poorly understood. Here we investigate the regulation and function of endothelial leader cells by plasma lithography geometric confinement generated. Endothelial leader cells display an aggressive phenotype, connect to follower cells via pe...

Collection and preparation of wet and dry stream-sediment samples

International Nuclear Information System (INIS)

Puchlik, K.

1977-03-01

Lawrence Livermore Laboratory is responsible for the Hydrogeochemistry and Stream Sediment Reconnaissance (HSSR) program for uranium in the seven far western states. The work thus far has concentrated on the arid to semi-arid regions of the West and this paper discusses the collection and preparation of sediment samples in the Basin and Range province. The sample collection and preparation procedures described here may not be applicable to other parts of the far western states or other areas. These procedures also differ somewhat from those used by the other three laboratories involved in the HSSR program

Treatment of carprofen overdose with therapeutic plasma exchange in a dog.

Science.gov (United States)

Kjaergaard, Astrid B; Davis, Jennifer L; Acierno, Mark J

2018-06-13

To report the use of therapeutic plasma exchange (TPE) in a dog with carprofen toxicosis. A 6-year-old female neutered Bichon Frise weighing 6.9 kg was examined after it had ingested 72 mg/kg carprofen. Mild dehydration without azotemia and with a urine specific gravity of 1.050 was noted at presentation. Treatment consisted of induction of emesis, symptomatic medical therapy, and TPE. The TPE achieved 1.5 plasma volume exchanges over 3 hours. Blood samples and effluent samples were collected every 30 minutes during TPE and additional blood samples were collected 11 and 35 hours after treatment. Carprofen concentrations in these samples were determined by high-pressure liquid chromatography. A 51% reduction in serum carprofen concentration was achieved following TPE. This report describes the successful reduction of plasma carprofen concentration in a dog using TPE. Although recent studies suggest that this particular dog may not have received a toxic dose, a 51% reduction of plasma carprofen concentration was achieved over 180 minutes, and TPE may be beneficial for treatment of dogs that have ingested higher doses. © Veterinary Emergency and Critical Care Society 2018.

Porous Silicon Antibody Microarrays for Quantitative Analysis: Measurement of Free and Total PSA in Clinical Plasma Samples

Science.gov (United States)

Tojo, Axel; Malm, Johan; Marko-Varga, György; Lilja, Hans; Laurell, Thomas

2014-01-01

The antibody microarrays have become widespread, but their use for quantitative analyses in clinical samples has not yet been established. We investigated an immunoassay based on nanoporous silicon antibody microarrays for quantification of total prostate-specific-antigen (PSA) in 80 clinical plasma samples, and provide quantitative data from a duplex microarray assay that simultaneously quantifies free and total PSA in plasma. To further develop the assay the porous silicon chips was placed into a standard 96-well microtiter plate for higher throughput analysis. The samples analyzed by this quantitative microarray were 80 plasma samples obtained from men undergoing clinical PSA testing (dynamic range: 0.14-44ng/ml, LOD: 0.14ng/ml). The second dataset, measuring free PSA (dynamic range: 0.40-74.9ng/ml, LOD: 0.47ng/ml) and total PSA (dynamic range: 0.87-295ng/ml, LOD: 0.76ng/ml), was also obtained from the clinical routine. The reference for the quantification was a commercially available assay, the ProStatus PSA Free/Total DELFIA. In an analysis of 80 plasma samples the microarray platform performs well across the range of total PSA levels. This assay might have the potential to substitute for the large-scale microtiter plate format in diagnostic applications. The duplex assay paves the way for a future quantitative multiplex assay, which analyses several prostate cancer biomarkers simultaneously. PMID:22921878

Plasma interaction with tungsten samples in the COMPASS tokamak in ohmic ELMy H-modes

International Nuclear Information System (INIS)

Dimitrova, M; Weinzettl, V; Matejicek, J; Dejarnac, R; Stöckel, J; Havlicek, J; Panek, R; Popov, Tsv; Marinov, S; Costea, S

2016-01-01

This paper reports experimental results on plasma interaction with tungsten samples with or without pre-grown He fuzz. Under the experimental conditions, arcing was observed on the fuzzy tungsten samples, resulting in localized melting of the fuzz structure that did not extend into the bulk. The parallel power flux densities were obtained from the data measured by Langmuir probes embedded in the divertor tiles on the COMPASS tokamak. Measurements of the current-voltage probe characteristics were performed during ohmic ELMy H-modes reached in deuterium plasmas at a toroidal magnetic field B T = 1.15 T, plasma current I p = 300 kA and line-averaged electron density n e = 5×10 19 m -3 . The data obtained between the ELMs were processed by the recently published first-derivative probe technique for precise determination of the plasma potential and the electron energy distribution function (EEDF). The spatial profile of the EEDF shows that at the high-field side it is Maxwellian with a temperature of 5 -- 10 eV. The electron temperatures and the ion-saturation current density obtained were used to evaluate the radial distribution of the parallel power flux density as being in the order of 0.05 -- 7 MW/m 2 . (paper)

Pediatric blood sample collection from a pre-existing peripheral intravenous (PIV) catheter.

Science.gov (United States)

Braniff, Heather; DeCarlo, Ann; Haskamp, Amy Corey; Broome, Marion E

2014-01-01

Aiming to minimize pain in a hospitalized child, the purpose of this observational study was to describe characteristics of blood samples collected from pre-existing peripheral intravenous (PIV) catheters in pediatric patients. One hundred and fifty blood samples were reviewed for number of unusable samples requiring a specimen to be re-drawn. Success of the blood draw and prevalence of the loss of the PIV following blood collection was also measured. Findings included one clotted specimen, success rate of 91.3%, and 1.3% of PIVs becoming non-functional after collection. Obtaining blood specimens from a pre-existing PIV should be considered in a pediatric patient. Copyright © 2014 Elsevier Inc. All rights reserved.

Plasma total antioxidant capacity is associated with dietary intake and plasma level of antioxidants in postmenopausal women.

Science.gov (United States)

Wang, Ying; Yang, Meng; Lee, Sang-Gil; Davis, Catherine G; Kenny, Anne; Koo, Sung I; Chun, Ock K

2012-12-01

Increased plasma total antioxidant capacity (TAC) has been associated with a high consumption of fruits and vegetables. However, limited information is available on whether plasma TAC reflects the dietary intake of antioxidants and the levels of individual antioxidants in plasma. By using three different assays, the study aimed to determine if plasma TAC can effectively predict dietary intake of antioxidants and plasma antioxidant status. Forty overweight and apparently healthy postmenopausal women were recruited. Seven-day food records and 12-h fasting blood samples were collected for dietary and plasma antioxidant assessments. Plasma TAC was determined by vitamin C equivalent antioxidant capacity (VCEAC), ferric-reducing ability of plasma (FRAP) and oxygen radical absorbance capacity (ORAC) assays. TAC values determined by VCEAC were highly correlated with FRAP (r=0.79, Pantioxidants and represents more closely the plasma antioxidant levels than ORAC and FRAP. Copyright © 2012 Elsevier Inc. All rights reserved.

Plasma sample based analysis of gastric cancer progression using targeted metabolomics.

Science.gov (United States)

Lario, Sergio; Ramírez-Lázaro, Maria José; Sanjuan-Herráez, Daniel; Brunet-Vega, Anna; Pericay, Carles; Gombau, Lourdes; Junquera, Félix; Quintás, Guillermo; Calvet, Xavier

2017-12-19

Gastric carcinogenesis is a multifactorial process described as a stepwise progression from non-active gastritis (NAG), chronic active gastritis (CAG), precursor lesions of gastric cancer (PLGC) and gastric adenocarcinoma. Gastric cancer (GC) 5-year survival rate is highly dependent upon stage of disease at diagnosis, which is based on endoscopy, biopsy and pathological examinations. Non-invasive GC biomarkers would facilitate its diagnosis at early stages leading to improved GC prognosis. We analyzed plasma samples collected from 80 patients diagnosed with NAG without H. pylori infection (NAG-), CAG with H. pylori infection (CAG+), PLGC and GC. A panel of 208 metabolites including acylcarnitines, amino acids and biogenic amines, sphingolipids, glycerophospholipids, hexoses, and tryptophan and phenylalanine metabolites were quantified using two complementary quantitative approaches: Biocrates AbsoluteIDQ®p180 kit and a LC-MS method designed for the analysis of 29 tryptophan pathway and phenylalanine metabolites. Significantly altered metabolic profiles were found in GC patients that allowing discrimination from NAG-, CAG+ and PLGC patients. Pathway analysis showed significantly altered tryptophan and nitrogen metabolic pathways (FDR P < 0.01). Three metabolites (histidine, tryprophan and phenylacetylglutamine) discriminated between non-GC and GC groups. These metabolic signatures open new possibilities to improve surveillance of PLGC patients using a minimally invasive blood analysis.

Collective laser light scattering from electron density fluctuations in fusion research plasmas (invited)

International Nuclear Information System (INIS)

Holzhauer, E.; Dodel, G.

1990-01-01

In magnetically confined plasmas density fluctuations of apparently turbulent nature with broad spectra in wave number and frequency space are observed which are thought to be the cause for anomalous energy and particle transport across the confining magnetic field. Collective laser light scattering has been used to study the nature of these fluctuations. Specific problems of scattering from fusion plasmas are addressed and illustrated with experimental results from the 119 μm far infrared laser scattering experiment operated on the ASDEX tokamak. Using the system in the heterodyne mode the direction of propagation with respect to the laboratory frame can be determined. Spatial resolution has bean improved by making use of the change in pitch of the total magnetic field across the minor plasma radius. Special emphasis is placed on the ohmic phase where a number of parameter variations including electron density, electron temperature, toroidal magnetic field, and filling gas were performed

Measurements of ion temperature and plasma hydrogenic composition by collective Thomson scattering in neutral beam heated discharges at TEXTOR

DEFF Research Database (Denmark)

Stejner Pedersen, Morten; Salewski, Mirko; Korsholm, Søren Bang

2013-01-01

A method is developed to perform plasma composition and ion temperature measurements across the plasma minor radius in TEXTOR based on ion cyclotron structures in collective Thomson scattering spectra. By gradually moving the scattering volume, we obtain measurements across the outer midplane of ...

Liquid sampling-atmospheric pressure glow discharge as a secondary excitation source: Assessment of plasma characteristics

Energy Technology Data Exchange (ETDEWEB)

Manard, Benjamin T. [Department of Chemistry, Clemson University, Clemson, SC 29634 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Gonzalez, Jhanis J. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Sarkar, Arnab [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Dong, Meirong; Chirinos, Jose; Mao, Xianglei; Russo, Richard E. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Marcus, R. Kenneth [Department of Chemistry, Clemson University, Clemson, SC 29634 (United States)

2014-04-01

The liquid sampling-atmospheric pressure glow discharge (LS-APGD) has been assessed as a secondary excitation source with a parametric evaluation regarding carrier gas flow rate, applied current, and electrode distance. With this parametric evaluation, plasma optical emission was monitored in order to obtain a fundamental understanding with regards to rotational temperature (T{sub rot}), excitation temperature (T{sub exc}), electron number density (n{sub e}), and plasma robustness. Incentive for these studies is not only for a greater overall fundamental knowledge of the APGD, but also in instrumenting a secondary excitation/ionization source following laser ablation (LA). Rotational temperatures were determined through experimentally fitting of the N{sub 2} and OH molecular emission bands while atomic excitation temperatures were calculated using a Boltzmann distribution of He and Mg atomic lines. The rotational and excitation temperatures were determined to be ∼ 1000 K and ∼ 2700 K respectively. Electron number density was calculated to be on the order of ∼ 3 × 10{sup 15} cm{sup −3} utilizing Stark broadening effects of the Hα line of the Balmer series and a He I transition. In addition, those diagnostics were performed introducing magnesium (by solution feed and laser ablation) into the plasma in order to determine any perturbation under heavy matrix sampling. The so-called plasma robustness factor, derived by monitoring Mg II/Mg I emission ratios, is also employed as a reflection of potential perturbations in microplasma energetics across the various operation conditions and sample loadings. While truly a miniaturized source (< 1 mm{sup 3} volume), the LS-APGD is shown to be quite robust with plasma characteristics and temperatures being unaffected upon introduction of metal species, whether by liquid or laser ablation sample introduction. - Highlights: • Liquid sampling-atmospheric pressure glow discharge (LS-APGD) • LS-APGD as a secondary

Interplay of single particle and collective response in molecular dynamics simulation of dusty plasma system

Science.gov (United States)

Maity, Srimanta; Das, Amita; Kumar, Sandeep; Tiwari, Sanat Kumar

2018-04-01

The collective response of the plasma medium is well known and has been explored extensively in the context of dusty plasma medium. On the other hand, the individual particle response associated with the collisional character giving rise to the dissipative phenomena has not been explored adequately. In this paper, two-dimensional molecular dynamics simulation of dust particles interacting via Yukawa potential has been considered. It has been shown that disturbances induced in a dust crystal elicit both collective and single particle responses. Generation of a few particles moving at speeds considerably higher than acoustic and/or shock speed (excited by the external disturbance) is observed. This is an indication of a single particle response. Furthermore, as these individual energetic particles propagate, the dust crystal is observed to crack along their path. Initially when the energy is high, these particles generate secondary energetic particles by the collisional scattering process. However, ultimately as these particles slow down they excite a collective response in the dust medium at secondary locations in a region which is undisturbed by the primary external disturbance. The condition when the cracking of the crystal stops and collective excitations get initiated has been identified quantitatively. The trailing collective primary disturbances would thus often encounter a disturbed medium with secondary and tertiary collective perturbations, thereby suffering significant modification in its propagation. It is thus clear that there is an interesting interplay (other than mere dissipation) between the single particle and collective response which governs the dynamics of any disturbance introduced in the medium.

Accuracy of recommended sampling and assay methods for the determination of plasma-free and urinary fractionated metanephrines in the diagnosis of pheochromocytoma and paraganglioma: a systematic review.

Science.gov (United States)

Därr, Roland; Kuhn, Matthias; Bode, Christoph; Bornstein, Stefan R; Pacak, Karel; Lenders, Jacques W M; Eisenhofer, Graeme

2017-06-01

To determine the accuracy of biochemical tests for the diagnosis of pheochromocytoma and paraganglioma. A search of the PubMed database was conducted for English-language articles published between October 1958 and December 2016 on the biochemical diagnosis of pheochromocytoma and paraganglioma using immunoassay methods or high-performance liquid chromatography with coulometric/electrochemical or tandem mass spectrometric detection for measurement of fractionated metanephrines in 24-h urine collections or plasma-free metanephrines obtained under seated or supine blood sampling conditions. Application of the Standards for Reporting of Diagnostic Studies Accuracy Group criteria yielded 23 suitable articles. Summary receiver operating characteristic analysis revealed sensitivities/specificities of 94/93% and 91/93% for measurement of plasma-free metanephrines and urinary fractionated metanephrines using high-performance liquid chromatography or immunoassay methods, respectively. Partial areas under the curve were 0.947 vs. 0.911. Irrespective of the analytical method, sensitivity was significantly higher for supine compared with seated sampling, 95 vs. 89% (p sampling compared with 24-h urine, 95 vs. 90% (p sampling, seated sampling, and urine. Test accuracy increased linearly from 90 to 93% for 24-h urine at prevalence rates of 0.0-1.0, decreased linearly from 94 to 89% for seated sampling and was constant at 95% for supine conditions. Current tests for the biochemical diagnosis of pheochromocytoma and paraganglioma show excellent diagnostic accuracy. Supine sampling conditions and measurement of plasma-free metanephrines using high-performance liquid chromatography with coulometric/electrochemical or tandem mass spectrometric detection provides the highest accuracy at all prevalence rates.

Measurement of GFR by Tc-99m DTPA: Comparison of 5 plasma sample and 2 plasma sample methods in North Indian population

International Nuclear Information System (INIS)

Mittal, B.R.; Bhattacharya, A.; Singh, B.; Jha, V.; Sarika, Kumar R.

2007-01-01

Assessment of Glomerular filtration rate (GFR) has significant impact on both prognosis and treatment of patients with renal disease. In this study we compared the two-plasma-sample method (G2S) using a MS excel spreadsheet based program, with a manual five-plasmasample method (GS) used to measure GFR by determining Tc-99m-diethylenetriamine penta-acetic acid (Tc-99m DTPA) clearance in patients with chronic kidney disease (CKD) and healthy renal donors. The study was conducted in 148 subjects (64 men and 84 women; age range 14 to 70 yr); 59 patients of CKD and 89 prospective healthy kidney donors. Tc-99m DTPA (74-100 MBq) was injected intravenously and thereafter blood samples were obtained at 60, 90, 120, 150 and 180 min via the patent venflon. Radioactivity in the injection syringe and plasma was measured by means of a multi-well gamma counter. The correlation coefficient between the 2 methods was 0.9453, with a slope of 0.90 and an intercept of 14.72 mL/min. Bland Altman plot of disagreement showed that G2S underestimated the GFR values by 9.0 ml/min, 11.3 ml/min and 6.9 ml/min, in the entire study, CKD and healthy donor groups respectively. Our results indicate that in spite of good correlation between GS and G2S method, the G2S method constantly underestimated GFR in our study population. However, regression equation may be applied to the GFR values estimated by G2S method to match the GFR determined by GS method. (author)

Direct determination of trace rare earth elements in ancient porcelain samples with slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Xiang Guoqiang; Jiang Zucheng; He Man; Hu Bin

2005-01-01

A method for the direct determination of trace rare earth elements in ancient porcelain samples by slurry sampling fluorinating electrothermal vaporization inductively coupled plasma mass spectrometry was developed with the use of polytetrafluoroethylene as fluorinating reagent. It was found that Si, as a main matrix element in ancient porcelain sample, could be mostly removed at the ashing temperature of 1200 deg. C without considerable losses of the analytes. However, the chemical composition of ancient porcelain sample is very complicated, which makes the influences resulting from other matrix elements not be ignored. Therefore, the matrix effect of ancient porcelain sample was also investigated, and it was found that the matrix effect is obvious when the matrix concentration was larger than 0.8 g l -1 . The study results of particle size effect indicated that when the sample particle size was less than 0.057 mm, the particle size effect is negligible. Under the optimized operation conditions, the detection limits for rare earth elements by fluorinating electrothermal vaporization inductively coupled plasma mass spectrometry were 0.7 ng g -1 (Eu)-33.3 ng g -1 (Nd) with the precisions of 4.1% (Yb)-10% (La) (c = 1 μg l -1 , n = 9). The proposed method was used to directly determine the trace rare earth elements in ancient porcelain samples produced in different dynasty (Sui, Ming and Qing), and the analytical results are satisfactory

Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

Energy Technology Data Exchange (ETDEWEB)

Rapp, Juergen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Aaron, A. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bell, Gary L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burgess, Thomas W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ellis, Ronald James [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Giuliano, D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kiggans, James O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lessard, Timothy L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ohriner, Evan Keith [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Perkins, Dale E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Varma, Venugopal Koikal [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-10-20

-state heat fluxes of 5–20 MW/m² and ion fluxes up to 10²⁴ m^-2s^-1. Since PFCs will have to withstand neutron irradiation displacement damage up to 50 dpa, the target station design must accommodate radioactive specimens (materials to be irradiated in HFIR or at SNS) to enable investigations of the impact of neutron damage on materials. Therefore, the system will have to be able to install and extract irradiated specimens using equipment and methods to avoid sample modification, control contamination, and minimize worker dose. Included in the design considerations will be an assessment of all the steps between neutron irradiation and post-exposure materials examination/characterization, as well as an evaluation of the facility hazard categorization. In particular, the factors associated with the acquisition of radioactive specimens and their preparation, transportation, experimental configuration at the plasma-specimen interface, post-plasma-exposure sample handling, and specimen preparation will be evaluated. Neutronics calculations to determine the dose rates of the samples were carried out for a large number of potential plasma-facing materials.

IMPROVEMENT OF METHODS FOR HYDROBIOLOGICAL RESEARCH AND MODIFICATION OF STANDARD TOOLS FOR SAMPLE COLLECTION

Directory of Open Access Journals (Sweden)

M. M. Aligadjiev

2015-01-01

Full Text Available Aim. The paper discusses the improvement of methods of hydrobiological studies by modifying tools for plankton and benthic samples collecting. Methods. In order to improve the standard methods of hydro-biological research, we have developed tools for sampling zooplankton and benthic environment of the Caspian Sea. Results. Long-term practice of selecting hydrobiological samples in the Caspian Sea shows that it is required to complete the modernization of the sampling tools used to collect hydrobiological material. With the introduction of Azov and Black Sea invasive comb jelly named Mnemiopsis leidyi A. Agassiz to the Caspian Sea there is a need to collect plankton samples without disturbing its integrity. Tools for collecting benthic fauna do not always give a complete picture of the state of benthic ecosystems because of the lack of visual site selection for sampling. Moreover, while sampling by dredge there is a probable loss of the samples, especially in areas with difficult terrain. Conclusion. We propose to modify a small model of Upstein net (applied in shallow water to collect zooplankton samples with an upper inverted cone that will significantly improve the catchability of the net in theCaspian Sea. Bottom sampler can be improved by installing a video camera for visual inspection of the bottom topography, and use sensors to determine tilt of the dredge and the position of the valves of the bucket. 

Quantitative plasma biomarker analysis in HDI exposure assessment.

Science.gov (United States)

Flack, Sheila L; Fent, Kenneth W; Trelles Gaines, Linda G; Thomasen, Jennifer M; Whittaker, Steve; Ball, Louise M; Nylander-French, Leena A

2010-01-01

Quantification of amines in biological samples is important for evaluating occupational exposure to diisocyanates. In this study, we describe the quantification of 1,6-hexamethylene diamine (HDA) levels in hydrolyzed plasma of 46 spray painters applying 1,6-hexamethylene diisocyanate (HDI)-containing paint in vehicle repair shops collected during repeated visits to their workplace and their relationship with dermal and inhalation exposure to HDI monomer. HDA was detected in 76% of plasma samples, as heptafluorobutyryl derivatives, and the range of HDA concentrations was HDA levels and HDI inhalation exposure measured on the same workday was low (N = 108, r = 0.22, P = 0.026) compared with the correlation between plasma HDA levels and inhalation exposure occurring approximately 20 to 60 days before blood collection (N = 29, r = 0.57, P = 0.0014). The correlation between plasma HDA levels and HDI dermal exposure measured on the same workday, although statistically significant, was low (N = 108, r = 0.22, P = 0.040) while the correlation between HDA and dermal exposure occurring approximately 20 to 60 days before blood collection was slightly improved (N = 29, r = 0.36, P = 0.053). We evaluated various workplace factors and controls (i.e. location, personal protective equipment use and paint booth type) as modifiers of plasma HDA levels. Workers using a downdraft-ventilated booth had significantly lower plasma HDA levels relative to semi-downdraft and crossdraft booth types (P = 0.0108); this trend was comparable to HDI inhalation and dermal exposure levels stratified by booth type. These findings indicate that HDA concentration in hydrolyzed plasma may be used as a biomarker of cumulative inhalation and dermal exposure to HDI and for investigating the effectiveness of exposure controls in the workplace.

Analyses of metallic first mirror samples after long term plasma exposure in Tore Supra

International Nuclear Information System (INIS)

Lipa, M.; Schunke, B.; Gil, Ch.; Bucalossi, J.; Voitsenya, V.S.; Konovalov, V.; Vukolov, K.; Balden, M.; De Temmerman, G.; Oelhafen, P.; Litnovsky, A.; Wienhold, P.

2006-01-01

Metallic mirrors are foreseen in ITER diagnostic systems as optical elements directly viewing the plasma radiation. In the frame of an EFDA contract, metallic mirror samples have been exposed for long pulse plasma discharges in Tore Supra (TS) in order to investigate surface modifications caused by erosion and re-deposition processes. Three different materials have been selected: mono-crystalline molybdenum (mc-Mo), polycrystalline stainless steel (SS) and copper (Cu). The mc-Mo samples showed after TS exposure almost no surface roughness modifications and the lowest net-erosion. A slight reflectivity reduction, most pronounced in the near UV, is attributed to light absorption in a thin carbon deposit. Cu mirrors showed by far the highest surface roughness, erosion and diffusive reflectivity. Comparative laboratory glow discharge experiments with virgin reference samples and numerical simulations of erosion/deposition confirm the dominant contribution of conditioning procedures to erosion of mirrors exposed (without shutter protection) in Tore Supra

Determination of the pyrethroid insecticide metabolite 3-PBA in plasma and urine samples from farmer and consumer groups in northern Thailand

Science.gov (United States)

THIPHOM, SARUNYA; PRAPAMONTOL, TIPPAWAN; CHANTARA, SOMPORN; MANGKLABRUKS, AMPICA; SUPHAVILAI, CHAISUREE; AHN, KI CHANG; GEE, SHIRLEY J.; HAMMOCK, BRUCE D.

2014-01-01

In this study, the enzyme-linked immunosorbent assays (ELISA) were modified to detect 3-PBA in plasma (including the adducted form) and urine among a large group of consumers and farmers in an agricultural area. The samples were collected on the same day in the morning from 100 consumers (50 females, 50 males) and 100 farmers (50 females, 50 males) in the Fang district, Chiang Mai province, northern Thailand. The ELISA was very sensitive having an IC50 value of 26.7 and 15.3 ng/mL, a limit of quantitation of 5 and 2.5 ng/mL and a limit of detection of 1.08 and 1.94 ng/mL for plasma and urine, respectively. These methods had low (< 5%) intra- and inter-assay coefficients of variation. The extraction technique satisfactorily eliminated the matrix effect from samples before ELISA analysis, yielding good recoveries (85.9–99.4% and 87.3–98.0%, respectively). For the volunteer study, the detection rate for plasma 3-PBA was 24% in consumers and 42% in farmers, but the median and range values were similar (median 5.87 ng/mL, range 5.16–8.44 ng/mL in consumers and 6.27 ng/mL, range 4.29–9.57 ng/mL in farmers). The rate of detection in the urine was similar (76% and 69%, in consumers and in farmers), yet the median concentration was significantly higher in farmers (8.86 μg/g creatinine in consumers vs 16.1 μg/g creatinine in farmers) and the range also much wider in farmers (1.62–80.5 μg/g creatinine in consumers and 0.80–256.2 μg/g creatinine in farmers). There was no correlation between plasma 3-PBA and urinary 3-PBA concentrations in the study presumably because plasma 3-PBA is a measure of cumulative exposures while urinary 3-PBA reflects acute exposures. In addition, metabolism and excretion of pyrethroids varies by individual. Nevertheless, this study demonstrated that these volunteers were exposed to pyrethroids. To our knowledge, this is the first report that compared plasma 3-PBA and urinary 3-PBA in a large group of volunteers. The ELISA method

Prediction of two-sample 99mTc-diethylene triamine pentaacetic acid plasma clearance from single-sample method

International Nuclear Information System (INIS)

Zuo Li; Ma Ying-Chun; Wang Mei; Zhang Chun-Li; Wang Rong-Fu; Wang Hai-Yan

2005-01-01

The objective of this study was to develop an equation to predict dual plasma sample method (DPSM) 99m Tc-diethylene triamine pentaacetic acid ( 99m Tc-DTPA) plasma clearance from single plasma sample method (SPSM), and to clarify the condition in which DPSM can be substituted by SPSM in measurement of glomerular filtration rate (GFR). Patients with chronic kidney disease (CKD) were selected. Watson modified Christensen and Groth equation was used to calculate 99m Tc-DTPA plasma clearance by SPSM (sGFR). The equation recommended by the Nephrourology Committee of the Society of Nuclear Medicine was used to calculate 99m Tc-DTPA plasma clearance by DPSM (tGFR) in each patient. The difference between sGFR and tGFR was expressed as percent of the average of these two methods, and tGFR was predicted from sGFR. Plasma creatinine was measured by the kinetic picrate method, and GFR estimated by abbreviated modification of diet in renal disease (MDRD) equation (aGFR) and Cockcroft-Gault equation (cGFR) were evaluated as criteria in selection of DPSM and SPSM. Three hundred and sixty-nine patients with CKD were selected (208 male and 161 female). The average age and body weight were 51.4±15.5 years and 67.2±12.5 kg, respectively. The causes of CKD were glomerular disease, renal arterial stenosis, chronic tubulointerstitial disease, and other causes or causes unknown. The average tGFR was 62.9±36.5 ml/min/1.73 m 2 , ranging from 1-180 ml/min/1.73 m 2 . sGFR was significantly correlated with tGFR (r=0.9194, p 2 ; in contrast, then tGFR was±30 ml/min/1.73 m 2 , the difference was constant (-1.1%, 95% confidence interval -18.3%, 16.1%), and tGFR could be predicted from sGFR using the equation: predicted tGFR (ml/min/1.73 m 2 )=7 4244+0.7318 x sGFR+0.0022 x sGFR 2 (n=299, r 2 =0.9428, p 2 , the diagnostic sensitivity of a cut off value of aGFR=45 ml/min/1.73 m 2 was 91.8%, and recommended as a criterion in the selection of DPSM and SPSM. When GFR ≥30 ml/min/1.73 m 2 , t

Human blood RNA stabilization in samples collected and transported for a large biobank

Science.gov (United States)

2012-01-01

Background The Norwegian Mother and Child Cohort Study (MoBa) is a nation-wide population-based pregnancy cohort initiated in 1999, comprising more than 108.000 pregnancies recruited between 1999 and 2008. In this study we evaluated the feasibility of integrating RNA analyses into existing MoBa protocols. We compared two different blood RNA collection tube systems – the PAXgene™ Blood RNA system and the Tempus™ Blood RNA system - and assessed the effects of suboptimal blood volumes in collection tubes and of transportation of blood samples by standard mail. Endpoints to characterize the samples were RNA quality and yield, and the RNA transcript stability of selected genes. Findings High-quality RNA could be extracted from blood samples stabilized with both PAXgene and Tempus tubes. The RNA yields obtained from the blood samples collected in Tempus tubes were consistently higher than from PAXgene tubes. Higher RNA yields were obtained from cord blood (3 – 4 times) compared to adult blood with both types of tubes. Transportation of samples by standard mail had moderate effects on RNA quality and RNA transcript stability; the overall RNA quality of the transported samples was high. Some unexplained changes in gene expression were noted, which seemed to correlate with suboptimal blood volumes collected in the tubes. Temperature variations during transportation may also be of some importance. Conclusions Our results strongly suggest that special collection tubes are necessary for RNA stabilization and they should be used for establishing new biobanks. We also show that the 50,000 samples collected in the MoBa biobank provide RNA of high quality and in sufficient amounts to allow gene expression analyses for studying the association of disease with altered patterns of gene expression. PMID:22988904

Collection and preparation of water samples for hydrogeochemical reconnaissance

International Nuclear Information System (INIS)

Baucom, E.I.; Ferguson, R.B.; Wallace, R.M.

1977-01-01

A method based on ion exchange and neutron activation analysis (NAA) was developed and field-tested to determine uranium over the range 0.02 to 10,000 ppb in natural water using a single procedure. Water samples are filtered in the field using a specially-designed one-liter filter apparatus pressurized to 40 psig with an inert gas. The filtered water is treated with a high purity, mixed cation-anion resin in the hydronium-hydroxide form. All ions are removed from solution under the strong driving force of the neutralization reaction. Anionic, cationic, and natural complexes of uranium can be concentrated with this method. Field tests showed greater than 95 percent recovery of 13 elements analyzed (including greater than 99 percent recovery of uranium) and greater than or equal to 90 percent recovery of 4 other elements. Uranium collected on the resin was quantitatively determined by NAA. Coefficient of variation for sampling plus analysis was less than 20 percent for samples containing more than 0.1 ppb uranium. Advantages of this method include: (1) wide dynamic range, (2) low detection limit for uranium (0.02 ppb), (3) high precision and accuracy, (4) relatively low cost, (5) high-yield recovery from low-level aqueous samples without risk of loss to containers, (6) decreased risk of significant sample contamination compared with other low-level methods, (7) production of stable samples suitable for retrievable storage, and(8) concentration of other ions that can be determined by NAA. This paper presents (1) background regarding development of procedures for sample collection and preparation, (2) results of development programs, (3) description of equipment and field procedures, and (4) preliminary conclusions regarding use of this technology for hydrogeochemical reconnaissance for uranium

Nonthermal plasmas around black holes, relevant collective modes, new configurations, and magnetic field amplification

Energy Technology Data Exchange (ETDEWEB)

Coppi, B., E-mail: coppi@mit.edu [Massachusetts Institute of Technology (United States)

2017-03-15

The radiation emission from Shining Black Holes is most frequently observed to have nonthermal features. It is therefore appropriate to consider relevant collective processes in plasmas surrounding black holes that contain high energy particles with nonthermal distributions in momentum space. A fluid description with significant temperature anisotropies is the simplest relevant approach. These anisotropies are shown to have a critical influence on: (a) the existence and characteristics of stationary plasma and field ring configurations, (b) the excitation of “thermo-gravitational modes” driven by temperature anisotropies and gradients that involve gravity and rotation, (c) the generation of magnetic fields over macroscopic scale distances, and (d) the transport of angular momentum.

Stability of BDNF in Human Samples Stored Up to 6 Months and Correlations of Serum and EDTA-Plasma Concentrations.

Science.gov (United States)

Polyakova, Maryna; Schlögl, Haiko; Sacher, Julia; Schmidt-Kassow, Maren; Kaiser, Jochen; Stumvoll, Michael; Kratzsch, Jürgen; Schroeter, Matthias L

2017-06-03

Brain-derived neurotrophic factor (BDNF), an important neural growth factor, has gained growing interest in neuroscience, but many influencing physiological and analytical aspects still remain unclear. In this study we assessed the impact of storage time at room temperature, repeated freeze/thaw cycles, and storage at -80 °C up to 6 months on serum and ethylenediaminetetraacetic acid (EDTA)-plasma BDNF. Furthermore, we assessed correlations of serum and plasma BDNF concentrations in two independent sets of samples. Coefficients of variations (CVs) for serum BDNF concentrations were significantly lower than CVs of plasma concentrations ( n = 245, p = 0.006). Mean serum and plasma concentrations at all analyzed time points remained within the acceptable change limit of the inter-assay precision as declared by the manufacturer. Serum and plasma BDNF concentrations correlated positively in both sets of samples and at all analyzed time points of the stability assessment ( r = 0.455 to r s = 0.596; p plasma up to 6 months. Due to a higher reliability, we suggest favoring serum over EDTA-plasma for future experiments assessing peripheral BDNF concentrations.

Ex vivo spontaneous generation of 19-norandrostenedione and nandrolone detected in equine plasma and urine.

Science.gov (United States)

Guan, Fuyu; Uboh, Cornelius E; Soma, Lawrence R; You, Youwen; Li, Xiaoqing; McDonnell, Sue

2012-01-01

19-Norandrostenedione (NAED) and nandrolone are anabolic-androgenic steroids (AASs). Nandrolone was regarded solely as a synthetic AAS until the 1980s when trace concentrations of apparently endogenous nandrolone were detected in urine samples obtained from intact male horses (stallions). Since then, its endogenous origin has been reported in boars and bulls; endogenous NAED and nandrolone have been identified in plasma and urine samples collected from stallions. More recently, however, it was suggested that NAED and nandrolone detected in urine samples from stallions are primarily artifacts due to the analytical procedure. The present study was undertaken to determine whether NAED and nandrolone detected in plasma and urine samples collected from stallions are truly endogenous or artifacts from sample processing. To answer this question, fresh plasma and urine samples from ≥8 stallions were analyzed for the two AASs, soon after collection, by liquid chromatography hyphenated to tandem mass spectrometry (LC-MS/MS). NAED and nandrolone were not detected in fresh plasma samples but detected in the same samples post storage. Concentrations of both AASs increased with storage time, and the increases were greater at a higher storage temperature (37°C versus 4°C, and ambient temperature versus 4°C). Although NAED was detected in some fresh stallion urine samples, its concentration (samples post storage (at ambient temperature for 15 days). Nandrolone was not detected in most of fresh urine samples but detected in the same samples post storage. Based on these results, it is concluded that all NAED and nandrolone detected in stored plasma samples of stallions and most of them in the stored urine samples are not from endogenous origins but spontaneously generated during sample storage, most likely from spontaneous decarboxylation of androstenedione-19-oic acid and testosterone-19-oic acid. To our knowledge, it is the first time that all NAED and nandrolone detected in

Blood venous sample collection: Recommendations overview and a checklist to improve quality.

Science.gov (United States)

Giavarina, Davide; Lippi, Giuseppe

2017-07-01

The extra-analytical phases of the total testing process have substantial impact on managed care, as well as an inherent high risk of vulnerability to errors which is often greater than that of the analytical phase. The collection of biological samples is a crucial preanalytical activity. Problems or errors occurring shortly before, or soon after, this preanalytical step may impair sample quality and characteristics, or else modify the final results of testing. The standardization of fasting requirements, rest, patient position and psychological state of the patient are therefore crucial for mitigating the impact of preanalytical variability. Moreover, the quality of materials used for collecting specimens, along with their compatibility, can guarantee sample quality and persistence of chemical and physical characteristics of the analytes over time, so safeguarding the reliability of testing. Appropriate techniques and sampling procedures are effective to prevent problems such as hemolysis, undue clotting in the blood tube, draw of insufficient sample volume and modification of analyte concentration. An accurate identification of both patient and blood samples is a key priority as for other healthcare activities. Good laboratory practice and appropriate training of operators, by specifically targeting collection of biological samples, blood in particular, may greatly improve this issue, thus lowering the risk of errors and their adverse clinical consequences. The implementation of a simple and rapid check-list, including verification of blood collection devices, patient preparation and sampling techniques, was found to be effective for enhancing sample quality and reducing some preanalytical errors associated with these procedures. The use of this tool, along with implementation of objective and standardized systems for detecting non-conformities related to unsuitable samples, can be helpful for standardizing preanalytical activities and improving the quality of

Radiometric-microbiologic assay fo vitamin B-6: analysis of plasma samples

International Nuclear Information System (INIS)

Guilarte, T.R.; McIntyre, P.A.

1981-01-01

A radiometric microbiologic assay for the analysis of vitamin B-6 in plasma was developed. The method is based on the measurement of 14CO2 generated from the metabolism of DL-l-14C-valine (L-l-14C-valine) by Kloeckera brevis. The assay is specific for the biologically active forms of the vitamin, that is, pyridoxine, pyridoxal and pyridoxamine, and their respective phosphorylated forms. The biologically inert vitamin B-6 metabolite (4-pyridoxic acid) did not generate a response at concentrations tested. The radiometric technique was shown to be sensitive to the 1 nanogram level. Reproducibility and recovery studies gave good results. Fifteen plasma samples were assayed using the radiometric and turbidimetric techniques. The correlation coefficient was r . 0.98. Turbid material or precipitated debris did not interfere with the radiometric microbiologic assay, thus allowing for simplification of assay procedure

Flow induced dispersion analysis rapidly quantifies proteins in human plasma samples

DEFF Research Database (Denmark)

Poulsen, Nicklas N; Andersen, Nina Z; Østergaard, Jesper

2015-01-01

Rapid and sensitive quantification of protein based biomarkers and drugs is a substantial challenge in diagnostics and biopharmaceutical drug development. Current technologies, such as ELISA, are characterized by being slow (hours), requiring relatively large amounts of sample and being subject...... to cumbersome and expensive assay development. In this work a new approach for quantification based on changes in diffusivity is presented. The apparent diffusivity of an indicator molecule interacting with the protein of interest is determined by Taylor Dispersion Analysis (TDA) in a hydrodynamic flow system...... in a blood plasma matrix), fully automated, and being subject to a simple assay development. FIDA is demonstrated for quantification of the protein Human Serum Albumin (HSA) in human plasma as well as for quantification of an antibody against HSA. The sensitivity of the FIDA assay depends on the indicator...

Simultaneous determination of CRP and D-dimer in human blood plasma samples with White Light Reflectance Spectroscopy.

Science.gov (United States)

Koukouvinos, Georgios; Petrou, Panagiota; Misiakos, Konstantinos; Drygiannakis, Dimitris; Raptis, Ioannis; Stefanitsis, Gerasimos; Martini, Spyridoula; Nikita, Dimitra; Goustouridis, Dimitrios; Moser, Isabella; Jobst, Gerhard; Kakabakos, Sotirios

2016-10-15

A dual-analyte assay for the simultaneous determination of C-reactive protein (CRP) and D-dimer in human blood plasma based on a white light interference spectroscopy sensing platform is presented. Measurement is accomplished in real-time by scanning the sensing surface, on which distinct antibody areas have been created, with a reflection probe used both for illumination of the surface and collection of the reflected interference spectrum. The composition of the transducer, the sensing surface chemical activation and biofunctionalization procedures were optimized with respect to signal magnitude and repeatability. The assay format involved direct detection of CRP whereas for D-dimer a two-site immunoassay employing a biotinylated reporter antibody and reaction with streptavidin was selected. The assays were sensitive with detection limits of 25ng/mL for both analytes, precise with intra- and inter-assay CV values ranging from 3.6% to 7.7%, and from 4.8% to 9.5%, respectively, for both assays, and accurate with recovery values ranging from 88.5% to 108% for both analytes. Moreover, the values determined for the two analytes in 35 human plasma samples were in excellent agreement with those received for the same samples by standard diagnostic laboratory instrumentation employing commercial kits. The excellent agreement of the results supported the validity of the proposed system for clinical application for the detection of multiple analytes since it was demonstrated that up to seven antibody areas can be created on the sensing surface and successfully interrogated with the developed optical set-up. Copyright © 2015. Published by Elsevier B.V.

The Autism Simplex Collection : an international, expertly phenotyped autism sample for genetic and phenotypic analyses

OpenAIRE

Buxbaum, Joseph D.; Bolshakova, Nadia; Brownfeld, Jessica M.; Anney, Richard J. L.; Bender, Patrick; Bernier, Raphael; Cook, Edwin H.; Coon, Hilary; Cuccaro, Michael L.; Freitag, Christine M.; Hallmayer, Joachim; Geschwind, Daniel H.; Klauck, Sabine M.; Nurnberger, John I.; Oliveira, Guiomar

2014-01-01

Background: There is an urgent need for expanding and enhancing autism spectrum disorder (ASD) samples, in order to better understand causes of ASD. Methods: In a unique public-private partnership, 13 sites with extensive experience in both the assessment and diagnosis of ASD embarked on an ambitious, 2-year program to collect samples for genetic and phenotypic research and begin analyses on these samples. The program was called The Autism Simplex Collection (TASC). TASC sample collection ...

[Logistics of collection and transportation of biological samples and the organization of the central laboratory in the ELSA-Brasil].

Science.gov (United States)

Fedeli, Ligia G; Vidigal, Pedro G; Leite, Claudia Mendes; Castilhos, Cristina D; Pimentel, Robércia Anjos; Maniero, Viviane C; Mill, Jose Geraldo; Lotufo, Paulo A; Pereira, Alexandre C; Bensenor, Isabela M

2013-06-01

The ELSA (Estudo Longitudinal de Saúde do Adulto - Brazilian Longitudinal Study for Adult Health) is a multicenter cohort study which aims at the identification of risk factors associated with type 2 diabetes and cardiovascular diseases in the Brazilian population. The paper describes the strategies for the collection, processing, transportation, and quality control of blood and urine tests in the ELSA. The study decided to centralize the tests at one single laboratory. The processing of the samples was performed at the local laboratories, reducing the weight of the material to be transported, and diminishing the costs of transportation to the central laboratory at the Universidade de São Paulo Hospital. The study included tests for the evaluation of diabetes, insulin resistance, dyslipidemia, electrolyte abnormalities, thyroid hormones, uric acid, hepatic enzyme abnormalities, inflammation, and total blood cell count. In addition, leukocyte DNA, urine, plasma and serum samples were stored. The central laboratory performed approximately 375,000 tests.

Identification of clinical biomarkers for pre-analytical quality control of blood samples.

Science.gov (United States)

Kang, Hyun Ju; Jeon, Soon Young; Park, Jae-Sun; Yun, Ji Young; Kil, Han Na; Hong, Won Kyung; Lee, Mee-Hee; Kim, Jun-Woo; Jeon, Jae-Pil; Han, Bok Ghee

2013-04-01

Pre-analytical conditions are key factors in maintaining the high quality of biospecimens. They are necessary for accurate reproducibility of experiments in the field of biomarker discovery as well as achieving optimal specificity of laboratory tests for clinical diagnosis. In research at the National Biobank of Korea, we evaluated the impact of pre-analytical conditions on the stability of biobanked blood samples by measuring biochemical analytes commonly used in clinical laboratory tests. We measured 10 routine laboratory analytes in serum and plasma samples from healthy donors (n = 50) with a chemistry autoanalyzer (Hitachi 7600-110). The analyte measurements were made at different time courses based on delay of blood fractionation, freezing delay of fractionated serum and plasma samples, and at different cycles (0, 1, 3, 6, 9) of freeze-thawing. Statistically significant changes from the reference sample mean were determined using the repeated-measures ANOVA and the significant change limit (SCL). The serum levels of GGT and LDH were changed significantly depending on both the time interval between blood collection and fractionation and the time interval between fractionation and freezing of serum and plasma samples. The glucose level was most sensitive only to the elapsed time between blood collection and centrifugation for blood fractionation. Based on these findings, a simple formula (glucose decrease by 1.387 mg/dL per hour) was derived to estimate the length of time delay after blood collection. In addition, AST, BUN, GGT, and LDH showed sensitive responses to repeated freeze-thaw cycles of serum and plasma samples. These results suggest that GGT and LDH measurements can be used as quality control markers for certain pre-analytical conditions (eg, delayed processing or repeated freeze-thawing) of blood samples which are either directly used in the laboratory tests or stored for future research in the biobank.

Detection of hemophilia A carriers by use of frozen plasma samples

International Nuclear Information System (INIS)

Yang, H.C.; Hardin, J.; Vaudreuil, C.

1978-01-01

The efficacy of using promptly frozen plasma samples in the diagnosis of the carrier state for hemophilia A was evaluated by simultaneous measurement of factor VIII activity and antigen in 20 normal women and 20 obligate carriers. Factor VIII antigen was measured by two methods, electroimmunoassay and immunoradiometric assay. When the factor VIII activity and antigen data were evaluated by regression analysis, 94% of the carriers were correctly identified at the 95% confidence level

Activity Concentration for Surface Soil Samples Collected from Arrant, Qena, Egypt

International Nuclear Information System (INIS)

Harb, S.; Salahel Din, K.; Abbady, A.; Moustafa, M.

2010-01-01

Soil samples were collected from four regions from Armant area. Qena, Upper Egypt for measure their natural radioactivity concentrations due to Ra-226, Th-232 and K-40 radionuclides. Thirty-Four surface soil samples were analyzed by using low-level gamma-spectrometric analysis. The average activity concentration for Ra-226 in (Bq/kg) in the collected soil samples were found to be 27.3 ±3.2, 11.4±1.09, 10.6±1.2, and 11.4±1.02 while the average value for Th-232 were 15.1±1.4, 11.1±0.77, 10.8 ± 0.72 and 11.1 ± 0.8 (Bq/kg) for soil samples from North, South, West and East. The corresponding average values for K-40 were 521.4±16.8, 463±14.8, 488.9±15.6 and 344.5±10.7 (Bq/kg), respectively. Based on radionuclides concentration in surface soil samples the radiological effects can be assessed

Probing Leader Cells in Endothelial Collective Migration by Plasma Lithography Geometric Confinement.

Science.gov (United States)

Yang, Yongliang; Jamilpour, Nima; Yao, Baoyin; Dean, Zachary S; Riahi, Reza; Wong, Pak Kin

2016-03-03

When blood vessels are injured, leader cells emerge in the endothelium to heal the wound and restore the vasculature integrity. The characteristics of leader cells during endothelial collective migration under diverse physiological conditions, however, are poorly understood. Here we investigate the regulation and function of endothelial leader cells by plasma lithography geometric confinement generated. Endothelial leader cells display an aggressive phenotype, connect to follower cells via peripheral actin cables and discontinuous adherens junctions, and lead migrating clusters near the leading edge. Time-lapse microscopy, immunostaining, and particle image velocimetry reveal that the density of leader cells and the speed of migrating clusters are tightly regulated in a wide range of geometric patterns. By challenging the cells with converging, diverging and competing patterns, we show that the density of leader cells correlates with the size and coherence of the migrating clusters. Collectively, our data provide evidence that leader cells control endothelial collective migration by regualting the migrating clusters.

An international study of the performance of sample collection from patients

NARCIS (Netherlands)

Dzik, WH; Murphy, MF; Andreu, G; Heddle, N; Hogman, C; Kekomaki, R; Murphy, S; Shimizu, M; Smit Sibinga, C.T.

2003-01-01

Background and Objectives Collection of a blood sample from the correct patient is the first step in the process of safe transfusion. The aim of this international collaborative study was to assess the frequency of mislabelled and miscollected samples drawn for blood grouping. Materials and Methods

Estimation of reference intervals from small samples: an example using canine plasma creatinine.

Science.gov (United States)

Geffré, A; Braun, J P; Trumel, C; Concordet, D

2009-12-01

According to international recommendations, reference intervals should be determined from at least 120 reference individuals, which often are impossible to achieve in veterinary clinical pathology, especially for wild animals. When only a small number of reference subjects is available, the possible bias cannot be known and the normality of the distribution cannot be evaluated. A comparison of reference intervals estimated by different methods could be helpful. The purpose of this study was to compare reference limits determined from a large set of canine plasma creatinine reference values, and large subsets of this data, with estimates obtained from small samples selected randomly. Twenty sets each of 120 and 27 samples were randomly selected from a set of 1439 plasma creatinine results obtained from healthy dogs in another study. Reference intervals for the whole sample and for the large samples were determined by a nonparametric method. The estimated reference limits for the small samples were minimum and maximum, mean +/- 2 SD of native and Box-Cox-transformed values, 2.5th and 97.5th percentiles by a robust method on native and Box-Cox-transformed values, and estimates from diagrams of cumulative distribution functions. The whole sample had a heavily skewed distribution, which approached Gaussian after Box-Cox transformation. The reference limits estimated from small samples were highly variable. The closest estimates to the 1439-result reference interval for 27-result subsamples were obtained by both parametric and robust methods after Box-Cox transformation but were grossly erroneous in some cases. For small samples, it is recommended that all values be reported graphically in a dot plot or histogram and that estimates of the reference limits be compared using different methods.

Robustness of solvent/detergent treatment of plasma derivatives: a data collection from Plasma Protein Therapeutics Association member companies.

Science.gov (United States)

Dichtelmüller, Herbert O; Biesert, Lothar; Fabbrizzi, Fabrizio; Gajardo, Rodrigo; Gröner, Albrecht; von Hoegen, Ilka; Jorquera, Juan I; Kempf, Christoph; Kreil, Thomas R; Pifat, Dominique; Osheroff, Wendy; Poelsler, Gerhard

2009-09-01

Solvent/detergent (S/D) treatment is an established virus inactivation technology that has been applied in the manufacture of medicinal products derived from human plasma for more than 20 years. Data on the inactivation of enveloped viruses by S/D treatment collected from seven Plasma Protein Therapeutics Association member companies demonstrate the robustness, reliability, and efficacy of this virus inactivation method. The results from 308 studies reflecting production conditions as well as technical variables significantly beyond the product release specification were evaluated for virus inactivation, comprising different combinations of solvent and detergent (tri(n-butyl) phosphate [TNBP]/Tween 80, TNBP/Triton X-100, TNBP/Na-cholate) and different products (Factor [F]VIII, F IX, and intravenous and intramuscular immunoglobulins). Neither product class, process temperature, protein concentration, nor pH value has a significant impact on virus inactivation. A variable that did appear to be critical was the concentration of solvent and detergent. The data presented here demonstrate the robustness of virus inactivation by S/D treatment for a broad spectrum of enveloped test viruses and process variables. Our data substantiate the fact that no transmission of viruses such as human immunodeficiency virus, hepatitis B virus, hepatitis C virus, or of other enveloped viruses was reported for licensed plasma derivatives since the introduction of S/D treatment.

Novel liquid chromatography method based on linear weighted regression for the fast determination of isoprostane isomers in plasma samples using sensitive tandem mass spectrometry detection.

Science.gov (United States)

Aszyk, Justyna; Kot, Jacek; Tkachenko, Yurii; Woźniak, Michał; Bogucka-Kocka, Anna; Kot-Wasik, Agata

2017-04-15

A simple, fast, sensitive and accurate methodology based on a LLE followed by liquid chromatography-tandem mass spectrometry for simultaneous determination of four regioisomers (8-iso prostaglandin F 2α , 8-iso-15(R)-prostaglandin F 2α , 11β-prostaglandin F 2α , 15(R)-prostaglandin F 2α ) in routine analysis of human plasma samples was developed. Isoprostanes are stable products of arachidonic acid peroxidation and are regarded as the most reliable markers of oxidative stress in vivo. Validation of method was performed by evaluation of the key analytical parameters such as: matrix effect, analytical curve, trueness, precision, limits of detection and limits of quantification. As a homoscedasticity was not met for analytical data, weighted linear regression was applied in order to improve the accuracy at the lower end points of calibration curve. The detection limits (LODs) ranged from 1.0 to 2.1pg/mL. For plasma samples spiked with the isoprostanes at the level of 50pg/mL, intra-and interday repeatability ranged from 2.1 to 3.5% and 0.1 to 5.1%, respectively. The applicability of the proposed approach has been verified by monitoring of isoprostane isomers level in plasma samples collected from young patients (n=8) subjected to hyperbaric hyperoxia (100% oxygen at 280kPa(a) for 30min) in a multiplace hyperbaric chamber. Copyright © 2017 Elsevier B.V. All rights reserved.

Relationship between plasma uridine and urinary urea excretion.

Science.gov (United States)

Ka, Tuneyoshi; Inokuchi, Taku; Tamada, Daisuke; Suda, Michio; Tsutsumi, Zenta; Okuda, Chihiro; Yamamoto, Asako; Takahashi, Sumio; Moriwaki, Yuji; Yamamoto, Tetsuya

2010-03-01

To investigate whether the concentration of uridine in plasma is related to the urinary excretion of urea, 45 healthy male subjects with normouricemia and normal blood pressure were studied after providing informed consent. Immediately after collection of 24-hour urine, blood samples were drawn after an overnight fast except for water. The contents of ingested foods during the 24-hour urine collection period were described by the subjects and analyzed by a dietician. Simple regression analysis showed that plasma uridine was correlated with the urinary excretions of urea (R = 0.41, P urea. These results suggest that an increase in de novo pyrimidine synthesis leads to an increased concentration of uridine in plasma via nitrogen catabolism in healthy subjects with normouricemia and normal blood pressure. (c) 2010 Elsevier Inc. All rights reserved.

Equipment for collecting samples of radioactive solutions; Installation de prelevements d'echantillons de solutions radioactives

Energy Technology Data Exchange (ETDEWEB)

Raggenbass, A.; Fradin, J.; Joubert, G.

1958-12-03

The authors present an equipment aimed at collecting samples of fission products to perform radio-chemical analysis. As the sample must have a total activity between 1 and 50 micro-Curie, this installation comprises a sampling system and a dilution device which aims at bringing the sample to the suitable activity. Samples are collected by means of needles. The sample reproducibility is discussed. The dilution device is described.

Serum/plasma methylmercury determination by isotope dilution gas chromatography-inductively coupled plasma mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Baxter, Douglas C., E-mail: douglas.baxter@alsglobal.com [ALS Scandinavia AB, Aurorum 10, 977 75 Lulea (Sweden); Faarinen, Mikko [ALS Scandinavia AB, Aurorum 10, 977 75 Lulea (Sweden); Osterlund, Helene; Rodushkin, Ilia [ALS Scandinavia AB, Aurorum 10, 977 75 Lulea (Sweden); Division of Geosciences, Lulea University of Technology, 977 87 Lulea (Sweden); Christensen, Morten [ALS Scandinavia AB, Maskinvaegen 2, 183 53 Taeby (Sweden)

2011-09-09

Highlights: {center_dot} We determine methylmercury in serum and plasma using isotope dilution calibration. {center_dot} Separation by gas chromatography and detection by inductively coupled plasma mass spectrometry. {center_dot} Data for 50 specimens provides first reference range for methylmercury in serum. {center_dot} Serum samples shown to be stable for 11 months in refrigerator. - Abstract: A method for the determination of methylmercury in plasma and serum samples was developed. The method uses isotope dilution with {sup 198}Hg-labeled methylmercury, extraction into dichloromethane, back-extraction into water, aqueous-phase ethylation, purge and trap collection, thermal desorption, separation by gas chromatography, and mercury isotope specific detection by inductively coupled plasma mass spectrometry. By spiking 2 mL sample with 1.2 ng tracer, measurements in a concentration interval of (0.007-2.9) {mu}g L{sup -1} could be performed with uncertainty amplification factors <2. A limit of quantification of 0.03 {mu}g L{sup -1} was estimated at 10 times the standard deviation of concentrations measured in preparation blanks. Within- and between-run relative standard deviations were <10% at added concentration levels of 0.14 {mu}g L{sup -1}, 0.35 {mu}g L{sup -1} and 2.8 {mu}g L{sup -1}, with recoveries in the range 82-110%. Application of the method to 50 plasma/serum samples yielded a median (mean; range) concentration of methylmercury of 0.081 (0.091; <0.03-0.19) {mu}g L{sup -1}. This is the first time methylmercury has been directly measured in this kind of specimen, and is therefore the first estimate of a reference range.

Determination of uranium isotopic composition and 236U content of soil samples and hot particles using inductively coupled plasma mass spectrometry.

Science.gov (United States)

Boulyga, S F; Becker, J S

2001-07-01

As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The 236U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. Nuclear track radiography was applied for the identification and extraction of hot radioactive particles from soil samples. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on double-focusing inductively coupled plasma mass spectrometry (DF-ICP-MS) with a MicroMist nebulizer and a direct injection high-efficiency nebulizer (DIHEN). The performance of the DF-ICP-MS with a quartz DIHEN and plasma shielded torch was studied. Overall detection efficiencies of 4 x 10(-4) and 10(-3) counts per atom were achieved for 238U in DF-ICP-QMS with the MicroMist nebulizer and DIHEN, respectively. The rate of formation of uranium hydride ions UH+/U+ was 1.2 x 10(-4) and 1.4 x 10(-4), respectively. The precision of short-term measurements of uranium isotopic ratios (n = 5) in 1 microg L(-1) NBS U-020 standard solution was 0.11% (238U/235U) and 1.4% (236U/238U) using a MicroMist nebulizer and 0.25% (235U/238U) and 1.9% (236U/P38U) using a DIHEN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the 236U/238U ratio ranged from 10(-5) to 10(-3). Results obtained with ICP-MS, alpha- and gamma-spectrometry showed differences in the migration properties of spent uranium, plutonium, and americium. The isotopic ratio of uranium was also measured in hot particles extracted from soil samples.

Determination of uranium isotopic composition and 236U content of soil samples and hot particles using inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Boulyga, S.F.; Becker, J.S.

2001-01-01

As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The 236 U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. Nuclear track radiography was applied for the identification and extraction of hot radioactive particles from soil samples. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on double-focusing inductively coupled plasma mass spectrometry (DF-ICP-MS) with a MicroMist nebulizer and a direct injection high-efficiency nebulizer (DIHEN). The performance of the DF-ICP-MS with a quartz DIHEN and plasma shielded torch was studied. Overall detection efficiencies of 4 x 10 -4 and 10 -3 counts per atom were achieved for 238 U in DF-ICP-QMS with the MicroMist nebulizer and DIHEN, respectively. The rate of formation of uranium hydride ions UH + /U + was 1.2 x 10 -4 and 1.4 x 10 -4 , respectively. The precision of short-term measurements of uranium isotopic ratios (n = 5) in 1 μg L -1 NBS U-020 standard solution was 0.11% ( 238 U/ 235 U) and 1.4% ( 236 U/ 238 U) using a MicroMist nebulizer and 0.25% ( 235 U/ 238 U) and 1.9% ( 236 U/ 238 U) using a DIHEN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the 236 U/ 238 U ratio ranged from 10 -5 to 10 -3 . Results obtained with ICP-MS, α- and γ-spectrometry showed differences in the migration properties of spent uranium, plutonium, and americium. The isotopic ratio of uranium was also measured in hot particles extracted from soil samples. (orig.)

PIXE Analysis of Aerosol and Soil Samples Collected in the Adirondack Mountains

Science.gov (United States)

Yoskowitz, Joshua; Ali, Salina; Nadareski, Benjamin; Labrake, Scott; Vineyard, Michael

2014-09-01

We have performed an elemental analysis of aerosol and soil samples collected at Piseco Lake in Upstate New York using proton induced X-ray emission spectroscopy (PIXE). This work is part of a systematic study of airborne pollution in the Adirondack Mountains. Of particular interest is the sulfur content that can contribute to acid rain, a well-documented problem in the Adirondacks. We used a nine-stage cascade impactor to collect the aerosol samples near Piseco Lake and distribute the particulate matter onto Kapton foils by particle size. The soil samples were also collected at Piseco Lake and pressed into cylindrical pellets for experimentation. PIXE analysis of the aerosol and soil samples were performed with 2.2-MeV proton beams from the 1.1-MV Pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. There are higher concentrations of sulfur at smaller particle sizes (0.25-1 μm), suggesting that it could be suspended in the air for days and originate from sources very far away. Other elements with significant concentrations peak at larger particle sizes (1-4 μm) and are found in the soil samples, suggesting that these elements could originate in the soil. The PIXE analysis will be described and the resulting data will be presented.

Advanced Curation Activities at NASA: Implications for Astrobiological Studies of Future Sample Collections

Science.gov (United States)

McCubbin, F. M.; Evans, C. A.; Fries, M. D.; Harrington, A. D.; Regberg, A. B.; Snead, C. J.; Zeigler, R. A.

2017-01-01

The Astromaterials Acquisition and Curation Office (henceforth referred to herein as NASA Curation Office) at NASA Johnson Space Center (JSC) is responsible for curating all of NASA's extraterrestrial samples. Under the governing document, NASA Policy Directive (NPD) 7100.10F JSC is charged with curation of all extraterrestrial material under NASA control, including future NASA missions. The Directive goes on to define Curation as including documentation, preservation, preparation, and distribution of samples for re-search, education, and public outreach. Here we briefly describe NASA's astromaterials collections and our ongoing efforts related to enhancing the utility of our current collections as well as our efforts to prepare for future sample return missions. We collectively refer to these efforts as advanced curation.

On the improvement of signal repeatability in laser-induced air plasmas

Science.gov (United States)

Zhang, Shuai; Sheta, Sahar; Hou, Zong-Yu; Wang, Zhe

2018-04-01

The relatively low repeatability of laser-induced breakdown spectroscopy (LIBS) severely hinders its wide commercialization. In the present work, we investigate the optimization of LIBS system for repeatability improvement for both signal generation (plasma evolution) and signal collection. Timeintegrated spectra and images were obtained under different laser energies and focal lengths to investigate the optimum configuration for stable plasmas and repeatable signals. Using our experimental setup, the optimum conditions were found to be a laser energy of 250 mJ and a focus length of 100 mm. A stable and homogeneous plasma with the largest hot core area in the optimum condition yielded the most stable LIBS signal. Time-resolved images showed that the rebounding processes through the air plasma evolution caused the relative standard deviation (RSD) to increase with laser energies of > 250 mJ. In addition, the emission collection was improved by using a concave spherical mirror. The line intensities doubled as their RSDs decreased by approximately 25%. When the signal generation and collection were optimized simultaneously, the pulse-to-pulse RSDs were reduced to approximately 3% for O(I), N(I), and H(I) lines, which are better than the RSDs reported for solid samples and showed great potential for LIBS quantitative analysis by gasifying the solid or liquid samples.

Multi-elemental analysis of aqueous geochemical samples by quadrupole inductively coupled plasma-mass spectrometry (ICP-MS)

Science.gov (United States)

Wolf, Ruth E.; Adams, Monique

2015-01-01

Typically, quadrupole inductively coupled plasma-mass spectrometry (ICP-MS) is used to determine as many as 57 major, minor, and trace elements in aqueous geochemical samples, including natural surface water and groundwater, acid mine drainage water, and extracts or leachates from geological samples. The sample solution is aspirated into the inductively coupled plasma (ICP) which is an electrodeless discharge of ionized argon gas at a temperature of approximately 6,000 degrees Celsius. The elements in the sample solution are subsequently volatilized, atomized, and ionized by the ICP. The ions generated are then focused and introduced into a quadrupole mass filter which only allows one mass to reach the detector at a given moment in time. As the settings of the mass analyzer change, subsequent masses are allowed to impact the detector. Although the typical quadrupole ICP-MS system is a sequential scanning instrument (determining each mass separately), the scan speed of modern instruments is on the order of several thousand masses per second. Consequently, typical total sample analysis times of 2–3 minutes are readily achievable for up to 57 elements.

Chromium-51-EDTA clearance in adults with a single-plasma sample.

Science.gov (United States)

Mårtensson, J; Groth, S; Rehling, M; Gref, M

1998-12-01

In 1996, a committee on renal clearance recommended a mean sojourn time-based methodology for single-sample determination of plasma clearance of 99mTc-diethylenetriamine pentaacetic acid (DTPA) to be used on adults if the patient's glomerular filtration rate (GFR) is suspected to be >30 ml/min. The main purpose of this study was to derive a mean sojourn time-based formula for calculation of 51Cr-ethylenediamine tetraacetic acid (EDTA) clearance in adults. Two groups of patients with 51Cr-EDTA clearance (Cl) between 16 and 172 ml/min were studied. In Group I (n = 46), reference Cl was determined as a multiplasma sample, single-injection method (ClSM). Sixteen blood samples were drawn from 0 until 5 hr after a single intravenous injection of 51Cr-EDTA. In Group II (n = 1046), reference Cl was determined by the Brøchner-Mortensen four-sample clearance method (ClBM). The plasma time-activity curves of Group I were used to derive two mean sojourn time-based formulas (Formulas 1 and 2) for calculation of a single-sample clearance. Formula 1 was derived from the entire time-activity curve, whereas the derivation of Formula 2 used only the final slope of the time-activity curve. The accuracy of the two formulas and the Christensen and Groth 99mTc-DTPA formula was tested on Group II. Chromium-51-EDTA Cl calculated by Formula 1 was almost identical to the Cl calculated by the reference Cl method (r = 0.982; SDdiff = 5.82 ml/min). Both 51Cr-EDTA Cl calculated by Formula 2 and by the 99mTc-DTPA formula showed close correlation with the reference method (r = 0.976, r = 0.985, respectively) but systematically overestimated GFR for the whole range of clearance values by 3.5 and 3.2 ml/min (ptime methodology. The determination is marginally more accurate (ptime-activity curve than from only the final slope. The single-sample formula derived for determination of 99mTc-DTPA Cl tends slightly to overestimate GFR if used to calculate 51Cr-EDTA Cl.

Study of aerosol sample interaction with dc plasma in the presence of oscillating magnetic field

International Nuclear Information System (INIS)

Stoiljkovic, M.M.; Pavlovic, M.S.; Savovic, J.; Kuzmanovic, M.; Marinkovic, M.

2005-01-01

Oscillating magnetic field was used to study the efficiency of the aerosol sample introduction into the dc plasma. At atmospheric plasmas, the effect of magnetic field is reduced to Lorentz forces on the current carrying plasma, which produces motion of the plasma. The motion velocity of dc plasma caused by oscillating magnetic field was correlated to spectral emission enhancement of analytes introduced as aerosols. Emission enhancement is the consequence of the reduced barrier to introduction of analyte species and aerosol particles into the hot plasma region. Two hypotheses described in the literature for the origin of the barrier are considered: (i) barrier induced by temperature field is based upon the thermophoretic forces on the aerosol particles when their radius is comparable to the molecular free path in the surrounding gas and (ii) barrier induced by radial electric field, recently described, that originates from gradients of charged particles in radial direction. Correlation between ionization energy of the analyte atoms with experimental emission enhancement obtained by the use of oscillating magnetic field indicates that mechanism (ii) based upon the radial electric field is predominant. The ultimate emission enhancement and possible analytical advantage is discussed

77 FR 38323 - Proposed Extension of Existing Information Collection; Respirable Coal Mine Dust Sampling

Science.gov (United States)

2012-06-27

... Information Collection; Respirable Coal Mine Dust Sampling AGENCY: Mine Safety and Health Administration... Sampling'' to more accurately reflect the type of information that is collected. Chronic exposure to... dust levels since 1970 and, consequently, the prevalence rate of black lung among coal miners, severe...

Elemental analysis of bead samples using a laser-induced plasma at low pressure

International Nuclear Information System (INIS)

Lie, Tjung Jie; Kurniawan, Koo Hendrik; Kurniawan, Davy P.; Pardede, Marincan; Suliyanti, Maria Margaretha; Khumaeni, Ali; Natiq, Shouny A.; Abdulmadjid, Syahrun Nur; Lee, Yong Inn; Kagawa, Kiichiro; Idris, Nasrullah; Tjia, May On

2006-01-01

An Nd:YAG laser (1064 nm, 8 ns, 30 mJ) was focused on various types of fresh, fossilized white coral and giant shell samples, including samples of imitation shell and marble. Such samples are extremely important as material for preparing prayer beads that are extensively used in the Buddhist faith. The aim of this research was to develop a non-destructive method to distinguish original beads from their imitations by means of spectral measurements of the carbon, hydrogen, sodium and magnesium emission intensities and by measuring the hardness of the sample using the ratio between Ca (II) 396.8 nm and Ca (I) 422.6 nm. Based on these measurements, original fresh coral beads can be distinguished from any imitation made from hard wood. The same technique was also effective in distinguishing beads made of shell from its imitation. A spectral analysis of bead was also performed on a fossilized white coral sample and the result can be used to distinguish to some extent the fossilized white coral beads from any imitation made from marble. It was also found that the plasma plume should be generated at low ambient pressure to significantly improve the hydrogen and carbon emission intensity and also to avoid energy loss inside the crater during laser irradiation at atmospheric pressure. The results of this study confirm that operating the laser-induced plasma spectroscopy at reduced ambient pressure offers distinct advantage for bead analysis over the conventional laser-induced breakdown spectroscopy (LIBS) technique operated at atmospheric pressure

Elemental analysis of bead samples using a laser-induced plasma at low pressure

Energy Technology Data Exchange (ETDEWEB)

Lie, Tjung Jie [Research Center of Maju Makmur Mandiri Foundation, 40 Srengseng Raya, Kembangan, Jakarta Barat 11630 (Indonesia); Kurniawan, Koo Hendrik [Research Center of Maju Makmur Mandiri Foundation, 40 Srengseng Raya, Kembangan, Jakarta Barat 11630 (Indonesia)]. E-mail: kurnia18@cbn.net.id; Kurniawan, Davy P. [Research Center of Maju Makmur Mandiri Foundation, 40 Srengseng Raya, Kembangan, Jakarta Barat 11630 (Indonesia); Pardede, Marincan [Research Center of Maju Makmur Mandiri Foundation, 40 Srengseng Raya, Kembangan, Jakarta Barat 11630 (Indonesia); Suliyanti, Maria Margaretha [Graduate Program in Opto Electrotechniques and Laser Applications, Faculty of Engineering, The University of Indonesia, 4 Salemba Raya, Jakarta 10430 (Indonesia); Khumaeni, Ali [Department of Physics, Faculty of Mathematics and Natural Sciences, Diponegoro University, Tembalang Campus, Semarang 50275 (Indonesia); Natiq, Shouny A. [Department of Physics, Faculty of Mathematics and Natural Sciences, Diponegoro University, Tembalang Campus, Semarang 50275 (Indonesia); Abdulmadjid, Syahrun Nur [Department of Physics, Faculty of Mathematics and Natural Sciences, Syiah Kuala University, Darussalam, Banda Aceh 23116 (Indonesia); Lee, Yong Inn [Physics Department, Chonbuk National University, Chonju 561-756, South Korea (Korea); Kagawa, Kiichiro [Department of Physics, Faculty of Education and Regional Studies, Fukui University, 9-1 bunkyo 3-chome, Fukui 910-8507 (Japan); Idris, Nasrullah [Department of Physics, Faculty of Education and Regional Studies, Fukui University, 9-1 bunkyo 3-chome, Fukui 910-8507 (Japan); Tjia, May On [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, 10 Ganesha, Bandung 40132 (Indonesia)

2006-01-15

An Nd:YAG laser (1064 nm, 8 ns, 30 mJ) was focused on various types of fresh, fossilized white coral and giant shell samples, including samples of imitation shell and marble. Such samples are extremely important as material for preparing prayer beads that are extensively used in the Buddhist faith. The aim of this research was to develop a non-destructive method to distinguish original beads from their imitations by means of spectral measurements of the carbon, hydrogen, sodium and magnesium emission intensities and by measuring the hardness of the sample using the ratio between Ca (II) 396.8 nm and Ca (I) 422.6 nm. Based on these measurements, original fresh coral beads can be distinguished from any imitation made from hard wood. The same technique was also effective in distinguishing beads made of shell from its imitation. A spectral analysis of bead was also performed on a fossilized white coral sample and the result can be used to distinguish to some extent the fossilized white coral beads from any imitation made from marble. It was also found that the plasma plume should be generated at low ambient pressure to significantly improve the hydrogen and carbon emission intensity and also to avoid energy loss inside the crater during laser irradiation at atmospheric pressure. The results of this study confirm that operating the laser-induced plasma spectroscopy at reduced ambient pressure offers distinct advantage for bead analysis over the conventional laser-induced breakdown spectroscopy (LIBS) technique operated at atmospheric pressure.

Acceptability of self-collected vaginal samples for HPV testing in an ...

African Journals Online (AJOL)

Objective: To evaluate the acceptability of self-collected vaginal samples for HPV testing in women living in rural and urban areas of ... Conclusion: Acceptability of self-sampling for HPV testing was similarly excellent in both groups despite their difference in terms ... cancer is the leading cause of death caused by cancer in.

Comparison of Three Sample Preparation Procedures for the Quantification of L-Arginine, Asymmetric Dimethylarginine, and Symmetric Dimethylarginine in Human Plasma Using HPLC-FLD

DEFF Research Database (Denmark)

Schou-Pedersen, Anne Marie Voigt; Lykkesfeldt, Jens

2018-01-01

Increased asymmetric dimethylarginine (ADMA) in human plasma has been associated with reduced generation of nitric oxide, leading to atherosclerotic diseases. ADMA may therefore be an important biomarker for cardiovascular disease. In the present study, three sample preparation techniques were co...... sample preparation of human plasma samples before HPLC-FLD in providing important information regarding elevated ADMA concentrations.......Increased asymmetric dimethylarginine (ADMA) in human plasma has been associated with reduced generation of nitric oxide, leading to atherosclerotic diseases. ADMA may therefore be an important biomarker for cardiovascular disease. In the present study, three sample preparation techniques were...... compared regarding the quantification of L-arginine and ADMA in human plasma: (A) protein precipitation (PP) based on aqueous trichloroacetic acid (TCA), (B) PP using a mixture of ammonia and acetonitrile, and (C) solid-phase extraction (SPE). The samples were analysed by using high-performance liquid...

Analysis of multiple single nucleotide polymorphisms (SNP) on DNA traces from plasma and dried blood samples

NARCIS (Netherlands)

Catsburg, Arnold; van der Zwet, Wil C.; Morre, Servaas A.; Ouburg, Sander; Vandenbroucke-Grauls, Christina M. J. E.; Savelkoul, Paul H. M.

2007-01-01

Reliable analysis of single nucleotide polymorphisms (SNPs) in DNA derived from samples containing low numbers of cells or from suboptimal sources can be difficult. A new procedure to characterize multiple SNPs in traces of DNA from plasma and old dried blood samples was developed. Six SNPs in the

Two-compartment, two-sample technique for accurate estimation of effective renal plasma flow: Theoretical development and comparison with other methods

International Nuclear Information System (INIS)

Lear, J.L.; Feyerabend, A.; Gregory, C.

1989-01-01

Discordance between effective renal plasma flow (ERPF) measurements from radionuclide techniques that use single versus multiple plasma samples was investigated. In particular, the authors determined whether effects of variations in distribution volume (Vd) of iodine-131 iodohippurate on measurement of ERPF could be ignored, an assumption implicit in the single-sample technique. The influence of Vd on ERPF was found to be significant, a factor indicating an important and previously unappreciated source of error in the single-sample technique. Therefore, a new two-compartment, two-plasma-sample technique was developed on the basis of the observations that while variations in Vd occur from patient to patient, the relationship between intravascular and extravascular components of Vd and the rate of iodohippurate exchange between the components are stable throughout a wide range of physiologic and pathologic conditions. The new technique was applied in a series of 30 studies in 19 patients. Results were compared with those achieved with the reference, single-sample, and slope-intercept techniques. The new two-compartment, two-sample technique yielded estimates of ERPF that more closely agreed with the reference multiple-sample method than either the single-sample or slope-intercept techniques

An attempt to validate serum and plasma as sample matrices for analyses of polychlorobiphenylols

Energy Technology Data Exchange (ETDEWEB)

Weiss, J.; Bergman, Aa. [Stockholm Univ. (Sweden). Dept. of Environmental Chemistry; Bignert, A. [Museum of Natural History (Sweden)

2004-09-15

Polychlorinated biphenyls (PCBs) form hydroxylated metabolites (OH-PCBs), as reported both from wildlife and from experimental animal studies already in the early 1970s'. However, the interest increased in OH-PCBs from the mid 1990s' depending on the discovery that some OHPCB congeners are strongly retained in the blood of birds, fish and mammals, including humans. The interest is linked to the fact that OH-PCBs is strongly, but reversibly, bound to the blood protein transthyretin (TTR). It is reasonable to believe that the strong TTR binding may have toxicological impact, probably related to endocrine type effects. Importantly, OH-PCBs are present in blood at far higher concentrations than in any other compartment in the body, which is dependent on the physico-chemical characteristics of the phenols. Analyses of OH-PCBs have thus been concentrated to whole blood, plasma or serum. Still there is no comparison between the three sample types even though it is clear that whole blood is not optimal due to the large proportion of haemoglobin in the sample that make the clean up more difficult than if plasma or serum is selected for analysis. In the present study we have addressed two questions: First we have looked at any potential differences in the analytical results of OH-PCBs when using serum and plasma for extraction and clean up; Second, the serum and plasma applied in the validation has been unfrozen, frozen (at -20 C) for two months and frozen for twenty months, respectively.

Portable Automation of Static Chamber Sample Collection for Quantifying Soil Gas Flux

Energy Technology Data Exchange (ETDEWEB)

Davis, Morgan P.; Groh, Tyler A.; Parkin, Timothy B.; Williams, Ryan J.; Isenhart, Thomas M.; Hofmockel, Kirsten S.

2018-01-01

Quantification of soil gas flux using the static chamber method is labor intensive. The number of chambers that can be sampled is limited by the spacing between chambers and the availability of trained research technicians. An automated system for collecting gas samples from chambers in the field would eliminate the need for personnel to return to the chamber during a flux measurement period and would allow a single technician to sample multiple chambers simultaneously. This study describes Chamber Automated Sampling Equipment (FluxCASE) to collect and store chamber headspace gas samples at assigned time points for the measurement of soil gas flux. The FluxCASE design and operation is described, and the accuracy and precision of the FluxCASE system is evaluated. In laboratory measurements of nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) concentrations of a standardized gas mixture, coefficients of variation associated with automated and manual sample collection were comparable, indicating no loss of precision. In the field, soil gas fluxes measured from FluxCASEs were in agreement with manual sampling for both N2O and CO2. Slopes of regression equations were 1.01 for CO2 and 0.97 for N2O. The 95% confidence limits of the slopes of the regression lines included the value of one, indicating no bias. Additionally, an expense analysis found a cost recovery ranging from 0.6 to 2.2 yr. Implementing the FluxCASE system is an alternative to improve the efficiency of the static chamber method for measuring soil gas flux while maintaining the accuracy and precision of manual sampling.

Trace Elements Analysis of Archeological Brick Samples Collected from Different Historical Placs in Rajshahi Division

International Nuclear Information System (INIS)

Begum, Bilkis A.; Biswas, Shapan K.; Matin, Mohammed A.; Hoque, Mohammed M.; Hopke, Philip K.

2007-01-01

Twenty-nine brick samples were collected from different temples and palaces, namely Paharpur, Kumarpur, Gaurbari, Puthia and Natore in Rajshahi Division in Bangladesh. The samples were analyzed by X-ray Fluorescence (XRF) method. The elemental data sets have been analyzed in order to find out the general characteristics and any significant differences among the collected samples and identify the origin of these brick samples. Most of the crustal elements have enrichment factor (EF) values close to unity. Only Cu and Pb have high values that may come from painting as these have been collected from temples and palaces.(author)

A comparison of human papillomavirus testing of clinician-collected and self-collected samples during follow-up after screen-and-treat.

Science.gov (United States)

Taylor, Sylvia; Wang, Chunhui; Wright, Thomas C; Denny, Lynette; Kuhn, Louise

2011-08-15

Screen-and-treat cervical cancer prevention programs based on high-risk human papillomavirus (HPV) testing and cryotherapy have been shown to be effective in resource-limited settings. However, because cryotherapy is not 100% effective, follow-up is needed after treatment to detect post-treatment failures. We compared the test performances of high-risk HPV testing (Hybrid Capture 2) using self-collected and clinician-collected samples as well as cervical cytology for identifying cervical intraepithelial neoplasia grades 2 or 3 or invasive cervical cancer (CIN2+) among women who did (n=812) and did not (n=1858) undergo cryotherapy in a South African screen-and-treat trial. At 6 months after enrolment (and after cryotherapy, if performed), women were tested using all three screening methods and then underwent colposcopy/biopsy. A predefined subset of women (n=1,455) had extended follow-up with colposcopy/biopsy at 12 months. A total of 33 and 91 cases of CIN2+ were detected among treated and untreated women, respectively. The sensitivity of HPV testing using clinician-collected samples and cervical cytology did not differ by treatment status. HPV testing of clinician-collected samples detected the most cases of CIN2+ among both treated (85%) and untreated (91%) women (p=0.31). Cytology (at a cutoff of atypical squamous cells of undetermined significance or greater) detected 76% of cases among both treated and untreated women. However, the sensitivity of HPV testing using self-collected samples was significantly lower among treated versus untreated women (55% vs. 78%, p=0.01). HPV testing using self-collected vaginal specimens may be useful in primary screening but performs poorly for detecting post-treatment failures. Copyright © 2010 UICC.

Methods for collecting algal samples as part of the National Water-Quality Assessment Program

Science.gov (United States)

Porter, Stephen D.; Cuffney, Thomas F.; Gurtz, Martin E.; Meador, Michael R.

1993-01-01

Benthic algae (periphyton) and phytoplankton communities are characterized in the U.S. Geological Survey's National Water-Quality Assessment Program as part of an integrated physical, chemical, and biological assessment of the Nation's water quality. This multidisciplinary approach provides multiple lines of evidence for evaluating water-quality status and trends, and for refining an understanding of the factors that affect water-quality conditions locally, regionally, and nationally. Water quality can be characterized by evaluating the results of qualitative and quantitative measurements of the algal community. Qualitative periphyton samples are collected to develop of list of taxa present in the sampling reach. Quantitative periphyton samples are collected to measure algal community structure within selected habitats. These samples of benthic algal communities are collected from natural substrates, using the sampling methods that are most appropriate for the habitat conditions. Phytoplankton samples may be collected in large nonwadeable streams and rivers to meet specific program objectives. Estimates of algal biomass (chlorophyll content and ash-free dry mass) also are optional measures that may be useful for interpreting water-quality conditions. A nationally consistent approach provides guidance on site, reach, and habitat selection, as well as information on methods and equipment for qualitative and quantitative sampling. Appropriate quality-assurance and quality-control guidelines are used to maximize the ability to analyze data locally, regionally, and nationally.

Simultaneous PIXE and PIGE analyses of aerosol samples collected in urban areas

International Nuclear Information System (INIS)

Boni, C.; Caruso, E.; Cereda, E.; Marcazzan, G.M.; Redaelli, P.; Bacci, P.

1988-01-01

The paper concerns the simultaneous PIXE (Particle Induced X-ray Emission) and PIGE (Proton Induced Gamma-ray Emission) analyses of aerosol samples collected in urban areas. The results show that PIGE can detect Li, F, Na, Al, and Si in fly ashes and F, Na, Al and Si in atmospheric aerosol. The PIXE-PIGE technique has also been applied to 80 samples of atmospheric particular matter collected above Milan during the winter and summer months of 1986/7, and the average values of concentrations and enrichment factors are given for the detected elements. (U.K.)

Assembly for collecting samples for purposes of identification or analysis and method of use

Science.gov (United States)

Thompson, Cyril V [Knoxville, TN; Smith, Rob R [Knoxville, TN

2010-02-02

An assembly and an associated method for collecting a sample of material desired to be characterized with diagnostic equipment includes or utilizes an elongated member having a proximal end with which the assembly is manipulated by a user and a distal end. In addition, a collection tip which is capable of being placed into contact with the material to be characterized is supported upon the distal end. The collection tip includes a body of chemically-inert porous material for binding a sample of material when the tip is placed into contact with the material and thereby holds the sample of material for subsequent introduction to the diagnostic equipment.

Comparative multielement analyses of airborne particulate samples collected in various areas

International Nuclear Information System (INIS)

Mamuro, Tetsuo; Matsuda, Yatsuka; Mizohata, Akira

1973-01-01

In order to grasp the characteristic features of the air pollution by particulates in various areas in Japan, multielement analyses by instrumental neutron activation analysis and radioisotope energy dispersive X-ray fluorescence analysis were applied to 31 airborne particulate samples collected in 15 different areas, and the analytical results obtained were compared with one another. All the samples were collected by so-called ''10 micron cut'' samplers, the collection efficiency of which is considered to be 50% at 8μ and nearly zero beyond 10μ. Among the areas in question there are clean seaside areas, heavily industrialized areas, small cities along the Inland Sea or the Pacific Ocean around which industrialization is progressing, a small city having only a big iron work, an area famous for its ceramic industry and so on. The atmospheres over them were found to be quite different not only in pollution extent but also in pollution pattern. (auth.)

Tritium retention on the surface of stainless steel samples fixed on the plasma-facing wall in LHD

International Nuclear Information System (INIS)

Matsuyama, Masao; Abe, Shinsuke; Nishimura, Kiyohiko; Ashikawa, Naoko; Sagara, Akio; Oya, Yasuhisa; Okuno, Kenji; Yamauchi, Yuji; Nobuta, Yuji

2014-01-01

Effects of pre-heating for retention and distribution of tritium have been studied using samples fixed on the wall of the Large Helical Device during a plasma campaign. The samples were fixed at four different locations. The plasma-facing surface of the samples was covered with deposition layers of different thickness in each sample. Retention behavior in deposition layers was observed using β-ray-induced X-ray spectrometry and imaging plate technique. Pre-heating of the samples in vacuum was changed in a temperature range from 300 to 623 K, and subsequent tritium exposure was carried out at 300 K in every runs. Non-uniformity of tritium distribution clearly appeared even in the as-received samples which was not pre-heated. It is considered, therefore, that non-uniform adsorption sites of tritium have been produced during a formation process of deposition layers. In addition, it was seen that the amount of tritium retention increased with an increase in the pre-heating temperature, indicating that adsorption sites of tritium were newly formed in the deposition layers by heating in vacuum. (author)

Measurements of plasma temperature and electron density in laser ...

Indian Academy of Sciences (India)

of 6 ns focussed onto a copper solid sample in air at atmospheric pressure is studied spectroscopically. ... Pulsed laser-induced plasmas (LIPs) of metals and alloys formed at laser pulse ir- radiances near the .... fibre-based collection system.

Analytical sample preparation strategies for the determination of antimalarial drugs in human whole blood, plasma and urine

DEFF Research Database (Denmark)

Casas, Monica Escolà; Hansen, Martin; Krogh, Kristine A

2014-01-01

the available sample preparation strategies combined with liquid chromatographic (LC) analysis to determine antimalarials in whole blood, plasma and urine published over the last decade. Sample preparation can be done by protein precipitation, solid-phase extraction, liquid-liquid extraction or dilution. After...

Isotope ratio measurements with multiple collection inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Platzner, I.T.; Segal, I.; Halicz, L.

2003-01-01

In the studies summarized in this review, it has been shown that IRM of lead in silicates can be carried out without lead separation and purification. Because of time independent mass discrimination and lack of chemical interaction at high plasma temperatures, simple interference corrections are feasible. This data further support the observation that MC-ICP-MS provides data with superior precision comparing to TIMS. Furthermore, it should be noted that the multi collection instrumental configuration exhibits the capability to perform a single IRM with excellent precision and high accuracy for elements with a large number of isotopes. Four of the discussed elements have six (Er) and seven (Dy, Yb, Os) isotopes

Slide-away distributions and relevant collective modes in high-temperature plasmas

International Nuclear Information System (INIS)

Coppi, B.; Pegoraro, F.; Pozzoli, R.; Rewoldt, G.

1976-01-01

The evolution of the electron distribution function, when an electric field that is not too small in comparison with the critical electron runaway field is applied along the confining magnetic field of a high temperature plasma, is analysed. In the regimes considered, a finite fraction of the electron population has magnetically trapped orbits, and is not appreciably affected by the applied electric field, while the distribution of circulating electrons tends to ''slide away'' as a whole. Then the Spitzer-Haerm model for the current-carrying electron distribution is inadequate, and the role that collective modes, in particular current-driven microinstabilities, and collisions can play in producing a stationary electron distribution is analysed. Modes at the ion plasma frequency, ωsub(pi), that are driven by the positive slope of the current-carrying electron distribution, can be excited, when the average electron drift velocity is a finite fraction of the electron thermal velocity, and transfer transverse energy to the main body of the electron distribution. These features are consistent with the experimental observations performed on the Alcator device. Modes at the ''reduced'' electron plasma frequency (ksub(parallel)/k)ωsub(pe) can also be excited both in connection with the modes at wsub(pi) and independently. Modes at the electron gyrofrequency Ωsub(e) associated with the loss-cone feature that the electron distribution tends to develop are considered, among others, as a factor for the strongly enhanced electron cyclotron emission experimentally observed in regimes where non-thermal electron distributions have been realized. (author)

Feasibility of Using Convalescent Plasma Immunotherapy for MERS-CoV Infection, Saudi Arabia

Science.gov (United States)

Hajeer, Ali H.; Luke, Thomas; Raviprakash, Kanakatte; Balkhy, Hanan; Johani, Sameera; Al-Dawood, Abdulaziz; Al-Qahtani, Saad; Al-Omari, Awad; Al-Hameed, Fahad; Hayden, Frederick G.; Fowler, Robert; Bouchama, Abderrezak; Shindo, Nahoko; Al-Khairy, Khalid; Carson, Gail; Taha, Yusri; Sadat, Musharaf; Alahmadi, Mashail

2016-01-01

We explored the feasibility of collecting convalescent plasma for passive immunotherapy of Middle East respiratory syndrome coronavirus (MERS-CoV) infection by using ELISA to screen serum samples from 443 potential plasma donors: 196 patients with suspected or laboratory-confirmed MERS-CoV infection, 230 healthcare workers, and 17 household contacts exposed to MERS-CoV. ELISA-reactive samples were further tested by indirect fluorescent antibody and microneutralization assays. Of the 443 tested samples, 12 (2.7%) had a reactive ELISA result, and 9 of the 12 had reactive indirect fluorescent antibody and microneutralization assay titers. Undertaking clinical trials of convalescent plasma for passive immunotherapy of MERS-CoV infection may be feasible, but such trials would be challenging because of the small pool of potential donors with sufficiently high antibody titers. Alternative strategies to identify convalescent plasma donors with adequate antibody titers should be explored, including the sampling of serum from patients with more severe disease and sampling at earlier points during illness. PMID:27532807

Effect of hypergravity on catecholamine levels in telemetrically collected blood of rats during centrifugation

Science.gov (United States)

Kvetnansky, R.; Petrak, J.; Mravec, B.; Tillinger, A.; Jurani, M.; Baranovska, M.; Hapala, I.; Frollo, I.

2005-08-01

Hypergravity is known to activate the sympathoadrenal system (SAS). Rats subjected to various accelerations (+G) exhibited increased levels of plasma epinephrine (EPI) and partly also norepinephrine (NE). However, the collection of blood was performed after centrifugation finished and therefore plasma NE and EPI levels could have been affected by the process of deceleration. The aim of this study was to evaluate plasma EPI and NE levels in blood collected directly during the centrifugation after reaching different +G, using newly developed remote controlled equipment. Such telemetrically regulated equipment for multiple blood sampling allows us to investigate selective effects of hypergravity during centrifugation. All animals had a polyethylene tubing in the tail artery which was connected to a pre-programmed device for three blood withdrawals (0.6 ml each) into individual syringes, performed at any chosen time intervals. Plasma EPI and NE levels were measured at hypergravity between +1G - +5G. Plasma EPI levels showed a huge, hypergravity dependent increase at the interval of 10-20 min. After the blood collection was completed, the centrifuge was turned off and another blood sampling was performed immediately after the centrifuge stopped (10 min). In these samples plasma EPI levels showed a significant reduction compared to the 20 min interval of centrifugation but the EPI levels at 4G-6G were still significantly elevated compared to pre- centrifugation levels. Plasma NE levels showed less pronounced changes (increased after 6G only) with a slower return to control levels.Thus, our data has shown completely different responses of the adrenomedullary (epinephrine) and sympathoneural (norepinephrine) systems to hypergravitation. This data shows that the increased gravitation and not the stressful situations connected with centrifugation is the factor responsible for massive activation of the adrenomedullary system. The mechanism of small activation of the

Characteristics of the samples in the FNG fission deposit collection

Energy Technology Data Exchange (ETDEWEB)

Meadows, J.W.

1990-12-01

Information concerning the samples in the Fast Neutron Generator (FNG) Group's fission deposit collection has been assembled. This includes the physical dimensions, isotopic analyses, half-lives, alpha emission rates specific activities and deposit weights. 10 refs., 9 figs., 5 tabs.

Some remarks on stochastic collective oscillations in ECRIS plasmas

International Nuclear Information System (INIS)

Golovanivsky, K.S.

1993-08-01

It is proposed that the thermal fluctuations in plasmas in general and in ECRIS plasmas in particular create rather strong stochastic electrical fields affecting both confinement and heating of an ECRIS plasma. The amplitude, range and characteristic frequency of the stochastic fields as well as the perpendicular diffusion coefficient and the upper density limit for the mirror confinement are determined on the level of the approximate evaluations. Some aspects of the ECRIS plasma's peculiarities due to the stochastic electrical fields are discussed. (author) 7 refs., 5 figs

A comparison of results for samples collected with bailers constructed of different materials

International Nuclear Information System (INIS)

Thomey, N.; Ogle, R.; Jackson, J.

1992-01-01

A bailer is one of the most common sampling devices used to collect ground water samples. Bailers constructed from various materials are available; teflon, polyvinyl chloride (PVC), polyethylene, and stainless steel are all commonly used. It is widely recognized that sample results can be affected by the material from which the bailer is constructed. Teflon and stainless steel are usually recommended based upon their inert properties. The cost of these bailers is significantly higher than other types. For the purposes of petroleum storage tank investigations, sampling devices that would not compromise sample quality but be more economical than teflon or stainless steel would be especially desirable. Water samples were collected using the different types of bailers; teflon, stainless steel, PVC, and polyethylene. Split samples were analyzed for benzene, toluene, ethylbenzene, total xylenes, and Total Petroleum Hydrocarbons. The analytical results were compared to determine if differences were due to normal analytical variances or due to interaction of the sample with the sampling device. No difference was noted in the results which were obtained

Application of bar codes to the automation of analytical sample data collection

International Nuclear Information System (INIS)

Jurgensen, H.A.

1986-01-01

The Health Protection Department at the Savannah River Plant collects 500 urine samples per day for tritium analyses. Prior to automation, all sample information was compiled manually. Bar code technology was chosen for automating this program because it provides a more accurate, efficient, and inexpensive method for data entry. The system has three major functions: sample labeling is accomplished at remote bar code label stations composed of an Intermec 8220 (Intermec Corp.) interfaced to an IBM-PC, data collection is done on a central VAX 11/730 (Digital Equipment Corp.). Bar code readers are used to log-in samples to be analyzed on liquid scintillation counters. The VAX 11/730 processes the data and generates reports, data storage is on the VAX 11/730 and backed up on the plant's central computer. A brief description of several other bar code applications at the Savannah River Plant is also presented

Nonlineart theory of relativistic beam-plasma instabilities in the regime of the collective Cherenkov effect

Energy Technology Data Exchange (ETDEWEB)

Bobylev, Yu. V. [L.N. Tolstoy Tula State Pedagogical University (Russian Federation); Kuzelev, M. V. [Moscow State University (Russian Federation); Rukhadze, A. A. [Russian Academy of Sciences, Prokhorov Institute of General Physics (Russian Federation)

2008-02-15

A general mathematical model is proposed that is based on the Vlasov kinetic equation with a self-consistent field and describes the nonlinear dynamics of the electromagnetic instabilities of a relativistic electron beam in a spatially bounded plasma. Two limiting cases are analyzed, namely, high-frequency (HF) and low-frequency (LF) instabilities of a relativistic electron beam, of which the LF instability is a qualitatively new phenomenon in comparison with the known Cherenkov resonance effects. For instabilities in the regime of the collective Cherenkov effect, the equations containing cubic nonlinearities and describing the nonlinear saturation of the instabilities of a relativistic beam in a plasma are derived by using the methods of expansion in small perturbations of the trajectories and momenta of the beam electrons. Analytic expressions for the amplitudes of the interacting beam and plasma waves are obtained. The analytical results are shown to agree well with the exact solutions obtained numerically from the basic general mathematical model of the instabilities in question. The general mathematical model is also used to discuss the effects associated with variation in the constant component of the electron current in a beam-plasma system.

Sample collection: an overview of the Hydrogeochemical and Stream Sediment Reconnaissance Program

International Nuclear Information System (INIS)

Bolivar, S.L.

1979-01-01

A Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) for uranium is currently being conducted throughout the conterminous United States and Alaska. The HSSR is part of the National Uranium Resource Evaluation sponsored by the US Department of Energy. This ambitious geochemical reconnaissance program is conducted by four national laboratories: Los Alamos Scientific Laboratory, Lawrence Livermore Laboratory, Oak Ridge Gaseous Diffusion Plant, and Savannah River Laboratory. The program is based on an extensive review of world literature, reconnaissance work done in other countries, and pilot studies conducted by each laboratory. Sample-collection methods and sample density are determined to optimize the probability of detecting potential uranium mineralization. To achieve this aim, each laboratory has developed independent standardized field collection procedures that are designed for its section of the country. Field parameters such as pH, conductivity, climate, geography, and geology are recorded at each site. Most samples are collected at densities of one sample site per 10 to 23 km 2 . The HSSR program has helped to improve existing hydrogeochemical reconnaissance exploration techniques. In addition to providing industry with data that may help to identify potential uranium districts and to extend known uranium provinces, the HSSR also provides multi-element analytical data, which can be used in water quality, soil, sediment, environmental, and base-metal exploration studies

An evaluation of saliva as an alternative to plasma for the detection of hepatitis C virus antibodies

Directory of Open Access Journals (Sweden)

Moorthy M

2008-01-01

Full Text Available Purpose: Seroepidemiological studies on the prevalence of Hepatitis C virus (HCV in India have been hampered by reluctance of subjects to provide blood samples for testing. We evaluated the use of saliva as an alternate specimen to blood for the detection of antibodies to HCV. Methods: Chronic liver disease (CLD patients attending the liver clinic were recruited for this study. A saliva and plasma sample (sample pair was collected from each patient included in the study. Saliva samples were collected using a commercially available collection device - OmniSal. Sample pairs were tested with an in-use ELISA for the detection of antibodies to HCV (HCV-Ab, with a minor modification in the manufacturer′s protocol while testing saliva. The cut-off absorbance value for declaring a sample as positive was determined by receiver operating curve (ROC analysis. HCV-Ab positivity in saliva was compared with that in plasma as well as with viral load in plasma and infecting genotype of the virus. Sensitivity, specificity, positive and negative predictive values, and correlation coefficients were calculated using Medcalc statistical software. Results: The optimal accuracy indices were: sensitivity-81.6%; specificity-92.5%; PPV-85.1% and NPV-90.5%. No correlation was found between salivary positivity and HCV viral load in plasma or infecting genotype. Conclusions: The accuracy indices indicate that the assay must be optimized further before it can be recommended for routine use in epidemiological surveys for HCV-Ab.

The Importance of Meteorite Collections to Sample Return Missions: Past, Present, and Future Considerations

Science.gov (United States)

Welzenbach, L. C.; McCoy, T. J.; Glavin, D. P.; Dworkin, J. P.; Abell, P. A.

2012-01-01

While much of the scientific community s current attention is drawn to sample return missions, it is the existing meteorite and cosmic dust collections that both provide the paradigms to be tested by these missions and the context for interpreting the results. Recent sample returns from the Stardust and Hayabusa missions provided us with new materials and insights about our Solar System history and processes. As an example, Stardust sampled CAIs among the population of cometary grains, requiring extensive and unexpected radial mixing in the early solar nebula. This finding would not have been possible, however, without extensive studies of meteoritic CAIs that established their high-temperature, inner Solar System formation. Samples returned by Stardust also revealed the first evidence of a cometary amino acid, a discovery that would not have been possible with current in situ flight instrument technology. The Hayabusa mission provided the final evidence linking ordinary chondrites and S asteroids, a hypothesis that developed from centuries of collection and laboratory and ground-based telescopic studies. In addition to these scientific findings, studies of existing meteorite collections have defined and refined the analytical techniques essential to studying returned samples. As an example, the fortuitous fall of the Allende CV3 and Murchison CM2 chondrites within months before the return of Apollo samples allowed testing of new state-of-the-art analytical facilities. The results of those studies not only prepared us to better study lunar materials, but unanticipated discoveries changed many of our concepts about the earliest history and processes of the solar nebula. This synergy between existing collections and future space exploration is certainly not limited to sample return missions. Laboratory studies confirmed the existence of meteorites from Mars and raised the provocative possibility of preservation of ancient microbial life. The laboratory studies in

Treatment failure of nelfinavir-containing triple therapy can largely be explained by low nelfinavir plasma concentrations

NARCIS (Netherlands)

Burger, David M.; Hugen, Patricia W. H.; Aarnoutse, Rob E.; Hoetelmans, Richard M. W.; Jambroes, Marielle; Nieuwkerk, Pythia T.; Schreij, Gerrit; Schneider, Margriet M. E.; van der Ende, Marchina E.; Lange, Joep M. A.

2003-01-01

The relationship between plasma concentrations of nelfinavir and virologic treatment failure was investigated to determine the minimum effective concentration of nelfinavir. Plasma samples were prospectively collected from treatment-naive patients who began taking nelfinavir, 1,250 mg BID + two

Collection and preparation of bottom sediment samples for analysis of radionuclides and trace elements

International Nuclear Information System (INIS)

2003-07-01

The publication is the first in a series of TECDOCs on sampling and sample handling as part of the IAEA support to improve reliability of nuclear analytical techniques (NATs) in Member State laboratories. The purpose of the document is to provide information on the methods for collecting sediments, the equipment used, and the sample preparation techniques for radionuclide and elemental analysis. The most appropriate procedures for defining the strategies and criteria for selecting sampling locations, for sample storage and transportation are also given. Elements of QA/QC and documentation needs for sampling and sediment analysis are discussed. Collection and preparation of stream and river bottom sediments, lake bottom sediments, estuary bottom sediments, and marine (shallow) bottom sediments are covered. The document is intended to be a comprehensive manual for the collection and preparation of bottom sediments as a prerequisite to obtain representative and meaningful results using NATs. Quality assurance and quality control (QA/QC) is emphasized as an important aspect to ensure proper collection, transportation, preservation, and analysis since it forms the basis for interpretation and legislation. Although there are many approaches and methods available for sediment analyses, the scope of the report is limited to sample preparation for (1) analysis of radionuclides (including sediment dating using radionuclides such as Pb-210 and Cs-137) and (2) analysis of trace, minor and major elements using nuclear and related analytical techniques such as NAA, XRF and PIXE

Collection and preparation of bottom sediment samples for analysis of radionuclides and trace elements

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

The publication is the first in a series of TECDOCs on sampling and sample handling as part of the IAEA support to improve reliability of nuclear analytical techniques (NATs) in Member State laboratories. The purpose of the document is to provide information on the methods for collecting sediments, the equipment used, and the sample preparation techniques for radionuclide and elemental analysis. The most appropriate procedures for defining the strategies and criteria for selecting sampling locations, for sample storage and transportation are also given. Elements of QA/QC and documentation needs for sampling and sediment analysis are discussed. Collection and preparation of stream and river bottom sediments, lake bottom sediments, estuary bottom sediments, and marine (shallow) bottom sediments are covered. The document is intended to be a comprehensive manual for the collection and preparation of bottom sediments as a prerequisite to obtain representative and meaningful results using NATs. Quality assurance and quality control (QA/QC) is emphasized as an important aspect to ensure proper collection, transportation, preservation, and analysis since it forms the basis for interpretation and legislation. Although there are many approaches and methods available for sediment analyses, the scope of the report is limited to sample preparation for (1) analysis of radionuclides (including sediment dating using radionuclides such as Pb-210 and Cs-137) and (2) analysis of trace, minor and major elements using nuclear and related analytical techniques such as NAA, XRF and PIXE.

Estimation of 131J-Jodohippurateclearance by a simplified method using a single plasma sample

International Nuclear Information System (INIS)

Botsch, H.; Golde, G.; Kampf, D.

1980-01-01

Theoretical volumes calculated from the reciprocal of the plasma concentration of 131 J-Jodohippurate were compared in 95 patients with clearance values calculated by the 2-compartment-method and in 18 patients with conventional PAH-clearance. For estimating Hippurate-clearance from a single blood sampling the most favorable time is 45 min. after injection (r = 0.96; clearance 400/ml/min.: r = 0.98). Clearance values may be derived from the formula: C = 0.4 + 7.26 V - 0.021 x V 2 (V = injected activity/activity per l plasma taken 45 min. after injection). The simplicity, precision and reproducibility of the above mentioned clearance-method is emphasized. (orig.) [de

Sources of variability in collection and preparation of paint and lead-coating samples.

Science.gov (United States)

Harper, S L; Gutknecht, W F

2001-06-01

Chronic exposure of children to lead (Pb) can result in permanent physiological impairment. Since surfaces coated with lead-containing paints and varnishes are potential sources of exposure, it is extremely important that reliable methods for sampling and analysis be available. The sources of variability in the collection and preparation of samples were investigated to improve the performance and comparability of methods and to ensure that data generated will be adequate for its intended use. Paint samples of varying sizes (areas and masses) were collected at different locations across a variety of surfaces including metal, plaster, concrete, and wood. A variety of grinding techniques were compared. Manual mortar and pestle grinding for at least 1.5 min and mechanized grinding techniques were found to generate similar homogenous particle size distributions required for aliquots as small as 0.10 g. When 342 samples were evaluated for sample weight loss during mortar and pestle grinding, 4% had 20% or greater loss with a high of 41%. Homogenization and sub-sampling steps were found to be the principal sources of variability related to the size of the sample collected. Analysis of samples from different locations on apparently identical surfaces were found to vary by more than a factor of two both in Pb concentration (mg cm-2 or %) and areal coating density (g cm-2). Analyses of substrates were performed to determine the Pb remaining after coating removal. Levels as high as 1% Pb were found in some substrate samples, corresponding to more than 35 mg cm-2 Pb. In conclusion, these sources of variability must be considered in development and/or application of any sampling and analysis methodologies.

Charging and heat collection by a positively charged dust grain in a plasma.

Science.gov (United States)

Delzanno, Gian Luca; Tang, Xian-Zhu

2014-07-18

Dust particulates immersed in a quasineutral plasma can emit electrons in several important applications. Once electron emission becomes strong enough, the dust enters the positively charged regime where the conventional orbital-motion-limited (OML) theory can break down due to potential-well effects on trapped electrons. A minimal modification of the trapped-passing boundary approximation in the so-called OML(+) approach is shown to accurately predict the dust charge and heat collection flux for a wide range of dust size and temperature.

77 FR 35683 - Agency Information Collection Activities; Proposed Collection; Comment Request; Public Health...

Science.gov (United States)

2012-06-14

...: Submit either electronic or written comments on the collection of information by August 13, 2012. ADDRESSES: Submit electronic comments on the collection of information to http://www.regulations.gov... justification for types of tissues, cells, and plasma, and quantities of plasma and leukocytes collected. 4.1.1...

Curating NASA's future extraterrestrial sample collections: How do we achieve maximum proficiency?

Science.gov (United States)

McCubbin, Francis; Evans, Cynthia; Allton, Judith; Fries, Marc; Righter, Kevin; Zolensky, Michael; Zeigler, Ryan

2016-07-01

Introduction: The Astromaterials Acquisition and Curation Office (henceforth referred to herein as NASA Curation Office) at NASA Johnson Space Center (JSC) is responsible for curating all of NASA's extraterrestrial samples. Under the governing document, NASA Policy Directive (NPD) 7100.10E "Curation of Extraterrestrial Materials", JSC is charged with "The curation of all extraterrestrial material under NASA control, including future NASA missions." The Directive goes on to define Curation as including "…documentation, preservation, preparation, and distribution of samples for research, education, and public outreach." Here we describe some of the ongoing efforts to ensure that the future activities of the NASA Curation Office are working to-wards a state of maximum proficiency. Founding Principle: Curatorial activities began at JSC (Manned Spacecraft Center before 1973) as soon as design and construction planning for the Lunar Receiving Laboratory (LRL) began in 1964 [1], not with the return of the Apollo samples in 1969, nor with the completion of the LRL in 1967. This practice has since proven that curation begins as soon as a sample return mission is conceived, and this founding principle continues to return dividends today [e.g., 2]. The Next Decade: Part of the curation process is planning for the future, and we refer to these planning efforts as "advanced curation" [3]. Advanced Curation is tasked with developing procedures, technology, and data sets necessary for curating new types of collections as envisioned by NASA exploration goals. We are (and have been) planning for future curation, including cold curation, extended curation of ices and volatiles, curation of samples with special chemical considerations such as perchlorate-rich samples, curation of organically- and biologically-sensitive samples, and the use of minimally invasive analytical techniques (e.g., micro-CT, [4]) to characterize samples. These efforts will be useful for Mars Sample Return

Development of a magnetic bead-based method for the collection of circulating extracellular vesicles.

Science.gov (United States)

Shih, Chun-Liang; Chong, Kowit-Yu; Hsu, Shih-Che; Chien, Hsin-Jung; Ma, Ching-Ting; Chang, John Wen-Cheng; Yu, Chia-Jung; Chiou, Chiuan-Chian

2016-01-25

Cells release different types of extracellular vesicles (EVs). These EVs contain biomolecules, including proteins and nucleic acids, from their parent cells, which can be useful for diagnostic applications. The aim of this study was to develop a convenient procedure to collect circulating EVs with detectable mRNA or other biomolecules. Magnetic beads coated with annexin A5 (ANX-beads), which bound to phosphatidylserine moieties on the surfaces of most EVs, were tested for their ability to capture induced apoptotic bodies in vitro and other phosphatidylserine-presenting vesicles in body fluids. Our results show that up to 60% of induced apoptotic bodies could be captured by the ANX-beads. The vesicles captured from cultured media or plasma contained amplifiable RNA. Suitable blood samples for EV collection included EDTA-plasma and serum but not heparin-plasma. In addition, EVs in plasma were labile to freeze-and-thaw cycles. In rodents xenografted with human cancer cells, tumor-derived mRNA could be detected in EVs captured from serum samples. Active proteins could be detected in EVs captured from ascites but not from plasma. In conclusion, we have developed a magnetic bead-based procedure for the collection of EVs from body fluids and proved that captured EVs contain biomolecules from their parent cells, and therefore have great potential for disease diagnosis. Copyright © 2015 Elsevier B.V. All rights reserved.

Planning for the Collection and Analysis of Samples of Martian Granular Materials Potentially to be Returned by Mars Sample Return

Science.gov (United States)

Carrier, B. L.; Beaty, D. W.

2017-12-01

NASA's Mars 2020 rover is scheduled to land on Mars in 2021 and will be equipped with a sampling system capable of collecting rock cores, as well as a specialized drill bit for collecting unconsolidated granular material. A key mission objective is to collect a set of samples that have enough scientific merit to justify returning to Earth. In the case of granular materials, we would like to catalyze community discussion on what we would do with these samples if they arrived in our laboratories, as input to decision-making related to sampling the regolith. Numerous scientific objectives have been identified which could be achieved or significantly advanced via the analysis of martian rocks, "regolith," and gas samples. The term "regolith" has more than one definition, including one that is general and one that is much more specific. For the purpose of this analysis we use the term "granular materials" to encompass the most general meaning and restrict "regolith" to a subset of that. Our working taxonomy includes the following: 1) globally sourced airfall dust (dust); 2) saltation-sized particles (sand); 3) locally sourced decomposed rock (regolith); 4) crater ejecta (ejecta); and, 5) other. Analysis of martian granular materials could serve to advance our understanding areas including habitability and astrobiology, surface-atmosphere interactions, chemistry, mineralogy, geology and environmental processes. Results of these analyses would also provide input into planning for future human exploration of Mars, elucidating possible health and mechanical hazards caused by the martian surface material, as well as providing valuable information regarding available resources for ISRU and civil engineering purposes. Results would also be relevant to matters of planetary protection and ground-truthing orbital observations. We will present a preliminary analysis of the following, in order to generate community discussion and feedback on all issues relating to: What are the

Plasma serotonin in horses undergoing surgery for small intestinal colic

OpenAIRE

Torfs, Sara C; Maes, An A; Delesalle, Catherine J; Pardon, Bart; Croubels, Siska M; Deprez, Piet

2015-01-01

This study compared serotonin concentrations in platelet poor plasma (PPP) from healthy horses and horses with surgical small intestinal (SI) colic, and evaluated their association with postoperative ileus, strangulation and non-survival. Plasma samples (with EDTA) from 33 horses with surgical SI colic were collected at several pre- and post-operative time points. Serotonin concentrations were determined using liquid-chromatography tandem mass spectrometry. Results were compared with those fo...

A needle extraction utilizing a molecularly imprinted-sol-gel xerogel for on-line microextraction of the lung cancer biomarker bilirubin from plasma and urine samples.

Science.gov (United States)

Moein, Mohammad Mahdi; Jabbar, Dunia; Colmsjö, Anders; Abdel-Rehim, Mohamed

2014-10-31

In the present work, a needle trap utilizing a molecularly imprinted sol-gel xerogel was prepared for the on-line microextraction of bilirubin from plasma and urine samples. Each prepared needle could be used for approximately one hundred extractions before it was discarded. Imprinted and non-imprinted sol-gel xerogel were applied for the extraction of bilirubin from plasma and urine samples. The produced molecularly imprinted sol-gel xerogel polymer showed high binding capacity and fast adsorption/desorption kinetics for bilirubin in plasma and urine samples. The adsorption capacity of molecularly imprinted sol-gel xerogel polymer was approximately 60% higher than that of non-imprinted polymer. The effect of the conditioning, washing and elution solvents, pH, extraction time, adsorption capacity and imprinting factor were investigated. The limit of detection and the lower limit of quantification were set to 1.6 and 5nmolL(-1), respectively using plasma or urine samples. The standard calibration curves were obtained within the concentration range of 5-1000nmolL(-1) in both plasma and urine samples. The coefficients of determination values (R(2)) were ≥0.998 for all runs. The extraction recovery was approximately 80% for BR in the human plasma and urine samples. Copyright © 2014 Elsevier B.V. All rights reserved.

Free water {sup 3}H concentration in diet samples collected during 1969-88 in Akita, Japan

Energy Technology Data Exchange (ETDEWEB)

Hisamatsu, S. [Institute for Environmental Sciences, Rokkasho, Aomori (Japan); Inoue, Y.; Miyamoto, K. [National Inst. of Radiological Sciences, Chiba (Japan); Takizawa, Y. [National Institute for Minamata Disease, Minamata, Kumamoto (Japan)

2000-05-01

Fallout {sup 3}H concentrations in diet samples collected during 1969-88 in Akita Prefecture are reported in this paper. Since {sup 3}H is a potential nuclear fuel for fusion reactors in future, its environmental behavior is important for dose assessment of released {sup 3}H from the plants. Tritium in foods is classified into two types; free water {sup 3}H (FWT) and organically-bound {sup 3}H (OBT). The FWT is practically separated by means of freeze-drying, while the OBT is measured with water sample collected by combustion of dried sample. The OBT concentrations in foods and human tissue samples were reported for {sup 3}H originating from nuclear weapon fallout. We already published {sup 3}H concentrations in diet samples collected in Akita City during 1985-88. Although results for the samples collected in U.S.A. and European countries in the 1970s showed higher specific activity of OBT than FWT, our recent results in Japan indicate almost the same specific activity between them. Since the measurements for the samples in 1960s and 1970s are important to understand the long-term movement of {sup 3}H in the environment, we have searched old diet samples. Recently, diet samples collected in Akita Prefecture during 1969-80 were found and obtained for {sup 3}H analysis. The samples were originally gathered for nutrition survey programs and consisted of duplicate diet samples for 1 day from 10-30 persons. Food samples excluding boiled rice which is the staple food was homogenized by electric mixers after adding tap water. Then, the food and the boiled rice samples were stored in a refrigerator at -20degC. Free water in the samples was collected with lyophilization, then {sup 3}H in the water sample was measured after purification with low-level liquid scintillation counters. The free water {sup 3}H concentrations were measured for 57 diet samples (dish excluding boiled rice) and 17 boiled rice samples. The free water {sup 3}H concentrations in diet and rice samples

An evaluation of inductively coupled plasma optical emission spectrometry using electrothermal atomisation sample introduction and photographic plate detection

International Nuclear Information System (INIS)

Khathing, D.T.; Pickford, C.J.

1984-05-01

A photographic radiation measurement approach has been used with an inductively coupled plasma source to evaluate and tabulate the more prominent optical emission lines of 66 elements. Compared with the more common sample introduction technique using nebulisation, increased sensitivity for multielement analysis of small samples was achieved by using a simple graphite electrothermal atomisation system. This was constructed to serve as a dual purpose atomiser ie both for Atomic Absorption and for Inductively Coupled Plasma Emission spectroscopy. The system offers the advantage of a wide multi-elemental coverage, but sensitivities achieved with photographic detection are poorer than those obtained photoelectrically. (author)

Preparation of magnetic ODS-PAN thin-films for microextraction of quetiapine and clozapine in plasma and urine samples followed by HPLC-UV detection.

Science.gov (United States)

Li, Dan; Zou, Juan; Cai, Pei-Shan; Xiong, Chao-Mei; Ruan, Jin-Lan

2016-06-05

In this study, conventional thin-film microextraction (TFME) was endowed with magnetic by introducing superparamagnetic SiO2@Fe3O4 nanoparticles in thin-films. Novel magnetic octadecylsilane (ODS)-polyacrylonitrile (PAN) thin-films were prepared by spraying, and used for the microextraction of quetiapine and clozapine in plasma and urine samples, followed by the detection of HPLC-UV. The influencing factors on the extraction efficiency of magnetic ODS-PAN TFME, including pH, extraction time, desorption solvent, desorption time, and ion strength were investigated systematically. Under the optimal conditions, both analytes showed good linearity over ranges of 0.070-9.000μgmL(-1) and 0.012-9.000μgmL(-1) in plasma and urine samples, respectively, with correlation coefficients (R(2)) above 0.9990. Limits of detection (LODs) for quetiapine in plasma and urine samples were 0.013 and 0.003μgmL(-1), respectively. LODs for clozapine in plasma and urine samples were 0.015 and 0.003μgmL(-1), respectively. The relative standard deviations (RSDs) for quetiapine and clozapine were less than 9.23%. After the validation, the protocol was successfully applied for the determination of quetiapine and clozapine in patients' plasma and urine samples with satisfactory recoveries between 99-110%. The proposed magnetic ODS-PAN TFME was very simple, fast and easy to handle. It showed high potential as a powerful pretreatment technology for routine therapeutic drug monitoring (TDM) in plasma and urine samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Determination of selenium and zinc in rat plasma by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Munoz A, Luis.

1997-01-01

To evaluate the effects on the thyroid function when simple or multiple zinc, selenium and iodine deficiency are induced, research was carried out in laboratory animals. For simultaneously determining the Zn and Se concentration in rat plasma, an instrumental neutron activation analysis technique was applied. A clean laboratory, was used for the preparation of samples. High purity materials were used for sample collection and storage. Irradiation, decay and counting parameters were optimized to obtain the best sensitivity, accuracy and precision analysis. The Zn and Se concentrations were determined from the peak area of gamma-rays of 1115 and 265 KeV respectively. The analytical methodology used was validated with standard reference materials. The procedure used for the analysis, including the phases of collection, treatment of the samples and analytical determination was considered suitable for the study of trace elements in biological samples, especially plasma. (author) [es

Monte Carlo Sampling of Negative-temperature Plasma States

International Nuclear Information System (INIS)

John A. Krommes; Sharadini Rath

2002-01-01

A Monte Carlo procedure is used to generate N-particle configurations compatible with two-temperature canonical equilibria in two dimensions, with particular attention to nonlinear plasma gyrokinetics. An unusual feature of the problem is the importance of a nontrivial probability density function R0(PHI), the probability of realizing a set Φ of Fourier amplitudes associated with an ensemble of uniformly distributed, independent particles. This quantity arises because the equilibrium distribution is specified in terms of Φ, whereas the sampling procedure naturally produces particles states gamma; Φ and gamma are related via a gyrokinetic Poisson equation, highly nonlinear in its dependence on gamma. Expansion and asymptotic methods are used to calculate R0(PHI) analytically; excellent agreement is found between the large-N asymptotic result and a direct numerical calculation. The algorithm is tested by successfully generating a variety of states of both positive and negative temperature, including ones in which either the longest- or shortest-wavelength modes are excited to relatively very large amplitudes

Sustainability of a public system for plasma collection, contract fractionation and plasma-derived medicinal product manufacturing.

Science.gov (United States)

Grazzini, Giuliano; Ceccarelli, Anna; Calteri, Deanna; Catalano, Liviana; Calizzani, Gabriele; Cicchetti, Americo

2013-09-01

In Italy, the financial reimbursement for labile blood components exchanged between Regions is regulated by national tariffs defined in 1991 and updated in 1993-2003. Over the last five years, the need for establishing standard costs of healthcare services has arisen critically. In this perspective, the present study is aimed at defining both the costs of production of blood components and the related prices, as well as the prices of plasma-derived medicinal products obtained by national plasma, to be used for interregional financial reimbursement. In order to analyse the costs of production of blood components, 12 out 318 blood establishments were selected in 8 Italian Regions. For each step of the production process, driving costs were identified and production costs were. To define the costs of plasma-derived medicinal products obtained by national plasma, industrial costs currently sustained by National Health Service for contract fractionation were taken into account. The production costs of plasma-derived medicinal products obtained from national plasma showed a huge variability among blood establishments, which was much lower after standardization. The new suggested plasma tariffs were quite similar to those currently in force. Comparing the overall costs theoretically sustained by the National Health Service for plasma-derived medicinal products obtained from national plasma to current commercial costs, demonstrates that the national blood system could gain a 10% cost saving if it were able to produce plasma for fractionation within the standard costs defined in this study. Achieving national self-sufficiency through the production of plasma-derived medicinal products from national plasma, is a strategic goal of the National Health Service which must comply not only with quality, safety and availability requirements but also with the increasingly pressing need for economic sustainability.

Determination of branched chain amino acids, methionine, phenylalanine, tyrosine and alpha-keto acids in plasma and dried blood samples using HPLC with fluorescence detection.

Science.gov (United States)

Kand'ár, Roman; Záková, Pavla; Jirosová, Jana; Sladká, Michaela

2009-01-01

The determination of branched chain amino acids [BCAA; valine (Val), leucine (Leu), isoleucine (Ile)], alpha-keto acids derived from BCAA [BCKA; alpha-ketoisovaleric acid (KIV), alpha-ketoisocaproic acid (KIC), alpha-ketomethylvaleric acid (KMV)], methionine (Met), phenylalanine (Phe) and tyrosine (Tyr) is currently the most reliable approach for the diagnosis of maple syrup urine disease (MSUD), hypermethioninemia, phenylketonuria (PKU) and tyrosinemia. The aim of this study was to develop rapid and simple HPLC methods for measurement of BCAA, Met, Phe, Tyr and BCKA in plasma and dried blood samples. Samples of peripheral venous blood with EDTA as anticoagulant were obtained from a group of healthy blood donors (n=70, 35 females, 27-41 years of age and 35 males, 28-43 years of age). Blood-spot samples from a group of newborns (n=80, 40 girls and 40 boys 3-5 days of age) were collected onto #903 Specimen Collection Paper and allowed to dry for at least 24 h before analysis. Prior to separation, the amino acids (AA) were derivatized with o-phthaldialdehyde (OPA) and BCKA with o-phenylenediamine (OPD). Reverse phase column chromatography (LiChroCart 125-4 Purospher RP-18e, 5 microm) was used for separation and fluorescence detection used to monitoring of effluent. For AA analysis, 25 mmol/L sodium hydrogenphosphate-methanol (90:10, v/v), pH 6.5+/-0.1 was used as mobile phase A and 100% methanol was used as mobile phase B. Measurement of BCKA used a mixture of methanol and deionized water (55:45, v/v) as mobile phase A and mobile phase B consisted of 100% methanol. Analytical performance of these methods was satisfactory for the determination of all AA and BCKA. The intra-assay and inter-assay coefficients of variation were below 10% and recovery ranged from 90%-110%. We have developed simple, rapid and selective HPLC methods with fluorescence detection for the determination of BCAA, Met, Phe, Tyr and BCKA in plasma and dried blood samples.

Survey of elemental concentrations in lichen samples collected from Sao Paulo State

International Nuclear Information System (INIS)

Saiki, M.; Horimoto, L.K.; Vasconcellos, M.B.A.; Coccaro, D.M.B.; Marcelli, M.P.

2001-01-01

Samples of the lichen Canoparmelia texana collected in seven different sites of Sao Paulo State and one site of the Parana State were analysed by neutron activation analysis in order to obtain information on the air quality in these regions and also to select a region of interest for the evaluation of baseline level of elements in lichen species. Concentrations of the elements Al, As, Br, Ca, Cd, Cl, Co, Cs, Fe, Hf, K, Mg, Mn, Na, Rb, Sb, Sc, Se, Ti, Th, U, V, Zn and lanthanides were determined and a preliminary comparisons was made between the results obtained for samples collected in different sites. (author)

Acceptability of self-collection sampling for HPV-DNA testing in low-resource settings: a mixed methods approach.

Science.gov (United States)

Bansil, Pooja; Wittet, Scott; Lim, Jeanette L; Winkler, Jennifer L; Paul, Proma; Jeronimo, Jose

2014-06-12

Vaginal self-sampling with HPV-DNA tests is a promising primary screening method for cervical cancer. However, women's experiences, concerns and the acceptability of such tests in low-resource settings remain unknown. In India, Nicaragua, and Uganda, a mixed-method design was used to collect data from surveys (N = 3,863), qualitative interviews (N = 72; 20 providers and 52 women) and focus groups (N = 30 women) on women's and providers' experiences with self-sampling, women's opinions of sampling at home, and their future needs. Among surveyed women, 90% provided a self- collected sample. Of these, 75% reported it was easy, although 52% were initially concerned about hurting themselves and 24% were worried about not getting a good sample. Most surveyed women preferred self-sampling (78%). However it was not clear if they responded to the privacy of self-sampling or the convenience of avoiding a pelvic examination, or both. In follow-up interviews, most women reported that they didn't mind self-sampling, but many preferred to have a provider collect the vaginal sample. Most women also preferred clinic-based screening (as opposed to home-based self-sampling), because the sample could be collected by a provider, women could receive treatment if needed, and the clinic was sanitary and provided privacy. Self-sampling acceptability was higher when providers prepared women through education, allowed women to examine the collection brush, and were present during the self-collection process. Among survey respondents, aids that would facilitate self-sampling in the future were: staff help (53%), additional images in the illustrated instructions (31%), and a chance to practice beforehand with a doll/model (26%). Self-and vaginal-sampling are widely acceptable among women in low-resource settings. Providers have a unique opportunity to educate and prepare women for self-sampling and be flexible in accommodating women's preference for self-sampling.

Opioid Concentrations in Oral Fluid and Plasma in Cancer Patients With Pain.

Science.gov (United States)

Heiskanen, Tarja; Langel, Kaarina; Gunnar, Teemu; Lillsunde, Pirjo; Kalso, Eija A

2015-10-01

Measuring opioid concentrations in pain treatment is warranted in situations where optimal opioid analgesia is difficult to reach. To assess the usefulness of oral fluid (OFL) as an alternative to plasma in opioid concentration monitoring in cancer patients on chronic opioid therapy. We collected OFL and plasma samples from 64 cancer patients on controlled-release (CR) oral morphine, CR oral oxycodone, or transdermal (TD) fentanyl for pain. Samples were obtained on up to five separate days. A total of 213 OFL and plasma samples were evaluable. All patients had detectable amounts of the CR or TD opioid in both plasma and OFL samples. The plasma concentrations of oxycodone and fentanyl (determination coefficient R(2) = 0.628 and 0.700, respectively), but not morphine (R(2) = 0.292), were moderately well correlated to the daily opioid doses. In contrast to morphine and fentanyl (mean OFL/plasma ratio 2.0 and 3.0, respectively), the OFL oxycodone concentrations were significantly higher than the respective plasma concentrations (mean OFL/plasma ratio 14.9). An active transporter could explain the much higher OFL vs. plasma concentrations of oxycodone compared with morphine and fentanyl. OFL analysis is well suited for detecting the studied opioids. For morphine and fentanyl, an approximation of the plasma opioid concentrations is obtainable, whereas for oxycodone, the OFL/plasma concentration relationship is too variable for reliable approximation results. Copyright © 2015 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Environmental samples analysis by Atomic Absorption Spectrophotometry and Inductively Coupled Plasma-Optical Emission Spectroscopy

International Nuclear Information System (INIS)

Popescu, I.V.; Iordan, M.; Stihi, C.; Bancuta, A.; Busuioc, G.; Dima, G.; Ciupina, V.; Belc, M.; Vlaicu, Gh.; Marian, R.

2002-01-01

Biological samples are interesting from many aspects of environmental monitoring. By analyzing tree leaves conclusions can be drown regarding the metal loading in the growth medium. So that, starting from assumption that the pollution factors from environmental medium can modify the normal concentration of elements, we decided to control the presence of toxic elements and the deviation from normal state of elements in leaves of different trees from areas situated at different distances of pollution source. The aim of this work is to determine the elemental composition of tree leaves using Atomic Absorption Spectrophotometry (AAS) method and Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) method. Using AAS spectrophotometer SHIMADZU we identified and determined the concentration of: Cd, Co, Cu, Zn, Mn, Cr, Fe, Se, Pb with an instrumental error less than 1% for most of the elements analyzed. The same samples were analyzed by ICP-OES spectrometer, BAIRD ICP2070-Sequential Plasma spectrometer. We identified and determined in leaves of different trees the concentration of Mg, Ca, and Sr with a precision less than 6%. (authors)

Magnetic molecularly imprinted polymer nanoparticles for the solid-phase extraction of paracetamole from plasma samples, followed its determination by HPLC

International Nuclear Information System (INIS)

Azodi-Deilami, Saman; Najafabadi, Alireza Hassani; Asadi, Ebadullah; Abdouss, Majid; Kordestani, Davood

2014-01-01

We are presenting magnetic molecularly imprinted polymer nanoparticles (m-MIPs) for solid-phase extraction and sample clean-up of paracetamole. The m-MIPs were prepared from magnetite (Fe 3 O 4 ) as the magnetic component, paracetamole as the template, methacrylic acid as a functional monomer, and 2-(methacrylamido) ethyl methacrylate as a cross-linker. The m-MIPs were then characterized by transmission electron microscopy, FT-IR spectroscopy, X-ray diffraction and vibrating sample magnetometry. The m-MIPs were applied to the extraction of paracetamole from human blood plasma samples. Following its elution from the column loaded with the m-MIPs with an acetonitrile-buffer (9:1) mixture, it was submitted to HPLC analysis. Paracetamole can be quantified by this method in the 1 μg L −1 to 300 μg L −1 concentration range. The limit of detection and limit of quantification in plasma samples are 0.17 and 0.4 μg L −1 . The preconcentration factor of the m-MIPs is 40. The HPLC method shows good precision (4.5 % at 50 μg L −1 levels) and recoveries (between 83 and 91 %) from spiked plasma samples. (author)

Evaluation of a new simple collection device for sampling of microparticles in exhaled breath.

Science.gov (United States)

Seferaj, Sabina; Ullah, Shahid; Tinglev, Åsa; Carlsson, Sten; Winberg, Jesper; Stambeck, Peter; Beck, Olof

2018-03-12

The microparticle fraction of exhaled breath is of interest for developing clinical biomarkers. Exhaled particles may contain non-volatile components from all parts of the airway system, formed during normal breathing. This study aimed to evaluate a new, simple sampling device, based on impaction, for collecting microparticles from exhaled breath. Performance of the new device was compared with that of the existing SensAbues membrane filter device. The analytical work used liquid chromatography-tandem mass spectrometry methods. The new device collected three subsamples and these were separately analysed from eight individuals. No difference was observed between the centre position (0.91 ng/sample) and the side positions (1.01 ng/sample) using major phosphatidylcholine (PC) 16:0/16:0 as the analyte. Exhaled breath was collected from eight patients on methadone maintenance treatment. The intra-individual variability in measured methadone concentration between the three collectors was 8.7%. In another experiment using patients on methadone maintenance treatment, the sampling efficiency was compared with an established filter device. Compared to the existing device, the efficiency of the new device was 121% greater for methadone and 1450% greater for DPPC. The data from lipid analysis also indicated that a larger fraction of the collected material was from the distal parts. Finally, a study using an optical particle counter indicated that the device preferentially collects the larger particle fraction. In conclusion, this study demonstrates the usefulness of the new device for collecting non-volatile components from exhaled breath. The performance of the device was superior to the filter device in several aspects.

Changes in alt, ast and alp values of plasma and serum samples ...

African Journals Online (AJOL)

Blood samples were obtained from a total of 20 patients that presented with cases of liver malfunction at the Ebonyi State University Teaching Hospital, Abakaliki, Nigeria. The enzyme assays were carried out immediately upon sample collection and separation to obtain the baseline value (BV), and thereafter at specified ...

[Establishment and Management of Multicentral Collection Bio-sample Banks of Malignant Tumors from Digestive System].

Science.gov (United States)

Shen, Si; Shen, Junwei; Zhu, Liang; Wu, Chaoqun; Li, Dongliang; Yu, Hongyu; Qiu, Yuanyuan; Zhou, Yi

2015-11-01

To establish and manage of multicentral collection bio-sample banks of malignant tumors from digestive system, the paper designed a multicentral management system, established the standard operation procedures (SOPs) and leaded ten hospitals nationwide to collect tumor samples. The biobank has been established for half a year, and has collected 695 samples from patients with digestive system malignant tumor. The clinical data is full and complete, labeled in a unified way and classified to be managed. The clinical and molecular biology researches were based on the biobank, and obtained achievements. The biobank provides a research platform for malignant tumor of digestive system from different regions and of different types.

Sample collection and preparation of biofluids and extracts for gas chromatography-mass spectrometry.

Science.gov (United States)

Emwas, Abdul-Hamid M; Al-Talla, Zeyad A; Kharbatia, Najeh M

2015-01-01

To maximize the utility of gas chromatography-mass spectrometry (GC-MS) in metabonomics research, all stages of the experimental design should be standardized, including sample collection, storage, preparation, and sample separation. Moreover, the prerequisite for any GC-MS analysis is that a compound must be volatile and thermally stable if it is to be analyzed using this technique. Since many metabolites are nonvolatile and polar in nature, they are not readily amenable to analysis by GC-MS and require initial chemical derivatization of the polar functional groups in order to reduce the polarity and to increase the thermal stability and volatility of the analytes. In this chapter, an overview is presented of the optimum approach to sample collection, storage, and preparation for gas chromatography-mass spectrometry-based metabonomics with particular focus on urine samples as example of biofluids.

Determination of the neutral oxygen atom density in a plasma reactor loaded with metal samples

Science.gov (United States)

Mozetic, Miran; Cvelbar, Uros

2009-08-01

The density of neutral oxygen atoms was determined during processing of metal samples in a plasma reactor. The reactor was a Pyrex tube with an inner diameter of 11 cm and a length of 30 cm. Plasma was created by an inductively coupled radiofrequency generator operating at a frequency of 27.12 MHz and output power up to 500 W. The O density was measured at the edge of the glass tube with a copper fiber optics catalytic probe. The O atom density in the empty tube depended on pressure and was between 4 and 7 × 1021 m-3. The maximum O density was at a pressure of about 150 Pa, while the dissociation fraction of O2 molecules was maximal at the lowest pressure and decreased with increasing pressure. At about 300 Pa it dropped below 10%. The measurements were repeated in the chamber loaded with different metallic samples. In these cases, the density of oxygen atoms was lower than that in the empty chamber. The results were explained by a drain of O atoms caused by heterogeneous recombination on the samples.

Performance of a hydrostatic sampler for collecting samples at the water-sediment interface in lakes

Directory of Open Access Journals (Sweden)

Fernando PEDROZO

2008-02-01

Full Text Available The water-sediment interface plays a significant role in the determination of the trophic degree of a waterbody. Numerous redox reactions take place there, resulting in the release of contaminants from the sediments to the water column. The aim of the present work was to develop an equipment for collecting samples from the water-sediment interface. Such equipment was to have a simple design, low construction cost, no depth limitations, and high levels of personal safety and to be reliable in the collection of samples. The performance of the hydrostatic sampler thus developed was tested against samples collected either remotely with a corer or directly with syringes by autonomous divers. The hydrostatic sampler permits access to depths where the costs of the traditional diving methodology are expensive, and where working conditions are dangerous for the diver. The hydrostatic sampler provides an additional means of collecting samples from the water-sediment interface, which together with pore-water samples, facilitates the investigation and understanding of chemical mechanisms in lakes, for instance, those that control the P release from sediment to the water column.

Variability and reliability of POP concentrations in multiple breast milk samples collected from the same mothers.

Science.gov (United States)

Kakimoto, Risa; Ichiba, Masayoshi; Matsumoto, Akiko; Nakai, Kunihiko; Tatsuta, Nozomi; Iwai-Shimada, Miyuki; Ishiyama, Momoko; Ryuda, Noriko; Someya, Takashi; Tokumoto, Ieyasu; Ueno, Daisuke

2018-01-13

Risk assessment of infant using a realistic persistent organic pollutant (POP) exposure through breast milk is essential to devise future regulation of POPs. However, recent investigations have demonstrated that POP levels in breast milk collected from the same mother showed a wide range of variation daily and monthly. To estimate the appropriate sample size of breast milk from the same mother to obtain reliable POP concentrations, breast milk samples were collected from five mothers living in Japan from 2006 to 2012. Milk samples from each mother were collected 3 to 6 times a day through 3 to 7 days consecutively. Food samples as the duplicated method were collected from two mothers during the period of breast milk sample collection. Those were employed for POP (PCBs, DDTs, chlordanes, and HCB) analysis. PCB concentrations detected in breast milk samples showed a wide range of variation which was maximum 63 and 60% of relative standard deviation (RSD) in lipid and wet weight basis, respectively. The time course trend of those variations among the mothers did not show any typical pattern. A larger amount of PCB intake through food seemed to affect 10 h after those concentrations in breast milk in lipid weight basis. Intraclass correlation coefficient (ICC) analyses indicated that the appropriate sample size for good reproducibility of POP concentrations in breast milk required at least two samples for lipid and wet weight basis.

Performance of ARCHITECT HCV core antigen test with specimens from US plasma donors and injecting drug users.

Science.gov (United States)

Mixson-Hayden, Tonya; Dawson, George J; Teshale, Eyasu; Le, Thao; Cheng, Kevin; Drobeniuc, Jan; Ward, John; Kamili, Saleem

2015-05-01

Hepatitis C virus (HCV) core antigen is a serological marker of current HCV infection. The aim of this study was mainly to evaluate the performance characteristics of the ARCHITECT HCV core antigen assay with specimens from US plasma donors and injecting drug users. A total of 551 serum and plasma samples with known anti-HCV and HCV RNA status were tested for HCV core antigen using the Abbott ARCHITECT HCV core antigen test. HCV core antigen was detectable in 100% of US plasma donor samples collected during the pre-seroconversion phase of infection (anti-HCV negative/HCV RNA positive). Overall sensitivity of the HCV core antigen assay was 88.9-94.3% in samples collected after seroconversion. The correlation between HCV core antigen and HCV RNA titers was 0.959. HCV core antigen testing may be reliably used to identify current HCV infection. Published by Elsevier B.V.

A Comprehensive Software and Database Management System for Glomerular Filtration Rate Estimation by Radionuclide Plasma Sampling and Serum Creatinine Methods.

Science.gov (United States)

Jha, Ashish Kumar

2015-01-01

Glomerular filtration rate (GFR) estimation by plasma sampling method is considered as the gold standard. However, this method is not widely used because the complex technique and cumbersome calculations coupled with the lack of availability of user-friendly software. The routinely used Serum Creatinine method (SrCrM) of GFR estimation also requires the use of online calculators which cannot be used without internet access. We have developed user-friendly software "GFR estimation software" which gives the options to estimate GFR by plasma sampling method as well as SrCrM. We have used Microsoft Windows(®) as operating system and Visual Basic 6.0 as the front end and Microsoft Access(®) as database tool to develop this software. We have used Russell's formula for GFR calculation by plasma sampling method. GFR calculations using serum creatinine have been done using MIRD, Cockcroft-Gault method, Schwartz method, and Counahan-Barratt methods. The developed software is performing mathematical calculations correctly and is user-friendly. This software also enables storage and easy retrieval of the raw data, patient's information and calculated GFR for further processing and comparison. This is user-friendly software to calculate the GFR by various plasma sampling method and blood parameter. This software is also a good system for storing the raw and processed data for future analysis.

A simple radioimmunoassay for plasma cortisol

International Nuclear Information System (INIS)

Seth, J.; Brown, L.M.

1978-01-01

A simple radioimmunoassay (RIA) for plasma cortisol is described which combines the advantages of (i) direct analysis of untreated plasma samples, (ii) use of solid-coupled anti-cortisol antibodies and (iii) use of a gamma-labelled radioligand. The reagents are relatively easily prepared and stable, and the analysis can be completed in 4 h. Inter-assay precision (C.V.) is 8-11%. Critical examination of specificity using high pressure liquid chromatography showed that 23-35% of the immunoassayable material in plasma was not cortisol. RIA results on samples collected under basal conditions were an average 40 nmol/l lower than fluorimetric results, while in insulin hypoglycaemia and synacthen (ACTH) stimulation tests, this difference increased to over 100 nmol/l. The RIA is technically more simple than fluorimetric, competitive-protein-binding, and many RIA methods, and can be used with advantage in the routine investigation of adrenocortical function. However, using the present antiserum, the RIA is not applicable to investigations on patients receiving metyrapone, nor in suspected cases of congenital adrenal hyperplasia. (Auth.)

Single injection 51Cr EDTA plasma clearance determination in children using capillary blood samples

International Nuclear Information System (INIS)

Broechner-Mortensen, J.; Christoffersen, J.

1977-01-01

The reliability of a determination of the total 51 Cr EDTA plasma clearance (e) (and with it the glomerular filtration rate), by a simplified single injection method (injected dose: 4.5 μCi per kg b.w.) using capillary blood samples (0.2 ml), was investigated in twenty children. Clearance values determined from capillary blood samples did not differ significantly from those measured simultaneously from venous blood samples, the mean ratio+-SD being 1.02+-0.06(n = 10). The reproducibility (total day-to-day variation) of E determined from capillary blood samples was 6.7% in children with decreased renal function (n = 3) and 6.9% in children with normal renal function (n = 7). The present data indicate that the use of capillary blood samples is an accurate and very precise approach for determination of E in children. (Auth.)

Collective ion acceleration by relativistic electron beams in plasmas

International Nuclear Information System (INIS)

Galvez, M.; Gisler, G.

1991-01-01

A two-dimensional fully electromagnetic particle-in-cell code is used to simulate the interaction of a relativistic electron beam injected into a finite-size background neutral plasma. The simulations show that the background electrons are pushed away from the beam path, forming a neutralizing ion channel. Soon after the beam head leaves the plasma, a virtual cathode forms which travels away with the beam. However, at later times a second, quasi-stationary, virtual cathode forms. Its position and strength depends critically on the parameters of the system which critically determines the efficiency of the ion acceleration process. The background ions trapped in the electrostatic well of the virtual cathode are accelerated and at later times, the ions as well as the virtual cathode drift away from the plasma region. The surfing of the ions in the electrostatic well produces an ion population with energies several times the initial electron beam energy. It is found that optimum ion acceleration occurs when the beam-to-plasma density ratio is near unity. When the plasma is dense, the beam is a weak perturbation and accelerates few ions, while when the plasma is tenuous, the beam is not effectively neutralized, and a virtual cathode occurs right at the injection plane. The simulations also show that, at the virtual cathode position, the electron beam is pinched producing a self-focusing phenomena

Archival policies and collections database for the Woods Hole Science Center's marine sediment samples

Science.gov (United States)

Buczkowski, Brian J.; Kelsey, Sarah A.

2007-01-01

The Woods Hole Science Center of the U.S. Geological Survey (USGS) has been an active member of the Woods Hole research community, Woods Hole, Massachusetts, for over 40 years. In that time there have been many projects that involved the collection of sediment samples conducted by USGS scientists and technicians for the research and study of seabed environments and processes. These samples were collected at sea or near shore and then brought back to the Woods Hole Science Center (WHSC) for analysis. While at the center, samples are stored in ambient temperature, refrigerated and freezing conditions ranging from +2º Celsius to -18º Celsius, depending on the best mode of preparation for the study being conducted or the duration of storage planned for the samples. Recently, storage methods and available storage space have become a major concern at the WHSC. The core and sediment archive program described herein has been initiated to set standards for the management, methods, and duration of sample storage. A need has arisen to maintain organizational consistency and define storage protocol. This handbook serves as a reference and guide to all parties interested in using and accessing the WHSC's sample archive and also defines all the steps necessary to construct and maintain an organized collection of geological samples. It answers many questions as to the way in which the archive functions.

Methods for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry

Science.gov (United States)

Chan, George C. Y. [Bloomington, IN; Hieftje, Gary M [Bloomington, IN

2010-08-03

A method for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry (ICP-AES). ICP-AES analysis is performed across a plurality of selected locations in the plasma on an unknown sample, collecting the light intensity at one or more selected wavelengths of one or more sought-for analytes, creating a first dataset. The first dataset is then calibrated with a calibration dataset creating a calibrated first dataset curve. If the calibrated first dataset curve has a variability along the location within the plasma for a selected wavelength, errors are present. Plasma-related errors are then corrected by diluting the unknown sample and performing the same ICP-AES analysis on the diluted unknown sample creating a calibrated second dataset curve (accounting for the dilution) for the one or more sought-for analytes. The cross-over point of the calibrated dataset curves yields the corrected value (free from plasma related errors) for each sought-for analyte.

JSC Advanced Curation: Research and Development for Current Collections and Future Sample Return Mission Demands

Science.gov (United States)

Fries, M. D.; Allen, C. C.; Calaway, M. J.; Evans, C. A.; Stansbery, E. K.

2015-01-01

Curation of NASA's astromaterials sample collections is a demanding and evolving activity that supports valuable science from NASA missions for generations, long after the samples are returned to Earth. For example, NASA continues to loan hundreds of Apollo program samples to investigators every year and those samples are often analyzed using instruments that did not exist at the time of the Apollo missions themselves. The samples are curated in a manner that minimizes overall contamination, enabling clean, new high-sensitivity measurements and new science results over 40 years after their return to Earth. As our exploration of the Solar System progresses, upcoming and future NASA sample return missions will return new samples with stringent contamination control, sample environmental control, and Planetary Protection requirements. Therefore, an essential element of a healthy astromaterials curation program is a research and development (R&D) effort that characterizes and employs new technologies to maintain current collections and enable new missions - an Advanced Curation effort. JSC's Astromaterials Acquisition & Curation Office is continually performing Advanced Curation research, identifying and defining knowledge gaps about research, development, and validation/verification topics that are critical to support current and future NASA astromaterials sample collections. The following are highlighted knowledge gaps and research opportunities.

Direct measurements of sample heating by a laser-induced air plasma in pre-ablation spark dual-pulse laser-induced breakdown spectroscopy (LIBS).

Science.gov (United States)

Register, Janna; Scaffidi, Jonathan; Angel, S Michael

2012-08-01

Direct measurements of temperature changes were made using small thermocouples (TC), placed near a laser-induced air plasma. Temperature changes up to ~500 °C were observed. From the measured temperature changes, estimates were made of the amount of heat absorbed per unit area. This allowed calculations to be made of the surface temperature, as a function of time, of a sample heated by the air plasma that is generated during orthogonal pre-ablation spark dual-pulse (DP) LIBS measurements. In separate experiments, single-pulse (SP) LIBS emission and sample ablation rate measurements were performed on nickel at sample temperatures ranging from room temperature to the maximum surface temperature that was calculated using the TC measurement results (500 °C). A small, but real sample temperature-dependent increase in both SP LIBS emission and the rate of sample ablation was found for nickel samples heated up to 500 °C. Comparison of DP LIBS emission enhancement values for bulk nickel samples at room temperature versus the enhanced SP LIBS emission and sample ablation rates observed as a function of increasing sample temperature suggests that sample heating by the laser-induced air plasma plays only a minor role in DP LIBS emission enhancement.

INR calibration of Owren-type prothrombin time based on the relationship between PT% and INR utilizing normal plasma samples.

Science.gov (United States)

Lindahl, Tomas L; Egberg, Nils; Hillarp, Andreas; Ødegaard, Ole R; Edlund, Bror; Svensson, Jan; Sandset, Per M; Rånby, Mats

2004-06-01

Prothrombin time (PT) is clinically important and is used to monitor oral anticoagulant therapy. To obtain PT results in international normalized ratio (INR), the current standardization procedure is complex and involves reference reagents. The PT of diluted plasma samples can be determined with a combined thromboplastin (the Owren-type procedure), but not necessarily with a plain thromboplastin (the Quick-type procedure). Owren-type PT procedures can therefore, as an alternative to the INR calibration, be calibrated with diluted normal plasma to give PT results in percent of normal PT activity (PT%). The present study explored if a plasma-based calibration of an Owren-type PT procedure can be used to obtain results in INR. The approach was to establish a relationship between PT% and INR by multi-center analysis of 365 samples from healthy individuals and patients on warfarin treatment. INR values were obtained by manual Quick-type reference procedure and PT% values by various automated Owren-type procedures. A relationship INR = (1/PT% + 0.018)/0.028 was found. A calibration procedure, based on the relationship, was investigated. Calibrators were the median PT of 21 normal plasma at dilutions representing 100%, 50%, 25%, 12.5% and 6.25% of normal PT activity. These were assigned INR values of 1.00, 1.36, 2.07, 3.05 and 6.36. Calibration of various Owren-type assays was repeatedly performed by 5 expert laboratories during 3 consecutive years. The INR values of certain lyophilised or frozen control plasmas were determined. The frozen control plasmas had externally assigned INR values according to WHO guide-lines. Within the laboratory, CV was typically below 3%. No appreciable difference among the results of the different laboratories or the three assay occasions was found. Externally assigned and INR values were essentially identical to those found. These and other results indicated that the calibration procedure was reproducible, precise and accurate. Thus, an

Blood plasma sample preparation method to determine thyroid hormone-disrupting compounds in Effect-Directed Analysis

NARCIS (Netherlands)

Simon, E.; Bytingsvik, J.; Jonker, W.; Leonards, P.E.G.; de Boer, J.; Jenssen, B.M.; Lie, E.; Aars, J.; Hamers, T.H.M.; Lamoree, M.H.

2011-01-01

A sample preparation method combining solid-phase extraction (SPE) and liquid-liquid extraction (LLE) was developed to be used in Effect-Directed Analysis (EDA) of blood plasma. Until now such a method was not available. It can be used for extraction of a broad range of thyroid hormone

Simulated Irradiation of Samples in HFIR for use as Possible Test Materials in the MPEX (Material Plasma Exposure Experiment) Facility

Energy Technology Data Exchange (ETDEWEB)

Ellis, Ronald James [ORNL; Rapp, Juergen [ORNL

2014-01-01

The importance of Plasma Material Interaction (PMI) is a major concern in fusion reactor design and analysis. The Material-Plasma Exposure eXperiment (MPEX) facility will explore PMI under fusion reactor plasma conditions. Samples with accumulated displacements per atom (DPA) damage produced by irradiations in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) will be studied in the MPEX facility. The project presented in this paper involved performing assessments of the induced radioactivity and resulting radiation fields of a variety of potential fusion reactor materials. The scientific code packages MCNP and SCALE were used to simulate irradiation of the samples in HFIR; generation and depletion of nuclides in the material and the subsequent composition, activity levels, gamma radiation fields, and resultant dose rates as a function of cooling time. These state-of-the-art simulation methods were used in addressing the challenge of the MPEX project to minimize the radioactive inventory in the preparation of the samples for inclusion in the MPEX facility.

Evidence for plasma effect on charge collection efficiency in proton irradiated GaAs detectors

CERN Document Server

Nava, F; Canali, C; Vittone, E; Polesello, P; Biggeri, U; Leroy, C

1999-01-01

The radiation damage in 100 mu m thick Schottky diodes made on semi-insulating undoped GaAs materials, were studied using alpha-, beta-, proton- and gamma-spectroscopy as well as I-V measurements. The results have been analysed within the framework of the Hecht model to investigate the influence of the plasma produced by short-range strongly ionising particles on the detector performance after 24 GeV proton irradiation. It has been found that with the mean free drift lengths for electrons and holes determined from alpha-spectra in overdepleted detectors, the charge collection efficiency for beta-particles, cce subbeta, is well predicted in the unirradiated detectors, while in the most irradiated ones, the cce subbeta is underestimated by more than 40%. The observed disagreement can be explained by assuming that the charge carrier recombination in the plasma region of such detectors, becomes significant.

Validation of Marek's disease diagnosis and monitoring of Marek's disease vaccines from samples collected in FTA cards.

Science.gov (United States)

Cortes, Aneg L; Montiel, Enrique R; Gimeno, Isabel M

2009-12-01

The use of Flinders Technology Associates (FTA) filter cards to quantify Marek's disease virus (MDV) DNA for the diagnosis of Marek's disease (MD) and to monitor MD vaccines was evaluated. Samples of blood (43), solid tumors (14), and feather pulp (FP; 36) collected fresh and in FTA cards were analyzed. MDV DNA load was quantified by real-time PCR. Threshold cycle (Ct) ratios were calculated for each sample by dividing the Ct value of the internal control gene (glyceraldehyde-3-phosphate dehydrogenase) by the Ct value of the MDV gene. Statistically significant correlation (P FTA cards by using Pearson's correlation test. Load of serotype 1 MDV DNA was quantified in 24 FP, 14 solid tumor, and 43 blood samples. There was a statistically significant correlation between FP (r = 0.95), solid tumor (r = 0.94), and blood (r = 0.9) samples collected fresh and in FTA cards. Load of serotype 2 MDV DNA was quantified in 17 FP samples, and the correlation between samples collected fresh and in FTA cards was also statistically significant (Pearson's coefficient, r = 0.96); load of serotype 3 MDV DNA was quantified in 36 FP samples, and correlation between samples taken fresh and in FTA cards was also statistically significant (r = 0.84). MDV DNA samples extracted 3 days (t0) and 8 months after collection (t1) were used to evaluate the stability of MDV DNA in archived samples collected in FTA cards. A statistically significant correlation was found for serotype 1 (r = 0.96), serotype 2 (r = 1), and serotype 3 (r = 0.9). The results show that FTA cards are an excellent media to collect, transport, and archive samples for MD diagnosis and to monitor MD vaccines. In addition, FTA cards are widely available, inexpensive, and adequate for the shipment of samples nationally and internationally.

Hypergravity synthesis of graphitic carbon nanomaterial in glide arc plasma

NARCIS (Netherlands)

Šperka, J.; Soucek, P.; van Loon, J.J.W.A.; Dowson, A.; Schwarz, C.; Krause, J.; Butenko, Y.; Kroesen, G.; Kudrle, V.

2014-01-01

A nanostructured carbon material was synthesized using a methane/helium glide arc plasma under standard and increased gravity. Material analysis performed on samples collected from an effluent gas filter showed that the deposited material was present in the form of carbon nanoparticles. They

Impact of collection container material and holding times on sample integrity for mercury and methylmercury in water

Energy Technology Data Exchange (ETDEWEB)

Riscassi, Ami L [ORNL; Miller, Carrie L [ORNL; Brooks, Scott C [ORNL

2014-01-01

Mercury (Hg) and methylmercury (MeHg) concentrations in streamwater can vary on short timescales (hourly or less) during storm flow and on a diel cycle; the frequency and timing of sampling required to accurately characterize these dynamics may be difficult to accomplish manually. Automated sampling can assist in sample collection; however use has been limited for Hg and MeHg analysis due to stability concerns of trace concentrations during extended storage times. We examined the viability of using automated samplers with disposable low-density polyethylene (LDPE) sample bags to collect industrially contaminated streamwater for unfiltered and filtered Hg and MeHg analysis. Specifically we investigated the effect of holding times ranging from hours to days on streamwater collected during baseflow and storm flow. Unfiltered and filtered Hg and MeHg concentrations decreased with increases in time prior to sample processing; holding times of 24 hours or less resulted in concentration changes (mean 11 7% different) similar to variability in duplicates collected manually during analogous field conditions (mean 7 10% different). Comparisons of samples collected with manual and automated techniques throughout a year for a wide range of stream conditions were also found to be similar to differences observed between duplicate grab samples. These results demonstrate automated sampling into LDPE bags with holding times of 24 hours or less can be effectively used to collect streamwater for Hg and MeHg analysis, and encourage the testing of these materials and methods for implementation in other aqueous systems where high-frequency sampling is warranted.

The effect of a plasma needle on bacteria in planktonic samples and on peripheral blood mesenchymal stem cells

International Nuclear Information System (INIS)

Lazovic, Sasa; Puac, Nevena; Maletic, Dejan; Malovic, Gordana; Petrovic, Zoran; Miletic, Maja; Pavlica, Dusan; Jovanovic, Milena; Milenkovic, Pavle; Bugarski, Diana; Mojsilovic, Slavko

2010-01-01

In this paper, we study the application of a plasma needle to induce necrosis in planktonic samples containing a single breed of bacteria. Two different types of bacteria, Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922), were covered in this study. In all experiments with bacteria, the samples were liquid suspensions of several different concentrations of bacteria prepared according to the McFarland standard. The second system studied in this paper was human peripheral blood mesenchymal stem cells (hPB-MSC). In the case of hPB-MSC, two sets of experiments were performed: when cells were covered with a certain amount of liquid (indirect) and when the cell sample was in direct contact with the plasma. Most importantly, the study is made with the aim to see the effects when the living cells are in a liquid medium, which normally acts as protection against the many agents that may be released by plasmas. It was found that a good effect may be expected for a wide range of initial cell densities and operating conditions causing destruction of several orders of magnitude even under the protection of a liquid. It was established independently that a temperature increase could not affect the cells under the conditions of our experiment, so the effect could originate only from the active species produced by the plasma. In the case of those hPB-MSC that were not protected by a liquid, gas flow proved to produce a considerable effect, presumably due to poor adhesion of the cells, but in a liquid the effect was only due to the plasma. Further optimization of the operation may be attempted, opening up the possibility of localized in vivo sterilization.

The effect of a plasma needle on bacteria in planktonic samples and on peripheral blood mesenchymal stem cells

Energy Technology Data Exchange (ETDEWEB)

Lazovic, Sasa; Puac, Nevena; Maletic, Dejan; Malovic, Gordana; Petrovic, Zoran [Institute of Physics, Pregrevica 118, 11080 Belgrade (Serbia); Miletic, Maja; Pavlica, Dusan; Jovanovic, Milena; Milenkovic, Pavle [Faculty of Stomatology, Dr Subotica 8, 11000 Belgrade (Serbia); Bugarski, Diana; Mojsilovic, Slavko, E-mail: lazovic@ipb.ac.r [Institute for Medical Research, Dr Subotica-starijeg 4, 11000 Belgrade (Serbia)

2010-08-15

In this paper, we study the application of a plasma needle to induce necrosis in planktonic samples containing a single breed of bacteria. Two different types of bacteria, Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922), were covered in this study. In all experiments with bacteria, the samples were liquid suspensions of several different concentrations of bacteria prepared according to the McFarland standard. The second system studied in this paper was human peripheral blood mesenchymal stem cells (hPB-MSC). In the case of hPB-MSC, two sets of experiments were performed: when cells were covered with a certain amount of liquid (indirect) and when the cell sample was in direct contact with the plasma. Most importantly, the study is made with the aim to see the effects when the living cells are in a liquid medium, which normally acts as protection against the many agents that may be released by plasmas. It was found that a good effect may be expected for a wide range of initial cell densities and operating conditions causing destruction of several orders of magnitude even under the protection of a liquid. It was established independently that a temperature increase could not affect the cells under the conditions of our experiment, so the effect could originate only from the active species produced by the plasma. In the case of those hPB-MSC that were not protected by a liquid, gas flow proved to produce a considerable effect, presumably due to poor adhesion of the cells, but in a liquid the effect was only due to the plasma. Further optimization of the operation may be attempted, opening up the possibility of localized in vivo sterilization.

The effect of a plasma needle on bacteria in planktonic samples and on peripheral blood mesenchymal stem cells

Science.gov (United States)

Lazović, Saša; Puač, Nevena; Miletić, Maja; Pavlica, Dušan; Jovanović, Milena; Bugarski, Diana; Mojsilović, Slavko; Maletić, Dejan; Malović, Gordana; Milenković, Pavle; Petrović, Zoran

2010-08-01

In this paper, we study the application of a plasma needle to induce necrosis in planktonic samples containing a single breed of bacteria. Two different types of bacteria, Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922), were covered in this study. In all experiments with bacteria, the samples were liquid suspensions of several different concentrations of bacteria prepared according to the McFarland standard. The second system studied in this paper was human peripheral blood mesenchymal stem cells (hPB-MSC). In the case of hPB-MSC, two sets of experiments were performed: when cells were covered with a certain amount of liquid (indirect) and when the cell sample was in direct contact with the plasma. Most importantly, the study is made with the aim to see the effects when the living cells are in a liquid medium, which normally acts as protection against the many agents that may be released by plasmas. It was found that a good effect may be expected for a wide range of initial cell densities and operating conditions causing destruction of several orders of magnitude even under the protection of a liquid. It was established independently that a temperature increase could not affect the cells under the conditions of our experiment, so the effect could originate only from the active species produced by the plasma. In the case of those hPB-MSC that were not protected by a liquid, gas flow proved to produce a considerable effect, presumably due to poor adhesion of the cells, but in a liquid the effect was only due to the plasma. Further optimization of the operation may be attempted, opening up the possibility of localized in vivo sterilization.

Comparison of Three Sample Preparation Procedures for the Quantification of L-Arginine, Asymmetric Dimethylarginine, and Symmetric Dimethylarginine in Human Plasma Using HPLC-FLD

Science.gov (United States)

Schou-Pedersen, Anne Marie Voigt

2018-01-01

Increased asymmetric dimethylarginine (ADMA) in human plasma has been associated with reduced generation of nitric oxide, leading to atherosclerotic diseases. ADMA may therefore be an important biomarker for cardiovascular disease. In the present study, three sample preparation techniques were compared regarding the quantification of L-arginine and ADMA in human plasma: (A) protein precipitation (PP) based on aqueous trichloroacetic acid (TCA), (B) PP using a mixture of ammonia and acetonitrile, and (C) solid-phase extraction (SPE). The samples were analysed by using high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The analytical performance of (A) was comparable with that of (C), demonstrating recoveries of >90%, coefficient of variations (CVs, %) of 0.994), precision (sample preparation of human plasma samples before HPLC-FLD in providing important information regarding elevated ADMA concentrations. PMID:29484214

78 FR 79009 - Proposed Information Collection; Radiation Sampling and Exposure Records (Pertains to Underground...

Science.gov (United States)

2013-12-27

... soliciting comments concerning the proposed information collection for updating Radiation Sampling and... exposed with no adverse effects have been established and are expressed as working levels (WL). The... mandatory samplings. Records must include the sample date, location, and results, and must be retained at...

A computational platform for MALDI-TOF mass spectrometry data: application to serum and plasma samples.

Science.gov (United States)

Mantini, Dante; Petrucci, Francesca; Pieragostino, Damiana; Del Boccio, Piero; Sacchetta, Paolo; Candiano, Giovanni; Ghiggeri, Gian Marco; Lugaresi, Alessandra; Federici, Giorgio; Di Ilio, Carmine; Urbani, Andrea

2010-01-03

Mass spectrometry (MS) is becoming the gold standard for biomarker discovery. Several MS-based bioinformatics methods have been proposed for this application, but the divergence of the findings by different research groups on the same MS data suggests that the definition of a reliable method has not been achieved yet. In this work, we propose an integrated software platform, MASCAP, intended for comparative biomarker detection from MALDI-TOF MS data. MASCAP integrates denoising and feature extraction algorithms, which have already shown to provide consistent peaks across mass spectra; furthermore, it relies on statistical analysis and graphical tools to compare the results between groups. The effectiveness in mass spectrum processing is demonstrated using MALDI-TOF data, as well as SELDI-TOF data. The usefulness in detecting potential protein biomarkers is shown comparing MALDI-TOF mass spectra collected from serum and plasma samples belonging to the same clinical population. The analysis approach implemented in MASCAP may simplify biomarker detection, by assisting the recognition of proteomic expression signatures of the disease. A MATLAB implementation of the software and the data used for its validation are available at http://www.unich.it/proteomica/bioinf. (c) 2009 Elsevier B.V. All rights reserved.

Detection of EGFR mutations in plasma and biopsies from non-small cell lung cancer patients by allele-specific PCR assays

DEFF Research Database (Denmark)

Weber, Britta; Meldgaard, Peter; Hager, Henrik

2014-01-01

samples with allele-specific PCR assays. METHODS: Pairs of the diagnostic biopsy and plasma obtained just prior to start of erlotinib treatment were collected from 199 patients with adenocarcinoma of non-small-cell lung cancer. DNA from both sample types was isolated and examined for the presence...... of mutations in exons 18-21 of the EGFR gene, employing the cobas(®) EGFR Tissue Test and cobas(®) EGFR Blood Test (in development, Roche Molecular Systems, Inc., CA, USA). RESULTS: Test results were obtained in all 199 (100%) plasma samples and 196/199 (98%) of the biopsies. EGFR-activating mutations were...... identified in 24/199 (12%) plasma samples and 28/196 (14%) biopsy samples, and 17/196 (9%) matched pairs contained the same mutation. Six EGFR mutations were present only in plasma samples but not in the biopsy samples. The overall concordance of the EGFR gene mutations detected in plasma and biopsy tissue...

Comparison of semen parameters in samples collected by masturbation at a clinic and at home.

Science.gov (United States)

Elzanaty, Saad; Malm, Johan

2008-06-01

To investigate differences in semen quality between samples collected by masturbation at a clinic and at home. Cross-sectional study. Fertility center. Three hundred seventy-nine men assessed for infertility. None. Semen was analyzed according to World Health Organization guidelines. Seminal markers of epididymal (neutral alpha-glucosidase), prostatic (prostate-specific antigen and zinc), and seminal vesicle (fructose) function were measured. Two patient groups were defined according to sample collection location: at a clinic (n = 273) or at home (n = 106). Compared with clinic-collected semen, home-collected samples had statistically significantly higher values for sperm concentration, total sperm count, rapid progressive motility, and total count of progressive motility. Semen volume, proportion of normal sperm morphology, neutral alpha-glucosidase, prostate-specific antigen, zinc, and fructose did not differ significantly between groups. An abnormal sperm concentration (masturbation at home compared with at a clinic. This should be taken into consideration in infertility investigations.

Determination of uranium isotopic composition and {sup 236}U content of soil samples and hot particles using inductively coupled plasma mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Boulyga, S.F. [Radiation Physics and Chemistry Problems Inst., Minsk (Belarus); Becker, J.S. [Central Department for Analytical Chemistry, Research Centre Juelich (Germany)

2001-07-01

As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The {sup 236}U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. Nuclear track radiography was applied for the identification and extraction of hot radioactive particles from soil samples. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on double-focusing inductively coupled plasma mass spectrometry (DF-ICP-MS) with a MicroMist nebulizer and a direct injection high-efficiency nebulizer (DIHEN). The performance of the DF-ICP-MS with a quartz DIHEN and plasma shielded torch was studied. Overall detection efficiencies of 4 x 10{sup -4} and 10{sup -3} counts per atom were achieved for {sup 238}U in DF-ICP-QMS with the MicroMist nebulizer and DIHEN, respectively. The rate of formation of uranium hydride ions UH{sup +}/U{sup +} was 1.2 x 10{sup -4} and 1.4 x 10{sup -4}, respectively. The precision of short-term measurements of uranium isotopic ratios (n = 5) in 1 {mu}g L{sup -1} NBS U-020 standard solution was 0.11% ({sup 238}U/{sup 235}U) and 1.4% ({sup 236}U/{sup 238}U) using a MicroMist nebulizer and 0.25% ({sup 235}U/{sup 238}U) and 1.9% ({sup 236}U/{sup 238}U) using a DIHEN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the {sup 236}U/{sup 238}U ratio ranged from 10{sup -5} to 10{sup -3}. Results obtained with ICP-MS, {alpha}- and {gamma}-spectrometry showed differences in the migration properties of spent uranium, plutonium, and americium. The isotopic ratio of uranium was also measured in hot particles extracted from soil samples. (orig.)

NEXAFS spectroscopy with a laser plasma x-ray source on soil samples

International Nuclear Information System (INIS)

Sedlmair, J; Geber, S-C; Thieme, J; Peth, C; Mann, K

2009-01-01

Humic substances are post-mortal organic substances without an exact chemical structure. Their large specific surface is important for transport processes, especially in soils. We analyzed the NEXAFS spectra of humic substances, from which the amount of certain chemical compounds such as aromatic and aliphatic groups can be verified by the resonances of their binding energy. For the experiments, a compact table-top setup working with a laser plasma source was used. NEXAFS makes it possible to distinguish between samples, even if they contain the same composits, because information about the specific functional groups in the sample is supplied. The evaluation was carried out using the program SpecFit. It was developed on IDL within our group and allows to fit the NEXAFS-data with a combination of arctangent, Gaussian and Lorentzian curves.

NEXAFS spectroscopy with a laser plasma x-ray source on soil samples

Energy Technology Data Exchange (ETDEWEB)

Sedlmair, J; Geber, S-C; Thieme, J [Institute for X-Ray Physics, Georg-August-University Goettingen, Friedrich-Hund-Platz 1, D-37077 (Germany); Peth, C; Mann, K, E-mail: jsedlma@gwdg.d [Laser-Laboratorium Goettingen e.V., Hans-Adolf-Krebs-Weg 1, D-37077 (Germany)

2009-09-01

Humic substances are post-mortal organic substances without an exact chemical structure. Their large specific surface is important for transport processes, especially in soils. We analyzed the NEXAFS spectra of humic substances, from which the amount of certain chemical compounds such as aromatic and aliphatic groups can be verified by the resonances of their binding energy. For the experiments, a compact table-top setup working with a laser plasma source was used. NEXAFS makes it possible to distinguish between samples, even if they contain the same composits, because information about the specific functional groups in the sample is supplied. The evaluation was carried out using the program SpecFit. It was developed on IDL within our group and allows to fit the NEXAFS-data with a combination of arctangent, Gaussian and Lorentzian curves.

Validation and application of a liquid chromatography-electrospray ionization mass spectrometric method for determination of mazindol in human plasma and urine.

Science.gov (United States)

de Oliveira, Marcella Herbstrith; Ferreira, Pâmela Cristina Lukasewicz; Carlos, Graciela; Salazar, Fernanda Rodrigues; Bergold, Ana Maria; Pechansky, Flavio; Limberger, Renata Pereira; Fröehlich, Pedro Eduardo

2016-01-01

Even after removal of some stimulants, like fenproporex, amfepramone and mazindol, from Brazilian market, the use of these substances is still high, especially by drivers. Mazindol is the second most used anorectic agent in the world acting as an indirect sympathomimetic agonist, having stimulatory action on central nervous system. Plasma is a good matrix to monitor since it reflects the psychomotor effects of these drugs, but unlike urine has an invasive collection; drug levels and detection time are quite low. The method involved a liquid-liquid extraction of the samples and a LC-MS analysis was fully validated. Method was used to analyze samples of urine and plasma collected from health volunteers in a period of 24h. Metabolite of mazindol was synthesized using alkaline conditions. After validation the method proved to be adequate to analyze samples collected from health volunteers. Method was linear in the concentration range of 0.1-10ng/mL (r=0.9982) for plasma and 5-50ng/mL (r=0.9973) for urine. Analysis of the samples showed that mazindol can be detected after 1h of administration and that concentration levels in urine were always higher than in plasma. Mazindol metabolite was detected only in urine. Copyright © 2015 Elsevier Inc. All rights reserved.

Biocompatible in-tube solid phase microextraction coupled with liquid chromatography-fluorescence detection for determination of interferon α in plasma samples.

Science.gov (United States)

Chaves, Andréa R; Silva, Bruno J G; Lanças, Fernando M; Queiroz, Maria Eugênia C

2011-05-27

The present work demonstrates the successful application of automated biocompatible in-tube solid-phase microextraction coupled with liquid chromatography (in-tube SPME/LC) for determination of interferon alpha(2a) (IFN α(2a)) in plasma samples for therapeutic drug monitoring. A restricted access material (RAM, protein-coated silica) was employed for preparation of a lab-made biocompatible in-tube SPME capillary that enables the direct injection of biological fluids as well as the simultaneous exclusion of macromolecules by chemical diffusion barrier and drug pre-concentration. The in-tube SPME variables, such as sample volume, draw/eject volume, number of draw-eject cycles, and desorption mode were optimized, to improve the sensitivity of the proposed method. The IFN α(2a) analyses in plasma sample were carried out within 25min (sample preparation and LC analyses). The response of the proposed method was linear over a dynamic range, from 0.06 to 3.0MIUmL(-1), with correlation coefficient equal to 0.998. The interday precision of the method presented coefficient of variation lower than 8%. The proposed automated method has adequate analytical sensitivity and selectivity for determination of IFN α(2a) in plasma samples for therapeutic drug monitoring. Copyright © 2010 Elsevier B.V. All rights reserved.

Plasma astrophysics

CERN Document Server

Kaplan, S A; ter Haar, D

2013-01-01

Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

NS3 protease resistance-associated substitutions in liver tissue and plasma samples from patients infected by hepatitis C virus genotype 1A or 1B.

Science.gov (United States)

Morsica, Giulia; Andolina, Andrea; Merli, Marco; Messina, Emanuela; Hasson, Hamid; Lazzarin, Adriano; Uberti-Foppa, Caterina; Bagaglio, Sabrina

2017-08-01

The presence of naturally occurring resistance-associated substitutions (RASs) in the HCV-protease domain has been poorly investigated in the liver, the main site of HCV replication. We evaluated the natural resistance of the virus to NS3 protease inhibitors in liver tissue and plasma samples taken from HCV-infected patients. RASs were investigated by means of viral population sequencing in liver tissue samples from 18 HCV-infected patients harbouring genotype 1a or genotype 1b; plasma samples from 12 of these patients were also available for virological investigation. A discordant genotype was found in two of the 12 patients (16.6%) who provided samples from both compartments. Sequence analysis of the NS3 protease domain showed the presence of RASs in four of the 18 liver tissue samples (22.2%), two of which showed cross-resistance to protease inhibitors in clinical use or phase 2-3 trials. The analysis of the 12 paired tissues and plasma samples excluded the presence of RASs in the plasma compartment. The dominance of discordant genotypes in the paired liver and plasma samples of some HCV-infected patients suggests mixed infection possibly leading to the selective advantage of different genotype in the two compartments. The presence of RASs at intra-hepatic level is not uncommon and may lead to the early emergence of cross-resistant strains.

Collective scattering of electromagnetic waves from a relativistic magnetized plasma

International Nuclear Information System (INIS)

Lu Quankang

1998-01-01

Recently, laser and microwave scattering has become one of the important diagnostic means for plasma. Laser and microwave correlative scattering spectrum is determined by particle-density fluctuations in a weak turbulent plasma. In a relativistic plasma, on the basis of complete electromagnetic-interaction between particles, a general expression for particle density fluctuations and spectrums of laser and microwave scattering from a magnetized plasma are derived. The laser and microwave scattering spectrums provide informations on electron density and temperature, ion temperature, resonance and nonresonance effects. (author)

Tamsulosin shows a higher unbound drug fraction in human prostate than in plasma: a basis for uroselectivity?

Science.gov (United States)

Korstanje, Cees; Krauwinkel, Walter; van Doesum-Wolters, Francisca L C

2011-01-01

AIM The aim of this small patient study was to investigate tamsulosin concentrations in prostate and plasma samples in order to identify potential differences in the pharmacokinetics (PK) in plasma and prostate contributing to its pharmacodynamic activity profile in patients. METHODS Forty-one patients with benign prostatic hyperplasia (BPH) scheduled for open prostatectomy were given tamsulosin 0.4 mg for 6–21 days in order to reach steady-state PK. Patients were randomized over four groups to allow collection of plasma and tissue samples at different time points after last dose administration. Samples were collected during surgery and assayed for tamsulosin HCl. The free fraction (fu) of tamsulosin was determined by ultracentrifugation of plasma and prostate tissue spiked with 14C-tamsulosin. RESULTS Cmax in plasma at 4.4 h for total tamsulosin was 15.2 ng ml−1 and AUC(0,24 h) was 282 ng ml−1 h, while for prostate Cmax at 11.4 h post-dose was 5.4 ng ml−1 and AUC(0,24 h) was 120 ng ml−1 h. AUC(0,24 h) for total tamsulosin in prostate was 43% of the plasma AUC(0,24 h). fu was 0.4 % for plasma and 59.1% for prostate. Therefore calculated on unbound tamsulosin, a ratio of 63 resulted for prostate vs. plasma Cmax concentrations. CONCLUSIONS These data indicate that in patients with confirmed BPH the amount of tamsulosin freely available in the target tissue (prostate) is much higher than in plasma. PMID:21745239

Plasma physics and fusion plasma electrodynamics

CERN Document Server

Bers, Abraham

2016-01-01

Plasma is a ubiquitous state of matter at high temperatures. The electrodynamics of plasmas encompasses a large number of applications, from understanding plasmas in space and the stars, to their use in processing semiconductors, and their role in controlled energy generation by nuclear fusion. This book covers collective and single particle dynamics of plasmas for fully ionized as well as partially ionized plasmas. Many aspects of plasma physics in current fusion energy generation research are addressed both in magnetic and inertial confinement plasmas. Linear and nonlinear dynamics in hydrodynamic and kinetic descriptions are offered, making both simple and complex aspects of the subject available in nearly every chapter. The approach of dividing the basic aspects of plasma physics as "linear, hydrodynamic descriptions" to be covered first because they are "easier", and postponing the "nonlinear and kinetic descriptions" for later because they are "difficult" is abandoned in this book. For teaching purpose...

Quantitative evaluation of plasma after methylene blue and white light treatment in four Chinese blood centers.

Science.gov (United States)

Chunhui, Yang; Guohui, Bian; Hong, Yang; Xiaopu, Xiao; Zherong, Bai; Mingyuan, Wang; Xinsheng, Zhang; Juanjuan, Wang; Changqing, Li; Wuping, Li

2013-12-01

Pathogen reduction technology is an important process in the blood safety system, including solvent/detergent treatment, filtration and methylene blue-photochemical technology (MB-PCT). To investigate the quality of MB-PCT-treated plasma, plasma samples from four Chinese blood centers were analyzed over 12 months of storage to determine the recovery of activities and levels of various plasma proteins. Ten plasma units each from the Suzhou, Yancheng, Chongqing and Shandong blood centers were divided into two aliquots. One was subjected to treatment with one of two methylene blue-photochemical technology instruments and the other was used as control. The treated and untreated sample pairs were stored at -30°C. The recovery rates of coagulation factors, inhibitor proteins, total protein, immunoglobulins, and complement proteins were measured at different time points after storage. The mean recovery of most proteins exceeded 80% after MB treatment. The exceptions were factor XI and fibrinogen, of which only 71.3-74% and 69.0-92.3% were retained during storage. The two equipment types differed in terms of residual MB concentration in the plasma samples (0.18 μM and 0.29 μM, respectively). They had similar protein recovery rates at 0.5 month but differed at later time points. The four blood centers differed significantly with regard to factor II, V, VIII and fibrinogen activities. Only the samples from the Shandong blood center met the methylene blue treated fresh frozen plasma requirement. The major factor that influenced the quality of the MB-FFP samples was the time taken between blood collection and storage. Methylene blue treated plasma showed reduced coagulation factor (CF) activity and protein levels. The MB treatment-induced damage to the proteins was acceptable at the four Chinese blood centers, but the quality of the MB-treated plasma in general was not satisfactory. The main factor affecting plasma quality may be the duration of the collection and

Use of self-collected capillary blood samples for islet autoantibody screening in relatives: a feasibility and acceptability study.

Science.gov (United States)

Liu, Y; Rafkin, L E; Matheson, D; Henderson, C; Boulware, D; Besser, R E J; Ferrara, C; Yu, L; Steck, A K; Bingley, P J

2017-07-01

To evaluate the feasibility of using self-collected capillary blood samples for islet autoantibody testing to identify risk in relatives of people with Type 1 diabetes. Participants were recruited via the observational TrialNet Pathway to Prevention study, which screens and monitors relatives of people with Type 1 diabetes for islet autoantibodies. Relatives were sent kits for capillary blood collection, with written instructions, an online instructional video link and a questionnaire. Sera from capillary blood samples were tested for autoantibodies to glutamic acid decarboxylase, islet antigen-2, insulin and zinc transporter 8. 'Successful' sample collection was defined as obtaining sufficient volume and quality to provide definitive autoantibody results, including confirmation of positive results by repeat assay. In 240 relatives who returned samples, the median (range) age was 15.5 (1-49) years and 51% were male. Of these samples, 98% were sufficient for glutamic acid decarboxylase, islet antigen-2 and zinc transporter 8 autoantibody testing and 84% for insulin autoantibody testing and complete autoantibody screen. The upper 90% confidence bound for unsuccessful collection was 4.4% for glutamic acid decarboxylase, islet antigen-2 and/or zinc transporter 8 autoantibody assays, and 19.3% for insulin autoantibodies. Despite 43% of 220 questionnaire respondents finding capillary blood collection uncomfortable or painful, 82% preferred home self-collection of capillary blood samples compared with outpatient venepuncture (90% of those aged 18 years). The perceived difficulty of collecting capillary blood samples did not affect success rate. Self-collected capillary blood sampling offers a feasible alternative to venous sampling, with the potential to facilitate autoantibody screening for Type 1 diabetes risk. © 2017 Diabetes UK.

New Zealand guidelines for the collection of groundwater samples for chemical and isotopic analyses

International Nuclear Information System (INIS)

Rosen, M.R.; Cameron, S.G.; Reeves, R.R.; Taylor, C.B.

1999-01-01

Chemical and isotopic analyses of groundwater are important tools for differentiating between the natural composition and human-induced contaminants of groundwater. A comprehensive suite of inorganic water chemical analyses is necessary to characterise waters. The geology of New Zealand is diverse, so it is impractical to characterise a ''typical'' groundwater chemical composition. Each aquifer system should be evaluated individually because the major dissolved species contain useful information about the pathways of water through the soil zone into the aquifer. Analyses of major ions such as chloride, nitrate, potassium and sulphate often give indication of septic systems and agricultural contamination. The minor ions, while most are not considered contaminants, are often indicators of human activity. Iron and manganese are good indicators of Eh potential, which is an important control on the mobility of many heavy metals. The inexpensive inorganic chemical analytical suite should be used as a guide to advisability of more expensive contaminant testing. The purpose of this manual is to provide consistent groundwater sampling guidelines for use throughout New Zealand. Sinton's (1998) guide to groundwater sampling techniques provided a sound basis for the accurate collection of groundwater samples. However Sinton did not address sampling materials and techniques for the collection of samples for ultra trace component analysis or the collection of environmental isotope samples. These important aspects of groundwater sampling have been included in this updated manual. (author). 30 refs., 12 figs., 5 tabs., 1 appendix

Kinetics of HIV-1 in cerebrospinal fluid and plasma in cryptococcal meningitis

Directory of Open Access Journals (Sweden)

Jorge A. Benetucci

2012-04-01

Full Text Available In order to determine HIV-1 kinetics in cerebrospinal fluid (CSF and plasma in patients with cryptococcal meningitis (CM, we undertook a prospective collection of paired CSF/plasma samples from antiretroviral therapy- free HIV-infected patients with CM. Samples were obtained at baseline (S1 and at the second (S2 and third (S3 weeks of antifungal therapy. HIV-1 CSF concentrations were significantly lower in both S2 and S3 with respect to S1. Plasma concentrations remained stable. HIV-1 concentrations were higher in plasma than CSF in all cases. Patients who survived the episode of CM (but not those who died showed a decrease in CSF viral load, what suggests different viral kinetics of HIV-1 in the CSF according to the clinical course of this opportunistic disease.

Assessment of changes in plasma hemoglobin and potassium levels in red cell units during processing and storage.

Science.gov (United States)

Saini, Nishant; Basu, Sabita; Kaur, Ravneet; Kaur, Jasbinder

2015-06-01

Red cell units undergo changes during storage and processing. The study was planned to assess plasma potassium, plasma hemoglobin, percentage hemolysis during storage and to determine the effects of outdoor blood collection and processing on those parameters. Blood collection in three types of blood storage bags was done - single CPDA bag (40 outdoor and 40 in-house collection), triple CPD + SAGM bag (40 in-house collection) and quadruple CPD + SAGM bag with integral leukoreduction filter (40 in-house collection). All bags were sampled on day 0 (day of collection), day 1 (after processing), day 7, day 14 and day 28 for measurement of percentage hemolysis and potassium levels in the plasma of bag contents. There was significant increase in percentage hemolysis, plasma hemoglobin and plasma potassium level in all the groups during storage (p levels during the storage of red blood cells. Blood collection can be safely undertaken in outdoor blood donation camps even in hot summer months in monitored blood transport boxes. SAGM additive solution decreases the red cell hemolysis and allows extended storage of red cells. Prestorage leukoreduction decreases the red cell hemolysis and improves the quality of blood. Copyright © 2015 Elsevier Ltd. All rights reserved.

Analysis of Samples Collected from the Surface of Interim Storage Canisters at Calvert Cliffs in June 2017: Revision 01.

Energy Technology Data Exchange (ETDEWEB)

Bryan, Charles R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schindelholz, Eric John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-11-01

In June 2017, dust and salt samples were collected from the surface of Spent Nuclear Fuel (SNF) dry storage canisters at the Calvert Cliffs Nuclear Power Plant. The samples were delivered to Sandia National laboratories for analysis. Two types of samples were collected: filter-backed Scotch-Brite TM pads were used to collect dry dust samples for characterization of salt and dust morphologies and distributions; and Saltsmart TM test strips were used to collect soluble salts for determining salt surface loadings per unit area. After collection, the samples were sealed into plastic sleeves for shipping. Condensation within the sleeves containing the Scotch-Brite TM samples remobilized the salts, rendering them ineffective for the intended purpose, and also led to mold growth, further compromising the samples; for these reasons, the samples were not analyzed. The SaltSmart TM samples were unaffected and were analyzed by ion chromatography for major anions and cations. The results of those analyses are presented here.

Collection and preparation of marine samples for radionuclide analysis

International Nuclear Information System (INIS)

Holm, E.

1997-01-01

The ultimate goal of research in radioecology is to be able to predict the pathways of radioactive material in the environment and hence estimate possible doses to the population in various regions. Knowledge of levels of contamination are necessary to maintain control of operations of nuclear facilities. Correct methods of sample collection, handling and preparation are among the most important parts for a correct assessment. On basis of the final results of radionuclide concentrations, scientific, medical and political decisions are taken. (author)

A simple and novel method for retrieval of Pasteurellaceae from swab samples collected in the field

DEFF Research Database (Denmark)

Hansen, Mie J; Bertelsen, Mads F; Dietz, Rune

2013-01-01

and stored at -20°C. As a control study, 15 samples were collected from the oral cavity of a captive brown bear. One was immediately plated, while the remaining 12 swabs were stored at -20°C for 7 days and multiples of 30 days up to 330 days prior to plating. Two samples were stored without the medium for 7......Traditionally it has been difficult or impossible to collect and preserve bacterial samples of especially fastidious bacteria in mixed primary cultures, unless the samples could be transported to a laboratory within approximately 24 h. Therefore, a simple novel method for preserving swab samples...... until bacterial isolation can be completed in the laboratory was developed and evaluated. Pasteurellaceae bacteria were used as a representative for fastidious bacteria. A 7.5% glucose serum medium was used as freeze medium. Swab samples were soaked in the medium a maximum of 2 h after collection...

Radioimmunoassay for male canine plasma 4-androstenedione, testosterone and 5α-dihydrotestosterone

International Nuclear Information System (INIS)

Inaba, Toshio; Shimizu, Ryosuke; Imori, Tatsuo

1977-01-01

The radioimmunoassay for the simultaneous measurement of 4-androstenedione (A), testosterone (T), and 5α-dihydrotestosterone (DHT) in canine plasma was carried out. The assay for these 3 plasma steroids showed to be satisfactorily sensitive, specific, and accurate. The plasma steroid levels of peripheral and spermary vein plasma collected from 15 male dogs were (A) 0.86 +-0.75, (T) 1.19+-1.05 and (DHT) 0.30+-0.25 in peripheral vein, and (A) 30.2+-18.5, (T) 157+-98 and (DHT) 17.5+-10.7 in spermary vein, respectively (ng/ml and SD). Analysing these data, the significant correlation between two vein plasma levels was suggested. In order to estimate the normal or common diurnal variations of these plasma steroid levels in male dogs, 5 animals were employed, and their peripheral plasma samples were collected every an hour or two, throughout 24 hour period. In these data, the frequent intermittent peaks of plasma steroids were observed in each dog, and these seem to be their own diurnal changes. It was concluded that the peripheral plasma levels of A, T, and DHT were correlated to those in spermary vein, and these steroid levels were seemingly reflected by the episodic secretion from the gonads. (Kobatake, H.)

Multielement determination of rare earth elements in rock sample by liquid chromatography / inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Hamanaka, Tadashi; Itoh, Akihide; Itoh, Shinya; Sawatari, Hideyuki; Haraguchi, Hiroki.

1995-01-01

Rare earth elements in geological standard rock sample JG-1 (granodiolite)issued from the Geological Survey of Japan have been determined by a combined system of liquid chromatography and inductively coupled plasma mass spectrometry. (author)

Procedures for the collection and preservation of groundwater and surface water samples and for the installation of monitoring wells

International Nuclear Information System (INIS)

Korte, N.; Kearl, P.

1984-01-01

Proper sampling procedures are essential for a successful water-quality monitoring program. It must be emphasized, however, that it is impossible to maintain absolutely in-situ conditions when collecting and preserving a water sample, whether from a flowing stream or an aquifer. Consequently, the most that can reasonably be expected is to collect a best possible sample with minimal disturbance. This document describes procedures for installing monitoring wells and for collecting samples of surface water and groundwater. The discussion of monitoring wells includes mention of multilevel sampling and a general overview of vadose-zone monitoring. Guidelines for well installation are presented in detail. The discussion of water-sample collection contains evaluations of sampling pumps, filtration equipment, and sample containers. Sample-preservation techniques, as published by several government and private sources, are reviewed. Finally, step-by-step procedures for collection of water samples are provided; these procedures address such considerations as necessary equipment, field operations, and written documentation. Separate procedures are also included for the collection of samples for determination of sulfide and for reactive aluminum. The report concludes with a brief discussion of adverse sampling, conditions that may significantly affect the quality of the data. Appendix A presents a rationale for the development and use of statistical considerations in water sampling to ensure a more complete water quality monitoring program. 51 references, 9 figures, 4 tables

Surface resistivity measurement of plasma treated polymers

International Nuclear Information System (INIS)

Simon, D.; Pigram, P.J.; Liesegang, J.

2000-01-01

Full text: Resistivity of insulators is an important property of materials used within the integrated circuit and packaging industries. The measurement of electrical resistivity of insulator materials in the surface region in this work is interpreted through observations of surface charge decay. A self-field driven and diffusion charge transport theory is used to model the process and resistivity values obtained computationally. Data for the charge decay of surface charged samples are collected by suspending them inside a coaxial cylinder connected to an electrometer. Samples used have been low density polyethylene LDPE sheet, both pristine and surface treated. Some samples have been treated by air plasma at low vacuum pressures for different periods of time; others have been washed in ethyl acetate and then plasma treated before the resistivity measurement. The sets of resistivity measurements form the various treatments are compared below. X-ray photoelectron spectroscopy (XPS) has also been used to investigate and account for the observed variations in surface resistivity

Multi-element composition of historical lichen collections and bark samples, indicators of changing atmospheric conditions

Science.gov (United States)

Purvis, O. W.; Chimonides, P. D. J.; Jeffries, T. E.; Jones, G. C.; Rusu, A.-M.; Read, H.

Thirty six element signatures were compared in historical Parmelia sulcata samples from the Natural History Museum herbarium collected over the period 1797-1967 with those recorded in the same species and tree bark sampled in 2000 from Burnham Beeches, lying 40 km west of London. Nineteen elements reached highest concentrations in herbarium samples, consistent with a pollution legacy and dust contamination in the herbarium. Healthy Parmelia sampled east and down-wind of London at a farm during peak SO 2 emissions in 1967 contained highest V, Ni, Zn, Cd, Se, Ge contents, supporting derivation from fuel combustion; the same sample was previously determined as having a low δ34S and high S and N contents. Lowest V, Co, Ni, Cu, Zn, Sn, Ba, Pb, Mo, Sb, Li, B, Cs, U, Th, Ga contents were recorded in a sample with a high δ34S and low S content collected in 1887 from a remote region from Ross-shire, Scotland. Se and Cd enrichment, never-the-less suggest a transboundary pollution influence. Lichen Pb concentrations from Burnham Beeches were amongst the lowest recorded in spite of lichens being collected close to roads. Herbarium samples help interpret changes in element deposition where few data exist, in spite of dust contamination.

Determination of 90Sr and Pu isotopes in contaminated groundwater samples by inductively coupled plasma mass spectrometry

Science.gov (United States)

Zoriy, Miroslav V.; Ostapczuk, Peter; Halicz, Ludwik; Hille, Ralf; Becker, J. Sabine

2005-04-01

A sensitive analytical method for determining the artificial radionuclides 90Sr, 239Pu and 240Pu at the ultratrace level in groundwater samples from the Semipalatinsk Test Site area in Kazakhstan by double-focusing sector field inductively coupled plasma mass spectrometry (ICP-SFMS) was developed. In order to avoid possible isobaric interferences at m/z 90 for 90Sr determination (e.g. 90Zr+, 40Ar50Cr+, 36Ar54Fe+, 58Ni16O2+, 180Hf2+, etc.), the measurements were performed at medium mass resolution under cold plasma conditions. Pu was separated from uranium by means of extraction chromatography using Eichrom TEVA resin with a recovery of 83%. The limits of detection for 90Sr, 239Pu and 240Pu in water samples were determined as 11, 0.12 and 0.1 fg ml-1, respectively. Concentrations of 90Sr and 239Pu in contaminated groundwater samples ranged from 18 to 32 and from 28 to 856 fg ml-1, respectively. The 240Pu/239Pu isotopic ratio in groundwater samples was measured as 0.17. This isotope ratio indicates that the most probable source of contamination of the investigated groundwater samples was the nuclear weapons tests at the Semipalatinsk Test Site conducted by the USSR in the 1960s.

Application of XRF methods for multielemental analysis of lichen samples collected in Havana City. Comparison with ICP-AES, ICP-MS and FAAS

International Nuclear Information System (INIS)

Herrero Fernandez, Zahily; Estevez Alvarez, Juan R.; Montero Alvarez, Alfredo; Pupo Gonzalez, Ivan; Ortueta Milan, Marvic; Mesa Perez, Guillermo; Leyva Bombuse, Dennys; Rodriguez Gonzalez, Maydel; Hernandez Torres, Debora; Padilla Alvarez, Roman; Quejido Cabezas, Alberto J.; Rucandio Saez, Maria I.; Fernandez Diaz, Marta

2011-01-01

This paper presents the results of the analysis of Ca, Fe, Zn, Br, Rb, Sr and Pb in samples of lichens used as biomonitors of air pollution collecting in Havana City during 2009-2010. Two different X-Ray Fluorescence methods were used. First, a combination of Si (Li) detector with an annular 109Cd as primary excitation source was employed. The second system consisted in a Mo X-ray tube with a secondary target of Molybdenum and a X-PIPS detector. In both configurations, the correction of matrix effects was achieved by using the Compton scattering peak. The quantification was performed using calibration curves obtained from different biological Certified Reference Materials. The determination of elements by Inductively Coupled Plasma-Atomic Emission Spectrometry, Inductively Coupled Plasma-Mass Spectrometry and Flame Atomic Absorption Spectrophotometry was carried out in order to evaluate the reliability of XRF methods. No significant differences were found between the obtained results by the different techniques. The levels of concentration of the analyzed elements in the lichens in 2009 and 2010 respectively were similar. The elemental distribution patters obtained for each metal were associated with different sources of contamination. (Author)

Impaired plasma lipid profiles in acute hepatitis

Directory of Open Access Journals (Sweden)

Wang Yongzhong

2010-01-01

Full Text Available Abstract The present study examined plasma lipid profiles in thirty patients suffered from acute viral hepatitis. Patients' blood samples were collected at both the debut and recovery of diseases. Thirty sex and age matched normal subjects were included as controls. Plasma total triglycerides (TG, total cholesterol, high density lipoprotein cholesterol (HDL-C, low density lipoprotein cholesterol (LDL-C, apolipoprotein AI (ApoAI, apolipoprotein B (ApoB, lipoprotein (a (Lp(a, blood coagulation status including prothrombin complex activity and activated partial tromboplastin time (APTT, and hepatic functions were determined by the automatic biochemical analytical instrument. It demonstrated that plasma levels of total cholesterol, HDL-C and apoAI were significantly lower in the patients at the acute phase of hepatitis than those in normal subjects, whereas plasma levels of TG and LDL-C were obviously higher in the patients than in normal subjects (P

K-shell photoionizations in classical nonideal plasmas

International Nuclear Information System (INIS)

Jung, Young-Dae

2001-01-01

Collective and plasma screening effects on photoionization cross sections from the 1s state of hydrogenic ions in classical nonideal plasmas are investigated. An effective pseudopotential model taking into account the collective and plasma screening effects is applied to describe the interaction potential in nonideal plasmas. The screened atomic wave function and energy eigenvalue for the ground state of the hydrogenic ion in classical nonideal plasmas are obtained by the Ritz variational method. The photoionization cross section is obtained by the acceleration form of the transition matrix element in order to investigate the collective and plasma screening effects on the interaction potential. The retardation and Coulomb correction effects are also considered in nonideal plasmas. The total correlation effect is obtained as a function of the nonideality plasma parameter, Debye length, and incident photon energy. The result shows that the collective effect significantly reduces the photoionization cross section. It is also found that the collective effect on the photoionization cross section is increased with increasing the incident photon energy

Control of the positional relationship between a sample collection instrument and a surface to be analyzed during a sampling procedure using a laser sensor

Science.gov (United States)

Van Berkel, Gary J [Clinton, TN; Kertesz, Vilmos [Knoxville, TN

2012-02-21

A system and method utilizes distance-measuring equipment including a laser sensor for controlling the collection instrument-to-surface distance during a sample collection process for use, for example, with mass spectrometric detection. The laser sensor is arranged in a fixed positional relationship with the collection instrument, and a signal is generated by way of the laser sensor which corresponds to the actual distance between the laser sensor and the surface. The actual distance between the laser sensor and the surface is compared to a target distance between the laser sensor and the surface when the collection instrument is arranged at a desired distance from the surface for sample collecting purposes, and adjustments are made, if necessary, so that the actual distance approaches the target distance.

Acceptability of self-collected vaginal samples for HPV testing in an ...

African Journals Online (AJOL)

Objective: To evaluate the acceptability of self-collected vaginal samples for HPV testing in women living in rural and urban areas of Madagascar. Materials and methods: Participants were recruited in a health care center (urban group) and smaller affiliated dispensaries (rural group). They were invited to perform ...

Design of a scanning probe microscope with advanced sample treatment capabilities: An atomic force microscope combined with a miniaturized inductively coupled plasma source

International Nuclear Information System (INIS)

Hund, Markus; Herold, Hans

2007-01-01

We describe the design and performance of an atomic force microscope (AFM) combined with a miniaturized inductively coupled plasma source working at a radio frequency of 27.12 MHz. State-of-the-art scanning probe microscopes (SPMs) have limited in situ sample treatment capabilities. Aggressive treatments such as plasma etching or harsh treatments such as etching in aggressive liquids typically require the removal of the sample from the microscope. Consequently, time consuming procedures are required if the same sample spot has to be imaged after successive processing steps. We have developed a first prototype of a SPM which features a quasi in situ sample treatment using a modified commercial atomic force microscope. A sample holder is positioned in a special reactor chamber; the AFM tip can be retracted by several millimeters so that the chamber can be closed for a treatment procedure. Most importantly, after the treatment, the tip is moved back to the sample with a lateral drift per process step in the 20 nm regime. The performance of the prototype is characterized by consecutive plasma etching of a nanostructured polymer film

Plasma Immersion Ion Implantation in Radio Frequency Plasma

International Nuclear Information System (INIS)

Bora, B.; Bhuyan, H.; Wyndham, E.

2013-01-01

Plasma immersion ion implantation (PIII) has attracted wide interests since it emulates conventional ion-beam ion implantation (IBII) in niche applications. For instance, the technique has very high throughput, the implantation time is independent of the sample size, and samples with an irregular shape can be implanted without complex beam scanning or sample manipulation. For uniform ion implantation and deposition on to different substrates, like silicon, stainless steel etc., a capacitive coupled Radio frequency (RF), 13.6 MHz, plasma is used. During the PIII process, the physical parameters which are expected to play crucial rule in the deposition process like RF power, Negative pulse voltage and pulse duration, gas type and gas mixture, gas flow rates and the implantation dose are studied. The ion dose is calculated by dynamic sheath model and the plasma parameters are calculated from the V-I characteristic and power balance equation by homogeneous model of rf plasma discharge considering Ohmic as well as Stochastic heating. The correlations between the yield of the implantation process and the physical parameters as well as plasma parameters are discussed. (author)

CTEPP STANDARD OPERATING PROCEDURE FOR COLLECTION OF SOIL SAMPLES FOR PERSISTENT ORGANIC POLLUTANTS (SOP-2.20)

Science.gov (United States)

This SOP describes the method for collecting soil samples from the child's outdoor play area to measure for persistent organic pollutants. Soil samples are collected by scraping up the top 0.5 cm of soil in a 0.095 m2 (1 ft2) area in the middle of the child's play area.

Chlamydia trachomatis antibody detection in home-collected blood samples for use in epidemiological studies.

NARCIS (Netherlands)

Hoenderboom, B M; van Ess, E F; van den Broek, I V F; van Loo, I H M; Hoebe, C J P A; Ouburg, S; Morré, S A

Capillary blood collected in serum tubes was subjected to centrifugation delay while stored at room temperature. Chlamydia trachomatis (CT) IgG concentrations in aliquoted serum of these blood samples remained stable for seven days after collection. CT IgG concentrations can reliably be measured in

A new Langmuir probe concept for rapid sampling of space plasma electron density

International Nuclear Information System (INIS)

Jacobsen, K S; Pedersen, A; Moen, J I; Bekkeng, T A

2010-01-01

In this paper we describe a new Langmuir probe concept that was invented for the in situ investigation of HF radar backscatter irregularities, with the capability to measure absolute electron density at a resolution sufficient to resolve the finest conceivable structure in an ionospheric plasma. The instrument consists of two or more fixed-bias cylindrical Langmuir probes whose radius is small compared to the Debye length. With this configuration, it is possible to acquire absolute electron density measurements independent of electron temperature and rocket/satellite potential. The system was flown on the ICI-2 sounding rocket to investigate the plasma irregularities which cause HF backscatter. It had a sampling rate of more than 5 kHz and successfully measured structures down to the scale of one electron gyro radius. The system can easily be adapted for any ionospheric rocket or satellite, and provides high-quality measurements of electron density at any desired resolution

Improved explosive collection and detection with rationally assembled surface sampling materials

Energy Technology Data Exchange (ETDEWEB)

Chouyyok, Wilaiwan; Bays, J. Timothy; Gerasimenko, Aleksandr A.; Cinson, Anthony D.; Ewing, Robert G.; Atkinson, David A.; Addleman, R. Shane

2016-01-01

Sampling and detection of trace explosives is a key analytical process in modern transportation safety. In this work we have explored some of the fundamental analytical processes for collection and detection of trace level explosive on surfaces with the most widely utilized system, thermal desorption IMS. The performance of the standard muslin swipe material was compared with chemically modified fiberglass cloth. The fiberglass surface was modified to include phenyl functional groups. When compared to standard muslin, the phenyl functionalized fiberglass sampling material showed better analyte release from the sampling material as well as improved response and repeatability from multiple uses of the same swipe. The improved sample release of the functionalized fiberglass swipes resulted in a significant increase in sensitivity. Various physical and chemical properties were systematically explored to determine optimal performance. The results herein have relevance to improving the detection of other explosive compounds and potentially to a wide range of other chemical sampling and field detection challenges.

Plasma characterization using ultraviolet Thomson scattering from ion-acoustic and electron plasma waves (invited)

Energy Technology Data Exchange (ETDEWEB)

Follett, R. K., E-mail: rfollett@lle.rochester.edu; Delettrez, J. A.; Edgell, D. H.; Henchen, R. J.; Katz, J.; Myatt, J. F.; Froula, D. H. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 (United States)

2016-11-15

Collective Thomson scattering is a technique for measuring the plasma conditions in laser-plasma experiments. Simultaneous measurements of ion-acoustic and electron plasma-wave spectra were obtained using a 263.25-nm Thomson-scattering probe beam. A fully reflective collection system was used to record light scattered from electron plasma waves at electron densities greater than 10{sup 21} cm{sup −3}, which produced scattering peaks near 200 nm. An accurate analysis of the experimental Thomson-scattering spectra required accounting for plasma gradients, instrument sensitivity, optical effects, and background radiation. Practical techniques for including these effects when fitting Thomson-scattering spectra are presented and applied to the measured spectra to show the improvements in plasma characterization.

Sample collection of virulent and non-virulent B. anthracis and Y. pestis for bioforensics analysis

Energy Technology Data Exchange (ETDEWEB)

Hong-geller, Elizabeth [Los Alamos National Laboratory; Valdez, Yolanda E [Los Alamos National Laboratory; Shou, Yulin [Los Alamos National Laboratory; Yoshida, Thomas M [Los Alamos National Laboratory; Marrone, Babetta L [Los Alamos National Laboratory; Dunbar, John [Los Alamos National Laboratory

2009-01-01

Validated sample collection methods are needed for recovery of microbial evidence in the event of accidental or intentional release of biological agents into the environment. To address this need, we evaluated the sample recovery efficiencies of two collection methods -- swabs and wipes -- for both non-virulent and virulent strains of B. anthracis and Y. pestis from four types of non-porous surfaces: two hydrophilic surfaces, stainless steel and glass, and two hydrophobic surfaces, vinyl and plastic. Sample recovery was quantified using Real-time qPCR to assay for intact DNA signatures. We found no consistent difference in collection efficiency between swabs or wipes. Furthermore, collection efficiency was more surface-dependent for virulent strains than non-virulent strains. For the two non-virulent strains, B. anthracis Sterne and Y. pestis A1122, collection efficiency was approximately 100% and 1 %, respectively, from all four surfaces. In contrast, recovery of B. anthracis Ames spores and Y. pestis C092 from vinyl and plastic was generally lower compared to collection from glass or stainless steel, suggesting that surface hydrophobicity may playa role in the strength of pathogen adhesion. The surface-dependent collection efficiencies observed with the virulent strains may arise from strain-specific expression of capsular material or other cell surface receptors that alter cell adhesion to specific surfaces. These findings contribute to validation of standard bioforensics procedures and emphasize the importance of specific strain and surface interactions in pathogen detection.

PFAS concentrations in plasma samples from Danish school children and their mothers.

Science.gov (United States)

Mørck, Thit A; Nielsen, Flemming; Nielsen, Jeanette K S; Siersma, Volkert D; Grandjean, Philippe; Knudsen, Lisbeth E

2015-06-01

Perfluoroalkyl substances (PFASs) are accumulating in our environment and human exposure to these potentially harmful chemicals are of growing concern. In the present study, 116 children aged 6-11 and 143 mothers in two locations in Denmark donated blood samples as a supplement to their participation in the large European human biomonitoring project, DEMOCOPHES (Demonstration of a study to COordinate and Perform Human Biomonitoring on a European Scale). The blood samples were analyzed by LC-MS/MS for the concentration of six PFASs: PFOA, PFHxS, PFNA, PFDA, br-PFOS and n-PFOS. All measured compounds were above the detection limit in both mothers and children except for PFHxS in one child. There was a significant correlation between the levels in children and their mothers, indicating a family-related exposure pattern. However, we also found that the levels of PFOA, PFNA, PFDA, br-PFOS and total-PFOS were significantly higher in children compared to their mothers. This may be due to higher exposure in children through for example dust and soil, and due to the fact that children are smaller in body size and blood volume and hence have a lower storage capacity. Furthermore, we found an association between plasma levels and the age of the mothers and higher levels of plasma PFASs in mothers with low parity. There were no associations between PFAS concentrations and residential area, dietary habits of the participants or with respect to the birth order of the children. The levels are comparable to concentrations found in other Western countries. Copyright © 2014 Elsevier Ltd. All rights reserved.

21 CFR 809.40 - Restrictions on the sale, distribution, and use of OTC test sample collection systems for drugs...

Science.gov (United States)

2010-04-01

... OTC test sample collection systems for drugs of abuse testing. 809.40 Section 809.40 Food and Drugs... Restrictions on the sale, distribution, and use of OTC test sample collection systems for drugs of abuse testing. (a) Over-the-counter (OTC) test sample collection systems for drugs of abuse testing (§ 864.3260...

Normalisation of spot urine samples to 24-h collection for assessment of exposure to uranium

International Nuclear Information System (INIS)

Marco, R.; Katorza, E.; Gonen, R.; German, U.; Tshuva, A.; Pelled, O.; Paz-tal, O.; Adout, A.; Karpas, Z.

2008-01-01

For dose assessment of workers at Nuclear Research Center Negev exposed to natural uranium, spot urine samples are analysed and the results are normalised to 24-h urine excretion based on 'standard' man urine volume of 1.6 l d -1 . In the present work, the urine volume, uranium level and creatinine concentration were determined in two or three 24-h urine collections from 133 male workers (319 samples) and 33 female workers (88 samples). Three volunteers provided urine spot samples from each voiding during a 24-h period and a good correlation was found between the relative level of creatinine and uranium in spot samples collected from the same individual. The results show that normalisation of uranium concentration to creatinine in a spot sample represents the 24-h content of uranium better than normalisation to the standard volume and may be used to reduce the uncertainty of dose assessment based on spot samples. (authors)

Optical plasma torch electron bunch generation in plasma wakefield accelerators

Directory of Open Access Journals (Sweden)

G. Wittig

2015-08-01

Full Text Available A novel, flexible method of witness electron bunch generation in plasma wakefield accelerators is described. A quasistationary plasma region is ignited by a focused laser pulse prior to the arrival of the plasma wave. This localized, shapeable optical plasma torch causes a strong distortion of the plasma blowout during passage of the electron driver bunch, leading to collective alteration of plasma electron trajectories and to controlled injection. This optically steered injection is more flexible and faster when compared to hydrodynamically controlled gas density transition injection methods.

Phenotype-Driven Plasma Biobanking Strategies and Methods

Directory of Open Access Journals (Sweden)

Erica A. Bowton

2015-05-01

Full Text Available Biobank development and integration with clinical data from electronic medical record (EMR databases have enabled recent strides in genomic research and personalized medicine. BioVU, Vanderbilt’s DNA biorepository linked to de-identified clinical EMRs, has proven fruitful in its capacity to extensively appeal to numerous areas of biomedical and clinical research, supporting the discovery of genotype-phenotype interactions. Expanding on experiences in BioVU creation and development, we have recently embarked on a parallel effort to collect plasma in addition to DNA from blood specimens leftover after routine clinical testing at Vanderbilt. This initiative offers expanded utility of BioVU by combining proteomic and metabolomic approaches with genomics and/or clinical outcomes, widening the breadth for potential research and subsequent future impact on clinical care. Here, we describe the considerations and components involved in implementing a plasma biobank program from a feasibility assessment through pilot sample collection.

Microparticle counts in platelet-rich and platelet-free plasma, effect of centrifugation and sample-processing protocols.

Science.gov (United States)

Chandler, Wayne L

2013-03-01

This study provides the first estimates of microparticle numbers in platelet-rich plasma (PRP) from normal individuals, closer to in-vivo levels, using higher-resolution flow cytometry. We measured platelet (CD41+) and annexin V+ microparticles in fresh and frozen aliquots of PRP, platelet-poor plasma, platelet-free plasma (PFP), and microparticles isolated by high-speed centrifugation. PRP from healthy individuals contained 730,000/μl total microparticles based on light-scattering measurements. A median of 27,000/μl microparticles in PRP were of platelet origin and 120,000/μl annexin V+, and of these, 24,000/μl were dual-positive procoagulant platelet microparticles. Double centrifugation of PRP removed 99% of platelets, but also 80% of annexin V+ CD41+, 93% of annexin V+ CD41-, and 58% of annexin V- CD41+ microparticles. Loss of microparticles with centrifugation varied from individual to individual. Microparticle counts after isolation by centrifugation and double washing were not significantly different than counts in the original PFP sample, but lower than in PRP. Freeze-thawing of PFP had no effect on platelet microparticle counts, but slightly increased annexin V+, CD41- counts. Freeze-thawing of isolated washed microparticles resulted in a 30-50% increase in annexin V+ microparticles. PRP contains large numbers of cellular microparticles, including platelet and annexin V+ microparticles, which are lost to varying degrees when PRP is double centrifuged to remove platelets. Microparticles remaining in PFP can be recovered by high-speed centrifugation without loss compared to the original PFP sample. Freeze-thawing has variable effects on microparticle counts depending on the sample preparation used.

BOVINE PLASMA FIBRINOGEN AS MARKER IN CLINICAL AND SUB-CLINICAL MASTITIS

Directory of Open Access Journals (Sweden)

R. Ali

2018-06-01

Full Text Available Plasma samples were collected from healthy as well as clinical and sub-clinical mastitis affected cows from Barasat, West Bengal, India. Plasma samples, after ammonium sulphate precipitation, were dialyzed against several changes of PBS (pH 7.2 to remove the excess ammonium sulphate. Then plasma fibrinogens were purified by gel filtration chromatography on Sephacryl S-200 HR. SDS-PAGE (10% of purified fibrinogen from plasma of healthy cow revealed polypeptide bands of 74, 67 and 57 kDa which represent the α (alpha, β (beta and γ (gamma- chains respectively. On the other hand, purified fibrinogen from plasma of sub-clinical and clinical mastitis affected cow revealed polypeptide bands of 73 (α-chain, 68 kDa (β-chain and 72 (γ-chain, 68 kDa (β-chain respectively. The SDS-PAGE analysis showed the absence of gamma (γ- chain of fibrinogen in both the samples of sub-clinical and clinical mastitis positive cow. Single precipitin line was observed in double immunodiffusion test when purified fibrinogen from healthy, clinical and subclinical mastitis positive cows reacted with hyper immune sera raised in rabbit. No precipitin line was found against the normal control serum. These purified fibrinogens also showed cross reactivity against antibody raised in rabbit when analyzed by western blot technique.

Collective scattering of electromagnetic waves and cross-B plasma diffusion

International Nuclear Information System (INIS)

Gresillon, D.; Cabrit, B.; Truc, A.

1992-01-01

Magnetized plasmas occuring in nature as well as in fusion laboratories are oftenly irregularly shaked by magnetic field fluctuations. The so-called ''coherent scattering'' of electromagnetic wave from nonuniform, irregularly moving plasmas is investigated in the case where the scattering wavelength is large compared to the Debye length, but of the order of the irregularities correlation length. The scattered signal frequency spectrum is shown to be a transform of the plasma motion statistical characteristics. When the scattering wavelength is larger than the plasma motion correlation length, the frequency spectrum is shown to be of a lorentzian shape, with a frequency width that provides a direct measurement of the cross-B particle diffusion coefficient. This is illustrated by two series of recently obtained experimental results: radar coherent backscattering observations of the auroral plasma, and far infrared scattering from tokamak fusion plasma. Radar coherent backscattering shows the transition from Gauss to Lorentz scattered frequency spectra. In infrared Laser coherent scattering experiments from the Tore-Supra tokamak, a particular frequency line is observed to present a Lorentzian shape, that directly provides an electron cross-field diffusion coefficient. This diffusion coefficient agrees with the electron heat conductivity coefficient that is obtained from the observation of temperature profiles and energy balance. (Author)

Planning Considerations Related to Collecting and Analyzing Samples of the Martian Soils

Science.gov (United States)

Liu, Yang; Mellon, Mike T.; Ming, Douglas W.; Morris, Richard V.; Noble, Sarah K.; Sullivan, Robert J.; Taylor, Lawrence A.; Beaty, David W.

2014-01-01

The Mars Sample Return (MSR) End-to-End International Science Analysis Group (E2E-iSAG [1]) established scientific objectives associ-ated with Mars returned-sample science that require the return and investigation of one or more soil samples. Soil is defined here as loose, unconsolidated materials with no implication for the presence or absence of or-ganic components. The proposed Mars 2020 (M-2020) rover is likely to collect and cache soil in addition to rock samples [2], which could be followed by future sample retrieval and return missions. Here we discuss key scientific consid-erations for sampling and caching soil samples on the proposed M-2020 rover, as well as the state in which samples would need to be preserved when received by analysts on Earth. We are seeking feedback on these draft plans as input to mission requirement formulation. A related planning exercise on rocks is reported in an accompanying abstract [3].

UPLC-MS/MS assay of riluzole in human plasma and cerebrospinal fluid (CSF): Application in samples from spinal cord injured patients.

Science.gov (United States)

Sarkar, Mahua; Grossman, Robert G; Toups, Elizabeth G; Chow, Diana S-L

2017-11-30

In the present study, a sensitive and robust LC-MS/MS method has been developed and validated for the quantification of riluzole in human plasma and cerebrospinal fluid (CSF) in clinical samples from patients with spinal cord injury (SCI). Riluzole and its labeled internal standard (IS) were isolated from plasma and CSF by liquid-liquid extraction using ethyl acetate. Riluzole (m/z 235→166) and IS (m/z 238→169) were detected by electrospray ionization (ESI) using multiple reaction monitoring (MRM) in a positive mode. The assay was linear in the concentration range of 0.5 (LLOQ, signal/noise ratio>10)-800ng/ml in plasma, and 1.0 (LLOQ)-800ng/ml in CSF samples. The intra- and inter-day accuracy in plasma were 94.2-110.0% and 97.8-102.0%, respectively, and those in CSF were 87.6-105.1% and 91.9-98.8%, respectively. The intra- and inter-day precision were 2.2-7.2% and 4.0-9.1%, respectively, in plasma, and 1.4-14.1% and 2.6-11.5%, respectively in CSF. Matrix effect was negligible from both matrices with signal percentages of 97.6-100.6% in plasma and 99.4-106.4% in CSF. The recoveries were >75% in plasma, >84% in CSF with low protein (53.9mg/dl), and >68% in CSF with high protein (348.2mg/dl). This method was successfully applied to quantify riluzole concentrations in plasma and CSF from patients with SCI. Copyright © 2017 Elsevier B.V. All rights reserved.

Stability of HE4 and CA125 in blood samples from patients diagnosed with ovarian cancer

DEFF Research Database (Denmark)

Sandhu, Noreen; Karlsen, Mona A; Høgdall, Claus

2014-01-01

OBJECTIVE: To investigate the influence of handling and storage on HE4 and CA125 serum and EDTA plasma levels to clarify any important consequences for a clinical setting. METHODS: Blood samples from 13 ovarian cancer (OC) patients were collected and allowed to clot or sediment for up to 72 hours.......024). No significant difference between CA125 serum and plasma levels were found (p = 0.46). Serum and EDTA plasma samples were stable during the eight cycles of freezing and thawing (CA125: all p > 0.2; HE4: all p > 0.5). CONCLUSION: No systematic difference could be demonstrated for HE4. CA125 is not dependent...

Preanalytical blood sample workup for cell-free DNA analysis using Droplet Digital PCR for future molecular cancer diagnostics.

Science.gov (United States)

van Ginkel, Joost H; van den Broek, Daan A; van Kuik, Joyce; Linders, Dorothé; de Weger, Roel; Willems, Stefan M; Huibers, Manon M H

2017-10-01

In current molecular cancer diagnostics, using blood samples of cancer patients for the detection of genetic alterations in plasma (cell-free) circulating tumor DNA (ctDNA) is an emerging practice. Since ctDNA levels in blood are low, highly sensitive Droplet Digital PCR (ddPCR) can be used for detecting rare mutational targets. In order to perform ddPCR on blood samples, a standardized procedure for processing and analyzing blood samples is necessary to facilitate implementation into clinical practice. Therefore, we assessed the technical sample workup procedure for ddPCR on blood plasma samples. Blood samples from healthy individuals, as well as lung cancer patients were analyzed. We compared different methods and protocols for sample collection, storage, centrifugation, isolation, and quantification. Cell-free DNA (cfDNA) concentrations of several wild-type targets and BRAF and EGFR-mutant ctDNA concentrations quantified by ddPCR were primary outcome measurements. Highest cfDNA concentrations were measured in blood collected in serum tubes. No significant differences in cfDNA concentrations were detected between various time points of up to 24 h until centrifugation. Highest cfDNA concentrations were detected after DNA isolation with the Quick cfDNA Serum & Plasma Kit, while plasma isolation using the QIAamp Circulating Nucleic Acid Kit yielded the most consistent results. DdPCR results on cfDNA are highly dependent on multiple factors during preanalytical sample workup, which need to be addressed during the development of this diagnostic tool for cancer diagnostics in the future. © 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Plasma cortisol and faecal cortisol metabolites concentrations in stereotypic and non-stereotypic horses: do stereotypic horses cope better with poor environmental conditions?

Directory of Open Access Journals (Sweden)

Fureix Carole

2013-01-01

Full Text Available Abstract Background Stereotypic behaviours, i.e. repetitive behaviours induced by frustration, repeated attempts to cope and/or brain dysfunction, are intriguing as they occur in a variety of domestic and captive species without any clear adaptive function. Among the different hypotheses, the coping hypothesis predicts that stereotypic behaviours provide a way for animals in unfavourable environmental conditions to adjust. As such, they are expected to have a lower physiological stress level (glucocorticoids than non-stereotypic animals. Attempts to link stereotypic behaviours with glucocorticoids however have yielded contradictory results. Here we investigated correlates of oral and motor stereotypic behaviours and glucocorticoid levels in two large samples of domestic horses (NStudy1 = 55, NStudy2 = 58, kept in sub-optimal conditions (e.g. confinement, social isolation, and already known to experience poor welfare states. Each horse was observed in its box using focal sampling (study 1 and instantaneous scan sampling (study 2. Plasma samples (collected in study 1 but also non-invasive faecal samples (collected in both studies were retrieved in order to assess cortisol levels. Results Results showed that 1 plasma cortisol and faecal cortisol metabolites concentrations did not differ between horses displaying stereotypic behaviours and non-stereotypic horses and 2 both oral and motor stereotypic behaviour levels did not predict plasma cortisol or faecal cortisol metabolites concentrations. Conclusions Cortisol measures, collected in two large samples of horses using both plasma sampling as well as faecal sampling (the latter method minimizing bias due to a non-invasive sampling procedure, therefore do not indicate that stereotypic horses cope better, at least in terms of adrenocortical activity.

PIXE Analysis of Atmospheric Aerosol Samples Collected in the Adirondack Mountains

Science.gov (United States)

Yoskowitz, Josh; Ali, Salina; Nadareski, Benjamin; Safiq, Alexandrea; Smith, Jeremy; Labrake, Scott; Vineyard, Michael

2013-10-01

We have performed an elemental analysis of atmospheric aerosol samples collected at Piseco Lake in Upstate New York using proton induced x-ray emission spectroscopy (PIXE). This work is part of a systematic study of airborne pollution in the Adirondack Mountains. Of particular interest is the sulfur content that can contribute to acid rain, a well-documented problem in the Adirondacks. We used a nine-stage cascade impactor to collect the samples and distribute the particulate matter onto Kapton foils by particle size. The PIXE experiments were performed with 2.2-MeV proton beams from the 1.1-MV pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. X-Ray energy spectra were measured with a silicon drift detector and analyzed with GUPIX software to determine the elemental concentrations of the aerosols. A broad range of elements from silicon to zinc were detected with significant sulfur concentrations measured for particulate matter between 0.25 and 0.5 μm in size. The PIXE analysis will be described and preliminary results will be presented.

Sample diagnosis using indicator elements and non-analyte signals for inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Antler, Margaret; Ying Hai; Burns, David H.; Salin, Eric D.

2003-01-01

A sample diagnosis procedure that uses both non-analyte and analyte signals to estimate matrix effects in inductively coupled plasma-mass spectrometry is presented. Non-analyte signals are those of background species in the plasma (e.g. N + , ArO + ), and changes in these signals can indicate changes in plasma conditions. Matrix effects of Al, Ba, Cs, K and Na on 19 non-analyte signals and 15 element signals were monitored. Multiple linear regression was used to build the prediction models, using a genetic algorithm for objective feature selection. Non-analyte elemental signals and non-analyte signals were compared for diagnosing matrix effects, and both were found to be suitable for estimating matrix effects. Individual analyte matrix effect estimation was compared with the overall matrix effect prediction, and models used to diagnose overall matrix effects were more accurate than individual analyte models. In previous work [Spectrochim. Acta Part B 57 (2002) 277], we tested models for analytical decision making. The current models were tested in the same way, and were able to successfully diagnose matrix effects with at least an 80% success rate

Determination of extremely low 236U/238U isotope ratios in environmental samples by sector-field inductively coupled plasma mass spectrometry using high-efficiency sample introduction

International Nuclear Information System (INIS)

Boulyga, Sergei F.; Heumann, Klaus G.

2006-01-01

A method by inductively coupled plasma mass spectrometry (Icp-Ms) was developed which allows the measurement of 236 U at concentration ranges down to 3 x 10 -14 g g -1 and extremely low 236 U/ 238 U isotope ratios in soil samples of 10 -7 . By using the high-efficiency solution introduction system APEX in connection with a sector-field ICP-MS a sensitivity of more than 5000 counts fg -1 uranium was achieved. The use of an aerosol desolvating unit reduced the formation rate of uranium hydride ions UH + /U + down to a level of 10 -6 . An abundance sensitivity of 3 x 10 -7 was observed for 236 U/ 238 U isotope ratio measurements at mass resolution 4000. The detection limit for 236 U and the lowest detectable 236 U/ 238 U isotope ratio were improved by more than two orders of magnitude compared with corresponding values by alpha spectrometry. Determination of uranium in soil samples collected in the vicinity of Chernobyl nuclear power plant (NPP) resulted in that the 236 U/ 238 U isotope ratio is a much more sensitive and accurate marker for environmental contamination by spent uranium in comparison to the 235 U/ 238 U isotope ratio. The ICP-MS technique allowed for the first time detection of irradiated uranium in soil samples even at distances more than 200 km to the north of Chernobyl NPP (Mogilev region). The concentration of 236 U in the upper 0-10 cm soil layers varied from 2 x 10 -9 g g -1 within radioactive spots close to the Chernobyl NPP to 3 x 10 -13 g g -1 on a sampling site located by >200 km from Chernobyl